Laboratory colonization by Dirofilaria immitis alters the microbiome of female Aedes aegypti mosquitoes

• DOI: 10.21203/rs.2.23991/v4
• Publication Date: 2020-06-13T02:53:30Z
• Authors: Abdulsalam Adegoke; Erik Neff; Amie Geary; Montana Ciara Husser; Kevin Wilson; Shawn Michael Norris; Guha Dharmarajan; Shahid Karim
• Keywords: DNA, Bacterial; 0301 basic medicine; 570; Dirofilaria immitis; 610; Infectious and parasitic diseases; RC109-216; Mosquito Vectors; Cat Diseases; Mosquitoes; 03 medical and health sciences; Aedes aegypti; Dogs; Aedes; RNA, Ribosomal, 16S; Animals; Dog Diseases; Symbiosis; Phylogeny; Immunology and Infectious Disease; 0303 health sciences; Bacteria; Dog heartworm; Research; Microbiota; Klebsiella oxytoca; Life Sciences; 3. Good health; Cats; Metagenome; Parasitology; Female; Microbiome; Dirofilariasis; Metagenomics

Abstract Background: The ability of blood feeding arthropods to successfully acquire and transmit pathogens of medical and veterinary importance has been shown to be interfered with, or enhanced by, the arthropod’s native microbiome. Mosquitoes transmit viruses, protozoan and filarial nematodes, the majority of which contribute to the 17% of infectious disease cases worldwide. Dirofilaria immitis, a mosquito transmitted by filarial nematodes of dogs and cats, is vectored by several mosquito species including Aedes aegypti.Methods: In this study, we investigated the impact of D. immitis colonization on the microbiome of laboratory reared female A. aegypti. Metagenomic analysis of the V3-V4 variable region of the microbial 16SRNA was used for identification of the microbial differences down to species level.Results We generated a total of 1068 OTUs representing 16 phyla, 181 genera and 271 bacterial species. Overall, in order of abundance, Proteobacteria, Bacteroidetes, Actinobacteria and Firmicutes were the most represented phylum with D. immitis infected mosquitoes having more of Proteobacteria (71%) than uninfected mosquitoes (56.9%). An interesting finding in this study is the detection of Klebsiella oxytoca in relatively similar abundance in infected and uninfected mosquitoes, suggesting a possible endosymbiotic relationship, and has been previously shown to indirectly compete for nutrients with fungi on domestic housefly eggs and larva. While D. immitis colonization has no effect on the overall species richness, we identified significant differences in the composition of selected bacteria genus and phylum between the two groups. We also reported distinct compositional and phylogenetic differences in the individual bacteria species when commonly identified bacteria were compared. Conclusions In conclusion, this is the first study to the best of our knowledge to understand the impact of a filarial infection on the microbiome of its mosquito vector. Further studies are required to identify bacteria species that could play an important role in the mosquito biology. While the microbiome composition of A. aegypti mosquito have been previously reported, our study shows that in an effort to establish itself, a filarial nematode modifies and alters the overall microbial diversity within its mosquito host.