Biopolymers and cell. 1996; 12 (5): 38 - 45

The role of regulatory arginyl-binding site of plasmine catalytic chain in fibrinogen hydrolysis

E.N.Zolotaryova,N.N.Bugrimenko

The effect ofarginine and fibrinogen Defragment onfibrinogenolysis velocity under the action ofLys77-plasmine and its partially degraded forms was studied. The results obtained revealed the low affinity to arginine of so-called arginyl-binding sites of the catalytic chain compared with arginyl-binding sites of the enzyme non-catalytic chain. At the same time fibrinogen hydrolysis inhibition at Defragment presence was shown to be determined by the site located in the catalytic chain ofLys77- or Lys530-plasmine. This effect was found to occur at the stage of both X-fragments formation and their destruction. The role of catalytic chain regulatory site at some stages offibrinogenolysis is discussed.