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… 
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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.
Streptococcus iniae beta-hemolysin streptolysin S is a virulence factor in fish infection.
TLDR
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TLDR
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TLDR
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TLDR
CcpA acts to repress SLS activity and virulence during systemic infection in mice, revealing an important link between carbon metabolism and GAS pathogenesis.
The Abi-domain Protein Abx1 Interacts with the CovS Histidine Kinase to Control Virulence Gene Expression in Group B Streptococcus
TLDR
A regulatory function is reported for Abx1, a member of a large protein family with a characteristic Abi-domain, which forms a signaling complex with the histidine kinase CovS in GBS, a leading cause of invasive infections in neonates.
Study of streptococcal hemoprotein receptor (Shr) in iron acquisition and virulence of M1T1 group A streptococcus
TLDR
It is concluded that Shr augments GAS adherence to laminin, an important extracellular matrix attachment component, which contributes to GAS growth in human blood, and is required for full virulence of serotype M1T1 GAS in mouse models of invasive disease.
A Conserved UDP-Glucose Dehydrogenase Encoded outside the hasABC Operon Contributes to Capsule Biogenesis in Group A Streptococcus
TLDR
It is concluded that HasB is not essential for M1T1 GAS capsule biogenesis due to the presence of a newly identified HasB paralog, HasB2, which most likely resulted from gene duplication.
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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 that
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