ExplorEnz: EC 1*

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. [DOI] [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. [DOI] [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. [DOI] [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. [DOI] [PMID: 17148453]

[EC 1.3.1.75 created 2003, modified 2016]

1.3.1.76

Accepted name:

precorrin-2 dehydrogenase

Reaction:

precorrin-2 + NAD⁺ = sirohydrochlorin + NADH + H⁺

For diagram of corrin and siroheme biosynthesis (part 2), click here

Other name(s):

Met8p; SirC; CysG

Systematic name:

precorrin-2:NAD⁺ oxidoreductase

Comments:

This enzyme catalyses the second of three steps leading to the formation of siroheme from uroporphyrinogen III. The first step involves the donation of two S-adenosyl-L-methionine-derived methyl groups to carbons 2 and 7 of uroporphyrinogen III to form precorrin-2 (EC 2.1.1.107, uroporphyrin-III C-methyltransferase) and the third step involves the chelation of ferrous iron to sirohydrochlorin to form siroheme (EC 4.99.1.4, sirohydrochlorin ferrochelatase). In Saccharomyces cerevisiae, the last two steps are carried out by a single bifunctional enzyme, Met8p. In some bacteria, steps 1-3 are catalysed by a single multifunctional protein called CysG, whereas in Bacillus megaterium, three separate enzymes carry out each of the steps, with SirC being responsible for the above reaction.

Links to other databases:

BRENDA, EXPASY, Gene, KEGG, MetaCyc, PDB, CAS registry number: 227184-47-6

References:

1.	Schubert, H.L., Raux, E., Brindley, A.A., Leech, H.K., Wilson, K.S., Hill, C.P. and Warren, M.J. The structure of Saccharomyces cerevisiae Met8p, a bifunctional dehydrogenase and ferrochelatase. EMBO J. 21 (2002) 2068–2075. [DOI] [PMID: 11980703]
2.	Warren, M.J., Raux, E., Schubert, H.L. and Escalante-Semerena, J.C. The biosynthesis of adenosylcobalamin (vitamin B₁₂). Nat. Prod. Rep. 19 (2002) 390–412. [PMID: 12195810]

[EC 1.3.1.76 created 2004]

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⁺

For diagram of anthocyanin biosynthesis, click here

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].

Links to other databases:

BRENDA, EXPASY, Gene, KEGG, MetaCyc, PDB, CAS registry number: 93389-48-1

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. [DOI] [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. [DOI] [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. [DOI] [PMID: 23288883]

[EC 1.3.1.77 created 2004, modified 2016]

1.3.1.78

Accepted name:

arogenate dehydrogenase (NADP⁺)

Reaction:

L-arogenate + NADP⁺ = L-tyrosine + NADPH + CO₂

For diagram of phenylalanine and tyrosine biosynthesis, click here

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].

Links to other databases:

BRENDA, EXPASY, Gene, KEGG, MetaCyc, CAS registry number: 64295-75-6

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. [DOI] [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. [DOI] [PMID: 15171683]

[EC 1.3.1.78 created 2005]

1.3.1.79

Accepted name:

arogenate dehydrogenase [NAD(P)⁺]

Reaction:

L-arogenate + NAD(P)⁺ = L-tyrosine + NAD(P)H + CO₂

For diagram of phenylalanine and tyrosine biosynthesis, click here

Glossary:

L-arogenate = 1-[(2S)-2-amino-2-carboxyethyl]-4-hydroxycyclohexa-2,5-diene-1-carboxylate

Other name(s):

arogenic dehydrogenase (ambiguous); cyclohexadienyl dehydrogenase; pretyrosine dehydrogenase (ambiguous)

Systematic name:

L-arogenate:NAD(P)⁺ 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). Enzymes that can utilize both cofactors have been reported from some Proteobacteria, including Burkholderia caryophylli, Burkholderia cepacia, Pseudomonas marginata and Delftia acidovorans.

Links to other databases:

BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number: 64295-75-6

References:

1.	Byng, G.S., Whitaker, R.J., Gherna, R.L. and Jensen, R.A. Variable enzymological patterning in tyrosine biosynthesis as a means of determining natural relatedness among the Pseudomonadaceae. J. Bacteriol. 144 (1980) 247–257. [PMID: 7419490]

[EC 1.3.1.79 created 2005]

1.3.1.80

Transferred entry:

red chlorophyll catabolite reductase. Now classified as EC 1.3.7.12, red chlorophyll catabolite reductase

[EC 1.3.1.80 created 2007, deleted 2016]

1.3.1.81

Accepted name:

(+)-pulegone reductase

Reaction:

(1) (–)-menthone + NADP⁺ = (+)-pulegone + NADPH + H⁺
(2) (+)-isomenthone + NADP⁺ = (+)-pulegone + NADPH + H⁺

For diagram of menthol biosynthesis, click here

Systematic name:

(–)-menthone:NADP⁺ oxidoreductase

Comments:

NADH cannot replace NADPH as reductant. The Δ^8,9-double bond of (+)-cis-isopulegone and the Δ^1,2-double bond of (±)-piperitone are not substrates. The enzyme from peppermint (Mentha × piperita) converts (+)-pulegone into both (–)-menthone and (+)-isomenthone at a ratio of 70:30 for native enzyme but it does not catalyse the reverse reaction. This enzyme is a member of the medium-chain dehydrogenase/reductase superfamily.

Links to other databases:

References:

Ringer, K.L., McConkey, M.E., Davis, E.M., Rushing, G.W. and Croteau, R. Monoterpene double-bond reductases of the (-)-menthol biosynthetic pathway: isolation and characterization of cDNAs encoding (-)-isopiperitenone reductase and (+)-pulegone reductase of peppermint. Arch. Biochem. Biophys. 418 (2003) 80–92. [DOI] [PMID: 13679086]

[EC 1.3.1.81 created 2008]

1.3.1.82

Accepted name:

(-)-isopiperitenone reductase

Reaction:

(+)-cis-isopulegone + NADP⁺ = (-)-isopiperitenone + NADPH + H⁺

Systematic name:

(+)-cis-isopulegone:NADP⁺ oxidoreductase

Comments:

The reaction occurs in the opposite direction to that shown above. The enzyme participates in the menthol-biosynthesis pathway of Mentha plants. (+)-Pulegone, (+)-cis-isopulegone and (-)-menthone are not substrates. The enzyme has a preference for NADPH as the reductant, with NADH being a poor substitute [2]. The enzyme is highly regioselective for the reduction of the endocyclic 1,2-double bond, and is stereoselective, producing only the 1R-configured product. It is a member of the short-chain dehydrogenase/reductase superfamily.

Links to other databases:

References:

1.	Croteau, R. and Venkatachalam, K.V. Metabolism of monoterpenes: demonstration that (+)-cis-isopulegone, not piperitenone, is the key intermediate in the conversion of (-)-isopiperitenone to (+)-pulegone in peppermint (Mentha piperita). Arch. Biochem. Biophys. 249 (1986) 306–315. [DOI] [PMID: 3755881]
2.	Ringer, K.L., McConkey, M.E., Davis, E.M., Rushing, G.W. and Croteau, R. Monoterpene double-bond reductases of the (-)-menthol biosynthetic pathway: isolation and characterization of cDNAs encoding (-)-isopiperitenone reductase and (+)-pulegone reductase of peppermint. Arch. Biochem. Biophys. 418 (2003) 80–92. [DOI] [PMID: 13679086]

[EC 1.3.1.82 created 2008]

1.3.1.83

Accepted name:

geranylgeranyl diphosphate reductase

Reaction:

phytyl diphosphate + 3 NADP⁺ = geranylgeranyl diphosphate + 3 NADPH + 3 H⁺

For diagram of acyclic diterpenoid biosynthesis, click here

Other name(s):

geranylgeranyl reductase; CHL P

Systematic name:

geranylgeranyl-diphosphate:NADP⁺ oxidoreductase

Comments:

This enzyme also acts on geranylgeranyl-chlorophyll a. The reaction occurs in three steps. Which order the three double bonds are reduced is not known.

Links to other databases:

References:

1.	Soll, J., Schultz, G., Rudiger, W. and Benz, J. Hydrogenation of geranylgeraniol : two pathways exist in spinach chloroplasts. Plant Physiol. 71 (1983) 849–854. [PMID: 16662918]
2.	Tanaka, R., Oster, U., Kruse, E., Rudiger, W. and Grimm, B. Reduced activity of geranylgeranyl reductase leads to loss of chlorophyll and tocopherol and to partially geranylgeranylated chlorophyll in transgenic tobacco plants expressing antisense RNA for geranylgeranyl reductas. Plant Physiol. 120 (1999) 695–704. [PMID: 10398704]
3.	Keller, Y., Bouvier, F., d'Harlingue, A. and Camara, B. Metabolic compartmentation of plastid prenyllipid biosynthesis—evidence for the involvement of a multifunctional geranylgeranyl reductase. Eur. J. Biochem. 251 (1998) 413–417. [PMID: 9492312]

[EC 1.3.1.83 created 2009]

1.3.1.84

Accepted name:

acrylyl-CoA reductase (NADPH)

Reaction:

propanoyl-CoA + NADP⁺ = acryloyl-CoA + NADPH + H⁺

For diagram of the 3-hydroxypropanoate cycle, click here, for diagram of the 3-hydroxypropanoate/4-hydroxybutanoate cycle and dicarboxylate/4-hydroxybutanoate cycle in archaea, click here and for diagram of 3-(dimethylsulfonio)propanoate met

Glossary:

propanoyl-CoA = propionyl-CoA
acryloyl-CoA = acrylyl-CoA = propenoyl-CoA

Systematic name:

propanoyl-CoA:NADP⁺ oxidoreductase

Comments:

Catalyses a step in the 3-hydroxypropanoate/4-hydroxybutanoate cycle, an autotrophic CO₂ fixation pathway found in some thermoacidophilic archaea [1]. The enzyme from Sulfolobus tokodaii does not act on either NADH or crotonyl-CoA [2]. Different from EC 1.3.1.8, which acts only on enoyl-CoA derivatives of carbon chain length 4 to 16. Contains Zn²⁺.

