Purification and Properties of Protease from Thermophilic Actinomyces

고온성 방선균이 생산하는 단백질 분해효소의 정제와 특성

Microbial protease has been interesting due to the biological roles in the producing microorganism. A thermophilic Actinomyces produing protease was isolated from soil. The optimal medium composition and culture conditions for maximum protease production was as follows 0.5% soluble starch, 0.5% yeast extract. 0.1% K2HPO4, 0.05% CaCl2, initial pH 8.0 at 50$^{\circ}C$ for 48hours. The protease was purified by the procedure of ammonium sulfate precipitation, anion exchange chromatography(LC), DEAE high performance liquid chromatography and GPC HPLC. The purification fold of the purified enzyme was increased about 22.6. The optimal pH and temperature for reaction of the purified enzyme were 7.5 and 60$^{\circ}C$. The purified enzyme was stable for the pH range from 6.0 to 8.5, but was unstable when treated at 80$^{\circ}C$ for 10 minutes. The activity of the enzyme was inhibited by Ag+ and Cu2+.