A family 19 chitinase (OsChia1c, class I) from rice, Oryza sativa L., and its chitin-binding domain-truncated mutant (OsChia1c deltaCBD, class II) were produced by the Pichia expression system, and the hydrolytic mechanism toward N-acetylglucosamine hexasaccharide [(GlcNAc)6] was investigated by