Electronic Effects in Horse Liver Alcohol Dehydrogenase Catalysis.

Abstract

Kinetic studies of the horse liver alcohol dehydrogenase-catalyzed reduction of benzaldehyde and a series of para-substituted benzaldehyde compounds have been made. There was no apparent deviation from the ordered mechanism postulated for the reaction with any of the substrates examined. The values of the kinetic constants 0 and [PHI] 1 were independent of the nature of the aldehyde substrate. The values of 1/[PHI] 2 increased with the increasing electron-withdrawing power ([sigma] value) of the para-substit-uent. The results are consistent with the postulated reaction mechanism involving the transfer of a hydride ion to or from an alcoholate ion intermediate.