Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland.
Department of Zoology, University of British Columbia, Vancouver, Canada.
Sci Rep. 2024 Nov 30;14(1):29789. doi: 10.1038/s41598-024-78288-4.
The microbiota of mosquitoes influences many aspects of their biology, including developmental processes, mating and sexual reproduction, immune functions, and refractoriness to pathogens. Here, we considered their role in resistance against insecticides. In particular, we assessed how larval infection of a permethrin-resistant and a sensitive colony of Anopheles gambiae by four strains belonging to three different Pseudomonas species affects several life history traits and the impact of the insecticide on adult mortality. Our data showed that all four Pseudomonas strains persisted in adults until death. The bacteria increased the likelihood that mosquitoes survived 24 h after exposure to permethrin by up to twofold. The impact of the bacteria depended on the bacterial strains and the mosquito colony: in the resistant colony, all bacteria increased survival by about twofold, while in the sensitive colony, only two of the four strains increased survival. The benefit concerning insecticide resistance came with little to no impact on the other traits (i.e., larval mortality, developmental time and adult longevity). Altogether, our results highlight the importance of considering environmental microbial exposure and mosquito microbial communities in epidemiological and vector-control studies, while also suggesting a possible role for Pseudomonas spp. as a symbiont in A. gambiae.
蚊子的微生物群影响其生物学的许多方面，包括发育过程、交配和有性生殖、免疫功能以及对病原体的抵抗力。在这里，我们考虑了它们在抵抗杀虫剂方面的作用。特别是，我们评估了四种属于三种不同假单胞菌属的菌株感染对两种不同生理状态（抗药性和敏感性）的冈比亚按蚊幼虫对几种生活史特征的影响，以及杀虫剂对成虫死亡率的影响。我们的数据表明，所有四种假单胞菌菌株都能在成虫中存活到死亡。细菌使接触拟除虫菊酯 24 小时后蚊子存活的可能性增加了一倍。细菌的影响取决于细菌株和蚊子种群：在抗性种群中，所有细菌使存活率增加了约两倍，而在敏感种群中，只有四种菌株中的两种增加了存活率。关于抗药性的好处几乎没有对其他特征（即幼虫死亡率、发育时间和成虫寿命）产生影响。总的来说，我们的研究结果强调了在流行病学和病媒控制研究中考虑环境微生物暴露和蚊子微生物群落的重要性，同时也表明假单胞菌属可能是冈比亚按蚊的共生菌。
