title: Acetaldehyde oxidation in rat liver mitochondria, action of Mg2+, ATP and rotenone on acetaldehyde oxidation in intact mitochondria, and on some purified aldehyde dehydrogenase isozymes.
abstract: In intact rat liver mitochondria acetaldehyde is oxidized by three functionally distinct dehydrogenase systems. Two of these reduce intramitochondrial nicotinamide adenine dinucleotide (NAD): one is operative with micromolar acetaldehyde concentrations and is stimulated by Mg2+, the other is operative with millimolar acetaldehyde concentrations and is stimulated by adenosine 5'-triphosphate (ATP). The third system reduces added NAD and is stimulated by rotenone. Connected to these systems, three aldehyde dehydrogenase isozymes (ALDH) have been purified: a low-Km ALDH activated by Mg2+, a high-Km ALDH activated by ATP and Mg2+, a high-Km ALDH activated by rotenone. The properties of some isozymes are affected by detergents. Thus, deoxycholate augments the stimulation of low-Km isozyme by Mg2+ and confers sensitivity to Mg2+ and ATP on one of the high-Km isozymes. A fourth isozyme has been purified. Its affinity for acetaldehyde is so low that it is very unlikely that acetaldehyde is the physiological substrate.
mesh_terms: D000079:Acetaldehyde / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000494:pharmacology*; D000444:Aldehyde Dehydrogenase / Q000302:isolation & purification / Q000378:metabolism*; D000818:Animals; D000001:Calcimycin / Q000494:pharmacology; D005260:Female; D007527:Isoenzymes / Q000302:isolation & purification / Q000378:metabolism*; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology*; D008297:Male; D008930:Mitochondria, Liver / Q000187:drug effects / Q000378:metabolism*; D010084:Oxidation-Reduction; D051381:Rats; D011919:Rats, Inbred Strains; D012402:Rotenone / Q000494:pharmacology*
chemical_list: D007527:Isoenzymes; D012402:Rotenone; D000001:Calcimycin; D000255:Adenosine Triphosphate; D000444:Aldehyde Dehydrogenase; D000079:Acetaldehyde; D008274:Magnesium