Abstract:
:In this paper, we describe the structure of chitinase B from Serratia marcescens, which consists of a catalytic domain with a TIM-barrel fold and a 49-residue C-terminal chitin-binding domain. This chitinase is the first structure of a bacterial exochitinase, and it represents one of only a few examples of a glycosyl hydrolase structure having interacting catalytic and substrate-binding domains. The chitin-binding domain has exposed aromatic residues that contribute to a 55-A long continuous aromatic stretch extending into the active site. Binding of chitin oligomers is blocked beyond the -3 subsite, which explains why the enzyme has chitotriosidase activity and degrades the chitin chain from the nonreducing end. Comparison of the chitinase B structure with that of chitinase A explains why these enzymes act synergistically in the degradation of chitin.
journal_name
Proc Natl Acad Sci U S Aauthors
van Aalten DM,Synstad B,Brurberg MB,Hough E,Riise BW,Eijsink VG,Wierenga RKdoi
10.1073/pnas.97.11.5842keywords:
subject
Has Abstractpub_date
2000-05-23 00:00:00pages
5842-7issue
11eissn
0027-8424issn
1091-6490pii
97/11/5842journal_volume
97pub_type
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