A ubiquitous mobile genetic element changes the antagonistic weaponry of a human gut symbiont

• 成果类型: Article
• 署名作者: Sheahan, Madeline L.; Flores, Katia; Coyne, Michael J.; Garcia-Bayona, Leonor; Chatzidaki-Livanis, Maria; Holst, Andrea Q.; Smith, Rita C.; Sundararajan, Anitha; Barquera, Blanca; Comstock, Laurie E.
• 署名单位: University of Chicago; University of Chicago; Harvard University; Harvard Medical School; Harvard University Medical Affiliates; Brigham & Women's Hospital; Technical University of Denmark; Rensselaer Polytechnic Institute; Rensselaer Polytechnic Institute; Rensselaer Polytechnic Institute; Stanford University; University System of Ohio; Ohio University; Chr Hansen
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-9362
• DOI: 10.1126/science.adj9504
• 发表日期: 2024-10-25
• 页码: 414-420
• 关键词: bacteroides-fragilis; expression; immunity

摘要

DNA transfer is ubiquitous in the human gut microbiota, especially among species of the order Bacteroidales. In silico analyses have revealed hundreds of mobile genetic elements shared between these species, yet little is known about the phenotypes they encode, their effects on fitness, or pleiotropic consequences for the recipient's genome. In this work, we show that acquisition of a ubiquitous integrative conjugative element (ICE) encoding a type VI secretion system (T6SS) shuts down the native T6SS of Bacteroides fragilis. Despite inactivating this T6SS, ICE acquisition increases the fitness of the B. fragilis transconjugant over its progenitor by arming it with the new T6SS. DNA transfer causes the strain to change allegiances so that it no longer targets ecosystem members with the same element yet is armed for communal defense.