Kinetic constants of Scheme 1. *P value ≤.05 compared to nfTm; ^**P value ≤.01 compared to nfTm; else, P value >.05. The kinetic constants (for definitions, see Scheme 1) were measured by the sinusoidal length perturbation method at 25°C, ionic strength 200 mM, and pH 7.00. K₂ = k₂/k₋₂ and K₄ = k₄/ k₋₄. The data were individually fitted to the respective equations, averaged, and tabulated with ±SEM. The number of experiments is given in parentheses ( ). ^†Data based on Lu et al. [13].