Links to other databases:

References:

1.	Berg, I.A., Kockelkorn, D., Buckel, W. and Fuchs, G. A 3-hydroxypropionate/4-hydroxybutyrate autotrophic carbon dioxide assimilation pathway in Archaea. Science 318 (2007) 1782–1786. [DOI] [PMID: 18079405]
2.	Teufel, R., Kung, J.W., Kockelkorn, D., Alber, B.E. and Fuchs, G. 3-hydroxypropionyl-coenzyme A dehydratase and acryloyl-coenzyme A reductase, enzymes of the autotrophic 3-hydroxypropionate/4-hydroxybutyrate cycle in the Sulfolobales. J. Bacteriol. 191 (2009) 4572–4581. [DOI] [PMID: 19429610]

[EC 1.3.1.84 created 2009, modified 2014]

1.3.1.85

Accepted name:

crotonyl-CoA carboxylase/reductase

Reaction:

(2S)-ethylmalonyl-CoA + NADP⁺ = (E)-but-2-enoyl-CoA + CO₂ + NADPH + H⁺

Glossary:

(E)-but-2-enoyl-CoA = crotonyl-CoA

Other name(s):

CCR; crotonyl-CoA reductase (carboxylating)

Systematic name:

(2S)-ethylmalonyl-CoA:NADP⁺ oxidoreductase (decarboxylating)

Comments:

The reaction is catalysed in the reverse direction. This enzyme, isolated from the bacterium Rhodobacter sphaeroides, catalyses (E)-but-2-enoyl-CoA-dependent oxidation of NADPH in the presence of CO₂. When CO₂ is absent, the enzyme catalyses the reduction of (E)-but-2-enoyl-CoA to butanoyl-CoA, but with only 10% of maximal activity (relative to (E)-but-2-enoyl-CoA carboxylation).

Links to other databases:

References:

1.	Erb, T.J., Berg, I.A., Brecht, V., Muller, M., Fuchs, G. and Alber, B.E. Synthesis of C₅-dicarboxylic acids from C₂-units involving crotonyl-CoA carboxylase/reductase: the ethylmalonyl-CoA pathway. Proc. Natl. Acad. Sci. USA 104 (2007) 10631–10636. [DOI] [PMID: 17548827]
2.	Erb, T.J., Brecht, V., Fuchs, G., Muller, M. and Alber, B.E. Carboxylation mechanism and stereochemistry of crotonyl-CoA carboxylase/reductase, a carboxylating enoyl-thioester reductase. Proc. Natl. Acad. Sci. USA 106 (2009) 8871–8876. [DOI] [PMID: 19458256]

[EC 1.3.1.85 created 2011]

1.3.1.86

Accepted name:

crotonyl-CoA reductase

Reaction:

butanoyl-CoA + NADP⁺ = (E)-but-2-enoyl-CoA + NADPH + H⁺

For diagram of lysine catabolism, click here

Glossary:

(E)-but-2-enoyl-CoA = crotonyl-CoA
butanoyl-CoA = butyryl-CoA

Other name(s):

butyryl-CoA dehydrogenase; butyryl dehydrogenase; unsaturated acyl-CoA reductase; ethylene reductase; enoyl-coenzyme A reductase; unsaturated acyl coenzyme A reductase; butyryl coenzyme A dehydrogenase; short-chain acyl CoA dehydrogenase; short-chain acyl-coenzyme A dehydrogenase; 3-hydroxyacyl CoA reductase; butanoyl-CoA:(acceptor) 2,3-oxidoreductase; CCR

Systematic name:

butanoyl-CoA:NADP⁺ 2,3-oxidoreductase

Comments:

Catalyses the reaction in the reverse direction. This enzyme from Streptomyces collinus is specific for (E)-but-2-enoyl-CoA, and is proposed to provide butanoyl-CoA as a starter unit for straight-chain fatty acid biosynthesis.

Links to other databases:

References:

Wallace, K.K., Bao, Z.Y., Dai, H., Digate, R., Schuler, G., Speedie, M.K. and Reynolds, K.A. Purification of crotonyl-CoA reductase from Streptomyces collinus and cloning, sequencing and expression of the corresponding gene in Escherichia coli. Eur. J. Biochem. 233 (1995) 954–962. [DOI] [PMID: 8521864]

[EC 1.3.1.86 created 2011]

1.3.1.87

Accepted name:

3-(cis-5,6-dihydroxycyclohexa-1,3-dien-1-yl)propanoate dehydrogenase

Reaction:

(1) 3-(cis-5,6-dihydroxycyclohexa-1,3-dien-1-yl)propanoate + NAD⁺ = 3-(2,3-dihydroxyphenyl)propanoate + NADH + H⁺
(2) (2E)-3-(cis-5,6-dihydroxycyclohexa-1,3-dien-1-yl)prop-2-enoate + NAD⁺ = (2E)-3-(2,3-dihydroxyphenyl)prop-2-enoate + NADH + H⁺

For diagram of 3-phenylpropanoate catabolism, click here and for diagram of cinnamate catabolism, click here

Glossary:

(2E)-3-(2,3-dihydroxyphenyl)prop-2-enoate = trans-2,3-dihydroxycinnamate

Other name(s):

hcaB (gene name); cis-dihydrodiol dehydrogenase; 2,3-dihydroxy-2,3-dihydro-phenylpropionate dehydrogenase

Systematic name:

3-(cis-5,6-dihydroxycyclohexa-1,3-dien-1-yl)propanoate:NAD⁺ oxidoreductase

Comments:

This enzyme catalyses a step in the pathway of phenylpropanoid compounds degradation.

Links to other databases:

BRENDA, EAWAG-BBD, EXPASY, Gene, KEGG, MetaCyc

References:

1.	Díaz, E., Ferrández, A. and García, J.L. Characterization of the hca cluster encoding the dioxygenolytic pathway for initial catabolism of 3-phenylpropionic acid in Escherichia coli K-12. J. Bacteriol. 180 (1998) 2915–2923. [PMID: 9603882]

[EC 1.3.1.87 created 2011]

1.3.1.88

Accepted name:

tRNA-dihydrouridine^16/17 synthase [NAD(P)⁺]

Reaction:

(1) 5,6-dihydrouracil¹⁶ in tRNA + NAD(P)⁺ = uracil¹⁶ in tRNA + NAD(P)H + H⁺
(2) 5,6-dihydrouracil¹⁷ in tRNA + NAD(P)⁺ = uracil¹⁷ in tRNA + NAD(P)H + H⁺

Other name(s):

Dus1p; tRNA-dihydrouridine synthase 1

Systematic name:

tRNA-5,6-dihydrouracil^16/17:NAD(P)⁺ oxidoreductase

Comments:

A flavoprotein. The enzyme specifically modifies uracil¹⁶ and uracil¹⁷ in tRNA.

Links to other databases:

References:

1.	Xing, F., Hiley, S.L., Hughes, T.R. and Phizicky, E.M. The specificities of four yeast dihydrouridine synthases for cytoplasmic tRNAs. J. Biol. Chem. 279 (2004) 17850–17860. [DOI] [PMID: 14970222]
2.	Xing, F., Martzen, M.R. and Phizicky, E.M. A conserved family of Saccharomyces cerevisiae synthases effects dihydrouridine modification of tRNA. RNA 8 (2002) 370–381. [PMID: 12003496]

[EC 1.3.1.88 created 2011]

1.3.1.89

Accepted name:

tRNA-dihydrouridine⁴⁷ synthase [NAD(P)⁺]

Reaction:

5,6-dihydrouracil⁴⁷ in tRNA + NAD(P)⁺ = uracil⁴⁷ in tRNA + NAD(P)H + H⁺

Other name(s):

Dus3p; tRNA-dihydrouridine synthase 3

Systematic name:

tRNA-5,6-dihydrouracil⁴⁷:NAD(P)⁺ oxidoreductase

Comments:

A flavoenzyme. The enzyme specifically modifies uracil⁴⁷ in tRNA.

Links to other databases:

References:

1.	Xing, F., Hiley, S.L., Hughes, T.R. and Phizicky, E.M. The specificities of four yeast dihydrouridine synthases for cytoplasmic tRNAs. J. Biol. Chem. 279 (2004) 17850–17860. [DOI] [PMID: 14970222]

[EC 1.3.1.89 created 2011]

1.3.1.90

Accepted name:

tRNA-dihydrouridine^20a/20b synthase [NAD(P)⁺]

Reaction:

(1) 5,6-dihydrouracil^20a in tRNA + NAD(P)⁺ = uracil^20a in tRNA + NAD(P)H + H⁺
(2) 5,6-dihydrouracil^20b in tRNA + NAD(P)⁺ = uracil^20b in tRNA + NAD(P)H + H⁺

Other name(s):

Dus4p

Systematic name:

tRNA-5,6-dihydrouracil^20a/20b:NAD(P)⁺ oxidoreductase

Comments:

A flavoenzyme. The enzyme specifically modifies uracil^20a and uracil^20b in tRNA.

Links to other databases:

References:

1.	Xing, F., Hiley, S.L., Hughes, T.R. and Phizicky, E.M. The specificities of four yeast dihydrouridine synthases for cytoplasmic tRNAs. J. Biol. Chem. 279 (2004) 17850–17860. [DOI] [PMID: 14970222]

[EC 1.3.1.90 created 2011]

1.3.1.91

Accepted name:

tRNA-dihydrouridine²⁰ synthase [NAD(P)⁺]

Reaction:

5,6-dihydrouracil²⁰ in tRNA + NAD(P)⁺ = uracil²⁰ in tRNA + NAD(P)H + H⁺

Other name(s):

Dus2p; tRNA-dihydrouridine synthase 2

Systematic name:

tRNA-5,6-dihydrouracil²⁰:NAD(P)⁺ oxidoreductase

Comments:

A flavoenzyme [3]. The enzyme specifically modifies uracil²⁰ in tRNA.

