EC 3.2.1.1     
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.
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 3.2.1.2     
Accepted name: β-amylase
Reaction: Hydrolysis of (1→4)-α-D-glucosidic linkages in polysaccharides so as to remove successive maltose units from the non-reducing ends of the chains
Other name(s): saccharogen amylase; glycogenase; β amylase; 1,4-α-D-glucan maltohydrolase
Systematic name: 4-α-D-glucan maltohydrolase
Comments: Acts on starch, glycogen and related polysaccharides and oligosaccharides producing β-maltose by an inversion. The term ‘β’' relates to the initial anomeric configuration of the free sugar group released and not to the configuration of the linkage hydrolysed.
References:
1.  Balls, A.K., Walden, M.K. and Thompson, R.R. A crystalline β-amylase from sweet potatoes. J. Biol. Chem. 173 (1948) 9–19. [PMID: 18902365]
2.  French, D. β-Amylases. In: Boyer, P.D., Lardy, H. and Myrbäck, K. (Ed.), The Enzymes, 2nd edn, vol. 4, Academic Press, New York, 1960, pp. 345–368.
3.  Manners, D.J. Enzymic synthesis and degradation of starch and glycogen. Adv. Carbohydr. Chem. 17 (1962) 371–430.
[EC 3.2.1.2 created 1961]
 
 
EC 3.2.1.3     
Accepted name: glucan 1,4-α-glucosidase
Reaction: Hydrolysis of terminal (1→4)-linked α-D-glucose residues successively from non-reducing ends of the chains with release of β-D-glucose
Other name(s): glucoamylase; amyloglucosidase; γ-amylase; lysosomal α-glucosidase; acid maltase; exo-1,4-α-glucosidase; glucose amylase; γ-1,4-glucan glucohydrolase; acid maltase; 1,4-α-D-glucan glucohydrolase
Systematic name: 4-α-D-glucan glucohydrolase
Comments: Most forms of the enzyme can rapidly hydrolyse 1,6-α-D-glucosidic bonds when the next bond in the sequence is 1,4, and some preparations of this enzyme hydrolyse 1,6- and 1,3-α-D-glucosidic bonds in other polysaccharides. This entry covers all such enzymes acting on polysaccharides more rapidly than on oligosaccharides. EC 3.2.1.20 α-glucosidase, from mammalian intestine, can catalyse similar reactions.
References:
1.  French, D. and Knapp, D.W. The maltase of Clostridium acetobutylicum. J. Biol. Chem. 187 (1950) 463–471. [PMID: 14803428]
2.  Illingworth Brown, B. and Brown, D.H. The subcellular distribution of enzymes in type II glycogenosis and the occurrence of an oligo-α-1,4-glucan glucohydrolase in human tissues. Biochim. Biophys. Acta 110 (1965) 124–133. [PMID: 4286143]
3.  Jeffrey, P.L., Brown, D.H. and Brown, B.I. Studies of lysosomal α-glucosidase. I. Purification and properties of the rat liver enzyme. Biochemistry 9 (1970) 1403–1415. [PMID: 4313883]
4.  Kelly, J.J. and Alpers, D.H. Properties of human intestinal glucoamylase. Biochim. Biophys. Acta 315 (1973) 113–122. [PMID: 4743896]
5.  Miller, K.D. and Copeland, W.H. A blood trans-α-glucosylase. Biochim. Biophys. Acta 22 (1956) 193–194. [PMID: 13373867]
6.  Tsujisaka, Y., Fukimoto, J. and Yamamoto, T. Specificity of crystalline saccharogenic amylase of moulds. Nature 181 (1958) 770–771. [PMID: 13517301]
[EC 3.2.1.3 created 1961]
 
 
EC 3.2.1.4     
Accepted name: cellulase
Reaction: Endohydrolysis of (1→4)-β-D-glucosidic linkages in cellulose, lichenin and cereal β-D-glucans
Other name(s): endo-1,4-β-D-glucanase; β-1,4-glucanase; β-1,4-endoglucan hydrolase; celluase A; cellulosin AP; endoglucanase D; alkali cellulase; cellulase A 3; celludextrinase; 9.5 cellulase; avicelase; pancellase SS; 1,4-(1,3;1,4)-β-D-glucan 4-glucanohydrolase
Systematic name: 4-β-D-glucan 4-glucanohydrolase
Comments: Will also hydrolyse 1,4-linkages in β-D-glucans also containing 1,3-linkages.
References:
1.  Datta, P.K., Hanson, K.R. and Whitaker, D.R. Improved procedures for preparation and characterization of Myrothecum cellulase. III. Molecular weight, amino acid composition, terminal residues, and other properties. Can. J. Biochem. Physiol. 41 (1963) 697–705. [PMID: 14025219]
2.  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.
3.  Myers, F.L. and Northcote, D.H. Partial purification and some properties of a cellulase from Helix pomatia. Biochem. J. 71 (1959) 749–756. [PMID: 13651124]
4.  Nishizawa, K. and Hashimoto, Y. Cellulose splitting enzymes. VI. Difference in the specificities of cellulase and β-glucosidase from Irpex lacteus. Arch. Biochem. Biophys. 81 (1959) 211–222. [PMID: 13637982]
5.  Whitaker, D.R., Hanson, K.R. and Datta, P.K. Improved procedures for preparation and characterization of myrothecium cellulase. 2. Purification procedures. Can. J. Biochem. Physiol. 41 (1963) 671–696. [PMID: 14000266]
6.  Hatfield, R. and Nevins, D.J. Purification and properties of an endoglucanase isolated from the cell walls of Zea mays seedlings. Carbohydr. Res. 148 (1986) 265–278.
7.  Hatfield, R. and Nevins, D.J. Hydrolytic activity and substrate specificity of an endoglucanase from Zea mays seedling cell walls. Plant Physiol. 83 (1987) 203–207. [PMID: 16665203]
8.  Inohue, M., Hayashgi, K. and Nevins, D.J. Polypeptide characteristics and immunological properties of exo- and endoglucanases purified from maize coleoptile cell walls. J. Plant Physiol. 154 (1999) 334–340.
[EC 3.2.1.4 created 1961, modified 2001]
 
 
EC 3.2.1.5      
Deleted entry:  licheninase
[EC 3.2.1.5 created 1961, deleted 1964]
 
 
EC 3.2.1.6     
Accepted name: endo-1,3(4)-β-glucanase
Reaction: Endohydrolysis of (1→3)- or (1→4)-linkages in β-D-glucans when the glucose residue whose reducing group is involved in the linkage to be hydrolysed is itself substituted at C-3
Other name(s): endo-1,3-β-D-glucanase; laminarinase; laminaranase; β-1,3-glucanase; β-1,3-1,4-glucanase; endo-1,3-β-glucanase; endo-β-1,3(4)-glucanase; endo-β-1,3-1,4-glucanase; endo-β-(1→3)-D-glucanase; endo-1,3-1,4-β-D-glucanase; endo-β-(1-3)-D-glucanase; endo-β-1,3-glucanase IV; endo-1,3-β-D-glucanase; 1,3-(1,3;1,4)-β-D-glucan 3(4)-glucanohydrolase
Systematic name: 3(or 4)-β-D-glucan 3(4)-glucanohydrolase
Comments: Substrates include laminarin, lichenin and cereal D-glucans; different from EC 3.2.1.52 β-N-acetylhexosaminidase.
References:
1.  Barras, D.R. and Stone, B.A. β-1,3-Glucan hydrolases from Euglena gracilis. I. The nature of the hydrolases. Biochim. Biophys. Acta 191 (1969) 329–341. [PMID: 5354264]
2.  Barras, D.R. and Stone, B.A. β-1,3-Glucan hydrolases from Euglena gracilis. II. Purification and properties of the β-1,3-glucan exo-hydrolase. Biochim. Biophys. Acta 191 (1969) 342–353. [PMID: 5354265]
3.  Cunningham, L.W. and Manners, D.J. Enzymic degradation of lichenin. Biochem. J. 80 (1961) 42.
4.  Reese, E.T. and Mandels, M. β-D-1,3-Glucanases in fungi. Can. J. Microbiol. 5 (1959) 173–185. [PMID: 13638895]
5.  Sova, V.V., Elyakova, L.A. and Vaskovsky, V.E. Purification and some properties of β-1,3-glucan glucanohydrolase from the crystalline style of bivalvia, Spisula sachalinensis. Biochim. Biophys. Acta 212 (1970) 111–115. [PMID: 5500926]
[EC 3.2.1.6 created 1961, modified 1976]
 
 
EC 3.2.1.7     
Accepted name: inulinase
Reaction: Endohydrolysis of (2→1)-β-D-fructosidic linkages in inulin
Other name(s): inulase; indoinulinase; endo-inulinase; exoinulinase; 2,1-β-D-fructan fructanohydrolase
Systematic name: 1-β-D-fructan fructanohydrolase
References:
1.  Adams, M., Richtmyer, N.K. and Hudson, C.S. Some enzymes present in highly purified invertase preparations; a contribution to the study of fructofuranosidases, galactosidases, glucosidases and mannosidases. J. Am. Chem. Soc. 65 (1943) 1369–1380.
[EC 3.2.1.7 created 1961]
 
 
EC 3.2.1.8     
Accepted name: endo-1,4-β-xylanase
Reaction: Endohydrolysis of (1→4)-β-D-xylosidic linkages in xylans
Other name(s): endo-(1→4)-β-xylan 4-xylanohydrolase; endo-1,4-xylanase; xylanase; β-1,4-xylanase; endo-1,4-xylanase; endo-β-1,4-xylanase; endo-1,4-β-D-xylanase; 1,4-β-xylan xylanohydrolase; β-xylanase; β-1,4-xylan xylanohydrolase; endo-1,4-β-xylanase; β-D-xylanase
Systematic name: 4-β-D-xylan xylanohydrolase
References:
1.  Howard, B.H., Jones, G. and Purdom, M.R. The pentosanases of some rumen bacteria. Biochem. J. 74 (1960) 173–180. [PMID: 14403433]
2.  Whistler, R.L. and Masek, E. Enzymatic hydolysis of xylan. J. Am. Chem. Soc. 77 (1955) 1241–1243.
[EC 3.2.1.8 created 1961]
 
 
EC 3.2.1.9      
Deleted entry:  amylopectin-1,6-glucosidase
[EC 3.2.1.9 created 1961, deleted 1972]
 
 
EC 3.2.1.10     
Accepted name: oligo-1,6-glucosidase
Reaction: Hydrolysis of (1→6)-α-D-glucosidic linkages in some oligosaccharides produced from starch and glycogen by EC 3.2.1.1 (α-amylase), and in isomaltose
Other name(s): limit dextrinase (erroneous); isomaltase; sucrase-isomaltase; exo-oligo-1,6-glucosidase; dextrin 6α-glucanohydrolase; α-limit dextrinase; dextrin 6-glucanohydrolase; oligosaccharide α-1,6-glucohydrolase; α-methylglucosidase
Systematic name: oligosaccharide 6-α-glucohydrolase
Comments: This enzyme, like EC 3.2.1.33 (amylo-α-1,6-glucosidase), can release an α-1→6-linked glucose, whereas the shortest chain that can be released by EC 3.2.1.41 (pullulanase), EC 3.2.1.142 (limit dextrinase), and EC 3.2.1.68 (isoamylase) is maltose. It also hydrolyses isomaltulose (palatinose), isomaltotriose and panose, but has no action on glycogen or phosphorylase limit dextrin. The enzyme from intestinal mucosa is a single polypeptide chain that also catalyses the reaction of EC 3.2.1.48 (sucrose α-glucosidase). Differs from EC 3.2.1.33 (amylo-α-1,6-glucosidase) in its preference for short-chain substrates and in its not requiring the 6-glucosylated residue to be at a branch point, i.e. linked at both C-1 and C-4.
References:
1.  Hauri, H.-P., Quaroni, A. and Isselbacher, K.J. Biogenesis of intestinal plasma membrane: posttranslational route and cleavage of sucrase-isomaltase. Proc. Natl. Acad. Sci. USA 76 (1979) 5183–5186. [PMID: 291933]
2.  Sjöström, H., Norén, O., Christiansen, L., Wacker, H. and Semenza, G. A fully active, two-active-site, single-chain sucrase-isomaltase from pig small intestine. Implications for the biosynthesis of a mammalian integral stalked membrane protein. J. Biol. Chem. 255 (1980) 11332–11338. [PMID: 7002920]
3.  Rodriguez, I.R., Taravel, F.R. and Whelan, W.J. Characterization and function of pig intestinal sucrase-isomaltase and its separate subunits. Eur. J. Biochem. 143 (1984) 575–582. [PMID: 6479163]
4.  Khan, N.A. and Eaton, N.R. Purification and characterization of maltase and α-methyl glucosidase from yeast. Biochim. Biophys. Acta 146 (1967) 173–180. [PMID: 6060462]
5.  Yamamoto, K., Nakayama, A., Yamamoto, Y. and Tabata, S. Val216 decides the substrate specificity of α-glucosidase in Saccharomyces cerevisiae. Eur. J. Biochem. 271 (2004) 3414–3420. [PMID: 15291818]
[EC 3.2.1.10 created 1961, modified 2000, modified 2013]
 
 
EC 3.2.1.11     
Accepted name: dextranase
Reaction: Endohydrolysis of (1→6)-α-D-glucosidic linkages in dextran
Other name(s): dextran hydrolase; endodextranase; dextranase DL 2; DL 2; endo-dextranase; α-D-1,6-glucan-6-glucanohydrolase; 1,6-α-D-glucan 6-glucanohydrolase
Systematic name: 6-α-D-glucan 6-glucanohydrolase
References:
1.  Bailey, R.W. and Clarke, R.T.J. A bacterial dextranase. Biochem. J. 72 (1959) 49–54. [PMID: 13651134]
2.  Deuel, H. and Stutz, E. Pectic substances and pectic enzymes. Adv. Enzymol. Relat. Areas Mol. Biol. 20 (1958) 341–382. [PMID: 13605988]
3.  Fischer, E.H. and Stein, E.A. Cleavage of O- and S-glycosidic bonds (survey). In: Boyer, P.D., Lardy, H. and Myrbäck, K. (Ed.), The Enzymes, 2nd edn, vol. 4, Academic Press, New York, 1960, pp. 301–312.
4.  Rozenfel'd, E.L. and Lukomskaya, I.S. [The hydrolysis of 1:6 bonds of dextran by animal tissues.] Biokhimiya 21 (1956) 412–415. [PMID: 13363992] (in Russian)
[EC 3.2.1.11 created 1961]
 
 
EC 3.2.1.12      
Deleted entry:  cycloheptaglucanase. Now included with EC 3.2.1.54 cyclomaltodextrinase
[EC 3.2.1.12 created 1961, deleted 1976]
 
 
EC 3.2.1.13      
Deleted entry:  cyclohexaglucanase. Now included with EC 3.2.1.54 cyclomaltodextrinase
[EC 3.2.1.13 created 1961, deleted 1976]
 
 
EC 3.2.1.14     
Accepted name: chitinase
Reaction: Random endo-hydrolysis of N-acetyl-β-D-glucosaminide (1→4)-β-linkages in chitin and chitodextrins
Glossary: chitin = [(1→4)-β-D-GlcpNAc]n = (1→4)-2-acetamido-2-deoxy-β-D-glucan
Other name(s): ChiC; chitodextrinase (ambiguous); 1,4-β-poly-N-acetylglucosaminidase; poly-β-glucosaminidase; β-1,4-poly-N-acetyl glucosamidinase; poly[1,4-(N-acetyl-β-D-glucosaminide)] glycanohydrolase
Systematic name: (1→4)-2-acetamido-2-deoxy-β-D-glucan glycanohydrolase
Comments: The enzyme binds to chitin and randomly cleaves glycosidic linkages in chitin and chitodextrins in a non-processive mode, generating chitooligosaccharides and free ends on which exo-chitinases and exo-chitodextrinases can act. Activity is greatly stimulated in the presence of EC 1.14.99.53, lytic chitin monoxygenase, which attacks the crystalline structure of chitin and makes the polymer more accesible to the chitinase. cf. EC 3.2.1.202, endo-chitodextrinase.
References:
1.  Zechmeister, L. and Tóth, G. Chromatographic adsorption of the enzymes of emulsin which act on chitins. Enzymologia 7 (1939) 165–169.
2.  Tracey, M.V. Chitinase in some basidiomycetes. Biochem. J. 61 (1955) 579–586. [PMID: 13276340]
3.  Fischer, E.H. and Stein, E.A. Cleavage of O- and S-glycosidic bonds (survey). In: Boyer, P.D., Lardy, H. and Myrbäck, K. (Ed.), The Enzymes, 2nd edn, vol. 4, Academic Press, New York, 1960, pp. 301–312.
4.  Connell, T.D., Metzger, D.J., Lynch, J. and Folster, J.P. Endochitinase is transported to the extracellular milieu by the eps-encoded general secretory pathway of Vibrio cholerae. J. Bacteriol. 180 (1998) 5591–5600. [PMID: 9791107]
5.  Francetic, O., Badaut, C., Rimsky, S. and Pugsley, A.P. The ChiA (YheB) protein of Escherichia coli K-12 is an endochitinase whose gene is negatively controlled by the nucleoid-structuring protein H-NS. Mol. Microbiol. 35 (2000) 1506–1517. [PMID: 10760150]
6.  Zverlov, V.V., Fuchs, K.P. and Schwarz, W.H. Chi18A, the endochitinase in the cellulosome of the thermophilic, cellulolytic bacterium Clostridium thermocellum. Appl. Environ. Microbiol. 68 (2002) 3176–3179. [PMID: 12039789]
7.  Rottloff, S., Stieber, R., Maischak, H., Turini, F.G., Heubl, G. and Mithofer, A. Functional characterization of a class III acid endochitinase from the traps of the carnivorous pitcher plant genus, Nepenthes. J. Exp. Bot. 62 (2011) 4639–4647. [PMID: 21633084]
[EC 3.2.1.14 created 1961, modified 2017]
 
 
EC 3.2.1.15     
Accepted name: endo-polygalacturonase
Reaction: (1,4-α-D-galacturonosyl)n+m + H2O = (1,4-α-D-galacturonosyl)n + (1,4-α-D-galacturonosyl)m
Other name(s): pectin depolymerase (ambiguous); pectinase (ambiguous); endopolygalacturonase; pectolase (ambiguous); pectin hydrolase (ambiguous); pectin polygalacturonase (ambiguous); polygalacturonase (ambiguous); poly-α-1,4-galacturonide glycanohydrolase (ambiguous); endogalacturonase; endo-D-galacturonase; poly(1,4-α-D-galacturonide) glycanohydrolase (ambiguous)
Systematic name: (1→4)-α-D-galacturonan glycanohydrolase (endo-cleaving)
Comments: The enzyme catalyses the random hydrolysis of (1→4)-α-D-galactosiduronic linkages in pectate and other galacturonans. Different forms of the enzyme have different tolerances to methyl esterification of the substrate.
References:
1.  Lineweaver, H. and Jansen, E.F. Pectic enzymes. Adv. Enzymol. Relat. Subj. Biochem. 11 (1951) 267–295.
2.  McCready, R.M. and Seegmiller, C.G. Action of pectic enzymes on oligogalacturonic acids and some of their derivatives. Arch. Biochem. Biophys. 50 (1954) 440–450. [PMID: 13159344]
3.  Phaff, H.J. and Demain, A.L. The unienzymatic nature of yeast polygalacturonase. J. Biol. Chem. 218 (1956) 875–884. [PMID: 13295238]
4.  Deuel, H. and Stutz, E. Pectic substances and pectic enzymes. Adv. Enzymol. Relat. Areas Mol. Biol. 20 (1958) 341–382. [PMID: 13605988]
5.  Mill, P.J. and Tuttobello, R. The pectic enzymes of Aspergillus niger. 2. Endopolygalacturonase. Biochem. J. 79 (1961) 57–64. [PMID: 13770689]
[EC 3.2.1.15 created 1961, modified 2019]
 
 
EC 3.2.1.16      
Deleted entry:  alginase
[EC 3.2.1.16 created 1961, deleted 1972]
 
 
EC 3.2.1.17     
Accepted name: lysozyme
Reaction: Hydrolysis of (1→4)-β-linkages between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in a peptidoglycan and between N-acetyl-D-glucosamine residues in chitodextrins
Other name(s): muramidase; globulin G; mucopeptide glucohydrolase; globulin G1; N,O-diacetylmuramidase; lysozyme g; L-7001; 1,4-N-acetylmuramidase; mucopeptide N-acetylmuramoylhydrolase; PR1-lysozyme
Systematic name: peptidoglycan N-acetylmuramoylhydrolase
Comments: cf. also EC 3.2.1.14 chitinase.
References:
1.  Blade, C.C.F., Johnson, L.N., Mair, G.A., North, A.C.T., Phillips, D.C. and Sarma, V.R. Crystallographic studies of the activity of hen egg-white lysozyme. Proc. R. Soc. Lond. B: Biol. Sci. 167 (1967) 378–388. [PMID: 4382801]
2.  Blake, C.C.F., Mair, G.A., North, A.C.T., Phillips, D.C. and Sarma, V.R. On the conformation of the hen egg-white lysozyme molecule. Proc. R. Soc. Lond. B: Biol. Sci. 167 (1967) 365–377. [PMID: 4382800]
3.  Jollès, P. Lysozyme. In: Boyer, P.D., Lardy, H. and Myrbäck, K. (Ed.), The Enzymes, 2nd edn, vol. 4, Academic Press, New York, 1960, pp. 431–445.
[EC 3.2.1.17 created 1961]
 
 
EC 3.2.1.18     
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.
References:
1.  Schauer, R. Sialic acids. Adv. Carbohydr. Chem. Biochem. 40 (1982) 131–234. [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 3.2.1.19      
Deleted entry:  heparinase
[EC 3.2.1.19 created 1961, deleted 1978]
 
 
EC 3.2.1.20     
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.
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. [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. [PMID: 6814909]
[EC 3.2.1.20 created 1961]
 
 
EC 3.2.1.21     
Accepted name: β-glucosidase
Reaction: Hydrolysis of terminal, non-reducing β-D-glucosyl residues with release of β-D-glucose
Other name(s): gentiobiase; cellobiase; emulsin; elaterase; aryl-β-glucosidase; β-D-glucosidase; β-glucoside glucohydrolase; arbutinase; amygdalinase; p-nitrophenyl β-glucosidase; primeverosidase; amygdalase; linamarase; salicilinase; β-1,6-glucosidase
Systematic name: β-D-glucoside glucohydrolase
Comments: Wide specificity for β-D-glucosides. Some examples also hydrolyse one or more of the following: β-D-galactosides, α-L-arabinosides, β-D-xylosides, β-D-fucosides.
References:
1.  Chinchetru, M.A., Cabezas, J.A. and Calvo, P. Purification and characterization of a broad specificity β-glucosidase from sheep liver. Int. J. Biochem. 21 (1989) 469–476. [PMID: 2503402]
2.  Conchie, J. β-Glucosidase from rumen liquor. Preparation, assay and kinetics of action. Biochem. J. 58 (1954) 552–560. [PMID: 13230003]
3.  Dahlqvist, A. Pig intestinal β-glucosidase activities. I. Relation to β-galactosidase (lactase). Biochim. Biophys. Acta 50 (1961) 55–61. [PMID: 13719334]
4.  Heyworth, R. and Walker, P.G. Almond-emulsin β-D-glucosidase and β-D-galactosidase. Biochem. J. 83 (1962) 331–335. [PMID: 13907157]
5.  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.
6.  Sano, K., Amemura, A. and Harada, T. Purification and properties of a β-1,6-glucosidase from Flavobacterium. Biochim. Biophys. Acta 377 (1975) 410–420. [PMID: 235305]
[EC 3.2.1.21 created 1961]
 
 
EC 3.2.1.22     
Accepted name: α-galactosidase
Reaction: Hydrolysis of terminal, non-reducing α-D-galactose residues in α-D-galactosides, including galactose oligosaccharides, galactomannans and galactolipids
Other name(s): melibiase; α-D-galactosidase; α-galactosidase A; α-galactoside galactohydrolase
Systematic name: α-D-galactoside galactohydrolase
Comments: Also hydrolyses α-D-fucosides.
References:
1.  Suzuki, H., Li, S.-C. and Li, Y.-T. α-Galactosidase from Mortierella vinacea. Crystallization and properties. J. Biol. Chem. 245 (1970) 781–786. [PMID: 5418105]
2.  Wiederschain, G. and Beyer, E. [Interrelation of α-D-fucosidase and α-D-galactosidase activities in man and animals] Dokl. Akad. Nauk S.S.S.R. 231 (1976) 486–488. [PMID: 976079]
[EC 3.2.1.22 created 1961]
 
 
EC 3.2.1.23     
Accepted name: β-galactosidase
Reaction: Hydrolysis of terminal non-reducing β-D-galactose residues in β-D-galactosides
Other name(s): lactase (ambiguous); β-lactosidase; maxilact; hydrolact; β-D-lactosidase; S 2107; lactozym; trilactase; β-D-galactanase; oryzatym; sumiklat
Systematic name: β-D-galactoside galactohydrolase
Comments: Some enzymes in this group hydrolyse α-L-arabinosides; some animal enzymes also hydrolyse β-D-fucosides and β-D-glucosides; cf. EC 3.2.1.108 lactase.
References:
1.  Blakely, J.A. and MacKenzie, S.L. Purification and properties of a β-hexosidase from Sporobolomyces singularis. Can. J. Biochem. 47 (1969) 1021–1025. [PMID: 5389663]
2.  Kuby, S.A. and Lardy, H.A. Purification and kinetics of β-D-galactosidase from Escherichia coli, strain K-12. J. Am. Chem. Soc. 75 (1953) 890–896.
3.  Kuo, C.H. and Wells, W.W. β-Galactosidase from rat mammary gland. Its purification, properties, and role in the biosynthesis of 6β-O-D-galactopyranosyl myo-inositol. J. Biol. Chem. 253 (1978) 3550–3556. [PMID: 418065]
4.  Landman, O.E. Properties and induction of β-galactosidase in Bacillus megaterium. Biochim. Biophys. Acta 23 (1957) 558–569. [PMID: 13426167]
5.  Llanillo, M., Perez, N. and Cabezas, J.A. β-Galactosidase and β-glucosidase activities of the same enzyme from rabbit liver. Int. J. Biochem. 8 (1977) 557–564.
6.  Monod, J. and Cohn, M. La biosynthèse induite des enzymes (adaptation enzymatique). Adv. Enzymol. Relat. Subj. Biochem. 13 (1952) 67–119. [PMID: 14943665]
7.  Wallenfels, K. and Malhotra, O.P. In: Boyer, P.D., Lardy, H. and Myrbäck, K. (Ed.), The Enzymes, 2nd edn, vol. 4, Academic Press, New York, 1960, pp. 409–430.
8.  Asp, N.G., Dahlqvist, A. and Koldovský, O. Human small-intestinal β-galactosidases. Separation and characterization of one lactase and one hetero β-galactosidase. Biochem. J. 114 (1969) 351–359. [PMID: 5822067]
[EC 3.2.1.23 created 1961, modified 1980]
 
 
EC 3.2.1.24     
Accepted name: α-mannosidase
Reaction: Hydrolysis of terminal, non-reducing α-D-mannose residues in α-D-mannosides
Other name(s): α-D-mannosidase; p-nitrophenyl-α-mannosidase; α-D-mannopyranosidase; 1,2-α-mannosidase; 1,2-α-D-mannosidase; exo-α-mannosidase
Systematic name: α-D-mannoside mannohydrolase
Comments: Also hydrolyses α-D-lyxosides and heptopyranosides with the same configuration at C-2, C-3 and C-4 as mannose.
References:
1.  Li, Y.-T. Presence of α-D-mannosidic linkage in glycoproteins. Liberation of D-mannose from various glycoproteins by α-mannosidase isolated from jack bean meal. J. Biol. Chem. 241 (1966) 1010–1012. [PMID: 5905120]
2.  Winchester, B. Role of α-D-mannosidases in the biosynthesis and catabolism of glycoproteins. Biochem. Soc. Trans. 12 (1984) 522–524. [PMID: 6428944]
[EC 3.2.1.24 created 1961]
 
 
EC 3.2.1.25     
Accepted name: β-mannosidase
Reaction: Hydrolysis of terminal, non-reducing β-D-mannose residues in β-D-mannosides
Other name(s): mannanase; mannase; β-D-mannosidase; β-mannoside mannohydrolase; exo-β-D-mannanase
Systematic name: β-D-mannoside mannohydrolase
References:
1.  Adams, M., Richtmyer, N.K. and Hudson, C.S. Some enzymes present in highly purified invertase preparations; a contribution to the study of fructofuranosidases, galactosidases, glucosidases and mannosidases. J. Am. Chem. Soc. 65 (1943) 1369–1380.
2.  Bartholomew, B.A. and Perry, A.L. The properties of synovial fluid β-mannosidase activity. Biochim. Biophys. Acta 315 (1973) 123–127. [PMID: 4743897]
3.  Deuel, H., Lewuenberger, R. and Huber, G. Über den enzymatischen Abbau von Carubin, dem Galaktomannan aus Ceratonia siliqua L. Helv. Chim. Acta 33 (1950) 942–946.
4.  Hylin, J.W. and Sawai, K. The enzymatic hydrolysis of Leucaena glauca galactomannan. Isolation of crystalline galactomannan depolymerase. J. Biol. Chem. 239 (1964) 990–992. [PMID: 14165949]
[EC 3.2.1.25 created 1961]
 
 
EC 3.2.1.26     
Accepted name: β-fructofuranosidase
Reaction: Hydrolysis of terminal non-reducing β-D-fructofuranoside residues in β-D-fructofuranosides
Other name(s): invertase; saccharase; glucosucrase; β-h-fructosidase; β-fructosidase; invertin; sucrase; maxinvert L 1000; fructosylinvertase; alkaline invertase; acid invertase
Systematic name: β-D-fructofuranoside fructohydrolase
Comments: Substrates include sucrose; also catalyses fructotransferase reactions.
References:
1.  Myrbäck, K. Invertases. In: Boyer, P.D., Lardy, H. and Myrbäck, K. (Ed.), The Enzymes, 2nd edn, vol. 4, Academic Press, New York, 1960, pp. 379–396.
2.  Neumann, N.P. and Lampen, J.O. Purification and properties of yeast invertase. Biochemistry 6 (1967) 468–475. [PMID: 4963242]
[EC 3.2.1.26 created 1961]
 
 
EC 3.2.1.27      
Deleted entry:  α-1,3-glucosidase
[EC 3.2.1.27 created 1961, deleted 1972]
 
 
EC 3.2.1.28     
Accepted name: α,α-trehalase
Reaction: α,α-trehalose + H2O = β-D-glucose + α-D-glucose
Other name(s): trehalase
Systematic name: α,α-trehalose glucohydrolase
Comments: The enzyme is an anomer-inverting glucosidase that catalyses the hydrolysis of the α-glucosidic O-linkage of α,α-trehalose, releasing initially equimolar amounts of α- and β-D-glucose. It is widely distributed in microorganisms, plants, invertebrates and vertebrates.
References:
1.  Myrbäck, K. and Örtenblad, B. Trehalose und Hefe. II. Trehalasewirkung von Hefepräparaten. Biochem. Z. 291 (1937) 61–69.
2.  Kalf, G.F. and Rieder, S.V. The preparation and properties of trehalase. J. Biol. Chem. 230 (1958) 691–698. [PMID: 13525386]
3.  Hehre, E.J., Sawai, T., Brewer, C.F., Nakano, M. and Kanda, T. Trehalase: stereocomplementary hydrolytic and glucosyl transfer reactions with α- and β-D-glucosyl fluoride. Biochemistry 21 (1982) 3090–3097. [PMID: 7104311]
4.  Mori, H., Lee, J.H., Okuyama, M., Nishimoto, M., Ohguchi, M., Kim, D., Kimura, A. and Chiba, S. Catalytic reaction mechanism based on α-secondary deuterium isotope effects in hydrolysis of trehalose by European honeybee trehalase. Biosci. Biotechnol. Biochem. 73 (2009) 2466–2473. [PMID: 19897915]
[EC 3.2.1.28 created 1961, modified 2012]
 
 
EC 3.2.1.29      
Deleted entry:  chitobiase. Now included with EC 3.2.1.52, β-N-acetylhexosaminidase
[EC 3.2.1.29 created 1961, deleted 1972]
 
 
EC 3.2.1.30      
Deleted entry:  β-D-acetylglucosaminidase. Now included with EC 3.2.1.52, β-N-acetylhexosaminidase
[EC 3.2.1.30 created 1961, deleted 1992]
 
 
EC 3.2.1.31     
Accepted name: β-glucuronidase
Reaction: a β-D-glucuronoside + H2O = D-glucuronate + an alcohol
Other name(s): β-glucuronide glucuronohydrolase glucuronidase; exo-β-D-glucuronidase; ketodase
Systematic name: β-D-glucuronoside glucuronosohydrolase
References:
1.  Diez, T. and Cabezas, J.A. Properties of two molecular forms of β-glucuronidase from the mollusc Littorina littorea L. Eur. J. Biochem. 93 (1978) 301–311.
2.  Doyle, M.L., Katzman, P.A. and Doisy, E.A. Production and properties of bacterial β-glucuronidase. J. Biol. Chem. 217 (1955) 921–930. [PMID: 13271452]
3.  Fishman, W.H. Beta-glucuronidase. Adv. Enzymol. Relat. Subj. Biochem. 16 (1955) 361–409. [PMID: 14376216]
4.  Levvy, G.A. and Marsh, C.A. β-Glucuronidase. In: Boyer, P.D., Lardy, H. and Myrbäck, K. (Ed.), The Enzymes, 2nd edn, vol. 4, Academic Press, New York, 1960, pp. 397–407.
5.  Wakabayashi, M. and Fishman, W.H. The comparative ability of β-glucuronidase preparations (liver, Escherichia coli, Helix pomatia, and Patella vulgata) to hydrolyze certain steroid glucosiduronic acids. J. Biol. Chem. 236 (1961) 996–1001. [PMID: 13782588]
[EC 3.2.1.31 created 1961]
 
 
EC 3.2.1.32     
Accepted name: endo-1,3-β-xylanase
Reaction: Random endohydrolysis of (1→3)-β-D-glycosidic linkages in (1→3)-β-D-xylans
Other name(s): xylanase (ambiguous); endo-1,3-β-xylosidase (misleading); 1,3-β-xylanase; 1,3-xylanase; β-1,3-xylanase; endo-β-1,3-xylanase; 1,3-β-D-xylan xylanohydrolase; xylan endo-1,3-β-xylosidase
Systematic name: 3-β-D-xylan xylanohydrolase
Comments: This enzyme is found mostly in marine bacteria, which break down the β(1,3)-xylan found in the cell wall of some green and red algae. The enzyme produces mainly xylobiose, xylotriose and xylotetraose.
References:
1.  Chen, W.P., Matsuo, M. and Tsuneo, Y. Purification and some properties of β-1,3-xylanase from Aspergillus terreus A-07. Agric. Biol. Chem. 50 (1986) 1183–1194.
2.  Aoki, T., Araki, T. and Kitamikado, M. Purification and characterization of an endo-β-1,3-xylanase from Vibrio species. Nippon Suisan Gakkaishi 54 (1988) 277–281.
3.  Araki, T., Tani, S., Maeda, K., Hashikawa, S., Nakagawa, H. and Morishita, T. Purification and characterization of β-1,3-xylanase from a marine bacterium, Vibrio sp. XY-214. Biosci. Biotechnol. Biochem. 63 (1999) 2017–2019. [PMID: 10635569]
4.  Araki, T., Inoue, N. and Morishita, T. Purification and characterization of β-1,3-xylanase from a marine bacterium, Alcaligenes sp. XY-234. J. Gen. Appl. Microbiol. 44 (1998) 269–274. [PMID: 12501421]
5.  Okazaki, F., Shiraki, K., Tamaru, Y., Araki, T. and Takagi, M. The first thermodynamic characterization of β-1,3-xylanase from a marine bacterium. Protein J. 24 (2005) 413–421. [PMID: 16328734]
[EC 3.2.1.32 created 1965, modified 2011]
 
 
EC 3.2.1.33     
Accepted name: amylo-α-1,6-glucosidase
Reaction: Hydrolysis of (1→6)-α-D-glucosidic branch linkages in glycogen phosphorylase limit dextrin
Other name(s): amylo-1,6-glucosidase; dextrin 6-α-D-glucosidase; amylopectin 1,6-glucosidase; dextrin-1,6-glucosidase; glycogen phosphorylase-limit dextrin α-1,6-glucohydrolase
Systematic name: glycogen phosphorylase-limit dextrin 6-α-glucohydrolase
Comments: This enzyme hydrolyses an unsubstituted glucose unit linked by an α(1→6) bond to an α(1→4) glucose chain. The enzyme activity found in mammals and yeast is in a polypeptide chain containing two active centres. The other activity is similar to that of EC 2.4.1.25 (4-α-glucanotransferase), which acts on the glycogen phosphorylase limit dextrin chains to expose the single glucose residues, which the 6-α-glucosidase activity can then hydrolyse. Together, these two activities constitute the glycogen debranching system.
References:
1.  Brown, D.H. and Brown, B.I. Enzymes of glycogen debranching: Amylo-1,6-glucosidase (I) and oligo-1,4→1,4-glucanotransferase (II). Methods Enzymol. 8 (1966) 515–524.
2.  Lee, E.Y.C., Carter, J.H., Nielsen, L.D. and Fischer, E.H. Purification and properties of yeast amylo-1,6-glucosidase-oligo-1,4 leads to 1,4-glucantransferase. Biochemistry 9 (1970) 2347–2355. [PMID: 5424210]
3.  Nelson, T.E., Kolb, E. and Larner, J. Purification and properties of rabbit muscle amylo-1,6-glucosidase-oligo-1,4-1,4-transferase. Biochemistry 8 (1969) 1419–1428. [PMID: 5805288]
[EC 3.2.1.33 created 1965, modified 2000]
 
