Fibrinolytic Serine Protease Isolated from Earthworm Lampito mauritii

The four enzyme fractions (F 6, 8, 11, 13) with fibrinolytic activities were purified from earthworm Lampito mauritii using the procedures of autolysis, ammonium sulfate fractionation, and column chromatography. The proteolytic activities on the casein substrate of the four iso-enzymes ranged from 53.51 to 71.85 unit/mg. with the rank activity orders of F13 greater than F8 greater than F6 greater than F11. The fibrinolytic activities of the four fractions on the fibrin plates ranged from F11 greater than F6 greater than F13greater than F8. The molecular weights of each iso-enzyme, as estimated by SDS-PAGE, were 100-110 (F6), 75-80 (F8), 45-50 (F11), 35-40 (F13) kDa respectively. For convenience, the proteases are named on the basis of the earthworm species and the protein function, for instance, Lampito mauritii (LaP). Earthworm protease has been applied in several areas such as clinical treatment of clotting diseases, anti-tumor study, environmental protection and nutritional production.