Links to other databases:

References:

1.	Xing, F., Hiley, S.L., Hughes, T.R. and Phizicky, E.M. The specificities of four yeast dihydrouridine synthases for cytoplasmic tRNAs. J. Biol. Chem. 279 (2004) 17850–17860. [DOI] [PMID: 14970222]
2.	Xing, F., Martzen, M.R. and Phizicky, E.M. A conserved family of Saccharomyces cerevisiae synthases effects dihydrouridine modification of tRNA. RNA 8 (2002) 370–381. [PMID: 12003496]
3.	Rider, L.W., Ottosen, M.B., Gattis, S.G. and Palfey, B.A. Mechanism of dihydrouridine synthase 2 from yeast and the importance of modifications for efficient tRNA reduction. J. Biol. Chem. 284 (2009) 10324–10333. [DOI] [PMID: 19139092]
4.	Kato, T., Daigo, Y., Hayama, S., Ishikawa, N., Yamabuki, T., Ito, T., Miyamoto, M., Kondo, S. and Nakamura, Y. A novel human tRNA-dihydrouridine synthase involved in pulmonary carcinogenesis. Cancer Res. 65 (2005) 5638–5646. [DOI] [PMID: 15994936]

[EC 1.3.1.91 created 2011]

1.3.1.92

Accepted name:

artemisinic aldehyde Δ¹¹⁽¹³⁾-reductase

Reaction:

(11R)-dihydroartemisinic aldehyde + NADP⁺ = artemisinic aldehyde + NADPH + H⁺

For diagram of artemisinin biosynthesis, click here

Other name(s):

Dbr2

Systematic name:

artemisinic aldehyde:NADP⁺ oxidoreductase

Comments:

Cloned from Artemisia annua. In addition to the reduction of artemisinic aldehyde it is also able to a lesser extent to reduce artemisinic alcohol and artemisinic acid. Part of the biosyntheis of artemisinin.

Links to other databases:

References:

1.	Bertea, C.M., Freije, J.R., van der Woude, H., Verstappen, F.W., Perk, L., Marquez, V., De Kraker, J.W., Posthumus, M.A., Jansen, B.J., de Groot, A., Franssen, M.C. and Bouwmeester, H.J. Identification of intermediates and enzymes involved in the early steps of artemisinin biosynthesis in Artemisia annua. Planta Med. 71 (2005) 40–47. [DOI] [PMID: 15678372]
2.	Zhang, Y., Teoh, K.H., Reed, D.W., Maes, L., Goossens, A., Olson, D.J., Ross, A.R. and Covello, P.S. The molecular cloning of artemisinic aldehyde Δ¹¹⁽¹³⁾ reductase and its role in glandular trichome-dependent biosynthesis of artemisinin in Artemisia annua. J. Biol. Chem. 283 (2008) 21501–21508. [DOI] [PMID: 18495659]

[EC 1.3.1.92 created 2012]

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.

Links to other databases:

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. [DOI] [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. [DOI] [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. [DOI] [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. [DOI] [PMID: 15829606]

[EC 1.3.1.93 created 2012]

1.3.1.94

Accepted name:

polyprenal reductase

Reaction:

a dolichal + NADP⁺ = a ditrans,polycis-polyprenal + NADPH + H⁺

Other name(s):

SRD5A3 (gene name); DFG10 (gene name); polyprenol reductase (incorrect); ditrans,polycis-dolichol:NADP⁺ 2,3-oxidoreductase (incorrect)

Systematic name:

dolichal:NADP⁺ 2,3-oxidoreductase

Comments:

The enzyme, isolated from human fetal brain tissue but present in all eukaryotes, catalyses the reduction of the terminal double bond next to the aldehyde group in ditrans,polycis-polyprenal, as part of the pathway that produces dolichol. In mammalian cells dolichols are predominantly 18-21 isoprene units in length.

Links to other databases:

References:

1.	Sagami, H., Kurisaki, A. and Ogura, K. Formation of dolichol from dehydrodolichol is catalyzed by NADPH-dependent reductase localized in microsomes of rat liver. J. Biol. Chem. 268 (1993) 10109–10113. [DOI] [PMID: 8486680]
2.	Cantagrel, V., Lefeber, D.J., Ng, B.G., Guan, Z., Silhavy, J.L., Bielas, S.L., Lehle, L., Hombauer, H., Adamowicz, M., Swiezewska, E., De Brouwer, A.P., Blumel, P., Sykut-Cegielska, J., Houliston, S., Swistun, D., Ali, B.R., Dobyns, W.B., Babovic-Vuksanovic, D., van Bokhoven, H., Wevers, R.A., Raetz, C.R., Freeze, H.H., Morava, E., Al-Gazali, L. and Gleeson, J.G. SRD5A3 is required for converting polyprenol to dolichol and is mutated in a congenital glycosylation disorder. Cell 142 (2010) 203–217. [DOI] [PMID: 20637498]
3.	Wilson, M.P., Kentache, T., Althoff, C.R., Schulz, C., de Bettignies, G., Mateu Cabrera, G., Cimbalistiene, L., Burnyte, B., Yoon, G., Costain, G., Vuillaumier-Barrot, S., Cheillan, D., Rymen, D., Rychtarova, L., Hansikova, H., Bury, M., Dewulf, J.P., Caligiore, F., Jaeken, J., Cantagrel, V., Van Schaftingen, E., Matthijs, G., Foulquier, F. and Bommer, G.T. A pseudoautosomal glycosylation disorder prompts the revision of dolichol biosynthesis. Cell (2024) . [DOI] [PMID: 38821050]

[EC 1.3.1.94 created 2012, modified 2024]

1.3.1.95

Accepted name:

acrylyl-CoA reductase (NADH)

Reaction:

propanoyl-CoA + NAD⁺ = acryloyl-CoA + NADH + H⁺

For diagram of 3-(dimethylsulfonio)propanoate metabolism, click here

Glossary:

propanoyl-CoA = propionyl-CoA

Systematic name:

propanoyl-CoA:NAD⁺ oxidoreductase

Comments:

Contains FAD. The reaction is catalysed in the opposite direction to that shown. The enzyme from the bacterium Clostridium propionicum is a complex that includes an electron-transfer flavoprotein (ETF). The ETF is reduced by NADH and transfers the electrons to the active site. Catalyses a step in a pathway for L-alanine fermentation to propanoate [1]. cf. EC 1.3.1.84, acrylyl-CoA reductase (NADPH).

Links to other databases:

References:

1.	Hetzel, M., Brock, M., Selmer, T., Pierik, A.J., Golding, B.T. and Buckel, W. Acryloyl-CoA reductase from Clostridium propionicum. An enzyme complex of propionyl-CoA dehydrogenase and electron-transferring flavoprotein. Eur. J. Biochem. 270 (2003) 902–910. [DOI] [PMID: 12603323]
2.	Kandasamy, V., Vaidyanathan, H., Djurdjevic, I., Jayamani, E., Ramachandran, K.B., Buckel, W., Jayaraman, G. and Ramalingam, S. Engineering Escherichia coli with acrylate pathway genes for propionic acid synthesis and its impact on mixed-acid fermentation. Appl. Microbiol. Biotechnol. 97 (2013) 1191–1200. [DOI] [PMID: 22810300]

[EC 1.3.1.95 created 2012]

1.3.1.96

Accepted name:

Botryococcus squalene synthase

Reaction:

squalene + diphosphate + NADP⁺ = presqualene diphosphate + NADPH + H⁺

For diagram of botryococcus braunii BOT22 squalene and botrycoccene biosynthesis, click here

Other name(s):

SSL-2 (gene name)

Systematic name:

squalene:NADP⁺ oxidoreductase

Comments:

Isolated from the green alga Botryococcus braunii BOT22. Acts in the reverse direction. cf. EC 2.5.1.21, squalene synthase, where squalene is formed directly from farnesyl diphosphate.

Links to other databases:

References:

1.	Niehaus, T.D., Okada, S., Devarenne, T.P., Watt, D.S., Sviripa, V. and Chappell, J. Identification of unique mechanisms for triterpene biosynthesis in Botryococcus braunii. Proc. Natl. Acad. Sci. USA 108 (2011) 12260–12265. [DOI] [PMID: 21746901]

[EC 1.3.1.96 created 2012]

1.3.1.97

Accepted name:

botryococcene synthase

Reaction:

C₃₀ botryococcene + NADP⁺ + diphosphate = presqualene diphosphate + NADPH + H⁺

For diagram of botryococcus braunii BOT22 squalene and botrycoccene biosynthesis, click here

Glossary:

C₃₀ botryococcene = (10S,13R)-10-ethenyl-2,6,10,13,17,21-hexamethyldocosa-2,5,11,16,20-pentaene

Other name(s):

SSL-3 (gene name)

Systematic name:

C₃₀ botryococcene:NADP⁺ oxidoreductase

Comments:

Isolated from the green alga Botryococcus braunii BOT22. Acts in the reverse direction. Involved in the production of botryococcenes, which are triterpenoid hydrocarbons of isoprenoid origin produced in large amount by this alga.

Links to other databases:

References:

1.	Niehaus, T.D., Okada, S., Devarenne, T.P., Watt, D.S., Sviripa, V. and Chappell, J. Identification of unique mechanisms for triterpene biosynthesis in Botryococcus braunii. Proc. Natl. Acad. Sci. USA 108 (2011) 12260–12265. [DOI] [PMID: 21746901]

[EC 1.3.1.97 created 2012]

1.3.1.98

Accepted name:

UDP-N-acetylmuramate dehydrogenase

Reaction:

UDP-N-acetyl-α-D-muramate + NADP⁺ = UDP-N-acetyl-3-O-(1-carboxyvinyl)-α-D-glucosamine + NADPH + H⁺

Other name(s):

MurB reductase; UDP-N-acetylenolpyruvoylglucosamine reductase; UDP-N-acetylglucosamine-enoylpyruvate reductase; UDP-GlcNAc-enoylpyruvate reductase; uridine diphosphoacetylpyruvoylglucosamine reductase; uridine diphospho-N-acetylglucosamine-enolpyruvate reductase; uridine-5′-diphospho-N-acetyl-2-amino-2-deoxy-3-O-lactylglucose:NADP-oxidoreductase

Systematic name:

UDP-N-acetyl-α-D-muramate:NADP⁺ oxidoreductase

Comments:

A flavoprotein (FAD). NADH can to a lesser extent replace NADPH.

