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Genome-wide Gene Deletions in Streptococcus sanguinis by High Throughput PCR
14:07

Genome-wide Gene Deletions in Streptococcus sanguinis by High Throughput PCR

Published on: November 23, 2012

Nonhemolytic Streptococcus pyogenes isolates that lack large regions of the sag operon mediating streptolysin S

Miho Yoshino1, Somay Y Murayama, Katsuhiko Sunaoshi

  • 1Laboratory of Molecular Epidemiology for Infectious Agents, Kitasato Institute for Life Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan.

Journal of Clinical Microbiology
|December 19, 2009
PubMed

Insights

Three deletions were found in nonhemolytic Streptococcus pyogenes strains from patients with pharyngitis or acute otitis media. These genetic changes impact extracellular matrix binding protein and streptolysin S production.

Area of Science:

  • Microbiology
  • Genetics
  • Infectious Diseases

Background:

  • Streptococcus pyogenes, also known as group A Streptococcus, is a significant human pathogen.
  • Nonhemolytic strains of S. pyogenes can cause infections like pharyngitis and acute otitis media.
  • Understanding the genetic basis of S. pyogenes virulence factors is crucial for disease control.

Purpose of the Study:

  • To investigate genetic variations in nonhemolytic Streptococcus pyogenes strains.
  • To identify specific genetic deletions and their potential impact on virulence factors.

Main Methods:

  • Isolation of Streptococcus pyogenes strains from patients with pharyngitis or acute otitis media.
  • Genomic analysis to identify deletions in specific gene regions.

Main Results:

  • Nine nonhemolytic Streptococcus pyogenes strains were analyzed.
  • Three distinct deletions were identified in the region spanning the epf gene to the sag operon.
  • The epf gene encodes an extracellular matrix binding protein, and the sag operon mediates streptolysin S production.

Conclusions:

  • Genetic deletions affecting key virulence factor genes are present in some nonhemolytic S. pyogenes strains.
  • These deletions may influence the pathogenicity of S. pyogenes in causing pharyngitis and acute otitis media.

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