 
EC 3.2.1.34      
Deleted entry:  chondroitinase. Now included with EC 3.2.1.35 hyalurononglucosaminidase
[EC 3.2.1.34 created 1965, deleted 1972]
 
 
EC 3.2.1.35     
Accepted name: hyaluronoglucosaminidase
Reaction: Random hydrolysis of (1→4)-linkages between N-acetyl-β-D-glucosamine and D-glucuronate residues in hyaluronate
Other name(s): hyaluronidase; hyaluronoglucosidase; chondroitinase; chondroitinase I
Systematic name: hyaluronate 4-glycanohydrolase
Comments: Also hydrolyses 1,4-β-D-glycosidic linkages between N-acetyl-galactosamine or N-acetylgalactosamine sulfate and glucuronic acid in chondroitin, chondroitin 4- and 6-sulfates, and dermatan.
References:
1.  Meyer, K., Hoffman, P. and Linker, A. Hyaluronidases. In: Boyer, P.D., Lardy, H. and Myrbäck, K. (Ed.), The Enzymes, 2nd edn, vol. 4, Academic Press, New York, 1960, pp. 447–460.
2.  Rapport, M.M., Myer, K. and Linker, A. Analysis of the products formed on hydrolysis of hyaluronic acid by testicular hyaluronidase. J. Am. Chem. Soc. 73 (1951) 2416–2420.
3.  Weissmann, B. The transglycosylative action of testicular hyaluronidase. J. Biol. Chem. 216 (1955) 783–794. [PMID: 13271353]
[EC 3.2.1.35 created 1965, modified 1976, modified 2001 (EC 3.2.1.34 created 1965, incorporated 1972)]
 
 
EC 3.2.1.36     
Accepted name: hyaluronoglucuronidase
Reaction: Random hydrolysis of (1→3)-linkages between β-D-glucuronate and N-acetyl-D-glucosamine residues in hyaluronate
Other name(s): hyaluronidase; glucuronoglucosaminoglycan hyaluronate lyase; orgelase
Systematic name: hyaluronate 3-glycanohydrolase
References:
1.  Linker, A., Meyer, K. and Hoffman, P. The production of hyaluronate oligosaccharides by leech hyaluronidase and alkali. J. Biol. Chem. 235 (1960) 924–927. [PMID: 14417285]
2.  Meyer, K., Hoffman, P. and Linker, A. Hyaluronidases. In: Boyer, P.D., Lardy, H. and Myrbäck, K. (Ed.), The Enzymes, 2nd edn, vol. 4, Academic Press, New York, 1960, pp. 447–460.
[EC 3.2.1.36 created 1965, modified 1980]
 
 
EC 3.2.1.37     
Accepted name: xylan 1,4-β-xylosidase
Reaction: Hydrolysis of (1→4)-β-D-xylans, to remove successive D-xylose residues from the non-reducing termini
Other name(s): xylobiase; β-xylosidase; exo-1,4-β-xylosidase; β-D-xylopyranosidase; β-xylosidase; β-xylosidase; exo-1,4-xylosidase; exo-1,4-β-D-xylosidase; 1,4-β-D-xylan xylohydrolase
Systematic name: 4-β-D-xylan xylohydrolase
Comments: Also hydrolyses xylobiose. Some other exoglycosidase activities have been found associated with this enzyme in sheep liver.
References:
1.  Chinchetru, M.A., Cabezas, J.A. and Calvo, P. Purification and characterization of a broad specificity β-glucosidase from sheep liver. Int. J. Biochem. 21 (1989) 469–476. [PMID: 2503402]
2.  Howard, B.H., Jones, G. and Purdom, M.R. The pentosanases of some rumen bacteria. Biochem. J. 74 (1960) 173–180. [PMID: 14403433]
[EC 3.2.1.37 created 1965]
 
 
EC 3.2.1.38     
Accepted name: β-D-fucosidase
Reaction: Hydrolysis of terminal non-reducing β-D-fucose residues in β-D-fucosides
Other name(s): β-fucosidase
Systematic name: β-D-fucoside fucohydrolase
Comments: Enzymes from some sources also hydrolyse β-D-galactosides and/or β-D-glucosides and/or α-L-arabinosides. The activity of EC 3.2.1.37 xylan 1,4-β-xylosidase, is an associated activity found in some sources (e.g. liver).
References:
1.  Chinchetru, M.A., Cabezas, J.A. and Calvo, P. Characterization and kinetics of β-D-gluco/fuco/galactosidase from sheep liver. Comp. Biochem. Physiol. B 75 (1983) 719–728. [PMID: 6413126]
2.  Chinchetru, M.A., Cabezas, J.A. and Calvo, P. Purification and characterization of a broad specificity β-glucosidase from sheep liver. Int. J. Biochem. 21 (1989) 469–476. [PMID: 2503402]
3.  Rodriguez, J.A., Cabezas, J.A. and Calvo, P. β-Fucosidase, β-glucosidase and β-galactosidase activities associated in bovine liver. Int. J. Biochem. 14 (1982) 695–698. [PMID: 6811346]
4.  Wiederschain, G. and Prokopenkov, A. β-D-Galactosidase and β-D-fucosidase of pig kidney. Arch. Biochem. Biophys. 158 (1973) 539–543. [PMID: 4782520]
5.  Wiederschain, G.Y., Beyer, E.M., Klyaschitsty, B.A. and Shashkov, A.S. Specificity patterns of different types of human fucosidase. Recognition of a certain region of the pyranose ring in sugars by the enzymes. Biochim. Biophys. Acta 659 (1981) 434–444. [PMID: 6789883]
[EC 3.2.1.38 created 1965, deleted 1972, reinstated 1978]
 
 
EC 3.2.1.39     
Accepted name: glucan endo-1,3-β-D-glucosidase
Reaction: Hydrolysis of (1→3)-β-D-glucosidic linkages in (1→3)-β-D-glucans
Other name(s): endo-1,3-β-glucanase; laminarinase; laminaranase; oligo-1,3-glucosidase; endo-1,3-β-glucanase; callase; β-1,3-glucanase; kitalase; 1,3-β-D-glucan 3-glucanohydrolase; endo-(1,3)-β-D-glucanase; (1→3)-β-glucan 3-glucanohydrolase; endo-1,3-β-D-glucanase; endo-1,3-β-glucosidase; 1,3-β-D-glucan glucanohydrolase
Systematic name: 3-β-D-glucan glucanohydrolase
Comments: Different from EC 3.2.1.6 endo-1,3(4)-β-glucanase. Very limited action on mixed-link (1→3,1→4)-β-D-glucans. Hydrolyses laminarin, paramylon and pachyman.
References:
1.  Chesters, C.G.C. and Bull, A.T. The enzymic degradation of laminarin. 2. The multicomponent nature of fungal laminarinases. Biochem. J. 86 (1963) 31–38. [PMID: 14020682]
2.  Reese, E.T. and Mandels, M. β-D-1,3-Glucanases in fungi. Can. J. Microbiol. 5 (1959) 173–185. [PMID: 13638895]
[EC 3.2.1.39 created 1965]
 
 
EC 3.2.1.40     
Accepted name: α-L-rhamnosidase
Reaction: Hydrolysis of terminal non-reducing α-L-rhamnose residues in α-L-rhamnosides
Other name(s): α-L-rhamnosidase T; α-L-rhamnosidase N
Systematic name: α-L-rhamnoside rhamnohydrolase
Comments: The enzyme, found in animal tissues, plants, yeasts, fungi and bacteria, utilizes an inverting mechanism of hydrolysis, releasing β-L-rhamnose. Substrates include naringin, rutin, quercitrin, hesperidin, dioscin, terpenyl glycosides and many other natural glycosides containing terminal α-L-rhamnose.
References:
1.  Rosenfeld, E. and Wiederschein, G. The metabolism of L-rhamnose in animal tissues. Bull. Soc. Chim. Biol. 47 (1965) 1433–1440. [PMID: 5855461]
2.  Kurosawa, Y., Ikeda, K. and Egami, F. α-L-rhamnosidases of the liver of Turbo cornutus and Aspergillus niger. J. Biochem. 73 (1973) 31–37. [PMID: 4632197]
3.  Zverlov, V.V., Hertel, C., Bronnenmeier, K., Hroch, A., Kellermann, J. and Schwarz, W.H. The thermostable α-L-rhamnosidase RamA of Clostridium stercorarium: biochemical characterization and primary structure of a bacterial α-L-rhamnoside hydrolase, a new type of inverting glycoside hydrolase. Mol. Microbiol. 35 (2000) 173–179. [PMID: 10632887]
4.  Yanai, T. and Sato, M. Purification and characterization of an α-L-rhamnosidase from Pichia angusta X349. Biosci. Biotechnol. Biochem. 64 (2000) 2179–2185. [PMID: 11129592]
5.  Cui, Z., Maruyama, Y., Mikami, B., Hashimoto, W. and Murata, K. Crystal structure of glycoside hydrolase family 78 α-L-Rhamnosidase from Bacillus sp. GL1. J. Mol. Biol. 374 (2007) 384–398. [PMID: 17936784]
6.  Rabausch, U., Ilmberger, N. and Streit, W.R. The metagenome-derived enzyme RhaB opens a new subclass of bacterial B type α-L-rhamnosidases. J. Biotechnol. 191 (2014) 38–45. [PMID: 24815685]
[EC 3.2.1.40 created 1972]
 
 
EC 3.2.1.41     
Accepted name: pullulanase
Reaction: Hydrolysis of (1→6)-α-D-glucosidic linkages in pullulan, amylopectin and glycogen, and in the α- and β-limit dextrins of amylopectin and glycogen
Glossary: pullulan = a linear polymer of (1→6)-linked maltotriose units
Other name(s): limit dextrinase (erroneous); amylopectin 6-glucanohydrolase; bacterial debranching enzyme; debranching enzyme; α-dextrin endo-1,6-α-glucosidase; R-enzyme; pullulan α-1,6-glucanohydrolase
Systematic name: pullulan 6-α-glucanohydrolase
Comments: Different from EC 3.2.1.142 (limit dextrinase) in its action on glycogen, and its rate of hydrolysis of limit dextrins. Its action on amylopectin is complete. Maltose is the smallest sugar that it can release from an α-(1→6)-linkage.
References:
1.  Lee, E.Y.C. and Whelan, W.J. Glycogen and starch debranching enzymes. In: Boyer, P.D. (Ed.), The Enzymes, 3rd edn, vol. 5, Academic Press, New York, 1972, pp. 191–234.
2.  Bender, H. and Wallenfels, K. Pullulanase (an amylopectin and glycogen debranching enzyme) from Aerobacter aerogenes. Methods Enzymol. 8 (1966) 555–559.
3.  Manners, D.J. Observations on the specificity and nomenclature of starch debranching enzymes. J. Appl. Glycosci. 44 (1997) 83–85.
[EC 3.2.1.41 created 1972, modified 1976, modified 2000 (EC 3.2.1.69 created 1972, incorporated 1976)]
 
 
EC 3.2.1.42     
Accepted name: GDP-glucosidase
Reaction: GDP-glucose + H2O = D-glucose + GDP
Other name(s): guanosine diphosphoglucosidase; guanosine diphosphate D-glucose glucohydrolase
Systematic name: GDP-glucose glucohydrolase
References:
1.  Sonnino, S., Carinatti, H. and Cabib, E. Guanosine diphosphate D-glucose glucohydrolase. Arch. Biochem. Biophys. 116 (1966) 26–33. [PMID: 5963308]
[EC 3.2.1.42 created 1972]
 
 
EC 3.2.1.43     
Accepted name: β-L-rhamnosidase
Reaction: Hydrolysis of terminal, non-reducing β-L-rhamnose residues in β-L-rhamnosides
Systematic name: β-L-rhamnoside rhamnohydrolase
References:
1.  Barker, S.A., Somers, P.J. and Stacey, M. Arrangement of the L-rhamnose units in Diplococcus pneumoniae type II polysaccharide. Carbohydr. Res. 1 (1965) 106–115.
[EC 3.2.1.43 created 1972]
 
 
EC 3.2.1.44      
Transferred entry: fucoidanase. Now EC 3.2.1.211, endo-(13)-fucoidanase and EC 3.2.1.212, endo-(14)-fucoidanase
[EC 3.2.1.44 created 1972, deleted 2020]
 
 
EC 3.2.1.45     
Accepted name: glucosylceramidase
Reaction: a D-glucosyl-N-acylsphingosine + H2O = D-glucose + a ceramide
Glossary: a ceramide = an N-acylsphingosine
Other name(s): psychosine hydrolase; glucosphingosine glucosylhydrolase; GlcCer-β-glucosidase; β-D-glucocerebrosidase; glucosylcerebrosidase; β-glucosylceramidase; ceramide glucosidase; glucocerebrosidase; glucosylsphingosine β-glucosidase; glucosylsphingosine β-D-glucosidase
Systematic name: D-glucosyl-N-acylsphingosine glucohydrolase
Comments: Also acts on glucosylsphingosine (cf. EC 3.2.1.62 glycosylceramidase).
References:
1.  Brady, R.O., Kanfer, J.N. and Shapiro, D. The metabolism of glucocerebrosides. I. Preparation and properties of a glucocerebroside-cleaving enzyme from spleen tissue. J. Biol. Chem. 240 (1966) 39–43. [PMID: 14253443]
2.  Vaccaro, A.M., Muscillo, M. and Suzuki, K. Characterization of human glucosylsphingosine glucosyl hydrolase and comparison with glucosylceramidase. Eur. J. Biochem. 146 (1985) 315–321. [PMID: 3967661]
[EC 3.2.1.45 created 1972]
 
 
EC 3.2.1.46     
Accepted name: galactosylceramidase
Reaction: a D-galactosyl-N-acylsphingosine + H2O = D-galactose + a ceramide
Glossary: a ceramide = an N-acylsphingosine
Other name(s): cerebroside galactosidase; galactocerebroside.β-galactosidase; galactosylcerebrosidase; galactocerebrosidase; ceramide galactosidase; galactocerebroside galactosidase; galactosylceramide.β-galactosidase; cerebroside β-galactosidase; galactosylceramidase I; β-galactosylceramidase; galactocerebroside-β-D-galactosidase; lactosylceramidase I; β-galactocerebrosidase; lactosylceramidase
Systematic name: D-galactosyl-N-acylsphingosine galactohydrolase
Comments: cf. EC 3.2.1.62 glycosylceramidase.
References:
1.  Brady, R.O., Gal, A.E., Kanfer, J.N. and Bradley, R.M. The metabolism of glucocerebrosides. 3. Purification and properties of a glucosyl- and galactosylceramide-cleaving enzyme from rat intestinal tissue. J. Biol. Chem. 240 (1965) 3766–3770. [PMID: 5320641]
[EC 3.2.1.46 created 1972]
 
 
EC 3.2.1.47      
Deleted entry: galactosylgalactosylglucosylceramidase. Now known to be catalyzed by EC 3.2.1.22, α-galactosidase.
[EC 3.2.1.47 created 1972, modified 2011, deleted 2021]
 
 
EC 3.2.1.48     
Accepted name: sucrose α-glucosidase
Reaction: Hydrolysis of sucrose and maltose by an α-D-glucosidase-type action
Other name(s): sucrose α-glucohydrolase; sucrase; sucrase-isomaltase; sucrose.α.-glucohydrolase; intestinal sucrase; sucrase(invertase)
Systematic name: sucrose-α-D-glucohydrolase
Comments: This enzyme is isolated from intestinal mucosa as a single polypeptide chain that also displays activity towards isomaltose (EC 3.2.1.10 oligo-1,6-glucosidase).
References:
1.  Conklin, K.A., Yamashiro, K.M. and Gray, G.M. Human intestinal sucrase-isomaltase. Identification of free sucrase and isomaltase and cleavage of the hybrid into active distinct subunits. J. Biol. Chem. 250 (1975) 5735–5741. [PMID: 807575]
2.  Hauri, H.-P., Quaroni, A. and Isselbacher, K.J. Biogenesis of intestinal plasma membrane: posttranslational route and cleavage of sucrase-isomaltase. Proc. Natl. Acad. Sci. USA 76 (1979) 5183–5186. [PMID: 291933]
3.  Kolinska, J. and Kraml, J. Separation and characterization of sucrose-isomaltase and of glucoamylase of rat intestine. Biochim. Biophys. Acta 284 (1972) 235–247. [PMID: 5073761]
4.  Sigrist, H., Ronner, P. and Semenza, G. A hydrophobic form of the small-intestinal sucrase-isomaltase complex. Biochim. Biophys. Acta 406 (1975) 433–446. [PMID: 1182172]
5.  Sjöström, H., Norén, O., Christiansen, L., Wacker, H. and Semenza, G. A fully active, two-active-site, single-chain sucrase-isomaltase from pig small intestine. Implications for the biosynthesis of a mammalian integral stalked membrane protein. J. Biol. Chem. 255 (1980) 11332–11338. [PMID: 7002920]
6.  Takesue, Y. Purification and properties of rabbit intestinal sucrase. J. Biochem. (Tokyo) 65 (1969) 545–552. [PMID: 5804876]
[EC 3.2.1.48 created 1972]
 
 
EC 3.2.1.49     
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.
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. [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. [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. [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. [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. [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. [PMID: 11368317]
[EC 3.2.1.49 created 1972, modified 2011]
 
 
EC 3.2.1.50     
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.
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. [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. [PMID: 5348072]
[EC 3.2.1.50 created 1972]
 
 
EC 3.2.1.51     
Accepted name: α-L-fucosidase
Reaction: an α-L-fucoside + H2O = L-fucose + an alcohol
Other name(s): α-fucosidase
Systematic name: α-L-fucoside fucohydrolase
References:
1.  Levvy, G.A. and McAllan, A. Mammalian fucosidases. 2. α-L-Fucosidase. Biochem. J. 80 (1961) 435–439. [PMID: 13761578]
2.  Reglero, A. and Cabezas, J.A. Glycosidases of molluscs. Purification and properties of α-L-fucosidase from Chamelea gallina L. Eur. J. Biochem. 66 (1976) 379–387. [PMID: 7458]
3.  Tanaka, K., Nakano, T., Noguchi, S. and Pigman, W. Purification of α-L-fucosidase of abalone livers. Arch. Biochem. Biophys. 126 (1968) 624–633. [PMID: 5672520]
[EC 3.2.1.51 created 1972]
 
 
EC 3.2.1.52     
Accepted name: β-N-acetylhexosaminidase
Reaction: Hydrolysis of terminal non-reducing N-acetyl-D-hexosamine residues in N-acetyl-β-D-hexosaminides
Other name(s): hexosaminidase; β-acetylaminodeoxyhexosidase; N-acetyl-β-D-hexosaminidase; N-acetyl-β-hexosaminidase; β-hexosaminidase; β-acetylhexosaminidinase; β-D-N-acetylhexosaminidase; β-N-acetyl-D-hexosaminidase; β-N-acetylglucosaminidase; hexosaminidase A; N-acetylhexosaminidase; β-D-hexosaminidase
Systematic name: β-N-acetyl-D-hexosaminide N-acetylhexosaminohydrolase
Comments: Acts on N-acetylglucosides and N-acetylgalactosides.
References:
1.  Cabezas, J.A. Some comments on the type references of the official nomenclature (IUB) for β-N-acetylglucosaminidase, β-N-acetylhexosaminidase and β-N-acetylgalactosaminidase. Biochem. J. 261 (1989) 1059–1060. [PMID: 2529847]
2.  Calvo, P., Reglero, A. and Cabezas, J.A. Purification and properties of β-N-acetylhexosaminidase from the mollusc Helicella ericetorum Muller. Biochem. J. 175 (1978) 743–750. [PMID: 33660]
3.  Frohwein, Y.S. and Gatt, S. Isolation of β-N-acetylhexosaminidase, β-N-acetylglucosaminidase, and β-N-acetylgalactosaminidase from calf brain. Biochemistry 6 (1967) 2775–2782. [PMID: 6055190]
4.  Li, S.-C. and Li, Y.-T. Studies on the glycosidases of jack bean meal. 3. Crystallization and properties of β-N-acetylhexosaminidase. J. Biol. Chem. 245 (1970) 5153–5160. [PMID: 5506280]
[EC 3.2.1.52 created 1972 (EC 3.2.1.30 created 1961, incorporated 1992 [EC 3.2.1.29 created 1961, incorporated 1972])]
 
 
EC 3.2.1.53     
Accepted name: β-N-acetylgalactosaminidase
Reaction: Hydrolysis of terminal non-reducing N-acetyl-D-galactosamine residues in N-acetyl-β-D-galactosaminides
Other name(s): N-acetyl-β-galactosaminidase; N-acetyl-β-D-galactosaminidase; β-acetylgalactosaminidase; β-D-N-acetylgalactosaminidase; N-acetylgalactosaminidase
Systematic name: β-N-acetyl-D-galactosaminide N-acetylgalactosaminohydrolase
References:
1.  Frohwein, Y.S. and Gatt, S. Isolation of β-N-acetylhexosaminidase, β-N-acetylglucosaminidase, and β-N-acetylgalactosaminidase from calf brain. Biochemistry 6 (1967) 2775–2782. [PMID: 6055190]
2.  Hoogwinkel, G.J.M., Veltkamp, W.A., Overdijk, B. and Lisman, J.W. Electrophoretic separation of β-N-acetylhexosaminidases of human and bovine brain and liver and of Tay-Sachs brain tissue. Hoppe-Seylers Z. Physiol. Chem. 353 (1972) 839–841. [PMID: 5069351]
[EC 3.2.1.53 created 1972]
 
 
EC 3.2.1.54     
Accepted name: cyclomaltodextrinase
Reaction: cyclomaltodextrin + H2O = linear maltodextrin
Other name(s): cycloheptaglucanase; cyclohexaglucanase; cyclodextrinase; cyclomaltodextrin dextrin-hydrolase (decyclizing)
Systematic name: cyclomaltodextrin dextrin-hydrolase (ring-opening)
Comments: Also hydrolyses linear maltodextrin.
References:
1.  DePinto, J.A. and Campbell, L.L. Purification and properties of the cyclodextrinase of Bacillus macerans. Biochemistry 7 (1968) 121–125. [PMID: 4922856]
[EC 3.2.1.54 created 1972 (EC 3.2.1.12 and EC 3.2.1.13 both created 1961 and incorporated 1976)]
 
 
EC 3.2.1.55     
Accepted name: non-reducing end α-L-arabinofuranosidase
Reaction: Hydrolysis of terminal non-reducing α-L-arabinofuranoside residues in α-L-arabinosides.
Other name(s): arabinosidase (ambiguous); α-arabinosidase; α-L-arabinosidase; α-arabinofuranosidase; polysaccharide α-L-arabinofuranosidase; α-L-arabinofuranoside hydrolase; L-arabinosidase (ambiguous); α-L-arabinanase
Systematic name: α-L-arabinofuranoside non-reducing end α-L-arabinofuranosidase
Comments: The enzyme acts on α-L-arabinofuranosides, α-L-arabinans containing (1,3)- and/or (1,5)-linkages, arabinoxylans and arabinogalactans. Some β-galactosidases (EC 3.2.1.23) and β-D-fucosidases (EC 3.2.1.38) also hydrolyse α-L-arabinosides. cf. EC 3.2.1.185, non-reducing end β-L-arabinofuranosidase.
References:
1.  Tagawa, K. and Kaji, A. Preparation of L-arabinose-containing polysaccharides and the action of an α-L-arabinofuranosidase on these polysaccharides. Carbohydr. Res. 11 (1969) 293–301.
2.  Kaji, A. and Tagawa, K. Purification, crystallization and amino acid composition of α-L-arabinofuranosidase from Aspergillus niger. Biochim. Biophys. Acta 207 (1970) 456–464. [PMID: 5452669]
3.  Kaji, A. and Yoshihara, O. Properties of purified α-L-arabinofuranosidase from Corticium rolfsii. Biochim. Biophys. Acta 250 (1971) 367–371. [PMID: 5143344]
4.  Margolles-Clark, E., Tenkanen, M., Nakari-Setala, T. and Penttila, M. Cloning of genes encoding α-L-arabinofuranosidase and β-xylosidase from Trichoderma reesei by expression in Saccharomyces cerevisiae. Appl. Environ. Microbiol. 62 (1996) 3840–3846. [PMID: 8837440]
5.  Inacio, J.M., Correia, I.L. and de Sa-Nogueira, I. Two distinct arabinofuranosidases contribute to arabino-oligosaccharide degradation in Bacillus subtilis. Microbiology 154 (2008) 2719–2729. [PMID: 18757805]
[EC 3.2.1.55 created 1972, modified 1976 (EC 3.2.1.79 created 1972, incorporated 1976), modified 2013]
 
 
EC 3.2.1.56     
Accepted name: glucuronosyl-disulfoglucosamine glucuronidase
Reaction: 3-D-glucuronosyl-N2,6-disulfo-β-D-glucosamine + H2O = D-glucuronate + N2,6-disulfo-D-glucosamine
Other name(s): glycuronidase; 3-D-glucuronsyl-2-N,6-disulfo-β-D-glucosamine glucuronohydrolase
Systematic name: 3-D-glucuronsyl-N2,6-disulfo-β-D-glucosamine glucuronohydrolase
References:
1.  Dietrich, C.P. Enzymic degradation of heparin. A glucosaminidase and a glycuronidase from Flavobacterium heparinum. Biochemistry 8 (1969) 2089–2094. [PMID: 5785227]
[EC 3.2.1.56 created 1972]
 
 
EC 3.2.1.57     
Accepted name: isopullulanase
Reaction: Hydrolysis of pullulan to isopanose (6-α-maltosylglucose)
Glossary: pullulan = a linear polymer of (1→6)-linked maltotriose units
Systematic name: pullulan 4-glucanohydrolase (isopanose-forming)
Comments: The enzyme has practically no action on starch. Panose (4-α-isomaltosylglucose) is hydrolysed to isomaltose and glucose. cf. EC 3.2.1.41 (pullulanase) and EC 3.2.1.135 (neopullulanase).
References:
1.  Sakano, Y., Masuda, N. and Kobayashi, T. Hydrolysis of pullulan by a novel enzyme from Aspergillus niger. Agric. Biol. Chem. 35 (1971) 971–973.
[EC 3.2.1.57 created 1972]
 
 
EC 3.2.1.58     
Accepted name: glucan 1,3-β-glucosidase
Reaction: Successive hydrolysis of β-D-glucose units from the non-reducing ends of (1→3)-β-D-glucans, releasing α-glucose
Other name(s): exo-1,3-β-glucosidase; β-1,3-glucan exo-hydrolase; exo (1→3)-glucanohydrolase; 1,3-β-glucan glucohydrolase
Systematic name: 3-β-D-glucan glucohydrolase
Comments: Acts on oligosaccharides, but very slowly on laminaribiose.
References:
1.  Barras, D.R. and Stone, B.A. β-1,3-Glucan hydrolases from Euglena gracilis. I. The nature of the hydrolases. Biochim. Biophys. Acta 191 (1969) 329–341. [PMID: 5354264]
2.  Barras, D.R. and Stone, B.A. β-1,3-Glucan hydrolases from Euglena gracilis. II. Purification and properties of the β-1,3-glucan exo-hydrolase. Biochim. Biophys. Acta 191 (1969) 342–353. [PMID: 5354265]
[EC 3.2.1.58 created 1972]
 
 
EC 3.2.1.59     
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.
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 3.2.1.60     
Accepted name: glucan 1,4-α-maltotetraohydrolase
Reaction: Hydrolysis of (1→4)-α-D-glucosidic linkages in amylaceous polysaccharides, to remove successive maltotetraose residues from the non-reducing chain ends
Other name(s): exo-maltotetraohydrolase; 1,4-α-D-glucan maltotetraohydrolase
Systematic name: 4-α-D-glucan maltotetraohydrolase
Comments: Compare EC 3.2.1.2 β-amylase, which removes successive maltose residues, and EC 3.2.1.98 (glucan 1,4-α-maltohexaosidase) and EC 3.2.1.116 (glucan 1,4-α-maltotriohydrolase).
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.
2.  Robyt, J.F. and Ackerman, R.J. Isolation, purification, and characterization of a maltotetraose-producing amylase from Pseudomonas stutzeri. Arch. Biochem. Biophys. 145 (1971) 105–114. [PMID: 5123132]
[EC 3.2.1.60 created 1972]
 
 
EC 3.2.1.61     
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.
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. [PMID: 5652425]
[EC 3.2.1.61 created 1972]
 
 
EC 3.2.1.62     
Accepted name: glycosylceramidase
Reaction: a glycosyl-N-acylsphingosine + H2O = a ceramide + a sugar
Glossary: a ceramide = an N-acylsphingosine
Other name(s): phlorizin hydrolase; phloretin-glucosidase; glycosyl ceramide glycosylhydrolase; cerebrosidase; phloridzin β-glucosidase; lactase-phlorizin hydrolase; phloridzin glucosidase
Systematic name: glycosyl-N-acylsphingosine glycohydrolase
Comments: Broad specificity [cf. EC 3.2.1.45 (glucosylceramidase) and EC 3.2.1.46 (galactosylceramidase)]. Also hydrolyses phlorizin to phloretin and glucose. The intestinal enzyme is a complex that also catalyses the reaction of EC 3.2.1.108 lactase.
References:
1.  Leese, H.J. and Semenza, G. On the identity between the small intestinal enzymes phlorizin hydrolase and glycosylceramidase. J. Biol. Chem. 248 (1973) 8170–8173. [PMID: 4752949]
2.  Lorenz-Meyer, H., Blum, A.L., Haemmerli, H.P. and Semenza, G. A second enzyme defect in acquired lactase deficiency: lack of small-intestinal phlorizin-hydrolase. Eur. J. Clin. Invest. 2 (1972) 326–331. [PMID: 5082068]
3.  Malathi, P. and Crane, R.K. Phlorizin hydrolase: a β-glucosidase of hamster intestinal brush border membrane. Biochim. Biophys. Acta 173 (1969) 245–256. [PMID: 5774775]
[EC 3.2.1.62 created 1972, modified 1976]
 
 
EC 3.2.1.63     
Accepted name: 1,2-α-L-fucosidase
Reaction: methyl-2-α-L-fucopyranosyl-β-D-galactoside + H2O = L-fucose + methyl β-D-galactoside
Other name(s): almond emulsin fucosidase; α-(1→2)-L-fucosidase
Systematic name: 2-α-L-fucopyranosyl-β-D-galactoside fucohydrolase
Comments: Highly specific for non-reducing terminal L-fucose residues linked to D-galactose residues by a 1,2-α-linkage. Not identical with EC 3.2.1.111 1,3-α-L-fucosidase.
References:
1.  Bahl, O.P. Glycosidases of Aspergillus niger. II. Purification and general properties of 1,2-α-L-fucosidase. J. Biol. Chem. 245 (1970) 299–304. [PMID: 5460888]
2.  Ogata-Arakawa, M., Muramatsu, T. and Kobata, A. α-L-Fucosidases from almond emulsin: characterization of the two enzymes with different specificities. Arch. Biochem. Biophys. 181 (1977) 353–358. [PMID: 18111]
3.  Reglero, A. and Cabezas, J.A. Glycosidases of molluscs. Purification and properties of α-L-fucosidase from Chamelea gallina L. Eur. J. Biochem. 66 (1976) 379–387. [PMID: 7458]
[EC 3.2.1.63 created 1972]
 
 
EC 3.2.1.64     
Accepted name: 2,6-β-fructan 6-levanbiohydrolase
Reaction: Hydrolysis of (2→6)-β-D-fructofuranan, to remove successive disaccharide residues as levanbiose, i.e. 6-(β-D-fructofuranosyl)-D-fructose, from the end of the chain
Other name(s): β-2,6-fructan-6-levanbiohydrolase; 2,6-β-D-fructan 6-levanbiohydrolase; levanbiose-producing levanase; 2,6-β-D-fructan 6-β-D-fructofuranosylfructohydrolase
Systematic name: (2→6)-β-D-fructofuranan 6-(β-D-fructosyl)-D-fructose-hydrolase
References:
1.  Avigad, G. and Zelikson, R. Cleavage of fructans to levanbiose by a specific hydrolase. Bull. Res. Counc. Isr. 11 (1963) 253–257.
2.  Saito, K., Kondo, K., Kojima, I., Yokota, A. and Tomita, F. Purification and characterization of 2,6-β-D-fructan 6-levanbiohydrolase from Streptomyces exfoliatus F3-2. Appl. Environ. Microbiol. 66 (2000) 252–256. [PMID: 10618232]
3.  Saito, K., Oda, Y., Tomita, F. and Yokota, A. Molecular cloning of the gene for 2,6-β-D-fructan 6-levanbiohydrolase from Streptomyces exfoliatus F3-2. FEMS Microbiol. Lett. 218 (2003) 265–270. [PMID: 12586402]
4.  Song, E.K., Kim, H., Sung, H.K. and Cha, J. Cloning and characterization of a levanbiohydrolase from Microbacterium laevaniformans ATCC 15953. Gene 291 (2002) 45–55. [PMID: 12095678]
5.  Kang, E.J., Lee, S.O., Lee, J.D., Lee, T.H. and Lee, T.H. Purification and characterization of a levanbiose-producing levanase from Pseudomonas sp. No. 43. Biotechnol. Appl. Biochem. 29 (1999) 263–268. [PMID: 10334957]
[EC 3.2.1.64 created 1972, modified 2004]
 
 
EC 3.2.1.65     
Accepted name: levanase
Reaction: Random hydrolysis of (2→6)-β-D-fructofuranosidic linkages in (2→6)-β-D-fructans (levans) containing more than 3 fructose units
Other name(s): levan hydrolase; 2,6-β-D-fructan fructanohydrolase
Systematic name: (2→6)-β-D-fructan fructanohydrolase
References:
1.  Avigad, G. and Bauer, S. Fructan hydrolases. Methods Enzymol. 8 (1966) 621–628.
[EC 3.2.1.65 created 1972]
 
 
EC 3.2.1.66     
Accepted name: quercitrinase
Reaction: quercitrin + H2O = L-rhamnose + quercetin
Systematic name: quercitrin 3-L-rhamnohydrolase
Comments: Quercitrin is quercetin 3-L-rhamnoside.
References:
1.  Westlake, D.W.S. Microbiological degradation of quercitrin. Can. J. Microbiol. 9 (1963) 211–220.
[EC 3.2.1.66 created 1972]
 
 
EC 3.2.1.67     
Accepted name: galacturonan 1,4-α-galacturonidase
Reaction: [(1→4)-α-D-galacturonide]n + H2O = [(1→4)-α-D-galacturonide]n-1 + D-galacturonate
Other name(s): exo-polygalacturonase; poly(galacturonate) hydrolase (ambiguous); exo-D-galacturonase; exo-D-galacturonanase; exopoly-D-galacturonase; poly(1,4-α-D-galacturonide) galacturonohydrolase (ambiguous); pgaA (gene name); pgaB (gene name); pgaC (gene name); pgaD (gene name); pgaE (gene name); pgaI (gene name); pgaII (gene name); poly[(1→4)-α-D-galacturonide] galacturonohydrolase; galacturan 1,4-α-galacturonidase (incorrect)
Systematic name: poly[(1→4)-α-D-galacturonide] non-reducing-end galacturonohydrolase
Comments: The enzyme hydrolyses the first glycosidic bond from the non-reducing end of the substrate. It is specific for saturated oligomers of D-homogalacturonan, and is unable to degrade unsaturated substrates or methyl-esterified substrates.
References:
1.  Hasegawa, H. and Nagel, C.W. Isolation of an oligogalacturonate hydrolase from a Bacillus species. Arch. Biochem. Biophys. 124 (1968) 513–520. [PMID: 5661621]
2.  Kluskens, L.D., van Alebeek, G.J., Walther, J., Voragen, A.G., de Vos, W.M. and van der Oost, J. Characterization and mode of action of an exopolygalacturonase from the hyperthermophilic bacterium Thermotoga maritima. FEBS J. 272 (2005) 5464–5473. [PMID: 16262687]
3.  Martens-Uzunova, E.S., Zandleven, J.S., Benen, J.A., Awad, H., Kools, H.J., Beldman, G., Voragen, A.G., Van den Berg, J.A. and Schaap, P.J. A new group of exo-acting family 28 glycoside hydrolases of Aspergillus niger that are involved in pectin degradation. Biochem. J. 400 (2006) 43–52. [PMID: 16822232]
4.  Pijning, T., van Pouderoyen, G., Kluskens, L., van der Oost, J. and Dijkstra, B.W. The crystal structure of a hyperthermoactive exopolygalacturonase from Thermotoga maritima reveals a unique tetramer. FEBS Lett. 583 (2009) 3665–3670. [PMID: 19854184]
[EC 3.2.1.67 created 1972, modified 2019]
 