Links to other databases:

BRENDA, EXPASY, Gene, KEGG, MetaCyc, PDB, CAS registry number: 39307-28-3

References:

1.	Taku, A. and Anwar, R.A. Biosynthesis of uridine diphospho-N-acetylmuramic acid. IV. Activation of uridine diphospho-N-acetylenolpyruvylglucosamine reductase by monovalent cations. J. Biol. Chem. 248 (1973) 4971. [PMID: 4717533]
2.	Taku, A., Gunetileke, K.G. and Anwar, R.A. Biosynthesis of uridine diphospho-N-acetylmuramic acid. 3. Purification and properties of uridine diphospho-N-acetylenolpyruvyl-glucosamine reductase. J. Biol. Chem. 245 (1970) 5012–5016. [PMID: 4394163]
3.	van Heijenoort, J. Recent advances in the formation of the bacterial peptidoglycan monomer unit. Nat. Prod. Rep. 18 (2001) 503–519. [PMID: 11699883]

[EC 1.3.1.98 created 1976 as EC 1.1.1.158, modified 1983, modified 2002, transferred 2013 to EC 1.3.1.98]

1.3.1.99

Transferred entry:

iridoid synthase. Now known to be catalyzed by two different enzymes, EC 1.3.1.122, (S)-8-oxocitronellyl enol synthase, and EC 5.5.1.34, (+)-cis,trans-nepetalactol synthase

[EC 1.3.1.99 created 2013, deleted 2019]

1.3.1.100

Accepted name:

chanoclavine-I aldehyde reductase

Reaction:

dihydrochanoclavine-I aldehyde + NADP⁺ = chanoclavine-I aldehyde + NADPH + H⁺

For diagram of fumigaclavin alkaloid biosynthesis, click here

Glossary:

chanoclavine-I aldehyde = (1E)-2-methyl-3-[(4R,5R)-4-(methylamino)-1,3,4,5-tetrahydrobenz[cd]indol-5-yl]prop-2-enal

Other name(s):

FgaOx3; easA (gene name)

Systematic name:

chanoclavine-I aldehyde:NAD⁺ oxidoreductase

Comments:

Contains FMN. The enzyme participates in the biosynthesis of fumigaclavine C, an ergot alkaloid produced by some fungi of the Trichocomaceae family. The enzyme catalyses the reduction of chanoclavine-I aldehyde to dihydrochanoclavine-I aldehyde. This hydrolyses spontaneously to form 6,8-dimethyl-6,7-didehydroergoline, which is converted to festuclavine by EC 1.5.1.44, festuclavine dehydrogenase.

Links to other databases:

References:

1.	Coyle, C.M., Cheng, J.Z., O'Connor, S.E. and Panaccione, D.G. An old yellow enzyme gene controls the branch point between Aspergillus fumigatus and Claviceps purpurea ergot alkaloid pathways. Appl. Environ. Microbiol. 76 (2010) 3898–3903. [DOI] [PMID: 20435769]
2.	Cheng, J.Z., Coyle, C.M., Panaccione, D.G. and O'Connor, S.E. A role for Old Yellow Enzyme in ergot alkaloid biosynthesis. J. Am. Chem. Soc. 132 (2010) 1776–1777. [DOI] [PMID: 20102147]
3.	Wallwey, C., Matuschek, M., Xie, X.L. and Li, S.M. Ergot alkaloid biosynthesis in Aspergillus fumigatus: Conversion of chanoclavine-I aldehyde to festuclavine by the festuclavine synthase FgaFS in the presence of the old yellow enzyme FgaOx3. Org. Biomol. Chem. 8 (2010) 3500–3508. [DOI] [PMID: 20526482]
4.	Xie, X., Wallwey, C., Matuschek, M., Steinbach, K. and Li, S.M. Formyl migration product of chanoclavine-I aldehyde in the presence of the old yellow enzyme FgaOx3 from Aspergillus fumigatus: a NMR structure elucidation. Magn. Reson. Chem. 49 (2011) 678–681. [DOI] [PMID: 21898587]

[EC 1.3.1.100 created 2013]

1.3.1.101

Accepted name:

2,3-bis-O-geranylgeranyl-sn-glycerol 1-phosphate reductase [NAD(P)H]

Reaction:

2,3-bis-(O-phytanyl)-sn-glycerol 1-phosphate + 8 NAD(P)⁺ = 2,3-bis-(O-geranylgeranyl)-sn-glycerol 1-phosphate + 8 NAD(P)H + 8 H⁺

For diagram of archaetidylserine biosynthesis, click here

Glossary:

phytanol = (7R,11R,15R)-3,7,11,15-tetramethylhexadecan-1-ol

Other name(s):

digeranylgeranylglycerophospholipid reductase; Ta0516m (gene name); DGGGPL reductase; 2,3-digeranylgeranylglycerophospholipid reductase

Systematic name:

2,3-bis-(O-phytany)l-sn-glycerol 1-phosphate:NAD(P)⁺ oxidoreductase

Comments:

A flavoprotein (FAD). The enzyme from the archaeon Thermoplasma acidophilum is involved in the biosynthesis of membrane lipids. In vivo the reaction occurs in the reverse direction with the formation of 2,3-bis-O-phytanyl-sn-glycerol 1-phosphate. cf. EC 1.3.7.11, 2,3-bis-O-geranylgeranyl-sn-glycero-phospholipid reductase.

Links to other databases:

References:

1.	Nishimura, Y. and Eguchi, T. Biosynthesis of archaeal membrane lipids: digeranylgeranylglycerophospholipid reductase of the thermoacidophilic archaeon Thermoplasma acidophilum. J. Biochem. 139 (2006) 1073–1081. [DOI] [PMID: 16788058]
2.	Nishimura, Y. and Eguchi, T. Stereochemistry of reduction in digeranylgeranylglycerophospholipid reductase involved in the biosynthesis of archaeal membrane lipids from Thermoplasma acidophilum. Bioorg. Chem. 35 (2007) 276–283. [DOI] [PMID: 17275067]
3.	Xu, Q., Eguchi, T., Mathews, I.I., Rife, C.L., Chiu, H.J., Farr, C.L., Feuerhelm, J., Jaroszewski, L., Klock, H.E., Knuth, M.W., Miller, M.D., Weekes, D., Elsliger, M.A., Deacon, A.M., Godzik, A., Lesley, S.A. and Wilson, I.A. Insights into substrate specificity of geranylgeranyl reductases revealed by the structure of digeranylgeranylglycerophospholipid reductase, an essential enzyme in the biosynthesis of archaeal membrane lipids. J. Mol. Biol. 404 (2010) 403–417. [DOI] [PMID: 20869368]

[EC 1.3.1.101 created 2013]

1.3.1.102

Accepted name:

2-alkenal reductase (NADP⁺)

Reaction:

an n-alkanal + NADP⁺ = an alk-2-enal + NADPH + H⁺

Other name(s):

NADPH-dependent alkenal/one oxidoreductase; NADPH:2-alkenal α,β-hydrogenase

Systematic name:

n-alkanal:NADP⁺ 2-oxidoreductase

Comments:

Shows highest activity with 1-nitrocyclohexene but also has significant activity with 2-methylpentenal and trans-cinnamaldehyde [3]. Involved in the detoxication of α,β-unsaturated aldehydes and ketones. Has very low activity with NAD as reductant (cf. EC 1.3.1.74, 2-alkenal reductase [NAD(P)⁺]).

Links to other databases:

References:

1.	Hirata, T., Tamura, Y., Yokobatake, N., Shimoda, K. and Ashida, Y. A 38 kDa allylic alcohol dehydrogenase from the cultured cells of Nicotiana tabacum. Phytochemistry 55 (2000) 297–303. [DOI] [PMID: 11117876]
2.	Matsushima, A., Sato, Y., Otsuka, M., Watanabe, T., Yamamoto, H. and Hirata, T. An enone reductase from Nicotiana tabacum: cDNA cloning, expression in Escherichia coli, and reduction of enones with the recombinant proteins. Bioorg. Chem. 36 (2008) 23–28. [DOI] [PMID: 17945329]
3.	Mansell, D.J., Toogood, H.S., Waller, J., Hughes, J.M.X., Levy, C.W., Gardiner, J.M., and Scrutton, N.S. Biocatalytic asymmetric alkene reduction: crystal structure and characterization of a double bond reductase from Nicotiana tabacum. ACS Catal. 3 (2013) 370–379. [PMID: 27547488]

[EC 1.3.1.102 created 2013]

1.3.1.103

Accepted name:

2-haloacrylate reductase

Reaction:

(S)-2-chloropropanoate + NADP⁺ = 2-chloroacrylate + NADPH + H⁺

Other name(s):

CAA43 (gene name)

Systematic name:

(S)-2-chloropropanoate:NADP⁺ oxidoreductase

Comments:

The enzyme acts in the degradation pathway of unsaturated organohalogen compounds by the bacterium Burkholderia sp. WS.

Links to other databases:

References:

Kurata, A., Kurihara, T., Kamachi, H. and Esaki, N. 2-Haloacrylate reductase, a novel enzyme of the medium chain dehydrogenase/reductase superfamily that catalyzes the reduction of a carbon-carbon double bond of unsaturated organohalogen compounds. J. Biol. Chem. 280 (2005) 20286–20291. [DOI] [PMID: 15781461]

[EC 1.3.1.103 created 2013]

1.3.1.104

Accepted name:

enoyl-[acyl-carrier-protein] reductase (NADPH)

Reaction:

an acyl-[acyl-carrier protein] + NADP⁺ = a trans-2,3-dehydroacyl-[acyl-carrier protein] + NADPH + H⁺

Other name(s):

acyl-ACP dehydrogenase (ambiguous); enoyl-[acyl carrier protein] (reduced nicotinamide adenine dinucleotide phosphate) reductase; NADPH 2-enoyl Co A reductase; enoyl-ACP reductase (ambiguous); fabL (gene name)

Systematic name:

acyl-[acyl-carrier protein]:NADP⁺ oxidoreductase

Comments:

The enzyme completes each cycle of fatty acid elongation by catalysing the stereospecific reduction of the double bond at position 2 of a growing fatty acid chain, while linked to the acyl-carrier protein, in an NADPH-dependent manner. This entry stands for enzymes whose stereo-specificity with respect to NADP⁺ is not known. [cf. EC 1.3.1.39 enoyl-[acyl-carrier-protein] reductase (NADPH, Re-specific), EC 1.3.1.10, enoyl-[acyl-carrier-protein] reductase (NADPH, Si-specific) and EC 1.3.1.9, enoyl-[acyl-carrier-protein] reductase (NADH)].

