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Is plasminogen deployed as a Streptococcus pyogenes virulence factor?

Mark J Walker1, Jason D McArthur, Fiona McKay

  • 1School of Biological Sciences, University of Wollongong, NSW, 2522 Australia. mwalker@uow.edu.au

Trends in Microbiology
|June 7, 2005
PubMed

Insights

Streptococcus pyogenes utilizes human plasminogen for cell surface proteolysis, aiding its spread. This study highlights plasminogen

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Molecular Biology

Background:

  • Streptococcus pyogenes (group A Streptococcus) causes significant human infections, ranging from skin and throat infections to severe invasive diseases like necrotizing fasciitis.
  • A concerning resurgence of group A streptococcal infections and invasive disease has been observed in developed nations over the last twenty years.
  • S. pyogenes employs diverse mechanisms to acquire and activate human plasminogen, resulting in potent proteolytic activity on its surface.

Purpose of the Study:

  • To investigate the role of human plasminogen in the in vivo dissemination of Streptococcus pyogenes.
  • To elucidate the mechanisms by which S. pyogenes interacts with human plasminogen for enhanced virulence.

Main Methods:

  • Utilized a humanized transgenic mouse model to study Streptococcus pyogenes dissemination.
  • Analyzed bacterial acquisition and activation pathways of human plasminogen by S. pyogenes.

Main Results:

  • Experimental evidence from the humanized mouse model indicates a critical role for human plasminogen in S. pyogenes dissemination within the host.
  • Demonstrated that S. pyogenes secures potent proteolytic activity on its cell surface through plasminogen interaction.

Conclusions:

  • Human plasminogen is essential for the in vivo spread of Streptococcus pyogenes.
  • Targeting the interaction between S. pyogenes and human plasminogen may offer novel therapeutic strategies against invasive group A streptococcal infections.

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