 
EC 3.2.1.68     
Accepted name: isoamylase
Reaction: Hydrolysis of (1→6)-α-D-glucosidic branch linkages in glycogen, amylopectin and their β-limit dextrins
Glossary: pullulan = a linear polymer of (1→6)-linked maltotriose units
Other name(s): debranching enzyme; glycogen α-1,6-glucanohydrolase
Systematic name: glycogen 6-α-D-glucanohydrolase
Comments: Also readily hydrolyses amylopectin. Differs from EC 3.2.1.41 (pullulanase) and EC 3.2.1.142 (limit dextrinase) by its inability to hydrolyse pullulan, and by limited action on α-limit dextrins. Maltose is the smallest sugar it can release from an α-(1→6)-linkage.
References:
1.  Yokobayashi, K., Misaki, A. and Harada, T. Purification and properties of Pseudomonas isoamylase. Biochim. Biophys. Acta 212 (1970) 458–469. [PMID: 5456995]
[EC 3.2.1.68 created 1972, modified 1976, modified 2000]
 
 
EC 3.2.1.69      
Deleted entry:  amylopectin 6-glucanohydrolase. Now included with EC 3.2.1.41 pullulanase
[EC 3.2.1.69 created 1972, deleted 1976]
 
 
EC 3.2.1.70     
Accepted name: glucan 1,6-α-glucosidase
Reaction: Hydrolysis of (1→6)-α-D-glucosidic linkages in (1→6)-α-D-glucans and derived oligosaccharides
Other name(s): exo-1,6-β-glucosidase; glucodextrinase; glucan α-1,6-D-glucohydrolase
Systematic name: glucan 6-α-D-glucohydrolase
Comments: Hydrolysis is accompanied by inversion at C-1, so that new reducing ends are released in the β-configuration. Dextrans and isomaltosaccharides are hydrolysed, as is isomaltose, but very slowly. The enzyme from some sources also possesses the activity of EC 3.2.1.59 (glucan endo-1,3-α-glucosidase).
References:
1.  Ohya, T., Sawai, T., Uemura, S. and Abe, K. Some catalytic properties of an exo-1,6-α-glucosidase (glucodextranase) from Arthrobacter globiformis I42. Agric. Biol. Chem. 42 (1978) 571–577.
2.  Sawai, T., Yamaki, T. and Ohya, T. Preparation and some properties of Arthrobacter globiformis exo-1,6-α-glucosidase. Agric. Biol. Chem. 40 (1976) 1293–1299.
3.  Walker, G.J. and Pulkownik, A. Degradation of dextrans by an α-1,6-glucan glucohydrolase from Streptococcus mitis. Carbohydr. Res. 29 (1973) 1–14. [PMID: 4356399]
[EC 3.2.1.70 created 1972, modified 2001]
 
 
EC 3.2.1.71     
Accepted name: glucan endo-1,2-β-glucosidase
Reaction: Random hydrolysis of (1→2)-glucosidic linkages in (1→2)-β-D-glucans
Other name(s): endo-1,2-β-glucanase; β-D-1,2-glucanase; endo-(1→2)-β-D-glucanase; 1,2-β-D-glucan glucanohydrolase
Systematic name: 2-β-D-glucan glucanohydrolase
References:
1.  Reese, E.T., Parrish, F.W. and Mandels, M. β-D-1,2-Glucanases in fungi. Can. J. Microbiol. 7 (1961) 309–317. [PMID: 13740314]
[EC 3.2.1.71 created 1972]
 
 
EC 3.2.1.72     
Accepted name: xylan 1,3-β-xylosidase
Reaction: Hydrolysis of successive xylose residues from the non-reducing termini of (1→3)-β-D-xylans
Other name(s): 1,3-β-D-xylosidase; exo-1,3-β-xylosidase; β-1,3′-xylanase; exo-β-1,3′-xylanase; 1,3-β-D-xylan xylohydrolase
Systematic name: 3-β-D-xylan xylohydrolase
References:
1.  Fukui, S., Suzuki, T., Kitahara, K. and Miwa, T. β-1,3′-Xylanase. J. Gen. Appl. Microbiol. 6 (1960) 270–282.
[EC 3.2.1.72 created 1972]
 
 
EC 3.2.1.73     
Accepted name: licheninase
Reaction: Hydrolysis of (1→4)-β-D-glucosidic linkages in β-D-glucans containing (1→3)- and (1→4)-bonds
Other name(s): lichenase; β-(1→4)-D-glucan 4-glucanohydrolase; 1,3;1,4-β-glucan endohydrolase; 1,3;1,4-β-glucan 4-glucanohydrolase; 1,3-1,4-β-D-glucan 4-glucanohydrolase
Systematic name: (1→3)-(1→4)-β-D-glucan 4-glucanohydrolase
Comments: Acts on lichenin and cereal β-D-glucans, but not on β-D-glucans containing only 1,3- or 1,4-bonds.
References:
1.  Barras, D.R., Moore, A.E. and Stone, B.A. Enzyme-substrate relations among β-glucan hydrolases. Adv. Chem. Ser. 95 (1969) 105–138.
[EC 3.2.1.73 created 1972]
 
 
EC 3.2.1.74     
Accepted name: glucan 1,4-β-glucosidase
Reaction: Hydrolysis of (1→4)-linkages in (1→4)-β-D-glucans, to remove successive glucose units
Other name(s): exo-1,4-β-glucosidase; exocellulase; exo-β-1,4-glucosidase; exo-β-1,4-glucanase; β-1,4-β-glucanase; β-glucosidase; exo-1,4-β-glucanase; 1,4-β-D-glucan glucohydrolase
Systematic name: 4-β-D-glucan glucohydrolase
Comments: Acts on 1,4-β-D-glucans and related oligosaccharides. Cellobiose is hydrolysed, but very slowly.
References:
1.  Barras, D.R., Moore, A.E. and Stone, B.A. Enzyme-substrate relations among β-glucan hydrolases. Adv. Chem. Ser. 95 (1969) 105–138.
[EC 3.2.1.74 created 1972]
 
 
EC 3.2.1.75     
Accepted name: glucan endo-1,6-β-glucosidase
Reaction: Random hydrolysis of (1→6)-linkages in (1→6)-β-D-glucans
Other name(s): endo-1,6-β-glucanase; β-1→6)-β-D-glucanase; β-1,6-glucanase-pustulanase; β-1,6-glucan hydrolase; β-1,6-glucan 6-glucanohydrolase; 1,6-β-D-glucan glucanohydrolase
Systematic name: 6-β-D-glucan glucanohydrolase
Comments: Acts on lutean, pustulan and 1,6-oligo-β-D-glucosides.
References:
1.  Reese, E.T., Parrish, F.W. and Mandels, M. β-D-1,6-Glucanases in fungi. Can. J. Microbiol. 8 (1962) 327–334. [PMID: 14491003]
[EC 3.2.1.75 created 1972]
 
 
EC 3.2.1.76     
Accepted name: L-iduronidase
Reaction: Hydrolysis of unsulfated α-L-iduronosidic linkages in dermatan sulfate
Other name(s): α-L-iduronidase
Systematic name: glycosaminoglycan α-L-iduronohydrolase
References:
1.  Matalon, R., Cifonelli, J.A. and Dorfman, A. L-Iduronidase in cultured human fibroblasts and liver. Biochem. Biophys. Res. Commun. 42 (1971) 340–345. [PMID: 4993544]
2.  Rome, L.H., Garvin, A.J. and Neufeld, E.F. Human kidney α-L-iduronidase: purification and characterization. Arch. Biochem. Biophys. 189 (1978) 344–353. [PMID: 30407]
3.  Srivastava, R.M., Hudson, N., Seymour, F.R. and Weissman, B. Preparation of (aryl α-L-idopyranosid)uronic acids. Carbohydr. Res. 60 (1978) 315–326.
[EC 3.2.1.76 created 1972]
 
 
EC 3.2.1.77     
Accepted name: mannan 1,2-(1,3)-α-mannosidase
Reaction: Hydrolysis of (1→2)- and (1→3)-linkages in yeast mannan, releasing mannose
Other name(s): exo-1,2-1,3-α-mannosidase; 1,2-1,3-α-D-mannan mannohydrolase
Systematic name: (1→2)-(1→3)-α-D-mannan mannohydrolase
Comments: A 1,6-α-D-mannan backbone remains after action on yeast mannan. This is further attacked, but slowly.
References:
1.  Jones, G.H. and Ballou, C.E. Studies on the structure of yeast mannan. I. Purification and some properties of an α-mannosidase from an Arthrobacter species. J. Biol. Chem. 244 (1969) 1043–1051. [PMID: 5769177]
2.  Jones, G.H. and Ballou, C.E. Studies on the structure of yeast mannan. II. Mode of action of the Arthrobacter α-mannosidase on yeast mannan. J. Biol. Chem. 244 (1969) 1052–1059. [PMID: 5814027]
[EC 3.2.1.77 created 1972]
 
 
EC 3.2.1.78     
Accepted name: mannan endo-1,4-β-mannosidase
Reaction: Random hydrolysis of (1→4)-β-D-mannosidic linkages in mannans, galactomannans and glucomannans
Other name(s): endo-1,4-β-mannanase; endo-β-1,4-mannase; β-mannanase B; β-1,4-mannan 4-mannanohydrolase; endo-β-mannanase; β-D-mannanase; 1,4-β-D-mannan mannanohydrolase
Systematic name: 4-β-D-mannan mannanohydrolase
References:
1.  Eriksson, A.F.V. Purification and characterisation of a fungal β-mannanase. Acta Chem. Scand. 22 (1968) 1924–1934.
2.  Reese, E.T. β-Mannanases of fungi. Can. J. Microbiol. 11 (1965) 167–183. [PMID: 14323029]
[EC 3.2.1.78 created 1972]
 
 
EC 3.2.1.79      
Deleted entry:  α-L-arabinofuranoside hydrolase. Now included with EC 3.2.1.55 α-N-arabinofuranosidase
[EC 3.2.1.79 created 1972, deleted 1976]
 
 
EC 3.2.1.80     
Accepted name: fructan β-fructosidase
Reaction: Hydrolysis of terminal, non-reducing (2→1)- and (2→6)-linked β-D-fructofuranose residues in fructans
Other name(s): exo-β-D-fructosidase; exo-β-fructosidase; polysaccharide β-fructofuranosidase; fructan exohydrolase
Systematic name: β-D-fructan fructohydrolase
Comments: Hydrolyses inulin and levan, and also sucrose.
References:
1.  DaCosta, T. and Gibbons, R.J. Hydrolysis of levan by human plaque streptococci. Arch. Oral Biol. 13 (1968) 609–617. [PMID: 5244285]
2.  Jacques, N.J., Morrey-Jones, J.G. and Walker, G.J. Inducible and constitutive formation of fructanase in batch and continuous cultures of Streptococcus mutans. J. Gen. Microbiol. 131 (1985) 1625–1633. [PMID: 4045423]
[EC 3.2.1.80 created 1972]
 
 
EC 3.2.1.81     
Accepted name: β-agarase
Reaction: Hydrolysis of (1→4)-β-D-galactosidic linkages in agarose, giving the tetramer as the predominant product
Glossary: agarose = a linear polysaccharide produced by some members of the Rhodophyta (red algae) made up from alternating D-galactose and 3,6-anhydro-α-L-galactopyranose residues joined by α-(1→3)- and β-(1→4)-linkages. In the field of oligosaccharides derived from agarose, carrageenans, etc., in which alternate residues are 3,6-anhydro sugars, the prefix ’neo’ designates an oligosaccharide whose non-reducing end is the anhydro sugar, and the absence of this prefix means that it is not.
For example:
neoagarobiose = 3,6-anhydro-α-L-galactopyranosyl-(1→3)-D-galactose
agarobiose = β-D-galactopyranosyl-(1→4)-3,6-anhydro-L-galactose
Other name(s): agarase (ambiguous); AgaA; AgaB; endo-β-agarase; agarose 3-glycanohydrolase (incorrect)
Systematic name: agarose 4-glycanohydrolase
Comments: Also acts on porphyran, but more slowly [1]. This enzyme cleaves the β-(1→4) linkages of agarose in a random manner with retention of the anomeric-bond configuration, producing β-anomers that give rise progressively to α-anomers when mutarotation takes place [6]. The end products of hydrolysis are neoagarotetraose and neoagarohexaose in the case of AgaA from the marine bacterium Zobellia galactanivorans, and neoagarotetraose and neoagarobiose in the case of AgaB [6].
References:
1.  Duckworth, M. and Turvey, J.R. The action of a bacterial agarase on agarose, porphyran and alkali-treated porphyran. Biochem. J. 113 (1969) 687–692. [PMID: 5386190]
2.  Allouch, J., Jam, M., Helbert, W., Barbeyron, T., Kloareg, B., Henrissat, B. and Czjzek, M. The three-dimensional structures of two β-agarases. J. Biol. Chem. 278 (2003) 47171–47180. [PMID: 12970344]
3.  Ohta, Y., Nogi, Y., Miyazaki, M., Li, Z., Hatada, Y., Ito, S. and Horikoshi, K. Enzymatic properties and nucleotide and amino acid sequences of a thermostable β-agarase from the novel marine isolate, JAMB-A94. Biosci. Biotechnol. Biochem. 68 (2004) 1073–1081. [PMID: 15170112]
4.  Ohta, Y., Hatada, Y., Nogi, Y., Miyazaki, M., Li, Z., Akita, M., Hidaka, Y., Goda, S., Ito, S. and Horikoshi, K. Enzymatic properties and nucleotide and amino acid sequences of a thermostable β-agarase from a novel species of deep-sea Microbulbifer. Appl. Microbiol. Biotechnol. 64 (2004) 505–514. [PMID: 15088129]
5.  Sugano, Y., Terada, I., Arita, M., Noma, M. and Matsumoto, T. Purification and characterization of a new agarase from a marine bacterium, Vibrio sp. strain JT0107. Appl. Environ. Microbiol. 59 (1993) 1549–1554. [PMID: 8517750]
6.  Jam, M., Flament, D., Allouch, J., Potin, P., Thion, L., Kloareg, B., Czjzek, M., Helbert, W., Michel, G. and Barbeyron, T. The endo-β-agarases AgaA and AgaB from the marine bacterium Zobellia galactanivorans: two paralogue enzymes with different molecular organizations and catalytic behaviours. Biochem. J. 385 (2005) 703–713. [PMID: 15456406]
[EC 3.2.1.81 created 1972, modified 2006]
 
 
EC 3.2.1.82     
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.
References:
1.  Hasegawa, H. and Nagel, C.W. Isolation of an oligogalacturonate hydrolase from a Bacillus species. Arch. Biochem. Biophys. 124 (1968) 513–520. [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 3.2.1.83     
Accepted name: κ-carrageenase
Reaction: Endohydrolysis of (1→4)-β-D-linkages between D-galactose 4-sulfate and 3,6-anhydro-D-galactose in κ-carrageenans
Glossary: In the field of oligosaccharides derived from agarose, carrageenans, etc., in which alternate residues are 3,6-anhydro sugars, the prefix ’neo’ designates an oligosaccharide whose non-reducing end is the anhydro sugar, and the absence of this prefix means that it is not.
For example:
ι-neocarrabiose = 3,6-anhydro-2-O-sulfo-α-D-galactopyranosyl-(1→3)-4-O-sulfo-D-galactose
ι-carrabiose = 4-O-sulfo- β-D-galactopyranosyl-(1→4)-3,6-anhydro-2-O-sulfo-D-galactose
Other name(s): κ-carrageenan 4-β-D-glycanohydrolase
Systematic name: κ-carrageenan 4-β-D-glycanohydrolase (configuration-retaining)
Comments: The main products of hydrolysis are neocarrabiose-sulfate and neocarratetraose-sulfate [5]. Unlike EC 3.2.1.157 (ι-carrageenase), but similar to EC 3.2.1.81 (β-agarase), this enzyme proceeds with retention of the anomeric configuration.
References:
1.  Weigl, J. and Yashe, W. The enzymic hydrolysis of carrageenan by Pseudomonas carrageenovora: purification of a κ-carrageenase. Can. J. Microbiol. 12 (1966) 939–947. [PMID: 5972647]
2.  Potin, P., Sanseau, A., Le Gall, Y., Rochas, C. and Kloareg, B. Purification and characterization of a new κ-carrageenase from a marine Cytophaga-like bacterium. Eur. J. Biochem. 201 (1991) 241–247. [PMID: 1915370]
3.  Potin, P., Richard, C., Barbeyron, T., Henrissat, B., Gey, C., Petillot, Y., Forest, E., Dideberg, O., Rochas, C. and Kloareg, B. Processing and hydrolytic mechanism of the cgkA-encoded κ-carrageenase of Alteromonas carrageenovora. Eur. J. Biochem. 228 (1995) 971–975. [PMID: 7737202]
4.  Michel, G., Barbeyron, T., Flament, D., Vernet, T., Kloareg, B. and Dideberg, O. Expression, purification, crystallization and preliminary x-ray analysis of the κ-carrageenase from Pseudoalteromonas carrageenovora. Acta Crystallogr. D Biol. Crystallogr. 55 (1999) 918–920. [PMID: 10089334]
5.  Michel, G., Chantalat, L., Duee, E., Barbeyron, T., Henrissat, B., Kloareg, B. and Dideberg, O. The κ-carrageenase of P. carrageenovora features a tunnel-shaped active site: a novel insight in the evolution of Clan-B glycoside hydrolases. Structure 9 (2001) 513–525. [PMID: 11435116]
[EC 3.2.1.83 created 1972, modified 2006]
 
 
EC 3.2.1.84     
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.
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. [PMID: 4622000]
[EC 3.2.1.84 created 1972]
 
 
EC 3.2.1.85     
Accepted name: 6-phospho-β-galactosidase
Reaction: a 6-phospho-β-D-galactoside + H2O = 6-phospho-D-galactose + an alcohol
Other name(s): phospho-β-galactosidase; β-D-phosphogalactoside galactohydrolase; phospho-β-D-galactosidase; 6-phospho-β-D-galactosidase
Systematic name: 6-phospho-β-D-galactoside 6-phosphogalactohydrolase
References:
1.  Hengstenberg, W., Penberthy, W.K. and Morse, M.L. Purification of the staphylococcal 6-phospho-β-D-galactosidase. Eur. J. Biochem. 14 (1970) 27–32. [PMID: 5447434]
[EC 3.2.1.85 created 1976]
 
 
EC 3.2.1.86     
Accepted name: 6-phospho-β-glucosidase
Reaction: 6-phospho-β-D-glucosyl-(1→4)-D-glucose + H2O = D-glucose + D-glucose 6-phosphate
Other name(s): phospho-β-glucosidase A; phospho-β-glucosidase; phosphocellobiase; 6-phospho-β-D-glucosyl-(1,4)-D-glucose glucohydrolase
Systematic name: 6-phospho-β-D-glucosyl-(1→4)-D-glucose glucohydrolase
Comments: Also hydrolyses several other phospho-β-D-glucosides, but not their non-phosphorylated forms.
References:
1.  Palmer, R.E. and Anderson, R.L. Cellobiose metabolism in Aerobacter aerogenes. 3. Cleavage of cellobiose monophosphate by a phospho-β-glucosidase. J. Biol. Chem. 247 (1972) 3420–3423. [PMID: 4624114]
[EC 3.2.1.86 created 1976]
 
 
EC 3.2.1.87     
Accepted name: capsular-polysaccharide endo-1,3-α-galactosidase
Reaction: Random hydrolysis of (1→3)-α-D-galactosidic linkages in Aerobacter aerogenes capsular polysaccharide
Other name(s): polysaccharide depolymerase; capsular polysaccharide galactohydrolase
Systematic name: Aerobacter-capsular-polysaccharide galactohydrolase
Comments: Hydrolyses the galactosyl-α-1,3-D-galactose linkages only in the complex substrate, bringing about depolymerization.
References:
1.  Yurewicz, E.C., Ghalambor, M.A., Duckworth, D.H. and Heath, E.C. Catalytic and molecular properties of a phage-induced capsular polysaccharide depolymerase. J. Biol. Chem. 246 (1971) 5607–5716. [PMID: 5096084]
2.  Yurewicz, E.C., Ghalambor, M.A. and Heath, E.C. The structure of Aerobacter aerogenes capsular polysaccharide. J. Biol. Chem. 246 (1971) 5596–5606. [PMID: 4328830]
[EC 3.2.1.87 created 1976]
 
 
EC 3.2.1.88     
Accepted name: non-reducing end β-L-arabinopyranosidase
Reaction: Removal of a terminal β-L-arabinopyranose residue from the non-reducing end of its substrate.
Other name(s): vicianosidase; β-L-arabinosidase (ambiguous); β-L-arabinoside arabinohydrolase (ambiguous)
Systematic name: β-L-arabinopyranoside non-reducing end β-L-arabinopyranosidase
Comments: The enzyme, which was characterized from dormant seeds of the plant Cajanus cajan (pigeon pea), has been shown to remove the terminal non-reducing β-L-arabinopyranoside residue from the artificial substrate p-nitrophenyl-β-L-arabinopyranose [1]. In the presence of methanol the enzyme demonstrates transglycosylase activity, transferring the arabinose moiety to methanol while retaining the anomeric configuration, generating 1-O-methyl-β-L-arabinopyranose [2].
References:
1.  Dey, P.M. β-L-Arabinosidase from Cajanus indicus: a new enzyme. Biochim. Biophys. Acta 302 (1973) 393–398. [PMID: 4699248]
2.  Dey, P. M. Further characterization of β-L-arabinosidase from Cajanus indicus. Biochim.Biophys. Acta 746 (1983) 8–13.
[EC 3.2.1.88 created 1976, modified 2013]
 
 
EC 3.2.1.89     
Accepted name: arabinogalactan endo-β-1,4-galactanase
Reaction: The enzyme specifically hydrolyses (1→4)-β-D-galactosidic linkages in type I arabinogalactans.
Other name(s): endo-1,4-β-galactanase; galactanase (ambiguous); arabinogalactanase; ganB (gene name)
Systematic name: arabinogalactan 4-β-D-galactanohydrolase
Comments: This enzyme, isolated from the bacterium Bacillus subtilis, hydrolyses the β(1→4) bonds found in type I plant arabinogalactans, which are a component of the primary cell walls of dicots. The predominant product is a tetrasaccharide. cf. EC 3.2.1.181, galactan endo-β-1,3-galactanase.
References:
1.  Emi, S. and Yamamoto, T. Purification and properties of several galactanases of Bacillus subtilis var. amylosacchariticus. Agric. Biol. Chem. 36 (1972) 1945–1954.
2.  Labavitch, J.M., Freeman, L.E. and Albersheim, P. Structure of plant cell walls. Purification and characterization of a β-1,4-galactanase which degrades a structural component of the primary cell walls of dicots. J. Biol. Chem. 251 (1976) 5904–5910. [PMID: 823153]
3.  Shipkowski, S. and Brenchley, J.E. Bioinformatic, genetic, and biochemical evidence that some glycoside hydrolase family 42 β-galactosidases are arabinogalactan type I oligomer hydrolases. Appl. Environ. Microbiol. 72 (2006) 7730–7738. [PMID: 17056685]
[EC 3.2.1.89 created 1976, modified 2012]
 
 
EC 3.2.1.90      
Deleted entry:  arabinogalactan endo-1,3-β-galactosidase. The enzyme was not sufficiently characterized to warrant an EC number
[EC 3.2.1.90 created 1976, deleted 2001]
 
 
EC 3.2.1.91     
Accepted name: cellulose 1,4-β-cellobiosidase (non-reducing end)
Reaction: Hydrolysis of (1→4)-β-D-glucosidic linkages in cellulose and cellotetraose, releasing cellobiose from the non-reducing ends of the chains
Other name(s): exo-cellobiohydrolase; β-1,4-glucan cellobiohydrolase; β-1,4-glucan cellobiosylhydrolase; 1,4-β-glucan cellobiosidase; exoglucanase; avicelase; CBH 1; C1 cellulase; cellobiohydrolase I; cellobiohydrolase; exo-β-1,4-glucan cellobiohydrolase; 1,4-β-D-glucan cellobiohydrolase; cellobiosidase
Systematic name: 4-β-D-glucan cellobiohydrolase (non-reducing end)
References:
1.  Berghem, L.E.R. and Pettersson, L.G. The mechanism of enzymatic cellulose degradation. Purification of a cellulolytic enzyme from Trichoderma viride active on highly ordered cellulose. Eur. J. Biochem. 37 (1973) 21–30. [PMID: 4738092]
2.  Eriksson, K.E. and Pettersson, B. Extracellular enzyme system utilized by the fungus Sporotrichum pulverulentum (Chrysosporium lignorum) for the breakdown of cellulose. 3. Purification and physico-chemical characterization of an exo-1,4-β-glucanase. Eur. J. Biochem. 51 (1975) 213–218. [PMID: 235428]
3.  Halliwell, G., Griffin, M. and Vincent, R. The role of component C1 in cellulolytic systems. Biochem. J. 127 (1972) 43P. [PMID: 5076675]
[EC 3.2.1.91 created 1976, modified 2011]
 
 
EC 3.2.1.92     
Accepted name: peptidoglycan β-N-acetylmuramidase
Reaction: Hydrolysis of terminal, non-reducing N-acetylmuramic residues
Other name(s): exo-β-N-acetylmuramidase; exo-β-acetylmuramidase; β-2-acetamido-3-O-(D-1-carboxyethyl)-2-deoxy-D-glucoside acetamidodeoxyglucohydrolase
Systematic name: peptidoglycan β-N-acetylmuramoylexohydrolase
References:
1.  Del Rio, L.A. and Berkeley, R.C.W. Exo-β-N-acetylmuramidase - a novel hexosaminidase. Production by Bacillus subtilis B, purification and characterization. Eur. J. Biochem. 65 (1976) 3–12. [PMID: 6281]
[EC 3.2.1.92 created 1976]
 
 
EC 3.2.1.93     
Accepted name: α,α-phosphotrehalase
Reaction: α,α-trehalose 6-phosphate + H2O = D-glucose + D-glucose 6-phosphate
Other name(s): phosphotrehalase
Systematic name: α,α-trehalose-6-phosphate phosphoglucohydrolase
References:
1.  Bhumiratana, A., Anderson, R.L. and Costilow, R.N. Trehalose metabolism by Bacillus popilliae. J. Bacteriol. 119 (1974) 484–493. [PMID: 4369400]
[EC 3.2.1.93 created 1976]
 
 
EC 3.2.1.94     
Accepted name: glucan 1,6-α-isomaltosidase
Reaction: Hydrolysis of (1→6)-α-D-glucosidic linkages in polysaccharides, to remove successive isomaltose units from the non-reducing ends of the chains
Other name(s): exo-isomaltohydrolase; isomalto-dextranase; isomaltodextranase; G2-dextranase; 1,6-α-D-glucan isomaltohydrolase
Systematic name: 6-α-D-glucan isomaltohydrolase
Comments: Optimum activity is on those 1,6-α-D-glucans containing 6, 7 and 8 glucose units; those containing 3, 4 and 5 glucose units are hydrolysed at slower rates.
References:
1.  Sawai, T., Toriyama, K. and Yano, K. A bacterial dextranase releasing only isomaltose from dextrans. J. Biochem. (Tokyo) 75 (1974) 105–112. [PMID: 4826536]
2.  Sawai, T. and Niwa, Y. Transisomaltosylation activity of a bacterial isomaltodextranase. Agric. Biol. Chem. 39 (1975) 1077–1083.
[EC 3.2.1.94 created 1976]
 
 
EC 3.2.1.95     
Accepted name: dextran 1,6-α-isomaltotriosidase
Reaction: Hydrolysis of (1→6)-α-D-glucosidic linkages in dextrans, to remove successive isomaltotriose units from the non-reducing ends of the chains
Other name(s): exo-isomaltotriohydrolase; 1,6-α-D-glucan isomaltotriohydrolase
Systematic name: 6-α-D-glucan isomaltotriohydrolase
References:
1.  Sugiura, M., Ito, A. and Yamaguchi, T. Studies on dextranase. II. New exo-dextranase from Brevibacterium fuscum var. Dextranlyticum. Biochim. Biophys. Acta 350 (1974) 61–70. [PMID: 4210084]
[EC 3.2.1.95 created 1978]
 
 
EC 3.2.1.96     
Accepted name: mannosyl-glycoprotein endo-β-N-acetylglucosaminidase
Reaction: Endohydrolysis of the N,N′-diacetylchitobiosyl unit in high-mannose glycopeptides and glycoproteins containing the -[Man(GlcNAc)2]Asn- structure. One N-acetyl-D-glucosamine residue remains attached to the protein; the rest of the oligosaccharide is released intact
Other name(s): N,N′-diacetylchitobiosyl β-N-acetylglucosaminidase; endo-β-N-acetylglucosaminidase; mannosyl-glycoprotein endo-β-N-acetylglucosamidase; di-N-acetylchitobiosyl β-N-acetylglucosaminidase; endo-β-acetylglucosaminidase; endo-β-(1→4)-N-acetylglucosaminidase; mannosyl-glycoprotein 1,4-N-acetamidodeoxy-β-D-glycohydrolase; endoglycosidase S; endo-N-acetyl-β-D-glucosaminidase; endo-N-acetyl-β-glucosaminidase; endo-β-N-acetylglucosaminidase D; endo-β-N-acetylglucosaminidase F; endo-β-N-acetylglucosaminidase H; endo-β-N-acetylglucosaminidase L; glycopeptide-D-mannosyl-4-N-(N-acetyl-D-glucosaminyl)2-asparagine 1,4-N-acetyl-β-glucosaminohydrolase; endoglycosidase H
Systematic name: glycopeptide-D-mannosyl-N4-(N-acetyl-D-glucosaminyl)2-asparagine 1,4-N-acetyl-β-glucosaminohydrolase
Comments: A group of related enzymes.
References:
1.  Chien, S., Weinburg, R., Li, S. and Li, Y. Endo-β-N-acetylglucosaminidase from fig latex. Biochem. Biophys. Res. Commun. 76 (1977) 317–323.
2.  Koide, N. and Muramatsu, T. Endo-β-N-acetylglucosaminidase acting on carbohydrate moieties of glycoproteins. Purification and properties of the enzyme from Diplococcus pneumoniae. J. Biol. Chem. 249 (1974) 4897–4904. [PMID: 4152561]
3.  Pierce, R.J., Spik, G. and Montreuil, J. Cytosolic location of an endo-N-acetyl-β-D-glucosaminidase activity in rat liver and kidney. Biochem. J. 180 (1979) 673. [PMID: 486141]
4.  Pierce, R.J., Spik, G. and Montreuil, J. Demonstration and cytosolic location of an endo-N-acetyl-β-D-glucosaminidase activity towards an asialo-N-acetyl-lactosaminic-type substrate in rat liver. Biochem. J. 185 (1980) 261–264. [PMID: 7378051]
5.  Tai, T., Yamashita, K., Ogata-Arakawa, M., Koide, N., Muramatsu, T., Iwashita, S., Inoue, Y. and Kobata, A. Structural studies of two ovalbumin glycopeptides in relation to the endo-β-N-acetylglucosaminidase specificity. J. Biol. Chem. 250 (1975) 8569–8575. [PMID: 389]
6.  Tarentino, A.L., Plummer, T.H., Jr. and Maley, F. The release of intact oligosaccharides from specific glycoproteins by endo-β-N-acetylglucosaminidase H. J. Biol. Chem. 249 (1974) 818–824. [PMID: 4204553]
[EC 3.2.1.96 created 1978]
 
 
EC 3.2.1.97     
Accepted name: endo-α-N-acetylgalactosaminidase
Reaction: β-D-galactosyl-(1→3)-N-acetyl-α-D-galactosaminyl-[glycoprotein]-L-serine/L-threonine + H2O = β-D-galactosyl-(1→3)-N-acetyl-D-galactosamine + [glycoprotein]-L-serine/L-threonine
Other name(s): endo-α-acetylgalactosaminidase; endo-α-N-acetyl-D-galactosaminidase; mucinaminylserine mucinaminidase; D-galactosyl-3-(N-acetyl-α-D-galactosaminyl)-L-serine mucinaminohydrolase; endo-α-GalNAc-ase; glycopeptide α-N-acetylgalactosaminidase; D-galactosyl-N-acetyl-α-D-galactosamine D-galactosyl-N-acetyl-galactosaminohydrolase
Systematic name: glycopeptide-D-galactosyl-N-acetyl-α-D-galactosamine D-galactosyl-N-acetyl-galactosaminohydrolase
Comments: The enzyme catalyses the liberation of Gal-(1→3)-β-GalNAc α-linked to serine or threonine residues of mucin-type glycoproteins. EngBF from the bacterium Bifidobacterium longum specifically acts on core 1-type O-glycan to release the disaccharide Gal-(1→3)-β-GalNAc. The enzymes from the bacteria Clostridium perfringens, Enterococcus faecalis, Propionibacterium acnes and Alcaligenes faecalis show broader specificity (e.g. they can also release the core 2 trisaccharide Gal-(1→3)-β-(GlcNAc-(1→6)-β)-GalNAc or the core 3 disaccharide GlcNAc-(1→3)-β-GalNAc) [1,2]. The enzyme may play an important role in the degradation and utilization of mucins having core 1 O-glycan.
References:
1.  Ashida, H., Maki, R., Ozawa, H., Tani, Y., Kiyohara, M., Fujita, M., Imamura, A., Ishida, H., Kiso, M. and Yamamoto, K. Characterization of two different endo-α-N-acetylgalactosaminidases from probiotic and pathogenic enterobacteria, Bifidobacterium longum and Clostridium perfringens. Glycobiology 18 (2008) 727–734. [PMID: 18559962]
2.  Koutsioulis, D., Landry, D. and Guthrie, E.P. Novel endo-α-N-acetylgalactosaminidases with broader substrate specificity. Glycobiology 18 (2008) 799–805. [PMID: 18635885]
3.  Fujita, K., Oura, F., Nagamine, N., Katayama, T., Hiratake, J., Sakata, K., Kumagai, H. and Yamamoto, K. Identification and molecular cloning of a novel glycoside hydrolase family of core 1 type O-glycan-specific endo-α-N-acetylgalactosaminidase from Bifidobacterium longum. J. Biol. Chem. 280 (2005) 37415–37422. [PMID: 16141207]
4.  Suzuki, R., Katayama, T., Kitaoka, M., Kumagai, H., Wakagi, T., Shoun, H., Ashida, H., Yamamoto, K. and Fushinobu, S. Crystallographic and mutational analyses of substrate recognition of endo-α-N-acetylgalactosaminidase from Bifidobacterium longum. J. Biochem. 146 (2009) 389–398. [PMID: 19502354]
5.  Gregg, K.J. and Boraston, A.B. Cloning, recombinant production, crystallization and preliminary X-ray diffraction analysis of a family 101 glycoside hydrolase from Streptococcus pneumoniae. Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. 65 (2009) 133–135. [PMID: 19194003]
6.  Ashida, H., Yamamoto, K., Murata, T., Usui, T. and Kumagai, H. Characterization of endo-α-N-acetylgalactosaminidase from Bacillus sp. and syntheses of neo-oligosaccharides using its transglycosylation activity. Arch. Biochem. Biophys. 373 (2000) 394–400. [PMID: 10620364]
7.  Goda, H.M., Ushigusa, K., Ito, H., Okino, N., Narimatsu, H. and Ito, M. Molecular cloning, expression, and characterization of a novel endo-α-N-acetylgalactosaminidase from Enterococcus faecalis. Biochem. Biophys. Res. Commun. 375 (2008) 441–446. [PMID: 18725192]
[EC 3.2.1.97 created 1978 (EC 3.2.1.110 created 1984, incorporated 2008), modified 2008, modified 2011]
 
 
EC 3.2.1.98     
Accepted name: glucan 1,4-α-maltohexaosidase
Reaction: Hydrolysis of (1→4)-α-D-glucosidic linkages in amylaceous polysaccharides, to remove successive maltohexaose residues from the non-reducing chain ends
Other name(s): exo-maltohexaohydrolase; 1,4-α-D-glucan maltohexaohydrolase
Systematic name: 4-α-D-glucan maltohexaohydrolase
Comments: cf. EC 3.2.1.3 glucan 1,4-α-glucosidase, which removes successive glucose residues; EC 3.2.1.2 β-amylase, which removes successive maltose residues; EC 3.2.1.116 glucan 1,4-α-maltotriohydrolase, which removes successive maltotriose units and EC 3.2.1.60 glucan 1,4-α-maltotetraohydrolase, which removes successive maltotetraose residues. The products have the α-configuration.
References:
1.  Kainuma, K., Wako, K., Kobayashi, A., Nogami, A. and Suzuki, S. Purification and some properties of a novel maltohexaose-producing exo-amylase from Aerobacter aerogenes. Biochim. Biophys. Acta 410 (1975) 333–346. [PMID: 1094]
2.  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 3.2.1.98 created 1978]
 
 
EC 3.2.1.99     
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.
References:
1.  Kaji, A. and Saheki, T. Endo-arabinanase from Bacillus subtilis F-11. Biochim. Biophys. Acta 410 (1975) 354–360. [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. [PMID: 15556708]
[EC 3.2.1.99 created 1981, modified 2011]
 
 
EC 3.2.1.100     
Accepted name: mannan 1,4-mannobiosidase
Reaction: Hydrolysis of (1→4)-β-D-mannosidic linkages in (1→4)-β-D-mannans, to remove successive mannobiose residues from the non-reducing chain ends
Other name(s): 1,4-β-D-mannan mannobiohydrolase; exo-β-mannanase; exo-1,4-β-mannobiohydrolase
Systematic name: 4-β-D-mannan mannobiohydrolase
References:
1.  Araki, T. and Kitamikado, M. Purification and characterization of a novel exo-β-mannanase from Aeromonas sp. F-25. J. Biochem. (Tokyo) 91 (1982) 1181–1186. [PMID: 7096283]
[EC 3.2.1.100 created 1983]
 
