Liver alcohol dehydrogenase and ester formation

Residual activity in carboxymethylated liver alcohol dehydrogenase.

The physiological role of liver alcohol dehydrogenase.

1. Yeast alcohol dehydrogenase was used to determine ethanol in the portal and hepatic veins and in the contents of the alimentary canal of rats given a diet free from ethanol. Measurable amounts of a substance behaving like ethanol were found. Its rate of interaction with yeast alcohol dehydrogenase and its volatility indicate that the substance measured was in fact ethanol. 2. The mean alcoho...

Kinetic studies of liver alcohol dehydrogenase.

1. NADH2 prepared by enzymic reduction of pure NAD by the method of Rafter & Colowick (1957), and isolated as the sodium salt, gives higher maxrimum rates of reduction of acetaldehyde with liver alcohol dehydrogenase at pH 6 than a number of commercial preparations of high purity. Maximum values of 2-4 for the extinction ratio E260/E340 and 2% for the proportion of inactive material absorbing a...

The mechanism of quenching of liver alcohol dehydrogenase fluorescence due to ternary complex formation.

Difference fluorescence emission spectra, reciprocal Stern-Volmer plots, and variable excitation wave-lengths have been used to evaluate the selective quenching of the two tryptophan residues/subunit of liver alcohol dehydrogenase. Trp-15, at the surface of the enzyme, is quenched by KI consistent with a collisional mechanism, and has a blue-shifted excitation and red-shifted emission spectrum ...

Kinetic and mechanistic studies of methylated liver alcohol dehydrogenase.

Reductive methylation of lysine residues activates liver alcohol dehydrogenase in the oxidation of primary alcohols, but decreases the activity of the enzyme towards secondary alcohols. The modification also desensitizes the dehydrogenase to substrate inhibition at high alcohol concentrations. Steady-state kinetic studies of methylated liver alcohol dehydrogenase over a wide range of alcohol co...