title: CcpA mediates the catabolite repression of tst in Staphylococcus aureus.
abstract: Some clinical isolates of Staphylococcus aureus produce the superantigenic toxic shock syndrome toxin 1 (TSST-1), encoded by tst, located on pathogenicity islands. The expression of tst is complex and is influenced by environmental conditions such as pH, CO(2), and glucose. We identified a putative catabolite-responsive element (cre) in the promoter regions of all known tst genes, indicating that tst transcription may be regulated by the catabolite control protein CcpA. By introducing tst genes under the control of their native promoters or tst promoter-reporter gene fusions in wild-type strain Newman, we showed that glucose was able to repress tst transcription and TSST-1 production, whereas glucose repression was abolished in the corresponding Delta ccpA mutant. Stabilizing the pH ruled out a pH effect due to acid production during glucose catabolism. CcpA thus directly regulates tst transcription, linking carbohydrate utilization to virulence gene expression in S. aureus.
authors: Institute of Medical Microbiology, University of Zurich, 8006 Zurich, Switzerland.
authors: Kati
authors: K
authors: Seidl
authors: Markus
authors: M
authors: Bischoff
authors: Brigitte
authors: B
authors: Berger-Bächi
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D001427:Bacterial Toxins / Q000235:genetics*; D015152:Blotting, Northern; D015153:Blotting, Western; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004768:Enterotoxins / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D005947:Glucose / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics; D012097:Repressor Proteins / Q000378:metabolism*; D020218:Response Elements / Q000235:genetics*; D013211:Staphylococcus aureus / Q000235:genetics* / Q000472:pathogenicity; D018089:Superantigens / Q000235:genetics*; D037521:Virulence Factors / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004268:DNA-Binding Proteins; D004768:Enterotoxins; D012097:Repressor Proteins; D018089:Superantigens; D037521:Virulence Factors; C069286:catabolite control proteins, bacteria; C030107:enterotoxin F, Staphylococcal; D005947:Glucose