Rewilding the Microbiome of Insectary Reared Mosquitoes: Introducing an Environmental Microbiome to Axenic Aedes aegypti

Abstract

Axenic Aedes aegypti mosquitoes were colonized with bacteria from an environmental water source to compare the midgut microbiota acquired from the wild to the microbiome of insectary reared mosquitoes, specifically over the course of blood meal digestion. 16S rRNA gene sequencing revealed that the diversity, composition, and community structure of the midgut microbiomes were distinct between the insectary and environmental groups, with the environmental microbiomes having a greater diversity and larger temporal shifts over the course of the blood meal. Metagenomic prediction from the 16S rRNA gene sequence data pointed to metabolic processes such as vitamin biosynthesis, fatty acid recycling, and fermentation pathways differentiating the functional potential of the two different microbiomes. To further test if we could identify functional traits that distinguished the two microbiomes we performed a culture-based assay. Culturable bacteria were more abundant in the insectary microbiomes and there was very little overlap in the taxonomy of bacteria recovered from the insectary or environmental groups. The ability of the isolates to lyse blood cells was determined on blood agar plates, and only isolates from the environmental microbiome harbored the ability to perform hemolysis in culture. These data support that the differences in taxonomy observed between the two different microbiomes also results in differences in the functional potential of the community. Thus, this study demonstrates the power of the axenic mosquito model to shed light on the community ecology of the mosquito microbiome, and the potential to better represent the microbiomes of wild mosquitoes in a laboratory setting.

Geographical survey of the mycobiome and microbiome of Southern California glassy-winged sharpshooters

“…While it is unclear why Staphylococcus is lower in abundance in captive GWSS, it is possible that similar to the mycobiome, this change relates to a captive diet or environment. Given the changes in the myco- and microbiomes between captive and wild populations, future work should consider these microbial communities in any future GWSS biocontrol strategies and investigate possible benefits of “rewilding” these communities with environmentally acquired microbes prior to release ( 90 , 91 ).…”

Three Species of Axenic Mosquito Larvae Recruit a Shared Core of Bacteria in a Common Garden Experiment

“…Importantly, the presence of Wolbachia may be important to the biology of these organisms, as Wolbachia are a group of intracellular endosymbionts possessed by a wide range of insects, with potential roles in the reproduction and fecundity of the host organism (e.g. [16][17][18]. Here we show all three species are potentially susceptible to Wolbachia infection, but the infection rates and burdens were significantly higher for Ae.…”

“…Importantly, the axenic model is a blank template that can be used to study the bacteria that colonize the host, opening an avenue for manipulative studies (15). This includes methods to introduce environmental bacteria, in a process we refer to as 'rewilding' the microbiome (16). Here we describe the axenic rearing of two additional species of mosquito, Aedes albopictus (Asian tiger mosquito) and Aedes (Ochlerotatus) triseriatus (Eastern tree hole mosquito).…”

Geographical Survey of the Mycobiome and Microbiome of Southern California Glassy-winged Sharpshooters

“…While it is unclear why Staphylococcus is lower in abundance in captive GWSS, it is possible that similar to the mycobiome, this change relates to a captive diet or environment. Given the changes in the myco-and microbiomes between captive and wild populations, future work should consider these microbial communities in any future GWSS biocontrol strategies and investigate possible benefits of 'rewilding' these communities with environmentally-acquired microbes prior to release [113,114].…”