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[Characteristic of virulence potential of clinical isolates of enterococci]

O V Bukharin, I V Valysheva, O L Kartashova

    Zhurnal Mikrobiologii, Epidemiologii I Immunobiologii
    |September 5, 2013
    PubMed
    Abstract

    Insights

    Enterococci virulence factors were analyzed in clinical isolates. Genetic virulence determinants were more common in E. faecalis, with hyaluronidase synthesis gene specific to E. faecium.

    Area of Science:

    • Microbiology
    • Molecular Biology
    • Genetics

    Context:

    • Enterococci are significant human pathogens.
    • Understanding enterococcal virulence is crucial for infection control.
    • Clinical isolates present a diverse range of virulence potential.

    Purpose:

    • To determine the virulence of enterococci strains from human clinical samples.
    • To compare phenotypical and genotypical virulence factors.
    • To investigate the distribution of specific virulence genes.

    Summary:

    • 30 enterococcal strains (E. faecalis, E. faecium) from clinical sources were analyzed.
    • Phenotypic tests (hemolysis, gelatinase, proteolysis) and genotypic PCR for virulence genes (gelE, sprE, cyl, HYL, ASA) were performed.
    • Both E. faecalis and E. faecium exhibited virulence factors, with genetic determinants more prevalent in E. faecalis.

    Impact:

    • Findings reveal that genetic virulence factors are more widespread in E. faecalis clinical isolates.
    • The study highlights the biotope-dependent gene set for virulence in E. faecalis.
    • The gene for hyaluronidase synthesis (HYL) is identified as characteristic for E. faecium.
    • A correlation between phenotypic traits and enterococcal genotype was established.

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