6jea

Structural highlights

Function

H2018_AKKM8 Hydrolyzes terminal GlcNAc residues from terminally unbranched N-glycans and from chitobiose. Hydrolyzes beta-1,6-linked N-acetylglucosamine and beta-1,4-linked N-acetylgalactosamine from pNP-alpha-GalNAc[beta1,3Gal]beta1,6GlcNAc and pNP-beta-GlcNAc-beta1,4-GalNAc substrates, respectively, as well as beta-1,2-linked N-acetylglucosamine units from the non-reducing end of N-glycans. Hydrolyzes GlcNAc residues linked to alpha1,3- or alpha1,6-mannose branch, but has low activity on substrates with more than one GlcNAc residue on one of the mannose branches. Releases terminal GlcNAc moieties from the N-glycopeptide Gly-Glu-Asn-(GlcNAc2Man3GlcNAc2)-Arg with high efficiency. Has moderate hydrolytic activity on the chitobiose moiety of N-glycopeptide substrate Gly-Glu-Asn-(GlcNAc2)-Arg. Does not hydrolyze GlcNAc residues from N-glycan structures bearing a bisecting GlcNAc moiety (beta1,4-linked GlcNAc to the beta1,4-linked core mannose) (PubMed:29304441). Potentially capable of cleaving the specific glycoside linkages in the process of mucin degradation in human intestinal tract (Probable). Hydrolyzes synthetic substrate pNP-beta-GlcNAc with high activity and pNP-beta-GalNAc to a lesser extent (PubMed:29304441, PubMed:30846208). Does not hydrolyze pNP-beta-glucose, pNP-beta-galactose, pNP-alpha-glucose, pNP-alpha-galactose, pNP-alpha-GlcNAc or pNP-alpha-fucose (PubMed:29304441).^{[1] [2]}

See Also

• Beta-N-acetylhexosaminidase 3D structures

References

1. ↑ Wang M, Zhang XY, Guo RR, Cai ZP, Hu XC, Chen H, Wei S, Voglmeir J, Liu L. Cloning, purification and biochemical characterization of two β-N-acetylhexosaminidases from the mucin-degrading gut bacterium Akkermansia muciniphila. Carbohydr Res. 2018 Mar 2;457:1-7. PMID:29304441 doi:10.1016/j.carres.2017.12.007
2. ↑ Chen X, Wang J, Liu M, Yang W, Wang Y, Tang R, Zhang M. Crystallographic evidence for substrate-assisted catalysis of beta-N-acetylhexosaminidas from Akkermansia muciniphila. Biochem Biophys Res Commun. 2019 Apr 16;511(4):833-839. doi:, 10.1016/j.bbrc.2019.02.074. Epub 2019 Mar 4. PMID:30846208 doi:http://dx.doi.org/10.1016/j.bbrc.2019.02.074
3. ↑ Chen X, Wang J, Liu M, Yang W, Wang Y, Tang R, Zhang M. Crystallographic evidence for substrate-assisted catalysis of beta-N-acetylhexosaminidas from Akkermansia muciniphila. Biochem Biophys Res Commun. 2019 Apr 16;511(4):833-839. doi:, 10.1016/j.bbrc.2019.02.074. Epub 2019 Mar 4. PMID:30846208 doi:http://dx.doi.org/10.1016/j.bbrc.2019.02.074