Alcohol Dehydrogenase of Drosophila: Interconversion of Isoenzymes

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Science  19 Jan 1968:
Vol. 159, Issue 3812, pp. 324-325
DOI: 10.1126/science.159.3812.324


Isoenzymes of alcohol dehydrogenase extracted from Drosophila melanogaster are interconvertible and can be distinguished by electrophoretic mobility. When adsorbed on diethylaminoethyl cellulose, the faster-moving forms are converted to the slowest-moving form; the latter is converted to the former in the presence of 0.05 molar nicotinamide-adenine dinucleotide, and the conversion is accompanied by the binding of 3.5 moles of the dinucleotide per mole of enzyme. A change in heat stability accompanies the conversion of the slowest form of alcohol dehydrogenase to the fastest form; the latter becomes stable at 45°C. The increased heat stability may indicate that a conformational change in the alcohol dehydrogenase occurs along with the binding of nicotinamide-adenine dinucleotide.