Wehbe Rim, Karaki Aline, Kambris Zakaria
Biology Department, Faculty of Arts and Sciences, American University of Beirut, Beirut, Lebanon.
Front Cell Infect Microbiol. 2025 Aug 12;15:1649545. doi: 10.3389/fcimb.2025.1649545. eCollection 2025.
The gut microbiome plays a major role in promoting organismal homeostasis. Mosquito microbiota influences various aspects of host physiology such as immunity, development and vector competence. Most studies addressing mosquito microbiota consist of microbial diversity profiling and rarely investigate the effects of individual bacteria on host physiology. This remains an important gap of knowledge, especially since not all naturally occurring gut microbes are passive commensals. Here, we identify a pathogenic strain of that causes mortality to both and mosquitoes upon ingestion. In addition, we show that breaches the gut epithelium and gains access to the hemolymph. Parallel to gut damage, we detect a significant increase in the number of proliferative cells in the midguts of fed mosquitoes. Moreover, we find that this bacterium induces a local immune response in the gut leading to the production of anti-microbial peptides. Finally, whole genome sequencing of the isolated strain revealed that it possesses an arsenal of virulence and resistance genes, which provides mechanistic insights into its mosquitocidal activity. This study reports a novel mosquito pathogen and highlights how a bacterial species inhabiting the gut can impact the host's survival and homeostasis.
肠道微生物群在促进机体稳态方面发挥着重要作用。蚊子微生物群影响宿主生理学的各个方面，如免疫、发育和媒介能力。大多数关于蚊子微生物群的研究包括微生物多样性分析，很少研究单个细菌对宿主生理学的影响。这仍然是一个重要的知识空白，特别是因为并非所有自然存在的肠道微生物都是被动共生菌。在这里，我们鉴定出一种致病菌株，摄入后会导致[两种蚊子名称]死亡。此外，我们表明[细菌名称]会破坏肠道上皮并进入血淋巴。与肠道损伤同时发生的是，我们在喂食了[细菌名称]的蚊子中肠中检测到增殖细胞数量显著增加。此外，我们发现这种细菌在肠道中诱导局部免疫反应，导致抗菌肽的产生。最后，对分离菌株的全基因组测序表明，它拥有一系列毒力和抗性基因，这为其杀蚊活性提供了机制上的见解。这项研究报告了一种新型蚊子病原体，并强调了栖息在肠道中的细菌物种如何影响宿主的生存和稳态。
