Purification and characterization of alkaline chitinase from Paenibacillus pasadenensis NCIM 5434

An alkaline chitinase was purified from the bacterium Paenibacillus pasadenensis NCIM 5434 isolated from alkaline littoral soil of Lonar Lake. The chitinase was purified by ammonium sulfate precipitation followed by DEAE cellulose column chromatography. Enzyme was purified by 8.87 folds with 24.96% yield. Molecular characterization through SDS-PAGE analysis showed that it has molecular weight of about ∼35 kDa. The enzyme kinetics studies of purified chitinase revealed the following characteristics, Km 6.25 mg ml(-1) and Vmax 434.78 µM for colloidal chitin as a substrate. The chitinase showed optimum pH 10 and temperature 37 °C. The enzyme exhibited significant activity up to 3% salt concentration, indicating saline nature. Its activity was enhanced with calcium, potassium and magnesium; whereas copper and mercury were found to be inhibitory. Since, it showed antifungal activity against Penicillium and Aspergillus, it could be used as powerful biocontrol agent.