ALKALOID METABOLISM BY CYTOCHROME-P-450 ENZYMES IN DROSOPHILA-MELANOGASTER

The cytochrome P-450 family of enzymes is the primary means of foreign compound detoxification in virtually all organisms, Cytochrome P-450s have been strongly implicated in the metabolism of cactus alkaloids, and consequently, the observed patterns of host plant utilization by c actophilic species of Drosophila in the Sonoran Desert. The current st udy looked for evidence of alkaloid-metabolizing P-450 enzymes in a no n-cactophilic species, D. melanogaster. The results of in vitro metabo lism assays indicate the presence of a phenobarbital-inducible P-450 i n adult D. melanogaster which is capable of metabolizing alkaloids. P- 450 quantification data suggest that the enhanced level of metabolism is not the result of an overall increase in total P-450 content, Resul ts from larval viability and adult longevity studies indicate that D. melanogaster's in vitro activity does not produce an enhanced in vivo tolerance of alkaloids,