期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2017
卷号：114
期号：27
页码：E5362-E5369
DOI：10.1073/pnas.1702983114
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Mosquitoes host communities of microbes in their digestive tract that consist primarily of bacteria. We previously reported that several mosquito species, including Aedes aegypti , do not develop beyond the first instar when fed a nutritionally complete diet in the absence of a gut microbiota. In contrast, several species of bacteria, including Escherichia coli , rescue development of axenic larvae into adults. The molecular mechanisms underlying bacteria-dependent growth are unknown. Here, we designed a genetic screen around E. coli that identified high-affinity cytochrome bd oxidase as an essential bacterial gene product for mosquito growth. Bioassays showed that bacteria in nonsterile larvae and gnotobiotic larvae inoculated with wild-type E. coli reduced midgut oxygen levels below 5%, whereas larvae inoculated with E. coli mutants defective for cytochrome bd oxidase did not. Experiments further supported that hypoxia leads to growth and ecdysone-induced molting. Altogether, our results identify aerobic respiration by bacteria as a previously unknown but essential process for mosquito development.
