The mechanism of the fibrinogen-thrombin reaction.

Abstract The kinetics of the thrombin-catalysed release of fibrinopeptide A from fibrinogen, modified fibrinogen and various fragments of fibrinogen has been investigated in an attempt to elucidate the structural elements of fibrinogen which define its interaction with thrombin. These elements have been found to be contained within the structure formed by the first 51 amino acid residues of the Aα-chain. It is proposed that the binding which is of fundamental importance takes place within the sequence 1–23 of this chain and may even be localised to the sequence 8–16. This binding is strengthened, either directly or indirectly, by structures within the sequence 34–44 and to a lesser extent by structures within the sequence 45–51.