Comparison of whole genome sequences from human and non-human Escherichia coli O26 strains
Comparison of whole genome sequences from human and non-human Escherichia coli O26 strains
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人类和非人类大肠杆菌 O26 菌株的全基因组序列比较
DOI：
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发表时间：
2015
影响因子：
5.7
通讯作者：
J. Bono
中科院分区：
文献类型：
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作者：
K. N. Norman;M. Clawson;N. Strockbine;R. Mandrell;Roger P. Johnson;K. Ziebell;Shaohua Zhao;P. Fratamico;R. Stones;M. Allard;J. Bono
产滋贺毒素大肠杆菌（STEC）O 26是第二大大肠杆菌。大肠杆菌血清群是继大肠杆菌之后导致人类疾病爆发的主要原因。coli O157：H7。最近的疫情与新出现的仅携带stx 2的致病性O26：H11菌株有关。牛被认为是携带stx 1的O26菌株的重要宿主;然而，这些新出现的stx 2菌株的宿主尚不清楚。本研究的目的是确定人和牛源菌株的核苷酸多态性，以比较两种宿主物种之间的多态性衍生的基因型和毒力基因谱的差异。对182株流行病学无关的O26菌株进行全基因组测序，其中包括109株人源菌株和73株非人源菌株。随后使用通过全基因组测序鉴定的一组283个多态性对一组289个O26菌株（241个STEC和48个非STEC）进行基因分型，得到64个独特的基因型。系统发育分析确定了O26菌株内的7个簇。这7个聚类没有区分来自人类或牛的分离株;然而，聚类确实与特定的毒力基因谱相对应。携带stx 1的人类和非人类来源的菌株与携带stx 2的菌株、携带eae的菌株和非STEC菌株分开聚类。携带stx 2的菌株与非STEC菌株和携带eae的菌株的关系比携带stx 1的菌株更密切。人源和牛源菌株具有相同的多态性衍生基因型和相似的毒力基因谱，这一发现提供了证据，证明在牛和人中发现了相似的菌株，并且可能发生两个物种之间的传播。
Shiga toxin-producing Escherichia coli (STEC) O26 is the second leading E. coli serogroup responsible for human illness outbreaks behind E. coli O157:H7. Recent outbreaks have been linked to emerging pathogenic O26:H11 strains harboring stx2 only. Cattle have been recognized as an important reservoir of O26 strains harboring stx1; however the reservoir of these emerging stx2 strains is unknown. The objective of this study was to identify nucleotide polymorphisms in human and cattle-derived strains in order to compare differences in polymorphism derived genotypes and virulence gene profiles between the two host species. Whole genome sequencing was performed on 182 epidemiologically unrelated O26 strains, including 109 human-derived strains and 73 non-human-derived strains. A panel of 289 O26 strains (241 STEC and 48 non-STEC) was subsequently genotyped using a set of 283 polymorphisms identified by whole genome sequencing, resulting in 64 unique genotypes. Phylogenetic analyses identified seven clusters within the O26 strains. The seven clusters did not distinguish between isolates originating from humans or cattle; however, clusters did correspond with particular virulence gene profiles. Human and non-human-derived strains harboring stx1 clustered separately from strains harboring stx2, strains harboring eae, and non-STEC strains. Strains harboring stx2 were more closely related to non-STEC strains and strains harboring eae than to strains harboring stx1. The finding of human and cattle-derived strains with the same polymorphism derived genotypes and similar virulence gene profiles, provides evidence that similar strains are found in cattle and humans and transmission between the two species may occur.