Scholarlink

Background <p>Among intestinal pathogenic <i>Escherichia coli</i>, hybrid pathotypes carrying virulence determinants of multiple classical pathotypes have recently been identified.</p> Methods <p>A total of 292 <i>E. coli</i> isolates were collected from human, livestock, and environmental sources in South Korea, and their whole genome sequences were determined. They were classified into pathotypes based on virulence gene profiles. We constructed a phylogenetic tree based on cgSNPs. Synteny analysis on the LEE pathogenicity island was performed, and enriched accessory gene repertoires in particular hybrid-pathotypes were identified. Bacterial virulence was measured by lactate dehydrogenase (LDH) cytotoxicity assays. Genetic factors associated with increased cytotoxicity in the LDH assay were identified using SPLASH.</p> Results <p>Among 192 intestinal pathogenic <i>E. coli</i> isolates, 63 hybrid pathotype isolates (38 STEC/EPEC, 23 STEC/ETEC, and 2 STEC/EAEC) were identified. Two main groups of STEC/EPEC hybrid-pathotype isolates and one major STEC/ETEC group were identified. Both groups of STEC/EPEC hybrid isolates were closely associated with EPEC mono-pathotype isolates, and most STEC/ETEC hybrid groups clustered with STEC mono-pathotype isolates. Synteny analysis on the LEE pathogenicity island also showed that some STEC/EPEC hybrids might originate from EPEC genomic backbone. Based on the LDH assay, cytotoxicity was higher in STEC/ETEC, but lower in STEC/EPEC. Five gene modules (adhesion-pili, plasmid conjugation, flagella-motility, iron uptake, and T3SS) were identified to be genetic factors correlated with increased cytotoxicity in STEC/ETEC.</p> Conclusion <p>High prevalence of hybrid-pathotype <i>E coli</i> isolates was identified. They might emerge repeatedly by independent incorporation of additional virulence factors, and genomic backbones and cytotoxicity differed according to the specific hybrid pathotype.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Comparison of hybrid-and mono-pathotype Escherichia coli isolates from South Korea based on whole genome analysis and cytotoxicity assay

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年4月13日

查看全文
  • Jong Hyun Shin,
  • Min Seok Kim,
  • Ji Young Choi,
  • Sunju Kim,
  • Kun Taek Park,
  • Mi-Ran Seo,
  • Seung-Hyun Jung,
  • Yeun-Jun Chung,
  • Hyeri Seok,
  • Hae Suk Cheong,
  • Ki-Tae Kwon,
  • Bo Kyeung Jung,
  • Cheol-In Kang,
  • Doo-Ryeon Chung,
  • Dongwoo Shin,
  • Kwan Soo Ko

摘要

Background

Among intestinal pathogenic Escherichia coli, hybrid pathotypes carrying virulence determinants of multiple classical pathotypes have recently been identified.

Methods

A total of 292 E. coli isolates were collected from human, livestock, and environmental sources in South Korea, and their whole genome sequences were determined. They were classified into pathotypes based on virulence gene profiles. We constructed a phylogenetic tree based on cgSNPs. Synteny analysis on the LEE pathogenicity island was performed, and enriched accessory gene repertoires in particular hybrid-pathotypes were identified. Bacterial virulence was measured by lactate dehydrogenase (LDH) cytotoxicity assays. Genetic factors associated with increased cytotoxicity in the LDH assay were identified using SPLASH.

Results

Among 192 intestinal pathogenic E. coli isolates, 63 hybrid pathotype isolates (38 STEC/EPEC, 23 STEC/ETEC, and 2 STEC/EAEC) were identified. Two main groups of STEC/EPEC hybrid-pathotype isolates and one major STEC/ETEC group were identified. Both groups of STEC/EPEC hybrid isolates were closely associated with EPEC mono-pathotype isolates, and most STEC/ETEC hybrid groups clustered with STEC mono-pathotype isolates. Synteny analysis on the LEE pathogenicity island also showed that some STEC/EPEC hybrids might originate from EPEC genomic backbone. Based on the LDH assay, cytotoxicity was higher in STEC/ETEC, but lower in STEC/EPEC. Five gene modules (adhesion-pili, plasmid conjugation, flagella-motility, iron uptake, and T3SS) were identified to be genetic factors correlated with increased cytotoxicity in STEC/ETEC.

Conclusion

High prevalence of hybrid-pathotype E coli isolates was identified. They might emerge repeatedly by independent incorporation of additional virulence factors, and genomic backbones and cytotoxicity differed according to the specific hybrid pathotype.