The Activation of Alcohols by Liver Alcohol Dehydrogenase: Dependence of Inhibition Upon the pKa Lowering Effect
Liver alcohol dehydrogenase (LADH) is a zinc metalloenzyme that catalyzes the reversible oxidation of alcohols to aldehydes or ketones (Pocker, 1989). The catalytic zinc ion is bound 25 Å from the protein surface at the bottom of a tunnel lined with hydrophobic amino acid residues that stabilize the binding of substrates. For most primary alcohols, including ethanol, the oxidation process follows a compulsory ordered mechanism in which NAD+ binding precedes alcohol binding (Dalziel, 1975). Oxidation occurs within the ternary complex followed by the stepwise release of aldehyde and NADH, respectively.
KeywordsTernary Complex Primary Alcohol Ethanol Oxidation Hydride Transfer Free Alcohol
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