Ketosteroid isomerase provides further support for the idea that enzymes work by electrostatic preorganization.

ABSTRACT: One of the best systems for exploring the origin of enzyme catalysis has been the reaction of ketosteroid isomerase (KSI). Studies of the binding of phenolates to KSI have been taken as proof that the electrostatic preorganization effect only makes a minor contribution to the binding of the real, multiring, transition state (TS). However, our simulation study has determined that the difference between the phenolates and the TS arises from the fact that the nonpolar state of the phenolate can rotate freely relative to the oxyanion hole and thus loses the preorganization contribution. A recent study explored the reactivity of both small and multiring systems and concluded that their similar reactivity contradicts our preorganization idea. Herein, we establish that the available experiments i

SUBMITTER: Kamerlin SC 

PROVIDER: S-EPMC2840163 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature