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09:44
Characterization of a Pathogenic Escherichia coli Strain Derived from Oreochromis spp. Farms Using Whole-Genome Sequencing
Published on: December 23, 2022
Escherichia coli encoding Shiga toxin 2f as an emerging human pathogen.
Rita Prager1, Angelika Fruth, Ute Siewert
1Robert Koch-Institute, Burgstr. 37, D-38855 Wernigerode, Germany. pragerr@rki.de
International Journal of Medical Microbiology : IJMM
|January 23, 2009
Summary
The Shiga toxin-producing gene stx2f, previously found in pigeons, is now identified in human diarrhoeagenic Escherichia coli (E. coli) strains. This discovery highlights the emerging clinical significance of stx2f-positive E. coli and suggests its inclusion in diagnostic testing for enteric infections.
Area of Science:
- Microbiology
- Genetics
- Infectious Diseases
Background:
- The Shiga toxin-producing gene stx2f has been previously identified in Escherichia coli (E. coli) strains found in pigeons.
- Atypical enteropathogenic E. coli (aEPEC) are a category of diarrhoeagenic E. coli with varying virulence factors.
Purpose of the Study:
- To investigate the presence and characteristics of stx2f-positive E. coli in human diarrhoeagenic isolates.
- To assess the genetic diversity and potential clinical significance of these strains.
Main Methods:
- Detection of the stx2f gene in human E. coli isolates.
- Serotyping of identified strains.
- Molecular typing using Multi-Locus Sequence Typing (MLST) and Pulsed-Field Gel Electrophoresis (PFGE).
- Analysis of virulence patterns.
Main Results:
- Thirty-two stx2f-positive E. coli strains were identified, belonging to serotypes O63:H6, O128:H2, O132:H34, O145:H34, and O178:H7.
- These strains were classified as atypical enteropathogenic E. coli (aEPEC).
- The strains exhibited significant genetic diversity, falling into numerous clonal groups based on MLST, PFGE, and virulence profiles.
Conclusions:
- The presence of the stx2f allele in diverse human diarrhoeagenic E. coli strains, originally classified as aEPEC, indicates emerging clinical significance.
- It is recommended to include stx2f in the diagnostic scope for laboratory investigations of enteric infections to ensure comprehensive detection.
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