title: Carboxymethylated liver alcohol dehydrogenase. Transient kinetic studies and effect of substrate structure on alcohol oxidation.
abstract: 1. The rate constants for NADH binding and dissociation for carboxymethylated alcohol dehydrogenase have been determined and compared to those for the native enzyme. 2. Steady-state and transient kinetic experiments have shown that the hydrogen transfer step is rate-determining for oxidation of ethanol by carboxymethylated alcohol dehydrogenase. The rate constant of 0.19 s-1 is considerably slower than that for the native enzyme. 3. The steady-state parameter, V/[E], was obtained for each of a series of alcohols and correlated with the Taft sigma parameter. The linear relationship obtained indicates that the same step, hydrogen transfer, is rate-determining for all the alcohols. The sigma value obtained is the same as for the native enzyme; the implications of this for the mechanism of hydrogen transfer are discussed.
mesh_terms: D000429:Alcohol Oxidoreductases / Q000378:metabolism*; D000818:Animals; D001665:Binding Sites; D006736:Horses; D007700:Kinetics; D008099:Liver / Q000201:enzymology*; D009243:NAD; D011485:Protein Binding
chemical_list: D009243:NAD; D000429:Alcohol Oxidoreductases