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Published on: August 19, 2016
Streptolysin S-like virulence factors: the continuing sagA
Evelyn M Molloy1, Paul D Cotter, Colin Hill
1Department of Microbiology, University College Cork, Cork, Ireland.
Nature Reviews. Microbiology
|August 9, 2011
Summary
Streptolysin S (SLS) is a key toxin from Streptococcus pyogenes. Recent research reveals SLS is part of a larger family of related virulence factors found in various Gram-positive pathogens.
Area of Science:
- Microbiology
- Molecular Biology
- Toxicology
Background:
- Streptolysin S (SLS) is a well-known cytolytic toxin and virulence factor produced by Streptococcus pyogenes.
- Despite extensive research over a century, the full scope of SLS and its related toxins has only recently been understood.
Purpose of the Study:
- To review the identification, genetics, biochemistry, and functions of Streptolysin S.
- To discuss the shared characteristics of SLS-like peptides and their classification within the broader thiazole/oxazole-modified microcins (TOMMs) family.
Main Methods:
- Literature review of existing research on Streptolysin S and related peptides.
- Analysis of genetic and biochemical data for SLS and SLS-like virulence factors.
- Comparative analysis of virulence factors across different Gram-positive pathogens.
Main Results:
- SLS is one member of an extended family of post-translationally modified virulence factors, termed SLS-like peptides.
- These peptides are produced by various streptococci and other Gram-positive pathogens, including Listeria monocytogenes and Clostridium botulinum.
- SLS-like peptides share common features and are part of the expanding group of thiazole/oxazole-modified microcins (TOMMs).
Conclusions:
- The understanding of Streptolysin S has evolved beyond a single toxin to a family of related virulence factors.
- SLS-like peptides represent a significant class of virulence factors in Gram-positive bacterial pathogens.
- Further research into TOMMs will illuminate their roles in pathogenesis and potential as therapeutic targets.
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