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[The phage sensitivity and lysogeny of cultures of Streptococcus pyogenes group A isolated in different streptococcal

T K Asoskova, A V Aksenova, I M Liampert

    Zhurnal Mikrobiologii, Epidemiologii I Immunobiologii
    |September 1, 1996
    PubMed

    Insights

    Streptococcus pyogenes (S. pyogenes) strains show varied phage sensitivity linked to diseases like rheumatism and glomerulonephritis. Lysogeny, the integration of phage DNA, is common in S. pyogenes, particularly in tonsillitis patients.

    Area of Science:

    • Microbiology
    • Bacteriology
    • Virology

    Background:

    • A collection of moderate phages targeting Streptococcus pyogenes (group A) was previously established.
    • Streptococcus pyogenes is an important human pathogen associated with various infections.

    Purpose of the Study:

    • To investigate the differential sensitivity of S. pyogenes strains from patients with rheumatism, glomerulonephritis, and tonsillitis to a specific phage collection.
    • To determine the prevalence and characteristics of lysogeny in S. pyogenes strains isolated from these patient groups.

    Main Methods:

    • Bacteriophage typing of S. pyogenes isolates using a defined collection of moderate phages.
    • Assessment of phage sensitivity and resistance patterns.
    • Detection and characterization of lysogeny in S. pyogenes strains.

    Main Results:

    • S. pyogenes strains exhibited distinct phage lysis patterns: rheumatism isolates were lysed by groups II and III phages, tonsillitis isolates by group III, and glomerulonephritis isolates by group I.
    • Lysogeny was prevalent across S. pyogenes strains from all studied diseases.
    • Lysogeny was most frequent in tonsillitis isolates, with only phage-resistant strains being lysogenic.
    • In rheumatism and glomerulonephritis, lysogeny was observed in both phage-sensitive and phage-resistant S. pyogenes strains.

    Conclusions:

    • Phage sensitivity profiles of S. pyogenes correlate with specific clinical conditions.
    • Lysogeny is a widespread phenomenon in S. pyogenes, with variations in its association with phage sensitivity depending on the disease context.

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