7C6C

Crystal structure of native chitosanase from Bacillus subtilis MY002

Summary for 7C6C

• Entry DOI: 10.2210/pdb7c6c/pdb
• Descriptor: Chitosanase, (2S)-2-hydroxybutanedioic acid (3 entities in total)
• Functional Keywords: chitosanase, hydrolase
• Biological source: Bacillus subtilis subsp. subtilis str. 168
• Total number of polymer chains: 1
• Total formula weight: 27597.67

Authors

Gou, Y.,Liu, Z.C.,Xie, T.,Wang, G.G. (deposition date: 2020-05-21, release date: 2021-03-31, Last modification date: 2023-11-29)

Primary citation

Li, Y.,Gou, Y.,Liu, Z.,Xie, T.,Wang, G.
Structure-based rational design of chitosanase CsnMY002 for high yields of chitobiose.
Colloids Surf B Biointerfaces, 202:111692-111692, 2021

PubMed Abstract: Chitosan oligosaccharides (COS) are attractive active molecules for biomedical applications. Currently, the prohibitively high cost of producing fully defined COS hampers extensive studies on their biological activity and restricts their use in various industries. Thus, cost-effective production of pure COS is of major importance. In this report, chitosanase from Bacillus subtilis MY002 (CsnMY002) was prepared for COS production. The structure of apo CsnMY002 displayed an unexpected tunnel-like substrate-binding site and the structure of the CsnMY002_E19A/(GlcN) complex highlighted the "4 + 2″ splitting of hexaglucosamine even though the "3 + 3″ splitting is also observed in the TLC analysis of the enzyme products for hexaglucosamine. Structure based rational design was performed to generate mutants for chitobiose production. The CsnMY002_G21 K mutant produced chitobiose with a relative content > 87 % from chitosan with a low degree of acetylation, and 50.65 mg chitobiose with a purity > 98 % was prepared from 100 mg chitosan. The results provide insight on the catalytic mechanism of chitosanase and underpin future biomedical applications of pure chitobiose.

PubMed: 33744813
DOI: 10.1016/j.colsurfb.2021.111692

Experimental method

X-RAY DIFFRACTION (1.258 Å)