On the thermodynamic equilibrium between (R)-2-hydroxyacyl-CoA and 2-enoyl-CoA

Abstract

A combined experimental and computational approach has been applied to investigate the equilibria between several α-hydroxyacyl-CoA compounds and their 2-enoyl-CoA derivatives. In contrast to those of their β, γ and α counterparts, the equilibria for the α-compounds are relatively poorly characterized, but qualitatively they appear to be unusually sensitive to substituents. Using a variety of techniques, we have succeeded in measuring the equilibrium constants for the reactions beginning from 2-hydroxyglutaryl-CoA and lactyl-CoA. A complementary computational evaluation of the equilibrium constants shows quantitative agreement with the measured values. By examining the computational results, we arrive at an explanation of the substituent sensitivity and provide a prediction for the, as yet unmeasured, equilibrium involving 2-hydroxyisocaproyl-CoA. © 2010 FEBS.