 
EC 3.2.1.101     
Accepted name: mannan endo-1,6-α-mannosidase
Reaction: Random hydrolysis of (1→6)-α-D-mannosidic linkages in unbranched (1→6)-mannans
Other name(s): endo-α-1→6-D-mannanase; endo-1,6-β-mannanase; mannan endo-1,6-β-mannosidase; 1,6-α-D-mannan mannanohydrolase
Systematic name: 6-α-D-mannan mannanohydrolase
References:
1.  Nakajima, T., Maitra, S.K. and Ballou, C.E. An endo-α-1→6-D-mannanase from a soil bacterium. Purification, properties, and mode of action. J. Biol. Chem. 251 (1976) 174–181. [PMID: 811665]
2.  Brigance, W.T., Barlowe, C. and Graham, T.R. Organization of the yeast Golgi complex into at least four functionally distinct compartments. Mol. Biol. Cell 11 (2000) 171–182. [PMID: 10637300]
3.  Nakajima, T. and Ballou, C.E. Structure of the linkage region between the polysaccharide and protein parts of Saccharomyces cerevisiae mannan. J. Biol. Chem. 249 (1974) 7685–7694. [PMID: 4612041]
[EC 3.2.1.101 created 1984, modified 2001]
 
 
EC 3.2.1.102     
Accepted name: blood-group-substance endo-1,4-β-galactosidase
Reaction: Endohydrolysis of (1→4)-β-D-galactosidic linkages in blood group A and B substances
Other name(s): endo-β-galactosidase (ambiguous); blood-group-substance 1,4-β-D-galactanohydrolase
Systematic name: blood-group-substance 4-β-D-galactanohydrolase
Comments: Hydrolyses the 1,4-β-D-galactosyl linkages adjacent to a 1,3-α-D-galactosyl or N-acetylgalactosaminyl residues and a 1,2-α-D-fucosyl residue.
References:
1.  Fukuda, M.N. and Matsumara, G. Endo-β-galactosidase of Escherichia freundii. Purification and endoglycosidic action on keratan sulfates, oligosaccharides, and blood group active glycoprotein. J. Biol. Chem. 251 (1976) 6218–6225. [PMID: 135762]
2.  Nakazawa, K. and Suzuki, S. Purification of keratan sulfate-endogalactosidase and its action on keratan sulfates of different origin. J. Biol. Chem. 250 (1975) 912–917. [PMID: 234443]
3.  Takasaki, S. and Kobata, A. Purification and characterization of an endo-β-galactosidase produced by Diplococcus pneumoniae. J. Biol. Chem. 251 (1976) 3603–3609. [PMID: 6459]
[EC 3.2.1.102 created 1984]
 
 
EC 3.2.1.103     
Accepted name: keratan-sulfate endo-1,4-β-galactosidase
Reaction: Endohydrolysis of (1→4)-β-D-galactosidic linkages in keratan sulfate
Other name(s): endo-β-galactosidase (ambiguous); keratan sulfate endogalactosidase; keratanase; keratan-sulfate 1,4-β-D-galactanohydrolase
Systematic name: keratan-sulfate 4-β-D-galactanohydrolase
Comments: Hydrolyses the 1,4-β-D-galactosyl linkages adjacent to 1,3-N-acetyl-α-D-glucosaminyl residues. Also acts on some non-sulfated oligosaccharides, but only acts on blood group substances when the 1,2-linked fucosyl residues have been removed (cf. EC 3.2.1.102 blood-group-substance endo-1,4-β-galactosidase).
References:
1.  Fukuda, M.N. and Matsumara, G. Endo-β-galactosidase of Escherichia freundii. Purification and endoglycosidic action on keratan sulfates, oligosaccharides, and blood group active glycoprotein. J. Biol. Chem. 251 (1976) 6218–6225. [PMID: 135762]
[EC 3.2.1.103 created 1984]
 
 
EC 3.2.1.104     
Accepted name: steryl-β-glucosidase
Reaction: cholesteryl-β-D-glucoside + H2O = D-glucose + cholesterol
Systematic name: cholesteryl-β-D-glucoside glucohydrolase
Comments: Acts on glucosides of cholesterol and sitosterol, but not on some related sterols such as coprostanol.
References:
1.  Kalinowska, M. and Wojciechowski, Z.A. Purification and some properties of steryl β-D-glucoside hydrolase from Sinapis alba seedlings. Phytochemistry 17 (1978) 1533–1537.
[EC 3.2.1.104 created 1984]
 
 
EC 3.2.1.105     
Accepted name: 3α(S)-strictosidine β-glucosidase
Reaction: strictosidine + H2O = D-glucose + strictosidine aglycone
Systematic name: strictosidine β-D-glucohydrolase
Comments: Does not act on a number of closely related glycosides. Strictosidine is a precursor of indole alkaloids.
References:
1.  Hemscheidt, T. and Zenk, M.H. Glucosidases involved in indole alkaloid biosynthesis of Catharanthus cell cultures. FEBS Lett. 110 (1980) 187–191. [PMID: 6768587]
2.  Barleben, L., Ma, X., Koepke, J., Peng, G., Michel, H. and Stöckigt, J. Expression, purification, crystallization and preliminary X-ray analysis of strictosidine glucosidase, an enzyme initiating biosynthetic pathways to a unique diversity of indole alkaloid skeletons. Biochim. Biophys. Acta 1747 (2005) 89–92. [PMID: 15680242]
[EC 3.2.1.105 created 1984]
 
 
EC 3.2.1.106     
Accepted name: mannosyl-oligosaccharide glucosidase
Reaction: Glc3Man9GlcNAc2-[protein] + H2O = Glc2Man9GlcNAc2-[protein] + β-D-glucopyranose
Glossary: Glc3Man9GlcNAc2 = [α-D-Glc-(1→2)-α-D-Glc-(1→3)-α-D-Glc-(1→3)-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→2)-α-D-Man-(1→6)]-α-D-Man-(1→6)}-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc]-N-Asn-[protein]
Glc2Man9GlcNAc2-[protein] = [α-D-Glc-(1→3)-α-D-Glc-(1→3)-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→2)-α-D-Man-(1→6)]-α-D-Man-(1→6)}-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc]-N-Asn-[protein]
Other name(s): Glc3Man9NAc2 oligosaccharide glucosidase; trimming glucosidase I; CWH41 (gene name); MOGS (gene name); mannosyl-oligosaccharide glucohydrolase
Systematic name: Glc3Man9GlcNAc2-[protein] glucohydrolase (configuration-inverting)
Comments: This enzyme catalyses the first step in the processing of the N-glycan tetradecasaccharide precursor Glc3Man9GlcNAc2, which takes place in the endoplasmic reticulum, by removing the distal α-1,2-linked glucose residue. This and subsequent processing steps are required before complex N-glycans can be synthesized.
References:
1.  Elting, J.J., Chen, W.W. and Lennarz, J. Characterization of a glucosidase involved in an initial step in the processing of oligosaccharide chains. J. Biol. Chem. 255 (1980) 2325–2331. [PMID: 7358674]
2.  Grinna, L.S. and Robbins, P.W. Glycoprotein biosynthesis. Rat liver microsomal glucosidases which process oligosaccharides. J. Biol. Chem. 254 (1979) 8814–8818. [PMID: 479161]
3.  Kilker, R.D., Saunier, B., Tkacz, J.S. and Herscovics, A. Partial purification from Saccharomyces cerevisiae of a soluble glucosidase which removes the terminal glucose from the oligosaccharide Glc3Man9GlcNAc2. J. Biol. Chem. 256 (1981) 5299–5603. [PMID: 7014569]
4.  Grinna, L.S. and Robbins, P.W. Substrate specificities of rat liver microsomal glucosidases which process glycoproteins. J. Biol. Chem. 255 (1980) 2255–2258. [PMID: 7358666]
5.  Mark, M.J. and Kornfeld, S. Partial purification and characterization of the glucosidases involved in the processing of asparagine-linked oligosaccharides. Arch. Biochem. Biophys. 199 (1980) 249–258. [PMID: 7356331]
[EC 3.2.1.106 created 1984, modified 2018]
 
 
EC 3.2.1.107     
Accepted name: protein-glucosylgalactosylhydroxylysine glucosidase
Reaction: [collagen]-(5R)-5-O-[α-D-glucosyl-(1→2)-β-D-galactosyl]-5-hydroxy-L-lysine + H2O = D-glucose + [collagen]-(5R)-5-O-(β-D-galactosyl)-5-hydroxy-L-lysine
Other name(s): PGGHG (gene name); 2-O-α-D-glucopyranosyl-5-O-α-D-galactopyranosylhydroxy-L-lysine glucohydrolase; protein-α-D-glucosyl-1,2-β-D-galactosyl-L-hydroxylysine glucohydrolase; protein-α-D-glucosyl-(1→2)-β-D-galactosyl-L-hydroxylysine glucohydrolase
Systematic name: [collagen]-(5R)-5-O-[α-D-glucosyl-(1→2)-β-D-galactosyl]-5-hydroxy-L-lysine glucohydrolase
Comments: The enzyme specifically hydrolyses glucose from α-D-glucosyl-(1→2)-β-D-galactosyl disaccharide units that are linked to hydroxylysine residues of collagen and collagen-like proteins. Acetylation of the ε-amino group of the glycosylated hydroxylysine abolishes activity.
References:
1.  Hamazaki, H. and Hotta, K. Purification and characterization of an α-glucosidase specific for hydroxylysine-linked disaccharide of collagen. J. Biol. Chem. 254 (1979) 9682–9687. [PMID: 385589]
2.  Hamazaki, H. and Hotta, K. Enzymatic hydrolysis of disaccharide unit of collagen. Isolation of 2-O-α-D-glucopyranosyl-O-β-D-galactopyranosyl-hydroxylysine glucohydrolase from rat spleens. Eur. J. Biochem. 111 (1980) 587–591. [PMID: 7460918]
3.  Sternberg, M. and Shapiro, R.G. Studies on the catabolism of the hydroxylysine-linked disaccharide units of basement membranes and collagens. Isolation and characterization of a rat kidney α-glucosidase of high specificity. J. Biol. Chem. 254 (1979) 10329–10336. [PMID: 385599]
4.  Hamazaki, H. and Hamazaki, M.H. Catalytic site of human protein-glucosylgalactosylhydroxylysine glucosidase: Three crucial carboxyl residues were determined by cloning and site-directed mutagenesis. Biochem. Biophys. Res. Commun. 469 (2016) 357–362. [PMID: 26682924]
[EC 3.2.1.107 created 1984]
 
 
EC 3.2.1.108     
Accepted name: lactase
Reaction: lactose + H2O = D-galactose + D-glucose
Glossary: lactose = β-D-galactopyranosyl-(1→4)-α-D-glucopyranose
Other name(s): lactase-phlorizin hydrolase
Systematic name: lactose galactohydrolase
Comments: The enzyme from intestinal mucosa is isolated as a complex that also catalyses the reaction of EC 3.2.1.62 glycosylceramidase. cf. EC 3.2.1.33 amylo-α-1,6-glucosidase.
References:
1.  Lorenz-Meyer, H., Blum, A.L., Haemmerli, H.P. and Semenza, G. A second enzyme defect in acquired lactase deficiency: lack of small-intestinal phlorizin-hydrolase. Eur. J. Clin. Invest. 2 (1972) 326–331. [PMID: 5082068]
2.  Ramaswamay, S. and Radhakrishnan, A.N. Lactase-phlorizin hydrolase complex from monkey small intestine. Purification, properties and evidence for two catalytic sites. Biochim. Biophys. Acta 403 (1975) 446–455. [PMID: 810166]
3.  Schlegel-Haueter, S., Hore, P., Kerry, K.R. and Semenza, G. The preparation of lactase and glucoamylase of rat small intestine. Biochim. Biophys. Acta 258 (1972) 506–519. [PMID: 5010299]
4.  Skovbjerg, H., Norén, O., Sjöström, H., Danielsen, E.M. and Enevoldsen, B.S. Further characterization of intestinal lactase/phlorizin hydrolase. Biochim. Biophys. Acta 707 (1982) 89–97. [PMID: 6814489]
5.  Skovbjerg, H., Sjöström, H. and Norén, O. Purification and characterization of amphiphilic lactase-phlorizin hydrolase from human small-intestine. Eur. J. Biochem. 114 (1981) 653–661. [PMID: 6786877]
6.  Asp, N.G., Dahlqvist, A. and Koldovský, O. Human small-intestinal β-galactosidases. Separation and characterization of one lactase and one hetero β-galactosidase. Biochem. J. 114 (1969) 351–359. [PMID: 5822067]
[EC 3.2.1.108 created 1984]
 
 
EC 3.2.1.109     
Accepted name: endogalactosaminidase
Reaction: Endohydrolysis of (1→4)-α-D-galactosaminidic linkages in poly(D-galactosamine)
Systematic name: galactosaminoglycan glycanohydrolase
References:
1.  Reissig, J.L., Lau, W. and Glasgow, J.E. An endogalactosaminidase from Streptomyces griseus. Can. J. Biochem. 53 (1975) 1237–1249. [PMID: 3271]
2.  Tamura, J., Takagi, H. and Kadowaki, K. Purification and some properties of the endo α-1,4-polygalactosaminidase from Pseudomonas sp. Agric. Biol. Chem. 52 (1988) 2475–2484.
[EC 3.2.1.109 created 1984]
 
 
EC 3.2.1.110      
Deleted entry: mucinaminylserine mucinaminidase. The enzyme is identical to EC 3.2.1.97, glycopeptide α-N-acetylgalactosaminidase
[EC 3.2.1.110 created 1984, deleted 2008]
 
 
EC 3.2.1.111     
Accepted name: 1,3-α-L-fucosidase
Reaction: Hydrolysis of (1→3)-linkages between α-L-fucose and N-acetylglucosamine residues in glycoproteins
Other name(s): almond emulsin fucosidase I
Systematic name: 3-α-L-fucosyl-N-acetylglucosaminyl-glycoprotein fucohydrolase
Comments: Not identical with EC 3.2.1.63 1,2-α-L-fucosidase.
References:
1.  Imber, M.J., Glasgow, L.R. and Pizzo, S.V. Purification of an almond emulsin fucosidase on Cibacron blue-sepharose and demonstration of its activity toward fucose-containing glycoproteins. J. Biol. Chem. 257 (1982) 8205–8210. [PMID: 7085666]
2.  Ogata-Arakawa, M., Muramatsu, T. and Kobata, A. α-L-Fucosidases from almond emulsin: characterization of the two enzymes with different specificities. Arch. Biochem. Biophys. 181 (1977) 353–358. [PMID: 18111]
3.  Yoshima, H., Takasaki, S., Ito-Mega, S. and Kobata, A. Purification of almond emulsin α-L-fucosidase I by affinity chromatography. Arch. Biochem. Biophys. 194 (1979) 394–398. [PMID: 443810]
[EC 3.2.1.111 created 1986]
 
 
EC 3.2.1.112     
Accepted name: 2-deoxyglucosidase
Reaction: a 2-deoxy-α-D-glucoside + H2O = 2-deoxy-D-glucose + an alcohol
Other name(s): 2-deoxy-α-glucosidase; 2-deoxy-α-D-glucosidase
Systematic name: 2-deoxy-α-D-glucoside deoxyglucohydrolase
References:
1.  Canellakis, Z.N., Bondy, P.K., May, J.A., Jr., Myers-Robfogel, M.K. and Sartorelli, A.C. Identification of a glycosidase activity with apparent specificity for 2-deoxy-D-glucose in glycosidic linkage. Eur. J. Biochem. 143 (1984) 159–163. [PMID: 6468386]
[EC 3.2.1.112 created 1986]
 
 
EC 3.2.1.113     
Accepted name: mannosyl-oligosaccharide 1,2-α-mannosidase
Reaction: (1) Man9GlcNAc2-[protein] + 4 H2O = Man5GlcNAc2-[protein] + 4 β-D-mannopyranose (overall reaction)
(1a) Man9GlcNAc2-[protein] + H2O = Man8GlcNAc2-[protein] (isomer 8A1,2,3B1,2) + β-D-mannopyranose
(1b) Man8GlcNAc2-[protein] (isomer 8A1,2,3B1,2) + H2O = Man7GlcNAc2-[protein] (isomer 7A1,2,3B2) + β-D-mannopyranose
(1c) Man7GlcNAc2-[protein] (isomer 7A1,2,3B2) + H2O = Man6GlcNAc2-[protein] (isomer 6A1,2B2) + β-D-mannopyranose
(1d) Man6GlcNAc2-[protein] (isomer 6A1,2B2) + H2O = Man5GlcNAc2-[protein] + β-D-mannopyranose
(2) Man8GlcNAc2-[protein] (isomer 8A1,2,3B1,3) + 3 H2O = Man5GlcNAc2-[protein] + 3 β-D-mannopyranose (overall reaction)
(2a) Man8GlcNAc2-[protein] (isomer 8A1,2,3B1,3) + H2O = Man7GlcNAc2-[protein] (isomer 7A1,2,3B1) + β-D-mannopyranose
(2b) Man7GlcNAc2-[protein] (isomer 7A1,2,3B1) + H2O = Man6GlcNAc2-[protein] (isomer 6A1,2,3) + β-D-mannopyranose
(2c) Man6GlcNAc2-[protein] (isomer 6A1,2,3) + H2O = Man5GlcNAc2-[protein] + β-D-mannopyranose
Glossary: Man9GlcNAc2-[protein] = [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→2)-α-D-Man-(1→6)]-α-D-Man-(1→6)}-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc]-N-Asn-[protein]
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)-β-D-GlcNAc]-N-Asn-[protein]
Man5GlcNAc2-[protein] = [α-D-Man-(1→3)-{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)-β-D-GlcNAc]-N-Asn-[protein]
Other name(s): mannosidase 1A; mannosidase 1B; 1,2-α-mannosidase; exo-α-1,2-mannanase; mannose-9 processing α-mannosidase; glycoprotein processing mannosidase I; mannosidase I; Man9-mannosidase; ManI; 1,2-α-mannosyl-oligosaccharide α-D-mannohydrolase; MAN1A1 (gene name); MAN1A2 (gene name); MAN1C1 (gene name); 2-α-mannosyl-oligosaccharide α-D-mannohydrolase
Systematic name: Man9GlcNAc2-[protein] α-2-mannohydrolase (configuration-inverting)
Comments: This family of mammalian enzymes, located in the Golgi system, participates in the maturation process of N-glycans that leads to formation of hybrid and complex structures. The enzymes catalyse the hydrolysis of the four (1→2)-linked α-D-mannose residues from the Man9GlcNAc2 oligosaccharide attached to target proteins as described in reaction (1). Alternatively, the enzymes act on the Man8GlcNAc2 isomer formed by EC 3.2.1.209, endoplasmic reticulum Man9GlcNAc2 1,2-α-mannosidase, as described in reaction (2). The enzymes are type II membrane proteins, require Ca2+, and use an inverting mechanism. While all three human enzymes can catalyse the reactions listed here, some of the enzymes can additionally catalyse hydrolysis in an alternative order, generating additional isomeric intermediates, although the final product is the same. The names of the isomers listed here are based on a nomenclature system proposed by Prien et al [7].
References:
1.  Tabas, I. and Kornfeld, S. Purification and characterization of a rat liver Golgi α-mannosidase capable of processing asparagine-linked oligosaccharides. J. Biol. Chem. 254 (1979) 11655–11663. [PMID: 500665]
2.  Tulsiani, D.R.P., Hubbard, S.C., Robbins, P.W. and Touster, O. α-D-Mannosidases of rat liver Golgi membranes. Mannosidase II is the GlcNAcMAN5-cleaving enzyme in glycoprotein biosynthesis and mannosidases IA and IB are the enzymes converting Man9 precursors to Man5 intermediates. J. Biol. Chem. 257 (1982) 3660–3668. [PMID: 7061502]
3.  Bieberich, E. and Bause, E. Man9-mannosidase from human kidney is expressed in COS cells as a Golgi-resident type II transmembrane N-glycoprotein. Eur. J. Biochem. 233 (1995) 644–649. [PMID: 7588811]
4.  Tremblay, L.O., Campbell Dyke, N. and Herscovics, A. Molecular cloning, chromosomal mapping and tissue-specific expression of a novel human α1,2-mannosidase gene involved in N-glycan maturation. Glycobiology 8 (1998) 585–595. [PMID: 9592125]
5.  Lal, A., Pang, P., Kalelkar, S., Romero, P.A., Herscovics, A. and Moremen, K.W. Substrate specificities of recombinant murine Golgi α1,2-mannosidases IA and IB and comparison with endoplasmic reticulum and Golgi processing α1,2-mannosidases. Glycobiology 8 (1998) 981–995. [PMID: 9719679]
6.  Tremblay, L.O. and Herscovics, A. Characterization of a cDNA encoding a novel human Golgi α 1, 2-mannosidase (IC) involved in N-glycan biosynthesis. J. Biol. Chem. 275 (2000) 31655–31660. [PMID: 10915796]
7.  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. [PMID: 19181540]
[EC 3.2.1.113 created 1986, modified 2019]
 
 
EC 3.2.1.114     
Accepted name: mannosyl-oligosaccharide 1,3-1,6-α-mannosidase
Reaction: Man5GlcNAc3-[protein] + 2 H2O = Man3GlcNAc3-[protein] + 2 α-D-mannopyranose
Glossary: Man5GlcNAc3-[protein] = [β-D-GlcNAc-(1→2)-α-D-Man-(1→3)-{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)-β-D-GlcNAc]-N-Asn-[protein]
Man3GlcNAc3-[protein] = {β-D-GlcNAc-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc}-N-Asn-[protein]
Other name(s): MAN2A1 (gene name); MAN2A2 (gene name); mannosidase II; exo-1,3-1,6-α-mannosidase; α-D-mannosidase II; α-mannosidase II; α1-3,6-mannosidase; GlcNAc transferase I-dependent α1,3[α1,6]mannosidase; Golgi α-mannosidase II; ManII; 1,3(1,6)-α-D-mannosidase; 1,3-(1,6-)mannosyl-oligosaccharide α-D-mannohydrolase; (1→3)-(1→6)-mannosyl-oligosaccharide α-D-mannohydrolase
Systematic name: (1→3)-(1→6)-mannosyl-oligosaccharide α-D-mannohydrolase (configuration-retaining)
Comments: The enzyme, found in plants and animals, participates in the processing of N-glycans in the Golgi apparatus. It removes two mannosyl residues, one linked by α1,3 linkage, and the other linked by α1,6 linkage, both of which are removed by the same catalytic site. The enzyme is sensitive to swainsonine.
References:
1.  Tulsiani, D.R.P., Opheim, D.J. and Touster, O. Purification and characterization of α-D-mannosidase from rat liver golgi membranes. J. Biol. Chem. 252 (1977) 3227–3233. [PMID: 863880]
2.  Tabas, I. and Kornfeld, S. The synthesis of complex-type oligosaccharides. III. Identification of an α-D-mannosidase activity involved in a late stage of processing of complex-type oligosaccharides. J. Biol. Chem. 253 (1978) 7779–7786. [PMID: 212436]
3.  Harpaz, N. and Schachter, H. Control of glycoprotein synthesis. Processing of asparagine-linked oligosaccharides by one or more rat liver Golgi α-D-mannosidases dependent on the prior action of UDP-N-acetylglucosamine: α-D-mannoside β2-N-acetylglucosaminyltransferase I. J. Biol. Chem. 255 (1980) 4894–4902. [PMID: 6445359]
4.  Tulsiani, D.R.P., Hubbard, S.C., Robbins, P.W. and Touster, O. α-D-Mannosidases of rat liver Golgi membranes. Mannosidase II is the GlcNAcMAN5-cleaving enzyme in glycoprotein biosynthesis and mannosidases IA and IB are the enzymes converting Man9 precursors to Man5 intermediates. J. Biol. Chem. 257 (1982) 3660–3668. [PMID: 7061502]
5.  Moremen, K.W. and Robbins, P.W. Isolation, characterization, and expression of cDNAs encoding murine α-mannosidase II, a Golgi enzyme that controls conversion of high mannose to complex N-glycans. J. Cell Biol. 115 (1991) 1521–1534. [PMID: 1757461]
6.  Misago, M., Liao, Y.F., Kudo, S., Eto, S., Mattei, M.G., Moremen, K.W. and Fukuda, M.N. Molecular cloning and expression of cDNAs encoding human α-mannosidase II and a previously unrecognized α-mannosidase IIx isozyme. Proc. Natl. Acad. Sci. USA 92 (1995) 11766–11770. [PMID: 8524845]
7.  van den Elsen, J.M., Kuntz, D.A. and Rose, D.R. Structure of Golgi α-mannosidase II: a target for inhibition of growth and metastasis of cancer cells. EMBO J. 20 (2001) 3008–3017. [PMID: 11406577]
8.  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. [PMID: 15721331]
9.  Shah, N., Kuntz, D.A. and Rose, D.R. Golgi α-mannosidase II cleaves two sugars sequentially in the same catalytic site. Proc. Natl. Acad. Sci. USA 105 (2008) 9570–9575. [PMID: 18599462]
10.  Rose, D.R. Structure, mechanism and inhibition of Golgi α-mannosidase II. Curr. Opin. Struct. Biol. 22 (2012) 558–562. [PMID: 22819743]
[EC 3.2.1.114 created 1986, modified 2018]
 
 
EC 3.2.1.115     
Accepted name: branched-dextran exo-1,2-α-glucosidase
Reaction: Hydrolysis of (1→2)-α-D-glucosidic linkages at the branch points of dextrans and related polysaccharides, producing free D-glucose
Other name(s): dextran 1,2-α-glucosidase; dextran α-1,2 debranching enzymel 1,2-α-D-glucosyl-branched-dextran 2-glucohydrolase
Systematic name: (1→2)-α-D-glucosyl-branched-dextran 2-glucohydrolase
Comments: Does not hydrolyse disaccharides or oligosaccharides containing linear 1,2-α-glucosidic linkages.
References:
1.  Mitsuishi, Y., Kobayashi, M. and Matsuda, K. Dextran α-1,2-debranching enzyme from Flavobacterium sp. M-73: its production and purification. Agric. Biol. Chem. 43 (1979) 2283–2290.
2.  Mitsuishi, Y., Kobayashi, M. and Matsuda, K. Dextran α-(1→2)-debranching enzyme from Flavobacterium sp. M-73. Properties and mode of action. Carbohydr. Res. 83 (1980) 303–313. [PMID: 7407800]
[EC 3.2.1.115 created 1989]
 
 
EC 3.2.1.116     
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.
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 3.2.1.117     
Accepted name: amygdalin β-glucosidase
Reaction: (R)-amygdalin + H2O = (R)-prunasin + D-glucose
Other name(s): amygdalase; amygdalinase; amygdalin hydrolase; amygdalin glucosidase
Systematic name: amygdalin β-D-glucohydrolase
Comments: Highly specific; does not act on prunasin, linamarin, gentiobiose or cellobiose (cf. EC 3.2.1.21 β-glucosidase).
References:
1.  Kuroki, G., Lizotte, P.A. and Poulton, J.E. L-β-Glycosidases from Prunus serotina EHRH and Davallia trichomanoides. Z. Natursforsch. C: Biosci. 39 (1984) 232–239.
[EC 3.2.1.117 created 1989]
 
 
EC 3.2.1.118     
Accepted name: prunasin β-glucosidase
Reaction: (R)-prunasin + H2O = D-glucose + mandelonitrile
Other name(s): prunasin hydrolase
Systematic name: prunasin β-D-glucohydrolase
Comments: Highly specific; does not act on amygdalin, linamarin or gentiobiose. (cf. EC 3.2.1.21 β-glucosidase).
References:
1.  Kuroki, G., Lizotte, P.A. and Poulton, J.E. L-β-Glycosidases from Prunus serotina EHRH and Davallia trichomanoides. Z. Natursforsch. C: Biosci. 39 (1984) 232–239.
[EC 3.2.1.118 created 1989]
 
 
EC 3.2.1.119     
Accepted name: vicianin β-glucosidase
Reaction: (R)-vicianin + H2O = mandelonitrile + vicianose
Other name(s): vicianin hydrolase
Systematic name: (R)-vicianin β-D-glucohydrolase
Comments: Also hydrolyses, more slowly, (R)-amygdalin and (R)-prunasin, but not gentiobiose, linamarin or cellobiose.
References:
1.  Kuroki, G., Lizotte, P.A. and Poulton, J.E. L-β-Glycosidases from Prunus serotina EHRH and Davallia trichomanoides. Z. Natursforsch. C: Biosci. 39 (1984) 232–239.
[EC 3.2.1.119 created 1989]
 
 
EC 3.2.1.120     
Accepted name: oligoxyloglucan β-glycosidase
Reaction: Hydrolysis of (1→4)-β-D-glucosidic links in oligoxyloglucans so as to remove successive isoprimeverose [i.e. α-xylo-(1→6)-β-D-glucosyl-] residues from the non-reducing chain ends
Other name(s): isoprimeverose-producing oligoxyloglucan hydrolase; oligoxyloglucan hydrolase
Systematic name: oligoxyloglucan xyloglucohydrolase
References:
1.  Kato, Y., Matsushita, J., Kubodera, T. and Matsuda, K. A novel enzyme producing isoprimeverose from oligoxyloglucans of Aspergillus oryzae. J. Biochem. (Tokyo) 97 (1985) 801–810. [PMID: 4019436]
[EC 3.2.1.120 created 1989]
 
 
EC 3.2.1.121     
Accepted name: polymannuronate hydrolase
Reaction: Endohydrolysis of the D-mannuronide linkages of polymannuronate
Other name(s): polymannuronic acid polymerase
Systematic name: poly(mannuronide) mannuronohydrolase
Comments: Does not act on alginic acid, which is a copolymer of polymannuronate.
References:
1.  Dunne, W.M., Jr. and Buckmire, F.L.A. Partial purification and characterization of a polymannuronic acid depolymerase produced by a mucoid strain of Pseudomonas aeruginosa isolated from a patient with cystic fibrosis. Appl. Environ. Microbiol. 50 (1985) 562–567. [PMID: 3935048]
[EC 3.2.1.121 created 1989]
 
 
EC 3.2.1.122     
Accepted name: maltose-6′-phosphate glucosidase
Reaction: α-maltose 6′-phosphate + H2O = D-glucose + D-glucose 6-phosphate
Other name(s): phospho-α-glucosidase; maltose-6′-phosphate 6-phosphoglucohydrolase
Systematic name: α-maltose-6′-phosphate 6-phosphoglucohydrolase
Comments: Hydrolyses a variety of 6-phospho-α-D-glucosides, including α-maltose 6′-phosphate, α,α-trehalose 6-phosphate, sucrose 6-phosphate and p-nitrophenyl-α-D-glucopyranoside 6-phosphate (as a chromogenic substrate). The enzyme is activated by FeII, MnII, CoII and NiII. It is rapidly inactivated in air.
References:
1.  Thompson, J., Gentry-Weeks, C.R., Nguyen, N.Y., Folk, J.E., Robrish, S.A. Purification from Fusobacterium mortiferum ATCC 25557 of a 6-phosphoryl-O-α-D-glucopyranosyl:6-phosphoglucohydrolase that hydrolyses maltose 6-phosphate and related phospho-α-D-glucosides. J. Bacteriol. 177 (1995) 2505–2512. [PMID: 7730284]
[EC 3.2.1.122 created 1989, modified 1999]
 
 
EC 3.2.1.123     
Accepted name: endoglycosylceramidase
Reaction: oligoglycosylglucosyl-(1↔1)-ceramide + H2O = ceramide + oligoglycosylglucose
Other name(s): endoglycoceramidase; EGCase; glycosyl-N-acetyl-sphingosine 1,1-β-D-glucanohydrolase; oligoglycosylglucosylceramide glycohydrolase; oligoglycosylglucosyl(1↔1)ceramide glycohydrolase
Systematic name: oligoglycosylglucosyl-(1↔1)-ceramide glycohydrolase
Comments: An enzyme from Rhodococcus sp. that degrades various acidic and neutral glycosphingolipids to oligosaccharides and ceramides, by cleaving a glucosyl bond. Does not act on monoglycosylceramides. cf. EC 3.2.1.62 glycosylceramidase.
References:
1.  Ito, M. and Yamagata, T. A novel glycosphingolipid-degrading enzyme cleaves the linkage between the oligosaccharide and ceramide of neutral and acidic glycosphingolipids. J. Biol. Chem. 261 (1986) 14278–14282. [PMID: 3771534]
[EC 3.2.1.123 created 1989]
 
 
EC 3.2.1.124     
Accepted name: 3-deoxy-2-octulosonidase
Reaction: Endohydrolysis of the β-ketopyranosidic linkages of 3-deoxy-D-manno-2-octulosonate in capsular polysaccharides
Other name(s): 2-keto-3-deoxyoctonate hydrolase; octulosylono hydrolase; octulofuranosylono hydrolase; octulopyranosylonohydrolase
Systematic name: capsular-polysaccharide 3-deoxy-D-manno-2-octulosonohydrolase
Comments: The enzyme from a bacteriophage catalyses the depolymerization of capsular polysaccharides containing 3-deoxy-2-octulosonide in the cell wall of Escherichia coli.
References:
1.  Altmann, F., Kwiatkowski, B., Stirm, S., März, L. and Unger, F.M. A bacteriophage-associated glycanase cleaving β-pyranosidic linkages of 3-deoxy-D-manno-2-octulosonic acid (KDO). Biochem. Biophys. Res. Commun. 136 (1986) 329–335. [PMID: 3707579]
[EC 3.2.1.124 created 1989]
 
 
EC 3.2.1.125     
Accepted name: raucaffricine β-glucosidase
Reaction: raucaffricine + H2O = D-glucose + vomilenine
Other name(s): raucaffricine β-D-glucosidase; raucaffricine glucosidase
Systematic name: raucaffricine β-D-glucohydrolase
Comments: Highly specific; some other ajmalan glucoside alkaloids are hydrolysed, but more slowly.
References:
1.  Schübel, H., Stöckigt, J., Feicht, R. and Simon, H. Partial-purification and characterization of raucaffricine β-D-glucosidase from plant cell-suspension cultures of Rauwolfia serpentina benth. Helv. Chim. Acta 69 (1986) 538–547.
[EC 3.2.1.125 created 1989]
 
 
EC 3.2.1.126     
Accepted name: coniferin β-glucosidase
Reaction: coniferin + H2O = D-glucose + coniferol
Other name(s): coniferin-hydrolyzing β-glucosidase
Systematic name: coniferin β-D-glucosidase
Comments: Also hydrolyses syringin, 4-cinnamyl alcohol β-glucoside and, more slowly, some other aryl β-glycosides. A plant cell-wall enzyme involved in the biosynthesis of lignin.
References:
1.  Hösel, W., Surholt, E. and Borgmann, E. Characterization of β-glucosidase isoenzymes possibly involved in lignification from chick pea (Cicer arietinum L.) cell suspension cultures. Eur. J. Biochem. 84 (1978) 487–492. [PMID: 25181]
2.  Marcinowski, S. and Grisebach, H. Enzymology of lignification. Cell-wall bound β-glucosidase for coniferin from spruce (Picea abies) seedlings. Eur. J. Biochem. 87 (1978) 37–44. [PMID: 27355]
[EC 3.2.1.126 created 1989]
 
 
EC 3.2.1.127     
Accepted name: 1,6-α-L-fucosidase
Reaction: Hydrolysis of (1→6)-linkages between α-L-fucose and N-acetyl-D-glucosamine in glycopeptides such as immunoglobulin G glycopeptide and fucosyl-asialo-agalacto-fetuin
Other name(s): α-L-fucosidase; 1,6-L-fucosyl-N-acetyl-D-glucosaminylglycopeptide fucohydrolase
Systematic name: 6-L-fucosyl-N-acetyl-D-glucosaminylglycopeptide fucohydrolase
Comments: The enzyme from Aspergillus niger does not act on 1,2-, 1,3-, or 1,4-L-fucosyl linkages.
References:
1.  Yazawa, S., Madiyalakan, R., Chawda, R.P. and Matta, K.L. α-L-Fucosidase from Aspergillus niger: demonstration of a novel α-L-(1→6)-fucosidase acting on glycopeptides. Biochem. Biophys. Res. Commun. 136 (1986) 563–569. [PMID: 2423086]
[EC 3.2.1.127 created 1989]
 
 
EC 3.2.1.128     
Accepted name: glycyrrhizin hydrolase
Reaction: glycyrrhizin + H2O = β-D-glucuronosyl-(1→2)-D-glucuronate + glycyrrhetinate
Glossary: glycyrrhizin = glycyrrhizinate
glycyrrhetinate = 3-β-glycyrrhetinate = 3β-hydroxy-11-oxoolean-12-en-30-oate
Other name(s): glycyrrhizinate β-glucuronidase; glycyrrhizin β-hydrolase; glycyrrhizinic acid hydrolase
Systematic name: glycyrrhizinate glucuronosylhydrolase
Comments: The enzyme from Aspergillus niger is specific for the hydrolysis of the triterpenoid glycoside glycyrrhizin from roots of Glycyrrhiza sp.
References:
1.  Muro, T., Kuramoto, T., Imoto, K. and Okada, S. Purification and some properties of glycyrrhizinic acid hydrolase from Aspergillus niger GRM3. Agric. Biol. Chem. 50 (1986) 687–692.
[EC 3.2.1.128 created 1989]
 
