Purification and properties of chitinase from Arthrobacter sp NHB-10

A chitinase was purified from the culture filtrate of nigeran-degrading Arthrobacter sp. NHB-10 by precipitation with ammonium sulfate and column chromatographies on DEAE-Sephadex A-50 and Superose 12. The final preparation was homogenous in polyacrylamide gel electrophoresis. The molecular weight of the purified enzyme was 30,000 and its isoelectric point was 6.8. The optimum pH and temperature for the enzyme activity were 5.0 and 45 degrees C, respectively. The enzyme was stable from pH 3 to 7 and up to 55 degrees C. The enzyme activity was inhibited by Hg2+ and p-chloromercuribenzoic acid. Two internal amino acid sequences of the enzyme were AGPQLLTGW and IGGVMT.