Links to other databases:

References:

1.	Heath, R.J., Su, N., Murphy, C.K. and Rock, C.O. The enoyl-[acyl-carrier-protein] reductases FabI and FabL from Bacillus subtilis. J. Biol. Chem. 275 (2000) 40128–40133. [DOI] [PMID: 11007778]
2.	Kim, K.H., Park, J.K., Ha, B.H., Moon, J.H. and Kim, E.E. Crystallization and preliminary X-ray crystallographic analysis of enoyl-ACP reductase III (FabL) from Bacillus subtilis. Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. 63 (2007) 246–248. [DOI] [PMID: 17329825]
3.	Kim, K.H., Ha, B.H., Kim, S.J., Hong, S.K., Hwang, K.Y. and Kim, E.E. Crystal structures of Enoyl-ACP reductases I (FabI) and III (FabL) from B. subtilis. J. Mol. Biol. 406 (2011) 403–415. [DOI] [PMID: 21185310]

[EC 1.3.1.104 created 2013]

1.3.1.105

Accepted name:

2-methylene-furan-3-one reductase

Reaction:

4-hydroxy-2,5-dimethylfuran-3(2H)-one + NADP⁺ = 4-hydroxy-5-methyl-2-methylenefuran-3(2H)-one + NADPH + H⁺

Glossary:

furaneol = 4-hydroxy-2,5-dimethylfuran-3(2H)-one
homofuraneol = 2-ethyl-4-hydroxy-5-methylfuran-3(2H)-one

Other name(s):

FaEO; SIEO; enone oxidoreductase; 4-hydroxy-2,5-dimethylfuran-3(2H)-one:NAD(P)⁺ oxidoreductase

Systematic name:

4-hydroxy-2,5-dimethylfuran-3(2H)-one:NADP⁺ oxidoreductase

Comments:

The enzyme was dicovered in strawberry (Fragaria x ananassa), where it produces furaneol, one of the major aroma compounds in the fruits. It has also been detected in tomato (Solanum lycopersicum) and pineapple (Ananas comosus). The enzyme can also act on derivatives substituted at the methylene functional group. The enzyme from the yeast Saccharomyces cerevisiae acts on (2E)-2-ethylidene-4-hydroxy-5-methylfuran-3(2H)-one and produces homofuraneol, an important aroma compound in soy sauce and miso. NADPH is the preferred cofactor.

Links to other databases:

References:

1.	Raab, T., Lopez-Raez, J.A., Klein, D., Caballero, J.L., Moyano, E., Schwab, W. and Munoz-Blanco, J. FaQR, required for the biosynthesis of the strawberry flavor compound 4-hydroxy-2,5-dimethyl-3(2H)-furanone, encodes an enone oxidoreductase. Plant Cell 18 (2006) 1023–1037. [DOI] [PMID: 16517758]
2.	Klein, D., Fink, B., Arold, B., Eisenreich, W. and Schwab, W. Functional characterization of enone oxidoreductases from strawberry and tomato fruit. J. Agric. Food Chem. 55 (2007) 6705–6711. [DOI] [PMID: 17636940]
3.	Schiefner, A., Sinz, Q., Neumaier, I., Schwab, W. and Skerra, A. Structural basis for the enzymatic formation of the key strawberry flavor compound 4-hydroxy-2,5-dimethyl-3(2H)-furanone. J. Biol. Chem. 288 (2013) 16815–16826. [DOI] [PMID: 23589283]
4.	Uehara, K., Watanabe, J., Mogi, Y. and Tsukioka, Y. Identification and characterization of an enzyme involved in the biosynthesis of the 4-hydroxy-2(or 5)-ethyl-5(or 2)-methyl-3(2H)-furanone in yeast. J. Biosci. Bioeng. 123 (2017) 333–341. [DOI] [PMID: 27865643]

[EC 1.3.1.105 created 2013]

1.3.1.106

Accepted name:

cobalt-precorrin-6A reductase

Reaction:

cobalt-precorrin-6B + NAD⁺ = cobalt-precorrin-6A + NADH + H⁺

For diagram of anaerobic corrin biosynthesis (part 2), click here

Other name(s):

cbiJ (gene name)

Systematic name:

cobalt-precorrin-6B:NAD⁺ oxidoreductase

Comments:

The enzyme, which participates in the anaerobic (early cobalt insertion) pathway of adenosylcobalamin biosynthesis, catalyses the reduction of the double bond between C-18 and C-19 of cobalt-precorrin-6A. The enzyme from the bacterium Bacillus megaterium has no activity with NADPH. See EC 1.3.1.54, precorrin-6A reductase, for the corresponding enzyme that participates in the aerobic cobalamin biosynthesis pathway.

Links to other databases:

References:

1.	Kim, W., Major, T.A. and Whitman, W.B. Role of the precorrin 6-X reductase gene in cobamide biosynthesis in Methanococcus maripaludis. Archaea 1 (2005) 375–384. [PMID: 16243778]
2.	Moore, S.J., Lawrence, A.D., Biedendieck, R., Deery, E., Frank, S., Howard, M.J., Rigby, S.E. and Warren, M.J. Elucidation of the anaerobic pathway for the corrin component of cobalamin (vitamin B₁₂). Proc. Natl. Acad. Sci. USA 110 (2013) 14906–14911. [DOI] [PMID: 23922391]

[EC 1.3.1.106 created 2014]

1.3.1.107

Accepted name:

sanguinarine reductase

Reaction:

(1) dihydrosanguinarine + NAD(P)⁺ = sanguinarine + NAD(P)H + H⁺
(2) dihydrochelirubine + NAD(P)⁺ = chelirubine + NAD(P)H + H⁺

For diagram of chelirubine, macarpine and sanguinarine biosynthesis, click here

Glossary:

sanguinarine = 13-methyl-2H,10H-[1,3]dioxolo[4,5-i][1,3]dioxolo[4′,5′:4,5]benzo[1,2-c]phenanthridinium
dihydrosanguinarine = 13-methyl-13,14-dihydro-2H,10H-[1,3]dioxolo[4,5-i][1,3]dioxolo[4′,5′:4,5]benzo[1,2-c]phenanthridine
chelirubine = 5-methoxy-13-methyl-2H,10H-[1,3]dioxolo[4,5-i][1,3]dioxolo[4′,5′:4,5]benzo[1,2-c]phenanthridinium
dihydrochelirubine = 5-methoxy-13-methyl-13,14-dihydro-2H,10H-[1,3]dioxolo[4,5-i][1,3]dioxolo[4′,5′:4,5]benzo[1,2-c]phenanthridinium

Systematic name:

dihydrosanguinarine:NAD(P)⁺ oxidoreductase

Comments:

The enzyme, purified from the California poppy (Eschscholzia californica), is involved in detoxifying the phytoalexin sanguinarine produced by poppy itself (cf. EC 1.5.3.12, dihydrobenzophenanthridine oxidase), when it binds to the cell wall of the poppy cell. The reaction with NADPH is up to three times faster than that with NADH at low concentrations (<10 uM) of the dinucleotide. At higher concentrations the reaction with NADPH is inhibited but not that with NADH [1].

Links to other databases:

References:

1.	Weiss, D., Baumert, A., Vogel, M. and Roos, W. Sanguinarine reductase, a key enzyme of benzophenanthridine detoxification. Plant Cell Environ. 29 (2006) 291–302. [DOI] [PMID: 17080644]
2.	Vogel, M., Lawson, M., Sippl, W., Conrad, U. and Roos, W. Structure and mechanism of sanguinarine reductase, an enzyme of alkaloid detoxification. J. Biol. Chem. 285 (2010) 18397–18406. [DOI] [PMID: 20378534]

[EC 1.3.1.107 created 2014]

1.3.1.108

Accepted name:

caffeoyl-CoA reductase

Reaction:

3-(3,4-dihydroxyphenyl)propanoyl-CoA + 2 NAD⁺ + 2 reduced ferredoxin [iron-sulfur] cluster = (2E)-3-(3,4-dihydroxyphenyl)prop-2-enoyl-CoA + 2 NADH + 2 oxidized ferredoxin [iron-sulfur] cluster

Glossary:

(2E)-3-(3,4-dihydroxyphenyl)prop-2-enoyl-CoA = (2E)-3-(3,4-dihydroxyphenyl)acryloyl-CoA = trans-caffeoyl-CoA
3-(3,4-dihydroxyphenyl)propanoyl-CoA = hydrocaffeoyl-CoA

Other name(s):

electron-bifurcating caffeoyl-CoA reductase; caffeoyl-CoA reductase-Etf complex; hydrocaffeoyl-CoA:NAD⁺,ferredoxin oxidoreductase

Systematic name:

3-(3,4-dihydroxyphenyl)propanoyl-CoA:NAD⁺,ferredoxin oxidoreductase

Comments:

The enzyme, characterized from the bacterium Acetobacterium woodii, contains two [4Fe-4S] clusters and FAD. The enzyme couples the endergonic ferredoxin reduction with NADH as reductant to the exergonic reduction of caffeoyl-CoA with the same reductant. It uses the mechanism of electron bifurcation to overcome the steep energy barrier in ferredoxin reduction. It also reduces 4-coumaroyl-CoA and feruloyl-CoA.

Links to other databases:

References:

1.	Bertsch, J., Parthasarathy, A., Buckel, W. and Muller, V. An electron-bifurcating caffeyl-CoA reductase. J. Biol. Chem. 288 (2013) 11304–11311. [DOI] [PMID: 23479729]

[EC 1.3.1.108 created 2015]

1.3.1.109

Accepted name:

butanoyl-CoA dehydrogenase complex (NAD⁺, ferredoxin)

Reaction:

butanoyl-CoA + 2 NAD⁺ + 2 reduced ferredoxin [iron-sulfur] cluster = (E)-but-2-enoyl-CoA + 2 NADH + 2 oxidized ferredoxin [iron-sulfur] cluster

Glossary:

(E)-but-2-enoyl-CoA = crotonyl-CoA

Other name(s):

bifurcating butyryl-CoA dehydrogenase; butyryl-CoA dehydrogenase/Etf complex; Etf-Bcd complex; bifurcating butanoyl-CoA dehydrogenase; butanoyl-CoA dehydrogenase/Etf complex; butanoyl-CoA dehydrogenase (NAD⁺, ferredoxin)

Systematic name:

butanoyl-CoA:NAD⁺, ferredoxin oxidoreductase

Comments:

The enzyme is a complex of a flavin-containing dehydrogenase component (Bcd) and an electron-transfer flavoprotein dimer (EtfAB). The enzyme complex, isolated from the bacteria Acidaminococcus fermentans and butanoate-producing Clostridia species, couples the exergonic reduction of (E)-but-2-enoyl-CoA to butanoyl-CoA by NADH to the endergonic reduction of ferredoxin by NADH, using electron bifurcation to overcome the steep energy barrier in ferredoxin reduction.

