EC 1.1.1.206     
Accepted name: tropinone reductase I
Reaction: tropine + NADP+ = tropinone + NADPH + H+
Glossary: tropine = 3α-hydroxytropane = tropan-3-endo-ol
Other name(s): tropine dehydrogenase; tropinone reductase (ambiguous); TR-I
Systematic name: tropine:NADP+ 3α-oxidoreductase
Comments: Also oxidizes other tropan-3α-ols, but not the corresponding β-derivatives [1]. This enzyme along with EC 1.1.1.236, tropinone reductase II, represents a branch point in tropane alkaloid metabolism [4]. Tropine (the product of EC 1.1.1.206) is incorporated into hyoscyamine and scopolamine whereas pseudotropine (the product of EC 1.1.1.236) is the first specific metabolite on the pathway to the calystegines [4]. Both enzymes are always found together in any given tropane-alkaloid-producing species, have a common substrate, tropinone, and are strictly stereospecific [3].
References:
1.  Koelen, K.J. and Gross, G.G. Partial purification and properties of tropine dehydrogenase from root cultures of Datura stramonium. Planta Med. 44 (1982) 227–230. [PMID: 17402126]
2.  Couladis, M.M, Friesen, J.B., Landgrebe, M.E. and Leete, E. Enzymes catalysing the reduction of tropinone to tropine and ψ-tropine isolated from the roots of Datura innoxia. Pytochemistry 30 (1991) 801–805.
3.  Nakajima, K., Hashimoto, T. and Yamada, Y. Two tropinone reductases with different stereospecificities are short-chain dehydrogenases evolved from a common ancestor. Proc. Natl. Acad. Sci. USA 90 (1993) 9591–9595. [PMID: 8415746]
4.  Dräger, B. Tropinone reductases, enzymes at the branch point of tropane alkaloid metabolism. Phytochemistry 67 (2006) 327–337. [PMID: 16426652]
[EC 1.1.1.206 created 1984, modified 2007]
 
 
EC 1.1.1.236     
Accepted name: tropinone reductase II
Reaction: pseudotropine + NADP+ = tropinone + NADPH + H+
Glossary: pseudotropine = ψ-tropine = 3β-hydroxytropane = tropan-3-exo-ol
Other name(s): tropinone (ψ-tropine-forming) reductase; pseudotropine forming tropinone reductase; tropinone reductase (ambiguous); TR-II
Systematic name: pseudotropine:NADP+ 3-oxidoreductase
Comments: This enzyme along with EC 1.1.1.206, tropine dehydrogenase, represents a branch point in tropane alkaloid metabolism [3]. Tropine (the product of EC 1.1.1.206) is incorporated into hyoscyamine and scopolamine whereas pseudotropine (the product of EC 1.1.1.236) is the first specific metabolite on the pathway to the calystegines [3]. Both enzymes are always found together in any given tropane-alkaloid-producing species, have a common substrate, tropinone, and are strictly stereospecific [2].
References:
1.  Dräger, B., Hashimoto, T. and Yamada, Y. Purification and characterization of pseudotropine forming tropinone reductase from Hyoscyamus niger root cultures. Agric. Biol. Chem. 52 (1988) 2663–2667.
2.  Couladis, M.M, Friesen, J.B., Landgrebe, M.E. and Leete, E. Enzymes catalysing the reduction of tropinone to tropine and ψ-tropine isolated from the roots of Datura innoxia. Pytochemistry 30 (1991) 801–805.
3.  Nakajima, K., Hashimoto, T. and Yamada, Y. Two tropinone reductases with different stereospecificities are short-chain dehydrogenases evolved from a common ancestor. Proc. Natl. Acad. Sci. USA 90 (1993) 9591–9595. [PMID: 8415746]
4.  Dräger, B. Tropinone reductases, enzymes at the branch point of tropane alkaloid metabolism. Phytochemistry 67 (2006) 327–337. [PMID: 16426652]
[EC 1.1.1.236 created 1992, modified 2007]
 
 
EC 1.1.1.258     
Accepted name: 6-hydroxyhexanoate dehydrogenase
Reaction: 6-hydroxyhexanoate + NAD+ = 6-oxohexanoate + NADH + H+
Systematic name: 6-hydroxyhexanoate:NAD+ oxidoreductase
Comments: Involved in the cyclohexanol degradation pathway in Acinetobacter NCIB 9871.
References:
1.  Donoghue, N.A. and Trudgill, P.W. The metabolism of cyclohexanol by Acinetobacter NCIB 9871. Eur. J. Biochem. 60 (1975) 1–7. [PMID: 1261]
2.  Hecker, L.I., Tondeur, Y. and Farrelly, J.G. Formation of ε-hydroxycaproate and ε-aminocaproate from N-nitrosohexamethyleneimine: evidence that microsomal α-hydroxylation of cyclic nitrosamines may not always involve the insertion of molecular oxygen into the substrate. Chem. Biol. Interact. 49 (1984) 235–248. [PMID: 6722936]
[EC 1.1.1.258 created 2000]
 
 
EC 1.1.1.288     
Accepted name: xanthoxin dehydrogenase
Reaction: xanthoxin + NAD+ = abscisic aldehyde + NADH + H+
Other name(s): xanthoxin oxidase; ABA2
Systematic name: xanthoxin:NAD+ oxidoreductase
Comments: Requires a molybdenum cofactor for activity. NADP+ cannot replace NAD+ and short-chain alcohols such as ethanol, isopropanol, butanol and cyclohexanol cannot replace xanthoxin as substrate [3]. Involved in the abscisic-acid biosynthesis pathway in plants, along with EC 1.2.3.14 (abscisic-aldehyde oxidase), EC 1.13.11.51 (9-cis-epoxycarotenoid dioxygenase) and EC 1.14.13.93 [(+)-abscisic acid 8′-hydroxylase]. Abscisic acid is a sesquiterpenoid plant hormone that is involved in the control of a wide range of essential physiological processes, including seed development, germination and responses to stress [3].
References:
1.  Sindhu, R.K. and Walton, D.C. Xanthoxin metabolism in cell-free preparations from wild type and wilty mutants of tomato. Plant Physiol. 88 (1988) 178–182. [PMID: 16666262]
2.  Schwartz, S.H., Leon-Kloosterziel, K.M., Koornneef, M. and Zeevaart, J.A. Biochemical characterization of the aba2 and aba3 mutants in Arabidopsis thaliana. Plant Physiol. 114 (1997) 161–166. [PMID: 9159947]
3.  González-Guzmán, M., Apostolova, N., Bellés, J.M., Barrero, J.M., Piqueras, P., Ponce, M.R., Micol, J.L., Serrano, R. and Rodríguez, P.L. The short-chain alcohol dehydrogenase ABA2 catalyzes the conversion of xanthoxin to abscisic aldehyde. Plant Cell 14 (2002) 1833–1846. [PMID: 12172025]
[EC 1.1.1.288 created 2005]
 
 
EC 1.1.1.293      
Deleted entry: tropinone reductase I. This enzyme was already in the Enzyme List as EC 1.1.1.206, tropine dehydrogenase so EC 1.1.1.293 has been withdrawn at the public-review stage
[EC 1.1.1.293 created 2007, withdrawn while undergoing public review]
 
 
EC 1.1.1.307     
Accepted name: D-xylose reductase
Reaction: xylitol + NAD(P)+ = D-xylose + NAD(P)H + H+
Other name(s): XylR; XyrA; msXR; dsXR; monospecific xylose reductase; dual specific xylose reductase; NAD(P)H-dependent xylose reductase; xylose reductase
Systematic name: xylitol:NAD(P)+ oxidoreductase
Comments: Xylose reductase catalyses the initial reaction in the xylose utilization pathway, the NAD(P)H dependent reduction of xylose to xylitol.
References:
1.  Neuhauser, W., Haltrich, D., Kulbe, K.D. and Nidetzky, B. NAD(P)H-dependent aldose reductase from the xylose-assimilating yeast Candida tenuis. Isolation, characterization and biochemical properties of the enzyme. Biochem. J. 326 (1997) 683–692. [PMID: 9307017]
2.  Nidetzky, B., Bruggler, K., Kratzer, R. and Mayr, P. Multiple forms of xylose reductase in Candida intermedia: comparison of their functional properties using quantitative structure-activity relationships, steady-state kinetic analysis, and pH studies. J. Agric. Food Chem. 51 (2003) 7930–7935. [PMID: 14690376]
3.  Iablochkova, E.N., Bolotnikova, O.I., Mikhailova, N.P., Nemova, N.N. and Ginak, A.I. The activity of xylose reductase and xylitol dehydrogenase in yeasts. Mikrobiologiia 72 (2003) 466–469. [PMID: 14526534] (in Russian)
4.  Chen, L.C., Huang, S.C., Chuankhayan, P., Chen, C.D., Huang, Y.C., Jeyakanthan, J., Pang, H.F., Men, L.C., Chen, Y.C., Wang, Y.K., Liu, M.Y., Wu, T.K. and Chen, C.J. Purification, crystallization and preliminary X-ray crystallographic analysis of xylose reductase from Candida tropicalis. Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. 65 (2009) 419–421. [PMID: 19342796]
5.  Verduyn, C., Van Kleef, R., Frank, J., Schreuder, H., Van Dijken, J.P. and Scheffers, W.A. Properties of the NAD(P)H-dependent xylose reductase from the xylose-fermenting yeast Pichia stipitis. Biochem. J. 226 (1985) 669–677. [PMID: 3921014]
6.  Fernandes, S., Tuohy, M.G. and Murray, P.G. Xylose reductase from the thermophilic fungus Talaromyces emersonii: cloning and heterologous expression of the native gene (Texr) and a double mutant (TexrK271R + N273D) with altered coenzyme specificity. J. Biosci. 34 (2009) 881–890. [PMID: 20093741]
7.  Lee, J.K., Koo, B.S. and Kim, S.Y. Cloning and characterization of the xyl1 gene, encoding an NADH-preferring xylose reductase from Candida parapsilosis, and its functional expression in Candida tropicalis. Appl. Environ. Microbiol. 69 (2003) 6179–6188. [PMID: 14532079]
8.  Woodyer, R., Simurdiak, M., van der Donk, W.A. and Zhao, H. Heterologous expression, purification, and characterization of a highly active xylose reductase from Neurospora crassa. Appl. Environ. Microbiol. 71 (2005) 1642–1647. [PMID: 15746370]
[EC 1.1.1.307 created 2010]
 
 
EC 1.1.1.312     
Accepted name: 2-hydroxy-4-carboxymuconate semialdehyde hemiacetal dehydrogenase
Reaction: 4-carboxy-2-hydroxymuconate semialdehyde hemiacetal + NADP+ = 2-oxo-2H-pyran-4,6-dicarboxylate + NADPH + H+
Other name(s): 2-hydroxy-4-carboxymuconate 6-semialdehyde dehydrogenase; 4-carboxy-2-hydroxy-cis,cis-muconate-6-semialdehyde:NADP+ oxidoreductase; α-hydroxy-γ-carboxymuconic ε-semialdehyde dehydrogenase; 4-carboxy-2-hydroxymuconate-6-semialdehyde dehydrogenase; LigC; ProD
Systematic name: 4-carboxy-2-hydroxymuconate semialdehyde hemiacetal:NADP+ 2-oxidoreductase
Comments: The enzyme does not act on unsubstituted aliphatic or aromatic aldehydes or glucose; NAD+ can replace NADP+, but with lower affinity. The enzyme was initially believed to act on 4-carboxy-2-hydroxy-cis,cis-muconate 6-semialdehyde and produce 4-carboxy-2-hydroxy-cis,cis-muconate [1]. However, later studies showed that the substrate is the hemiacetal form [3], and the product is 2-oxo-2H-pyran-4,6-dicarboxylate [2,4].
References:
1.  Maruyama, K., Ariga, N., Tsuda, M. and Deguchi, K. Purification and properties of α-hydroxy-γ-carboxymuconic ε-semialdehyde dehydrogenase. J. Biochem. (Tokyo) 83 (1978) 1125–1134. [PMID: 26671]
2.  Maruyama, K. Isolation and identification of the reaction product of α-hydroxy-γ-carboxymuconic ε-semialdehyde dehydrogenase. J. Biochem. 86 (1979) 1671–1677. [PMID: 528534]
3.  Maruyama, K. Purification and properties of 2-pyrone-4,6-dicarboxylate hydrolase. J. Biochem. (Tokyo) 93 (1983) 557–565. [PMID: 6841353]
4.  Masai, E., Momose, K., Hara, H., Nishikawa, S., Katayama, Y. and Fukuda, M. Genetic and biochemical characterization of 4-carboxy-2-hydroxymuconate-6-semialdehyde dehydrogenase and its role in the protocatechuate 4,5-cleavage pathway in Sphingomonas paucimobilis SYK-6. J. Bacteriol. 182 (2000) 6651–6658. [PMID: 11073908]
[EC 1.1.1.312 created 1978 as EC 1.2.1.45, transferred 2011 to EC 1.1.1.312]
 
 
EC 1.1.1.315     
Accepted name: 11-cis-retinol dehydrogenase
Reaction: 11-cis-retinol—[retinal-binding-protein] + NAD+ = 11-cis-retinal—[retinol-binding-protein] + NADH + H+
Glossary: 11-cis-retinal = 11-cis-retinaldehyde
Other name(s): RDH5 (gene name)
Systematic name: 11-cis-retinol:NAD+ oxidoreductase
Comments: This enzyme, abundant in the retinal pigment epithelium, catalyses the reduction of 11-cis-retinol to 11-cis-retinal [1] while the substrate is bound to the retinal-binding protein [4]. This is a crucial step in the regeneration of 11-cis-retinal, the chromophore of rhodopsin. The enzyme can also accept other cis forms of retinol [2].
References:
1.  Simon, A., Hellman, U., Wernstedt, C. and Eriksson, U. The retinal pigment epithelial-specific 11-cis retinol dehydrogenase belongs to the family of short chain alcohol dehydrogenases. J. Biol. Chem. 270 (1995) 1107–1112. [PMID: 7836368]
2.  Wang, J., Chai, X., Eriksson, U. and Napoli, J.L. Activity of human 11-cis-retinol dehydrogenase (Rdh5) with steroids and retinoids and expression of its mRNA in extra-ocular human tissue. Biochem. J. 338 (1999) 23–27. [PMID: 9931293]
3.  Liden, M., Romert, A., Tryggvason, K., Persson, B. and Eriksson, U. Biochemical defects in 11-cis-retinol dehydrogenase mutants associated with fundus albipunctatus. J. Biol. Chem. 276 (2001) 49251–49257. [PMID: 11675386]
4.  Wu, Z., Yang, Y., Shaw, N., Bhattacharya, S., Yan, L., West, K., Roth, K., Noy, N., Qin, J. and Crabb, J.W. Mapping the ligand binding pocket in the cellular retinaldehyde binding protein. J. Biol. Chem. 278 (2003) 12390–12396. [PMID: 12536149]
[EC 1.1.1.315 created 2011]
 
 
EC 1.1.1.316     
Accepted name: L-galactose 1-dehydrogenase
Reaction: L-galactose + NAD+ = L-galactono-1,4-lactone + NADH + H+
Other name(s): L-GalDH; L-galactose dehydrogenase
Systematic name: L-galactose:NAD+ 1-oxidoreductase
Comments: The enzyme catalyses a step in the ascorbate biosynthesis in higher plants (Smirnoff-Wheeler pathway). The activity with NADP+ is less than 10% of the activity with NAD+.
References:
1.  Mieda, T., Yabuta, Y., Rapolu, M., Motoki, T., Takeda, T., Yoshimura, K., Ishikawa, T. and Shigeoka, S. Feedback inhibition of spinach L-galactose dehydrogenase by L-ascorbate. Plant Cell Physiol. 45 (2004) 1271–1279. [PMID: 15509850]
2.  Gatzek, S., Wheeler, G.L. and Smirnoff, N. Antisense suppression of L-galactose dehydrogenase in Arabidopsis thaliana provides evidence for its role in ascorbate synthesis and reveals light modulated L-galactose synthesis. Plant J. 30 (2002) 541–553. [PMID: 12047629]
3.  Wheeler, G.L., Jones, M.A. and Smirnoff, N. The biosynthetic pathway of vitamin C in higher plants. Nature 393 (1998) 365–369. [PMID: 9620799]
4.  Oh, M.M., Carey, E.E. and Rajashekar, C.B. Environmental stresses induce health-promoting phytochemicals in lettuce. Plant Physiol. Biochem. 47 (2009) 578–583. [PMID: 19297184]
[EC 1.1.1.316 created 2011]
 
 
EC 1.1.1.330     
Accepted name: very-long-chain 3-oxoacyl-CoA reductase
Reaction: a very-long-chain (3R)-3-hydroxyacyl-CoA + NADP+ = a very-long-chain 3-oxoacyl-CoA + NADPH + H+
Glossary: a very-long-chain acyl-CoA = an acyl-CoA thioester where the acyl chain contains 23 or more carbon atoms.
Other name(s): very-long-chain 3-ketoacyl-CoA reductase; very-long-chain β-ketoacyl-CoA reductase; KCR (gene name); IFA38 (gene name)
Systematic name: (3R)-3-hydroxyacyl-CoA:NADP+ oxidoreductase
Comments: The second component of the elongase, a microsomal protein complex responsible for extending palmitoyl-CoA and stearoyl-CoA (and modified forms thereof) to very-long-chain acyl CoAs. The enzyme is active with substrates with chain length of C16 to C34, depending on the species. cf. EC 2.3.1.199, very-long-chain 3-oxoacyl-CoA synthase, EC 4.2.1.134, very-long-chain (3R)-3-hydroxyacyl-[acyl-carrier protein] dehydratase, and EC 1.3.1.93, very-long-chain enoyl-CoA reductase.
References:
1.  Beaudoin, F., Gable, K., Sayanova, O., Dunn, T. and Napier, J.A. A Saccharomyces cerevisiae gene required for heterologous fatty acid elongase activity encodes a microsomal β-keto-reductase. J. Biol. Chem. 277 (2002) 11481–11488. [PMID: 11792704]
2.  Han, G., Gable, K., Kohlwein, S.D., Beaudoin, F., Napier, J.A. and Dunn, T.M. The Saccharomyces cerevisiae YBR159w gene encodes the 3-ketoreductase of the microsomal fatty acid elongase. J. Biol. Chem. 277 (2002) 35440–35449. [PMID: 12087109]
3.  Beaudoin, F., Wu, X., Li, F., Haslam, R.P., Markham, J.E., Zheng, H., Napier, J.A. and Kunst, L. Functional characterization of the Arabidopsis β-ketoacyl-coenzyme A reductase candidates of the fatty acid elongase. Plant Physiol. 150 (2009) 1174–1191. [PMID: 19439572]
[EC 1.1.1.330 created 2012]
 
 
EC 1.1.1.358     
Accepted name: 2-dehydropantolactone reductase
Reaction: (R)-pantolactone + NADP+ = 2-dehydropantolactone + NADPH + H+
Other name(s): 2-oxopantoyl lactone reductase; 2-ketopantoyl lactone reductase; ketopantoyl lactone reductase; 2-dehydropantoyl-lactone reductase
Systematic name: (R)-pantolactone:NADP+ oxidoreductase
Comments: The enzyme participates in an alternative pathway for biosynthesis of (R)-pantothenate (vitamin B5). This entry covers enzymes whose stereo specificity for NADP+ is not known. cf. EC 1.1.1.168 2-dehydropantolactone reductase (Re-specific) and EC 1.1.1.214, 2-dehydropantolactone reductase (Si-specific).
References:
1.  Hata, H., Shimizu, S., Hattori, S. and Yamada, H. Ketopantoyl-lactone reductase from Candida parapsilosis: purification and characterization as a conjugated polyketone reductase. Biochim. Biophys. Acta 990 (1989) 175–181. [PMID: 2644973]
[EC 1.1.1.358 created 2013]
 
 
EC 1.1.1.385     
Accepted name: dihydroanticapsin dehydrogenase
Reaction: L-dihydroanticapsin + NAD+ = L-anticapsin + NADH + H+
Glossary: L-dihydroanticapsin = 3-[(1R,2S,5R,6S)-5-hydroxy-7-oxabicyclo[4.1.0]hept-2-yl]-L-alanine
L-anticapsin = 3-[(1R,2S,6R)-5-oxo-7-oxabicyclo[4.1.0]hept-2-yl]-L-alanine
Other name(s): BacC; ywfD (gene name)
Systematic name: L-dihydroanticapsin:NAD+ oxidoreductase
Comments: The enzyme, characterized from the bacterium Bacillus subtilis, is involved in the biosynthesis of the nonribosomally synthesized dipeptide antibiotic bacilysin, composed of L-alanine and L-anticapsin.
References:
1.  Parker, J.B. and Walsh, C.T. Action and timing of BacC and BacD in the late stages of biosynthesis of the dipeptide antibiotic bacilysin. Biochemistry 52 (2013) 889–901. [PMID: 23317005]
[EC 1.1.1.385 created 2015]
 
 
EC 1.1.1.418     
Accepted name: plant 3β-hydroxysteroid-4α-carboxylate 3-dehydrogenase (decarboxylating)
Reaction: a 3β-hydroxysteroid-4α-carboxylate + NAD+ = a 3-oxosteroid + CO2 + NADH
Other name(s): 3β-HSD/D1 (gene name); 3β-HSD/D2 (gene name); 3β-hydroxysteroid dehydrogenases/C-4 decarboxylase (ambiguous)
Systematic name: 3β-hydroxysteroid-4α-carboxylate:NAD+ 3-oxidoreductase (decarboxylating)
Comments: The enzyme, found in plants, catalyses multiple reactions during plant sterol biosynthesis. Unlike the fungal/animal enzyme EC 1.1.1.170, 3β-hydroxysteroid-4α-carboxylate 3-dehydrogenase (decarboxylating), the plant enzyme is specific for NAD+.
References:
1.  Rondet, S., Taton, M. and Rahier, A. Identification, characterization, and partial purification of 4 α-carboxysterol-C3-dehydrogenase/ C4-decarboxylase from Zea mays. Arch. Biochem. Biophys. 366 (1999) 249–260. [PMID: 10356290]
2.  Rahier, A., Darnet, S., Bouvier, F., Camara, B. and Bard, M. Molecular and enzymatic characterizations of novel bifunctional 3β-hydroxysteroid dehydrogenases/C-4 decarboxylases from Arabidopsis thaliana. J. Biol. Chem. 281 (2006) 27264–27277. [PMID: 16835224]
3.  Rahier, A., Bergdoll, M., Genot, G., Bouvier, F. and Camara, B. Homology modeling and site-directed mutagenesis reveal catalytic key amino acids of 3β-hydroxysteroid-dehydrogenase/C4-decarboxylase from Arabidopsis. Plant Physiol. 149 (2009) 1872–1886. [PMID: 19218365]
[EC 1.1.1.418 created 2019]
 
 
EC 1.1.3.20     
Accepted name: long-chain-alcohol oxidase
Reaction: a long-chain alcohol + O2 = a long-chain aldehyde + H2O2
Other name(s): long-chain fatty alcohol oxidase; fatty alcohol oxidase; fatty alcohol:oxygen oxidoreductase; long-chain fatty acid oxidase
Systematic name: long-chain-alcohol:oxygen oxidoreductase
Comments: Oxidizes long-chain fatty alcohols; best substrate is dodecyl alcohol.
References:
1.  Moreau, R.A. and Huang, A.H.C. Oxidation of fatty alcohol in the cotyledons of jojoba seedlings. Arch. Biochem. Biophys. 194 (1979) 422–430. [PMID: 36040]
2.  Moreau, R.A. and Huang, A.H.C. Enzymes of wax ester catabolism in jojoba. Methods Enzymol. 71 (1981) 804–813.
3.  Cheng, Q., Liu, H.T., Bombelli, P., Smith, A. and Slabas, A.R. Functional identification of AtFao3, a membrane bound long chain alcohol oxidase in Arabidopsis thaliana. FEBS Lett. 574 (2004) 62–68. [PMID: 15358540]
4.  Zhao, S., Lin, Z., Ma, W., Luo, D. and Cheng, Q. Cloning and characterization of long-chain fatty alcohol oxidase LjFAO1 in Lotus japonicus. Biotechnol. Prog. 24 (2008) 773–779. [PMID: 18396913]
5.  Cheng, Q., Sanglard, D., Vanhanen, S., Liu, H.T., Bombelli, P., Smith, A. and Slabas, A.R. Candida yeast long chain fatty alcohol oxidase is a c-type haemoprotein and plays an important role in long chain fatty acid metabolism. Biochim. Biophys. Acta 1735 (2005) 192–203. [PMID: 16046182]
[EC 1.1.3.20 created 1984, modified 2010]
 
 
EC 1.1.3.46     
Accepted name: 4-hydroxymandelate oxidase
Reaction: (S)-4-hydroxymandelate + O2 = 2-(4-hydroxyphenyl)-2-oxoacetate + H2O2
Glossary: (S)-4-hydroxymandelate = (S)-2-hydroxy-2-(4-hydroxyphenyl)acetate
2-(4-hydroxyphenyl)-2-oxoacetate = 4-hydroxyphenylglyoxylate = (4-hydroxyphenyl)(oxo)acetate
L-(4-hydroxyphenyl)glycine = (S)-4-hydroxyphenylglycine
L-(3,5-dihydroxyphenyl)glycine = (S)-3,5-dihydroxyphenylglycine
Other name(s): 4HmO; HmO
Systematic name: (S)-4-hydroxymandelate:oxygen 1-oxidoreductase
Comments: A flavoprotein (FMN). The enzyme from the bacterium Amycolatopsis orientalis is involved in the biosynthesis of L-(4-hydroxyphenyl)glycine and L-(3,5-dihydroxyphenyl)glycine, two non-proteinogenic amino acids occurring in the vancomycin group of antibiotics.
References:
1.  Hubbard, B.K., Thomas, M.G. and Walsh, C.T. Biosynthesis of L-p-hydroxyphenylglycine, a non-proteinogenic amino acid constituent of peptide antibiotics. Chem. Biol. 7 (2000) 931–942. [PMID: 11137816]
2.  Li, T.L., Choroba, O.W., Charles, E.H., Sandercock, A.M., Williams, D.H. and Spencer, J.B. Characterisation of a hydroxymandelate oxidase involved in the biosynthesis of two unusual amino acids occurring in the vancomycin group of antibiotics. Chem. Commun. (Camb.) (2001) 1752–1753. [PMID: 12240298]
[EC 1.1.3.46 created 2014]
 
 
EC 1.1.5.3     
Accepted name: glycerol-3-phosphate dehydrogenase
Reaction: sn-glycerol 3-phosphate + a quinone = glycerone phosphate + a quinol
Glossary: glycerone phosphate = dihydroxyacetone phosphate = 3-hydroxy-2-oxopropyl phosphate
Other name(s): α-glycerophosphate dehydrogenase; α-glycerophosphate dehydrogenase (acceptor); anaerobic glycerol-3-phosphate dehydrogenase; DL-glycerol 3-phosphate oxidase (misleading); FAD-dependent glycerol-3-phosphate dehydrogenase; FAD-dependent sn-glycerol-3-phosphate dehydrogenase; FAD-GPDH; FAD-linked glycerol 3-phosphate dehydrogenase; FAD-linked L-glycerol-3-phosphate dehydrogenase; flavin-linked glycerol-3-phosphate dehydrogenase; flavoprotein-linked L-glycerol 3-phosphate dehydrogenase; glycerol 3-phosphate cytochrome c reductase (misleading); glycerol phosphate dehydrogenase; glycerol phosphate dehydrogenase (acceptor); glycerol phosphate dehydrogenase (FAD); glycerol-3-phosphate CoQ reductase; glycerol-3-phosphate dehydrogenase (flavin-linked); glycerol-3-phosphate:CoQ reductase; glycerophosphate dehydrogenase; L-3-glycerophosphate-ubiquinone oxidoreductase; L-glycerol-3-phosphate dehydrogenase (ambiguous); L-glycerophosphate dehydrogenase; mGPD; mitochondrial glycerol phosphate dehydrogenase; NAD+-independent glycerol phosphate dehydrogenase; pyridine nucleotide-independent L-glycerol 3-phosphate dehydrogenase; sn-glycerol 3-phosphate oxidase (misleading); sn-glycerol-3-phosphate dehydrogenase; sn-glycerol-3-phosphate:(acceptor) 2-oxidoreductase; sn-glycerol-3-phosphate:acceptor 2-oxidoreductase
Systematic name: sn-glycerol 3-phosphate:quinone oxidoreductase
Comments: This flavin-dependent dehydrogenase is an essential membrane enzyme, functioning at the central junction of glycolysis, respiration and phospholipid biosynthesis. In bacteria, the enzyme is localized to the cytoplasmic membrane [6], while in eukaryotes it is tightly bound to the outer surface of the inner mitochondrial membrane [2]. In eukaryotes, this enzyme, together with the cytosolic enzyme EC 1.1.1.8, glycerol-3-phosphate dehydrogenase (NAD+), forms the glycerol-3-phosphate shuttle by which NADH produced in the cytosol, primarily from glycolysis, can be reoxidized to NAD+ by the mitochondrial electron-transport chain [3]. This shuttle plays a critical role in transferring reducing equivalents from cytosolic NADH into the mitochondrial matrix [7,8]. Insect flight muscle uses only CoQ10 as the physiological quinone whereas hamster and rat mitochondria use mainly CoQ9 [4]. The enzyme is activated by calcium [3].
References:
1.  Ringler, R.L. Studies on the mitochondrial α-glycerophosphate dehydrogenase. II. Extraction and partial purification of the dehydrogenase from pig brain. J. Biol. Chem. 236 (1961) 1192–1198. [PMID: 13741763]
2.  Schryvers, A., Lohmeier, E. and Weiner, J.H. Chemical and functional properties of the native and reconstituted forms of the membrane-bound, aerobic glycerol-3-phosphate dehydrogenase of Escherichia coli. J. Biol. Chem. 253 (1978) 783–788. [PMID: 340460]
3.  MacDonald, M.J. and Brown, L.J. Calcium activation of mitochondrial glycerol phosphate dehydrogenase restudied. Arch. Biochem. Biophys. 326 (1996) 79–84. [PMID: 8579375]
4.  Rauchová, H., Fato, R., Drahota, Z. and Lenaz, G. Steady-state kinetics of reduction of coenzyme Q analogs by glycerol-3-phosphate dehydrogenase in brown adipose tissue mitochondria. Arch. Biochem. Biophys. 344 (1997) 235–241. [PMID: 9244403]
5.  Shen, W., Wei, Y., Dauk, M., Zheng, Z. and Zou, J. Identification of a mitochondrial glycerol-3-phosphate dehydrogenase from Arabidopsis thaliana: evidence for a mitochondrial glycerol-3-phosphate shuttle in plants. FEBS Lett. 536 (2003) 92–96. [PMID: 12586344]
6.  Walz, A.C., Demel, R.A., de Kruijff, B. and Mutzel, R. Aerobic sn-glycerol-3-phosphate dehydrogenase from Escherichia coli binds to the cytoplasmic membrane through an amphipathic α-helix. Biochem. J. 365 (2002) 471–479. [PMID: 11955283]
7.  Ansell, R., Granath, K., Hohmann, S., Thevelein, J.M. and Adler, L. The two isoenzymes for yeast NAD+-dependent glycerol 3-phosphate dehydrogenase encoded by GPD1 and GPD2 have distinct roles in osmoadaptation and redox regulation. EMBO J. 16 (1997) 2179–2187. [PMID: 9171333]
8.  Larsson, C., Påhlman, I.L., Ansell, R., Rigoulet, M., Adler, L. and Gustafsson, L. The importance of the glycerol 3-phosphate shuttle during aerobic growth of Saccharomyces cerevisiae. Yeast 14 (1998) 347–357. [PMID: 9559543]
[EC 1.1.5.3 created 1961 as EC 1.1.2.1, transferred 1965 to EC 1.1.99.5, transferred 2009 to EC 1.1.5.3]
 
 
EC 1.1.99.36     
Accepted name: alcohol dehydrogenase (nicotinoprotein)
Reaction: ethanol + acceptor = acetaldehyde + reduced acceptor
Other name(s): NDMA-dependent alcohol dehydrogenase; nicotinoprotein alcohol dehydrogenase; np-ADH; ethanol:N,N-dimethyl-4-nitrosoaniline oxidoreductase
Systematic name: ethanol:acceptor oxidoreductase
Comments: Contains Zn2+. Nicotinoprotein alcohol dehydrogenases are unique medium-chain dehydrogenases/reductases (MDR) alcohol dehydrogenases that have a tightly bound NAD+/NADH cofactor that does not dissociate during the catalytic process. Instead, the cofactor is regenerated by a second substrate or electron carrier. While the in vivo electron acceptor is not known, N,N-dimethyl-4-nitrosoaniline (NDMA), which is reduced to 4-(hydroxylamino)-N,N-dimethylaniline, can serve this function in vitro. The enzyme from the Gram-positive bacterium Amycolatopsis methanolica can accept many primary alcohols as substrates, including benzylalcohol [1].
References:
1.  Van Ophem, P.W., Van Beeumen, J. and Duine, J.A. Nicotinoprotein [NAD(P)-containing] alcohol/aldehyde oxidoreductases. Purification and characterization of a novel type from Amycolatopsis methanolica. Eur. J. Biochem. 212 (1993) 819–826. [PMID: 8385013]
2.  Piersma, S.R., Visser, A.J., de Vries, S. and Duine, J.A. Optical spectroscopy of nicotinoprotein alcohol dehydrogenase from Amycolatopsis methanolica: a comparison with horse liver alcohol dehydrogenase and UDP-galactose epimerase. Biochemistry 37 (1998) 3068–3077. [PMID: 9485460]
3.  Schenkels, P. and Duine, J.A. Nicotinoprotein (NADH-containing) alcohol dehydrogenase from Rhodococcus erythropolis DSM 1069: an efficient catalyst for coenzyme-independent oxidation of a broad spectrum of alcohols and the interconversion of alcohols and aldehydes. Microbiology 146 (2000) 775–785. [PMID: 10784035]
4.  Piersma, S.R., Norin, A., de Vries, S., Jornvall, H. and Duine, J.A. Inhibition of nicotinoprotein (NAD+-containing) alcohol dehydrogenase by trans-4-(N,N-dimethylamino)-cinnamaldehyde binding to the active site. J. Protein Chem. 22 (2003) 457–461. [PMID: 14690248]
5.  Norin, A., Piersma, S.R., Duine, J.A. and Jornvall, H. Nicotinoprotein (NAD+ -containing) alcohol dehydrogenase: structural relationships and functional interpretations. Cell. Mol. Life Sci. 60 (2003) 999–1006. [PMID: 12827287]
[EC 1.1.99.36 created 2010]
 
 
EC 1.1.99.37     
Accepted name: methanol dehydrogenase (nicotinoprotein)
Reaction: methanol + acceptor = formaldehyde + reduced acceptor
Other name(s): NDMA-dependent methanol dehydrogenase; nicotinoprotein methanol dehydrogenase; methanol:N,N-dimethyl-4-nitrosoaniline oxidoreductase
Systematic name: methanol:acceptor oxidoreductase
Comments: Contains Zn2+ and Mg2+. Nicotinoprotein methanol dehydrogenases have a tightly bound NADP+/NADPH cofactor that does not dissociate during the catalytic process. Instead, the cofactor is regenerated by a second substrate or electron carrier. While the in vivo electron acceptor is not known, N,N-dimethyl-4-nitrosoaniline (NDMA), which is reduced to 4-(hydroxylamino)-N,N-dimethylaniline, can serve this function in vitro. The enzyme has been detected in several Gram-positive methylotrophic bacteria, including Amycolatopsis methanolica, Rhodococcus rhodochrous and Rhodococcus erythropolis [1-3]. These enzymes are decameric, and possess a 5-fold symmetry [4]. Some of the enzymes can also dismutate formaldehyde to methanol and formate [5].
References:
1.  Vonck, J., Arfman, N., De Vries, G.E., Van Beeumen, J., Van Bruggen, E.F. and Dijkhuizen, L. Electron microscopic analysis and biochemical characterization of a novel methanol dehydrogenase from the thermotolerant Bacillus sp. C1. J. Biol. Chem. 266 (1991) 3949–3954. [PMID: 1995642]
2.  Van Ophem, P.W., Van Beeumen, J. and Duine, J.A. Nicotinoprotein [NAD(P)-containing] alcohol/aldehyde oxidoreductases. Purification and characterization of a novel type from Amycolatopsis methanolica. Eur. J. Biochem. 212 (1993) 819–826. [PMID: 8385013]
3.  Bystrykh, L.V., Vonck, J., van Bruggen, E.F., van Beeumen, J., Samyn, B., Govorukhina, N.I., Arfman, N., Duine, J.A. and Dijkhuizen, L. Electron microscopic analysis and structural characterization of novel NADP(H)-containing methanol: N,N′-dimethyl-4-nitrosoaniline oxidoreductases from the gram-positive methylotrophic bacteria Amycolatopsis methanolica and Mycobacterium gastri MB19. J. Bacteriol. 175 (1993) 1814–1822. [PMID: 8449887]
4.  Hektor, H.J., Kloosterman, H. and Dijkhuizen, L. Identification of a magnesium-dependent NAD(P)(H)-binding domain in the nicotinoprotein methanol dehydrogenase from Bacillus methanolicus. J. Biol. Chem. 277 (2002) 46966–46973. [PMID: 12351635]
5.  Park, H., Lee, H., Ro, Y.T. and Kim, Y.M. Identification and functional characterization of a gene for the methanol : N,N′-dimethyl-4-nitrosoaniline oxidoreductase from Mycobacterium sp. strain JC1 (DSM 3803). Microbiology 156 (2010) 463–471. [PMID: 19875438]
[EC 1.1.99.37 created 2010]
 
 
EC 1.1.99.39     
Accepted name: D-2-hydroxyglutarate dehydrogenase
Reaction: (R)-2-hydroxyglutarate + acceptor = 2-oxoglutarate + reduced acceptor
Other name(s): D2HGDH (gene name)
Systematic name: (R)-2-hydroxyglutarate:acceptor 2-oxidoreductase
Comments: Contains FAD. The enzyme has no activity with NAD+ or NADP+, and was assayed in vitro using artificial electron acceptors. It has lower activity with (R)-lactate, (R)-2-hydroxybutyrate and meso-tartrate, and no activity with the (S) isomers. The mammalian enzyme is stimulated by Zn2+, Co2+ and Mn2+.
References:
1.  Engqvist, M., Drincovich, M.F., Flugge, U.I. and Maurino, V.G. Two D-2-hydroxy-acid dehydrogenases in Arabidopsis thaliana with catalytic capacities to participate in the last reactions of the methylglyoxal and β-oxidation pathways. J. Biol. Chem. 284 (2009) 25026–25037. [PMID: 19586914]
2.  Achouri, Y., Noel, G., Vertommen, D., Rider, M.H., Veiga-Da-Cunha, M. and Van Schaftingen, E. Identification of a dehydrogenase acting on D-2-hydroxyglutarate. Biochem. J. 381 (2004) 35–42. [PMID: 15070399]
[EC 1.1.99.39 created 2013]
 
 
EC 1.2.1.32     
Accepted name: aminomuconate-semialdehyde dehydrogenase
Reaction: 2-aminomuconate 6-semialdehyde + NAD+ + H2O = 2-aminomuconate + NADH + 2 H+
Other name(s): 2-aminomuconate semialdehyde dehydrogenase; 2-hydroxymuconic acid semialdehyde dehydrogenase; 2-hydroxymuconate semialdehyde dehydrogenase; α-aminomuconic ε-semialdehyde dehydrogenase; α-hydroxymuconic ε-semialdehyde dehydrogenase; 2-hydroxymuconic semialdehyde dehydrogenase
Systematic name: 2-aminomuconate-6-semialdehyde:NAD+ 6-oxidoreductase
Comments: Also acts on 2-hydroxymuconate semialdehyde.
References:
1.  Ichiyama, A., Nakamura, S., Kawai, H., Honjo, T., Nishizuka, Y., Hayaishi, O. and Senoh, S. Studies on the metabolism of the benzene ring of tryptophan in mammalian tissues. II. Enzymic formation of α-aminomuconic acid from 3-hydroxyanthranilic acid. J. Biol. Chem. 240 (1965) 740–749. [PMID: 14275130]
[EC 1.2.1.32 created 1972]
 
 
EC 1.2.1.45      
Transferred entry: 4-carboxy-2-hydroxymuconate-6-semialdehyde dehydrogenase. Now EC 1.1.1.312, 2-hydroxy-4-carboxymuconate semialdehyde hemiacetal dehydrogenase.
[EC 1.2.1.45 created 1978, deleted 2011]
 
 
EC 1.2.1.82     
Accepted name: β-apo-4′-carotenal oxygenase
Reaction: 4′-apo-β,ψ-caroten-4′-al + NAD+ + H2O = neurosporaxanthin + NADH + 2 H+
Glossary: neurosporaxanthin = 4′-apo-β,ψ-caroten-4′-oic acid
Other name(s): β-apo-4′-carotenal dehydrogenase; YLO-1; carD (gene name)
Systematic name: 4′-apo-β,ψ-carotenal:NAD+ oxidoreductase
Comments: Neurosporaxanthin is responsible for the orange color of of Neurospora.
References:
1.  Estrada, A.F., Youssar, L., Scherzinger, D., Al-Babili, S. and Avalos, J. The ylo-1 gene encodes an aldehyde dehydrogenase responsible for the last reaction in the Neurospora carotenoid pathway. Mol. Microbiol. 69 (2008) 1207–1220. [PMID: 18627463]
2.  Diaz-Sanchez, V., Estrada, A.F., Trautmann, D., Al-Babili, S. and Avalos, J. The gene carD encodes the aldehyde dehydrogenase responsible for neurosporaxanthin biosynthesis in Fusarium fujikuroi. FEBS J. 278 (2011) 3164–3176. [PMID: 21749649]
[EC 1.2.1.82 created 2011]
 
 
EC 1.2.3.7     
Accepted name: indole-3-acetaldehyde oxidase
Reaction: (indol-3-yl)acetaldehyde + H2O + O2 = (indol-3-yl)acetate + H2O2
Other name(s): indoleacetaldehyde oxidase; IAAld oxidase; AO1; indole-3-acetaldehyde:oxygen oxidoreductase
Systematic name: (indol-3-yl)acetaldehyde:oxygen oxidoreductase
Comments: A hemoprotein. This enzyme is an isoform of aldehyde oxidase (EC 1.2.3.1). It has a preference for aldehydes having an indole-ring structure as substrate [6,7]. It may play a role in plant hormone biosynthesis as its activity is higher in the auxin-overproducing mutant, super-root1, than in wild-type Arabidopsis thaliana [7]. While (indol-3-yl)acetaldehyde is the preferred substrate, it also oxidizes indole-3-carbaldehyde and acetaldehyde, but more slowly. The enzyme from maize contains FAD, iron and molybdenum [4].
References:
1.  Bower, P.J., Brown, H.M. and Purves, W.K. Cucumber seedling indoleacetaldehyde oxidase. Plant Physiol. 61 (1978) 107–110. [PMID: 16660220]
2.  Miyata, S., Suzuki, Y., Kamisaka, S. and Masuda, Y. Indole-3-acetaldehyde oxidase of pea-seedlings. Physiol. Plant. 51 (1981) 402–406.
3.  Rajagopal, R. Metabolism of indole-3-acetaldehyde. III. Some characteristics of the aldehyde oxidase of Avena coleoptiles. Physiol. Plant. 24 (1971) 272–281.
4.  Koshiba, T., Saito, E., Ono, N., Yamamoto, N. and Sato, M. Purification and properties of flavin- and molybdenum-containing aldehyde oxidase from coleoptiles of maize. Plant Physiol. 110 (1996) 781–789. [PMID: 12226218]
5.  Koshiba, T. and Matsuyama, H. An in vitro system of indole-3-acetic acid formation from tryptophan in maize (Zea mays) coleoptile extracts. Plant Physiol. 102 (1993) 1319–1324. [PMID: 12231908]
6.  Sekimoto, H., Seo, M., Kawakami, N., Komano, T., Desloire, S., Liotenberg, S., Marion-Poll, A., Caboche, M., Kamiya, Y. and Koshiba, T. Molecular cloning and characterization of aldehyde oxidases in Arabidopsis thaliana. Plant Cell Physiol. 39 (1998) 433–442. [PMID: 9615466]
7.  Seo, M., Akaba, S., Oritani, T., Delarue, M., Bellini, C., Caboche, M. and Koshiba, T. Higher activity of an aldehyde oxidase in the auxin-overproducing superroot1 mutant of Arabidopsis thaliana. Plant Physiol. 116 (1998) 687–693. [PMID: 9489015]
[EC 1.2.3.7 created 1984, modified 2004, modified 2006]
 
 
EC 1.2.3.14     
Accepted name: abscisic-aldehyde oxidase
Reaction: abscisic aldehyde + H2O + O2 = abscisate + H2O2
Other name(s): abscisic aldehyde oxidase; AAO3; AOd; AOδ
Systematic name: abscisic-aldehyde:oxygen oxidoreductase
Comments: Acts on both (+)- and (-)-abscisic aldehyde. Involved in the abscisic-acid biosynthesis pathway in plants, along with EC 1.1.1.288, (xanthoxin dehydrogenase), EC 1.13.11.51 (9-cis-epoxycarotenoid dioxygenase) and EC 1.14.13.93 [(+)-abscisic acid 8′-hydroxylase]. While abscisic aldehyde is the best substrate, the enzyme also acts with indole-3-aldehyde, 1-naphthaldehyde and benzaldehyde as substrates, but more slowly [3].
References:
1.  Sagi, M., Fluhr, R. and Lips, S.H. Aldehyde oxidase and xanthin dehydrogenase in a flacca tomato mutant with deficient abscisic acid and wilty phenotype. Plant Physiol. 120 (1999) 571–577. [PMID: 10364409]
2.  Seo, M., Peeters, A.J., Koiwai, H., Oritani, T., Marion-Poll, A., Zeevaart, J.A., Koornneef, M., Kamiya, Y. and Koshiba, T. The Arabidopsis aldehyde oxidase 3 (AAO3) gene product catalyzes the final step in abscisic acid biosynthesis in leaves. Proc. Natl. Acad. Sci. USA 97 (2000) 12908–12913. [PMID: 11050171]
3.  Seo, M., Koiwai, H., Akaba, S., Komano, T., Oritani, T., Kamiya, Y. and Koshiba, T. Abscisic aldehyde oxidase in leaves of Arabidopsis thaliana. Plant J. 23 (2000) 481–488. [PMID: 10972874]
[EC 1.2.3.14 created 2005]
 
 
EC 1.3.1.74     
Accepted name: 2-alkenal reductase [NAD(P)+]
Reaction: a n-alkanal + NAD(P)+ = an alk-2-enal + NAD(P)H + H+
Other name(s): NAD(P)H-dependent alkenal/one oxidoreductase; NADPH:2-alkenal α,β-hydrogenase; 2-alkenal reductase
Systematic name: n-alkanal:NAD(P)+ 2-oxidoreductase
Comments: Highly specific for 4-hydroxynon-2-enal and non-2-enal. Alk-2-enals of shorter chain have lower affinities. Exhibits high activities also for alk-2-enones such as but-3-en-2-one and pent-3-en-2-one. Inactive with cyclohex-2-en-1-one and 12-oxophytodienoic acid. Involved in the detoxication of α,β-unsaturated aldehydes and ketones [cf. EC 1.3.1.102, 2-alkenal reductase (NADP+)].
References:
1.  Mano, J., Torii, Y., Hayashi, S., Takimoto, K., Matsui, K., Nakamura, K., Inzé, D., Babiychuk, E., Kushnir, S. and Asada, K. The NADPH:quinone oxidoreductase P1-ζ-crystallin in Arabidopsis catalyzes the α,β-hydrogenation of 2-alkenals: detoxication of the lipid peroxide-derived reactive aldehydes. Plant Cell Physiol. 43 (2002) 1445–1455. [PMID: 12514241]
2.  Dick, R.A., Kwak, M.K., Sutter, T.R. and Kensler, T.W. Antioxidative function and substrate specificity of NAD(P)H-dependent alkenal/one oxidoreductase. A new role for leukotriene B4 12-hydroxydehydrogenase/15-oxoprostaglandin 13-reductase. J. Biol. Chem. 276 (2001) 40803–40810. [PMID: 11524419]
[EC 1.3.1.74 created 2003, modified 2014]
 
 
EC 1.3.1.75     
Accepted name: 3,8-divinyl protochlorophyllide a 8-vinyl-reductase (NADPH)
Reaction: protochlorophyllide a + NADP+ = 3,8-divinyl protochlorophyllide a + NADPH + H+
Other name(s): DVR (gene name); bciA (gene name); [4-vinyl]chlorophyllide a reductase; 4VCR; chlorophyllide-a:NADP+ oxidoreductase; divinyl chlorophyllide a 8-vinyl-reductase; plant-type divinyl chlorophyllide a 8-vinyl-reductase
Systematic name: protochlorophyllide-a:NADP+ C-81-oxidoreductase
Comments: The enzyme, found in higher plants, green algae, and some phototrophic bacteria, is involved in the production of monovinyl versions of (bacterio)chlorophyll pigments from their divinyl precursors. It can also act on 3,8-divinyl chlorophyllide a. cf. EC 1.3.7.13, 3,8-divinyl protochlorophyllide a 8-vinyl-reductase (ferredoxin).
References:
1.  Tripathy, B.C. and Rebeiz, C.A. Chloroplast biogenesis 60. Conversion of divinyl protochlorophyllide to monovinyl protochlorophyllide in green(ing) barley, a dark monovinyl/light divinyl plant species. Plant Physiol. 87 (1988) 89–94. [PMID: 16666133]
2.  Parham, R. and Rebeiz, C.A. Chloroplast biogenesis: [4-vinyl] chlorophyllide a reductase is a divinyl chlorophyllide a-specific, NADPH-dependent enzyme. Biochemistry 31 (1992) 8460–8464. [PMID: 1390630]
3.  Parham, R. and Rebeiz, C.A. Chloroplast biogenesis 72: a [4-vinyl]chlorophyllide a reductase assay using divinyl chlorophyllide a as an exogenous substrate. Anal. Biochem. 231 (1995) 164–169. [PMID: 8678296]
4.  Kolossov, V.L. and Rebeiz, C.A. Chloroplast biogenesis 84: solubilization and partial purification of membrane-bound [4-vinyl]chlorophyllide a reductase from etiolated barley leaves. Anal. Biochem. 295 (2001) 214–219. [PMID: 11488624]
5.  Nagata, N., Tanaka, R., Satoh, S. and Tanaka, A. Identification of a vinyl reductase gene for chlorophyll synthesis in Arabidopsis thaliana and implications for the evolution of Prochlorococcus species. Plant Cell 17 (2005) 233–240. [PMID: 15632054]
6.  Chew, A.G. and Bryant, D.A. Characterization of a plant-like protochlorophyllide a divinyl reductase in green sulfur bacteria. J. Biol. Chem. 282 (2007) 2967–2975. [PMID: 17148453]
[EC 1.3.1.75 created 2003, modified 2016]
 
 
EC 1.3.1.77     
Accepted name: anthocyanidin reductase [(2R,3R)-flavan-3-ol-forming]
Reaction: a (2R,3R)-flavan-3-ol + 2 NAD(P)+ = an anthocyanidin with a 3-hydroxy group + 2 NAD(P)H + H+
Other name(s): ANR (gene name) (ambiguous); flavan-3-ol:NAD(P)+ oxidoreductase; anthocyanidin reductase (ambiguous)
Systematic name: (2R,3R)-flavan-3-ol:NAD(P)+ 3,4-oxidoreductase
Comments: The enzyme participates in the flavonoid biosynthesis pathway found in plants. It catalyses the double reduction of anthocyanidins, producing (2R,3R)-flavan-3-ol monomers required for the formation of proanthocyanidins. While the enzyme from the legume Medicago truncatula (MtANR) can use both NADPH and NADH as reductant, that from the crucifer Arabidopsis thaliana (AtANR) uses only NADPH. Also, while the substrate preference of MtANR is cyanidin>pelargonidin>delphinidin, the reverse preference is found with AtANR. cf. EC 1.3.1.112, anthocyanidin reductase [(2S)-flavan-3-ol-forming].
References:
1.  Xie, D.Y., Sharma, S.B., Paiva, N.L., Ferreira, D. and Dixon, R.A. Role of anthocyanidin reductase, encoded by BANYULS in plant flavonoid biosynthesis. Science 299 (2003) 396–399. [PMID: 12532018]
2.  Xie, D.Y., Sharma, S.B. and Dixon, R.A. Anthocyanidin reductases from Medicago truncatula and Arabidopsis thaliana. Arch. Biochem. Biophys. 422 (2004) 91–102. [PMID: 14725861]
3.  Pang, Y., Abeysinghe, I.S., He, J., He, X., Huhman, D., Mewan, K.M., Sumner, L.W., Yun, J. and Dixon, R.A. Functional characterization of proanthocyanidin pathway enzymes from tea and their application for metabolic engineering. Plant Physiol. 161 (2013) 1103–1116. [PMID: 23288883]
[EC 1.3.1.77 created 2004, modified 2016]
 
 
EC 1.3.1.78     
Accepted name: arogenate dehydrogenase (NADP+)
Reaction: L-arogenate + NADP+ = L-tyrosine + NADPH + CO2
Glossary: L-arogenate = 1-[(2S)-2-amino-2-carboxyethyl]-4-hydroxycyclohexa-2,5-diene-1-carboxylate
Other name(s): arogenic dehydrogenase (ambiguous); pretyrosine dehydrogenase (ambiguous); TyrAAT1; TyrAAT2; TyrAa
Systematic name: L-arogenate:NADP+ oxidoreductase (decarboxylating)
Comments: Arogenate dehydrogenases may utilize NAD+ (EC 1.3.1.43), NADP+ (EC 1.3.1.78), or both (EC 1.3.1.79). NADP+-dependent enzymes usually predominate in higher plants.The enzyme from the cyanobacterium Synechocystis sp. PCC 6803 and the TyrAAT1 isoform of the plant Arabidopsis thaliana cannot use prephenate as a substrate, while the Arabidopsis isoform TyrAAT2 can use it very poorly [2,3].
References:
1.  Gaines, C.G., Byng, G.S., Whitaker, R.J. and Jensen, R.A. L-Tyrosine regulation and biosynthesis via arogenate dehydrogenase in suspension-cultured cells of Nicotiana silvestris Speg. et Comes. Planta 156 (1982) 233–240. [PMID: 24272471]
2.  Rippert, P. and Matringe, M. Purification and kinetic analysis of the two recombinant arogenate dehydrogenase isoforms of Arabidopsis thaliana. Eur. J. Biochem. 269 (2002) 4753–4761. [PMID: 12354106]
3.  Bonner, C.A., Jensen, R.A., Gander, J.E. and Keyhani, N.O. A core catalytic domain of the TyrA protein family: arogenate dehydrogenase from Synechocystis. Biochem. J. 382 (2004) 279–291. [PMID: 15171683]
[EC 1.3.1.78 created 2005]
 
 
EC 1.3.1.93     
Accepted name: very-long-chain enoyl-CoA reductase
Reaction: a very-long-chain acyl-CoA + NADP+ = a very-long-chain trans-2,3-dehydroacyl-CoA + NADPH + H+
Glossary: a very-long-chain acyl-CoA = an acyl-CoA thioester where the acyl chain contains 23 or more carbon atoms.
Other name(s): TSC13 (gene name); CER10 (gene name)
Systematic name: very-long-chain acyl-CoA:NADP+ oxidoreductase
Comments: This is the fourth component of the elongase, a microsomal protein complex responsible for extending palmitoyl-CoA and stearoyl-CoA (and modified forms thereof) to very-long-chain acyl CoAs. cf. EC 2.3.1.199, very-long-chain 3-oxoacyl-CoA synthase, EC 1.1.1.330, very-long-chain 3-oxoacyl-CoA reductase, and EC 4.2.1.134, very-long-chain (3R)-3-hydroxyacyl-CoA dehydratase.
References:
1.  Kohlwein, S.D., Eder, S., Oh, C.S., Martin, C.E., Gable, K., Bacikova, D. and Dunn, T. Tsc13p is required for fatty acid elongation and localizes to a novel structure at the nuclear-vacuolar interface in Saccharomyces cerevisiae. Mol. Cell Biol. 21 (2001) 109–125. [PMID: 11113186]
2.  Gable, K., Garton, S., Napier, J.A. and Dunn, T.M. Functional characterization of the Arabidopsis thaliana orthologue of Tsc13p, the enoyl reductase of the yeast microsomal fatty acid elongating system. J. Exp. Bot. 55 (2004) 543–545. [PMID: 14673020]
3.  Kvam, E., Gable, K., Dunn, T.M. and Goldfarb, D.S. Targeting of Tsc13p to nucleus-vacuole junctions: a role for very-long-chain fatty acids in the biogenesis of microautophagic vesicles. Mol. Biol. Cell 16 (2005) 3987–3998. [PMID: 15958487]
4.  Zheng, H., Rowland, O. and Kunst, L. Disruptions of the Arabidopsis enoyl-CoA reductase gene reveal an essential role for very-long-chain fatty acid synthesis in cell expansion during plant morphogenesis. Plant Cell 17 (2005) 1467–1481. [PMID: 15829606]
[EC 1.3.1.93 created 2012]
 
 
EC 1.3.5.1     
Accepted name: succinate dehydrogenase
Reaction: succinate + a quinone = fumarate + a quinol
Other name(s): succinate dehydrogenase (quinone); succinate dehydrogenase (ubiquinone); succinic dehydrogenase; complex II (ambiguous); succinate dehydrogenase complex; SDH (ambiguous); succinate:ubiquinone oxidoreductase
Systematic name: succinate:quinone oxidoreductase
Comments: A flavoprotein (FAD) complex containing iron-sulfur centres. The enzyme is found in the inner mitochondrial membrane in eukaryotes and the plasma membrane of many aerobic or facultative bacteria and archaea. It catalyses succinate oxidation in the citric acid cycle and transfers the electrons to quinones in the membrane, thus constituting a part of the aerobic respiratory chain (known as complex II). In vivo the enzyme uses the quinone found in the organism - eukaryotic enzymes utilize ubiquinone, bacterial enzymes utilize ubiquinone or menaquinone, and archaebacterial enzymes from the Sulfolobus genus use caldariellaquinone. cf. EC 1.3.5.4, fumarate reductase (quinol).
References:
1.  Kita, K., Vibat, C.R., Meinhardt, S., Guest, J.R. and Gennis, R.B. One-step purification from Escherichia coli of complex II (succinate: ubiquinone oxidoreductase) associated with succinate-reducible cytochrome b556. J. Biol. Chem. 264 (1989) 2672–2677. [PMID: 2644269]
2.  Hatefi, Y., Ragan, C.I. and Galante, Y.M. The enzymes and the enzyme complexes of the mitochondrial oxidative phosphorylation system. In: Martonosi, A. (Ed.), The Enzymes of Biological Membranes, 2nd edn, vol. 4, Plenum Press, New York, 1985, pp. 1–70.
3.  Moll, R. and Schafer, G. Purification and characterisation of an archaebacterial succinate dehydrogenase complex from the plasma membrane of the thermoacidophile Sulfolobus acidocaldarius. Eur. J. Biochem. 201 (1991) 593–600. [PMID: 1935955]
4.  Figueroa, P., Leon, G., Elorza, A., Holuigue, L., Araya, A. and Jordana, X. The four subunits of mitochondrial respiratory complex II are encoded by multiple nuclear genes and targeted to mitochondria in Arabidopsis thaliana. Plant Mol. Biol. 50 (2002) 725–734. [PMID: 12374303]
5.  Cecchini, G. Function and structure of complex II of the respiratory chain. Annu. Rev. Biochem. 72 (2003) 77–109. [PMID: 14527321]
6.  Oyedotun, K.S. and Lemire, B.D. The quaternary structure of the Saccharomyces cerevisiae succinate dehydrogenase. Homology modeling, cofactor docking, and molecular dynamics simulation studies. J. Biol. Chem. 279 (2004) 9424–9431. [PMID: 14672929]
7.  Kurokawa, T. and Sakamoto, J. Purification and characterization of succinate:menaquinone oxidoreductase from Corynebacterium glutamicum. Arch. Microbiol. 183 (2005) 317–324. [PMID: 15883782]
[EC 1.3.5.1 created 1983 (EC 1.3.99.1 created 1961, incorporated 2014)]
 
 
EC 1.3.5.6     
Accepted name: 9,9′-dicis-ζ-carotene desaturase
Reaction: 9,9′-dicis-ζ-carotene + 2 quinone = 7,9,7′,9′-tetracis-lycopene + 2 quinol (overall reaction)
(1a) 9,9′-dicis-ζ-carotene + a quinone = 7,9,9′-tricis-neurosporene + a quinol
(1b) 7,9,9′-tricis-neurosporene + a quinone = 7,9,7′,9′-tetracis-lycopene + a quinol
Glossary: prolycopene = 7,9,7′,9′-tetracis-lycopene
Other name(s): ζ-carotene desaturase; ZDS
Systematic name: 9,9′-dicis-ζ-corotene:quinone oxidoreductase
Comments: This enzyme is involved in carotenoid biosynthesis in plants and cyanobacteria.
References:
1.  Albrecht, M., Linden, H. and Sandmann, G. Biochemical characterization of purified ζ-carotene desaturase from Anabaena PCC 7120 after expression in E. coli. Eur. J. Biochem. 236 (1996) 115–120. [PMID: 8617254]
2.  Josse, E.M., Simkin, A.J., Gaffe, J., Laboure, A.M., Kuntz, M. and Carol, P. A plastid terminal oxidase associated with carotenoid desaturation during chromoplast differentiation. Plant Physiol. 123 (2000) 1427–1436. [PMID: 10938359]
3.  Breitenbach, J., Kuntz, M., Takaichi, S. and Sandmann, G. Catalytic properties of an expressed and purified higher plant type ζ-carotene desaturase from Capsicum annuum. Eur. J. Biochem. 265 (1999) 376–383. [PMID: 10491195]
4.  Breitenbach, J. and Sandmann, G. ζ-Carotene cis isomers as products and substrates in the plant poly-cis carotenoid biosynthetic pathway to lycopene. Planta 220 (2005) 785–793. [PMID: 15503129]
[EC 1.3.5.6 created 1999 as EC 1.14.99.30, transferred 2011 to EC 1.3.5.6]
 
 
EC 1.3.99.37     
Accepted name: 1-hydroxy-2-isopentenylcarotenoid 3,4-desaturase
Reaction: (1) dihydroisopentenyldehydrorhodopin + acceptor = isopentenyldehydrorhodopin + reduced acceptor
(2) dihydrobisanhydrobacterioruberin + acceptor = bisanhydrobacterioruberin + reduced acceptor
Glossary: bisanhydrobacterioruberin = (2S,2S′)-2,2′-bis(3-methylbut-2-en-1-yl)-3,4-didehydro-1,1′,2,2′-tetrahydro-ψ,ψ-carotene-1,1′-diol
dihydrobisanhydrobacterioruberin = (2S,2S′)-2,2′-bis(3-methylbut-2-en-1-yl)-3,3′,4,4′-tetradehydro-1,1′,2,2′-tetrahydro-ψ,ψ-carotene-1,1′-diol
dihydroisopentenyldehydrorhodopin = (2S)-2-(3-methylbut-2-en-1-yl)-3,4-didehydro-1,2-dihydro-ψ,ψ-caroten-1-ol
isopentenyldehydrorhodopin = (2S)-2-(3-methylbut-2-en-1-yl)-1,2-dihydro-ψ,ψ-caroten-1-ol
Other name(s): crtD (gene name)
Systematic name: dihydroisopentenyldehydrorhodopin:acceptor 3,4-oxidoreductase
Comments: The enzyme, isolated from the archaeon Haloarcula japonica, is involved in the biosynthesis of the C50 carotenoid bacterioruberin. In this pathway it catalyses the desaturation of the C-3,4 double bond in dihydroisopentenyldehydrorhodopin and the desaturation of the C-3′,4′ double bond in dihydrobisanhydrobacterioruberin.
References:
1.  Yang, Y., Yatsunami, R., Ando, A., Miyoko, N., Fukui, T., Takaichi, S. and Nakamura, S. Complete biosynthetic pathway of the C50 carotenoid bacterioruberin from lycopene in the extremely halophilic archaeon Haloarcula japonica. J. Bacteriol. 197 (2015) 1614–1623. [PMID: 25712483]
[EC 1.3.99.37 created 2015]
 
 
EC 1.3.99.39     
Accepted name: carotenoid φ-ring synthase
Reaction: carotenoid β-end group + 2 acceptor = carotenoid φ-end group + 2 reduced acceptor
Glossary: chlorobactene = φ,ψ-carotene
β-isorenieratene = φ,β-carotene
isorenieratene = φ,φ-carotene
Other name(s): crtU (gene name) (ambiguous)
Systematic name: carotenoid β-ring:acceptor oxidoreductase/methyltranferase (φ-ring-forming)
Comments: The enzyme, found in green sulfur bacteria, some cyanobacteria and some actinobacteria, introduces additional double bonds to the carotenoid β-end group, leading to aromatization of the ionone ring. As a result, one of the methyl groups at C-1 is transferred to position C-2. It is involved in the biosynthesis of carotenoids with φ-type aromatic end groups such as chlorobactene, β-isorenieratene, and isorenieratene.
References:
1.  Moshier, S.E. and Chapman, D.J. Biosynthetic studies on aromatic carotenoids. Biosynthesis of chlorobactene. Biochem. J. 136 (1973) 395–404. [PMID: 4774401]
2.  Krugel, H., Krubasik, P., Weber, K., Saluz, H.P. and Sandmann, G. Functional analysis of genes from Streptomyces griseus involved in the synthesis of isorenieratene, a carotenoid with aromatic end groups, revealed a novel type of carotenoid desaturase. Biochim. Biophys. Acta 1439 (1999) 57–64. [PMID: 10395965]
3.  Frigaard, N.U., Maresca, J.A., Yunker, C.E., Jones, A.D. and Bryant, D.A. Genetic manipulation of carotenoid biosynthesis in the green sulfur bacterium Chlorobium tepidum. J. Bacteriol. 186 (2004) 5210–5220. [PMID: 15292122]
[EC 1.3.99.39 created 2018]
 
 
EC 1.3.99.40     
Accepted name: carotenoid χ-ring synthase
Reaction: carotenoid β-end group + 2 acceptor = carotenoid χ-end group + 2 reduced acceptor
Glossary: okenone = 1′-methoxy-1′,2′-dihydro-χ,ψ-caroten-4′-one
renierapurpurin = χ,χ-carotene
synechoxanthin = χ,χ-caroten-18,18′-dioate
Other name(s): crtU (gene name) (ambiguous); cruE (gene name)
Systematic name: carotenoid β-ring:acceptor oxidoreductase/methyltranferase (χ-ring-forming)
Comments: The enzyme, found in purple sulfur bacteria (Chromatiaceae) and some cyanobacteria, is involved in the biosynthesis of carotenoids that contain χ-type end groups, such as okenone, renierapurpurin, and synechoxanthin.
References:
1.  Graham, J.E. and Bryant, D.A. The Biosynthetic pathway for synechoxanthin, an aromatic carotenoid synthesized by the euryhaline, unicellular cyanobacterium Synechococcus sp. strain PCC 7002. J. Bacteriol. 190 (2008) 7966–7974. [PMID: 18849428]
2.  Vogl, K. and Bryant, D.A. Biosynthesis of the biomarker okenone: χ-ring formation. Geobiology 10 (2012) 205–215. [PMID: 22070388]
[EC 1.3.99.40 created 2018]
 
 
EC 1.4.1.16     
Accepted name: diaminopimelate dehydrogenase
Reaction: meso-2,6-diaminoheptanedioate + H2O + NADP+ = L-2-amino-6-oxoheptanedioate + NH3 + NADPH + H+
Other name(s): meso-α,ε-diaminopimelate dehydrogenase; meso-diaminopimelate dehydrogenase
Systematic name: meso-2,6-diaminoheptanedioate:NADP+ oxidoreductase (deaminating)
References:
1.  Misono, H., Togawa, H., Yamamoto, T. and Soda, K. Occurrence of meso-α,ε-diaminopimelate dehydrogenase in Bacillus sphaericus. Biochem. Biophys. Res. Commun. 72 (1976) 89–93. [PMID: 10904]
2.  Misono, H., Togawa, H., Yamamoto, T. and Soda, K. meso-α,ε-Diaminopimelate D-dehydrogenase: distribution and the reaction product. J. Bacteriol. 137 (1979) 22–27. [PMID: 762012]
[EC 1.4.1.16 created 1981]
 
 
EC 1.4.1.18     
Accepted name: lysine 6-dehydrogenase
Reaction: L-lysine + NAD+ = (S)-2,3,4,5-tetrahydropyridine-2-carboxylate + NADH + H+ + NH3 (overall reaction)
(1a) L-lysine + NAD+ + H2O = (S)-2-amino-6-oxohexanoate + NADH + H+ + NH3
(1b) (S)-2-amino-6-oxohexanoate = (S)-2,3,4,5-tetrahydropyridine-2-carboxylate + H2O (spontaneous)
Glossary: (S)-2-amino-6-oxohexanoate = L-2-aminoadipate 6-semialdehyde = L-allysine
L-1-piperideine 6-carboxylate = (S)-2,3,4,5-tetrahydropyridine-2-carboxylate = (S)-1,6-didehydropiperidine-2-carboxylate
Other name(s): L-lysine ε-dehydrogenase; L-lysine 6-dehydrogenase; LysDH
Systematic name: L-lysine:NAD+ 6-oxidoreductase (deaminating)
Comments: The enzyme is highly specific for L-lysine as substrate, although S-(2-aminoethyl)-L-cysteine can act as a substrate, but more slowly. While the enzyme from Agrobacterium tumefaciens can use only NAD+, that from the thermophilic bacterium Geobacillus stearothermophilus can also use NADP+, but more slowly [1,4].
References:
1.  Misono, H. and Nagasaki, S. Occurrence of L-lysine ε-dehydrogenase in Agrobacterium tumefaciens. J. Bacteriol. 150 (1982) 398–401. [PMID: 6801024]
2.  Misono, H., Uehigashi, H., Morimoto, E. and Nagasaki, S. Purification and properties of L-lysine ε-dehydrogenase from Agrobacterium tumefaciens. Agric. Biol. Chem. 49 (1985) 2253–2255.
3.  Misono, H., Hashimoto, H., Uehigashi, H., Nagata, S. and Nagasaki, S. Properties of L-lysine ε-dehydrogenase from Agrobacterium tumefaciens. J. Biochem. (Tokyo) 105 (1989) 1002–1008. [PMID: 2768207]
4.  Heydari, M., Ohshima, T., Nunoura-Kominato, N. and Sakuraba, H. Highly stable L-lysine 6-dehydrogenase from the thermophile Geobacillus stearothermophilus isolated from a Japanese hot spring: characterization, gene cloning and sequencing, and expression. Appl. Environ. Microbiol. 70 (2004) 937–942. [PMID: 14766574]
[EC 1.4.1.18 created 1989, modified 2006, modified 2011]
 
 
EC 1.4.1.22      
Deleted entry: ornithine cyclodeaminase. It was pointed out during the public-review process that there is no overall consumption of NAD+ during the reaction. As a result, transfer of the enzyme from EC 4.3.1.12 was not necessary and EC 1.4.1.22 was withdrawn before being made official
[EC 1.4.1.22 created 2006, deleted 2006]
 
 
EC 1.4.3.16     
Accepted name: L-aspartate oxidase
Reaction: L-aspartate + O2 = iminosuccinate + H2O2
Other name(s): NadB; Laspo; AO
Systematic name: L-aspartate:oxygen oxidoreductase
Comments: A flavoprotein (FAD). L-Aspartate oxidase catalyses the first step in the de novo biosynthesis of NAD+ in some bacteria. O2 can be replaced by fumarate as electron acceptor, yielding succinate [5]. The ability of the enzyme to use both O2 and fumarate in cofactor reoxidation enables it to function under both aerobic and anaerobic conditions [5]. Iminosuccinate can either be hydrolysed to form oxaloacetate and NH3 or can be used by EC 2.5.1.72, quinolinate synthase, in the production of quinolinate. The enzyme is a member of the succinate dehydrogenase/fumarate-reductase family of enzymes [5].
References:
1.  Nasu, S., Wicks, F.D. and Gholson, R.K. L-Aspartate oxidase, a newly discovered enzyme of Escherichia coli, is the B protein of quinolinate synthetase. J. Biol. Chem. 257 (1982) 626–632. [PMID: 7033218]
2.  Mortarino, M., Negri, A., Tedeschi, G., Simonic, T., Duga, S., Gassen, H.G. and Ronchi, S. L-Aspartate oxidase from Escherichia coli. I. Characterization of coenzyme binding and product inhibition. Eur. J. Biochem. 239 (1996) 418–426. [PMID: 8706749]
3.  Tedeschi, G., Negri, A., Mortarino, M., Ceciliani, F., Simonic, T., Faotto, L. and Ronchi, S. L-Aspartate oxidase from Escherichia coli. II. Interaction with C4 dicarboxylic acids and identification of a novel L-aspartate: fumarate oxidoreductase activity. Eur. J. Biochem. 239 (1996) 427–433. [PMID: 8706750]
4.  Mattevi, A., Tedeschi, G., Bacchella, L., Coda, A., Negri, A. and Ronchi, S. Structure of L-aspartate oxidase: implications for the succinate dehydrogenase/fumarate reductase oxidoreductase family. Structure 7 (1999) 745–756. [PMID: 10425677]
5.  Bossi, R.T., Negri, A., Tedeschi, G. and Mattevi, A. Structure of FAD-bound L-aspartate oxidase: insight into substrate specificity and catalysis. Biochemistry 41 (2002) 3018–3024. [PMID: 11863440]
6.  Katoh, A., Uenohara, K., Akita, M. and Hashimoto, T. Early steps in the biosynthesis of NAD in Arabidopsis start with aspartate and occur in the plastid. Plant Physiol. 141 (2006) 851–857. [PMID: 16698895]
[EC 1.4.3.16 created 1984, modified 2008]
 
 
EC 1.4.3.20     
Accepted name: L-lysine 6-oxidase
Reaction: L-lysine + O2 + H2O = (S)-2-amino-6-oxohexanoate + H2O2 + NH3
Glossary: (S)-2-amino-6-oxohexanoate = L-2-aminoadipate 6-semialdehyde = L-allysine
Other name(s): L-lysine-ε-oxidase; Lod; LodA; marinocine
Systematic name: L-lysine:oxygen 6-oxidoreductase (deaminating)
Comments: Differs from EC 1.4.3.13, protein-lysine 6-oxidase, by using free L-lysine rather than the protein-bound form. N2-Acetyl-L-lysine is also a substrate, but N6-acetyl-L-lysine, which has an acetyl group at position 6, is not a substrate. Also acts on L-ornithine, D-lysine and 4-hydroxy-L-lysine, but more slowly. The amines cadaverine and putrescine are not substrates [2].
References:
1.  Lucas-Elío, P., Gómez, D., Solano, F. and Sanchez-Amat, A. The antimicrobial activity of marinocine, synthesized by Marinomonas mediterranea, is due to hydrogen peroxide generated by its lysine oxidase activity. J. Bacteriol. 188 (2006) 2493–2501. [PMID: 16547036]
2.  Gómez, D., Lucas-Elío, P., Sanchez-Amat, A. and Solano, F. A novel type of lysine oxidase: L-lysine-ε-oxidase. Biochim. Biophys. Acta 1764 (2006) 1577–1585. [PMID: 17030025]
[EC 1.4.3.20 created 2006, modified 2011]
 
 
EC 1.5.1.7     
Accepted name: saccharopine dehydrogenase (NAD+, L-lysine-forming)
Reaction: N6-(L-1,3-dicarboxypropyl)-L-lysine + NAD+ + H2O = L-lysine + 2-oxoglutarate + NADH + H+
Glossary: L-saccharopine = N6-(L-1,3-dicarboxypropyl)-L-lysine
Other name(s): lysine-2-oxoglutarate reductase; dehydrogenase, saccharopine (nicotinamide adenine dinucleotide, lysine forming); ε-N-(L-glutaryl-2)-L-lysine:NAD oxidoreductase (L-lysine forming); N6-(glutar-2-yl)-L-lysine:NAD oxidoreductase (L-lysine-forming); 6-N-(L-1,3-dicarboxypropyl)-L-lysine:NAD+ oxidoreductase (L-lysine-forming)
Systematic name: N6-(L-1,3-dicarboxypropyl)-L-lysine:NAD+ oxidoreductase (L-lysine-forming)
References:
1.  Fujioka, M. and Nakatani, Y. Saccharopine dehydrogenase. Interaction with substrate analogues. Eur. J. Biochem. 25 (1972) 301–307. [PMID: 4339117]
2.  Saunders, P.P. and Broquist, H.P. Saccharopine, an intermediate of the aminoadipic acid pathway of lysine biosynthesis. IV. Saccharopine dehydrogenase. J. Biol. Chem. 241 (1966) 3435–3440. [PMID: 4287986]
[EC 1.5.1.7 created 1972]
 
