Streptomyces sp. CS624 균주가 생산하는 피브린 분해효소 연구

Abstract

A Fibrinolytic protease (FP624) was purified from Streptomyces sp. CS624, isolated from Korean soil. It produced protease when cultured in a medium containing 1.5% glucose, 1.5% oat meal, 0.45% K2HPO4, and 0.45% NaHPO₄at 28℃. FP624 was purified from a filtrate of Streptomyces sp. CS624 by precipitation with (NH4)2SO4 and gel filtration with Sepharose CL-6B and ion exchange with DEAE-Sepharose CL-6B . SDS-PAGE and fibrin zymography of the purified enzyme showed a single protein band of approximately 28 kDa. The optimal pH and temperature were pH 7.0 and 50℃, respectively. The enzyme was stable between pH 4 and below 40℃. It exhibited fibrinolytic activity, which is stronger than that of plasmin. FP624 hydrolyzes Aα and Bβ-chains of fibrinogen. The activity was enhanced by Ca2+ and Mg2+. Convensely, the activity of FP624 was significantly suppressed by Co2+, Cu2+ and Zn2+ and completely inhibited by Fe2+ and Mn2+. Furthermore, the activity was slightly inhibited by SBTI and PMSF, but significantly inhibited by EDTA, EGTA, TLCK and TPCK. These results suggest that FP624 is a serine metalloprotease with potential application in thrombolytic therapy.