Thermostable Chitosanase from BacMus Characterization

chitin or other P-linked polymers. The enzyme activity was increased about 2.5-fold by the addition of 10 mM Co2+ and 1.4-fold by Mn2+. However, Cu2+ ion strongly inhibited the enzyme. Optimum temperature and pH were 60eC and 6.5, respectively. The enzyme was stable after heat treatment at 800C for 30 min or 70eC for 60 min and fairly stable in protein denaturants as well. Chitosan was hydrolyzed to (GlcN)4 as a major product, by incubation with the purified enzyme. The effects of ammonium sulfate and organic solyents on the action pattern of the thermostable chitosanase were investigated. The amounts of (GlcN)3-(GlcN)6 were increased about 30% (w/w) in DAC 99 soluble chitosan cefitaining 10% arrtmonium sulfate, and (GlcN)i was not produced. The monophasic reaction system consisted of DAC 72 soluble chitesan in 10% EtOH also showed no formatioR of' (GlcN)i, however, the yield of (GlcN)3 -(GlcN)6 was lower than DAC 99 soluble chitosan10% ammonium sulfate. The optimal coficentration of