ISSN:
0263-6484
Keywords:
Acetaldehyde
;
ethanol
;
cytosolic fraction
;
mitochondria
;
human liver
;
disulfiram
;
Chemistry
;
Biochemistry and Biotechnology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Medicine
Notes:
The subcellular distribution of aldehyde dehydrogenase activity was determined in human liver biopsies by analytical sucrose density-gradient centrifugation. There was bimodal distribution of activity corresponding to mitochondral and cytosolic localizations. At pH 9.6 cytosolic aldehyde dehydrogenase had a lower apparent Kmapp for NAD (0.03 mmol l-1), than the mitochrondrial enzyme (Kmapp NAD = 1.1 mmol l-1). Also, the pH optimum for cytosolic aldehyde dehydrogenase activity (pH 7.5) was lower than that for the mitochondrial enzyme activity (pH 9.0), and the cytosolic enzyme activity was more sensitive to inhibition by disulfiram in vitro. Disulfiram (40 μmol l-1) caused a 70% reduction in cytosolic aldehyde dehydrogenase activity, but only a 30% reduction in mitochondrial enzyme activity after 10 min incubation. The liver cytosol may therefore be the major site of acetaldehyde oxidation in vivo in man.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cbf.290010107
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