Mitteilung Z
J Clin Chem Clin Biochem. 1976 Jun;14(6):245-51.
In this paper we discribe a method for the isolation of trypsin inhibitors from the tentacles of the annelid Sabellastarte indica Savigny. These inhibitors - now homogeneous in their molecular weight - can be characterised by sodium dodecylsulfate-acrylamide gel-electrophoresis, in their inhibitory activity towards trypsin, plasmin and chymotrypsin. The inhibitors from Sabellastarte indica possess a stoichiometric binding relation of 2:1 for trypsin, lysine being the amino-acid in the reactive centre of the inhibitor responsible for interaction with trypsin. The reactive centre for trypsin is not identical with the reactive centre which binds chymotrypsin and does not influence the binding of chymotrypsin. These newly described inhibitors are therefore multiheaded, a type not previously described for invertebrates.