Factor V

Literature References: Mol wt above 300,000. Participates in the later stages of blood coagulation. Activated by factor X, q.v., and along with Ca2+ and phospholipid forms a complex which converts prothrombin to thrombin, q.q.v. Accelerates the interaction of prothrombin, thromboplastin and Ca2+ ions: Ware, Seegers, Fed. Proc. 7, 131 (1948). Thrombin produces serum Ac-globulin, accelerin, a far more potent accelerator, from plasma Ac-globulin, apparently by catalytic action: Ware et al., Science 106, 618 (1947); Rapaport et al., Blood 21, 221 (1963). Purification: Ware, Seegers, J. Biol. Chem. 172, 699 (1948); Blombäck, Blombäck, Nature 198, 886 (1963). Role in the scheme of blood coagulation: Pavlovsky in Fibrinogen and Fibrin Turnover of Clotting Factors, R. B. Hunter et al., Eds. (Schattauer-Verlag, Stuttgart, 1963) pp 443-454. Proaccelerin deficiency is characterized by prolonged Quick's prothrombin time, and cephalin time, abnormal thromboplastin generation test, abnormal prothrombin consumption, and prolonged whole blood clotting time: Owren in Thrombolytic Activity and Related Phenomena, I. S. Wright et al., Eds. (Schattauer-Verlag, Stuttgart, 1961) pp 387-391. Review: R. W. Colman, Prog. Hemostasis Thromb. 3, 109-143 (1976). Purification, stability, amino acid composition, physical properties of bovine and human factor V: R. W. Colman, R. M. Weinberg, Methods Enzymol. 45B, 107-122 (1976).