D3213: Investigating behavioral responses of Drosophila melanogaster to microbial volatiles

Drosophila fruit flies exhibit an incredibly strong, innate repulsion to volatiles (odours) produced by fungi present in decomposing fruit. In particular, the chemicals geosmin and 1-octen-3-ol function as potent oviposition (egg laying) deterrents to multiple species of Drosophila fruit flies. These flies use such odors to help identify areas unsuitable for egg development and larval survival – fruit which is overrun with fungi provides a poor food source, and may be lethal to developing larvae. Streptomyces bacteria, which produce many of the same metabolites as fungi, may be laboratory-cultured and genetically modified to amplify production of the key metabolites, including volatiles which influence insect behavior. In this study, we assay a series of Streptomyces strains to identify key odorants which function as repellents. Results will review differential behavioral responses and confounds between behavioral assay techniques, as well as discuss key volatiles which elicit repellent behavior.