falciparum infection at day 5 after emergence and dissected 8 days after the infectious blood meal. We then examined the microbial diversity according to the origin of the mosquitoes and investigated putative correlations between the bacterial content and the malaria infection status selleck chemicals Gefitinib by comparing midgut microbiota in P. falciparum-positive and P. falciparum-negative individuals. The adult mosquito midgut microbiota comprises five dominant phyla Proteobacteria, Bacteroidetes, Actinobacteria, Fusobacteria, and Firmicutes and presents some similarities with gut microbial communities from other invertebrate midguts, including mosquitoes [37]�C[44]. Nonetheless, pyrosequencing revealed a higher diversity than more conventional molecular techniques, with an average of 147.64 OTUs (��88.49, at a 0.

04% occurrence threshold) and an estimated richness of 72.27 (��31.70) taxa per field mosquito. Although bacterial richness is greater than previously described in mosquitoes, the vast majority of sequence tags (>90%) felt into few taxa and only 21 bacterial families, and 28 genera had an abundance of >1% in at least one mosquito midgut. Thus, the mosquito midgut is colonized by few dominant bacteria species, probably involved in metabolic functions. We used three different pairs of primers (S1, S2, and S3) to amplify and analyze each midgut sample. The comparison of the bacterial diversity for the three libraries revealed similar patterns; however, the S1 library allowed more detailed identification of the mosquito microbiota.

These data strengthen the previous observation that the SSU rRNA gene clone libraries are biased by the choice of the set of primers used for amplification and thereby distort the revealed biodiversity [45]. To our knowledge, this is the first 454 sequencing analysis where different couples of primers have been used to identify the bacterial diversity in biological samples. The analysis ensured that the primer sets used produced the most accurate view possible of the bacterial content of the mosquito midgut. Proteobacteria represented more than 90% of the bacterial gut content in the mosquitoes from the wild, whereas in laboratory-reared mosquitoes, more than 95% of sequence tags belonged to the Flavobacteria Elizabethkingia spp.

The remaining tags from laboratory mosquitoes were assigned to the members of Gammaproteobacteria GSK-3 (Acinetobacter, Pseudomonas), Firmicutes (Staphylococcus, Streptococcus), and the Alphaproteobacterium Asaia sp. Bacterial richness and diversity seem to be particularly poor in the laboratory mosquitoes. We identified the Elizabethkingia spp. in 68% (19/28) of the field-collected mosquitoes, at low densities (<0.5% of the total bacterial content), suggesting either that the bacterium has developed symbiotic associations with the mosquito midgut or that the bacterium is widespread in nature. The predominance of Elizabethkingia spp.