蛹虫草发酵产物新纤溶酶的分离纯化

笔者所在项目组的前期研究发现,蛹虫草深层培养可以产生至少两种纤溶酶.基于此,文中对蛹虫草深层培养产生的纤溶酶的分离纯化展开了研究.采用硫酸铵盐析、Sephadex G-25凝胶色谱、Phenyl-Sepharose HP疏水相互作用色谱、CM-Sepharose FF弱阳离子交换色谱和Superdex 75凝胶色谱对纤溶酶进行分离.最终纯化后的纤溶酶Ⅰ比活力达1467.44U/mg,纯化倍数为36.07,回收率为5.79%.纤溶酶Ⅱ比活力达1681.58U/mg,纯化倍数为41.33,回收率为4.00%.两种纤溶酶经电泳鉴定均达到电泳纯,相对分子质量分别约为28000和32000.

Isolation and Purification of Novel Fibrinolytic Enzymes Obtained from Fermentation of Cordyceps militaris

In their earlier research,the authors have found that at least two kinds of fibrinolytic enzymes can be obtained from the submerged culture of Cordyceps militaris.As a further research,this paper deals with the isolation and purification of these fibrinolytic enzymes by means of ammonium sulfate precipitation,Sephadex G-25 gel filtration chromatography,Phenyl-Sepharose HP hydrophobic interaction chromatography,CM-Sepharose FF weak-cation exchange chromatography and Superdex 75 gel filtration chromatography.After the purification,two kinds of fibrinolytic enzymes are obtained,namely fibrinolytic enzyme I with a specific activity of 1 467.44 U/mg,a purification fold of 36.07 and a recovery of 5.79%,as well as fibrinolytic enzyme II with a specific activity of 1 681.58 U/mg,a purification fold of 41.33 and a recovery of 4.00%.SDS-PAGE results indicate that the two kinds of fibrinolytic enzymes,whose relative molecular mass are respectively about 28 000 and 32 000,are both electrophoretic pure.