PhoP-responsive expression of the Salmonella enterica serovar typhimurium slyA gene.
The SlyA protein of Salmonella enterica serovar Typhimurium is a member of the MarR family of transcription regulators and is required for virulence and survival in professional macrophages. Isolated SlyA protein was able to bind a specific DNA target without posttranslational modification. This suggested that SlyA might not be activated by directly sensing an external signal but rather that the intracellular concentration of SlyA is enhanced in appropriate environments through the action of other transcription factors. Analysis of slyA transcription reveals the presence of a promoter region located upstream of the previously recognized SlyA repressed promoter. The newly identified upstream promoter region did not respond to SlyA but was activated by Mg(II) starvation in a PhoP-dependent manner. We present here evidence for a direct link between two transcription factors (PhoP and SlyA) crucial for Salmonella virulence.
Norte
Valia A
VA
Department of Molecular Biology and Biotechnology, Krebs Institute for Biomolecular Research, University of Sheffield, Sheffield S10 2TN, United Kingdom.
Stapleton
Melanie R
MR
Green
Jeffrey
J
D001426:Bacterial Proteins / Q000235:genetics*; D001427:Bacterial Toxins / Q000096:biosynthesis / Q000235:genetics*; D001483:Base Sequence; D003470:Culture Media; D015964:Gene Expression Regulation, Bacterial; D006460:Hemolysin Proteins / Q000096:biosynthesis / Q000235:genetics*; D008274:Magnesium; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D012486:Salmonella typhimurium / Q000235:genetics* / Q000254:growth & development / Q000472:pathogenicity; D014157:Transcription Factors / Q000235:genetics*; D014774:Virulence
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D003470:Culture Media; D006460:Hemolysin Proteins; D014157:Transcription Factors; C056785:salmolysin; C061064:PhoP protein, Bacteria; D008274:Magnesium