 
EC 3.2.1.129     
Accepted name: endo-α-sialidase
Reaction: Endohydrolysis of (2→8)-α-sialosyl linkages in oligo- or poly(sialic) acids
Other name(s): endo-N-acylneuraminidase; endoneuraminidase; endo-N-acetylneuraminidase; poly(α-2,8-sialosyl) endo-N-acetylneuraminidase; poly(α-2,8-sialoside) α-2,8-sialosylhydrolase; endosialidase; endo-N
Systematic name: polysialoside (2→8)-α-sialosylhydrolase
Comments: Although the name endo-N-acetylneuraminidase has also been used for this enzyme, this is misleading since its activity is not restricted to acetylated substrates. An exo-α-sialidase activity is listed as EC 3.2.1.18 exo-α-sialidase. See also EC 4.2.2.15 anhydrosialidase.
References:
1.  Finne, J., Mäkelä, P.H. Cleavage of the polysialosyl units of brain glycoproteins by a bacteriophage endosialidase. Involvement of a long oligosaccharide segment in molecular interactions of polysialic acid. J. Biol. Chem. 260 (1985) 1265–1270. [PMID: 3968060]
2.  Hallenbeck, P.C., Vimr, E.R., Yu, F., Bassler, B. and Troy, F.A. Purification and properties of a bacteriophage-induced endo-N-acetylneuraminidase specific for poly-α-2,8-sialosyl carbohydrate units. J. Biol. Chem. 262 (1987) 3553–3561. [PMID: 3546309]
3.  Kitakima, K., Inoue, S., Inoue, Y. and Troy, F.A. Use of a bacteriophage-derived endo-N-acetylneuraminidase and an equine antipolysialyl antibody to characterize the polysialyl residues in salmonid fish egg polysialoglycoproteins. Substrate and immunospecificity studies. J. Biol. Chem. 263 (1988) 18269–18276. [PMID: 3142874]
4.  Kwiatkowski, B., Boscheck, B., Thicle, H. and Stirm, S. Endo-N-acetylneuraminidase associated with bacteriophage particles. J. Virol. 43 (1982) 697–704. [PMID: 7109038]
5.  Pelkonen, S., Pelkonen, J. and Finne, J. Common cleavage pattern of polysialic acid by bacteriophage endosialidases of different properties and origins. J. Virol. 65 (1989) 4409–4416. [PMID: 2778882]
6.  Tombinson, S. and Taylor, P.W. Neuraminidase associated with coliphage E that specifically depolymerizes the Escherichia coli K1 capsular polysaccharide. J. Virol. 55 (1985) 374–378. [PMID: 3894684]
7.  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 3.2.1.129 created 1990, modified 1999]
 
 
EC 3.2.1.130     
Accepted name: glycoprotein endo-α-1,2-mannosidase
Reaction: GlcMan9GlcNAc2-[protein] + H2O = Man8GlcNAc2-[protein] (isomer 8A1,2,3B1,2) + α-D-glucosyl-(1→3)-α-D-mannopyranose
Glossary: GlcMan9GlcNAc2-[protein] = {α-D-Glc-(1→3)-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→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]
Man8GlcNAc2-[protein] (isomer 8A1,2,3B1,2) = {α-D-Man-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→2)-α-D-Man-(1→3)-[α-D-Man-(1→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]
Other name(s): glucosylmannosidase; endo-α-D-mannosidase; endo-α-mannosidase; endomannosidase; glucosyl mannosidase; MANEA (gene name); glycoprotein glucosylmannohydrolase
Systematic name: glycoprotein glucosylmannohydrolase (configuration-retaining)
Comments: The enzyme catalyses the hydrolysis of the terminal α-D-glucosyl-(1→3)-D-mannosyl unit from the GlcMan9(GlcNAc)2 oligosaccharide component of N-glucosylated proteins during their processing in the Golgi apparatus. The name for the isomer is based on a nomenclature proposed by Prien et al [7].
References:
1.  Lubas, W.A. and Spiro, R.G. Golgi endo-α-D-mannosidase from rat liver, a novel N-linked carbohydrate unit processing enzyme. J. Biol. Chem. 262 (1987) 3775–3781. [PMID: 3818665]
2.  Tulsiani, D.R.P., Coleman, V.P. and Touster, O. Asparagine-linked glycoprotein biosynthesis in rat brain: identification of glucosidase I, glucosidase II, and endomannosidase (glucosyl mannosidase). Arch. Biochem. Biophys. 277 (1990) 114–121. [PMID: 2407194]
3.  Hiraizumi, S., Spohr, U. and Spiro, R.G. Ligand affinity chromatographic purification of rat liver Golgi endomannosidase. J. Biol. Chem. 269 (1994) 4697–4700. [PMID: 8106437]
4.  Spiro, M.J., Bhoyroo, V.D. and Spiro, R.G. Molecular cloning and expression of rat liver endo-α-mannosidase, an N-linked oligosaccharide processing enzyme. J. Biol. Chem. 272 (1997) 29356–29363. [PMID: 9361017]
5.  Hamilton, S.R., Li, H., Wischnewski, H., Prasad, A., Kerley-Hamilton, J.S., Mitchell, T., Walling, A.J., Davidson, R.C., Wildt, S. and Gerngross, T.U. Intact α-1,2-endomannosidase is a typical type II membrane protein. Glycobiology 15 (2005) 615–624. [PMID: 15677381]
6.  Hardt, B., Volker, C., Mundt, S., Salska-Navarro, M., Hauptmann, M. and Bause, E. Human endo-α1,2-mannosidase is a Golgi-resident type II membrane protein. Biochimie 87 (2005) 169–179. [PMID: 15760709]
7.  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. [PMID: 19181540]
[EC 3.2.1.130 created 1990, modified 2017]
 
 
EC 3.2.1.131     
Accepted name: xylan α-1,2-glucuronosidase
Reaction: Hydrolysis of (1→2)-α-D-(4-O-methyl)glucuronosyl links in the main chain of hardwood xylans
Other name(s): 1,2-α-glucuronidase; α-(1→2)-glucuronidase; xylan α-D-1,2-(4-O-methyl)glucuronohydrolase
Systematic name: xylan 2-α-D-(4-O-methyl)glucuronohydrolase
References:
1.  Ishihara, M. and Shimizu, K. α-(1→2)-Glucuronidase in the enzymatic saccharification of hardwood xylan .1. Screening of α-glucuronidase producing fungi. Mokuzai Gakkaishi 34 (1988) 58–64.
[EC 3.2.1.131 created 1990]
 
 
EC 3.2.1.132     
Accepted name: chitosanase
Reaction: Endohydrolysis of β-(1→4)-linkages between D-glucosamine residues in a partly acetylated chitosan
Systematic name: chitosan N-acetylglucosaminohydrolase
Comments: A whole spectrum of chitosanases are now known (for more details, see http://rbrzezinski.recherche.usherbrooke.ca/). They can hydrolyse various types of links in chitosan. The only constant property is the endohydrolysis of GlcN-GlcN links, which is common to all known chitosanases. One known chitosanase is limited to this link recognition [4], while the majority can also recognize GlcN-GlcNAc links or GlcNAc-GlcN links but not both. They also do not recognize GlcNAc-GlcNAc links in partly acetylated chitosan.
References:
1.  Fenton, D.M. and Eveleigh, D.E. Purification and mode of action of a chitosanase from Penicillium islandicum. J. Gen. Microbiol. 126 (1981) 151–165.
2.  Saito, J.-I., Kita, A., Higuchi, Y., Nagata, Y., Ando, A. and Miki, K. Crystal structure of chitosanase from Bacillus circulans MH-K1 at 1.6-Å resolution and its substrate recognition mechanism. J. Biol. Chem. 274 (1999) 30818–30825. [PMID: 10521473]
3.  Izume, M., Nagae, S., Kawagishi, H., Mitsutomi, M. and Ohtakara, A. Action pattern of Bacillus sp. No. 7-M chitosanase on partially N-acetylated chitosan. Biosci. Biotechnol. Biochem. 56 (1992) 448–453. [PMID: 1368330]
4.  Marcotte, E.M., Monzingo, A.F., Ernst, S.R., Brzezinski, R. and Robertus, J.D. X-ray structure of an anti-fungal chitosanase from Streptomyces N174. Nat. Struct. Biol. 3 (1996) 155–162. [PMID: 8564542]
[EC 3.2.1.132 created 1990, modified 2004]
 
 
EC 3.2.1.133     
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.
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 3.2.1.134     
Accepted name: difructose-anhydride synthase
Reaction: bis-D-fructose 2′,1:2,1′-dianhydride + H2O = inulobiose
Other name(s): inulobiose hydrolase
Systematic name: bis-D-fructose 2′,1:2,1′-dianhydride fructohydrolase
Comments: Produces difructose anhydride by the reverse reaction of partial hydrolysis, forming an α-fructosidic linkage.
References:
1.  Matsuyama, T. and Tanaka, K. On the enzyme of Aspergillus fumigatus producing difructose anhydride I from inulobiose. Agric. Biol. Chem. 53 (1989) 831–832.
2.  Matsuyama, T., Tanaka, K., Mashiko, M. and Kanamoto, M. Enzymic formation of di-D-fructose 1,2′; 2,1′ dianhydride from inulobiose by Aspergillus fumigatus. J. Biochem. (Tokyo) 92 (1982) 1325–1328. [PMID: 6757245]
[EC 3.2.1.134 created 1992]
 
 
EC 3.2.1.135     
Accepted name: neopullulanase
Reaction: Hydrolysis of pullulan to panose (6-α-D-glucosylmaltose)
Glossary: pullulan = a linear polymer of (1→6)-linked maltotriose units
Other name(s): pullulanase II
Systematic name: pullulan 4-D-glucanohydrolase (panose-forming)
Comments: cf. EC 3.2.1.41 (pullulanase ) and EC 3.2.1.57 (isopullulanase).
References:
1.  Imanaka, T. and Kuriki, T. Pattern of action of Bacillus stearothermophilus neopullulanase on pullulan. J. Bacteriol. 171 (1989) 369–374. [PMID: 2914851]
[EC 3.2.1.135 created 1992]
 
 
EC 3.2.1.136     
Accepted name: glucuronoarabinoxylan endo-1,4-β-xylanase
Reaction: Endohydrolysis of (1→4)-β-D-xylosyl links in some glucuronoarabinoxylans
Other name(s): feraxan endoxylanase; feraxanase; endoarabinoxylanase; glucuronoxylan xylohydrolase; glucuronoxylanase; glucuronoxylan xylanohydrolase; glucuronoarabinoxylan 1,4-β-D-xylanohydrolase
Systematic name: glucuronoarabinoxylan 4-β-D-xylanohydrolase
Comments: High activity towards feruloylated arabinoxylans from cereal plant cell walls.
References:
1.  Nishitani, K. and Nevins, D.J. Enzymic analysis of feruloylated arabinoxylans (Feraxan) derived from Zea mays cell walls. I. Purification of novel enzymes capable of dissociating Feraxan fragments from Zea mays coleoptile cell wall. Plant Physiol. 87 (1988) 883–890. [PMID: 16666240]
[EC 3.2.1.136 created 1992]
 
 
EC 3.2.1.137     
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.
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 3.2.1.138      
Transferred entry: anhydrosialidase. Now EC 4.2.2.15, anhydrosialidase
[EC 3.2.1.138 created 1992, deleted 2003]
 
 
EC 3.2.1.139     
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.
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 3.2.1.140     
Accepted name: lacto-N-biosidase
Reaction: β-D-Gal-(1→3)-β-D-GlcNAc-(1→3)-β-D-Gal-(1→4)-D-Glc + H2O = β-D-Gal-(1→3)-D-GlcNAc + β-D-Gal-(1→4)-D-Glc
Glossary: β-D-Gal-(1→3)-β-D-GlcNAc-(1→3)-β-D-Gal-(1→4)-D-Glc = lacto-N-tetraose
β-D-Gal-(1→3)-D-GlcNAc = lacto-N-biose
β-D-Gal-(1→4)-D-Glc = lactose
Systematic name: oligosaccharide lacto-N-biosylhydrolase
Comments: The enzyme from Streptomyces specifically hydrolyses the terminal lacto-N-biosyl residue (β-D-Gal-(1→3)-D-GlcNAc) from the non-reducing end of oligosaccharides with the structure β-D-Gal-(1→3)-β-D-GlcNAc-(1→3)-β-D-Gal-(1→R). Lacto-N-hexaose (β-D-Gal-(1→3)-β-D-GlcNAc-(1→3)-β-D-Gal-(1→3)-β-D-GlcNAc-(1→3)-β-D-Gal-(1→4)-D-Glc) is hydrolysed to form first lacto-N-tetraose plus lacto-N-biose, with the subsequent formation of lactose. Oligosaccharides in which the non-reducing terminal Gal or the penultimate GlcNAc are replaced by fucose or sialic acid are not substrates. Asialo GM1 tetraose (β-D-Gal-(1→3)-β-D-GalNAc-(1→3)-β-D-Gal-(1→4)-D-Glc) is hydrolysed very slowly, but lacto-N-neotetraose (β-D-Gal-(1→4)-β-D-GalNAc-(1→3)-β-D-Gal-(1→4)-D-Glc) is not a substrate
References:
1.  Sano, M., Hayakawa, K., Kato, I. An enzyme releasing lacto-N-biose from oligosaccharides. Proc. Natl. Acad. Sci. USA 89 (1992) 8512–8516. [PMID: 1528855]
2.  Sano, M., Hayakawa, K., Kato, I. Purification and characterization of an enzyme releasing lacto-N-biose from oligosaccharides with type 1 chain. J. Biol. Chem. 268 (1993) 18560–18566. [PMID: 7689556]
[EC 3.2.1.140 created 1999]
 
 
EC 3.2.1.141     
Accepted name: 4-α-D-{(1→4)-α-D-glucano}trehalose trehalohydrolase
Reaction: hydrolysis of (1→4)-α-D-glucosidic linkage in 4-α-D-[(1→4)-α-D-glucanosyl]n trehalose to yield trehalose and (1→4)-α-D-glucan
Other name(s): malto-oligosyltrehalose trehalohydrolase
Systematic name: 4-α-D-[(1→4)-α-D-glucano]trehalose glucanohydrolase (trehalose-producing)
References:
1.  Maruta, K., Nakada, T., Kubota, M., Chaen, H., Sugimoto, T., Kurimoto, M., Tsujisaka, Y. Formation of trehalose from maltooligosaccharides by a novel enzymatic system. Biosci. Biotechnol. Biochem. 59 (1995) 1829–1834. [PMID: 8534970]
2.  Nakada, T., Maruta, K., Mitsuzumi, H., Kubota, M., Chaen, H., Sugimoto, T. , Kurimoto M., Tsujisaka, Y. Purification and characterization of a novel enzyme, maltooligosyl trehalose trehalohydrolase, from Arthrobacter sp. Q36. Biosci. Biotechnol. Biochem. 59 (1995) 2215–2218. [PMID: 8611745]
3.  Nakada, T., Ikegami, S., Chaen, H., Kubota, M., Fukuda, S., Sugimoto, T., Kurimoto, M., Tsujisaka, Y. Purification and characterization of thermostable maltooligosyl trehalose trehalohydrolase from the thermoacidophilic archaebacterium Sulfolobus acidocaldarius. Biosci. Biotechnol. Biochem. 60 (1996) 267–270. [PMID: 9063974]
[EC 3.2.1.141 created 1999]
 
 
EC 3.2.1.142     
Accepted name: limit dextrinase
Reaction: Hydrolysis of (1→6)-α-D-glucosidic linkages in α- and β-limit dextrins of amylopectin and glycogen, and in amylopectin and pullulan
Glossary: pullulan = a linear polymer of (1→6)-linked maltotriose units
Other name(s): R-enzyme; amylopectin-1,6-glucosidase; dextrin α-1,6-glucanohydrolase
Systematic name: dextrin 6-α-glucanohydrolase
Comments: Plant enzymes with little or no action on glycogen. Action on amylopectin is incomplete, but action on α-limit dextrins is complete. Maltose is the smallest sugar it can release from an α-(1→6)-linkage.
References:
1.  Gordon, R.W., Manners, D.J. and Stark, J.R. The limit dextrinase of the broad bean (Vicia faba). Carbohydr. Res. 42 (1975) 125–134.
2.  Manners, D.J. Observations on the specificity and nomenclature of starch debranching enzymes. J. Appl. Glycosci. 44 (1997) 83–85.
[EC 3.2.1.142 created 2000]
 
 
EC 3.2.1.143     
Accepted name: poly(ADP-ribose) glycohydrolase
Reaction: hydrolyses poly(ADP-D-ribose) at glycosidic (1′′-2′) linkage of ribose-ribose bond to produce free ADP-D-ribose
Glossary: ADP-D-ribose = adenosine 5′-(5-deoxy-D-ribofuranos-5-yl diphosphate)
Comments: Specific to (1′′-2′) linkage of ribose-ribose bond of poly(ADP-D-ribose).
References:
1.  Miwa, M. and Sugimura, T. Splitting of the ribose-ribose linkage of poly(adenosine diphosphate-ribose) by a calf thymus extract. J. Biol. Chem. 246 (1971) 6362–6364. [PMID: 4331388]
2.  Lin, W., Ame, J.C., Aboul-Ela, N., Jacobson, E.L. and Jacobson, M.K. Isolation and characterization of the cDNA encoding bovine poly(ADP-ribose) glycohydrolase. J. Biol. Chem. 272 (1997) 11895–11901. [PMID: 9115250]
[EC 3.2.1.143 created 2000]
 
 
EC 3.2.1.144     
Accepted name: 3-deoxyoctulosonase
Reaction: 3-deoxyoctulosonyl-lipopolysaccharide + H2O = 3-deoxyoctulosonic acid + lipopolysaccharide
Other name(s): α-Kdo-ase
Systematic name: 3-deoxyoctulosonyl-lipopolysaccharide hydrolase
Comments: Releases Kdo (α- and β-linked 3-deoxy-D-manno-octulosonic acid) from different lipopolysaccharides, including Re-LPS from Escherichia coli and Salmonella, Rd-LPS from S. minnesota, and de-O-acyl-re-LPS. 4-Methylumbelliferyl-α-Kdo (α-Kdo-OMec) is also a substrate.
References:
1.  Li, Y.T., Wang, L.X., Pavlova, N.V., Li, S.C. and Lee, Y.C. α-KDOase activity in oyster and synthesis of α- and β-4-methylumbelliferyl ketosides of 3-deoxy-D-manno-octulosonic acid (KDO). J. Biol. Chem. 272 (1997) 26419–26424. [PMID: 9334217]
[EC 3.2.1.144 created 2000]
 
 
EC 3.2.1.145     
Accepted name: galactan 1,3-β-galactosidase
Reaction: Hydrolysis of terminal, non-reducing β-D-galactose residues in (1→3)-β-D-galactopyranans
Other name(s): galactan (1→3)-β-D-galactosidase
Systematic name: galactan 3-β-D-galactosidase
Comments: This enzyme removes not only free galactose, but also 6-glycosylated residues, e.g., (1→6)-β-D-galactobiose, and galactose bearing oligosaccharide chains on O-6. Hence, it releases branches from [arabino-galacto-(1→6)]-(1→3)-β-D-galactans.
References:
1.  Tsumuraya, Y., Mochizuki, N. , Hashimoto Y. and Kovac, P. Purification of exo-(1→3)-D-galactanase of Irpex lacteus (Polyporus tulipiferae) and its action on arabinogalactan-proteins. J. Biol. Chem. 265 (1990) 7207–7215. [PMID: 2158993]
2.  Pellerin, P. and Brillouet, J.M. Purification and properties of an exo-(1→3)-β-D-galactanase from Aspergillus niger. Carbohydr. Res. 264 (1994) 281–291. [PMID: 7805066]
[EC 3.2.1.145 created 2001]
 
 
EC 3.2.1.146     
Accepted name: β-galactofuranosidase
Reaction: Hydrolysis of terminal non-reducing β-D-galactofuranosides, releasing galactose
Other name(s): exo-β-galactofuranosidase; exo-β-D-galactofuranosidase; β-D-galactofuranosidase
Systematic name: β-D-galactofuranoside hydrolase
Comments: The enzyme from Helminthosporium sacchari detoxifies helminthosporoside, a bis(digalactosyl)terpene produced by this fungus, by releasing its four molecules of bound galactose.
References:
1.  Rietschel-Berst, M., Jentoft, N.H., Rick, P.D., Pletcher, C., Fang, F. and Gander, J.E. Extracellular exo-β-galactofuranosidase from Penicillium charlesii: isolation, purification, and properties. J. Biol. Chem. 252 (1977) 3219–3226. [PMID: 863879]
2.  Daley, L.S. and Strobel, G.A. β-Galactofuranosidase activity in Helminthosporium sacchari and its relationship to the production of helminthosporoside. Plant Sci. Lett. 30 (1983) 145–154.
3.  Cousin, M.A., Notermans, S., Hoogerhout, P. and Van Boom, J.H. Detection of β-galactofuranosidase production by Penicillium and Aspergillus species using 4-nitrophenyl β-D-galactofuranoside. J. Appl. Bacteriol. 66 (1989) 311–317. [PMID: 2502527]
4.  Miletti, L.C., Marino, C., Marino, K., de Lederkremer, R.M., Colli, W. and Alves, M.J.M. Immobilized 4-aminophenyl-1-thio-β-D-galactofuranoside as a matrix for affinity purification of an exo-β-D-galactofuranosidase. Carbohydr. Res. 320 (1999) 176–182. [PMID: 10573856]
[EC 3.2.1.146 created 2001]
 
 
EC 3.2.1.147     
Accepted name: thioglucosidase
Reaction: a thioglucoside + H2O = a sugar + a thiol
Other name(s): myrosinase; sinigrinase; sinigrase
Systematic name: thioglucoside glucohydrolase
Comments: Has a wide specificity for thioglycosides.
References:
1.  Goodman, I., Fouts, J.R., Bresnick, E., Menegas, R. and Hitchings, G.H. A mammalian thioglucosidase. Science 130 (1959) 450–451. [PMID: 13675769]
2.  Pigman, W.W. Action of almond emulsin on the phenyl glucosides of synthetic sugars and on β-thiophenyl d-glucoside. J. Res. Nat. Bur. Stand. 26 (1941) 197–204.
[EC 3.2.1.147 created 1972 as EC 3.2.3.1, transferred 2001 to EC 3.2.1.147]
 
 
EC 3.2.1.148      
Deleted entry: ribosylhomocysteinase. This enzyme was transferred to EC 3.13.1.2, 5-deoxyribos-5-ylhomocysteinase, which has since been deleted. The activity is most probably attributable to EC 4.4.1.21, S-ribosylhomocysteine lyase
[EC 3.2.1.148 created 1972 as EC 3.3.1.3, transferred 2001 to EC 3.2.1.148, deleted 2004]
 
 
EC 3.2.1.149     
Accepted name: β-primeverosidase
Reaction: a 6-O-(β-D-xylopyranosyl)-β-D-glucopyranoside + H2O = 6-O-(β-D-xylopyranosyl)-β-D-glucopyranose + an alcohol
Glossary: primeverose = 6-O-(β-D-xylopyranosyl)-D-glucose
vicianose = 6-O-(α-L-arabinopyranosyl)-D-glucose
Systematic name: 6-O-(β-D-xylopyranosyl)-β-D-glucopyranoside 6-O-(β-D-xylosyl)-β-D-glucohydrolase
Comments: The enzyme is responsible for the formation of the alcoholic aroma in oolong and black tea. In addition to β-primeverosides [i.e. 6-O-(β-D-xylopyranosyl)-β-D-glucopyranosides], it also hydrolyses 6-O-(β-D-apiofuranosyl)-β-D-glucopyranosides and, less rapidly, β-vicianosides and 6-O-(α-L-arabinofuranosyl)-β-D-glucopyranosides, but not β-glucosides. Geranyl-, linaloyl-, benzyl- and p-nitrophenol glycosides are all hydrolysed.
References:
1.  Ijima, Y., Ogawa, K., Watanabe, N., Usui, T., Ohnishi-Kameyama, M., Nagata, T. and Sakata, K. Characterization of β-primeverosidase, being concerned with alcoholic aroma formation in tea leaves to be processed into black tea, and preliminary observations on its substrate specificity. J. Agric. Food Chem. 46 (1998) 1712–1718.
2.  Ogawa, K., Ijima, Y., Guo, W., Watanabe, N., Usui, T., Dong, S., Tong, Q. and Sakata, K. Purification of a β-primeverosidase concerned with alcoholic aroma formation in tea leaves (cv. Shuxian) to be processed to oolong tea. J. Agric. Food Chem. 45 (1997) 877–882.
[EC 3.2.1.149 created 2001]
 
 
EC 3.2.1.150     
Accepted name: oligoxyloglucan reducing-end-specific cellobiohydrolase
Reaction: Hydrolysis of cellobiose from the reducing end of xyloglucans consisting of a (1→4)-β-linked glucan carrying α-D-xylosyl groups on O-6 of the glucose residues. To be a substrate, the first residue must be unsubstituted, the second residue may bear a xylosyl group, whether further glycosylated or not, and the third residue, which becomes the new terminus by the action of the enzyme, is preferably xylosylated, but this xylose residue must not be further substituted.
Systematic name: oligoxyloglucan reducing-end cellobiohydrolase
Comments: The enzyme is found in the fungus Geotrichum sp. M128. The substrate is a hemicellulose found in plant cell walls.
References:
1.  Yaoi, K. and Mitsuishi, Y. Purification, characterization, cloning, and expression of a novel xyloglucan-specific glycosidase, oligoxyloglucan reducing end-specific cellobiohydrolase. J. Biol. Chem. 277 (2002) 48276–48281. [PMID: 12374797]
[EC 3.2.1.150 created 2003]
 
 
EC 3.2.1.151     
Accepted name: xyloglucan-specific endo-β-1,4-glucanase
Reaction: xyloglucan + H2O = xyloglucan oligosaccharides
Other name(s): XEG; xyloglucan endo-β-1,4-glucanase; xyloglucanase; xyloglucanendohydrolase; XH; 1,4-β-D-glucan glucanohydrolase
Systematic name: [(1→6)-α-D-xylo]-(1→4)-β-D-glucan glucanohydrolase
Comments: The enzyme from Aspergillus aculeatus is specific for xyloglucan and does not hydrolyse other cell-wall components. The reaction involves endohydrolysis of 1,4-β-D-glucosidic linkages in xyloglucan with retention of the β-configuration of the glycosyl residues.
References:
1.  Pauly, M., Andersen, L.N., Kaupinnen, S., Kofod, L.V., York, W.S., Albersheim, P. and Darvill, A. A xyloglucan specific endo-β-1,4-glucanase from Aspergillus aculeatus: expression cloning in yeast, purification and characterization of the recombinant enzyme. Glycobiology 9 (1999) 93–100. [PMID: 9884411]
2.  Grishutin, S.G., Gusakov, A.V., Markov, A.V., Ustinov, B.B., Semenova, M.V. and Sinitsyn, A.P. Specific xyloglucanases as a new class of polysaccharide-degrading enzymes. Biochim. Biophys. Acta 1674 (2004) 268–281. [PMID: 15541296]
[EC 3.2.1.151 created 2003]
 
 
EC 3.2.1.152     
Accepted name: mannosylglycoprotein endo-β-mannosidase
Reaction: Hydrolysis of the α-D-mannosyl-(1→6)-β-D-mannosyl-(1→4)-N-acetyl-β-D-glucosaminyl-(1→4)-N-acetyl-β-D-glucosaminyl sequence of glycoprotein to α-D-mannosyl-(1→6)-D-mannose and N-acetyl-β-D-glucosaminyl-(1→4)-N-acetyl-β-D-glucosaminyl sequences
Other name(s): endo-β-mannosidase
Comments: The substrate group is a substituent on N-4 of an asparagine residue in the glycoprotein. The mannose residue at the non-reducing end of the sequence may carry further α-D-mannosyl groups on O-3 or O-6, but such a substituent on O-3 of the β-D-mannosyl group prevents the action of the enzyme. The enzyme was obtained from the lily, Lilium longiflorum.
References:
1.  Ishimizu, T., Sasaki, A., Okutani, S., Maeda, M., Yamagishi, M. and Hase, S. Endo-β-mannosidase, a plant enzyme acting on N-glycan. Purification, molecular cloning, and characterization. J. Biol. Chem. 279 (2004) 38555–38562. [PMID: 15247239]
2.  Sasaki, A., Yamagishi, M., Mega, T., Norioka, S., Natsuka, S. and Hase, S. Partial purification and characterization of a novel endo-β-mannosidase acting on N-linked sugar chains from Lilium longiflorum thumb. J. Biochem. (Tokyo) 125 (1999) 363–367. [PMID: 9990135]
[EC 3.2.1.152 created 2005]
 
 
EC 3.2.1.153     
Accepted name: fructan β-(2,1)-fructosidase
Reaction: Hydrolysis of terminal, non-reducing (2→1)-linked β-D-fructofuranose residues in fructans
Other name(s): β-(2-1)-D-fructan fructohydrolase; β-(2-1)fructan exohydrolase; inulinase; 1-FEH II; 1-fructan exohydrolase; 1-FEH w1; 1-FEH w2; β-(2-1)-linkage-specific fructan-β-fructosidase; β-(2,1)-D-fructan fructohydrolase
Systematic name: β-(2→1)-D-fructan fructohydrolase
Comments: Possesses one of the activities of EC 3.2.1.80, fructan β-fructosidase. While the best substrates are the inulin-type fructans, such as 1-kestose [β-D-fructofuranosyl-(2→1)-β-D-fructofuranosyl α-D-glucopyranoside] and 1,1-nystose [β-D-fructofuranosyl-(2→1)-β-D-fructofuranosyl-(2→1)-β-D-fructofuranosyl α-D-glucopyranoside], some (but not all) levan-type fructans can also be hydrolysed, but more slowly [see EC 3.2.1.154, fructan β-(2,6)-fructosidase]. Sucrose, while being a very poor substrate, can substantially inhibit enzyme activity in some cases.
References:
1.  De Roover, J., Van Laere, A., De Winter, M., Timmermans, J.W. and Van den Ende, W. Purification and properties of a second fructan exohydrolase from the roots of Cichorium intybus. Physiol. Plant. 106 (1999) 28–34.
2.  Van den Ende, W., Clerens, S., Vergauwen, R., Van Riet, L., Van Laere, A., Yoshida, M. and Kawakami, A. Fructan 1-exohydrolases. β-(2,1)-Trimmers during graminan biosynthesis in stems of wheat? Purification, characterization, mass mapping, and cloning of two fructan 1-exohydrolase isoforms. Plant Physiol. 131 (2003) 621–631. [PMID: 12586886]
[EC 3.2.1.153 created 2005]
 
 
EC 3.2.1.154     
Accepted name: fructan β-(2,6)-fructosidase
Reaction: Hydrolysis of terminal, non-reducing (2→6)-linked β-D-fructofuranose residues in fructans
Other name(s): β-(2-6)-fructan exohydrolase; levanase; 6-FEH; β-(2,6)-D-fructan fructohydrolase
Systematic name: (2→6)-β-D-fructan fructohydrolase
Comments: Possesses one of the activities of EC 3.2.1.80, fructan β-fructosidase. While the best substrates are the levan-type fructans such as 6-kestotriose [β-D-fructofuranosyl-(2→6)-β-D-fructofuranosyl α-D-glucopyranoside] and 6,6-kestotetraose [β-D-fructofuranosyl-(2→6)-β-D-fructofuranosyl-(2→6)-β-D-fructofuranosyl α-D-glucopyranoside], some (but not all) inulin-type fructans can also be hydrolysed, but more slowly [cf. EC 3.2.1.153, fructan β-(2,1)-fructosidase]. Sucrose, while being a very poor substrate, can substantially inhibit enzyme activity in some cases.
References:
1.  Marx, S.P., Nösberger, J. and Frehner, M. Hydrolysis of fructan in grasses: A β-(2-6)-linkage specific fructan-β-fructosidase from stubble of Lolium perenne. New Phytol. 135 (1997) 279–290.
2.  Van den Ende, W., De Coninck, B., Clerens, S., Vergauwen, R. and Van Laere, A. Unexpected presence of fructan 6-exohydrolases (6-FEHs) in non-fructan plants: characterization, cloning, mass mapping and functional analysis of a novel 'cell-wall invertase-like' specific 6-FEH from sugar beet (Beta vulgaris L.). Plant J. 36 (2003) 697–710. [PMID: 14617070]
3.  Henson, C.A. and Livingston, D.P. , III. Purification and characterization of an oat fructan exohydrolase that preferentially hydrolyzes β-2,6-fructans. Plant Physiol. 110 (1996) 639–644. [PMID: 8742337]
[EC 3.2.1.154 created 2005]
 
 
EC 3.2.1.155     
Accepted name: xyloglucan-specific endo-processive β-1,4-glucanase
Reaction: Hydrolysis of (1→4)-D-glucosidic linkages in xyloglucans so as to successively remove oligosaccharides from the newly-formed chain end after endo-initiation on a polymer molecule
Other name(s): Cel74A; [(1→6)-α-D-xylo]-(1→4)-β-D-glucan exo-glucohydrolase (ambiguous); xyloglucan-specific exo-β-1,4-glucanase (ambiguous)
Systematic name: [(1→6)-α-D-xylo]-(1→4)-β-D-glucan endo-processive glucohydrolase
Comments: The enzyme removes branched oligosaccharides, containing preferentially four glucoside residues in the main chain, from xyloglucan molecules in a processive manner after the initial endo-type attack on a polysaccharide [1-5]. Hydrolysis occurs at either the unsubstituted D-glucopyranose residue in the main backbone and/or the D-glucopyranose residue bearing a xylosyl group [1-5]. The enzyme does not display activity, or shows very low activity, towards other β-D-glucans [1,2,4,5].
References:
1.  Grishutin, S.G., Gusakov, A.V., Markov, A.V., Ustinov, B.B., Semenova, M.V. and Sinitsyn, A.P. Specific xyloglucanases as a new class of polysaccharide-degrading enzymes. Biochim. Biophys. Acta 1674 (2004) 268–281. [PMID: 15541296]
2.  Ichinose, H., Araki, Y., Michikawa, M., Harazono, K., Yaoi, K., Karita, S. and Kaneko, S. Characterization of an endo-processive-type xyloglucanase having a β-1,4-glucan-binding module and an endo-type xyloglucanase from Streptomyces avermitilis. Appl. Environ. Microbiol. 78 (2012) 7939–7945. [PMID: 22941084]
3.  Matsuzawa, T., Saito, Y. and Yaoi, K. Key amino acid residues for the endo-processive activity of GH74 xyloglucanase. FEBS Lett. 588 (2014) 1731–1738. [PMID: 24657616]
4.  Arnal, G., Stogios, P.J., Asohan, J., Skarina, T., Savchenko, A. and Brumer, H. Structural enzymology reveals the molecular basis of substrate regiospecificity and processivity of an exemplar bacterial glycoside hydrolase family 74 endo-xyloglucanase. Biochem. J. 475 (2018) 3963–3978. [PMID: 30463871]
5.  Arnal, G., Stogios, P.J., Asohan, J., Attia, M.A., Skarina, T., Viborg, A.H., Henrissat, B., Savchenko, A. and Brumer, H. Substrate specificity, regiospecificity, and processivity in glycoside hydrolase family 74. J. Biol. Chem. 294 (2019) 13233–13247. [PMID: 31324716]
6.  Gusakov, A.V. Additional sequence and structural characterization of an endo-processive GH74 xyloglucanase from Myceliophthora thermophila and the revision of the EC 3.2.1.155 entry. Biochim. Biophys. Acta. 1864:129511 (2020). [PMID: 31911243]
[EC 3.2.1.155 created 2005, withdrawn at public-review stage, modified and reinstated 2006, modified 2020]
 
 
EC 3.2.1.156     
Accepted name: oligosaccharide reducing-end xylanase
Reaction: Hydrolysis of (1→4)-β-D-xylose residues from the reducing end of oligosaccharides
Other name(s): Rex; reducing end xylose-releasing exo-oligoxylanase
Systematic name: β-D-xylopyranosyl-(1→4)-β-D-xylopyranose reducing-end xylanase
Comments: The enzyme, originally isolated from the bacterium Bacillus halodurans C-125, releases the xylose unit at the reducing end of oligosaccharides ending with the structure β-D-xylopyranosyl-(1→4)-β-D-xylopyranosyl-(1→4)-β-D-xylopyranose, leaving the new reducing end in the α configuration. It is specific for the β anomers of xylooligosaccharides whose degree of polymerization is equal to or greater than 3. The penultimate residue must be β-D-xylopyranose, but replacing either of the flanking residues with glucose merely slows the rate greatly.
References:
1.  Honda, Y. and Kitaoka, M. A family 8 glycoside hydrolase from Bacillus halodurans C-125 (BH2105) is a reducing end xylose-releasing exo-oligoxylanase. J. Biol. Chem. 279 (2004) 55097–55103. [PMID: 15491996]
2.  Fushinobu, S., Hidaka, M., Honda, Y., Wakagi, T., Shoun, H. and Kitaoka, M. Structural basis for the specificity of the reducing end xylose-releasing exo-oligoxylanase from Bacillus halodurans C-125. J. Biol. Chem. 280 (2005) 17180–17186. [PMID: 15718242]
[EC 3.2.1.156 created 2005]
 