 
EC 1.5.1.8     
Accepted name: saccharopine dehydrogenase (NADP+, L-lysine-forming)
Reaction: N6-(L-1,3-dicarboxypropyl)-L-lysine + NADP+ + H2O = L-lysine + 2-oxoglutarate + NADPH + H+
Glossary: L-saccharopine = N6-(L-1,3-dicarboxypropyl)-L-lysine
Other name(s): lysine-2-oxoglutarate reductase; lysine-ketoglutarate reductase; L-lysine-α-ketoglutarate reductase; lysine:α-ketoglutarate:TPNH oxidoreductase (ε-N-[gultaryl-2]-L-lysine forming); saccharopine (nicotinamide adenine dinucleotide phosphate, lysine-forming) dehydrogenase; 6-N-(L-1,3-dicarboxypropyl)-L-lysine:NADP+ oxidoreductase (L-lysine-forming)
Systematic name: N6-(L-1,3-dicarboxypropyl)-L-lysine:NADP+ oxidoreductase (L-lysine-forming)
References:
1.  Hutzler, J. and Dancis, J. Conversion of lysine to saccharopine by human tissues. Biochim. Biophys. Acta 158 (1968) 62–69. [PMID: 4385118]
2.  Markovitz, P.J., Chuang, D.T. and Cox, R.P. Familial hyperlysinemias. Purification and characterization of the bifunctional aminoadipic semialdehyde synthase with lysine-ketoglutarate reductase and saccharopine dehydrogenase activities. J. Biol. Chem. 259 (1984) 11643–11646. [PMID: 6434529]
[EC 1.5.1.8 created 1972]
 
 
EC 1.5.1.10     
Accepted name: saccharopine dehydrogenase (NADP+, L-glutamate-forming)
Reaction: N6-(L-1,3-dicarboxypropyl)-L-lysine + NADP+ + H2O = L-glutamate + (S)-2-amino-6-oxohexanoate + NADPH + H+
Glossary: L-saccharopine = N6-(L-1,3-dicarboxypropyl)-L-lysine
(S)-2-amino-6-oxohexanoate = L-2-aminoadipate 6-semialdehyde = L-allysine
Other name(s): saccharopine (nicotinamide adenine dinucleotide phosphate, glutamate-forming) dehydrogenase; aminoadipic semialdehyde-glutamic reductase; aminoadipate semialdehyde-glutamate reductase; aminoadipic semialdehyde-glutamate reductase; ε-N-(L-glutaryl-2)-L-lysine:NAD+(P) oxidoreductase (L-2-aminoadipate-semialdehyde forming); saccharopine reductase; 6-N-(L-1,3-dicarboxypropyl)-L-lysine:NADP+ oxidoreductase (L-glutamate-forming)
Systematic name: N6-(L-1,3-dicarboxypropyl)-L-lysine:NADP+ oxidoreductase (L-glutamate-forming)
References:
1.  Jones, E.E. and Broquist, H.P. Saccharopine, an intermediate of the aminoadipic acid pathway of lysine biosynthesis. 3. Aminoadipic semialdehyde-glutamate reductase. J. Biol. Chem. 241 (1966) 3430–3434. [PMID: 4380448]
[EC 1.5.1.10 created 1972, modified 2011]
 
 
EC 1.5.3.4     
Accepted name: N6-methyl-lysine oxidase
Reaction: N6-methyl-L-lysine + H2O + O2 = L-lysine + formaldehyde + H2O2
Other name(s): ε-alkyl-L-lysine:oxygen oxidoreductase ; N6-methyllysine oxidase; ε-N-methyllysine demethylase; ε-alkyllysinase; 6-N-methyl-L-lysine:oxygen oxidoreductase (demethylating)
Systematic name: N6-methyl-L-lysine:oxygen oxidoreductase (demethylating)
References:
1.  Kim, S., Benoiton, L. and Paik, W.K. α-Alkyllysinase. Purification and properties of the enzyme. J. Biol. Chem. 239 (1964) 3790–3796. [PMID: 14257609]
[EC 1.5.3.4 created 1972]
 
 
EC 1.5.3.16     
Accepted name: spermine oxidase
Reaction: spermine + O2 + H2O = spermidine + 3-aminopropanal + H2O2
Other name(s): PAOh1/SMO; PAOh1 (ambiguous); AtPAO1; AtPAO4; SMO; mSMO; SMO(PAOh1); SMO/PAOh1; SMO5; mSMOmu
Systematic name: spermidine:oxygen oxidoreductase (spermidine-forming)
Comments: The enzyme from Arabidopsis thaliana (AtPAO1) oxidizes norspermine to norspermidine with high efficiency [3]. The mammalian enzyme, encoded by the SMOX gene, is a cytosolic enzyme that catalyses the oxidation of spermine at the exo (three-carbon) side of the tertiary amine. No activity with spermidine. Weak activity with N1-acetylspermine. A flavoprotein (FAD). Differs in specificity from EC 1.5.3.13 (N1-acetylpolyamine oxidase), EC 1.5.3.14 (polyamine oxidase (propane-1,3-diamine-forming)), EC 1.5.3.15 (N8-acetylspermidine oxidase (propane-1,3-diamine-forming) and EC 1.5.3.17 (non-specific polyamine oxidase).
References:
1.  Murray-Stewart, T., Wang, Y., Goodwin, A., Hacker, A., Meeker, A. and Casero, R.A., Jr. Nuclear localization of human spermine oxidase isoforms - possible implications in drug response and disease etiology. FEBS J. 275 (2008) 2795–2806. [PMID: 18422650]
2.  Cervelli, M., Polticelli, F., Federico, R. and Mariottini, P. Heterologous expression and characterization of mouse spermine oxidase. J. Biol. Chem. 278 (2003) 5271–5276. [PMID: 12458219]
3.  Tavladoraki, P., Rossi, M.N., Saccuti, G., Perez-Amador, M.A., Polticelli, F., Angelini, R. and Federico, R. Heterologous expression and biochemical characterization of a polyamine oxidase from Arabidopsis involved in polyamine back conversion. Plant Physiol. 141 (2006) 1519–1532. [PMID: 16778015]
4.  Wang, Y., Murray-Stewart, T., Devereux, W., Hacker, A., Frydman, B., Woster, P.M. and Casero, R.A., Jr. Properties of purified recombinant human polyamine oxidase, PAOh1/SMO. Biochem. Biophys. Res. Commun. 304 (2003) 605–611. [PMID: 12727196]
[EC 1.5.3.16 created 2009]
 
 
EC 1.5.3.17     
Accepted name: non-specific polyamine oxidase
Reaction: (1) spermine + O2 + H2O = spermidine + 3-aminopropanal + H2O2
(2) spermidine + O2 + H2O = putrescine + 3-aminopropanal + H2O2
(3) N1-acetylspermine + O2 + H2O = spermidine + 3-acetamidopropanal + H2O2
(4) N1-acetylspermidine + O2 + H2O = putrescine + 3-acetamidopropanal + H2O2
Other name(s): polyamine oxidase (ambiguous); Fms1; AtPAO3
Systematic name: polyamine:oxygen oxidoreductase (3-aminopropanal or 3-acetamidopropanal-forming)
Comments: A flavoprotein (FAD). The non-specific polyamine oxidases may differ from each other considerably. The enzyme from Saccharomyces cerevisiae shows a rather broad specificity and also oxidizes N8-acetylspermidine [3]. The enzyme from Ascaris suum shows high activity with spermine and spermidine, but also oxidizes norspermine [2]. The enzyme from Arabidopsis thaliana shows high activity with spermidine, but also oxidizes other polyamines [1]. The specific polyamine oxidases are classified as EC 1.5.3.13 (N1-acetylpolyamine oxidase), EC 1.5.3.14 (polyamine oxidase (propane-1,3-diamine-forming)), EC 1.5.3.15 (N8-acetylspermidine oxidase (propane-1,3-diamine-forming)) and EC 1.5.3.16 (spermine oxidase).
References:
1.  Moschou, P.N., Sanmartin, M., Andriopoulou, A.H., Rojo, E., Sanchez-Serrano, J.J. and Roubelakis-Angelakis, K.A. Bridging the gap between plant and mammalian polyamine catabolism: a novel peroxisomal polyamine oxidase responsible for a full back-conversion pathway in Arabidopsis. Plant Physiol. 147 (2008) 1845–1857. [PMID: 18583528]
2.  Muller, S. and Walter, R.D. Purification and characterization of polyamine oxidase from Ascaris suum. Biochem. J. 283 (1992) 75–80. [PMID: 1567380]
3.  Landry, J. and Sternglanz, R. Yeast Fms1 is a FAD-utilizing polyamine oxidase. Biochem. Biophys. Res. Commun. 303 (2003) 771–776. [PMID: 12670477]
[EC 1.5.3.17 created 2009]
 
 
EC 1.6.5.12     
Accepted name: demethylphylloquinone reductase
Reaction: demethylphylloquinone + NADPH + H+ = demethylphylloquinol + NADP+
Glossary: demethylphylloquinone = 2-phytyl-1,4-naphthoquinone
Other name(s): ndbB (gene name); NDC1 (gene name); demethylphylloquinone:NADPH oxidoreductase
Systematic name: NADPH:demethylphylloquinone oxidoreductase
Comments: The enzyme, found in plants and cyanobacteria, is involved in the biosynthesis of phylloquinone (vitamin K1), an electron carrier associated with photosystem I. The enzyme is a type II NADPH dehydrogenase and requires a flavine adenine dinucleotide cofactor.
References:
1.  Fatihi, A., Latimer, S., Schmollinger, S., Block, A., Dussault, P.H., Vermaas, W.F., Merchant, S.S. and Basset, G.J. A dedicated type II NADPH dehydrogenase performs the penultimate step in the biosynthesis of vitamin K1 in Synechocystis and Arabidopsis. Plant Cell 27 (2015) 1730–1741. [PMID: 26023160]
[EC 1.6.5.12 created 2015]
 
 
EC 1.7.1.4     
Accepted name: nitrite reductase [NAD(P)H]
Reaction: NH3 + 3 NAD(P)+ + 2 H2O = nitrite + 3 NAD(P)H + 5 H+
Other name(s): nitrite reductase (reduced nicotinamide adenine dinucleotide (phosphate)); assimilatory nitrite reductase (ambiguous); nitrite reductase [NAD(P)H2]; NAD(P)H2:nitrite oxidoreductase; nit-6 (gene name)
Systematic name: ammonia:NAD(P)+ oxidoreductase
Comments: An iron-sulfur flavoprotein (FAD) containing siroheme. The enzymes from the fungi Neurospora crassa [1], Emericella nidulans [2] and Candida nitratophila [4] can use either NADPH or NADH as electron donor. cf. EC 1.7.1.15, nitrite reductase (NADH).
References:
1.  Nicholas, D.J.D., Medina, A. and Jones, O.T.G. A nitrite reductase from Neurospora crassa. Biochim. Biophys. Acta 37 (1960) 468–476. [PMID: 14426899]
2.  Pateman, J.A., Rever, B.M. and Cove, D.J. Genetic and biochemical studies of nitrate reduction in Aspergillus nidulans. Biochem. J. 104 (1967) 103–111. [PMID: 4382427]
3.  Rivas, J., Guerrero, M. G., Paneque, A. and Losada, M. Characterization of the nitrate-reducing system of the yeast Torulopsis nitratophila. Plant Sci. Lett. 1 (1973) 105–113.
4.  Lafferty, M.A. and Garrett, R.H. Purification and properties of the Neurospora crassa assimilatory nitrite reductase. J. Biol. Chem. 249 (1974) 7555–7567. [PMID: 4154942]
5.  Vega, J.M. and Garrett, R.H. Siroheme: a prosthetic group of the Neurospora crassa assimilatory nitrite reductase. J. Biol. Chem. 250 (1975) 7980–7989. [PMID: 126995]
6.  Greenbaum, P., Prodouz, K.N. and Garrett, R.H. Preparation and some properties of homogeneous Neurospora crassa assimilatory NADPH-nitrite reductase. Biochim. Biophys. Acta 526 (1978) 52–64. [PMID: 150863]
7.  Prodouz, K.N. and Garrett, R.H. Neurospora crassa NAD(P)H-nitrite reductase. Studies on its composition and structure. J. Biol. Chem. 256 (1981) 9711–9717. [PMID: 6457037]
8.  Exley, G.E., Colandene, J.D. and Garrett, R.H. Molecular cloning, characterization, and nucleotide sequence of nit-6, the structural gene for nitrite reductase in Neurospora crassa. J. Bacteriol. 175 (1993) 2379–2392. [PMID: 8096840]
9.  Colandene, J.D. and Garrett, R.H. Functional dissection and site-directed mutagenesis of the structural gene for NAD(P)H-nitrite reductase in Neurospora crassa. J. Biol. Chem. 271 (1996) 24096–24104. [PMID: 8798648]
[EC 1.7.1.4 created 1961 as EC 1.6.6.4, transferred 2002 to EC 1.7.1.4, modified 2013]
 
 
EC 1.8.3.6     
Accepted name: farnesylcysteine lyase
Reaction: S-(2E,6E)-farnesyl-L-cysteine + O2 + H2O = (2E,6E)-farnesal + L-cysteine + H2O2
Other name(s): FC lyase; FCLY
Systematic name: S-(2E,6E)-farnesyl-L-cysteine oxidase
Comments: A flavoprotein (FAD). In contrast to mammalian EC 1.8.3.5 (prenylcysteine oxidase) the farnesylcysteine lyase from Arabidopsis is specific for S-farnesyl-L-cysteine and shows no activity with S-geranylgeranyl-L-cysteine.
References:
1.  Huizinga, D.H., Denton, R., Koehler, K.G., Tomasello, A., Wood, L., Sen, S.E. and Crowell, D.N. Farnesylcysteine lyase is involved in negative regulation of abscisic acid signaling in Arabidopsis. Mol Plant 3 (2010) 143–155. [PMID: 19969520]
2.  Crowell, D.N., Huizinga, D.H., Deem, A.K., Trobaugh, C., Denton, R. and Sen, S.E. Arabidopsis thaliana plants possess a specific farnesylcysteine lyase that is involved in detoxification and recycling of farnesylcysteine. Plant J. 50 (2007) 839–847. [PMID: 17425716]
[EC 1.8.3.6 created 2011]
 
 
EC 1.8.4.9     
Accepted name: adenylyl-sulfate reductase (glutathione)
Reaction: AMP + sulfite + glutathione disulfide = adenylyl sulfate + 2 glutathione
Other name(s): 5′-adenylylsulfate reductase (also used for EC 1.8.99.2); AMP,sulfite:oxidized-glutathione oxidoreductase (adenosine-5′-phosphosulfate-forming); plant-type 5′-adenylylsulfate reductase
Systematic name: AMP,sulfite:glutathione-disulfide oxidoreductase (adenosine-5′-phosphosulfate-forming)
Comments: This enzyme differs from EC 1.8.99.2, adenylyl-sulfate reductase, in using glutathione as the reductant. Glutathione can be replaced by γ-glutamylcysteine or dithiothreitol, but not by thioredoxin, glutaredoxin or 2-sulfanylethan-1-ol (2-mercaptoethanol). The enzyme from the mouseear cress, Arabidopsis thaliana, contains a glutaredoxin-like domain. The enzyme is also found in other photosynthetic eukaryotes, e.g., the Madagascar periwinkle, Catharanthus roseus and the hollow green seaweed, Ulva intestinalis.
References:
1.  Gutierrez-Marcos, J.F., Roberts, M.A., Campbell, E.I. and Wray, J.L. Three members of a novel small gene-family from Arabidopsis thaliana able to complement functionally an Escherichia coli mutant defective in PAPS reductase activity encode proteins with a thioredoxin-like domain and 'APS reductase' activity. Proc. Natl. Acad. Sci. USA 93 (1996) 13377–13382. [PMID: 8917599]
2.  Setya, A., Murillo, M. and Leustek, T. Sulfate reduction in higher plants: Molecular evidence for a novel 5-adenylylphosphosulfate (APS) reductase. Proc. Natl. Acad. Sci. USA 93 (1996) 13383–13388. [PMID: 8917600]
3.  Bick, J.A., Aslund, F., Cen, Y. and Leustek, T. Glutaredoxin function for the carboxyl-terminal domain of the plant-type 5′-adenylylsulfate reductase. Proc. Natl. Acad. Sci. USA 95 (1998) 8404–8409. [PMID: 9653199]
[EC 1.8.4.9 created 2000, modified 2002]
 
 
EC 1.8.7.1     
Accepted name: assimilatory sulfite reductase (ferredoxin)
Reaction: hydrogen sulfide + 6 oxidized ferredoxin [iron-sulfur] cluster + 3 H2O = sulfite + 6 reduced ferredoxin [iron-sulfur] cluster + 6 H+
Other name(s): ferredoxin-sulfite reductase; SIR (gene name); sulfite reductase (ferredoxin)
Systematic name: hydrogen-sulfide:ferredoxin oxidoreductase
Comments: An iron protein. The enzyme participates in sulfate assimilation. While it is usually found in cyanobacteria, plants and algae, it has also been reported in bacteria [4]. Different from EC 1.8.99.5, dissimilatory sulfite reductase, which is involved in prokaryotic sulfur-based energy metabolism. cf. EC 1.8.1.2, assimilatory sulfite reductase (NADPH).
References:
1.  Schmidt, A. and Trebst, A. The mechanism of photosynthetic sulfate reduction by isolated chloroplasts. Biochim. Biophys. Acta 180 (1969) 529–535. [PMID: 4390248]
2.  Gisselmann, G., Klausmeier, P. and Schwenn, J.D. The ferredoxin:sulphite reductase gene from Synechococcus PCC7942. Biochim. Biophys. Acta 1144 (1993) 102–106. [PMID: 8347657]
3.  Bork, C., Schwenn, J.D. and Hell, R. Isolation and characterization of a gene for assimilatory sulfite reductase from Arabidopsis thaliana. Gene 212 (1998) 147–153. [PMID: 9661674]
4.  Neumann, S., Wynen, A., Truper, H.G. and Dahl, C. Characterization of the cys gene locus from Allochromatium vinosum indicates an unusual sulfate assimilation pathway. Mol. Biol. Rep. 27 (2000) 27–33. [PMID: 10939523]
[EC 1.8.7.1 created 1972, modified 2015]
 
 
EC 1.10.3.11     
Accepted name: ubiquinol oxidase (non-electrogenic)
Reaction: 2 ubiquinol + O2 = 2 ubiquinone + 2 H2O
Other name(s): plant alternative oxidase; cyanide-insensitive oxidase; AOX (gene name); ubiquinol oxidase; ubiquinol:O2 oxidoreductase (non-electrogenic)
Systematic name: ubiquinol:oxygen oxidoreductase (non-electrogenic)
Comments: The enzyme, described from the mitochondria of plants and some fungi and protists, is an alternative terminal oxidase that is not sensitive to cyanide inhibition and does not generate a proton motive force. Unlike the electrogenic terminal oxidases that contain hemes (cf. EC 1.10.3.10 and EC 1.10.3.14), this enzyme contains a dinuclear non-heme iron complex. The function of this oxidase is believed to be dissipating excess reducing power, minimizing oxidative stress, and optimizing photosynthesis in response to changing conditions.
References:
1.  Bendall, D.S. and Bonner, W.D. Cyanide-insensitive respiration in plant mitochondria. Plant Physiol. 47 (1971) 236–245. [PMID: 16657603]
2.  Siedow, J.N., Umbach, A.L. and Moore, A.L. The active site of the cyanide-resistant oxidase from plant mitochondria contains a binuclear iron center. FEBS Lett. 362 (1995) 10–14. [PMID: 7698344]
3.  Berthold, D.A., Andersson, M.E. and Nordlund, P. New insight into the structure and function of the alternative oxidase. Biochim. Biophys. Acta 1460 (2000) 241–254. [PMID: 11106766]
4.  Williams, B.A., Elliot, C., Burri, L., Kido, Y., Kita, K., Moore, A.L. and Keeling, P.J. A broad distribution of the alternative oxidase in microsporidian parasites. PLoS Pathog. 6:e1000761 (2010). [PMID: 20169184]
5.  Gandin, A., Duffes, C., Day, D.A. and Cousins, A.B. The absence of alternative oxidase AOX1A results in altered response of photosynthetic carbon assimilation to increasing CO2 in Arabidopsis thaliana. Plant Cell Physiol. 53 (2012) 1627–1637. [PMID: 22848123]
[EC 1.10.3.11 created 2011, modified 2014]
 
 
EC 1.11.2.2     
Accepted name: myeloperoxidase
Reaction: Cl- + H2O2 + H+ = HClO + H2O
Other name(s): MPO; verdoperoxidase
Systematic name: chloride:hydrogen-peroxide oxidoreductase (hypochlorite-forming)
Comments: Contains calcium and covalently bound heme (proximal ligand histidine). It is present in phagosomes of neutrophils and monocytes, where the hypochlorite produced is strongly bactericidal. It differs from EC 1.11.1.10 chloride peroxidase in its preference for formation of hypochlorite over the chlorination of organic substrates under physiological conditions (pH 5-8). Hypochlorite in turn forms a number of antimicrobial products (Cl2, chloramines, hydroxyl radical, singlet oxygen). MPO also oxidizes bromide, iodide and thiocyanate. In the absence of halides, it oxidizes phenols and has a moderate peroxygenase activity toward styrene.
References:
1.  Agner, K. Myeloperoxidase. Adv. Enzymol. 3 (1943) 137–148.
2.  Harrison, J.E. and Schultz, J. Studies on the chlorinating activity of myeloperoxidase. J. Biol. Chem. 251 (1976) 1371–1374. [PMID: 176150]
3.  Furtmuller, P.G., Burner, U. and Obinger, C. Reaction of myeloperoxidase compound I with chloride, bromide, iodide, and thiocyanate. Biochemistry 37 (1998) 17923–17930. [PMID: 9922160]
4.  Tuynman, A., Spelberg, J.L., Kooter, I.M., Schoemaker, H.E. and Wever, R. Enantioselective epoxidation and carbon-carbon bond cleavage catalyzed by Coprinus cinereus peroxidase and myeloperoxidase. J. Biol. Chem. 275 (2000) 3025–3030. [PMID: 10652281]
5.  Klebanoff, S.J. Myeloperoxidase: friend and foe. J. Leukoc. Biol. 77 (2005) 598–625. [PMID: 15689384]
6.  Fiedler, T.J., Davey, C.A. and Fenna, R.E. X-ray crystal structure and characterization of halide-binding sites of human myeloperoxidase at 1.8 Å resolution. J. Biol. Chem. 275 (2000) 11964–11971. [PMID: 10766826]
7.  Gaut, J.P., Yeh, G.C., Tran, H.D., Byun, J., Henderson, J.P., Richter, G.M., Brennan, M.L., Lusis, A.J., Belaaouaj, A., Hotchkiss, R.S. and Heinecke, J.W. Neutrophils employ the myeloperoxidase system to generate antimicrobial brominating and chlorinating oxidants during sepsis. Proc. Natl. Acad. Sci. USA 98 (2001) 11961–11966. [PMID: 11593004]
[EC 1.11.2.2 created 2011]
 
 
EC 1.13.11.18     
Accepted name: persulfide dioxygenase
Reaction: S-sulfanylglutathione + O2 + H2O = glutathione + sulfite + 2 H+ (overall reaction)
(1a) S-sulfanylglutathione + O2 = S-sulfinatoglutathione + H+
(1b) S-sulfinatoglutathione + H2O = glutathione + sulfite + H+ (spontaneous)
Other name(s): sulfur oxygenase (incorrect); sulfur:oxygen oxidoreductase (incorrect); sulfur dioxygenase (incorrect)
Systematic name: S-sulfanylglutathione:oxygen oxidoreductase
Comments: An iron protein. Perthiols, formed spontaneously by interactions between thiols and elemental sulfur or sulfide, are the only acceptable substrate to the enzyme. The sulfite that is formed by the enzyme can be further converted into sulfate, thiosulfate or S-sulfoglutathione (GSSO3-) non-enzymically [2].
References:
1.  Suzuki, I. and Silver, M. The initial product and properties of the sulfur-oxidizing enzyme of thiobacilli. Biochim. Biophys. Acta 122 (1966) 22–33. [PMID: 5968172]
2.  Rohwerder, T. and Sand, W. The sulfane sulfur of persulfides is the actual substrate of the sulfur-oxidizing enzymes from Acidithiobacillus and Acidiphilium spp. Microbiology 149 (2003) 1699–1710. [PMID: 12855721]
3.  Liu, H., Xin, Y. and Xun, L. Distribution, diversity, and activities of sulfur dioxygenases in heterotrophic bacteria. Appl. Environ. Microbiol. 80 (2014) 1799–1806. [PMID: 24389926]
4.  Holdorf, M.M., Owen, H.A., Lieber, S.R., Yuan, L., Adams, N., Dabney-Smith, C. and Makaroff, C.A. Arabidopsis ETHE1 encodes a sulfur dioxygenase that is essential for embryo and endosperm development. Plant Physiol. 160 (2012) 226–236. [PMID: 22786886]
5.  Pettinati, I., Brem, J., McDonough, M.A. and Schofield, C.J. Crystal structure of human persulfide dioxygenase: structural basis of ethylmalonic encephalopathy. Hum. Mol. Genet. 24 (2015) 2458–2469. [PMID: 25596185]
[EC 1.13.11.18 created 1972, modified 2015]
 
 
EC 1.13.11.32      
Transferred entry: 2-nitropropane dioxygenase. Now EC 1.13.12.16, nitronate monooxygenase
[EC 1.13.11.32 created 1984, modified 2006, deleted 2009]
 
 
EC 1.13.11.51     
Accepted name: 9-cis-epoxycarotenoid dioxygenase
Reaction: (1) a 9-cis-epoxycarotenoid + O2 = 2-cis,4-trans-xanthoxin + a 12′-apo-carotenal
(2) 9-cis-violaxanthin + O2 = 2-cis,4-trans-xanthoxin + (3S,5R,6S)-5,6-epoxy-3-hydroxy-5,6-dihydro-12′-apo-β-caroten-12′-al
(3) 9′-cis-neoxanthin + O2 = 2-cis,4-trans-xanthoxin + (3S,5R,6R)-5,6-dihydroxy-6,7-didehydro-5,6-dihydro-12′-apo-β-caroten-12′-al
Other name(s): nine-cis-epoxycarotenoid dioxygenase; NCED; AtNCED3; PvNCED1; VP14
Systematic name: 9-cis-epoxycarotenoid 11,12-dioxygenase
Comments: Requires iron(II). Acts on 9-cis-violaxanthin and 9′-cis-neoxanthin but not on the all-trans isomers [2,3]. In vitro, it will cleave 9-cis-zeaxanthin. Catalyses the first step of abscisic-acid biosynthesis from carotenoids in chloroplasts, in response to water stress. The other enzymes involved in the abscisic-acid biosynthesis pathway are EC 1.1.1.288 (xanthoxin dehydrogenase), EC 1.2.3.14 (abscisic-aldehyde oxidase) and EC 1.14.13.93 [(+)-abscisic acid 8′-hydroxylase].
References:
1.  Schwartz, S.H., Tan, B.C., Gage, D.A., Zeevaart, J.A. and McCarty, D.R. Specific oxidative cleavage of carotenoids by VP14 of maize. Science 276 (1997) 1872–1874. [PMID: 9188535]
2.  Tan, B.C., Schwartz, S.H., Zeevaart, J.A. and McCarty, D.R. Genetic control of abscisic acid biosynthesis in maize. Proc. Natl. Acad. Sci. USA 94 (1997) 12235–12240. [PMID: 9342392]
3.  Qin, X. and Zeevaart, J.A. The 9-cis-epoxycarotenoid cleavage reaction is the key regulatory step of abscisic acid biosynthesis in water-stressed bean. Proc. Natl. Acad. Sci. USA 96 (1999) 15354–15361. [PMID: 10611388]
4.  Thompson, A.J., Jackson, A.C., Symonds, R.C., Mulholland, B.J., Dadswell, A.R., Blake, P.S., Burbidge, A. and Taylor, I.B. Ectopic expression of a tomato 9-cis-epoxycarotenoid dioxygenase gene causes over-production of abscisic acid. Plant J. 23 (2000) 363–374. [PMID: 10929129]
5.  Iuchi, S., Kobayashi, M., Taji, T., Naramoto, M., Seki, M., Kato, T., Tabata, S., Kakubari, Y., Yamaguchi-Shinozaki, K. and Shinozaki, K. Regulation of drought tolerance by gene manipulation of 9-cis-epoxycarotenoid dioxygenase, a key enzyme in abscisic acid biosynthesis in Arabidopsis. Plant J. 27 (2001) 325–333. [PMID: 11532178]
6.  Iuchi, S., Kobayashi, M., Taji, T., Naramoto, M., Seki, M., Kato, T., Tabata, S., Kakubari, Y., Yamaguchi-Shinozaki, K. and Shinozaki, K. Regulation of drought tolerance by gene manipulation of 9-cis-epoxycarotenoid dioxygenase, a key enzyme in abscisic acid biosynthesis in Arabidopsis. Plant J. 30 (2002) 611.
[EC 1.13.11.51 created 2005]
 
 
EC 1.13.11.58     
Accepted name: linoleate 9S-lipoxygenase
Reaction: linoleate + O2 = (9S,10E,12Z)-9-hydroperoxy-10,12-octadecadienoate
Glossary: linoleate = (9Z,12Z)-octadeca-9,12-dienoate
Other name(s): 9-lipoxygenase; 9S-lipoxygenase; linoleate 9-lipoxygenase; LOX1 (gene name); 9S-LOX
Systematic name: linoleate:oxygen 9S-oxidoreductase
Comments: Contains nonheme iron. A common plant lipoxygenase that oxidizes linoleate and α-linolenate, the two most common polyunsaturated fatty acids in plants, by inserting molecular oxygen at the C9 position with (S)-configuration. The enzyme plays a physiological role during the early stages of seedling growth. The enzyme from Arabidopsis thaliana shows comparable activity towards linoleate and linolenate [4]. EC 1.13.11.12 (linoleate 13S-lipoxygenase) catalyses a similar reaction at another position of these fatty acids.
References:
1.  Vellosillo, T., Martinez, M., Lopez, M.A., Vicente, J., Cascon, T., Dolan, L., Hamberg, M. and Castresana, C. Oxylipins produced by the 9-lipoxygenase pathway in Arabidopsis regulate lateral root development and defense responses through a specific signaling cascade. Plant Cell 19 (2007) 831–846. [PMID: 17369372]
2.  Boeglin, W.E., Itoh, A., Zheng, Y., Coffa, G., Howe, G.A. and Brash, A.R. Investigation of substrate binding and product stereochemistry issues in two linoleate 9-lipoxygenases. Lipids 43 (2008) 979–987. [PMID: 18795358]
3.  Andreou, A.Z., Hornung, E., Kunze, S., Rosahl, S. and Feussner, I. On the substrate binding of linoleate 9-lipoxygenases. Lipids 44 (2009) 207–215. [PMID: 19037675]
4.  Bannenberg, G., Martinez, M., Hamberg, M. and Castresana, C. Diversity of the enzymatic activity in the lipoxygenase gene family of Arabidopsis thaliana. Lipids 44 (2009) 85–95. [PMID: 18949503]
[EC 1.13.11.58 created 2011]
 
 
EC 1.13.11.59     
Accepted name: torulene dioxygenase
Reaction: torulene + O2 = 4′-apo-β,ψ-caroten-4′-al + 3-methylbut-2-enal
Glossary: torulene = 3′,4′-didehydro-β,ψ-carotene
Other name(s): CAO-2; CarT
Systematic name: torulene:oxygen oxidoreductase
Comments: It is assumed that 3-methylbut-2-enal is formed. The enzyme cannot cleave the saturated 3′,4′-bond of γ-carotene which implies that a 3′,4′-double bond is neccessary for this reaction.
References:
1.  Prado-Cabrero, A., Estrada, A.F., Al-Babili, S. and Avalos, J. Identification and biochemical characterization of a novel carotenoid oxygenase: elucidation of the cleavage step in the Fusarium carotenoid pathway. Mol. Microbiol. 64 (2007) 448–460. [PMID: 17493127]
2.  Saelices, L., Youssar, L., Holdermann, I., Al-Babili, S. and Avalos, J. Identification of the gene responsible for torulene cleavage in the Neurospora carotenoid pathway. Mol. Genet. Genomics 278 (2007) 527–537. [PMID: 17610084]
3.  Estrada, A.F., Maier, D., Scherzinger, D., Avalos, J. and Al-Babili, S. Novel apocarotenoid intermediates in Neurospora crassa mutants imply a new biosynthetic reaction sequence leading to neurosporaxanthin formation. Fungal Genet. Biol. 45 (2008) 1497–1505. [PMID: 18812228]
[EC 1.13.11.59 created 2011]
 
 
EC 1.13.11.63     
Accepted name: β-carotene 15,15′-dioxygenase
Reaction: β-carotene + O2 = 2 all-trans-retinal
Other name(s): blh (gene name); BCO1 (gene name); BCDO (gene name); carotene dioxygenase; carotene 15,15′-dioxygenase; BCMO1 (misleading); β-carotene 15,15′-monooxygenase (incorrect)
Systematic name: β-carotene:oxygen 15,15′-dioxygenase (bond-cleaving)
Comments: Requires Fe2+. The enzyme cleaves β-carotene symmetrically, producing two molecules of all-trans-retinal. Both atoms of the oxygen molecule are incorporated into the products [8]. The enzyme can also process β-cryptoxanthin, 8′-apo-β-carotenal, 4′-apo-β-carotenal, α-carotene and γ-carotene in decreasing order. The presence of at least one unsubstituted β-ionone ring in a substrate greater than C30 is mandatory [5]. A prokaryotic enzyme has been reported from the uncultured marine bacterium 66A03, where it is involved in the proteorhodopsin system, which uses retinal as its chromophore [6,7].
References:
1.  Goodman, D.S., Huang, H.S. and Shiratori, T. Mechanism of the biosynthesis of vitamin A from β-carotene. J. Biol. Chem. 241 (1966) 1929–1932. [PMID: 5946623]
2.  Goodman, D.S., Huang, H.S., Kanai, M. and Shiratori, T. The enzymatic conversion of all-trans β-carotene into retinal. J. Biol. Chem. 242 (1967) 3543–3554.
3.  Yan, W., Jang, G.F., Haeseleer, F., Esumi, N., Chang, J., Kerrigan, M., Campochiaro, M., Campochiaro, P., Palczewski, K. and Zack, D.J. Cloning and characterization of a human β,β-carotene-15,15′-dioxygenase that is highly expressed in the retinal pigment epithelium. Genomics 72 (2001) 193–202. [PMID: 11401432]
4.  Leuenberger, M.G., Engeloch-Jarret, C. and Woggon, W.D. The reaction mechanism of the enzyme-catalysed central cleavage of β-carotene to retinal. Angew. Chem. 40 (2001) 2614–2616. [PMID: 11458349]
5.  Kim, Y.S. and Oh, D.K. Substrate specificity of a recombinant chicken β-carotene 15,15′-monooxygenase that converts β-carotene into retinal. Biotechnol. Lett. 31 (2009) 403–408. [PMID: 18979213]
6.  Kim, Y.S., Kim, N.H., Yeom, S.J., Kim, S.W. and Oh, D.K. In vitro characterization of a recombinant Blh protein from an uncultured marine bacterium as a β-carotene 15,15′-dioxygenase. J. Biol. Chem. 284 (2009) 15781–15793. [PMID: 19366683]
7.  Kim, Y.S., Park, C.S. and Oh, D.K. Retinal production from β-carotene by β-carotene 15,15′-dioxygenase from an unculturable marine bacterium. Biotechnol. Lett. 32 (2010) 957–961. [PMID: 20229064]
8.  dela Seña, C., Riedl, K.M., Narayanasamy, S., Curley, R.W., Jr., Schwartz, S.J. and Harrison, E.H. The human enzyme that converts dietary provitamin A carotenoids to vitamin A is a dioxygenase. J. Biol. Chem. 289 (2014) 13661–13666. [PMID: 24668807]
[EC 1.13.11.63 created 2012 (EC 1.14.99.36 created 1972 as EC 1.13.11.21, transferred 2001 to EC 1.14.99.36, incorporated 2015), modified 2016]
 
 
EC 1.13.11.69     
Accepted name: carlactone synthase
Reaction: 9-cis-10′-apo-β-carotenal + 2 O2 = carlactone + (2E,4E,6E)-7-hydroxy-4-methylhepta-2,4,6-trienal
Glossary: carlactone = 3-methyl-5-{[(1Z,3E)-2-methyl-4-(2,6,6-trimethylcyclohex-1-en-1-yl)buta-1,3-dien-1-yl]oxy}-5H-furan-2-one
Other name(s): CCD8 (gene name); MAX4 (gene name); NCED8 (gene name)
Systematic name: 9-cis-10′-apo-β-carotenal:oxygen oxidoreductase (14,15-cleaving, carlactone-forming)
Comments: Requires Fe2+. The enzyme participates in a pathway leading to biosynthesis of strigolactones, plant hormones involved in promotion of symbiotic associations known as arbuscular mycorrhiza. Also catalyses EC 1.13.11.70, all-trans-10′-apo-β-carotenal 13,14-cleaving dioxygenase, but 10-fold slower.
References:
1.  Sorefan, K., Booker, J., Haurogne, K., Goussot, M., Bainbridge, K., Foo, E., Chatfield, S., Ward, S., Beveridge, C., Rameau, C. and Leyser, O. MAX4 and RMS1 are orthologous dioxygenase-like genes that regulate shoot branching in Arabidopsis and pea. Genes Dev. 17 (2003) 1469–1474. [PMID: 12815068]
2.  Schwartz, S.H., Qin, X. and Loewen, M.C. The biochemical characterization of two carotenoid cleavage enzymes from Arabidopsis indicates that a carotenoid-derived compound inhibits lateral branching. J. Biol. Chem. 279 (2004) 46940–46945. [PMID: 15342640]
3.  Alder, A., Jamil, M., Marzorati, M., Bruno, M., Vermathen, M., Bigler, P., Ghisla, S., Bouwmeester, H., Beyer, P. and Al-Babili, S. The path from β-carotene to carlactone, a strigolactone-like plant hormone. Science 335 (2012) 1348–1351. [PMID: 22422982]
[EC 1.13.11.69 created 2012]
 
 
EC 1.13.11.70     
Accepted name: all-trans-10′-apo-β-carotenal 13,14-cleaving dioxygenase
Reaction: all-trans-10′-apo-β-carotenal + O2 = 13-apo-β-carotenone + (2E,4E,6E)-4-methylocta-2,4,6-trienedial
Other name(s): CCD8 (gene name); MAX4 (gene name); NCED8 (gene name); all-trans-10′-apo-β-carotenal:O2 oxidoreductase (13,14-cleaving)
Systematic name: all-trans-10′-apo-β-carotenal:oxygen oxidoreductase (13,14-cleaving)
Comments: Requires Fe2+. The enzyme from the plant Arabidopsis thaliana also catalyses EC 1.13.11.69, carlactone synthase, 10-fold faster.
References:
1.  Schwartz, S.H., Qin, X. and Loewen, M.C. The biochemical characterization of two carotenoid cleavage enzymes from Arabidopsis indicates that a carotenoid-derived compound inhibits lateral branching. J. Biol. Chem. 279 (2004) 46940–46945. [PMID: 15342640]
[EC 1.13.11.70 created 2012]
 
 
EC 1.13.11.80     
Accepted name: (3,5-dihydroxyphenyl)acetyl-CoA 1,2-dioxygenase
Reaction: (3,5-dihydroxyphenyl)acetyl-CoA + O2 = 2-(3,5-dihydroxyphenyl)-2-oxoacetate + CoA
Glossary: (3,5-dihydroxyphenyl)acetyl-CoA = 2-(3,5-dihydroxyphenyl)acetyl-CoA
Other name(s): DpgC
Systematic name: (3,5-dihydroxyphenyl)acetyl-CoA:oxygen oxidoreductase
Comments: The enzyme, characterized from bacteria Streptomyces toyocaensis and Amycolatopsis orientalis, is involved in the biosynthesis of (3,5-dihydroxyphenyl)glycine, a component of the glycopeptide antibiotic vancomycin.
References:
1.  Chen, H., Tseng, C.C., Hubbard, B.K. and Walsh, C.T. Glycopeptide antibiotic biosynthesis: enzymatic assembly of the dedicated amino acid monomer (S)-3,5-dihydroxyphenylglycine. Proc. Natl. Acad. Sci. USA 98 (2001) 14901–14906. [PMID: 11752437]
2.  Widboom, P.F., Fielding, E.N., Liu, Y. and Bruner, S.D. Structural basis for cofactor-independent dioxygenation in vancomycin biosynthesis. Nature 447 (2007) 342–345. [PMID: 17507985]
3.  Fielding, E.N., Widboom, P.F. and Bruner, S.D. Substrate recognition and catalysis by the cofactor-independent dioxygenase DpgC. Biochemistry 46 (2007) 13994–14000. [PMID: 18004875]
[EC 1.13.11.80 created 2015]
 
 
EC 1.13.11.92     
Accepted name: fatty acid α-dioxygenase
Reaction: a fatty acid + O2 = a (2R)-2-hydroperoxyfatty acid
Other name(s): DOX1 (gene name)
Systematic name: fatty acid:oxygen 2-oxidoreductase [(2R)-2-hydroperoxyfatty acid-forming]
Comments: Contains heme. This plant enzyme catalyses the (2R)-hydroperoxidation of fatty acids. It differs from lipoxygenases and cyclooxygenases in that the oxygen addition does not target an unsaturated region in the fatty acid. In vitro the product undergoes spontaneous decarboxylation, resulting in formation of a chain-shortened aldehyde. In vivo the product may be reduced to a (2R)-2-hydroxyfatty acid. The enzyme, which is involved in responses to different abiotic and biotic stresses, has a wide substrate range that includes both saturated and unsaturated fatty acids.
References:
1.  Akakabe, Y., Matsui, K., and Kajiwara, T. Enantioselective α-hydroperoxylation of long-chain fatty acids with crude enzyme of marine green alga Ulva pertusa. Tetrahedron Lett. 40 (1999) 1137–1140.
2.  Hamberg, M., Sanz, A. and Castresana, C. α-oxidation of fatty acids in higher plants. Identification of a pathogen-inducible oxygenase (piox) as an α-dioxygenase and biosynthesis of 2-hydroperoxylinolenic acid. J. Biol. Chem. 274 (1999) 24503–24513. [PMID: 10455113]
3.  Saffert, A., Hartmann-Schreier, J., Schon, A. and Schreier, P. A dual function α-dioxygenase-peroxidase and NAD(+) oxidoreductase active enzyme from germinating pea rationalizing α-oxidation of fatty acids in plants. Plant Physiol. 123 (2000) 1545–1552. [PMID: 10938370]
4.  Koeduka, T., Matsui, K., Akakabe, Y. and Kajiwara, T. Catalytic properties of rice α-oxygenase. A comparison with mammalian prostaglandin H synthases. J. Biol. Chem. 277 (2002) 22648–22655. [PMID: 11909851]
5.  Liu, W., Rogge, C.E., Bambai, B., Palmer, G., Tsai, A.L. and Kulmacz, R.J. Characterization of the heme environment in Arabidopsis thaliana fatty acid α-dioxygenase-1. J. Biol. Chem. 279 (2004) 29805–29815. [PMID: 15100225]
6.  Meisner, A.K., Saffert, A., Schreier, P. and Schon, A. Fatty acid α-dioxygenase from Pisum sativum: temporal and spatial regulation during germination and plant development. J. Plant Physiol. 166 (2009) 333–343. [PMID: 18760499]
[EC 1.13.11.92 created 2021]
 
 
EC 1.13.12.5     
Accepted name: Renilla-type luciferase
Reaction: coelenterazine h + O2 = excited coelenteramide h monoanion + CO2 (over-all reaction)
(1a) coelenterazine h + O2 = coelenterazine h dioxetanone
(1b) coelenterazine h dioxetanone = excited coelenteramide h monoanion + CO2
Glossary: coelenterazine h = Renilla luciferin = 2,8-dibenzyl-6-(4-hydroxyphenyl)imidazo[1,2-a]pyrazin-3(7H)-one
coelenteramide h = Renilla oxyluciferin = N-[3-benzyl-5-(4-hydroxyphenyl)pyrazin-2-yl]-2-phenylacetamide
Other name(s): Renilla-luciferin 2-monooxygenase; luciferase (Renilla luciferin); Renilla-luciferin:oxygen 2-oxidoreductase (decarboxylating)
Systematic name: coelenterazine h:oxygen 2-oxidoreductase (decarboxylating)
Comments: This enzyme has been studied from the soft coral Renilla reniformis. Before the reaction occurs the substrate is sequestered by a coelenterazine-binding protein. Elevation in the concentration of calcium ions releases the substrate, which then interacts with the luciferase. Upon binding the substrate, the enzyme catalyses an oxygenation, producing a very short-lived hydroperoxide that cyclizes into a dioxetanone structure, which collapses, releasing a CO2 molecule. The spontaneous breakdown of the dioxetanone releases the energy (about 50 kcal/mole) that is necessary to generate the excited state of the coelenteramide product, which is the singlet form of the monoanion. In vivo the product undergoes the process of nonradiative energy transfer to an accessory protein, a green fluorescent protein (GFP), which results in green bioluminescence. In vitro, in the absence of GFP, the product emits blue light.
References:
1.  Cormier, M.J., Hori, K. and Anderson, J.M. Bioluminescence in coelenterates. Biochim. Biophys. Acta 346 (1974) 137–164. [PMID: 4154104]
2.  Hori, K., Anderson, J.M., Ward, W.W. and Cormier, M.J. Renilla luciferin as the substrate for calcium induced photoprotein bioluminescence. Assignment of luciferin tautomers in aequorin and mnemiopsin. Biochemistry 14 (1975) 2371–2376. [PMID: 237531]
3.  Anderson, J.M., Charbonneau, H. and Cormier, M.J. Mechanism of calcium induction of Renilla bioluminescence. Involvement of a calcium-triggered luciferin binding protein. Biochemistry 13 (1974) 1195–1200. [PMID: 4149963]
4.  Shimomura, O. and Johnson, F.H. Chemical nature of bioluminescence systems in coelenterates. Proc. Natl. Acad. Sci. USA 72 (1975) 1546–1549. [PMID: 236561]
5.  Charbonneau, H. and Cormier, M.J. Ca2+-induced bioluminescence in Renilla reniformis. Purification and characterization of a calcium-triggered luciferin-binding protein. J. Biol. Chem. 254 (1979) 769–780. [PMID: 33174]
6.  Lorenz, W.W., McCann, R.O., Longiaru, M. and Cormier, M.J. Isolation and expression of a cDNA encoding Renilla reniformis luciferase. Proc. Natl. Acad. Sci. USA 88 (1991) 4438–4442. [PMID: 1674607]
7.  Loening, A.M., Fenn, T.D. and Gambhir, S.S. Crystal structures of the luciferase and green fluorescent protein from Renilla reniformis. J. Mol. Biol. 374 (2007) 1017–1028. [PMID: 17980388]
[EC 1.13.12.5 created 1976, modified 1981, modified 1982, modified 2004, modified 2017]
 
 
EC 1.13.12.14      
Transferred entry: chlorophyllide-a oxygenase. Now EC 1.14.13.122, chlorophyllide-a oxygenase
[EC 1.13.12.14 created 2006, deleted 2011]
 
 
EC 1.13.12.16     
Accepted name: nitronate monooxygenase
Reaction: ethylnitronate + O2 = acetaldehyde + nitrite + other products
Other name(s): NMO; 2-nitropropane dioxygenase (incorrect)
Systematic name: nitronate:oxygen 2-oxidoreductase (nitrite-forming)
Comments: Previously classified as 2-nitropropane dioxygenase (EC 1.13.11.32), but it is now recognized that this was the result of the slow ionization of nitroalkanes to their nitronate (anionic) forms. The enzymes from the fungus Neurospora crassa and the yeast Williopsis saturnus var. mrakii (formerly classified as Hansenula mrakii) contain non-covalently bound FMN as the cofactor. Neither hydrogen peroxide nor superoxide were detected during enzyme turnover. Active towards linear alkyl nitronates of lengths between 2 and 6 carbon atoms and, with lower activity, towards propyl-2-nitronate. The enzyme from N. crassa can also utilize neutral nitroalkanes, but with lower activity.
References:
1.  Francis, K., Russell, B. and Gadda, G. Involvement of a flavosemiquinone in the enzymatic oxidation of nitroalkanes catalyzed by 2-nitropropane dioxygenase. J. Biol. Chem. 280 (2005) 5195–5204. [PMID: 15582992]
2.  Ha, J.Y., Min, J.Y., Lee, S.K., Kim, H.S., Kim do, J., Kim, K.H., Lee, H.H., Kim, H.K., Yoon, H.J. and Suh, S.W. Crystal structure of 2-nitropropane dioxygenase complexed with FMN and substrate. Identification of the catalytic base. J. Biol. Chem. 281 (2006) 18660–18667. [PMID: 16682407]
3.  Gadda, G. and Francis, K. Nitronate monooxygenase, a model for anionic flavin semiquinone intermediates in oxidative catalysis. Arch. Biochem. Biophys. 493 (2010) 53–61. [PMID: 19577534]
4.  Francis, K. and Gadda, G. Kinetic evidence for an anion binding pocket in the active site of nitronate monooxygenase. Bioorg. Chem. 37 (2009) 167–172. [PMID: 19683782]
[EC 1.13.12.16 created 1984 as EC 1.13.11.32, transferred 2009 to EC 1.13.12.16, modified 2011]
 
 
EC 1.13.12.24     
Accepted name: calcium-regulated photoprotein
Reaction: [apoaequorin] + coelenterazine + O2 + 3 Ca2+ = [excited state blue fluorescent protein] + CO2 (overall reaction)
(1a) [apoaequorin] + coelenterazine = [apoaequorin containing coelenterazine]
(1b) [apoaequorin containing coelenterazine] + O2 = [aequorin]
(1c) [aequorin] + 3 Ca2+ = [aequorin] 1,2-dioxetan-3-one
(1d) [aequorin] 1,2-dioxetan-3-one = [excited state blue fluorescent protein] + CO2
Glossary: coelenterazine = 8-benzyl-2-(4-hydroxybenzyl)-6-(4-hydroxyphenyl)imidazo[1,2-a]pyrazin-3(7H)-one
coelenteramide = N-[3-benzyl-5-(4-hydroxyphenyl)pyrazin-2-yl]-2-(4-hydroxyphenyl)acetamide
aequorin = the non-covalent complex formed by apoaequorin polypeptide and coelenterazine-2-hydroperoxide.
blue fluorescent protein = the non-covalent complex formed by Ca2+-bound apoaequorin polypeptide and coelenteramide
Other name(s): Ca2+-regulated photoprotein; calcium-activated photoprotein; aequorin; obelin; halistaurin; mitrocomin; phialidin; clytin; mnemiopsin; berovin
Systematic name: coelenterazine:oxygen 2-oxidoreductase (decarboxylating, calcium-dependent)
Comments: Ca2+-regulated photoproteins are found in a variety of bioluminescent marine organisms, mostly coelenterates, and are responsible for their light emission. The best studied enzyme is from the jellyfish Aequorea victoria. The enzyme tightly binds the imidazolopyrazinone derivative coelenterazine, which is then peroxidized by oxygen. The hydroperoxide is stably bound until three Ca2+ ions bind to the protein, inducing a structural change that results in the formation of a 1,2-dioxetan-3-one ring, followed by decarboxylation and generation of a protein-bound coelenteramide in an excited state. The calcium-bound protein-product complex is known as a blue fluorescent protein. In vivo the energy is transferred to a green fluorescent protein (GFP) by Förster resonance energy transfer. In vitro, in the absence of GFP, coelenteramide emits a photon of blue light while returning to its ground state.
References:
1.  Shimomura, O., Johnson, F. H., and Saiga, Y. Purification and properties of aequorin, a bio-(chemi-) luminescent protein from the jellyfish, Aequorea aequorea. Fed. Proc. 21 (1962) 401.
2.  Morise, H., Shimomura, O., Johnson, F.H. and Winant, J. Intermolecular energy transfer in the bioluminescent system of Aequorea. Biochemistry 13 (1974) 2656–2662. [PMID: 4151620]
3.  Inouye, S., Noguchi, M., Sakaki, Y., Takagi, Y., Miyata, T., Iwanaga, S., Miyata, T. and Tsuji, F.I. Cloning and sequence analysis of cDNA for the luminescent protein aequorin. Proc. Natl. Acad. Sci. USA 82 (1985) 3154–3158. [PMID: 3858813]
4.  Head, J.F., Inouye, S., Teranishi, K. and Shimomura, O. The crystal structure of the photoprotein aequorin at 2.3 Å resolution. Nature 405 (2000) 372–376. [PMID: 10830969]
5.  Deng, L., Vysotski, E.S., Markova, S.V., Liu, Z.J., Lee, J., Rose, J. and Wang, B.C. All three Ca2+-binding loops of photoproteins bind calcium ions: the crystal structures of calcium-loaded apo-aequorin and apo-obelin. Protein Sci. 14 (2005) 663–675. [PMID: 15689515]
[EC 1.13.12.24 created 2018]
 
 
EC 1.14.11.8     
Accepted name: trimethyllysine dioxygenase
Reaction: N6,N6,N6-trimethyl-L-lysine + 2-oxoglutarate + O2 = (3S)-3-hydroxy-N6,N6,N6-trimethyl-L-lysine + succinate + CO2
Other name(s): trimethyllysine α-ketoglutarate dioxygenase; TML-α-ketoglutarate dioxygenase; TML hydroxylase; 6-N,6-N,6-N-trimethyl-L-lysine,2-oxoglutarate:oxygen oxidoreductase (3-hydroxylating)
Systematic name: N6,N6,N6-trimethyl-L-lysine,2-oxoglutarate:oxygen oxidoreductase (3-hydroxylating)
Comments: Requires Fe2+ and ascorbate.
References:
1.  Hulse, J.D., Ellis, S.R. and Henderson, L.M. Carnitine biosynthesis. β-Hydroxylation of trimethyllysine by an α-ketoglutarate-dependent mitochondrial dioxygenase. J. Biol. Chem. 253 (1978) 1654–1659. [PMID: 627563]
2.  Al Temimi, A.H., Pieters, B.J., Reddy, Y.V., White, P.B. and Mecinovic, J. Substrate scope for trimethyllysine hydroxylase catalysis. Chem. Commun. (Camb.) 52 (2016) 12849–12852. [PMID: 27730239]
3.  Lesniak, R.K., Markolovic, S., Tars, K. and Schofield, C.J. Human carnitine biosynthesis proceeds via (2S,3S)-3-hydroxy-Nε-trimethyllysine. Chem. Commun. (Camb.) 53 (2016) 440–442. [PMID: 27965989]
4.  Reddy, Y.V., Al Temimi, A.H., White, P.B. and Mecinovic, J. Evidence that trimethyllysine hydroxylase catalyzes the formation of (2S,3S)-3-hydroxy-Nε-trimethyllysine. Org. Lett. 19 (2017) 400–403. [PMID: 28045275]
[EC 1.14.11.8 created 1983]
 
 
EC 1.14.11.9     
Accepted name: flavanone 3-dioxygenase
Reaction: a (2S)-flavan-4-one + 2-oxoglutarate + O2 = a (2R,3R)-dihydroflavonol + succinate + CO2
Other name(s): naringenin 3-hydroxylase; flavanone 3-hydroxylase; flavanone 3β-hydroxylase; flavanone synthase I; (2S)-flavanone 3-hydroxylase; naringenin,2-oxoglutarate:oxygen oxidoreductase (3-hydroxylating); F3H; flavanone,2-oxoglutarate:oxygen oxidoreductase (3-hydroxylating)
Systematic name: (2S)-flavan-4-one,2-oxoglutarate:oxygen oxidoreductase (3-hydroxylating)
Comments: Requires Fe2+ and ascorbate. This plant enzyme catalyses an early step in the flavonoid biosynthesis pathway, leading to the production of flavanols and anthocyanins. Substrates include (2S)-naringenin, (2S)-eriodictyol, (2S)-dihydrotricetin and (2S)-pinocembrin. Some enzymes are bifuctional and also catalyse EC 1.14.20.6, flavonol synthase.
References:
1.  Forkmann, G., Heller, W. and Grisebach, H. Anthocyanin biosynthesis in flowers of Matthiola incana flavanone 3- and flavonoid 3′-hydroxylases. Z. Naturforsch. C: Biosci. 35 (1980) 691–695.
2.  Charrier, B., Coronado, C., Kondorosi, A. and Ratet, P. Molecular characterization and expression of alfalfa (Medicago sativa L.) flavanone-3-hydroxylase and dihydroflavonol-4-reductase encoding genes. Plant Mol. Biol. 29 (1995) 773–786. [PMID: 8541503]
3.  Pelletier, M.K. and Shirley, B.W. Analysis of flavanone 3-hydroxylase in Arabidopsis seedlings. Coordinate regulation with chalcone synthase and chalcone isomerase. Plant Physiol. 111 (1996) 339–345. [PMID: 8685272]
4.  Wellmann, F., Matern, U. and Lukačin, R. Significance of C-terminal sequence elements for Petunia flavanone 3β-hydroxylase activity. FEBS Lett. 561 (2004) 149–154. [PMID: 15013767]
5.  Jin, Z., Grotewold, E., Qu, W., Fu, G. and Zhao, D. Cloning and characterization of a flavanone 3-hydroxylase gene from Saussurea medusa. DNA Seq 16 (2005) 121–129. [PMID: 16147863]
6.  Shen, G., Pang, Y., Wu, W., Deng, Z., Zhao, L., Cao, Y., Sun, X. and Tang, K. Cloning and characterization of a flavanone 3-hydroxylase gene from Ginkgo biloba. Biosci Rep 26 (2006) 19–29. [PMID: 16779664]
[EC 1.14.11.9 created 1983, modified 1989, modified 2004, modified 2016]
 
 
EC 1.14.11.19      
Transferred entry: anthocyanidin synthase. Now EC 1.14.20.4, anthocyanidin synthase
[EC 1.14.11.19 created 2001, modified 2017, deleted 2018]
 
 
EC 1.14.11.60     
Accepted name: scopoletin 8-hydroxylase
Reaction: scopoletin + 2-oxoglutarate + O2 = fraxetin + succinate + CO2
Glossary: fraxetin = 7,8-dihydroxy-6-methoxy-2H-chromen-2-one
scopoletin = 7-hydroxy-6-methoxy-2H-chromen-2-one
Other name(s): S8H (gene name)
Systematic name: scopoletin,2-oxoglutarate:oxygen oxidoreductase (8-hydroxylating)
Comments: Requires iron(II) and ascorbate. A protein involved in biosynthesis of iron(III)-chelating coumarins in higher plants.
References:
1.  Siwinska, J., Siatkowska, K., Olry, A., Grosjean, J., Hehn, A., Bourgaud, F., Meharg, A.A., Carey, M., Lojkowska, E. and Ihnatowicz, A. Scopoletin 8-hydroxylase: a novel enzyme involved in coumarin biosynthesis and iron-deficiency responses in Arabidopsis. J. Exp. Bot. 69 (2018) 1735–1748. [PMID: 29361149]
2.  Rajniak, J., Giehl, R.FH., Chang, E., Murgia, I., von Wiren, N. and Sattely, E.S. Biosynthesis of redox-active metabolites in response to iron deficiency in plants. Nat. Chem. Biol. 14 (2018) 442–450. [PMID: 29581584]
[EC 1.14.11.60 created 2018]
 
 
EC 1.14.11.61     
Accepted name: feruloyl-CoA 6-hydroxylase
Reaction: trans-feruloyl-CoA + 2-oxoglutarate + O2 = trans-6-hydroxyferuloyl-CoA + succinate + CO2
Glossary: trans-feruloyl-CoA = 4-hydroxy-3-methoxycinnamoyl-CoA = (E)-3-(4-hydroxy-3-methoxyphenyl)propenoyl-CoA
Systematic name: feruloyl-CoA,2-oxoglutarate:oxygen oxidoreductase (6-hydroxylating)
Comments: Requires iron(II) and ascorbate. The product spontaneously undergoes trans-cis isomerization and lactonization to form scopoletin, liberating CoA in the process. The enzymes from the plants Ruta graveolens and Ipomoea batatas also act on trans-4-coumaroyl-CoA. cf. EC 1.14.11.62, trans-4-coumaroyl-CoA 2-hydroxylase.
References:
1.  Kai, K., Mizutani, M., Kawamura, N., Yamamoto, R., Tamai, M., Yamaguchi, H., Sakata, K. and Shimizu, B. Scopoletin is biosynthesized via ortho-hydroxylation of feruloyl CoA by a 2-oxoglutarate-dependent dioxygenase in Arabidopsis thaliana. Plant J. 55 (2008) 989–999. [PMID: 18547395]
2.  Bayoumi, S.A., Rowan, M.G., Blagbrough, I.S. and Beeching, J.R. Biosynthesis of scopoletin and scopolin in cassava roots during post-harvest physiological deterioration: the E-Z-isomerisation stage. Phytochemistry 69 (2008) 2928–2936. [PMID: 19004461]
3.  Vialart, G., Hehn, A., Olry, A., Ito, K., Krieger, C., Larbat, R., Paris, C., Shimizu, B., Sugimoto, Y., Mizutani, M. and Bourgaud, F. A 2-oxoglutarate-dependent dioxygenase from Ruta graveolens L. exhibits p-coumaroyl CoA 2′-hydroxylase activity (C2′H): a missing step in the synthesis of umbelliferone in plants. Plant J. 70 (2012) 460–470. [PMID: 22168819]
4.  Matsumoto, S., Mizutani, M., Sakata, K. and Shimizu, B. Molecular cloning and functional analysis of the ortho-hydroxylases of p-coumaroyl coenzyme A/feruloyl coenzyme A involved in formation of umbelliferone and scopoletin in sweet potato, Ipomoea batatas (L.) Lam. Phytochemistry 74 (2012) 49–57. [PMID: 22169019]
[EC 1.14.11.61 created 2019]
 
 
EC 1.14.11.66     
Accepted name: [histone H3]-trimethyl-L-lysine9 demethylase
Reaction: a [histone H3]-N6,N6,N6-trimethyl-L-lysine9 + 2 2-oxoglutarate + 2 O2 = a [histone H3]-N6-methyl-L-lysine9 + 2 succinate + 2 formaldehyde + 2 CO2 (overall reaction)
(1a) a [histone H3]-N6,N6,N6-trimethyl-L-lysine9 + 2-oxoglutarate + O2 = a [histone H3]-N6,N6-dimethyl-L-lysine9 + succinate + formaldehyde + CO2
(1b) a [histone H3]-N6,N6-dimethyl-L-lysine9 + 2-oxoglutarate + O2 = a [histone H3]-N6-methyl-L-lysine9 + succinate + formaldehyde + CO2
Other name(s): KDM4A (gene name); KDM4B (gene name); KDM4C (gene name); KDM4D (gene name); JHDM3A (gene name); JMJD2 (gene name); JMJD2A (gene name); GASC1 (gene name)
Systematic name: [histone H3]-N6,N6,N6-trimethyl-L-lysine9,2-oxoglutarate:oxygen oxidoreductase
Comments: Requires iron(II). This entry describes a group of enzymes that demethylate N-methylated Lys-9 residues in the tail of the histone protein H3 (H3K9). This lysine residue can exist in three methylation states (mono-, di- and trimethylated), but this group of enzymes only act on the the tri- and di-methylated forms. The enzymes are dioxygenases and act by hydroxylating the methyl group, forming an unstable hemiaminal that leaves as formaldehyde. cf. EC 1.14.11.65, [histone H3]-dimethyl-L-lysine9 demethylase.
References:
1.  Cloos, P.A., Christensen, J., Agger, K., Maiolica, A., Rappsilber, J., Antal, T., Hansen, K.H. and Helin, K. The putative oncogene GASC1 demethylates tri- and dimethylated lysine 9 on histone H3. Nature 442 (2006) 307–311. [PMID: 16732293]
2.  Fodor, B.D., Kubicek, S., Yonezawa, M., O'Sullivan, R.J., Sengupta, R., Perez-Burgos, L., Opravil, S., Mechtler, K., Schotta, G. and Jenuwein, T. Jmjd2b antagonizes H3K9 trimethylation at pericentric heterochromatin in mammalian cells. Genes Dev. 20 (2006) 1557–1562. [PMID: 16738407]
3.  Klose, R.J., Yamane, K., Bae, Y., Zhang, D., Erdjument-Bromage, H., Tempst, P., Wong, J. and Zhang, Y. The transcriptional repressor JHDM3A demethylates trimethyl histone H3 lysine 9 and lysine 36. Nature 442 (2006) 312–316. [PMID: 16732292]
4.  Whetstine, J.R., Nottke, A., Lan, F., Huarte, M., Smolikov, S., Chen, Z., Spooner, E., Li, E., Zhang, G., Colaiacovo, M. and Shi, Y. Reversal of histone lysine trimethylation by the JMJD2 family of histone demethylases. Cell 125 (2006) 467–481. [PMID: 16603238]
[EC 1.14.11.66 created 2019]
 
 
EC 1.14.11.67     
Accepted name: [histone H3]-trimethyl-L-lysine4 demethylase
Reaction: a [histone H3]-N6,N6,N6-trimethyl-L-lysine4 + 3 2-oxoglutarate + 3 O2 = a [histone H3]-L-lysine4 + 3 succinate + 3 formaldehyde + 3 CO2 (overall reaction)
(1a) a [histone H3]-N6,N6,N6-trimethyl-L-lysine4 + 2-oxoglutarate + O2 = a [histone H3]-N6,N6-dimethyl-L-lysine4 + succinate + formaldehyde + CO2
(1b) a [histone H3]-N6,N6-dimethyl-L-lysine4 + 2-oxoglutarate + O2 = a [histone H3]-N6-methyl-L-lysine4 + succinate + formaldehyde + CO2
(1c) a [histone H3]-N6-methyl-L-lysine4 + 2-oxoglutarate + O2 = a [histone H3]-L-lysine4 + succinate + formaldehyde + CO2
Other name(s): KDM5A (gene name); KDM5B (gene name); KDM5C (gene name); KDM5D (gene name); JARID1A (gene name)
Systematic name: [histone H3]-N6,N6,N6-trimethyl-L-lysine4,2-oxoglutarate:oxygen oxidoreductase
Comments: Requires iron(II). This entry describes a group of enzymes that demethylate N-methylated L-lysine residues at position 4 of histone H3 (H3K4). The enzymes are dioxygenases and act by hydroxylating the methyl group, forming an unstable hemiaminal that leaves as formaldehyde. They can act on tri-, di-, and mono-methylated forms.
References:
1.  Seward, D.J., Cubberley, G., Kim, S., Schonewald, M., Zhang, L., Tripet, B. and Bentley, D.L. Demethylation of trimethylated histone H3 Lys4 in vivo by JARID1 JmjC proteins. Nat. Struct. Mol. Biol. 14 (2007) 240–242. [PMID: 17310255]
2.  Klose, R.J., Yan, Q., Tothova, Z., Yamane, K., Erdjument-Bromage, H., Tempst, P., Gilliland, D.G., Zhang, Y. and Kaelin, W.G., Jr. The retinoblastoma binding protein RBP2 is an H3K4 demethylase. Cell 128 (2007) 889–900. [PMID: 17320163]
3.  Iwase, S., Lan, F., Bayliss, P., de la Torre-Ubieta, L., Huarte, M., Qi, H.H., Whetstine, J.R., Bonni, A., Roberts, T.M. and Shi, Y. The X-linked mental retardation gene SMCX/JARID1C defines a family of histone H3 lysine 4 demethylases. Cell 128 (2007) 1077–1088. [PMID: 17320160]
4.  Christensen, J., Agger, K., Cloos, P.A., Pasini, D., Rose, S., Sennels, L., Rappsilber, J., Hansen, K.H., Salcini, A.E. and Helin, K. RBP2 belongs to a family of demethylases, specific for tri-and dimethylated lysine 4 on histone 3. Cell 128 (2007) 1063–1076. [PMID: 17320161]
[EC 1.14.11.67 created 2019]
 
 
EC 1.14.11.70     
Accepted name: 7-deoxycylindrospermopsin hydroxylase
Reaction: (1) 7-deoxycylindrospermopsin + 2-oxoglutarate + O2 = cylindrospermopsin + succinate + CO2
(2) 7-deoxycylindrospermopsin + 2-oxoglutarate + O2 = 7-epi-cylindrospermopsin + succinate + CO2
Glossary: cylindrospermopsin = (2aS,3R,4S,5aS,7R)-7-[(R)-(2,6-dioxo-1,2,3,6-tetrahydropyrimidin-4-yl)(hydroxy)methyl]-3-methyl-2a,3,4,5,5a,6,7,8-octahydro-2H-1,8,8b-triazaacenaphthylen-4-yl hydrogen sulfate
Other name(s): cyrI (gene name)
Systematic name: 7-deoxycylindrospermopsin,2-oxoglutarate:oxygen oxidoreductase (7-hydroxylating)
Comments: Requires Fe(II). The enzyme, found in some cyanobacterial species, catalyses the last step in the biosynthesis of the toxins cylindrospermopsin and 7-epi-cylindrospermopsin. The ratio of the two products differs among different strains.
References:
1.  Mazmouz, R., Chapuis-Hugon, F., Pichon V., Mejean, A., and Ploux, O. The last step of the biosynthesis of the cyanotoxins cylindrospermopsin and 7-epi-cylindrospermopsin is catalysed by CyrI, a 2-oxoglutarate-dependent iron oxygenase. ChemBioChem 12 (2011) 858–862.
2.  Mazmouz, R., Essadik, I., Hamdane, D., Mejean, A. and Ploux, O. Characterization of CyrI, the hydroxylase involved in the last step of cylindrospermopsin biosynthesis: Binding studies, site-directed mutagenesis and stereoselectivity. Arch. Biochem. Biophys. 647 (2018) 1–9. [PMID: 29653078]
[EC 1.14.11.70 created 2019]
 
 
EC 1.14.12.20      
Transferred entry: pheophorbide a oxygenase. Now classified as EC 1.14.15.17, pheophorbide a oxygenase.
[EC 1.14.12.20 created 2007, deleted 2016]
 
 
EC 1.14.13.41      
Transferred entry: tyrosine N-monooxygenase. Now EC 1.14.14.36, tyrosine N-monooxygenase
[EC 1.14.13.41 created 1992, modified 2001, modified 2005, deleted 2016]
 
 
EC 1.14.13.64     
Accepted name: 4-hydroxybenzoate 1-hydroxylase
Reaction: 4-hydroxybenzoate + NAD(P)H + 2 H+ + O2 = hydroquinone + NAD(P)+ + H2O + CO2
Other name(s): 4-hydroxybenzoate 1-monooxygenase
Systematic name: 4-hydroxybenzoate,NAD(P)H:oxygen oxidoreductase (1-hydroxylating, decarboxylating)
Comments: Requires FAD. The enzyme from Candida parapsilosis is specific for 4-hydroxybenzoate derivatives and prefers NADH to NADPH as electron donor.
References:
1.  van Berkel, W.J.H., Eppink, M.H.M., Middelhoven, W.J., Vervoort, J. and Rietjens, I.M.C.M. Catabolism of 4-hydroxybenzoate in Candida parapsilosis proceeds through initial oxidative decarboxylation by a FAD-dependent 4-hydroxybenzoate 1-hydroxylase. FEMS Microbiol. Lett. 121 (1994) 207–216. [PMID: 7926672]
[EC 1.14.13.64 created 1999]
 
 
EC 1.14.13.68      
Transferred entry: 4-hydroxyphenylacetaldehyde oxime monooxygenase. Now EC 1.14.14.37, 4-hydroxyphenylacetaldehyde oxime monooxygenase
[EC 1.14.13.68 created 2000, modified 2005, deleted 2016]
 
 
EC 1.14.13.78      
Transferred entry: ent-kaurene oxidase. Now EC 1.14.14.86, ent-kaurene monooxygenase
[EC 1.14.13.78 created 2002, deleted 2018]
 
 
EC 1.14.13.81     
Accepted name: magnesium-protoporphyrin IX monomethyl ester (oxidative) cyclase
Reaction: magnesium-protoporphyrin IX 13-monomethyl ester + 3 NADPH + 3 H+ + 3 O2 = 3,8-divinyl protochlorophyllide a + 3 NADP+ + 5 H2O (overall reaction)
(1a) magnesium-protoporphyrin IX 13-monomethyl ester + NADPH + H+ + O2 = 131-hydroxy-magnesium-protoporphyrin IX 13-monomethyl ester + NADP+ + H2O
(1b) 131-hydroxy-magnesium-protoporphyrin IX 13-monomethyl ester + NADPH + H+ + O2 = 131-oxo-magnesium-protoporphyrin IX 13-monomethyl ester + NADP+ + 2 H2O
(1c) 131-oxo-magnesium-protoporphyrin IX 13-monomethyl ester + NADPH + H+ + O2 = 3,8-divinyl protochlorophyllide a + NADP+ + 2 H2O
Other name(s): Mg-protoporphyrin IX monomethyl ester (oxidative) cyclase
Systematic name: magnesium-protoporphyrin-IX 13-monomethyl ester,NADPH:oxygen oxidoreductase (hydroxylating)
Comments: Requires Fe(II) for activity. The enzyme participates in the biosynthesis of chlorophyllide a in aerobic organisms. The same transformation is achieved in anaerobic organisms by EC 1.21.98.3, anaerobic magnesium-protoporphyrin IX monomethyl ester cyclase. Some facultative phototrophic bacteria, such as Rubrivivax gelatinosus, possess both enzymes.
References:
1.  Walker, C.J., Mansfield, K.E., Rezzano, I.N., Hanamoto, C.M., Smith, K.M. and Castelfranco, P.A. The magnesium-protoporphyrin IX (oxidative) cyclase system. Studies on the mechanism and specificity of the reaction sequence. Biochem. J. 255 (1988) 685–692. [PMID: 3202840]
2.  Bollivar, D.W. and Beale, S.I. The chlorophyll biosynthetic enzyme Mg-protoporphyrin IX monomethyl ester (oxidative) cyclase (characterization and partial purification from Chlamydomonas reinhardtii and Synechocystis sp. PCC 6803). Plant Physiol. 112 (1996) 105–114. [PMID: 12226378]
3.  Pinta, V., Picaud, M., Reiss-Husson, F. and Astier, C. Rubrivivax gelatinosus acsF (previously orf358) codes for a conserved, putative binuclear-iron-cluster-containing protein involved in aerobic oxidative cyclization of Mg-protoporphyrin IX monomethylester. J. Bacteriol. 184 (2002) 746–753. [PMID: 11790744]
4.  Tottey, S., Block, M.A., Allen, M., Westergren, T., Albrieux, C., Scheller, H.V., Merchant, S. and Jensen, P.E. Arabidopsis CHL27, located in both envelope and thylakoid membranes, is required for the synthesis of protochlorophyllide. Proc. Natl. Acad. Sci. USA 100 (2003) 16119–16124. [PMID: 14673103]
[EC 1.14.13.81 created 2003, modified 2017]
 
 
EC 1.14.13.88      
Transferred entry: flavanoid 3,5-hydroxylase. Now EC 1.14.14.81, flavanoid 3,5-hydroxylase
[EC 1.14.13.88 created 2004, deleted 2018]
 
 
EC 1.14.13.101     
Accepted name: senecionine N-oxygenase
Reaction: senecionine + NADPH + H+ + O2 = senecionine N-oxide + NADP+ + H2O
Other name(s): senecionine monooxygenase (N-oxide-forming); SNO
Systematic name: senecionine,NADPH:oxygen oxidoreductase (N-oxide-forming)
Comments: A flavoprotein. NADH cannot replace NADPH. While pyrrolizidine alkaloids of the senecionine and monocrotaline types are generally good substrates (e.g. senecionine, retrorsine and monocrotaline), the enzyme does not use ester alkaloids lacking an hydroxy group at C-7 (e.g. supinine and phalaenopsine), 1,2-dihydro-alkaloids (e.g. sarracine) or unesterified necine bases (e.g. senkirkine) as substrates [1]. Senecionine N-oxide is used by insects as a chemical defense: senecionine N-oxide is non-toxic, but it is bioactivated to a toxic form by the action of cytochrome P-450 oxidase when absorbed by insectivores.
References:
1.  Lindigkeit, R., Biller, A., Buch, M., Schiebel, H.M., Boppre, M. and Hartmann, T. The two facies of pyrrolizidine alkaloids: the role of the tertiary amine and its N-oxide in chemical defense of insects with acquired plant alkaloids. Eur. J. Biochem. 245 (1997) 626–636. [PMID: 9182998]
2.  Naumann, C., Hartmann, T. and Ober, D. Evolutionary recruitment of a flavin-dependent monooxygenase for the detoxification of host plant-acquired pyrrolizidine alkaloids in the alkaloid-defended arctiid moth Tyria jacobaeae. Proc. Natl. Acad. Sci. USA 99 (2002) 6085–6090. [PMID: 11972041]
[EC 1.14.13.101 created 2006]
 
