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PerR controls peroxide- and iron-responsive expression of oxidative stress defense genes in Helicobacter hepaticus

C Belzer, B A M van Schendel, T Hoogenboezem

    European Journal of Microbiology & Immunology
    |February 12, 2014
    PubMed

    Insights

    Helicobacter hepaticus uses the PerR regulator to control genes involved in oxidative stress defense, like katA and ahpC. This regulation is crucial for the bacteria

    Area of Science:

    • Microbiology
    • Bacterial Pathogenesis
    • Oxidative Stress Response

    Background:

    • Chronic Helicobacter hepaticus colonization causes inflammatory diseases.
    • H. hepaticus encounters oxidative stress during colonization.
    • The PerR regulator's role in oxidative stress response is unknown.

    Purpose of the Study:

    • Investigate the role of H. hepaticus PerR (HH0942) in regulating oxidative stress genes.
    • Determine the impact of PerR on katA (HH0043) and ahpC (HH1564) gene expression.
    • Understand the connection between iron metabolism and oxidative stress defense in H. hepaticus.

    Main Methods:

    • Gene expression analysis (transcription and protein levels).
    • Hydrogen peroxide and iron restriction induction assays.
    • Gene inactivation studies (perR and katA mutants).

    Main Results:

    • PerR regulates katA and ahpC expression, which are induced by hydrogen peroxide and iron restriction.
    • PerR inactivation leads to constitutive, iron-independent expression of katA and ahpC.
    • katA inactivation increases H. hepaticus sensitivity to hydrogen peroxide and reduces aerotolerance.

    Conclusions:

    • The PerR regulatory protein connects iron metabolism and oxidative stress defense in H. hepaticus.
    • This regulatory mechanism is similar to Campylobacter jejuni but differs from Helicobacter pylori.
    • PerR-mediated regulation is essential for H. hepaticus survival under oxidative stress conditions.
    Keywords:
    H. hepaticuscatalasegene regulationironoxidative stress defenseperoxide

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