title: Sigma s-dependent promoters in Escherichia coli are located in DNA regions with intrinsic curvature.
abstract: Expression of a number of genes during stationary phase in Escherichia coli is controlled by the alternative sigma factor sigma s (KatF). Promoters recognized by sigma s do not present a well-defined consensus sequence in their -10 and -35 regions. By polyacrylamide gel electrophoresis of DNA fragments performed at different temperatures, and by computer prediction analyses, we have found that sigma s-regulated promoters are located in regions where DNA shows intrinsic curvatures. This feature does not appear in a stationary-phase-induced promoter which is not controlled by sigma s. We propose that DNA bending may help in recognition and/or binding of sigma s to stationary-phase-induced promoters.
authors.affiliation: Departamento de Bioquímica y Biología Molecular I, Facultad de Ciencias Químicas, Universidad Complutense, Madrid, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Espinosa-Urgel
authors.forename: A
authors.initials: A
authors.lastname: Tormo
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D001430:Bacteriocins / Q000235:genetics; D003198:Computer Simulation; D004269:DNA, Bacterial / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000235:genetics*; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D011401:Promoter Regions, Genetic; D012808:Sigma Factor / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D001430:Bacteriocins; D004269:DNA, Bacterial; D012808:Sigma Factor; C069567:sigma factor KatF protein, Bacteria; C020411:microcin