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Characterization of a Pathogenic Escherichia coli Strain Derived from Oreochromis spp. Farms Using Whole-Genome Sequencing
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High-molecular-weight plasmid correlates with Escherichia coli enteroinvasiveness

J R Harris, I K Wachsmuth, B R Davis

    Infection and Immunity
    |September 1, 1982
    PubMed

    Insights

    A large plasmid in Escherichia coli strains is linked to enteroinvasiveness. This finding aids in understanding bacterial virulence factors and disease potential in E. coli.

    Area of Science:

    • Microbiology
    • Molecular Biology
    • Genetics

    Background:

    • Escherichia coli (E. coli) can cause various infections.
    • Enteroinvasiveness is a key virulence factor in pathogenic E. coli strains.
    • Plasmids are extrachromosomal DNA elements that can carry virulence genes.

    Purpose of the Study:

    • To investigate the association between plasmid presence and enteroinvasiveness in E. coli.
    • To identify specific plasmids linked to the Sereny test-positive phenotype.

    Main Methods:

    • Sereny assay was performed on 31 E. coli strains.
    • Plasmid DNA was extracted and analyzed from the tested strains.
    • Statistical analysis was used to correlate plasmid presence with invasiveness.

    Main Results:

    • A 140-megadalton plasmid was detected in E. coli strains.
    • The presence of this 140-MDa plasmid showed a significant association with positive Sereny test results.
    • This suggests a role for the plasmid in E. coli invasiveness.

    Conclusions:

    • The 140-megadalton plasmid is a potential virulence factor in E. coli.
    • Further research can explore the genes on this plasmid to understand enteroinvasiveness mechanisms.
    • This discovery contributes to the characterization of pathogenic E. coli.

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