FIG. 3.

Arrhenius plot for the plasma membrane H⁺-ATPase in the presence of different concentrations of trehalose. The points are the calculated V_max at each trehalose concentration and temperature. Trehalose molar concentrations were 0 (○), 0.2 (•), 0.4 (□), 0.5 (▪), 0.6 (▵), and 0.8 (▴). The lines were obtained by linear regression. (Inset) Plot of the energy of activation (E_a) versus trehalose concentration. E_a values were calculated from the line slopes as described by the Arrhenius equation (equation 3), and the line was the result of the fitting as described for Fig. 1C.