Insights into the evolution and divergence of bacterial communities inblood-feeding insects revealed by pyrosequencing

Blood-sucking arthropods are an important component of the transmission pathway of many human and veterinary pathogens and parasites. We used next generation sequencing technology to examine the microbiomes of two such insect species from the same mammalian host at three timepoints in a ten-year period by extracting DNA from ethanol-preserved Hoplopleura hirsuta and Polygenis gwyni specimens and using barcoded universal bacterial primers to PCR-amplify V4 of the 16S rRNA gene for pyrosequencing. The composition of flea and louse communities was significantly different, with P. gywni showing high diversity from multiple phyla including Proteobacteria, Actinobacteria and Bacteroidetes, while H. hirsuta was dominated by a single species of Neisseriaceae. Included in the flea flora were several genera known to harbor human pathogens, including Haemophilus, Salmonella, Yersinia and Acinetobacter. These differences persisted over time and could be related to differences in lifestyle and host-specificity between fleas and lice.