Heinstra, P.W.H., Eisses, K.T., Schoonen, W.G.E.J., Aben, W., de Winter, A.J., van der Horst, D.J., van Marrewijk, W.J.A., Beenakkers, A.M.T., Scharloo, W., Thorig, G.E.W. (1983). A dual function of alcohol dehydrogenase in Drosophila.  Genetica 60(2): 129--137.

FBrf0039416

Research paper

Alcohol dehydrogenase (ADH) of Drosophila not only catalyzes the oxidation of ethanol to acetaldehyde, but additionally catalyzes the conversion of this highly toxic product into acetate. This mechanism is demonstrated by using three different methods. After electrophoresis the oxidation of acetaldehyde is shown in an NAD-dependent reaction revealing bands coinciding with the bands likewise produced by a conventional ADH staining procedure. In spectrophotometric measurements acetaldehyde is oxidized in an NAD-dependent reaction. This activity is effectively inhibited by pyrazole, as specific inhibitor of ADH. By means of gas chromatographic analysis a quick generation of acetate from ethanol could be demonstrated. Our conclusion is further supported by experimental results obtained with either purified ADHF enzyme or genotypes with or without ADH, aldehyde-oxidase, pyridoxal-oxidase and xanthine-dehydrogenase activity. These results are discussed in relation to ethanol tolerance in the living organism in particular with respect to differences found between ADH in Drosophila melanogaster and D. simulans, and in relation to the possible implications for the selective forces acting on ADH-polymorphism.