These studies were conducted to investigate the purification and characterization of Kiwifruit protease, and the results obtained were as follows: The protease was purified by ammonium sulfate fractionation, Sephadex G-100 filtration and DEAE-Sephadex A-50 column chromatography and purified enzyme gave a single protein band on polyacrylarnide gel electrophoresis. The specific activity of purified enzyme was 30,10 units/ mg protein and the yield was 7.48. The purified enzyme showed a high affinity for casein and hemoglobin. The optimal pH and temperature for enzyme activity were 7.0 and 45¡É, respectively. The enzyme activity was strongly inhibited by HgCl©ü, MnS0©þ. However, the enzyme was activated by cysteine and EDTA. The Michaelis constant for casein was calculated to be 50.5 mg/ml according to the Line weaver-Burk method, and its molecular weight was determied as 23,500 by polyacrylamide gel electrophoresis.
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