Prevalence of agr dysfunction among colonizing Staphylococcus aureus strains

J Infect Dis. 2008 Oct 15;198(8):1171-4. doi: 10.1086/592051.

Abstract

Mutations in the staphylococcal virulence regulator gene agr frequently occur during Staphylococcus aureus infection. Whether agr-defective strains are fit for colonization, an important prerequisite for infection, is unknown. Screening by means of assays to detect delta-hemolysin activity and agr autoinducing peptide production indicated that 15 ( approximately 9%) of 160 healthy human subjects were colonized with an agr-defective strain or a mixture of agr-positive and -defective S. aureus strains. The presence of identical agr-defective strains in family members suggests that these strains are transmissible. Additionally, carriage of an agr-defective strain was associated with hospitalization, raising the possibility that such strains may be selected in a nosocomial setting.

MeSH terms

  • Adult
  • Bacterial Proteins / genetics*
  • Bacterial Proteins / metabolism
  • Carrier State / epidemiology*
  • Carrier State / microbiology*
  • Carrier State / transmission
  • Child, Preschool
  • Female
  • Gene Expression Regulation, Bacterial
  • Hemolysin Proteins / genetics
  • Hemolysin Proteins / metabolism
  • Humans
  • Male
  • Mutation
  • Nose / microbiology*
  • Peptides, Cyclic
  • Prevalence
  • Staphylococcal Infections / epidemiology*
  • Staphylococcal Infections / microbiology*
  • Staphylococcal Infections / transmission
  • Staphylococcus aureus / genetics
  • Staphylococcus aureus / growth & development
  • Staphylococcus aureus / isolation & purification*
  • Trans-Activators / genetics*
  • Trans-Activators / metabolism

Substances

  • Agr protein, Staphylococcus aureus
  • AgrD protein, Staphylococcus
  • Bacterial Proteins
  • Hemolysin Proteins
  • Peptides, Cyclic
  • Trans-Activators
  • delta hemolysin protein, Staphylococcus aureus