Thiol – Vitamin K Mechanism in the Clotting of Fibrinogen

Abstract

FROM an investigation into the chemical mechanisms involved in the conversion of fibrinogen into a fibrin gel, it appears that the conversion occurs in at least two stages. The first stage is marked by the liberation of thiol groups in the fibrinogen molecule. The second stage is an oxidation of these thiol groups, which unite to form disulphide linkages with adjacent molecules. It has been found possible to isolate three intermediate products which react when thrombin clots fibrinogen. Thrombin can be divided into two active components which have separate and distinct functions. Neither component will convert, per se, fibrinogen into fibrin; but the mixture of the two will readily clot fibrinogen.