title: The lrp gene product regulates expression of lysU in Escherichia coli K-12.
abstract: In Escherichia coli K-12, expression of the lysU gene is regulated by the lrp gene product, as indicated by an increase in the level of lysyl-tRNA synthetase activity and LysU protein in an lrp mutant. Comparison of the patterns of protein expression visualized by two-dimensional gel electrophoresis indicated that LysU is present at higher levels in an lrp strain than in its isogenic lrp+ parent. The purified lrp gene product was shown to bind to sites upstream of the lysU gene and to protect several sites against DNase I digestion. A region extending over 100 nucleotides, between 60 and 160 nucleotides upstream from the start of the lysU coding sequence, showed altered sensitivity to DNase I digestion in the presence of the Lrp protein. The extent of protected DNA suggests a complex interaction of Lrp protein and upstream lysU DNA.
authors.affiliation: Biology Department, Concordia University, Montreal, Quebec, Canada.
authors.forename: R
authors.initials: R
authors.lastname: Lin
authors.forename: B
authors.initials: B
authors.lastname: Ernsting
authors.forename: I N
authors.initials: IN
authors.lastname: Hirshfield
authors.forename: R G
authors.initials: RG
authors.lastname: Matthews
authors.forename: F C
authors.initials: FC
authors.lastname: Neidhardt
authors.forename: R L
authors.initials: RL
authors.lastname: Clark
authors.forename: E B
authors.initials: EB
authors.lastname: Newman
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics*; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial / Q000235:genetics*; D051756:Leucine-Responsive Regulatory Protein; D008250:Lysine-tRNA Ligase / Q000235:genetics*; D008969:Molecular Sequence Data; D016296:Mutagenesis; D014176:Protein Biosynthesis; D012045:Regulatory Sequences, Nucleic Acid / Q000235:genetics*; D014157:Transcription Factors
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; C497278:Lrp protein, E coli; D014157:Transcription Factors; D051756:Leucine-Responsive Regulatory Protein; D008250:Lysine-tRNA Ligase