Links to other databases:

References:

1.	Li, F., Hinderberger, J., Seedorf, H., Zhang, J., Buckel, W. and Thauer, R.K. Coupled ferredoxin and crotonyl coenzyme A (CoA) reduction with NADH catalyzed by the butyryl-CoA dehydrogenase/Etf complex from Clostridium kluyveri. J. Bacteriol. 190 (2008) 843–850. [DOI] [PMID: 17993531]
2.	Aboulnaga el,-H., Pinkenburg, O., Schiffels, J., El-Refai, A., Buckel, W. and Selmer, T. Effect of an oxygen-tolerant bifurcating butyryl coenzyme A dehydrogenase/electron-transferring flavoprotein complex from Clostridium difficile on butyrate production in Escherichia coli. J. Bacteriol. 195 (2013) 3704–3713. [DOI] [PMID: 23772070]
3.	Chowdhury, N.P., Mowafy, A.M., Demmer, J.K., Upadhyay, V., Koelzer, S., Jayamani, E., Kahnt, J., Hornung, M., Demmer, U., Ermler, U. and Buckel, W. Studies on the mechanism of electron bifurcation catalyzed by electron transferring flavoprotein (Etf) and butyryl-CoA dehydrogenase (Bcd) of Acidaminococcus fermentans. J. Biol. Chem. 289 (2014) 5145–5157. [DOI] [PMID: 24379410]
4.	Chowdhury, N.P., Kahnt, J. and Buckel, W. Reduction of ferredoxin or oxygen by flavin-based electron bifurcation in Megasphaera elsdenii. FEBS J. 282 (2015) 3149–3160. [DOI] [PMID: 25903584]

[EC 1.3.1.109 created 2015, modified 2021]

1.3.1.110

Transferred entry:

lactate dehydrogenase (NAD⁺, ferredoxin). Now EC 1.1.1.436, lactate dehydrogenase (NAD⁺,ferredoxin)

[EC 1.3.1.110 created 2015, deleted 2022]

1.3.1.111

Accepted name:

geranylgeranyl-bacteriochlorophyllide a reductase

Reaction:

bacteriochlorophyll a + 3 NADP⁺ = geranylgeranyl bacteriochlorophyllide a + 3 NADPH + 3 H⁺

For diagram of bacteriochlorophyl a biosynthesis, click here

Other name(s):

geranylgeranyl-bacteriopheophytin reductase; bchP (gene name)

Systematic name:

bacteriochlorophyll-a:NADP⁺ oxidoreductase (geranylgeranyl-reducing)

Comments:

The enzyme catalyses the successive reduction of the geranylgeraniol esterifying group to phytol, reducing three out of four double bonds, and transforming geranylgeranyl bacteriochlorophyllide a via dihydrogeranylgeranyl bacteriochlorophyllide a and tetrahydrogeranylgeranyl bacteriochlorophyllide a to bacteriochlorophyll a. The enzyme can also accept the pheophytin derivative geranylgeranyl bacteriopheophytin, converting it to bacteriopheophytin a.

Links to other databases:

References:

1.	Bollivar, D.W., Wang, S., Allen, J.P. and Bauer, C.E. Molecular genetic analysis of terminal steps in bacteriochlorophyll a biosynthesis: characterization of a Rhodobacter capsulatus strain that synthesizes geranylgeraniol-esterified bacteriochlorophyll a. Biochemistry 33 (1994) 12763–12768. [PMID: 7947681]
2.	Addlesee, H.A. and Hunter, C.N. Physical mapping and functional assignment of the geranylgeranyl-bacteriochlorophyll reductase gene, bchP, of Rhodobacter sphaeroides. J. Bacteriol. 181 (1999) 7248–7255. [PMID: 10572128]
3.	Addlesee, H.A. and Hunter, C.N. Rhodospirillum rubrum possesses a variant of the bchP gene, encoding geranylgeranyl-bacteriopheophytin reductase. J. Bacteriol. 184 (2002) 1578–1586. [DOI] [PMID: 11872709]
4.	Harada, J., Miyago, S., Mizoguchi, T., Azai, C., Inoue, K., Tamiaki, H. and Oh-oka, H. Accumulation of chlorophyllous pigments esterified with the geranylgeranyl group and photosynthetic competence in the CT2256-deleted mutant of the green sulfur bacterium Chlorobium tepidum. Photochem Photobiol Sci 7 (2008) 1179–1187. [DOI] [PMID: 18846281]

[EC 1.3.1.111 created 2016]

1.3.1.112

Accepted name:

anthocyanidin reductase [(2S)-flavan-3-ol-forming]

Reaction:

(1) a (2S,3R)-flavan-3-ol + 2 NADP⁺ = an anthocyanidin with a 3-hydroxy group + 2 NADPH + H⁺
(2) a (2S,3S)-flavan-3-ol + 2 NADP⁺ = an anthocyanidin with a 3-hydroxy group + 2 NADPH + H⁺

Systematic name:

(2S)-flavan-3-ol:NAD(P)⁺ oxidoreductase

Comments:

The enzyme, characterized from Vitis vinifera (grape), participates in the flavonoid biosynthesis pathway. It catalyses the double reduction of anthocyanidins, producing a mixture of (2S,3S)- and (2S,3R)-flavan-3-ols. The enzyme catalyses sequential hydride transfers to C-2 and C-4, respectively. Epimerization at C-3 is achieved by tautomerization that occurs between the two hydride transfers. cf. EC 1.3.1.77, anthocyanidin reductase [(2R,3R)-flavan-3-ol-forming].

Links to other databases:

References:

1.	Gargouri, M., Manigand, C., Mauge, C., Granier, T., Langlois d'Estaintot, B., Cala, O., Pianet, I., Bathany, K., Chaudiere, J. and Gallois, B. Structure and epimerase activity of anthocyanidin reductase from Vitis vinifera. Acta Crystallogr. D Biol. Crystallogr. 65 (2009) 989–1000. [DOI] [PMID: 19690377]
2.	Gargouri, M., Chaudiere, J., Manigand, C., Mauge, C., Bathany, K., Schmitter, J.M. and Gallois, B. The epimerase activity of anthocyanidin reductase from Vitis vinifera and its regiospecific hydride transfers. Biol. Chem. 391 (2010) 219–227. [DOI] [PMID: 20030585]

[EC 1.3.1.112 created 2016]

1.3.1.113

Accepted name:

(4-alkanoyl-5-oxo-2,5-dihydrofuran-3-yl)methyl phosphate reductase

Reaction:

a [(3S,4R)-4-alkanoyl-5-oxooxolan-3-yl]methyl phosphate + NADP⁺ = a (4-alkanoyl-5-oxo-2,5-dihydrofuran-3-yl)methyl phosphate + NADPH + H⁺

Other name(s):

bprA (gene name); scbC (gene name)

Systematic name:

[(3S,4R)-4-alkanoyl-5-oxooxolan-3-yl]methyl-phosphate:NADP⁺ oxidoreductase

Comments:

The enzyme, characterized from the bacteria Streptomyces griseus and Streptomyces coelicolor, is involved in the biosynthesis of γ-butyrolactone autoregulators that control secondary metabolism and morphological development in Streptomyces bacteria.

Links to other databases:

References:

1.	Kato, J.Y., Funa, N., Watanabe, H., Ohnishi, Y. and Horinouchi, S. Biosynthesis of γ-butyrolactone autoregulators that switch on secondary metabolism and morphological development in Streptomyces. Proc. Natl. Acad. Sci. USA 104 (2007) 2378–2383. [DOI] [PMID: 17277085]
2.	Biarnes-Carrera, M., Lee, C.K., Nihira, T., Breitling, R. and Takano, E. Orthogonal regulatory circuits for Escherichia coli based on the γ-butyrolactone system of Streptomyces coelicolor. ACS Synth. Biol. 7 (2018) 1043–1055. [PMID: 29510026]

[EC 1.3.1.113 created 2017]

1.3.1.114

Accepted name:

3-dehydro-bile acid Δ^4,6-reductase

Reaction:

(1) 3-oxocholan-24-oyl-CoA + NAD⁺ = 3-oxochol-4-en-24-oyl-CoA + NADH + H⁺
(2) 3-oxochol-4-en-24-oyl-CoA + NAD⁺ = 3-oxochol-4,6-dien-24-oyl-CoA + NADH + H⁺
(3) 12α-hydroxy-3-oxocholan-24-oyl-CoA + NAD⁺ = 12α-hydroxy-3-oxochol-4-en-24-oyl-CoA + NADH + H⁺
(4) 12α-hydroxy-3-oxochol-4-en-24-oyl-CoA + NAD⁺ = 12α-hydroxy-3-oxochol-4,6-dien-24-oyl-CoA + NADH + H⁺

Other name(s):

baiN (gene name)

Systematic name:

3-oxocholan-24-oyl-CoA Δ^4,6-oxidoreductase

Comments:

Contains flavin. The enzyme, characterized from the bacterium Clostridium scindens, participates in the bile acid 7α-dehydroxylation pathway. The enzyme catalyses two subsequent reductions of the double bonds within the bile acid A/B rings, following 7α-dehydration.

