Bacterial microbiota assemblage in Aedes albopictus mosquitoes and its impacts on larval development

Abstract

Interactions between bacterial microbiota and mosquitoes play an important role in mosquitoes' capacity to transmit pathogens. However, microbiota assemblages within mosquitoes and the impact of microbiota in environments on mosquito development and survival remain unclear. This study examined microbiota assemblages and the effects of aquatic environment microbiota on the larval development of the Aedes albopictus mosquito, an important dengue virus vector. Life table studies have found that reducing bacterial load in natural aquatic habitats through water filtering and treatment with antibiotics significantly reduced the larva-to-adult emergence rate. This finding was consistent in two types of larval habitats examined-discarded tires and flowerpots, suggesting that bacteria play a crucial role in larval development. Pyrosequencing of the bacterial 16S rRNA gene was used to determine the diversity of bacterial communities in larval habitats and the resulting numbers of mosquitoes under both laboratory and field conditions. The microbiota profiling identified common shared bacteria among samples from different years; further studies are needed to determine whether these bacteria represent a core microbiota. The highest microbiota diversity was found in aquatic habitats, followed by mosquito larvae, and the lowest in adult mosquitoes. Mosquito larvae ingested their bacterial microbiota and nutrients from aquatic habitats of high microbiota diversity. Taken together, the results support the observation that Ae. albopictus larvae are able to utilize diverse bacteria from aquatic habitats and that live bacteria from aquatic habitats play an important role in larval mosquito development and survival. These findings provide new insights into bacteria's role in mosquito larval ecology.

Variation in the microbiota across different developmental stages of Aedes albopictus is affected by ampicillin exposure

“…Inconsistent with previous studies suggesting that larvae possess the highest bacterial diversity (Wang et al, 2018), our results reveal that both the bacterial richness and diversity of larvae were lower than those of other stages (Table 1). Taking the sample that was not exposed to the antibiotic as a reference, some unique bacteria in the ampicillin‐treated samples changed in abundance as a result of different concentrations, as detected by the LEfSe analysis (Figure 5; Figures A3 and A4).…”

Natural variation in physicochemical profiles and bacterial communities associated with Aedes aegypti breeding sites and larvae on Guadeloupe and French Guiana

“…Significant differences in the relative abundance of bacteria such as Pseudomonas were recorded between Guadeloupe and French Guiana. Our regression analysis revealed positive correlations with Mg, Ca and conductivity, which is consistent with the higher abundance of these bacteria on Guadeloupe as they are known to be more abundant in environments with high electrical conductivity [66].…”

“…Roseococcus, Pseudomonas and Brevundimonas are strict aerobic bacteria [66,67,68], which could explain the correlations obtained in our study between their abundance and higher dissolved oxygen, as seen on Guadeloupe. Curvibacter was particularly abundant in French Guiana breeding sites.…”

A Gut Commensal Bacterium Promotes Mosquito Permissiveness to Arboviruses

“…Indeed, the previous literature suggests a potential relevance of S. marcescens to dengue prevalence. The presence of S. marcescens was identified in Aedes mosquitoes by 16S rRNA sequencing in Brazil, Panama, and Guangzhou, China, where dengue is endemic (David et al, 2016;Ramirez et al, 2012;Wang et al, 2018). A Serratia species, Serratia nematodiphila, was also identified in the Aedes mosquito gut in a dengue endemic region of Thailand (Thongsripong et al, 2018).…”