Florida Medical Entomology Laboratory, IFAS, University of Florida, Vero Beach, FL, USA.
Faculty of Computer Science, Dalhousie University, Halifax, NS, B3H 1W5, Canada.
Microb Ecol. 2017 Nov;74(4):979-989. doi: 10.1007/s00248-017-0988-9. Epub 2017 May 11.
Microbiota associated with mosquito vector populations impact several traits of mosquitoes, including survival, reproduction, control, and immunity against pathogens. The influence of seasonal variations and mosquito species on mosquito gut microbiota is poorly understood. We sought to determine whether the mosquito microbiota associated with immature stages of two congeners (Culex coronator and Culex nigripalpus) differ temporally and between the two species. Using high throughput 16S rRNA gene sequence analysis, we characterized bacterial and archaeal communities found in the immature stages of the two Culex mosquito species sampled over three seasons to compare the diversity of bacteria between the two species. Beta diversity analyses of the larval microbiota sequences revealed that the two Culex species differed significantly, both temporally within each species and between the two species. Bacteria in Cx. coronator larvae were dominated by Alphaproteobacteria, mainly associated with Roseoccocus and unidentified species of Rhizobiales, and two unidentified species of Cyanobacteria. In contrast, Cx. nigripalpus was dominated by Thorsellia anophelis (Gammaproteobacteria), Clostridium, an unidentified species of Ruminococcacae (Clostridiales), and additional unidentified species associated with Erysipelotrichaceae (Erysipelotrichales), Bacteroidales, and Mollicutes. Results of our study revealed both seasonal and interspecies differences in bacterial community composition associated with the immature stages of Cx. coronator and Cx. nigripalpus vector populations in Florida. These results have important implications for our understanding of the underlying factors of variations in disease transmission among seasons, susceptibility to various pesticides, and other biotic factors, including the role of the microbiota on the spread of invasive species. In addition, our results suggest close associations of certain bacteria species with each of the two Culex species that will be further targeted for their potential in the development of microbial-based control strategies.
与蚊子种群相关的微生物群会影响蚊子的几种特征，包括生存、繁殖、控制以及对病原体的免疫力。季节变化和蚊子种类对蚊子肠道微生物群的影响还不太清楚。我们试图确定与两种近缘种（Culex coronator 和 Culex nigripalpus）的幼虫阶段相关的蚊子微生物群是否在时间上和两种物种之间存在差异。使用高通量 16S rRNA 基因序列分析，我们对三个季节采集的两种库蚊幼虫阶段的细菌和古菌群落进行了特征描述，以比较两种物种之间细菌的多样性。幼虫微生物组序列的β多样性分析表明，这两种库蚊在时间上存在显著差异，无论是在每种物种内部还是在两种物种之间。Cx. coronator 幼虫中的细菌主要由α变形菌组成，主要与 Roseoccocus 和未鉴定的 Rhizobiales 种以及两种未鉴定的蓝细菌有关。相比之下，Cx. nigripalpus 以 Thorsellia anophelis（γ变形菌）为主，其次是梭菌、未鉴定的 Ruminococcacae（Clostridiales）种以及与 Erysipelotrichaceae（Erysipelotrichales）、Bacteroidales 和 Mollicutes 相关的其他未鉴定种。我们的研究结果表明，佛罗里达州 Cx. coronator 和 Cx. nigripalpus 蚊种群的幼虫阶段的细菌群落组成存在季节性和种间差异。这些结果对我们理解季节间疾病传播变化、对各种杀虫剂的敏感性以及包括微生物群在入侵物种传播中的作用在内的其他生物因素的潜在影响具有重要意义。此外，我们的研究结果表明，某些细菌与两种库蚊的密切相关，这将进一步成为基于微生物的控制策略的潜在目标。
