Crystal structure of the GH-46 subclass III chitosanase from Bacillus circulans MH-K1 in complex with chitotetraose.
Bacillus circulans
Chitosanase
Cleavage specificity
GH-46
Glycoside hydrolase
Journal
Biochimica et biophysica acta. General subjects
ISSN: 1872-8006
Titre abrégé: Biochim Biophys Acta Gen Subj
Pays: Netherlands
ID NLM: 101731726
Informations de publication
Date de publication:
27 Dec 2023
27 Dec 2023
Historique:
received:
22
06
2023
revised:
12
12
2023
accepted:
21
12
2023
medline:
2
1
2024
pubmed:
2
1
2024
entrez:
29
12
2023
Statut:
aheadofprint
Résumé
Chitosanases (EC 3.2.1.132) hydrolyze chitosan which is a polymer of glucosamine (GlcN) linked by β - 1,4 bonds, and show cleavage specificity against partially acetylated chitosan containing N-acetylglucosamine (GlcNAc) residues. Chitosanases' structural underpinnings for cleavage specificity and the conformational switch from open to closed structures are still a mystery. The GH-46 subclass III chitosanase from Bacillus circulans MH-K1 (MH-K1 chitosanase), which also catalyzes the hydrolysis of GlcN-GlcNAc bonds in addition to GlcN-GlcN, has had its chitotetraose [(GlcN) The MH-K1 chitosanase's (GlcN) Although GH-46 chitosanases vary in the finer details of the subsites defining cleavage specificity, they share similar structural characteristics in substrate-binding, catalytic processes, and potentially in conformational change. The precise binding of a GlcN residue to the -2 subsite is essential for the conformational shift that occurs in all GH-46 chitosanases, as shown by the crystal structures of the apo- and substrate-bound forms of MH-K1 chitosanase.
Sections du résumé
BACKGROUND
BACKGROUND
Chitosanases (EC 3.2.1.132) hydrolyze chitosan which is a polymer of glucosamine (GlcN) linked by β - 1,4 bonds, and show cleavage specificity against partially acetylated chitosan containing N-acetylglucosamine (GlcNAc) residues. Chitosanases' structural underpinnings for cleavage specificity and the conformational switch from open to closed structures are still a mystery.
METHODS
METHODS
The GH-46 subclass III chitosanase from Bacillus circulans MH-K1 (MH-K1 chitosanase), which also catalyzes the hydrolysis of GlcN-GlcNAc bonds in addition to GlcN-GlcN, has had its chitotetraose [(GlcN)
RESULTS
RESULTS
The MH-K1 chitosanase's (GlcN)
CONCLUSIONS
CONCLUSIONS
Although GH-46 chitosanases vary in the finer details of the subsites defining cleavage specificity, they share similar structural characteristics in substrate-binding, catalytic processes, and potentially in conformational change.
GENERAL SIGNIFICANCE
CONCLUSIONS
The precise binding of a GlcN residue to the -2 subsite is essential for the conformational shift that occurs in all GH-46 chitosanases, as shown by the crystal structures of the apo- and substrate-bound forms of MH-K1 chitosanase.
Identifiants
pubmed: 38158023
pii: S0304-4165(23)00247-7
doi: 10.1016/j.bbagen.2023.130549
pii:
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
130549Informations de copyright
Copyright © 2023 Elsevier B.V. All rights reserved.
Déclaration de conflit d'intérêts
Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.