内生多黏类芽孢杆菌纤溶酶的纯化及其体外溶栓作用

植物内生菌株 EJS-3 发酵液经离心除菌，硫酸铵分级沉淀，Hiprep phenyl FF 疏水层析，RESOURCEM Q离子交换层析和Sephacryl S-300HR 凝胶过滤，获得电泳纯的多黏芽孢杆菌纤溶酶(PPFE-I)，聚丙烯酰胺凝胶电泳(SDS-PAGE)测定其分子质量为63kD，高效液相色谱法(HPLC)鉴定其纯度为94.1%。每升发酵液中可获得1.6mg 活性蛋白，每毫克蛋白活力达2096IU，纯度提高了14.5 倍，回收率为3.3%。纯化后的纤溶酶PPFE-I 具有明显的体外溶栓作用。

Purification and Thrombolytic Effect in vitro of a Novel Fibrinolytic Enzyme Produced by Endophytic Bacterium Paenibacillus polymyxa EJS-3

Endophytes are a very important resource of microorganisms with potential application values. A novel fibrinolytic enzyme (PPFE-I) was purified from the fermentation supernatant of endophytic bacterium Paenibacillus polymyxa EJS-3 by the following procedure including ammonium sulfate precipitation, Hiprep phenyl FF hydrophobic chromatography, RESOURCEMQ ion exchange chromatography and Sephacryl S-300HR gel filtration. The apparent molecular mass of PPFE-I was estimated to be 63 kDa by SDS-PAGE analysis. The purity of PPFE-I was 94.1% determined by HPLC. Using the above procedure, 16 mg of active proteins were obtained from 1 L of the fermentation supernatant of Paenibacillus polymyxa EJS-3 and a 14.5-fold increase in the specific activity of PPFE-I was achieved and the activity recovery was 3.3%. Meanwhile, the final purified product had good thrombolytic activity in vitro.