Molecular, cellular and phylogenetic characterization of Wolbachia in Aedes africanus confirms symbionts competition with Pantoea vagans
Wolbachia is an endosymbiotic bacterium that naturally infects several arthropod and nematode species. Wolbachia gained great attention in the last couple of decades, due to its impact on host fitness and the ability of specific Wolbachia strains to interfere with vectorial capacity in mosquitoes or to sterilise insect females. These characteristics have been exploited in pest and vector management and in the control of vector-borne diseases. Wolbachia presence in insect species is variable, with species presenting 100% positive individuals in all sampled populations, and others that present a patchy distribution, with variable prevalences in different populations. Factors that might have an influence on Wolbachia infection rate in insect populations have not yet been investigated in all respects. In addition, there might be limits in the methods used for Wolbachia detection. Through an integrated technical approach, we recently detected and identified Wolbachia in the African bush and forest-associated mosquito Aedes africanus. Investigations on the microbiota of Ae. africanus, and phylogenomics on its Wolbachia, highlighted some peculiarities. First, Wolbachia from Ae. africanus is closer to the wolbachiae of other insects, rather than to those normally found in mosquitoes. Second, metagenomics uncovered a phenomenon of microbial competition between Wolbachia and Pantoea vagans within Ae. africanus.