Action pattern of Streptomyces griseus chitinase on partially N-acetylated chitosan.

Oligosaccharides produced during the course of the hydrolysis of 25% N-acetylated chitosan by Streptomyces griseus chitinase were fractionated by CM-Sephadex C-25 and Toyopearl HW-40F column chromatographies. Sugar compositions and sequences of main oligosaccharides were identified by N-acetylation, exo-splitting with beta-GlcNAcase and beta-GlcNase, and nitrous acid degradation. In addition to N-acetylated saccharides, GlcNAc, (GlcNAc)2, and (GlcNAc)3, hetero-chitooligosaccharides such as GlcN.GlcNAc, GlcN.GlcNAc.GlcNAc, GlcN.GlcN.GlcNAc, GlcN.GlcNAc.GlcNAc.GlcNAc, GlcNAc.GlcN.GlcNAc.GlcNAc, GlcN.GlcNAc.GlcN.GlcNAc, and GlcN.GlcN.GlcNAc.GlcNAc were identified. These results indicate that Streptomyces griseus chitinase specifically cleaves the N-acetyl-beta-D-glucosaminidic linkages in partially N-acetylated chitosan.