The larval environment strongly influences the bacterial communities of Aedes triseriatus and Aedes japonicus (Diptera: Culicidae)

Authors: JUMA, ELIJAH - University Of Illinois; ALLAN, BRIAN - University Of Illinois; KIM, CHANG-HYUN - University Of Illinois; STONE, CHRISTOPHER - University Of Illinois; Dunlap, Christopher; Muturi, Ephantus

Submitted to: Scientific Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/22/2021
Publication Date: 4/12/2021
Citation: Juma, E.O., Allan, B.F., Kim, C., Stone, C., Dunlap, C.A., Muturi, E.J. 2021. The larval environment strongly influences the bacterial communities of Aedes triseriatus and Aedes japonicus (Diptera: Culicidae). Scientific Reports. 11. Article 7910. https://doi.org/10.1038/s41598-021-87017-0.
DOI: https://doi.org/10.1038/s41598-021-87017-0

Interpretive Summary: Mosquitoes serve as hosts for diverse microbial communities including viruses, bacteria, fungi, and protozoa. Some of these microbes are known to interrupt transmission of mosquito-borne diseases either by shortening the mosquito lifespan or reducing the ability of the pathogen to replicate within the mosquito. As a result, numerous studies are exploring the potential to exploit these microbes as novel tools for controlling mosquito-borne diseases. These microbes are known to be highly dynamic and knowing the factors that shape their diversity and composition is a critical step towards their application in disease control. This study examined how the larval environment and site of collection influences the microbial communities of larval stages of the eastern tree hole mosquito and the Asian rockpool mosquito. Larvae of the two mosquito species were collected from tree hole and waste tire habitats at two study sites in Champaign county, Illinois and their microbial communities characterized. The two mosquito species harbored distinct bacterial communities with the Asian tree hole mosquito hosting more bacterial species than the eastern tree hole mosquito. The bacterial communities of both mosquito species were also strongly influenced by the site of collection and the type of larval habitat where they were collected. These findings improve our understanding of the factors that influence the diversity and composition of mosquito microbiota and provides the framework to investigate how these factors may impact mosquito control by use of symbionts.

Technical Abstract: Mosquito bacterial communities are essential in mosquito biology, and knowing the factors shaping these bacterial communities is critical to their application in mosquito-borne disease control. This study investigated how the larval environment influences the bacterial communities of larval stages of two container-dwelling mosquito species, Aedes triseriatus, and Aedes japonicus. Larval and water samples were collected from tree holes and used tires at two study sites, and their bacteria characterized through MiSeq sequencing of the 16S rRNA gene. Bacterial richness was highest in Ae. japonicus, intermediate in Ae. triseriatus, and lowest in water samples. Dysgonomonas was the dominant bacterial taxa in Ae. triseriatus larvae; the unclassified Comamonadaceae was dominant in water samples from waste tires, while Mycobacterium and Carnobacterium, dominated Ae. japonicus. The two mosquito species harbored distinct bacterial communities that were different from those of the water samples. The bacterial communities also clustered by habitat type (used tires vs. tree holes) and study site. These findings demonstrate that host species, and the larval sampling environment are important determinants of a significant component of bacterial community composition and diversity in mosquito larvae and that the mosquito body may select for microbes that are generally rare in the larval environment.