Figure 3.

Temperature-velocity results. (A) Temperature versus velocity curve. Circles and error bars show the experiment data (taken from Miyata et al. (23)); the dashed line is the fitting of the model without weakly facilitated foot release during the power stroke using Eq. 1; the solid line shows the result with weakly facilitated foot release during power stroke using Eq. 3. The effect of weakly facilitated foot release becomes significant at high temperatures, and corrects the deviation from the data. (B) The Arrhenius plots of the foot rates and of the data. For comparison, the rates have been multiplied by corresponding constants to level the logarithm plots at the left end. The whole foot peel-off rate, R_p, has a much larger Arrhenius factor than the off-rate of a single site does because of the multiplying effect shown in Eq. 2. Also, the Arrhenius factor of R_p decreases as temperature increases. (C) The peel-off rate R_p and weakly facilitated release rate R_wf. The weakly facilitated rate becomes significant at ∼25°C, resulting in the attenuation of velocity at high temperatures.