Dynamical origins of heat capacity changes in enzyme-catalysed reactions.

ABSTRACT: Heat capacity changes are emerging as essential for explaining the temperature dependence of enzyme-catalysed reaction rates. This has important implications for enzyme kinetics, thermoadaptation and evolution, but the physical basis of these heat capacity changes is unknown. Here we show by a combination of experiment and simulation, for two quite distinct enzymes (dimeric ketosteroid isomerase and monomeric alpha-glucosidase), that the activation heat capacity change for the catalysed reaction can be predicted through atomistic molecular dynamics simulations. The simulations reveal subtle and surprising underlying dynamical changes: tightening of loops around the active site is observed, along with changes in energetic fluctuations across the whole enzyme including important contribution

SUBMITTER: van der Kamp MW 

PROVIDER: S-EPMC5862990 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature