The Enzyme Database

Displaying entries 51-100 of 1240.

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EC 3.2.1.133     Relevance: 100%
Accepted name: glucan 1,4-α-maltohydrolase
Reaction: hydrolysis of (1→4)-α-D-glucosidic linkages in polysaccharides so as to remove successive α-maltose residues from the non-reducing ends of the chains
Other name(s): maltogenic α-amylase; 1,4-α-D-glucan α-maltohydrolase
Systematic name: 4-α-D-glucan α-maltohydrolase
Comments: Acts on starch and related polysaccharides and oligosaccharides. The product is α-maltose; cf. EC 3.2.1.2 β-amylase.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 160611-47-2
References:
1.  Diderichsen, B. and Christiansen, L. Cloning of a maltogenic α-amylase from Bacillus stearothermophilus. FEMS Microbiol. Lett. 56 (1988) 53–59.
2.  Outtrup, H. and Norman, B.E. Properties and application of a thermostable maltogenic amylase produced by a strain of Bacillus modified by recombinant-DNA techniques. Stärke 36 (1984) 405–411.
[EC 3.2.1.133 created 1992, modified 1999]
 
 
EC 2.4.1.342     Relevance: 99.6%
Accepted name: α-maltose-1-phosphate synthase
Reaction: ADP-α-D-glucose + α-D-glucose-1-phosphate = ADP + α-maltose-1-phosphate
Glossary: maltose = α-D-glucopyranosyl-(1→4)-D-glucose
Other name(s): glgM (gene name)
Systematic name: ADP-α-D-glucose:α-D-glucose-1-phosphate 4-α-D-glucosyltransferase (configuration-retaining)
Comments: The enzyme, found in Mycobacteria, can also use UDP-α-D-glucose with much lower catalytic efficiency.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB
References:
1.  Koliwer-Brandl, H., Syson, K., van de Weerd, R., Chandra, G., Appelmelk, B., Alber, M., Ioerger, T.R., Jacobs, W.R., Jr., Geurtsen, J., Bornemann, S. and Kalscheuer, R. Metabolic network for the biosynthesis of intra- and extracellular α-glucans required for virulence of Mycobacterium tuberculosis. PLoS Pathog. 12 (2016) e1005768. [DOI] [PMID: 27513637]
[EC 2.4.1.342 created 2016]
 
 
EC 2.8.2.37     Relevance: 99.4%
Accepted name: trehalose 2-sulfotransferase
Reaction: 3′-phosphoadenylyl sulfate + α,α-trehalose = adenosine 3′,5′-bisphosphate + 2-O-sulfo-α,α-trehalose
Glossary: 2-O-sulfo-α,α-trehalose = trehalose 2-sulfate = α-D-glucopyranosyl 2-O-sulfo-α-D-glucopyranoside
Other name(s): Stf0 sulfotransferase; 3′-phosphoadenylyl-sulfate:α,α-trehalose 2-sulfotransferase
Systematic name: 3′-phosphoadenylyl-sulfate:α,α-trehalose 2-sulfonotransferase
Comments: The sulfation of trehalose in the bacterium Mycobacterium tuberculosis is required for the biosynthesis of sulfolipid-1.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc
References:
1.  Mougous, J.D., Petzold, C.J., Senaratne, R.H., Lee, D.H., Akey, D.L., Lin, F.L., Munchel, S.E., Pratt, M.R., Riley, L.W., Leary, J.A., Berger, J.M. and Bertozzi, C.R. Identification, function and structure of the mycobacterial sulfotransferase that initiates sulfolipid-1 biosynthesis. Nat. Struct. Mol. Biol. 11 (2004) 721–729. [DOI] [PMID: 15258569]
2.  Pi, N., Hoang, M.B., Gao, H., Mougous, J.D., Bertozzi, C.R. and Leary, J.A. Kinetic measurements and mechanism determination of Stf0 sulfotransferase using mass spectrometry. Anal. Biochem. 341 (2005) 94–104. [DOI] [PMID: 15866533]
[EC 2.8.2.37 created 2014]
 
 
EC 2.4.1.167     Relevance: 98.9%
Accepted name: sucrose 6F-α-galactosyltransferase
Reaction: UDP-α-D-galactose + sucrose = UDP + 6F-α-D-galactosylsucrose
Other name(s): uridine diphosphogalactose-sucrose 6F-α-galactosyltransferase; UDPgalactose:sucrose 6fru-α-galactosyltransferase; sucrose 6F-α-galactotransferase; UDP-galactose:sucrose 6F-α-D-galactosyltransferase
Systematic name: UDP-α-D-galactose:sucrose 6F-α-D-galactosyltransferase
Comments: The enzyme is involved in the synthesis of the trisaccharide planteose and higher analogues in the seeds of Plantago and Sesamum species.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number: 92480-04-1
References:
1.  Hopf, H., Spanfelner, M. and Kandler, O. Planteose synthesis in seeds of Sesamum indicum L. Z. Pflanzenphysiol. 114 (1984) 485–492.
[EC 2.4.1.167 created 1989]
 
 
EC 1.14.13.49      
Transferred entry: (S)-limonene 7-monooxygenase. Now classified as EC 1.14.14.52, (S)-limonene 7-monooxygenase
[EC 1.14.13.49 created 1992, modified 2003, deleted 2017]
 
 
EC 3.2.1.139     Relevance: 98.5%
Accepted name: α-glucuronidase
Reaction: an α-D-glucuronoside + H2O = an alcohol + D-glucuronate
Other name(s): α-glucosiduronase
Systematic name: α-D-glucosiduronate glucuronohydrolase
Comments: Considerable differences in the specificities of the enzymes from different fungi for α-D-glucosiduronates have been reported. Activity is also found in the snail.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 37259-81-7
References:
1.  Puls, J. α-Glucuronidases in the hydrolysis of wood xylans. In: Visser, J., Kusters van Someren, M.A., Beldman, G. and Voragen, A.G.J. (Ed.), Xylans and Xylanases, Elsevier, Amsterdam, 1992, pp. 213–224.
2.  Uchida, H., Nanri, T., Kawabata, Y., Kusakabe, I., Murakami, K. Purification and characterization of intracellular α-glucuronidase from Aspergillus niger. Biosci. Biotechnol. Biochem. 56 (1992) 1608–1615.
[EC 3.2.1.139 created 1999]
 
 
EC 2.4.1.362     Relevance: 98.3%
Accepted name: α-(1→3) branching sucrase
Reaction: sucrose + a (1→6)-α-D-glucan = D-fructose + a (1→6)-α-D-glucan containing a (1→3)-α-D-glucose branch
Other name(s): branching sucrase A; BRS-A; brsA (gene name)
Systematic name: sucrose:(1→6)-α-D-glucan 3-α-D-[(1→3)-α-D-glucosyl]-transferase
Comments: The enzyme from Leuconostoc spp. is responsible for producing α-(1→3) branches in α-(1→6) glucans by transferring the glucose residue from fructose to a 3-hydroxyl group of a glucan.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc
References:
1.  Vuillemin, M., Claverie, M., Brison, Y., Severac, E., Bondy, P., Morel, S., Monsan, P., Moulis, C. and Remaud-Simeon, M. Characterization of the first α-(1→3) branching sucrases of the GH70 family. J. Biol. Chem. 291 (2016) 7687–7702. [PMID: 26763236]
2.  Moulis, C., Andre, I. and Remaud-Simeon, M. GH13 amylosucrases and GH70 branching sucrases, atypical enzymes in their respective families. Cell. Mol. Life Sci. 73 (2016) 2661–2679. [PMID: 27141938]
[EC 2.4.1.362 created 2019]
 
 
EC 2.4.1.259     Relevance: 97.9%
Accepted name: dolichyl-P-Man:Man6GlcNAc2-PP-dolichol α-1,2-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→3)-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-α-D-GlcNAc-diphosphodolichol = 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-(1→4)-β-D-GlcNAc-(1→4)-α-D-GlcNAc-diphosphodolichol + dolichyl phosphate
For diagram of dolichyltetradecasaccharide biosynthesis, click here
Other name(s): ALG9; ALG9 α1,2 mannosyltransferase; dolichylphosphomannose-dependent ALG9 mannosyltransferase; ALG9 mannosyltransferase; Dol-P-Man:Man6GlcNAc2-PP-Dol α-1,2-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→3)-D-Man-α-(1→6)]-D-Man-β-(1→4)-D-GlcNAc-β-(1→4)-D-GlcNAc-diphosphodolichol α-1,2-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→3)-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-α-D-GlcNAc-diphosphodolichol 2-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. ALG9 mannosyltransferase catalyses the addition of two different α-1,2-mannose residues - the addition of α-1,2-mannose to Man6GlcNAc2-PP-Dol (EC 2.4.1.259) and the addition of α-1,2-mannose to Man8GlcNAc2-PP-Dol (EC 2.4.1.261).
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc
References:
1.  Vleugels, W., Keldermans, L., Jaeken, J., Butters, T.D., Michalski, J.C., Matthijs, G. and Foulquier, F. Quality control of glycoproteins bearing truncated glycans in an ALG9-defective (CDG-IL) patient. Glycobiology 19 (2009) 910–917. [DOI] [PMID: 19451548]
2.  Cipollo, J.F. and Trimble, R.B. The accumulation of Man(6)GlcNAc(2)-PP-dolichol in the Saccharomyces cerevisiae Δalg9 mutant reveals a regulatory role for the Alg3p α1,3-Man middle-arm addition in downstream oligosaccharide-lipid and glycoprotein glycan processing. J. Biol. Chem. 275 (2000) 4267–4277. [DOI] [PMID: 10660594]
3.  Frank, C.G. and Aebi, M. ALG9 mannosyltransferase is involved in two different steps of lipid-linked oligosaccharide biosynthesis. Glycobiology 15 (2005) 1156–1163. [DOI] [PMID: 15987956]
[EC 2.4.1.259 created 1976 as EC 2.4.1.130, part transferred 2011 to EC 2.4.1.259, modified 2012]
 
 
EC 3.2.1.50     Relevance: 97.5%
Accepted name: α-N-acetylglucosaminidase
Reaction: Hydrolysis of terminal non-reducing N-acetyl-D-glucosamine residues in N-acetyl-α-D-glucosaminides
Other name(s): α-acetylglucosaminidase; N-acetyl-α-D-glucosaminidase; N-acetyl-α-glucosaminidase; α-D-2-acetamido-2-deoxyglucosidase
Systematic name: α-N-acetyl-D-glucosaminide N-acetylglucosaminohydrolase
Comments: Hydrolyses UDP-N-acetylglucosamine.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 37288-40-7
References:
1.  von Figura, K. Human α-N-acetylglucosaminidase. 1. Purification and properties. Eur. J. Biochem. 80 (1977) 523–533. [PMID: 411658]
2.  von Figura, K. Human α-N-acetylglucosaminidase. 2. Activity towards natural substrates and multiple recognition forms. Eur. J. Biochem. 80 (1977) 535–542. [DOI] [PMID: 923593]
3.  Weissmann, B., Rowen, G., Marshall, J. and Friederici, D. Mammalian α-acetylglucosaminidase. Enzymic properties, tissue distribution, and intracellular localization. Biochemistry 6 (1967) 207–214. [PMID: 4291567]
4.  Werries, E., Wollek, E., Gottschalk, A. and Buddecke, E. Separation of N-acetyl-α-glucosaminidase and N-acetyl-α-galactosaminidase from ox spleen. Cleavage of the O-glycosidic linkage between carbohydrate and polypeptide in ovine and bovine submaxillary glycoprotein by N-acetyl-α-galactosaminidase. Eur. J. Biochem. 10 (1969) 445–449. [DOI] [PMID: 5348072]
[EC 3.2.1.50 created 1972]
 
 
EC 3.2.1.59     Relevance: 96.7%
Accepted name: glucan endo-1,3-α-glucosidase
Reaction: Endohydrolysis of (1→3)-α-D-glucosidic linkages in isolichenin, pseudonigeran and nigeran
Other name(s): endo-1,3-α-glucanase; mutanase; endo-(1→3)-α-glucanase; cariogenase; cariogenanase; endo-1,3-α-D-glucanase; 1,3(1,3;1,4)-α-D-glucan 3-glucanohydrolase
Systematic name: 3-α-D-glucan 3-glucanohydrolase
Comments: Products from pseudonigeran (1,3-α-D-glucan) are nigerose and α-D-glucose.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 9075-84-7
References:
1.  Hasegawa, S., Nordin, J.H. and Kirkwood, S. Enzymes that hydrolyze fungal cell wall polysaccharides. I. Purification and properties of an endo-α-D-(1-3)-glucanase from Trichoderma. J. Biol. Chem. 244 (1969) 5460–5470. [PMID: 5388595]
[EC 3.2.1.59 created 1972]
 
 
EC 3.2.1.49     Relevance: 96.6%
Accepted name: α-N-acetylgalactosaminidase
Reaction: Cleavage of non-reducing α-(1→3)-N-acetylgalactosamine residues from human blood group A and AB mucin glycoproteins, Forssman hapten and blood group A lacto series glycolipids
Other name(s): α-acetylgalactosaminidase; N-acetyl-α-D-galactosaminidase; N-acetyl-α-galactosaminidase; α-NAGAL; α-NAGA; α-GalNAcase
Systematic name: α-N-acetyl-D-galactosaminide N-acetylgalactosaminohydrolase
Comments: The human lysosomal enzyme is involved in the degradation of blood type A epitope.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 9075-63-2
References:
1.  Asfaw, B., Schindler, D., Ledvinova, J., Cerny, B., Smid, F. and Conzelmann, E. Degradation of blood group A glycolipid A-6-2 by normal and mutant human skin fibroblasts. J. Lipid Res. 39 (1998) 1768–1780. [PMID: 9741689]
2.  Zhu, A., Monahan, C., Wang, Z.K. and Goldstein, J. Expression, purification, and characterization of recombinant α-N-acetylgalactosaminidase produced in the yeast Pichia pastoris. Protein Expr. Purif. 8 (1996) 456–462. [DOI] [PMID: 8954893]
3.  Clark, N.E. and Garman, S.C. The 1.9 Å structure of human α-N-acetylgalactosaminidase: The molecular basis of Schindler and Kanzaki diseases. J. Mol. Biol. 393 (2009) 435–447. [DOI] [PMID: 19683538]
4.  Hoskins, L.C., Boulding, E.T. and Larson, G. Purification and characterization of blood group A-degrading isoforms of α-N-acetylgalactosaminidase from Ruminococcus torques strain IX-70. J. Biol. Chem. 272 (1997) 7932–7939. [DOI] [PMID: 9065462]
5.  Harun-Or-Rashid, M., Matsuzawa, T., Satoh, Y., Shiraishi, T., Ando, M., Sadik, G. and Uda, Y. Purification and characterization of α-N-acetylgalactosaminidases I and II from the starfish Asterina amurensis. Biosci. Biotechnol. Biochem. 74 (2010) 256–261. [DOI] [PMID: 20139603]
6.  Weignerova, L., Filipi, T., Manglova, D. and Kren, V. Induction, purification and characterization of α-N-acetylgalactosaminidase from Aspergillus niger. Appl. Microbiol. Biotechnol. 79 (2008) 769–774. [DOI] [PMID: 18443780]
7.  Ashida, H., Tamaki, H., Fujimoto, T., Yamamoto, K. and Kumagai, H. Molecular cloning of cDNA encoding α-N-acetylgalactosaminidase from Acremonium sp. and its expression in yeast. Arch. Biochem. Biophys. 384 (2000) 305–310. [DOI] [PMID: 11368317]
[EC 3.2.1.49 created 1972, modified 2011]
 
 
EC 3.2.1.116     Relevance: 96.2%
Accepted name: glucan 1,4-α-maltotriohydrolase
Reaction: Hydrolysis of (1→4)-α-D-glucosidic linkages in amylaceous polysaccharides, to remove successive maltotriose residues from the non-reducing chain ends
Other name(s): exo-maltotriohydrolase; maltotriohydrolase; 1,4-α-D-glucan maltotriohydrolase
Systematic name: 4-α-D-glucan maltotriohydrolase
Comments: cf. EC 3.2.1.2 (β-amylase), EC 3.2.1.60 (glucan 1,4-α-maltotetraohydrolase) and EC 3.2.1.98 (glucan 1,4-α-maltohexaosidase). The products have the α-configuration.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number: 91273-84-6
References:
1.  Nakakuki, T., Azuma, K. and Kainuma, K. Action patterns of various exo-amylases and the anomeric configurations of their products. Carbohydr. Res. 128 (1984) 297–310.
[EC 3.2.1.116 created 1989]
 
 
EC 3.2.1.82     Relevance: 96.1%
Accepted name: exo-poly-α-digalacturonosidase
Reaction: [(1→4)-α-D-galacturonosyl]n + H2O = α-D-galacturonosyl-(1→4)-D-galacturonate + [(1→4)-α-D-galacturonosyl]n-2
Other name(s): pehX (gene name); poly(1,4-α-D-galactosiduronate) digalacturonohydrolase; exopolygalacturonosidase (misleading); poly[(1→4)-α-D-galactosiduronate] digalacturonohydrolase; exo-poly-α-galacturonosidase
Systematic name: poly[(1→4)-α-D-galactosiduronate] non-reducing-end-digalacturonohydrolase
Comments: The enzyme, characterized from bacteria, hydrolyses the second α-1,4-glycosidic bond from the non-reducing end of polygalacturonate, releasing digalacturonate.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number: 37288-58-7
References:
1.  Hasegawa, H. and Nagel, C.W. Isolation of an oligogalacturonate hydrolase from a Bacillus species. Arch. Biochem. Biophys. 124 (1968) 513–520. [DOI] [PMID: 5661621]
2.  Hatanaka, C. and Ozawa, J. Enzymic degradation of pectic acid. XIII. New exopolygalacturonase producing digalacturonic acid from pectic acid. J. Agric. Chem. Soc. Jpn.. 43 (1968) 764–772.
3.  Hatanaka, C. and Ozawa, J. Ber. des O'Hara Inst. 15 (1971) 47.
4.  He, S.Y. and Collmer, A. Molecular cloning, nucleotide sequence, and marker exchange mutagenesis of the exo-poly-α-D-galacturonosidase-encoding pehX gene of Erwinia chrysanthemi EC16. J. Bacteriol. 172 (1990) 4988–4995. [PMID: 2168372]
[EC 3.2.1.82 created 1972, modified 2019]
 
 
EC 3.2.1.99     Relevance: 95.7%
Accepted name: arabinan endo-1,5-α-L-arabinanase
Reaction: Endohydrolysis of (1→5)-α-arabinofuranosidic linkages in (1→5)-arabinans
Other name(s): endo-1,5-α-L-arabinanase; endo-α-1,5-arabanase; endo-arabanase; 1,5-α-L-arabinan 1,5-α-L-arabinanohydrolase; arabinan endo-1,5-α-L-arabinosidase (misleading)
Systematic name: 5-α-L-arabinan 5-α-L-arabinanohydrolase
Comments: Acts best on linear 1,5-α-L-arabinan. Also acts on branched arabinan, but more slowly.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 75432-96-1
References:
1.  Kaji, A. and Saheki, T. Endo-arabinanase from Bacillus subtilis F-11. Biochim. Biophys. Acta 410 (1975) 354–360. [DOI] [PMID: 1096]
2.  Weinstein, L. and Albersheim, P. Structure of plant cell walls. IX. Purification and partial characterization of a wall-degrading endo-arabinase and an arabinosidase from Bacillus subtilis. Plant Physiol. 63 (1979) 425–432. [PMID: 16660741]
3.  Flipphi, M.J., Panneman, H., van der Veen, P., Visser, J. and de Graaff, L.H. Molecular cloning, expression and structure of the endo-1,5-α-L-arabinase gene of Aspergillus niger. Appl. Microbiol. Biotechnol. 40 (1993) 318–326. [PMID: 7764386]
4.  Leal, T.F. and de Sa-Nogueira, I. Purification, characterization and functional analysis of an endo-arabinanase (AbnA) from Bacillus subtilis. FEMS Microbiol. Lett. 241 (2004) 41–48. [DOI] [PMID: 15556708]
[EC 3.2.1.99 created 1981, modified 2011]
 
 
EC 2.4.1.347     Relevance: 95.5%
Accepted name: α,α-trehalose-phosphate synthase (ADP-forming)
Reaction: ADP-α-D-glucose + D-glucose 6-phosphate = ADP + α,α-trehalose 6-phosphate
Other name(s): otsA (gene name); ADP-glucose—glucose-phosphate glucosyltransferase
Systematic name: ADP-α-D-glucose:D-glucose-6-phosphate 1-α-D-glucosyltransferase (configuration-retaining)
Comments: The enzyme has been reported from the yeast Saccharomyces cerevisiae and from mycobacteria. The enzyme from Mycobacterium tuberculosis can also use UDP-α-D-glucose, but the activity with ADP-α-D-glucose, which is considered the main substrate in vivo, is higher.
Links to other databases: BRENDA, EXPASY, GTD, KEGG, MetaCyc, PDB, CAS registry number: 9030-07-3
References:
1.  Ferreira, J.C., Thevelein, J.M., Hohmann, S., Paschoalin, V.M., Trugo, L.C. and Panek, A.D. Trehalose accumulation in mutants of Saccharomyces cerevisiae deleted in the UDPG-dependent trehalose synthase-phosphatase complex. Biochim. Biophys. Acta 1335 (1997) 40–50. [DOI] [PMID: 9133641]
2.  Pan, Y.T., Carroll, J.D. and Elbein, A.D. Trehalose-phosphate synthase of Mycobacterium tuberculosis. Cloning, expression and properties of the recombinant enzyme. Eur. J. Biochem. 269 (2002) 6091–6100. [DOI] [PMID: 12473104]
3.  Asencion Diez, M.D., Demonte, A.M., Syson, K., Arias, D.G., Gorelik, A., Guerrero, S.A., Bornemann, S. and Iglesias, A.A. Allosteric regulation of the partitioning of glucose-1-phosphate between glycogen and trehalose biosynthesis in Mycobacterium tuberculosis. Biochim. Biophys. Acta 1850 (2015) 13–21. [DOI] [PMID: 25277548]
[EC 2.4.1.347 created 2017]
 
 
EC 3.2.1.210     Relevance: 95.1%
Accepted name: endoplasmic reticulum Man8GlcNAc2 1,2-α-mannosidase
Reaction: Man8GlcNAc2-[protein] (isomer 8A1,2,3B1,3) + H2O = Man7GlcNAc2-[protein] (isomer 7A1,2,3B3) + D-mannopyranose
Glossary: Man8GlcNAc2-[protein] (isomer 8A1,2,3B1,3) = {α-D-Man-(1→2)-α-D-Man-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→3)-[α-D-Man-(1→2)-α-D-Man-(1→6)]-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-α-D-GlcNAc}-N-Asn-[protein]
Man7GlcNAc2-[protein] (isomer 7A1,2,3B3) = {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)]-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-α-D-GlcNAc}-N-Asn-[protein]
Other name(s): MNL1 (gene name)
Systematic name: Man8GlcNAc2-[protein] 2-α-mannohydrolase (configuration-inverting)
Comments: In yeast this activity is catalysed by a dedicated enzyme that processes unfolded protein-bound Man8GlcNAc2 N-glycans within the endoplasmic reticulum to Man7GlcNAc2. The exposed α-1,6-linked mannose residue in the product enables the recognition by the YOS9 lectin, targeting the proteins for degradation. In mammalian cells this activity is part of the regular processing of N-glycosylated proteins, and is not associated with protein degradation. It is carried out by EC 3.2.1.113, Golgi mannosyl-oligosaccharide 1,2-α-mannosidase. The names of the isomers listed here are based on a nomenclature system proposed by Prien et al [5].
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc
References:
1.  Nakatsukasa, K., Nishikawa, S., Hosokawa, N., Nagata, K. and Endo, T. Mnl1p, an α -mannosidase-like protein in yeast Saccharomyces cerevisiae, is required for endoplasmic reticulum-associated degradation of glycoproteins. J. Biol. Chem. 276 (2001) 8635–8638. [PMID: 11254655]
2.  Jakob, C.A., Bodmer, D., Spirig, U., Battig, P., Marcil, A., Dignard, D., Bergeron, J.J., Thomas, D.Y. and Aebi, M. Htm1p, a mannosidase-like protein, is involved in glycoprotein degradation in yeast. EMBO Rep. 2 (2001) 423–430. [PMID: 11375935]
3.  Quan, E.M., Kamiya, Y., Kamiya, D., Denic, V., Weibezahn, J., Kato, K. and Weissman, J.S. Defining the glycan destruction signal for endoplasmic reticulum-associated degradation. Mol. Cell 32 (2008) 870–877. [PMID: 19111666]
4.  Clerc, S., Hirsch, C., Oggier, D.M., Deprez, P., Jakob, C., Sommer, T. and Aebi, M. Htm1 protein generates the N-glycan signal for glycoprotein degradation in the endoplasmic reticulum. J. Cell Biol. 184 (2009) 159–172. [PMID: 19124653]
5.  Prien, J.M., Ashline, D.J., Lapadula, A.J., Zhang, H. and Reinhold, V.N. The high mannose glycans from bovine ribonuclease B isomer characterization by ion trap MS. J. Am. Soc. Mass Spectrom. 20 (2009) 539–556. [DOI] [PMID: 19181540]
6.  Chantret, I., Kodali, V.P., Lahmouich, C., Harvey, D.J. and Moore, S.E. Endoplasmic reticulum-associated degradation (ERAD) and free oligosaccharide generation in Saccharomyces cerevisiae. J. Biol. Chem. 286 (2011) 41786–41800. [PMID: 21979948]
[EC 3.2.1.210 created 2019]
 
 
EC 3.2.1.163     Relevance: 94.9%
Accepted name: 1,6-α-D-mannosidase
Reaction: Hydrolysis of the (1→6)-linked α-D-mannose residues in α-D-Manp-(1→6)-D-Manp
Systematic name: (1→6)-α-mannosyl α-D-mannohydrolase
Comments: The enzyme is specific for (1→6)-linked mannobiose and has no activity towards any other linkages, or towards p-nitrophenyl-α-D-mannopyranoside or baker’s yeast mannan. It is strongly inhibited by Mn2+ but does not require Ca2+ or any other metal cofactor for activity.
Links to other databases: BRENDA, EXPASY
References:
1.  Athanasopoulos, V.I., Niranjan, K. and Rastall, R.A. The production, purification and characterisation of two novel α-D-mannosidases from Aspergillus phoenicis. Carbohydr. Res. 340 (2005) 609–617. [DOI] [PMID: 15721331]
[EC 3.2.1.163 created 2007]
 
 
EC 2.4.1.140     Relevance: 94.9%
Accepted name: alternansucrase
Reaction: Transfers alternately an α-D-glucosyl residue from sucrose to the 6-position and the 3-position of the non-reducing terminal residue of an α-D-glucan, thus producing a glucan having alternating α-(1→6)- and α-(1→3)-linkages
Other name(s): sucrose-1,6(3)-α-glucan 6(3)-α-glucosyltransferase; sucrose:1,6-, 1,3-α-D-glucan 3-α- and 6-α-D-glucosyltransferase; sucrose:1,6(1,3)-α-D-glucan 6(3)-α-D-glucosyltransferase
Systematic name: sucrose:(1→6)[(1→3)]-α-D-glucan 6(3)-α-D-glucosyltransferase
Comments: The glucansucrases transfer a D-glucosyl residue from sucrose to a glucan chain. They are classified based on the linkage by which they attach the transferred residue. In some cases, in which the enzyme forms more than one linkage type, classification relies on the relative proportion of the linkages that are generated. This enzyme forms both α(1→3) and α(1→6) linkages in approximately equal amounts by alternating the linkage type. cf. EC 2.4.1.125, sucrose—1,6-α-glucan 3(6)-α-glucosyltransferase.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 100630-46-4
References:
1.  Cote, G.L. and Robyt, J.F. Isolation and partial characterization of an extracellular glucansucrase from Leuconostoc mesenteroides NRRL B-1355 that synthesizes an alternating (1→6), (1→3)-α-D-glucan. Carbohydr. Res. 101 (1982) 57–74. [DOI] [PMID: 7060056]
2.  Arguello-Morales, M.A., Remaud-Simeon, M., Pizzut, S., Sarcabal, P., Willemot, R. and Monsan, P. Sequence analysis of the gene encoding alternansucrase, a sucrose glucosyltransferase from Leuconostoc mesenteroides NRRL B-1355. FEMS Microbiol. Lett. 182 (2000) 81–85. [PMID: 10612736]
[EC 2.4.1.140 created 1984, modified 2003]
 
 
EC 3.2.1.137     Relevance: 94.9%
Accepted name: mannan exo-1,2-1,6-α-mannosidase
Reaction: Hydrolysis of (1→2)-α-D- and (1→6)-α-D- linkages in yeast mannan, releasing D-mannose
Other name(s): exo-1,2-1,6-α-mannosidase; 1,2-1,6-α-D-mannan D-mannohydrolase
Systematic name: (1→2)-(1→6)-α-D-mannan D-mannohydrolase
Comments: Mannose residues linked α-D-1,3- are also released, but very slowly.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number: 123175-72-4
References:
1.  Takegawa, K., Miki, S., Jikibara, T. and Iwahara, S. Purification and characterization of exo-α-D-mannosidase from a Cellulomonas sp. Biochim. Biophys. Acta 991 (1989) 431–437.
[EC 3.2.1.137 created 1992]
 
 
EC 2.7.1.235     Relevance: 94.8%
Accepted name: lipopolysaccharide core heptose(I) kinase
Reaction: ATP + an α-Hep-(1→3)-α-Hep-(1→5)-[α-Kdo-(2→4)]-α-Kdo-(2→6)-[lipid A] = ADP + an α-Hep-(1→3)-4-O-phospho-α-Hep-(1→5)-[α-Kdo-(2→4)]-α-Kdo-(2→6)-[lipid A]
Glossary: Lipid A is a lipid component of the lipopolysaccharides (LPS) of Gram-negative bacteria. It usually consists of two glucosamine units connected by a β(1→6) bond and decorated with four to seven acyl chains and up to two phosphate groups.
Hep = L-glycero-β-D-manno-heptose
Other name(s): WaaP; RfaP
Systematic name: ATP:an α-Hep-(1→3)-α-Hep-(1→5)-[α-Kdo-(2→4)]-α-Kdo-(2→6)-[lipid A] heptoseI 4-O-phosphotransferase
Comments: The enzyme catalyses the phosphorylation of L-glycero-D-manno-heptose I (the first heptose added to the lipid, Hep I) in the biosynthesis of the inner core oligosaccharide of the lipopolysaccharide (endotoxin) of some Gram-negative bacteria.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc
References:
1.  Yethon, J.A. and Whitfield, C. Purification and characterization of WaaP from Escherichia coli, a lipopolysaccharide kinase essential for outer membrane stability. J. Biol. Chem. 276 (2001) 5498–5504. [DOI] [PMID: 11069912]
2.  Zhao, X. and Lam, J.S. WaaP of Pseudomonas aeruginosa is a novel eukaryotic type protein-tyrosine kinase as well as a sugar kinase essential for the biosynthesis of core lipopolysaccharide. J. Biol. Chem. 277 (2002) 4722–4730. [DOI] [PMID: 11741974]
3.  Kreamer, N.NK., Chopra, R., Caughlan, R.E., Fabbro, D., Fang, E., Gee, P., Hunt, I., Li, M., Leon, B.C., Muller, L., Vash, B., Woods, A.L., Stams, T., Dean, C.R. and Uehara, T. Acylated-acyl carrier protein stabilizes the Pseudomonas aeruginosa WaaP lipopolysaccharide heptose kinase. Sci. Rep. 8:14124 (2018). [DOI] [PMID: 30237436]
[EC 2.7.1.235 created 2021]
 
 
EC 2.4.1.183     Relevance: 94.7%
Accepted name: α-1,3-glucan synthase
Reaction: UDP-glucose + [α-D-glucosyl-(1→3)]n = UDP + [α-D-glucosyl-(1→3)]n+1
Other name(s): uridine diphosphoglucose-1,3-α-glucan glucosyltransferase; 1,3-α-D-glucan synthase; UDP-glucose:α-D-(1-3)-glucan 3-α-D-glucosyltransferase
Systematic name: UDP-glucose:α-D-(1→3)-glucan 3-α-D-glucosyltransferase
Comments: A glucan primer is needed to begin the reaction, which brings about elongation of the glucan chains.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number: 113478-38-9
References:
1.  Andoh, M., Yamashita, Y., Shigeoka, T., Hanada, N. and Takehara, T. [Extension of the length of glucan chain by 1,3-α-D-glucansynthase from Streptococcus mutans serotype.] Koku Eisei Gakkai Zasshi 37 (1987) 516–517.
[EC 2.4.1.183 created 1990]
 
 
EC 2.4.1.245     Relevance: 94.1%
Accepted name: α,α-trehalose synthase
Reaction: NDP-α-D-glucose + D-glucose = α,α-trehalose + NDP
Glossary: NDP = a nucleoside diphosphate
Other name(s): trehalose synthase; trehalose synthetase; UDP-glucose:glucose 1-glucosyltransferase; TreT; PhGT; ADP-glucose:D-glucose 1-α-D-glucosyltransferase
Systematic name: NDP-α-D-glucose:D-glucose 1-α-D-glucosyltransferase
Comments: Requires Mg2+ for maximal activity [1]. The enzyme-catalysed reaction is reversible [1]. In the reverse direction to that shown above, the enzyme is specific for α,α-trehalose as substrate, as it cannot use α- or β-paranitrophenyl glucosides, maltose, sucrose, lactose or cellobiose [1]. While the enzymes from the thermophilic bacterium Rubrobacter xylanophilus and the hyperthermophilic archaeon Pyrococcus horikoshii can use ADP-, UDP- and GDP-α-D-glucose to the same extent [2,3], that from the hyperthermophilic archaeon Thermococcus litoralis has a marked preference for ADP-α-D-glucose [1] and that from the hyperthermophilic archaeon Thermoproteus tenax has a marked preference for UDP-α-D-glucose [4].
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB
References:
1.  Qu, Q., Lee, S.J. and Boos, W. TreT, a novel trehalose glycosyltransferring synthase of the hyperthermophilic archaeon Thermococcus litoralis. J. Biol. Chem. 279 (2004) 47890–47897. [DOI] [PMID: 15364950]
2.  Ryu, S.I., Park, C.S., Cha, J., Woo, E.J. and Lee, S.B. A novel trehalose-synthesizing glycosyltransferase from Pyrococcus horikoshii: molecular cloning and characterization. Biochem. Biophys. Res. Commun. 329 (2005) 429–436. [DOI] [PMID: 15737605]
3.  Nobre, A., Alarico, S., Fernandes, C., Empadinhas, N. and da Costa, M.S. A unique combination of genetic systems for the synthesis of trehalose in Rubrobacter xylanophilus: properties of a rare actinobacterial TreT. J. Bacteriol. 190 (2008) 7939–7946. [DOI] [PMID: 18835983]
4.  Kouril, T., Zaparty, M., Marrero, J., Brinkmann, H. and Siebers, B. A novel trehalose synthesizing pathway in the hyperthermophilic Crenarchaeon Thermoproteus tenax: the unidirectional TreT pathway. Arch. Microbiol. 190 (2008) 355–369. [DOI] [PMID: 18483808]
[EC 2.4.1.245 created 2008, modified 2013]
 
 
EC 3.2.1.84     Relevance: 94%
Accepted name: glucan 1,3-α-glucosidase
Reaction: Hydrolysis of terminal (1→3)-α-D-glucosidic links in (1→3)-α-D-glucans
Other name(s): exo-1,3-α-glucanase; glucosidase II; 1,3-α-D-glucan 3-glucohydrolase
Systematic name: 3-α-D-glucan 3-glucohydrolase
Comments: Does not act on nigeran.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 9073-99-8
References:
1.  Zonneveld, B.J.M. A new type of enzyme, and exo-splitting α-1,3 glucanase from non-induced cultures of Aspergillus nidulans. Biochim. Biophys. Acta 258 (1972) 541–547. [DOI] [PMID: 4622000]
[EC 3.2.1.84 created 1972]
 
 
EC 2.4.99.25     Relevance: 94%
Accepted name: lipopolysaccharide heptosyltransferase III
Reaction: ADP-L-glycero-β-D-manno-heptose + an α-Hep-(1→3)-4-O-phospho-α-Hep-(1→5)-[α-Kdo-(2→4)]-α-Kdo-(2→6)-[lipid A] = ADP + an α-Hep-(1→7)-α-Hep-(1→3)-4-O-phospho-α-Hep-(1→5)-[α-Kdo-(2→4)]-α-Kdo-(2→6)-[lipid A]
Glossary: Lipid A is a lipid component of the lipopolysaccharides (LPS) of Gram-negative bacteria. It consists of two glucosamine units connected by a β(1→6) bond and decorated with four to seven acyl chains and up to two phosphate groups.
Hep = L-glycero-D-manno-heptose
Other name(s): waaQ (gene name); rfaQ (gene name)
Systematic name: ADP-L-glycero-β-D-manno-heptose:an α-Hep-(1→3)-4-O-phospho-α-Hep-(1→5)-[α-Kdo-(2→4)]-α-Kdo-(2→6)-[lipid A] heptoseI 7-α-heptosyltransferase
Comments: The enzyme catalyses a glycosylation step in the biosynthesis of the inner core oligosaccharide of the lipopolysaccharide (endotoxin) of some Gram-negative bacteria.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc
References:
1.  Mudapaka, J. and Taylor, E.A. Cloning and characterization of the Escherichia coli heptosyltransferase III: Exploring substrate specificity in lipopolysaccharide core biosynthesis. FEBS Lett. 589 (2015) 1423–1429. [DOI] [PMID: 25957775]
[EC 2.4.99.25 created 2022]
 
 
EC 2.3.1.288     Relevance: 94%
Accepted name: 2-O-sulfo trehalose long-chain-acyltransferase
Reaction: (1) stearoyl-CoA + 2-O-sulfo-α,α-trehalose = 2-O-sulfo-2′-stearoyl-α,α-trehalose + CoA
(2) palmitoyl-CoA + 2-O-sulfo-α,α-trehalose = 2-O-sulfo-2′-palmitoyl-α,α-trehalose + CoA
Other name(s): papA2 (gene name)
Systematic name: acyl-CoA:2-O-sulfo-α,α-trehalose 2′-long-chain-acyltransferase
Comments: This mycobacterial enzyme catalyses the acylation of 2-O-sulfo-α,α-trehalose at the 2′ position by a C16 or C18 fatty acyl group during the biosynthesis of mycobacterial sulfolipids.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB
References:
1.  Kumar, P., Schelle, M.W., Jain, M., Lin, F.L., Petzold, C.J., Leavell, M.D., Leary, J.A., Cox, J.S. and Bertozzi, C.R. PapA1 and PapA2 are acyltransferases essential for the biosynthesis of the Mycobacterium tuberculosis virulence factor sulfolipid-1. Proc. Natl. Acad. Sci. USA 104 (2007) 11221–11226. [PMID: 17592143]
2.  Seeliger, J.C., Holsclaw, C.M., Schelle, M.W., Botyanszki, Z., Gilmore, S.A., Tully, S.E., Niederweis, M., Cravatt, B.F., Leary, J.A. and Bertozzi, C.R. Elucidation and chemical modulation of sulfolipid-1 biosynthesis in Mycobacterium tuberculosis. J. Biol. Chem. 287 (2012) 7990–8000. [PMID: 22194604]
[EC 2.3.1.288 created 2019]
 
 
EC 2.4.1.161     Relevance: 93.9%
Accepted name: oligosaccharide 4-α-D-glucosyltransferase
Reaction: Transfers the non-reducing terminal α-D-glucose residue from a (1→4)-α-D-glucan to the 4-position of a free glucose or of a glucosyl residue at the non-reducing terminus of a (1→4)-α-D-glucan, thus bringing about the rearrangement of oligosaccharides
Other name(s): amylase III; 1,4-α-glucan:1,4-α-glucan 4-α-glucosyltransferase; 1,4-α-D-glucan:1,4-α-D-glucan 4-α-D-glucosyltransferase; α-1,4-transglucosylase
Systematic name: (1→4)-α-D-glucan:(1→4)-α-D-glucan 4-α-D-glucosyltransferase
Comments: The enzyme acts on amylose, amylopectin, glycogen and maltooligosaccharides. No detectable free glucose is formed, indicating the enzyme does not act as a hydrolase. The enzyme from the bacterium Cellvibrio japonicus has the highest activity with maltotriose as a donor, and also accepts maltose [3], while the enzyme from amoeba does not accept maltose [1,2]. Oligosaccharides with 1→6 linkages cannot function as donors, but can act as acceptors [3]. Unlike EC 2.4.1.25, 4-α-glucanotransferase, this enzyme can transfer only a single glucosyl residue.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 9000-92-4
References:
1.  Nebinger, P. Separation and characterization of four different amylases of Entamoeba histolytica. I. Purification and properties. Biol. Chem. Hoppe-Seyler 367 (1986) 161–167. [PMID: 2423097]
2.  Nebinger, P. Separation and characterization of four different amylases of Entamoeba histolytica. II. Characterization of amylases. Biol. Chem. Hoppe-Seyler 367 (1986) 169–176. [PMID: 2423098]
3.  Larsbrink, J., Izumi, A., Hemsworth, G.R., Davies, G.J. and Brumer, H. Structural enzymology of Cellvibrio japonicus Agd31B protein reveals α-transglucosylase activity in glycoside hydrolase family 31. J. Biol. Chem. 287 (2012) 43288–43299. [DOI] [PMID: 23132856]
[EC 2.4.1.161 created 1989, modified 2013]
 
 
EC 2.4.1.131     Relevance: 93.8%
Accepted name: GDP-Man:Man3GlcNAc2-PP-dolichol α-1,2-mannosyltransferase
Reaction: 2 GDP-α-D-mannose + α-D-Man-(1→3)-[α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-α-D-GlcNAc-diphosphodolichol = 2 GDP + α-D-Man-(1→2)-α-D-Man-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-α-D-GlcNAc-diphosphodolichol
For diagram of dolichyltetradecasaccharide biosynthesis, click here
Other name(s): ALG11; ALG11 mannosyltransferase; LEW3 (gene name); At2G40190 (gene name); gmd3 (gene name); galactomannan deficiency protein 3; GDP-mannose:glycolipid 1,2-α-D-mannosyltransferase; glycolipid 2-α-mannosyltransferase; GDP-mannose:glycolipid 2-α-D-mannosyltransferase; GDP-Man:Man3GlcNAc2-PP-Dol α-1,2-mannosyltransferase; GDP-α-D-mannose:D-Man-α-(1→3)-[D-Man-α-(1→6)]-D-Man-β-(1→4)-D-GlcNAc-β-(1→4)-D-GlcNAc-diphosphodolichol 2-α-D-mannosyltransferase
Systematic name: GDP-α-D-mannose:α-D-Man-(1→3)-[α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-α-D-GlcNAc-diphosphodolichol 2-α-D-mannosyltransferase (configuration-retaining)
Comments: The biosynthesis of asparagine-linked glycoproteins (N-linked protein glycosylation) utilizes a dolichyl diphosphate-linked glycosyl donor, which is assembled by the series of membrane-bound glycosyltransferases that comprise the dolichol pathway. ALG11 mannosyltransferase from Saccharomyces cerevisiae carries out two sequential steps in the formation of the lipid-linked core oligosaccharide, adding two mannose residues in α(1→2) linkages to the nascent oligosaccharide.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 74506-43-7
References:
1.  O'Reilly, M.K., Zhang, G. and Imperiali, B. In vitro evidence for the dual function of Alg2 and Alg11: essential mannosyltransferases in N-linked glycoprotein biosynthesis. Biochemistry 45 (2006) 9593–9603. [DOI] [PMID: 16878994]
2.  Absmanner, B., Schmeiser, V., Kampf, M. and Lehle, L. Biochemical characterization, membrane association and identification of amino acids essential for the function of Alg11 from Saccharomyces cerevisiae, an α1,2-mannosyltransferase catalysing two sequential glycosylation steps in the formation of the lipid-linked core oligosaccharide. Biochem. J. 426 (2010) 205–217. [DOI] [PMID: 19929855]
3.  Schutzbach, J.S., Springfield, J.D. and Jensen, J.W. The biosynthesis of oligosaccharide-lipids. Formation of an α-1,2-mannosyl-mannose linkage. J. Biol. Chem. 255 (1980) 4170–4175. [PMID: 6154707]
[EC 2.4.1.131 created 1984, modified 2011, modified 2012]
 
 
EC 3.2.1.20     Relevance: 93.7%
Accepted name: α-glucosidase
Reaction: Hydrolysis of terminal, non-reducing (1→4)-linked α-D-glucose residues with release of D-glucose
Other name(s): maltase; glucoinvertase; glucosidosucrase; maltase-glucoamylase; α-glucopyranosidase; glucosidoinvertase; α-D-glucosidase; α-glucoside hydrolase; α-1,4-glucosidase
Systematic name: α-D-glucoside glucohydrolase
Comments: This single entry covers a group of enzymes whose specificity is directed mainly towards the exohydrolysis of (1→4)-α-glucosidic linkages, and that hydrolyse oligosaccharides rapidly, relative to polysaccharide, which are hydrolysed relatively slowly, or not at all. The intestinal enzyme also hydrolyses polysaccharides, catalysing the reactions of EC 3.2.1.3 glucan 1,4-α-glucosidase and, more slowly, hydrolyses (1→6)-α-D-glucose links.
Links to other databases: BRENDA, EXPASY, GTD, KEGG, MetaCyc, PDB, CAS registry number: 9001-42-7
References:
1.  Bruni, C.B., Sica, V., Auricchio, F. and Covelli, I. Further kinetic and structural characterization of the lysosomal α-D-glucoside glucohydrolase from cattle liver. Biochim. Biophys. Acta 212 (1970) 470–477. [DOI] [PMID: 5466143]
2.  Flanagan, P.R. and Forstner, G.G. Purification of rat intestinal maltase/glucoamylase and its anomalous dissociation either by heat or by low pH. Biochem. J. 173 (1978) 553–563. [PMID: 29602]
3.  Larner, J. Other glucosidases. In: Boyer, P.D., Lardy, H. and Myrbäck, K. (Ed.), The Enzymes, 2nd edn, vol. 4, Academic Press, New York, 1960, pp. 369–378.
4.  Sivikami, S. and Radhakrishnan, A.N. Purification of rabbit intestinal glucoamylase by affinity chromatography on Sephadex G-200. Indian J. Biochem. Biophys. 10 (1973) 283–284. [PMID: 4792946]
5.  Sørensen, S.H., Norén, O., Sjöström, H. and Danielsen, E.M. Amphiphilic pig intestinal microvillus maltase/glucoamylase. Structure and specificity. Eur. J. Biochem. 126 (1982) 559–568. [DOI] [PMID: 6814909]
[EC 3.2.1.20 created 1961]
 
 
EC 2.4.1.2     Relevance: 93.7%
Accepted name: dextrin dextranase
Reaction: [(1→4)-α-D-glucosyl]n + [(1→6)-α-D-glucosyl]m = [(1→4)-α-D-glucosyl]n-1 + [(1→6)-α-D-glucosyl]m+1
Other name(s): dextrin 6-glucosyltransferase; dextran dextrinase; 1,4-α-D-glucan:1,6-α-D-glucan 6-α-D-glucosyltransferase
Systematic name: (1→4)-α-D-glucan:(1→6)-α-D-glucan 6-α-D-glucosyltransferase
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number: 9032-13-7
References:
1.  Hehre, E.J. Enzymic synthesis of polysaccharides: a biological type of polymerization. Adv. Enzymol. Relat. Subj. Biochem. 11 (1951) 297–337. [PMID: 24540594]
2.  Hehre, E.J. and Hamilton, D.M. Bacterial conversion of dextrin into a polysaccharide with the serological properties of dextran. Proc. Soc. Exp. Biol. Med. 71 (1949) 336–339. [PMID: 18136472]
3.  Hehre, E.J. and Hamilton, D.M. The biological synthesis of dextran from dextrins. J. Biol. Chem. 192 (1953) 161–174. [PMID: 14917661]
[EC 2.4.1.2 created 1961]
 
 
EC 2.4.1.43     Relevance: 93.5%
Accepted name: polygalacturonate 4-α-galacturonosyltransferase
Reaction: UDP-α-D-galacturonate + [(1→4)-α-D-galacturonosyl]n = UDP + [(1→4)-α-D-galacturonosyl]n+1
Other name(s): UDP galacturonate-polygalacturonate α-galacturonosyltransferase; uridine diphosphogalacturonate-polygalacturonate α-galacturonosyltransferase; UDP-D-galacturonate:1,4-α-poly-D-galacturonate 4-α-D-galacturonosyltransferase; UDP-D-galacturonate:(1→4)-α-poly-D-galacturonate 4-α-D-galacturonosyltransferase
Systematic name: UDP-α-D-galacturonate:(1→4)-α-poly-D-galacturonate 4-α-D-galacturonosyltransferase (configuration-retaining)
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number: 37277-53-5
References:
1.  Villemez, C.L., Swanson, A.L. and Hassid, W.Z. Properties of a polygalacturonic acid-synthesizing enzyme system from Phaseolus aureus seedlings. Arch. Biochem. Biophys. 116 (1966) 446–452. [DOI] [PMID: 5961848]
[EC 2.4.1.43 created 1972]
 
 
EC 2.4.1.82     Relevance: 93.5%
Accepted name: galactinol—sucrose galactosyltransferase
Reaction: α-D-galactosyl-(1→3)-1D-myo-inositol + sucrose = myo-inositol + raffinose
For diagram of stachyose biosynthesis, click here
Glossary: raffinose = β-D-fructofuranosyl α-D-galactopyranosyl-(1→6)-α-D-glucopyranoside
Other name(s): 1-α-D-galactosyl-myo-inositol:sucrose 6-α-D-galactosyltransferase; α-D-galactosyl-(1→3)-myo-inositol:sucrose 6-α-D-galactosyltransferase; raffinose synthase; RafS
Systematic name: α-D-galactosyl-(1→3)-1D-myo-inositol:sucrose 6-α-D-galactosyltransferase
Comments: 4-Nitrophenyl α-D-galactopyranoside can also act as donor. The enzyme also catalyses an exchange reaction between raffinose and sucrose (cf. EC 2.4.1.123, inositol 3-α-galactosyltransferase).
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 62213-45-0
References:
1.  Lehle, L. and Tanner, W. The function of myo-inositol in the biosynthesis of raffinose. Purification and characterization of galactinol:sucrose 6-galactosyltransferase from Vicia faba seeds. Eur. J. Biochem. 38 (1973) 103–110. [DOI] [PMID: 4774118]
2.  Lehle, L., Tanner, W. and Kandler, O. Myo-inositol, a cofactor in the biosynthesis of raffinose. Hoppe-Seyler's Z. Physiol. Chem. 351 (1970) 1494–1498. [PMID: 5491608]
[EC 2.4.1.82 created 1976, modified 2003]
 
 
EC 3.2.1.61     Relevance: 93.4%
Accepted name: mycodextranase
Reaction: Endohydrolysis of (1→4)-α-D-glucosidic linkages in α-D-glucans containing both (1→3)- and (1→4)-bonds
Other name(s): 1,3-1,4-α-D-glucan 4-glucanohydrolase
Systematic name: (1→3)-(1→4)-α-D-glucan 4-glucanohydrolase
Comments: Products are nigerose and 4-α-D-nigerosylglucose. No hydrolysis of α-D-glucans containing only 1,3- or 1,4-bonds.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 9047-04-5
References:
1.  Tung, K. and Nordin, J.H. Structure of the tetrasaccharide produced by the hydrolysis of nigeran by the enzyme mycodextranase. Biochim. Biophys. Acta 158 (1968) 154–156. [DOI] [PMID: 5652425]
[EC 3.2.1.61 created 1972]
 
 
EC 2.4.1.25     Relevance: 93%
Accepted name: 4-α-glucanotransferase
Reaction: Transfers a segment of a (1→4)-α-D-glucan to a new position in an acceptor, which may be glucose or a (1→4)-α-D-glucan
Other name(s): disproportionating enzyme; dextrin glycosyltransferase; D-enzyme; debranching enzyme maltodextrin glycosyltransferase; amylomaltase; dextrin transglycosylase; 1,4-α-D-glucan:1,4-α-D-glucan 4-α-D-glycosyltransferase
Systematic name: (1→4)-α-D-glucan:(1→4)-α-D-glucan 4-α-D-glycosyltransferase
Comments: This entry covers the former separate entry for EC 2.4.1.3 (amylomaltase). The plant enzyme has been termed D-enzyme. An enzymic activity of this nature forms part of the mammalian and yeast glycogen debranching system (see EC 3.2.1.33 amylo-α-1,6-glucosidase).
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 9032-09-1
References:
1.  Hehre, E.J. Enzymic synthesis of polysaccharides: a biological type of polymerization. Adv. Enzymol. Relat. Subj. Biochem. 11 (1951) 297–337. [PMID: 24540594]
2.  Lukomskaya, I.S. Synthesis of oligosaccharides with α-1,6-bonds by enzyme preparations from liver and muscle. Dokl. Akad. Nauk S.S.S.R. 129 (1959) 1172–1175. (in Russian)
3.  Pazur, J.H. and Okada, S. The isolation and mode of action of a bacterial glucanosyltransferase. J. Biol. Chem. 243 (1968) 4732–4738. [PMID: 4972097]
4.  Walker, G.J. and Whelan, W.J. Synthesis of amylose by potato D-enzyme. Nature 183 (1959) 46. [PMID: 13622683]
5.  Whelan, W.H. Enzymic explorations of the structures of starch and glycogen. Biochem. J. 122 (1971) 609–622. [PMID: 5001952]
[EC 2.4.1.25 created 1965 (EC 2.4.1.3 created 1961, incorporated 1972)]
 
 
EC 2.4.1.292     Relevance: 92.8%
Accepted name: GalNAc-α-(1→4)-GalNAc-α-(1→3)-diNAcBac-PP-undecaprenol α-1,4-N-acetyl-D-galactosaminyltransferase
Reaction: 3 UDP-N-acetyl-α-D-galactosamine + GalNAc-α-(1→4)-GalNAc-α-(1→3)-diNAcBac-PP-tritrans,heptacis-undecaprenol = 3 UDP + [GalNAc-α-(1→4)]4-GalNAc-α-(1→3)-diNAcBac-PP-tritrans,heptacis-undecaprenol
For diagram of undecaprenyldiphosphoheptasaccharide biosynthesis, click here
Glossary: diNAcBac = N,N′-diacetyl-D-bacillosamine = 2,4-diacetamido-2,4,6-trideoxy-D-glucopyranose
Other name(s): PglH
Systematic name: UDP-N-acetyl-α-D-galactosamine:GalNAc-α-(1→4)-GalNAc-α-(1→3)-diNAcBac-PP-tritrans,heptacis-undecaprenol 4-α-N-acetyl-D-galactosaminyltransferase
Comments: Isolated from Campylobacter jejuni. Part of a bacterial N-linked glycosylation pathway.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc
References:
1.  Glover, K.J., Weerapana, E. and Imperiali, B. In vitro assembly of the undecaprenylpyrophosphate-linked heptasaccharide for prokaryotic N-linked glycosylation. Proc. Natl. Acad. Sci. USA 102 (2005) 14255–14259. [DOI] [PMID: 16186480]
2.  Troutman, J.M. and Imperiali, B. Campylobacter jejuni PglH is a single active site processive polymerase that utilizes product inhibition to limit sequential glycosyl transfer reactions. Biochemistry 48 (2009) 2807–2816. [DOI] [PMID: 19159314]
3.  Borud, B., Viburiene, R., Hartley, M.D., Paulsen, B.S., Egge-Jacobsen, W., Imperiali, B. and Koomey, M. Genetic and molecular analyses reveal an evolutionary trajectory for glycan synthesis in a bacterial protein glycosylation system. Proc. Natl. Acad. Sci. USA 108 (2011) 9643–9648. [DOI] [PMID: 21606362]
[EC 2.4.1.292 created 2012]
 
 
EC 3.2.1.1     Relevance: 92.8%
Accepted name: α-amylase
Reaction: Endohydrolysis of (1→4)-α-D-glucosidic linkages in polysaccharides containing three or more (1→4)-α-linked D-glucose units
Other name(s): glycogenase; α amylase; endoamylase; Taka-amylase A; 1,4-α-D-glucan glucanohydrolase
Systematic name: 4-α-D-glucan glucanohydrolase
Comments: Acts on starch, glycogen and related polysaccharides and oligosaccharides in a random manner; reducing groups are liberated in the α-configuration. The term "α" relates to the initial anomeric configuration of the free sugar group released and not to the configuration of the linkage hydrolysed.
Links to other databases: BRENDA, EXPASY, GTD, KEGG, MetaCyc, PDB, CAS registry number: 9000-90-2
References:
1.  Fischer, E.H. and Stein, E.A. α-Amylases. In: Boyer, P.D., Lardy, H. and Myrbäck, K. (Ed.), The Enzymes, 2nd edn, vol. 4, Academic Press, New York, 1960, pp. 313–343.
2.  Manners, D.J. Enzymic synthesis and degradation of starch and glycogen. Adv. Carbohydr. Chem. 17 (1962) 371–430.
3.  Schwimmer, S. and Balls, A.K. Isolation and properties of crystalline α-amylase from germinated barley. J. Biol. Chem. 179 (1949) 1063–1074. [PMID: 18134570]
[EC 3.2.1.1 created 1961]
 
 
EC 2.4.3.7     Relevance: 92.7%
Accepted name: α-N-acetylneuraminyl-2,3-β-galactosyl-1,3-N-acetylgalactosaminide 6-α-sialyltransferase
Reaction: CMP-N-acetylneuraminate + N-acetyl-α-neuraminyl-(2→3)-β-D-galactosyl-(1→3)-N-acetyl-D-galactosaminyl-R = CMP + N-acetyl-α-neuraminyl-(2→3)-β-D-galactosyl-(1→3)-[N-acetyl-α-neuraminyl-(2→6)]-N-acetyl-D-galactosaminyl-R
For diagram of reaction, click here
Other name(s): sialyltransferase; cytidine monophosphoacetylneuraminate-(α-N-acetylneuraminyl-2,3-β-galactosyl-1,3)-N-acetylgalactosaminide-α-2,6-sialyltransferase; α-N-acetylneuraminyl-2,3-β-galactosyl-1,3-N-acetyl-galactosaminide α-2,6-sialyltransferase; SIAT7; ST6GALNAC; (α-N-acetylneuraminyl-2,3-β-galactosyl-1,3)-N-acetyl-galactosaminide 6-α-sialyltransferase; CMP-N-acetylneuraminate:(α-N-acetylneuraminyl-2,3-β-D-galactosyl-1,3)-N-acetyl-D-galactosaminide α-2,6-N-acetylneuraminyl-transferase
Systematic name: CMP-N-acetylneuraminate:N-acetyl-α-neuraminyl-(2→3)-β-D-galactosyl-(1→3)- N-acetyl-D-galactosaminide galactosamine-6-α-N-acetylneuraminyltransferase
Comments: Attaches N-acetylneuraminic acid in α-2,6-linkage to N-acetylgalactosamine only when present in the structure of α-N-acetylneuraminyl-(2→3)-β-galactosyl-(1→3)-N-acetylgalactosaminyl-R, where R may be protein or p-nitrophenol. Not identical with EC 2.4.3.3 α-N-acetylgalactosaminide α-2,6-sialyltransferase.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number: 129924-24-9
References:
1.  Bergh, M.L.E., Hooghwinkel, G.J.M. and Van den Eijnden, D.H. Biosynthesis of the O-glycosidically linked oligosaccharide chains of fetuin. Indications for an α-N-acetylgalactosaminide α2→6 sialyltransferase with a narrow acceptor specificity in fetal calf liver. J. Biol. Chem. 258 (1983) 7430–7436. [PMID: 6190802]
[EC 2.4.3.7 created 1984 as EC 2.4.99.7, modified 1986, modified 2004, transferred 2022 to EC 2.4.3.7]
 
 
EC 3.2.1.18     Relevance: 92.4%
Accepted name: exo-α-sialidase
Reaction: Hydrolysis of α-(2→3)-, α-(2→6)-, α-(2→8)- glycosidic linkages of terminal sialic acid residues in oligosaccharides, glycoproteins, glycolipids, colominic acid and synthetic substrates
Other name(s): neuraminidase; sialidase; α-neuraminidase; acetylneuraminidase
Systematic name: acetylneuraminyl hydrolase
Comments: The enzyme does not act on 4-O-acetylated sialic acids. endo-α-Sialidase activity is listed as EC 3.2.1.129, endo-α-sialidase. See also EC 4.2.2.15 anhydrosialidase.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 9001-67-6
References:
1.  Schauer, R. Sialic acids. Adv. Carbohydr. Chem. Biochem. 40 (1982) 131–234. [DOI] [PMID: 6762816]
2.  Cabezas, J.A. Some questions and suggestions on the type references of the official nomenclature (IUB) for sialidase(s) and endosialidase. Biochem. J. 278 (1991) 311–312. [PMID: 1883340]
[EC 3.2.1.18 created 1961, modified 1999]
 
 
EC 2.4.1.166     Relevance: 92.3%
Accepted name: raffinose—raffinose α-galactosyltransferase
Reaction: 2 raffinose = 1F-α-D-galactosylraffinose + sucrose
Glossary: raffinose = β-D-fructofuranosyl α-D-galactopyranosyl-(1→6)-α-D-glucopyranoside
Other name(s): raffinose (raffinose donor) galactosyltransferase; raffinose:raffinose α-galactosyltransferase; raffinose—raffinose α-galactotransferase
Systematic name: raffinose:raffinose α-D-galactosyltransferase
Comments: The 3F position of raffinose can also act as galactosyl acceptor; the enzyme is involved in the accumulation of the tetrasaccharides lychnose and isolychnose in the leaves of Cerastium arvense and other plants of the family Caryophyllaceae during late autumn.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number: 93389-38-9
References:
1.  Hopf, H., Gruber, G., Zinn, A. and Kandler, O. Physiology and biosynthesis of lychnose in Cerastium arvense. Planta 162 (1984) 283–288. [PMID: 24253101]
[EC 2.4.1.166 created 1989]
 
