Sun F, Liu E, Zhang Y
Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071.
Wei Sheng Wu Xue Bao. 1997 Oct;37(5):397-400.
The production and properties of protease from Bacillus sphaericus strain C3-41 were reported in this paper. It was found out that the secrete of extracellular protease began at the exponential phase, reached a maximum at the early phase of sporangium and then decrease rapidly. The production conditions of the protease have been studied. The protease preparation was purified by salting out with ammonium sulfate and by chromatography fractionating on Sephadex G-100. The purified enzyme have a specific activity of 6741.5 U/mg protein and a molecular weight of 42,000. The optimal activities of the protease were around pH11.0 and at 4 degrees C respectively. The enzyme was stable at pH5.0-12.0. The proteolytic activity was inhibited by phenylmethylsulphony fluoride (PMSF) and EDTA, but not by IAA, SA and DTT. The activity was inhibited in the presence of Al3+, Hg2+, Fe3+, Cu2+ and Fe2+. The enzyme was sensitive to higher temperature, but was quite stable in the presence of Ca2+.
本文报道了球形芽孢杆菌C3 - 41菌株蛋白酶的产生及性质。发现胞外蛋白酶的分泌始于指数期，在芽孢形成早期达到最大值，然后迅速下降。对蛋白酶的产生条件进行了研究。蛋白酶制剂通过硫酸铵盐析和Sephadex G - 100柱层析进行纯化。纯化后的酶比活性为6741.5 U/mg蛋白质，分子量为42000。该蛋白酶的最佳活性分别在pH11.0左右和4℃。该酶在pH5.0 - 12.0范围内稳定。蛋白水解活性受苯甲基磺酰氟（PMSF）和乙二胺四乙酸（EDTA）抑制，但不受吲哚乙酸（IAA）、水杨酸（SA）和二硫苏糖醇（DTT）抑制。在Al3 +、Hg2 +、Fe3 +、Cu2 +和Fe2 +存在时活性受到抑制。该酶对较高温度敏感，但在Ca2 +存在时相当稳定。
