알칼리성 단백질 가수분해효소의 생산능력이 강한 Pseudomoηas sp. SJ-320을 토양으로부터 분리하였으며 효소생산의 최적 배양조건은 배지에 1% casein, 0.2% ammonium chloride, 0.2% $NaH_{2}PO_{4}$, 1% fructose를 혼합첨가하여 $20^{circ}C$, pH 10.0에서 6일간 배양하였을 때 효소생산이 최대로 나타났다. 효소의 최적 작용 pH와 온도는 pH 8.0, $50^{circ}C$ 였으며, pH 7.5-8.5의 범위와 $50^{circ}C$ 이하에서 안정하였다. 급속이온 중 $Mn^{2+}$, $Mg^{2+}$과 $Ca^{2+}$ 등에 의하여 활성이 증대되었으나 $Hg^{2+}$, $Cu^{2+}$ 등에 의하여 효소활성이 저해되었다. 2,4-dinitrophenol, ${varepsilon}-aminocaproic$ acid 처리에 의해 활성이 저해되지 않았으나 ethylenediaminetetraacetic acid와 p-chloromercuribenzoic acid에 의해 활성이 저해되어 효소분자 중 sulfhydryl기가 활성에 어느 정도 관여하는 metallo enzyme으로 추정되였다. 이 효소는 sodium dodecyl sulfate을 제외한 여러 가지 계면활성제에 대해서 강한 저항성을 가지고 있었다.
An alkaline protease producing microorganism was isolated from soil and identified as Pseudomonas sp. SJ-320. The optimum cultivation condition of Pseudomonas sp. SJ-320 for the production of alkaline protease was as follow; 1.0% casein, 0.2% ammonium chloride, 0.2% $NaH_{2}PO_{4}$, 1.0% fructose, $20^{circ}C$, pH 10.0 and 140 h. The optimum pH and temperature for the enzyme activity were pH 8.0 and $50^{circ}C$, respectively. The enzyme was relatively stable at pH 7.5-8.5 and at temperature below $50^{circ}C$. The activity of the partially purified enzyme was inhibited by $Hg^{2+}$ and $Cu^{2+}$ whereas $Mn^{2+}$, $Mg^{2+}$ and $Ca^{2+}$ gave rather activating effects on the enzyme activity. ${varepsilon}-Aminocaproic$ acid and 2,4-dinitrophenol did not inhibit the enzyme, but p-chloromercuribenzoic acid and ethylendiaminetetraacetic acid inhibited the enzyme activity, indicating that reactive sulfhydryl group and metal ion group are required for the enzyme activity. The enzyme was resistant to various detergents, except for sodium dodecyl sulfate.
