title: Concomitant regulation of host tissue-destroying virulence factors and carbohydrate metabolism during invasive diseases induced by group g streptococci.
abstract: BACKGROUND
  Streptococcus dysgalactiae subsp. equisimilis (SDSE) has Lancefield group G or C antigens. Recent epidemiological studies reveal that invasive SDSE infections have been increasing in Asia, Europe, and the United States. The mechanisms and key virulence factors by which SDSE causes invasive diseases are poorly understood.
  
  
  METHODS
  We analyzed the SDSE transcriptome in vivo during intraperitoneal infection in mice. We also compared the abundance of streptolysin S (SLS) and streptolysin O (SLO) production between clinically dominant stG6792 strains and other clinical isolates.
  
  
  RESULTS
  Microarray data suggest that SDSE degraded host tissue polysaccharides by secreting poly/oligosaccharide lyases and simultaneously used the Entner-Doudoroff pathway to metabolize acquired carbohydrates. A global negative virulence gene regulator CsrRS of SDSE modulated the expression of genes encoding SLS and enzymes that metabolize carbohydrates. Moreover, a csrS-deficient mutant induced severe systemic hemolysis in mice. The most frequently isolated stG6792 strains secreted abundant SLS and SLO rather than other SDSE emm types, indicating the potential relationship between production of SLS and SLO and poor outcomes.
  
  
  CONCLUSIONS
  Our findings suggest that the concomitant regulation of virulence factors that destroy host tissues and metabolic enzymes might play an important role in invasive diseases induced by SDSE.
authors.affiliation: Department of Infectious Diseases, Research Institute, National Center for Global Health and Medicine.
authors.forename: Shinya
authors.initials: S
authors.lastname: Watanabe
authors.forename: Yumi
authors.initials: Y
authors.lastname: Shimomura
authors.forename: Kimiko
authors.initials: K
authors.lastname: Ubukata
authors.forename: Teruo
authors.initials: T
authors.lastname: Kirikae
authors.forename: Tohru
authors.initials: T
authors.lastname: Miyoshi-Akiyama
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D050260:Carbohydrate Metabolism / Q000235:genetics; D005109:Extracellular Matrix / Q000378:metabolism; D005260:Female; D015964:Gene Expression Regulation, Bacterial; D006461:Hemolysis; D054884:Host-Pathogen Interactions; D051379:Mice; D020125:Mutation, Missense; D009244:NAD+ Nucleosidase / Q000235:genetics / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D009876:Operon; D013290:Streptococcal Infections / Q000382:microbiology*; D013291:Streptococcus / Q000201:enzymology* / Q000235:genetics; D013301:Streptolysins / Q000235:genetics / Q000378:metabolism; D059467:Transcriptome; D037521:Virulence Factors / Q000235:genetics* / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D013301:Streptolysins; D037521:Virulence Factors; C025964:streptolysin O; C026050:streptolysin S; D009244:NAD+ Nucleosidase
keywords: Streptococcus dysgalactiae subsp. equisimilis; hemolysin; invasive infection; transcriptome