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[The characteristics of the initial link in the intestinal lesion by opportunistic Proteus mirabilis bacteria]

V K Koval'chuk, L V Parkhomenko

    Mikrobiologicheskii Zhurnal
    |November 1, 1991
    PubMed

    Insights

    Proteus mirabilis exhibits general toxic action on intestinal epithelium cells, degrading the brush border membrane without causing cell destruction. A heat-stable bacterial fraction is identified as the damaging factor.

    Area of Science:

    • Microbiology
    • Cell Biology
    • Toxicology

    Background:

    • The interaction between gut microbiota and the intestinal epithelium is crucial for host health.
    • Understanding bacterial virulence factors is essential for preventing gastrointestinal infections.

    Purpose of the Study:

    • To investigate the effects of Proteus mirabilis on the intestinal epithelium of mice.
    • To identify the specific factors responsible for bacterial-induced damage.

    Main Methods:

    • Bacteriological analysis
    • Toxicological assays
    • Electron microscopy
    • In vivo mouse model

    Main Results:

    • Proteus mirabilis induced general toxic effects on enterocytes and epithelial cells.
    • Degradation of the brush border membrane was observed, but no cell lysis occurred.
    • A thermostable, large-molecular fraction in the bacterial culture fluid was identified as the damaging agent.
    • Damage was evident within hours of bacterial contact with the intestinal mucosa.
    • Compromised mucosal barriers allowed deeper penetration of Proteus mirabilis into intestinal tissues.

    Conclusions:

    • Proteus mirabilis exerts a toxic effect on the intestinal epithelium, primarily through brush border membrane degradation.
    • A specific bacterial fraction mediates this toxicity.
    • Bacterial colonization and weakened host defenses facilitate tissue invasion.

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