 
EC 3.2.1.225     Relevance: 92.2%
Accepted name: D-arabinan exo α-(1,3)/(1,5)-arabinofuranosidase (non-reducing end)
Reaction: Hydrolysis of terminal non-reducing α-D-arabinofuranoside residues in D-arabinans
Other name(s): exo-α-D-arabinofuranosidase; DgGH172a; DgGH172b; DgGH172c; NocGH172; MycGH172; ExoMA1
Systematic name: α-D-arabinofuranoside non-reducing end α-D-arabinofuranosidase (configuration-retaining)
Comments: The enzyme hydrolyses α-D-arabinofuranosides with (1→3)- and (1→5)-linkages in D-arabinan core structure of lipoarabinomannan and arabinogalactan of mycobacterial cell wall. cf. EC 3.2.1.55, non-reducing end α-L-arabinofuranosidase; EC 3.2.1.224, D-arabinan exo β-(1,2)-arabinofuranosidase (non-reducing end); and EC 3.2.1.226, D-arabinan endo α-(1,5)-arabinofuranosidase.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc
References:
1.  Al-Jourani, O., Benedict, S.T., Ross, J., Layton, A.J., van der Peet, P., Marando, V.M., Bailey, N.P., Heunis, T., Manion, J., Mensitieri, F., Franklin, A., Abellon-Ruiz, J., Oram, S.L., Parsons, L., Cartmell, A., Wright, G.SA., Basle, A., Trost, M., Henrissat, B., Munoz-Munoz, J., Hirt, R.P., Kiessling, L.L., Lovering, A.L., Williams, S.J., Lowe, E.C. and Moynihan, P.J. Identification of D-arabinan-degrading enzymes in mycobacteria. Nat. Commun. 14:2233 (2023). [DOI] [PMID: 37076525]
2.  Shimokawa, M., Ishiwata, A., Kashima, T., Nakashima, C., Li, J., Fukushima, R., Sawai, N., Nakamori, M., Tanaka, Y., Kudo, A., Morikami, S., Iwanaga, N., Akai, G., Shimizu, N., Arakawa, T., Yamada, C., Kitahara, K., Tanaka, K., Ito, Y., Fushinobu, S. and Fujita, K. Identification and characterization of endo-α-, exo-α-, and exo-β-D-arabinofuranosidases degrading lipoarabinomannan and arabinogalactan of mycobacteria. Nat. Commun. 14:5803 (2023). [DOI] [PMID: 37726269]
[EC 3.2.1.225 created 2024]
 
 
EC 2.4.1.373     Relevance: 92.1%
Accepted name: α-(1→2) branching sucrase
Reaction: sucrose + a (1→6)-α-D-glucan = D-fructose + a (1→6)-α-D-glucan containing a (1→2)-α-D-glucose branch
Systematic name: sucrose:(1→6)-α-D-glucan 2-α-D-glucosyl-transferase
Comments: The glucansucrases transfer a D-glucosyl residue from sucrose to a glucan chain. They are classified based on the linkage by which they attach the transferred residue. In some cases, in which the enzyme forms more than one linkage type, classification relies on the relative proportion of the linkages that are generated. This enzyme introduces α(1→2) branches into (1→6)-α-D-glucans.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc
References:
1.  Fabre, E., Bozonnet, S., Arcache, A., Willemot, R.M., Vignon, M., Monsan, P. and Remaud-Simeon, M. Role of the two catalytic domains of DSR-E dextransucrase and their involvement in the formation of highly α-1,2 branched dextran. J. Bacteriol. 187 (2005) 296–303. [PMID: 15601714]
2.  Brison, Y., Laguerre, S., Lefoulon, F., Morel, S., Monties, N., Potocki-Veronese, G., Monsan, P. and Remaud-Simeon, M. Branching pattern of gluco-oligosaccharides and 1.5kDa dextran grafted by the α-1,2 branching sucrase GBD-CD2. Carbohydr. Polym. 94 (2013) 567–576. [PMID: 23544576]
3.  Passerini, D., Vuillemin, M., Ufarte, L., Morel, S., Loux, V., Fontagne-Faucher, C., Monsan, P., Remaud-Simeon, M. and Moulis, C. Inventory of the GH70 enzymes encoded by Leuconostoc citreum NRRL B-1299 - identification of three novel α-transglucosylases. FEBS J. 282 (2015) 2115–2130. [PMID: 25756290]
[EC 2.4.1.373 created 2019]
 
 
EC 2.4.99.16     Relevance: 92.1%
Accepted name: starch synthase (maltosyl-transferring)
Reaction: α-maltose 1-phosphate + [(1→4)-α-D-glucosyl]n = phosphate + [(1→4)-α-D-glucosyl]n+2
Other name(s): α1,4-glucan:maltose-1-P maltosyltransferase; GMPMT
Systematic name: α-maltose 1-phosphate:(1→4)-α-D-glucan 4-α-D-maltosyltransferase
Comments: The enzyme from the bacterium Mycobacterium smegmatis is specific for maltose. It has no activity with α-D-glucose.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB
References:
1.  Elbein, A.D., Pastuszak, I., Tackett, A.J., Wilson, T. and Pan, Y.T. Last step in the conversion of trehalose to glycogen: a mycobacterial enzyme that transfers maltose from maltose 1-phosphate to glycogen. J. Biol. Chem. 285 (2010) 9803–9812. [DOI] [PMID: 20118231]
2.  Syson, K., Stevenson, C.E., Rejzek, M., Fairhurst, S.A., Nair, A., Bruton, C.J., Field, R.A., Chater, K.F., Lawson, D.M. and Bornemann, S. Structure of Streptomyces maltosyltransferase GlgE, a homologue of a genetically validated anti-tuberculosis target. J. Biol. Chem. 286 (2011) 38298–38310. [DOI] [PMID: 21914799]
[EC 2.4.99.16 created 2012]
 
 
EC 2.4.1.258     Relevance: 92%
Accepted name: dolichyl-P-Man:Man5GlcNAc2-PP-dolichol α-1,3-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→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-α-D-GlcNAc-diphosphodolichol = α-D-Man-(1→2)-α-D-Man-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→3)-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-α-D-GlcNAc-diphosphodolichol + dolichyl phosphate
For diagram of dolichyltetradecasaccharide biosynthesis, click here
Other name(s): Man5GlcNAc2-PP-Dol mannosyltransferase; ALG3; dolichyl-P-Man:Man(5)GlcNAc(2)-PP-dolichyl mannosyltransferase; Not56-like protein; Alg3 α-1,3-mannosyl transferase; Dol-P-Man:Man5GlcNAc2-PP-Dol α-1,3-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→6)]-D-Man-β-(1→4)-D-GlcNAc-β-(1→4)-D-GlcNAc-diphosphodolichol α-1,3-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→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-α-D-GlcNAc-diphosphodolichol 3-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-dolichol to Man9Glc-NAc2-PP-dolichol on the lumenal side use dolichyl β-D-mannosyl phosphate. The first step of this assembly pathway on the luminal side of the endoplasmic reticulum is catalysed by ALG3.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc
References:
1.  Sharma, C.B., Knauer, R. and Lehle, L. Biosynthesis of lipid-linked oligosaccharides in yeast: the ALG3 gene encodes the Dol-P-Man:Man5GlcNAc2-PP-Dol mannosyltransferase. Biol. Chem. 382 (2001) 321–328. [DOI] [PMID: 11308030]
2.  Cipollo, J.F. and Trimble, R.B. The accumulation of Man(6)GlcNAc(2)-PP-dolichol in the Saccharomyces cerevisiae Δalg9 mutant reveals a regulatory role for the Alg3p α1,3-Man middle-arm addition in downstream oligosaccharide-lipid and glycoprotein glycan processing. J. Biol. Chem. 275 (2000) 4267–4277. [DOI] [PMID: 10660594]
[EC 2.4.1.258 created 1976 as EC 2.4.1.130, part transferred 2011 to EC 2.4.1.258, modified 2012]
 
 
EC 3.2.1.221     Relevance: 92%
Accepted name: MMP endo-(1,4)-3-O-methyl-α-D-mannosidase
Reaction: Endohydrolysis of 3-O-methyl-α-D-mannosyl-(1→4)-3-O-methyl-D-mannose linkages within (1,4)-3-O-methyl-α-D-mannnan substrates
Glossary: MMP = 3-O-methylmannose polysaccharide = α-D-mannosyl-(1→4)-[3-O-methyl-α-D-mannosyl-(1→4)]n-1-O,3-O-dimethyl-α-D-mannose
Other name(s): MMP α-(1→4)-endomannosidase; mmpH (gene name)
Systematic name: (1,4)-3-O-methyl-α-D-mannan 4-α-3-O-methyl-D-mannohydrolase
Comments: The enzyme, present in mycobacterial species that produce 3-O-methylmannose polysaccharide (MMP), is involved in recycling and biosynthesis of the polymer. The enzyme has been shown to cleave substrates in the range of 11–14 mannose residues.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc
References:
1.  Maranha, A., Costa, M., Ripoll-Rozada, J., Manso, J.A., Miranda, V., Mendes, V.M., Manadas, B., Macedo-Ribeiro, S., Ventura, M.R., Pereira, P.JB. and Empadinhas, N. Self-recycling and partially conservative replication of mycobacterial methylmannose polysaccharides. Commun Biol 6:108 (2023). [DOI] [PMID: 36707645]
[EC 3.2.1.221 created 2023]
 
