Fig. 8. Binding of purified myosin-binding fragment of caldesmon to smooth muscle myosin filaments.

Binding was measured in the presence of 10 μm smooth muscle myosin and varied concentrations of purified [¹⁴C]iodoacetamide-labeled myosin-binding fragment. The conditions were the same as described in the legend of Fig. 4. The theoretical curve was calculated assuming a single class of binding sites with an association constant of 9.3 × 10⁴ m⁻¹ and a stoichiometry of 0.96 myosin binding fragment/myosin molecule.