Related Experiment Video
Updated: Nov 30, 2025
09:44
Characterization of a Pathogenic Escherichia coli Strain Derived from Oreochromis spp. Farms Using Whole-Genome Sequencing
Published on: December 23, 2022
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New Insights Into DAEC and EAEC Pathogenesis and Phylogeny.
Mario Meza-Segura1, Mussaret B Zaidi2,3, Arturo Vera-Ponce de León4
1Molecular Biomedicine Department, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico.
Frontiers in Cellular and Infection Microbiology
|November 12, 2020
Summary
This study reveals a close phylogenetic relationship between enteroaggregative (EAEC) and diffusely-adherent (DAEC) diarrheagenic E. coli. Key virulence factors were identified, suggesting potential intervention strategies for these understudied pathogens.
Area of Science:
- Microbiology
- Genomics
- Infectious Diseases
Background:
- Diarrheagenic Escherichia coli (E. coli) comprises six pathotypes, with enteroaggregative (EAEC) and diffusely-adherent (DAEC) being less understood.
- Limited genomic data exists for EAEC and DAEC strains, hindering a comprehensive understanding of their pathogenicity.
Purpose of the Study:
- To perform whole genome sequencing of EAEC and DAEC strains to elucidate their phylogenetic relationships and identify virulence factors.
- To compare genomic data with existing E. coli genomes to understand the evolutionary context of these pathotypes.
Main Methods:
- Whole genome sequencing of 10 DAEC, 9 EAEC strains from Mexican children, and 2 additional strains.
- Comparative genomic analysis of sequenced strains against 85 public E. coli genomes.
Main Results:
- EAEC and DAEC strains clustered into distinct clades, with six clades predominantly containing these pathotypes, suggesting a close phylogenetic link.
- EAEC strains possess AggR-regulated virulence factors, toxins, and bacteriocins. DAEC strains exhibit iron-scavenging systems, toxins, adhesins, and immune evasion factors.
- Specific virulence factors in both EAEC and DAEC were correlated with clinical symptoms, indicating their role in disease and potential therapeutic targets.
Conclusions:
- Genomic insights reveal a phylogenetic relationship between EAEC and DAEC, contributing to understanding their distinct pathogenic mechanisms.
- Identification of virulence factors associated with clinical presentations offers potential avenues for targeted interventions against diarrheagenic E. coli.
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