Purification and Characterization of Kiwifruit Protease

키위열매 Protease 의 추출 정제 및 그 특성에 대하여

  • Kim, Bok-Ja (Dept. of Food and nutrition, Dae Jeon Junior College)
  • 김복자 (대전실업전문대학 식품영양과)
  • Published : 1989.08.01

Abstract

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 polyacrylamide 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 $45^{\circ}C$, respectively. The enzyme activity was strongly inhibited by $HgCl_2,\;MnSO_4$. However. the enzyme was activated by cysteine and EDTA. The Michaelis constant for casein was calculated to be 50.5mg/ml according to the Line weaver-Burk method, and its molecular weight was determied as 23,500 by polyacrylamide gel electrophoresis.

Keywords

kiwifruit protease;fractionation of mlase;purification of protease;characterization of protease