University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
Clin Microbiol Infect. 2015 May;21(5):468.e7-18. doi: 10.1016/j.cmi.2014.12.009. Epub 2014 Dec 27.
Shiga toxin-producing Escherichia coli (STEC) O104:H4 emerged as an important pathogen when it caused a large outbreak in Germany in 2011. Little is known about the evolutionary history and genomic diversity of the bacterium. The current communication describes a comprehensive analysis of STEC O104:H4 genomes from the 2011 outbreak and other non-outbreak-related isolates. Outbreak-related isolates formed a tight cluster that shared a monophyletic relation with two non-outbreak clusters, suggesting that all three clusters originated from a common ancestor. Eight single nucleotide polymorphisms, seven of which were non-synonymous, distinguished outbreak from non-outbreak isolates. Lineage-specific markers indicated that recent partitions were driven by selective pressures associated with niche adaptation. Based on the results, an evolutionary model for STEC O104:H4 is proposed. Our analysis provides the evolutionary context at population level and describes the emergence of clones with novel properties, which is necessary for developing comprehensive approaches to early warning and control.
产志贺毒素大肠杆菌（STEC）O104：H4 在 2011 年德国大规模暴发时成为一种重要的病原体。人们对该细菌的进化历史和基因组多样性知之甚少。本研究描述了对 2011 年暴发相关的 STEC O104：H4 基因组以及其他非暴发相关分离株的全面分析。暴发相关的分离株形成了一个紧密的聚类，与两个非暴发聚类具有单系关系，提示所有三个聚类都起源于一个共同的祖先。8 个单核苷酸多态性，其中 7 个是非同义的，将暴发相关的分离株与非暴发相关的分离株区分开来。谱系特异性标记表明，最近的分支是由与生态位适应相关的选择压力驱动的。基于这些结果，提出了 STEC O104：H4 的进化模型。我们的分析提供了群体水平的进化背景，并描述了具有新特性的克隆的出现，这对于制定全面的早期预警和控制方法是必要的。
