A gastric alcohol dehydrogenase in the baboon: purification and properties of a 'high-Km' enzyme, consistent with a role in 'first pass' alcohol metabolism.
The major isozyme of alcohol dehydrogenase in baboon stomach, ADH3, has been purified to homogeneity and characterized with a range of alcohol and aldehyde substrates. Using kcat/Km values as an indication of substrate efficacy, medium-chain length aliphatic alcohols and aldehydes were identified as the preferred substrates. ADH3 showed 'high-Km' properties with respect to ethanol, and is expected to significantly contribute to 'first-pass' metabolism of alcohol. The enzyme exhibited more than two orders of magnitude higher turnover of substrate than the baboon liver 'low-Km' ADH, and may play a role in the rapid metabolism of a wide range of ingested alcohols in the diet.
Algar
E M
EM
Division of Science and Technology, Griffith University, Brisbane, Australia.
VandeBerg
J L
JL
Holmes
R S
RS
D000426:Alcohol Dehydrogenase / Q000302:isolation & purification* / Q000502:physiology; D000818:Animals; D004591:Electrophoresis, Polyacrylamide Gel; D000431:Ethanol / Q000493:pharmacokinetics*; D007525:Isoelectric Focusing; D007527:Isoenzymes / Q000302:isolation & purification* / Q000502:physiology; D007700:Kinetics; D008099:Liver / Q000201:enzymology; D010215:Papio; D013270:Stomach / Q000201:enzymology*
D007527:Isoenzymes; D000431:Ethanol; D000426:Alcohol Dehydrogenase