 
EC 3.2.1.157     
Accepted name: ι-carrageenase
Reaction: Endohydrolysis of (1→4)-β-D-linkages between D-galactose 4-sulfate and 3,6-anhydro-D-galactose-2-sulfate in ι-carrageenans
Glossary: In the field of oligosaccharides derived from agarose, carrageenans, etc., in which alternate residues are 3,6-anhydro sugars, the prefix ’neo’ designates an oligosaccharide whose non-reducing end is the anhydro sugar, and the absence of this prefix means that it is not.
For example:
ι-neocarrabiose = 3,6-anhydro-2-O-sulfo-α-D-galactopyranosyl-(1→3)-4-O-sulfo-D-galactose
ι-carrabiose = 4-O-sulfo-β-D-galactopyranosyl-(1→4)-3,6-anhydro-2-O-sulfo-D-galactose
Systematic name: ι-carrageenan 4-β-D-glycanohydrolase (configuration-inverting)
Comments: The main products of hydrolysis are ι-neocarratetraose sulfate and ι-neocarrahexaose sulfate. ι-Neocarraoctaose is the shortest substrate oligomer that can be cleaved. Unlike EC 3.2.1.81, β-agarase and EC 3.2.1.83, κ-carrageenase, this enzyme proceeds with inversion of the anomeric configuration. ι-Carrageenan differs from κ-carrageenan by possessing a sulfo group on O-2 of the 3,6-anhydro-D-galactose residues, in addition to that present in the κ-compound on O-4 of the D-galactose residues.
References:
1.  Barbeyron, T., Michel, G., Potin, P., Henrissat, B. and Kloareg, B. ι-Carrageenases constitute a novel family of glycoside hydrolases, unrelated to that of κ-carrageenases. J. Biol. Chem. 275 (2000) 35499–35505. [PMID: 10934194]
2.  Michel, G., Chantalat, L., Fanchon, E., Henrissat, B., Kloareg, B. and Dideberg, O. The ι-carrageenase of Alteromonas fortis. A β-helix fold-containing enzyme for the degradation of a highly polyanionic polysaccharide. J. Biol. Chem. 276 (2001) 40202–40209. [PMID: 11493601]
3.  Michel, G., Helbert, W., Kahn, R., Dideberg, O. and Kloareg, B. The structural bases of the processive degradation of ι-carrageenan, a main cell wall polysaccharide of red algae. J. Mol. Biol. 334 (2003) 421–433. [PMID: 14623184]
[EC 3.2.1.157 created 2006]
 
 
EC 3.2.1.158     
Accepted name: α-agarase
Reaction: Endohydrolysis of (1→3)-α-L-galactosidic linkages in agarose, yielding agarotetraose as the major product
Glossary: agarose = a linear polysaccharide produced by some members of the Rhodophyta (red algae) made up from alternating D-galactose and 3,6-anhydro-α-L-galactopyranose residues joined by α-(1→3)- and β-(1→4)-linkages. In the field of oligosaccharides derived from agarose, carrageenans, etc., in which alternate residues are 3,6-anhydro sugars, the prefix ’neo’ designates an oligosaccharide whose non-reducing end is the anhydro sugar, and the absence of this prefix means that it is not.
For example:
neoagarobiose = 3,6-anhydro-α-L-galactopyranosyl-(1→3)-D-galactose
agarobiose = β-D-galactopyranosyl-(1→4)-3,6-anhydro-L-galactose
Other name(s): agarase (ambiguous); agaraseA33
Systematic name: agarose 3-glycanohydrolase
Comments: Requires Ca2+. The enzyme from Thalassomonas sp. can use agarose, agarohexaose and neoagarohexaose as substrate. The products of agarohexaose hydrolysis are dimers and tetramers, with agarotetraose being the predominant product, whereas hydrolysis of neoagarohexaose gives rise to two types of trimer. While the enzyme can also hydrolyse the highly sulfated agarose porphyran very efficiently, it cannot hydrolyse the related compounds κ-carrageenan (see EC 3.2.1.83) and ι-carrageenan (see EC 3.2.1.157) [2]. See also EC 3.2.1.81, β-agarase.
References:
1.  Potin, P., Richard, C., Rochas, C. and Kloareg, B. Purification and characterization of the α-agarase from Alteromonas agarlyticus (Cataldi) comb. nov., strain GJ1B. Eur. J. Biochem. 214 (1993) 599–607. [PMID: 8513809]
2.  Ohta, Y., Hatada, Y., Miyazaki, M., Nogi, Y., Ito, S. and Horikoshi, K. Purification and characterization of a novel α-agarase from a Thalassomonas sp. Curr. Microbiol. 50 (2005) 212–216. [PMID: 15902469]
[EC 3.2.1.158 created 2006]
 
 
EC 3.2.1.159     
Accepted name: α-neoagaro-oligosaccharide hydrolase
Reaction: Hydrolysis of the (1→3)-α-L-galactosidic linkages of neoagaro-oligosaccharides that are smaller than a hexamer, yielding 3,6-anhydro-L-galactose and D-galactose
Glossary: In the field of oligosaccharides derived from agarose, carrageenans, etc., in which alternate residues are 3,6-anhydro sugars, the prefix ’neo’ designates an oligosaccharide whose non-reducing end is the anhydro sugar, and the absence of this prefix means that it is not.
For example:
neoagarobiose = 3,6-anhydro-α-L-galactopyranosyl-(1→3)-D-galactose
agarobiose = β-D-galactopyranosyl-(1→4)-3,6-anhydro-L-galactose
Other name(s): α-neoagarooligosaccharide hydrolase; α-NAOS hydrolase
Systematic name: α-neoagaro-oligosaccharide 3-glycohydrolase
Comments: When neoagarohexaose is used as a substrate, the oligosaccharide is cleaved at the non-reducing end to produce 3,6-anhydro-L-galactose and agaropentaose, which is further hydrolysed to agarobiose and agarotriose. With neoagarotetraose as substrate, the products are predominantly agarotriose and 3,6-anhydro-L-galactose. In Vibrio sp. the actions of EC 3.2.1.81, β-agarase and EC 3.2.1.159 can be used to degrade agarose to 3,6-anhydro-L-galactose and D-galactose.
References:
1.  Sugano, Y., Kodama, H., Terada, I., Yamazaki, Y. and Noma, M. Purification and characterization of a novel enzyme, α-neoagarooligosaccharide hydrolase (α-NAOS hydrolase), from a marine bacterium, Vibrio sp. strain JT0107. J. Bacteriol. 176 (1994) 6812–6818. [PMID: 7961439]
[EC 3.2.1.159 created 2006]
 
 
EC 3.2.1.160      
Deleted entry: xyloglucan-specific exo-β-1,4-glucanase. The enzyme was shown to be identical to EC 3.2.1.155, xyloglucan-specific exo-β-1,4-glucanase, during the public-review process so was withdrawn before being made official
[EC 3.2.1.160 created 2006, deleted 2006]
 
 
EC 3.2.1.161     
Accepted name: β-apiosyl-β-glucosidase
Reaction: 7-[β-D-apiofuranosyl-(1→6)-β-D-glucopyranosyloxy]isoflavonoid + H2O = a 7-hydroxyisoflavonoid + β-D-apiofuranosyl-(1→6)-D-glucose
Other name(s): isoflavonoid-7-O-β[D-apiosyl-(1→6)-β-D-glucoside] disaccharidase; isoflavonoid 7-O-β-apiosyl-glucoside β-glucosidase; furcatin hydrolase
Systematic name: 7-[β-D-apiofuranosyl-(1→6)-β-D-glucopyranosyloxy]isoflavonoid β-D-apiofuranosyl-(1→6)-D-glucohydrolase
Comments: The enzyme from the tropical tree Dalbergia nigrescens Kurz belongs in glycosyl hydrolase family 1. The enzyme removes disaccharides from the natural substrates dalpatein 7-O-β-D-apiofuranosyl-(1→6)-β-D-glucopyranoside and 7-hydroxy-2′,4′,5′,6-tetramethoxy-7-O-β-D-apiofuranosyl-(1→6)-β-D-glucopyranoside (dalnigrein 7-O-β-D-apiofuranosyl-(1→6)-β-D-glucopyranoside) although it can also remove a single glucose residue from isoflavonoid 7-O-glucosides [2]. Daidzin and genistin are also substrates.
References:
1.  Hosel, W. and Barz, W. β-Glucosidases from Cicer arietinum L. Purification and Properties of isoflavone-7-O-glucoside-specific β-glucosidases. Eur. J. Biochem. 57 (1975) 607–616. [PMID: 240725]
2.  Chuankhayan, P., Hua, Y., Svasti, J., Sakdarat, S., Sullivan, P.A. and Ketudat Cairns, J.R. Purification of an isoflavonoid 7-O-β-apiosyl-glucoside β-glycosidase and its substrates from Dalbergia nigrescens Kurz. Phytochemistry 66 (2005) 1880–1889. [PMID: 16098548]
3.  Ahn, Y.O., Mizutani, M., Saino, H. and Sakata, K. Furcatin hydrolase from Viburnum furcatum Blume is a novel disaccharide-specific acuminosidase in glycosyl hydrolase family 1. J. Biol. Chem. 279 (2004) 23405–23414. [PMID: 14976214]
[EC 3.2.1.161 created 2006]
 
 
EC 3.2.1.162     
Accepted name: λ-carrageenase
Reaction: Endohydrolysis of (1→4)-β-linkages in the backbone of λ-carrageenan, resulting in the tetrasaccharide α-D-Galp2,6S2-(1→3)-β-D-Galp2S-(1→4)-α-D-Galp2,6S2-(1→3)-D-Galp2S
Glossary: For diagram of the structures of carrageenans, click here
Other name(s): endo-β-1,4-carrageenose 2,6,2′-trisulfate-hydrolase
Systematic name: endo-(1→4)-β-carrageenose 2,6,2′-trisulfate-hydrolase
Comments: The enzyme from Pseudoalteromonas sp. is specific for λ-carrageenan. ι-Carrageenan (see EC 3.2.1.157, ι-carrageenase), κ-carrageenan (see EC 3.2.1.83, κ-carrageenase), agarose and porphyran are not substrates.
References:
1.  Ohta, Y. and Hatada, Y. A novel enzyme, λ-carrageenase, isolated from a deep-sea bacterium. J. Biochem. (Tokyo) 140 (2006) 475–481. [PMID: 16926183]
[EC 3.2.1.162 created 2007]
 
 
EC 3.2.1.163     
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.
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. [PMID: 15721331]
[EC 3.2.1.163 created 2007]
 
 
EC 3.2.1.164     
Accepted name: galactan endo-1,6-β-galactosidase
Reaction: Endohydrolysis of (1→6)-β-D-galactosidic linkages in arabinogalactan proteins and (1→3):(1→6)-β-galactans to yield galactose and (1→6)-β-galactobiose as the final products
Other name(s): endo-1,6-β-galactanase
Systematic name: endo-β-(1→6)-galactanase
Comments: The enzyme specifically hydrolyses 1,6-β-D-galactooligosaccharides with a degree of polymerization (DP) higher than 3, and their acidic derivatives with 4-O-methylglucosyluronate or glucosyluronate groups at the non-reducing terminals [2]. 1,3-β-D- and 1,4-β-D-galactosyl residues cannot act as substrates. The enzyme can also hydrolyse α-L-arabinofuranosidase-treated arabinogalactan protein (AGP) extracted from radish roots [2,3]. AGPs are thought to be involved in many physiological events, such as cell division, cell expansion and cell death [3].
References:
1.  Brillouet, J.-M., Williams, P. and Moutounet, M. Purification and some properties of a novel endo-β-(1→6)-D-galactanase from Aspergillus niger. Agric. Biol. Chem. 55 (1991) 1565–1571.
2.  Okemoto, K., Uekita, T., Tsumuraya, Y., Hashimoto, Y. and Kasama, T. Purification and characterization of an endo-β-(1→6)-galactanase from Trichoderma viride. Carbohydr. Res. 338 (2003) 219–230. [PMID: 12543554]
3.  Kotake, T., Kaneko, S., Kubomoto, A., Haque, M.A., Kobayashi, H. and Tsumuraya, Y. Molecular cloning and expression in Escherichia coli of a Trichoderma viride endo-β-(1→6)-galactanase gene. Biochem. J. 377 (2004) 749–755. [PMID: 14565843]
[EC 3.2.1.164 created 2007]
 
 
EC 3.2.1.165     
Accepted name: exo-1,4-β-D-glucosaminidase
Reaction: Hydrolysis of chitosan or chitosan oligosaccharides to remove successive D-glucosamine residues from the non-reducing termini
Glossary: GlcN = D-glucosamine = 2-amino-2-deoxy-D-glucopyranose
GlcNAc = N-acetyl-D-glucosamine
Other name(s): CsxA; GlcNase; exochitosanase; GlmA; exo-β-D-glucosaminidase; chitosan exo-1,4-β-D-glucosaminidase
Systematic name: chitosan exo-(1→4)-β-D-glucosaminidase
Comments: Chitosan is a partially or totally N-deacetylated chitin derivative that is found in the cell walls of some phytopathogenic fungi and comprises D-glucosamine residues with a variable content of GlcNAc residues [4]. Acts specifically on chitooligosaccharides and chitosan, having maximal activity on chitotetraose, chitopentaose and their corresponding alcohols [1]. The enzyme can degrade GlcN-GlcNAc but not GlcNAc-GlcNAc [3]. A member of the glycoside hydrolase family 2 (GH-2) [4].
References:
1.  Nanjo, F., Katsumi, R. and Sakai, K. Purification and characterization of an exo-β-D-glucosaminidase, a novel type of enzyme, from Nocardia orientalis. J. Biol. Chem. 265 (1990) 10088–10094. [PMID: 2351651]
2.  Nogawa, M., Takahashi, H., Kashiwagi, A., Ohshima, K., Okada, H. and Morikawa, Y. Purification and characterization of exo-β-D-glucosaminidase from a cellulolytic fungus, Trichoderma reesei PC-3-7. Appl. Environ. Microbiol. 64 (1998) 890–895. [PMID: 16349528]
3.  Fukamizo, T., Fleury, A., Côté, N., Mitsutomi, M. and Brzezinski, R. Exo-β-D-glucosaminidase from Amycolatopsis orientalis: catalytic residues, sugar recognition specificity, kinetics, and synergism. Glycobiology 16 (2006) 1064–1072. [PMID: 16877749]
4.  Côté, N., Fleury, A., Dumont-Blanchette, E., Fukamizo, T., Mitsutomi, M. and Brzezinski, R. Two exo-β-D-glucosaminidases/exochitosanases from actinomycetes define a new subfamily within family 2 of glycoside hydrolases. Biochem. J. 394 (2006) 675–686. [PMID: 16316314]
5.  Ike, M., Isami, K., Tanabe, Y., Nogawa, M., Ogasawara, W., Okada, H. and Morikawa, Y. Cloning and heterologous expression of the exo-β-D-glucosaminidase-encoding gene (gls93) from a filamentous fungus, Trichoderma reesei PC-3-7. Appl. Microbiol. Biotechnol. 72 (2006) 687–695. [PMID: 16636831]
[EC 3.2.1.165 created 2008]
 
 
EC 3.2.1.166     
Accepted name: heparanase
Reaction: endohydrolysis of (1→4)-β-D-glycosidic bonds of heparan sulfate chains in heparan sulfate proteoglycan
Other name(s): Hpa1 heparanase; Hpa1; heparanase 1; heparanase-1; C1A heparanase; HPSE
Systematic name: heparan sulfate N-sulfo-D-glucosamine endoglucanase
Comments: Heparanase cleaves the linkage between a glucuronic acid unit and an N-sulfo glucosamine unit carrying either a 3-O-sulfo or a 6-O-sulfo group [2]. Heparanase-1 cuts macromolecular heparin into fragments of 5000–20000 Da [5]. The enzyme cleaves the heparan sulfate glycosaminoglycans from proteoglycan core proteins and degrades them to small oligosaccharides. Inside cells, the enzyme is important for the normal catabolism of heparan sulfate proteoglycans, generating glycosaminoglycan fragments that are then transported to lysosomes and completely degraded. When secreted, heparanase degrades basement membrane heparan sulfate glycosaminoglycans at sites of injury or inflammation, allowing extravasion of immune cells into nonvascular spaces and releasing factors that regulate cell proliferation and angiogenesis [1].
References:
1.  Bame, K.J. Heparanases: endoglycosidases that degrade heparan sulfate proteoglycans. Glycobiology 11 (2001) 91R–98R. [PMID: 11445547]
2.  Peterson, S.B. and Liu, J. Unraveling the specificity of heparanase utilizing synthetic substrates. J. Biol. Chem. 285 (2010) 14504–14513. [PMID: 20181948]
3.  Pikas, D.S., Li, J.P., Vlodavsky, I. and Lindahl, U. Substrate specificity of heparanases from human hepatoma and platelets. J. Biol. Chem. 273 (1998) 18770–18777. [PMID: 9668050]
4.  Okada, Y., Yamada, S., Toyoshima, M., Dong, J., Nakajima, M. and Sugahara, K. Structural recognition by recombinant human heparanase that plays critical roles in tumor metastasis. Hierarchical sulfate groups with different effects and the essential target disulfated trisaccharide sequence. J. Biol. Chem. 277 (2002) 42488–42495. [PMID: 12213822]
5.  Vreys, V. and David, G. Mammalian heparanase: what is the message. J. Cell. Mol. Med. 11 (2007) 427–452. [PMID: 17635638]
6.  Gong, F., Jemth, P., Escobar Galvis, M.L., Vlodavsky, I., Horner, A., Lindahl, U. and Li, J.P. Processing of macromolecular heparin by heparanase. J. Biol. Chem. 278 (2003) 35152–35158. [PMID: 12837765]
7.  Toyoshima, M. and Nakajima, M. Human heparanase. Purification, characterization, cloning, and expression. J. Biol. Chem. 274 (1999) 24153–24160. [PMID: 10446189]
8.  Miao, H.Q., Navarro, E., Patel, S., Sargent, D., Koo, H., Wan, H., Plata, A., Zhou, Q., Ludwig, D., Bohlen, P. and Kussie, P. Cloning, expression, and purification of mouse heparanase. Protein Expr. Purif. 26 (2002) 425–431. [PMID: 12460766]
9.  Hammond, E., Li, C.P. and Ferro, V. Development of a colorimetric assay for heparanase activity suitable for kinetic analysis and inhibitor screening. Anal. Biochem. 396 (2010) 112–116. [PMID: 19748475]
[EC 3.2.1.166 created 2010]
 
 
EC 3.2.1.167     
Accepted name: baicalin-β-D-glucuronidase
Reaction: baicalin + H2O = baicalein + D-glucuronate
Glossary: baicalin = 5,6,7-trihydroxyflavone-7-O-β-D-glucuronate = 5,6-dihydroxy-4-oxo-2-phenyl-4H-chromen-7-yl β-D-glucupyranosiduronic acid
baicalein = 5,6,7-trihydroxyflavone = 5,6,7-trihydroxy-2-phenyl-4H-chromen-4-one
wogonin = 5,7-dihydroxy-8-methoxyflavone = 5,7-dihydroxy-8-methoxy-2-phenyl-4H-chromen-4-one
oroxylin = 5,7-dihydroxy-6-methoxyflavone = 5,7-dihydroxy-6-methoxy-2-phenyl-4H-1-benzopyran-4-one
Other name(s): baicalinase
Systematic name: 5,6,7-trihydroxyflavone-7-O-β-D-glucupyranosiduronate glucuronosylhydrolase
Comments: The enzyme also hydrolyses wogonin 7-O-β-D-glucuronide and oroxylin 7-O-β-D-glucuronide with lower efficiency [4]. Neglegible activity with p-nitrophenyl-β-D-glucuronide [2].
References:
1.  Ikegami, F., Matsunae, K., Hisamitsu, M., Kurihara, T., Yamamoto, T. and Murakoshi, I. Purification and properties of a plant β-D-glucuronidase form Scutellaria root. Biol. Pharm. Bull. 18 (1995) 1531–1534. [PMID: 8593473]
2.  Zhang, C., Zhang, Y., Chen, J. and Liang, X. Purification and characterization of baicalin-β-D-glucuronidase hydrolyzing baicalin to baicalein from fresh roots of Scutellaria viscidula Bge. Proc. Biochem. 40 (2005) 1911–1915.
3.  Sasaki, K., Taura, F., Shoyama, Y. and Morimoto, S. Molecular characterization of a novel β-glucuronidase from Scutellaria baicalensis Georgi. J. Biol. Chem. 275 (2000) 27466–27472. [PMID: 10858442]
4.  Morimoto, S., Harioka, T. and Shoyama, Y. Purification and characterization of flavone-specific β-glucuronidase from callus cultures of Scutellaria baicalensis Georgi. Planta 195 (1995) 535–540.
[EC 3.2.1.167 created 2011]
 
 
EC 3.2.1.168     
Accepted name: hesperidin 6-O-α-L-rhamnosyl-β-D-glucosidase
Reaction: hesperidin + H2O = hesperetin + rutinose
Glossary: hesperetin = 5,7,3′-trihydroxy-4′-methoxyflavanone
hesperidin = hesperetin 7-(6-O-α-L-rhamnopyranosyl-β-D-glucopyranoside)
rutinose = 6-O-α-L-rhamnopyranosyl-D-glucose
Systematic name: hesperetin 7-(6-O-α-L-rhamnopyranosyl-β-D-glucopyranoside) 6-O-α-rhamnopyranosyl-β-glucohydrolase
Comments: The enzyme exhibits high specificity towards 7-O-linked flavonoid β-rutinosides.
References:
1.  Mazzaferro, L., Piñuel, L., Minig, M. and Breccia, J.D. Extracellular monoenzyme deglycosylation system of 7-O-linked flavonoid β-rutinosides and its disaccharide transglycosylation activity from Stilbella fimetaria. Arch. Microbiol. 192 (2010) 383–393. [PMID: 20358178]
2.  Mazzaferro, L., Piñuel, L., Minig, M. and Breccia, J.D. Erratum to: Extracellular monoenzyme deglycosylation system of 7-O-linked flavonoid β-rutinosides and its disaccharide transglycosylation activity from Stilbella fimetaria. Arch. Microbiol. 193 (2011) 461.
[EC 3.2.1.168 created 2011]
 
 
EC 3.2.1.169     
Accepted name: protein O-GlcNAcase
Reaction: (1) [protein]-3-O-(N-acetyl-β-D-glucosaminyl)-L-serine + H2O = [protein]-L-serine + N-acetyl-D-glucosamine
(2) [protein]-3-O-(N-acetyl-β-D-glucosaminyl)-L-theronine + H2O = [protein]-L-threonine + N-acetyl-D-glucosamine
Other name(s): OGA; glycoside hydrolase O-GlcNAcase; O-GlcNAcase; BtGH84; O-GlcNAc hydrolase
Systematic name: [protein]-3-O-(N-acetyl-β-D-glucosaminyl)-L-serine/threonine N-acetylglucosaminyl hydrolase
Comments: Within higher eukaryotes post-translational modification of protein serines/threonines with N-acetylglucosamine (O-GlcNAc) is dynamic, inducible and abundant, regulating many cellular processes by interfering with protein phosphorylation. EC 2.4.1.255 (protein O-GlcNAc transferase) transfers GlcNAc onto substrate proteins and EC 3.2.1.169 (protein O-GlcNAcase) cleaves GlcNAc from the modified proteins.
References:
1.  Gao, Y., Wells, L., Comer, F.I., Parker, G.J. and Hart, G.W. Dynamic O-glycosylation of nuclear and cytosolic proteins: cloning and characterization of a neutral, cytosolic β-N-acetylglucosaminidase from human brain. J. Biol. Chem. 276 (2001) 9838–9845. [PMID: 11148210]
2.  Wells, L., Gao, Y., Mahoney, J.A., Vosseller, K., Chen, C., Rosen, A. and Hart, G.W. Dynamic O-glycosylation of nuclear and cytosolic proteins: further characterization of the nucleocytoplasmic β-N-acetylglucosaminidase, O-GlcNAcase. J. Biol. Chem. 277 (2002) 1755–1761. [PMID: 11788610]
3.  Cetinbas, N., Macauley, M.S., Stubbs, K.A., Drapala, R. and Vocadlo, D.J. Identification of Asp174 and Asp175 as the key catalytic residues of human O-GlcNAcase by functional analysis of site-directed mutants. Biochemistry 45 (2006) 3835–3844. [PMID: 16533067]
4.  Dennis, R.J., Taylor, E.J., Macauley, M.S., Stubbs, K.A., Turkenburg, J.P., Hart, S.J., Black, G.N., Vocadlo, D.J. and Davies, G.J. Structure and mechanism of a bacterial β-glucosaminidase having O-GlcNAcase activity. Nat. Struct. Mol. Biol. 13 (2006) 365–371. [PMID: 16565725]
5.  Kim, E.J., Kang, D.O., Love, D.C. and Hanover, J.A. Enzymatic characterization of O-GlcNAcase isoforms using a fluorogenic GlcNAc substrate. Carbohydr. Res. 341 (2006) 971–982. [PMID: 16584714]
6.  Dong, D.L. and Hart, G.W. Purification and characterization of an O-GlcNAc selective N-acetyl-β-D-glucosaminidase from rat spleen cytosol. J. Biol. Chem. 269 (1994) 19321–19330. [PMID: 8034696]
[EC 3.2.1.169 created 2011]
 
 
EC 3.2.1.170     
Accepted name: mannosylglycerate hydrolase
Reaction: 2-O-(α-D-mannopyranosyl)-D-glycerate + H2O = D-mannopyranose + D-glycerate
Other name(s): MgH
Systematic name: 2-O-(α-D-mannopyranosyl)-D-glycerate D-mannohydrolase
Comments: The enzyme occurs in thermophilic bacteria and has been characterized in Thermus thermophilus and Rubrobacter radiotolerans. It also has been identified in the moss Selaginella moellendorffii.
References:
1.  Alarico, S., Empadinhas, N. and da Costa, M.S. A new bacterial hydrolase specific for the compatible solutes α-D-mannopyranosyl-(1→2)-D-glycerate and α-D-glucopyranosyl-(1→2)-D-glycerate. Enzyme Microb. Technol. 52 (2013) 77–83. [PMID: 23273275]
2.  Nobre, A., Empadinhas, N., Nobre, M.F., Lourenco, E.C., Maycock, C., Ventura, M.R., Mingote, A. and da Costa, M.S. The plant Selaginella moellendorffii possesses enzymes for synthesis and hydrolysis of the compatible solutes mannosylglycerate and glucosylglycerate. Planta 237 (2013) 891–901. [PMID: 23179444]
[EC 3.2.1.170 created 2011, modified 2018]
 
 
EC 3.2.1.171     
Accepted name: rhamnogalacturonan hydrolase
Reaction: Endohydrolysis of α-D-GalA-(1→2)-α-L-Rha glycosidic bond in the rhamnogalacturonan I backbone with initial inversion of anomeric configuration releasing oligosaccharides with β-D-GalA at the reducing end.
Other name(s): rhamnogalacturonase A; RGase A; RG-hydrolase
Systematic name: rhamnogalacturonan α-D-GalA-(1→2)-α-L-Rha hydrolase
Comments: The enzyme is part of the degradation system for rhamnogalacturonan I in Aspergillus aculeatus.
References:
1.  Petersen, T.N., Kauppinen, S. and Larsen, S. The crystal structure of rhamnogalacturonase A from Aspergillus aculeatus: a right-handed parallel β helix. Structure 5 (1997) 533–544. [PMID: 9115442]
2.  Kofod, L.V., Kauppinen, S., Christgau, S., Andersen, L.N., Heldt-Hansen, H.P., Dorreich, K. and Dalboge, H. Cloning and characterization of two structurally and functionally divergent rhamnogalacturonases from Aspergillus aculeatus. J. Biol. Chem. 269 (1994) 29182–29189. [PMID: 7961884]
3.  Azadi, P., O'Neill, M.A., Bergmann, C., Darvill, A.G. and Albersheim, P. The backbone of the pectic polysaccharide rhamnogalacturonan I is cleaved by an endohydrolase and an endolyase. Glycobiology 5 (1995) 783–789. [PMID: 8720076]
4.  Petersen, T.N., Christgau, S., Kofod, L.V., Kauppinen, S., Johnson, A.H. and Larsen, S. Crystallization and preliminary X-ray studies of rhamnogalacturonase A from Aspergillus aculeatus. Acta Crystallogr. D Biol. Crystallogr. 53 (1997) 105–107. [PMID: 15299976]
5.  Pitson, S.M., Mutter, M., van den Broek, L.A., Voragen, A.G. and Beldman, G. Stereochemical course of hydrolysis catalysed by α-L-rhamnosyl and α-D-galacturonosyl hydrolases from Aspergillus aculeatus. Biochem. Biophys. Res. Commun. 242 (1998) 552–559. [PMID: 9464254]
[EC 3.2.1.171 created 2011]
 
 
EC 3.2.1.172     
Accepted name: unsaturated rhamnogalacturonyl hydrolase
Reaction: 2-O-(4-deoxy-β-L-threo-hex-4-enopyranuronosyl)-α-L-rhamnopyranose + H2O = 5-dehydro-4-deoxy-D-glucuronate + L-rhamnopyranose
Glossary: 6-deoxy-2-O-(4-deoxy-β-L-threo-hex-4-enopyranuronosyl)-α-L-mannopyranose = 2-O-(4-deoxy-β-L-threo-hex-4-enopyranuronosyl)-α-L-rhamnopyranose
5-dehydro-4-deoxy-D-glucuronate = (4S,5R)-4,5-dihydroxy-2,6-dioxohexanoate
Other name(s): YteR; YesR
Systematic name: 2-O-(4-deoxy-β-L-threo-hex-4-enopyranuronosyl)-α-L-rhamnopyranose hydrolase
Comments: The enzyme is part of the degradation system for rhamnogalacturonan I in Bacillus subtilis strain 168.
References:
1.  Itoh, T., Ochiai, A., Mikami, B., Hashimoto, W. and Murata, K. A novel glycoside hydrolase family 105: the structure of family 105 unsaturated rhamnogalacturonyl hydrolase complexed with a disaccharide in comparison with family 88 enzyme complexed with the disaccharide. J. Mol. Biol. 360 (2006) 573–585. [PMID: 16781735]
2.  Zhang, R., Minh, T., Lezondra, L., Korolev, S., Moy, S.F., Collart, F. and Joachimiak, A. 1.6 Å crystal structure of YteR protein from Bacillus subtilis, a predicted lyase. Proteins 60 (2005) 561–565. [PMID: 15906318]
3.  Itoh, T., Ochiai, A., Mikami, B., Hashimoto, W. and Murata, K. Structure of unsaturated rhamnogalacturonyl hydrolase complexed with substrate. Biochem. Biophys. Res. Commun. 347 (2006) 1021–1029. [PMID: 16870154]
[EC 3.2.1.172 created 2011, modified 2012]
 
 
EC 3.2.1.173     
Accepted name: rhamnogalacturonan galacturonohydrolase
Reaction: Exohydrolysis of the α-D-GalA-(1→2)-α-L-Rha bond in rhamnogalacturonan oligosaccharides with initial inversion of configuration releasing D-galacturonic acid from the non-reducing end of rhamnogalacturonan oligosaccharides.
Other name(s): RG-galacturonohydrolase
Systematic name: rhamnogalacturonan oligosaccharide α-D-GalA-(1→2)-α-L-Rha galacturonohydrolase
Comments: The enzyme is part of the degradation system for rhamnogalacturonan I in Aspergillus aculeatus.
References:
1.  Mutter, M., Beldman, G., Pitson, S.M., Schols, H.A. and Voragen, A.G. Rhamnogalacturonan α-D-galactopyranosyluronohydrolase. An enzyme that specifically removes the terminal nonreducing galacturonosyl residue in rhamnogalacturonan regions of pectin. Plant Physiol. 117 (1998) 153–163. [PMID: 9576784]
[EC 3.2.1.173 created 2011]
 
 
EC 3.2.1.174     
Accepted name: rhamnogalacturonan rhamnohydrolase
Reaction: Exohydrolysis of the α-L-Rha-(1→4)-α-D-GalA bond in rhamnogalacturonan oligosaccharides with initial inversion of configuration releasing β-L-rhamnose from the non-reducing end of rhamnogalacturonan oligosaccharides.
Other name(s): RG-rhamnohydrolase; RG α-L-rhamnopyranohydrolase
Systematic name: rhamnogalacturonan oligosaccharide α-L-Rha-(1→4)-α-D-GalA rhamnohydrolase
Comments: The enzyme is part of the degradation system for rhamnogalacturonan I in Aspergillus aculeatus.
References:
1.  Pitson, S.M., Mutter, M., van den Broek, L.A., Voragen, A.G. and Beldman, G. Stereochemical course of hydrolysis catalysed by α-L-rhamnosyl and α-D-galacturonosyl hydrolases from Aspergillus aculeatus. Biochem. Biophys. Res. Commun. 242 (1998) 552–559. [PMID: 9464254]
2.  Mutter, M., Beldman, G., Schols, H.A. and Voragen, A.G. Rhamnogalacturonan α-L-rhamnopyranohydrolase. A novel enzyme specific for the terminal nonreducing rhamnosyl unit in rhamnogalacturonan regions of pectin. Plant Physiol. 106 (1994) 241–250. [PMID: 7972516]
[EC 3.2.1.174 created 2011]
 
 
EC 3.2.1.175     
Accepted name: β-D-glucopyranosyl abscisate β-glucosidase
Reaction: D-glucopyranosyl abscisate + H2O = D-glucose + abscisate
Other name(s): AtBG1; ABA-β-D-glucosidase; ABA-specific β-glucosidase; ABA-GE hydrolase; β-D-glucopyranosyl abscisate hydrolase
Systematic name: β-D-glucopyranosyl abscisate glucohydrolase
Comments: The enzyme hydrolzes the biologically inactive β-D-glucopyranosyl ester of abscisic acid to produce active abscisate. Abscisate is a phytohormone critical for plant growth, development and adaption to various stress conditions. The enzyme does not hydrolyse β-D-glucopyranosyl zeatin [1].
References:
1.  Lee, K.H., Piao, H.L., Kim, H.Y., Choi, S.M., Jiang, F., Hartung, W., Hwang, I., Kwak, J.M., Lee, I.J. and Hwang, I. Activation of glucosidase via stress-induced polymerization rapidly increases active pools of abscisic acid. Cell 126 (2006) 1109–1120. [PMID: 16990135]
2.  Kato-Noguchi, H. and Tanaka, Y. Effect of ABA-β-D-glucopyranosyl ester and activity of ABA-β-D-glucosidase in Arabidopsis thaliana. J. Plant Physiol. 165 (2008) 788–790. [PMID: 17923167]
3.  Dietz, K.J., Sauter, A., Wichert, K., Messdaghi, D. and Hartung, W. Extracellular β-glucosidase activity in barley involved in the hydrolysis of ABA glucose conjugate in leaves. J. Exp. Bot. 51 (2000) 937–944. [PMID: 10948220]
[EC 3.2.1.175 created 2011]
 
 
EC 3.2.1.176     
Accepted name: cellulose 1,4-β-cellobiosidase (reducing end)
Reaction: Hydrolysis of (1→4)-β-D-glucosidic linkages in cellulose and similar substrates, releasing cellobiose from the reducing ends of the chains.
Other name(s): CelS; CelSS; endoglucanase SS; cellulase SS; cellobiohydrolase CelS; Cel48A
Systematic name: 4-β-D-glucan cellobiohydrolase (reducing end)
Comments: Some exocellulases, most of which belong to the glycoside hydrolase family 48 (GH48, formerly known as cellulase family L), act at the reducing ends of cellulose and similar substrates. The CelS enzyme from Clostridium thermocellum is the most abundant subunit of the cellulosome formed by the organism. It liberates cellobiose units from the reducing end by hydrolysis of the glycosidic bond, employing an inverting reaction mechanism [2]. Different from EC 3.2.1.91, which attacks cellulose from the non-reducing end.
References:
1.  Barr, B.K., Hsieh, Y.L., Ganem, B. and Wilson, D.B. Identification of two functionally different classes of exocellulases. Biochemistry 35 (1996) 586–592. [PMID: 8555231]
2.  Saharay, M., Guo, H. and Smith, J.C. Catalytic mechanism of cellulose degradation by a cellobiohydrolase, CelS. PLoS One 5:e1294 (2010). [PMID: 20967294]
[EC 3.2.1.176 created 2011]
 