 
EC 2.4.1.232     Relevance: 91.4%
Accepted name: initiation-specific α-1,6-mannosyltransferase
Reaction: Transfers an α-D-mannosyl residue from GDP-mannose into lipid-linked oligosaccharide, forming an α-(1→6)-D-mannosyl-D-mannose linkage
Other name(s): α-1,6-mannosyltransferase; GDP-mannose:oligosaccharide 1,6-α-D-mannosyltransferase; GDP-mannose:glycolipid 1,6-α-D-mannosyltransferase; glycolipid 6-α-mannosyltransferase; GDP-mannose:oligosaccharide 1,6-α-D-mannosyltransferase
Systematic name: GDP-mannose:oligosaccharide 6-α-D-mannosyltransferase
Comments: Requires Mn2+. In Saccharomyces cerevisiae, this enzyme catalyses an essential step in the outer chain elongation of N-linked oligosaccharides. Man8GlcNAc and Man9GlcNAc are equally good substrates.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number: 346003-17-6
References:
1.  Romero, P.A. and Herscovics, A. Glycoprotein biosynthesis in Saccharomyces cerevisiae. Characterization of α-1,6-mannosyltransferase which initiates outer chain formation. J. Biol. Chem. 264 (1989) 1946–1950. [PMID: 2644248]
2.  Reason, A.J., Dell, A., Romero, P.A. and Herscovics, A. Specificity of the mannosyltransferase which initiates outer chain formation in Saccharomyces cerevisiae. Glycobiology 1 (1991) 387–391. [DOI] [PMID: 1820199]
3.  Nakanishi-Shindo, Y., Nakayama, K., Tanaka, A., Toda, Y. and Jigami, Y. Structure of the N-linked oligosaccharides that show the complete loss of α-1,6-polymannose outer chain from och1, och1 mnn1, and och1 mnn1 alg3 mutants of Saccharomyces cerevisiae. J. Biol. Chem. 268 (1993) 26338–26345. [PMID: 8253757]
4.  Yamamoto, K., Okamoto, M., Yoko-o, T. and Jigami, Y. Salt stress induces the expression of the Schizosaccharomyces pombe och1+, which encodes an initiation-specific α-1,6-mannosyltransferase for N-linked outer chain synthesis of cell wall mannoproteins. Biosci. Biotechnol. Biochem. 67 (2003) 927–929. [DOI] [PMID: 12784644]
5.  Cui, Z., Horecka, J. and Jigami, Y. Cdc4 is involved in the transcriptional control of OCH1, a gene encoding α-1,6-mannosyltransferase in Saccharomyces cerevisiae. Yeast 19 (2002) 69–77. [DOI] [PMID: 11754484]
6.  Tsukahara, K., Watanabe, T., Yoko-o, T. and Chigami, Y. Schizosaccharomyces pombe och1+ gene encoding α-1,6-mannosyltransferase and use of och1+ gene knockout fission yeast for production of glycoproteins with reduced glycosylation. Jpn. Kokai Tokkyo Koho Koho (2001) 11.
7.  Nakayama, K., Nakanishi-Shindo, Y., Tanaka, A., Haga-Toda, Y. and Jigami, Y. Substrate specificity of α-1,6-mannosyltransferase that initiates N-linked mannose outer chain elongation in Saccharomyces cerevisiae. FEBS Lett. 412 (1997) 547–550. [DOI] [PMID: 9276464]
8.  Suzuki, A., Shibata, N., Suzuki, M., Saitoh, F., Takata, Y., Oshie, A., Oyamada, H., Kobayashi, H., Suzuki, S. and Okawa, Y. Characterization of α-1,6-mannosyltransferase responsible for the synthesis of branched side chains in Candida albicans mannan. Eur. J. Biochem. 240 (1996) 37–44. [DOI] [PMID: 8797833]
9.  Yip, C.L., Welch, S.K., Klebl, F., Gilbert, T., Seidel, P., Grant, F., O'Hara, P.J. and MacKay, V.L. Cloning and analysis of the Saccharomyces cerevisiae MNN9 and MNN1 genes required for complex glycosylation of secreted proteins. Proc. Natl. Acad. Sci. USA 91 (1994) 2723–2727. [DOI] [PMID: 8146181]
[EC 2.4.1.232 created 2004]
 
 
EC 2.4.1.199     Relevance: 91.4%
Accepted name: β-mannosylphosphodecaprenol—mannooligosaccharide 6-mannosyltransferase
Reaction: β-D-mannosylphosphodecaprenol + (1→6)-α-D-mannosyloligosaccharide = decaprenol phosphate + (1→6)-α-D-mannosyl-(1→6)-α-D-mannosyl-oligosaccharide
Other name(s): mannosylphospholipid-methylmannoside α-1,6-mannosyltransferase; β-D-mannosylphosphodecaprenol:1,6-α-D-mannosyloligosaccharide 1,6-α-D-mannosyltransferase
Systematic name: β-D-mannosylphosphodecaprenol:(1→6)-α-D-mannosyloligosaccharide 6-α-D-mannosyltransferase
Comments: Involved in the formation of mannooligosaccharides in the membrane of Mycobacterium smegmatis.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number: 125008-27-7
References:
1.  Yokoyama, K. and Ballou, C.E. Synthesis of α1→6-mannooligosaccharides in Mycobacterium smegmatis. Function of β-mannosylphosphoryldecaprenol as the mannosyl donor. J. Biol. Chem. 264 (1989) 21621–21628. [PMID: 2480954]
[EC 2.4.1.199 created 1992]
 
 
EC 5.4.99.65     Relevance: 91.3%
Accepted name: pre-α-onocerin synthase
Reaction: (3S,22S)-2,3:22,23-diepoxy-2,3,22,23-tetrahydrosqualene = pre-α-onocerin
For diagram of α-onocerin biosynthesis, click here
Glossary: pre-α-onocerin = (21S)-21,22-epoxypolypoda-8(26)-13,17-trien-3β-ol
Other name(s): LCC
Systematic name: (3S,22S)-2,3:22,23-diepoxy-2,3,22,23-tetrahydrosqualene mutase (cyclizing, pre-α-onocerin-forming)
Comments: Isolated from the plant Lycopodium clavatum. The enzyme does not act on (3S)-2,3-epoxy-2,3-dihydrosqualene and does not form any α-onocerin.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc
References:
1.  Araki, T., Saga, Y., Marugami, M., Otaka, J., Araya, H., Saito, K., Yamazaki, M., Suzuki, H. and Kushiro, T. Onocerin biosynthesis requires two highly dedicated triterpene cyclases in a fern Lycopodium clavatum. ChemBioChem 17 (2016) 288–290. [DOI] [PMID: 26663356]
[EC 5.4.99.65 created 2017]
 
 
EC 2.4.99.7      
Transferred entry: α-N-acetylneuraminyl-2,3-β-galactosyl-1,3-N-acetylgalactosaminide 6-α-sialyltransferase. Now EC 2.4.3.7, α-N-acetylneuraminyl-2,3-β-galactosyl-1,3-N-acetylgalactosaminide 6-α-sialyltransferase
[EC 2.4.99.7 created 1984, modified 1986, modified 2004, deleted 2022]
 
 
EC 2.4.1.377     Relevance: 91%
Accepted name: dTDP-Rha:α-D-Gal-diphosphoundecaprenol α-1,3-rhamnosyltransferase
Reaction: dTDP-β-L-rhamnose + α-D-galactosyl-diphospho-ditrans,octacis-undecaprenol = dTDP + α-L-Rha-(1→3)-α-D-Gal-PP-Und
Glossary: α-L-Rha-(1→3)-α-D-Gal-PP-Und = α-L-rhamnopyranosyl-(1→3)-α-D-galactopyranosyl-diphospho-ditrans,octacis-undecaprenol
Other name(s): wbaN (gene name); rfbN (gene name)
Systematic name: dTDP-β-L-rhamnose:α-D-galactosyl-diphospho-ditrans,octacis-undecaprenol 3-α-rhamnosyltransferase (configuration-inverting)
Comments: The enzyme, characterized from several Salmonella strains, participates in the biosynthesis of the repeat unit of O antigens produced by strains that belong to the A, B, D and E groups.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc
References:
1.  Liu, D., Haase, A.M., Lindqvist, L., Lindberg, A.A. and Reeves, P.R. Glycosyl transferases of O-antigen biosynthesis in Salmonella enterica: identification and characterization of transferase genes of groups B, C2, and E1. J. Bacteriol. 175 (1993) 3408–3413. [DOI] [PMID: 7684736]
[EC 2.4.1.377 created 2021]
 
 
EC 2.4.1.346     Relevance: 90.7%
Accepted name: phosphatidyl-myo-inositol dimannoside synthase
Reaction: (1) GDP-α-D-mannose + 2-O-α-D-mannosyl-1-phosphatidyl-1D-myo-inositol = GDP + 2,6-di-O-α-D-mannosyl-1-phosphatidyl-1D-myo-inositol
(2) GDP-α-D-mannose + 2-O-(6-O-acyl-α-D-mannosyl)-1-phosphatidyl-1D-myo-inositol = GDP + 2-O-(6-O-acyl-α-D-mannosyl)-6-O-α-D-mannosyl-1-phosphatidyl-1D-myo-inositol
Glossary: 1-phosphatidyl-1D-myo-inositol = PtdIns
Other name(s): mannosyltransferase PimB; PimB; guanosine diphosphomannose-phosphatidyl-inositol α-mannosyltransferase (ambiguous)
Systematic name: GDP-α-D-mannose:2-O-α-D-mannosyl-1-phosphatidyl-1D-myo-inositol 6-α-D-mannosyltransferase (configuration-retaining)
Comments: Requires Mg2+. The enzyme, found in Corynebacteriales, is involved in the biosynthesis of phosphatidyl-myo-inositol mannosides (PIMs).
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB
References:
1.  Guerin, M.E., Kaur, D., Somashekar, B.S., Gibbs, S., Gest, P., Chatterjee, D., Brennan, P.J. and Jackson, M. New insights into the early steps of phosphatidylinositol mannoside biosynthesis in mycobacteria: PimB′ is an essential enzyme of Mycobacterium smegmatis. J. Biol. Chem. 284 (2009) 25687–25696. [DOI] [PMID: 19638342]
2.  Mishra, A.K., Batt, S., Krumbach, K., Eggeling, L. and Besra, G.S. Characterization of the Corynebacterium glutamicum Δ pimB′ Δ mgtA double deletion mutant and the role of Mycobacterium tuberculosis orthologues Rv2188c and Rv0557 in glycolipid biosynthesis. J. Bacteriol. 191 (2009) 4465–4472. [DOI] [PMID: 19395496]
3.  Batt, S.M., Jabeen, T., Mishra, A.K., Veerapen, N., Krumbach, K., Eggeling, L., Besra, G.S. and Futterer, K. Acceptor substrate discrimination in phosphatidyl-myo-inositol mannoside synthesis: structural and mutational analysis of mannosyltransferase Corynebacterium glutamicum PimB′. J. Biol. Chem. 285 (2010) 37741–37752. [DOI] [PMID: 20843801]
[EC 2.4.1.346 created 2017]
 
 
EC 2.4.1.349     Relevance: 90.6%
Accepted name: mannosyl-N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol 3-α-mannosyltransferase
Reaction: 2 GDP-α-D-mannose + α-D-mannosyl-(1→3)-N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol = 2 GDP + α-D-mannosyl-(1→3)-α-D-mannosyl-(1→3)-α-D-mannosyl-(1→3)-N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol
Other name(s): WbdB
Systematic name: GDP-α-D-mannose:α-D-mannosyl-(1→3)-N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol 3-α-mannosyltransferase (configuration-retaining)
Comments: The enzyme is involved in the biosynthesis of the linker region of the polymannose O-polysaccharide in the outer leaflet of the membrane of Escherichia coli serotypes O8, O9 and O9a. It has no activity with N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol (cf. EC 2.4.1.348, N-acetyl-α-D-glucosaminyl-diphospho-ditrans,octacis-undecaprenol 3-α-mannosyltransferase).
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc
References:
1.  Greenfield, L.K., Richards, M.R., Li, J., Wakarchuk, W.W., Lowary, T.L. and Whitfield, C. Biosynthesis of the polymannose lipopolysaccharide O-antigens from Escherichia coli serotypes O8 and O9a requires a unique combination of single- and multiple-active site mannosyltransferases. J. Biol. Chem. 287 (2012) 35078–35091. [DOI] [PMID: 22875852]
[EC 2.4.1.349 created 2017]
 
 


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