Production and some properties of two chitosanases fromBacillus alvei

Bacillus alvei, a potent chitosanase producer, secreted an extracellular chitosan-degrading enzyme in the absence of chitosan. Extracellular secretion of chitosanase reached levels corresponding to 2.3 U/ml after less than two days. The enzyme was purified by precipitation with ammonium sulfate followed by CM-cellulose chromatography. Two chitosanases, chitosanase A and B were purified from the culture fluid. Chitosanase A exhibited substrate specificity for chitosan, while chitosanase B possessed comparable specific activities toward glycol chitin and colloidal chitin. The apparent Km and Vmax, determined at 37 °C and pH 5.6, were 0.8 mg/ml and 2.5 μmol/min, respectively. The enzyme showed an endo-splitting type of cleavage reaction and the end products of chitosan hydrolysis were oligomeric products.