Purification and characterization of a fibrinolytic enzyme and identification of fibrinogen clotting enzyme in a marine green alga, Codium divaricatum

A fibrinolytic enzyme was isolated from a marine green alga, Codium divaric atum, and designated C. divaricatum protease (CDP). This protease effective ly hydrolyzed fibrinogen A alpha chain, while it had very low hydrolyzing e fficiency for B beta and gamma chains. This property was similar to that of alpha-fibrinogenase isolated from snake venom Protease activity peaked at pH 9, and was completely inhibited by diisopropyl fluorophosphate (DFP) and phenylmethylsulfonyl fluoride (PMSF), identifying it as a serine protease. Its molecular form was single polypeptide structure and molecular weight w as estimated as 31 000 by SDS-PAGE. Fibrinogen clotting enzyme was also ide ntified in a fraction by ion-exchange chromatography. Analysis of clots for med by the enzyme and by thrombin by SDS-PAGE showed that the fibrinogen cl otting enzyme would act like thrombin and have high substrate specificity. (C) 2000 Elsevier Science Inc. All rights reserved.