Values of the microscopic rate constants for CO rebinding kinetics after laser photolysis at 20°C.

The rates were determined by fitting the experimental rebinding curves to reaction Scheme 1. The table also shows the second-order rate constants of CO binding that were calculated from the microscopic rate constants and shows the amplitudes and apparent rate constants of CO dissociation.The rates k2 and k-2 are expected to be the same order of magnitude as the rates k3 and k-3. Because the analysis provides unreliable values for k2 and k-2, these parameters were set equal to k3 and k-3, respectively; the latter two parameters are determined with much better precision.As previously observed for the WT protein, the rates kc, k-c, kd, and k-d are also difficult to estimate for these mutants given the small amplitude of the corresponding processes.The rate equations for CO binding have poor sensitivity to kd,r and kd,t, which are held constant to the values determined by the following equation: kOFF,1/2 = kd,r/t × kout /(kout + kg,r/t), where kOFF,1/2 is the dissociation rate constant for CO determined by mixing COMaPgb* with NO.Values of the microscopic rate constants for CO rebinding kinetics after laser photolysis at 20°C.