Escherichia coli sequence type 131 (ST131) is a major cause of urinary and bloodstream infections. Its association with extended-spectrum β-lactamases (ESBLs) significantly complicates treatment. Its best-described component is the rapidly expanding H30Rx clade, containing allele 30 of the type 1 fimbrial adhesin gene fimH. This lineage appears to have emerged in the United States and spread around the world in part due to the acquisition of the ESBL-encoding bla_CTX-M-15 gene and resistance to fluoroquinolones. However, non-H30 ST131 sublineages with other acquired CTX-M-type resistance genes are also emerging. Based on whole-genome analyses, we describe here the presence of an (fimH) H27 E. coli ST131 sublineage that has recently caused an outbreak of community-acquired bacteremia and recurrent urinary tract infections (UTIs) in Denmark. This sublineage has acquired both a virulence plasmid (pAA) that defines the enteroaggregative E. coli (EAEC) diarrheagenic pathotype and multiple genes associated with extraintestinal E. coli (ExPEC); combined, these traits have made this particular ST131 sublineage successful at colonizing its human host and causing recurrent UTI. Moreover, using a historic World Health Organization (WHO) E. coli collection and publicly available genome sequences, we identified a global H27 EAEC ST131 sublineage that dates back as far as 1998. Most H27 EAEC ST131 isolates harbor pAA or pAA-like plasmids, and our analysis strongly implies a single ancestral acquisition among these isolates. These findings illustrate both the profound plasticity of this important pathogenic E. coli ST131 H27 sublineage and genetic acquisitions of EAEC-specific virulence traits that likely confer an enhanced ability to cause intestinal colonization.

中文翻译：

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ST131 谱系中肠聚集性大肠杆菌的出现是肠外感染的一个原因。

大肠杆菌序列 131 型 (ST131) 是尿路和血流感染的主要原因。它与超广谱 β-内酰胺酶 (ESBL) 的关联使治疗显着复杂化。其描述得最好的组件是快速扩展的H 30Rx 进化枝，包含 1 型菌毛粘附素基因fimH 的等位基因 30 。这一谱系似乎出现在美国并传播到世界各地，部分原因是获得了编码 ESBL 的bla _CTX-M-15基因和对氟喹诺酮类药物的耐药性。然而，具有其他获得性 CTX-M 型抗性基因的非H 30 ST131 亚系也在出现。基于全基因组分析，我们在此描述了 ( fimH) H 27大肠杆菌ST131 亚系最近在丹麦引起社区获得性菌血症和复发性尿路感染 (UTI) 的爆发。该亚系获得了定义肠聚集性大肠杆菌(EAEC) 腹泻致病型的毒力质粒(pAA)和与肠外大肠杆菌(ExPEC)相关的多个基因；综合起来，这些特征使这个特殊的 ST131 亚系成功地定植其人类宿主并导致复发性尿路感染。此外，使用历史悠久的世界卫生组织 (WHO)大肠杆菌收集和公开可用的基因组序列，我们确定了一个全球H27 EAEC ST131 亚系可追溯到 1998 年。大多数H 27 EAEC ST131 分离株含有 pAA 或 pAA 样质粒，我们的分析强烈暗示这些分离株之间有单一的祖先获得。这些发现说明了这种重要的致病性大肠杆菌ST131 H 27 亚系的深刻可塑性和 EAEC 特异性毒力性状的遗传获得，这可能会增强导致肠道定植的能力。