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.
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.
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*
D007527:Isoenzymes; D012402:Rotenone; D000001:Calcimycin; D000255:Adenosine Triphosphate; D000444:Aldehyde Dehydrogenase; D000079:Acetaldehyde; D008274:Magnesium