背景:白纹伊蚊是登革热等病原体的重要媒介,Zika,和基孔肯雅病毒.虽然杀虫剂是控制蚊虫的主要手段,它们的广泛和过度使用导致了Ae的耐药性增加。全球白纹。肠道共生细菌被认为在昆虫生理学中起着潜在的作用。可能与蚊子对杀虫剂的代谢抗性有关。
方法:我们研究了共生细菌在Ae耐药性发展中的作用。通过比较对溴氰菊酯敏感和对溴氰菊酯耐药的人群之间的肠道共生细菌,白纹伊蚊。从野外收集的幼虫中饲养成虫。使用0.03%和0.09%的溴氰菊酯对敏感和抗性蚊子进行筛选,分别,在世界卫生组织(WHO)管生物测定的基础上。使用5×LC50(死亡率为50%时的致死浓度)和20×LC50浓度的溴氰菊酯筛选敏感和抗性野外收集的幼虫,分别。实验室菌株溴氰菊酯敏感的成虫和幼虫用作对照。使用磁珠方法提取来自这些蚊子的肠道样品的DNA。使用BGISEQ方法对细菌16SrDNA进行测序。我们使用四种不同的培养基从成虫和幼虫蚊子中分离和培养肠道微生物:LuriaBertani(LB),脑心输液(BHI),营养琼脂(NA),和沙门氏菌志贺氏菌(SS)。
结果:测序显示,田间抗性幼虫的肠道微生物多样性明显高于田间敏感性和实验室敏感性幼虫(P<0.01)。相反,田间抗性和田间敏感性成年人的肠道微生物多样性明显低于实验室敏感性成年人(P<0.01)。在物种层面,从田间抗性幼虫和成虫的肠道中分离出25和12种细菌,分别。黄杆菌属的丰度。,Gemmobacterspp。,和Dysgonomonasspp。与敏感幼虫相比,田间抗性幼虫的肠道明显更高(均P<0.05)。此外,黄杆菌属的丰度。,泛菌属。,和气单胞菌属。与敏感成年人相比,田间抗性成年人的肠道明显更高(均P<0.05)。抗性幼虫和成年蚊子之间的优势和差异发生的微生物也不同。这些发现表明Ae的肠道共生细菌。白纹伊蚊成虫和幼虫可能在溴氰菊酯抗性中起着不同的作用。
结论:这项研究为进一步探索肠道微生物在杀虫剂抗性中的作用机制提供了经验基础。可能为蚊子控制策略开辟新的前景。
BACKGROUND: Aedes albopictus is an important vector for pathogens such as dengue, Zika, and chikungunya viruses. While insecticides is the mainstay for mosquito control, their widespread and excessive use has led to the increased resistance in Ae. albopictus globally. Gut symbiotic bacteria are believed to play a potential role in insect physiology, potentially linking to mosquitoes\' metabolic resistance against insecticides.
METHODS: We investigated the role of symbiotic bacteria in the development of resistance in Ae. albopictus by comparing gut symbiotic bacteria between deltamethrin-sensitive and
deltamethrin-resistant populations. Adults were reared from field-collected larvae. Sensitive and resistant mosquitoes were screened using 0.03% and 0.09%
deltamethrin, respectively, on the basis of the World Health Organization (WHO) tube bioassay. Sensitive and resistant field-collected larvae were screened using 5 × LC50 (lethal concentration at 50% mortality) and 20 × LC50 concentration of
deltamethrin, respectively. Laboratory strain
deltamethrin-sensitive adults and larvae were used as controls. The DNA of gut samples from these mosquitoes were extracted using the magnetic bead method. Bacterial 16S rDNA was sequenced using BGISEQ method. We isolated and cultured gut microorganisms from adult and larvae mosquitoes using four different media: Luria Bertani (LB), brain heart infusion (BHI), nutrient agar (NA), and salmonella shigella (SS).
RESULTS: Sequencing revealed significantly higher gut microbial diversity in field-resistant larvae compared with field-sensitive and laboratory-sensitive larvae (P < 0.01). Conversely, gut microorganism diversity in field-resistant and field-sensitive adults was significantly lower compared with laboratory-sensitive adults (P < 0.01). At the species level, 25 and 12 bacterial species were isolated from the gut of field resistant larvae and adults, respectively. The abundance of Flavobacterium spp., Gemmobacter spp., and Dysgonomonas spp. was significantly higher in the gut of field-resistant larvae compared with sensitive larvae (all P < 0.05). Furthermore, the abundance of Flavobacterium spp., Pantoea spp., and Aeromonas spp. was significantly higher in the gut of field-resistant adults compared with sensitive adults (all P < 0.05). The dominant and differentially occurring microorganisms were also different between resistant larval and adult mosquitoes. These findings suggest that the gut commensal bacteria of Ae. albopictus adults and larvae may play distinct roles in their
deltamethrin resistance.
CONCLUSIONS: This study provides an empirical basis for further exploration of the mechanisms underlying the role of gut microbial in insecticide resistance, potentially opening a new prospect for mosquito control strategies.