Comparison of PhoP binding to the tuaA promoter with PhoP binding to other Pho-regulon promoters establishes a Bacillus subtilis Pho core binding site.
The phosphate-deficiency response in Bacillus subtilis is regulated by PhoP and PhoR, a pair of two-component regulatory proteins. PhoR is a histidine kinase and PhoP is a response regulator. Genetic evidence indicates that the Pho-regulon genes, which are induced or repressed under phosphate starvation conditions, are regulated by PhoP and PhoR at the transcriptional level. It has previously been shown that PhoP binds to four Pho-regulon promoters in both unphosphorylated and phosphorylated forms. This study demonstrates that another Pho-regulon gene promoter, the tuaA promoter preceding the operon which is responsible for cell wall teichuronic acid synthesis, is also transcriptionally regulated and is bound by PhoP. The binding affinity for phosphorylated PhoP was about 10-fold higher than that for unphosphorylated PhoP. Both unphosphorylated and phosphorylated PhoP bound upstream of the -20 region in the tuaA promoter. By aligning the PhoP-binding sites within the Pho-regulon promoters, a consensus core PhoP-binding region composed of four TT(A/T)ACA direct repeats, each separated by 5 +/- 2 non-conserved nucleotides was identified. PhoP, phosphorylated or unphosphorylated, binds to such a sequence in all Pho-regulon promoters studied. Phosphorylated PhoP binds to the core binding region with high affinity and to additional regions surrounding this region with similar or lower affinity.
Liu
Wei
W
Laboratory for Molecular Biology, Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA.
Hulett
F Marion
FM
Laboratory for Molecular Biology, Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA.
D001412:Bacillus subtilis / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D001426:Bacterial Proteins / Q000378:metabolism*; D001483:Base Sequence; D001665:Binding Sites; D016384:Consensus Sequence; D018983:DNA Footprinting; D004268:DNA-Binding Proteins; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005809:Genes, Regulator; D000071677:Histidine Kinase; D008969:Molecular Sequence Data; D010710:Phosphates / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D011494:Protein Kinases / Q000235:genetics* / Q000378:metabolism*; D018085:Regulon; D017422:Sequence Analysis, DNA; D014157:Transcription Factors / Q000378:metabolism; D014574:Uronic Acids / Q000378:metabolism; D001616:beta-Galactosidase / Q000032:analysis
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D010710:Phosphates; D014157:Transcription Factors; D014574:Uronic Acids; C061064:PhoP protein, Bacteria; C010788:teichuronic acid; D011494:Protein Kinases; D000071677:Histidine Kinase; D001616:beta-Galactosidase