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Internalization-associated proteins among Streptococcus pyogenes isolated from asymptomatic carriers and children

R Musumeci1, C Lo Bue, I Milazzo

  • 1Department of Microbiological and Gynecological Sciences, Section of Microbiology, University of Catania, 95124 Catania, Italy.

Clinical Infectious Diseases : an Official Publication of the Infectious Diseases Society of America
|July 12, 2003
PubMed

Insights

The fibronectin-binding protein gene pfbpI is more common in Streptococcus pyogenes from asymptomatic carriers. This suggests pfbpI may help S. pyogenes persist in the throat.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Epidemiology

Background:

  • Streptococcus pyogenes (S. pyogenes) is a significant human pathogen.
  • Fibronectin-binding proteins (FnBPs) are crucial for S. pyogenes colonization and virulence.
  • Understanding the role of specific FnBPs in asymptomatic carriage is important for infection control.

Purpose of the Study:

  • To investigate the prevalence of two fibronectin-binding proteins, F/SfbI and PrtF2/PfbpI, in S. pyogenes strains.
  • To determine the association between these proteins and macrolide resistance genes.
  • To analyze the role of these proteins in S. pyogenes colonization of asymptomatic carriers versus symptomatic pharyngitis patients.

Main Methods:

  • Isolation and characterization of 62 S. pyogenes strains from school children.
  • Genotyping of strains for the presence of pfbpI and prtF1 genes.
  • Analysis of the association between fibronectin-binding protein genes and macrolide resistance.

Main Results:

  • The pfbpI gene was found in a significantly higher proportion of S. pyogenes strains from asymptomatic carriers (80%) compared to children with pharyngitis (53%).
  • No significant difference in the prevalence of the prtF1 gene was observed between the two groups.
  • A significant association was found between macrolide resistance and the F/SfbI protein in both groups.

Conclusions:

  • The pfbpI gene may play a role in the persistence of S. pyogenes in the throat of asymptomatic carriers.
  • Fibronectin-binding protein F/SfbI is significantly associated with macrolide resistance in S. pyogenes.
  • These findings contribute to understanding S. pyogenes epidemiology and potential therapeutic targets.

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