Staphylococcus aureus CodY negatively regulates virulence gene expression

Charlotte D. Majerczyk, Marat R. Sadykov, Thanh T. Luong, Chia Lee, Greg A Somerville, Abraham L. Sonenshein

Research output: Contribution to journalArticle

113 Scopus citations


CodY is a global regulatory protein that was first discovered in Bacillus subtilis, where it couples gene expression to changes in the pools of critical metabolites through its activation by GTP and branched-chain amino acids. Homologs of CodY can be found encoded in the genomes of nearly all low-G+C gram-positive bacteria, including Staphylococcus aureus. The introduction of a codY-null mutation into two S. aureus clinical isolates, SA564 and UAMS-1, through allelic replacement, resulted in the overexpression of several virulence genes. The mutant strains had higher levels of hemolytic activity toward rabbit erythrocytes in their culture fluid, produced more polysaccharide intercellular adhesin (PIA), and formed more robust biofilms than did their isogenic parent strains. These phenotypes were associated with derepressed levels of RNA for the hemolytic alpha-toxin (hla), the accessory gene regulator (agr) (RNAII and RNAIII/hld), and the operon responsible for the production of PIA (icaADBC). These data suggest that CodY represses, either directly or indirectly, the synthesis of a number of virulence factors of S. aureus.

Original languageEnglish (US)
Pages (from-to)2257-2265
Number of pages9
JournalJournal of bacteriology
Issue number7
Publication statusPublished - Apr 1 2008


ASJC Scopus subject areas

  • Microbiology
  • Molecular Biology

Cite this

Majerczyk, C. D., Sadykov, M. R., Luong, T. T., Lee, C., Somerville, G. A., & Sonenshein, A. L. (2008). Staphylococcus aureus CodY negatively regulates virulence gene expression. Journal of bacteriology, 190(7), 2257-2265.