 
EC 3.2.1.177     
Accepted name: α-D-xyloside xylohydrolase
Reaction: Hydrolysis of terminal, non-reducing α-D-xylose residues with release of α-D-xylose.
Other name(s): α-xylosidase
Systematic name: α-D-xyloside xylohydrolase
Comments: The enzyme catalyses hydrolysis of a terminal, unsubstituted xyloside at the extreme reducing end of a xylogluco-oligosaccharide. Representative α-xylosidases from glycoside hydrolase family 31 utilize a two-step (double-displacement) mechanism involving a covalent glycosyl-enzyme intermediate, and retain the anomeric configuration of the product.
References:
1.  Moracci, M., Cobucci Ponzano, B., Trincone, A., Fusco, S., De Rosa, M., van Der Oost, J., Sensen, C.W., Charlebois, R.L. and Rossi, M. Identification and molecular characterization of the first α -xylosidase from an archaeon. J. Biol. Chem. 275 (2000) 22082–22089. [PMID: 10801892]
2.  Sampedro, J., Sieiro, C., Revilla, G., Gonzalez-Villa, T. and Zarra, I. Cloning and expression pattern of a gene encoding an α-xylosidase active against xyloglucan oligosaccharides from Arabidopsis. Plant Physiol. 126 (2001) 910–920. [PMID: 11402218]
3.  Crombie, H.J., Chengappa, S., Jarman, C., Sidebottom, C. and Reid, J.S. Molecular characterisation of a xyloglucan oligosaccharide-acting α-D-xylosidase from nasturtium (Tropaeolum majus L.) cotyledons that resembles plant ’apoplastic’ α-D-glucosidases. Planta 214 (2002) 406–413. [PMID: 11859845]
4.  Lovering, A.L., Lee, S.S., Kim, Y.W., Withers, S.G. and Strynadka, N.C. Mechanistic and structural analysis of a family 31 α-glycosidase and its glycosyl-enzyme intermediate. J. Biol. Chem. 280 (2005) 2105–2115. [PMID: 15501829]
5.  Iglesias, N., Abelenda, J.A., Rodino, M., Sampedro, J., Revilla, G. and Zarra, I. Apoplastic glycosidases active against xyloglucan oligosaccharides of Arabidopsis thaliana. Plant Cell Physiol. 47 (2006) 55–63. [PMID: 16267099]
6.  Okuyama, M., Kaneko, A., Mori, H., Chiba, S. and Kimura, A. Structural elements to convert Escherichia coli α-xylosidase (YicI) into α-glucosidase. FEBS Lett. 580 (2006) 2707–2711. [PMID: 16631751]
7.  Larsbrink, J., Izumi, A., Ibatullin, F., Nakhai, A., Gilbert, H.J., Davies, G.J. and Brumer, H. Structural and enzymatic characterisation of a glycoside hydrolase family 31 α-xylosidase from Cellvibrio japonicus involved in xyloglucan saccharification. Biochem. J. 436 (2011) 567–580. [PMID: 21426303]
[EC 3.2.1.177 created 2011]
 
 
EC 3.2.1.178     
Accepted name: β-porphyranase
Reaction: Hydrolysis of β-D-galactopyranose-(1→4)-α-L-galactopyranose-6-sulfate linkages in porphyran
Other name(s): porphyranase; PorA; PorB; endo-β-porphyranase
Systematic name: porphyran β-D-galactopyranose-(1→4)-α-L-galactopyranose-6-sulfate 4-glycanohydrolase
Comments: The backbone of porphyran consists largely (~70%) of (1→3)-linked β-D-galactopyranose followed by (1→4)-linked α-L-galactopyranose-6-sulfate [the other 30% are mostly agarobiose repeating units of (1→3)-linked β-D-galactopyranose followed by (1→4)-linked 3,6-anhydro-α-L-galactopyranose] [2]. This enzyme cleaves the (1→4) linkages between β-D-galactopyranose and α-L-galactopyranose-6-sulfate, forming mostly the disaccharide α-L-galactopyranose-6-sulfate-(1→3)-β-D-galactose, although some longer oligosaccharides of even number of residues are also observed. Since the enzyme is inactive on the non-sulfated agarose portion of the porphyran backbone, some agarose fragments are also included in the products [1]. Methylation of the D-galactose prevents the enzyme from Zobellia galactanivorans, but not that from Wenyingzhuangia fucanilytica, from binding at subsite -1 [2,3].
References:
1.  Hehemann, J.H., Correc, G., Barbeyron, T., Helbert, W., Czjzek, M. and Michel, G. Transfer of carbohydrate-active enzymes from marine bacteria to Japanese gut microbiota. Nature 464 (2010) 908–912. [PMID: 20376150]
2.  Correc, G., Hehemann, J.H., Czjzek, M. and Helbert, W. Structural analysis of the degradation products of porphyran digested by Zobellia galactanivorans β-porphyranase A. Carbohydrate Polymers 83 (2011) 277–283.
3.  Zhang, Y., Chang, Y., Shen, J., Mei, X. and Xue, C. Characterization of a novel porphyranase accommodating methyl-galactoses at its subsites. J. Agr. Food Chem. 68 (2020) 7032–7039. [PMID: 32520542]
[EC 3.2.1.178 created 2011]
 
 
EC 3.2.1.179     
Accepted name: gellan tetrasaccharide unsaturated glucuronosyl hydrolase
Reaction: β-D-4-deoxy-Δ4-GlcAp-(1→4)-β-D-Glcp-(1→4)-α-L-Rhap-(1→3)-D-Glcp + H2O = 5-dehydro-4-deoxy-D-glucuronate + β-D-Glcp-(1→4)-α-L-Rhap-(1→3)-D-Glcp
Glossary: 5-dehydro-4-deoxy-D-glucuronate = (4S,5R)-4,5-dihydroxy-2,6-dioxohexanoate
β-D-4-deoxy-Δ4-GlcAp-(1→3)-D-GalNAc = 3-(4-deoxy-β-D-gluc-4-enuronosyl)-N-acetyl-D-galactosamine = 3-(4-deoxy-α-L-threo-hex-4-enopyranosyluronic acid)-2-acetamido-2-deoxy-D-galactose
Other name(s): UGL (ambiguous); unsaturated glucuronyl hydrolase (ambiguous); gellan tetrasaccharide unsaturated glucuronyl hydrolase
Systematic name: β-D-4-deoxy-Δ4-GlcAp-(1→4)-β-D-Glcp-(1→4)-α-L-Rhap-(1→3)-D-Glcp β-D-4-deoxy-Δ4-GlcAp hydrolase
Comments: The enzyme releases 4-deoxy-4(5)-unsaturated D-glucuronic acid from oligosaccharides produced by polysaccharide lyases, e.g. the tetrasaccharide β-D-4-deoxy-Δ4-GlcAp-(1→4)-β-D-Glcp-(1→4)-α-L-Rhap-(1→3)-D-Glcp produced by EC 4.2.2.25, gellan lyase. The enzyme can also hydrolyse unsaturated chondroitin and hyaluronate disaccharides (β-D-4-deoxy-Δ4-GlcAp-(1→3)-D-GalNAc, β-D-4-deoxy-Δ4-GlcAp-(1→3)-D-GalNAc6S, β-D-4-deoxy-Δ4-GlcAp2S-(1→3)-D-GalNAc, β-D-4-deoxy-Δ4-GlcAp-(1→3)-D-GlcNAc), preferring the unsulfated disaccharides to the sulfated disaccharides.
References:
1.  Itoh, T., Akao, S., Hashimoto, W., Mikami, B. and Murata, K. Crystal structure of unsaturated glucuronyl hydrolase, responsible for the degradation of glycosaminoglycan, from Bacillus sp. GL1 at 1.8 Å resolution. J. Biol. Chem. 279 (2004) 31804–31812. [PMID: 15148314]
2.  Hashimoto, W., Kobayashi, E., Nankai, H., Sato, N., Miya, T., Kawai, S. and Murata, K. Unsaturated glucuronyl hydrolase of Bacillus sp. GL1: novel enzyme prerequisite for metabolism of unsaturated oligosaccharides produced by polysaccharide lyases. Arch. Biochem. Biophys. 368 (1999) 367–374. [PMID: 10441389]
3.  Itoh, T., Hashimoto, W., Mikami, B. and Murata, K. Substrate recognition by unsaturated glucuronyl hydrolase from Bacillus sp. GL1. Biochem. Biophys. Res. Commun. 344 (2006) 253–262. [PMID: 16630576]
[EC 3.2.1.179 created 2011, modified 2016]
 
 
EC 3.2.1.180     
Accepted name: unsaturated chondroitin disaccharide hydrolase
Reaction: β-D-4-deoxy-Δ4-GlcAp-(1→3)-β-D-GalNAc6S + H2O = 5-dehydro-4-deoxy-D-glucuronate + N-acetyl-β-D-galactosamine-6-O-sulfate
Glossary: 5-dehydro-4-deoxy-D-glucuronate = (4S,5R)-4,5-dihydroxy-2,6-dioxohexanoate
Other name(s): UGL (ambiguous); unsaturated glucuronyl hydrolase (ambiguous)
Systematic name: β-D-4-deoxy-Δ4-GlcAp-(1→3)-β-D-GalNAc6S hydrolase
Comments: The enzyme releases 4-deoxy-4,5-didehydro D-glucuronic acid or 4-deoxy-4,5-didehydro L-iduronic acid from chondroitin disaccharides, hyaluronan disaccharides and heparin disaccharides and cleaves both glycosidic (1→3) and (1→4) bonds. It prefers the sulfated disaccharides to the unsulfated disaccharides.
References:
1.  Maruyama, Y., Nakamichi, Y., Itoh, T., Mikami, B., Hashimoto, W. and Murata, K. Substrate specificity of streptococcal unsaturated glucuronyl hydrolases for sulfated glycosaminoglycan. J. Biol. Chem. 284 (2009) 18059–18069. [PMID: 19416976]
2.  Nakamichi, Y., Maruyama, Y., Mikami, B., Hashimoto, W. and Murata, K. Structural determinants in streptococcal unsaturated glucuronyl hydrolase for recognition of glycosaminoglycan sulfate groups. J. Biol. Chem. 286 (2011) 6262–6271. [PMID: 21147778]
[EC 3.2.1.180 created 2011]
 
 
EC 3.2.1.181     
Accepted name: galactan endo-β-1,3-galactanase
Reaction: The enzyme specifically hydrolyses β-1,3-galactan and β-1,3-galactooligosaccharides
Other name(s): endo-β-1,3-galactanase
Systematic name: arabinogalactan 3-β-D-galactanohydrolase
Comments: The enzyme from the fungus Flammulina velutipes (winter mushroom) hydrolyses the β(1→3) bonds found in type II plant arabinogalactans, which occur in cell walls of dicots and cereals. The enzyme is an endohydrolase, and requires at least 3 contiguous β-1,3-residues. cf. EC 3.2.1.89, arabinogalactan endo-β-1,4-galactanase and EC 3.2.1.145, galactan 1,3-β-galactosidase.
References:
1.  Kotake, T., Hirata, N., Degi, Y., Ishiguro, M., Kitazawa, K., Takata, R., Ichinose, H., Kaneko, S., Igarashi, K., Samejima, M. and Tsumuraya, Y. Endo-β-1,3-galactanase from winter mushroom Flammulina velutipes. J. Biol. Chem. 286 (2011) 27848–27854. [PMID: 21653698]
[EC 3.2.1.181 created 2012]
 
 
EC 3.2.1.182     
Accepted name: 4-hydroxy-7-methoxy-3-oxo-3,4-dihydro-2H-1,4-benzoxazin-2-yl glucoside β-D-glucosidase
Reaction: (1) (2R)-4-hydroxy-7-methoxy-3-oxo-3,4-dihydro-2H-1,4-benzoxazin-2-yl β-D-glucopyranoside + H2O = 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one + D-glucose
(2) (2R)-4-hydroxy-3-oxo-3,4-dihydro-2H-1,4-benzoxazin-2-yl β-D-glucopyranoside + H2O = 2,4-dihydroxy-2H-1,4-benzoxazin-3(4H)-one + D-glucose
Glossary: DIMBOA glucoside = (2R)-4-hydroxy-7-methoxy-3-oxo-3,4-dihydro-2H-1,4-benzoxazin-2-yl β-D-glucopyranoside
DIBOA glucoside = (2R)-4-hydroxy-3-oxo-3,4-dihydro-2H-1,4-benzoxazin-2-yl β-D-glucopyranoside
Other name(s): DIMBOAGlc hydrolase; DIMBOA glucosidase
Systematic name: (2R)-4-hydroxy-7-methoxy-3-oxo-3,4-dihydro-2H-1,4-benzoxazin-2-yl β-D-glucopyranoside β-D-glucosidase
Comments: The enzyme from Triticum aestivum (wheat) has a higher affinity for DIMBOA glucoside than DIBOA glucoside. With Secale cereale (rye) the preference is reversed.
References:
1.  Sue, M., Ishihara, A. and Iwamura, H. Purification and characterization of a hydroxamic acid glucoside β-glucosidase from wheat (Triticum aestivum L.) seedlings. Planta 210 (2000) 432–438. [PMID: 10750901]
2.  Sue, M., Ishihara, A. and Iwamura, H. Purification and characterization of a β-glucosidase from rye (Secale cereale L.) seedlings. Plant Sci. 155 (2000) 67–74. [PMID: 10773341]
3.  Czjzek, M., Cicek, M., Zamboni, V., Bevan, D.R., Henrissat, B. and Esen, A. The mechanism of substrate (aglycone) specificity in β-glucosidases is revealed by crystal structures of mutant maize β-glucosidase-DIMBOA, -DIMBOAGlc, and -dhurrin complexes. Proc. Natl. Acad. Sci. USA 97 (2000) 13555–13560. [PMID: 11106394]
4.  Nikus, J., Esen, A. and Jonsson, L.M.V. Cloning of a plastidic rye (Secale cereale) β-glucosidase cDNA and its expression in Escherichia coli. Physiol. Plantarum 118 (2003) 337–348.
5.  Sue, M., Yamazaki, K., Yajima, S., Nomura, T., Matsukawa, T., Iwamura, H. and Miyamoto, T. Molecular and structural characterization of hexameric β-D-glucosidases in wheat and rye. Plant Physiol. 141 (2006) 1237–1247. [PMID: 16751439]
6.  Sue, M., Nakamura, C., Miyamoto, T. and Yajima, S. Active-site architecture of benzoxazinone-glucoside β-D-glucosidases in Triticeae. Plant Sci. 180 (2011) 268–275. [PMID: 21421370]
[EC 3.2.1.182 created 2012]
 
 
EC 3.2.1.183     
Accepted name: UDP-N-acetylglucosamine 2-epimerase (hydrolysing)
Reaction: UDP-N-acetyl-α-D-glucosamine + H2O = N-acetyl-D-mannosamine + UDP
Other name(s): UDP-N-acetylglucosamine 2-epimerase (ambiguous); GNE (gene name); siaA (gene name); neuC (gene name)
Systematic name: UDP-N-acetyl-α-D-glucosamine hydrolase (2-epimerising)
Comments: The enzyme is found in mammalian liver, as well as in some pathogenic bacteria including Neisseria meningitidis and Staphylococcus aureus. It catalyses the first step of sialic acid (N-acetylneuraminic acid) biosynthesis. The initial product formed is the α anomer, which rapidly mutarotates to a mixture of anomers [2]. The mammalian enzyme is bifunctional and also catalyses EC 2.7.1.60, N-acetylmannosamine kinase. cf. EC 5.1.3.14, UDP-N-acetylglucosamine 2-epimerase (non-hydrolysing).
References:
1.  Stasche, R., Hinderlich, S., Weise, C., Effertz, K., Lucka, L., Moormann, P. and Reutter, W. A bifunctional enzyme catalyzes the first two steps in N-acetylneuraminic acid biosynthesis of rat liver. Molecular cloning and functional expression of UDP-N-acetyl-glucosamine 2-epimerase/N-acetylmannosamine kinase. J. Biol. Chem. 272 (1997) 24319–24324. [PMID: 9305888]
2.  Chou, W.K., Hinderlich, S., Reutter, W. and Tanner, M.E. Sialic acid biosynthesis: stereochemistry and mechanism of the reaction catalyzed by the mammalian UDP-N-acetylglucosamine 2-epimerase. J. Am. Chem. Soc. 125 (2003) 2455–2461. [PMID: 12603133]
3.  Blume, A., Ghaderi, D., Liebich, V., Hinderlich, S., Donner, P., Reutter, W. and Lucka, L. UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase, functionally expressed in and purified from Escherichia coli, yeast, and insect cells. Protein Expr. Purif. 35 (2004) 387–396. [PMID: 15135418]
4.  Murkin, A.S., Chou, W.K., Wakarchuk, W.W. and Tanner, M.E. Identification and mechanism of a bacterial hydrolyzing UDP-N-acetylglucosamine 2-epimerase. Biochemistry 43 (2004) 14290–14298. [PMID: 15518580]
[EC 3.2.1.183 created 2012]
 
 
EC 3.2.1.184     
Accepted name: UDP-N,N′-diacetylbacillosamine 2-epimerase (hydrolysing)
Reaction: UDP-N,N′-diacetylbacillosamine + H2O = UDP + 2,4-diacetamido-2,4,6-trideoxy-D-mannopyranose
Glossary: UDP-N,N′-diacetylbacillosamine = UDP-2,4-diacetamido-2,4,6-trideoxy-α-D-glucopyranose
Other name(s): UDP-Bac2Ac4Ac 2-epimerase; NeuC
Systematic name: UDP-N,N′-diacetylbacillosamine hydrolase (2-epimerising)
Comments: Requires Mg2+. Involved in biosynthesis of legionaminic acid, a nonulosonate derivative that is incorporated by some bacteria into assorted virulence-associated cell surface glycoconjugates. The initial product formed by the enzyme from Legionella pneumophila, which incorporates legionaminic acid into the O-antigen moiety of its lipopolysaccharide, is 2,4-diacetamido-2,4,6-trideoxy-α-D-mannopyranose, which rapidly mutarotates to a mixture of anomers [1]. The enzyme from Campylobacter jejuni, which incorporates legionaminic acid into flagellin, prefers GDP-N,N′-diacetylbacillosamine [2].
References:
1.  Glaze, P.A., Watson, D.C., Young, N.M. and Tanner, M.E. Biosynthesis of CMP-N,N′-diacetyllegionaminic acid from UDP-N,N′-diacetylbacillosamine in Legionella pneumophila. Biochemistry 47 (2008) 3272–3282. [PMID: 18275154]
2.  Schoenhofen, I.C., Vinogradov, E., Whitfield, D.M., Brisson, J.R. and Logan, S.M. The CMP-legionaminic acid pathway in Campylobacter: biosynthesis involving novel GDP-linked precursors. Glycobiology 19 (2009) 715–725. [PMID: 19282391]
[EC 3.2.1.184 created 2012]
 
 
EC 3.2.1.185     
Accepted name: non-reducing end β-L-arabinofuranosidase
Reaction: β-L-arabinofuranosyl-(1→2)-β-L-arabinofuranose + H2O = 2 β-L-arabinofuranose
Other name(s): HypBA1
Systematic name: β-L-arabinofuranoside non-reducing end β-L-arabinofuranosidase
Comments: The enzyme, which was identified in the bacterium Bifidobacterium longum JCM1217, removes the β-L-arabinofuranose residue from the non-reducing end of multiple substrates, including β-L-arabinofuranosyl-hydroxyproline (Ara-Hyp), Ara2-Hyp, Ara3-Hyp, and β-L-arabinofuranosyl-(1→2)-1-O-methyl-β-L-arabinofuranose.In the presence of 1-alkanols, the enzyme demonstrates transglycosylation activity, retaining the anomeric configuration of the arabinofuranose residue. cf. EC 3.2.1.55, non-reducing end α-L-arabinofuranosidase
References:
1.  Fujita, K., Takashi, Y., Obuchi, E., Kitahara, K. and Suganuma, T. Characterization of a novel β-L-arabinofuranosidase in Bifidobacterium longum: functional elucidation of a DUF1680 protein family member. J. Biol. Chem. 289 (2014) 5240–5249. [PMID: 24385433]
[EC 3.2.1.185 created 2013]
 
 
EC 3.2.1.186     
Accepted name: protodioscin 26-O-β-D-glucosidase
Reaction: protodioscin + H2O = 26-deglucoprotodioscin + D-glucose
Other name(s): F26G; torvosidase; CSF26G1; furostanol glycoside 26-O-β-D-glucosidase; furostanol 26-O-β-D-glucoside glucohydrolase
Systematic name: protodioscin glucohydrolase
Comments: The enzyme has been characterized from the plants Cheilocostus speciosus and Solanum torvum. It also hydrolyses the 26-β-D-glucose group from related steroid glucosides such as protogracillin, torvoside A and torvoside H.
References:
1.  Inoue, K. and Ebizuka, Y. Purification and characterization of furostanol glycoside 26-O-β-glucosidase from Costus speciosus rhizomes. FEBS Lett. 378 (1996) 157–160. [PMID: 8549824]
2.  Arthan, D., Kittakoop, P., Esen, A. and Svasti, J. Furostanol glycoside 26-O-β-glucosidase from the leaves of Solanum torvum. Phytochemistry 67 (2006) 27–33. [PMID: 16289258]
[EC 3.2.1.186 created 2013]
 
 
EC 3.2.1.187     
Accepted name: (Ara-f)3-Hyp β-L-arabinobiosidase
Reaction: 4-O-(β-L-arabinofuranosyl-(1→2)-β-L-arabinofuranosyl-(1→2)-β-L-arabinofuranosyl)-(2S,4S)-4-hydroxyproline + H2O = 4-O-(β-L-arabinofuranosyl)-(2S,4S)-4-hydroxyproline + β-L-arabinofuranosyl-(1→2)-β-L-arabinofuranose
Glossary: 4-O-(β-L-arabinofuranosyl-(1→2)-β-L-arabinofuranosyl-(1→2)-β-L-arabinofuranosyl)-(2S,4S)-4-hydroxyproline = (Ara-f)3-Hyp
Other name(s): hypBA2 (gene name); β-L-arabinobiosidase
Systematic name: 4-O-(β-L-arabinofuranosyl-(1→2)-β-L-arabinofuranosyl-(1→2)-β-L-arabinofuranosyl)-(2S,4S)-4-hydroxyproline β-L-arabinofuranosyl-(1→2)-β-L-arabinofuranose hydrolase
Comments: The enzyme, which was identified in the bacterium Bifidobacterium longum JCM1217, is specific for (Ara-f)3-Hyp, a sugar chain found in hydroxyproline-rich glyoproteins such as extensin and lectin. The enzyme was not able to accept (Ara-f)2-Hyp or (Ara-f)4-Hyp as substrates. In the presence of 1-alkanols, the enzyme demonstrates transglycosylation activity, retaining the anomeric configuration of the arabinofuranose residue.
References:
1.  Fujita, K., Sakamoto, S., Ono, Y., Wakao, M., Suda, Y., Kitahara, K. and Suganuma, T. Molecular cloning and characterization of a β-L-Arabinobiosidase in Bifidobacterium longum that belongs to a novel glycoside hydrolase family. J. Biol. Chem. 286 (2011) 5143–5150. [PMID: 21149454]
[EC 3.2.1.187 created 2013]
 
 
EC 3.2.1.188     
Accepted name: avenacosidase
Reaction: avenacoside B + H2O = 26-desgluco-avenacoside B + D-glucose
Glossary: avenacoside B = (22S,25S)-3β-{β-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl-(1→4)-[α-L-rhamnopyranosyl-(1→2)]-β-D-glucopyranosyloxy}-26-(β-D-glucopyranosyloxy)-22,25-epoxyfurost-5-ene
26-desgluco-avenacoside B = (22S,25S)-3β-{β-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl-(1→4)-[α-L-rhamnopyranosyl-(1→2)]-β-D-glucopyranosyloxy}-22,25-epoxyfurost-5-en-26-ol
Other name(s): As-P60
Systematic name: avenacoside B 26-β-D-glucohydrolase
Comments: Isolated from oat (Avena sativa) seedlings. The product acts as a defense system against fungal infection. Also acts on avenacoside A.
References:
1.  Gus-Mayer, S., Brunner, H., Schneider-Poetsch, H.A. and Rudiger, W. Avenacosidase from oat: purification, sequence analysis and biochemical characterization of a new member of the BGA family of β-glucosidases. Plant Mol. Biol. 26 (1994) 909–921. [PMID: 8000004]
2.  Gus-Mayer, S., Brunner, H., Schneider-Poetsch, H.A., Lottspeich, F., Eckerskorn, C., Grimm, R. and Rudiger, W. The amino acid sequence previously attributed to a protein kinase or a TCP1-related molecular chaperone and co-purified with phytochrome is a β-glucosidase. FEBS Lett. 347 (1994) 51–54. [PMID: 8013661]
[EC 3.2.1.188 created 2013]
 
 
EC 3.2.1.189     
Accepted name: dioscin glycosidase (diosgenin-forming)
Reaction: 3-O-[α-L-Rha-(1→4)-[α-L-Rha-(1→2)]-β-D-Glc]diosgenin + 3 H2O = D-glucose + 2 L-rhamnose + diosgenin
Glossary: 3-O-[α-L-Rha-(1→4)-[α-L-Rha-(1→2)]-β-D-Glc]diosgenin = (3β,25R)-spirost-5-en-3-yl 6-deoxy-α-L-mannopyranosyl-(1→2)-[6-deoxy-α-L-mannopyranosyl-(1→4)]-β-D-glucopyranoside = dioscin
diosgenin = (3β,25R)-spirost-5-en-3-ol
Other name(s): dioscin glycosidase (aglycone-forming)
Systematic name: 3-O-[α-L-Rha-(1→4)-[α-L-Rha-(1→2)]-β-D-Glc]diosgenin hydrolase (diosgenin-forming)
Comments: The enzyme is involved in degradation of the steroid saponin dioscin by some fungi of the Absidia genus. The enzyme can also hydrolyse 3-O-[α-L-Ara-(1→4)-[α-L-Rha-(1→2)]-β-D-Glc]diosgenin into diosgenin and free sugars as the final products. cf. EC 3.2.1.190, dioscin glycosidase (3-O-β-D-Glc-diosgenin-forming).
References:
1.  Fu, Y., Yu, H., Tang, S.H., Hu, X., Wang, Y., Liu, B., Yu, C. and Jin, F. New dioscin-glycosidase hydrolyzing multi-glycosides of dioscin from Absidia strain. J. Microbiol. Biotechnol. 20 (2010) 1011–1017. [PMID: 20622501]
[EC 3.2.1.189 created 2013]
 
 
EC 3.2.1.190     
Accepted name: dioscin glycosidase (3-O-β-D-Glc-diosgenin-forming)
Reaction: 3-O-[α-L-Rha-(1→4)-[α-L-Rha-(1→2)]-β-D-Glc]diosgenin + 2 H2O = 2 L-rhamnopyranose + diosgenin 3-O-β-D-glucopyranoside
Glossary: 3-O-[α-L-Rha-(1→4)-[α-L-Rha-(1→2)]-β-D-Glc]diosgenin = (3β,25R)-spirost-5-en-3-yl 6-deoxy-α-L-mannopyranosyl-(1→2)-[6-deoxy-α-L-mannopyranosyl-(1→4)]-β-D-glucopyranoside = dioscin
diosgenin = (3β,25R)-spirost-5-en-3-ol
Other name(s): dioscin-α-L-rhamnosidase
Systematic name: 3-O-[α-L-Rha-(1→4)-[α-L-Rha-(1→2)]-β-D-Glc]diosgenin (3-O-β-D-Glc-diosgenin-forming)
Comments: The enzyme is involved in the hydrolysis of the steroid saponin dioscin by the digestive system of Sus scrofa (pig). cf. EC 3.2.1.189, dioscin glycosidase (diosgenin-forming).
References:
1.  Qian, S., Yu, H., Zhang, C., Lu, M., Wang, H. and Jin, F. Purification and characterization of dioscin-α-L-rhamnosidase from pig liver. Chem Pharm Bull (Tokyo) 53 (2005) 911–914. [PMID: 16079518]
[EC 3.2.1.190 created 2013]
 
 
EC 3.2.1.191     
Accepted name: ginsenosidase type III
Reaction: a protopanaxadiol-type ginsenoside with two glucosyl residues at position 3 + 2 H2O = a protopanaxadiol-type ginsenoside with no glycosidic modification at position 3 + 2 D-glucopyranose (overall reaction)
(1a) a protopanaxadiol-type ginsenoside with two glucosyl residues at position 3 + H2O a protopanaxadiol-type ginsenoside with one glucosyl residue at position 3 + D-glucopyranose
(1b) a protopanaxadiol-type ginsenoside with one glucosyl residue at position 3 + H2O = a protopanaxadiol-type ginsenoside with no glycosidic modification at position 3 + D-glucopyranose
Glossary: ginsenoside Rb1 = 3β-[β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyloxy]-20-[β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyloxy]dammar-24-en-12β-ol
gypenoside XVII = 3β-(β-D-glucopyranosyloxy)-20-[β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyloxy]dammar-24-en-12β-ol
gypenoside LXXV = 20-[β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyloxy]dammar-24-ene-3β,12β-diol
Systematic name: protopanaxadiol-type ginsenoside 3-β-D-hydrolase
Comments: Ginsenosidase type III catalyses the sequential hydrolysis of the 3-O-β-D-(1→2)-glucopyranosyl bond followed by hydrolysis of the 3-O-β-D-glucopyranosyl bond of protopanaxadiol ginsenosides. When acting for example on ginsenoside Rb1 the enzyme first generates ginsenoside XVII, and subsequently ginsenoside LXXV.
References:
1.  Jin, X.F., Yu, H.S., Wang, D.M., Liu, T.Q., Liu, C.Y., An, D.S., Im, W.T., Kim, S.G. and Jin, F.X. Kinetics of a cloned special ginsenosidase hydrolyzing 3-O-glucoside of multi-protopanaxadiol-type ginsenosides, named ginsenosidase type III. J. Microbiol. Biotechnol. 22 (2012) 343–351. [PMID: 22450790]
2.  An, D.S., Cui, C.H., Lee, H.G., Wang, L., Kim, S.C., Lee, S.T., Jin, F., Yu, H., Chin, Y.W., Lee, H.K., Im, W.T. and Kim, S.G. Identification and characterization of a novel Terrabacter ginsenosidimutans sp. nov. β-glucosidase that transforms ginsenoside Rb1 into the rare gypenosides XVII and LXXV. Appl. Environ. Microbiol. 76 (2010) 5827–5836. [PMID: 20622122]
3.  Hong, H., Cui, C.H., Kim, J.K., Jin, F.X., Kim, S.C. and Im, W.T. Enzymatic Biotransformation of Ginsenoside Rb1 and Gypenoside XVII into Ginsenosides Rd and F2 by Recombinant β-glucosidase from Flavobacterium johnsoniae. J Ginseng Res 36 (2012) 418–424. [PMID: 23717145]
[EC 3.2.1.191 created 2014]
 
 
EC 3.2.1.192     
Accepted name: ginsenoside Rb1 β-glucosidase
Reaction: ginsenoside Rb1 + 2 H2O = ginsenoside Rg3 + 2 D-glucopyranose (overall reaction)
(1a) ginsenoside Rb1 + H2O = ginsenoside Rd + D-glucopyranose
(1b) ginsenoside Rd + H2O = ginsenoside Rg3 + D-glucopyranose
Glossary: ginsenoside Rb1 = 3β-[β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyloxy]-20-[β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyloxy]dammar-24-en-12β-ol
ginsenoside Rd = 3β-[β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyloxy]-20-(β-D-glucopyranosyloxy)dammar-24-en-12β-ol
ginsenoside F2 = 3β,20-bis(β-D-glucopyranosyloxy)dammar-24-en-12β-ol
Systematic name: ginsenoside Rb1 glucohydrolase
Comments: Ginsenosidases catalyse the hydrolysis of glycosyl moieties attached to the C-3, C-6 or C-20 position of ginsenosides. They are specific with respect to the nature of the glycosidic linkage, the position and the order in which the linkages are cleaved. Ginsenoside Rb1 β-glucosidase specifically and sequentially hydrolyses the 20-[β-D-glucopyranosyl-(1→6)-β-D glucopyranosyloxy] residues attached to position 20 by first hydrolysing the (1→6)-glucosidic bond to generate ginsenoside Rd as an intermediate, followed by hydrolysis of the remaining 20-O-β-D-glucosidic bond.
References:
1.  Yan, Q., Zhou, W., Li, X., Feng, M. and Zhou, P. Purification method improvement and characterization of a novel ginsenoside-hydrolyzing β-glucosidase from Paecilomyces Bainier sp. 229. Biosci. Biotechnol. Biochem. 72 (2008) 352–359. [PMID: 18256474]
[EC 3.2.1.192 created 2014]
 
 
EC 3.2.1.193     
Accepted name: ginsenosidase type I
Reaction: (1) a protopanaxadiol-type ginsenoside with two glucosyl residues at position 3 + H2O = a protopanaxadiol-type ginsenoside with one glucosyl residue at position 3 + D-glucopyranose
(2) a protopanaxadiol-type ginsenoside with one glucosyl residue at position 3 + H2O = a protopanaxadiol-type ginsenoside with no glycosidic modifications at position 3 + D-glucopyranose
(3) a protopanaxadiol-type ginsenoside with two glycosyl residues at position 20 + H2O = a protopanaxadiol-type ginsenoside with a single glucosyl residue at position 20 + a monosaccharide
Glossary: ginsenoside Rb1 = 3β-[β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyloxy]-20-[β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyloxy]dammar-24-en-12β-ol
ginsenoside Rb2 = 3β-[β-D-glucopyranosyl-(1→2)-β-D glucopyranosyloxy]-20-[α-L-arabinopyranosyl-(1→6)-β-D glucopyranosyloxy]dammar-24-en-12β-ol
ginsenoside Rb3 = 3β-[β-D-glucopyranosyl-(1→2)-β-D glucopyranosyloxy]-20-[β-D-xylopyranosyl-(1→6)-β-D glucopyranosyloxy]dammar-24-en-12β-ol
ginsenoside Rc = 3β-[β-D-glucopyranosyl-(1→2)-β-D glucopyranosyloxy]-20-[α-L-arabinofuranosyl-(1→6)-β-D glucopyranosyloxy]dammar-24-en-12β-ol
ginsenoside Rd = 3β-[β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyloxy]-20-(β-D-glucopyranosyloxy)dammar-24-en-12β-ol
ginsenoside F2 = 3β,20-bis(β-D-glucopyranosyloxy)dammar-24-en-12β-ol
ginsenoside C-K = 20β-(β-D-glucopyranosyloxy)dammar-24-ene-3β,12β-diol
ginsenoside Rh2 = 3β-(β-D-glucopyranosyloxy)dammar-24-ene-12β,20-diol
Systematic name: ginsenoside glucohydrolase
Comments: Ginsenosidase type I is slightly activated by Mg2+ or Ca2+ [1]. The enzyme hydrolyses the 3-O-β-D-(1→2)-glucosidic bond, the 3-O-β-D-glucopyranosyl bond and the 20-O-β-D-(1→6)-glycosidic bond of protopanaxadiol-type ginsenosides. It usually leaves a single glucosyl residue attached at position 20 and one or no glucosyl residues at position 3. Starting with a ginsenoside that is glycosylated at both positions (e.g. ginsenoside Rb1, Rb2, Rb3, Rc or Rd), the most common products are ginsenoside F2 and ginsenoside C-K, with low amounts of ginsenoside Rh2.
References:
1.  Yu, H., Zhang, C., Lu, M., Sun, F., Fu, Y. and Jin, F. Purification and characterization of new special ginsenosidase hydrolyzing multi-glycisides of protopanaxadiol ginsenosides, ginsenosidase type I. Chem Pharm Bull (Tokyo) 55 (2007) 231–235. [PMID: 17268094]
[EC 3.2.1.193 created 2014]
 
 
EC 3.2.1.194     
Accepted name: ginsenosidase type IV
Reaction: a protopanaxatriol-type ginsenoside with two glycosyl residues at position 6 + 2 H2O = a protopanaxatriol-type ginsenoside with no glycosidic modification at position 6 + D-glucopyranose + a monosaccharide (overall reaction)
(1a) a protopanaxatriol-type ginsenoside with two glycosyl residues at position 6 + H2O = a protopanaxatriol-type ginsenoside with a single glucosyl at position 6 + a monosaccharide
(1b) a protopanaxatriol-type ginsenoside with a single glucosyl at position 6 + H2O = a protopanaxatriol-type ginsenoside with no glycosidic modification at position 6 + D-glucopyranose
Glossary: ginsenoside Re = 20-(β-D-glucopyranosyl)oxy-6α-[α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyloxy]dammar-24-en-3β,12β-diol
ginsenoside Rg1 = 6α,20-bis(β-D-glucopyranosyl)oxy-dammar-24-en-3β,12β-diol
ginsenoside F1 = 20-(β-D-glucopyranosyloxy)dammar-24-en-3β,6α,12β-triol
Systematic name: protopanaxatriol-type ginsenoside 6-β-D-glucohydrolase
Comments: Ginsenosidase type IV catalyses the sequential hydrolysis of the 6-O-β-D-(1→2)-glycosidic bond or the 6-O-α-D-(1→2)-glycosidic bond in protopanaxatriol-type ginsenosides with a disacchride attached to the C6 position, followed by the hydrolysis of the remaining 6-O-β-D-glycosidic bond (e.g. ginsenoside Re → ginsenoside Rg1 → ginsenoside F1).
References:
1.  Wang, D.M., Yu, H.S., Song, J.G., Xu, Y.F., Liu, C.Y. and Jin, F.X. A novel ginsenosidase from an Aspergillus strain hydrolyzing 6-O-multi-glycosides of protopanaxatriol-type ginsenosides, named ginsenosidase type IV. J. Microbiol. Biotechnol. 21 (2011) 1057–1063. [PMID: 22031031]
2.  Wang, D, Yu, H., Song, J., Xu, Y., Jin, F. Enzyme kinetics of ginsenosidase type IV hydrolyzing 6-O-multi-glycosides of protopanaxatriol type ginsenosides. Process Biochem. 47 (2012) 133–138.
[EC 3.2.1.194 created 2014]
 