 
EC 1.14.13.112      
Transferred entry: 3-epi-6-deoxocathasterone 23-monooxygenase. Now EC 1.14.14.147, 3-epi-6-deoxocathasterone 23-monooxygenase
[EC 1.14.13.112 created 2010, deleted 2018]
 
 
EC 1.14.13.119      
Transferred entry: 5-epiaristolochene 1,3-dihydroxylase. Now EC 1.14.14.149, 5-epiaristolochene 1,3-dihydroxylase
[EC 1.14.13.119 created 2011, deleted 2018]
 
 
EC 1.14.13.122     
Accepted name: chlorophyllide-a oxygenase
Reaction: chlorophyllide a + 2 O2 + 2 NADPH + 2 H+ = chlorophyllide b + 3 H2O + 2 NADP+ (overall reaction)
(1a) chlorophyllide a + O2 + NADPH + H+ = 71-hydroxychlorophyllide a + H2O + NADP+
(1b) 71-hydroxychlorophyllide a + O2 + NADPH + H+ = chlorophyllide b + 2 H2O + NADP+
Other name(s): chlorophyllide a oxygenase; chlorophyll-b synthase; CAO
Systematic name: chlorophyllide-a:oxygen 71-oxidoreductase
Comments: Chlorophyll b is required for the assembly of stable light-harvesting complexes (LHCs) in the chloroplast of green algae, cyanobacteria and plants [2,3]. Contains a mononuclear iron centre [3]. The enzyme catalyses two successive hydroxylations at the 7-methyl group of chlorophyllide a. The second step yields the aldehyde hydrate, which loses H2O spontaneously to form chlorophyllide b [2]. Chlorophyll a and protochlorophyllide a are not substrates [2].
References:
1.  Espineda, C.E., Linford, A.S., Devine, D. and Brusslan, J.A. The AtCAO gene, encoding chlorophyll a oxygenase, is required for chlorophyll b synthesis in Arabidopsis thaliana. Proc. Natl. Acad. Sci. USA 96 (1999) 10507–10511. [PMID: 10468639]
2.  Oster, U., Tanaka, R., Tanaka, A. and Rüdiger, W. Cloning and functional expression of the gene encoding the key enzyme for chlorophyll b biosynthesis (CAO) from Arabidopsis thaliana. Plant J. 21 (2000) 305–310. [PMID: 10758481]
3.  Eggink, L.L., LoBrutto, R., Brune, D.C., Brusslan, J., Yamasato, A., Tanaka, A. and Hoober, J.K. Synthesis of chlorophyll b: localization of chlorophyllide a oxygenase and discovery of a stable radical in the catalytic subunit. BMC Plant Biol. 4 (2004) 5. [PMID: 15086960]
4.  Porra, R.J., Schafer, W., Cmiel, E., Katheder, I. and Scheer, H. The derivation of the formyl-group oxygen of chlorophyll b in higher plants from molecular oxygen. Achievement of high enrichment of the 7-formyl-group oxygen from 18O2 in greening maize leaves. Eur. J. Biochem. 219 (1994) 671–679. [PMID: 8307032]
[EC 1.14.13.122 created 2006 as EC 1.13.12.14, transferred 2011 to EC 1.14.13.122, modified 2011]
 
 
EC 1.14.13.124      
Transferred entry: phenylalanine N-monooxygenase, now classified as EC 1.14.14.40, phenylalanine N-monooxygenase
[EC 1.14.13.124 created 2011, deleted 2017]
 
 
EC 1.14.13.125      
Transferred entry: tryptophan N-monooxygenase. Now EC 1.14.14.156, tryptophan N-monooxygenase
[EC 1.14.13.125 created 2011, deleted 2018]
 
 
EC 1.14.13.129      
Transferred entry: β-carotene 3-hydroxylase. Now EC 1.14.15.24, β-carotene 3-hydroxylase.
[EC 1.14.13.129 created 2011, deleted 2017]
 
 
EC 1.14.13.168     
Accepted name: indole-3-pyruvate monooxygenase
Reaction: (indol-3-yl)pyruvate + NADPH + H+ + O2 = (indol-3-yl)acetate + NADP+ + H2O + CO2
Glossary: (indol-3-yl)pyruvate = 3-(1H-indol-3-yl)-2-oxopropanoate, (indol-3-yl)acetate = 2-(1H-indol-3-yl)acetate = indole-3-acetate
Other name(s): YUC2 (gene name); spi1 (gene name)
Systematic name: indole-3-pyruvate,NADPH:oxygen oxidoreductase (1-hydroxylating, decarboxylating)
Comments: This plant enzyme, along with EC 2.6.1.99 L-tryptophan—pyruvate aminotransferase, is responsible for the biosynthesis of the plant hormone indole-3-acetate from L-tryptophan.
References:
1.  Mashiguchi, K., Tanaka, K., Sakai, T., Sugawara, S., Kawaide, H., Natsume, M., Hanada, A., Yaeno, T., Shirasu, K., Yao, H., McSteen, P., Zhao, Y., Hayashi, K., Kamiya, Y. and Kasahara, H. The main auxin biosynthesis pathway in Arabidopsis. Proc. Natl. Acad. Sci. USA 108 (2011) 18512–18517. [PMID: 22025724]
2.  Zhao, Y. Auxin biosynthesis: a simple two-step pathway converts tryptophan to indole-3-acetic acid in plants. Mol. Plant 5 (2012) 334–338. [PMID: 22155950]
[EC 1.14.13.168 created 2012]
 
 
EC 1.14.13.169      
Transferred entry: sphinganine C4-monooxygenase. Now EC 1.14.18.5, sphingolipid C4-monooxygenase
[EC 1.14.13.169 created 2012, deleted 2015]
 
 
EC 1.14.13.180     
Accepted name: aklavinone 12-hydroxylase
Reaction: aklavinone + NADPH + H+ + O2 = ε-rhodomycinone + NADP+ + H2O
Glossary: aklavinone = methyl (1R,2R,4S)-2-ethyl-2,4,5,7-tetrahydroxy-6,11-dioxo-1,2,3,4,6,11-hexahydrotetracene-1-carboxylate
ε-rhodomycinone = methyl (1R,2R,4S)-2-ethyl-2,4,5,7,12-pentahydroxy-6,11-dioxo-1,2,3,4,6,11-hexahydrotetracene-1-carboxylate
Other name(s): DnrF; RdmE; aklavinone 11-hydroxylase (incorrect)
Systematic name: aklavinone,NADPH:oxygen oxidoreductase (12-hydroxylating)
Comments: The enzymes from the Gram-positive bacteria Streptomyces peucetius and Streptomyces purpurascens participate in the biosynthesis of daunorubicin, doxorubicin and rhodomycins. The enzyme from Streptomyces purpurascens is an FAD monooxygenase.
References:
1.  Filippini, S., Solinas, M.M., Breme, U., Schluter, M.B., Gabellini, D., Biamonti, G., Colombo, A.L. and Garofano, L. Streptomyces peucetius daunorubicin biosynthesis gene, dnrF: sequence and heterologous expression. Microbiology 141 (1995) 1007–1016. [PMID: 7773378]
2.  Niemi, J., Wang, Y., Airas, K., Ylihonko, K., Hakala, J. and Mantsala, P. Characterization of aklavinone-11-hydroxylase from Streptomyces purpurascens. Biochim. Biophys. Acta 1430 (1999) 57–64. [PMID: 10082933]
[EC 1.14.13.180 created 2013]
 
 
EC 1.14.13.181     
Accepted name: 13-deoxydaunorubicin hydroxylase
Reaction: (1) 13-deoxydaunorubicin + NADPH + H+ + O2 = 13-dihydrodaunorubicin + NADP+ + H2O
(2) 13-dihydrodaunorubicin + NADPH + H+ + O2 = daunorubicin + NADP+ + 2 H2O
Glossary: 13-dihydrodaunorubicin = daunorubicinol = (1S,3S)-3,5,12-trihydroxy-3-(1-hydroxyethyl)-10-methoxy-6,11-dioxo-1,2,3,4,6,11-hexahydrotetracen-1-yl 3-amino-2,3,6-trideoxy-α-L-lyxo-hexopyranoside
13-deoxydaunorubicin = (1S,3S)-3-ethyl-3,5,12-trihydroxy-10-methoxy-6,11-dioxo-1,2,3,4,6,11-hexahydrotetracen-1-yl 3-amino-2,3,6-trideoxy-α-L-lyxo-hexopyranoside
daunorubicin = (1S,3S)-3-acetyl-3,5,12-trihydroxy-10-methoxy-6,11-dioxo-1,2,3,4,6,11-hexahydrotetracen-1-yl 3-amino-2,3,6-trideoxy-α-L-lyxo-hexopyranoside
Other name(s): DoxA
Systematic name: 13-deoxydaunorubicin,NADPH:oxygen oxidoreductase (13-hydroxylating)
Comments: The enzymes from the Gram-positive bacteria Streptomyces sp. C5 and Streptomyces peucetius show broad substrate specificity for structures based on an anthracycline aglycone, but have a strong preference for 4-methoxy anthracycline intermediates (13-deoxydaunorubicin and 13-dihydrodaunorubicin) over their 4-hydroxy analogues (13-deoxycarminomycin and 13-dihydrocarminomycin), as well as a preference for substrates hydroxylated at the C-13 rather than the C-14 position.
References:
1.  Walczak, R.J., Dickens, M.L., Priestley, N.D. and Strohl, W.R. Purification, properties, and characterization of recombinant Streptomyces sp. strain C5 DoxA, a cytochrome P-450 catalyzing multiple steps in doxorubicin biosynthesis. J. Bacteriol. 181 (1999) 298–304. [PMID: 9864343]
2.  Dickens, M.L., Priestley, N.D. and Strohl, W.R. In vivo and in vitro bioconversion of ε-rhodomycinone glycoside to doxorubicin: functions of DauP, DauK, and DoxA. J. Bacteriol. 179 (1997) 2641–2650. [PMID: 9098063]
[EC 1.14.13.181 created 2013]
 
 
EC 1.14.13.205      
Transferred entry: long-chain fatty acid ω-monooxygenase. Now EC 1.14.14.80, long-chain fatty acid ω-monooxygenase
[EC 1.14.13.205 created 2015, deleted 2018]
 
 
EC 1.14.13.237     
Accepted name: aliphatic glucosinolate S-oxygenase
Reaction: an ω-(methylsulfanyl)alkyl-glucosinolate + NADPH + H+ + O2 = an ω-(methylsulfinyl)alkyl-glucosinolate + NADP+ + H2O
Glossary: ω-(methylsulfanyl)alkyl-glucosinolate = an ω-(methylsulfanyl)-N-sulfo-alkylhydroximate S-glucoside
Other name(s): ω-(methylthio)alkylglucosinolate S-oxygenase; GS-OX1 (gene name); ω-(methylthio)alkyl-glucosinolate,NADPH:oxygen S-oxidoreductase
Systematic name: ω-(methylsulfanyl)alkyl-glucosinolate,NADPH:oxygen S-oxidoreductase
Comments: The enzyme is a member of the flavin-dependent monooxygenase (FMO) family (cf. EC 1.14.13.8). The plant Arabidopsis thaliana contains five isoforms. GS-OX1 through GS-OX4 are able to catalyse the S-oxygenation independent of chain length, while GS-OX5 is specific for 8-(methylsulfanyl)octyl glucosinolate.
References:
1.  Hansen, B.G., Kliebenstein, D.J. and Halkier, B.A. Identification of a flavin-monooxygenase as the S-oxygenating enzyme in aliphatic glucosinolate biosynthesis in Arabidopsis. Plant J. 50 (2007) 902–910. [PMID: 17461789]
2.  Li, J., Hansen, B.G., Ober, J.A., Kliebenstein, D.J. and Halkier, B.A. Subclade of flavin-monooxygenases involved in aliphatic glucosinolate biosynthesis. Plant Physiol. 148 (2008) 1721–1733. [PMID: 18799661]
[EC 1.14.13.237 created 2017]
 
 
EC 1.14.14.36     
Accepted name: tyrosine N-monooxygenase
Reaction: L-tyrosine + 2 O2 + 2 [reduced NADPH—hemoprotein reductase] = (E)-[4-hydroxyphenylacetaldehyde oxime] + 2 [oxidized NADPH—hemoprotein reductase] + CO2 + 3 H2O (overall reaction)
(1a) L-tyrosine + O2 + [reduced NADPH—hemoprotein reductase] = N-hydroxy-L-tyrosine + [oxidized NADPH—hemoprotein reductase] + H2O
(1b) N-hydroxy-L-tyrosine + O2 + [reduced NADPH—hemoprotein reductase] = N,N-dihydroxy-L-tyrosine + [oxidized NADPH—hemoprotein reductase] + H2O
(1c) N,N-dihydroxy-L-tyrosine = (E)-[4-hydroxyphenylacetaldehyde oxime] + CO2 + H2O
Other name(s): tyrosine N-hydroxylase; CYP79A1
Systematic name: L-tyrosine,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (N-hydroxylating)
Comments: A cytochrome P-450 (heme-thiolate) protein. The enzyme from Sorghum is involved in the biosynthesis of the cyanogenic glucoside dhurrin. In Sinapis alba (white mustard) the enzyme is involved in the biosynthesis of the glucosinolate sinalbin.
References:
1.  Halkier, B.A. and Møller, B.L. The biosynthesis of cyanogenic glucosides in higher plants. Identification of three hydroxylation steps in the biosynthesis of dhurrin in Sorghum bicolor (L.) Moench and the involvement of 1-ACI-nitro-2-(p-hydroxyphenyl)ethane as an intermediate. J. Biol. Chem. 265 (1990) 21114–21121. [PMID: 2250015]
2.  Sibbesen, O., Koch, B., Halkier, B.A. and Møller, B.L. Cytochrome P-450TYR is a multifunctional heme-thiolate enzyme catalyzing the conversion of L-tyrosine to p-hydroxyphenylacetaldehyde oxime in the biosynthesis of the cyanogenic glucoside dhurrin in Sorghum bicolor (L.) Moench. J. Biol. Chem. 270 (1995) 3506–3511. [PMID: 7876084]
3.  Bennett, R.N., Kiddle, G. and Wallsgrove, R.M. Involvement of cytochrome P450 in glucosinolate biosynthesis in white mustard (a biochemical anomaly). Plant Physiol. 114 (1997) 1283–1291. [PMID: 12223771]
4.  Kahn, R.A., Fahrendorf, T., Halkier, B.A. and Møller, B.L. Substrate specificity of the cytochrome P450 enzymes CYP79A1 and CYP71E1 involved in the biosynthesis of the cyanogenic glucoside dhurrin in Sorghum bicolor (L.) Moench. Arch. Biochem. Biophys. 363 (1999) 9–18. [PMID: 10049494]
5.  Bak, S., Olsen, C.E., Halkier, B.A. and Møller, B.L. Transgenic tobacco and Arabidopsis plants expressing the two multifunctional sorghum cytochrome P450 enzymes, CYP79A1 and CYP71E1, are cyanogenic and accumulate metabolites derived from intermediates in Dhurrin biosynthesis. Plant Physiol. 123 (2000) 1437–1448. [PMID: 10938360]
6.  Nielsen, J.S. and Møller, B.L. Cloning and expression of cytochrome P450 enzymes catalyzing the conversion of tyrosine to p-hydroxyphenylacetaldoxime in the biosynthesis of cyanogenic glucosides in Triglochin maritima. Plant Physiol. 122 (2000) 1311–1321. [PMID: 10759528]
7.  Busk, P.K. and Møller, B.L. Dhurrin synthesis in sorghum is regulated at the transcriptional level and induced by nitrogen fertilization in older plants. Plant Physiol. 129 (2002) 1222–1231. [PMID: 12114576]
8.  Kristensen, C., Morant, M., Olsen, C.E., Ekstrøm, C.T., Galbraith, D.W., Møller, B.L. and Bak, S. Metabolic engineering of dhurrin in transgenic Arabidopsis plants with marginal inadvertent effects on the metabolome and transcriptome. Proc. Natl. Acad. Sci. USA 102 (2005) 1779–1784. [PMID: 15665094]
9.  Clausen, M., Kannangara, R.M., Olsen, C.E., Blomstedt, C.K., Gleadow, R.M., Jørgensen, K., Bak, S., Motawie, M.S. and Møller, B.L. The bifurcation of the cyanogenic glucoside and glucosinolate biosynthetic pathways. Plant J. 84 (2015) 558–573. [PMID: 26361733]
[EC 1.14.14.36 created 1992 as EC 1.14.13.41, modified 2001, modified 2005, transferred 2016 to EC 1.14.14.36]
 
 
EC 1.14.14.37     
Accepted name: 4-hydroxyphenylacetaldehyde oxime monooxygenase
Reaction: (E)-4-hydroxyphenylacetaldehyde oxime + [reduced NADPH—hemoprotein reductase] + O2 = (S)-4-hydroxymandelonitrile + [oxidized NADPH—hemoprotein reductase] + 2 H2O (overall reaction)
(1a) (E)-4-hydroxyphenylacetaldehyde oxime = (Z)-4-hydroxyphenylacetaldehyde oxime
(1b) (Z)-4-hydroxyphenylacetaldehyde oxime = 4-hydroxyphenylacetonitrile + H2O
(1c) 4-hydroxyphenylacetonitrile + [reduced NADPH—hemoprotein reductase] + O2 = (S)-4-hydroxymandelonitrile + [oxidized NADPH—hemoprotein reductase] + H2O
Glossary: (S)-4-hydroxymandelonitrile = (2S)-hydroxy(4-hydroxyphenyl)acetonitrile
Other name(s): 4-hydroxybenzeneacetaldehyde oxime monooxygenase; cytochrome P450II-dependent monooxygenase; NADPH-cytochrome P450 reductase (CYP71E1); CYP71E1; 4-hydroxyphenylacetaldehyde oxime,NADPH:oxygen oxidoreductase
Systematic name: (E)-4-hydroxyphenylacetaldehyde oxime,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase
Comments: This cytochrome P-450 (heme thiolate) enzyme is involved in the biosynthesis of the cyanogenic glucoside dhurrin in sorghum. It catalyses three different activities - isomerization of the (E) isomer to the (Z) isomer, dehydration, and C-hydroxylation.
References:
1.  MacFarlane, I.J., Lees, E.M. and Conn, E.E. The in vitro biosynthesis of dhurrin, the cyanogenic glycoside of Sorghum bicolor. J. Biol. Chem. 250 (1975) 4708–4713. [PMID: 237909]
2.  Shimada, M. and Conn, E.E. The enzymatic conversion of p-hydroxyphenylacetaldoxime to p-hydroxymandelonitrile. Arch. Biochem. Biophys. 180 (1977) 199–207. [PMID: 193443]
3.  Busk, P.K. and Møller, B.L. Dhurrin synthesis in sorghum is regulated at the transcriptional level and induced by nitrogen fertilization in older plants. Plant Physiol. 129 (2002) 1222–1231. [PMID: 12114576]
4.  Kristensen, C., Morant, M., Olsen, C.E., Ekstrøm, C.T., Galbraith, D.W., Møller, B.L. and Bak, S. Metabolic engineering of dhurrin in transgenic Arabidopsis plants with marginal inadvertent effects on the metabolome and transcriptome. Proc. Natl. Acad. Sci. USA 102 (2005) 1779–1784. [PMID: 15665094]
5.  Clausen, M., Kannangara, R.M., Olsen, C.E., Blomstedt, C.K., Gleadow, R.M., Jørgensen, K., Bak, S., Motawie, M.S. and Møller, B.L. The bifurcation of the cyanogenic glucoside and glucosinolate biosynthetic pathways. Plant J. 84 (2015) 558–573. [PMID: 26361733]
[EC 1.14.14.37 created 2000 as EC 1.14.13.68, modified 2005, transferred 2016 to EC 1.14.14.37]
 
 
EC 1.14.14.40     
Accepted name: phenylalanine N-monooxygenase
Reaction: L-phenylalanine + 2 [reduced NADPH—hemoprotein reductase] + 2 O2 = (E)-phenylacetaldoxime + 2 [oxidized NADPH—hemoprotein reductase] + CO2 + 3 H2O (overall reaction)
(1a) L-phenylalanine + [reduced NADPH—hemoprotein reductase] + O2 = N-hydroxy-L-phenylalanine + [oxidized NADPH—hemoprotein reductase] + H2O
(1b) N-hydroxy-L-phenylalanine + [reduced NADPH—hemoprotein reductase] + O2 = N,N-dihydroxy-L-phenylalanine + [oxidized NADPH—hemoprotein reductase] + H2O
(1c) N,N-dihydroxy-L-phenylalanine = (E)-phenylacetaldoxime + CO2 + H2O
Other name(s): phenylalanine N-hydroxylase; CYP79A2 (gene name); CYP79D16 (gene name)
Systematic name: L-phenylalanine,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (N-hydroxylating)
Comments: This cytochrome P-450 (heme-thiolate) enzyme, found in plants, catalyses two successive N-hydroxylations of L-phenylalanine, a committed step in the biosynthesis of benzylglucosinolate and the cyanogenic glucosides (R)-prunasin and (R)-amygdalin. The product of the two hydroxylations, N,N-dihydroxy-L-phenylalanine, is labile and undergoes dehydration followed by decarboxylation, producing an oxime. It is still not known whether the decarboxylation is spontaneous or catalysed by the enzyme.
References:
1.  Wittstock, U. and Halkier, B.A. Cytochrome P450 CYP79A2 from Arabidopsis thaliana L. Catalyzes the conversion of L-phenylalanine to phenylacetaldoxime in the biosynthesis of benzylglucosinolate. J. Biol. Chem. 275 (2000) 14659–14666. [PMID: 10799553]
2.  Yamaguchi, T., Yamamoto, K. and Asano, Y. Identification and characterization of CYP79D16 and CYP71AN24 catalyzing the first and second steps in L-phenylalanine-derived cyanogenic glycoside biosynthesis in the Japanese apricot, Prunus mume Sieb. et Zucc. Plant Mol. Biol. 86 (2014) 215–223. [PMID: 25015725]
[EC 1.14.14.40 created 2011 as EC 1.14.13.124, transferred 2017 to EC 1.14.14.40]
 
 
EC 1.14.14.42     
Accepted name: homomethionine N-monooxygenase
Reaction: an L-polyhomomethionine + 2 [reduced NADPH—hemoprotein reductase] + 2 O2 = an (E)-ω-(methylsulfanyl)alkanal oxime + 2 [oxidized NADPH—hemoprotein reductase] + CO2 + 3 H2O (overall reaction)
(1a) an L-polyhomomethionine + [reduced NADPH—hemoprotein reductase] + O2 = an L-N-hydroxypolyhomomethionine + [oxidized NADPH—hemoprotein reductase] + H2O
(1b) an L-N-hydroxypolyhomomethionine + [reduced NADPH—hemoprotein reductase] + O2 = an L-N,N-dihydroxypolyhomomethionine + [oxidized NADPH—hemoprotein reductase] + H2O
(1c) an L-N,N-dihydroxypolyhomomethionine = an (E)-ω-(methylsulfanyl)alkanal oxime + CO2 + H2O
Glossary: homomethionine = (2S)-2-amino-5-(methylsulfanyl)pentanoate
an L-polyhomomethionine = analogs of L-methionine that contain additional methylene groups in the side chain prior to the sulfur atom.
Other name(s): CYP79F1 (gene name); CYP79F2 (gene name)
Systematic name: L-polyhomomethionine,[NADPH—hemoprotein reductase]:oxygen oxidoreductase
Comments: This plant cytochrome P-450 (heme thiolate) enzyme is involved in methionine-derived aliphatic glucosinolates biosynthesis. It catalyses two successive N-hydroxylations, which are followed by dehydration and decarboxylation. CYP79F1 from Arabidopsis thaliana can metabolize mono-, di-, tri-, tetra-, penta-, and hexahomomethionine to their corresponding aldoximes, while CYP79F2 from the same plant can only metabolize penta- and hexahomomethionine.
References:
1.  Hansen, C.H., Wittstock, U., Olsen, C.E., Hick, A.J., Pickett, J.A. and Halkier, B.A. Cytochrome p450 CYP79F1 from arabidopsis catalyzes the conversion of dihomomethionine and trihomomethionine to the corresponding aldoximes in the biosynthesis of aliphatic glucosinolates. J. Biol. Chem. 276 (2001) 11078–11085. [PMID: 11133994]
2.  Chen, S., Glawischnig, E., Jørgensen, K., Naur, P., Jorgensen, B., Olsen, C.E., Hansen, C.H., Rasmussen, H., Pickett, J.A. and Halkier, B.A. CYP79F1 and CYP79F2 have distinct functions in the biosynthesis of aliphatic glucosinolates in Arabidopsis. Plant J. 33 (2003) 923–937. [PMID: 12609033]
[EC 1.14.14.42 created 2017]
 
 
EC 1.14.14.43     
Accepted name: (methylsulfanyl)alkanaldoxime N-monooxygenase
Reaction: an (E)-ω-(methylsulfanyl)alkanal oxime + [reduced NADPH—hemoprotein reductase] + glutathione + O2 = an S-[(1E)-1-(hydroxyimino)-ω-(methylsulfanyl)alkyl]-L-glutathione + [oxidized NADPH—hemoprotein reductase] + 2 H2O (overall reaction)
(1a) an (E)-ω-(methylsulfanyl)alkanal oxime + [reduced NADPH—hemoprotein reductase] + O2 = a 1-(methylsulfanyl)-4-aci-nitroalkane + [oxidized NADPH—hemoprotein reductase] + H2O
(1b) a 1-(methylsulfanyl)-4-aci-nitroalkane + glutathione = an S-[(1E)-1-(hydroxyimino)-ω-(methylsulfanyl)alkyl]-L-glutathione + H2O
Glossary: a 1-(methylsulfanyl)-4-aci-nitroalkane = a hydroxyoxo-λ5-azanylidene-ω-(methylsulfanyl)alkane
Other name(s): CYP83A1 (gene name); (methylthio)alkanaldoxime N-monooxygenase; (E)-ω-(methylthio)alkananaldoxime,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (N-hydroxylating)
Systematic name: (E)-ω-(methylsulfanyl)alkananal oxime,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (N-hydroxylating)
Comments: This cytochrome P-450 (heme thiolate) enzyme is involved in the biosynthesis of glucosinolates in plants. The enzyme catalyses an N-hydroxylation of the E isomer of ω-(methylsulfanyl)alkanal oximes, forming an aci-nitro intermediate that reacts non-enzymically with glutathione to produce an N-alkyl-thiohydroximate adduct, the committed precursor of glucosinolates. In the absence of a thiol compound, the enzyme is suicidal, probably due to interaction of the reactive aci-nitro intermediate with active site residues.
References:
1.  Bak, S., Tax, F.E., Feldmann, K.A., Galbraith, D.W. and Feyereisen, R. CYP83B1, a cytochrome P450 at the metabolic branch point in auxin and indole glucosinolate biosynthesis in Arabidopsis. Plant Cell 13 (2001) 101–111. [PMID: 11158532]
2.  Naur, P., Petersen, B.L., Mikkelsen, M.D., Bak, S., Rasmussen, H., Olsen, C.E. and Halkier, B.A. CYP83A1 and CYP83B1, two nonredundant cytochrome P450 enzymes metabolizing oximes in the biosynthesis of glucosinolates in Arabidopsis. Plant Physiol. 133 (2003) 63–72. [PMID: 12970475]
3.  Clausen, M., Kannangara, R.M., Olsen, C.E., Blomstedt, C.K., Gleadow, R.M., Jørgensen, K., Bak, S., Motawie, M.S. and Møller, B.L. The bifurcation of the cyanogenic glucoside and glucosinolate biosynthetic pathways. Plant J. 84 (2015) 558–573. [PMID: 26361733]
[EC 1.14.14.43 created 2017]
 
 
EC 1.14.14.45     
Accepted name: aromatic aldoxime N-monooxygenase
Reaction: (1) (E)-indol-3-ylacetaldehyde oxime + [reduced NADPH—hemoprotein reductase] + glutathione + O2 = S-[(E)-N-hydroxy(indol-3-yl)acetimidoyl]-L-glutathione + [oxidized NADPH—hemoprotein reductase] + 2 H2O (overall reaction)
(1a) (E)-indol-3-ylacetaldehyde oxime + [reduced NADPH—hemoprotein reductase] + O2 = 1-(1H-indol-3-yl)-2-aci-nitroethane + [oxidized NADPH—hemoprotein reductase] + H2O
(1b) 1-(1H-indol-3-yl)-2-aci-nitroethane + glutathione = S-[(E)-N-hydroxy(indol-3-yl)acetimidoyl]-L-glutathione + H2O (spontaneous)
(2) (E)-phenylacetaldehyde oxime + [reduced NADPH—hemoprotein reductase] + glutathione + O2 = S-[(Z)-N-hydroxy(phenyl)acetimidoyl]-L-glutathione + [oxidized NADPH—hemoprotein reductase] + 2 H2O (overall reaction)
(2a) (E)-phenylacetaldehyde oxime + [reduced NADPH—hemoprotein reductase] + O2 = 1-aci-nitro-2-phenylethane + [oxidized NADPH—hemoprotein reductase] + H2O
(2b) 1-aci-nitro-2-phenylethane + glutathione = S-[(Z)-N-hydroxy(phenyl)acetimidoyl]-L-glutathione + H2O (spontaneous)
Other name(s): CYP83B1 (gene name)
Systematic name: (E)-indol-3-ylacetaldoxime,[reduced NADPH—hemoprotein reductase],glutathione:oxygen oxidoreductase (oxime-hydroxylating)
Comments: This cytochrome P-450 (heme thiolate) enzyme is involved in the biosynthesis of glucosinolates in plants. The enzyme catalyses the N-hydroxylation of aromatic aldoximes derived from L-tryptophan, L-phenylalanine, and L-tyrosine, forming an aci-nitro intermediate that reacts non-enzymically with glutathione to produce an N-alkyl-thiohydroximate adduct, the committed precursor of glucosinolates. In the absence of glutathione, the enzyme is suicidal, probably due to interaction of the reactive aci-nitro compound with catalytic residues in the active site.
References:
1.  Bak, S., Tax, F.E., Feldmann, K.A., Galbraith, D.W. and Feyereisen, R. CYP83B1, a cytochrome P450 at the metabolic branch point in auxin and indole glucosinolate biosynthesis in Arabidopsis. Plant Cell 13 (2001) 101–111. [PMID: 11158532]
2.  Naur, P., Petersen, B.L., Mikkelsen, M.D., Bak, S., Rasmussen, H., Olsen, C.E. and Halkier, B.A. CYP83A1 and CYP83B1, two nonredundant cytochrome P450 enzymes metabolizing oximes in the biosynthesis of glucosinolates in Arabidopsis. Plant Physiol. 133 (2003) 63–72. [PMID: 12970475]
3.  Geu-Flores, F., Møldrup, M.E., Böttcher, C., Olsen, C.E., Scheel, D. and Halkier, B.A. Cytosolic γ-glutamyl peptidases process glutathione conjugates in the biosynthesis of glucosinolates and camalexin in Arabidopsis. Plant Cell 23 (2011) 2456–2469. [PMID: 21712415]
[EC 1.14.14.45 created 2017]
 
 
EC 1.14.14.48     
Accepted name: jasmonoyl-L-amino acid 12-hydroxylase
Reaction: a jasmonoyl-L-amino acid + [reduced NADPH—hemoprotein reductase] + O2 = a 12-hydroxyjasmonoyl-L-amino acid + [oxidized NADPH—hemoprotein reductase] + H2O
Glossary: jasmonic acid = {(1R,2R)-3-oxo-2-[(2Z)pent-2-en-1-yl]cyclopentyl}acetic acid
(+)-7-epi-jasmonic acid = {(1R,2S)-3-oxo-2-[(2Z)pent-2-en-1-yl]cyclopentyl}acetic acid
Other name(s): CYP94B1 (gene name); CYP94B3 (gene name)
Systematic name: jasmonoyl-L-amino acid,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (12-hydroxylating)
Comments: A cytochrome P450 (heme thiolate) enzyme found in plants. The enzyme acts on jasmonoyl-L-amino acid conjugates, catalysing the hydroxylation of the C-12 position of jasmonic acid. While the best studied substrate is (+)-7-epi-jasmonoyl-L-isoleucine, the enzyme was shown to be active with jasmonoyl-L-valine and jasmonoyl-L-phenylalanine, and is likely to be active with other jasmonoyl-amino acid conjugates.
References:
1.  Koo, A.J., Cooke, T.F. and Howe, G.A. Cytochrome P450 CYP94B3 mediates catabolism and inactivation of the plant hormone jasmonoyl-L-isoleucine. Proc. Natl. Acad. Sci. USA 108 (2011) 9298–9303. [PMID: 21576464]
2.  Kitaoka, N., Matsubara, T., Sato, M., Takahashi, K., Wakuta, S., Kawaide, H., Matsui, H., Nabeta, K. and Matsuura, H. Arabidopsis CYP94B3 encodes jasmonyl-L-isoleucine 12-hydroxylase, a key enzyme in the oxidative catabolism of jasmonate. Plant Cell Physiol. 52 (2011) 1757–1765. [PMID: 21849397]
3.  Heitz, T., Widemann, E., Lugan, R., Miesch, L., Ullmann, P., Desaubry, L., Holder, E., Grausem, B., Kandel, S., Miesch, M., Werck-Reichhart, D. and Pinot, F. Cytochromes P450 CYP94C1 and CYP94B3 catalyze two successive oxidation steps of plant hormone jasmonoyl-isoleucine for catabolic turnover. J. Biol. Chem. 287 (2012) 6296–6306. [PMID: 22215670]
4.  Kitaoka, N., Kawaide, H., Amano, N., Matsubara, T., Nabeta, K., Takahashi, K. and Matsuura, H. CYP94B3 activity against jasmonic acid amino acid conjugates and the elucidation of 12-O-β-glucopyranosyl-jasmonoyl-L-isoleucine as an additional metabolite. Phytochemistry 99 (2014) 6–13. [PMID: 24467969]
5.  Koo, A.J., Thireault, C., Zemelis, S., Poudel, A.N., Zhang, T., Kitaoka, N., Brandizzi, F., Matsuura, H. and Howe, G.A. Endoplasmic reticulum-associated inactivation of the hormone jasmonoyl-L-isoleucine by multiple members of the cytochrome P450 94 family in Arabidopsis. J. Biol. Chem. 289 (2014) 29728–29738. [PMID: 25210037]
6.  Widemann, E., Grausem, B., Renault, H., Pineau, E., Heinrich, C., Lugan, R., Ullmann, P., Miesch, L., Aubert, Y., Miesch, M., Heitz, T. and Pinot, F. Sequential oxidation of jasmonoyl-phenylalanine and jasmonoyl-isoleucine by multiple cytochrome P450 of the CYP94 family through newly identified aldehyde intermediates. Phytochemistry 117 (2015) 388–399. [PMID: 26164240]
[EC 1.14.14.48 created 2017]
 
 
EC 1.14.14.58     
Accepted name: trimethyltridecatetraene synthase
Reaction: (6E,10E)-geranyllinalool + [reduced NADPH—hemoprotein reductase] + O2 = (3E,7E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene + [oxidized NADPH—hemoprotein reductase] + but-3-en-2-one + 2 H2O
Glossary: (6E,10E)-geranyllinalool = (6E,10E)-3,7,11,15-tetramethylhexadeca-1,6,10,14-tetraen-3-ol
Other name(s): CYP82G1; CYP92C5; CYP92C6; DMNT/TMTT homoterpene synthase
Systematic name: (6E,10E)-geranyllinalool,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase
Comments: A cytochrome P-450 (heme-thiolate) protein isolated from the plants Arabidopsis thaliana (thale cress) and Zea mays (maize). It forms this C16 homoterpene in response to herbivore attack. In vitro some variants of the enzyme also convert (3S,6E)-nerolidol to (3E)-4,8-dimethylnona-1,3,7-triene (see EC 1.14.14.59, dimethylnonatriene synthase).
References:
1.  Lee, S., Badieyan, S., Bevan, D.R., Herde, M., Gatz, C. and Tholl, D. Herbivore-induced and floral homoterpene volatiles are biosynthesized by a single P450 enzyme (CYP82G1) in Arabidopsis. Proc. Natl. Acad. Sci. USA 107 (2010) 21205–21210. [PMID: 21088219]
2.  Richter, A., Schaff, C., Zhang, Z., Lipka, A.E., Tian, F., Kollner, T.G., Schnee, C., Preiss, S., Irmisch, S., Jander, G., Boland, W., Gershenzon, J., Buckler, E.S. and Degenhardt, J. Characterization of biosynthetic pathways for the production of the volatile homoterpenes DMNT and TMTT in Zea mays. Plant Cell 28 (2016) 2651–2665. [PMID: 27662898]
[EC 1.14.14.58 created 2018]
 
 
EC 1.14.14.59     
Accepted name: dimethylnonatriene synthase
Reaction: (3S,6E)-nerolidol + [reduced NADPH—hemoprotein reductase] + O2 = (3E)-4,8-dimethylnona-1,3,7-triene + [oxidized NADPH—hemoprotein reductase] + but-3-en-2-one + 2 H2O
Other name(s): CYP82G1; CYP92C5; DMNT/TMTT homoterpene synthase
Systematic name: (3S,6E)-nerolidol,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase
Comments: A cytochrome P-450 (heme-thiolate) protein isolated from the plants Arabidopsis thaliana (thale cress) and Zea mays (maize). It forms this C11 homoterpene in response to herbivore attack. In vitro the enzyme also converts (6E,10E)-geranyllinalool to (3E,7E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene (see EC 1.14.14.58, trimethyltridecatetraene synthase).
References:
1.  Lee, S., Badieyan, S., Bevan, D.R., Herde, M., Gatz, C. and Tholl, D. Herbivore-induced and floral homoterpene volatiles are biosynthesized by a single P450 enzyme (CYP82G1) in Arabidopsis. Proc. Natl. Acad. Sci. USA 107 (2010) 21205–21210. [PMID: 21088219]
2.  Richter, A., Schaff, C., Zhang, Z., Lipka, A.E., Tian, F., Kollner, T.G., Schnee, C., Preiss, S., Irmisch, S., Jander, G., Boland, W., Gershenzon, J., Buckler, E.S. and Degenhardt, J. Characterization of biosynthetic pathways for the production of the volatile homoterpenes DMNT and TMTT in Zea mays. Plant Cell 28 (2016) 2651–2665. [PMID: 27662898]
[EC 1.14.14.59 created 2018]
 
 
EC 1.14.14.80     
Accepted name: long-chain fatty acid ω-monooxygenase
Reaction: a long-chain fatty acid + [reduced NADPH—hemoprotein reductase] + O2 = an ω-hydroxy-long-chain fatty acid + [oxidized NADPH—hemoprotein reductase] + H2O
Other name(s): CYP704B1 (gene name); CYP52M1 (gene name); CYP4A (gene name); CYP86A (gene name)
Systematic name: long-chain fatty acid,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (ω-hydroxylating)
Comments: A cytochrome P-450 (heme thiolate) enzyme. The plant enzyme CYP704B1, which is involved in the synthesis of sporopollenin, a complex polymer found at the outer layer of spores and pollen, acts on palmitate (18:0), stearate (18:0) and oleate (18:1). The plant enzyme CYP86A1 also acts on laurate (12:0). The enzyme from the yeast Starmerella bombicola (CYP52M1) acts on C16 to C20 saturated and unsaturated fatty acids and can also hydroxylate the (ω-1) position. The mammalian enzyme CYP4A acts on laurate (12:0), myristate (14:0), palmitate (16:0), oleate (18:1), and arachidonate (20:4).
References:
1.  Benveniste, I., Tijet, N., Adas, F., Philipps, G., Salaun, J.P. and Durst, F. CYP86A1 from Arabidopsis thaliana encodes a cytochrome P450-dependent fatty acid ω-hydroxylase. Biochem. Biophys. Res. Commun. 243 (1998) 688–693. [PMID: 9500987]
2.  Hoch, U., Zhang, Z., Kroetz, D.L. and Ortiz de Montellano, P.R. Structural determination of the substrate specificities and regioselectivities of the rat and human fatty acid ω-hydroxylases. Arch. Biochem. Biophys. 373 (2000) 63–71. [PMID: 10620324]
3.  Dobritsa, A.A., Shrestha, J., Morant, M., Pinot, F., Matsuno, M., Swanson, R., Møller, B.L. and Preuss, D. CYP704B1 is a long-chain fatty acid ω-hydroxylase essential for sporopollenin synthesis in pollen of Arabidopsis. Plant Physiol. 151 (2009) 574–589. [PMID: 19700560]
4.  Huang, F.C., Peter, A. and Schwab, W. Expression and characterization of CYP52 genes involved in the biosynthesis of sophorolipid and alkane metabolism from Starmerella bombicola. Appl. Environ. Microbiol. 80 (2014) 766–776. [PMID: 24242247]
[EC 1.14.14.80 created 2015 as EC 1.14.13.205, transferred 2018 to EC 1.14.14.80]
 
 
EC 1.14.14.81     
Accepted name: flavanoid 3′,5′-hydroxylase
Reaction: a flavanone + 2 [reduced NADPH—hemoprotein reductase] + 2 O2 = a 3′,5′-dihydroxyflavanone + 2 [oxidized NADPH—hemoprotein reductase] + 2 H2O (overall reaction)
(1a) a flavanone + [reduced NADPH—hemoprotein reductase] + O2 = a 3′-hydroxyflavanone + [oxidized NADPH—hemoprotein reductase] + H2O
(1b) a 3′-hydroxyflavanone + [reduced NADPH—hemoprotein reductase] + O2 = a 3′,5′-dihydroxyflavanone + [oxidized NADPH—hemoprotein reductase] + H2O
Other name(s): flavonoid 3′,5′-hydroxylase
Systematic name: flavanone,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (3′,5′-dihydroxylating)
Comments: A cytochrome P-450 (heme-thiolate) protein found in plants. The 3′,5′-dihydroxyflavanone is formed via the 3′-hydroxyflavanone. In Petunia hybrida the enzyme acts on naringenin, eriodictyol, dihydroquercetin (taxifolin) and dihydrokaempferol (aromadendrin). The enzyme catalyses the hydroxylation of 5,7,4′-trihydroxyflavanone (naringenin) at either the 3′ position to form eriodictyol or at both the 3′ and 5′ positions to form 5,7,3′,4′,5′-pentahydroxyflavanone (dihydrotricetin). The enzyme also catalyses the hydroxylation of 3,5,7,3′,4′-pentahydroxyflavanone (taxifolin) at the 5′ position, forming ampelopsin.
References:
1.  Menting, J., Scopes, R.K. and Stevenson, T.W. Characterization of flavonoid 3′,5′-hydroxylase in microsomal membrane fraction of Petunia hybrida flowers. Plant Physiol. 106 (1994) 633–642. [PMID: 12232356]
2.  Shimada, Y., Nakano-Shimada, R., Ohbayashi, M., Okinaka, Y., Kiyokawa, S. and Kikuchi, Y. Expression of chimeric P450 genes encoding flavonoid-3′, 5′-hydroxylase in transgenic tobacco and petunia plants1. FEBS Lett. 461 (1999) 241–245. [PMID: 10567704]
3.  de Vetten, N., ter Horst, J., van Schaik, H.P., de Boer, A., Mol, J. and Koes, R. A cytochrome b5 is required for full activity of flavonoid 3′, 5′-hydroxylase, a cytochrome P450 involved in the formation of blue flower colors. Proc. Natl. Acad. Sci. USA 96 (1999) 778–783. [PMID: 9892710]
[EC 1.14.14.81 created 2004 as EC 1.14.13.88, transferred 2018 to EC 1.14.14.81]
 
 
EC 1.14.14.82     
Accepted name: flavonoid 3′-monooxygenase
Reaction: a flavonoid + [reduced NADPH—hemoprotein reductase] + O2 = a 3′-hydroxyflavonoid + [oxidized NADPH—hemoprotein reductase] + H2O
Other name(s): CYP75B1 (gene name); flavonoid 3′-hydroxylase; flavonoid 3-hydroxylase (incorrect); NADPH:flavonoid-3′-hydroxylase (incorrect); flavonoid 3-monooxygenase (incorrect)
Systematic name: flavonoid,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (3′-hydroxylating)
Comments: A cytochrome P-450 (heme-thiolate) protein found in plants. Acts on a number of flavonoids, including the flavanone naringenin and the flavone apigenin. Does not act on 4-coumarate or 4-coumaroyl-CoA.
References:
1.  Forkmann, G., Heller, W. and Grisebach, H. Anthocyanin biosynthesis in flowers of Matthiola incana flavanone 3- and flavonoid 3′-hydroxylases. Z. Naturforsch. C: Biosci. 35 (1980) 691–695.
2.  Brugliera, F., Barri-Rewell, G., Holton, T.A. and Mason, J.G. Isolation and characterization of a flavonoid 3′-hydroxylase cDNA clone corresponding to the Ht1 locus of Petunia hybrida. Plant J. 19 (1999) 441–451. [PMID: 10504566]
3.  Schoenbohm, C., Martens, S., Eder, C., Forkmann, G. and Weisshaar, B. Identification of the Arabidopsis thaliana flavonoid 3′-hydroxylase gene and functional expression of the encoded P450 enzyme. Biol. Chem. 381 (2000) 749–753. [PMID: 11030432]
[EC 1.14.14.82 created 1983 as EC 1.14.13.21, transferred 2018 to EC 1.14.14.82]
 
 
EC 1.14.14.86     
Accepted name: ent-kaurene monooxygenase
Reaction: ent-kaur-16-ene + 3 [reduced NADPH—hemoprotein reductase] + 3 O2 = ent-kaur-16-en-19-oate + 3 [oxidized NADPH—hemoprotein reductase] + 4 H2O (overall reaction)
(1a) ent-kaur-16-ene + [reduced NADPH—hemoprotein reductase] + O2 = ent-kaur-16-en-19-ol + [oxidized NADPH—hemoprotein reductase] + H2O
(1b) ent-kaur-16-en-19-ol + [reduced NADPH—hemoprotein reductase] + O2 = ent-kaur-16-en-19-al + [oxidized NADPH—hemoprotein reductase] + 2 H2O
(1c) ent-kaur-16-en-19-al + [reduced NADPH—hemoprotein reductase] + O2 = ent-kaur-16-en-19-oate + [oxidized NADPH—hemoprotein reductase] + H2O
Other name(s): ent-kaurene oxidase (misleading)
Systematic name: ent-kaur-16-ene,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (hydroxylating)
Comments: A cytochrome P-450 (heme thiolate) protein found in plants. Catalyses three successive oxidations of the 4-methyl group of ent-kaurene giving kaurenoic acid.
References:
1.  Ashman, P.J., Mackenzie, A. and Bramley, P.M. Characterization of ent-kaurene oxidase activity from Gibberella fujikuroi. Biochim. Biophys. Acta 1036 (1990) 151–157. [PMID: 2223832]
2.  Archer, C., Ashman, P.J., Hedden, P., Bowyer, J.R. and Bramley, P.M. Purification of ent-kaurene oxidase from Gibberella fujikuroi and Cucurbita maxima. Biochem. Soc. Trans. 20 (1992) 218. [PMID: 1397591]
3.  Helliwell, C.A., Poole, A., Peacock, W.J. and Dennis, E.S. Arabidopsis ent-kaurene oxidase catalyzes three steps of gibberellin biosynthesis. Plant Physiol. 119 (1999) 507–510. [PMID: 9952446]
[EC 1.14.14.86 created 2002 as EC 1.14.13.78, transferred 2018 to EC 1.14.14.86]
 
 
EC 1.14.14.96     
Accepted name: 5-O-(4-coumaroyl)-D-quinate 3′-monooxygenase
Reaction: trans-5-O-(4-coumaroyl)-D-quinate + [reduced NADPH—hemoprotein reductase] + O2 = trans-5-O-caffeoyl-D-quinate + [oxidized NADPH—hemoprotein reductase] + H2O
Other name(s): 5-O-(4-coumaroyl)-D-quinate/shikimate 3′-hydroxylase; coumaroylquinate(coumaroylshikimate) 3′-monooxygenase; CYP98A3 (gene name)
Systematic name: trans-5-O-(4-coumaroyl)-D-quinate,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (3′-hydroxylating)
Comments: A cytochrome P-450 (heme-thiolate) protein, found in plants. It also acts on trans-5-O-(4-coumaroyl)shikimate.
References:
1.  Kühnl, T., Koch, U., Heller, W. and Wellman, E. Chlorogenic acid biosynthesis: characterization of a light-induced microsomal 5-O-(4-coumaroyl)-D-quinate/shikimate 3′-hydroxylase from carrot (Daucus carota L.) cell suspension cultures. Arch. Biochem. Biophys. 258 (1987) 226–232. [PMID: 2821918]
2.  Schoch, G., Goepfert, S., Morant, M., Hehn, A., Meyer, D., Ullmann, P. and Werck-Reichhart, D. CYP98A3 from Arabidopsis thaliana is a 3′-hydroxylase of phenolic esters, a missing link in the phenylpropanoid pathway. J. Biol. Chem. 276 (2001) 36566–36574. [PMID: 11429408]
3.  Franke, R., Humphreys, J.M., Hemm, M.R., Denault, J.W., Ruegger, M.O., Cusumano, J.C. and Chapple, C. The Arabidopsis REF8 gene encodes the 3-hydroxylase of phenylpropanoid metabolism. Plant J. 30 (2002) 33–45. [PMID: 11967091]
4.  Matsuno, M., Compagnon, V., Schoch, G.A., Schmitt, M., Debayle, D., Bassard, J.E., Pollet, B., Hehn, A., Heintz, D., Ullmann, P., Lapierre, C., Bernier, F., Ehlting, J. and Werck-Reichhart, D. Evolution of a novel phenolic pathway for pollen development. Science 325 (2009) 1688–1692. [PMID: 19779199]
[EC 1.14.14.96 created 1990 as EC 1.14.13.36, transferred 2018 to EC 1.14.14.96]
 
 
EC 1.14.14.137     
Accepted name: (+)-abscisic acid 8′-hydroxylase
Reaction: (+)-abscisate + [reduced NADPH—hemoprotein reductase] + O2 = 8′-hydroxyabscisate + [oxidized NADPH—hemoprotein reductase] + H2O
Other name(s): (+)-ABA 8′-hydroxylase; ABA 8′-hydroxylase; CYP707A1 (gene name)
Systematic name: abscisate,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (8′-hydroxylating)
Comments: A cytochrome P-450 (heme-thiolate) protein found in plants. Catalyses the first step in the oxidative degradation of abscisic acid and is considered to be the pivotal enzyme in controlling the rate of degradation of this plant hormone [1]. CO inhibits the reaction, but its effects can be reversed by the presence of blue light [1]. The 8′-hydroxyabscisate formed can be converted into (–)-phaseic acid, most probably spontaneously.
References:
1.  Cutler, A.J., Squires, T.M., Loewen, M.K. and Balsevich, J.J. Induction of (+)-abscisic acid 8′ hydroxylase by (+)-abscisic acid in cultured maize cells. J. Exp. Bot. 48 (1997) 1787–1795.
2.  Krochko, J.E., Abrams, G.D., Loewen, M.K., Abrams, S.R. and Cutler, A.J. (+)-Abscisic acid 8′-hydroxylase is a cytochrome P450 monooxygenase. Plant Physiol. 118 (1998) 849–860. [PMID: 9808729]
3.  Saito, S., Hirai, N., Matsumoto, C., Ohigashi, H., Ohta, D., Sakata, K. and Mizutani, M. Arabidopsis CYP707As encode (+)-abscisic acid 8′-hydroxylase, a key enzyme in the oxidative catabolism of abscisic acid. Plant Physiol. 134 (2004) 1439–1449. [PMID: 15064374]
[EC 1.14.14.137 created 2005 as EC 1.14.13.93, transferred 2018 EC 1.14.14.137]
 
 
EC 1.14.14.147     
Accepted name: 22α-hydroxysteroid 23-monooxygenase
Reaction: (1) 3-epi-6-deoxocathasterone + [reduced NADPH—hemoprotein reductase] + O2 = 6-deoxotyphasterol + [oxidized NADPH—hemoprotein reductase] + H2O
(2) (22S,24R)-22-hydroxy-5α-ergostan-3-one + [reduced NADPH—hemoprotein reductase] + O2 = 3-dehydro-6-deoxoteasterone + [oxidized NADPH—hemoprotein reductase] + H2O
Other name(s): cytochrome P450 90C1; CYP90D1; CYP90C1; 3-epi-6-deoxocathasterone,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (C-23-hydroxylating); 3-epi-6-deoxocathasterone 23-monooxygenase
Systematic name: 22α-hydroxysteroid,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (C-23-hydroxylating)
Comments: A cytochrome P-450 (heme-thiolate) protein involved in brassinosteroid biosynthesis in plants. The enzyme has a relaxed substrate specificity, and C-23 hydroxylation can occur at different stages in the pathway. In Arabidopsis thaliana two isozymes, encoded by the CYP90C1 and CYP90D1 genes, have redundant activities.
References:
1.  Kim, G.T., Fujioka, S., Kozuka, T., Tax, F.E., Takatsuto, S., Yoshida, S. and Tsukaya, H. CYP90C1 and CYP90D1 are involved in different steps in the brassinosteroid biosynthesis pathway in Arabidopsis thaliana. Plant J. 41 (2005) 710–721. [PMID: 15703058]
2.  Ohnishi, T., Szatmari, A.M., Watanabe, B., Fujita, S., Bancos, S., Koncz, C., Lafos, M., Shibata, K., Yokota, T., Sakata, K., Szekeres, M. and Mizutani, M. C-23 hydroxylation by Arabidopsis CYP90C1 and CYP90D1 reveals a novel shortcut in brassinosteroid biosynthesis. Plant Cell 18 (2006) 3275–3288. [PMID: 17138693]
[EC 1.14.14.147 created 2010 as EC 1.14.13.112, transferred 2018 to EC 1.14.14.147, modified 2022]
 
 
EC 1.14.14.149     
Accepted name: 5-epiaristolochene 1,3-dihydroxylase
Reaction: 5-epiaristolochene + 2 [reduced NADPH—hemoprotein reductase] + 2 O2 = capsidiol + 2 [oxidized NADPH—hemoprotein reductase] + 2 H2O
Other name(s): 5-epi-aristolochene 1,3-dihydroxylase; EAH; CYP71D20
Systematic name: 5-epiaristolochene,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (1- and 3-hydroxylating)
Comments: A cytochrome P-450 (heme-thiolate) protein. Kinetic studies suggest that 1β-hydroxyepiaristolochene is mainly formed first followed by hydroxylation at C-3. However the reverse order via 3α-hydroxyepiaristolochene does occur.
References:
1.  Ralston, L., Kwon, S.T., Schoenbeck, M., Ralston, J., Schenk, D.J., Coates, R.M. and Chappell, J. Cloning, heterologous expression, and functional characterization of 5-epi-aristolochene-1,3-dihydroxylase from tobacco (Nicotiana tabacum). Arch. Biochem. Biophys. 393 (2001) 222–235. [PMID: 11556809]
2.  Takahashi, S., Zhao, Y., O'Maille, P.E., Greenhagen, B.T., Noel, J.P., Coates, R.M. and Chappell, J. Kinetic and molecular analysis of 5-epiaristolochene 1,3-dihydroxylase, a cytochrome P450 enzyme catalyzing successive hydroxylations of sesquiterpenes. J. Biol. Chem. 280 (2005) 3686–3696. [PMID: 15522862]
[EC 1.14.14.149 created 2011 as EC 1.14.13.119, transferred 2018 to EC 1.14.14.149]
 
 
EC 1.14.14.156     
Accepted name: tryptophan N-monooxygenase
Reaction: L-tryptophan + 2 [reduced NADPH—hemoprotein reductase] + 2 O2 = (E)-indol-3-ylacetaldoxime + 2 [oxidized NADPH—hemoprotein reductase] + CO2 + 3 H2O (overall reaction)
(1a) L-tryptophan + [reduced NADPH—hemoprotein reductase] + O2 = N-hydroxy-L-tryptophan + [oxidized NADPH—hemoprotein reductase] + H2O
(1b) N-hydroxy-L-tryptophan + [reduced NADPH—hemoprotein reductase] + O2 = N,N-dihydroxy-L-tryptophan + [oxidized NADPH—hemoprotein reductase] + H2O
(1c) N,N-dihydroxy-L-tryptophan = (E)-indol-3-ylacetaldoxime + CO2 + H2O
Other name(s): tryptophan N-hydroxylase; CYP79B1; CYP79B2; CYP79B3
Systematic name: L-tryptophan,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (N-hydroxylating)
Comments: A cytochrome P-450 (heme-thiolate) protein from the plant Arabidopsis thaliana. This enzyme catalyses two successive N-hydroxylations of L-tryptophan, the first steps in the biosynthesis of both auxin and the indole alkaloid phytoalexin camalexin. The product of the two hydroxylations, N,N-dihydroxy-L-tryptophan, is extremely labile and dehydrates spontaneously. The dehydrated product is then subject to a decarboxylation that produces an oxime. It is still not known whether the decarboxylation is spontaneous or catalysed by the enzyme.
References:
1.  Mikkelsen, M.D., Hansen, C.H., Wittstock, U. and Halkier, B.A. Cytochrome P450 CYP79B2 from Arabidopsis catalyzes the conversion of tryptophan to indole-3-acetaldoxime, a precursor of indole glucosinolates and indole-3-acetic acid. J. Biol. Chem. 275 (2000) 33712–33717. [PMID: 10922360]
2.  Hull, A.K., Vij, R. and Celenza, J.L. Arabidopsis cytochrome P450s that catalyze the first step of tryptophan-dependent indole-3-acetic acid biosynthesis. Proc. Natl. Acad. Sci. USA 97 (2000) 2379–2384. [PMID: 10681464]
3.  Zhao, Y., Hull, A.K., Gupta, N.R., Goss, K.A., Alonso, J., Ecker, J.R., Normanly, J., Chory, J. and Celenza, J.L. Trp-dependent auxin biosynthesis in Arabidopsis: involvement of cytochrome P450s CYP79B2 and CYP79B3. Genes Dev. 16 (2002) 3100–3112. [PMID: 12464638]
4.  Naur, P., Hansen, C.H., Bak, S., Hansen, B.G., Jensen, N.B., Nielsen, H.L. and Halkier, B.A. CYP79B1 from Sinapis alba converts tryptophan to indole-3-acetaldoxime. Arch. Biochem. Biophys. 409 (2003) 235–241. [PMID: 12464264]
[EC 1.14.14.156 created 2011 as EC 1.14.13.125, transferred 2018 to EC 1.14.14.156]
 
 
EC 1.14.14.158     
Accepted name: carotenoid ε hydroxylase
Reaction: (1) α-carotene + [reduced NADPH-hemoprotein reductase] + O2 = α-cryptoxanthin + [oxidized NADPH-hemoprotein reductase] + H2O
(2) zeinoxanthin + [reduced NADPH-hemoprotein reductase] + O2 = lutein + [oxidized NADPH-hemoprotein reductase] + H2O
Other name(s): CYP97C1; LUT1; CYP97C; carotene ε-monooxygenase
Systematic name: α-carotene,[reduced NADPH-hemoprotein reductase]:oxygen oxidoreductase (3-hydroxylating)
Comments: A cytochrome P-450 (heme-thiolate) protein.
References:
1.  Pogson, B., McDonald, K.A., Truong, M., Britton, G. and DellaPenna, D. Arabidopsis carotenoid mutants demonstrate that lutein is not essential for photosynthesis in higher plants. Plant Cell 8 (1996) 1627–1639. [PMID: 8837513]
2.  Tian, L., Musetti, V., Kim, J., Magallanes-Lundback, M. and DellaPenna, D. The Arabidopsis LUT1 locus encodes a member of the cytochrome P450 family that is required for carotenoid ε-ring hydroxylation activity. Proc. Natl. Acad. Sci. USA 101 (2004) 402–407. [PMID: 14709673]
3.  Stigliani, A.L., Giorio, G. and D'Ambrosio, C. Characterization of P450 carotenoid β- and ε-hydroxylases of tomato and transcriptional regulation of xanthophyll biosynthesis in root, leaf, petal and fruit. Plant Cell Physiol. 52 (2011) 851–865. [PMID: 21450689]
4.  Chang, S., Berman, J., Sheng, Y., Wang, Y., Capell, T., Shi, L., Ni, X., Sandmann, G., Christou, P. and Zhu, C. Cloning and functional characterization of the maize (Zea mays L.) carotenoid ε hydroxylase gene. PLoS One 10:e0128758 (2015). [PMID: 26030746]
5.  Reddy, C.S., Lee, S.H., Yoon, J.S., Kim, J.K., Lee, S.W., Hur, M., Koo, S.C., Meilan, J., Lee, W.M., Jang, J.K., Hur, Y., Park, S.U. and Kim, A.YB. Molecular cloning and characterization of carotenoid pathway genes and carotenoid content in Ixeris dentata var. albiflora. Molecules 22 (2017) . [PMID: 28858245]
[EC 1.14.14.158 created 2011 as EC 1.14.99.45, transferred 2018 to EC 1.14.14.158]
 
 
EC 1.14.14.165     
Accepted name: indole-3-carbonyl nitrile 4-hydroxylase
Reaction: indole-3-carbonyl nitrile + [reduced NADPH—hemoprotein reductase] + O2 = 4-hydroxyindole-3-carbonyl nitrile + [oxidized NADPH—hemoprotein reductase] + H2O
Glossary: indole-3-carbonyl nitrile = 2-(1H-indole-3-yl)-2-oxoacetonitrile
4-hydroxyindole-3-carbonyl nitrile = 2-(4-hydroxy-1H-indole-3-yl)-2-oxoacetonitrile
Other name(s): CYP82C2
Systematic name: indole-3-carbonyl nitrile,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (4-hydroxylating)
Comments: A cytochrome P-450 (heme-thiolate) protein characterized from the plant Arabidopsis thaliana. Involved in biosynthesis of small cyanogenic compounds that take part in pathogen defense. The enzyme also catalyses the 5-hydroxylation of xanthotoxin [1].
References:
1.  Kruse, T., Ho, K., Yoo, H.D., Johnson, T., Hippely, M., Park, J.H., Flavell, R. and Bobzin, S. In planta biocatalysis screen of P450s identifies 8-methoxypsoralen as a substrate for the CYP82C subfamily, yielding original chemical structures. Chem. Biol. 15 (2008) 149–156. [PMID: 18291319]
2.  Rajniak, J., Barco, B., Clay, N.K. and Sattely, E.S. A new cyanogenic metabolite in Arabidopsis required for inducible pathogen defence. Nature 525 (2015) 376–379. [PMID: 26352477]
[EC 1.14.14.165 created 2018]
 
 
EC 1.14.14.178     
Accepted name: steroid 22S-hydroxylase
Reaction: (1) a C27-steroid + O2 + [reduced NADPH—hemoprotein reductase] = a (22S)-22-hydroxy-C27-steroid + 2 H2O + [oxidized NADPH—hemoprotein reductase]
(2) a C28-steroid + O2 + [reduced NADPH—hemoprotein reductase] = a (22S)-22-hydroxy-C28-steroid + 2 H2O + [oxidized NADPH—hemoprotein reductase]
(3) a C29-steroid + O2 + [reduced NADPH—hemoprotein reductase] = a (22S)-22-hydroxy-C29-steroid + 2 H2O + [oxidized NADPH—hemoprotein reductase]
Other name(s): CYP90B1 (gene name); DWF4 (gene name); steroid C-22 hydroxylase
Systematic name: steroid,NADPH—hemoprotein reductase:oxygen 22S-oxidoreductase (hydroxylating)
Comments: This plant cytochrome P-450 (heme thiolate) enzyme participates in the biosynthesis of brassinosteroids. While in vivo substrates include C28-steroids such as campestanol, campesterol, and 6-oxocampestanol, the enzyme is able to catalyse the C-22 hydroxylation of a variety of C27, C28 and C29 steroids.
References:
1.  Asami, T., Mizutani, M., Fujioka, S., Goda, H., Min, Y.K., Shimada, Y., Nakano, T., Takatsuto, S., Matsuyama, T., Nagata, N., Sakata, K. and Yoshida, S. Selective interaction of triazole derivatives with DWF4, a cytochrome P450 monooxygenase of the brassinosteroid biosynthetic pathway, correlates with brassinosteroid deficiency in planta. J. Biol. Chem. 276 (2001) 25687–25691. [PMID: 11319239]
2.  Choe, S., Fujioka, S., Noguchi, T., Takatsuto, S., Yoshida, S. and Feldmann, K.A. Overexpression of DWARF4 in the brassinosteroid biosynthetic pathway results in increased vegetative growth and seed yield in Arabidopsis. Plant J. 26 (2001) 573–582. [PMID: 11489171]
3.  Asami, T., Mizutani, M., Shimada, Y., Goda, H., Kitahata, N., Sekimata, K., Han, S.Y., Fujioka, S., Takatsuto, S., Sakata, K. and Yoshida, S. Triadimefon, a fungicidal triazole-type P450 inhibitor, induces brassinosteroid deficiency-like phenotypes in plants and binds to DWF4 protein in the brassinosteroid biosynthesis pathway. Biochem. J. 369 (2003) 71–76. [PMID: 12350224]
4.  Fujita, S., Ohnishi, T., Watanabe, B., Yokota, T., Takatsuto, S., Fujioka, S., Yoshida, S., Sakata, K. and Mizutani, M. Arabidopsis CYP90B1 catalyses the early C-22 hydroxylation of C27, C28 and C29 sterols. Plant J. 45 (2006) 765–774. [PMID: 16460510]
5.  Ohnishi, T., Watanabe, B., Sakata, K. and Mizutani, M. CYP724B2 and CYP90B3 function in the early C-22 hydroxylation steps of brassinosteroid biosynthetic pathway in tomato. Biosci. Biotechnol. Biochem. 70 (2006) 2071–2080. [PMID: 16960392]
[EC 1.14.14.178 created 2022]
 
 
EC 1.14.15.9     
Accepted name: spheroidene monooxygenase
Reaction: (1) spheroidene + 4 reduced ferredoxin [iron-sulfur] cluster + 2 O2 + 4 H+ = spheroiden-2-one + 4 oxidized ferredoxin [iron-sulfur] cluster + 3 H2O (overall reaction)
(1a) spheroidene + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = 2-hydroxyspheroidene + 2 oxidized ferredoxin [iron-sulfur] cluster + H2O
(1b) 2-hydroxyspheroidene + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = 2,2-dihydroxyspheroidene + 2 oxidized ferredoxin [iron-sulfur] cluster + H2O
(1c) 2,2-dihydroxyspheroidene = spheroiden-2-one + H2O (spontaneous)
(2) spirilloxanthin + 4 reduced ferredoxin [iron-sulfur] cluster + 2 O2 + 4 H+ = 2-oxospirilloxanthin + 4 oxidized ferredoxin [iron-sulfur] cluster + 3 H2O (overall reaction)
(2a) spirilloxanthin + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = 2-hydroxyspirilloxanthin + 2 oxidized ferredoxin [iron-sulfur] cluster + H2O
(2b) 2-hydroxyspirilloxanthin + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = 2,2-dihydroxyspirilloxanthin + 2 oxidized ferredoxin [iron-sulfur] cluster + H2O
(2c) 2,2-dihydroxyspirilloxanthin = 2-oxospirilloxanthin + H2O (spontaneous)
(3) 2-oxospirilloxanthin + 4 reduced ferredoxin [iron-sulfur] cluster + 2 O2 + 4 H+ = 2,2′-dioxospirilloxanthin + 4 oxidized ferredoxin [iron-sulfur] cluster + 3 H2O (overall reaction)
(3a) 2-oxospirilloxanthin + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = 2′-hydroxy-2-oxospirilloxanthin + 2 oxidized ferredoxin [iron-sulfur] cluster + H2O
(3b) 2′-hydroxy-2-oxospirilloxanthin + reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = 2′,2′-dihydroxy-2-oxospirilloxanthin + oxidized ferredoxin [iron-sulfur] cluster + H2O
(3c) 2′,2′-dihydroxy-2-oxospirilloxanthin = 2,2′-dioxospirilloxanthin + H2O (spontaneous)
Glossary: spheroidene = 3,4-didehydro-1-methoxy-1,2,7′,8′-tetrahydro-ψ,ψ-carotene
Other name(s): CrtA; acyclic carotenoid 2-ketolase; spirilloxanthin monooxygenase; 2-oxo-spirilloxanthin monooxygenase
Systematic name: spheroidene,reduced-ferredoxin:oxygen oxidoreductase (spheroiden-2-one-forming)
Comments: The enzyme is involved in spheroidenone biosynthesis and in 2,2′-dioxospirilloxanthin biosynthesis. The enzyme from Rhodobacter sphaeroides contains heme at its active site [1].
References:
1.  Lee, P.C., Holtzapple, E. and Schmidt-Dannert, C. Novel activity of Rhodobacter sphaeroides spheroidene monooxygenase CrtA expressed in Escherichia coli. Appl. Environ. Microbiol. 76 (2010) 7328–7331. [PMID: 20851979]
2.  Gerjets, T., Steiger, S. and Sandmann, G. Catalytic properties of the expressed acyclic carotenoid 2-ketolases from Rhodobacter capsulatus and Rubrivivax gelatinosus. Biochim. Biophys. Acta 1791 (2009) 125–131. [PMID: 19136077]
[EC 1.14.15.9 created 2012, modified 2016]
 
 
EC 1.14.15.17     
Accepted name: pheophorbide a oxygenase
Reaction: pheophorbide a + 2 reduced ferredoxin [iron-sulfur] cluster + 2 H+ + O2 = red chlorophyll catabolite + 2 oxidized ferredoxin [iron-sulfur] cluster (overall reaction)
(1a) pheophorbide a + 2 reduced ferredoxin [iron-sulfur] cluster + 2 H+ + O2 = epoxypheophorbide a + 2 oxidized ferredoxin [iron-sulfur] cluster + H2O
(1b) epoxypheophorbide a + H2O = red chlorophyll catabolite (spontaneous)
Glossary: red chlorophyll catabolite = RCC = (7S,8S,101R)-8-(2-carboxyethyl)-8,23-dihydro-17-ethyl-19-formyl-101-(methoxycarbonyl)-3,7,13,18-tetramethyl-2-vinyl-7H-10,12-ethanobiladiene-ab-1,102(21H)-dione
Other name(s): pheide a monooxygenase; pheide a oxygenase; PaO; PAO
Systematic name: pheophorbide-a,ferredoxin:oxygen oxidoreductase (biladiene-forming)
Comments: This enzyme catalyses a key reaction in chlorophyll degradation, which occurs during leaf senescence and fruit ripening in higher plants. The enzyme from Arabidopsis contains a Rieske-type iron-sulfur cluster [2] and requires reduced ferredoxin, which is generated either by NADPH through the pentose-phosphate pathway or by the action of photosystem I [4]. While still attached to this enzyme, the product is rapidly converted into primary fluorescent chlorophyll catabolite by the action of EC 1.3.7.12, red chlorophyll catabolite reductase [2,6]. Pheophorbide b acts as an inhibitor. In 18O2 labelling experiments, only the aldehyde oxygen is labelled, suggesting that the other oxygen atom may originate from H2O [1].
References:
1.  Hörtensteiner, S., Wüthrich, K.L., Matile, P., Ongania, K.H. and Kräutler, B. The key step in chlorophyll breakdown in higher plants. Cleavage of pheophorbide a macrocycle by a monooxygenase. J. Biol. Chem. 273 (1998) 15335–15339. [PMID: 9624113]
2.  Pružinská, A., Tanner, G., Anders, I., Roca, M. and Hörtensteiner, S. Chlorophyll breakdown: pheophorbide a oxygenase is a Rieske-type iron-sulfur protein, encoded by the accelerated cell death 1 gene. Proc. Natl. Acad. Sci. USA 100 (2003) 15259–15264. [PMID: 14657372]
3.  Chung, D.W., Pružinská, A., Hörtensteiner, S. and Ort, D.R. The role of pheophorbide a oxygenase expression and activity in the canola green seed problem. Plant Physiol. 142 (2006) 88–97. [PMID: 16844830]
4.  Rodoni, S., Mühlecker, W., Anderl, M., Kräutler, B., Moser, D., Thomas, H., Matile, P. and Hörtensteiner, S. Chlorophyll breakdown in senescent chloroplasts. Cleavage of pheophorbide a in two enzymic steps. Plant Physiol. 115 (1997) 669–676. [PMID: 12223835]
5.  Hörtensteiner, S. Chlorophyll degradation during senescence. Annu. Rev. Plant Biol. 57 (2006) 55–77. [PMID: 16669755]
6.  Pružinská, A., Anders, I., Aubry, S., Schenk, N., Tapernoux-Lüthi, E., Müller, T., Kräutler, B. and Hörtensteiner, S. In vivo participation of red chlorophyll catabolite reductase in chlorophyll breakdown. Plant Cell 19 (2007) 369–387. [PMID: 17237353]
[EC 1.14.15.17 created 2007 as EC 1.14.12.20, transferred 2016 to EC 1.14.15.17]
 
 
EC 1.14.15.24     
Accepted name: β-carotene 3-hydroxylase
Reaction: β-carotene + 4 reduced ferredoxin [iron-sulfur] cluster + 2 H+ + 2 O2 = zeaxanthin + 4 oxidized ferredoxin [iron-sulfur] cluster + 2 H2O (overall reaction)
(1a) β-carotene + 2 reduced ferredoxin [iron-sulfur] cluster + H+ + O2 = β-cryptoxanthin + 2 oxidized ferredoxin [iron-sulfur] cluster + H2O
(1b) β-cryptoxanthin + 2 reduced ferredoxin [iron-sulfur] cluster + H+ + O2 = zeaxanthin + 2 oxidized ferredoxin [iron-sulfur] cluster + H2O
Other name(s): β-carotene 3,3′-monooxygenase; CrtZ
Systematic name: β-carotene,reduced ferredoxin [iron-sulfur] cluster:oxygen 3-oxidoreductase
Comments: Requires ferredoxin and Fe(II). Also acts on other carotenoids with a β-end group. In some species canthaxanthin is the preferred substrate.
References:
1.  Sun, Z., Gantt, E. and Cunningham, F.X., Jr. Cloning and functional analysis of the β-carotene hydroxylase of Arabidopsis thaliana. J. Biol. Chem. 271 (1996) 24349–24352. [PMID: 8798688]
2.  Fraser, P.D., Miura, Y. and Misawa, N. In vitro characterization of astaxanthin biosynthetic enzymes. J. Biol. Chem. 272 (1997) 6128–6135. [PMID: 9045623]
3.  Fraser, P.D., Shimada, H. and Misawa, N. Enzymic confirmation of reactions involved in routes to astaxanthin formation, elucidated using a direct substrate in vitro assay. Eur. J. Biochem. 252 (1998) 229–236. [PMID: 9523693]
4.  Bouvier, F., Keller, Y., d'Harlingue, A. and Camara, B. Xanthophyll biosynthesis: molecular and functional characterization of carotenoid hydroxylases from pepper fruits (Capsicum annuum L.). Biochim. Biophys. Acta 1391 (1998) 320–328. [PMID: 9555077]
5.  Linden, H. Carotenoid hydroxylase from Haematococcus pluvialis: cDNA sequence, regulation and functional complementation. Biochim. Biophys. Acta 1446 (1999) 203–212. [PMID: 10524195]
6.  Zhu, C., Yamamura, S., Nishihara, M., Koiwa, H. and Sandmann, G. cDNAs for the synthesis of cyclic carotenoids in petals of Gentiana lutea and their regulation during flower development. Biochim. Biophys. Acta 1625 (2003) 305–308. [PMID: 12591618]
7.  Choi, S.K., Matsuda, S., Hoshino, T., Peng, X. and Misawa, N. Characterization of bacterial β-carotene 3,3′-hydroxylases, CrtZ, and P450 in astaxanthin biosynthetic pathway and adonirubin production by gene combination in Escherichia coli. Appl. Microbiol. Biotechnol. 72 (2006) 1238–1246. [PMID: 16614859]
[EC 1.14.15.24 created 2011 as EC 1.14.13.129, transferred 2017 to EC 1.14.15.24]
 
