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[Biological properties of opportunistic microorganisms isolated from patients with acute intestinal diseases]

N A Polikarpov

    Zhurnal Mikrobiologii, Epidemiologii I Immunobiologii
    |August 1, 1987
    PubMed

    Insights

    Pathogenicity markers like DNAase and RNAase are more common in intestinal pathogens and opportunistic bacteria from sick individuals compared to those from healthy people.

    Area of Science:

    • Microbiology
    • Infectious Diseases

    Background:

    • Intestinal infections are often caused by Shigella and Salmonella species.
    • Opportunistic bacteria can also play a role in acute intestinal diseases.
    • Pathogenicity markers are key indicators of bacterial virulence.

    Purpose of the Study:

    • To compare the incidence of pathogenicity markers (DNAase, RNAase, phosphatase, hemolytic activity) in Shigella, Salmonella, and opportunistic bacteria.
    • To differentiate between opportunistic bacteria from patients with acute intestinal diseases and healthy individuals based on these markers.

    Main Methods:

    • Comparative analysis of pathogenicity marker incidence.
    • Isolation and identification of bacteria from fecal samples.
    • Assays for DNAase, RNAase, phosphatase, and hemolytic activity.

    Main Results:

    • DNAase and RNAase activity were most frequent in Shigella flexneri and Salmonella.
    • Opportunistic enterobacteria from patients with acute intestinal diseases showed higher DNAase and RNAase activity.
    • A significant difference in DNAase and RNAase activity was observed between opportunistic bacteria from patients and healthy individuals.

    Conclusions:

    • DNAase and RNAase activity are significant markers differentiating pathogenic and opportunistic bacteria in intestinal infections.
    • These markers can help distinguish between bacteria associated with disease and those found in healthy carriers.

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