Fig. 3.

Fluorescence polarization titration of [5F]BJC–prothrombin complex with prothrombin fragments. Titration with prothrombin (Pro) fragment 1 (open circles) or fragment 2 (closed circles) was performed in TBS containing 100 nM [5F]BJC and 250 nM prothrombin. Experiments were performed at 25°C and fluorescence polarization measured as described in Materials and Methods. The arrow indicates the polarization value obtained for free [5F]BJC (closed diamonds). Inset: Direct titration of 100 nM [5F]BJC with human prothrombin (Pro) along with the fitted curve calculated with the parameters given in the text.