 
EC 1.14.18.4     
Accepted name: phosphatidylcholine 12-monooxygenase
Reaction: a 1-acyl-2-oleoyl-sn-glycero-3-phosphocholine + 2 ferrocytochrome b5 + O2 + 2 H+ = a 1-acyl-2-[(12R)-12-hydroxyoleoyl]-sn-glycero-3-phosphocholine + 2 ferricytochrome b5 + H2O
Glossary: ricinoleic acid = (9Z,12R)-12-hydroxyoctadec-9-enoic acid
Other name(s): ricinoleic acid synthase; oleate Δ12-hydroxylase; oleate Δ12-monooxygenase
Systematic name: 1-acyl-2-oleoyl-sn-glycero-3-phosphocholine,ferrocytochrome-b5:oxygen oxidoreductase (12-hydroxylating)
Comments: The enzyme, characterized from the plant Ricinus communis (castor bean), is involved in production of the 12-hydroxylated fatty acid ricinoleate. The enzyme, which shares sequence similarity with fatty-acyl desaturases, requires a cytochrome b5 as the electron donor.
References:
1.  Galliard, T. and Stumpf, P.K. Fat metabolism in higher plants. 30. Enzymatic synthesis of ricinoleic acid by a microsomal preparation from developing Ricinus communis seeds. J. Biol. Chem. 241 (1966) 5806–5812. [PMID: 4289003]
2.  Moreau, R.A. and Stumpf, P.K. Recent studies of the enzymic-synthesis of ricinoleic acid by developing castor beans. Plant Physiol. 67 (1981) 672–676. [PMID: 16661734]
3.  Smith, M.A., Jonsson, L., Stymne, S. and Stobart, K. Evidence for cytochrome b5 as an electron donor in ricinoleic acid biosynthesis in microsomal preparations from developing castor bean (Ricinus communis L.). Biochem. J. 287 (1992) 141–144. [PMID: 1417766]
4.  Lin, J.T., McKeon, T.A., Goodrich-Tanrikulu, M. and Stafford, A.E. Characterization of oleoyl-12-hydroxylase in castor microsomes using the putative substrate, 1-acyl-2-oleoyl-sn-glycero-3-phosphocholine. Lipids 31 (1996) 571–577. [PMID: 8784737]
5.  Broun, P. and Somerville, C. Accumulation of ricinoleic, lesquerolic, and densipolic acids in seeds of transgenic Arabidopsis plants that express a fatty acyl hydroxylase cDNA from castor bean. Plant Physiol. 113 (1997) 933–942. [PMID: 9085577]
[EC 1.14.18.4 created 1984 as EC 1.14.13.26, transferred 2015 to EC 1.14.18.4]
 
 
EC 1.14.18.5     
Accepted name: sphingolipid C4-monooxygenase
Reaction: a dihydroceramide + 2 ferrocytochrome b5 + O2 + 2 H+ = a (4R)-4-hydroxysphinganine ceramide + 2 ferricytochrome b5 + H2O
Other name(s): sphinganine C4-monooxygenase; sphingolipid C4-hydroxylase; SUR2 (gene name); SBH1 (gene name); SBH2 (gene name); DEGS2 (gene name)
Systematic name: dihydroceramide,ferrocytochrome b5:oxygen oxidoreductase (C4-hydroxylating)
Comments: The enzyme, which belongs to the familiy of endoplasmic reticular cytochrome b5-dependent enzymes, is involved in the biosynthesis of sphingolipids in eukaryotes. Some enzymes are bifunctional and also catalyse EC 1.14.19.17, sphingolipid 4-desaturase [4].
References:
1.  Haak, D., Gable, K., Beeler, T. and Dunn, T. Hydroxylation of Saccharomyces cerevisiae ceramides requires Sur2p and Scs7p. J. Biol. Chem. 272 (1997) 29704–29710. [PMID: 9368039]
2.  Grilley, M.M., Stock, S.D., Dickson, R.C., Lester, R.L. and Takemoto, J.Y. Syringomycin action gene SYR2 is essential for sphingolipid 4-hydroxylation in Saccharomyces cerevisiae. J. Biol. Chem. 273 (1998) 11062–11068. [PMID: 9556590]
3.  Sperling, P., Ternes, P., Moll, H., Franke, S., Zähringer, U. and Heinz, E. Functional characterization of sphingolipid C4-hydroxylase genes from Arabidopsis thaliana. FEBS Lett. 494 (2001) 90–94. [PMID: 11297741]
4.  Ternes, P., Franke, S., Zähringer, U., Sperling, P. and Heinz, E. Identification and characterization of a sphingolipid Δ4-desaturase family. J. Biol. Chem. 277 (2002) 25512–25518. [PMID: 11937514]
5.  Mizutani, Y., Kihara, A. and Igarashi, Y. Identification of the human sphingolipid C4-hydroxylase, hDES2, and its up-regulation during keratinocyte differentiation. FEBS Lett. 563 (2004) 93–97. [PMID: 15063729]
[EC 1.14.18.5 created 2012 as EC 1.14.13.169, transferred 2015 to EC 1.14.18.5]
 
 
EC 1.14.18.6     
Accepted name: 4-hydroxysphinganine ceramide fatty acyl 2-hydroxylase
Reaction: a phytoceramide + 2 ferrocytochrome b5 + O2 + 2 H+ = a (2′R)-2′-hydroxyphytoceramide + 2 ferricytochrome b5 + H2O
Glossary: a phytoceramide = a (4R)-4-hydroxysphinganine ceramide = an N-acyl-4-hydroxysphinganine
Other name(s): FA2H (gene name); SCS7 (gene name)
Systematic name: (4R)-4-hydroxysphinganine ceramide,ferrocytochrome-b5:oxygen oxidoreductase (fatty acyl 2-hydroxylating)
Comments: The enzyme, characterized from yeast and mammals, catalyses the hydroxylation of carbon 2 of long- or very-long-chain fatty acids attached to (4R)-4-hydroxysphinganine during de novo ceramide synthesis. The enzymes from yeast and from mammals contain an N-terminal cytochrome b5 domain that acts as the direct electron donor to the desaturase active site. The newly introduced 2-hydroxyl group has R-configuration. cf. EC 1.14.18.7, dihydroceramide fatty acyl 2-hydroxylase.
References:
1.  Mitchell, A.G. and Martin, C.E. Fah1p, a Saccharomyces cerevisiae cytochrome b5 fusion protein, and its Arabidopsis thaliana homolog that lacks the cytochrome b5 domain both function in the α-hydroxylation of sphingolipid-associated very long chain fatty acids. J. Biol. Chem. 272 (1997) 28281–28288. [PMID: 9353282]
2.  Dunn, T.M., Haak, D., Monaghan, E. and Beeler, T.J. Synthesis of monohydroxylated inositolphosphorylceramide (IPC-C) in Saccharomyces cerevisiae requires Scs7p, a protein with both a cytochrome b5-like domain and a hydroxylase/desaturase domain. Yeast 14 (1998) 311–321. [PMID: 9559540]
3.  Alderson, N.L., Rembiesa, B.M., Walla, M.D., Bielawska, A., Bielawski, J. and Hama, H. The human FA2H gene encodes a fatty acid 2-hydroxylase. J. Biol. Chem. 279 (2004) 48562–48568. [PMID: 15337768]
4.  Eckhardt, M., Yaghootfam, A., Fewou, S.N., Zoller, I. and Gieselmann, V. A mammalian fatty acid hydroxylase responsible for the formation of α-hydroxylated galactosylceramide in myelin. Biochem. J. 388 (2005) 245–254. [PMID: 15658937]
5.  Guo, L., Zhang, X., Zhou, D., Okunade, A.L. and Su, X. Stereospecificity of fatty acid 2-hydroxylase and differential functions of 2-hydroxy fatty acid enantiomers. J. Lipid Res. 53 (2012) 1327–1335. [PMID: 22517924]
[EC 1.14.18.6 created 2015]
 
 
EC 1.14.18.7     
Accepted name: dihydroceramide fatty acyl 2-hydroxylase
Reaction: a dihydroceramide + 2 ferrocytochrome b5 + O2 + 2 H+ = a (2′R)-2′-hydroxydihydroceramide + 2 ferricytochrome b5 + H2O
Glossary: a dihydroceramide = an N-acylsphinganine
Other name(s): FAH1 (gene name); FAH2 (gene name); plant sphingolipid fatty acid 2-hydroxylase
Systematic name: dihydroceramide,ferrocytochrome-b5:oxygen oxidoreductase (fatty acyl 2-hydroxylating)
Comments: The enzyme, characterized from plants, catalyses the hydroxylation of carbon 2 of long- or very-long-chain fatty acids attached to sphinganine during de novo ceramide synthesis. The enzyme requires an external cytochrome b5 as the electron donor. The newly introduced 2-hydroxyl group has R-configuration. cf. EC 1.14.18.6, 4-hydroxysphinganine ceramide fatty acyl 2-hydroxylase.
References:
1.  Nagano, M., Ihara-Ohori, Y., Imai, H., Inada, N., Fujimoto, M., Tsutsumi, N., Uchimiya, H. and Kawai-Yamada, M. Functional association of cell death suppressor, Arabidopsis Bax inhibitor-1, with fatty acid 2-hydroxylation through cytochrome b5. Plant J. 58 (2009) 122–134. [PMID: 19054355]
2.  Nagano, M., Takahara, K., Fujimoto, M., Tsutsumi, N., Uchimiya, H. and Kawai-Yamada, M. Arabidopsis sphingolipid fatty acid 2-hydroxylases (AtFAH1 and AtFAH2) are functionally differentiated in fatty acid 2-hydroxylation and stress responses. Plant Physiol. 159 (2012) 1138–1148. [PMID: 22635113]
3.  Nagano, M., Uchimiya, H. and Kawai-Yamada, M. Plant sphingolipid fatty acid 2-hydroxylases have unique characters unlike their animal and fungus counterparts. Plant Signal. Behav. 7 (2012) 1388–1392. [PMID: 22918503]
[EC 1.14.18.7 created 2015]
 
 
EC 1.14.18.10     
Accepted name: plant 4,4-dimethylsterol C-4α-methyl-monooxygenase
Reaction: 24-methylidenecycloartanol + 6 ferrocytochrome b5 + 3 O2 + 6 H+ = 3β-hydroxy-4β,14α-dimethyl-9β,19-cyclo-5α-ergost-24(241)-en-4α-carboxylate + 6 ferricytochrome b5 + 4 H2O (overall reaction)
(1a) 24-methylidenecycloartanol + 2 ferrocytochrome b5 + O2 + 2 H+ = 4α-(hydroxymethyl)-4β,14α-dimethyl-9β,19-cyclo-5α-ergost-24(241)-en-3β-ol + 2 ferricytochrome b5 + H2O
(1b) 4α-(hydroxymethyl)-4β,14α-dimethyl-9β,19-cyclo-5α-ergost-24(241)-en-3β-ol + 2 ferrocytochrome b5 + O2 + 2 H+ = 4α-formyl-4β,14α-dimethyl-9β,19-cyclo-5α-ergost-24(241)-en-3β-ol + 2 ferricytochrome b5 + 2 H2O
(1c) 4α-formyl-4β,14α-dimethyl-9β,19-cyclo-5α-ergost-24(241)-en-3β-ol + 2 ferrocytochrome b5 + O2 + 2 H+ = 3β-hydroxy-4β,14α-dimethyl-9β,19-cyclo-5α-ergost-24(241)-en-4α-carboxylate + 2 ferricytochrome b5 + H2O
Glossary: 24-methylidenecycloartanol = 4α,4β,14α-trimethyl-9β,19-cyclo-5α-ergost-24(241)-en-3β-ol
Other name(s): SMO1 (gene name)
Systematic name: 24-methylidenecycloartanol,ferrocytochrome-b5:oxygen oxidoreductase (C-4α-methyl-hydroxylating)
Comments: This plant enzyme catalyses a step in the biosynthesis of sterols. It acts on the 4α-methyl group of the 4,4-dimethylated intermediate 24-methylidenecycloartanol and catalyses three successive oxidations, turning it into a carboxyl group. The carboxylate is subsequently removed by EC 1.1.1.418, plant 3β-hydroxysteroid-4α-carboxylate 3-dehydrogenase (decarboxylating), which also catalyses the epimerization of the remaining 4β-methyl into the 4α position. Unlike the fungal/animal enzyme EC 1.14.18.9, 4α-methylsterol monooxygenase, this enzyme is not able to remove the methyl group from C-4-monomethylated substrates. That activity is performed in plants by a second enzyme, EC 1.14.18.11, plant 4α-monomethylsterol monooxygenase.
References:
1.  Pascal, S., Taton, M. and Rahier, A. Plant sterol biosynthesis. Identification and characterization of two distinct microsomal oxidative enzymatic systems involved in sterol C4-demethylation. J. Biol. Chem. 268 (1993) 11639–11654. [PMID: 8505296]
2.  Rahier, A., Smith, M. and Taton, M. The role of cytochrome b5 in 4α-methyl-oxidation and C5(6) desaturation of plant sterol precursors. Biochem. Biophys. Res. Commun. 236 (1997) 434–437. [PMID: 9240456]
3.  Darnet, S., Bard, M. and Rahier, A. Functional identification of sterol-4α-methyl oxidase cDNAs from Arabidopsis thaliana by complementation of a yeast erg25 mutant lacking sterol-4α-methyl oxidation. FEBS Lett. 508 (2001) 39–43. [PMID: 11707264]
4.  Darnet, S. and Rahier, A. Plant sterol biosynthesis: identification of two distinct families of sterol 4α-methyl oxidases. Biochem. J. 378 (2004) 889–898. [PMID: 14653780]
[EC 1.14.18.10 created 2019]
 
 
EC 1.14.18.11     
Accepted name: plant 4α-monomethylsterol monooxygenase
Reaction: 24-methylidenelophenol + 6 ferrocytochrome b5 + 3 O2 + 6 H+ = 3β-hydroxyergosta-7,24(241)-dien-4α-carboxylate + 6 ferricytochrome b5 + 4 H2O (overall reaction)
(1a) 24-methylidenelophenol + 2 ferrocytochrome b5 + O2 + 2 H+ = 4α-(hydroxymethyl)ergosta-7,24(241)-dien-3β-ol + 2 ferricytochrome b5 + H2O
(1b) 4α-(hydroxymethyl)ergosta-7,24(241)-dien-3β-ol + 2 ferrocytochrome b5 + O2 + 2 H+ = 4α-formylergosta-7,24(241)-dien-3β-ol + 2 ferricytochrome b5 + 2 H2O
(1c) 4α-formylergosta-7,24(241)-dien-3β-ol + 2 ferrocytochrome b5 + O2 + 2 H+ = 3β-hydroxyergosta-7,24(241)-dien-4α-carboxylate + 2 ferricytochrome b5 + H2O
Glossary: 24-methylidenelophenol = 4α-methyl-5α-ergosta-7,24-dien-3β-ol
Other name(s): SMO2 (gene name)
Systematic name: 24-ethylidenelophenol,ferrocytochrome-b5:oxygen oxidoreductase (C-4α-methyl-hydroxylating)
Comments: This plant enzyme catalyses a step in the biosynthesis of sterols. It acts on the methyl group of the 4α-methylated intermediates 24-ethylidenelophenol and 24-methylidenelophenol and catalyses three successive oxidations, turning it into a carboxyl group. The carboxylate is subsequently removed by EC 1.1.1.418, plant 3β-hydroxysteroid-4α-carboxylate 3-dehydrogenase (decarboxylating). Unlike the fungal/animal enzyme EC 1.14.18.9, 4α-methylsterol monooxygenase, this enzyme is not able to act on 4,4-dimethylated substrates. That activity, which occurs earlier in the pathway, is performed in plants by a second enzyme, EC 1.14.18.10, plant 4,4-dimethylsterol C-4α-methyl-monooxygenase.
References:
1.  Pascal, S., Taton, M. and Rahier, A. Plant sterol biosynthesis. Identification and characterization of two distinct microsomal oxidative enzymatic systems involved in sterol C4-demethylation. J. Biol. Chem. 268 (1993) 11639–11654. [PMID: 8505296]
2.  Rahier, A., Smith, M. and Taton, M. The role of cytochrome b5 in 4α-methyl-oxidation and C5(6) desaturation of plant sterol precursors. Biochem. Biophys. Res. Commun. 236 (1997) 434–437. [PMID: 9240456]
3.  Darnet, S., Bard, M. and Rahier, A. Functional identification of sterol-4α-methyl oxidase cDNAs from Arabidopsis thaliana by complementation of a yeast erg25 mutant lacking sterol-4α-methyl oxidation. FEBS Lett. 508 (2001) 39–43. [PMID: 11707264]
4.  Darnet, S. and Rahier, A. Plant sterol biosynthesis: identification of two distinct families of sterol 4α-methyl oxidases. Biochem. J. 378 (2004) 889–898. [PMID: 14653780]
[EC 1.14.18.11 created 2019]
 
 
EC 1.14.19.2     
Accepted name: stearoyl-[acyl-carrier-protein] 9-desaturase
Reaction: stearoyl-[acyl-carrier protein] + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = oleoyl-[acyl-carrier protein] + 2 oxidized ferredoxin [iron-sulfur] cluster + 2 H2O
Other name(s): stearyl acyl carrier protein desaturase; stearyl-ACP desaturase; acyl-[acyl-carrier-protein] desaturase; acyl-[acyl-carrier protein],hydrogen-donor:oxygen oxidoreductase
Systematic name: stearoyl-[acyl-carrier protein],reduced ferredoxin:oxygen oxidoreductase (9,10 cis-dehydrogenating)
Comments: The enzyme is found in the lumen of plastids, where de novo biosynthesis of fatty acids occurs, and acts on freshly synthesized saturated fatty acids that are still linked to acyl-carrier protein. The enzyme determines the position of the double bond by its distance from the carboxylic acid end of the fatty acid. It also acts on palmitoyl-[acyl-carrier-protein] [4,5].
References:
1.  Jaworski, J.G. and Stumpf, P.K. Fat metabolism in higher plants. Properties of a soluble stearyl-acyl carrier protein desaturase from maturing Carthamus tinctorius. Arch. Biochem. Biophys. 162 (1974) 158–165. [PMID: 4831331]
2.  Nagai, J. and Bloch, K. Enzymatic desaturation of stearyl acyl carrier protein. J. Biol. Chem. 243 (1968) 4626–4633. [PMID: 4300868]
3.  Shanklin, J. and Somerville, C. Stearoyl-acyl-carrier-protein desaturase from higher plants is structurally unrelated to the animal and fungal homologs. Proc. Natl. Acad. Sci. USA 88 (1991) 2510–2514. [PMID: 2006187]
4.  Cahoon, E.B., Lindqvist, Y., Schneider, G. and Shanklin, J. Redesign of soluble fatty acid desaturases from plants for altered substrate specificity and double bond position. Proc. Natl. Acad. Sci. USA 94 (1997) 4872–4877. [PMID: 9144157]
5.  Cao, Y., Xian, M., Yang, J., Xu, X., Liu, W. and Li, L. Heterologous expression of stearoyl-acyl carrier protein desaturase (S-ACP-DES) from Arabidopsis thaliana in Escherichia coli. Protein Expr. Purif. 69 (2010) 209–214. [PMID: 19716420]
[EC 1.14.19.2 created 1972 as EC 1.14.99.6, modified 2000, transferred 2000 to EC 1.14.19.2, modified 2015]
 
 
EC 1.14.19.17     
Accepted name: sphingolipid 4-desaturase
Reaction: a dihydroceramide + 2 ferrocytochrome b5 + O2 + 2 H+ = a (4E)-sphing-4-enine ceramide + 2 ferricytochrome b5 + 2 H2O
Glossary: a dihydroceramide = an N-acylsphinganine
Other name(s): dehydroceramide desaturase
Systematic name: dihydroceramide,ferrocytochrome b5:oxygen oxidoreductase (4,5-dehydrogenating)
Comments: The enzyme, which has been characterized from plants, fungi, and mammals, generates a trans double bond at position 4 of sphinganine bases in sphingolipids [1]. The preferred substrate is dihydroceramide, but the enzyme is also active with dihydroglucosylceramide [2]. Unlike EC 1.14.19.29, sphingolipid 8-desaturase, this enzyme does not contain an integral cytochrome b5 domain [4] and requires an external cytochrome b5 [3]. The product serves as an important signalling molecules in mammals and is required for spermatide differentiation [5].
References:
1.  Stoffel, W., Assmann, G. and Bister, K. Metabolism of sphingosine bases. XVII. Stereospecificities in the introduction of the 4t-double bond into sphinganine yielding 4t-sphingenine (sphingosine). Hoppe-Seylers Z. Physiol. Chem. 352 (1971) 1531–1544. [PMID: 5140816]
2.  Michel, C., van Echten-Deckert, G., Rother, J., Sandhoff, K., Wang, E. and Merrill, A.H., Jr. Characterization of ceramide synthesis. A dihydroceramide desaturase introduces the 4,5-trans-double bond of sphingosine at the level of dihydroceramide. J. Biol. Chem. 272 (1997) 22432–22437. [PMID: 9312549]
3.  Causeret, C., Geeraert, L., Van der Hoeven, G., Mannaerts, G.P. and Van Veldhoven, P.P. Further characterization of rat dihydroceramide desaturase: tissue distribution, subcellular localization, and substrate specificity. Lipids 35 (2000) 1117–1125. [PMID: 11104018]
4.  Ternes, P., Franke, S., Zähringer, U., Sperling, P. and Heinz, E. Identification and characterization of a sphingolipid Δ4-desaturase family. J. Biol. Chem. 277 (2002) 25512–25518. [PMID: 11937514]
5.  Michaelson, L.V., Zäuner, S., Markham, J.E., Haslam, R.P., Desikan, R., Mugford, S., Albrecht, S., Warnecke, D., Sperling, P., Heinz, E. and Napier, J.A. Functional characterization of a higher plant sphingolipid Δ4-desaturase: defining the role of sphingosine and sphingosine-1-phosphate in Arabidopsis. Plant Physiol. 149 (2009) 487–498. [PMID: 18978071]
[EC 1.14.19.17 created 2015]
 
 
EC 1.14.19.22     
Accepted name: acyl-lipid ω-6 desaturase (cytochrome b5)
Reaction: an oleoyl-[glycerolipid] + 2 ferrocytochrome b5 + O2 + 2 H+ = a linoleoyl-[glycerolipid] + 2 ferricytochrome b5 + 2 H2O
Other name(s): oleate desaturase (ambiguous); linoleate synthase (ambiguous); oleoyl-CoA desaturase (incorrect); oleoylphosphatidylcholine desaturase (ambiguous); phosphatidylcholine desaturase (ambiguous); n-6 desaturase (ambiguous); FAD2 (gene name)
Systematic name: 1-acyl-2-oleoyl-sn-glycero-3-phosphocholine,ferrocytochrome-b5:oxygen oxidoreductase (12,13 cis-dehydrogenating)
Comments: This microsomal enzyme introduces a cis double bond in fatty acids attached to lipid molecules at a location 6 carbons away from the methyl end of the fatty acid. The distance from the carboxylic acid end of the molecule does not affect the location of the new double bond. The most common substrates are oleoyl groups attached to either the sn-1 or sn-2 position of the glycerol backbone in phosphatidylcholine. cf. EC 1.14.19.23, acyl-lipid ω-6 desaturase (ferredoxin).
References:
1.  Pugh, E.L. and Kates, M. Characterization of a membrane-bound phospholipid desaturase system of Candida lipolytica. Biochim. Biophys. Acta 380 (1975) 442–453. [PMID: 166662]
2.  Slack, C.R., Roughan, P.G. and Browse, J. Evidence for an oleoyl phosphatidylcholine desaturase in microsomal preparations from cotyledons of safflower (Carthamus tinctorius) seed. Biochem. J. 179 (1979) 649–656. [PMID: 475773]
3.  Stymne, S. and Appelqvist, L.-A. The biosynthesis of linoleate from oleoyl-CoA via oleoyl-phosphatidylcholine in microsomes of developing safflower seeds. Eur. J. Biochem. 90 (1978) 223–229. [PMID: 710426]
4.  Smith, M.A., Cross, A.R., Jones, O.T., Griffiths, W.T., Stymne, S. and Stobart, K. Electron-transport components of the 1-acyl-2-oleoyl-sn-glycero-3-phosphocholine Δ12-desaturase (Δ12-desaturase) in microsomal preparations from developing safflower (Carthamus tinctorius L.) cotyledons. Biochem. J. 272 (1990) 23–29. [PMID: 2264826]
5.  Kearns, E.V., Hugly, S. and Somerville, C.R. The role of cytochrome b5 in Δ12 desaturation of oleic acid by microsomes of safflower (Carthamus tinctorius L.). Arch. Biochem. Biophys. 284 (1991) 431–436. [PMID: 1989527]
6.  Miquel, M. and Browse, J. Arabidopsis mutants deficient in polyunsaturated fatty acid synthesis. Biochemical and genetic characterization of a plant oleoyl-phosphatidylcholine desaturase. J. Biol. Chem. 267 (1992) 1502–1509. [PMID: 1730697]
[EC 1.14.19.22 created 1984 as EC 1.3.1.35, transferred 2015 to EC 1.14.19.22]
 
 
EC 1.14.19.23     
Accepted name: acyl-lipid (n+3)-(Z)-desaturase (ferredoxin)
Reaction: an oleoyl-[glycerolipid] + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = a linoleoyl-[glycerolipid] + 2 oxidized ferredoxin [iron-sulfur] cluster + 2 H2O
Other name(s): acyl-lipid ω6-desaturase (ferredoxin); oleate desaturase (ambiguous); linoleate synthase (ambiguous); oleoyl-CoA desaturase (ambiguous); oleoylphosphatidylcholine desaturase (ambiguous); phosphatidylcholine desaturase (ambiguous); FAD6 (gene name)
Systematic name: oleoyl-[glycerolipid],ferredoxin:oxygen oxidoreductase (12,13 cis-dehydrogenating)
Comments: This plastidial enzyme is able to insert a cis double bond in monounsaturated fatty acids incorporated into glycerolipids. The enzyme introduces the new bond at a position 3 carbons away from the existing double bond, towards the methyl end of the fatty acid. The native substrates are oleoyl (18:1 Δ9) and (Z)-hexadec-7-enoyl (16:1 Δ7) groups attached to either position of the glycerol backbone in glycerolipids, resulting in the introduction of the second double bond at positions 12 and 10, respectively This prompted the suggestion that this is an ω6 desaturase. However, when acting on palmitoleoyl groups(16:1 Δ9), the enzyme introduces the second double bond at position 12 (ω4), indicating it is an (n+3) desaturase [3]. cf. EC 1.14.19.34, acyl-lipid (9+3)-(E)-desaturase.
References:
1.  Schmidt, H. and Heinz, E. Desaturation of oleoyl groups in envelope membranes from spinach chloroplasts. Proc. Natl. Acad. Sci. USA 87 (1990) 9477–9480. [PMID: 11607123]
2.  Schmidt, H. and Heinz, E. Involvement of ferredoxin in desaturation of lipid-bound oleate in chloroplasts. Plant Physiol. 94 (1990) 214–220. [PMID: 16667689]
3.  Hitz, W.D., Carlson, T.J., Booth, J.R., Jr., Kinney, A.J., Stecca, K.L. and Yadav, N.S. Cloning of a higher-plant plastid ω-6 fatty acid desaturase cDNA and its expression in a cyanobacterium. Plant Physiol. 105 (1994) 635–641. [PMID: 8066133]
4.  Falcone, D.L., Gibson, S., Lemieux, B. and Somerville, C. Identification of a gene that complements an Arabidopsis mutant deficient in chloroplast ω 6 desaturase activity. Plant Physiol. 106 (1994) 1453–1459. [PMID: 7846158]
5.  Schmidt, H., Dresselhaus, T., Buck, F. and Heinz, E. Purification and PCR-based cDNA cloning of a plastidial n-6 desaturase. Plant Mol. Biol. 26 (1994) 631–642. [PMID: 7948918]
[EC 1.14.19.23 created 2015]
 
 
EC 1.14.19.25     
Accepted name: acyl-lipid ω-3 desaturase (cytochrome b5)
Reaction: a linoleoyl-[glycerolipid] + 2 ferrocytochrome b5 + O2 + 2 H+ = an α-linolenoyl-[glycerolipid] + 2 ferricytochrome b5 + 2 H2O
Glossary: linoleoyl-[glycerolipid] = (9Z,12Z)-octadeca-9,12-dienoyl-[glycerolipid]
α-linolenoyl-[glycerolipid] = (9Z,12Z,15Z)-octadeca-9,12,15-trienoyl-[glycerolipid]
Other name(s): FAD3
Systematic name: (9Z,12Z)-octadeca-9,12-dienoyl-[glycerolipid],ferrocytochrome b5:oxygen oxidoreductase (15,16 cis-dehydrogenating)
Comments: This microsomal enzyme introduces a cis double bond three carbons away from the methyl end of a fatty acid incorporated into a glycerolipid. The distance from the carboxylic acid end of the molecule does not have an effect. The plant enzyme acts on carbon 15 of linoleoyl groups incorporated into both the sn-1 and sn-2 positions of the glycerol backbone of phosphatidylcholine and other phospholipids, converting them into α-linolenoyl groups. The enzyme from the fungus Mortierella alpina acts on γ-linolenoyl and arachidonoyl groups, converting them into stearidonoyl and icosapentaenoyl groups, respectively [3]. cf. EC 1.14.19.35, sn-2 acyl-lipid ω-3 desaturase (ferredoxin).
References:
1.  Browse, J., McConn, M., James, D., Jr. and Miquel, M. Mutants of Arabidopsis deficient in the synthesis of α-linolenate. Biochemical and genetic characterization of the endoplasmic reticulum linoleoyl desaturase. J. Biol. Chem. 268 (1993) 16345–16351. [PMID: 8102138]
2.  Arondel, V., Lemieux, B., Hwang, I., Gibson, S., Goodman, H.M. and Somerville, C.R. Map-based cloning of a gene controlling ω-3 fatty acid desaturation in Arabidopsis. Science 258 (1992) 1353–1355. [PMID: 1455229]
3.  Sakuradani, E., Abe, T., Iguchi, K. and Shimizu, S. A novel fungal ω3-desaturase with wide substrate specificity from arachidonic acid-producing Mortierella alpina 1S-4. Appl. Microbiol. Biotechnol. 66 (2005) 648–654. [PMID: 15538555]
[EC 1.14.19.25 created 2015]
 
 
EC 1.14.19.29     
Accepted name: sphingolipid 8-(E/Z)-desaturase
Reaction: (1) a (4R)-4-hydroxysphinganine ceramide + 2 ferrocytochrome b5 + O2 + 2 H+ = a (4R,8E)-4-hydroxysphing-8-enine ceramide + 2 ferricytochrome b5 + 2 H2O
(2) a (4R)-4-hydroxysphinganine ceramide + 2 ferrocytochrome b5 + O2 + 2 H+ = a (4R,8Z)-4-hydroxysphing-8-enine ceramide + 2 ferricytochrome b5 + 2 H2O
Glossary: a (4R)-4-hydroxysphinganine-ceramide = a phytoceramide
(4R)-4-hydroxysphinganine = phytosphinganine
Other name(s): 8-sphingolipid desaturase (ambiguous); 8 fatty acid desaturase (ambiguous); DELTA8-sphingolipid desaturase (ambiguous)
Systematic name: (4R)-4-hydroxysphinganine ceramide,ferrocytochrome b5:oxygen oxidoreductase (8,9 cis/trans-dehydrogenating)
Comments: The enzymes from higher plants convert sphinganine, 4E-sphing-4-enine and phytosphinganine into E/Z-mixtures of Δ8-desaturated products displaying different proportions of geometrical isomers depending on plant species. The nature of the actual desaturase substrate has not yet been studied experimentally. The enzymes contain an N-terminal cytochrome b5 domain that acts as the direct electron donor to the active site of the desaturase [1]. The homologous enzymes from some yeasts and diatoms, EC 1.14.19.18, sphingolipid 8-(E)-desaturase, act on sphing-4-enine ceramides and produce only the trans isomer.
References:
1.  Sperling, P., Zähringer, U. and Heinz, E. A sphingolipid desaturase from higher plants. Identification of a new cytochrome b5 fusion protein. J. Biol. Chem. 273 (1998) 28590–28596. [PMID: 9786850]
2.  Sperling, P., Blume, A., Zähringer, U., and Heinz, E. Further characterization of Δ8-sphingolipid desaturases from higher plants. Biochem Soc Trans. 28 (2000) 638–641. [PMID: 11171153]
3.  Sperling, P., Libisch, B., Zähringer, U., Napier, J.A. and Heinz, E. Functional identification of a Δ8-sphingolipid desaturase from Borago officinalis. Arch. Biochem. Biophys. 388 (2001) 293–298. [PMID: 11368168]
4.  Beckmann, C., Rattke, J., Oldham, N.J., Sperling, P., Heinz, E. and Boland, W. Characterization of a Δ8-sphingolipid desaturase from higher plants: a stereochemical and mechanistic study on the origin of E,Z isomers. Angew. Chem. Int. Ed. Engl. 41 (2002) 2298–2300. [PMID: 12203571]
5.  Ryan, P.R., Liu, Q., Sperling, P., Dong, B., Franke, S. and Delhaize, E. A higher plant Δ8 sphingolipid desaturase with a preference for (Z)-isomer formation confers aluminum tolerance to yeast and plants. Plant Physiol. 144 (2007) 1968–1977. [PMID: 17600137]
6.  Chen, M., Markham, J.E. and Cahoon, E.B. Sphingolipid Δ8 unsaturation is important for glucosylceramide biosynthesis and low-temperature performance in Arabidopsis. Plant J. 69 (2012) 769–781. [PMID: 22023480]
[EC 1.14.19.29 created 2015]
 
 
EC 1.14.19.35     
Accepted name: sn-2 acyl-lipid ω-3 desaturase (ferredoxin)
Reaction: (1) a (7Z,10Z)-hexadeca-7,10-dienoyl-[glycerolipid] + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = a (7Z,10Z,13Z)-hexadeca-7,10,13-trienoyl-[glycerolipid] + 2 oxidized ferredoxin [iron-sulfur] cluster + 2 H2O
(2) a linoleoyl-[glycerolipid] + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = an α-linolenoyl-[glycerolipid] + 2 oxidized ferredoxin [iron-sulfur] cluster + 2 H2O
Glossary: (9Z,12Z)-octadeca-9,12-dienoyl-[glycerolipid] = linoleoyl-[glycerolipid]
(9Z,12Z,15Z)-octadeca-9,12,15-trienoyl-[glycerolipid] = α-linolenoyl-[glycerolipid]
Other name(s): FAD7; FAD8
Systematic name: (7Z,10Z)-hexadeca-7,10-dienoyl-[glycerolipid],ferredoxin:oxygen oxidoreductase (13,14 cis-dehydrogenating)
Comments: This plastidial enzyme desaturates 16:2 fatty acids attached to the sn-2 position of glycerolipids to 16:3 fatty acids, and converts18:2 to 18:3 in both the sn-1 and sn-2 positions. It acts on all 16:2- or 18:2-containing chloroplast membrane lipids, including phosphatidylglycerol, monogalactosyldiacylglycerol, digalactosyldiaclyglycerol, and sulfoquinovosyldiacylglycerol. The enzyme introduces a cis double bond at a location 3 carbons away from the methyl end of the fatty acid. The distance from the carboxylic acid end of the molecule does not affect the location of the new double bond. cf. EC 1.14.19.25, acyl-lipid ω-3 desaturase (cytochrome b5) and EC 1.14.19.36, sn-1 acyl-lipid ω-3 desaturase (ferredoxin).
References:
1.  Iba, K., Gibson, S., Nishiuchi, T., Fuse, T., Nishimura, M., Arondel, V., Hugly, S. and Somerville, C. A gene encoding a chloroplast ω-3 fatty acid desaturase complements alterations in fatty acid desaturation and chloroplast copy number of the fad7 mutant of Arabidopsis thaliana. J. Biol. Chem. 268 (1993) 24099–24105. [PMID: 8226956]
2.  McConn, M., Hugly, S., Browse, J. and Somerville, C. A mutation at the fad8 locus of Arabidopsis identifies a second chloroplast ω-3 desaturase. Plant Physiol. 106 (1994) 1609–1614. [PMID: 12232435]
3.  Venegas-Caleron, M., Muro-Pastor, A.M., Garces, R. and Martinez-Force, E. Functional characterization of a plastidial ω-3 desaturase from sunflower (Helianthus annuus) in cyanobacteria. Plant Physiol. Biochem. 44 (2006) 517–525. [PMID: 17064923]
[EC 1.14.19.35 created 2015]
 
 
EC 1.14.19.37     
Accepted name: acyl-CoA 5-desaturase
Reaction: (1) (11Z,14Z)-icosa-11,14-dienoyl-CoA + reduced acceptor + O2 = (5Z,11Z,14Z)-icosa-5,11,14-trienoyl-CoA + acceptor + 2 H2O
(2) (11Z,14Z,17Z)-icosa-11,14,17-trienoyl-CoA + reduced acceptor + O2 = (5Z,11Z,14Z,17Z)-icosa-5,11,14,17-tetraenoyl-CoA + acceptor + 2 H2O
Glossary: (5Z,11Z,14Z)-icosa-5,11,14-trienoate = sciadonate
(5Z,11Z,14Z,17Z)-icosa-5,11,14,17-tetraenoate = juniperonate
Other name(s): acyl-CoA 5-desaturase (non-methylene-interrupted)
Systematic name: acyl-CoA,acceptor:oxygen oxidoreductase (5,6 cis-dehydrogenating)
Comments: The enzyme, characterized from the plant Anemone leveillei, introduces a cis double bond at carbon 5 of acyl-CoAs that do not contain a double bond at position 8. In vivo it forms non-methylene-interrupted polyunsaturated fatty acids such as sciadonate and juniperonate. When expressed in Arabidopsis thaliana the enzyme could also act on unsaturated substrates such as palmitoyl-CoA. cf. EC 1.14.19.44, acyl-CoA (8-3)-desaturase.
References:
1.  Sayanova, O., Haslam, R., Venegas Caleron, M. and Napier, J.A. Cloning and characterization of unusual fatty acid desaturases from Anemone leveillei: identification of an acyl-coenzyme A C20 Δ5-desaturase responsible for the synthesis of sciadonic acid. Plant Physiol. 144 (2007) 455–467. [PMID: 17384161]
[EC 1.14.19.37 created 2015]
 
 
EC 1.14.19.41     
Accepted name: sterol 22-desaturase
Reaction: ergosta-5,7,24(28)-trien-3β-ol + NADPH + H+ + O2 = ergosta-5,7,22,24(28)-tetraen-3β-ol + NADP+ + 2 H2O
Other name(s): ERG5 (gene name); CYP710A (gene name)
Systematic name: ergosta-5,7,24(28)-trien-3β-ol,NADPH:oxygen oxidoreductase (22,23-dehydrogenating)
Comments: A heme-thiolate protein (P-450). The enzyme, found in yeast and plants, catalyses the introduction of a double bond between the C-22 and C-23 carbons of certain sterols. In yeast the enzyme acts on ergosta-5,7,24(28)-trien-3β-ol, a step in the biosynthesis of ergosterol. The enzyme from the plant Arabidopsis thaliana acts on sitosterol and 24-epi-campesterol, producing stigmasterol and brassicasterol, respectively.
References:
1.  Kelly, S.L., Lamb, D.C., Corran, A.J., Baldwin, B.C., Parks, L.W. and Kelly, D.E. Purification and reconstitution of activity of Saccharomyces cerevisiae P450 61, a sterol Δ22-desaturase. FEBS Lett. 377 (1995) 217–220. [PMID: 8543054]
2.  Skaggs, B.A., Alexander, J.F., Pierson, C.A., Schweitzer, K.S., Chun, K.T., Koegel, C., Barbuch, R. and Bard, M. Cloning and characterization of the Saccharomyces cerevisiae C-22 sterol desaturase gene, encoding a second cytochrome P-450 involved in ergosterol biosynthesis. Gene 169 (1996) 105–109. [PMID: 8635732]
3.  Morikawa, T., Mizutani, M., Aoki, N., Watanabe, B., Saga, H., Saito, S., Oikawa, A., Suzuki, H., Sakurai, N., Shibata, D., Wadano, A., Sakata, K. and Ohta, D. Cytochrome P450 CYP710A encodes the sterol C-22 desaturase in Arabidopsis and tomato. Plant Cell 18 (2006) 1008–1022. [PMID: 16531502]
[EC 1.14.19.41 created 2015]
 
 
EC 1.14.19.42     
Accepted name: palmitoyl-[glycerolipid] 7-desaturase
Reaction: a 1-acyl-2-palmitoyl-[glycerolipid] + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = a 1-acyl-2-[(7Z)-hexadec-7-enoyl]-[glycerolipid] + 2 oxidized ferredoxin [iron-sulfur] cluster + 2 H2O
Other name(s): FAD5
Systematic name: 1-acyl-2-palmitoyl-[glycerolipid],ferredoxin:oxygen oxidoreductase (7,8-cis-dehydrogenating)
Comments: The enzyme introduces a cis double bond at carbon 7 of a palmitoyl group attached to the sn-2 position of glycerolipids. The enzyme from the plant Arabidopsis thaliana is specific for palmitate in monogalactosyldiacylglycerol.
References:
1.  Kunst, L., Browse, J., Somerville, C.R. A mutant of Arabidopsis deficient in desaturation of palmitic acid in leaf lipids. Plant Physiol. 90 (1989) 943–947. [PMID: 16666902]
2.  Heilmann, I., Mekhedov, S., King, B., Browse, J. and Shanklin, J. Identification of the Arabidopsis palmitoyl-monogalactosyldiacylglycerol Δ7-desaturase gene FAD5, and effects of plastidial retargeting of Arabidopsis desaturases on the fad5 mutant phenotype. Plant Physiol. 136 (2004) 4237–4245. [PMID: 15579662]
[EC 1.14.19.42 created 2015]
 
 
EC 1.14.19.43     
Accepted name: palmitoyl-[glycerolipid] 3-(E)-desaturase
Reaction: a 1-acyl-2-palmitoyl-[glycerolipid] + 2 reduced ferredoxin [iron-sulfur] cluster + O2 + 2 H+ = a 1-acyl-2-[(3E)-hexadec-3-enoyl]-[glycerolipid] + 2 oxidized ferredoxin [iron-sulfur] cluster + 2 H2O
Other name(s): FAD4
Systematic name: 1-acyl-2-palmitoyl-[glycerolipid],ferredoxin:oxygen oxidoreductase (3,4-trans -dehydrogenating)
Comments: The enzyme introduces an unusual trans double bond at carbon 3 of a palmitoyl group attached to the sn-2 position of glycerolipids. The enzyme from the plant Arabidopsis thaliana is specific for palmitate in phosphatidylglycerol. The enzyme from tobacco can also accept oleate and α-linolenate if present at the sn-2 position of phosphatidylglycerol [1].
References:
1.  Fritz, M., Lokstein, H., Hackenberg, D., Welti, R., Roth, M., Zähringer, U., Fulda, M., Hellmeyer, W., Ott, C., Wolter, F.P. and Heinz, E. Channeling of eukaryotic diacylglycerol into the biosynthesis of plastidial phosphatidylglycerol. J. Biol. Chem. 282 (2007) 4613–4625. [PMID: 17158889]
2.  Gao, J., Ajjawi, I., Manoli, A., Sawin, A., Xu, C., Froehlich, J.E., Last, R.L. and Benning, C. FATTY ACID DESATURASE4 of Arabidopsis encodes a protein distinct from characterized fatty acid desaturases. Plant J. 60 (2009) 832–839. [PMID: 19682287]
[EC 1.14.19.43 created 2015]
 
 
EC 1.14.19.52     
Accepted name: camalexin synthase
Reaction: 2-(L-cystein-S-yl)-2-(1H-indol-3-yl)acetonitrile + 2 [reduced NADPH—hemoprotein reductase] + 2 O2 = camalexin + hydrogen cyanide + CO2 + 2 [oxidized NADPH—hemoprotein reductase] + 4 H2O (overall reaction)
(1a) 2-(L-cystein-S-yl)-2-(1H-indol-3-yl)acetonitrile + [reduced NADPH—hemoprotein reductase] + O2 = (R)-dihydrocamalexate + hydrogen cyanide + [oxidized NADPH—hemoprotein reductase] + 2 H2O
(1b) (R)-dihydrocamalexate + [reduced NADPH—hemoprotein reductase] + O2 = camalexin + CO2 + [oxidized NADPH—hemoprotein reductase] + 2 H2O
Glossary: camalexin = 3-(thiazol-2-yl)indole
(R)-dihydrocamalexate = (4R)-2-(1H-indol-3-yl)-4,5-dihydrothiazole-4-carboxylate
Other name(s): CYP71B15 (gene name); bifunctional dihydrocamalexate synthase/camalexin synthase
Systematic name: 2-(cystein-S-yl)-2-(1H-indol-3-yl)-acetonitrile, [reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (camalexin-forming)
Comments: This cytochrome P-450 (heme thiolate) enzyme, which has been characterized from the plant Arabidopsis thaliana, catalyses the last two steps in the biosynthesis of camalexin, the main phytoalexin in that plant. The enzyme catalyses two successive oxidation events. During the first oxidation the enzyme introduces a C-N double bond, liberating hydrogen cyanide, and during the second oxidation it catalyses a decarboxylation.
References:
1.  Schuhegger, R., Nafisi, M., Mansourova, M., Petersen, B.L., Olsen, C.E., Svatos, A., Halkier, B.A. and Glawischnig, E. CYP71B15 (PAD3) catalyzes the final step in camalexin biosynthesis. Plant Physiol. 141 (2006) 1248–1254. [PMID: 16766671]
2.  Böttcher, C., Westphal, L., Schmotz, C., Prade, E., Scheel, D. and Glawischnig, E. The multifunctional enzyme CYP71B15 (PHYTOALEXIN DEFICIENT3) converts cysteine-indole-3-acetonitrile to camalexin in the indole-3-acetonitrile metabolic network of Arabidopsis thaliana. Plant Cell 21 (2009) 1830–1845. [PMID: 19567706]
[EC 1.14.19.52 created 2017]
 
 
EC 1.14.19.75     
Accepted name: very-long-chain acyl-lipid ω-9 desaturase
Reaction: (1) 1-hexacosanoyl-2-acyl-[phosphoglycerolipid] + 2 ferrocytochrome b5 + O2 + 2 H+ = 1-[(17Z)-hexacos-17-enoyl]-2-acyl-[phosphoglycerolipid] + 2 ferricytochrome b5 + 2 H2O
(2) 1-tetracosanoyl-2-acyl-[phosphoglycerolipid] + 2 ferrocytochrome b5 + O2 + 2 H+ = 1-[(15Z)-tetracos-15-enoyl]-2-acyl-[phosphoglycerolipid] + 2 ferricytochrome b5 + 2 H2O
Other name(s): ADS2 (gene name)
Systematic name: very-long-chain acyl-[glycerolipid],ferrocytochrome b5:oxygen oxidoreductase (ω98-cis-dehydrogenating)
Comments: The enzyme, characterized from the plant Arabidopsis thaliana, acts on both 24:0 and 26:0 fatty acids, introducing a cis double bond at a position 9 carbons from the methyl end. These very-long-chain fatty acids are found as a minor component of seed lipids, but also in the membrane phosphatidylethanolamine and phosphatidylserine, in sphingolipids, as precursors and components of cuticular and epicuticular waxes, and in suberin.
References:
1.  Fukuchi-Mizutani, M., Tasaka, Y., Tanaka, Y., Ashikari, T., Kusumi, T. and Murata, N. Characterization of δA9 acyl-lipid desaturase homologues from Arabidopsis thaliana. Plant Cell Physiol. 39 (1998) 247–253. [PMID: 9559566]
2.  Smith, M.A., Dauk, M., Ramadan, H., Yang, H., Seamons, L.E., Haslam, R.P., Beaudoin, F., Ramirez-Erosa, I. and Forseille, L. Involvement of Arabidopsis acyl-coenzyme A desaturase-like2 (At2g31360) in the biosynthesis of the very-long-chain monounsaturated fatty acid components of membrane lipids. Plant Physiol. 161 (2013) 81–96. [PMID: 23175755]
[EC 1.14.19.75 created 2018]
 
 
EC 1.14.19.79     
Accepted name: 3β,22α-dihydroxysteroid 3-dehydrogenase
Reaction: (1) (22S)-22-hydroxycampesterol + [reduced NADPH-hemoprotein reductase] + O2 = (22S)-22-hydroxycampest-4-en-3-one + [oxidized NADPH-hemoprotein reductase] + 2 H2O
(2) 6-deoxoteasterone + [reduced NADPH-hemoprotein reductase] + O2 = 3-dehydro-6-deoxoteasterone + [oxidized NADPH-hemoprotein reductase] + 2 H2O
Glossary: 6-deoxoteasterone = (22R,23R)-5α-campestane-3β,22,23-triol
Other name(s): CYP90A1 (gene name)
Systematic name: 3β,22α-dihydroxysteroid,[reduced NADPH-hemoprotein reductase]:oxygen 3-oxidoreductase
Comments: This cytochrome P-450 (heme-thiolate) enzyme, characterized from the plant Arabidopsis thaliana, catalyses C-3 dehydrogenation of all 3β-hydroxy brassinosteroid synthesis intermediates with 22-hydroxylated or 22,23-dihydroxylated side chains.
References:
1.  Ohnishi, T., Godza, B., Watanabe, B., Fujioka, S., Hategan, L., Ide, K., Shibata, K., Yokota, T., Szekeres, M. and Mizutani, M. CYP90A1/CPD, a brassinosteroid biosynthetic cytochrome P450 of Arabidopsis, catalyzes C-3 oxidation. J. Biol. Chem. 287 (2012) 31551–31560. [PMID: 22822057]
[EC 1.14.19.79 created 2022]
 
 
EC 1.14.20.4     
Accepted name: anthocyanidin synthase
Reaction: a (2R,3S,4S)-leucoanthocyanidin + 2-oxoglutarate + O2 = an anthocyanidin + succinate + CO2 + 2 H2O (overall reaction)
(1a) a (2R,3S,4S)-leucoanthocyanidin + 2-oxoglutarate + O2 = a (4S)- 2,3-dehydroflavan-3,4-diol + succinate + CO2 + H2O
(1b) a (4S)- 2,3-dehydroflavan-3,4-diol = an anthocyanidin + H2O
Glossary: taxifolin = 3,4-dihydroquercitin
Other name(s): leucocyanidin oxygenase; leucocyanidin,2-oxoglutarate:oxygen oxidoreductase; ANS (gene name)
Systematic name: (2R,3S,4S)-leucoanthocyanidin,2-oxoglutarate:oxygen oxidoreductase
Comments: The enzyme requires Fe(II) and ascorbate. It is involved in the pathway by which many flowering plants make anthocyanin flower pigments (glycosylated anthocyandins). The enzyme hydroxylates the C-3 carbon, followed by a trans diaxial elimination, forming a C-2,C-3 enol. The product loses a second water molecule to form anthocyanidins. When assayed in vitro, non-enzymic epimerization of the product can lead to formation of dihydroflavanols. Thus when the substrate is leucocyanidin, a mixture of (+)-taxifolin and (+)-epitaxifolin are formed. The enzyme can also oxidize the formed (+)-taxifolin to quercetin (cf. EC 1.14.20.6, flavonol synthase) [2,3].
References:
1.  Saito, K., Kobayashi, M., Gong, Z., Tanaka, Y. and Yamazaki, M. Direct evidence for anthocyanidin synthase as a 2-oxoglutarate-dependent oxygenase: molecular cloning and functional expression of cDNA from a red forma of Perilla frutescens. Plant J. 17 (1999) 181–190. [PMID: 10074715]
2.  Turnbull, J.J., Sobey, W.J., Aplin, R.T., Hassan, A., Firmin, J.L., Schofield, C.J. and Prescott, A.G. Are anthocyanidins the immediate products of anthocyanidin synthase? Chem. Commun. (2000) 2473–2474.
3.  Wilmouth, R.C., Turnbull, J.J., Welford, R.W., Clifton, I.J., Prescott, A.G. and Schofield, C.J. Structure and mechanism of anthocyanidin synthase from Arabidopsis thaliana. Structure 10 (2002) 93–103. [PMID: 11796114]
4.  Turnbull, J.J., Nagle, M.J., Seibel, J.F., Welford, R.W., Grant, G.H. and Schofield, C.J. The C-4 stereochemistry of leucocyanidin substrates for anthocyanidin synthase affects product selectivity. Bioorg. Med. Chem. Lett. 13 (2003) 3853–3857. [PMID: 14552794]
5.  Wellmann, F., Griesser, M., Schwab, W., Martens, S., Eisenreich, W., Matern, U. and Lukacin, R. Anthocyanidin synthase from Gerbera hybrida catalyzes the conversion of (+)-catechin to cyanidin and a novel procyanidin. FEBS Lett. 580 (2006) 1642–1648. [PMID: 16494872]
[EC 1.14.20.4 created 2001 as EC 1.14.11.19, transferred 2018 to EC 1.14.20.4]
 
 
EC 1.14.99.45      
Transferred entry: carotene ε-monooxygenase. Now EC 1.14.14.158, carotene ε-monooxygenase
[EC 1.14.99.45 created 2011, deleted 2018]
 
 
EC 1.14.99.54     
Accepted name: lytic cellulose monooxygenase (C1-hydroxylating)
Reaction: [(1→4)-β-D-glucosyl]n+m + reduced acceptor + O2 = [(1→4)-β-D-glucosyl]m-1-(1→4)-D-glucono-1,5-lactone + [(1→4)-β-D-glucosyl]n + acceptor + H2O
Other name(s): lytic polysaccharide monooxygenase (ambiguous); LPMO (ambiguous); LPMO9A
Systematic name: cellulose, hydrogen-donor:oxygen oxidoreductase (D-glucosyl C1-hydroxylating)
Comments: This copper-containing enzyme, found in fungi and bacteria, cleaves cellulose in an oxidative manner. The cellulose fragments that are formed contain a D-glucono-1,5-lactone residue at the reducing end, which hydrolyses quickly and spontaneously to the aldonic acid. The electrons are provided in vivo by the cytochrome b domain of EC 1.1.99.18, cellobiose dehydrogenase (acceptor) [1]. Ascorbate can serve as the electron donor in vitro.
References:
1.  Phillips, C.M., Beeson, W.T., Cate, J.H. and Marletta, M.A. Cellobiose dehydrogenase and a copper-dependent polysaccharide monooxygenase potentiate cellulose degradation by Neurospora crassa. ACS Chem. Biol. 6 (2011) 1399–1406. [PMID: 22004347]
2.  Beeson, W.T., Phillips, C.M., Cate, J.H. and Marletta, M.A. Oxidative cleavage of cellulose by fungal copper-dependent polysaccharide monooxygenases. J. Am. Chem. Soc. 134 (2012) 890–892. [PMID: 22188218]
3.  Li, X., Beeson, W.T., 4th, Phillips, C.M., Marletta, M.A. and Cate, J.H. Structural basis for substrate targeting and catalysis by fungal polysaccharide monooxygenases. Structure 20 (2012) 1051–1061. [PMID: 22578542]
4.  Bey, M., Zhou, S., Poidevin, L., Henrissat, B., Coutinho, P.M., Berrin, J.G. and Sigoillot, J.C. Cello-oligosaccharide oxidation reveals differences between two lytic polysaccharide monooxygenases (family GH61) from Podospora anserina. Appl. Environ. Microbiol. 79 (2013) 488–496. [PMID: 23124232]
5.  Frommhagen, M., Sforza, S., Westphal, A.H., Visser, J., Hinz, S.W., Koetsier, M.J., van Berkel, W.J., Gruppen, H. and Kabel, M.A. Discovery of the combined oxidative cleavage of plant xylan and cellulose by a new fungal polysaccharide monooxygenase. Biotechnol. Biofuels 8:101 (2015). [PMID: 26185526]
6.  Patel, I., Kracher, D., Ma, S., Garajova, S., Haon, M., Faulds, C.B., Berrin, J.G., Ludwig, R. and Record, E. Salt-responsive lytic polysaccharide monooxygenases from the mangrove fungus Pestalotiopsis sp. NCi6. Biotechnol Biofuels 9:108 (2016). [PMID: 27213015]
7.  Courtade, G., Wimmer, R., Rohr, A.K., Preims, M., Felice, A.K., Dimarogona, M., Vaaje-Kolstad, G., Sorlie, M., Sandgren, M., Ludwig, R., Eijsink, V.G. and Aachmann, F.L. Interactions of a fungal lytic polysaccharide monooxygenase with β-glucan substrates and cellobiose dehydrogenase. Proc. Natl. Acad. Sci. USA 113 (2016) 5922–5927. [PMID: 27152023]
[EC 1.14.99.54 created 2017]
 
 
EC 1.14.99.56     
Accepted name: lytic cellulose monooxygenase (C4-dehydrogenating)
Reaction: [(1→4)-β-D-glucosyl]n+m + reduced acceptor + O2 = 4-dehydro-β-D-glucosyl-[(1→4)-β-D-glucosyl]n-1 + [(1→4)-β-D-glucosyl]m + acceptor + H2O
Systematic name: cellulose, hydrogen-donor:oxygen oxidoreductase (D-glucosyl 4-dehydrogenating)
Comments: This copper-containing enzyme, found in fungi and bacteria, cleaves cellulose in an oxidative manner. The cellulose fragments that are formed contain a 4-dehydro-D-glucose residue at the non-reducing end. Some enzymes also oxidize cellulose at the C-1 position of the reducing end forming a D-glucono-1,5-lactone residue [cf. EC 1.14.99.54, lytic cellulose monooxygenase (C1-hydroxylating)].
References:
1.  Beeson, W.T., Phillips, C.M., Cate, J.H. and Marletta, M.A. Oxidative cleavage of cellulose by fungal copper-dependent polysaccharide monooxygenases. J. Am. Chem. Soc. 134 (2012) 890–892. [PMID: 22188218]
2.  Li, X., Beeson, W.T., 4th, Phillips, C.M., Marletta, M.A. and Cate, J.H. Structural basis for substrate targeting and catalysis by fungal polysaccharide monooxygenases. Structure 20 (2012) 1051–1061. [PMID: 22578542]
3.  Forsberg, Z., Mackenzie, A.K., Sorlie, M., Rohr, A.K., Helland, R., Arvai, A.S., Vaaje-Kolstad, G. and Eijsink, V.G. Structural and functional characterization of a conserved pair of bacterial cellulose-oxidizing lytic polysaccharide monooxygenases. Proc. Natl. Acad. Sci. USA 111 (2014) 8446–8451. [PMID: 24912171]
4.  Borisova, A.S., Isaksen, T., Dimarogona, M., Kognole, A.A., Mathiesen, G., Varnai, A., Rohr, A.K., Payne, C.M., Sorlie, M., Sandgren, M. and Eijsink, V.G. Structural and functional characterization of a lytic polysaccharide monooxygenase with broad substrate specificity. J. Biol. Chem. 290 (2015) 22955–22969. [PMID: 26178376]
5.  Patel, I., Kracher, D., Ma, S., Garajova, S., Haon, M., Faulds, C.B., Berrin, J.G., Ludwig, R. and Record, E. Salt-responsive lytic polysaccharide monooxygenases from the mangrove fungus Pestalotiopsis sp. NCi6. Biotechnol Biofuels 9:108 (2016). [PMID: 27213015]
[EC 1.14.99.56 created 2017]
 
 
EC 1.14.99.59     
Accepted name: tryptamine 4-monooxygenase
Reaction: tryptamine + reduced acceptor + O2 = 4-hydroxytryptamine + acceptor + H2O
Glossary: psilocybin = 3-[2-(dimethylamino)ethyl]-1H-indol-4-yl phosphate
Other name(s): PsiH
Systematic name: tryptamine,hydrogen-donor:oxygen oxidoreductase (4-hydroxylating)
Comments: A cytochrome P-450 (heme-thiolate) protein isolated from the fungus Psilocybe cubensis. Involved in the biosynthesis of the psychoactive compound psilocybin.
References:
1.  Fricke, J., Blei, F. and Hoffmeister, D. Enzymatic synthesis of psilocybin. Angew. Chem. Int. Ed. Engl. 56 (2017) 12352–12355. [PMID: 28763571]
[EC 1.14.99.59 created 2017]
 
 
EC 1.14.99.64     
Accepted name: zeaxanthin 4-ketolase
Reaction: (1) zeaxanthin + 2 reduced acceptor + 2 O2 = adonixanthin + 2 acceptor + 3 H2O
(2) adonixanthin + 2 reduced acceptor + 2 O2 = (3S,3′S)-astaxanthin + 2 acceptor + 3 H2O
Glossary: zeaxanthin = β,β-carotene-3,3′-diol
adonixanthin = 3,3′-dihydroxy-β,β-carotene-4-one
(3S,3′S)-astaxanthin = (3S,3′S)-3,3′-dihydroxy-β,β-carotene-4,4′-dione
Other name(s): BKT (ambiguous); crtW148 (gene name)
Systematic name: zeaxanthin,donor:oxygen oxidoreductase (adonixanthin-forming)
Comments: The enzyme has a similar activity to that of EC 1.14.99.63, β-carotene 4-ketolase, but unlike that enzyme is able to also act on zeaxanthin.
References:
1.  Zhong, Y.J., Huang, J.C., Liu, J., Li, Y., Jiang, Y., Xu, Z.F., Sandmann, G. and Chen, F. Functional characterization of various algal carotenoid ketolases reveals that ketolating zeaxanthin efficiently is essential for high production of astaxanthin in transgenic Arabidopsis. J. Exp. Bot. 62 (2011) 3659–3669. [PMID: 21398427]
2.  Huang, J., Zhong, Y., Sandmann, G., Liu, J. and Chen, F. Cloning and selection of carotenoid ketolase genes for the engineering of high-yield astaxanthin in plants. Planta 236 (2012) 691–699. [PMID: 22526507]
[EC 1.14.99.64 created 2018]
 
 
EC 1.16.5.1      
Transferred entry: ascorbate ferrireductase (transmembrane). Now EC 7.2.1.3, ascorbate ferrireductase (transmembrane)
[EC 1.16.5.1 created 2011, deleted 2018]
 
 
EC 1.17.7.1     
Accepted name: (E)-4-hydroxy-3-methylbut-2-enyl-diphosphate synthase (ferredoxin)
Reaction: (E)-4-hydroxy-3-methylbut-2-en-1-yl diphosphate + H2O + 2 oxidized ferredoxin = 2-C-methyl-D-erythritol 2,4-cyclodiphosphate + 2 reduced ferredoxin
Other name(s): 4-hydroxy-3-methylbut-2-en-1-yl diphosphate synthase (ambiguous); (E)-4-hydroxy-3-methylbut-2-en-1-yl-diphosphate:protein-disulfide oxidoreductase (hydrating) (incorrect); (E)-4-hydroxy-3-methylbut-2-enyl diphosphate synthase (ambiguous); gcpE (gene name); ISPG (gene name); (E)-4-hydroxy-3-methylbut-2-enyl-diphosphate synthase
Systematic name: (E)-4-hydroxy-3-methylbut-2-en-1-yl-diphosphate:oxidized ferredoxin oxidoreductase
Comments: An iron-sulfur protein found in plant chloroplasts and cyanobacteria that contains a [4Fe-4S] cluster [1]. Forms part of an alternative non-mevalonate pathway for isoprenoid biosynthesis. Bacteria have a similar enzyme that uses flavodoxin rather than ferredoxin (cf. EC 1.17.7.3). The enzyme from the plant Arabidopsis thaliana is active with photoreduced 5-deazaflavin but not with flavodoxin [1].
References:
1.  Okada, K. and Hase, T. Cyanobacterial non-mevalonate pathway: (E)-4-hydroxy-3-methylbut-2-enyl diphosphate synthase interacts with ferredoxin in Thermosynechococcus elongatus BP-1. J. Biol. Chem. 280 (2005) 20672–20679. [PMID: 15792953]
2.  Seemann, M., Wegner, P., Schünemann, V., Tse Sum Bui, B., Wolff, M., Marquet, A., Trautwein, A.X. and Rohmer, M. Isoprenoid biosynthesis in chloroplasts via the methylerythritol phosphate pathway: the (E)-4-hydroxy-3-methylbut-2-enyl diphosphate synthase (GcpE) from Arabidopsis thaliana is a [4Fe-4S] protein. J. Biol. Inorg. Chem. 10 (2005) 131–137. [PMID: 15650872]
3.  Seemann, M., Tse Sum Bui, B., Wolff, M., Tritsch, D., Campos, N., Boronat, A., Marquet, A. and Rohmer, M. Isoprenoid biosynthesis through the methylerythritol phosphate pathway: the (E)-4-hydroxy-3-methylbut-2-enyl diphosphate synthase (GcpE) is a [4Fe-4S] protein. Angew. Chem. Int. Ed. Engl. 41 (2002) 4337–4339. [PMID: 12434382]
4.  Seemann, M., Tse Sum Bui, B., Wolff, M., Miginiac-Maslow, M. and Rohmer, M. Isoprenoid biosynthesis in plant chloroplasts via the MEP pathway: direct thylakoid/ferredoxin-dependent photoreduction of GcpE/IspG. FEBS Lett. 580 (2006) 1547–1552. [PMID: 16480720]
[EC 1.17.7.1 created 2003 as EC 1.17.4.3, transferred 2009 to EC 1.17.7.1, modified 2014]
 
 
EC 1.17.7.2     
Accepted name: 7-hydroxymethyl chlorophyll a reductase
Reaction: chlorophyll a + H2O + 2 oxidized ferredoxin = 71-hydroxychlorophyll a + 2 reduced ferredoxin + 2 H+
Glossary: 71-hydroxychlorophyll a = 7-hydroxymethyl-chlorophyll a
Other name(s): HCAR; 71-hydroxychlorophyll-a:ferredoxin oxidoreductase
Systematic name: chlorophyll-a:ferredoxin oxidoreductase
Comments: Contains FAD and an iron-sulfur center. This enzyme, which is present in plant chloroplasts, carries out the second step in the conversion of chlorophyll b to chlorophyll a. It similarly reduces chlorophyllide a.
References:
1.  Meguro, M., Ito, H., Takabayashi, A., Tanaka, R. and Tanaka, A. Identification of the 7-hydroxymethyl chlorophyll a reductase of the chlorophyll cycle in Arabidopsis. Plant Cell 23 (2011) 3442–3453. [PMID: 21934147]
[EC 1.17.7.2 created 2011]
 
 
EC 1.23.1.3     
Accepted name: (–)-pinoresinol reductase
Reaction: (–)-lariciresinol + NADP+ = (–)-pinoresinol + NADPH + H+
Glossary: (–)-lariciresinol = 4-[(2R,3S,4S)-4-[(4-hydroxy-3-methoxyphenyl)methyl]-3-(hydroxymethyl)oxolan-2-yl]-2-methoxyphenol
(–)-pinoresinol = (1R,3aS,4R,6aS)-4,4′-(tetrahydro-1H,3H-furo[3,4-c]furan-1,4-diyl)bis(2-methoxyphenol)
Other name(s): pinoresinol/lariciresinol reductase; pinoresinol-lariciresinol reductases; (–)-pinoresinol-(–)-lariciresinol reductase; PLR
Systematic name: (–)-lariciresinol:NADP+ oxidoreductase
Comments: The reaction is catalysed in vivo in the opposite direction to that shown. A multifunctional enzyme that usually further reduces the product to (+)-secoisolariciresinol [EC 1.23.1.4, (–)-lariciresinol reductase]. Isolated from the plants Thuja plicata (western red cedar) [1], Linum perenne (perennial flax) [2] and Arabidopsis thaliana (thale cress) [3].
References:
1.  Fujita, M., Gang, D.R., Davin, L.B. and Lewis, N.G. Recombinant pinoresinol-lariciresinol reductases from western red cedar (Thuja plicata) catalyze opposite enantiospecific conversions. J. Biol. Chem. 274 (1999) 618–627. [PMID: 9872995]
2.  Hemmati, S., Schmidt, T.J. and Fuss, E. (+)-Pinoresinol/(-)-lariciresinol reductase from Linum perenne Himmelszelt involved in the biosynthesis of justicidin B. FEBS Lett. 581 (2007) 603–610. [PMID: 17257599]
3.  Nakatsubo, T., Mizutani, M., Suzuki, S., Hattori, T. and Umezawa, T. Characterization of Arabidopsis thaliana pinoresinol reductase, a new type of enzyme involved in lignan biosynthesis. J. Biol. Chem. 283 (2008) 15550–15557. [PMID: 18347017]
[EC 1.23.1.3 created 2013]
 
 
EC 2.1.1.10     
Accepted name: homocysteine S-methyltransferase
Reaction: S-methyl-L-methionine + L-homocysteine = 2 L-methionine
Other name(s): S-adenosylmethionine homocysteine transmethylase; S-methylmethionine homocysteine transmethylase; adenosylmethionine transmethylase; methylmethionine:homocysteine methyltransferase; adenosylmethionine:homocysteine methyltransferase; homocysteine methylase; homocysteine methyltransferase; homocysteine transmethylase; L-homocysteine S-methyltransferase; S-adenosyl-L-methionine:L-homocysteine methyltransferase; S-adenosylmethionine-homocysteine transmethylase; S-adenosylmethionine:homocysteine methyltransferase
Systematic name: S-methyl-L-methionine:L-homocysteine S-methyltransferase
Comments: The enzyme uses S-adenosyl-L-methionine as methyl donor less actively than S-methyl-L-methionine.
References:
1.  Balish, E. and Shapiro, S.K. Methionine biosynthesis in Escherichia coli: induction and repression of methylmethionine (or adenosylmethionine):homocysteine methyltransferase. Arch. Biochem. Biophys. 119 (1967) 62–68. [PMID: 4861151]
2.  Shapiro, S.K. Adenosylmethionine-homocysteine transmethylase. Biochim. Biophys. Acta 29 (1958) 405–409. [PMID: 13572358]
3.  Shapiro, S.K. and Yphantis, D.A. Assay of S-methylmethionine and S-adenosylmethionine homocysteine transmethylases. Biochim. Biophys. Acta 36 (1959) 241–244. [PMID: 14445542]
4.  Mudd, S.H. and Datko, A.H. The S-Methylmethionine Cycle in Lemna paucicostata. Plant Physiol. 93 (1990) 623–630. [PMID: 16667513]
5.  Ranocha, P., McNeil, S.D., Ziemak, M.J., Li, C., Tarczynski, M.C. and Hanson, A.D. The S-methylmethionine cycle in angiosperms: ubiquity, antiquity and activity. Plant J. 25 (2001) 575–584. [PMID: 11309147]
6.  Ranocha, P., Bourgis, F., Ziemak, M.J., Rhodes, D., Gage, D.A. and Hanson, A.D. Characterization and functional expression of cDNAs encoding methionine-sensitive and -insensitive homocysteine S-methyltransferases from Arabidopsis. J. Biol. Chem. 275 (2000) 15962–15968. [PMID: 10747987]
7.  Grue-Sørensen, G., Kelstrup, E., Kjær, A. and Madsen, J.Ø. Diastereospecific, enzymically catalysed transmethylation from S-methyl-L-methionine to L-homocysteine, a naturally occurring process. J. Chem. Soc. Perkin Trans. 1 (1984) 1091–1097.
[EC 2.1.1.10 created 1965, modified 2010]
 
 
EC 2.1.1.35     
Accepted name: tRNA (uracil54-C5)-methyltransferase
Reaction: S-adenosyl-L-methionine + uracil54 in tRNA = S-adenosyl-L-homocysteine + 5-methyluracil54 in tRNA
Other name(s): transfer RNA uracil54 5-methyltransferase; transfer RNA uracil54 methylase; tRNA uracil54 5-methyltransferase; m5U54-methyltransferase; tRNA:m5U54-methyltransferase; RUMT; TrmA; 5-methyluridine54 tRNA methyltransferase; tRNA(uracil-54,C5)-methyltransferase; Trm2; tRNA(m5U54)methyltransferase
Systematic name: S-adenosyl-L-methionine:tRNA (uracil54-C5)-methyltransferase
Comments: Unlike this enzyme, EC 2.1.1.74 (methylenetetrahydrofolate—tRNA-(uracil54-C5)-methyltransferase (FADH2-oxidizing)), uses 5,10-methylenetetrahydrofolate and FADH2 to supply the atoms for methylation of U54 [4].
References:
1.  Björk, G.R. and Svensson, I. Studies on microbial RNA. Fractionation of tRNA methylases from Saccharomyces cerevisiae. Eur. J. Biochem. 9 (1969) 207–215. [PMID: 4896260]
2.  Greenberg, R. and Dudock, B. Isolation and characterization of m5U-methyltransferase from Escherichia coli. J. Biol. Chem. 255 (1980) 8296–8302. [PMID: 6997293]
3.  Hurwitz, J., Gold, M. and Anders, M. The enzymatic methylation of ribonucleic acid and deoxyribonucleic acid. 3. Purification of soluble ribonucleic acid-methylating enzymes. J. Biol. Chem. 239 (1964) 3462–3473. [PMID: 14245404]
4.  Delk, A.S., Nagle, D.P., Jr. and Rabinowitz, J.C. Methylenetetrahydrofolate-dependent biosynthesis of ribothymidine in transfer RNA of Streptococcus faecalis. Evidence for reduction of the 1-carbon unit by FADH2. J. Biol. Chem. 255 (1980) 4387–4390. [PMID: 6768721]
5.  Kealey, J.T., Gu, X. and Santi, D.V. Enzymatic mechanism of tRNA (m5U54)methyltransferase. Biochimie 76 (1994) 1133–1142. [PMID: 7748948]
6.  Gu, X., Ivanetich, K.M. and Santi, D.V. Recognition of the T-arm of tRNA by tRNA (m5U54)-methyltransferase is not sequence specific. Biochemistry 35 (1996) 11652–11659. [PMID: 8794745]
7.  Becker, H.F., Motorin, Y., Sissler, M., Florentz, C. and Grosjean, H. Major identity determinants for enzymatic formation of ribothymidine and pseudouridine in the TΨ-loop of yeast tRNAs. J. Mol. Biol. 274 (1997) 505–518. [PMID: 9417931]
8.  Walbott, H., Leulliot, N., Grosjean, H. and Golinelli-Pimpaneau, B. The crystal structure of Pyrococcus abyssi tRNA (uracil-54, C5)-methyltransferase provides insights into its tRNA specificity. Nucleic Acids Res. 36 (2008) 4929–4940. [PMID: 18653523]
[EC 2.1.1.35 created 1972, modified 2011]
 
 
EC 2.1.1.41     
Accepted name: sterol 24-C-methyltransferase
Reaction: S-adenosyl-L-methionine + 5α-cholesta-8,24-dien-3β-ol = S-adenosyl-L-homocysteine + 24-methylene-5α-cholest-8-en-3β-ol
Glossary: desmosterol = cholesta-5,24-dien-3β-ol
zymostrol = 5α-cholesta-8,24-dien-3β-ol
Other name(s): Δ24-methyltransferase; Δ24-sterol methyltransferase; zymosterol-24-methyltransferase; S-adenosyl-4-methionine:sterol Δ24-methyltransferase; SMT1; 24-sterol C-methyltransferase; S-adenosyl-L-methionine:Δ24(23)-sterol methyltransferase; phytosterol methyltransferase
Systematic name: S-adenosyl-L-methionine:zymosterol 24-C-methyltransferase
Comments: Requires glutathione. Acts on a range of sterols with a 24(25)-double bond in the sidechain. While zymosterol is the preferred substrate it also acts on desmosterol, 5α-cholesta-7,24-dien-3β-ol, 5α-cholesta-5,7,24-trien-3β-ol, 4α-methylzymosterol and others. S-Adenosyl-L-methionine attacks the Si-face of the 24(25) double bond and the C-24 hydrogen is transferred to C-25 on the Re face of the double bond.
References:
1.  Moore, J.T., Jr. and Gaylor, J.L. Isolation and purification of an S-adenosylmethionine: Δ24-sterol methyltransferase from yeast. J. Biol. Chem. 244 (1969) 6334–6340. [PMID: 5354959]
2.  Venkatramesh, M., Guo, D., Jia, Z. and Nes, W.D. Mechanism and structural requirements for transformations of substrates by the S-adenosyl-L-methionine:Δ24(25)-sterol methyl transferase enzyme from Saccharomyces cerevisiae. Biochim. Biophys. Acta 1299 (1996) 313–324. [PMID: 8597586]
3.  Tong, Y., McCourt, B.S., Guo, D., Mangla, A.T., Zhou, W.X., Jenkins, M.D., Zhou, W., Lopez, M. and Nes, W.D. , Stereochemical features of C-methylation on the path to Δ24(28)-methylene and Δ24(28)-ethylidene sterols: studies on the recombinant phytosterol methyl transferase from Arabidopsis thaliana. Tetrahedron Lett. 38 (1997) 6115–6118.
4.  Bouvier-Navé, P., Husselstein, T. and Benveniste, P. Two families of sterol methyltransferases are involved in the first and the second methylation steps of plant biosynthesis. Eur. J. Biochem. 256 (1998) 88–96. [PMID: 9746350]
5.  Nes, W.D., McCourt, B.S., Zhou, W., Ma, J., Marshall, J.A., Peek, L.A. and Brennan, M. Overexpression, purification, and stereochemical studies of the recombinant S-adenosyl-L-methionine:Δ24(25)- to Δ24(28)-sterol methyl transferase enzyme from Saccharomyces cerevisiae sterol methyl transferase. Arch. Biochem. Biophys. 353 (1998) 297–311. [PMID: 9606964]
[EC 2.1.1.41 created 1972, modified 2001]
 
