[Source: Cell Host & Microbe, full page: (LINK). Abstract, edited.]
A Gut Commensal Bacterium Promotes Mosquito Permissiveness to Arboviruses
Pa Wu, Peng Sun, Kaixiao Nie, Yibin Zhu, Mingyu Shi, Changguang Xiao, Han Liu, Qiyong Liu, Tongyan Zhao, Xiaoguang Chen, Hongning Zhou, Penghua Wang, Gong Cheng 9
Published: December 27, 2018 / DOI:https://doi.org/10.1016/j.chom.2018.11.004
- The gut commensal Serratia marcescens promotes mosquito permissiveness to arboviruses
- S. marcescens facilitates arboviral infection via a secreted protein named SmEnhancin
- SmEnhancin digests gut membrane-bound mucins to enhance viral dissemination in mosquitoes
- S. marcescens enhances the susceptibility of field mosquitoes to dengue virus
Mosquitoes are hematophagous vectors that can acquire human viruses in their intestinal tract. Here, we define a mosquito gut commensal bacterium that promotes permissiveness to arboviruses. Antibiotic depletion of gut bacteria impaired arboviral infection of a lab-adapted Aedes aegypti mosquito strain. Reconstitution of individual cultivable gut bacteria in antibiotic-treated mosquitoes identified Serratia marcescens as a commensal bacterium critical for efficient arboviral acquisition.S. marcescens facilitates arboviral infection through a secreted protein named SmEnhancin, which digests membrane-bound mucins on the mosquito gut epithelia, thereby enhancing viral dissemination. Field Aedes mosquitoes positive forS. marcescens were more permissive to dengue virus infection than those free of S. marcescens. Oral introduction ofS. marcescens into field mosquitoes that lack this bacterium rendered these mosquitoes highly susceptible to arboviruses. This study defines a commensal-driven mechanism that contributes to vector competence, and extends our understanding of multipartite interactions among hosts, the gut microbiome, and viruses.
Keywords: mosquito – microbiota – arbovirus – Serratia marcescens – Enhancin
Keywords: Arbovirus; Mosquitoes; Aedes spp.; Serratia marcescens.