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Updated: Jul 17, 2026
09:44
Characterization of a Pathogenic Escherichia coli Strain Derived from Oreochromis spp. Farms Using Whole-Genome Sequencing
Published on: December 23, 2022
Autotransporter-encoding sequences are phylogenetically distributed among Escherichia coli clinical isolates and
Concetta Restieri1, Geneviève Garriss, Marie-Claude Locas
1INRS-Institut Armand-Frappier, 531 Boul. des Prairies, Laval, Québec, Canada H7V 1B7.
Applied and Environmental Microbiology
|January 16, 2007
Summary
This study reveals specific autotransporter gene profiles in Escherichia coli (E. coli) strains, linking them to infection sources and phylogenetic groups, aiding in strain analysis.
Area of Science:
- Microbiology
- Genetics
- Bacterial Pathogenesis
Background:
- Autotransporters are bacterial proteins with diverse virulence functions.
- Escherichia coli (E. coli) strains cause various infections, but autotransporter distribution is poorly understood.
- Investigating autotransporter sequences aids in understanding E. coli pathogenicity.
Purpose of the Study:
- To determine the distribution of 13 autotransporter sequences and five Antigen 43 (Ag43) allelic variants in 491 E. coli isolates.
- To correlate autotransporter presence with E. coli source (clinical, diarrheagenic, avian pathogenic, reference strains) and phylogenetic groups.
- To validate a multiplex PCR assay for autotransporter screening.
Main Methods:
- Utilized a validated multiplex PCR assay to screen 491 E. coli isolates.
- Included isolates from human urinary tract infections, diarrheagenic E. coli, avian pathogenic E. coli (APEC), and ECOR reference strains.
- Classified clinical isolates into established phylogenetic groups.
Main Results:
- Ag43 alleles were more prevalent in clinical (93%) versus commensal (56%) isolates, with agn43K12 being the most common.
- Specific autotransporter genes (espC, espP, sepA, Ag43 alleles EDL933, RS218) were linked to diarrheagenic E. coli.
- Tsh associated with APEC, while sat was absent; vat, sat, and pic linked to urinary tract isolates and specific phylogenetic groups (B2, D).
Conclusions:
- Autotransporter gene profiles are associated with the source and phylogenetic background of E. coli strains.
- Autotransporter gene profiling can be a valuable tool for comparative analysis of E. coli from diverse sources.
- This research enhances understanding of E. coli virulence and evolution.
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