EVIDENCE FOR A WOLBACHIA SYMBIONT IN DROSOPHILA-MELANOGASTER

The bacterial cell division gene, ftsZ, was used as a specific probe t o show the presence of a symbiotic bacterium in two wild type strains of Drosophila melanogaster. Under stringent hybridization conditions w e have shown that the bacterium is transferred to the progeny of these strains from infected mothers and can be eradicated by treatment with the antibiotic tetracycline. We have characterized this bacterium, by amplifying and sequencing its 16S rRNA gene, as being a member of the genus Wolbachia, an organism that is known to parasitize a range of i nsects including Drosophila simulans. In a series of reciprocal crosse s no evidence was found that the symbiont causes cytoplasmic incompati bility (CI) which is known to occur in infected strains of D. simulans . The implications of these findings are discussed.