A Thermodynamic Study on the Binding of Cobalt Ion with Myelin Basic Protein

Abstract

The interaction of myelin basic protein (MBP) from bovine central nervous system with divalent calcium ion was studied by isothermal titration calorimetry at 27 o C in aqueous solution. The extended solvation model was used to reproduce the enthalpies of Co 2+ -MBP interaction over the whole Co 2+ concentrations. The solvation parameters recovered from the solvation model were attributed to the structural change of MBP due to the metal ion interaction. It was found that there is a set of three identical and noninteracting binding sites for Co 2+ ions.The association equilibrium constant is 0.015 μM −1. The molar enthalpy of binding is ΔH = −14.60 kJ mol −1.