 
EC 2.1.1.42     
Accepted name: flavone 3′-O-methyltransferase
Reaction: S-adenosyl-L-methionine + 3′-hydroxyflavone = S-adenosyl-L-homocysteine + 3′-methoxyflavone
Other name(s): o-dihydric phenol methyltransferase; luteolin methyltransferase; luteolin 3′-O-methyltransferase; o-diphenol m-O-methyltransferase; o-dihydric phenol meta-O-methyltransferase; S-adenosylmethionine:flavone/flavonol 3′-O-methyltransferase; quercetin 3′-O-methyltransferase
Systematic name: S-adenosyl-L-methionine:3′-hydroxyflavone 3′-O-methyltransferase
Comments: The enzyme prefers flavones with vicinal 3′,4′-dihydroxyl groups.
References:
1.  Ebel, J., Hahlbrock, K. and Grisebach, H. Purification and properties of an o-dihydricphenol meta-O-methyltransferase from cell suspension cultures of parsley and its relation to flavonoid biosynthesis. Biochim. Biophys. Acta 268 (1972) 313–326. [PMID: 5026305]
2.  Muzac, I., Wang, J., Anzellotti, D., Zhang, H. and Ibrahim, R.K. Functional expression of an Arabidopsis cDNA clone encoding a flavonol 3′-O-methyltransferase and characterization of the gene product. Arch. Biochem. Biophys. 375 (2000) 385–388. [PMID: 10700397]
3.  Poulton, J.E., Hahlbrock, K. and Grisebach, H. O-Methylation of flavonoid substrates by a partially purified enzyme from soybean cell suspension cultures. Arch. Biochem. Biophys. 180 (1977) 543–549. [PMID: 18099]
4.  Kim, B.G., Lee, H.J., Park, Y., Lim, Y. and Ahn, J.H. Characterization of an O-methyltransferase from soybean. Plant Physiol. Biochem. 44 (2006) 236–241. [PMID: 16777424]
5.  Lee, Y.J., Kim, B.G., Chong, Y., Lim, Y. and Ahn, J.H. Cation dependent O-methyltransferases from rice. Planta 227 (2008) 641–647. [PMID: 17943312]
[EC 2.1.1.42 created 1976, modified 2011]
 
 
EC 2.1.1.74     
Accepted name: methylenetetrahydrofolate—tRNA-(uracil54-C5)-methyltransferase [NAD(P)H-oxidizing]
Reaction: 5,10-methylenetetrahydrofolate + uracil54 in tRNA + NAD(P)H + H+ = tetrahydrofolate + 5-methyluracil54 in tRNA + NAD(P)+
Glossary: Ψ = pseudouridine
T = ribothymidine = 5-methyluridine
Other name(s): folate-dependent ribothymidyl synthase; methylenetetrahydrofolate-transfer ribonucleate uracil 5-methyltransferase; 5,10-methylenetetrahydrofolate:tRNA-UΨC (uracil-5-)-methyl-transferase; 5,10-methylenetetrahydrofolate:tRNA (uracil-5-)-methyl-transferase; TrmFO; folate/FAD-dependent tRNA T54 methyltransferase; methylenetetrahydrofolate—tRNA-(uracil54-C5)-methyltransferase (FADH2-oxidizing)
Systematic name: 5,10-methylenetetrahydrofolate:tRNA (uracil54-C5)-methyltransferase
Comments: A flavoprotein (FAD). Up to 25% of the bases in mature tRNA are post-translationally modified or hypermodified. One almost universal post-translational modification is the conversion of U54 into ribothymidine in the TΨC loop, and this modification is found in most species studied to date [2]. Unlike this enzyme, which uses 5,10-methylenetetrahydrofolate and NAD(P)H to supply the atoms for methylation of U54, EC 2.1.1.35, tRNA (uracil54-C5)-methyltransferase, uses S-adenosyl-L-methionine.
References:
1.  Delk, A.S., Nagle, D.P., Jr. and Rabinowitz, J.C. Methylenetetrahydrofolate-dependent biosynthesis of ribothymidine in transfer RNA of Streptococcus faecalis. Evidence for reduction of the 1-carbon unit by FADH2. J. Biol. Chem. 255 (1980) 4387–4390. [PMID: 6768721]
2.  Becker, H.F., Motorin, Y., Sissler, M., Florentz, C. and Grosjean, H. Major identity determinants for enzymatic formation of ribothymidine and pseudouridine in the TΨ-loop of yeast tRNAs. J. Mol. Biol. 274 (1997) 505–518. [PMID: 9417931]
3.  Nishimasu, H., Ishitani, R., Yamashita, K., Iwashita, C., Hirata, A., Hori, H. and Nureki, O. Atomic structure of a folate/FAD-dependent tRNA T54 methyltransferase. Proc. Natl. Acad. Sci. USA 106 (2009) 8180–8185. [PMID: 19416846]
4.  Yamagami, R., Yamashita, K., Nishimasu, H., Tomikawa, C., Ochi, A., Iwashita, C., Hirata, A., Ishitani, R., Nureki, O. and Hori, H. The tRNA recognition mechanism of folate/FAD-dependent tRNA methyltransferase (TrmFO). J. Biol. Chem. 287 (2012) 42480–42494. [PMID: 23095745]
[EC 2.1.1.74 created 1983 as EC 2.1.2.12, transferred 1984 to EC 2.1.1.74, modified 2011, modified 2019]
 
 
EC 2.1.1.95     
Accepted name: tocopherol C-methyltransferase
Reaction: (1) S-adenosyl-L-methionine + γ-tocopherol = S-adenosyl-L-homocysteine + α-tocopherol
(2) S-adenosyl-L-methionine + δ-tocopherol = S-adenosyl-L-homocysteine + β-tocopherol
(3) S-adenosyl-L-methionine + γ-tocotrienol = S-adenosyl-L-homocysteine + α-tocotrienol
(4) S-adenosyl-L-methionine + δ-tocotrienol = S-adenosyl-L-homocysteine + β-tocotrienol
Other name(s): γ-tocopherol methyltransferase; VTE4 (gene name); S-adenosyl-L-methionine:γ-tocopherol 5-O-methyltransferase (incorrect); tocopherol O-methyltransferase (incorrect)
Systematic name: S-adenosyl-L-methionine:γ-tocopherol 5-C-methyltransferase
Comments: The enzymes from plants and photosynthetic bacteria have similar efficiency with the γ and δ isomers of tocopherols and tocotrienols.
References:
1.  Camara, B. and d'Harlingue, A. Demonstration and solubilization of S-adenosylmethionine: γ-tocopherol methyltransferase from Capsicum chromoplasts. Plant Cell Rep. 4 (1985) 31–32. [PMID: 24253640]
2.  Koch, M., Lemke, R., Heise, K.P. and Mock, H.P. Characterization of γ-tocopherol methyltransferases from Capsicum annuum L and Arabidopsis thaliana. Eur. J. Biochem. 270 (2003) 84–92. [PMID: 12492478]
3.  Zhang, G.Y., Liu, R.R., Xu, G., Zhang, P., Li, Y., Tang, K.X., Liang, G.H. and Liu, Q.Q. Increased α-tocotrienol content in seeds of transgenic rice overexpressing Arabidopsis γ-tocopherol methyltransferase. Transgenic Res. 22 (2013) 89–99. [PMID: 22763462]
[EC 2.1.1.95 created 1989, modified 2013, modified 2019]
 
 
EC 2.1.1.127     
Accepted name: [ribulose-bisphosphate carboxylase]-lysine N-methyltransferase
Reaction: 3 S-adenosyl-L-methionine + [ribulose-1,5-bisphosphate carboxylase]-L-lysine = 3 S-adenosyl-L-homocysteine + [ribulose-1,5-bisphosphate carboxylase]-N6,N6,N6-trimethyl-L-lysine
Other name(s): rubisco methyltransferase; ribulose-bisphosphate-carboxylase/oxygenase N-methyltransferase; ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit εN-methyltransferase; S-adenosyl-L-methionine:[3-phospho-D-glycerate-carboxy-lyase (dimerizing)]-lysine 6-N-methyltransferase; RuBisCO methyltransferase; RuBisCO LSMT
Systematic name: S-adenosyl-L-methionine:[3-phospho-D-glycerate-carboxy-lyase (dimerizing)]-lysine N6-methyltransferase
Comments: The enzyme catalyses three successive methylations of Lys-14 in the large subunits of hexadecameric higher plant ribulose-bisphosphate-carboxylase (EC 4.1.1.39). Only the three methylated form is observed [3]. The enzyme from pea (Pisum sativum) also three-methylates a specific lysine in the chloroplastic isoforms of fructose-bisphosphate aldolase (EC 4.1.2.13) [5].
References:
1.  Wang, P., Royer, M., Houtz, R.L. Affinity purification of ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit εN-methyltransferase. Protein Expr. Purif. 6 (1995) 528–536. [PMID: 8527940]
2.  Ying, Z., Janney, N., Houtz, R.L. Organization and characterization of the ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit N-methyltransferase gene in tobacco. Plant Mol. Biol. 32 (1996) 663–672. [PMID: 8980518]
3.  Dirk, L.M., Flynn, E.M., Dietzel, K., Couture, J.F., Trievel, R.C. and Houtz, R.L. Kinetic manifestation of processivity during multiple methylations catalyzed by SET domain protein methyltransferases. Biochemistry 46 (2007) 3905–3915. [PMID: 17338551]
4.  Magnani, R., Nayak, N.R., Mazarei, M., Dirk, L.M. and Houtz, R.L. Polypeptide substrate specificity of PsLSMT. A set domain protein methyltransferase. J. Biol. Chem. 282 (2007) 27857–27864. [PMID: 17635932]
5.  Mininno, M., Brugiere, S., Pautre, V., Gilgen, A., Ma, S., Ferro, M., Tardif, M., Alban, C. and Ravanel, S. Characterization of chloroplastic fructose 1,6-bisphosphate aldolases as lysine-methylated proteins in plants. J. Biol. Chem. 287 (2012) 21034–21044. [PMID: 22547063]
[EC 2.1.1.127 created 1999, modified 2012]
 
 
EC 2.1.1.165     
Accepted name: methyl halide transferase
Reaction: S-adenosyl-L-methionine + iodide = S-adenosyl-L-homocysteine + methyl iodide
Other name(s): MCT; methyl chloride transferase; S-adenosyl-L-methionine:halide/bisulfide methyltransferase; AtHOL1; AtHOL2; AtHOL3; HARMLESS TO OZONE LAYER protein; HMT; S-adenosyl-L-methionine: halide ion methyltransferase; SAM:halide ion methyltransferase
Systematic name: S-adenosylmethionine:iodide methyltransferase
Comments: This enzyme contributes to the methyl halide emissions from Arabidopsis [6].
References:
1.  Ni, X. and Hager, L.P. Expression of Batis maritima methyl chloride transferase in Escherichia coli. Proc. Natl. Acad. Sci. USA 96 (1999) 3611–3615. [PMID: 10097085]
2.  Saxena, D., Aouad, S., Attieh, J. and Saini, H.S. Biochemical characterization of chloromethane emission from the wood-rotting fungus Phellinus pomaceus. Appl. Environ. Microbiol. 64 (1998) 2831–2835. [PMID: 9687437]
3.  Attieh, J.M., Hanson, A.D. and Saini, H.S. Purification and characterization of a novel methyltransferase responsible for biosynthesis of halomethanes and methanethiol in Brassica oleracea. J. Biol. Chem. 270 (1995) 9250–9257. [PMID: 7721844]
4.  Itoh, N., Toda, H., Matsuda, M., Negishi, T., Taniguchi, T. and Ohsawa, N. Involvement of S-adenosylmethionine-dependent halide/thiol methyltransferase (HTMT) in methyl halide emissions from agricultural plants: isolation and characterization of an HTMT-coding gene from Raphanus sativus (daikon radish). BMC Plant Biol. 9 (2009) 116. [PMID: 19723322]
5.  Ohsawa, N., Tsujita, M., Morikawa, S. and Itoh, N. Purification and characterization of a monohalomethane-producing enzyme S-adenosyl-L-methionine: halide ion methyltransferase from a marine microalga, Pavlova pinguis. Biosci. Biotechnol. Biochem. 65 (2001) 2397–2404. [PMID: 11791711]
6.  Nagatoshi, Y.and Nakamura, T. Characterization of three halide methyltransferases in Arabidopsis thaliana. Plant Biotechnol. 24 (2007) 503–506.
[EC 2.1.1.165 created 2010]
 
 
EC 2.1.1.177     
Accepted name: 23S rRNA (pseudouridine1915-N3)-methyltransferase
Reaction: S-adenosyl-L-methionine + pseudouridine1915 in 23S rRNA = S-adenosyl-L-homocysteine + N3-methylpseudouridine1915 in 23S rRNA
Other name(s): YbeA; RlmH; pseudouridine methyltransferase; m3Ψ methyltransferase; Ψ1915-specific methyltransferase; rRNA large subunit methyltransferase H
Systematic name: S-adenosyl-L-methionine:23S rRNA (pseudouridine1915-N3)-methyltransferase
Comments: YbeA does not methylate uridine at position 1915 [1].
References:
1.  Ero, R., Peil, L., Liiv, A. and Remme, J. Identification of pseudouridine methyltransferase in Escherichia coli. RNA 14 (2008) 2223–2233. [PMID: 18755836]
2.  Purta, E., Kaminska, K.H., Kasprzak, J.M., Bujnicki, J.M. and Douthwaite, S. YbeA is the m3Ψ methyltransferase RlmH that targets nucleotide 1915 in 23S rRNA. RNA 14 (2008) 2234–2244. [PMID: 18755835]
[EC 2.1.1.177 created 2010]
 
 
EC 2.1.1.190     
Accepted name: 23S rRNA (uracil1939-C5)-methyltransferase
Reaction: S-adenosyl-L-methionine + uracil1939 in 23S rRNA = S-adenosyl-L-homocysteine + 5-methyluracil1939 in 23S rRNA
Other name(s): RumA; RNA uridine methyltransferase A; YgcA
Systematic name: S-adenosyl-L-methionine:23S rRNA (uracil1939-C5)-methyltransferase
Comments: The enzyme specifically methylates uracil1939 at C5 in 23S rRNA [1]. The enzyme contains an [4Fe-4S] cluster coordinated by four conserved cysteine residues [2].
References:
1.  Agarwalla, S., Kealey, J.T., Santi, D.V. and Stroud, R.M. Characterization of the 23 S ribosomal RNA m5U1939 methyltransferase from Escherichia coli. J. Biol. Chem. 277 (2002) 8835–8840. [PMID: 11779873]
2.  Lee, T.T., Agarwalla, S. and Stroud, R.M. Crystal structure of RumA, an iron-sulfur cluster containing E. coli ribosomal RNA 5-methyluridine methyltransferase. Structure 12 (2004) 397–407. [PMID: 15016356]
3.  Madsen, C.T., Mengel-Jorgensen, J., Kirpekar, F. and Douthwaite, S. Identifying the methyltransferases for m5U747 and m5U1939 in 23S rRNA using MALDI mass spectrometry. Nucleic Acids Res. 31 (2003) 4738–4746. [PMID: 12907714]
4.  Persaud, C., Lu, Y., Vila-Sanjurjo, A., Campbell, J.L., Finley, J. and O'Connor, M. Mutagenesis of the modified bases, m5U1939 and Ψ2504, in Escherichia coli 23S rRNA. Biochem. Biophys. Res. Commun. 392 (2010) 223–227. [PMID: 20067766]
5.  Agarwalla, S., Stroud, R.M. and Gaffney, B.J. Redox reactions of the iron-sulfur cluster in a ribosomal RNA methyltransferase, RumA: optical and EPR studies. J. Biol. Chem. 279 (2004) 34123–34129. [PMID: 15181002]
6.  Lee, T.T., Agarwalla, S. and Stroud, R.M. A unique RNA Fold in the RumA-RNA-cofactor ternary complex contributes to substrate selectivity and enzymatic function. Cell 120 (2005) 599–611. [PMID: 15766524]
[EC 2.1.1.190 created 2010]
 
 
EC 2.1.1.257     
Accepted name: tRNA (pseudouridine54-N1)-methyltransferase
Reaction: S-adenosyl-L-methionine + pseudouridine54 in tRNA = S-adenosyl-L-homocysteine + N1-methylpseudouridine54 in tRNA
Other name(s): TrmY; m1Ψ methyltransferase
Systematic name: S-adenosyl-L-methionine:tRNA (pseudouridine54-N1)-methyltransferase
Comments: While this archaeal enzyme is specific for the 54 position and does not methylate pseudouridine at position 55, the presence of pseudouridine at position 55 is necessary for the efficient methylation of pseudouridine at position 54 [2,3].
References:
1.  Chen, H.Y. and Yuan, Y.A. Crystal structure of Mj1640/DUF358 protein reveals a putative SPOUT-class RNA methyltransferase. J. Mol. Cell. Biol. 2 (2010) 366–374. [PMID: 21098051]
2.  Wurm, J.P., Griese, M., Bahr, U., Held, M., Heckel, A., Karas, M., Soppa, J. and Wohnert, J. Identification of the enzyme responsible for N1-methylation of pseudouridine 54 in archaeal tRNAs. RNA 18 (2012) 412–420. [PMID: 22274954]
3.  Chatterjee, K., Blaby, I.K., Thiaville, P.C., Majumder, M., Grosjean, H., Yuan, Y.A., Gupta, R. and de Crecy-Lagard, V. The archaeal COG1901/DUF358 SPOUT-methyltransferase members, together with pseudouridine synthase Pus10, catalyze the formation of 1-methylpseudouridine at position 54 of tRNA. RNA 18 (2012) 421–433. [PMID: 22274953]
[EC 2.1.1.257 created 2012]
 
 
EC 2.1.1.259     
Accepted name: [fructose-bisphosphate aldolase]-lysine N-methyltransferase
Reaction: 3 S-adenosyl-L-methionine + [fructose-bisphosphate aldolase]-L-lysine = 3 S-adenosyl-L-homocysteine + [fructose-bisphosphate aldolase]-N6,N6,N6-trimethyl-L-lysine
Other name(s): rubisco methyltransferase; ribulose-bisphosphate-carboxylase/oxygenase N-methyltransferase; ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit εN-methyltransferase; S-adenosyl-L-methionine:[3-phospho-D-glycerate-carboxy-lyase (dimerizing)]-lysine 6-N-methyltransferase
Systematic name: S-adenosyl-L-methionine:[fructose-bisphosphate aldolase]-lysine N6-methyltransferase
Comments: The enzyme methylates a conserved lysine in the C-terminal part of higher plant fructose-bisphosphate aldolase (EC 4.1.2.13). The enzyme from pea (Pisum sativum) also methylates Lys-14 in the large subunits of hexadecameric higher plant ribulose-bisphosphate-carboxylase (EC 4.1.1.39) [2], but that from Arabidopsis thaliana does not.
References:
1.  Magnani, R., Nayak, N.R., Mazarei, M., Dirk, L.M. and Houtz, R.L. Polypeptide substrate specificity of PsLSMT. A set domain protein methyltransferase. J. Biol. Chem. 282 (2007) 27857–27864. [PMID: 17635932]
2.  Mininno, M., Brugiere, S., Pautre, V., Gilgen, A., Ma, S., Ferro, M., Tardif, M., Alban, C. and Ravanel, S. Characterization of chloroplastic fructose 1,6-bisphosphate aldolases as lysine-methylated proteins in plants. J. Biol. Chem. 287 (2012) 21034–21044. [PMID: 22547063]
[EC 2.1.1.259 created 2012]
 
 
EC 2.1.1.260     
Accepted name: rRNA small subunit pseudouridine methyltransferase Nep1
Reaction: S-adenosyl-L-methionine + pseudouridine1191 in yeast 18S rRNA = S-adenosyl-L-homocysteine + N1-methylpseudouridine1191 in yeast 18S rRNA
Other name(s): Nep1; nucleolar essential protein 1
Systematic name: S-adenosyl-L-methionine:18S rRNA (pseudouridine1191-N1)-methyltransferase
Comments: This enzyme, which occurs in both prokaryotes and eukaryotes, recognizes specific pseudouridine residues (Ψ) in small subunits of ribosomal RNA based on the local RNA structure. It recognizes Ψ914 in 16S rRNA from the archaeon Methanocaldococcus jannaschii, Ψ1191 in yeast 18S rRNA, and Ψ1248 in human 18S rRNA.
References:
1.  Taylor, A.B., Meyer, B., Leal, B.Z., Kötter, P., Schirf, V., Demeler, B., Hart, P.J., Entian, K.-D. and Wöhnert, J. The crystal structure of Nep1 reveals an extended SPOUT-class methyltransferase fold and a pre-organized SAM-binding site. Nucleic Acids Res. 36 (2008) 1542–1554. [PMID: 18208838]
2.  Wurm, J.P., Meyer, B., Bahr, U., Held, M., Frolow, O., Kötter, P., Engels, J.W., Heckel, A., Karas, M., Entian, K.-D. and Wöhnert, J. The ribosome assembly factor Nep1 responsible for Bowen-Conradi syndrome is a pseudouridine-N1-specific methyltransferase. Nucleic Acids Res. 38 (2010) 2387–2398. [PMID: 20047967]
3.  Meyer, B., Wurm, J.P., Kötter, P., Leisegang, M.S., Schilling, V., Buchhaupt, M., Held, M., Bahr, U., Karas, M., Heckel, A., Bohnsack, M.T., Wöhnert, J. and Entian, K.-D. The Bowen-Conradi syndrome protein Nep1 (Emg1) has a dual role in eukaryotic ribosome biogenesis, as an essential assembly factor and in the methylation of Ψ1191 in yeast 18S rRNA. Nucleic Acids Res. 39 (2011) 1526–1537. [PMID: 20972225]
[EC 2.1.1.260 created 2012]
 
 
EC 2.1.1.273     
Accepted name: benzoate O-methyltransferase
Reaction: S-adenosyl-L-methionine + benzoate = S-adenosyl-L-homocysteine + methyl benzoate
Other name(s): BAMT; S-adenosyl-L-methionine:benzoic acid carboxyl methyltransferase
Systematic name: S-adenosyl-L-methionine:benzoate O-methyltransferase
Comments: While the enzyme from the plant Zea mays is specific for benzoate [6], the enzymes from Arabidopsis species and Clarkia breweri also catalyse the reaction of EC 2.1.1.274, salicylate 1-O-methyltransferase [1,5]. In snapdragon (Antirrhinum majus) two isoforms are found, one specific for benzoate [2,3] and one that is also active towards salicylate [4]. The volatile product is an important scent compound in some flowering species [2].
References:
1.  Ross, J.R., Nam, K.H., D'Auria, J.C. and Pichersky, E. S-Adenosyl-L-methionine:salicylic acid carboxyl methyltransferase, an enzyme involved in floral scent production and plant defense, represents a new class of plant methyltransferases. Arch. Biochem. Biophys. 367 (1999) 9–16. [PMID: 10375393]
2.  Dudareva, N., Murfitt, L.M., Mann, C.J., Gorenstein, N., Kolosova, N., Kish, C.M., Bonham, C. and Wood, K. Developmental regulation of methyl benzoate biosynthesis and emission in snapdragon flowers. Plant Cell 12 (2000) 949–961. [PMID: 10852939]
3.  Murfitt, L.M., Kolosova, N., Mann, C.J. and Dudareva, N. Purification and characterization of S-adenosyl-L-methionine:benzoic acid carboxyl methyltransferase, the enzyme responsible for biosynthesis of the volatile ester methyl benzoate in flowers of Antirrhinum majus. Arch. Biochem. Biophys. 382 (2000) 145–151. [PMID: 11051108]
4.  Negre, F., Kolosova, N., Knoll, J., Kish, C.M. and Dudareva, N. Novel S-adenosyl-L-methionine:salicylic acid carboxyl methyltransferase, an enzyme responsible for biosynthesis of methyl salicylate and methyl benzoate, is not involved in floral scent production in snapdragon flowers. Arch. Biochem. Biophys. 406 (2002) 261–270. [PMID: 12361714]
5.  Chen, F., D'Auria, J.C., Tholl, D., Ross, J.R., Gershenzon, J., Noel, J.P. and Pichersky, E. An Arabidopsis thaliana gene for methylsalicylate biosynthesis, identified by a biochemical genomics approach, has a role in defense. Plant J. 36 (2003) 577–588. [PMID: 14617060]
6.  Köllner, T.G., Lenk, C., Zhao, N., Seidl-Adams, I., Gershenzon, J., Chen, F. and Degenhardt, J. Herbivore-induced SABATH methyltransferases of maize that methylate anthranilic acid using s-adenosyl-L-methionine. Plant Physiol. 153 (2010) 1795–1807. [PMID: 20519632]
[EC 2.1.1.273 created 2013]
 
 
EC 2.1.1.274     
Accepted name: salicylate 1-O-methyltransferase
Reaction: S-adenosyl-L-methionine + salicylate = S-adenosyl-L-homocysteine + methyl salicylate
Glossary: methyl salicylate = methyl 2-hydroxybenzoate
Other name(s): SAMT; S-adenosyl-L-methionine:salicylic acid carboxyl methyltransferase; salicylate carboxymethyltransferase
Systematic name: S-adenosyl-L-methionine:salicylate 1-O-methyltransferase
Comments: The enzyme, which is found in flowering plants, also has the activity of EC 2.1.1.273, benzoate O-methyltransferase.
References:
1.  Ross, J.R., Nam, K.H., D'Auria, J.C. and Pichersky, E. S-Adenosyl-L-methionine:salicylic acid carboxyl methyltransferase, an enzyme involved in floral scent production and plant defense, represents a new class of plant methyltransferases. Arch. Biochem. Biophys. 367 (1999) 9–16. [PMID: 10375393]
2.  Negre, F., Kolosova, N., Knoll, J., Kish, C.M. and Dudareva, N. Novel S-adenosyl-L-methionine:salicylic acid carboxyl methyltransferase, an enzyme responsible for biosynthesis of methyl salicylate and methyl benzoate, is not involved in floral scent production in snapdragon flowers. Arch. Biochem. Biophys. 406 (2002) 261–270. [PMID: 12361714]
3.  Chen, F., D'Auria, J.C., Tholl, D., Ross, J.R., Gershenzon, J., Noel, J.P. and Pichersky, E. An Arabidopsis thaliana gene for methylsalicylate biosynthesis, identified by a biochemical genomics approach, has a role in defense. Plant J. 36 (2003) 577–588. [PMID: 14617060]
4.  Zubieta, C., Ross, J.R., Koscheski, P., Yang, Y., Pichersky, E. and Noel, J.P. Structural basis for substrate recognition in the salicylic acid carboxyl methyltransferase family. Plant Cell 15 (2003) 1704–1716. [PMID: 12897246]
[EC 2.1.1.274 created 2013]
 
 
EC 2.1.1.275     
Accepted name: gibberellin A9 O-methyltransferase
Reaction: S-adenosyl-L-methionine + gibberellin A9 = S-adenosyl-L-homocysteine + methyl gibberellin A9
Glossary: gibberellin A9 = (1R,4aR,4bR,7R,9aR,10S,10aR)-1-methyl-8-methylene-13-oxododecahydro-4a,1-(epoxymethano)-7,9a-methanobenzo[a]azulene-10-carboxylic acid
methyl gibberellin A9 = methyl (1R,4aR,4bR,7R,9aR,10S,10aR)-1-methyl-8-methylene-13-oxododecahydro-4a,1-(epoxymethano)-7,9a-methanobenzo[a]azulene-10-carboxylate
Other name(s): GAMT1
Systematic name: S-adenosyl-L-methionine:gibberellin A9 O-methyltransferase
Comments: The enzyme also methylates gibberellins A20 (95%), A3 (80%), A4 (69%) and A34 (46%) with significant activity.
References:
1.  Varbanova, M., Yamaguchi, S., Yang, Y., McKelvey, K., Hanada, A., Borochov, R., Yu, F., Jikumaru, Y., Ross, J., Cortes, D., Ma, C.J., Noel, J.P., Mander, L., Shulaev, V., Kamiya, Y., Rodermel, S., Weiss, D. and Pichersky, E. Methylation of gibberellins by Arabidopsis GAMT1 and GAMT2. Plant Cell 19 (2007) 32–45. [PMID: 17220201]
[EC 2.1.1.275 created 2013]
 
 
EC 2.1.1.276     
Accepted name: gibberellin A4 carboxyl methyltransferase
Reaction: S-adenosyl-L-methionine + gibberellin A4 = S-adenosyl-L-homocysteine + methyl gibberellin A4
Glossary: gibberellin A4 = (1S,2S,4aR,4bR,7R,9aR,10S,10aR)-2-hydroxy-1-methyl-8-methylidene-13-oxododecahydro-4a,1-(epoxymethano)-7,9a-methanobenzo[a]azulene-10-carboxylic acid
methyl gibberellin A4 = methyl (1S,2S,4aR,4bR,7R,9aR,10S,10aR)-2-hydroxy-1-methyl-8-methylene-13-oxododecahydro-4a,1-(epoxymethano)-7,9a-methanobenzo[a]azulene-10-carboxylate
Other name(s): GAMT2; gibberellin A4 O-methyltransferase
Systematic name: S-adenosyl-L-methionine:gibberellin A4 O-methyltransferase
Comments: The enzyme also methylates gibberellins A34 (80%), A9 (60%), and A3 (45%) with significant activity.
References:
1.  Varbanova, M., Yamaguchi, S., Yang, Y., McKelvey, K., Hanada, A., Borochov, R., Yu, F., Jikumaru, Y., Ross, J., Cortes, D., Ma, C.J., Noel, J.P., Mander, L., Shulaev, V., Kamiya, Y., Rodermel, S., Weiss, D. and Pichersky, E. Methylation of gibberellins by Arabidopsis GAMT1 and GAMT2. Plant Cell 19 (2007) 32–45. [PMID: 17220201]
[EC 2.1.1.276 created 2013]
 
 
EC 2.1.1.278     
Accepted name: indole-3-acetate O-methyltransferase
Reaction: S-adenosyl-L-methionine + (indol-3-yl)acetate = S-adenosyl-L-homocysteine + methyl (indol-3-yl)acetate
Other name(s): IAA carboxylmethyltransferase; IAMT
Systematic name: S-adenosyl-L-methionine:(indol-3-yl)acetate O-methyltransferase
Comments: Binds Mg2+. The enzyme is found in plants and is important for regulation of the plant hormone (indol-3-yl)acetate. The product, methyl (indol-3-yl)acetate is inactive as hormone [2].
References:
1.  Zubieta, C., Ross, J.R., Koscheski, P., Yang, Y., Pichersky, E. and Noel, J.P. Structural basis for substrate recognition in the salicylic acid carboxyl methyltransferase family. Plant Cell 15 (2003) 1704–1716. [PMID: 12897246]
2.  Li, L., Hou, X., Tsuge, T., Ding, M., Aoyama, T., Oka, A., Gu, H., Zhao, Y. and Qu, L.J. The possible action mechanisms of indole-3-acetic acid methyl ester in Arabidopsis. Plant Cell Rep. 27 (2008) 575–584. [PMID: 17926040]
3.  Zhao, N., Ferrer, J.L., Ross, J., Guan, J., Yang, Y., Pichersky, E., Noel, J.P. and Chen, F. Structural, biochemical, and phylogenetic analyses suggest that indole-3-acetic acid methyltransferase is an evolutionarily ancient member of the SABATH family. Plant Physiol. 146 (2008) 455–467. [PMID: 18162595]
[EC 2.1.1.278 created 2013]
 
 
EC 2.1.1.292     
Accepted name: carminomycin 4-O-methyltransferase
Reaction: S-adenosyl-L-methionine + carminomycin = S-adenosyl-L-homocysteine + daunorubicin
Glossary: daunorubicin = (+)-daunomycin = (8S,10S)-8-acetyl-10-[(2S,4S,5S,6S)-4-amino-5-hydroxy-6-methyloxan-2-yl]oxy-6,8,11-trihydroxy-1-methoxy-9,10-dihydro-7H-tetracene-5,12-dione
carminomycin = (1S,3S)-3-acetyl-3,5,10,12-tetrahydroxy-6,11-dioxo-1,2,3,4,6,11-hexahydrotetracen-1-yl 3-amino-2,3,6-trideoxy-α-L-lyxo-hexopyranoside = (1S,3S)-3-acetyl-3,5,10,12-tetrahydroxy-6,11-dioxo-1,2,3,4,6,11-hexahydronaphthacen-1-yl 3-amino-2,3,6-trideoxy-α-L-lyxo-hexopyranoside
carubicin = (1S,3S)-3-acetyl-3,5,12-trihydroxy-10-methoxy-6,11-dioxo-1,2,3,4,6,11-hexahydrotetracen-1-yl 3-amino-2,3,6-trideoxy-α-L-lyxo-hexopyranoside
= (8S,10S)-8-acetyl-10-[(3-amino-2,3,6-trideoxy-α-L-lyxo-hexopyranosyl)oxy]-6,8,11-trihydroxy-1-methoxy-7,8,9,10-tetrahydronaphthacene-5,12-dione
Other name(s): DnrK; DauK
Systematic name: S-adenosyl-L-methionine:carminomycin 4-O-methyltransferase
Comments: The enzymes from the Gram-positive bacteria Streptomyces sp. C5 and Streptomyces peucetius are involved in the biosynthesis of the anthracycline daunorubicin. In vitro the enzyme from Streptomyces sp. C5 also catalyses the 4-O-methylation of 13-dihydrocarminomycin, rhodomycin D and 10-carboxy-13-deoxycarminomycin [3].
References:
1.  Connors, N.C. and Strohl, W.R. Partial purification and properties of carminomycin 4-O-methyltransferase from Streptomyces sp. strain C5. J. Gen. Microbiol. 139 Pt 6 (1993) 1353–1362. [PMID: 8360627]
2.  Jansson, A., Koskiniemi, H., Mantsala, P., Niemi, J. and Schneider, G. Crystal structure of a ternary complex of DnrK, a methyltransferase in daunorubicin biosynthesis, with bound products. J. Biol. Chem. 279 (2004) 41149–41156. [PMID: 15273252]
3.  Dickens, M.L., Priestley, N.D. and Strohl, W.R. In vivo and in vitro bioconversion of ε-rhodomycinone glycoside to doxorubicin: functions of DauP, DauK, and DoxA. J. Bacteriol. 179 (1997) 2641–2650. [PMID: 9098063]
[EC 2.1.1.292 created 2013]
 
 
EC 2.1.1.295     
Accepted name: 2-methyl-6-phytyl-1,4-hydroquinone methyltransferase
Reaction: (1) S-adenosyl-L-methionine + 2-methyl-6-phytylbenzene-1,4-diol = S-adenosyl-L-homocysteine + 2,3-dimethyl-6-phytylbenzene-1,4-diol
(2) S-adenosyl-L-methionine + 2-methyl-6-all-trans-nonaprenylbenzene-1,4-diol = S-adenosyl-L-homocysteine + plastoquinol
(3) S-adenosyl-L-methionine + 6-geranylgeranyl-2-methylbenzene-1,4-diol = S-adenosyl-L-homocysteine + 6-geranylgeranyl-2,3-dimethylbenzene-1,4-diol
Other name(s): VTE3 (gene name); 2-methyl-6-solanyl-1,4-hydroquinone methyltransferase; MPBQ/MSBQ methyltransferase; MPBQ/MSBQ MT
Systematic name: S-adenosyl-L-methionine:2-methyl-6-phytyl-1,4-benzoquinol C-3-methyltransferase
Comments: Involved in the biosynthesis of plastoquinol, as well as vitamin E (tocopherols and tocotrienols).
References:
1.  Shintani, D.K., Cheng, Z. and DellaPenna, D. The role of 2-methyl-6-phytylbenzoquinone methyltransferase in determining tocopherol composition in Synechocystis sp. PCC6803. FEBS Lett. 511 (2002) 1–5. [PMID: 11821038]
2.  Cheng, Z., Sattler, S., Maeda, H., Sakuragi, Y., Bryant, D.A. and DellaPenna, D. Highly divergent methyltransferases catalyze a conserved reaction in tocopherol and plastoquinone synthesis in cyanobacteria and photosynthetic eukaryotes. Plant Cell 15 (2003) 2343–2356. [PMID: 14508009]
3.  Van Eenennaam, A.L., Lincoln, K., Durrett, T.P., Valentin, H.E., Shewmaker, C.K., Thorne, G.M., Jiang, J., Baszis, S.R., Levering, C.K., Aasen, E.D., Hao, M., Stein, J.C., Norris, S.R. and Last, R.L. Engineering vitamin E content: from Arabidopsis mutant to soy oil. Plant Cell 15 (2003) 3007–3019. [PMID: 14630966]
[EC 2.1.1.295 created 2014]
 
 
EC 2.1.1.301     
Accepted name: cypemycin N-terminal methyltransferase
Reaction: 2 S-adenosyl-L-methionine + N-terminal L-alanine-[cypemycin] = 2 S-adenosyl-L-homocysteine + N-terminal N,N-dimethyl-L-alanine-[cypemycin]
Other name(s): CypM
Systematic name: S-adenosyl-L-methionine:N-terminal L-alanine-[cypemycin] N-methyltransferase
Comments: The enzyme, isolated from the bacterium Streptomyces sp. OH-4156, can methylate a variety of linear oligopeptides, cyclic peptides such as nisin and haloduracin, and the ε-amino group of lysine [2]. Cypemycin is a peptide antibiotic, a member of the linaridins, a class of posttranslationally modified ribosomally synthesized peptides.
References:
1.  Claesen, J. and Bibb, M. Genome mining and genetic analysis of cypemycin biosynthesis reveal an unusual class of posttranslationally modified peptides. Proc. Natl. Acad. Sci. USA 107 (2010) 16297–16302. [PMID: 20805503]
2.  Zhang, Q. and van der Donk, W.A. Catalytic promiscuity of a bacterial α-N-methyltransferase. FEBS Lett. 586 (2012) 3391–3397. [PMID: 22841713]
[EC 2.1.1.301 created 2014]
 
 
EC 2.1.1.315     
Accepted name: 27-O-demethylrifamycin SV methyltransferase
Reaction: S-adenosyl-L-methionine + 27-O-demethylrifamycin SV = S-adenosyl-L-homocysteine + rifamycin SV
Glossary: rifamycin SV = (7S,9E,11S,12R,13S,14R,15R,16R,17S,18S,19E,21Z)-2,15,17,27,29-pentahydroxy-11-methoxy-3,7,12,14,16,18,22-heptamethyl-6,23-dioxo-8,30-dioxa-24-azatetracyclo[23.3.1.14,7.05,28]triaconta-1(28),2,4,9, 19,21,25(29),26-octaen-13-yl acetate
Other name(s): AdoMet:27-O-demethylrifamycin SV methyltransferase
Systematic name: S-adenosyl-L-methionine:27-O-demethylrifamycin-SV 27-O-methyltransferase
Comments: The enzyme, characterized from the bacterium Amycolatopsis mediterranei, is involved in biosynthesis of the antitubercular drug rifamycin B.
References:
1.  Xu, J., Mahmud, T. and Floss, H.G. Isolation and characterization of 27-O-demethylrifamycin SV methyltransferase provides new insights into the post-PKS modification steps during the biosynthesis of the antitubercular drug rifamycin B by Amycolatopsis mediterranei S699. Arch. Biochem. Biophys. 411 (2003) 277–288. [PMID: 12623077]
[EC 2.1.1.315 created 2015]
 
 
EC 2.1.1.320     
Accepted name: type II protein arginine methyltransferase
Reaction: 2 S-adenosyl-L-methionine + [protein]-L-arginine = 2 S-adenosyl-L-homocysteine + [protein]-Nω,Nω′-dimethyl-L-arginine (overall reaction)
(1a) S-adenosyl-L-methionine + [protein]-L-arginine = S-adenosyl-L-homocysteine + [protein]-Nω-methyl-L-arginine
(1b) S-adenosyl-L-methionine + [protein]-Nω-methyl-L-arginine = S-adenosyl-L-homocysteine + [protein]-Nω,Nω′-dimethyl-L-arginine
Other name(s): PRMT5 (gene name); PRMT9 (gene name)
Systematic name: S-adenosyl-L-methionine:[protein]-L-arginine N-methyltransferase ([protein]-Nω,Nω′-dimethyl-L-arginine-forming)
Comments: The enzyme catalyses the methylation of one of the terminal guanidino nitrogen atoms in arginine residues within proteins, forming monomethylarginine, followed by the methylation of the second terminal nitrogen atom to form a symmetrical dimethylarginine. The mammalian enzyme is active in both the nucleus and the cytoplasm, and plays a role in the assembly of snRNP core particles by methylating certain small nuclear ribonucleoproteins. cf. EC 2.1.1.319, type I protein arginine methyltransferase, EC 2.1.1.321, type III protein arginine methyltransferase, and EC 2.1.1.322, type IV protein arginine methyltransferase.
References:
1.  Branscombe, T.L., Frankel, A., Lee, J.H., Cook, J.R., Yang, Z., Pestka, S. and Clarke, S. PRMT5 (Janus kinase-binding protein 1) catalyzes the formation of symmetric dimethylarginine residues in proteins. J. Biol. Chem. 276 (2001) 32971–32976. [PMID: 11413150]
2.  Wang, X., Zhang, Y., Ma, Q., Zhang, Z., Xue, Y., Bao, S. and Chong, K. SKB1-mediated symmetric dimethylation of histone H4R3 controls flowering time in Arabidopsis. EMBO J. 26 (2007) 1934–1941. [PMID: 17363895]
3.  Lacroix, M., El Messaoudi, S., Rodier, G., Le Cam, A., Sardet, C. and Fabbrizio, E. The histone-binding protein COPR5 is required for nuclear functions of the protein arginine methyltransferase PRMT5. EMBO Rep. 9 (2008) 452–458. [PMID: 18404153]
4.  Chari, A., Golas, M.M., Klingenhager, M., Neuenkirchen, N., Sander, B., Englbrecht, C., Sickmann, A., Stark, H. and Fischer, U. An assembly chaperone collaborates with the SMN complex to generate spliceosomal SnRNPs. Cell 135 (2008) 497–509. [PMID: 18984161]
5.  Antonysamy, S., Bonday, Z., Campbell, R.M., Doyle, B., Druzina, Z., Gheyi, T., Han, B., Jungheim, L.N., Qian, Y., Rauch, C., Russell, M., Sauder, J.M., Wasserman, S.R., Weichert, K., Willard, F.S., Zhang, A. and Emtage, S. Crystal structure of the human PRMT5:MEP50 complex. Proc. Natl. Acad. Sci. USA 109 (2012) 17960–17965. [PMID: 23071334]
6.  Hadjikyriacou, A., Yang, Y., Espejo, A., Bedford, M.T. and Clarke, S.G. Unique features of human protein arginine methyltransferase 9 (PRMT9) and its substrate RNA splicing factor SF3B2. J. Biol. Chem. 290 (2015) 16723–16743. [PMID: 25979344]
[EC 2.1.1.320 created 2015]
 
 
EC 2.1.1.329     
Accepted name: demethylphylloquinol methyltransferase
Reaction: S-adenosyl-L-methionine + demethylphylloquinol = S-adenosyl-L-homocysteine + phylloquinol
Glossary: demethylphylloquinol = 2-phytyl-1,4-naphthoquinol
phylloquinol = 2-methyl-3-phytyl-1,4-naphthoquinol = vitamin K1
Other name(s): menG (gene name); 2-phytyl-1,4-naphthoquinol methyltransferase
Systematic name: S-adenosyl-L-methionine:2-phytyl-1,4-naphthoquinol C-methyltransferase
Comments: The enzyme, found in plants and cyanobacteria, catalyses the final step in the biosynthesis of phylloquinone (vitamin K1), an electron carrier associated with photosystem I. The enzyme is specific for the quinol form of the substrate, and does not act on the quinone form [3].
References:
1.  Sakuragi, Y., Zybailov, B., Shen, G., Jones, A.D., Chitnis, P.R., van der Est, A., Bittl, R., Zech, S., Stehlik, D., Golbeck, J.H. and Bryant, D.A. Insertional inactivation of the menG gene, encoding 2-phytyl-1,4-naphthoquinone methyltransferase of Synechocystis sp. PCC 6803, results in the incorporation of 2-phytyl-1,4-naphthoquinone into the A1 site and alteration of the equilibrium constant between A1 and F(X) in photosystem I. Biochemistry 41 (2002) 394–405. [PMID: 11772039]
2.  Lohmann, A., Schottler, M.A., Brehelin, C., Kessler, F., Bock, R., Cahoon, E.B. and Dormann, P. Deficiency in phylloquinone (vitamin K1) methylation affects prenyl quinone distribution, photosystem I abundance, and anthocyanin accumulation in the Arabidopsis AtmenG mutant. J. Biol. Chem. 281 (2006) 40461–40472. [PMID: 17082184]
3.  Fatihi, A., Latimer, S., Schmollinger, S., Block, A., Dussault, P.H., Vermaas, W.F., Merchant, S.S. and Basset, G.J. A dedicated type II NADPH dehydrogenase performs the penultimate step in the biosynthesis of vitamin K1 in Synechocystis and Arabidopsis. Plant Cell 27 (2015) 1730–1741. [PMID: 26023160]
[EC 2.1.1.329 created 2016]
 
 
EC 2.1.1.345     
Accepted name: psilocybin synthase
Reaction: 2 S-adenosyl-L-methionine + 4-hydroxytryptamine 4-phosphate = 2 S-adenosyl-L-homocysteine + psilocybin (overall reaction)
(1a) S-adenosyl-L-methionine + 4-hydroxytryptamine 4-phosphate = S-adenosyl-L-homocysteine + 4-hydroxy-N-methyltryptamine 4-phosphate
(1b) S-adenosyl-L-methionine + 4-hydroxy-N-methyltryptamine 4-phosphate = S-adenosyl-L-homocysteine + psilocybin
Glossary: psilocybin = 3-[2-(dimethylamino)ethyl]-1H-indol-4-yl phosphate
Other name(s): PsiM
Systematic name: S-adenosyl-L-methionine:4-hydroxytryptamine-4-phosphate N,N-dimethyltransferase
Comments: Isolated from the fungus Psilocybe cubensis. The product, psilocybin, is a psychoactive compound.
References:
1.  Fricke, J., Blei, F. and Hoffmeister, D. Enzymatic synthesis of psilocybin. Angew. Chem. Int. Ed. Engl. 56 (2017) 12352–12355. [PMID: 28763571]
[EC 2.1.1.345 created 2017]
 
 
EC 2.1.1.368     
Accepted name: [histone H3]-lysine9 N-dimethyltransferase
Reaction: 2 S-adenosyl-L-methionine + a [histone H3]-L-lysine9 = 2 S-adenosyl-L-homocysteine + a [histone H3]-N6,N6-dimethyl-L-lysine9 (overall reaction)
(1a) S-adenosyl-L-methionine + a [histone H3]-L-lysine9 = S-adenosyl-L-homocysteine + a [histone H3]-N6-methyl-L-lysine9
(1b) S-adenosyl-L-methionine + a [histone H3]-N6-methyl-L-lysine9 = S-adenosyl-L-homocysteine + a [histone H3]-N6,N6-dimethyl-L-lysine9
Other name(s): SUVH1 (gene name); SUVR1 (gene name); SET32 (gene name); SDG32 (gene name); SET13 (gene name)
Systematic name: S-adenosyl-L-methionine:[histone H3]-L-lysine9 N6-dimethyltransferase
Comments: This entry describes several enzymes, characterized from plants, that successively methylate the L-lysine-9 residue of histone H3 (H3K9) twice, ultimately generating a dimethylated form. These modifications influence the binding of chromatin-associated proteins. In general, the methylation of H3K9 leads to transcriptional repression of the affected target genes. cf. EC 2.1.1.367, [histone H3]-lysine9 N-methyltransferase, EC 2.1.1.366, [histone H3]-N6,N6-dimethyl-lysine9 N-methyltransferase, and EC 2.1.1.355, [histone H3]-lysine9 N-trimethyltransferase.
References:
1.  Yu, Y., Dong, A. and Shen, W.H. Molecular characterization of the tobacco SET domain protein NtSET1 unravels its role in histone methylation, chromatin binding, and segregation. Plant J. 40 (2004) 699–711. [PMID: 15546353]
2.  Shen, W.H. and Meyer, D. Ectopic expression of the NtSET1 histone methyltransferase inhibits cell expansion, and affects cell division and differentiation in tobacco plants. Plant Cell Physiol. 45 (2004) 1715–1719. [PMID: 15574848]
3.  Naumann, K., Fischer, A., Hofmann, I., Krauss, V., Phalke, S., Irmler, K., Hause, G., Aurich, A.C., Dorn, R., Jenuwein, T. and Reuter, G. Pivotal role of AtSUVH2 in heterochromatic histone methylation and gene silencing in Arabidopsis. EMBO J. 24 (2005) 1418–1429. [PMID: 15775980]
[EC 2.1.1.368 created 2020]
 
 
EC 2.3.1.32     
Accepted name: lysine N-acetyltransferase
Reaction: acetyl phosphate + L-lysine = phosphate + N6-acetyl-L-lysine
Other name(s): lysine acetyltransferase; acetyl-phosphate:L-lysine 6-N-acetyltransferase
Systematic name: acetyl-phosphate:L-lysine N6-acetyltransferase
References:
1.  Paik, W.K. and Kim, S. Enzymic synthesis of ε-N-acetyl-L-lysine. Arch. Biochem. Biophys. 108 (1964) 221–229. [PMID: 14240571]
[EC 2.3.1.32 created 1972]
 
 
EC 2.3.1.48     
Accepted name: histone acetyltransferase
Reaction: acetyl-CoA + [protein]-L-lysine = CoA + [protein]-N6-acetyl-L-lysine
Other name(s): nucleosome-histone acetyltransferase; histone acetokinase; histone acetylase; histone transacetylase; lysine acetyltransferase; protein lysine acetyltransferase; acetyl-CoA:histone acetyltransferase
Systematic name: acetyl-CoA:[protein]-L-lysine acetyltransferase
Comments: A group of enzymes acetylating histones. Several of the enzymes can also acetylate lysines in other proteins [3,4].
References:
1.  Gallwitz, D. and Sures, I. Histone acetylation. Purification and properties of three histone-specific acetyltransferases from rat thymus nuclei. Biochim. Biophys. Acta 263 (1972) 315–328. [PMID: 5031160]
2.  Makowski, A.M., Dutnall, R.N. and Annunziato, A.T. Effects of acetylation of histone H4 at lysines 8 and 16 on activity of the Hat1 histone acetyltransferase. J. Biol. Chem. 276 (2001) 43499–43502. [PMID: 11585814]
3.  Lee, K.K. and Workman, J.L. Histone acetyltransferase complexes: one size doesn’t fit all. Nat. Rev. Mol. Cell. Biol. 8 (2007) 284–295. [PMID: 17380162]
4.  Thao, S. and Escalante-Semerena, J.C. Biochemical and thermodynamic analyses of Salmonella enterica Pat, a multidomain, multimeric Nε-lysine acetyltransferase involved in carbon and energy metabolism. MBio 2 (2011) E216. [PMID: 22010215]
5.  Wu, H., Moshkina, N., Min, J., Zeng, H., Joshua, J., Zhou, M.M. and Plotnikov, A.N. Structural basis for substrate specificity and catalysis of human histone acetyltransferase 1. Proc. Natl. Acad. Sci. USA 109 (2012) 8925–8930. [PMID: 22615379]
6.  Das, C., Roy, S., Namjoshi, S., Malarkey, C.S., Jones, D.N., Kutateladze, T.G., Churchill, M.E. and Tyler, J.K. Binding of the histone chaperone ASF1 to the CBP bromodomain promotes histone acetylation. Proc. Natl. Acad. Sci. USA 111 (2014) E1072–E1081. [PMID: 24616510]
[EC 2.3.1.48 created 1976, modified 2017]
 
 
EC 2.3.1.102     
Accepted name: N6-hydroxylysine N-acetyltransferase
Reaction: acetyl-CoA + N6-hydroxy-L-lysine = CoA + N6-acetyl-N6-hydroxy-L-lysine
Other name(s): N6-hydroxylysine:acetyl CoA N6-transacetylase; N6-hydroxylysine acetylase; acetyl-CoA:6-N-hydroxy-L-lysine 6-acetyltransferase; N6-hydroxylysine O-acetyltransferase (incorrect)
Systematic name: acetyl-CoA:N6-hydroxy-L-lysine 6-acetyltransferase
Comments: Involved in the synthesis of aerobactin from lysine in a strain of Escherichia coli.
References:
1.  Coy, M., Paw, B.H., Bindereif, A. and Neilands, J.B. Isolation and properties of Nε-hydroxylysine:acetyl coenzyme A Nε-transacetylase from Escherichia coli pABN11. Biochemistry 25 (1986) 2485–2489. [PMID: 3521734]
2.  de Lorenzo, V., Bindereif, A., Paw, B.H. and Neilands, J.B. Aerobactin biosynthesis and transport genes of plasmid ColV-K30 in Escherichia coli K-12. J. Bacteriol. 165 (1986) 570–578. [PMID: 2935523]
[EC 2.3.1.102 created 1989]
 
 
EC 2.3.1.103     
Accepted name: sinapoylglucose—sinapoylglucose O-sinapoyltransferase
Reaction: 2 1-O-sinapoyl-β-D-glucose = D-glucose + 1,2-bis-O-sinapoyl-β-D-glucose
Glossary: 1-O-sinapoyl-β-D-glucose = 1-O-[(2E)-3-(4-hydroxy-3,5-dimethoxyphenyl)-2-propenoyl]-β-D-glucopyranose
Other name(s): hydroxycinnamoylglucose-hydroxycinnamoylglucose hydroxycinnamoyltransferase; 1-(hydroxycinnamoyl)-glucose:1-(hydroxycinnamoyl)-glucose hydroxycinnamoyltransferase; 1-O-(4-hydroxy-3,5-dimethoxycinnamoyl)-β-D-glucoside:1-O-(4-hydroxy-3,5-dimethoxycinnamoyl)-β-D-glucoside 1-O-sinapoyltransferase
Systematic name: 1-O-sinapoyl-β-D-glucose:1-O-sinnapoyl-β-D-glucose 1-O-sinapoyltransferase
Comments: The plant enzyme, characterized from Brassicaceae, is involved in secondary metabolism.
References:
1.  Dahlbender, B. and Strack, D. Purification and properties of 1-(hydroxycinnamoyl)-glucose-1-(hydroxycinnamoyl)-glucose hydroxycinnamoyl-transferase from radish seedlings. Phytochemistry 25 (1986) 1043–1046.
2.  Fraser, C.M., Thompson, M.G., Shirley, A.M., Ralph, J., Schoenherr, J.A., Sinlapadech, T., Hall, M.C. and Chapple, C. Related Arabidopsis serine carboxypeptidase-like sinapoylglucose acyltransferases display distinct but overlapping substrate specificities. Plant Physiol. 144 (2007) 1986–1999. [PMID: 17600138]
[EC 2.3.1.103 created 1989]
 
 
EC 2.3.1.152     
Accepted name: alcohol O-cinnamoyltransferase
Reaction: 1-O-trans-cinnamoyl-β-D-glucopyranose + ROH = alkyl cinnamate + glucose
Systematic name: 1-O-trans-cinnamoyl-β-D-glucopyranose:alcohol O-cinnamoyltransferase
Comments: Acceptor alcohols (ROH) include methanol, ethanol and propanol. No cofactors are required as 1-O-trans-cinnamoyl-β-D-glucopyranose itself is an "energy-rich" (activated) acyl-donor, comparable to CoA-thioesters. 1-O-trans-Cinnamoyl-β-D-gentobiose can also act as the acyl donor, but with much less affinity.
References:
1.  Mock, H.-P., Strack, D. Energetics of uridine 5′-diphosphoglucose-hydroxy-cinnamic acid acyl-glucotransferase reaction. Phytochemistry 32 (1993) 575–579.
2.  Latza, S., Gansser, D., Berger, R.G. Carbohydrate esters of cinnamic acid from fruits of Physalis peruviana, Psidium guajava and Vaccinium vitis IDAEA. Phytochemistry 43 (1996) 481–485.
[EC 2.3.1.152 created 1999]
 
 
EC 2.3.1.181     
Accepted name: lipoyl(octanoyl) transferase
Reaction: an octanoyl-[acyl-carrier protein] + a protein = a protein N6-(octanoyl)lysine + an [acyl-carrier protein]
Glossary: lipoyl group
Other name(s): LipB; lipoyl (octanoyl)-[acyl-carrier-protein]-protein N-lipoyltransferase; lipoyl (octanoyl)-acyl carrier protein:protein transferase; lipoate/octanoate transferase; lipoyltransferase; octanoyl-[acyl carrier protein]-protein N-octanoyltransferase; lipoyl(octanoyl)transferase; octanoyl-[acyl-carrier-protein]:protein N-octanoyltransferase
Systematic name: octanoyl-[acyl-carrier protein]:protein N-octanoyltransferase
Comments: This is the first committed step in the biosynthesis of lipoyl cofactor. Lipoylation is essential for the function of several key enzymes involved in oxidative metabolism, as it converts apoprotein into the biologically active holoprotein. Examples of such lipoylated proteins include pyruvate dehydrogenase (E2 domain), 2-oxoglutarate dehydrogenase (E2 domain), the branched-chain 2-oxoacid dehydrogenases and the glycine cleavage system (H protein) [2,3]. Lipoyl-ACP can also act as a substrate [4] although octanoyl-ACP is likely to be the true substrate [6]. The other enzyme involved in the biosynthesis of lipoyl cofactor is EC 2.8.1.8, lipoyl synthase. An alternative lipoylation pathway involves EC 6.3.1.20, lipoate—protein ligase, which can lipoylate apoproteins using exogenous lipoic acid (or its analogues).
References:
1.  Nesbitt, N.M., Baleanu-Gogonea, C., Cicchillo, R.M., Goodson, K., Iwig, D.F., Broadwater, J.A., Haas, J.A., Fox, B.G. and Booker, S.J. Expression, purification, and physical characterization of Escherichia coli lipoyl(octanoyl)transferase. Protein Expr. Purif. 39 (2005) 269–282. [PMID: 15642479]
2.  Vanden Boom, T.J., Reed, K.E. and Cronan, J.E., Jr. Lipoic acid metabolism in Escherichia coli: isolation of null mutants defective in lipoic acid biosynthesis, molecular cloning and characterization of the E. coli lip locus, and identification of the lipoylated protein of the glycine cleavage system. J. Bacteriol. 173 (1991) 6411–6420. [PMID: 1655709]
3.  Jordan, S.W. and Cronan, J.E., Jr. A new metabolic link. The acyl carrier protein of lipid synthesis donates lipoic acid to the pyruvate dehydrogenase complex in Escherichia coli and mitochondria. J. Biol. Chem. 272 (1997) 17903–17906. [PMID: 9218413]
4.  Zhao, X., Miller, J.R., Jiang, Y., Marletta, M.A. and Cronan, J.E. Assembly of the covalent linkage between lipoic acid and its cognate enzymes. Chem. Biol. 10 (2003) 1293–1302. [PMID: 14700636]
5.  Wada, M., Yasuno, R., Jordan, S.W., Cronan, J.E., Jr. and Wada, H. Lipoic acid metabolism in Arabidopsis thaliana: cloning and characterization of a cDNA encoding lipoyltransferase. Plant Cell Physiol. 42 (2001) 650–656. [PMID: 11427685]
6.  Perham, R.N. Swinging arms and swinging domains in multifunctional enzymes: catalytic machines for multistep reactions. Annu. Rev. Biochem. 69 (2000) 961–1004. [PMID: 10966480]
[EC 2.3.1.181 created 2006, modified 2016]
 
 
EC 2.3.1.195     
Accepted name: (Z)-3-hexen-1-ol acetyltransferase
Reaction: acetyl-CoA + (3Z)-hex-3-en-1-ol = CoA + (3Z)-hex-3-en-1-yl acetate
Other name(s): CHAT; At3g03480
Systematic name: acetyl-CoA:(3Z)-hex-3-en-1-ol acetyltransferase
Comments: The enzyme is resonsible for the production of (3Z)-hex-3-en-1-yl acetate, the major volatile compound released upon mechanical wounding of the leaves of Arabidopsis thaliana [1].
References:
1.  D'Auria, J.C., Pichersky, E., Schaub, A., Hansel, A. and Gershenzon, J. Characterization of a BAHD acyltransferase responsible for producing the green leaf volatile (Z)-3-hexen-1-yl acetate in Arabidopsis thaliana. Plant J. 49 (2007) 194–207. [PMID: 17163881]
2.  D'Auria, J.C., Chen, F. and Pichersky, E. Characterization of an acyltransferase capable of synthesizing benzylbenzoate and other volatile esters in flowers and damaged leaves of Clarkia breweri. Plant Physiol. 130 (2002) 466–476. [PMID: 12226525]
[EC 2.3.1.195 created 2011]
 
 
EC 2.3.1.199     
Accepted name: very-long-chain 3-oxoacyl-CoA synthase
Reaction: a very-long-chain acyl-CoA + malonyl-CoA = a very-long-chain 3-oxoacyl-CoA + CO2 + CoA
Glossary: a very-long-chain acyl-CoA = an acyl-CoA thioester where the acyl chain contains 23 or more carbon atoms.
Other name(s): very-long-chain 3-ketoacyl-CoA synthase; very-long-chain β-ketoacyl-CoA synthase; condensing enzyme (ambiguous); CUT1 (gene name); CER6 (gene name); FAE1 (gene name); KCS (gene name); ELO (gene name)
Systematic name: malonyl-CoA:very-long-chain acyl-CoA malonyltransferase (decarboxylating and thioester-hydrolysing)
Comments: This is the first component of the elongase, a microsomal protein complex responsible for extending palmitoyl-CoA and stearoyl-CoA (and modified forms thereof) to very-long-chain acyl CoAs. Multiple forms exist with differing preferences for the substrate, and thus the specific form expressed determines the local composition of very-long-chain fatty acids [6,7]. For example, the FAE1 form from the plant Arabidopsis thaliana accepts only 16 and 18 carbon substrates, with oleoyl-CoA (18:1) being the preferred substrate [5], while CER6 from the same plant prefers substrates with chain length of C22 to C32 [4,8]. cf. EC 1.1.1.330, very-long-chain 3-oxoacyl-CoA reductase, EC 4.2.1.134, very-long-chain (3R)-3-hydroxyacyl-[acyl-carrier protein] dehydratase, and EC 1.3.1.93, very-long-chain enoyl-CoA reductase
References:
1.  Toke, D.A. and Martin, C.E. Isolation and characterization of a gene affecting fatty acid elongation in Saccharomyces cerevisiae. J. Biol. Chem. 271 (1996) 18413–18422. [PMID: 8702485]
2.  Oh, C.S., Toke, D.A., Mandala, S. and Martin, C.E. ELO2 and ELO3, homologues of the Saccharomyces cerevisiae ELO1 gene, function in fatty acid elongation and are required for sphingolipid formation. J. Biol. Chem. 272 (1997) 17376–17384. [PMID: 9211877]
3.  Dittrich, F., Zajonc, D., Huhne, K., Hoja, U., Ekici, A., Greiner, E., Klein, H., Hofmann, J., Bessoule, J.J., Sperling, P. and Schweizer, E. Fatty acid elongation in yeast--biochemical characteristics of the enzyme system and isolation of elongation-defective mutants. Eur. J. Biochem. 252 (1998) 477–485. [PMID: 9546663]
4.  Millar, A.A., Clemens, S., Zachgo, S., Giblin, E.M., Taylor, D.C. and Kunst, L. CUT1, an Arabidopsis gene required for cuticular wax biosynthesis and pollen fertility, encodes a very-long-chain fatty acid condensing enzyme. Plant Cell 11 (1999) 825–838. [PMID: 10330468]
5.  Ghanevati, M. and Jaworski, J.G. Engineering and mechanistic studies of the Arabidopsis FAE1 β-ketoacyl-CoA synthase, FAE1 KCS. Eur. J. Biochem. 269 (2002) 3531–3539. [PMID: 12135493]
6.  Blacklock, B.J. and Jaworski, J.G. Substrate specificity of Arabidopsis 3-ketoacyl-CoA synthases. Biochem. Biophys. Res. Commun. 346 (2006) 583–590. [PMID: 16765910]
7.  Denic, V. and Weissman, J.S. A molecular caliper mechanism for determining very long-chain fatty acid length. Cell 130 (2007) 663–677. [PMID: 17719544]
8.  Tresch, S., Heilmann, M., Christiansen, N., Looser, R. and Grossmann, K. Inhibition of saturated very-long-chain fatty acid biosynthesis by mefluidide and perfluidone, selective inhibitors of 3-ketoacyl-CoA synthases. Phytochemistry 76 (2012) 162–171. [PMID: 22284369]
[EC 2.3.1.199 created 2012]
 
 
EC 2.3.1.225     
Accepted name: protein S-acyltransferase
Reaction: palmitoyl-CoA + [protein]-L-cysteine = [protein]-S-palmitoyl-L-cysteine + CoA
Other name(s): DHHC palmitoyl transferase; S-protein acyltransferase; G-protein palmitoyltransferase
Systematic name: palmitoyl-CoA:[protein]-L-cysteine S-palmitoyltransferase
Comments: The enzyme catalyses the posttranslational protein palmitoylation that plays a role in protein-membrane interactions, protein trafficking, and enzyme activity. Palmitoylation increases the hydrophobicity of proteins or protein domains and contributes to their membrane association.
References:
1.  Dunphy, J.T., Greentree, W.K., Manahan, C.L. and Linder, M.E. G-protein palmitoyltransferase activity is enriched in plasma membranes. J. Biol. Chem. 271 (1996) 7154–7159. [PMID: 8636152]
2.  Veit, M., Dietrich, L.E. and Ungermann, C. Biochemical characterization of the vacuolar palmitoyl acyltransferase. FEBS Lett. 540 (2003) 101–105. [PMID: 12681491]
3.  Batistic, O. Genomics and localization of the Arabidopsis DHHC-cysteine-rich domain S-acyltransferase protein family. Plant Physiol. 160 (2012) 1597–1612. [PMID: 22968831]
4.  Jennings, B.C. and Linder, M.E. DHHC protein S-acyltransferases use similar ping-pong kinetic mechanisms but display different acyl-CoA specificities. J. Biol. Chem. 287 (2012) 7236–7245. [PMID: 22247542]
5.  Zhou, L.Z., Li, S., Feng, Q.N., Zhang, Y.L., Zhao, X., Zeng, Y.L., Wang, H., Jiang, L. and Zhang, Y. Protein S-acyl transferase10 is critical for development and salt tolerance in Arabidopsis. Plant Cell 25 (2013) 1093–1107. [PMID: 23482856]
[EC 2.3.1.225 created 2013]
 
 
EC 2.3.1.246     
Accepted name: 3,5-dihydroxyphenylacetyl-CoA synthase
Reaction: 4 malonyl-CoA = (3,5-dihydroxyphenylacetyl)-CoA + 3 CoA + 4 CO2 + H2O
Other name(s): DpgA
Systematic name: malonyl-CoA:malonyl-CoA malonyltransferase (3,5-dihydroxyphenylacetyl-CoA-forming)
Comments: The enzyme, characterized from the bacterium Amycolatopsis mediterranei, is involved in biosynthesis of the nonproteinogenic amino acid (S)-3,5-dihydroxyphenylglycine, a component of the vancomycin-type antibiotic balhimycin.
References:
1.  Pfeifer, V., Nicholson, G.J., Ries, J., Recktenwald, J., Schefer, A.B., Shawky, R.M., Schroder, J., Wohlleben, W. and Pelzer, S. A polyketide synthase in glycopeptide biosynthesis: the biosynthesis of the non-proteinogenic amino acid (S)-3,5-dihydroxyphenylglycine. J. Biol. Chem. 276 (2001) 38370–38377. [PMID: 11495926]
2.  Chen, H., Tseng, C.C., Hubbard, B.K. and Walsh, C.T. Glycopeptide antibiotic biosynthesis: enzymatic assembly of the dedicated amino acid monomer (S)-3,5-dihydroxyphenylglycine. Proc. Natl. Acad. Sci. USA 98 (2001) 14901–14906. [PMID: 11752437]
3.  Tseng, C.C., McLoughlin, S.M., Kelleher, N.L. and Walsh, C.T. Role of the active site cysteine of DpgA, a bacterial type III polyketide synthase. Biochemistry 43 (2004) 970–980. [PMID: 14744141]
4.  Wu, H.C., Li, Y.S., Liu, Y.C., Lyu, S.Y., Wu, C.J. and Li, T.L. Chain elongation and cyclization in type III PKS DpgA. ChemBioChem 13 (2012) 862–871. [PMID: 22492619]
[EC 2.3.1.246 created 2015]
 
 
EC 2.3.1.248     
Accepted name: spermidine disinapoyl transferase
Reaction: 2 sinapoyl-CoA + spermidine = 2 CoA + N1,N8-bis(sinapoyl)-spermidine
Other name(s): SDT
Systematic name: sinapoyl-CoA:spermidine N-(hydroxycinnamoyl)transferase
Comments: The enzyme from the plant Arabidopsis thaliana has no activity with 4-coumaroyl-CoA (cf. EC 2.3.1.249, spermidine dicoumaroyl transferase).
References:
1.  Luo, J., Fuell, C., Parr, A., Hill, L., Bailey, P., Elliott, K., Fairhurst, S.A., Martin, C. and Michael, A.J. A novel polyamine acyltransferase responsible for the accumulation of spermidine conjugates in Arabidopsis seed. Plant Cell 21 (2009) 318–333. [PMID: 19168716]
[EC 2.3.1.248 created 2015]
 
 
EC 2.3.1.249     
Accepted name: spermidine dicoumaroyl transferase
Reaction: 2 4-coumaroyl-CoA + spermidine = 2 CoA + N1,N8-bis(4-coumaroyl)-spermidine
Other name(s): SCT
Systematic name: 4-coumaroyl-CoA:spermidine N-(hydroxycinnamoyl)transferase
Comments: The enzyme from the plant Arabidopsis thaliana has no activity with sinapoyl-CoA (cf. EC 2.3.1.248, spermidine disinapoyl transferase).
References:
1.  Luo, J., Fuell, C., Parr, A., Hill, L., Bailey, P., Elliott, K., Fairhurst, S.A., Martin, C. and Michael, A.J. A novel polyamine acyltransferase responsible for the accumulation of spermidine conjugates in Arabidopsis seed. Plant Cell 21 (2009) 318–333. [PMID: 19168716]
[EC 2.3.1.249 created 2015]
 
 
EC 2.3.1.254     
Accepted name: N-terminal methionine Nα-acetyltransferase NatB
Reaction: (1) acetyl-CoA + an N-terminal L-methionyl-L-asparaginyl-[protein] = an N-terminal Nα-acetyl-L-methionyl-L-asparaginyl-[protein] + CoA
(2) acetyl-CoA + an N-terminal L-methionyl-L-glutaminyl-[protein] = an N-terminal Nα-acetyl-L-methionyl-L-glutaminyl-[protein] + CoA
(3) acetyl-CoA + an N-terminal L-methionyl-L-aspartyl-[protein] = an N-terminal Nα-acetyl-L-methionyl-L-aspartyl-[protein] + CoA
(4) acetyl-CoA + an N-terminal L-methionyl-L-glutamyl-[protein] = an N-terminal Nα-acetyl-L-methionyl-L-glutamyl-[protein] + CoA
Other name(s): NAA20 (gene name); NAA25 (gene name)
Systematic name: acetyl-CoA:N-terminal Met-Asn/Gln/Asp/Glu-[protein] Met-Nα-acetyltransferase
Comments: N-terminal acetylases (NATs) catalyse the covalent attachment of an acetyl moiety from acetyl-CoA to the free α-amino group at the N-terminus of a protein. This irreversible modification neutralizes the positive charge at the N-terminus and makes the N-terminal residue larger and more hydrophobic, and may also play a role in membrane targeting and gene silencing. The NatB complex is found in all eukaryotic organisms, and specifically targets N-terminal L-methionine residues attached to Asn, Asp, Gln, or Glu residues at the second position.
References:
1.  Starheim, K.K., Arnesen, T., Gromyko, D., Ryningen, A., Varhaug, J.E. and Lillehaug, J.R. Identification of the human Nα-acetyltransferase complex B (hNatB): a complex important for cell-cycle progression. Biochem. J. 415 (2008) 325–331. [PMID: 18570629]
2.  Ferrandez-Ayela, A., Micol-Ponce, R., Sanchez-Garcia, A.B., Alonso-Peral, M.M., Micol, J.L. and Ponce, M.R. Mutation of an Arabidopsis NatB N-α-terminal acetylation complex component causes pleiotropic developmental defects. PLoS One 8:e80697 (2013). [PMID: 24244708]
3.  Lee, K.E., Ahn, J.Y., Kim, J.M. and Hwang, C.S. Synthetic lethal screen of NAA20, a catalytic subunit gene of NatB N-terminal acetylase in Saccharomyces cerevisiae. J Microbiol 52 (2014) 842–848. [PMID: 25163837]
[EC 2.3.1.254 created 1989 as EC 2.3.1.88, part transferred 2016 to EC 2.3.1.254]
 
 
EC 2.3.1.255     
Accepted name: N-terminal amino-acid Nα-acetyltransferase NatA
Reaction: (1) acetyl-CoA + an N-terminal-glycyl-[protein] = an N-terminal-Nα-acetyl-glycyl-[protein] + CoA
(2) acetyl-CoA + an N-terminal-L-alanyl-[protein] = an N-terminal-Nα-acetyl-L-alanyl-[protein] + CoA
(3) acetyl-CoA + an N-terminal-L-seryl-[protein] = an N-terminal-Nα-acetyl-L-seryl-[protein] + CoA
(4) acetyl-CoA + an N-terminal-L-valyl-[protein] = an N-terminal-Nα-acetyl-L-valyl-[protein] + CoA
(5) acetyl-CoA + an N-terminal-L-cysteinyl-[protein] = an N-terminal-Nα-acetyl-L-cysteinyl-[protein] + CoA
(6) acetyl-CoA + an N-terminal-L-threonyl-[protein] = an N-terminal-Nα-acetyl-L-threonyl-[protein] + CoA
Other name(s): NAA10 (gene name); NAA15 (gene name); ARD1 (gene name)
Systematic name: acetyl-CoA:N-terminal-Gly/Ala/Ser/Val/Cys/Thr-[protein] Nα-acetyltransferase
Comments: N-terminal-acetylases (NATs) catalyse the covalent attachment of an acetyl moiety from acetyl-CoA to the free α-amino group at the N-terminus of a protein. This irreversible modification neutralizes the positive charge at the N-terminus and makes the N-terminal residue larger and more hydrophobic. The NatA complex is found in all eukaryotic organisms, and specifically targets N-terminal Ala, Gly, Cys, Ser, Thr, and Val residues, that became available after removal of the initiator methionine.
References:
1.  Mullen, J.R., Kayne, P.S., Moerschell, R.P., Tsunasawa, S., Gribskov, M., Colavito-Shepanski, M., Grunstein, M., Sherman, F. and Sternglanz, R. Identification and characterization of genes and mutants for an N-terminal acetyltransferase from yeast. EMBO J. 8 (1989) 2067–2075. [PMID: 2551674]
2.  Park, E.C. and Szostak, J.W. ARD1 and NAT1 proteins form a complex that has N-terminal acetyltransferase activity. EMBO J. 11 (1992) 2087–2093. [PMID: 1600941]
3.  Sugiura, N., Adams, S.M. and Corriveau, R.A. An evolutionarily conserved N-terminal acetyltransferase complex associated with neuronal development. J. Biol. Chem. 278 (2003) 40113–40120. [PMID: 12888564]
4.  Gautschi, M., Just, S., Mun, A., Ross, S., Rucknagel, P., Dubaquie, Y., Ehrenhofer-Murray, A. and Rospert, S. The yeast Nα-acetyltransferase NatA is quantitatively anchored to the ribosome and interacts with nascent polypeptides. Mol. Cell Biol. 23 (2003) 7403–7414. [PMID: 14517307]
5.  Xu, F., Huang, Y., Li, L., Gannon, P., Linster, E., Huber, M., Kapos, P., Bienvenut, W., Polevoda, B., Meinnel, T., Hell, R., Giglione, C., Zhang, Y., Wirtz, M., Chen, S. and Li, X. Two N-terminal acetyltransferases antagonistically regulate the stability of a nod-like receptor in Arabidopsis. Plant Cell 27 (2015) 1547–1562. [PMID: 25966763]
6.  Dorfel, M.J. and Lyon, G.J. The biological functions of Naa10 - From amino-terminal acetylation to human disease. Gene 567 (2015) 103–131. [PMID: 25987439]
[EC 2.3.1.255 created 1989 as EC 2.3.1.88, part transferred 2016 to EC 2.3.1.255]
 
