title: Substitutions in the Escherichia coli RNA polymerase sigma70 factor that affect recognition of extended -10 elements at promoters.
abstract: Previous work has shown that the base sequence of the DNA segment immediately upstream of the -10 hexamer at bacterial promoters (the extended -10 element) can make a significant contribution to promoter strength. Guided by recently published structural information, we used alanine scanning and suppression mutagenesis of Region 2.4 and Region 3.0 of the Escherichia coli RNA polymerase sigma(70) subunit to identify amino acid sidechains that play a role in recognition of this element. Our study shows that changes in these regions of the sigma(70) subunit can affect the recognition of different extended -10 element sequences.
authors.affiliation: School of Biosciences, The University of Birmingham, UK.
authors.forename: Andrew
authors.initials: A
authors.lastname: Sanderson
authors.forename: Jennie E
authors.initials: JE
authors.lastname: Mitchell
authors.forename: Stephen D
authors.initials: SD
authors.lastname: Minchin
authors.forename: Stephen J W
authors.initials: SJ
authors.lastname: Busby
mesh_terms: D000409:Alanine / Q000737:chemistry / Q000378:metabolism; D000595:Amino Acid Sequence; D001483:Base Sequence; D012321:DNA-Directed RNA Polymerases / Q000737:chemistry* / Q000235:genetics*; D004926:Escherichia coli / Q000201:enzymology*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016296:Mutagenesis; D009154:Mutation; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012808:Sigma Factor / Q000737:chemistry* / Q000235:genetics*; D014158:Transcription, Genetic
chemical_list: D012808:Sigma Factor; C081775:RNA polymerase sigma 70; D012321:DNA-Directed RNA Polymerases; D000409:Alanine