鳗弧菌(Vibrio anguillarum)胞外产物中蛋白酶的纯化及其性质

PURIFICATION AND PROPERTY OF EXTRACELLULAR PROTEASES FROM VIBRIO ANGUILLARUM

对鳗弧菌 (Vibrioanguillarum)胞外产物中蛋白酶的纯化方法及其性质进行了研究 .其中 ,蛋白酶的纯化步骤包括 :(1)硫酸铵沉淀 ;(2 )SephadexG 10 0凝胶过滤 ;(3)DEAE Sepharose色谱分离 ;(4)DEAE Cellulose (DE 32 )色谱分离 .经上述纯化步骤得到两种蛋白酶 ,经SDS PAGE分析 ,Mr分别为 37.4× 10 3 和 33.1× 10 3 .以偶氮酪蛋白 (azocasein)作底物测其水解酶活性 ,结果表明二者差别显著 ,前者明显高于后者 .而且 ,Mr37.4× 10 3 的蛋白酶在pH 7～ 10范围内均显示较高活性 ,在 4 0～ 6 0℃范围内稳定性好 .结果表明该蛋白酶是一种金属蛋白酶 .关于该蛋白酶对牙鲆(Paralichtysolivaceus)的毒性作用尚在研究之中 .图 6表 3参

The purification and proteolytic activities of extracellular proteases from Vibrio anguillarum isolated from diseased Paralichtys olivaceus were studied. The purification steps included ammonium sulfate precipitation, Sephadex G 100 chromatography, DEAE Sepharose chromatography and DEAE Cellulose chromatography. Two kinds of proteases were with M r 37.4×10 3 and M r 33.1×10 3 , respectively, but the latter accounted for only a minor fraction of the proteolytic activity for the hydrolysis of azocasein. The M r 37.4×10 3 protease was stable and displayed high proteolytic activity in the range of pH 7～10 and 40～60 ℃. It was strongly inhibited by EDTA and 1,10 phenanthroline. The result indicated that it was a metalloprotease. Its toxicity to Paralichtys olivaceus is still under way. Fig 6, Tab 3, Ref 17