Doyle Marie, Fookes Maria, Ivens Al, Mangan Michael W, Wain John, Dorman Charles J
Department of Microbiology, Moyne Institute of Preventive Medicine, Trinity College Dublin, Dublin 2, Ireland.
Science. 2007 Jan 12;315(5809):251-2. doi: 10.1126/science.1137550.
The Sfh protein is encoded by self-transmissible plasmids involved in human typhoid and is closely related to the global regulator H-NS. We have found that Sfh provides a stealth function that allows the plasmids to be transmitted to new bacterial hosts with minimal effects on their fitness. Introducing the plasmid without the sfh gene imposes a mild H-NS(-) phenotype and a severe loss of fitness due to titration of the cellular pool of H-NS by the A+T-rich plasmid. This stealth strategy seems to be used widely to aid horizontal DNA transmission and has important implications for bacterial evolution.
Sfh蛋白由参与人类伤寒的自我传递质粒编码，并且与全局调节因子H-NS密切相关。我们发现Sfh提供了一种隐蔽功能，使质粒能够传递到新的细菌宿主，而对其适应性的影响最小。引入不含sfh基因的质粒会产生轻度的H-NS（-）表型，并且由于富含A+T的质粒对细胞内H-NS池的滴定作用，导致适应性严重丧失。这种隐蔽策略似乎被广泛用于协助水平DNA传递，并且对细菌进化具有重要意义。
