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Published on: August 19, 2016

Production of proteinase by hemolytic streptococci in various clinical conditions

S ROTHBARD, E W TODD

    The Journal of Experimental Medicine
    |April 1, 1948
    PubMed

    Insights

    Group A streptococci proteinase production is consistent and unaffected by sulfadiazine therapy. This proteinase activity is linked to the bacterial strain, not the serological type or clinical outcome.

    Area of Science:

    • Microbiology
    • Bacteriology
    • Streptococcal Infections

    Background:

    • Group A streptococci are significant human pathogens.
    • Streptococcal proteinase is a key virulence factor.
    • Understanding factors influencing proteinase production is crucial for disease management.

    Purpose of the Study:

    • To investigate the consistency of proteinase activity in Group A streptococci strains.
    • To determine the impact of sulfadiazine therapy on streptococcal proteinase production.
    • To explore the relationship between proteinase production, serological type, and clinical response.

    Main Methods:

    • Isolation of Group A streptococci from patients in acute and convalescent illness phases.
    • Assay of proteinase activity in isolated bacterial strains.
    • Correlation analysis between proteinase production, serological typing, and clinical data.

    Main Results:

    • Proteinase activity was remarkably constant across strains and illness phases.
    • Sulfadiazine therapy did not alter proteinase production by infecting streptococci.
    • No correlation was found between proteinase production capacity, serological type, and clinical response.

    Conclusions:

    • Streptococcal proteinase production is an inherent strain-specific characteristic.
    • Antibiotic therapy does not influence the expression of this virulence factor.
    • Proteinase production capacity does not predict clinical outcomes in streptococcal infections.
    Keywords:
    ENZYMES/proteolytic

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