Student Research Projects

The Influence of Wolbachia on the Metagenome of the Common Fruit Fly, Drosophila melanogaster

Student Amanda Hyre ‘14
Faculty Mentor(s)
Department Biology
Course Biology 489: Research Methods in the Natural Sciences


Wolbachia are obligate intracellular prokaryotic endosymbionts estimated to be present in 20 – 70 percent of arthropod species. It is known to convey a variety of effects upon the host, exhibiting both reproductive and non-reproductive effects. In this study, we sought to demonstrate whether Wolbachia alters the metagenome of the common fruit fly, Drosophila melanogaster, as little work has been published in this area. To do this, we extracted whole genomic DNA from four sample groups – females harboring Wolbachia, males harboring Wolbachia, females free of Wolbachia, and males free of Wolbachia – and analyzed the results of 16S rRNA gene sequencing. We analyzed twenty metagnomic analyses consisting of five flies each. We examined prokaryotic genera present in concentrations of at least one per cent in one or more of the samples. We then analyzed the data and made three different comparisons at the genus level. Initially, we used a one way ANOVA to find statistically significant variation in prokaryotic genera between all four sample groups. We then used a t-test to compare flies harboring Wolbachia with those not harboring the endosymbiont. The last analysis was a comparison of male and female flies, regardless of infection status. The results yielded statistically significant variation in the diversity of multiple prokaryotic genera in all three comparisons. Most notably, Staphylococci, Streptococci, and Anaerococci tended to be more prevalent in uninfected flies, regardless of gender. The metagenomic analysis will need to be verified through traditional culture-dependent methods. It is unclear at this time how and why the presence of Wolbachia may alter the microflora of fruit flies and what effect this may have on their biology.


Project won best poster at VWC's annual 2014 Undergraduate Research Symposium, Division of the Natural Sciences and Mathematics