한국재래간장 발효균 Bacillus subutilis K7 유래의 혈전용해 Protease의 정제 및 특성 = Purification and Characterization of Fibrinolytic Enzyme Produced by Bacillus subtilis K7 Isolated from Korean Traditional Soy Sauce

다국어 초록 (Multilingual Abstract)

An alkaline fibrinolytic protease-producing bacteria was isolated from Korean traditional soy sauce and identified as Bacillus subtilis K7 from the results of analyses of its morphological and physiological properties. API^(?) and Biolog system. The enzyme was purified by 75% ammonium sulfate fractionation, QAE-Sephadex anion and Sp-Sephadex cation exchange column chromatography and Sephadex G-100 gel filtration. The specific activity of the purified enzyme was 233.9 unit/mg protein and the yield of enzyme was 3.8%. The homogeneity of the purified enzyme was confirmed by polyacrylamide gel electrophoresis. Molecular mass of the enzyme was estimated about 21.500 Da by SDS-polyacrylamide gel electrophoresis and gel chromatography. The optimum temperature and pH for the enzyme activity were 40℃ and 9.0. respectively. The enzyme was stable in a pH range 5.0 to 12.0 and 60% of its activity was lost on heat treatment at 50℃ for 20 min. The activity of the purified enzyme was inhibited by the presence of Fe^(2+), Ag^(2+), Cu^(2+), iodoacetate, ethylene diamine tetraacetic acid (EDTA), and trans-1.2-diaminocycloheane-N,N,N`,N`-tetraacetic acid (CDTA). The results indicates that the enzyme requires a metal ion for its enzymatic activity.