From the venom of the Taipan snake (Oxyuranus scutellatus). Converts prothrombin to thrombin. Specificity is similar to that of Factor Xa (EC 18.104.22.168). However, unlike Factor Xa this enzyme can cleave its target in the absence of coagulation Factor Va. Activity is potentiated by phospholipid and Ca2+ which binds via γ-carboxyglutamic acid residues. Similar enzymes are known from the venom of other Australian elapid snakes, including Pseudonaja textilis textilis, Oxyuranus microlepidotus and Demansia nuchalis affinis.
Walker, F.J., Owen, W.G. and Esmon, C.T. Characterization of the prothrombin activator from the venom of Oxyuranus scutellatus scutellatus (taipan venom). Biochemistry19 (1980) 1020–1023. [PMID: 6986908]
Speijer, H., Govers-Reimslag, J.W., Zwaal, R.F. and Rosing, J. Prothrombin activation by an activator from the venom of Oxyuranus scutellatus (taipan snake). J. Biol. Chem.261 (1986) 13258–13267. [PMID: 3531198]
[EC 22.214.171.124 created 1978 as EC 126.96.36.199, transferred 1992 to EC 188.8.131.52, modified 2010, modified 2011]