Fig. 4.
Inhibition of thrombin by PAI-1 in the presence of vitronectin. The initial rates for thrombin inhibition by PAI-1 in the presence of increasing concentrations of vitronectin are indicated. The rates were measured at a thrombin concentration of 18.6 nmol/L and PAI-1 concentrations of 100 nmol/L (▴), 200 nmol/L (•), or 400 nmol/L (▪), and corrected for the presence of DAPA (370, 4 nmol/L) as described under Experimental Procedures. The lines represent results of a global fit of rates as a function of the bimolecular PAI-1/vitronectin complex as described under Experimental Procedures. Optimal fit was obtained with the values of 51 ± 29 nmol/L for kd and k of 2.1 ± 0.1 × 105 L mol−1 s−1.
