6JEA

crystal structure of a beta-N-acetylhexosaminidase

Summary for 6JEA

• Entry DOI: 10.2210/pdb6jea/pdb
• Descriptor: Beta-N-acetylhexosaminidase, 2-acetamido-2-deoxy-beta-D-glucopyranose, ZINC ION, ... (4 entities in total)
• Functional Keywords: hydrolase, catalyze, acetamidodeoxyhexohydrolase
• Biological source: Akkermansia muciniphila (strain ATCC BAA-835 / Muc)
• Total number of polymer chains: 1
• Total formula weight: 53914.66

Authors

Chen, X.,Wang, J.C.,Liu, M.J.,Yang, W.Y.,Wang, Y.Z.,Tang, R.P.,Zhang, M. (deposition date: 2019-02-04, release date: 2019-03-13, Last modification date: 2023-11-22)

Primary citation

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., 511:833-839, 2019

PubMed Abstract: β-N-acetylhexosaminidases from Akkermansia muciniphila was reported to perform the crystal structure with GlcNAc complex, which proved to be the substrate of Am2301. Domain II of Am2301 is consisted of amino acid residues 111-489 and is folded as a (β/α) barrel with the active site combined of the glycosyl hydrolases. Crystallographic evidence showed that Asp-278 and Glu-279 could be the catalytic site and Tyr-373 may plays a role on binding the substrate. Moreover, Am2301 prefers to bind Zn ion, which similar to other GH 20 family. Enzyme activity and kinetic parameters of wild-type Am2301 and mutants proved that Asp-278 and Glu-279 are the catalytic sites and they play a critical role on the catalytic process. Overall, our results demonstrate that Am2301 and its complex with GlcNAC provide obvious structural evidence for substrate-assisted catalysis. Obviously, this expands our understanding on the mode of substrate-assisted reaction for this enzyme family in Akkermansia muciniphila.

PubMed: 30846208
DOI: 10.1016/j.bbrc.2019.02.074

Experimental method

X-RAY DIFFRACTION (2.275 Å)