Links to other databases:

References:

Harris, S.C., Devendran, S., Alves, J.MP., Mythen, S.M., Hylemon, P.B. and Ridlon, J.M. Identification of a gene encoding a flavoprotein involved in bile acid metabolism by the human gut bacterium Clostridium scindens ATCC 35704. Biochim. Biophys. Acta 1863 (2018) 276–283. [DOI] [PMID: 29217478]

[EC 1.3.1.114 created 2018]

1.3.1.115

Accepted name:

3-oxocholoyl-CoA 4-desaturase

Reaction:

(1) 7α,12α-dihydroxy-3-oxochol-24-oyl-CoA + NAD⁺ = 7α,12α-dihydroxy-3-oxochol-4-en-24-oyl-CoA + NADH + H⁺
(2) 7α-hydroxy-3-oxochol-24-oyl-CoA + NAD⁺ = 7α-hydroxy-3-oxochol-4-en-24-oyl-CoA + NADH + H⁺

Glossary:

7α,12α-dihydroxy-3-oxochol-24-oyl-CoA = 3-oxocholoyl-CoA
7α-hydroxy-3-oxochol-24-oyl-CoA = 3-oxochenodeoxycholoyl-CoA

Other name(s):

baiCD (gene name); 3-oxo-choloyl-CoA dehydrogenase

Systematic name:

3-oxocholoyl-CoA Δ⁴-oxidoreductase

Comments:

Contains flavin. The enzyme, characterized from the bacterium Clostridium scindens, participates in the bile acid 7α-dehydroxylation pathway. The enzyme catalyses the stereo-specific oxidation of its substrates and has no activity with the 7β anomers. cf. EC 1.3.1.116, 7β-hydroxy-3-oxochol-24-oyl-CoA 4-desaturase.

Links to other databases:

References:

1.	Kang, D.J., Ridlon, J.M., Moore, D.R., 2nd, Barnes, S. and Hylemon, P.B. Clostridium scindens baiCD and baiH genes encode stereo-specific 7α/7β-hydroxy-3-oxo-Δ⁴-cholenoic acid oxidoreductases. Biochim. Biophys. Acta 1781 (2008) 16–25. [PMID: 18047844]

[EC 1.3.1.115 created 2018]

1.3.1.116

Accepted name:

7β-hydroxy-3-oxochol-24-oyl-CoA 4-desaturase

Reaction:

7β-hydroxy-3-oxochol-24-oyl-CoA + NAD⁺ = 7β-hydroxy-3-oxochol-4-en-24-oyl-CoA + NADH + H⁺

Other name(s):

baiH (gene name)

Systematic name:

7β-hydroxy-3-oxochol-24-oyl-CoA Δ⁴-oxidoreductase

Comments:

Contains FAD and FMN. The enzyme, characterized from the bacterium Clostridium scindens, participates in the bile acid 7α-dehydroxylation pathway. The enzyme catalyses the stereo-specific oxidation of its substrate and has no activity with the 7α anomer. cf. EC 1.3.1.115, 3-oxocholoyl-CoA 4-desaturase.

Links to other databases:

References:

1.	Baron, S.F. and Hylemon, P.B. Expression of the bile acid-inducible NADH:flavin oxidoreductase gene of Eubacterium sp. VPI 12708 in Escherichia coli. Biochim. Biophys. Acta 1249 (1995) 145–154. [PMID: 7599167]
2.	Franklund, C.V., Baron, S.F. and Hylemon, P.B. Characterization of the baiH gene encoding a bile acid-inducible NADH:flavin oxidoreductase from Eubacterium sp. strain VPI 12708. J. Bacteriol. 175 (1993) 3002–3012. [PMID: 8491719]
3.	Kang, D.J., Ridlon, J.M., Moore, D.R., 2nd, Barnes, S. and Hylemon, P.B. Clostridium scindens baiCD and baiH genes encode stereo-specific 7α/7β-hydroxy-3-oxo-Δ⁴-cholenoic acid oxidoreductases. Biochim. Biophys. Acta 1781 (2008) 16–25. [PMID: 18047844]

[EC 1.3.1.116 created 2018]

1.3.1.117

Accepted name:

hydroxycinnamoyl-CoA reductase

Reaction:

(1) dihydro-4-coumaroyl-CoA + NADP⁺ = trans-4-coumaroyl-CoA + NADPH + H⁺
(2) dihydroferuloyl-CoA + NADP⁺ = trans-feruloyl-CoA + NADPH + H⁺

For diagram of phloretin biosynthesis, click here

Glossary:

trans-4-coumaroyl-CoA = (E)-3-(4-hydroxyphenyl)prop-2-enoyl-CoA
trans-feruloyl-CoA = (E)-3-(4-hydroxy-3-methoxyphenyl)prop-2-enoyl-CoA
dihydro-4-coumaroyl-CoA = 3-(4-hydroxyphenyl)propanoyl-CoA
dihydroferuloyl-CoA = 3-(4-hydroxy-3-methoxyphenyl)propanoyl-CoA

Other name(s):

MdHCDBR; hydroxycinnamoyl-CoA double bond reductase

Systematic name:

dihydro-4-coumaroyl-CoA:NADP⁺ 2,3-oxidoreductase

Comments:

Isolated from Malus X domestica (apple). Involved in dihydrochalcone biosynthesis.

Links to other databases:

References:

Ibdah, M., Berim, A., Martens, S., Valderrama, A.L.H., Palmieri, L., Lewinsohn, E. and Gang, D.R. Identification and cloning of an NADPH-dependant hydroxycinnamoyl-CoA double bond reductase involved in dihydrochalcone formation in Malus X domestica Borkh. Phytochemistry 107 (2014) 24-31. [DOI] [PMID: 25152451]

[EC 1.3.1.117 created 2018]

1.3.1.118

Accepted name:

meromycolic acid enoyl-[acyl-carrier-protein] reductase

Reaction:

a meromycolyl-[acyl-carrier protein] + NAD⁺ = a trans-Δ²-meromycolyl-[acyl-carrier protein] + NADH + H⁺

Glossary:

meromycolic acids are one of the two precursors of the mycolic acids produced by Mycobacteria. They consist of a long chain typically of 50–60 carbons, which is functionalized by different groups.

Other name(s):

inhA (gene name)

Systematic name:

meromycolyl-[acyl-carrier protein]:NAD⁺ oxidoreductase

Comments:

InhA is a component of the fatty acid synthase (FAS) II system of Mycobacterium tuberculosis, catalysing an enoyl-[acyl-carrier-protein] reductase step. The enzyme acts on very long and unsaturated fatty acids that form the meromycolic component of mycolic acids. It extends FASI-derived C₂₀ fatty acids to form C₆₀ to C₉₀ mycolic acids. The enzyme, which forms a homotetramer, is the target of the preferred antitubercular drug isoniazid.

Links to other databases:

References:

1.	Quemard, A., Sacchettini, J.C., Dessen, A., Vilcheze, C., Bittman, R., Jacobs, W.R., Jr. and Blanchard, J.S. Enzymatic characterization of the target for isoniazid in Mycobacterium tuberculosis. Biochemistry 34 (1995) 8235–8241. [PMID: 7599116]
2.	Rozwarski, D.A., Vilcheze, C., Sugantino, M., Bittman, R. and Sacchettini, J.C. Crystal structure of the Mycobacterium tuberculosis enoyl-ACP reductase, InhA, in complex with NAD⁺ and a C₁₆ fatty acyl substrate. J. Biol. Chem. 274 (1999) 15582–15589. [PMID: 10336454]
3.	Marrakchi, H., Laneelle, G. and Quemard, A. InhA, a target of the antituberculous drug isoniazid, is involved in a mycobacterial fatty acid elongation system, FAS-II. Microbiology 146 (2000) 289–296. [PMID: 10708367]
4.	Vilcheze, C., Morbidoni, H.R., Weisbrod, T.R., Iwamoto, H., Kuo, M., Sacchettini, J.C. and Jacobs, W.R., Jr. Inactivation of the inhA-encoded fatty acid synthase II (FASII) enoyl-acyl carrier protein reductase induces accumulation of the FASI end products and cell lysis of Mycobacterium smegmatis. J. Bacteriol. 182 (2000) 4059–4067. [PMID: 10869086]
5.	Gurvitz, A., Hiltunen, J.K. and Kastaniotis, A.J. Function of heterologous Mycobacterium tuberculosis InhA, a type 2 fatty acid synthase enzyme involved in extending C₂₀ fatty acids to C⁶⁰-to-C₉₀ mycolic acids, during de novo lipoic acid synthesis in Saccharomyces cerevisiae. Appl. Environ. Microbiol. 74 (2008) 5078–5085. [PMID: 18552191]
6.	Chollet, A., Mourey, L., Lherbet, C., Delbot, A., Julien, S., Baltas, M., Bernadou, J., Pratviel, G., Maveyraud, L. and Bernardes-Genisson, V. Crystal structure of the enoyl-ACP reductase of Mycobacterium tuberculosis (InhA) in the apo-form and in complex with the active metabolite of isoniazid pre-formed by a biomimetic approach. J. Struct. Biol. 190 (2015) 328–337. [PMID: 25891098]

[EC 1.3.1.118 created 2018]

1.3.1.119

Accepted name:

chlorobenzene dihydrodiol dehydrogenase

Reaction:

(1R,2R)-3-chlorocyclohexa-3,5-diene-1,2-diol + NAD⁺ = 3-chlorocatechol + NADH + H⁺

Other name(s):

tecB (gene name)

Systematic name:

(1R,2R)-3-chlorocyclohexa-3,5-diene-1,2-diol:NAD⁺ oxidoreductase

Comments:

This bacterial enzyme can transform various dihydrodiols of chlorobenzenes into the respective catechols, including the dihydrodiols of mono-, di-, tri-, and tetra-chlorinated benzenes. It also accepts the dihydrodiols of various chlorotoluenes. Substrates for the enzyme are generated by the broad spectrum EC 1.14.12.26, chlorobenzene dioxygenase.

