The fibrinolytic enzyme, earthworm plasminogen activitor (EPA) or lumbrokinase (LK), was extracted and purified form the earthworm, Eisenia foelide , by a procedure of 30~70%(NH 4) 2SO 4 precipitation, DEAE cellulose exchange chromatograph and Sephadex G 75 gel filtration. And some properties of the enzyme have been studied. EPA’s optimal reaction temperature is 50° C. And after incubating at 50° C for 6 hours, its activity was increased 64%. When the enzyme was incubated in 2mol/L GuHCl and 1% SDS...