Oral Infection of Drosophila by Bacteria

The long standing tradition in immunity research in Drosophila has been to inject a dose of bacteria into each individual fly of the experiment using a needle dipped in bacteria. While this method is relatively easy, it leaves much to be desired. Our researrch group has found that this method introduced a highly variable dose of bacteria into each fly. As a remedy to this scenario, a french research group has developed a protocol using an entomopathogenic Pseudomonas bacteria to infect flies orally.

Because of the mechanical and molecular defense mechanisms associated with the Drosophila gut, most pathogens cannot enter through simple ingestion. This fact led to the proliferation of the injection techniques in Drosophila immunity research. Recently however, three Erwinia carotovora bacterial species have been identified which are capable of infecting flies through ingestion. The eperiments were carried out on Drosophila larvae, where 200 larvae were fed an overnight culture of the bacteria. Probably the most useful part of this finding is that expression patterns in response to the Erwinia infection were similar to those seen in respones to infection with other gram negative bacteria. Moreover, when the amount of bacteria eaten was quantified, it was found that the deviation did not exceed that seen with standard injection protocols.

I know it probably only me, but this paper has me excited because it has the potential to make my life much much easier for my final year here.