Darby Alistair C, Cho Nam-Huyk, Fuxelius Hans-Henrik, Westberg Joakim, Andersson Siv G E
Department of Molecular Evolution, Evolutionary Biology Center, Uppsala University, Norbyvägen 18C, S-752 36 Uppsala, Sweden.
Trends Genet. 2007 Oct;23(10):511-20. doi: 10.1016/j.tig.2007.08.002. Epub 2007 Sep 5.
The Rickettsiales, a genetically diverse group of the alpha-Proteobacteria, include major mammalian pathogens, such as the agents of epidemic typhus, scrub typhus, ehrlichioses and heartwater disease. Sequenced genomes of this bacterial order have provided exciting insights into reductive genome evolution, antigenic variation and host cell manipulation. Recent results suggest that human pathogens emerged relatively late in the evolution of the Rickettsiales. Surprisingly, there is no association between pathogenicity and the acquisition of novel virulence genes. Here, we explore the genomic differences between members of the Rickettsiales and ask what are the changes that enable infectious agents to emerge from seemingly harmless bacteria.
立克次氏体目属于α-变形菌纲，是一组基因多样的细菌，其中包括主要的哺乳动物病原体，如流行性斑疹伤寒、恙虫病、埃立克体病和心水病的病原体。该细菌目的测序基因组为还原性基因组进化、抗原变异和宿主细胞操纵提供了令人兴奋的见解。最近的研究结果表明，人类病原体在立克次氏体目的进化过程中出现得相对较晚。令人惊讶的是，致病性与获得新的毒力基因之间没有关联。在这里，我们探讨立克次氏体目成员之间的基因组差异，并询问是什么变化使得感染因子能够从看似无害的细菌中产生。
