AbstractObjective: To screen fibrinolytic enzyme-producing Bacillus isolates (n=210) and to characterize of thermostable fibrinolytic enzyme from Bacillus amyloliquefaciens EGE-B-2d.1 that had the highest level of fibrinolytic activity together with the highest thermostability.Methods: Firstly, a total of 210 isolates were screened for their fibrinolytic enzyme production. The potent fibrinolytic enzyme producing isolates were evaluated for the thermostability of their fibrinolytic enzymes and one isolate showing prominent fibrinolytic activity was identified as molecular. Fermentation process was carried out on the isolate that had both the highest level of fibrinolytic activity and enzyme thermostability. The thermostable fibrinolytic enzyme from this isolate was then purified and characterized.Results: The fibrinolytic enzyme activities of 21 Bacillus sp. isolates in Nutrient Yeast Salt Medium were found to be in the range of 0.176-1.734 U/ml. The fibrinolytic activity of the enzyme purified from the culture supernatant of Bacillus amyloliquefaciens EGE-B-2d.1 was relatively stable at pH 7.0-11.0 for 24 h and also showed stability at a temperature of 60°C for 60 min. The enzyme degraded the fibrin clots by direct fibrinolysis. The specific activity and the molecular weight of the purified enzyme were estimated to be 44.46 units/mg protein and 30 kD respectively.Conclusion: The thermostable fibrinolytic enzyme from Bacillus amyloliquefaciens EGE-B-2d.1 was purified and characterized. This enzyme might also be used as a natural agent for oral fibrinolytic therapy or thrombosis prevention.
Purification and characterization of a novel, highly potent fibrinolytic enzyme from Bacillus subtilis DC27 screened from Douchi, a traditional Chinese fermented soybean food
