title: The sigma subunit conserved region 3 is part of "5'-face" of active center of Escherichia coli RNA polymerase.
abstract: Ribonucleotide analogs bound in the initiating site of Escherichia coli RNA polymerase holoenzyme in open promoter complexes were cross-linked to the beta and sigma 70 subunits. Using limited proteolysis and chemical degradation, the cross-link site in sigma 70 was mapped to a segment between amino acids Glu508 and Met561 containing the C-terminal part of conserved region 3. This result, when reconciled with genetic data on the interaction of sigma 70 conserved regions 2 and 4 with the -10 and -35 promoter regions, respectively, allows us to model the orientation of the sigma 70 subunit domains within the open promoter complex.
authors.affiliation: Public Health Research Institute, New York, New York 10016.
authors.forename: K
authors.initials: K
authors.lastname: Severinov
authors.forename: D
authors.initials: D
authors.lastname: Fenyö
authors.forename: E
authors.initials: E
authors.lastname: Severinova
authors.forename: A
authors.initials: A
authors.lastname: Mustaev
authors.forename: B T
authors.initials: BT
authors.lastname: Chait
authors.forename: A
authors.initials: A
authors.lastname: Goldfarb
authors.forename: S A
authors.initials: SA
authors.lastname: Darst
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D017124:Conserved Sequence; D003488:Cyanogen Bromide; D012321:DNA-Directed RNA Polymerases / Q000737:chemistry / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology*; D006868:Hydrolysis; D010446:Peptide Fragments / Q000378:metabolism; D012808:Sigma Factor / Q000378:metabolism; D014357:Trypsin
chemical_list: D010446:Peptide Fragments; D012808:Sigma Factor; C081775:RNA polymerase sigma 70; D012321:DNA-Directed RNA Polymerases; D014357:Trypsin; D003488:Cyanogen Bromide