Cyanide ion was studied as an inhibitor of Jack bean urease at 300 K in 30 mmol/L tris buffer, pH 7. The inhibition was investigated by isothermal titration calorimetry (ITC). The extended solvation model was used f...Cyanide ion was studied as an inhibitor of Jack bean urease at 300 K in 30 mmol/L tris buffer, pH 7. The inhibition was investigated by isothermal titration calorimetry (ITC). The extended solvation model was used for CN^- + JBU interaction over the whole range of CN^- concentrations. The binding parameters recovered from the solvation model were attributed to the cyanide ion interaction. It was found that cyanide ion acted as a non-cooperative inhibitor ofurease, and there is a set of 12 ± 0.12 identical and independent binding sites for CN- ions. The dissociation equilibrium constant is 749.99 umol/L. The molar enthalpy of binding is AH= -13.60 kJ mol^-1.展开更多
文摘Cyanide ion was studied as an inhibitor of Jack bean urease at 300 K in 30 mmol/L tris buffer, pH 7. The inhibition was investigated by isothermal titration calorimetry (ITC). The extended solvation model was used for CN^- + JBU interaction over the whole range of CN^- concentrations. The binding parameters recovered from the solvation model were attributed to the cyanide ion interaction. It was found that cyanide ion acted as a non-cooperative inhibitor ofurease, and there is a set of 12 ± 0.12 identical and independent binding sites for CN- ions. The dissociation equilibrium constant is 749.99 umol/L. The molar enthalpy of binding is AH= -13.60 kJ mol^-1.