Role of Chitin Binding Domain of Chitinase A of Streptomyces cyaneus SP-27 in Protoplast Formation from Schizophyllum commune

Abstract

Chitinase A (CHIA) of Streptomyces cyaneus SP-27 forms protoplasts from Schizophyllum commune mycelia when it is combined with α-1,3-glucanase of Bacillus circulans KA-304. An N-terminal chitin-binding domain truncated mutant (CatCHIA), which was expressed in Escherichia coli Rosetta-gami B (DE 3), lost most of its colloidal chitin- and powder chitin-binding activity. The colloidal chitin-hydrolyzing, the powder chitin-hydrolyzing, and the protoplast-forming activities of CatCHIA were lower than those of CHIA, suggesting that the chitin-binding domain contributes to the hydrolysis of chitin in the cell-wall of S. commune.