Mutational analysis of the group A streptococcal operon encoding streptolysin S and its virulence role in invasive infection

@article{Datta2005MutationalAO,
  title={Mutational analysis of the group A streptococcal operon encoding streptolysin S and its virulence role in invasive infection},
  author={Vivekananda Datta and Sandra M Myskowski and Laura A Kwinn and Daniel N Chiem and Nissi Varki and Rita Kansal and Malak Kotb and Victor Nizet},
  journal={Molecular Microbiology},
  year={2005},
  volume={56}
}
The pathogen group A Streptococcus (GAS) produces a wide spectrum of infections including necrotizing fasciitis (NF). Streptolysin S (SLS) produces the hallmark β‐haemolytic phenotype produced by GAS. The nine‐gene GAS locus (sagA–sagI) resembling a bacteriocin biosynthetic operon is necessary and sufficient  for  SLS  production.  Using  precise,  in‐frame allelic exchange mutagenesis and single‐gene complementation, we show sagA, sagB, sagC, sagD, sagE, sagF and sagG are each individually… Expand
Genetic Characterization and Virulence Role of the RALP3/LSA Locus Upstream of the Streptolysin S Operon in Invasive M1T1 Group A Streptococcus
TLDR
First mutational analysis of a genetic locus immediately upstream of the streptolysin S biosynthetic operon in several GAS genome sequences, identifying RALP3 as a global transcriptional regulator affecting expression of numerous virulence factor genes, including those for strong repression of the hyaluronic acid capsule and cysteine protease production. Expand
Streptococcus iniae beta-hemolysin streptolysin S is a virulence factor in fish infection.
TLDR
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TLDR
Using a genomic mutagenesis strategy, a gene cluster with high homology to the genes of the streptolysin S (SLS) encoding sag gene cluster of S.anginosus is determined and its importance for β-haemolysin production in S. anginous is demonstrated. Expand
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TLDR
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TLDR
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ABSTRACT Group A streptococcus (GAS) is an important human pathogen that causes pharyngitis and invasive infections, including necrotizing fasciitis. Streptolysin S (SLS) is the cytolytic factor thatExpand
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TLDR
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TLDR
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TLDR
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TLDR
It is discovered that csrR mutants have enhanced transcription of sagA, a gene associated with streptolysin S (SLS) and speB, the gene encoding pyrogenic exotoxin B (SpeB) and the mutants also express substantially higher SLS activity and SpeB antigen in late-exponential-phase cultures. Expand
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