Russellysin (EC126.96.36.199, Russell's viper venom factor X activator, RVV-X, blood-coagulation factor X activating enzyme, metalloproteinase RVV-x, Vipera russelli proteinase, Russell's viper blood coagulation factor X activator, RVV-V) is an enzyme. This enzyme catalyses the following chemical reaction
^Lindquist PA, Fujikawa K, Davie EW (March 1978). "Activation of bovine factor IX (Christmas factor) by factor XIa (activated plasma thromboplastin antecedent) and a protease from Russell's viper venom". The Journal of Biological Chemistry. 253 (6): 1902–9. PMID632245.
^Takeya H, Nishida S, Miyata T, Kawada S, Saisaka Y, Morita T, Iwanaga S (July 1992). "Coagulation factor X activating enzyme from Russell's viper venom (RVV-X). A novel metalloproteinase with disintegrin (platelet aggregation inhibitor)-like and C-type lectin-like domains". The Journal of Biological Chemistry. 267 (20): 14109–17. PMID1629211.