title: Restored DNA-binding of the cAMP-CRP activator complex reestablishes negative regulation by the CytR repressor in the deoP2 promoter in Escherichia coli.
abstract: We have investigated in vivo the coupling between CytR regulation of the deoP2 promoter in Escherichia coli and the DNA-binding specificity of the cAMP-CRP (cAMP receptor protein) complex in order to obtain a more detailed picture of the role played by cAMP-CRP in CytR regulation. By introducing CRP proteins that exhibit an altered DNA binding specificity into a strain containing a mutant deoP2 promoter in which cAMP-CRP activation was decreased and CytR regulation completely abolished, we show that CytR regulation of this promoter can be reestablished by restored the DNA binding of the cAMP-CRP complex. Hence, CytR regulation of deoP2 can be modulated by simply varying DNA binding of cAMP-CRP. These data confirm the crucial role played by the cAMP-CRP activator complex in CytR regulation of the deoP2 promoter.
authors.affiliation: Department of Molecular Biology, Odense University, Denmark.
authors.forename: L
authors.initials: L
authors.lastname: Søgaard-Andersen
authors.forename: P
authors.initials: P
authors.lastname: Valentin-Hansen
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D001483:Base Sequence; D002352:Carrier Proteins / Q000378:metabolism*; D000242:Cyclic AMP / Q000378:metabolism; D002373:Cyclic AMP Receptor Protein; D004269:DNA, Bacterial / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics*; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial / Q000235:genetics*; D008969:Molecular Sequence Data; D010957:Plasmids / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000502:physiology*; D011953:Receptors, Cyclic AMP / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D012097:Repressor Proteins / Q000378:metabolism / Q000502:physiology*; D015719:Single-Strand Specific DNA and RNA Endonucleases / Q000378:metabolism; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D002373:Cyclic AMP Receptor Protein; C048425:CytR protein, E coli; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D011953:Receptors, Cyclic AMP; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; D000242:Cyclic AMP; D015719:Single-Strand Specific DNA and RNA Endonucleases; D001616:beta-Galactosidase