Cooperative Conformational Transitions Underpin the Activation Heat Capacity in the Temperature Dependence of Enzyme Catalysis.

Many enzymes display non-Arrhenius behavior with curved Arrhenius plots in the absence of denaturation. There has been significant debate about the origin of this behavior and recently the role of the activation heat capacity (Δ) has been widely discussed. If enzyme-catalyzed reactions occur with appreciable negative values of Δ (arising from narrowing of the conformational space along the reaction coordinate), then curved Arrhenius plots are a consequence.