 
EC 2.3.1.256     
Accepted name: N-terminal methionine Nα-acetyltransferase NatC
Reaction: (1) acetyl-CoA + an N-terminal-L-methionyl-L-leucyl-[protein] = an N-terminal-Nα-acetyl-L-methionyl-L-leucyl-[protein] + CoA
(2) acetyl-CoA + an N-terminal-L-methionyl-L-isoleucyl-[protein] = an N-terminal-Nα-acetyl-L-methionyl-L-isoleucyl-[protein] + CoA
(3) acetyl-CoA + an N-terminal-L-methionyl-L-phenylalanyl-[protein] = an N-terminal-Nα-acetyl-L-methionyl-L-phenylalanyl-[protein] + CoA
(4) acetyl-CoA + an N-terminal-L-methionyl-L-tryptophyl-[protein] = an N-terminal-Nα-acetyl-L-methionyl-L-tryptophyl-[protein] + CoA
(5) acetyl-CoA + an N-terminal-L-methionyl-L-tyrosyl-[protein] = an N-terminal-Nα-acetyl-L-methionyl-L-tyrosyl-[protein] + CoA
Other name(s): NAA30 (gene name); NAA35 (gene name); NAA38 (gene name); MAK3 (gene name); MAK10 (gene name); MAK31 (gene name)
Systematic name: acetyl-CoA:N-terminal-Met-Leu/Ile/Phe/Trp/Tyr-[protein] Met Nα-acetyltransferase
Comments: N-terminal-acetylases (NATs) catalyse the covalent attachment of an acetyl moiety from acetyl-CoA to the free α-amino group at the N-terminus of a protein. This irreversible modification neutralizes the positive charge at the N-terminus and makes the N-terminal residue larger and more hydrophobic, and may also play a role in membrane targeting and gene silencing. The NatC complex is found in all eukaryotic organisms, and specifically targets N-terminal L-methionine residues attached to bulky hydrophobic residues at the second position, including Leu, Ile, Phe, Trp, and Tyr residues.
References:
1.  Polevoda, B. and Sherman, F. NatC Nα-terminal acetyltransferase of yeast contains three subunits, Mak3p, Mak10p, and Mak31p. J. Biol. Chem. 276 (2001) 20154–20159. [PMID: 11274203]
2.  Polevoda, B. and Sherman, F. Composition and function of the eukaryotic N-terminal acetyltransferase subunits. Biochem. Biophys. Res. Commun. 308 (2003) 1–11. [PMID: 12890471]
3.  Pesaresi, P., Gardner, N.A., Masiero, S., Dietzmann, A., Eichacker, L., Wickner, R., Salamini, F. and Leister, D. Cytoplasmic N-terminal protein acetylation is required for efficient photosynthesis in Arabidopsis. Plant Cell 15 (2003) 1817–1832. [PMID: 12897255]
4.  Wenzlau, J.M., Garl, P.J., Simpson, P., Stenmark, K.R., West, J., Artinger, K.B., Nemenoff, R.A. and Weiser-Evans, M.C. Embryonic growth-associated protein is one subunit of a novel N-terminal acetyltransferase complex essential for embryonic vascular development. Circ. Res. 98 (2006) 846–855. [PMID: 16484612]
5.  Starheim, K.K., Gromyko, D., Evjenth, R., Ryningen, A., Varhaug, J.E., Lillehaug, J.R. and Arnesen, T. Knockdown of human Nα-terminal acetyltransferase complex C leads to p53-dependent apoptosis and aberrant human Arl8b localization. Mol. Cell Biol. 29 (2009) 3569–3581. [PMID: 19398576]
[EC 2.3.1.256 created 1989 as EC 2.3.1.88, part transferred 2016 to EC 2.3.1.256]
 
 
EC 2.3.1.258     
Accepted name: N-terminal methionine Nα-acetyltransferase NatE
Reaction: (1) acetyl-CoA + an N-terminal-L-methionyl-L-alanyl-[protein] = an N-terminal-Nα-acetyl-L-methionyl-L-alanyl-[protein] + CoA
(2) acetyl-CoA + an N-terminal-L-methionyl-L-seryl-[protein] = an N-terminal-Nα-acetyl-L-methionyl-L-seryl-[protein] + CoA
(3) acetyl-CoA + an N-terminal-L-methionyl-L-valyl-[protein] = an N-terminal-Nα-acetyl-L-methionyl-L-valyl-[protein] + CoA
(4) acetyl-CoA + an N-terminal-L-methionyl-L-threonyl-[protein] = an N-terminal-Nα-acetyl-L-methionyl-L-threonyl-[protein] + CoA
(5) acetyl-CoA + an N-terminal-L-methionyl-L-lysyl-[protein] = an N-terminal-Nα-acetyl-L-methionyl-L-lysyl-[protein] + CoA
(6) acetyl-CoA + an N-terminal-L-methionyl-L-leucyl-[protein] = an N-terminal-Nα-acetyl-L-methionyl-L-leucyl-[protein] + CoA
(7) acetyl-CoA + an N-terminal-L-methionyl-L-phenylalanyl-[protein] = an N-terminal-Nα-acetyl-L-methionyl-L-phenylalanyl-[protein] + CoA
(8) acetyl-CoA + an N-terminal-L-methionyl-L-tyrosyl-[protein] = an N-terminal-Nα-acetyl-L-methionyl-L-tyrosyl-[protein] + CoA
Other name(s): NAA50 (gene name); NAT5; SAN
Systematic name: acetyl-CoA:N-terminal-Met-Ala/Ser/Val/Thr/Lys/Leu/Phe/Tyr-[protein] Met-Nα-acetyltransferase
Comments: N-terminal-acetylases (NATs) catalyse the covalent attachment of an acetyl moiety from acetyl-CoA to the free α-amino group at the N-terminus of a protein. This irreversible modification neutralizes the positive charge at the N-terminus, makes the N-terminal residue larger and more hydrophobic, and prevents its removal by hydrolysis. It may also play a role in membrane targeting and gene silencing. NatE is found in all eukaryotic organisms and plays an important role in chromosome resolution and segregation. It specifically targets N-terminal L-methionine residues attached to Lys, Val, Ala, Tyr, Phe, Leu, Ser, and Thr. There is some substrate overlap with EC 2.3.1.256, N-terminal methionine Nα-acetyltransferase NatC. In addition, the acetylation of Met followed by small residues such as Ser, Thr, Ala, or Val suggests a kinetic competition between NatE and EC 3.4.11.18, methionyl aminopeptidase. The enzyme also has the activity of EC 2.3.1.48, histone acetyltransferase, and autoacetylates several of its own lysine residues.
References:
1.  Hou, F., Chu, C.W., Kong, X., Yokomori, K. and Zou, H. The acetyltransferase activity of San stabilizes the mitotic cohesin at the centromeres in a shugoshin-independent manner. J. Cell Biol. 177 (2007) 587–597. [PMID: 17502424]
2.  Pimenta-Marques, A., Tostoes, R., Marty, T., Barbosa, V., Lehmann, R. and Martinho, R.G. Differential requirements of a mitotic acetyltransferase in somatic and germ line cells. Dev. Biol. 323 (2008) 197–206. [PMID: 18801358]
3.  Evjenth, R., Hole, K., Karlsen, O.A., Ziegler, M., Arnesen, T. and Lillehaug, J.R. Human Naa50p (Nat5/San) displays both protein Nα- and Nε-acetyltransferase activity. J. Biol. Chem. 284 (2009) 31122–31129. [PMID: 19744929]
4.  Van Damme, P., Hole, K., Gevaert, K. and Arnesen, T. N-terminal acetylome analysis reveals the specificity of Naa50 (Nat5) and suggests a kinetic competition between N-terminal acetyltransferases and methionine aminopeptidases. Proteomics 15 (2015) 2436–2446. [PMID: 25886145]
[EC 2.3.1.258 created 1989 as EC 2.3.1.88, part transferred 2016 to EC 2.3.1.258]
 
 
EC 2.3.1.264     
Accepted name: β-lysine N6-acetyltransferase
Reaction: acetyl-CoA + (3S)-3,6-diaminohexanoate = CoA + (3S)-6-acetamido-3-aminohexanoate
Glossary: (3S)-3,6-diaminohexanoate = β-L-lysine
(3S)-6-acetamido-3-aminohexanoate = N6-acetyl-β-L-lysine
Other name(s): ablB (gene name)
Systematic name: acetyl-CoA:(3S)-3,6-diaminohexanoate N6-acetyltransferase
Comments: The enzyme is found in some methanogenic archaea and bacteria. In archaea it is induced under salt stress. The product, N6-acetyl-β-L-lysine, serves as a compatible solute, conferring high salt resistance on the producing organisms.
References:
1.  Pfluger, K., Baumann, S., Gottschalk, G., Lin, W., Santos, H. and Muller, V. Lysine-2,3-aminomutase and β-lysine acetyltransferase genes of methanogenic archaea are salt induced and are essential for the biosynthesis of Nε-acetyl-β-lysine and growth at high salinity. Appl. Environ. Microbiol. 69 (2003) 6047–6055. [PMID: 14532061]
2.  Muller, S., Hoffmann, T., Santos, H., Saum, S.H., Bremer, E. and Muller, V. Bacterial abl-like genes: production of the archaeal osmolyte N(ε)-acetyl-β-lysine by homologous overexpression of the yodP-kamA genes in Bacillus subtilis. Appl. Microbiol. Biotechnol. 91 (2011) 689–697. [PMID: 21538109]
[EC 2.3.1.264 created 2017]
 
 
EC 2.3.2.13     
Accepted name: protein-glutamine γ-glutamyltransferase
Reaction: protein glutamine + alkylamine = protein N5-alkylglutamine + NH3
Other name(s): transglutaminase; Factor XIIIa; fibrinoligase; fibrin stabilizing factor; glutaminylpeptide γ-glutamyltransferase; polyamine transglutaminase; tissue transglutaminase; R-glutaminyl-peptide:amine γ-glutamyl transferase
Systematic name: protein-glutamine:amine γ-glutamyltransferase
Comments: Requires Ca2+. The γ-carboxamide groups of peptide-bound glutamine residues act as acyl donors, and the 6-amino-groups of protein- and peptide-bound lysine residues act as acceptors, to give intra- and inter-molecular N6-(5-glutamyl)-lysine crosslinks. Formed by proteolytic cleavage from plasma Factor XIII
References:
1.  Folk, J.E. and Chung, S.I. Molecular and catalytic properties of transglutaminases. Adv. Enzymol. Relat. Areas Mol. Biol. 38 (1973) 109–191. [PMID: 4151471]
2.  Folk, J.E. and Cole, P.W. Mechanism of action of guinea pig liver transglutaminase. I. Purification and properties of the enzyme: identification of a functional cysteine essential for activity. J. Biol. Chem. 241 (1966) 5518–5525. [PMID: 5928192]
3.  Folk, J.E. and Finlayson, J.S. The ε-(γ-glutamyl)lysine crosslink and the catalytic role of transglutaminases. Adv. Protein Chem. 31 (1977) 1–133. [PMID: 73346]
4.  Takahashi, N., Takahashi, Y. and Putnam, F.W. Primary structure of blood coagulation factor XIIIa (fibrinoligase, transglutaminase) from human placenta. Proc. Natl. Acad. Sci. USA 83 (1986) 8019–8023. [PMID: 2877456]
[EC 2.3.2.13 created 1978, modified 1981, modified 1983]
 
 
EC 2.3.2.26     
Accepted name: HECT-type E3 ubiquitin transferase
Reaction: [E2 ubiquitin-conjugating enzyme]-S-ubiquitinyl-L-cysteine + [acceptor protein]-L-lysine = [E2 ubiquitin-conjugating enzyme]-L-cysteine + [acceptor protein]-N6-ubiquitinyl-L-lysine (overall reaction)
(1a) [E2 ubiquitin-conjugating enzyme]-S-ubiquitinyl-L-cysteine + [HECT-type E3 ubiquitin transferase]-L-cysteine = [E2 ubiquitin-conjugating enzyme]-L-cysteine + [HECT-type E3 ubiquitin transferase]-S-ubiquitinyl-L-cysteine
(1b) [HECT-type E3 ubiquitin transferase]-S-ubiquitinyl-L-cysteine + [acceptor protein]-L-lysine = [HECT-type E3 ubiquitin transferase]-L-cysteine + [acceptor protein]-N6-ubiquitinyl-L-lysine
Glossary: HECT protein domain = Homologous to the E6-AP Carboxyl Terminus protein domain
Other name(s): HECT E3 ligase (misleading); ubiquitin transferase HECT-E3; S-ubiquitinyl-[HECT-type E3-ubiquitin transferase]-L-cysteine:acceptor protein ubiquitin transferase (isopeptide bond-forming)
Systematic name: [E2 ubiquitin-conjugating enzyme]-S-ubiquitinyl-L-cysteine:[acceptor protein] ubiquitin transferase (isopeptide bond-forming)
Comments: In the first step the enzyme transfers ubiquitin from the E2 ubiquitin-conjugating enzyme (EC 2.3.2.23) to a cysteine residue in its HECT domain (which is located in the C-terminal region), forming a thioester bond. In a subsequent step the enzyme transfers the ubiquitin to an acceptor protein, resulting in the formation of an isopeptide bond between the C-terminal glycine residue of ubiquitin and the ε-amino group of an L-lysine residue of the acceptor protein. cf. EC 2.3.2.27, RING-type E3 ubiquitin transferase and EC 2.3.2.31, RBR-type E3 ubiquitin transferase.
References:
1.  Maspero, E., Mari, S., Valentini, E., Musacchio, A., Fish, A., Pasqualato, S. and Polo, S. Structure of the HECT:ubiquitin complex and its role in ubiquitin chain elongation. EMBO Rep. 12 (2011) 342–349. [PMID: 21399620]
2.  Metzger, M.B., Hristova, V.A. and Weissman, A.M. HECT and RING finger families of E3 ubiquitin ligases at a glance. J. Cell Sci. 125 (2012) 531–537. [PMID: 22389392]
[EC 2.3.2.26 created 2015, modified 2017]
 
 
EC 2.3.2.27     
Accepted name: RING-type E3 ubiquitin transferase
Reaction: [E2 ubiquitin-conjugating enzyme]-S-ubiquitinyl-L-cysteine + [acceptor protein]-L-lysine = [E2 ubiquitin-conjugating enzyme]-L-cysteine + [acceptor protein]-N6-ubiquitinyl-L-lysine
Glossary: RING = Really Interesting New Gene
Other name(s): RING E3 ligase (misleading); ubiquitin transferase RING E3; S-ubiquitinyl-[ubiquitin-conjugating E2 enzyme]-L-cysteine:acceptor protein ubiquitin transferase (isopeptide bond-forming, RING-type)
Systematic name: [E2 ubiquitin-conjugating enzyme]-S-ubiquitinyl-L-cysteine:[acceptor protein] ubiquitin transferase (isopeptide bond-forming; RING-type)
Comments: RING E3 ubiquitin transferases serve as mediators bringing the ubiquitin-charged E2 ubiquitin-conjugating enzyme (EC 2.3.2.23) and an acceptor protein together to enable the direct transfer of ubiquitin through the formation of an isopeptide bond between the C-terminal glycine residue of ubiquitin and the ε-amino group of an L-lysine residue of the acceptor protein. Unlike EC 2.3.2.26, HECT-type E3 ubiquitin transferase, the RING-E3 domain does not form a catalytic thioester intermediate with ubiquitin. Many members of the RING-type E3 ubiquitin transferase family are not able to bind a substrate directly, and form a complex with a cullin scaffold protein and a substrate recognition module (the complexes are named CRL for Cullin-RING-Ligase). In these complexes, the RING-type E3 ubiquitin transferase provides an additional function, mediating the transfer of a NEDD8 protein from a dedicated E2 carrier to the cullin protein (see EC 2.3.2.32, cullin-RING-type E3 NEDD8 transferase). cf. EC 2.3.2.31, RBR-type E3 ubiquitin transferase.
References:
1.  Eisele, F. and Wolf, D.H. Degradation of misfolded protein in the cytoplasm is mediated by the ubiquitin ligase Ubr1. FEBS Lett. 582 (2008) 4143–4146. [PMID: 19041308]
2.  Metzger, M.B., Hristova, V.A. and Weissman, A.M. HECT and RING finger families of E3 ubiquitin ligases at a glance. J. Cell Sci. 125 (2012) 531–537. [PMID: 22389392]
3.  Plechanovova, A., Jaffray, E.G., Tatham, M.H., Naismith, J.H. and Hay, R.T. Structure of a RING E3 ligase and ubiquitin-loaded E2 primed for catalysis. Nature 489 (2012) 115–120. [PMID: 22842904]
4.  Pruneda, J.N., Littlefield, P.J., Soss, S.E., Nordquist, K.A., Chazin, W.J., Brzovic, P.S. and Klevit, R.E. Structure of an E3:E2~Ub complex reveals an allosteric mechanism shared among RING/U-box ligases. Mol. Cell 47 (2012) 933–942. [PMID: 22885007]
5.  Metzger, M.B., Pruneda, J.N., Klevit, R.E. and Weissman, A.M. RING -type E3 ligases: master manipulators of E2 ubiquitin-conjugating enzymes and ubiquitination. Biochim. Biophys. Acta 1843 (2014) 47–60. [PMID: 23747565]
[EC 2.3.2.27 created 2015, modified 2017]
 
 
EC 2.3.2.35     
Accepted name: capsaicin synthase
Reaction: (6E)-8-methylnon-6-enoyl-CoA + vanillylamine = CoA + capsaicin
Other name(s): CS (gene name) (ambiguous); Pun1 (locus name)
Systematic name: (6E)-8-methylnon-6-enoyl-CoA:vanillylamine 8-methylnon-6-enoyltransferase
Comments: The enzyme, found only in plants that belong to the Capsicum genus, catalyses the last step in the biosynthesis of capsaicinoids. The enzyme catalyses the acylation of vanillylamine by a branched-chain fatty acid. The exact structure of the fatty acid determines the type of capsaicinoid formed.
References:
1.  Blum, E., Liu, K., Mazourek, M., Yoo, E.Y., Jahn, M. and Paran, I. Molecular mapping of the C locus for presence of pungency in Capsicum. Genome 45 (2002) 702–705. [PMID: 12175073]
2.  Stewart, C., Jr., Kang, B.C., Liu, K., Mazourek, M., Moore, S.L., Yoo, E.Y., Kim, B.D., Paran, I. and Jahn, M.M. The Pun1 gene for pungency in pepper encodes a putative acyltransferase. Plant J. 42 (2005) 675–688. [PMID: 15918882]
3.  Kim, S., Park, M., Yeom, S.I., Kim, Y.M., Lee, J.M., Lee, H.A., Seo, E., Choi, J., Cheong, K., Kim, K.T., Jung, K., Lee, G.W., Oh, S.K., Bae, C., Kim, S.B., Lee, H.Y., Kim, S.Y., Kim, M.S., Kang, B.C., Jo, Y.D., Yang, H.B., Jeong, H.J., Kang, W.H., Kwon, J.K., Shin, C., Lim, J.Y., Park, J.H., Huh, J.H., Kim, J.S., Kim, B.D., Cohen, O., Paran, I., Suh, M.C., Lee, S.B., Kim, Y.K., Shin, Y., Noh, S.J., Park, J., Seo, Y.S., Kwon, S.Y., Kim, H.A., Park, J.M., Kim, H.J., Choi, S.B., Bosland, P.W., Reeves, G., Jo, S.H., Lee, B.W., Cho, H.T., Choi, H.S., Lee, M.S., Yu, Y., Do Choi, Y., Park, B.S., van Deynze, A., Ashrafi, H., Hill, T., Kim, W.T., Pai, H.S., Ahn, H.K., Yeam, I., Giovannoni, J.J., Rose, J.K., Sorensen, I., Lee, S.J., Kim, R.W., Choi, I.Y., Choi, B.S., Lim, J.S., Lee, Y.H. and Choi, D. Genome sequence of the hot pepper provides insights into the evolution of pungency in Capsicum species. Nat. Genet. 46 (2014) 270–278. [PMID: 24441736]
[EC 2.3.2.35 created 2020]
 
 
EC 2.3.3.17     
Accepted name: methylthioalkylmalate synthase
Reaction: an ω-(methylsulfanyl)-2-oxoalkanoate + acetyl-CoA + H2O = a 2-[ω-(methylsulfanyl)alkyl]malate + CoA
Other name(s): MAM1 (gene name); MAM3 (gene name); acetyl-CoA:ω-(methylthio)-2-oxoalkanoate C-acetyltransferase
Systematic name: acetyl-CoA:ω-(methylsulfanyl)-2-oxoalkanoate C-acetyltransferase
Comments: The enzyme, characterized from the plant Arabidopsis thaliana, is involved in the L-methionine side-chain elongation pathway, forming substrates for the biosynthesis of aliphatic glucosinolates. Two forms are known - MAM1 catalyses only only the first two rounds of methionine chain elongation, while MAM3 catalyses all six cycles, up to formation of L-hexahomomethionine.
References:
1.  Textor, S., Bartram, S., Kroymann, J., Falk, K.L., Hick, A., Pickett, J.A. and Gershenzon, J. Biosynthesis of methionine-derived glucosinolates in Arabidopsis thaliana: recombinant expression and characterization of methylthioalkylmalate synthase, the condensing enzyme of the chain-elongation cycle. Planta 218 (2004) 1026–1035. [PMID: 14740211]
2.  Textor, S., de Kraker, J.W., Hause, B., Gershenzon, J. and Tokuhisa, J.G. MAM3 catalyzes the formation of all aliphatic glucosinolate chain lengths in Arabidopsis. Plant Physiol. 144 (2007) 60–71. [PMID: 17369439]
[EC 2.3.3.17 created 2016]
 
 
EC 2.4.1.46     
Accepted name: monogalactosyldiacylglycerol synthase
Reaction: UDP-α-D-galactose + a 1,2-diacyl-sn-glycerol = UDP + a 1,2-diacyl-3-O-(β-D-galactosyl)-sn-glycerol
Other name(s): uridine diphosphogalactose-1,2-diacylglycerol galactosyltransferase; UDP-galactose:diacylglycerol galactosyltransferase; MGDG synthase; UDP galactose-1,2-diacylglycerol galactosyltransferase; UDP-galactose-diacylglyceride galactosyltransferase; UDP-galactose:1,2-diacylglycerol 3-β-D-galactosyltransferase; 1β-MGDG; 1,2-diacylglycerol 3-β-galactosyltransferase; UDP-galactose:1,2-diacyl-sn-glycerol 3-β-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:1,2-diacyl-sn-glycerol 3-β-D-galactosyltransferase
Comments: This enzyme adds only one galactosyl group to the diacylglycerol; EC 2.4.1.241, digalactosyldiacylglycerol synthase, adds a galactosyl group to the product of the above reaction. There are three isoforms in Arabidopsis that can be divided into two types, A-type (MGD1) and B-type (MGD2 and MGD3). MGD1 is the isoform responsible for the bulk of monogalactosyldiacylglycerol (MGDG) synthesis in Arabidopsis [4].
References:
1.  Veerkamp, J.H. Biochemical changes in Bifidobacterium bifidum var. pennsylvanicus after cell-wall inhibition. VI. Biosynthesis of the galactosyldiglycerides. Biochim. Biophys. Acta 348 (1974) 23–34. [PMID: 4838219]
2.  Wenger, D.A., Petipas, J.W. and Pieringer, R.A. The metabolism of glyceride glycolipids. II. Biosynthesis of monogalactosyl diglyceride from uridine diphosphate galactose and diglyceride in brain. Biochemistry 7 (1968) 3700–3707. [PMID: 5681471]
3.  Miège, C., Maréchal, E., Shimojima, M., Awai, K., Block, M.A., Ohta, H., Takamiya, K., Douce, R. and Joyard, J. Biochemical and topological properties of type A MGDG synthase, a spinach chloroplast envelope enzyme catalyzing the synthesis of both prokaryotic and eukaryotic MGDG. Eur. J. Biochem. 265 (1999) 990–1001. [PMID: 10518794]
4.  Benning, C. and Ohta, H. Three enzyme systems for galactoglycerolipid biosynthesis are coordinately regulated in plants. J. Biol. Chem. 280 (2005) 2397–2400. [PMID: 15590685]
[EC 2.4.1.46 created 1972, modified 2003, modified 2005]
 
 
EC 2.4.1.85     
Accepted name: cyanohydrin β-glucosyltransferase
Reaction: UDP-α-D-glucose + (S)-4-hydroxymandelonitrile = UDP + (S)-4-hydroxymandelonitrile β-D-glucoside
Glossary: dhurrin = (S)-4-hydroxymandelonitrile β-D-glucoside
Other name(s): uridine diphosphoglucose-p-hydroxymandelonitrile glucosyltransferase; UDP-glucose-p-hydroxymandelonitrile glucosyltransferase; uridine diphosphoglucose-cyanohydrin glucosyltransferase; uridine diphosphoglucose:aldehyde cyanohydrin β-glucosyltransferase; UDP-glucose:(S)-4-hydroxymandelonitrile β-D-glucosyltransferase; UGT85B1; UDP-glucose:p-hydroxymandelonitrile-O-glucosyltransferase; UDP-D-glucose:(S)-4-hydroxymandelonitrile β-D-glucosyltransferase
Systematic name: UDP-α-D-glucose:(S)-4-hydroxymandelonitrile β-D-glucosyltransferase (configuration-inverting)
Comments: Acts on a wide range of substrates in vitro, including cyanohydrins, terpenoids, phenolics, hexanol derivatives and plant hormones, in a regiospecific manner [3]. This enzyme is involved in the biosynthesis of the cyanogenic glucoside dhurrin in sorghum, along with EC 1.14.14.36, tyrosine N-monooxygenase and EC 1.14.14.37, 4-hydroxyphenylacetaldehyde oxime monooxygenase. This reaction prevents the disocciation and release of toxic hydrogen cyanide [3].
References:
1.  Reay, P.F. and Conn, E.E. The purification and properties of a uridine diphosphate glucose: aldehyde cyanohydrin β-glucosyltransferase from sorghum seedlings. J. Biol. Chem. 249 (1974) 5826–5830. [PMID: 4416442]
2.  Jones, P.R., Møller, B.L. and Hoj, P.B. The UDP-glucose:p-hydroxymandelonitrile-O-glucosyltransferase that catalyzes the last step in synthesis of the cyanogenic glucoside dhurrin in Sorghum bicolor. Isolation, cloning, heterologous expression, and substrate specificity. J. Biol. Chem. 274 (1999) 35483–35491. [PMID: 10585420]
3.  Hansen, K.S., Kristensen, C., Tattersall, D.B., Jones, P.R., Olsen, C.E., Bak, S. and Møller, B.L. The in vitro substrate regiospecificity of recombinant UGT85B1, the cyanohydrin glucosyltransferase from Sorghum bicolor. Phytochemistry 64 (2003) 143–151. [PMID: 12946413]
4.  Busk, P.K. and Møller, B.L. Dhurrin synthesis in sorghum is regulated at the transcriptional level and induced by nitrogen fertilization in older plants. Plant Physiol. 129 (2002) 1222–1231. [PMID: 12114576]
5.  Kristensen, C., Morant, M., Olsen, C.E., Ekstrøm, C.T., Galbraith, D.W., Møller, B.L. and Bak, S. Metabolic engineering of dhurrin in transgenic Arabidopsis plants with marginal inadvertent effects on the metabolome and transcriptome. Proc. Natl. Acad. Sci. USA 102 (2005) 1779–1784. [PMID: 15665094]
[EC 2.4.1.85 created 1976, modified 2005]
 
 
EC 2.4.1.159     
Accepted name: flavonol-3-O-glucoside L-rhamnosyltransferase
Reaction: UDP-β-L-rhamnose + a flavonol 3-O-β-D-glucoside = UDP + a flavonol 3-O-[α-L-rhamnosyl-(1→6)-β-D-glucoside]
Glossary: UDP-β-L-rhamnose = UDP-6-deoxy-β-L-mannose
Other name(s): uridine diphosphorhamnose-flavonol 3-O-glucoside rhamnosyltransferase; UDP-rhamnose:flavonol 3-O-glucoside rhamnosyltransferase; UDP-L-rhamnose:flavonol-3-O-D-glucoside 6′′-O-L-rhamnosyltransferase
Systematic name: UDP-β-L-rhamnose:flavonol-3-O-β-D-glucoside 6′′-O-L-rhamnosyltransferase (configuration-inverting)
Comments: A configuration-inverting rhamnosyltransferase that converts flavonol 3-O-glucosides to 3-O-rutinosides. Also acts, more slowly, on rutin, quercetin 3-O-galactoside and flavonol 3-O-rhamnosides.
References:
1.  Kleinehollenhorst, G., Behrens, H., Pegels, G., Srunk, N. and Wiermann, R. Formation of flavonol 3-O-diglycosides and flavonol 3-O-triglycosides by enzyme extracts from anthers of Tulipa cv apeldoorn - characterization and activity of 3 different O-glycosyltransferases during anther development. Z. Natursforsch. C: Biosci. 37 (1982) 587–599.
2.  Jones, P., Messner, B., Nakajima, J., Schaffner, A.R. and Saito, K. UGT73C6 and UGT78D1, glycosyltransferases involved in flavonol glycoside biosynthesis in Arabidopsis thaliana. J. Biol. Chem. 278 (2003) 43910–43918. [PMID: 12900416]
[EC 2.4.1.159 created 1986, modified 2015]
 
 
EC 2.4.1.184     
Accepted name: galactolipid galactosyltransferase
Reaction: 2 a 1,2-diacyl-3-O-(β-D-galactosyl)-sn-glycerol = a 1,2-diacyl-3-O-[β-D-galactosyl-(1→6)-β-D-galactosyl]-sn-glycerol + a 1,2-diacyl-sn-glycerol
Glossary: a 1,2-diacyl-3-O-(β-D-galactosyl)-sn-glycerol = monogalactosyldiacylglycerol
Other name(s): galactolipid-galactolipid galactosyltransferase; galactolipid:galactolipid galactosyltransferase; interlipid galactosyltransferase; GGGT; DGDG synthase (ambiguous); digalactosyldiacylglycerol synthase (ambiguous); 3-(β-D-galactosyl)-1,2-diacyl-sn-glycerol:mono-3-(β-D-galactosyl)-1,2-diacyl-sn-glycerol β-D-galactosyltransferase; 3-(β-D-galactosyl)-1,2-diacyl-sn-glycerol:3-(β-D-galactosyl)-1,2-diacyl-sn-glycerol β-D-galactosyltransferase; SFR2 (gene name)
Systematic name: 1,2-diacyl-3-O-(β-D-galactosyl)-sn-glycerol:1,2-diacyl-3-O-(β-D-galactosyl)-sn-glycerol β-D-galactosyltransferase
Comments: The enzyme converts monogalactosyldiacylglycerol to digalactosyldiacylglycerol, trigalactosyldiacylglycerol and tetragalactosyldiacylglycerol. All residues are connected by β linkages. The activity is localized to chloroplast envelope membranes, but it does not contribute to net galactolipid synthesis in plants, which is performed by EC 2.4.1.46, monogalactosyldiacylglycerol synthase, and EC 2.4.1.241, digalactosyldiacylglycerol synthase. Note that the β,β-digalactosyldiacylglycerol formed by this enzyme is different from the more common α,β-digalactosyldiacylglycerol formed by EC 2.4.1.241. The enzyme provides an important mechanism for the stabilization of the chloroplast membranes during freezing and drought stress.
References:
1.  Dorne, A.-J., Block, M.A., Joyard, J. and Douce, R. The galactolipid-galactolipid galactosyltransferase is located on the outer surface of the outer-membrane of the chloroplast envelope. FEBS Lett. 145 (1982) 30–34.
2.  Heemskerk, J.W.M., Wintermans, J.F.G.M., Joyard, J., Block, M.A., Dorne, A.-J. and Douce, R. Localization of galactolipid:galactolipid galactosyltransferase and acyltransferase in outer envelope membrane of spinach chloroplasts. Biochim. Biophys. Acta 877 (1986) 281–289.
3.  Heemskerk, J.W.M., Jacobs, F.H.H. and Wintermans, J.F.G.M. UDPgalactose-independent synthesis of monogalactosyldiacylglycerol. An enzymatic activity of the spinach chloroplast envelope. Biochim. Biophys. Acta 961 (1988) 38–47.
4.  Kelly, A.A., Froehlich, J.E. and Dörmann, P. Disruption of the two digalactosyldiacylglycerol synthase genes DGD1 and DGD2 in Arabidopsis reveals the existence of an additional enzyme of galactolipid synthesis. Plant Cell 15 (2003) 2694–2706. [PMID: 14600212]
5.  Benning, C. and Ohta, H. Three enzyme systems for galactoglycerolipid biosynthesis are coordinately regulated in plants. J. Biol. Chem. 280 (2005) 2397–2400. [PMID: 15590685]
6.  Fourrier, N., Bedard, J., Lopez-Juez, E., Barbrook, A., Bowyer, J., Jarvis, P., Warren, G. and Thorlby, G. A role for SENSITIVE TO FREEZING2 in protecting chloroplasts against freeze-induced damage in Arabidopsis. Plant J. 55 (2008) 734–745. [PMID: 18466306]
7.  Moellering, E.R., Muthan, B. and Benning, C. Freezing tolerance in plants requires lipid remodeling at the outer chloroplast membrane. Science 330 (2010) 226–228. [PMID: 20798281]
[EC 2.4.1.184 created 1990, modified 2005, modified 2015]
 
 
EC 2.4.1.195     
Accepted name: N-hydroxythioamide S-β-glucosyltransferase
Reaction: (1) UDP-α-D-glucose + (Z)-2-phenyl-1-thioacetohydroximate = UDP + desulfoglucotropeolin
(2) UDP-α-D-glucose + an (E)-ω-(methylsulfanyl)alkyl-thiohydroximate = UDP + an aliphatic desulfoglucosinolate
(3) UDP-α-D-glucose + (E)-2-(1H-indol-3-yl)-1-thioacetohydroximate = UDP + desulfoglucobrassicin
Glossary: an aliphatic desulfoglucosinolate = an ω-(methylsulfanyl)alkylhydroximate S-glucoside
Other name(s): UGT74B1 (gene name); desulfoglucosinolate-uridine diphosphate glucosyltransferase; uridine diphosphoglucose-thiohydroximate glucosyltransferase; thiohydroximate β-D-glucosyltransferase; UDPG:thiohydroximate glucosyltransferase; thiohydroximate S-glucosyltransferase; thiohydroximate glucosyltransferase; UDP-glucose:thiohydroximate S-β-D-glucosyltransferase; UDP-glucose:N-hydroxy-2-phenylethanethioamide S-β-D-glucosyltransferase
Systematic name: UDP-α-D-glucose:N-hydroxy-2-phenylethanethioamide S-β-D-glucosyltransferase
Comments: The enzyme specifically glucosylates the thiohydroximate functional group. It is involved in the biosynthesis of glucosinolates in cruciferous plants, and acts on aliphatic, aromatic, and indolic substrates.
References:
1.  Jain, J.C., Reed, D.W., Groot Wassink, J.W.D. and Underhill, E.W. A radioassay of enzymes catalyzing the glucosylation and sulfation steps of glucosinolate biosynthesis in Brassica species. Anal. Biochem. 178 (1989) 137–140. [PMID: 2524977]
2.  Reed, D.W., Davin, L., Jain, J.C., Deluca, V., Nelson, L. and Underhill, E.W. Purification and properties of UDP-glucose:thiohydroximate glucosyltransferase from Brassica napus L. seedlings. Arch. Biochem. Biophys. 305 (1993) 526–532. [PMID: 8373190]
3.  Marillia, E.F., MacPherson, J.M., Tsang, E.W., Van Audenhove, K., Keller, W.A. and GrootWassink, J.W. Molecular cloning of a Brassica napus thiohydroximate S-glucosyltransferase gene and its expression in Escherichia coli. Physiol. Plant. 113 (2001) 176–184. [PMID: 12060294]
4.  Fahey, J.W., Zalcmann, A.T. and Talalay, P. The chemical diversity and distribution of glucosinolates and isothiocyanates among plants. Phytochemistry 56 (2001) 5–51. [PMID: 11198818]
5.  Grubb, C.D., Zipp, B.J., Ludwig-Muller, J., Masuno, M.N., Molinski, T.F. and Abel, S. Arabidopsis glucosyltransferase UGT74B1 functions in glucosinolate biosynthesis and auxin homeostasis. Plant J. 40 (2004) 893–908. [PMID: 15584955]
[EC 2.4.1.195 created 1992, modified 2006, modified 2018]
 
 
EC 2.4.1.214     
Accepted name: glycoprotein 3-α-L-fucosyltransferase
Reaction: GDP-β-L-fucose + N4-{β-D-GlcNAc-(1→2)-α-D-Man-(1→3)-[β-D-GlcNAc-(1→2)-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc}-L-asparaginyl-[protein] = GDP + N4-{β-D-GlcNAc-(1→2)-α-D-Man-(1→3)-[β-D-GlcNAc-(1→2)-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-[α-L-Fuc-(1→3)]-β-D-GlcNAc}-L-asparaginyl-[protein]
Other name(s): GDP-L-Fuc:N-acetyl-β-D-glucosaminide α1,3-fucosyltransferase; GDP-L-Fuc:Asn-linked GlcNAc α1,3-fucosyltransferase; GDP-fucose:β-N-acetylglucosamine (Fuc to (Fucα1→6GlcNAc)-Asn-peptide) α1→3-fucosyltransferase; GDP-L-fucose:glycoprotein (L-fucose to asparagine-linked N-acetylglucosamine of 4-N-{N-acetyl-β-D-glucosaminyl-(1→2)-α-D-mannosyl-(1→3)-[N-acetyl-β-D-glucosaminyl-(1→2)-α-D-mannosyl-(1→6)]-β-D-mannosyl-(1→4)-N-acetyl-β-D-glucosaminyl-(1→4)-N-acetyl-β-D-glucosaminyl}asparagine) 3-α-L-fucosyl-transferase; GDP-L-fucose:glycoprotein (L-fucose to asparagine-linked N-acetylglucosamine of N4-{N-acetyl-β-D-glucosaminyl-(1→2)-α-D-mannosyl-(1→3)-[N-acetyl-β-D-glucosaminyl-(1→2)-α-D-mannosyl-(1→6)]-β-D-mannosyl-(1→4)-N-acetyl-β-D-glucosaminyl-(1→4)-N-acetyl-β-D-glucosaminyl}asparagine) 3-α-L-fucosyl-transferase; GDP-β-L-fucose:glycoprotein (L-fucose to asparagine-linked N-acetylglucosamine of N4-{N-acetyl-β-D-glucosaminyl-(1→2)-α-D-mannosyl-(1→3)-[N-acetyl-β-D-glucosaminyl-(1→2)-α-D-mannosyl-(1→6)]-β-D-mannosyl-(1→4)-N-acetyl-β-D-glucosaminyl-(1→4)-N-acetyl-β-D-glucosaminyl}asparagine) 3-α-L-fucosyl-transferase
Systematic name: GDP-β-L-fucose:N4-{β-D-GlcNAc-(1→2)-α-D-Man-(1→3)-[β-D-GlcNAc-(1→2)-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc}-L-asparaginyl-[protein] 3-α-L-fucosyltransferase (configuration-retaining)
Comments: Requires Mn2+. The enzyme transfers to N-linked oligosaccharide structures (N-glycans), generally with a specificity for N-glycans with one unsubstituted non-reducing terminal GlcNAc residue. This enzyme catalyses a reaction similar to that of EC 2.4.1.68, glycoprotein 6-α-L-fucosyltransferase, but transferring the L-fucosyl group from GDP-β-L-fucose to form an α1,3-linkage rather than an α1,6-linkage. The N-glycan products of this enzyme are present in plants, insects and some other invertebrates (e.g., Schistosoma, Haemonchus, Lymnaea).
References:
1.  Wilson, I.B.H., Rendic, D., Freilinger, A., Dumic, J., Altmann, F., Mucha, J., Müller, S. and Hauser, M.-T. Cloning and expression of α1,3-fucosyltransferase homologues from Arabidopsis thaliana. Biochim. Biophys. Acta 1527 (2001) 88–96. [PMID: 11420147]
2.  Fabini, G., Freilinger, A., Altmann, F. and Wilson, I.B.H. Identification of core α1,3-fucosylated glycans and cloning of the requisite fucosyltransferase cDNA from Drosophila melanogaster. Potential basis of the neural anti-horseradish peroxidase epitope. J. Biol. Chem. 276 (2001) 28058–28067. [PMID: 11382750]
3.  Leiter, H., Mucha, J., Staudacher, E., Grimm, R., Glössl, J. and Altmann, F. Purification, cDNA cloning, and expression of GDP-L-Fuc:Asn-linked GlcNAc α1,3-fucosyltransferase from mung beans. J. Biol. Chem. 274 (1999) 21830–21839. [PMID: 10419500]
4.  van Tetering, A., Schiphorst, W.E.C.M., van den Eijnden, D.H. and van Die, I. Characterization of core α1→3-fucosyltransferase from the snail Lymnaea stagnalis that is involved in the synthesis of complex type N-glycans. FEBS Lett. 461 (1999) 311–314. [PMID: 10567717]
5.  Staudacher, E., Altmann, F., Glössl, J., März, L., Schachter, H., Kamerling, J.P., Haard, K. and Vliegenthart, J.F.G. GDP-fucose:β-N-acetylglucosamine (Fuc to (Fucα1→6GlcNAc)-Asn-peptide) α1→3-fucosyltransferase activity in honeybee (Apis mellifica) venom glands. The difucosylation of asparagine-bound N-acetylglucosamine. Eur. J. Biochem. 199 (1991) 745–751. [PMID: 1868856]
[EC 2.4.1.214 created 2001]
 
 
EC 2.4.1.241     
Accepted name: digalactosyldiacylglycerol synthase
Reaction: UDP-α-D-galactose + 1,2-diacyl-3-O-(β-D-galactosyl)-sn-glycerol = UDP + 1,2-diacyl-3-O-[α-D-galactosyl-(1→6)-β-D-galactosyl]-sn-glycerol
Other name(s): DGD1; DGD2; DGDG synthase (ambiguous); UDP-galactose-dependent DGDG synthase; UDP-galactose-dependent digalactosyldiacylglycerol synthase; UDP-galactose:MGDG galactosyltransferase; UDP-galactose:3-(β-D-galactosyl)-1,2-diacyl-sn-glycerol 6-α-galactosyltransferase
Systematic name: UDP-α-D-galactose:1,2-diacyl-3-O-(β-D-galactosyl)-sn-glycerol 6-α-galactosyltransferase
Comments: Requires Mg2+. Diacylglycerol cannot serve as an acceptor molecule for galactosylation as in the reaction catalysed by EC 2.4.1.46, monogalactosyldiacylglyerol synthase. When phosphate is limiting, phospholipids in plant membranes are reduced but these are replaced, at least in part, by the glycolipids digalactosyldiacylglycerol (DGDG) and sulfoquinovosyldiacylglycerol [3]. While both DGD1 and DGD2 are increased under phosphate-limiting conditions, DGD2 does not contribute significantly under optimal growth conditions. DGD2 is responsible for the synthesis of DGDG molecular species that are rich in C16 fatty acids at sn-1 of diacylglycerol whereas DGD1 leads to molecular species rich in C18 fatty acids [3]. The enzyme has been localized to the outer side of chloroplast envelope membranes.
References:
1.  Kelly, A.A. and Dörmann, P. DGD2, an Arabidopsis gene encoding a UDP-galactose-dependent digalactosyldiacylglycerol synthase is expressed during growth under phosphate-limiting conditions. J. Biol. Chem. 277 (2002) 1166–1173. [PMID: 11696551]
2.  Härtel, H., Dörmann, P. and Benning, C. DGD1-independent biosynthesis of extraplastidic galactolipids after phosphate deprivation in Arabidopsis. Proc. Natl. Acad. Sci. USA 97 (2000) 10649–10654. [PMID: 10973486]
3.  Kelly, A.A., Froehlich, J.E. and Dörmann, P. Disruption of the two digalactosyldiacylglycerol synthase genes DGD1 and DGD2 in Arabidopsis reveals the existence of an additional enzyme of galactolipid synthesis. Plant Cell 15 (2003) 2694–2706. [PMID: 14600212]
4.  Benning, C. and Ohta, H. Three enzyme systems for galactoglycerolipid biosynthesis are coordinately regulated in plants. J. Biol. Chem. 280 (2005) 2397–2400. [PMID: 15590685]
[EC 2.4.1.241 created 2005]
 
 
EC 2.4.1.260     
Accepted name: dolichyl-P-Man:Man7GlcNAc2-PP-dolichol α-1,6-mannosyltransferase
Reaction: dolichyl β-D-mannosyl phosphate + α-D-Man-(1→2)-α-D-Man-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→2)-α-D-Man-(1→3)-α-D-Man-(1→6)]-β-D-Man-β-(1→4)-β-D-GlcNAc-(1→4)-α-D-GlcNAc-diphosphodolichol = α-D-Man-α-(1→2)-α-D-Man-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→6)]-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-α-D-GlcNAc-diphosphodolichol + dolichyl phosphate
Other name(s): ALG12; ALG12 mannosyltransferase; ALG12 α1,6mannosyltransferase; dolichyl-P-mannose:Man7GlcNAc2-PP-dolichyl mannosyltransferase; dolichyl-P-Man:Man7GlcNAc2-PP-dolichyl α6-mannosyltransferase; EBS4; Dol-P-Man:Man7GlcNAc2-PP-Dol α-1,6-mannosyltransferase; dolichyl β-D-mannosyl phosphate:D-Man-α-(1→2)-D-Man-α-(1→2)-D-Man-α-(1→3)-[D-Man-α-(1→2)-D-Man-α-(1→3)-D-Man-α-(1→6)]-D-Man-β-(1→4)-D-GlcNAc-β-(1→4)-D-GlcNAc-diphosphodolichol α-1,6-mannosyltransferase
Systematic name: dolichyl β-D-mannosyl-phosphate:α-D-Man-(1→2)-α-D-Man-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→2)-α-D-Man-(1→3)-α-D-Man-(1→6)]-β-D-Man-β-(1→4)-β-D-GlcNAc-(1→4)-α-D-GlcNAc-diphosphodolichol 6-α-D-mannosyltransferase (configuration-inverting)
Comments: The formation of N-glycosidic linkages of glycoproteins involves the ordered assembly of the common Glc3Man9GlcNAc2 core-oligosaccharide on the lipid carrier dolichyl diphosphate. Early mannosylation steps occur on the cytoplasmic side of the endoplasmic reticulum with GDP-Man as donor, the final reactions from Man5GlcNAc2-PP-Dol to Man9Glc-NAc2-PP-Dol on the lumenal side use dolichyl β-D-mannosyl phosphate.
References:
1.  Frank, C.G. and Aebi, M. ALG9 mannosyltransferase is involved in two different steps of lipid-linked oligosaccharide biosynthesis. Glycobiology 15 (2005) 1156–1163. [PMID: 15987956]
2.  Hong, Z., Jin, H., Fitchette, A.C., Xia, Y., Monk, A.M., Faye, L. and Li, J. Mutations of an α1,6 mannosyltransferase inhibit endoplasmic reticulum-associated degradation of defective brassinosteroid receptors in Arabidopsis. Plant Cell 21 (2009) 3792–3802. [PMID: 20023196]
3.  Cipollo, J.F. and Trimble, R.B. The Saccharomyces cerevisiae alg12δ mutant reveals a role for the middle-arm α1,2Man- and upper-arm α1,2Manα1,6Man- residues of Glc3Man9GlcNAc2-PP-Dol in regulating glycoprotein glycan processing in the endoplasmic reticulum and Golgi apparatus. Glycobiology 12 (2002) 749–762. [PMID: 12460943]
4.  Grubenmann, C.E., Frank, C.G., Kjaergaard, S., Berger, E.G., Aebi, M. and Hennet, T. ALG12 mannosyltransferase defect in congenital disorder of glycosylation type lg. Hum. Mol. Genet. 11 (2002) 2331–2339. [PMID: 12217961]
[EC 2.4.1.260 created 1976 as EC 2.4.1.130, part transferred 2011 to EC 2.4.1.160, modified 2012]
 
 
EC 2.4.1.310     
Accepted name: vancomycin aglycone glucosyltransferase
Reaction: UDP-α-D-glucose + vancomycin aglycone = UDP + devancosaminyl-vancomycin
Glossary: devancosaminyl-vancomycin = vancomycin pseudoaglycone
Other name(s): GtfB (ambiguous)
Systematic name: UDP-α-D-glucose:vancomycin aglycone 48-O-β-glucosyltransferase
Comments: The enzyme from the bacterium Amycolatopsis orientalis is involved in the biosynthesis of the glycopeptide antibiotic chloroeremomycin.
References:
1.  Losey, H.C., Peczuh, M.W., Chen, Z., Eggert, U.S., Dong, S.D., Pelczer, I., Kahne, D. and Walsh, C.T. Tandem action of glycosyltransferases in the maturation of vancomycin and teicoplanin aglycones: novel glycopeptides. Biochemistry 40 (2001) 4745–4755. [PMID: 11294642]
2.  Mulichak, A.M., Losey, H.C., Walsh, C.T. and Garavito, R.M. Structure of the UDP-glucosyltransferase GtfB that modifies the heptapeptide aglycone in the biosynthesis of vancomycin group antibiotics. Structure 9 (2001) 547–557. [PMID: 11470430]
[EC 2.4.1.310 created 2013]
 
 
EC 2.4.1.311     
Accepted name: chloroorienticin B synthase
Reaction: dTDP-β-L-4-epi-vancosamine + desvancosaminyl-vancomycin = dTDP + chloroorienticin B
Glossary: dTDP-β-L-4-epi-vancosamine = dTDP-3-amino-2,3,6-trideoxy-3-methyl-β-L-arabino-hexopyranose
desvancosaminyl-vancomycin = vanomycin pseudoaglycone
Other name(s): GtfA
Systematic name: dTDP-L-4-epi-vancosamine:desvancosaminyl-vancomycin vancosaminyltransferase
Comments: The enzyme from the bacterium Amycolatopsis orientalis is involved in the biosynthesis of the glycopeptide antibiotic chloroeremomycin.
References:
1.  Mulichak, A.M., Losey, H.C., Lu, W., Wawrzak, Z., Walsh, C.T. and Garavito, R.M. Structure of the TDP-epi-vancosaminyltransferase GtfA from the chloroeremomycin biosynthetic pathway. Proc. Natl. Acad. Sci. USA 100 (2003) 9238–9243. [PMID: 12874381]
2.  Lu, W., Oberthur, M., Leimkuhler, C., Tao, J., Kahne, D. and Walsh, C.T. Characterization of a regiospecific epivancosaminyl transferase GtfA and enzymatic reconstitution of the antibiotic chloroeremomycin. Proc. Natl. Acad. Sci. USA 101 (2004) 4390–4395. [PMID: 15070728]
[EC 2.4.1.311 created 2013]
 
 
EC 2.4.1.315     
Accepted name: diglucosyl diacylglycerol synthase (1,6-linking)
Reaction: (1) UDP-α-D-glucose + 1,2-diacyl-3-O-(β-D-glucopyranosyl)-sn-glycerol = 1,2-diacyl-3-O-[β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl]-sn-glycerol + UDP
(2) UDP-α-D-glucose + 1,2-diacyl-3-O-[β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl]-sn-glycerol = 1,2-diacyl-3-O-[β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl]-sn-glycerol + UDP
Other name(s): monoglucosyl diacylglycerol (1→6) glucosyltransferase; MGlcDAG (1→6) glucosyltransferase; DGlcDAG synthase (ambiguous); UGT106B1; ypfP (gene name)
Systematic name: UDP-α-D-glucose:1,2-diacyl-3-O-(β-D-glucopyranosyl)-sn-glycerol 6-glucosyltransferase
Comments: The enzyme is found in several bacterial species. The enzyme from Bacillus subtilis is specific for glucose [1]. The enzyme from Mycoplasma genitalium can incoporate galactose with similar efficiency, but forms mainly 1,2-diacyl-diglucopyranosyl-sn-glycerol in vivo [3]. The enzyme from Staphylococcus aureus can also form glucosyl-glycero-3-phospho-(1′-sn-glycerol) [2].
References:
1.  Jorasch, P., Wolter, F.P., Zahringer, U. and Heinz, E. A UDP glucosyltransferase from Bacillus subtilis successively transfers up to four glucose residues to 1,2-diacylglycerol: expression of ypfP in Escherichia coli and structural analysis of its reaction products. Mol. Microbiol. 29 (1998) 419–430. [PMID: 9720862]
2.  Jorasch, P., Warnecke, D.C., Lindner, B., Zahringer, U. and Heinz, E. Novel processive and nonprocessive glycosyltransferases from Staphylococcus aureus and Arabidopsis thaliana synthesize glycoglycerolipids, glycophospholipids, glycosphingolipids and glycosylsterols. Eur. J. Biochem. 267 (2000) 3770–3783. [PMID: 10848996]
3.  Andres, E., Martinez, N. and Planas, A. Expression and characterization of a Mycoplasma genitalium glycosyltransferase in membrane glycolipid biosynthesis: potential target against mycoplasma infections. J. Biol. Chem. 286 (2011) 35367–35379. [PMID: 21835921]
[EC 2.4.1.315 created 2014]
 
 
EC 2.4.1.322     
Accepted name: devancosaminyl-vancomycin vancosaminetransferase
Reaction: dTDP-β-L-vancosamine + devancosaminyl-vancomycin = dTDP + vancomycin
Glossary: dTDP-β-L-vancosamine = dTDP-3-amino-2,3,6-trideoxy-3-C-methyl-β-L-lyxo-hexopyranose
Other name(s): devancosaminyl-vancomycin TDP-vancosaminyltransferase; GtfD; dTDP-β-L-vancomycin:desvancosaminyl-vancomycin β-L-vancosaminetransferase; desvancosaminyl-vancomycin vancosaminetransferase
Systematic name: dTDP-β-L-vancomycin:devancosaminyl-vancomycin β-L-vancosaminetransferase
Comments: The enzyme, isolated from the bacterium Amycolatopsis orientalis, catalyses the ultimate step in the biosynthesis of the antibiotic vancomycin.
References:
1.  Losey, H.C., Peczuh, M.W., Chen, Z., Eggert, U.S., Dong, S.D., Pelczer, I., Kahne, D. and Walsh, C.T. Tandem action of glycosyltransferases in the maturation of vancomycin and teicoplanin aglycones: novel glycopeptides. Biochemistry 40 (2001) 4745–4755. [PMID: 11294642]
2.  Mulichak, A.M., Lu, W., Losey, H.C., Walsh, C.T. and Garavito, R.M. Crystal structure of vancosaminyltransferase GtfD from the vancomycin biosynthetic pathway: interactions with acceptor and nucleotide ligands. Biochemistry 43 (2004) 5170–5180. [PMID: 15122882]
[EC 2.4.1.322 created 2014]
 
 
EC 2.4.2.19     
Accepted name: nicotinate-nucleotide diphosphorylase (carboxylating)
Reaction: β-nicotinate D-ribonucleotide + diphosphate + CO2 = pyridine-2,3-dicarboxylate + 5-phospho-α-D-ribose 1-diphosphate
Glossary: quinolinate = pyridine-2,3-dicarboxylate
Other name(s): quinolinate phosphoribosyltransferase (decarboxylating); quinolinic acid phosphoribosyltransferase; QAPRTase; NAD+ pyrophosphorylase; nicotinate mononucleotide pyrophosphorylase (carboxylating); quinolinic phosphoribosyltransferase
Systematic name: β-nicotinate-D-ribonucleotide:diphosphate phospho-α-D-ribosyltransferase (carboxylating)
Comments: The reaction is catalysed in the opposite direction. Since quinolinate is synthesized from L-tryptophan in eukaryotes, but from L-aspartate in some prokaryotes, this is the first NAD+ biosynthesis enzyme shared by both eukaryotes and prokaryotes [3].
References:
1.  Gholson, R.K., Ueda, I., Ogasawara, N. and Henderson, L.M. The enzymatic conversion of quinolinate to nicotinic acid mononucleotide in mammalian liver. J. Biol. Chem. 239 (1964) 1208–1214. [PMID: 14165928]
2.  Packman, P.M. and Jakoby, W.B. Crystalline quinolinate phosphoribosyltransferase. J. Biol. Chem. 240 (1965) 4107–4108. [PMID: 5320648]
3.  Katoh, A., Uenohara, K., Akita, M. and Hashimoto, T. Early steps in the biosynthesis of NAD in Arabidopsis start with aspartate and occur in the plastid. Plant Physiol. 141 (2006) 851–857. [PMID: 16698895]
[EC 2.4.2.19 created 1972]
 
 
EC 2.4.2.38     
Accepted name: glycoprotein 2-β-D-xylosyltransferase
Reaction: UDP-α-D-xylose + N4-{β-D-GlcNAc-(1→2)-α-D-Man-(1→3)-[β-D-GlcNAc-(1→2)-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc}-L-asparaginyl-[protein] = UDP + N4-{β-D-GlcNAc-(1→2)-α-D-Man-(1→3)-[β-D-GlcNAc-(1→2)-α-D-Man-(1→6)]-[β-D-Xyl-(1→2)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc}-L-asparaginyl-[protein]
Other name(s): β1,2-xylosyltransferase; UDP-D-xylose:glycoprotein (D-xylose to the 3,6-disubstituted mannose of 4-N-{N-acetyl-β-D-glucosaminyl-(1→2)-α-D-mannosyl-(1→3)-[N-acetyl-β-D-glucosaminyl-(1→2)-α-D-mannosyl-(1→6)]-β-D-mannosyl-(1→4)-N-acetyl-β-D-glucosaminyl-(1→4)-N-acetyl-β-D-glucosaminyl}asparagine) 2-β-D-xylosyltransferase; UDP-D-xylose:glycoprotein (D-xylose to the 3,6-disubstituted mannose of N4-{N-acetyl-β-D-glucosaminyl-(1→2)-α-D-mannosyl-(1→3)-[N-acetyl-β-D-glucosaminyl-(1→2)-α-D-mannosyl-(1→6)]-β-D-mannosyl-(1→4)-N-acetyl-β-D-glucosaminyl-(1→4)-N-acetyl-β-D-glucosaminyl}asparagine) 2-β-D-xylosyltransferase
Systematic name: UDP-α-D-xylose:N4-{β-D-GlcNAc-(1→2)-α-D-mannosyl-(1→3)-[β-D-GlcNAc-(1→2)-α-D-mannosyl-(1→6)]-β-D-mannosyl-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc}-L-asparaginyl-[protein] 2-β-D-xylosyltransferase (configuration-inverting)
Comments: Specific for N-linked oligosaccharides (N-glycans).
References:
1.  Zeng, Y., Bannon, G., Thomas, V.H., Rice, K., Drake, R. and Elbein, A. Purification and specificity of β1,2-xylosyltransferase, an enzyme that contributes to the allergenicity of some plant proteins. J. Biol. Chem. 272 (1997) 31340–31347. [PMID: 9395463]
2.  Strasser, R., Mucha, J., Mach, L., Altmann, F., Wilson, I.B., Glössl, J. and Steinkellner, H. Molecular cloning and functional expression of β1,2-xylosyltransferase cDNA from Arabidopsis thaliana. FEBS Lett. 472 (2000) 105–108. [PMID: 10781814]
[EC 2.4.2.38 created 2001]
 
 
EC 2.4.2.41     
Accepted name: xylogalacturonan β-1,3-xylosyltransferase
Reaction: Transfers a xylosyl residue from UDP-D-xylose to a D-galactose residue in xylogalacturonan, forming a β-1,3-D-xylosyl-D-galactose linkage.
Other name(s): xylogalacturonan xylosyltransferase; XGA xylosyltransferase
Systematic name: UDP-D-xylose:xylogalacturonan 3-β-D-xylosyltransferase
Comments: Involved in plant cell wall synthesis. The enzyme from Arabidopsis thaliana also transfers D-xylose from UDP-D-xylose onto oligogalacturonide acceptors. The enzyme did not show significant activity with UDP-glucose, UDP-galactose, or UDP-N-acetyl-D-glucosamine as sugar donors.
References:
1.  Jensen, J.K., Sorensen, S.O., Harholt, J., Geshi, N., Sakuragi, Y., Moller, I., Zandleven, J., Bernal, A.J., Jensen, N.B., Sorensen, C., Pauly, M., Beldman, G., Willats, W.G. and Scheller, H.V. Identification of a xylogalacturonan xylosyltransferase involved in pectin biosynthesis in Arabidopsis. Plant Cell 20 (2008) 1289–1302. [PMID: 18460606]
[EC 2.4.2.41 created 2009]
 
 
EC 2.4.2.51     
Accepted name: anthocyanidin 3-O-glucoside 2′′′-O-xylosyltransferase
Reaction: UDP-α-D-xylose + an anthocyanidin 3-O-β-D-glucoside = UDP + an anthocyanidin 3-O-β-D-sambubioside
Glossary: anthocyanidin 3-O-β-D-sambubioside = anthocyanidin 3-O-(β-D-xylosyl-(1→2)-β-D-glucoside)
Other name(s): uridine 5′-diphosphate-xylose:anthocyanidin 3-O-glucose-xylosyltransferase; UGT79B1
Systematic name: UDP-α-D-xylose:anthocyanidin-3-O-β-D-glucoside 2′′′-O-xylosyltransferase
Comments: Isolated from the plants Matthiola incana (stock) [1] and Arabidopsis thaliana (mouse-eared cress) [2]. The enzyme has similar activity with the 3-glucosides of pelargonidin, cyanidin, delphinidin, quercetin and kaempferol as well as with cyanidin 3-O-rhamnosyl-(1→6)-glucoside and cyanidin 3-O-(6-acylglucoside). There is no activity with other UDP-sugars or with cyanidin 3,5-diglucoside.
References:
1.  Teusch, M. Uridine 5′-diphosphate-xylose:anthocyanidin 3-O-glucose-xylosyltransferase from petals of Matthiola incana R.Br. Planta 169 (1986) 559–563. [PMID: 24232765]
2.  Yonekura-Sakakibara, K., Fukushima, A., Nakabayashi, R., Hanada, K., Matsuda, F., Sugawara, S., Inoue, E., Kuromori, T., Ito, T., Shinozaki, K., Wangwattana, B., Yamazaki, M. and Saito, K. Two glycosyltransferases involved in anthocyanin modification delineated by transcriptome independent component analysis in Arabidopsis thaliana. Plant J. 69 (2012) 154–167. [PMID: 21899608]
[EC 2.4.2.51 created 2013]
 
 
EC 2.4.2.58     
Accepted name: hydroxyproline O-arabinosyltransferase
Reaction: UDP-β-L-arabinofuranose + [protein]-trans-4-hydroxy-L-proline = UDP + [protein]-trans-4-(β-L-arabinofuranosyl)oxy-L-proline
Glossary: trans-4-hydroxy-L-proline = (2S,4R)-4-hydroxyproline = (4R)-4-hydroxy-L-proline
Other name(s): HPAT
Systematic name: UDP-β-L-arabinofuranose:[protein]-trans-4-hydroxy-L-proline L-arabinofuranosyl transferase (configuration-retaining)
Comments: The enzyme, found in plants and mosses, catalyses the O-arabinosylation of hydroxyprolines in hydroxyproline-rich glycoproteins. The enzyme acts on the first hydroxyproline in the motif Val-hydroxyPro-hydroxyPro-Ser.
References:
1.  Ogawa-Ohnishi, M., Matsushita, W. and Matsubayashi, Y. Identification of three hydroxyproline O-arabinosyltransferases in Arabidopsis thaliana. Nat. Chem. Biol. 9 (2013) 726–730. [PMID: 24036508]
[EC 2.4.2.58 created 2016]
 
 
EC 2.4.2.60     
Accepted name: cysteine-dependent adenosine diphosphate thiazole synthase
Reaction: NAD+ + glycine + [ADP-thiazole synthase]-L-cysteine = nicotinamide + ADP-5-ethyl-4-methylthiazole-2-carboxylate + [ADP-thiazole synthase]-dehydroalanine + 3 H2O
Other name(s): THI4 (gene name) (ambiguous); THI1 (gene name); ADP-thiazole synthase
Systematic name: NAD+:glycine ADP-D-ribosyltransferase (dehydroalanine-producing)
Comments: This iron dependent enzyme, found in fungi, plants, and some archaea, is involved in the thiamine phosphate biosynthesis pathway. It is a single turn-over enzyme since the cysteine residue is not regenerated in vivo [3]. The homologous enzyme in archaea (EC 2.4.2.59, sulfide-dependent adenosine diphosphate thiazole synthase) uses sulfide as sulfur donor.
References:
1.  Godoi, P.H., Galhardo, R.S., Luche, D.D., Van Sluys, M.A., Menck, C.F. and Oliva, G. Structure of the thiazole biosynthetic enzyme THI1 from Arabidopsis thaliana. J. Biol. Chem. 281 (2006) 30957–30966. [PMID: 16912043]
2.  Chatterjee, A., Abeydeera, N.D., Bale, S., Pai, P.J., Dorrestein, P.C., Russell, D.H., Ealick, S.E. and Begley, T.P. Saccharomyces cerevisiae THI4p is a suicide thiamine thiazole synthase. Nature 478 (2011) 542–546. [PMID: 22031445]
3.  Zhang, X., Eser, B.E., Chanani, P.K., Begley, T.P. and Ealick, S.E. Structural basis for iron-mediated sulfur transfer in archael and yeast thiazole synthases. Biochemistry 55 (2016) 1826–1838. [PMID: 26919468]
4.  Hwang, S., Cordova, B., Chavarria, N., Elbanna, D., McHugh, S., Rojas, J., Pfeiffer, F. and Maupin-Furlow, J.A. Conserved active site cysteine residue of archaeal THI4 homolog is essential for thiamine biosynthesis in Haloferax volcanii. BMC Microbiol. 14:260 (2014). [PMID: 25348237]
[EC 2.4.2.60 created 2018]
 
 
EC 2.4.99.14     
Accepted name: (Kdo)2-lipid IVA (2-8) 3-deoxy-D-manno-octulosonic acid transferase
Reaction: α-Kdo-(2→4)-α-Kdo-(2→6)-lipid IVA + CMP-β-Kdo = α-Kdo-(2→8)-α-Kdo-(2→4)-α-Kdo-(2→6)-lipid IVA + CMP
Glossary: (Kdo)2-lipid IVA = α-Kdo-(2→4)-α-Kdo-(2→6)-lipid IVA = (3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→4)-(3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→6)-2-deoxy-2-{[(3R)-3-hydroxytetradecanoyl]amino}-3-O-[(3R)-3-hydroxytetradecanoyl]-4-O-phosphono-β-D-glucopyranosyl-(1→6)-2-deoxy-3-O-[(3R)-3-hydroxytetradecanoyl]-2-{[(3R)-3-hydroxytetradecanoyl]amino}-1-O-phosphono-α-D-glucopyranose
(Kdo)3-lipid IVA = α-Kdo-(2→8)-α-Kdo-(2→4)-α-Kdo-(2→6)-lipid IVA = (3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→8)-(3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→4)-(3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→6)-2-deoxy-2-{[(3R)-3-hydroxytetradecanoyl]amino}-3-O-[(3R)-3-hydroxytetradecanoyl]-4-O-phosphono-β-D-glucopyranosyl-(1→6)-2-deoxy-3-O-[(3R)-3-hydroxytetradecanoyl]-2-{[(3R)-3-hydroxytetradecanoyl]amino}-1-O-phosphono-α-D-glucopyranose
CMP-β-Kdo = CMP-3-deoxy-β-D-manno-oct-2-ulopyranosylonate
Other name(s): Kdo transferase; waaA (gene name); kdtA (gene name); 3-deoxy-D-manno-oct-2-ulosonic acid transferase; 3-deoxy-manno-octulosonic acid transferase; (KDO)2-lipid IVA (2-8) 3-deoxy-D-manno-octulosonic acid transferase
Systematic name: CMP-3-deoxy-D-manno-oct-2-ulosonate:(Kdo)2-lipid IVA 3-deoxy-D-manno-oct-2-ulosonate transferase [(2→8) glycosidic bond-forming]
Comments: The enzymes from Chlamydia transfer three or more 3-deoxy-D-manno-oct-2-ulosonate residues and generate genus-specific epitopes.
References:
1.  Lobau, S., Mamat, U., Brabetz, W. and Brade, H. Molecular cloning, sequence analysis, and functional characterization of the lipopolysaccharide biosynthetic gene kdtA encoding 3-deoxy-α-D-manno-octulosonic acid transferase of Chlamydia pneumoniae strain TW-183. Mol. Microbiol. 18 (1995) 391–399. [PMID: 8748024]
2.  Mamat, U., Baumann, M., Schmidt, G. and Brade, H. The genus-specific lipopolysaccharide epitope of Chlamydia is assembled in C. psittaci and C. trachomatis by glycosyltransferases of low homology. Mol. Microbiol. 10 (1993) 935–941. [PMID: 7523826]
3.  Belunis, C.J., Mdluli, K.E., Raetz, C.R. and Nano, F.E. A novel 3-deoxy-D-manno-octulosonic acid transferase from Chlamydia trachomatis required for expression of the genus-specific epitope. J. Biol. Chem. 267 (1992) 18702–18707. [PMID: 1382060]
[EC 2.4.99.14 created 2010, modified 2011]
 
 
EC 2.4.99.15     
Accepted name: (Kdo)3-lipid IVA (2-4) 3-deoxy-D-manno-octulosonic acid transferase
Reaction: α-Kdo-(2→8)-α-Kdo-(2→4)-α-Kdo-(2→6)-lipid IVA + CMP-β-Kdo = α-Kdo-(2→8)-[α-Kdo-(2→4)]-α-Kdo-(2→4)-α-Kdo-(2→6)-lipid IVA + CMP
Glossary: (Kdo)3-lipid IVA = α-Kdo-(2→8)-α-Kdo-(2→4)-α-Kdo-(2→6)-lipid IVA = (3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→8)-(3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→4)-(3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→6)-2-deoxy-2-{[(3R)-3-hydroxytetradecanoyl]amino}-3-O-[(3R)-3-hydroxytetradecanoyl]-4-O-phosphono-β-D-glucopyranosyl-(1→6)-2-deoxy-3-O-[(3R)-3-hydroxytetradecanoyl]-2-{[(3R)-3-hydroxytetradecanoyl]amino}-1-O-phosphono-α-D-glucopyranose
(Kdo)4-lipid IVA = α-Kdo-(2→8)-[α-Kdo-(2→4)]-α-Kdo-(2→4)-α-Kdo-(2→6)-lipid IVA = (3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→8)-[(3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→4)]-(3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→4)-(3-deoxy-α-D-manno-oct-2-ulopyranosylonate)-(2→6)-2-deoxy-2-{[(3R)-3-hydroxytetradecanoyl]amino}-3-O-[(3R)-3-hydroxytetradecanoyl]-4-O-phosphono-β-D-glucopyranosyl-(1→6)-2-deoxy-3-O-[(3R)-3-hydroxytetradecanoyl]-2-{[(3R)-3-hydroxytetradecanoyl]amino}-1-O-phosphono-α-D-glucopyranose
CMP-β-Kdo = CMP-3-deoxy-β-D-manno-oct-2-ulopyranosylonate
Other name(s): Kdo transferase; waaA (gene name); kdtA (gene name); 3-deoxy-D-manno-oct-2-ulosonic acid transferase; 3-deoxy-manno-octulosonic acid transferase; (KDO)3-lipid IVA (2-4) 3-deoxy-D-manno-octulosonic acid transferase
Systematic name: CMP-3-deoxy-D-manno-oct-2-ulosonate:(Kdo)3-lipid IVA 3-deoxy-D-manno-oct-2-ulosonate transferase [(2→4) glycosidic bond-forming]
Comments: The enzyme from Chlamydia psittaci transfers four Kdo residues to lipid A, forming a branched tetrasaccharide with the structure α-Kdo-(2,8)-[α-Kdo-(2,4)]-α-Kdo-(2,4)-α-Kdo (cf. EC 2.4.99.12 [lipid IVA 3-deoxy-D-manno-octulosonic acid transferase], EC 2.4.99.13 [(Kdo)-lipid IVA 3-deoxy-D-manno-octulosonic acid transferase], and EC 2.4.99.14 [(Kdo)2-lipid IVA (2-8) 3-deoxy-D-manno-octulosonic acid transferase]).
References:
1.  Brabetz, W., Lindner, B. and Brade, H. Comparative analyses of secondary gene products of 3-deoxy-D-manno-oct-2-ulosonic acid transferases from Chlamydiaceae in Escherichia coli K-12. Eur. J. Biochem. 267 (2000) 5458–5465. [PMID: 10951204]
2.  Holst, O., Bock, K., Brade, L. and Brade, H. The structures of oligosaccharide bisphosphates isolated from the lipopolysaccharide of a recombinant Escherichia coli strain expressing the gene gseA [3-deoxy-D-manno-octulopyranosonic acid (Kdo) transferase] of Chlamydia psittaci 6BC. Eur. J. Biochem. 229 (1995) 194–200. [PMID: 7744029]
[EC 2.4.99.15 created 2010, modified 2011]
 
 
EC 2.5.1.3     
Accepted name: thiamine phosphate synthase
Reaction: (1) 4-amino-2-methyl-5-(diphosphooxymethyl)pyrimidine + 2-[(2R,5Z)-2-carboxy-4-methylthiazol-5(2H)-ylidene]ethyl phosphate = diphosphate + thiamine phosphate + CO2
(2) 4-amino-2-methyl-5-(diphosphooxymethyl)pyrimidine + 2-(2-carboxy-4-methylthiazol-5-yl)ethyl phosphate = diphosphate + thiamine phosphate + CO2
(3) 4-amino-2-methyl-5-(diphosphooxymethyl)pyrimidine + 4-methyl-5-(2-phosphooxyethyl)thiazole = diphosphate + thiamine phosphate
Other name(s): thiamine phosphate pyrophosphorylase; thiamine monophosphate pyrophosphorylase; TMP-PPase; thiamine-phosphate diphosphorylase; thiE (gene name); TH1 (gene name); THI6 (gene name); 2-methyl-4-amino-5-hydroxymethylpyrimidine-diphosphate:4-methyl-5-(2-phosphoethyl)thiazole 2-methyl-4-aminopyrimidine-5-methenyltransferase; 4-amino-2-methyl-5-diphosphomethylpyrimidine:2-[(2R,5Z)-2-carboxy-4-methylthiazol-5(2H)-ylidene]ethyl phosphate 4-amino-2-methylpyrimidine-5-methenyltransferase (decarboxylating)
Systematic name: 4-amino-2-methyl-5-(diphosphooxymethyl)pyrimidine:2-[(2R,5Z)-2-carboxy-4-methylthiazol-5(2H)-ylidene]ethyl phosphate 4-amino-2-methylpyrimidine-5-methenyltransferase (decarboxylating)
Comments: The enzyme catalyses the penultimate reaction in thiamine de novo biosynthesis, condensing the pyrimidine and thiazole components. The enzyme is thought to accept the product of EC 2.8.1.10, thiazole synthase, as its substrate. However, it has been shown that in some bacteria, such as Bacillus subtilis, an additional enzyme, thiazole tautomerase (EC 5.3.99.10) converts that compound into its tautomer 2-(2-carboxy-4-methylthiazol-5-yl)ethyl phosphate, and that it is the latter that serves as the substrate for the synthase. In addition to this activity, the enzyme participates in a salvage pathway, acting on 4-methyl-5-(2-phosphooxyethyl)thiazole, which is produced from thiamine degradation products. In yeast this activity is found in a bifunctional enzyme (THI6) and in the plant Arabidopsis thaliana the activity is part of a trifunctional enzyme (TH1).
References:
1.  Camiener, G.W. and Brown, G.M. The biosynthesis of thiamine. 2. Fractionation of enzyme system and identification of thiazole monophosphate and thiamine monophosphate as intermediates. J. Biol. Chem. 235 (1960) 2411–2417. [PMID: 13807175]
2.  Leder, I.G. The enzymatic synthesis of thiamine monophosphate. J. Biol. Chem. 236 (1961) 3066–3071. [PMID: 14463407]
3.  Kawasaki, Y. Copurification of hydroxyethylthiazole kinase and thiamine-phosphate pyrophosphorylase of Saccharomyces cerevisiae: characterization of hydroxyethylthiazole kinase as a bifunctional enzyme in the thiamine biosynthetic pathway. J. Bacteriol. 175 (1993) 5153–5158. [PMID: 8394314]
4.  Backstrom, A.D., McMordie, R.A.S. and Begley, T.P. Biosynthesis of thiamin I: the function of the thiE gene product. J. Am. Chem. Soc. 117 (1995) 2351–2352.
5.  Chiu, H.J., Reddick, J.J., Begley, T.P. and Ealick, S.E. Crystal structure of thiamin phosphate synthase from Bacillus subtilis at 1.25 Å resolution. Biochemistry 38 (1999) 6460–6470. [PMID: 10350464]
6.  Ajjawi, I., Tsegaye, Y. and Shintani, D. Determination of the genetic, molecular, and biochemical basis of the Arabidopsis thaliana thiamin auxotroph th1. Arch. Biochem. Biophys. 459 (2007) 107–114. [PMID: 17174261]
[EC 2.5.1.3 created 1965, modified 2015]
 