Links to other databases:

References:

1.	Spiess, E. and Gorisch, H. Purification and characterization of chlorobenzene cis-dihydrodiol dehydrogenase from Xanthobacter flavus 14p1. Arch. Microbiol. 165 (1996) 201–205. [PMID: 8599538]
2.	Pollmann, K., Beil, S. and Pieper, D.H. Transformation of chlorinated benzenes and toluenes by Ralstonia sp. strain PS12 tecA (tetrachlorobenzene dioxygenase) and tecB (chlorobenzene dihydrodiol dehydrogenase) gene products. Appl. Environ. Microbiol. 67 (2001) 4057–4063. [PMID: 11526005]
3.	Pollmann, K., Wray, V. and Pieper, D.H. Chloromethylmuconolactones as critical metabolites in the degradation of chloromethylcatechols: recalcitrance of 2-chlorotoluene. J. Bacteriol. 187 (2005) 2332–2340. [PMID: 15774876]

[EC 1.3.1.119 created 2018]

1.3.1.120

Accepted name:

cyclohexane-1-carbonyl-CoA reductase (NADP⁺)

Reaction:

cyclohexane-1-carbonyl-CoA + NADP⁺ = cyclohex-1-ene-1-carbonyl-CoA + NADPH + H⁺

Other name(s):

1-cyclohexenylcarbonyl-CoA reductase (ambiguous); chcA (gene name)

Systematic name:

cyclohexane-1-carbonyl-CoA:NADP⁺ 1-oxidoreductase

Comments:

The enzyme, characterized from the bacterium Streptomyces collinus, is involved in a pathway that transforms shikimate to cyclohexane-1-carbonyl-CoA by a series of dehydration and double-bond reduction steps. Most of the steps in this process occur with the carboxylic acid activated as a coenzyme A thioester. The enzyme catalyses three steps in this pathway, also acting on (3R,4R)-3,4-dihydroxycyclohexa-1,5-diene-1-carbonyl-CoA and (5S)-5-hydroxycyclohex-1-ene-1-carbonyl-CoA.

Links to other databases:

References:

1.	Reynolds, K.A., Wang, P., Fox, K.M., Speedie, M.K., Lam, Y. and Floss, H.G. Purification and characterization of a novel enoyl coenzyme A reductase from Streptomyces collinus. J. Bacteriol. 174 (1992) 3850–3854. [PMID: 1597409]
2.	Wang, P., Denoya, C.D., Morgenstern, M.R., Skinner, D.D., Wallace, K.K., Digate, R., Patton, S., Banavali, N., Schuler, G., Speedie, M.K. and Reynolds, K.A. Cloning and characterization of the gene encoding 1-cyclohexenylcarbonyl coenzyme A reductase from Streptomyces collinus. J. Bacteriol. 178 (1996) 6873–6881. [PMID: 8955309]

[EC 1.3.1.120 created 2019]

1.3.1.121

Accepted name:

4-amino-4-deoxyprephenate dehydrogenase

Reaction:

4-amino-4-deoxyprephenate + NAD⁺ = 3-(4-aminophenyl)pyruvate + CO₂ + NADH + H⁺

Other name(s):

cmlC (gene name); papC (gene name)

Systematic name:

4-amino-4-deoxyprephenate:NAD⁺ oxidoreductase (decarboxylating)

Comments:

The enzyme, characterized from the bacteria Streptomyces venezuelae and Streptomyces pristinaespiralis, participates in the biosynthesis of the antibiotics chloramphenicol and pristinamycin IA, respectively. cf. EC 1.3.1.12, prephenate dehydrogenase.

Links to other databases:

References:

1.	Blanc, V., Gil, P., Bamas-Jacques, N., Lorenzon, S., Zagorec, M., Schleuniger, J., Bisch, D., Blanche, F., Debussche, L., Crouzet, J. and Thibaut, D. Identification and analysis of genes from Streptomyces pristinaespiralis encoding enzymes involved in the biosynthesis of the 4-dimethylamino-L-phenylalanine precursor of pristinamycin I. Mol. Microbiol. 23 (1997) 191–202. [PMID: 9044253]
2.	He, J., Magarvey, N., Piraee, M. and Vining, L.C. The gene cluster for chloramphenicol biosynthesis in Streptomyces venezuelae ISP5230 includes novel shikimate pathway homologues and a monomodular non-ribosomal peptide synthetase gene. Microbiology 147 (2001) 2817–2829. [PMID: 11577160]

[EC 1.3.1.121 created 2019]

1.3.1.122

Accepted name:

(S)-8-oxocitronellyl enol synthase

Reaction:

(S)-8-oxocitronellyl enol + NAD(P)⁺ = (6E)-8-oxogeranial + NAD(P)H + H⁺

For diagram of secologanin biosynthesis, click here

Glossary:

(S)-8-oxocitronellyl enol = (2E,6S,7E)-8-hydroxy-2,6-dimethylocta-2,7-dienal

Other name(s):

CrISY; 8-oxogeranial:NAD(P)⁺ oxidoreductase (cyclizing, cis-trans-nepetalactol forming); iridoid synthase (incorrect)

Systematic name:

(S)-8-oxocitronellyl enol:NAD(P)⁺ oxidoreductase

Comments:

Isolated from the plants Catharanthus roseus, Olea europaea (common olive), and several Nepeta species. The enzyme reduces 8-oxogeranial, generating an unstable product that is subsequently cyclized into several possible products, either non-enzymically or by dedicated cyclases. The products, known as iridoids, are involved in the biosynthesis of many indole alkaloids. cf. EC 1.3.1.123, 7-epi-iridoid synthase.

Links to other databases:

References:

1.	Geu-Flores, F., Sherden, N.H., Courdavault, V., Burlat, V., Glenn, W.S., Wu, C., Nims, E., Cui, Y. and O'Connor, S.E. An alternative route to cyclic terpenes by reductive cyclization in iridoid biosynthesis. Nature 492 (2012) 138–142. [DOI] [PMID: 23172143]
2.	Hu, Y., Liu, W., Malwal, S.R., Zheng, Y., Feng, X., Ko, T.P., Chen, C.C., Xu, Z., Liu, M., Han, X., Gao, J., Oldfield, E. and Guo, R.T. Structures of iridoid synthase from Catharanthus roseus with bound NAD⁺, NADPH, or NAD⁺/10-oxogeranial: Reaction mechanisms. Angew. Chem. Int. Ed. Engl. 54 (2015) 15478–15482. [PMID: 26768532]
3.	Alagna, F., Geu-Flores, F., Kries, H., Panara, F., Baldoni, L., O'Connor, S.E. and Osbourn, A. Identification and characterization of the iridoid synthase involved in oleuropein biosynthesis in olive (Olea europaea) fruits. J. Biol. Chem. 291 (2016) 5542–5554. [PMID: 26709230]
4.	Qin, L., Zhu, Y., Ding, Z., Zhang, X., Ye, S. and Zhang, R. Structure of iridoid synthase in complex with NADP⁺/8-oxogeranial reveals the structural basis of its substrate specificity. J. Struct. Biol. 194 (2016) 224–230. [PMID: 26868105]
5.	Sherden, N.H., Lichman, B., Caputi, L., Zhao, D., Kamileen, M.O., Buell, C.R. and O'Connor, S.E. Identification of iridoid synthases from Nepeta species: Iridoid cyclization does not determine nepetalactone stereochemistry. Phytochemistry 145 (2018) 48–56. [PMID: 29091815]
6.	Lichman, B.R., Kamileen, M.O., Titchiner, G.R., Saalbach, G., Stevenson, C.EM., Lawson, D.M. and O'Connor, S.E. Uncoupled activation and cyclization in catmint reductive terpenoid biosynthesis. Nat. Chem. Biol. 15 (2019) 71–79. [PMID: 30531909]
7.	Lichman, B.R., O'Connor, S.E. and Kries, H. Biocatalytic strategies towards [4+2] cycloadditions. Chemistry 25 (2019) 6864–6877. [PMID: 30664302]

[EC 1.3.1.122 created 2013 as EC 1.3.1.99, part transferred 2019 to EC 1.3.1.122]

1.3.1.123

Accepted name:

8-oxogeranial reductase

Reaction:

(R)-8-oxocitronellyl enol + NADP⁺ = (6E)-8-oxogeranial + NADPH + H⁺

Glossary:

(R)-8-oxocitronellyl enol = (2E,6R,7E)-8-hydroxy-2,6-dimethylocta-2,7-dienal

Other name(s):

AmISY

Systematic name:

(R)-8-oxocitronellyl enol:NADP⁺ oxidoreductase

Comments:

The enzyme, characterized from the plant Antirrhinum majus (snapdragon), is involved in biosynthesis of 7-epi-iridoids such as antirrhinoside. The enzyme catalyses the stereospecific reduction of 8-oxogeranial, forming an unstable product that in the absence of additional cylases undergoes spontaneous cyclization to (–)-cis,trans-nepetalactol. cf. EC 1.3.1.122, (S)-8-oxocitronellyl enol synthase.

Links to other databases:

References:

1.	Kries, H., Kellner, F., Kamileen, M.O. and O'Connor, S.E. Inverted stereocontrol of iridoid synthase in snapdragon. J. Biol. Chem. 292 (2017) 14659–14667. [PMID: 28701463]
2.	Lichman, B.R., O'Connor, S.E. and Kries, H. Biocatalytic strategies towards [4+2] cycloadditions. Chemistry 25 (2019) 6864–6877. [PMID: 30664302]

[EC 1.3.1.123 created 2019]

1.3.1.124

Accepted name:

2,4-dienoyl-CoA reductase [(3E)-enoyl-CoA-producing]

Reaction:

(1) a (3E)-3-enoyl-CoA + NADP⁺ = a (2E,4E)-2,4-dienoyl-CoA + NADPH + H⁺
(2) a (3E)-3-enoyl-CoA + NADP⁺ = a (2E,4Z)-2,4-dienoyl-CoA + NADPH + H⁺

Other name(s):

SPS19 (gene name); DECR1 (gene name); DECR2 (gene name); Δ²,Δ⁴-dienoyl-CoA reductase (ambiguous)

Systematic name:

(3E)-3-enoyl-CoA:NADP⁺ 4-oxidoreductase

Comments:

This enzyme, characterized from eukaryotic organisms, catalyses the reduction of either (2E,4E)-2,4-dienoyl-CoA or (2E,4Z)-2,4-dienoyl-CoA to (3E)-3-enoyl-CoA. The best substrates for the enzyme from bovine liver have a chain-length of 8 or 10 carbons. Mammals possess both mitochondrial and peroxisomal variants of this enzyme. cf. EC 1.3.1.34, 2,4-dienoyl-CoA reductase [(2E)-enoyl-CoA-producing].

Links to other databases: