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Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
14:04

Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria

Published on: May 8, 2013

METHICILLIN-INDUCED LYSOZYME-SENSITIVE FORMS OF STAPHYLOCOCCI

K M ALDRICH, C P SWORD

    Journal of Bacteriology
    |March 1, 1964
    PubMed

    Insights

    Methicillin treatment transforms Staphylococcus bacteria into enlarged spheres. These methicillin-induced spheres become sensitive to lysozyme, causing cell lysis, unlike untreated bacteria.

    Area of Science:

    • Microbiology
    • Bacteriology
    • Cell Biology

    Background:

    • Staphylococci are common bacteria, including Staphylococcus aureus and Staphylococcus epidermidis.
    • Antibiotic resistance is a significant concern in bacterial infections.
    • Methicillin is an antibiotic used to treat bacterial infections.

    Purpose of the Study:

    • To investigate the effects of sublethal methicillin concentrations on Staphylococcus morphology.
    • To determine if methicillin-induced changes in staphylococci affect their susceptibility to lysozyme.

    Main Methods:

    • Staphylococcus aureus and S. epidermidis were cultured with sublethal doses of methicillin.
    • Cellular changes were observed using phase microscopy, Gram staining, and electron microscopy.
    • Lysozyme was added to both methicillin-treated and untreated bacterial cells.

    Main Results:

    • Staphylococci exposed to methicillin developed into enlarged spheres within 2-4 hours.
    • Methicillin-induced spheres underwent lysis upon addition of lysozyme.
    • Untreated staphylococci did not lyse when exposed to lysozyme.

    Conclusions:

    • Sublethal methicillin concentrations induce morphological changes in staphylococci, creating enlarged spheres.
    • These methicillin-induced bacterial forms exhibit increased sensitivity to lysozyme, leading to cell death.
    • This suggests a mechanism by which methicillin affects bacterial cell wall integrity and susceptibility to enzymatic degradation.
    Keywords:
    BACTERIOLYSISCARBUNCLEDNA, BACTERIALEXPERIMENTAL LAB STUDYKLEBSIELLAMETHICILLINMICROSCOPY, ELECTRONMURAMIDASEPENICILLIN RESISTANCESTAPHYLOCOCCAL INFECTIONSSTAPHYLOCOCCUS

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