Purification and Characterization of a Novel Fibrinolytic Enzyme from Marine Bacterium sp. S-3685 Isolated from the South China Sea.

A novel fibrinolytic enzyme, BSFE1, was isolated from the marine bacterium sp. S-3685 (GenBank No.: KJ023685) found in the South China Sea. This enzyme, with a molecular weight of approximately 42 kDa and a specific activity of 736.4 U/mg, exhibited its highest activity at 37 °C in a phosphate buffer at pH 8.0. The fibrinolytic enzyme remained stable over a pH range of 7.5 to 10.0 and retained about 76% of its activity after being incubated at 37 °C for 2 h. The K and V values of the enzyme at 37 °C were determined to be 2.1 μM and 49.0 μmol min mg, respectively. The fibrinolytic activity of BSFE1 was enhanced by Na, Ba, K, Co, Mn, Al, and Cu, while it was inhibited by Fe, Ca, Mg, Zn, and Fe. These findings indicate that the fibrinolytic enzyme isolated in this study exhibits a strong affinity for fibrin. Moreover, the enzyme we have purified demonstrates thrombolytic enzymatic activity. These characteristics make BSFE1 a promising candidate for thrombolytic therapy. In conclusion, the results obtained from this study suggest that our work holds potential in the development of agents for thrombolytic treatment.