Comparison of Extraintestinal Pathogenic Escherichia coli Strains from Human and Avian Sources Reveals a Mixed Subset Representing Potential Zoonotic Pathogens
Comparison of Extraintestinal Pathogenic Escherichia coli Strains from Human and Avian Sources Reveals a Mixed Subset Representing Potential Zoonotic Pathogens
复制标题
DOI：
10.1128/aem.01395-08
复制
发表时间：
2008-11-01
影响因子：
4.4
通讯作者：
Nolan, Lisa K.
中科院分区：
文献类型：
--
作者：
Johnson, Timothy J.;Wannemuehler, Yvonne;Nolan, Lisa K.
由于来自人类和禽类宿主的肠外致病性大肠杆菌(ExPEC)菌株在建立肠外感染方面遇到了相似的挑战，它们可能具有相似的毒力基因含量和致病能力。在本研究中，1,074株ExPEC分离株根据系统发育群和67个其他性状(包括毒力相关基因和质粒复制子类型)进行了分类。这些ExPEC分离株包括来自禽类大肠杆菌病的452株禽致病性大肠杆菌，91株引起新生儿脑膜炎的新生儿脑膜炎大肠杆菌(NMEC)，以及来自人尿路感染的531株尿路致病大肠杆菌。对数据的聚类分析表明，每个亚型的大多数成员代表一个遗传上不同的群体，并具有明显的特征。然而，一个包含108个ExPEC分离物的基因分型簇被鉴定出来，在亚型方面严重混合，其中有大量的性状重叠。该群内的许多分离物属于O1、O2或O18血清组。此外，58%的人属于ST95多位点序列分型组，其中90%以上的人属于典型的人类ExPEC株的B2系统发育组。该簇包含大量与染色体和质粒相关的ExPEC基因的菌株。这一具有人畜共患潜力的ExPEC亚群的进一步特征促使未来的研究探索某些ExPEC毒株在人与动物之间传播的可能性。此外，在NMEC菌株和混合簇成员中广泛存在的质粒表明，这些致病类型中的质粒介导的毒力值得进一步关注。
Since extraintestinal pathogenic Escherichia coli (ExPEC) strains from human and avian hosts encounter similar challenges in establishing infection in extraintestinal locations, they may share similar contents of virulence genes and capacities to cause disease. In the present study, 1,074 ExPEC isolates were classified by phylogenetic group and possession of 67 other traits, including virulence-associated genes and plasmid replicon types. These ExPEC isolates included 452 avian pathogenic E. coli strains from avian colibacillosis, 91 neonatal meningitis E. coli (NMEC) strains causing human neonatal meningitis, and 531 uropathogenic E. coli strains from human urinary tract infections. Cluster analysis of the data revealed that most members of each subpathotype represent a genetically distinct group and have distinguishing characteristics. However, a genotyping cluster containing 108 ExPEC isolates was identified, heavily mixed with regard to subpathotype, in which there was substantial trait overlap. Many of the isolates within this cluster belonged to the O1, O2, or O18 serogroup. Also, 58% belonged to the ST95 multilocus sequence typing group, and over 90% of them were assigned to the B2 phylogenetic group typical of human ExPEC strains. This cluster contained strains with a high number of both chromosome-and plasmid-associated ExPEC genes. Further characterization of this ExPEC subset with zoonotic potential urges future studies exploring the potential for the transmission of certain ExPEC strains between humans and animals. Also, the widespread occurrence of plasmids among NMEC strains and members of the mixed cluster suggests that plasmid-mediated virulence in these pathotypes warrants further attention.