Fig. 3.
Exosite I is not involved in polyP binding to thrombin. (A) α-thrombin (●) or γ-thrombin (▲), both at 27 pmol were incubated with polyP-zirconia beads in binding buffer with varying NaCl concentrations, after which the flow-through was analyzed for thrombin activity. (B) Thrombin (27 pmol) was preincubated for 30 min with vehicle alone (open bars) or with the C-terminal dodecapeptide of hirudin (solid bars; 5 µg/ml), after which the mixtures were incubated with polyP-zirconia beads in binding buffer containing 50 mM or 1 M NaCl. Thrombin activity was quantified in the flow-through. Data represent mean ± S.D. (n = 3).