The intestinal bacterial flora of Glossina palpalis palpalis flies from Cameroon: composition, diversity, relationship with the sampling sites and the infection status of the flies. The intestinal bacterial flora of Glossina palpalis palpalis flies

A meta-taxogenomic analysis has been performed in order to identify the bacterial composition of the microbiome of the tsetse fly, vector of trypanosomes causing Human and Animal trypanosomiasis in sub-Saharan Africa. The rationale was that the microbiome could interfere with the fly’s ability to become infected by the trypanosome that it will further transmit to mammal hosts. Forty Glossina palpalis palpalis flies, infected or not by Trypanosoma congolense, have been sampled in three trypanosomiasis foci in Cameroon. An overall of 144 bacteria have been detected which is unexpected for a strictly hematophagous insect. Most of them identified at the level of their species, and belonged to 104 genera most of them belonging to the Actinobacteria, Bacteroidetes, Firmicutes (mainly Bacilli) and Proteobacteria (alpha, beta and gamma Proteobacteria, mainly Enterobacteriaceae) phyla. Among the prominent representatives were Wigglesworthia, the fly’s obligate symbiont, Serratia, Enterobacter hormaechei; Wolbachia was identified for the first time in G. p. palpalis. However most of the bacteria were either opportunistic human pathogens (several members of the Enterobacter and Acinetobacter genera) or soil/water bacteria. The bacteria were unevenly distributed regarding the sampling sites and with respect to trypanosome infection, or not, of the flies. Further experiments will consist in isolating some of these bacteria expected to be of interest so as to confirm their presence in the flies’ gut as living organisms and to confirm potential ability to modulate Glossina vector competence.