Batroxobin is a serine protease derived from the venom of Bothrops atrox. Its molecular weight is approximately 43,000 g/mol−1. This thrombin-like proteolytic enzyme splits the 16 Arg-17 Gly bond in the A(alpha)-chain of fibrinogen, releasing fibrinopeptide A and leading to the clot formation through aggregation of formed of fibrin I monomer or Des-AA-monomer. In contrast to other anti-coagulants, it does not affect the functions of platelets. Hence, Batroxobin is used to determine fibrinogen in plasma, to measure a 'batroxobin clotting time' as a heparin-insensitive parallel to the thrombin time, to investigate dysfibrinogenemia, and to test the contractile system of platelets.