 
EC 2.5.1.15     
Accepted name: dihydropteroate synthase
Reaction: (7,8-dihydropterin-6-yl)methyl diphosphate + 4-aminobenzoate = diphosphate + 7,8-dihydropteroate
Glossary: 7,8-dihydropteroate = 4-{[(2-amino-4-oxo-3,4,7,8-tetrahydropteridin-6-yl)methyl]amino}benzoate
Other name(s): dihydropteroate pyrophosphorylase; DHPS; 7,8-dihydropteroate synthase; 7,8-dihydropteroate synthetase; 7,8-dihydropteroic acid synthetase; dihydropteroate synthetase; dihydropteroic synthetase; 2-amino-4-hydroxy-6-hydroxymethyl-7,8-dihydropteridine-diphosphate:4-aminobenzoate 2-amino-4-hydroxydihydropteridine-6-methenyltransferase; (2-amino-4-hydroxy-7,8-dihydropteridin-6-yl)methyl-diphosphate:4-aminobenzoate 2-amino-4-hydroxydihydropteridine-6-methenyltransferase
Systematic name: (7,8-dihydropterin-6-yl)methyl-diphosphate:4-aminobenzoate 2-amino-4-hydroxy-7,8-dihydropteridine-6-methenyltransferase
Comments: The enzyme participates in the biosynthetic pathways for folate (in bacteria, plants and fungi) and methanopterin (in archaea). The enzyme exists in varying types of multifunctional proteins in different organisms. The enzyme from the plant Arabidopsis thaliana also harbors the activity of EC 2.7.6.3, 2-amino-4-hydroxy-6-hydroxymethyldihydropteridine diphosphokinase [4], while the enzyme from yeast Saccharomyces cerevisiae is trifunctional with the two above mentioned activities as well as EC 4.1.2.25, dihydroneopterin aldolase [3].
References:
1.  Richey, D.P. and Brown, G.M. The biosynthesis of folic acid. IX. Purification and properties of the enzymes required for the formation of dihydropteroic acid. J. Biol. Chem. 244 (1969) 1582–1592. [PMID: 4304228]
2.  Shiota, T., Baugh, C.M., Jackson, R. and Dillard, R. The enzymatic synthesis of hydroxymethyldihydropteridine pyrophosphate and dihydrofolate. Biochemistry 8 (1969) 5022–5028. [PMID: 4312465]
3.  Güldener, U., Koehler, G.J., Haussmann, C., Bacher, A., Kricke, J., Becher, D. and Hegemann, J.H. Characterization of the Saccharomyces cerevisiae Fol1 protein: starvation for C1 carrier induces pseudohyphal growth. Mol. Biol. Cell 15 (2004) 3811–3828. [PMID: 15169867]
4.  Storozhenko, S., Navarrete, O., Ravanel, S., De Brouwer, V., Chaerle, P., Zhang, G.F., Bastien, O., Lambert, W., Rebeille, F. and Van Der Straeten, D. Cytosolic hydroxymethyldihydropterin pyrophosphokinase/dihydropteroate synthase from Arabidopsis thaliana: a specific role in early development and stress response. J. Biol. Chem. 282 (2007) 10749–10761. [PMID: 17289662]
[EC 2.5.1.15 created 1972, modified 2015]
 
 
EC 2.5.1.27     
Accepted name: adenylate dimethylallyltransferase (AMP-dependent)
Reaction: prenyl diphosphate + AMP = diphosphate + N6-prenyladenosine 5′-phosphate
Glossary: prenyl = 3-methylbut-2-en-1-yl = dimethylallyl (ambiguous)
Other name(s): cytokinin synthase (ambiguous); isopentenyltransferase (ambiguous); 2-isopentenyl-diphosphate:AMP Δ2-isopentenyltransferase; adenylate isopentenyltransferase (ambiguous); IPT; adenylate dimethylallyltransferase; dimethylallyl-diphosphate:AMP dimethylallyltransferase
Systematic name: prenyl-diphosphate:AMP prenyltransferase
Comments: Involved in the biosynthesis of cytokinins in plants. Some isoforms from the plant Arabidopsis thaliana are specific for AMP while others also have the activity of EC 2.5.1.112, adenylate dimethylallyltransferase (ADP/ATP-dependent).
References:
1.  Chen, C.-M. and Melitz, D.K. Cytokinin biosynthesis in a cell-free system from cytokinin-autotrophic tobacco tissue cultures. FEBS Lett. 107 (1979) 15–20. [PMID: 499537]
2.  Takei, K., Sakakibara, H. and Sugiyama, T. Identification of genes encoding adenylate isopentenyltransferase, a cytokinin biosynthesis enzyme, in Arabidopsis thaliana. J. Biol. Chem. 276 (2001) 26405–26410. [PMID: 11313355]
3.  Sakano, Y., Okada, Y., Matsunaga, A., Suwama, T., Kaneko, T., Ito, K., Noguchi, H. and Abe, I. Molecular cloning, expression, and characterization of adenylate isopentenyltransferase from hop (Humulus lupulus L.). Phytochemistry 65 (2004) 2439–2446. [PMID: 15381407]
[EC 2.5.1.27 created 1984, modified 2002, modified 2013]
 
 
EC 2.5.1.32     
Accepted name: 15-cis-phytoene synthase
Reaction: 2 geranylgeranyl diphosphate = 15-cis-phytoene + 2 diphosphate (overall reaction)
(1a) 2 geranylgeranyl diphosphate = diphosphate + prephytoene diphosphate
(1b) prephytoene diphosphate = 15-cis-phytoene + diphosphate
Other name(s): PSY (gene name); crtB (gene name); prephytoene-diphosphate synthase; phytoene synthetase; PSase; geranylgeranyl-diphosphate geranylgeranyltransferase
Systematic name: geranylgeranyl-diphosphate:geranylgeranyl-diphosphate geranylgeranyltransferase (15-cis-phytoene-forming)
Comments: Requires Mn2+ for activity. The enzyme condenses two molecules of geranylgeranyl diphosphate to give prephytoene diphosphate, followed by rearrangement of the cyclopropylcarbinyl intermediate to 15-cis-phytoene.
References:
1.  Chamovitz, D., Misawa, N., Sandmann, G. and Hirschberg, J. Molecular cloning and expression in Escherichia coli of a cyanobacterial gene coding for phytoene synthase, a carotenoid biosynthesis enzyme. FEBS Lett. 296 (1992) 305–310. [PMID: 1537409]
2.  Sandmann, G. and Misawa, N. New functional assignment of the carotenogenic genes crtB and crtE with constructs of these genes from Erwinia species. FEMS Microbiol. Lett. 69 (1992) 253–257. [PMID: 1555761]
3.  Scolnik, P.A. and Bartley, G.E. Nucleotide sequence of an Arabidopsis cDNA for phytoene synthase. Plant Physiol. 104 (1994) 1471–1472. [PMID: 8016277]
4.  Misawa, N., Truesdale, M.R., Sandmann, G., Fraser, P.D., Bird, C., Schuch, W. and Bramley, P.M. Expression of a tomato cDNA coding for phytoene synthase in Escherichia coli, phytoene formation in vivo and in vitro, and functional analysis of the various truncated gene products. J. Biochem. (Tokyo) 116 (1994) 980–985. [PMID: 7896759]
5.  Schledz, M., al-Babili, S., von Lintig, J., Haubruck, H., Rabbani, S., Kleinig, H. and Beyer, P. Phytoene synthase from Narcissus pseudonarcissus: functional expression, galactolipid requirement, topological distribution in chromoplasts and induction during flowering. Plant J. 10 (1996) 781–792. [PMID: 8953242]
[EC 2.5.1.32 created 1984, modified 2005, modified 2012]
 
 
EC 2.5.1.39     
Accepted name: 4-hydroxybenzoate polyprenyltransferase
Reaction: a polyprenyl diphosphate + 4-hydroxybenzoate = diphosphate + a 4-hydroxy-3-polyprenylbenzoate
Other name(s): nonaprenyl-4-hydroxybenzoate transferase; 4-hydroxybenzoate transferase; p-hydroxybenzoate dimethylallyltransferase; p-hydroxybenzoate polyprenyltransferase; p-hydroxybenzoic acid-polyprenyl transferase; p-hydroxybenzoic-polyprenyl transferase; 4-hydroxybenzoate nonaprenyltransferase
Systematic name: polyprenyl-diphosphate:4-hydroxybenzoate polyprenyltransferase
Comments: This enzyme, involved in the biosynthesis of ubiquinone, attaches a polyprenyl side chain to a 4-hydroxybenzoate ring, producing the first ubiquinone intermediate that is membrane bound. The number of isoprenoid subunits in the side chain varies in different species. The enzyme does not have any specificity concerning the length of the polyprenyl tail, and accepts tails of various lengths with similar efficiency [2,4,5].
References:
1.  Kalén, A., Appelkvist, E.-L., Chojnacki, T. and Dallner, G. Nonaprenyl-4-hydroxybenzoate transferase, an enzyme involved in ubiquinone biosynthesis, in the endoplasmic reticulum-Golgi system of rat liver. J. Biol. Chem. 265 (1990) 1158–1164. [PMID: 2295606]
2.  Melzer, M. and Heide, L. Characterization of polyprenyldiphosphate: 4-hydroxybenzoate polyprenyltransferase from Escherichia coli. Biochim. Biophys. Acta 1212 (1994) 93–102. [PMID: 8155731]
3.  Okada, K., Ohara, K., Yazaki, K., Nozaki, K., Uchida, N., Kawamukai, M., Nojiri, H. and Yamane, H. The AtPPT1 gene encoding 4-hydroxybenzoate polyprenyl diphosphate transferase in ubiquinone biosynthesis is required for embryo development in Arabidopsis thaliana. Plant Mol. Biol. 55 (2004) 567–577. [PMID: 15604701]
4.  Forsgren, M., Attersand, A., Lake, S., Grunler, J., Swiezewska, E., Dallner, G. and Climent, I. Isolation and functional expression of human COQ2, a gene encoding a polyprenyl transferase involved in the synthesis of CoQ. Biochem. J. 382 (2004) 519–526. [PMID: 15153069]
5.  Tran, U.C. and Clarke, C.F. Endogenous synthesis of coenzyme Q in eukaryotes. Mitochondrion 7 Suppl (2007) S62–S71. [PMID: 17482885]
[EC 2.5.1.39 created 1992, modified 2010]
 
 
EC 2.5.1.48     
Accepted name: cystathionine γ-synthase
Reaction: O4-succinyl-L-homoserine + L-cysteine = L-cystathionine + succinate
Other name(s): O-succinyl-L-homoserine succinate-lyase (adding cysteine); O-succinylhomoserine (thiol)-lyase; homoserine O-transsuccinylase (ambiguous); O-succinylhomoserine synthase; O-succinylhomoserine synthetase; cystathionine synthase; cystathionine synthetase; homoserine transsuccinylase (ambiguous); 4-O-succinyl-L-homoserine:L-cysteine S-(3-amino-3-carboxypropyl)transferase
Systematic name: O4-succinyl-L-homoserine:L-cysteine S-(3-amino-3-carboxypropyl)transferase
Comments: A pyridoxal-phosphate protein. Also reacts with hydrogen sulfide and methanethiol as replacing agents, producing homocysteine and methionine, respectively. In the absence of thiol, can also catalyse β,γ-elimination to form 2-oxobutanoate, succinate and ammonia.
References:
1.  Flavin, M. and Slaughter, C. Enzymatic synthesis of homocysteine or methionine directly from O-succinyl-homoserine. Biochim. Biophys. Acta 132 (1967) 400–405. [PMID: 5340123]
2.  Kaplan, M.M. and Flavin, M. Cystathionine γ-synthetase of Salmonella. Catalytic properties of a new enzyme in bacterial methionine biosynthesis. J. Biol. Chem. 241 (1966) 4463–4471. [PMID: 5922970]
3.  Wiebers, J.L. and Garner, H.R. Homocysteine and cysteine synthetases of Neurospora crassa. Purification, properties, and feedback control of activity. J. Biol. Chem. 242 (1967) 12–23. [PMID: 6016326]
4.  Wiebers, J.L. and Garner, H.R. Acyl derivatives of homoserine as substrates for homocysteine synthesis in Neurospora crassa, yeast, and Escherichia coli. J. Biol. Chem. 242 (1967) 5644–5649. [PMID: 12325384]
5.  Clausen, T., Huber, R., Prade, L., Wahl, M.C. and Messerschmidt, A. Crystal structure of Escherichia coli cystathionine γ-synthase at 1.5 Å resolution. EMBO J. 17 (1998) 6827–6838. [PMID: 9843488]
6.  Ravanel, S., Gakiere, B., Job, D. and Douce, R. Cystathionine γ-synthase from Arabidopsis thaliana: purification and biochemical characterization of the recombinant enzyme overexpressed in Escherichia coli. Biochem. J. 331 (1998) 639–648. [PMID: 9531508]
[EC 2.5.1.48 created 1972 as EC 4.2.99.9, transferred 2002 to EC 2.5.1.48]
 
 
EC 2.5.1.72     
Accepted name: quinolinate synthase
Reaction: glycerone phosphate + iminosuccinate = pyridine-2,3-dicarboxylate + 2 H2O + phosphate
Glossary: quinolinate = pyridine-2,3-dicarboxylate
glycerone phosphate = dihydroxyacetone phosphate = 3-hydroxy-2-oxopropyl phosphate
Other name(s): NadA; QS; quinolinate synthetase
Systematic name: glycerone phosphate:iminosuccinate alkyltransferase (cyclizing)
Comments: An iron-sulfur protein that requires a [4Fe-4S] cluster for activity [1]. Quinolinate synthase catalyses the second step in the de novo biosynthesis of NAD+ from aspartate in some bacteria, with EC 1.4.3.16 (L-aspartate oxidase) catalysing the first step and EC 2.4.2.19 [nicotinate-nucleotide diphosphorylase (carboxylating)] the third step. In Escherichia coli, two of the residues that are involved in the [4Fe-4S] cluster binding appear to undergo reversible disulfide-bond formation that regulates the activity of the enzyme [5].
References:
1.  Ollagnier-de Choudens, S., Loiseau, L., Sanakis, Y., Barras, F. and Fontecave, M. Quinolinate synthetase, an iron-sulfur enzyme in NAD biosynthesis. FEBS Lett. 579 (2005) 3737–3743. [PMID: 15967443]
2.  Katoh, A., Uenohara, K., Akita, M. and Hashimoto, T. Early steps in the biosynthesis of NAD in Arabidopsis start with aspartate and occur in the plastid. Plant Physiol. 141 (2006) 851–857. [PMID: 16698895]
3.  Sakuraba, H., Tsuge, H., Yoneda, K., Katunuma, N. and Ohshima, T. Crystal structure of the NAD biosynthetic enzyme quinolinate synthase. J. Biol. Chem. 280 (2005) 26645–26648. [PMID: 15937336]
4.  Rousset, C., Fontecave, M. and Ollagnier de Choudens, S. The [4Fe-4S] cluster of quinolinate synthase from Escherichia coli: Investigation of cluster ligands. FEBS Lett. 582 (2008) 2937–2944. [PMID: 18674537]
5.  Saunders, A.H. and Booker, S.J. Regulation of the activity of Escherichia coli quinolinate synthase by reversible disulfide-bond formation. Biochemistry 47 (2008) 8467–8469. [PMID: 18651751]
[EC 2.5.1.72 created 2008]
 
 
EC 2.5.1.79     
Accepted name: thermospermine synthase
Reaction: S-adenosyl 3-(methylsulfanyl)propylamine + spermidine = S-methyl-5′-thioadenosine + thermospermine + H+
Glossary: thermospermine = N1-[3-(3-aminopropylamino)propyl]butane-1,4-diamine
S-adenosyl 3-(methylsulfanyl)propylamine = (3-aminopropyl){[(2S,3S,4R,5R)-5-(6-amino-9H-purin-9-yl)-3,4-dihydroxytetrahydrofuran-2-yl]methyl}methylsulfonium
Other name(s): TSPMS; ACL5; SAC51; S-adenosyl 3-(methylthio)propylamine:spermidine 3-aminopropyltransferase (thermospermine synthesizing)
Systematic name: S-adenosyl 3-(methylsulfanyl)propylamine:spermidine 3-aminopropyltransferase (thermospermine-forming)
Comments: This plant enzyme is crucial for the proper functioning of xylem vessel elements in the vascular tissues of plants [3].
References:
1.  Romer, P., Faltermeier, A., Mertins, V., Gedrange, T., Mai, R. and Proff, P. Investigations about N-aminopropyl transferases probably involved in biomineralization. J. Physiol. Pharmacol. 59 Suppl 5 (2008) 27–37. [PMID: 19075322]
2.  Knott, J.M., Romer, P. and Sumper, M. Putative spermine synthases from Thalassiosira pseudonana and Arabidopsis thaliana synthesize thermospermine rather than spermine. FEBS Lett. 581 (2007) 3081–3086. [PMID: 17560575]
3.  Muniz, L., Minguet, E.G., Singh, S.K., Pesquet, E., Vera-Sirera, F., Moreau-Courtois, C.L., Carbonell, J., Blazquez, M.A. and Tuominen, H. ACAULIS5 controls Arabidopsis xylem specification through the prevention of premature cell death. Development 135 (2008) 2573–2582. [PMID: 18599510]
[EC 2.5.1.79 created 2010, modified 2013]
 
 
EC 2.5.1.85     
Accepted name: all-trans-nonaprenyl diphosphate synthase [geranylgeranyl-diphosphate specific]
Reaction: geranylgeranyl diphosphate + 5 isopentenyl diphosphate = 5 diphosphate + all-trans-nonaprenyl diphosphate
Glossary: solanesyl diphosphate = all-trans-nonaprenyll diphosphate
Other name(s): nonaprenyl diphosphate synthase (ambiguous); solanesyl diphosphate synthase (ambiguous); At-SPS2; At-SPS1; SPS1; SPS2
Systematic name: geranylgeranyl-diphosphate:isopentenyl-diphosphate transtransferase (adding 5 isopentenyl units)
Comments: Geranylgeranyl diphosphate is preferred over farnesyl diphosphate as allylic substrate [1]. The plant Arabidopsis thaliana has two different enzymes that catalyse this reaction. SPS1 contributes to the biosynthesis of the ubiquinone side-chain while SPS2 supplies the precursor of the plastoquinone side-chains [2].
References:
1.  Hirooka, K., Bamba, T., Fukusaki, E. and Kobayashi, A. Cloning and kinetic characterization of Arabidopsis thaliana solanesyl diphosphate synthase. Biochem. J. 370 (2003) 679–686. [PMID: 12437513]
2.  Hirooka, K., Izumi, Y., An, C.I., Nakazawa, Y., Fukusaki, E. and Kobayashi, A. Functional analysis of two solanesyl diphosphate synthases from Arabidopsis thaliana. Biosci. Biotechnol. Biochem. 69 (2005) 592–601. [PMID: 15784989]
3.  Jun, L., Saiki, R., Tatsumi, K., Nakagawa, T. and Kawamukai, M. Identification and subcellular localization of two solanesyl diphosphate synthases from Arabidopsis thaliana. Plant Cell Physiol. 45 (2004) 1882–1888. [PMID: 15653808]
[EC 2.5.1.85 created 1972 as EC 2.5.1.11, part transferred 2010 to EC 2.5.1.85]
 
 
EC 2.5.1.87     
Accepted name: ditrans,polycis-polyprenyl diphosphate synthase [(2E,6E)-farnesyl diphosphate specific]
Reaction: (2E,6E)-farnesyl diphosphate + n isopentenyl diphosphate = n diphosphate + ditrans,polycis-polyprenyl diphosphate (n = 10–55)
Other name(s): RER2; Rer2p; Rer2p Z-prenyltransferase; Srt1p; Srt2p Z-prenyltransferase; ACPT; dehydrodolichyl diphosphate synthase 1
Systematic name: (2E,6E)-farnesyl-diphosphate:isopentenyl-diphosphate cistransferase (adding 10–55 isopentenyl units)
Comments: The enzyme is involved in biosynthesis of dolichol (a long-chain polyprenol) with a saturated α-isoprene unit, which serves as a glycosyl carrier in protein glycosylation [1]. The yeast Saccharomyces cerevisiae has two different enzymes that catalyse this reaction. Rer2p synthesizes a well-defined family of polyprenols of 13–18 isoprene residues with dominating C80 (16 isoprene residues) extending to C120, while Srt1p synthesizes mainly polyprenol with 22 isoprene subunits. Largest Srt1p products reach C290 [2]. The enzyme from Arabidopsis thaliana catalyses the formation of polyprenyl diphosphates with predominant carbon number C120 [4].
References:
1.  Sato, M., Fujisaki, S., Sato, K., Nishimura, Y. and Nakano, A. Yeast Saccharomyces cerevisiae has two cis-prenyltransferases with different properties and localizations. Implication for their distinct physiological roles in dolichol synthesis. Genes Cells 6 (2001) 495–506. [PMID: 11442630]
2.  Poznanski, J. and Szkopinska, A. Precise bacterial polyprenol length control fails in Saccharomyces cerevisiae. Biopolymers 86 (2007) 155–164. [PMID: 17345630]
3.  Sato, M., Sato, K., Nishikawa, S., Hirata, A., Kato, J. and Nakano, A. The yeast RER2 gene, identified by endoplasmic reticulum protein localization mutations, encodes cis-prenyltransferase, a key enzyme in dolichol synthesis. Mol. Cell Biol. 19 (1999) 471–483. [PMID: 9858571]
4.  Oh, S.K., Han, K.H., Ryu, S.B. and Kang, H. Molecular cloning, expression, and functional analysis of a cis-prenyltransferase from Arabidopsis thaliana. Implications in rubber biosynthesis. J. Biol. Chem. 275 (2000) 18482–18488. [PMID: 10764783]
5.  Cunillera, N., Arro, M., Fores, O., Manzano, D. and Ferrer, A. Characterization of dehydrodolichyl diphosphate synthase of Arabidopsis thaliana, a key enzyme in dolichol biosynthesis. FEBS Lett. 477 (2000) 170–174. [PMID: 10908715]
[EC 2.5.1.87 created 2010]
 
 
EC 2.5.1.112     
Accepted name: adenylate dimethylallyltransferase (ADP/ATP-dependent)
Reaction: (1) prenyl diphosphate + ADP = diphosphate + N6-prenyladenosine 5′-diphosphate
(2) prenyl diphosphate + ATP = diphosphate + N6-prenyladenosine 5′-triphosphate
Other name(s): cytokinin synthase (ambiguous); isopentenyltransferase (ambiguous); 2-isopentenyl-diphosphate:ADP/ATP Δ2-isopentenyltransferase; adenylate isopentenyltransferase (ambiguous); dimethylallyl diphosphate:ATP/ADP isopentenyltransferase: IPT; dimethylallyl-diphosphate:ADP/ATP dimethylallyltransferase
Systematic name: prenyl-diphosphate:ADP/ATP prenyltransferase
Comments: Involved in the biosynthesis of cytokinins in plants. The IPT4 isoform from the plant Arabidopsis thaliana is specific for ADP and ATP [1]. Other isoforms, such as IPT1 from Arabidopsis thaliana [1,2] and the enzyme from the common hop, Humulus lupulus [3], also have a lower activity with AMP (cf. EC 2.5.1.27, adenylate dimethylallyltransferase).
References:
1.  Kakimoto, T. Identification of plant cytokinin biosynthetic enzymes as dimethylallyl diphosphate:ATP/ADP isopentenyltransferases. Plant Cell Physiol. 42 (2001) 677–685. [PMID: 11479373]
2.  Takei, K., Sakakibara, H. and Sugiyama, T. Identification of genes encoding adenylate isopentenyltransferase, a cytokinin biosynthesis enzyme, in Arabidopsis thaliana. J. Biol. Chem. 276 (2001) 26405–26410. [PMID: 11313355]
3.  Sakano, Y., Okada, Y., Matsunaga, A., Suwama, T., Kaneko, T., Ito, K., Noguchi, H. and Abe, I. Molecular cloning, expression, and characterization of adenylate isopentenyltransferase from hop (Humulus lupulus L.). Phytochemistry 65 (2004) 2439–2446. [PMID: 15381407]
[EC 2.5.1.112 created 2013]
 
 
EC 2.5.1.115     
Accepted name: homogentisate phytyltransferase
Reaction: phytyl diphosphate + homogentisate = diphosphate + 2-methyl-6-phytylbenzene-1,4-diol + CO2
Glossary: 2-methyl-6-phytylbenzene-1,4-diol = MPBQ
Other name(s): HPT; VTE2 (gene name)
Systematic name: phytyl-diphosphate:homogentisate phytyltransferase
Comments: Requires Mg2+ for activity [3]. Involved in the biosynthesis of the vitamin E tocopherols. While the enzyme from the cyanobacterium Synechocystis PCC 6803 has an appreciable activity with geranylgeranyl diphosphate (EC 2.5.1.116, homogentisate geranylgeranyltransferase), the enzyme from the plant Arabidopsis thaliana has only a low activity with that substrate [1,3,4].
References:
1.  Collakova, E. and DellaPenna, D. Isolation and functional analysis of homogentisate phytyltransferase from Synechocystis sp. PCC 6803 and Arabidopsis. Plant Physiol. 127 (2001) 1113–1124. [PMID: 11706191]
2.  Savidge, B., Weiss, J.D., Wong, Y.H., Lassner, M.W., Mitsky, T.A., Shewmaker, C.K., Post-Beittenmiller, D. and Valentin, H.E. Isolation and characterization of homogentisate phytyltransferase genes from Synechocystis sp. PCC 6803 and Arabidopsis. Plant Physiol. 129 (2002) 321–332. [PMID: 12011362]
3.  Sadre, R., Gruber, J. and Frentzen, M. Characterization of homogentisate prenyltransferases involved in plastoquinone-9 and tocochromanol biosynthesis. FEBS Lett. 580 (2006) 5357–5362. [PMID: 16989822]
4.  Yang, W., Cahoon, R.E., Hunter, S.C., Zhang, C., Han, J., Borgschulte, T. and Cahoon, E.B. Vitamin E biosynthesis: functional characterization of the monocot homogentisate geranylgeranyl transferase. Plant J. 65 (2011) 206–217. [PMID: 21223386]
[EC 2.5.1.115 created 2014]
 
 
EC 2.5.1.116     
Accepted name: homogentisate geranylgeranyltransferase
Reaction: geranylgeranyl diphosphate + homogentisate = diphosphate + 6-geranylgeranyl-2-methylbenzene-1,4-diol + CO2
Glossary: 6-geranylgeranyl-2-methylbenzene-1,4-diol = MGGBQ
Other name(s): HGGT; slr1736 (gene name)
Systematic name: geranylgeranyl-diphosphate:homogentisate geranylgeranyltransferase
Comments: Requires Mg2+ for activity. Involved in the biosynthesis of the vitamin E, tocotrienols. While the enzyme from the bacterium Synechocystis PCC 6803 has higher activity with phytyl diphosphate (EC 2.5.1.115, homogentisate phytyltransferase), the enzymes from barley, rice and wheat have only a low activity with that substrate [2].
References:
1.  Collakova, E. and DellaPenna, D. Isolation and functional analysis of homogentisate phytyltransferase from Synechocystis sp. PCC 6803 and Arabidopsis. Plant Physiol. 127 (2001) 1113–1124. [PMID: 11706191]
2.  Cahoon, E.B., Hall, S.E., Ripp, K.G., Ganzke, T.S., Hitz, W.D. and Coughlan, S.J. Metabolic redesign of vitamin E biosynthesis in plants for tocotrienol production and increased antioxidant content. Nat. Biotechnol. 21 (2003) 1082–1087. [PMID: 12897790]
3.  Yang, W., Cahoon, R.E., Hunter, S.C., Zhang, C., Han, J., Borgschulte, T. and Cahoon, E.B. Vitamin E biosynthesis: functional characterization of the monocot homogentisate geranylgeranyl transferase. Plant J. 65 (2011) 206–217. [PMID: 21223386]
[EC 2.5.1.116 created 2014]
 
 
EC 2.5.1.117     
Accepted name: homogentisate solanesyltransferase
Reaction: all-trans-nonaprenyl diphosphate + homogentisate = diphosphate + 2-methyl-6-all-trans-nonaprenylbenzene-1,4-diol + CO2
Glossary: 2-methyl-6-all-trans-nonaprenylbenzene-1,4-diol = 2-methyl-6-solanesylbenzene-1,4-diol = MSBQ
Other name(s): HST; PDS2 (gene name)
Systematic name: all-trans-nonaprenyl-diphosphate:homogentisate nonaprenyltransferase
Comments: Requires Mg2+ for activity. Part of the biosynthesis pathway of plastoquinol-9. The enzymes purified from the plant Arabidopsis thaliana and the alga Chlamydomonas reinhardtii are also active in vitro with unsaturated C10 to C20 prenyl diphosphates, producing main products that are not decarboxylated [2].
References:
1.  Sadre, R., Gruber, J. and Frentzen, M. Characterization of homogentisate prenyltransferases involved in plastoquinone-9 and tocochromanol biosynthesis. FEBS Lett. 580 (2006) 5357–5362. [PMID: 16989822]
2.  Sadre, R., Frentzen, M., Saeed, M. and Hawkes, T. Catalytic reactions of the homogentisate prenyl transferase involved in plastoquinone-9 biosynthesis. J. Biol. Chem. 285 (2010) 18191–18198. [PMID: 20400515]
[EC 2.5.1.117 created 2014]
 
 
EC 2.5.1.130     
Accepted name: 2-carboxy-1,4-naphthoquinone phytyltransferase
Reaction: phytyl diphosphate + 2-carboxy-1,4-naphthoquinone = demethylphylloquinone + diphosphate + CO2
Glossary: 2-carboxy-1,4-naphthoquinone = 1,4-dioxo-2-naphthoic acid
Other name(s): menA (gene name); ABC4 (gene name); 1,4-dioxo-2-naphthoate phytyltransferase; 1,4-diketo-2-naphthoate phytyltransferase
Systematic name: phytyl-diphosphate:2-carboxy-1,4-naphthoquinone phytyltransferase
Comments: This enzyme, found in plants and cyanobacteria, catalyses a step in the synthesis of phylloquinone (vitamin K1), an electron carrier associated with photosystem I. The enzyme catalyses the transfer of the phytyl chain synthesized by EC 1.3.1.83, geranylgeranyl diphosphate reductase, to 2-carboxy-1,4-naphthoquinone.
References:
1.  Johnson, T.W., Shen, G., Zybailov, B., Kolling, D., Reategui, R., Beauparlant, S., Vassiliev, I.R., Bryant, D.A., Jones, A.D., Golbeck, J.H. and Chitnis, P.R. Recruitment of a foreign quinone into the A(1) site of photosystem I. I. Genetic and physiological characterization of phylloquinone biosynthetic pathway mutants in Synechocystis sp. PCC 6803. J. Biol. Chem. 275 (2000) 8523–8530. [PMID: 10722690]
2.  Shimada, H., Ohno, R., Shibata, M., Ikegami, I., Onai, K., Ohto, M.A. and Takamiya, K. Inactivation and deficiency of core proteins of photosystems I and II caused by genetical phylloquinone and plastoquinone deficiency but retained lamellar structure in a T-DNA mutant of Arabidopsis. Plant J. 41 (2005) 627–637. [PMID: 15686525]
[EC 2.5.1.130 created 2015]
 
 
EC 2.5.1.144     
Accepted name: S-sulfo-L-cysteine synthase (O-acetyl-L-serine-dependent)
Reaction: O-acetyl-L-serine + thiosulfate = S-sulfo-L-cysteine + acetate
Glossary: O-acetyl-L-serine = (2S)-3-acetyloxy-2-aminopropanoic acid
Other name(s): cysteine synthase B; cysM (gene name); CS26 (gene name)
Systematic name: O-acetyl-L-serine:thiosulfate 2-amino-2-carboxyethyltransferase
Comments: In plants, the activity is catalysed by a chloroplastic enzyme that plays an important role in chloroplast function and is essential for light-dependent redox regulation within the chloroplast. The bacterial enzyme also catalyses the activity of EC 2.5.1.47, cysteine synthase. cf. EC 2.8.5.1, S-sulfo-L-cysteine synthase (3-phospho-L-serine-dependent).
References:
1.  Hensel, G. and Truper, H.G. O-Acetylserine sulfhydrylase and S-sulfocysteine synthase activities of Rhodospirillum tenue. Arch. Microbiol. 134 (1983) 227–232. [PMID: 6615127]
2.  Nakamura, T., Iwahashi, H. and Eguchi, Y. Enzymatic proof for the identity of the S-sulfocysteine synthase and cysteine synthase B of Salmonella typhimurium. J. Bacteriol. 158 (1984) 1122–1127. [PMID: 6373737]
3.  Bermudez, M.A., Paez-Ochoa, M.A., Gotor, C. and Romero, L.C. Arabidopsis S-sulfocysteine synthase activity is essential for chloroplast function and long-day light-dependent redox control. Plant Cell 22 (2010) 403–416. [PMID: 20179139]
4.  Bermudez, M.A., Galmes, J., Moreno, I., Mullineaux, P.M., Gotor, C. and Romero, L.C. Photosynthetic adaptation to length of day is dependent on S-sulfocysteine synthase activity in the thylakoid lumen. Plant Physiol. 160 (2012) 274–288. [PMID: 22829322]
5.  Gotor, C. and Romero, L.C. S-Sulfocysteine synthase function in sensing chloroplast redox status. Plant Signal. Behav. 8:e23313 (2013). [PMID: 23333972]
[EC 2.5.1.144 created 2018]
 
 
EC 2.5.1.149     
Accepted name: lycopene elongase/hydratase (flavuxanthin-forming)
Reaction: (1) prenyl diphosphate + all-trans-lycopene + acceptor + H2O = nonaflavuxanthin + reduced electron acceptor + diphosphate
(2) prenyl diphosphate + nonaflavuxanthin + acceptor + H2O = flavuxanthin + reduced electron acceptor + diphosphate
Glossary: flavuxanthin = 2,2′-bis-(4-hydroxy-3-methylbut-2-enyl)-1,16,1′,16′-tetradehydro-1,2,1′,2′-tetrahydro-ψ,ψ-carotene = (2E,8E,10E,12E,14E,16E,18E,20E,22E,24E,26E,28E,34E)-5,32-diisopropenyl-2,8,12,16,21,25,29,35-octamethylhexatriaconta-2,8,10,12,14,16,18,20,22,24,26,28,34-tridecaene-1,36-diol
Other name(s): crtEb (gene name); dimethylallyl-diphosphate:all-trans-lycopene dimethylallyltransferase (hydrating, flavuxanthin-forming)
Systematic name: prenyl-diphosphate:all-trans-lycopene prenyltransferase (hydrating, flavuxanthin-forming)
Comments: The enzyme, characterized from the bacterium Corynebacterium glutamicum, is bifunctional. It catalyses the elongation of the C40 carotenoid all-trans-lycopene by attaching an isoprene unit at C-2, as well as the hydroxylation of the new isoprene unit. The enzyme acts at both ends of the substrate, forming the C50 carotenoid flavuxanthin via the C45 intermediate nonaflavuxanthin. cf. EC 2.5.1.150, lycopene elongase/hydratase (dihydrobisanhydrobacterioruberin-forming).
References:
1.  Krubasik, P., Kobayashi, M. and Sandmann, G. Expression and functional analysis of a gene cluster involved in the synthesis of decaprenoxanthin reveals the mechanisms for C50 carotenoid formation. Eur. J. Biochem. 268 (2001) 3702–3708. [PMID: 11432736]
2.  Heider, S.A., Peters-Wendisch, P. and Wendisch, V.F. Carotenoid biosynthesis and overproduction in Corynebacterium glutamicum. BMC Microbiol. 12:198 (2012). [PMID: 22963379]
[EC 2.5.1.149 created 2018]
 
 
EC 2.5.1.150     
Accepted name: lycopene elongase/hydratase (dihydrobisanhydrobacterioruberin-forming)
Reaction: (1) prenyl diphosphate + all-trans-lycopene + H2O = dihydroisopentenyldehydrorhodopin + diphosphate
(2) prenyl diphosphate + isopentenyldehydrorhodopin + H2O = dihydrobisanhydrobacterioruberin + diphosphate
Glossary: dihydrobisanhydrobacterioruberin = (2S,2S′)-2,2′-bis(3-methylbut-2-en-1-yl)-3,3′,4,4′-tetradehydro-1,1′,2,2′-tetrahydro-ψ,ψ-carotene-1,1′-diol = (3S,4E,6E,8E,10E,12E,14E,16E,18E,20E,22E,24E,26E,30R)-2,6,10,14,19,23,27,31-octamethyl-3,30-bis(3-methylbut-2-en-1-yl)dotriaconta-4,6,8,10,12,14,16,18,20,22,24,26-dodecaene-2,31-diol
Other name(s): lbtA (gene name); lyeJ (gene name); dimethylallyl-diphosphate:all-trans-lycopene dimethylallyltransferase (hydrating, dihydrobisanhydrobacterioruberin-forming)
Systematic name: prenyl-diphosphate:all-trans-lycopene prenyltransferase (hydrating, dihydrobisanhydrobacterioruberin-forming)
Comments: The enzyme, characterized from the bacterium Dietzia sp. CQ4 and the halophilic archaea Halobacterium salinarum and Haloarcula japonica, is bifunctional. It catalyses the elongation of the C40 carotenoid all-trans-lycopene by attaching an isoprene unit at C-2 as well as the hydroxylation of the previous end of the molecule. The enzyme acts at both ends of the substrate, and combined with the action of EC 1.3.99.37, 1-hydroxy-2-isopentenylcarotenoid 3,4-desaturase, it forms the C50 carotenoid dihydrobisanhydrobacterioruberin. cf. EC 2.5.1.149, lycopene elongase/hydratase (flavuxanthin-forming).
References:
1.  Tao, L., Yao, H. and Cheng, Q. Genes from a Dietzia sp. for synthesis of C40 and C50 β-cyclic carotenoids. Gene 386 (2007) 90–97. [PMID: 17008032]
2.  Dummer, A.M., Bonsall, J.C., Cihla, J.B., Lawry, S.M., Johnson, G.C. and Peck, R.F. Bacterioopsin-mediated regulation of bacterioruberin biosynthesis in Halobacterium salinarum. J. Bacteriol. 193 (2011) 5658–5667. [PMID: 21840984]
3.  Yang, Y., Yatsunami, R., Ando, A., Miyoko, N., Fukui, T., Takaichi, S. and Nakamura, S. Complete biosynthetic pathway of the C50 carotenoid bacterioruberin from lycopene in the extremely halophilic archaeon Haloarcula japonica. J. Bacteriol. 197 (2015) 1614–1623. [PMID: 25712483]
[EC 2.5.1.150 created 2018]
 
 
EC 2.6.1.36     
Accepted name: L-lysine 6-transaminase
Reaction: L-lysine + 2-oxoglutarate = (S)-2-amino-6-oxohexanoate + L-glutamate
Glossary: (S)-2-amino-6-oxohexanoate = L-2-aminoadipate 6-semialdehyde = L-allysine
L-1-piperideine 6-carboxylate = (S)-2,3,4,5-tetrahydropyridine-2-carboxylate = (S)-1,6-didehydropiperidine-2-carboxylate
Other name(s): lysine 6-aminotransferase; lysine ε-aminotransferase; lysine ε-transaminase; lysine:2-ketoglutarate 6-aminotransferase; L-lysine-α-ketoglutarate aminotransferase; L-lysine-α-ketoglutarate 6-aminotransferase
Systematic name: L-lysine:2-oxoglutarate 6-aminotransferase
Comments: A pyridoxal-phosphate protein. The product (L-allysine) is converted into the intramolecularly dehydrated form, (S)-2,3,4,5-tetrahydropyridine-2-carboxylate.
References:
1.  Soda, K., Misono, H. and Yamamoto, T. L-Lysine:α-ketoglutarate aminotransferase. I. Identification of a product, δ-1-piperideine-6-carboxylic acid. Biochemistry 7 (1968) 4102–4109. [PMID: 5722275]
2.  Soda, K. and Misono, H. L-Lysine: α-ketoglutarate aminotransferase. II. Purification, crystallization, and properties. Biochemistry 7 (1968) 4110–4119. [PMID: 5722276]
[EC 2.6.1.36 created 1972, modified 2011]
 
 
EC 2.6.1.65     
Accepted name: N6-acetyl-β-lysine transaminase
Reaction: 6-acetamido-3-aminohexanoate + 2-oxoglutarate = 6-acetamido-3-oxohexanoate + L-glutamate
Other name(s): ε-acetyl-β-lysine aminotransferase
Systematic name: 6-acetamido-3-aminohexanoate:2-oxoglutarate aminotransferase
Comments: A pyridoxal-phosphate protein.
References:
1.  Bozler, G., Robertson, J.M., Ohsugi, M., Hensley, C. and Barker, H.A. Metabolism of L-β-lysine in a Pseudomonas: conversion of 6-N-acetyl-L-β-lysine to 3-keto-6-acetamidohexanoate and of 4-aminobutyrate to succinic semialdehyde by different transaminases. Arch. Biochem. Biophys. 197 (1979) 226–235. [PMID: 44448]
[EC 2.6.1.65 created 1984]
 
 
EC 2.6.1.85     
Accepted name: aminodeoxychorismate synthase
Reaction: chorismate + L-glutamine = 4-amino-4-deoxychorismate + L-glutamate (overall reaction)
(1a) L-glutamine + H2O = L-glutamate + NH3
(1b) chorismate + NH3 = 4-amino-4-deoxychorismate + H2O
Other name(s): ADC synthase; 4-amino-4-deoxychorismate synthase; PabAB; chorismate:L-glutamine amido-ligase (incorrect)
Systematic name: chorismate:L-glutamine aminotransferase
Comments: The enzyme is composed of two parts, a glutaminase (PabA in Escherichia coli) and an aminotransferase (PabB). In the absence of PabA and glutamine (but in the presence of Mg2+), PabB can convert ammonia and chorismate into 4-amino-4-deoxychorismate. PabA converts glutamine into glutamate only in the presence of stoichiometric amounts of PabB. In many organisms, including plants, the genes encoding the two proteins have fused to encode a single bifunctional protein. This enzyme is coupled with EC 4.1.3.38, aminodeoxychorismate lyase, to form 4-aminobenzoate. cf. EC 2.6.1.123, 4-amino-4-deoxychorismate synthase (2-amino-4-deoxychorismate-forming).
References:
1.  Ye, Q.Z., Liu, J. and Walsh, C.T. p-Aminobenzoate synthesis in Escherichia coli: purification and characterization of PabB as aminodeoxychorismate synthase and enzyme X as aminodeoxychorismate lyase. Proc. Natl. Acad. Sci. USA 87 (1990) 9391–9395. [PMID: 2251281]
2.  Viswanathan, V.K., Green, J.M. and Nichols, B.P. Kinetic characterization of 4-amino 4-deoxychorismate synthase from Escherichia coli. J. Bacteriol. 177 (1995) 5918–5923. [PMID: 7592344]
3.  Chang, Z., Sun, Y., He, J. and Vining, L.C. p-Aminobenzoic acid and chloramphenicol biosynthesis in Streptomyces venezuelae: gene sets for a key enzyme, 4-amino-4-deoxychorismate synthase. Microbiology (Reading) 147 (2001) 2113–2126. [PMID: 11495989]
4.  Camara, D., Richefeu-Contesto, C., Gambonnet, B., Dumas, R. and Rebeille, F. The synthesis of pABA: Coupling between the glutamine amidotransferase and aminodeoxychorismate synthase domains of the bifunctional aminodeoxychorismate synthase from Arabidopsis thaliana. Arch. Biochem. Biophys. 505 (2011) 83–90. [PMID: 20851095]
[EC 2.6.1.85 created 2003 as EC 6.3.5.8, transferred 2007 to EC 2.6.1.85, modified 2022]
 
 
EC 2.6.1.88     
Accepted name: methionine transaminase
Reaction: L-methionine + a 2-oxo carboxylate = 4-(methylsulfanyl)-2-oxobutanoate + an L-amino acid
Other name(s): methionine-oxo-acid transaminase
Systematic name: L-methionine:2-oxo-acid aminotransferase
Comments: The enzyme is most active with L-methionine. It participates in the L-methionine salvage pathway from S-methyl-5′-thioadenosine, a by-product of polyamine biosynthesis. The enzyme from the bacterium Klebsiella pneumoniae can use several different amino acids as amino donor, with aromatic amino acids being the most effective [1]. The enzyme from the plant Arabidopsis thaliana is also a part of the chain elongation pathway in the biosynthesis of methionine-derived glucosinolates [3].
References:
1.  Heilbronn, J., Wilson, J. and Berger, B.J. Tyrosine aminotransferase catalyzes the final step of methionine recycling in Klebsiella pneumoniae. J. Bacteriol. 181 (1999) 1739–1747. [PMID: 10074065]
2.  Dolzan, M., Johansson, K., Roig-Zamboni, V., Campanacci, V., Tegoni, M., Schneider, G. and Cambillau, C. Crystal structure and reactivity of YbdL from Escherichia coli identify a methionine aminotransferase function. FEBS Lett. 571 (2004) 141–146. [PMID: 15280032]
3.  Schuster, J., Knill, T., Reichelt, M., Gershenzon, J. and Binder, S. Branched-chain aminotransferase4 is part of the chain elongation pathway in the biosynthesis of methionine-derived glucosinolates in Arabidopsis. Plant Cell 18 (2006) 2664–2679. [PMID: 17056707]
[EC 2.6.1.88 created 2011]
 
 
EC 2.6.1.96     
Accepted name: 4-aminobutyrate—pyruvate transaminase
Reaction: (1) 4-aminobutanoate + pyruvate = succinate semialdehyde + L-alanine
(2) 4-aminobutanoate + glyoxylate = succinate semialdehyde + glycine
Other name(s): aminobutyrate aminotransferase (ambiguous); γ-aminobutyrate aminotransaminase (ambiguous); γ-aminobutyrate transaminase (ambiguous); γ-aminobutyric acid aminotransferase (ambiguous); γ-aminobutyric acid pyruvate transaminase; γ-aminobutyric acid transaminase (ambiguous); γ-aminobutyric transaminase (ambiguous); 4-aminobutyrate aminotransferase (ambiguous); 4-aminobutyric acid aminotransferase (ambiguous); aminobutyrate transaminase (ambiguous); GABA aminotransferase (ambiguous); GABA transaminase (ambiguous); GABA transferase (ambiguous); POP2 (gene name)
Systematic name: 4-aminobutanoate:pyruvate aminotransferase
Comments: Requires pyridoxal 5′-phosphate. The enzyme is found in plants that do not have the 2-oxoglutarate dependent enzyme (cf. EC 2.6.1.19). The reaction with pyruvate is reversible while the reaction with glyoxylate only takes place in the forward direction.
References:
1.  Van Cauwenberghe, O.R. and Shelp, B.J. Biochemical characterization of partially purified gaba:pyruvate transaminase from Nicotiana tabacum. Phytochemistry 52 (1999) 575–581.
2.  Palanivelu, R., Brass, L., Edlund, A.F. and Preuss, D. Pollen tube growth and guidance is regulated by POP2, an Arabidopsis gene that controls GABA levels. Cell 114 (2003) 47–59. [PMID: 12859897]
3.  Clark, S.M., Di Leo, R., Dhanoa, P.K., Van Cauwenberghe, O.R., Mullen, R.T. and Shelp, B.J. Biochemical characterization, mitochondrial localization, expression, and potential functions for an Arabidopsis γ-aminobutyrate transaminase that utilizes both pyruvate and glyoxylate. J. Exp. Bot. 60 (2009) 1743–1757. [PMID: 19264755]
4.  Clark, S.M., Di Leo, R., Van Cauwenberghe, O.R., Mullen, R.T. and Shelp, B.J. Subcellular localization and expression of multiple tomato γ-aminobutyrate transaminases that utilize both pyruvate and glyoxylate. J. Exp. Bot. 60 (2009) 3255–3267. [PMID: 19470656]
[EC 2.6.1.96 created 2012]
 
 
EC 2.6.1.99     
Accepted name: L-tryptophan—pyruvate aminotransferase
Reaction: L-tryptophan + pyruvate = indole-3-pyruvate + L-alanine
Other name(s): TAA1 (gene name); vt2 (gene name)
Systematic name: L-tryptophan:pyruvate aminotransferase
Comments: This plant enzyme, along with EC 1.14.13.168, indole-3-pyruvate monooxygenase, is responsible for the biosynthesis of the plant hormone indole-3-acetate from L-tryptophan.
References:
1.  Tao, Y., Ferrer, J.L., Ljung, K., Pojer, F., Hong, F., Long, J.A., Li, L., Moreno, J.E., Bowman, M.E., Ivans, L.J., Cheng, Y., Lim, J., Zhao, Y., Ballare, C.L., Sandberg, G., Noel, J.P. and Chory, J. Rapid synthesis of auxin via a new tryptophan-dependent pathway is required for shade avoidance in plants. Cell 133 (2008) 164–176. [PMID: 18394996]
2.  Mashiguchi, K., Tanaka, K., Sakai, T., Sugawara, S., Kawaide, H., Natsume, M., Hanada, A., Yaeno, T., Shirasu, K., Yao, H., McSteen, P., Zhao, Y., Hayashi, K., Kamiya, Y. and Kasahara, H. The main auxin biosynthesis pathway in Arabidopsis. Proc. Natl. Acad. Sci. USA 108 (2011) 18512–18517. [PMID: 22025724]
3.  Phillips, K.A., Skirpan, A.L., Liu, X., Christensen, A., Slewinski, T.L., Hudson, C., Barazesh, S., Cohen, J.D., Malcomber, S. and McSteen, P. vanishing tassel2 encodes a grass-specific tryptophan aminotransferase required for vegetative and reproductive development in maize. Plant Cell 23 (2011) 550–566. [PMID: 21335375]
4.  Zhao, Y. Auxin biosynthesis: a simple two-step pathway converts tryptophan to indole-3-acetic acid in plants. Mol. Plant 5 (2012) 334–338. [PMID: 22155950]
[EC 2.6.1.99 created 2012]
 
 
EC 2.6.1.103     
Accepted name: (S)-3,5-dihydroxyphenylglycine transaminase
Reaction: (S)-3,5-dihydroxyphenylglycine + 2-oxoglutarate = 2-(3,5-dihydroxyphenyl)-2-oxoacetate + L-glutamate
Glossary: (S)-3,5-dihydroxyphenylglycine = (2S)-2-amino-2-(3,5-dihydroxyphenyl)acetic acid
Other name(s): HpgT
Systematic name: (S)-3,5-dihydroxyphenylglycine:2-oxoglutarate aminotransferase
Comments: A pyridoxal-5′-phosphate protein. The enzyme from the bacterium Amycolatopsis orientalis catalyses the reaction in the reverse direction as part of the biosynthesis of the (S)-3,5-dihydroxyphenylglycine constituent of the glycopeptide antibiotic chloroeremomycin.
References:
1.  Sandercock, A.M., Charles, E.H., Scaife, W., Kirkpatrick, P.N., O'Brien, S.W., Papageorgiou, E.A., Spencer, J.B. and Williams, D.H. Biosynthesis of the di-meta-hydroxyphenylglycine constituent of the vancomycin-group antibiotic chloroeremomycin. Chem. Comm. (2001) 1252–1253.
[EC 2.6.1.103 created 2013]
 
 
EC 2.6.1.119     
Accepted name: vanillin aminotransferase
Reaction: L-alanine + vanillin = pyruvate + vanillylamine
Other name(s): VAMT (gene name)
Systematic name: L-alanine:vanillin aminotransferase
Comments: The enzyme participates in the biosynthesis of capsaicinoids in pungent cultivars of Capsicum sp. In vivo it has only been assayed in the reverse direction, where the preferred amino group acceptors were found to be pyruvate and oxaloacetate.
References:
1.  Curry, J., Aluru, M., Mendoza, M., Nevarez, J., Melendrez, M. and O'Connell, M.A. Transcripts for possible capsaicinoid biosynthetic genes are differentially accumulated in pungent and non-pungent Capsicum spp. Plant Sci. 148 (1999) 47–57.
2.  del Rosario Abraham-Juarez, M., del Carmen Rocha-Granados, M., Lopez, M.G., Rivera-Bustamante, R.F. and Ochoa-Alejo, N. Virus-induced silencing of Comt, pAmt and Kas genes results in a reduction of capsaicinoid accumulation in chili pepper fruits. Planta 227 (2008) 681–695. [PMID: 17999078]
3.  Lang, Y., Kisaka, H., Sugiyama, R., Nomura, K., Morita, A., Watanabe, T., Tanaka, Y., Yazawa, S. and Miwa, T. Functional loss of pAMT results in biosynthesis of capsinoids, capsaicinoid analogs, in Capsicum annuum cv. CH-19 Sweet. Plant J. 59 (2009) 953–961. [PMID: 19473323]
4.  Gururaj, H.B., Padma, M.N., Giridhar, P. and Ravishankar, G.A. Functional validation of Capsicum frutescens aminotransferase gene involved in vanillylamine biosynthesis using Agrobacterium mediated genetic transformation studies in Nicotiana tabacum and Capsicum frutescens calli cultures. Plant Sci. 195 (2012) 96–105. [PMID: 22921003]
5.  Weber, N., Ismail, A., Gorwa-Grauslund, M. and Carlquist, M. Biocatalytic potential of vanillin aminotransferase from Capsicum chinense. BMC Biotechnol 14:25 (2014). [PMID: 24712445]
[EC 2.6.1.119 created 2020]
 
 
EC 2.6.1.121     
Accepted name: 8-amino-7-oxononanoate carboxylating dehydrogenase
Reaction: (8S)-8-amino-7-oxononanoate + [protein]-L-lysine + CO2 = (7R,8S)-8-amino-7-(carboxyamino)nonanoate + [protein]-(S)-2-amino-6-oxohexanoate (overall reaction)
(1a) (8S)-8-amino-7-oxononanoate + [protein]-L-lysine + NAD(P)H + H+ = [protein]-N6-[(2S,3R)-2-amino-8-carboxyoctan-3-yl]-L-lysine + H2O + NAD(P)+
(1b) [protein]-N6-[(2S,3R)-2-amino-8-carboxyoctan-3-yl]-L-lysine + CO2 + H2O + NAD(P)+ = (7R,8S)-8-amino-7-(carboxyamino)nonanoate + [protein]-(S)-2-amino-6-oxohexanoate + NAD(P)H + H+
Other name(s): bioU (gene name)
Systematic name: (8S)-8-amino-7-oxononanoate:[protein]-L-lysine aminotransferase (N-carboxylating)
Comments: The enzyme, which participates in biotin biosynthesis, is found in haloarchaea and some cyanobacteria. It forms a conjugant between (7R,8S)-8-amino-7-oxononanoate and an internal lysine residue and catalyses multiple reactions, including a reduction, a carboxylation of the ε-amino group of the lysine residue, and an oxidative cleavage of the conjugate to release (7R,8S)-8-amino-7-(carboxyamino)nonanoate. During this process the lysine residue serves as an amino donor and is converted to (S)-2-amino-6-oxohexanoate, resulting in inactivation of the enzyme following a single turnover. cf. EC 2.6.1.105, lysine—8-amino-7-oxononanoate transaminase.
References:
1.  Sakaki, K., Ohishi, K., Shimizu, T., Kobayashi, I., Mori, N., Matsuda, K., Tomita, T., Watanabe, H., Tanaka, K., Kuzuyama, T. and Nishiyama, M. A suicide enzyme catalyzes multiple reactions for biotin biosynthesis in cyanobacteria. Nat. Chem. Biol. 16 (2020) 415–422. [PMID: 32042199]
[EC 2.6.1.121 created 2021]
 
 
EC 2.7.1.37      
Transferred entry: protein kinase. Now divided into EC 2.7.11.1 (non-specific serine/threonine protein kinase), EC 2.7.11.8 (Fas-activated serine/threonine kinase), EC 2.7.11.9 (Goodpasture-antigen-binding protein kinase), EC 2.7.11.10 (IκB kinase), EC 2.7.11.11 (cAMP-dependent protein kinase), EC 2.7.11.12 (cGMP-dependent protein kinase), EC 2.7.11.13 (protein kinase C), EC 2.7.11.21 (polo kinase), EC 2.7.11.22 (cyclin-dependent kinase), EC 2.7.11.24 (mitogen-activated protein kinase), EC 2.7.11.25 (mitogen-activated protein kinase kinase kinase), EC 2.7.11.30 (receptor protein serine/threonine kinase) and EC 2.7.12.1 (dual-specificity kinase)
[EC 2.7.1.37 created 1961 (EC 2.7.1.70 incorporated 2004), deleted 2005]
 
 
EC 2.7.1.97      
Deleted entry: opsin kinase. Identical with EC 2.7.11.14, rhodopsin kinase
[EC 2.7.1.97 created 1978, deleted 1992]
 
 
EC 2.7.1.123      
Transferred entry: Ca2+/calmodulin-dependent protein kinase. Now EC 2.7.11.17, Ca2+/calmodulin-dependent protein kinase
[EC 2.7.1.123 created 1989, deleted 2005]
 
 
EC 2.7.1.125      
Transferred entry: rhodopsin kinase. Now EC 2.7.11.14, rhodopsin kinase
[EC 2.7.1.125 created 1989 (EC 2.7.1.97 created 1978, incorporated 1992), deleted 2005]
 
 
EC 2.7.1.126      
Transferred entry: [β-adrenergic-receptor] kinase. Now EC 2.7.11.15, β-adrenergic-receptor kinase
[EC 2.7.1.126 created 1989, deleted 2005]
 
 
EC 2.7.1.151     
Accepted name: inositol-polyphosphate multikinase
Reaction: 2 ATP + 1D-myo-inositol 1,4,5-trisphosphate = 2 ADP + 1D-myo-inositol 1,3,4,5,6-pentakisphosphate (overall reaction)
(1a) ATP + 1D-myo-inositol 1,4,5-trisphosphate = ADP + 1D-myo-inositol 1,4,5,6-tetrakisphosphate
(1b) ATP + 1D-myo-inositol 1,4,5,6-tetrakisphosphate = ADP + 1D-myo-inositol 1,3,4,5,6-pentakisphosphate
Other name(s): IpK2; IP3/IP4 6-/3-kinase; IP3/IP4 dual-specificity 6-/3-kinase; IpmK; ArgRIII; AtIpk2α; AtIpk2β; inositol polyphosphate 6-/3-/5-kinase
Systematic name: ATP:1D-myo-inositol-1,4,5-trisphosphate 6-phosphotransferase
Comments: This enzyme also phosphorylates Ins(1,4,5)P3 to Ins(1,3,4,5)P4, Ins(1,3,4,5)P4 to Ins(1,3,4,5,6)P5, and Ins(1,3,4,5,6)P4 to Ins(PP)P4, isomer unknown. The enzyme from the plant Arabidopsis thaliana can also phosphorylate Ins(1,3,4,6)P4 and Ins(1,2,3,4,6)P5 at the D-5-position to produce 1,3,4,5,6-pentakisphosphate and inositol hexakisphosphate (InsP6), respectively [3]. Yeast produce InsP6 from Ins(1,4,5)P3 by the actions of this enzyme and EC 2.7.1.158, inositol-pentakisphosphate 2-kinase [4].
References:
1.  Saiardi, A., Erdjument-Bromage, H., Snowman, A.M., Tempst, P. and Snyder, S.H. Synthesis of diphosphoinositol pentakisphosphate by a newly identified family of higher inositol polyphosphate kinases. Curr. Biol. 9 (1999) 1323–1326. [PMID: 10574768]
2.  Odom, A.R., Stahlberg, A., Wente, S.R. and York, J.D. A role for nuclear inositol 1,4,5-trisphosphate kinase in transcriptional control. Science 287 (2000) 2026–2029. [PMID: 10720331]
3.  Stevenson-Paulik, J., Odom, A.R. and York, J.D. Molecular and biochemical characterization of two plant inositol polyphosphate 6-/3-/5-kinases. J. Biol. Chem. 277 (2002) 42711–42718. [PMID: 12226109]
4.  Verbsky, J.W., Chang, S.C., Wilson, M.P., Mochizuki, Y. and Majerus, P.W. The pathway for the production of inositol hexakisphosphate in human cells. J. Biol. Chem. 280 (2005) 1911–1920. [PMID: 15531582]
[EC 2.7.1.151 created 2002, modified 2006]
 
 
EC 2.7.1.172     
Accepted name: protein-ribulosamine 3-kinase
Reaction: ATP + [protein]-N6-D-ribulosyl-L-lysine = ADP + [protein]-N6-(3-O-phospho-D-ribulosyl)-L-lysine
Other name(s): Fn3KRP; FN3K-related protein; FN3K-RP; ketosamine 3-kinase 2; fructosamine-3-kinase-related protein; ribulosamine/erythrulosamine 3-kinase; ribulosamine 3-kinase
Systematic name: ATP:[protein]-N6-D-ribulosyl-L-lysine 3-phosphotransferase
Comments: This enzyme plays a role in freeing proteins from ribulosamines or psicosamines, which might arise from the reaction of amines with glucose and/or glycolytic intermediates. This role is shared by EC 2.7.1.171 (protein-fructosamine 3-kinase), which has, in addition, the unique capacity to phosphorylate fructosamines [1]. The plant enzyme also phosphorylates [protein]-N6-D-erythrulosyl-L-lysine [2]. No activity with [protein]-N6-D-fructosyl-L-lysine [1,2].
References:
1.  Collard, F., Delpierre, G., Stroobant, V., Matthijs, G. and Van Schaftingen, E. A mammalian protein homologous to fructosamine-3-kinase is a ketosamine-3-kinase acting on psicosamines and ribulosamines but not on fructosamines. Diabetes 52 (2003) 2888–2895. [PMID: 14633848]
2.  Fortpied, J., Gemayel, R., Stroobant, V. and van Schaftingen, E. Plant ribulosamine/erythrulosamine 3-kinase, a putative protein-repair enzyme. Biochem. J. 388 (2005) 795–802. [PMID: 15705060]
3.  Payne, L.S., Brown, P.M., Middleditch, M., Baker, E., Cooper, G.J. and Loomes, K.M. Mapping of the ATP-binding domain of human fructosamine 3-kinase-related protein by affinity labelling with 5′-[p-(fluorosulfonyl)benzoyl]adenosine. Biochem. J. 416 (2008) 281–288. [PMID: 18637789]
[EC 2.7.1.172 created 2011]
 
 
EC 2.7.1.176     
Accepted name: UDP-N-acetylglucosamine kinase
Reaction: ATP + UDP-N-acetyl-α-D-glucosamine = ADP + UDP-N-acetyl-α-D-glucosamine 3′-phosphate
Other name(s): UNAG kinase; ζ toxin; toxin PezT; ATP:UDP-N-acetyl-D-glucosamine 3′-phosphotransferase
Systematic name: ATP:UDP-N-acetyl-α-D-glucosamine 3′-phosphotransferase
Comments: Toxic component of a toxin-antitoxin (TA) module. The phosphorylation of UDP-N-acetyl-D-glucosamine results in the inhibition of EC 2.5.1.7, UDP-N-acetylglucosamine 1-carboxyvinyltransferase, the first committed step in cell wall synthesis, which is then blocked. The activity of this enzyme is inhibited when the enzyme binds to the cognate ε antitoxin.
References:
1.  Khoo, S.K., Loll, B., Chan, W.T., Shoeman, R.L., Ngoo, L., Yeo, C.C. and Meinhart, A. Molecular and structural characterization of the PezAT chromosomal toxin-antitoxin system of the human pathogen Streptococcus pneumoniae. J. Biol. Chem. 282 (2007) 19606–19618. [PMID: 17488720]
2.  Mutschler, H., Gebhardt, M., Shoeman, R.L. and Meinhart, A. A novel mechanism of programmed cell death in bacteria by toxin-antitoxin systems corrupts peptidoglycan synthesis. PLoS Biol. 9:e1001033 (2011). [PMID: 21445328]
[EC 2.7.1.176 created 2012]
 
 
EC 2.7.1.179     
Accepted name: kanosamine kinase
Reaction: ATP + kanosamine = ADP + kanosamine 6-phosphate
Glossary: kanosamine = 3-amino-3-deoxy-D-glucose
Other name(s): rifN (gene name)
Systematic name: ATP:kanosamine 6-phosphotransferase
Comments: The enzyme from the bacterium Amycolatopsis mediterranei is specific for kanosamine.
References:
1.  Arakawa, K., Muller, R., Mahmud, T., Yu, T.W. and Floss, H.G. Characterization of the early stage aminoshikimate pathway in the formation of 3-amino-5-hydroxybenzoic acid: the RifN protein specifically converts kanosamine into kanosamine 6-phosphate. J. Am. Chem. Soc. 124 (2002) 10644–10645. [PMID: 12207505]
[EC 2.7.1.179 created 2013]
 
 
EC 2.7.1.182     
Accepted name: phytol kinase
Reaction: CTP + phytol = CDP + phytyl phosphate
Other name(s): VTE5 (gene name)
Systematic name: CTP:phytol O-phosphotransferase
Comments: The enzyme is found in plants and photosynthetic algae [2] and is involved in phytol salvage [1]. It can use UTP as an alternative phosphate donor with lower activity [2].
References:
1.  Ischebeck, T., Zbierzak, A.M., Kanwischer, M. and Dormann, P. A salvage pathway for phytol metabolism in Arabidopsis. J. Biol. Chem. 281 (2006) 2470–2477. [PMID: 16306049]
2.  Valentin, H.E., Lincoln, K., Moshiri, F., Jensen, P.K., Qi, Q., Venkatesh, T.V., Karunanandaa, B., Baszis, S.R., Norris, S.R., Savidge, B., Gruys, K.J. and Last, R.L. The Arabidopsis vitamin E pathway gene5-1 mutant reveals a critical role for phytol kinase in seed tocopherol biosynthesis. Plant Cell 18 (2006) 212–224. [PMID: 16361393]
[EC 2.7.1.182 created 2014]
 
 
EC 2.7.1.216     
Accepted name: farnesol kinase
Reaction: CTP + (2E,6E)-farnesol = CDP + (2E,6E)-farnesyl phosphate
Other name(s): FOLK (gene name)
Systematic name: CTP:(2E,6E)-farnesol phosphotransferase
Comments: The enzyme, found in plants and animals, can also use other nucleotide triphosphates as phosphate donor, albeit less efficiently. The plant enzyme can also use geraniol and geranylgeraniol as substrates with lower activity, but not farnesyl phosphate (cf. EC 2.7.4.32, farnesyl phosphate kinase) [2].
References:
1.  Bentinger, M., Grunler, J., Peterson, E., Swiezewska, E. and Dallner, G. Phosphorylation of farnesol in rat liver microsomes: properties of farnesol kinase and farnesyl phosphate kinase. Arch. Biochem. Biophys. 353 (1998) 191–198. [PMID: 9606952]
2.  Fitzpatrick, A.H., Bhandari, J. and Crowell, D.N. Farnesol kinase is involved in farnesol metabolism, ABA signaling and flower development in Arabidopsis. Plant J. 66 (2011) 1078–1088. [PMID: 21395888]
[EC 2.7.1.216 created 2017]
 
 
EC 2.7.1.218     
Accepted name: fructoselysine 6-kinase
Reaction: ATP + N6-(D-fructosyl)-L-lysine = ADP + N6-(6-phospho-D-fructosyl)-L-lysine
Other name(s): frlD (gene name)
Systematic name: ATP:D-fructosyl-L-lysine 6-phosphotransferase
Comments: The enzyme, characterized from the bacterium Escherichia coli, has very little activity with fructose.
References:
1.  Wiame, E., Delpierre, G., Collard, F. and Van Schaftingen, E. Identification of a pathway for the utilization of the Amadori product fructoselysine in Escherichia coli. J. Biol. Chem. 277 (2002) 42523–42529. [PMID: 12147680]
2.  Wiame, E. and Van Schaftingen, E. Fructoselysine 3-epimerase, an enzyme involved in the metabolism of the unusual Amadori compound psicoselysine in Escherichia coli. Biochem. J. 378 (2004) 1047–1052. [PMID: 14641112]
[EC 2.7.1.218 created 2017]
 
 
EC 2.7.1.222     
Accepted name: 4-hydroxytryptamine kinase
Reaction: ATP + 4-hydroxytryptamine = ADP + 4-hydroxytryptamine 4-phosphate
Glossary: psilocybin = 3-[2-(dimethylamino)ethyl]-1H-indol-4-yl phosphate
Other name(s): PsiK
Systematic name: ATP:4-hydroxytryptamine 4-phosphotransferase
Comments: Also acts on 4-hydroxy-L-tryptophan in vitro. Isolated from the fungus Psilocybe cubensis. Involved in the biosynthesis of the psychoactive compound psilocybin.
References:
1.  Fricke, J., Blei, F. and Hoffmeister, D. Enzymatic synthesis of psilocybin. Angew. Chem. Int. Ed. Engl. 56 (2017) 12352–12355. [PMID: 28763571]
[EC 2.7.1.222 created 2017]
 
 
EC 2.7.2.4     
Accepted name: aspartate kinase
Reaction: ATP + L-aspartate = ADP + 4-phospho-L-aspartate
Other name(s): aspartokinase; AK; β-aspartokinase; aspartic kinase
Systematic name: ATP:L-aspartate 4-phosphotransferase
Comments: The enzyme from Escherichia coli is a multifunctional protein, which also catalyses the reaction of EC 1.1.1.3 homoserine dehydrogenase. This is also the case for two of the four isoenzymes in Arabidopsis thaliana. The equilibrium constant strongly favours the reaction from right to left, i.e. the non-physiological direction of reaction.
References:
1.  Black, S. Conversion of aspartic acid to homoserine. Methods Enzymol. 5 (1962) 820–827.
2.  Paulus, H. and Gray, E. Multivalent feedback inhibition of aspartokinase in Bacillus polymyxa. I. Kinetic studies. J. Biol. Chem. 242 (1967) 4980–4986. [PMID: 6058940]
3.  Starnes, W.L., Munk, P., Maul, S.B., Cunningham, G.N., Cox, D.J. and Shive, W. Threonine-sensitive aspartokinase-homoserine dehydrogenase complex, amino acid composition, molecular weight, and subunit composition of the complex. Biochemistry 11 (1972) 677–687. [PMID: 4551091]
4.  Véron, M., Falcoz-Kelly, F. and Cohen, G.N. The threonine-sensitive homoserine dehydrogenase and aspartokinase activities of Escherichia coli K12. The two catalytic activities are carried by two independent regions of the polypeptide chain. Eur. J. Biochem. 28 (1972) 520–527. [PMID: 4562990]
5.  Chassagnole, C., Rais, B., Quentin, E., Fell, D. A. and Mazat, J.-P. An integrated study of threonine-pathway enzyme kinetics in Escherichia coli. Biochem. J. 356 (2001) 415–423. [PMID: 11368768]
6.  Curien, G., Ravanel, S., Robert, M. and Dumas, R. Identification of six novel allosteric effectors of Arabidopsis thaliana aspartate kinase-homoserine dehydrogenase isoforms. J. Biol. Chem. 280 (2005) 41178–41183. [PMID: 16216875]
[EC 2.7.2.4 created 1961]
 
 
EC 2.7.4.14     
Accepted name: UMP/CMP kinase
Reaction: (1) ATP + (d)CMP = ADP + (d)CDP
(2) ATP + UMP = ADP + UDP
Other name(s): cytidylate kinase (misleading); deoxycytidylate kinase (misleading); CTP:CMP phosphotransferase (misleading); dCMP kinase (misleading); deoxycytidine monophosphokinase (misleading); UMP-CMP kinase; ATP:UMP-CMP phosphotransferase; pyrimidine nucleoside monophosphate kinase; uridine monophosphate-cytidine monophosphate phosphotransferase
Systematic name: ATP:(d)CMP/UMP phosphotransferase
Comments: This eukaryotic enzyme is a bifunctional enzyme that catalyses the phosphorylation of both CMP and UMP with similar efficiency. dCMP can also act as acceptor. Different from the monofunctional prokaryotic enzymes EC 2.7.4.25, (d)CMP kinase and EC 2.7.4.22, UMP kinase.
References:
1.  Hurwitz, J. The enzymatic incorporation of ribonucleotides into polydeoxynucleotide material. J. Biol. Chem. 234 (1959) 2351–2358. [PMID: 14405566]
2.  Ruffner, B.W., Jr. and Anderson, E.P. Adenosine triphosphate: uridine monophosphate-cytidine monophosphate phosphotransferase from Tetrahymena pyriformis. J. Biol. Chem. 244 (1969) 5994–6002. [PMID: 5350952]
3.  Scheffzek, K., Kliche, W., Wiesmuller, L. and Reinstein, J. Crystal structure of the complex of UMP/CMP kinase from Dictyostelium discoideum and the bisubstrate inhibitor P1-(5′-adenosyl) P5-(5′-uridyl) pentaphosphate (UP5A) and Mg2+ at 2.2 Å: implications for water-mediated specificity. Biochemistry 35 (1996) 9716–9727. [PMID: 8703943]
4.  Zhou, L., Lacroute, F. and Thornburg, R. Cloning, expression in Escherichia coli, and characterization of Arabidopsis thaliana UMP/CMP kinase. Plant Physiol. 117 (1998) 245–254. [PMID: 9576794]
5.  Van Rompay, A.R., Johansson, M. and Karlsson, A. Phosphorylation of deoxycytidine analog monophosphates by UMP-CMP kinase: molecular characterization of the human enzyme. Mol. Pharmacol. 56 (1999) 562–569. [PMID: 10462544]
[EC 2.7.4.14 created 1961 as EC 2.7.4.5, transferred 1972 to EC 2.7.4.14, modified 1980, modified 2011]
 
 
EC 2.7.4.27     
Accepted name: [pyruvate, phosphate dikinase]-phosphate phosphotransferase
Reaction: [pyruvate, phosphate dikinase] phosphate + phosphate = [pyruvate, phosphate dikinase] + diphosphate
Other name(s): PPDK regulatory protein (ambiguous); pyruvate, phosphate dikinase regulatory protein (ambiguous); bifunctional dikinase regulatory protein (ambiguous); PDRP1 (gene name)
Systematic name: [pyruvate, phosphate dikinase]-phosphate:phosphate phosphotransferase
Comments: The enzyme from the plants maize and Arabidopsis is bifunctional and also catalyses the phosphorylation of pyruvate, phosphate dikinase (EC 2.7.9.1), cf. EC 2.7.11.32, [pyruvate, phosphate dikinase] kinase [2-5].
References:
1.  Burnell, J.N. and Hatch, M.D. Regulation of C4 photosynthesis: identification of a catalytically important histidine residue and its role in the regulation of pyruvate,Pi dikinase. Arch. Biochem. Biophys. 231 (1984) 175–182. [PMID: 6326674]
2.  Burnell, J.N. and Hatch, M.D. Regulation of C4 photosynthesis: purification and properties of the protein catalyzing ADP-mediated inactivation and Pi-mediated activation of pyruvate,Pi dikinase. Arch. Biochem. Biophys. 237 (1985) 490–503. [PMID: 2983615]
3.  Chastain, C.J., Botschner, M., Harrington, G.E., Thompson, B.J., Mills, S.E., Sarath, G. and Chollet, R. Further analysis of maize C4 pyruvate,orthophosphate dikinase phosphorylation by its bifunctional regulatory protein using selective substitutions of the regulatory Thr-456 and catalytic His-458 residues. Arch. Biochem. Biophys. 375 (2000) 165–170. [PMID: 10683263]
4.  Burnell, J.N. and Chastain, C.J. Cloning and expression of maize-leaf pyruvate, Pi dikinase regulatory protein gene. Biochem. Biophys. Res. Commun. 345 (2006) 675–680. [PMID: 16696949]
5.  Chastain, C.J., Xu, W., Parsley, K., Sarath, G., Hibberd, J.M. and Chollet, R. The pyruvate, orthophosphate dikinase regulatory proteins of Arabidopsis possess a novel, unprecedented Ser/Thr protein kinase primary structure. Plant J. 53 (2008) 854–863. [PMID: 17996018]
[EC 2.7.4.27 created 2012]
 
 
EC 2.7.4.32     
Accepted name: farnesyl phosphate kinase
Reaction: CTP + (2E,6E)-farnesyl phosphate = CDP + (2E,6E)-farnesyl diphosphate
Systematic name: CTP:(2E,6E)-farnesyl-phosphate phosphotransferase
Comments: The enzyme, found in plants and animals, is specific for CTP as phosphate donor. It does not use farnesol as substrate (cf. EC 2.7.1.216, farnesol kinase).
References:
1.  Bentinger, M., Grunler, J., Peterson, E., Swiezewska, E. and Dallner, G. Phosphorylation of farnesol in rat liver microsomes: properties of farnesol kinase and farnesyl phosphate kinase. Arch. Biochem. Biophys. 353 (1998) 191–198. [PMID: 9606952]
2.  Fitzpatrick, A.H., Bhandari, J. and Crowell, D.N. Farnesol kinase is involved in farnesol metabolism, ABA signaling and flower development in Arabidopsis. Plant J. 66 (2011) 1078–1088. [PMID: 21395888]
[EC 2.7.4.32 created 2017]
 
