Bacillus sp. SH-5와 그것의 알칼리성 단백질 분해효소의 특성에 관한 연구

Characterization of Bacillus sp. SH-5 and Its Alkaline Protease

For selection of bacteria that produce protease, well growing bacteria were isolated from Korean Soybean paste in the media containing 1% skim milk. Out of about 100 colonies which showed protease activity with a clear zone on the media containing 1% skim milk, a colony producing the largest amount of protease was selected. The isolated and selected strain SH-5 was an aerobic, spore-forming, Gram positive, motile, rod-shaped bacterium. Considering its characteristics, the bacterium belongs to genus Bacillus. The optimum pH for growth and alkaline protease production of the bacterium was 7.0, and it grew at range of pH 6.1~9.4. The optimum temperature for its growth and the alkaline protease production was 37°C The enzyme from this strain was most active at pH 9 in casein containing buffer and stable at a range pH 6.0~12.0 for 30 min. The optimum temperature for the enzyme action was 60°C in the presence of calcium ion.