IUBMB Enzyme Nomenclature


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.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 59793-96-3


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 created 1978 (EC created 1984, incorporated 2008), modified 2008, modified 2011]

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