Clotting of Fbg by mixtures of ProT and VWbp(1-263). Increase in turbidity for mixtures of 0.5 mg/mL Fbg and 10 nM thrombin (blue), 10 nM ProT (black), 10 nM ProT·SC(1-325) (red), or 10 nM ProT and VWbp concentrations of 0.1 (a), 0.3 (b), 0.5 (c), or 1 μM (d) (green).