[New protease-inhibitors with broad specificity in the polychaet Sabellastarte indica (Savingny), I (author's transl)].

In this paper we describe new and so far unknown protease inhibitors present in the tentacles of the annelid Sabellastarte indica Savingny. At least five different isoinhibitors with inhibitory activity towards trypsin, plasmin, chymotrypsin and kallikrein can be separated electrophoretically. Our protease inhibitor active material differs from the other well known protease inhibitors found in invertebrates in its high molecular weight, in that it is heat-labile and in the occurrence of the isoelectric point in the weakly acid region. On the other hand, the new protease inhibitors have some similarities to the soybean inhibitor described by Kunitz, and to ovomucoid. We also discuss the possibility that these inhibitors may influence the fibrinolytic system.