Isolation and Identification of a Chitin Degrading Bacterium Aeromonas SP D5-23 and Properties of Chitinase

Chitin is an abundant biopolymer like cellulose that is rather resistant to degradation. In order to develop a bio-digesting method, soil sample in Qinling Mountain were collected for screening the bacteria with high chitinase activity by method of the transparent circle. The strain D5-23 was isolated and screened out from soil, which was found with amazing chitinase acitivity. The ratio of transient circle and colony circle is no less than 10. The strain was then identified as Aeromonas sp according to the sequences of 16S rDNA and morphological analysis. The enzyme activity was studied further, ,data shows that the optimum temperature was 45°C, which is similar to other Aeromonas sp, wheras the optimum pH is 5 and 9, which is more similar to Vibrio alginolyticus TK-22.