Fig. 1.

Dehydrogenase activities of BceC and its Y10F mutant. (A) Activity relative to the pH of the medium at 30°C. (B) Activity relative to the temperature of the medium at pH 8.7. (C) Plot of the first three values of ln(k/T) versus 1/T (the ignored remaining values correspond to degraded conformations of the enzyme at higher temperatures) allows an estimation of ΔH^‡ (enthalpy of activation) and ΔS^‡ (entropy of activation) according to the Eyring-Polanyi equation: ln(k/T) = −ΔH^‡/R × 1/T + ln(k_B/h) + ΔS^‡/R, where k_B is the Boltzmann constant, h is Planck's constant, and R is the gas constant (18, 20). Bars represent maximal intervals of (two or three) the measurements replicates.