蚯蚓纤溶酶底物特异性

蚯蚓纤溶酶是具有较强溶栓作用的丝氨酸蛋白酶，为研究蚯蚓纤溶酶在溶栓的同时是否对其他血液蛋白有破坏作用，本实验以一些血液功能蛋白为底物，用蚯蚓纤溶酶在体外对其进行水解，采用SDS—PAGE检测水解前后底物成分的变化。结果显示，蚯蚓纤溶酶短时间内能完全水解纤维蛋白和纤维蛋白原，长时间作用下能部分水解牛血清白蛋白和人免疫球蛋白重链，不水解牛血红蛋白、牛血超氧化物歧化酶和牛凝血酶原。表明蚯蚓纤溶酶对血栓成分具有较强的识别和水解能力，而对其他血液蛋白作用微弱，说明蚯蚓纤溶酶作为药物使用时具有较强的溶栓和预防血栓形成的作用，且副作用较小。

Substrate Specificity of the Fibrinolytic Enzymes from Earthworm

It was well known that Earthworm Fibrinolytic Enzymes(EFE) were alkaline proteases with potent thrombolytic activity. To elucidate EFE's hydrolysis of other functional proteins in blood, we hydrolyzed fibrinogen, bovine serum albumen,immunoglobulin, superoxide dismutase,bovine hemoglobin and bovine thrombinogen in vitro by EFE, respectively, and the changes of the substrates were detected by SDS-PAGE. It was found that EFE completely hydrolyzed fibrin and fibrinogen, forming soluble fragments within two hours, however, and it partially hydrolyzed bovine serum albumen and the heavy chain of immunoglobulin if the reaction time was prolonged, while it basically did not hydrolyze superoxide dismutase, bovine hemoglobin and bovine thrombinogen. The results show that EFE has more cleavage specificity and ability for the components of thrombus than for other blood proteins, and it has little side-effect when used as preventive and therapuetic medcine.