 
EC 2.7.6.3     
Accepted name: 2-amino-4-hydroxy-6-hydroxymethyldihydropteridine diphosphokinase
Reaction: ATP + 6-hydroxymethyl-7,8-dihydropterin = AMP + 6-hydroxymethyl-7,8-dihydropterin diphosphate
Other name(s): 2-amino-4-hydroxy-6-hydroxymethyldihydropteridine pyrophosphokinase; H2-pteridine-CH2OH pyrophosphokinase; 7,8-dihydroxymethylpterin-pyrophosphokinase; HPPK; 7,8-dihydro-6-hydroxymethylpterin pyrophosphokinase; hydroxymethyldihydropteridine pyrophosphokinase; ATP:2-amino-4-hydroxy-6-hydroxymethyl-7,8-dihydropteridine 6′-diphosphotransferase
Systematic name: ATP:6-hydroxymethyl-7,8-dihydropterin 6′-diphosphotransferase
Comments: Binds 2 Mg2+ ions that are essential for activity [4]. The enzyme participates in the biosynthetic pathways for folate (in bacteria, plants, fungi, and some archaeal species, including the haloarchaea) and methanopterin (in some archaeal species such as the Archaeoglobi and Methanobacteria). The enzyme exists in varying types of multifunctional proteins in different organisms. The enzyme from the bacterium Streptococcus pneumoniae also harbours the activity of EC 4.1.2.25, dihydroneopterin aldolase [4], the enzyme from the plant Arabidopsis thaliana harbours the activity of EC 2.5.1.15, dihydropteroate synthase [7], while the enzyme from yeast Saccharomyces cerevisiae is trifunctional with both of the two above mentioned activities [6].
References:
1.  Shiota, T., Baugh, C.M., Jackson, R. and Dillard, R. The enzymatic synthesis of hydroxymethyldihydropteridine pyrophosphate and dihydrofolate. Biochemistry 8 (1969) 5022–5028. [PMID: 4312465]
2.  Richey, D.P. and Brown, G.M. The biosynthesis of folic acid. IX. Purification and properties of the enzymes required for the formation of dihydropteroic acid. J. Biol. Chem. 244 (1969) 1582–1592. [PMID: 4304228]
3.  Richey, D.P. and Brown, G.M. Hydroxymethyldihydropteridine pyrophosphokinase and dihydropteroate synthetase from Escherichia coli. Methods Enzymol. 18B (1971) 765–771.
4.  Lopez, P. and Lacks, S.A. A bifunctional protein in the folate biosynthetic pathway of Streptococcus pneumoniae with dihydroneopterin aldolase and hydroxymethyldihydropterin pyrophosphokinase activities. J. Bacteriol. 175 (1993) 2214–2220. [PMID: 8385663]
5.  Blaszczyk, J., Shi, G., Yan, H. and Ji, X. Catalytic center assembly of HPPK as revealed by the crystal structure of a ternary complex at 1.25 Å resolution. Structure 8 (2000) 1049–1058. [PMID: 11080626]
6.  Güldener, U., Koehler, G.J., Haussmann, C., Bacher, A., Kricke, J., Becher, D. and Hegemann, J.H. Characterization of the Saccharomyces cerevisiae Fol1 protein: starvation for C1 carrier induces pseudohyphal growth. Mol. Biol. Cell 15 (2004) 3811–3828. [PMID: 15169867]
7.  Storozhenko, S., Navarrete, O., Ravanel, S., De Brouwer, V., Chaerle, P., Zhang, G.F., Bastien, O., Lambert, W., Rebeille, F. and Van Der Straeten, D. Cytosolic hydroxymethyldihydropterin pyrophosphokinase/dihydropteroate synthase from Arabidopsis thaliana: a specific role in early development and stress response. J. Biol. Chem. 282 (2007) 10749–10761. [PMID: 17289662]
[EC 2.7.6.3 created 1972, modified 2015]
 
 
EC 2.7.6.5     
Accepted name: GTP diphosphokinase
Reaction: ATP + GTP = AMP + guanosine 3′-diphosphate 5′-triphosphate
Other name(s): stringent factor; guanosine 3′,5′-polyphosphate synthase; GTP pyrophosphokinase; ATP-GTP 3′-diphosphotransferase; guanosine 5′,3′-polyphosphate synthetase; (p)ppGpp synthetase I; (p)ppGpp synthetase II; guanosine pentaphosphate synthetase; GPSI; GPSII
Systematic name: ATP:GTP 3′-diphosphotransferase
Comments: GDP can also act as acceptor.
References:
1.  Fehr, S. and Richter, D. Stringent response of Bacillus stearothermophilus: evidence for the existence of two distinct guanosine 3′,5′-polyphosphate synthetases. J. Bacteriol. 145 (1981) 68–73. [PMID: 6161916]
2.  Sy, J. and Akers, H. Purification and properties of guanosine 5′,3′-polyphosphate synthetase from Bacillus brevis. Biochemistry 15 (1976) 4399–4403. [PMID: 184817]
[EC 2.7.6.5 created 1981]
 
 
EC 2.7.7.69     
Accepted name: GDP-L-galactose/GDP-D-glucose: hexose 1-phosphate guanylyltransferase
Reaction: (1) GDP-β-L-galactose + α-D-mannose 1-phosphate = β-L-galactose 1-phosphate + GDP-α-D-mannose
(2) GDP-α-D-glucose + α-D-mannose 1-phosphate = α-D-glucose 1-phosphate + GDP-α-D-mannose
Other name(s): VTC2; VTC5; GDP-L-galactose phosphorylase
Systematic name: GDP-β-L-galactose/GDP-α-D-glucose:hexose 1-phosphate guanylyltransferase
Comments: This plant enzyme catalyses the conversion of GDP-β-L-galactose and GDP-α-D-glucose to β-L-galactose 1-phosphate and α-D-glucose 1-phosphate, respectively. The enzyme can use inorganic phosphate as the co-substrate, but several hexose 1-phosphates, including α-D-mannose 1-phosphate, α-D-glucose 1-phosphate, and α-D-galactose 1-phosphate, are better guanylyl acceptors. The enzyme's activity on GDP-β-L-galactose is crucial for the biosynthesis of L-ascorbate.
References:
1.  Linster, C.L., Gomez, T.A., Christensen, K.C., Adler, L.N., Young, B.D., Brenner, C. and Clarke, S.G. Arabidopsis VTC2 encodes a GDP-L-galactose phosphorylase, the last unknown enzyme in the Smirnoff-Wheeler pathway to ascorbic acid in plants. J. Biol. Chem. 282 (2007) 18879–18885. [PMID: 17462988]
2.  Dowdle, J., Ishikawa, T., Gatzek, S., Rolinski, S. and Smirnoff, N. Two genes in Arabidopsis thaliana encoding GDP-L-galactose phosphorylase are required for ascorbate biosynthesis and seedling viability. Plant J. 52 (2007) 673–689. [PMID: 17877701]
3.  Wolucka, B.A. and Van Montagu, M. The VTC2 cycle and the de novo biosynthesis pathways for vitamin C in plants: an opinion. Phytochemistry 68 (2007) 2602–2613. [PMID: 17950389]
4.  Laing, W.A., Wright, M.A., Cooney, J. and Bulley, S.M. The missing step of the L-galactose pathway of ascorbate biosynthesis in plants, an L-galactose guanyltransferase, increases leaf ascorbate content. Proc. Natl. Acad. Sci. USA 104 (2007) 9534–9539. [PMID: 17485667]
5.  Linster, C.L., Adler, L.N., Webb, K., Christensen, K.C., Brenner, C. and Clarke, S.G. A second GDP-L-galactose phosphorylase in arabidopsis en route to vitamin C. Covalent intermediate and substrate requirements for the conserved reaction. J. Biol. Chem. 283 (2008) 18483–18492. [PMID: 18463094]
6.  Muller-Moule, P. An expression analysis of the ascorbate biosynthesis enzyme VTC2. Plant Mol. Biol. 68 (2008) 31–41. [PMID: 18516687]
[EC 2.7.7.69 created 2010, modified 2020]
 
 
EC 2.7.7.75     
Accepted name: molybdopterin adenylyltransferase
Reaction: ATP + molybdopterin = diphosphate + adenylyl-molybdopterin
Glossary: molybdopterin = H2Dtpp-mP = [(5aR,8R,9aR)-2-amino-4-oxo-6,7-bis(sulfanyl)-4,5,5a,8,9a,10-hexahydro-1H-pyrano[3,2-g]pteridin-8-yl]methyl dihydrogen phosphate
Other name(s): MogA; Cnx1 (ambiguous)
Systematic name: ATP:molybdopterin adenylyltransferase
Comments: Catalyses the activation of molybdopterin for molybdenum insertion. In eukaryotes, this reaction is catalysed by the C-terminal domain of a fusion protein that also includes molybdopterin molybdotransferase (EC 2.10.1.1). The reaction requires a divalent cation such as Mg2+ or Mn2+.
References:
1.  Nichols, J.D. and Rajagopalan, K.V. In vitro molybdenum ligation to molybdopterin using purified components. J. Biol. Chem. 280 (2005) 7817–7822. [PMID: 15632135]
2.  Kuper, J., Palmer, T., Mendel, R.R. and Schwarz, G. Mutations in the molybdenum cofactor biosynthetic protein Cnx1G from Arabidopsis thaliana define functions for molybdopterin binding, molybdenum insertion, and molybdenum cofactor stabilization. Proc. Natl. Acad. Sci. USA 97 (2000) 6475–6480. [PMID: 10823911]
3.  Llamas, A., Mendel, R.R. and Schwarz, G. Synthesis of adenylated molybdopterin: an essential step for molybdenum insertion. J. Biol. Chem. 279 (2004) 55241–55246. [PMID: 15504727]
[EC 2.7.7.75 created 2011]
 
 
EC 2.7.8.5     
Accepted name: CDP-diacylglycerol—glycerol-3-phosphate 1-phosphatidyltransferase
Reaction: CDP-diacylglycerol + sn-glycerol 3-phosphate = CMP + 1-(3-sn-phosphatidyl)-sn-glycerol 3-phosphate
Other name(s): glycerophosphate phosphatidyltransferase; 3-phosphatidyl-1′-glycerol-3′-phosphate synthase; CDPdiacylglycerol:glycerol-3-phosphate phosphatidyltransferase; cytidine 5′-diphospho-1,2-diacyl-sn-glycerol (CDP-diglyceride):sn-glycerol-3-phosphate phosphatidyltransferase; phosphatidylglycerophosphate synthase; phosphatidylglycerolphosphate synthase; PGP synthase; CDP-diacylglycerol-sn-glycerol-3-phosphate 3-phosphatidyltransferase; CDP-diacylglycerol:sn-glycero-3-phosphate phosphatidyltransferase; glycerol phosphate phosphatidyltransferase; glycerol 3-phosphate phosphatidyltransferase; phosphatidylglycerol phosphate synthase; phosphatidylglycerol phosphate synthetase; phosphatidylglycerophosphate synthetase; sn-glycerol-3-phosphate phosphatidyltransferase
Systematic name: CDP-diacylglycerol:sn-glycerol-3-phosphate 1-(3-sn-phosphatidyl)transferase
Comments: The enzyme catalyses the committed step in the biosynthesis of acidic phospholipids known by the common names phophatidylglycerols and cardiolipins.
References:
1.  Hirabayashi, T. Larson, T.J. and Dowhan, W. Membrane-associated phosphatidylglycerophosphate synthetase from Escherichia coli: Purification by substrate affinity chromatography on cytidine 5′-diphospho-1,2-diacyl-sn-glycerol sepharose. Biochemistry 15 (1976) 5205–5211. [PMID: 793612]
2.  Bleasdale, J.E. and Johnston, J.M. CMP-dependent incorporation of [14C]glycerol 3-phosphate into phosphatidylglycerol and phosphatidylglycerol phosphate by rabbit lung microsomes. Biochim. Biophys. Acta 710 (1982) 377–390. [PMID: 7074121]
3.  Dowhan, W. Phosphatidylglycerophosphate synthase from Escherichia coli. Methods Enzymol. 209 (1992) 313–321. [PMID: 1323047]
4.  Kawasaki, K., Kuge, O., Chang, S.C., Heacock, P.N., Rho, M., Suzuki, K., Nishijima, M. and Dowhan, W. Isolation of a chinese hamster ovary (CHO) cDNA encoding phosphatidylglycerophosphate (PGP) synthase, expression of which corrects the mitochondrial abnormalities of a PGP synthase-defective mutant of CHO-K1 cells. J. Biol. Chem. 274 (1999) 1828–1834. [PMID: 9880566]
5.  Muller, F. and Frentzen, M. Phosphatidylglycerophosphate synthases from Arabidopsis thaliana. FEBS Lett. 509 (2001) 298–302. [PMID: 11741606]
6.  Babiychuk, E., Muller, F., Eubel, H., Braun, H.P., Frentzen, M. and Kushnir, S. Arabidopsis phosphatidylglycerophosphate synthase 1 is essential for chloroplast differentiation, but is dispensable for mitochondrial function. Plant J. 33 (2003) 899–909. [PMID: 12609031]
[EC 2.7.8.5 created 1972, modified 1976, modified 2016]
 
 
EC 2.7.8.41     
Accepted name: cardiolipin synthase (CMP-forming)
Reaction: a CDP-diacylglycerol + a phosphatidylglycerol = a cardiolipin + CMP
Systematic name: CDP-diacylglycerol:phosphatidylglycerol diacylglycerolphosphotransferase (CMP-forming)
Comments: The eukaryotic enzyme is involved in the biosynthesis of the mitochondrial phospholipid cardiolipin. It requires divalent cations for activity.
References:
1.  Schlame, M. and Hostetler, K.Y. Solubilization, purification, and characterization of cardiolipin synthase from rat liver mitochondria. Demonstration of its phospholipid requirement. J. Biol. Chem. 266 (1991) 22398–22403. [PMID: 1657995]
2.  Nowicki, M., Muller, F. and Frentzen, M. Cardiolipin synthase of Arabidopsis thaliana. FEBS Lett. 579 (2005) 2161–2165. [PMID: 15811335]
3.  Houtkooper, R.H., Akbari, H., van Lenthe, H., Kulik, W., Wanders, R.J., Frentzen, M. and Vaz, F.M. Identification and characterization of human cardiolipin synthase. FEBS Lett. 580 (2006) 3059–3064. [PMID: 16678169]
4.  Sandoval-Calderon, M., Geiger, O., Guan, Z., Barona-Gomez, F. and Sohlenkamp, C. A eukaryote-like cardiolipin synthase is present in Streptomyces coelicolor and in most actinobacteria. J. Biol. Chem. 284 (2009) 17383–17390. [PMID: 19439403]
[EC 2.7.8.41 created 2014]
 
 
EC 2.7.9.5     
Accepted name: phosphoglucan, water dikinase
Reaction: ATP + [phospho-α-glucan] + H2O = AMP + O-phospho-[phospho-α-glucan] + phosphate
Other name(s): PWD; OK1
Systematic name: ATP:phospho-α-glucan, water phosphotransferase
Comments: The enzyme phosphorylates granular starch that has previously been phosphorylated by EC 2.7.9.4, α-glucan, water dikinase; there is no activity with unphosphorylated glucans. It transfers the β-phosphate of ATP to the phosphoglucan, whereas the γ-phosphate is transferred to water [1]. In contrast to EC 2.7.9.4, which phosphorylates glucose groups in glucans on O-6, this enzyme phosphorylates glucose groups in phosphorylated starch on O-3 [2]. The protein phosphorylates itself with the β-phosphate of ATP, which is then transferred to the glucan [1].
References:
1.  Kötting, O., Pusch, K., Tiessen, A., Geigenberger, P., Steup, M. and Ritte, G. Identification of a novel enzyme required for starch metabolism in Arabidopsis leaves. The phosphoglucan, water dikinase. Plant Physiol. 137 (2005) 242–252. [PMID: 15618411]
2.  Ritte, G., Heydenreich, M., Mahlow, S., Haebel, S., Kötting, O. and Steup, M. Phosphorylation of C6- and C3-positions of glucosyl residues in starch is catalysed by distinct dikinases. FEBS Lett. 580 (2006) 4872–4876. [PMID: 16914145]
[EC 2.7.9.5 created 2005]
 
 
EC 2.7.11.1     
Accepted name: non-specific serine/threonine protein kinase
Reaction: ATP + a protein = ADP + a phosphoprotein
Other name(s): A-kinase; AP50 kinase; ATP-protein transphosphorylase; calcium-dependent protein kinase C; calcium/phospholipid-dependent protein kinase; cAMP-dependent protein kinase; cAMP-dependent protein kinase A; casein kinase; casein kinase (phosphorylating); casein kinase 2; casein kinase I; casein kinase II; cGMP-dependent protein kinase; CK-2; CKI; CKII; cyclic AMP-dependent protein kinase; cyclic AMP-dependent protein kinase A; cyclic monophosphate-dependent protein kinase; cyclic nucleotide-dependent protein kinase; cyclin-dependent kinase; cytidine 3′,5′-cyclic monophosphate-responsive protein kinase; dsk1; glycogen synthase a kinase; glycogen synthase kinase; HIPK2; Hpr kinase; hydroxyalkyl-protein kinase; hydroxyalkyl-protein kinase; M phase-specific cdc2 kinase; mitogen-activated S6 kinase; p82 kinase; phosphorylase b kinase kinase; PKA; protein glutamyl kinase; protein kinase (phosphorylating); protein kinase A; protein kinase CK2; protein kinase p58; protein phosphokinase; protein serine kinase; protein serine-threonine kinase; protein-aspartyl kinase; protein-cysteine kinase; protein-serine kinase; Prp4 protein kinase; Raf kinase; Raf-1; ribosomal protein S6 kinase II; ribosomal S6 protein kinase; serine kinase; serine protein kinase; serine-specific protein kinase; serine(threonine) protein kinase; serine/threonine protein kinase; STK32; T-antigen kinase; threonine-specific protein kinase; twitchin kinase; type-2 casein kinase; βIIPKC; ε PKC; Wee 1-like kinase; Wee-kinase; WEE1Hu
Systematic name: ATP:protein phosphotransferase (non-specific)
Comments: This is a heterogeneous group of serine/threonine protein kinases that do not have an activating compound and are either non-specific or their specificity has not been analysed to date.
References:
1.  Damuni, Z. and Reed, L.J. Purification and properties of a protamine kinase and a type II casein kinase from bovine kidney mitochondria. Arch. Biochem. Biophys. 262 (1988) 574–584. [PMID: 2835010]
2.  Baggio, B., Pinna, L.A., Moret, V. and Siliprandi, N. A simple procedure for the purification of rat liver phosvitin kinase. Biochim. Biophys. Acta 212 (1970) 515–517. [PMID: 5456997]
3.  Jergil, B. and Dixon, G.H. Protamine kinase from rainbow trout testis. Partial purification and characterization. J. Biol. Chem. 245 (1970) 425–434. [PMID: 4312674]
4.  Langan, T.A. Action of adenosine 3′,5′-monophosphate-dependent histone kinase in vivo. J. Biol. Chem. 244 (1969) 5763–5765. [PMID: 4310608]
5.  Takeuchi, M. and Yanagida, M. A mitotic role for a novel fission yeast protein kinase dsk1 with cell cycle stage dependent phosphorylation and localization. Mol. Biol. Cell 4 (1993) 247–260. [PMID: 8485317]
6.  Gross, T., Lutzelberger, M., Weigmann, H., Klingenhoff, A., Shenoy, S. and Kaufer, N.F. Functional analysis of the fission yeast Prp4 protein kinase involved in pre-mRNA splicing and isolation of a putative mammalian homologue. Nucleic Acids Res. 25 (1997) 1028–1035. [PMID: 9102632]
7.  Wang, Y., Hofmann, T.G., Runkel, L., Haaf, T., Schaller, H., Debatin, K. and Hug, H. Isolation and characterization of cDNAs for the protein kinase HIPK2. Biochim. Biophys. Acta 1518 (2001) 168–172. [PMID: 11267674]
[EC 2.7.11.1 created 2005 (EC 2.7.1.37 part-incorporated 2005]
 
 
EC 2.7.11.13     
Accepted name: protein kinase C
Reaction: ATP + a protein = ADP + a phosphoprotein
Other name(s): calcium-dependent protein kinase C; calcium-independent protein kinase C; calcium/phospholipid dependent protein kinase; cPKCα; cPKCβ; cPKCγ; nPKCδ; nPKCε; nPKC; nPKC; PKC; PKCα; PKCβ; PKCγ; PKCδ; PKCε; PKCζ; Pkc1p; protein kinase Cε; STK24
Systematic name: ATP:protein phosphotransferase (diacylglycerol-dependent)
Comments: A family of serine- and threonine-specific protein kinases that depend on lipids for activity. They can be activated by calcium but have a requirement for the second messenger diacylglycerol. Members of this group of enzymes phosphorylate a wide variety of protein targets and are known to be involved in diverse cell-signalling pathways. Members of the protein kinase C family also serve as major receptors for phorbol esters, a class of tumour promoters.
References:
1.  Jaken, S. Protein kinase C and tumor promoters. Curr. Opin. Cell 2 (1990) 192–197. [PMID: 2194521]
2.  Parekh, D.B., Ziegler, W. and Parker, P.J. Multiple pathways control protein kinase C phosphorylation. EMBO J. 19 (2000) 496–503. [PMID: 10675318]
3.  Valledor, A.F., Xaus, J., Comalada, M., Soler, C. and Celada, A. Protein kinase Cepsilon is required for the induction of mitogen-activated protein kinase phosphatase-1 in lipopolysaccharide-stimulated macrophages. J. Immunol. 164 (2000) 29–37. [PMID: 10604989]
4.  Lendenfeld, T. and Kubicek, C.P. Characterization and properties of protein kinase C from the filamentous fungus Trichoderma reesei. Biochem. J. 330 (1998) 689–694. [PMID: 9480876]
5.  Brooks, S.P. and Storey, K.B. Protein kinase C from rainbow trout brain: identification and characterization of three isozymes. Biochem. Mol. Biol. Int. 44 (1998) 259–267. [PMID: 9530509]
[EC 2.7.11.13 created 2005 (EC 2.7.1.37 part-incorporated 2005)]
 
 
EC 2.7.11.14     
Accepted name: rhodopsin kinase
Reaction: ATP + rhodopsin = ADP + phosphorhodopsin
Other name(s): cone opsin kinase; G-protein-coupled receptor kinase 1; GPCR kinase 1; GRK1; GRK7; opsin kinase; opsin kinase (phosphorylating); rhodopsin kinase (phosphorylating); RK; STK14
Systematic name: ATP:rhodopsin phosphotransferase
Comments: Requires G-protein for activation and therefore belongs to the family of G-protein-dependent receptor kinases (GRKs). Acts on the bleached or activated form of rhodopsin; also phosphorylates the β-adrenergic receptor, but more slowly. Does not act on casein, histones or phosphvitin. Inhibited by Zn2+ and digitonin (cf. EC 2.7.11.15, β-adrenergic-receptor kinase and EC 2.7.11.16, G-protein-coupled receptor kinase).
References:
1.  Benovic, J.L., Mayor, F., Jr., Somers, R.L., Caron, M.G. and Lefkowitz, R.J. Light-dependent phosphorylation of rhodopsin by β-adrenergic receptor kinase. Nature 321 (1986) 869–872. [PMID: 3014340]
2.  Shichi, H. and Somers, R.L. Light-dependent phosphorylation of rhodopsin. Purification and properties of rhodopsin kinase. J. Biol. Chem. 253 (1978) 7040–7046. [PMID: 690139]
3.  Palczewski, K., McDowell, J.H. and Hargrave, P.A. Purification and characterization of rhodopsin kinase. J. Biol. Chem. 263 (1988) 14067–14073. [PMID: 2844754]
4.  Weller, M., Virmaux, N. and Mandel, P. Light-stimulated phosphorylation of rhodopsin in the retina: the presence of a protein kinase that is specific for photobleached rhodopsin. Proc. Natl. Acad. Sci. USA 72 (1975) 381–385. [PMID: 164024]
5.  Cha, K., Bruel, C., Inglese, J. and Khorana, H.G. Rhodopsin kinase: expression in baculovirus-infected insect cells, and characterization of post-translational modifications. Proc. Natl. Acad. Sci. USA 94 (1997) 10577–10582. [PMID: 9380677]
6.  Khani, S.C., Abitbol, M., Yamamoto, S., Maravic-Magovcevic, I. and Dryja, T.P. Characterization and chromosomal localization of the gene for human rhodopsin kinase. Genomics 35 (1996) 571–576. [PMID: 8812493]
7.  Chen, C.K., Zhang, K., Church-Kopish, J., Huang, W., Zhang, H., Chen, Y.J., Frederick, J.M. and Baehr, W. Characterization of human GRK7 as a potential cone opsin kinase. Mol. Vis. 7 (2001) 305–313. [PMID: 11754336]
8.  Willets, J.M., Challiss, R.A. and Nahorski, S.R. Non-visual GRKs: are we seeing the whole picture? Trends Pharmacol. Sci. 24 (2003) 626–633. [PMID: 14654303]
[EC 2.7.11.14 created 1989 as EC 2.7.1.125 (EC 2.7.1.97 created 1978, incorporated 1992), transferred 2005 to EC 2.7.11.14]
 
 
EC 2.7.11.15     
Accepted name: β-adrenergic-receptor kinase
Reaction: ATP + [β-adrenergic receptor] = ADP + phospho-[β-adrenergic receptor]
Other name(s): ATP:β-adrenergic-receptor phosphotransferase; [β-adrenergic-receptor] kinase; β-adrenergic receptor-specific kinase; β-AR kinase; β-ARK; β-ARK 1; β-ARK 2; β-receptor kinase; GRK2; GRK3; β-adrenergic-receptor kinase (phosphorylating); β2ARK; βARK1; β-adrenoceptor kinase; β-adrenoceptor kinase 1; β-adrenoceptor kinase 2; ADRBK1; BARK1; adrenergic receptor kinase; STK15
Systematic name: ATP:[β-adrenergic receptor] phosphotransferase
Comments: Requires G-protein for activation and therefore belongs to the family of G-protein-dependent receptor kinases (GRKs). Acts on the agonist-occupied form of the receptor; also phosphorylates rhodopsin, but more slowly. Does not act on casein or histones. The enzyme is inhibited by Zn2+ and digitonin but is unaffected by cyclic-AMP (cf. EC 2.7.11.14, rhodopsin kinase and EC 2.7.11.16, G-protein-coupled receptor kinase).
References:
1.  Benovic, J.L., Mayor, F., Jr., Staniszewski, C., Lefkowitz, R.J. and Caron, M.G. Purification and characterization of the β-adrenergic receptor kinase. J. Biol. Chem. 262 (1987) 9026–9032. [PMID: 3036840]
2.  Kim, C.M., Dion, S.B., Onorato, J.J. and Benovic, J.L. Expression and characterization of two β-adrenergic receptor kinase isoforms using the baculovirus expression system. Receptor 3 (1993) 39–55. [PMID: 8394172]
3.  Laugwitz, K.L., Kronsbein, K., Schmitt, M., Hoffmann, K., Seyfarth, M., Schomig, A. and Ungerer, M. Characterization and inhibition of β-adrenergic receptor kinase in intact myocytes. Cardiovasc Res 35 (1997) 324–333. [PMID: 9349395]
4.  Ferguson, S.S., Menard, L., Barak, L.S., Koch, W.J., Colapietro, A.M. and Caron, M.G. Role of phosphorylation in agonist-promoted β2-adrenergic receptor sequestration. Rescue of a sequestration-defective mutant receptor by betaARK1. J. Biol. Chem. 270 (1995) 24782–24789. [PMID: 7559596]
5.  Willets, J.M., Challiss, R.A. and Nahorski, S.R. Non-visual GRKs: are we seeing the whole picture? Trends Pharmacol. Sci. 24 (2003) 626–633. [PMID: 14654303]
[EC 2.7.11.15 created 1989 as EC 2.7.1.126, transferred 2005 to EC 2.7.11.15]
 
 
EC 2.7.11.16     
Accepted name: G-protein-coupled receptor kinase
Reaction: ATP + [G-protein-coupled receptor] = ADP + [G-protein-coupled receptor] phosphate
Other name(s): G protein-coupled receptor kinase; GPCR kinase; GPCRK; GRK4; GRK5; GRK6; STK16
Systematic name: ATP:[G-protein-coupled receptor] phosphotransferase
Comments: Requires G-protein for activation and therefore belongs to the family of G-protein-dependent receptor kinases (GRKs). All members of this enzyme subfamily possess a highly conserved binding site for 1-phosphatidylinositol 4,5-bisphosphate. (cf. EC 2.7.11.14, rhodopsin kinase and EC 2.7.11.15, β-adrenergic-receptor kinase).
References:
1.  Kunapuli, P., Onorato, J.J., Hosey, M.M. and Benovic, J.L. Expression, purification, and characterization of the G protein-coupled receptor kinase GRK5. J. Biol. Chem. 269 (1994) 1099–1105. [PMID: 8288567]
2.  Premont, R.T., Koch, W.J., Inglese, J. and Lefkowitz, R.J. Identification, purification, and characterization of GRK5, a member of the family of G protein-coupled receptor kinases. J. Biol. Chem. 269 (1994) 6832–6841. [PMID: 8120045]
3.  Willets, J.M., Challiss, R.A. and Nahorski, S.R. Non-visual GRKs: are we seeing the whole picture? Trends Pharmacol. Sci. 24 (2003) 626–633. [PMID: 14654303]
[EC 2.7.11.16 created 2005]
 
 
EC 2.7.11.17     
Accepted name: Ca2+/calmodulin-dependent protein kinase
Reaction: ATP + a protein = ADP + a phosphoprotein
Other name(s): ATP:caldesmon O-phosphotransferase; caldesmon kinase; caldesmon kinase (phosphorylating); Ca2+/calmodulin-dependent microtubule-associated protein 2 kinase; Ca2+/calmodulin-dependent protein kinase 1; Ca2+/calmodulin-dependent protein kinase II; Ca2+/calmodulin-dependent protein kinase IV; Ca2+/calmodulin-dependent protein kinase kinase; Ca2+/calmodulin-dependent protein kinase kinase β; calmodulin-dependent kinase II; CaM kinase; CaM kinase II; CAM PKII; CaM-regulated serine/threonine kinase; CaMKI; CaMKII; CaMKIV; CaMKKα; CaMKKβ; microtubule-associated protein 2 kinase; STK20
Systematic name: ATP:protein phosphotransferase (Ca2+/calmodulin-dependent)
Comments: Requires calmodulin and Ca2+ for activity. A wide range of proteins can act as acceptor, including vimentin, synapsin, glycogen synthase, myosin light chains and the microtubule-associated tau protein. Not identical with EC 2.7.11.18 (myosin-light-chain kinase) or EC 2.7.11.26 (tau-protein kinase).
References:
1.  Adlersberg, M., Liu, K.P., Hsiung, S.C., Ehrlich, Y. and Tamir, H. A Ca2+-dependent protein kinase activity associated with serotonin binding protein. J. Neurochem. 49 (1987) 1105–1115. [PMID: 3040904]
2.  Baudier, J. and Cole, R.D. Phosphorylation of tau proteins to a state like that in Alzheimer's brain is catalyzed by a calcium/calmodulin-dependent kinase and modulated by phospholipids. J. Biol. Chem. 262 (1987) 17577–17583. [PMID: 3121601]
3.  Schulman, H., Kuret, J., Jefferson, A.B., Nose, P.S. and Spitzer, K.H. Ca2+/calmodulin-dependent microtubule-associated protein 2 kinase: broad substrate specificity and multifunctional potential in diverse tissues. Biochemistry 24 (1985) 5320–5327. [PMID: 4074698]
4.  Anderson, K.A., Means, R.L., Huang, Q.H., Kemp, B.E., Goldstein, E.G., Selbert, M.A., Edelman, A.M., Fremeau, R.T. and Means, A.R. Components of a calmodulin-dependent protein kinase cascade. Molecular cloning, functional characterization and cellular localization of Ca2+/calmodulin-dependent protein kinase kinase beta. J. Biol. Chem. 273 (1998) 31880–31889. [PMID: 9822657]
5.  Matsushita, M. and Nairn, A.C. Characterization of the mechanism of regulation of Ca2+/ calmodulin-dependent protein kinase I by calmodulin and by Ca2+/calmodulin-dependent protein kinase kinase. J. Biol. Chem. 273 (1998) 21473–21481. [PMID: 9705275]
6.  Ohmstede, C.A., Jensen, K.F. and Sahyoun, N.E. Ca2+/calmodulin-dependent protein kinase enriched in cerebellar granule cells. Identification of a novel neuronal calmodulin-dependent protein kinase. J. Biol. Chem. 264 (1989) 5866–5875. [PMID: 2538431]
7.  Rieker, J.P., Swanljung-Collins, H. and Collins, J.H. Purification and characterization of a calmodulin-dependent myosin heavy chain kinase from intestinal brush border. J. Biol. Chem. 262 (1987) 15262–15268. [PMID: 2822719]
8.  Iwasa, T., Inoue, N., Fukunaga, K., Isobe, T., Okuyama, T. and Miyamoto, E. Purification and characterization of a multifunctional calmodulin-dependent protein kinase from canine myocardial cytosol. Arch. Biochem. Biophys. 248 (1986) 21–29. [PMID: 3089163]
9.  Gomes, A.V., Barnes, J.A. and Vogel, H.J. Spectroscopic characterization of the interaction between calmodulin-dependent protein kinase I and calmodulin. Arch. Biochem. Biophys. 379 (2000) 28–36. [PMID: 10864438]
10.  Mal, T.K., Skrynnikov, N.R., Yap, K.L., Kay, L.E. and Ikura, M. Detecting protein kinase recognition modes of calmodulin by residual dipolar couplings in solution NMR. Biochemistry 41 (2002) 12899–12906. [PMID: 12390014]
11.  Ngai, P.K. and Walsh, M.P. Inhibition of smooth muscle actin-activated myosin Mg2+-ATPase activity by caldesmon. J. Biol. Chem. 259 (1984) 13656–13659. [PMID: 6150036]
12.  Ikebe, M., Reardon, S., Scott-Woo, G.C., Zhou, Z. and Koda, Y. Purification and characterization of calmodulin-dependent multifunctional protein kinase from smooth muscle: isolation of caldesmon kinase. Biochemistry 29 (1990) 11242–11248. [PMID: 2176896]
[EC 2.7.11.17 created 1989 as EC 2.7.1.123, transferred 2005 to EC 2.7.11.17 (EC 2.7.1.120 incorporated 2005)]
 
 
EC 2.7.11.32     
Accepted name: [pyruvate, phosphate dikinase] kinase
Reaction: ADP + [pyruvate, phosphate dikinase] = AMP + [pyruvate, phosphate dikinase] phosphate
Other name(s): PPDK regulatory protein (ambiguous); pyruvate; phosphate dikinase regulatory protein (ambiguous); bifunctional dikinase regulatory protein (ambiguous)
Systematic name: ADP:[pyruvate, phosphate dikinase] phosphotransferase
Comments: The enzymes from the plants Zea mays (maize) and Arabidopsis thaliana are bifunctional and catalyse both the phosphorylation and dephosphorylation of EC 2.7.9.1 (pyruvate, phosphate dikinase). cf. EC 2.7.4.27, [pyruvate, phosphate dikinase]-phosphate phosphotransferase [2-5]. The enzyme is specific for a reaction intermediate form of EC 2.7.9.1, and phosphorylates a threonine located adjacent to the catalytic histidine. The phosphorylation only takes place if the histidine is already phosphorylated [3-5].
References:
1.  Burnell, J.N. and Hatch, M.D. Regulation of C4 photosynthesis: identification of a catalytically important histidine residue and its role in the regulation of pyruvate,Pi dikinase. Arch. Biochem. Biophys. 231 (1984) 175–182. [PMID: 6326674]
2.  Burnell, J.N. and Hatch, M.D. Regulation of C4 photosynthesis: purification and properties of the protein catalyzing ADP-mediated inactivation and Pi-mediated activation of pyruvate,Pi dikinase. Arch. Biochem. Biophys. 237 (1985) 490–503. [PMID: 2983615]
3.  Chastain, C.J., Botschner, M., Harrington, G.E., Thompson, B.J., Mills, S.E., Sarath, G. and Chollet, R. Further analysis of maize C4 pyruvate,orthophosphate dikinase phosphorylation by its bifunctional regulatory protein using selective substitutions of the regulatory Thr-456 and catalytic His-458 residues. Arch. Biochem. Biophys. 375 (2000) 165–170. [PMID: 10683263]
4.  Burnell, J.N. and Chastain, C.J. Cloning and expression of maize-leaf pyruvate, Pi dikinase regulatory protein gene. Biochem. Biophys. Res. Commun. 345 (2006) 675–680. [PMID: 16696949]
5.  Chastain, C.J., Xu, W., Parsley, K., Sarath, G., Hibberd, J.M. and Chollet, R. The pyruvate, orthophosphate dikinase regulatory proteins of Arabidopsis possess a novel, unprecedented Ser/Thr protein kinase primary structure. Plant J. 53 (2008) 854–863. [PMID: 17996018]
[EC 2.7.11.32 created 2012]
 
 
EC 2.7.12.1     
Accepted name: dual-specificity kinase
Reaction: ATP + a protein = ADP + a phosphoprotein
Other name(s): ADK1; Arabidopsis dual specificity kinase 1; CLK1; dDYRK2; Mps1p
Systematic name: ATP:protein phosphotransferase (Ser/Thr- and Tyr-phosphorylating)
Comments: This family of enzymes can phosphorylate both Ser/Thr and Tyr residues.
References:
1.  Ali, N., Halfter, U. and Chua, N.H. Cloning and biochemical characterization of a plant protein kinase that phosphorylates serine, threonine, and tyrosine. J. Biol. Chem. 269 (1994) 31626–31629. [PMID: 7527390]
2.  Lauze, E., Stoelcker, B., Luca, F.C., Weiss, E., Schutz, A.R. and Winey, M. Yeast spindle pole body duplication gene MPS1 encodes an essential dual specificity protein kinase. EMBO J. 14 (1995) 1655–1663. [PMID: 7737118]
3.  Menegay, H.J., Myers, M.P., Moeslein, F.M. and Landreth, G.E. Biochemical characterization and localization of the dual specificity kinase CLK1. J. Cell Sci. 113 (2000) 3241–3253. [PMID: 10954422]
4.  Lochhead, P.A., Sibbet, G., Kinstrie, R., Cleghon, T., Rylatt, M., Morrison, D.K. and Cleghon, V. dDYRK2: a novel dual-specificity tyrosine-phosphorylation-regulated kinase in Drosophila. Biochem. J. 374 (2003) 381–391. [PMID: 12786602]
[EC 2.7.12.1 created 2005 (EC 2.7.1.37 part-incorporated 2005)]
 
 
EC 2.8.1.9     
Accepted name: molybdenum cofactor sulfurtransferase
Reaction: molybdenum cofactor + L-cysteine + reduced acceptor + 2 H+ = thio-molybdenum cofactor + L-alanine + H2O + oxidized acceptor
Glossary: molybdenum cofactor = MoCo = MoO2(OH)Dtpp-mP = {[(5aR,8R,9aR)-2-amino-4-oxo-6,7-bis(sulfanyl-κS)-1,5,5a,8,9a,10-hexahydro-4H-pyrano[3,2-g]pteridin-8-yl]methyl dihydrogenato(2-) phosphate}(dioxo)molybdate
Other name(s): molybdenum cofactor sulfurase; ABA3; HMCS; MoCo sulfurase; MoCo sulfurtransferase
Systematic name: L-cysteine:molybdenum cofactor sulfurtransferase
Comments: Contains pyridoxal phosphate. Replaces the equatorial oxo ligand of the molybdenum by sulfur via an enzyme-bound persulfide. The reaction occurs in prokaryotes and eukaryotes but MoCo sulfurtransferases are only found in eukaryotes. In prokaryotes the reaction is catalysed by two enzymes: cysteine desulfurase (EC 2.8.1.7), which is homologous to the N-terminus of eukaryotic MoCo sulfurtransferases, and a molybdo-enzyme specific chaperone which binds the MoCo and acts as an adapter protein.
References:
1.  Bittner, F., Oreb, M. and Mendel, R.R. ABA3 is a molybdenum cofactor sulfurase required for activation of aldehyde oxidase and xanthine dehydrogenase in Arabidopsis thaliana. J. Biol. Chem. 276 (2001) 40381–40384. [PMID: 11553608]
2.  Heidenreich, T., Wollers, S., Mendel, R.R. and Bittner, F. Characterization of the NifS-like domain of ABA3 from Arabidopsis thaliana provides insight into the mechanism of molybdenum cofactor sulfuration. J. Biol. Chem. 280 (2005) 4213–4218. [PMID: 15561708]
3.  Wollers, S., Heidenreich, T., Zarepour, M., Zachmann, D., Kraft, C., Zhao, Y., Mendel, R.R. and Bittner, F. Binding of sulfurated molybdenum cofactor to the C-terminal domain of ABA3 from Arabidopsis thaliana provides insight into the mechanism of molybdenum cofactor sulfuration. J. Biol. Chem. 283 (2008) 9642–9650. [PMID: 18258600]
[EC 2.8.1.9 created 2011, modified 2015]
 
 
EC 2.8.2.24     
Accepted name: aromatic desulfoglucosinolate sulfotransferase
Reaction: (1) 3′-phosphoadenylyl sulfate + desulfoglucotropeolin = adenosine 3′,5′-bisphosphate + glucotropeolin
(2) 3′-phosphoadenylyl sulfate + indolylmethyl-desulfoglucosinolate = adenosine 3′,5′-bisphosphate + glucobrassicin
Glossary: 3′-phosphoadenylyl sulfate = PAPS
Other name(s): desulfoglucosinolate sulfotransferase (ambiguous); PAPS-desulfoglucosinolate sulfotransferase (ambiguous); 3′-phosphoadenosine-5′-phosphosulfate:desulfoglucosinolate sulfotransferase (ambiguous); 3′-phosphoadenylyl-sulfate:aromatic desulfoglucosinolate sulfotransferase
Systematic name: 3′-phosphoadenylyl-sulfate:aromatic desulfoglucosinolate sulfonotransferase
Comments: This enzyme, characterized from cruciferous plants, catalyses the last step in the biosynthesis of tryptophan- and phenylalanine-derived glucosinolates. cf. EC 2.8.2.38, aliphatic desulfoglucosinolate sulfotransferase.
References:
1.  Jain, J.C., Reed, D.W., Groot Wassink, J.W.D. and Underhill, E.W. A radioassay of enzymes catalyzing the glucosylation and sulfation steps of glucosinolate biosynthesis in Brassica species. Anal. Biochem. 178 (1989) 137–140. [PMID: 2524977]
2.  Klein, M., Reichelt, M., Gershenzon, J. and Papenbrock, J. The three desulfoglucosinolate sulfotransferase proteins in Arabidopsis have different substrate specificities and are differentially expressed. FEBS J. 273 (2006) 122–136. [PMID: 16367753]
3.  Klein, M. and Papenbrock, J. Kinetics and substrate specificities of desulfo-glucosinolate sulfotransferases in Arabidopsis thaliana. Physiol. Plant. 135 (2009) 140–149. [PMID: 19077143]
[EC 2.8.2.24 created 1992, modified 2017]
 
 
EC 2.8.2.38     
Accepted name: aliphatic desulfoglucosinolate sulfotransferase
Reaction: 3′-phosphoadenylyl sulfate + an aliphatic desulfoglucosinolate = adenosine 3′,5′-bisphosphate + an aliphatic glucosinolate
Other name(s): SOT17 (gene name); SOT18 (gene name); 3′-phosphoadenylyl-sulfate:aliphatic desulfoglucosinolate sulfotransferase
Systematic name: 3′-phosphoadenylyl-sulfate:aliphatic desulfoglucosinolate sulfonotransferase
Comments: The enzyme catalyses the last step in the biosynthesis of aliphatic glucosinolate core structures. cf. EC 2.8.2.24, aromatic desulfoglucosinolate sulfotransferase.
References:
1.  Piotrowski, M., Schemenewitz, A., Lopukhina, A., Muller, A., Janowitz, T., Weiler, E.W. and Oecking, C. Desulfoglucosinolate sulfotransferases from Arabidopsis thaliana catalyze the final step in the biosynthesis of the glucosinolate core structure. J. Biol. Chem. 279 (2004) 50717–50725. [PMID: 15358770]
2.  Klein, M., Reichelt, M., Gershenzon, J. and Papenbrock, J. The three desulfoglucosinolate sulfotransferase proteins in Arabidopsis have different substrate specificities and are differentially expressed. FEBS J. 273 (2006) 122–136. [PMID: 16367753]
3.  Klein, M. and Papenbrock, J. Kinetics and substrate specificities of desulfo-glucosinolate sulfotransferases in Arabidopsis thaliana. Physiol. Plant. 135 (2009) 140–149. [PMID: 19077143]
[EC 2.8.2.38 created 2017]
 
 
EC 2.8.2.39     
Accepted name: hydroxyjasmonate sulfotransferase
Reaction: 3′-phosphoadenylyl-sulfate + 12-hydroxyjasmonate = adenosine 3′,5′-bisphosphate + 12-sulfooxyjasmonate
Glossary: 12-hydroxyjasmonate = {(1R,2R)-2-[(2E)-5-hydroxypent-2-enyl]-3-oxocyclopentyl}acetate
Other name(s): ST2A (gene name); 3′-phosphoadenylyl-sulfate:12-hydroxyjasmonate sulfotransferase
Systematic name: 3′-phosphoadenylyl-sulfate:12-hydroxyjasmonate sulfonotransferase
Comments: The enzyme, charaterized from the plant Arabidopsis thaliana, also acts on 11-hydroxyjasmonate.
References:
1.  Gidda, S.K., Miersch, O., Levitin, A., Schmidt, J., Wasternack, C. and Varin, L. Biochemical and molecular characterization of a hydroxyjasmonate sulfotransferase from Arabidopsis thaliana. J. Biol. Chem. 278 (2003) 17895–17900. [PMID: 12637544]
[EC 2.8.2.39 created 2017]
 
 
EC 3.1.1.3     
Accepted name: triacylglycerol lipase
Reaction: triacylglycerol + H2O = diacylglycerol + a carboxylate
Other name(s): lipase (ambiguous); butyrinase; tributyrinase; Tween hydrolase; steapsin; triacetinase; tributyrin esterase; Tweenase; amno N-AP; Takedo 1969-4-9; Meito MY 30; Tweenesterase; GA 56; capalase L; triglyceride hydrolase; triolein hydrolase; tween-hydrolyzing esterase; amano CE; cacordase; triglyceridase; triacylglycerol ester hydrolase; amano P; amano AP; PPL; glycerol-ester hydrolase; GEH; meito Sangyo OF lipase; hepatic lipase; lipazin; post-heparin plasma protamine-resistant lipase; salt-resistant post-heparin lipase; heparin releasable hepatic lipase; amano CES; amano B; tributyrase; triglyceride lipase; liver lipase; hepatic monoacylglycerol acyltransferase; PNLIP (gene name); LIPF (gene name)
Systematic name: triacylglycerol acylhydrolase
Comments: The enzyme is found in diverse organisms including animals, plants, fungi, and bacteria. It hydrolyses triglycerides into diglycerides and subsequently into monoglycerides and free fatty acids. The enzyme is highly soluble in water and acts at the surface of oil droplets. Access to the active site is controlled by the opening of a lid, which, when closed, hides the hydrophobic surface that surrounds the active site. The lid opens when the enzyme contacts an oil-water interface (interfacial activation). The pancreatic enzyme requires a protein cofactor, namely colipase, to counteract the inhibitory effects of bile salts.
References:
1.  Singer, T.P. and Hofstee, B.H.J. Studies on wheat germ lipase. I. Methods of estimation, purification and general properties of the enzyme. Arch. Biochem. 18 (1948) 229–243. [PMID: 18875045]
2.  Singer, T.P. and Hofstee, B.H.J. Studies on wheat germ lipase. II. Kinetics. Arch. Biochem. 18 (1948) 245–259. [PMID: 18875046]
3.  Sarda, L. and Desnuelle, P. Action de la lipase pancréatique sur les esters en émulsion. Biochim. Biophys. Acta 30 (1958) 513–521. [PMID: 13618257]
4.  Lynn, W.S. and Perryman, N.C. Properties and purification of adipose tissue lipase. J. Biol. Chem. 235 (1960) 1912–1916. [PMID: 14419169]
5.  Paznokas, J.L. and Kaplan, A. Purification and properties of a triacylglycerol lipase from Mycobacterium phlei. Biochim. Biophys. Acta 487 (1977) 405–421. [PMID: 18200]
6.  Tiruppathi, C. and Balasubramanian, K.A. Purification and properties of an acid lipase from human gastric juice. Biochim. Biophys. Acta 712 (1982) 692–697. [PMID: 7126632]
7.  Hills, M.J. and Mukherjee, K.D. Triacylglycerol lipase from rape (Brassica napus L.) suitable for biotechnological purposes. Appl. Biochem. Biotechnol. 26 (1990) 1–10. [PMID: 2268143]
8.  Winkler, F.K., D'Arcy, A. and Hunziker, W. Structure of human pancreatic lipase. Nature 343 (1990) 771–774. [PMID: 2106079]
9.  Kim, K.K., Song, H.K., Shin, D.H., Hwang, K.Y. and Suh, S.W. The crystal structure of a triacylglycerol lipase from Pseudomonas cepacia reveals a highly open conformation in the absence of a bound inhibitor. Structure 5 (1997) 173–185. [PMID: 9032073]
10.  Kurat, C.F., Natter, K., Petschnigg, J., Wolinski, H., Scheuringer, K., Scholz, H., Zimmermann, R., Leber, R., Zechner, R. and Kohlwein, S.D. Obese yeast: triglyceride lipolysis is functionally conserved from mammals to yeast. J. Biol. Chem. 281 (2006) 491–500. [PMID: 16267052]
11.  Ranaldi, S., Belle, V., Woudstra, M., Bourgeas, R., Guigliarelli, B., Roche, P., Vezin, H., Carriere, F. and Fournel, A. Amplitude of pancreatic lipase lid opening in solution and identification of spin label conformational subensembles by combining continuous wave and pulsed EPR spectroscopy and molecular dynamics. Biochemistry 49 (2010) 2140–2149. [PMID: 20136147]
[EC 3.1.1.3 created 1961]
 
 
EC 3.1.1.40     
Accepted name: orsellinate-depside hydrolase
Reaction: orsellinate depside + H2O = 2 orsellinate
Glossary: orsellinate = 2,4-dihydroxy-6-methylbenzoate
Other name(s): lecanorate hydrolase
Systematic name: orsellinate-depside hydrolase
Comments: The enzyme will only hydrolyse those substrates based on the 2,4-dihydroxy-6-methylbenzoate structure that also have a free hydroxy group ortho to the depside linkage.
References:
1.  Schultz, J. and Mosbach, K. Studies on lichen enzymes. Purification and properties of an orsellinate depside hydrolase obtained from Lasallia pustulata. Eur. J. Biochem. 22 (1971) 153–157. [PMID: 5116606]
[EC 3.1.1.40 created 1976]
 
 
EC 3.1.1.83     
Accepted name: monoterpene ε-lactone hydrolase
Reaction: (1) isoprop(en)ylmethyloxepan-2-one + H2O = 6-hydroxyisoprop(en)ylmethylhexanoate (general reaction)
(2) 4-isopropenyl-7-methyloxepan-2-one + H2O = 6-hydroxy-3-isopropenylheptanoate
(3) 7-isopropyl-4-methyloxepan-2-one + H2O = 6-hydroxy-3,7-dimethyloctanoate
Other name(s): MLH
Systematic name: isoprop(en)ylmethyloxepan-2-one lactonohydrolase
Comments: The enzyme catalyses the ring opening of ε-lactones which are formed during degradation of dihydrocarveol by the Gram-positive bacterium Rhodococcus erythropolis DCL14. The enzyme also acts on ethyl caproate, indicating that it is an esterase with a preference for lactones (internal cyclic esters). The enzyme is not stereoselective.
References:
1.  van der Vlugt-Bergmans , C.J. and van der Werf , M.J. Genetic and biochemical characterization of a novel monoterpene ε-lactone hydrolase from Rhodococcus erythropolis DCL14. Appl. Environ. Microbiol. 67 (2001) 733–741. [PMID: 11157238]
[EC 3.1.1.83 created 2008]
 
 
EC 3.1.1.96     
Accepted name: D-aminoacyl-tRNA deacylase
Reaction: (1) a D-aminoacyl-tRNA + H2O = a D-amino acid + tRNA
(2) glycyl-tRNAAla + H2O = glycine + tRNAAla
Other name(s): Dtd2; D-Tyr-tRNA(Tyr) deacylase; D-Tyr-tRNATyr deacylase; D-tyrosyl-tRNATyr aminoacylhydrolase; dtdA (gene name)
Systematic name: D-aminoacyl-tRNA aminoacylhydrolase
Comments: The enzyme, found in all domains of life, can cleave mischarged glycyl-tRNAAla [5]. The enzyme from Escherichia coli can cleave D-tyrosyl-tRNATyr, D-aspartyl-tRNAAsp and D-tryptophanyl-tRNATrp [1]. Whereas the enzyme from the archaeon Pyrococcus abyssi is a zinc protein, the enzyme from Escherichia coli does not carry any zinc [2].
References:
1.  Soutourina, J., Plateau, P. and Blanquet, S. Metabolism of D-aminoacyl-tRNAs in Escherichia coli and Saccharomyces cerevisiae cells. J. Biol. Chem. 275 (2000) 32535–32542. [PMID: 10918062]
2.  Ferri-Fioni, M.L., Schmitt, E., Soutourina, J., Plateau, P., Mechulam, Y. and Blanquet, S. Structure of crystalline D-Tyr-tRNA(Tyr) deacylase. A representative of a new class of tRNA-dependent hydrolases. J. Biol. Chem. 276 (2001) 47285–47290. [PMID: 11568181]
3.  Ferri-Fioni, M.L., Fromant, M., Bouin, A.P., Aubard, C., Lazennec, C., Plateau, P. and Blanquet, S. Identification in archaea of a novel D-Tyr-tRNATyr deacylase. J. Biol. Chem. 281 (2006) 27575–27585. [PMID: 16844682]
4.  Wydau, S., Ferri-Fioni, M.L., Blanquet, S. and Plateau, P. GEK1, a gene product of Arabidopsis thaliana involved in ethanol tolerance, is a D-aminoacyl-tRNA deacylase. Nucleic Acids Res. 35 (2007) 930–938. [PMID: 17251192]
5.  Pawar, K.I., Suma, K., Seenivasan, A., Kuncha, S.K., Routh, S.B., Kruparani, S.P. and Sankaranarayanan, R. Role of D-aminoacyl-tRNA deacylase beyond chiral proofreading as a cellular defense against glycine mischarging by AlaRS. Elife 6:e24001 (2017). [PMID: 28362257]
[EC 3.1.1.96 created 2014, modified 2019]
 
 
EC 3.1.3.93     
Accepted name: L-galactose 1-phosphate phosphatase
Reaction: β-L-galactose 1-phosphate + H2O = L-galactose + phosphate
Other name(s): VTC4 (gene name) (ambiguous); IMPL2 (gene name) (ambiguous)
Systematic name: β-L-galactose-1-phosphate phosphohydrolase
Comments: The enzyme from plants also has the activity of EC 3.1.3.25, inositol-phosphate phosphatase. The enzymes have very low activity with D-galactose 1-phosphate (cf. EC 3.1.3.94, D-galactose 1-phosphate phosphatase).
References:
1.  Laing, W.A., Bulley, S., Wright, M., Cooney, J., Jensen, D., Barraclough, D. and MacRae, E. A highly specific L-galactose-1-phosphate phosphatase on the path to ascorbate biosynthesis. Proc. Natl. Acad. Sci. USA 101 (2004) 16976–16981. [PMID: 15550539]
2.  Torabinejad, J., Donahue, J.L., Gunesekera, B.N., Allen-Daniels, M.J. and Gillaspy, G.E. VTC4 is a bifunctional enzyme that affects myoinositol and ascorbate biosynthesis in plants. Plant Physiol. 150 (2009) 951–961. [PMID: 19339506]
3.  Petersen, L.N., Marineo, S., Mandala, S., Davids, F., Sewell, B.T. and Ingle, R.A. The missing link in plant histidine biosynthesis: Arabidopsis myoinositol monophosphatase-like2 encodes a functional histidinol-phosphate phosphatase. Plant Physiol. 152 (2010) 1186–1196. [PMID: 20023146]
[EC 3.1.3.93 created 2014]
 
 
EC 3.1.3.95     
Accepted name: phosphatidylinositol-3,5-bisphosphate 3-phosphatase
Reaction: 1-phosphatidyl-1D-myo-inositol 3,5-bisphosphate + H2O = 1-phosphatidyl-1D-myo-inositol 5-phosphate + phosphate
Glossary: 1-phosphatidyl-1D-myo-inositol 5-phosphate = PtdIns5P
1-phosphatidyl-1D-myo-inositol 3,5-bisphosphate = PtdIns(3,5)P2
Other name(s): MTMR; PtdIns-3,5-P2 3-Ptase
Systematic name: 1-phosphatidyl-1D-myo-inositol-3,5-bisphosphate 3-phosphohydrolase
Comments: The enzyme is found in both plants and animals. It also has the activity of EC 3.1.3.64 (phosphatidylinositol-3-phosphatase).
References:
1.  Walker, D.M., Urbe, S., Dove, S.K., Tenza, D., Raposo, G. and Clague, M.J. Characterization of MTMR3. an inositol lipid 3-phosphatase with novel substrate specificity. Curr. Biol. 11 (2001) 1600–1605. [PMID: 11676921]
2.  Berger, P., Bonneick, S., Willi, S., Wymann, M. and Suter, U. Loss of phosphatase activity in myotubularin-related protein 2 is associated with Charcot-Marie-Tooth disease type 4B1. Hum. Mol. Genet. 11 (2002) 1569–1579. [PMID: 12045210]
3.  Ding, Y., Lapko, H., Ndamukong, I., Xia, Y., Al-Abdallat, A., Lalithambika, S., Sadder, M., Saleh, A., Fromm, M., Riethoven, J.J., Lu, G. and Avramova, Z. The Arabidopsis chromatin modifier ATX1, the myotubularin-like AtMTM and the response to drought. Plant Signal. Behav. 4 (2009) 1049–1058. [PMID: 19901554]
[EC 3.1.3.95 created 2014]
 
 
EC 3.1.3.96     
Accepted name: pseudouridine 5′-phosphatase
Reaction: pseudouridine 5′-phosphate + H2O = pseudouridine + phosphate
Other name(s): pseudouridine 5′-monophosphatase; 5′-PsiMPase; HDHD1
Systematic name: pseudouridine 5′-phosphohydrolase
Comments: Requires Mg2+ for activity.
References:
1.  Preumont, A., Rzem, R., Vertommen, D. and Van Schaftingen, E. HDHD1, which is often deleted in X-linked ichthyosis, encodes a pseudouridine-5′-phosphatase. Biochem. J. 431 (2010) 237–244. [PMID: 20722631]
[EC 3.1.3.96 created 2014]
 
 
EC 3.1.3.100     
Accepted name: thiamine phosphate phosphatase
Reaction: thiamine phosphate + H2O = thiamine + phosphate
Systematic name: thiamine phosphate phosphohydrolase
Comments: The enzyme participates in the thiamine biosynthesis pathway in eukaryotes and a few prokaryotes. These organisms lack EC 2.7.4.16, thiamine-phosphate kinase, and need to convert thiamine phosphate to thiamine diphosphate, the active form of the vitamin, by first removing the phosphate group, followed by diphosphorylation by EC 2.7.6.2, thiamine diphosphokinase.
References:
1.  Sanemori, H., Egi, Y. and Kawasaki, T. Pathway of thiamine pyrophosphate synthesis in Micrococcus denitrificans. J. Bacteriol. 126 (1976) 1030–1036. [PMID: 181359]
2.  Komeda, Y., Tanaka, M. and Nishimune, T. A th-1 mutant of Arabidopsis thaliana is defective for a thiamin-phosphate-synthesizing enzyme: thiamin phosphate pyrophosphorylase. Plant Physiol. 88 (1988) 248–250. [PMID: 16666289]
3.  Schweingruber, A.M., Dlugonski, J., Edenharter, E. and Schweingruber, M.E. Thiamine in Schizosaccharomyces pombe: dephosphorylation, intracellular pool, biosynthesis and transport. Curr. Genet. 19 (1991) 249–254. [PMID: 1868574]
4.  Muller, I.B., Bergmann, B., Groves, M.R., Couto, I., Amaral, L., Begley, T.P., Walter, R.D. and Wrenger, C. The vitamin B1 metabolism of Staphylococcus aureus is controlled at enzymatic and transcriptional levels. PLoS One 4:e7656 (2009). [PMID: 19888457]
5.  Kolos, I.K. and Makarchikov, A.F. [Identification of thiamine monophosphate hydrolyzing enzymes in chicken liver] Ukr. Biochem. J. 86 (2014) 39–49. [PMID: 25816604] (in Russian)
6.  Mimura, M., Zallot, R., Niehaus, T.D., Hasnain, G., Gidda, S.K., Nguyen, T.N., Anderson, E.M., Mullen, R.T., Brown, G., Yakunin, A.F., de Crecy-Lagard, V., Gregory, J.F., 3rd, McCarty, D.R. and Hanson, A.D. Arabidopsis TH2 encodes the orphan enzyme thiamin monophosphate phosphatase. Plant Cell 28 (2016) 2683–2696. [PMID: 27677881]
[EC 3.1.3.100 created 2016]
 
 
EC 3.1.3.106     
Accepted name: 2-lysophosphatidate phosphatase
Reaction: a 1-acyl-sn-glycerol 3-phosphate + H2O = a 1-acyl-sn-glycerol + phosphate
Other name(s): 1-acyl-sn-glycerol 3-phosphatase; CPC3 (gene name); PHM8 (gene name)
Systematic name: 1-acyl-sn-glycerol 3-phosphate phosphohydrolase
Comments: The enzyme has been studied from the plants Arachis hypogaea (peanut) and Arabidopsis thaliana (thale cress) and from the yeast Saccharomyces cerevisiae. The enzyme from yeast, but not from the plants, requires Mg2+.
References:
1.  Shekar, S., Tumaney, A.W., Rao, T.J. and Rajasekharan, R. Isolation of lysophosphatidic acid phosphatase from developing peanut cotyledons. Plant Physiol. 128 (2002) 988–996. [PMID: 11891254]
2.  Reddy, V.S., Singh, A.K. and Rajasekharan, R. The Saccharomyces cerevisiae PHM8 gene encodes a soluble magnesium-dependent lysophosphatidic acid phosphatase. J. Biol. Chem. 283 (2008) 8846–8854. [PMID: 18234677]
3.  Reddy, V.S., Rao, D.K. and Rajasekharan, R. Functional characterization of lysophosphatidic acid phosphatase from Arabidopsis thaliana. Biochim. Biophys. Acta 1801 (2010) 455–461. [PMID: 20045079]
[EC 3.1.3.106 created 2019]
 
 
EC 3.1.4.11     
Accepted name: phosphoinositide phospholipase C
Reaction: 1-phosphatidyl-1D-myo-inositol 4,5-bisphosphate + H2O = 1D-myo-inositol 1,4,5-trisphosphate + diacylglycerol
Other name(s): triphosphoinositide phosphodiesterase; phosphoinositidase C; 1-phosphatidylinositol-4,5-bisphosphate phosphodiesterase; monophosphatidylinositol phosphodiesterase; phosphatidylinositol phospholipase C; PI-PLC; 1-phosphatidyl-D-myo-inositol-4,5-bisphosphate inositoltrisphosphohydrolase
Systematic name: 1-phosphatidyl-1D-myo-inositol-4,5-bisphosphate inositoltrisphosphohydrolase
Comments: These enzymes form some of the cyclic phosphate Ins(cyclic1,2)P(4,5)P2 as well as Ins(1,4,5)P3. They show activity towards phosphatidylinositol, i.e., the activity of EC 4.6.1.13, phosphatidylinositol diacylglycerol-lyase, in vitro at high [Ca2+]. Four β-isoforms regulated by G-proteins, two γ-forms regulated by tyrosine kinases, four δ-forms regulated at least in part by calcium and an ε-form, probably regulated by the oncogene ras, have been found.
References:
1.  Downes, C.P. and Michell, R.H. The polyphosphoinositide phosphodiesterase of erythrocyte membranes. Biochem. J. 198 (1981) 133–140. [PMID: 6275838]
2.  Thompson, W. and Dawson, R.M.C. The triphosphoinositide phosphodiesterase of brain tissue. Biochem. J. 91 (1964) 237–243. [PMID: 4284484]
3.  Rhee, S.G. and Bae, Y.S. Regulation of phosphoinositide-specific phospholipase C isozymes. J. Biol. Chem. 272 (1997) 15045–15048. [PMID: 9182519]
[EC 3.1.4.11 created 1972, modified 2002]
 
 
EC 3.1.26.11     
Accepted name: tRNase Z
Reaction: endonucleolytic cleavage of RNA, removing extra 3′ nucleotides from tRNA precursor, generating 3′ termini of tRNAs. A 3′-hydroxy group is left at the tRNA terminus and a 5′-phosphoryl group is left at the trailer molecule
Other name(s): 3 tRNase; tRNA 3 endonuclease; RNase Z; 3′ tRNase
Comments: No cofactor requirements. An homologous enzyme to that found in Arabidopsis thaliana has been found in Methanococcus janaschii.
References:
1.  Schiffer, S., Rösch, S. and Marchfelder, A. Assigning a function to a conserved group of proteins: the tRNA 3′-processing enzymes. EMBO J. 21 (2002) 2769–2777. [PMID: 12032089]
2.  Mayer, M., Schiffer, S. and Marchfelder, A. tRNA 3′ processing in plants: nuclear and mitochondrial activities differ. Biochemistry 39 (2000) 2096–2105. [PMID: 10684660]
3.  Schiffer, S., Helm, M., Theobald-Dietrich, A., Giege, R. and Marchfelder, A. The plant tRNA 3′ processing enzyme has a broad substrate spectrum. Biochemistry 40 (2001) 8264–8272. [PMID: 11444972]
4.  Kunzmann, A., Brennicke, A. and Marchfelder, A. 5′ end maturation and RNA editing have to precede tRNA 3′ processing in plant mitochondria. Proc. Natl. Acad. Sci. USA 95 (1998) 108–113. [PMID: 9419337]
5.  Mörl, M. and Marchfelder, A. The final cut. The importance of tRNA 3′-processing. EMBO Rep. 2 (2001) 17–20. [PMID: 11252717]
6.  Minagawa, A., Takaku, H., Takagi, M. and Nashimoto, M. A novel endonucleolytic mechanism to generate the CCA 3′ termini of tRNA molecules in Thermotoga maritima. J. Biol. Chem. 279 (2004) 15688–15697. [PMID: 14749326]
7.  Takaku, H., Minagawa, A., Takagi, M. and Nashimoto, M. A candidate prostate cancer susceptibility gene encodes tRNA 3′ processing endoribonuclease. Nucleic Acids Res. 31 (2003) 2272–2278. [PMID: 12711671]
[EC 3.1.26.11 created 2002]
 
 
EC 3.2.1.107     
Accepted name: protein-glucosylgalactosylhydroxylysine glucosidase
Reaction: [collagen]-(5R)-5-O-[α-D-glucosyl-(1→2)-β-D-galactosyl]-5-hydroxy-L-lysine + H2O = D-glucose + [collagen]-(5R)-5-O-(β-D-galactosyl)-5-hydroxy-L-lysine
Other name(s): PGGHG (gene name); 2-O-α-D-glucopyranosyl-5-O-α-D-galactopyranosylhydroxy-L-lysine glucohydrolase; protein-α-D-glucosyl-1,2-β-D-galactosyl-L-hydroxylysine glucohydrolase; protein-α-D-glucosyl-(1→2)-β-D-galactosyl-L-hydroxylysine glucohydrolase
Systematic name: [collagen]-(5R)-5-O-[α-D-glucosyl-(1→2)-β-D-galactosyl]-5-hydroxy-L-lysine glucohydrolase
Comments: The enzyme specifically hydrolyses glucose from α-D-glucosyl-(1→2)-β-D-galactosyl disaccharide units that are linked to hydroxylysine residues of collagen and collagen-like proteins. Acetylation of the ε-amino group of the glycosylated hydroxylysine abolishes activity.
References:
1.  Hamazaki, H. and Hotta, K. Purification and characterization of an α-glucosidase specific for hydroxylysine-linked disaccharide of collagen. J. Biol. Chem. 254 (1979) 9682–9687. [PMID: 385589]
2.  Hamazaki, H. and Hotta, K. Enzymatic hydrolysis of disaccharide unit of collagen. Isolation of 2-O-α-D-glucopyranosyl-O-β-D-galactopyranosyl-hydroxylysine glucohydrolase from rat spleens. Eur. J. Biochem. 111 (1980) 587–591. [PMID: 7460918]
3.  Sternberg, M. and Shapiro, R.G. Studies on the catabolism of the hydroxylysine-linked disaccharide units of basement membranes and collagens. Isolation and characterization of a rat kidney α-glucosidase of high specificity. J. Biol. Chem. 254 (1979) 10329–10336. [PMID: 385599]
4.  Hamazaki, H. and Hamazaki, M.H. Catalytic site of human protein-glucosylgalactosylhydroxylysine glucosidase: Three crucial carboxyl residues were determined by cloning and site-directed mutagenesis. Biochem. Biophys. Res. Commun. 469 (2016) 357–362. [PMID: 26682924]
[EC 3.2.1.107 created 1984]
 
 
EC 3.2.1.165     
Accepted name: exo-1,4-β-D-glucosaminidase
Reaction: Hydrolysis of chitosan or chitosan oligosaccharides to remove successive D-glucosamine residues from the non-reducing termini
Glossary: GlcN = D-glucosamine = 2-amino-2-deoxy-D-glucopyranose
GlcNAc = N-acetyl-D-glucosamine
Other name(s): CsxA; GlcNase; exochitosanase; GlmA; exo-β-D-glucosaminidase; chitosan exo-1,4-β-D-glucosaminidase
Systematic name: chitosan exo-(1→4)-β-D-glucosaminidase
Comments: Chitosan is a partially or totally N-deacetylated chitin derivative that is found in the cell walls of some phytopathogenic fungi and comprises D-glucosamine residues with a variable content of GlcNAc residues [4]. Acts specifically on chitooligosaccharides and chitosan, having maximal activity on chitotetraose, chitopentaose and their corresponding alcohols [1]. The enzyme can degrade GlcN-GlcNAc but not GlcNAc-GlcNAc [3]. A member of the glycoside hydrolase family 2 (GH-2) [4].
References:
1.  Nanjo, F., Katsumi, R. and Sakai, K. Purification and characterization of an exo-β-D-glucosaminidase, a novel type of enzyme, from Nocardia orientalis. J. Biol. Chem. 265 (1990) 10088–10094. [PMID: 2351651]
2.  Nogawa, M., Takahashi, H., Kashiwagi, A., Ohshima, K., Okada, H. and Morikawa, Y. Purification and characterization of exo-β-D-glucosaminidase from a cellulolytic fungus, Trichoderma reesei PC-3-7. Appl. Environ. Microbiol. 64 (1998) 890–895. [PMID: 16349528]
3.  Fukamizo, T., Fleury, A., Côté, N., Mitsutomi, M. and Brzezinski, R. Exo-β-D-glucosaminidase from Amycolatopsis orientalis: catalytic residues, sugar recognition specificity, kinetics, and synergism. Glycobiology 16 (2006) 1064–1072. [PMID: 16877749]
4.  Côté, N., Fleury, A., Dumont-Blanchette, E., Fukamizo, T., Mitsutomi, M. and Brzezinski, R. Two exo-β-D-glucosaminidases/exochitosanases from actinomycetes define a new subfamily within family 2 of glycoside hydrolases. Biochem. J. 394 (2006) 675–686. [PMID: 16316314]
5.  Ike, M., Isami, K., Tanabe, Y., Nogawa, M., Ogasawara, W., Okada, H. and Morikawa, Y. Cloning and heterologous expression of the exo-β-D-glucosaminidase-encoding gene (gls93) from a filamentous fungus, Trichoderma reesei PC-3-7. Appl. Microbiol. Biotechnol. 72 (2006) 687–695. [PMID: 16636831]
[EC 3.2.1.165 created 2008]
 
 
EC 3.2.1.175     
Accepted name: β-D-glucopyranosyl abscisate β-glucosidase
Reaction: D-glucopyranosyl abscisate + H2O = D-glucose + abscisate
Other name(s): AtBG1; ABA-β-D-glucosidase; ABA-specific β-glucosidase; ABA-GE hydrolase; β-D-glucopyranosyl abscisate hydrolase
Systematic name: β-D-glucopyranosyl abscisate glucohydrolase
Comments: The enzyme hydrolzes the biologically inactive β-D-glucopyranosyl ester of abscisic acid to produce active abscisate. Abscisate is a phytohormone critical for plant growth, development and adaption to various stress conditions. The enzyme does not hydrolyse β-D-glucopyranosyl zeatin [1].
References:
1.  Lee, K.H., Piao, H.L., Kim, H.Y., Choi, S.M., Jiang, F., Hartung, W., Hwang, I., Kwak, J.M., Lee, I.J. and Hwang, I. Activation of glucosidase via stress-induced polymerization rapidly increases active pools of abscisic acid. Cell 126 (2006) 1109–1120. [PMID: 16990135]
2.  Kato-Noguchi, H. and Tanaka, Y. Effect of ABA-β-D-glucopyranosyl ester and activity of ABA-β-D-glucosidase in Arabidopsis thaliana. J. Plant Physiol. 165 (2008) 788–790. [PMID: 17923167]
3.  Dietz, K.J., Sauter, A., Wichert, K., Messdaghi, D. and Hartung, W. Extracellular β-glucosidase activity in barley involved in the hydrolysis of ABA glucose conjugate in leaves. J. Exp. Bot. 51 (2000) 937–944. [PMID: 10948220]
[EC 3.2.1.175 created 2011]
 
 
EC 3.2.1.177     
Accepted name: α-D-xyloside xylohydrolase
Reaction: Hydrolysis of terminal, non-reducing α-D-xylose residues with release of α-D-xylose.
Other name(s): α-xylosidase
Systematic name: α-D-xyloside xylohydrolase
Comments: The enzyme catalyses hydrolysis of a terminal, unsubstituted xyloside at the extreme reducing end of a xylogluco-oligosaccharide. Representative α-xylosidases from glycoside hydrolase family 31 utilize a two-step (double-displacement) mechanism involving a covalent glycosyl-enzyme intermediate, and retain the anomeric configuration of the product.
References:
1.  Moracci, M., Cobucci Ponzano, B., Trincone, A., Fusco, S., De Rosa, M., van Der Oost, J., Sensen, C.W., Charlebois, R.L. and Rossi, M. Identification and molecular characterization of the first α -xylosidase from an archaeon. J. Biol. Chem. 275 (2000) 22082–22089. [PMID: 10801892]
2.  Sampedro, J., Sieiro, C., Revilla, G., Gonzalez-Villa, T. and Zarra, I. Cloning and expression pattern of a gene encoding an α-xylosidase active against xyloglucan oligosaccharides from Arabidopsis. Plant Physiol. 126 (2001) 910–920. [PMID: 11402218]
3.  Crombie, H.J., Chengappa, S., Jarman, C., Sidebottom, C. and Reid, J.S. Molecular characterisation of a xyloglucan oligosaccharide-acting α-D-xylosidase from nasturtium (Tropaeolum majus L.) cotyledons that resembles plant ’apoplastic’ α-D-glucosidases. Planta 214 (2002) 406–413. [PMID: 11859845]
4.  Lovering, A.L., Lee, S.S., Kim, Y.W., Withers, S.G. and Strynadka, N.C. Mechanistic and structural analysis of a family 31 α-glycosidase and its glycosyl-enzyme intermediate. J. Biol. Chem. 280 (2005) 2105–2115. [PMID: 15501829]
5.  Iglesias, N., Abelenda, J.A., Rodino, M., Sampedro, J., Revilla, G. and Zarra, I. Apoplastic glycosidases active against xyloglucan oligosaccharides of Arabidopsis thaliana. Plant Cell Physiol. 47 (2006) 55–63. [PMID: 16267099]
6.  Okuyama, M., Kaneko, A., Mori, H., Chiba, S. and Kimura, A. Structural elements to convert Escherichia coli α-xylosidase (YicI) into α-glucosidase. FEBS Lett. 580 (2006) 2707–2711. [PMID: 16631751]
7.  Larsbrink, J., Izumi, A., Ibatullin, F., Nakhai, A., Gilbert, H.J., Davies, G.J. and Brumer, H. Structural and enzymatic characterisation of a glycoside hydrolase family 31 α-xylosidase from Cellvibrio japonicus involved in xyloglucan saccharification. Biochem. J. 436 (2011) 567–580. [PMID: 21426303]
[EC 3.2.1.177 created 2011]
 
 
EC 3.2.1.200     
Accepted name: exo-chitinase (non-reducing end)
Reaction: Hydrolysis of N,N′-diacetylchitobiose from the non-reducing end of chitin and chitodextrins.
Other name(s): chiB (gene name)
Systematic name: (1→4)-2-acetamido-2-deoxy-β-D-glucan diacetylchitobiohydrolase (non-reducing end)
Comments: The enzyme hydrolyses the second glycosidic (1→4) linkage from non-reducing ends of chitin and chitodextrin molecules, liberating N,N′-diacetylchitobiose disaccharides. cf. EC 3.2.1.201, exo-chitinase (reducing end).
References:
1.  Tanaka, T., Fukui, T. and Imanaka, T. Different cleavage specificities of the dual catalytic domains in chitinase from the hyperthermophilic archaeon Thermococcus kodakaraensis KOD1. J. Biol. Chem. 276 (2001) 35629–35635. [PMID: 11468293]
2.  Hult, E.L., Katouno, F., Uchiyam