Purification and properties of chitosanase from a mutant of Bacillus subtilis IMR-NK1

• Published in: Enzyme and microbial technology Vol. 32; no. 2; pp. 260 - 267
• Main Authors: Chiang, Chui-Liang, Chang, Chen-Tien, Sung, Hsien-Yi
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 03.02.2003; Elsevier Science
• Subjects: Bacillus subtilis; Biological and medical sciences; Biology of microorganisms of confirmed or potential industrial interest; Biotechnology; Chitooligosaccharides; Chitosanase; Fundamental and applied biological sciences. Psychology; Miscellaneous; Mission oriented research; Properties; Purification; Purification; Properties; Bacillus subtilis; Chitooligosaccharides; Chitosanase; Enzyme; Bacillaceae; Bacillales; Enzymatic activity; Glycosidases; Substrate specificity; Bacteria; Hydrolases; O-Glycosidases; Physicochemical properties
• ISSN: 0141-0229; 1879-0909
• DOI: 10.1016/S0141-0229(02)00275-2

Chitosanase was purified from the crude enzyme preparation of Bacillus subtilis IMR-NK1. The purified chitosanase had an optimal pH of 4.0, an optimal temperature of 45 °C for chitosan hydrolysis. The molecular mass estimated by gel filtration was 36 kDa. Chemical modification agents N-bromosuccinimide (0.05 mM) and p-hydroxymercuribenzoic acid (0.5 mM), and heavy metal ion of Hg 2+ (0.1 mM) significantly or completely inhibited the activity of the enzyme. The enzyme also showed activity for hydrolysis of glycol chitosan and colloidal chitin. In the hydrolysis of chitosans of varying N-acetyl content, the enzyme degraded 60–94% deacetylated chitosan most effectively. End products of chitosan hydrolysis by the enzyme were chitobiose to chitotetraose and some chitooligosaccharides with a longer chain length. For chitooligosaccharides hydrolysis, the smallest of the substrates was a glucosamine tetramer.