ExplorEnz: EC 3.2.1.18*

Your query returned 11 entries. Printable version

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.

Links to other databases:

BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 9001-67-6

References:

1.	Schauer, R. Sialic acids. Adv. Carbohydr. Chem. Biochem. 40 (1982) 131–234. [DOI] [PMID: 6762816]
2.	Cabezas, J.A. Some questions and suggestions on the type references of the official nomenclature (IUB) for sialidase(s) and endosialidase. Biochem. J. 278 (1991) 311–312. [PMID: 1883340]

[EC 3.2.1.18 created 1961, modified 1999]

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.

Links to other databases:

BRENDA, EXPASY, KEGG, MetaCyc, PDB

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. [DOI] [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. [DOI] [PMID: 21147778]

[EC 3.2.1.180 created 2011]

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.

Links to other databases:

BRENDA, EXPASY, KEGG, MetaCyc

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. [DOI] [PMID: 21653698]

[EC 3.2.1.181 created 2012]

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.

Links to other databases:

BRENDA, EXPASY, KEGG, MetaCyc, PDB

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. [DOI] [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. [DOI] [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. [DOI] [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. [DOI] [PMID: 21421370]

[EC 3.2.1.182 created 2012]

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

For diagram of N-acetylneuraminic acid biosynthesis, click here, and for mechanism, click here

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).

Links to other databases:

BRENDA, EXPASY, KEGG, MetaCyc, PDB

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. [DOI] [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. [DOI] [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. [DOI] [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. [DOI] [PMID: 15518580]

[EC 3.2.1.183 created 2012]

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

For diagram of legionaminic acid biosynthesis, click here, and for mechanism, click here

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].

Links to other databases:

BRENDA, EXPASY, KEGG, MetaCyc, PDB

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. [DOI] [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. [DOI] [PMID: 19282391]

[EC 3.2.1.184 created 2012]

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

Links to other databases:

BRENDA, EXPASY, KEGG, MetaCyc, PDB

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. [DOI] [PMID: 24385433]

[EC 3.2.1.185 created 2013]

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.

Links to other databases:

BRENDA, EXPASY, KEGG, MetaCyc

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. [DOI] [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. [DOI] [PMID: 16289258]

[EC 3.2.1.186 created 2013]

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.

Links to other databases:

BRENDA, EXPASY, KEGG, MetaCyc, PDB

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. [DOI] [PMID: 21149454]

[EC 3.2.1.187 created 2013]

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.

Links to other databases:

BRENDA, EXPASY, KEGG, MetaCyc

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. [DOI] [PMID: 8013661]

[EC 3.2.1.188 created 2013]

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

For diagram of diosgenin catabolism, click here

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).

Links to other databases:

BRENDA, EXPASY, KEGG, MetaCyc

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]