title: Molecular analysis of OmpR binding sequences involved in the regulation of ompF in Escherichia coli.
abstract: OmpR, the transcriptional regulatory protein of ompF, had not been previously shown to specifically bind to the -70 to -60-bp region of ompF. We show that the -102 to -76-bp sequence of ompF has a high affinity binding site for OmpR and produced a single OmpR/ompF complex (complex b). Extension of this DNA fragment to include an inverted repeat sequence located between the -71 and -64-bp region resulted in the formation of a second, slower migrating complex (complex a). A -102 to -58-bp fragment containing a substitution of the -70 CG bp was able to form complex b, but not complex a. A mutant OmpR protein derived from a strain that can not repress ompF was unable to form complex a, while complex b was formed normally. Deletion of the -70 CG bp resulted in incomplete repression of OmpF. These results suggest that OmpR binds to the -71 to -64-bp region and that this sequence plays a role in the regulation of ompF in Escherichia coli.
authors.affiliation: Department of Biological Sciences, University of Wisconsin-Milwaukee 53201, USA.
authors.forename: S
authors.initials: S
authors.lastname: Forst
authors.forename: I
authors.initials: I
authors.lastname: Kalve
authors.forename: W
authors.initials: W
authors.lastname: Durski
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000235:genetics* / Q000378:metabolism*; D001483:Base Sequence; D001665:Binding Sites; D004269:DNA, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D011485:Protein Binding; D017384:Sequence Deletion
chemical_list: D001425:Bacterial Outer Membrane Proteins; D004269:DNA, Bacterial