Abstract
An electrophoretic variant in the LDH (l-lactate:NAD oxidoreductase, E.C.1.1.1.27) of Drosophila melanogaster was observed on starch (or polyacrylamide) gels. This variant was found to exhibit an identical isozymic pattern (three isozymes with a decreasing staining density) on starch gel and map position as the Adh locus. On the other hand, anodal polyacrylamide gel electrophoresis in crude extracts has shown LDH to consist of nine bands and ADH of four bands. We have shown that ADH (Alcohol:NAD oxidoreductase, E.C.1.1.1.1) also oxidizes l(+)-lactate or d(−)-lactate with the NAD, while LDH oxidizes ethanol. By using various genetic and biochemical techniques, we have shown that the observed Ldh electrophoretic variant was not a real one and could be attributed to the presence of ADH. We have called this phenomenon “pseudopolymorphism,” and the problem of enzyme specificity has been examined. The appearance of a band in an assay using lactic acid as a substrate is not sufficient evidence for the presence of LDH. Hence, caution is called for before characterizing an electrophoretic band on a gel as being equivalent to the presence of a genetic locus. Out of the nine electrophoretic zones of activity observed on polyacrylamide gel (or out of the six previously observed) using crude extract, only two (one major and one minor) belong to LDH, as revealed by purified enzyme preparations. Furthermore, purified LDH exhibits activity in two bands on starch gel (out of three observed in crude extracts), which appear in different positions as compared with those of ADH. Finally, one band which responds to the presence of d(−)-lactate but not to l(+)-lactate has been revealed.
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References
Alahiotis, S. (1976). Genetic variation and the ecological parameter “food medium” in cage populations of Drosophila melanogaster Can. J. Genet. Cytol. 18379.
Berger, E. (1971). A temporal survey of allelic variation in natural and laboratory populations of Drosophila melanogaster. Genetics 67121.
Busquets, M., Baro, J., Cortés, A., and Bosal, J. (1979). Separation and properties of the two forms of chicken liver (Gallus domesticus) cytoplasmic malate dehydrogenase. Int. J. Biochem. 10823.
Chambers, G., McDonald, J., McElfresh, M., and Ayala, F. (1978). Alcohol-oxidizing enzymes in 13 Drosophila species. Biochem. Genet. 16757.
Day, T., Hillier, P. and Clarke, B. (1974). Properties of genetically polymorphic isozymes of alcohol dehydrogenase in Drosophila melanogaster. Biochem. Genet. 11141.
Dixon, M., and Webb, E. C. (1971). Enzyme (2nd ed.), Longam Group, London, pp. 204–205.
Gill, P. D. (1978). Survey of isoenzymes in the snail Cepaea nemoralis using different buffer/gel systems in polyacrylamide disk gel electrophoresis. Validity of comparisons and effect of “Nothing Dehydrogenase” activity. Biochem. Genet. 16531.
Gilmour, D. (1961). The Biochemistry of Insects Academic, New York.
Grell, E., Jacobson, K. B., and Murphy, J. B. (1965). Alcohol dehydrogenase in Drosophila melanogaster: isozymes and genetic variants. Science 14980.
Hill, E., Tsernoglon, D., Webb, L., and Banaszak, L. J. (1972). Polypeptide comformation of cytoplasmic malate dehydrogenase from an electron density map at 3.0 Å resolution. J. Mol. Biol. 72577.
Kaplan, N. (1965). Evolution of dehydrogenases. In Bryson, V., and Vogel, H. (eds.), Evolving Genes and Proteins Academic, New York.
Lindsley, D. L., and Grell, E. H. (1967). Genetic variation of Drosophila melanogaster, Carnegie Institution of Washington Publication.
Long, G. L., and Kaplan, N. O. (1968). d-Lactate specific pyridine nucleotide-linked lactate dehydrogenase in animals. Science 162685.
Lowry, O., Roseborough, N., Farr, A., and Randall, R. (1951). Protein measurement with the Folin phenol reagent. J. Biol. Chem. 193265.
Neilands, J. B. (1968). Enzymes of carbohydrate metabolism. In Colowick, S., and Kaplan, N. (eds.), Methods in Enzymology Vol. 1, Academic Press, New York.
Pappas, P., and Rodrick, G. (1971). An electrophoretic study of lactate dehydrogenase isoenzymes, protein, and lipoprotein of D. melanogaster larvae, pupae and adults. Comp. Biochem. Physiol. 40B709.
Rechsteiner, M. (1970). Drosophila lactate dehydrogenase: partial purification and characterization. J. Insect Physiol. 16957.
School, A., and Holzberg, S. (1972). Zone electrophoretic studies on lactate dehydrogenase isozymes in South American Cichlids (teleostei, Percomorphi). Experientia 28489.
Shaw, C. R., and Prasad, R. (1970). Starch gel electrophoresis of enzymes—a compilation of recipes. Biochem. Genetics 4297.
Sieber, F., Fox, D. J., and Ursprung, H. (1972). Properties of octanol dehydrogenase from Drosophila. FEBS Lett. 26274.
Singh, R. S. (1976). Substrate specific enzyme variation in natural populations of Drosophila pseudoobscura. Genetics 82507.
Swanton, M., Smith, D. H., and Shub, D. A. (1975). Synthesis of specific functional messenger RNA in vitro by phage-SPO-1-modified RNA polymerase of Bacillus subtilis. Proc. Natl. Acad. Sci. USA 724886.
Ursprung, H., and Leone, J. (1965). Alcohol dehydrogenase: a polymorphism in D. melanogaster. J. Exp. Zool. 160147.
Zebe, E., and McShan, W. (1957). Lactic and α-glycerophosphate dehydrogenase in insects. J. Gen. Physiol. 40779.
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Onoufriou, A., Alahiotis, S.N. Enzyme specificity: “pseudopolymorphism” of lactate dehydrogenase in Drosophila melanogaster . Biochem Genet 19, 277–299 (1981). https://doi.org/10.1007/BF00504274
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DOI: https://doi.org/10.1007/BF00504274