 
EC 3.2.1.195     
Accepted name: 20-O-multi-glycoside ginsenosidase
Reaction: a protopanaxadiol-type ginsenoside with two glycosyl residues at position 20 + H2O = a protopanaxadiol-type ginsenoside with a single glucosyl residue at position 20 + a monosaccharide
Glossary: ginsenoside Rb1 = 3β-[β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyloxy]-20-[β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyloxy]dammar-24-en-12β-ol
ginsenoside Rb2 = 3β-[β-D-glucopyranosyl-(1→2)-β-D glucopyranosyloxy]-20-[α-L-arabinopyranosyl-(1→6)-β-D glucopyranosyloxy]dammar-24-en-12β-ol
ginsenoside Rb3 = 3β-[β-D-glucopyranosyl-(1→2)-β-D glucopyranosyloxy]-20-[β-D-xylopyranosyl-(1→6)-β-D glucopyranosyloxy]dammar-24-en-12β-ol
ginsenoside Rc = 3β-[β-D-glucopyranosyl-(1→2)-β-D glucopyranosyloxy]-20-[α-L-arabinofuranosyl-(1→6)-β-D glucopyranosyloxy]dammar-24-en-12β-ol
ginsenoside Rd = 3β-[β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyloxy]-20-(β-D-glucopyranosyloxy)dammar-24-en-12β-ol
ginsenoside Rg3 = 3β-[β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyloxy]-20-(β-D-glucopyranosyloxy)dammar-24-ene-12β,20-diol
Other name(s): ginsenosidase type II (erroneous)
Systematic name: protopanaxadiol-type ginsenoside 20-β-D-glucohydrolase
Comments: The 20-O-multi-glycoside ginsenosidase catalyses the hydrolysis of the 20-O-α-(1→6)-glycosidic bond and the 20-O-β-(1→6)-glycosidic bond of protopanaxadiol-type ginsenosides. The enzyme usually leaves a single glucosyl residue attached at position 20, although it can cleave the remaining glucosyl residue with a lower efficiency. Starting with a ginsenoside that is glycosylated at positions 3 and 20, such as ginsenosides Rb1, Rb2, Rb3 and Rc, the most common product is ginsenoside Rd, with a low amount of ginsenoside Rg3 also formed.
References:
1.  Yu, H., Liu, Q., Zhang, C., Lu, M., Fu, Y., Im, W.-T., Lee, S.-T. and Jin, F. A new ginsenosidase from Aspergillus strain hydrolyzing 20-O-multi-glycoside of PPD ginsenoside. Process Biochem. 44 (2009) 772–775.
[EC 3.2.1.195 created 2014]
 
 
EC 3.2.1.196     
Accepted name: limit dextrin α-1,6-maltotetraose-hydrolase
Reaction: Hydrolysis of (1→6)-α-D-glucosidic linkages to branches with degrees of polymerization of three or four glucose residues in limit dextrin.
Other name(s): glgX (gene name); glycogen debranching enzyme (ambiguous)
Systematic name: glycogen phosphorylase-limit dextrin maltotetraose-hydrolase
Comments: This bacterial enzyme catalyses a reaction similar to EC 3.2.1.33, amylo-α-1,6-glucosidase (one of the activities of the eukaryotic glycogen debranching enzyme). However, while EC 3.2.1.33 removes single glucose residues linked by 1,6-α-linkage, and thus requires the additional activity of 4-α-glucanotransferase (EC 2.4.1.25) to act on limit dextrins formed by glycogen phosphorylase (EC 2.4.1.1), this enzyme removes maltotriose and maltotetraose chains that are attached by 1,6-α-linkage to the limit dextrin main chain, generating a debranched limit dextrin without a need for another enzyme.
References:
1.  Jeanningros, R., Creuzet-Sigal, N., Frixon, C. and Cattaneo, J. Purification and properties of a debranching enzyme from Escherichia coli. Biochim. Biophys. Acta 438 (1976) 186–199. [PMID: 779849]
2.  Dauvillee, D., Kinderf, I.S., Li, Z., Kosar-Hashemi, B., Samuel, M.S., Rampling, L., Ball, S. and Morell, M.K. Role of the Escherichia coli glgX gene in glycogen metabolism. J. Bacteriol. 187 (2005) 1465–1473. [PMID: 15687211]
3.  Song, H.N., Jung, T.Y., Park, J.T., Park, B.C., Myung, P.K., Boos, W., Woo, E.J. and Park, K.H. Structural rationale for the short branched substrate specificity of the glycogen debranching enzyme GlgX. Proteins 78 (2010) 1847–1855. [PMID: 20187119]
[EC 3.2.1.196 created 2016]
 
 
EC 3.2.1.197     
Accepted name: β-1,2-mannosidase
Reaction: β-D-mannopyranosyl-(1→2)-β-D-mannopyranosyl-(1→2)-D-mannopyranose + H2O = β-D-mannopyranosyl-(1→2)-D-mannopyranose + α-D-mannopyranose
Systematic name: β-1,2-D-mannoside mannohydrolase
Comments: The enzyme, characterized from multiple bacterial species, catalyses the hydrolysis of terminal, non-reducing D-mannose residues from β-1,2-mannotriose and β-1,2-mannobiose. The mechanism involves anomeric inversion, resulting in the release of α-D-mannopyranose. Activity with β-1,2-mannotriose or higher oligosaccharides is higher than that with β-1,2-mannobiose.
References:
1.  Cuskin, F., Basle, A., Ladeveze, S., Day, A.M., Gilbert, H.J., Davies, G.J., Potocki-Veronese, G. and Lowe, E.C. The GH130 family of mannoside phosphorylases contains glycoside hydrolases that target β-1,2-mannosidic linkages in Candida mannan. J. Biol. Chem. 290 (2015) 25023–25033. [PMID: 26286752]
2.  Nihira, T., Chiku, K., Suzuki, E., Nishimoto, M., Fushinobu, S., Kitaoka, M., Ohtsubo, K. and Nakai, H. An inverting β-1,2-mannosidase belonging to glycoside hydrolase family 130 from Dyadobacter fermentans. FEBS Lett. 589 (2015) 3604–3610. [PMID: 26476324]
[EC 3.2.1.197 created 2016]
 
 
EC 3.2.1.198     
Accepted name: α-mannan endo-1,2-α-mannanase
Reaction: Hydrolysis of the terminal α-D-mannosyl-(1→3)-α-D-mannose disaccharide from α-D-mannosyl-(1→3)-α-D-mannosyl-(1→2)-α-D-mannosyl-(1→2)-α-D-mannosyl side chains in fungal cell wall α-mannans.
Systematic name: α-mannan 1,2-[α-D-mannosyl-(1→3)-α-D-mannose] hydrolase
Comments: The enzyme, characterized from the gut bacteria Bacteroides thetaiotaomicron and Bacteroides xylanisolvens, can also catalyse the reaction of EC 3.2.1.130, glycoprotein endo-α-1,2-mannosidase.
References:
1.  Hakki, Z., Thompson, A.J., Bellmaine, S., Speciale, G., Davies, G.J. and Williams, S.J. Structural and kinetic dissection of the endo-α-1,2-mannanase activity of bacterial GH99 glycoside hydrolases from Bacteroides spp. Chemistry 21 (2015) 1966–1977. [PMID: 25487964]
2.  Cuskin, F., Lowe, E.C., Temple, M.J., Zhu, Y., Cameron, E.A., Pudlo, N.A., Porter, N.T., Urs, K., Thompson, A.J., Cartmell, A., Rogowski, A., Hamilton, B.S., Chen, R., Tolbert, T.J., Piens, K., Bracke, D., Vervecken, W., Hakki, Z., Speciale, G., Munoz-Munoz, J.L., Day, A., Pena, M.J., McLean, R., Suits, M.D., Boraston, A.B., Atherly, T., Ziemer, C.J., Williams, S.J., Davies, G.J., Abbott, D.W., Martens, E.C. and Gilbert, H.J. Human gut Bacteroidetes can utilize yeast mannan through a selfish mechanism. Nature 517 (2015) 165–169. [PMID: 25567280]
[EC 3.2.1.198 created 2016]
 
 
EC 3.2.1.199     
Accepted name: sulfoquinovosidase
Reaction: an 6-sulfo-α-D-quinovosyl diacylglycerol + H2O = 6-sulfo-D-quinovose + a 1,2-diacylglycerol
Other name(s): yihQ (gene name)
Systematic name: 6-sulfo-α-D-quinovosyl diacylglycerol 6-sulfo-D-quinovohydrolase
Comments: The enzyme, characterized from the bacteria Escherichia coli and Pseudomonas putida, hydrolyses terminal non-reducing α-sulfoquinovoside residues in α-sulfoquinovosyl diacylglycerides and α-sulfoquinovosyl glycerol.
References:
1.  Shibuya, I. and Benson, A. A. Hydrolysis of α-sulphoquinovosides by β-galactosidase. Nature 192 (1961) 1186–1187.
2.  Speciale, G., Jin, Y., Davies, G.J., Williams, S.J. and Goddard-Borger, E.D. YihQ is a sulfoquinovosidase that cleaves sulfoquinovosyl diacylglyceride sulfolipids. LID - 10.1038/nchembio.2023 [doi. Nat. Chem. Biol. (2016) . [PMID: 26878550]
[EC 3.2.1.199 created 2016]
 
 
EC 3.2.1.200     
Accepted name: exo-chitinase (non-reducing end)
Reaction: Hydrolysis of N,N′-diacetylchitobiose from the non-reducing end of chitin and chitodextrins.
Other name(s): chiB (gene name)
Systematic name: (1→4)-2-acetamido-2-deoxy-β-D-glucan diacetylchitobiohydrolase (non-reducing end)
Comments: The enzyme hydrolyses the second glycosidic (1→4) linkage from non-reducing ends of chitin and chitodextrin molecules, liberating N,N′-diacetylchitobiose disaccharides. cf. EC 3.2.1.201, exo-chitinase (reducing end).
References:
1.  Tanaka, T., Fukui, T. and Imanaka, T. Different cleavage specificities of the dual catalytic domains in chitinase from the hyperthermophilic archaeon Thermococcus kodakaraensis KOD1. J. Biol. Chem. 276 (2001) 35629–35635. [PMID: 11468293]
2.  Hult, E.L., Katouno, F., Uchiyama, T., Watanabe, T. and Sugiyama, J. Molecular directionality in crystalline β-chitin: hydrolysis by chitinases A and B from Serratia marcescens 2170. Biochem. J. 388 (2005) 851–856. [PMID: 15717865]
3.  Ohnuma, T., Numata, T., Osawa, T., Mizuhara, M., Lampela, O., Juffer, A.H., Skriver, K. and Fukamizo, T. A class V chitinase from Arabidopsis thaliana: gene responses, enzymatic properties, and crystallographic analysis. Planta 234 (2011) 123–137. [PMID: 21390509]
4.  Gutierrez-Roman, M.I., Dunn, M.F., Tinoco-Valencia, R., Holguin-Melendez, F., Huerta-Palacios, G. and Guillen-Navarro, K. Potentiation of the synergistic activities of chitinases ChiA, ChiB and ChiC from Serratia marcescens CFFSUR-B2 by chitobiase (Chb) and chitin binding protein (CBP). World J Microbiol Biotechnol 30 (2014) 33–42. [PMID: 23824666]
[EC 3.2.1.200 created 2017]
 
 
EC 3.2.1.201     
Accepted name: exo-chitinase (reducing end)
Reaction: Hydrolysis of N,N′-diacetylchitobiose from the reducing end of chitin and chitodextrins.
Other name(s): chiA (gene name)
Systematic name: (1→4)-2-acetamido-2-deoxy-β-D-glucan diacetylchitobiohydrolase (reducing end)
Comments: The enzyme hydrolyses the second glycosidic (1→4) linkage from reducing ends of chitin and chitodextrin molecules, liberating N,N′-diacetylchitobiose disaccharides. cf. EC 3.2.1.200, exo-chitinase (non-reducing end).
References:
1.  Hult, E.L., Katouno, F., Uchiyama, T., Watanabe, T. and Sugiyama, J. Molecular directionality in crystalline β-chitin: hydrolysis by chitinases A and B from Serratia marcescens 2170. Biochem. J. 388 (2005) 851–856. [PMID: 15717865]
2.  Nakagawa, Y.S., Eijsink, V.G., Totani, K. and Vaaje-Kolstad, G. Conversion of α-chitin substrates with varying particle size and crystallinity reveals substrate preferences of the chitinases and lytic polysaccharide monooxygenase of Serratia marcescens. J. Agric. Food Chem. 61 (2013) 11061–11066. [PMID: 24168426]
3.  Gutierrez-Roman, M.I., Dunn, M.F., Tinoco-Valencia, R., Holguin-Melendez, F., Huerta-Palacios, G. and Guillen-Navarro, K. Potentiation of the synergistic activities of chitinases ChiA, ChiB and ChiC from Serratia marcescens CFFSUR-B2 by chitobiase (Chb) and chitin binding protein (CBP). World J Microbiol Biotechnol 30 (2014) 33–42. [PMID: 23824666]
4.  Brurberg, M.B., Nes, I.F. and Eijsink, V.G. Comparative studies of chitinases A and B from Serratia marcescens. Microbiology 142 (1996) 1581–1589. [PMID: 8757722]
[EC 3.2.1.201 created 2017]
 
 
EC 3.2.1.202     
Accepted name: endo-chitodextinase
Reaction: Hydrolysis of chitodextrins, releasing N,N′-diacetylchitobiose and small amounts of N,N′,N′′-triacetylchitotriose.
Other name(s): endo I (gene name); chitodextrinase (ambiguous); endolytic chitodextrinase; periplasmic chitodextrinase
Systematic name: (1→4)-2-acetamido-2-deoxy-β-D-glucan diacetylchitobiohydrolase (endo-cleaving)
Comments: The enzyme, characterized from the bacterium Vibrio furnissii, is an endo-cleaving chitodextrinase that participates in the the chitin catabolic pathway found in members of the Vibrionaceae. Unlike EC 3.2.1.14, chitinase, it has no activity on chitin. The smallest substrate is a tetrasaccharide, and the final products are N,N′-diacetylchitobiose and small amounts of N,N′,N′′-triacetylchitotriose. cf. EC 3.2.1.200, exo-chitinase (non-reducing end), and EC 3.2.1.201, exo-chitinase (reducing end).
References:
1.  Bassler, B.L., Yu, C., Lee, Y.C. and Roseman, S. Chitin utilization by marine bacteria. Degradation and catabolism of chitin oligosaccharides by Vibrio furnissii. J. Biol. Chem. 266 (1991) 24276–24286. [PMID: 1761533]
2.  Keyhani, N.O. and Roseman, S. The chitin catabolic cascade in the marine bacterium Vibrio furnissii. Molecular cloning, isolation, and characterization of a periplasmic chitodextrinase. J. Biol. Chem. 271 (1996) 33414–33424. [PMID: 8969204]
[EC 3.2.1.202 created 2017]
 
 
EC 3.2.1.203     
Accepted name: carboxymethylcellulase
Reaction: Endohydrolysis of (1→4)-β-D-glucosidic linkages in (carboxymethyl)cellulose.
Other name(s): CMCase
Systematic name: 4-β-D-(carboxymethyl)glucan 4-(carboxymethyl)glucanohydrolase
Comments: The enzyme from the acidophilic bacterium Alicyclobacillus acidocaldarius is an endo-cleaving hydrolase that cleaves β(1→4)-linked residues. However, it is specific for (carboxymethyl)cellulose and does not act on cellulosic substrates such as avicel.
References:
1.  Morana, A., Esposito, A., Maurelli, L., Ruggiero, G., Ionata, E., Rossi, M. and La Cara, F. A novel thermoacidophilic cellulase from Alicyclobacillus acidocaldarius. Protein Pept. Lett. 15 (2008) 1017–1021. [PMID: 18991780]
[EC 3.2.1.203 created 2017]
 
 
EC 3.2.1.204     
Accepted name: 1,3-α-isomaltosidase
Reaction: cyclobis-(1→6)-α-nigerosyl + 2 H2O = 2 isomaltose (overall reaction)
(1a) cyclobis-(1→6)-α-nigerosyl + H2O = α-isomaltosyl-(1→3)-isomaltose
(1b) α-isomaltosyl-(1→3)-isomaltose + H2O = 2 isomaltose
Systematic name: 1,3-α-isomaltohydrolase (configuration-retaining)
Comments: The enzyme, characterized from the bacteria Bacillus sp. NRRL B-21195 and Kribbella flavida, participates in the degradation of starch. The cyclic tetrasaccharide cyclobis-(1→6)-α-nigerosyl is formed from starch extracellularly and imported into the cell, where it is degraded to glucose.
References:
1.  Kim, Y.K., Kitaoka, M., Hayashi, K., Kim, C.H. and Cote, G.L. Purification and characterization of an intracellular cycloalternan-degrading enzyme from Bacillus sp. NRRL B-21195. Carbohydr. Res. 339 (2004) 1179–1184. [PMID: 15063208]
2.  Tagami, T., Miyano, E., Sadahiro, J., Okuyama, M., Iwasaki, T. and Kimura, A. Two novel glycoside hydrolases responsible for the catabolism of cyclobis-(1→6)-α-nigerosyl. J. Biol. Chem. 291 (2016) 16438–16447. [PMID: 27302067]
[EC 3.2.1.204 created 2017]
 
 
EC 3.2.1.205     
Accepted name: isomaltose glucohydrolase
Reaction: isomaltose + H2O = β-D-glucose + D-glucose
Systematic name: isomaltose 6-α-glucohydrolase (configuration-inverting)
Comments: The enzyme catalyses the hydrolysis of α-1,6-glucosidic linkages from the non-reducing end of its substrate. Unlike EC 3.2.1.10, oligo-1,6-glucosidase, the enzyme inverts the anomeric configuration of the released residue. The enzyme can also act on panose and maltotriose at a lower rate.
References:
1.  Tagami, T., Miyano, E., Sadahiro, J., Okuyama, M., Iwasaki, T. and Kimura, A. Two novel glycoside hydrolases responsible for the catabolism of cyclobis-(1→6)-α-nigerosyl. J. Biol. Chem. 291 (2016) 16438–16447. [PMID: 27302067]
[EC 3.2.1.205 created 2017]
 
 
EC 3.2.1.206     
Accepted name: oleuropein β-glucosidase
Reaction: oleuropein + H2O = oleuropein aglycone + D-glucopyranose
Glossary: oleuropein aglycone = methyl (2S,3E,4S)-4-{2-[2-(3,4-dihydroxyphenyl)ethoxy]-2-oxoethyl}-3-ethylidene-2-hydroxy-3,4-dihydro-2H-pyran-5-carboxylate
oleuropein = methyl (2R,3E,4S)-4-{2-[2-(3,4-dihydroxyphenyl)ethoxy]-2-oxoethyl}-3-ethylidene-2-(β-D-glucopyranosyloxy)-3,4-dihydro-2H-pyran-5-carboxylate
ligstroside = methyl (2S,3E,4S)-3-ethylidene-2-(β-D-glucopyranosyloxy)-4-{2-[2-(4-hydroxyphenyl)ethoxy]-2-oxoethyl}-3,4-dihydro-2H-pyran-5-carboxylate
Other name(s): OeGLU (gene name)
Systematic name: oleuropein 2-β-D-glucohydrolase
Comments: Oleuropein is a glycosylated secoiridoid exclusively biosynthesized by members of the Oleaceae plant family where it is part of a defence system againt herbivores. The enzyme also hydrolyses ligstroside and demethyloleuropein.
References:
1.  Ciafardini, G., Marsilio, V., Lanza, B. and Pozzi, N. Hydrolysis of oleuropein by Lactobacillus plantarum strains associated with olive fermentation. Appl. Environ. Microbiol. 60 (1994) 4142–4147. [PMID: 16349442]
2.  Romero-Segura, C., Sanz, C. and Perez, A.G. Purification and characterization of an olive fruit β-glucosidase involved in the biosynthesis of virgin olive oil phenolics. J. Agric. Food Chem. 57 (2009) 7983–7988. [PMID: 19689134]
3.  Gutierrez-Rosales, F., Romero, M.P., Casanovas, M., Motilva, M.J. and Minguez-Mosquera, M.I. β-Glucosidase involvement in the formation and transformation of oleuropein during the growth and development of olive fruits (Olea europaea L. cv. Arbequina) grown under different farming practices. J. Agric. Food Chem. 60 (2012) 4348–4358. [PMID: 22475562]
4.  Koudounas, K., Banilas, G., Michaelidis, C., Demoliou, C., Rigas, S. and Hatzopoulos, P. A defence-related Olea europaea β-glucosidase hydrolyses and activates oleuropein into a potent protein cross-linking agent. J. Exp. Bot. 66 (2015) 2093–2106. [PMID: 25697790]
5.  Koudounas, K., Thomopoulou, M., Michaelidis, C., Zevgiti, E., Papakostas, G., Tserou, P., Daras, G. and Hatzopoulos, P. The C-domain of oleuropein β-glucosidase assists in protein folding and sequesters the enzyme in nucleus. Plant Physiol. 174 (2017) 1371–1383. [PMID: 28483880]
[EC 3.2.1.206 created 2017]
 
 
EC 3.2.1.207     
Accepted name: mannosyl-oligosaccharide α-1,3-glucosidase
Reaction: (1) Glc2Man9GlcNAc2-[protein] + H2O = GlcMan9GlcNAc2-[protein] + β-D-glucopyranose
(2) GlcMan9GlcNAc2-[protein] + H2O = Man9GlcNAc2-[protein] + β-D-glucopyranose
Glossary: Glc2Man9GlcNAc2-[protein] = {α-D-Glc-(1→3)-α-D-Glc-(1→3)-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→2)-α-D-Man-(1→6)]-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc}-N-Asn-[protein]
GlcMan9GlcNAc2-[protein] = {α-D-Glc-(1→3)-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→2)-α-D-Man-(1→6)]-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc}-N-Asn-[protein]
Man9GlcNAc2-[protein] = {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→2)-α-D-Man-(1→6)]-α-D-Man-(1→6)]-β-D-Man-(1→4)-β-D-GlcNAc-(1→4)-β-D-GlcNAc}-N-Asn-[protein]
Other name(s): ER glucosidase II; α-glucosidase II; trimming glucosidase II; ROT2 (gene name); GTB1 (gene name); GANAB (gene name); PRKCSH (gene name)
Systematic name: Glc2Man9GlcNAc2-[protein] 3-α-glucohydrolase (configuration-inverting)
Comments: This eukaryotic enzyme cleaves off sequentially the two α-1,3-linked glucose residues from the Glc2Man9GlcNAc2 oligosaccharide precursor of immature N-glycosylated proteins.
References:
1.  Trombetta, E.S., Simons, J.F. and Helenius, A. Endoplasmic reticulum glucosidase II is composed of a catalytic subunit, conserved from yeast to mammals, and a tightly bound noncatalytic HDEL-containing subunit. J. Biol. Chem. 271 (1996) 27509–27516. [PMID: 8910335]
2.  Ziak, M., Meier, M., Etter, K.S. and Roth, J. Two isoforms of trimming glucosidase II exist in mammalian tissues and cell lines but not in yeast and insect cells. Biochem. Biophys. Res. Commun. 280 (2001) 363–367. [PMID: 11162524]
3.  Wilkinson, B.M., Purswani, J. and Stirling, C.J. Yeast GTB1 encodes a subunit of glucosidase II required for glycoprotein processing in the endoplasmic reticulum. J. Biol. Chem. 281 (2006) 6325–6333. [PMID: 16373354]
4.  Mora-Montes, H.M., Bates, S., Netea, M.G., Diaz-Jimenez, D.F., Lopez-Romero, E., Zinker, S., Ponce-Noyola, P., Kullberg, B.J., Brown, A.J., Odds, F.C., Flores-Carreon, A. and Gow, N.A. Endoplasmic reticulum α-glycosidases of Candida albicans are required for N glycosylation, cell wall integrity, and normal host-fungus interaction. Eukaryot Cell 6 (2007) 2184–2193. [PMID: 17933909]
[EC 3.2.1.207 created 2018]
 
 
EC 3.2.1.208     
Accepted name: glucosylglycerate hydrolase
Reaction: 2-O-(α-D-glucopyranosyl)-D-glycerate + H2O = D-glucopyranose + D-glycerate
Other name(s): GG hydrolase; GgH
Systematic name: 2-O-(α-D-glucopyranosyl)-D-glycerate D-glucohydrolase
Comments: The enzyme has been isolated from nontuberculous mycobacteria (e.g. Mycobacterium hassiacum), which accumulate 2-O-(α-D-glucopyranosyl)-D-glycerate during growth under nitrogen deprivation.
References:
1.  Alarico, S., Costa, M., Sousa, M.S., Maranha, A., Lourenco, E.C., Faria, T.Q., Ventura, M.R. and Empadinhas, N. Mycobacterium hassiacum recovers from nitrogen starvation with up-regulation of a novel glucosylglycerate hydrolase and depletion of the accumulated glucosylglycerate. Sci. Rep. 4:6766 (2014). [PMID: 25341489]
2.  Cereija, T.B., Alarico, S., Empadinhas, N. and Pereira, P.JB. Production, crystallization and structure determination of a mycobacterial glucosylglycerate hydrolase. Acta Crystallogr. F Struct. Biol. Commun. 73 (2017) 536–540. [PMID: 28876234]
[EC 3.2.1.208 created 2018]
 
 
EC 3.2.1.209     
Accepted name: endoplasmic reticulum Man9GlcNAc2 1,2-α-mannosidase
Reaction: Man9GlcNAc2-[protein] + H2O = Man8GlcNAc2-[protein] (isomer 8A1,2,3B1,3) + D-mannopyranose
Glossary: Man9GlcNAc2-[protein] = {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→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]
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]
Other name(s): MAN1B1 (gene name); MNS1 (gene name); MNS3 (gene name)
Systematic name: Man9GlcNAc2-[protein]2-α-mannohydrolase (configuration-inverting)
Comments: The enzyme, located in the endoplasmic reticulum, primarily trims a single α-1,2-linked mannose residue from Man9GlcNAc2 to produce Man8GlcNAc2 isomer 8A1,2,3B1,3 (the names of the isomers listed here are based on a nomenclature system proposed by Prien et al [7]). The removal of the single mannosyl residue occurs in all eukaryotes as part of the processing of N-glycosylated proteins, and is absolutely essential for further elongation of the outer chain of properly-folded N-glycosylated proteins in yeast. In addition, the enzyme is involved in glycoprotein quality control at the ER quality control compartment (ERQC), helping to target misfolded glycoproteins for degradation. When present at very high concentrations in the ERQC, the enzyme can trim the carbohydrate chain further to Man(5-6)GlcNAc2.
References:
1.  Jelinek-Kelly, S. and Herscovics, A. Glycoprotein biosynthesis in Saccharomyces cerevisiae. Purification of the α-mannosidase which removes one specific mannose residue from Man9GlcNAc. J. Biol. Chem. 263 (1988) 14757–14763. [PMID: 3049586]
2.  Ziegler, F.D. and Trimble, R.B. Glycoprotein biosynthesis in yeast: purification and characterization of the endoplasmic reticulum Man9 processing α-mannosidase. Glycobiology 1 (1991) 605–614. [PMID: 1822240]
3.  Gonzalez, D.S., Karaveg, K., Vandersall-Nairn, A.S., Lal, A. and Moremen, K.W. Identification, expression, and characterization of a cDNA encoding human endoplasmic reticulum mannosidase I, the enzyme that catalyzes the first mannose trimming step in mammalian Asn-linked oligosaccharide biosynthesis. J. Biol. Chem. 274 (1999) 21375–21386. [PMID: 10409699]
4.  Herscovics, A., Romero, P.A. and Tremblay, L.O. The specificity of the yeast and human class I ER α 1,2-mannosidases involved in ER quality control is not as strict previously reported. Glycobiology 12 (2002) 14G–15G. [PMID: 12090241]
5.  Avezov, E., Frenkel, Z., Ehrlich, M., Herscovics, A. and Lederkremer, G.Z. Endoplasmic reticulum (ER) mannosidase I is compartmentalized and required for N-glycan trimming to Man5-6GlcNAc2 in glycoprotein ER-associated degradation. Mol. Biol. Cell 19 (2008) 216–225. [PMID: 18003979]
6.  Liebminger, E., Huttner, S., Vavra, U., Fischl, R., Schoberer, J., Grass, J., Blaukopf, C., Seifert, G.J., Altmann, F., Mach, L. and Strasser, R. Class I α-mannosidases are required for N-glycan processing and root development in Arabidopsis thaliana. Plant Cell 21 (2009) 3850–3867. [PMID: 20023195]
7.  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. [PMID: 19181540]
[EC 3.2.1.209 created 2019]
 
 
EC 3.2.1.210     
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].
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. [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 3.2.1.211     
Accepted name: endo-(1→3)-fucoidanase
Reaction: endohydrolysis of (1→3)-α-L-fucoside linkages in fucan
Other name(s): α-L-fucosidase (incorrect); poly(1,3-α-L-fucoside-2/4-sulfate) glycanohydrolase
Systematic name: poly[(1→3)-α-L-fucoside-2/4-sulfate] glycanohydrolase
Comments: The enzyme specifically hydrolyses (1→3)-α-L-fucoside linkages in fucan. Fucans are found mainly in different species of seaweed and are sulfated polysaccharides with a backbone of (1→3)-linked or alternating (1→3)- and (1→4)-linked α-L-fucopyranosyl residues. In the literature, the sulfated polysaccharides are often called fucoidans. Fucoidans include polysaccharides with a relatively low proportion of fucose and some polysaccharides that have a backbone composed of other saccharides with fucose in the branching side chains. The sulfation of the α-L-fucopyranosyl residues may occur at positions 2 and 4. The enzyme degrades fucan to sulfated α-L-fucooligosaccharides but neither L-fucose nor small fucooligosaccharides are produced.
References:
1.  Thanassi, N.M. and Nakada, H.I. Enzymic degradation of fucoidan by enzymes from the hepatopancreas of abalone, Halotus species. Arch. Biochem. Biophys. 118 (1967) 172–177.
2.  Bakunina, I.Iu, Nedashkovskaia, O.I., Alekseeva, S.A., Ivanova, E.P., Romanenko, L.A., Gorshkova, N.M., Isakov, V.V., Zviagintseva, T.N. and Mikhailov, V.V. [Degradation of fucoidan by the marine proteobacterium Pseudoalteromonas citrea] Mikrobiologiia 71 (2002) 49–55. [PMID: 11910806] (in Russian)
3.  Berteau, O. and Mulloy, B. Sulfated fucans, fresh perspectives: structures, functions, and biological properties of sulfated fucans and an overview of enzymes active toward this class of polysaccharide. Glycobiology 13 (2003) 29R–40R. [PMID: 12626402]
4.  Bilan, M.I., Kusaykin, M.I., Grachev, A.A., Tsvetkova, E.A., Zvyagintseva, T.N., Nifantiev, N.E. and Usov, A.I. Effect of enzyme preparation from the marine mollusk Littorina kurila on fucoidan from the brown alga Fucus distichus. Biochemistry (Mosc.) 70 (2005) 1321–1326. [PMID: 16417453]
[EC 3.2.1.211 created 1972 as EC 3.2.1.44, part transferred 2020 to EC 3.2.1.211 ]
 
 
EC 3.2.1.212     
Accepted name: endo-(1→4)-fucoidanase
Reaction: endohydrolysis of (1→4)-α-L-fucoside linkages in fucan
Other name(s): α-L-fucosidase (incorrect); poly(1,4-α-L-fucoside-2/3-sulfate) glycanohydrolase
Systematic name: poly[(1→4)-α-L-fucoside-2/3-sulfate] glycanohydrolase
Comments: The enzyme specifically hydrolyses (1→4)-α-L-fucoside linkages in fucan. Fucans are found mainly in different species of seaweed and are sulfated polysaccharides with a backbone of (1→3)-linked or alternating (1→3)- and (1→4)-linked α-L-fucopyranosyl residues. In the literature, the sulfated polysaccharides are often called fucoidans. Fucoidans include polysaccharides with a relatively low proportion of fucose and some polysaccharides that have a backbone composed of other saccharides with fucose in the branching side chains. The sulfation of the α-L-fucopyranosyl residues may occur at positions 2 and 3. The enzyme degrades fucan to sulfated α-L-fucooligosaccharides but neither L-fucose nor small fucooligosaccharides are produced.
References:
1.  Thanassi, N.M. and Nakada, H.I. Enzymic degradation of fucoidan by enzymes from the hepatopancreas of abalone, Halotus species. Arch. Biochem. Biophys. 118 (1967) 172–177.
2.  Berteau, O. and Mulloy, B. Sulfated fucans, fresh perspectives: structures, functions, and biological properties of sulfated fucans and an overview of enzymes active toward this class of polysaccharide. Glycobiology 13 (2003) 29R–40R. [PMID: 12626402]
3.  Descamps, V., Colin, S., Lahaye, M., Jam, M., Richard, C., Potin, P., Barbeyron, T., Yvin, J.C. and Kloareg, B. Isolation and culture of a marine bacterium degrading the sulfated fucans from marine brown algae. Mar Biotechnol (NY) 8 (2006) 27–39. [PMID: 16222488]
4.  Kim, W.J., Kim, S.M., Lee, Y.H., Kim, H.G., Kim, H.K., Moon, S.H., Suh, H.H., Jang, K.H. and Park, Y.I. Isolation and characterization of marine bacterial strain degrading fucoidan from Korean Undaria pinnatifida Sporophylls. J. Microbiol. Biotechnol. 18 (2008) 616–623. [PMID: 18467852]
5.  Silchenko, A.S., Kusaykin, M.I., Kurilenko, V.V., Zakharenko, A.M., Isakov, V.V., Zaporozhets, T.S., Gazha, A.K. and Zvyagintseva, T.N. Hydrolysis of fucoidan by fucoidanase isolated from the marine bacterium, Formosa algae. Mar. Drugs 11 (2013) 2413–2430. [PMID: 23852092]
6.  Silchenko, A.S., Kusaykin, M.I., Zakharenko, A.M., Menshova, R.V., Khanh, H.H.N., Dmitrenok, P.S., Isakov, V.V., Zvyagintseva, T.N. Endo-1,4-fucoidanase from vietnamese marine mollusk Lambis sp. which producing sulphated fucooligosaccharides. J. Mol. Catal. B 102 (2014) 154–160.
7.  Silchenko, A.S., Ustyuzhanina, N.E., Kusaykin, M.I., Krylov, V.B., Shashkov, A.S., Dmitrenok, A.S., Usoltseva, R.V., Zueva, A.O., Nifantiev, N.E. and Zvyagintseva, T.N. Expression and biochemical characterization and substrate specificity of the fucoidanase from Formosa algae. Glycobiology 27 (2017) 254–263. [PMID: 28031251]
[EC 3.2.1.212 created 1972 as EC 3.2.1.44, part transferred 2020 to EC 3.2.1.212]
 
 
EC 3.2.1.213     
Accepted name: galactan exo-1,6-β-galactobiohydrolase (non-reducing end)
Reaction: Hydrolysis of (1→6)-β-D-galactosidic linkages in arabinogalactan proteins and (1→3):(1→6)-β-galactans to yield (1→6)-β-galactobiose as the final product.
Other name(s): exo-β-1,6-galactobiohydrolase; 1,6Gal (gene name)
Systematic name: exo-β-(1→6)-galactobiohydrolase (non-reducing end)
Comments: The enzyme, characterized from the bacterium Bifidobacterium longum, specifically hydrolyses (1→6)-β-galactobiose from the non-reducing terminal of (1→6)-β-D-galactooligosaccharides with a degree of polymerization (DP) of 3 or higher, using an exo mode of action. The enzyme cannot hydrolyse α-L-arabinofuranosylated (1→6)-β-galactans (as found in arabinogalactans) and does not act on (1→3)-β-D- or (1→4)-β-D-galactans. cf. EC 3.2.1.164, galactan endo-1,6-β-galactosidase.
References:
1.  Fujita, K., Sakamoto, A., Kaneko, S., Kotake, T., Tsumuraya, Y. and Kitahara, K. Degradative enzymes for type II arabinogalactan side chains in Bifidobacterium longum subsp. longum. Appl. Microbiol. Biotechnol. 103 (2019) 1299–1310. [PMID: 30564851]
[EC 3.2.1.213 created 2020]
 
 
EC 3.2.1.214     
Accepted name: exo β-1,2-glucooligosaccharide sophorohydrolase (non-reducing end)
Reaction: [(1→2)-β-D-glucosyl]n + H2O = sophorose + [(1→2)-β-D-glucosyl]n-2
Glossary: sophorose = β-D-glucopyranosyl-(1→2)-D-glucopyranose
Systematic name: exo (1→2)-β-D-glucooligosaccharide sophorohydrolase (non-reducing end)
Comments: The enzyme, characterized from the bacterium Parabacteroides distasonis, specifically hydrolyses (1→2)-β-D-glucooligosaccharides to sophorose. The best substrates are the tetra- and pentasaccharides. The enzyme is not able to cleave the trisaccharide, and activity with longer linear (1→2)-β-D-glucans is quite low. This enzyme acts in exo mode and is not able to hydrolyse cyclic (1→2)-β-D-glucans.
References:
1.  Shimizu, H., Nakajima, M., Miyanaga, A., Takahashi, Y., Tanaka, N., Kobayashi, K., Sugimoto, N., Nakai, H. and Taguchi, H. Characterization and structural analysis of a novel exo-type enzyme acting on β-1,2-glucooligosaccharides from Parabacteroides distasonis. Biochemistry 57 (2018) 3849–3860. [PMID: 29763309]
[EC 3.2.1.214 created 2020]