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Constructing Mutants in Serotype 1 Streptococcus pneumoniae strain 519/43
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Constructing Mutants in Serotype 1 Streptococcus pneumoniae strain 519/43

Published on: September 11, 2020

Characteristics of Streptococcus pyogenes serotype M1 and M3 isolates from patients in Japan from 1981 to 1997

T Murase1, R Suzuki, R Osawa

  • 1Department of Bacteriology and Pathology, Kanagawa Prefectural Public Health Laboratory, Yokohama 241-0815, Japan. molamolatm@aol.com

Journal of Clinical Microbiology
|November 24, 1999
PubMed

Insights

Changes in Streptococcus pyogenes serotype M1/T1 strains were observed between 1981 and 1997, but not in M3/T3 strains. Further genomic analysis is needed to understand the causes of diseases like toxic shock-like syndrome (TSLS).

Area of Science:

  • Microbiology
  • Molecular Biology
  • Epidemiology

Background:

  • Streptococcus pyogenes is a significant human pathogen.
  • Understanding the evolution and characteristics of S. pyogenes isolates is crucial for public health.
  • Previous studies have indicated variability in S. pyogenes strains over time.

Purpose of the Study:

  • To characterize Streptococcus pyogenes isolates from 1981 to 1997.
  • To investigate changes in specific S. pyogenes serotypes (M1/T1 and M3/T3) over time.
  • To compare isolates from patients with toxic shock-like syndrome (TSLS) to other isolates.

Main Methods:

  • Pulsed-field gel electrophoresis (PFGE) for DNA fingerprinting.
  • Biotyping for phenotypic characterization.
  • Detection of spe genes encoding streptococcal pyrogenic exotoxins.

Main Results:

  • Serotype M1/T1 isolates from pharyngitis showed changes in PFGE profiles and spe gene presence over the study period.
  • Serotype M3/T3 isolates remained stable during the same period.
  • Isolates from TSLS patients exhibited characteristics comparable to other S. pyogenes isolates, including those from healthy subjects.

Conclusions:

  • Phenotypic and molecular characterization revealed temporal changes in M1/T1 S. pyogenes strains but not M3/T3 strains.
  • Isolates from TSLS cases were not distinct from other isolates based on the methods used.
  • Further investigation into genomic differences, such as pathogenicity islands, is necessary to elucidate the etiology of S. pyogenes-associated diseases, including TSLS.

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