title: The pdhR-aceEF-lpd operon of Escherichia coli expresses the pyruvate dehydrogenase complex.
abstract: Transcript mapping and studies with lacZ translational fusions have shown that the pdhR gene (formerly genA) is the proximal gene of the pdhR-aceE-aceF-lpd operon encoding the pyruvate dehydrogenase (PDH) complex of Escherichia coli. A pdhR-lpd read-through transcript (7.4 kb) initiating at the pyruvate-inducible pdh promoter, and a smaller lpd transcript (1.7 kb) initiating at the independent lpd promoter, were identified. Evidence showing that the pdhR gene product negatively regulates the synthesis of the PdhR protein and the PDH complex via the pdh promoter was obtained, with pyruvate (or a derivative) serving as the putative inducing coeffector. The partially purified PdhR protein was also found to specifically retard and protect DNA fragments containing the pdh promoter region. The pdh promoter was not strongly controlled by ArcA, FNR or CRP.
authors.affiliation: Krebs Institute, Department of Molecular Biology and Biotechnology, University of Sheffield, UK.
authors.forename: M A
authors.initials: MA
authors.lastname: Quail
authors.forename: D J
authors.initials: DJ
authors.lastname: Haydon
authors.forename: J R
authors.initials: JR
authors.lastname: Guest
mesh_terms: D000123:Acetyltransferases / Q000096:biosynthesis / Q000235:genetics*; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D004269:DNA, Bacterial / Q000235:genetics / Q000378:metabolism; D008058:Dihydrolipoamide Dehydrogenase / Q000096:biosynthesis / Q000235:genetics*; D051047:Dihydrolipoyllysine-Residue Acetyltransferase; D004790:Enzyme Induction; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D007655:Ketoglutarate Dehydrogenase Complex / Q000096:biosynthesis / Q000235:genetics*; D008969:Molecular Sequence Data; D009876:Operon; D011401:Promoter Regions, Genetic; D011768:Pyruvate Dehydrogenase Complex / Q000096:biosynthesis / Q000235:genetics*; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D012045:Regulatory Sequences, Nucleic Acid; D012097:Repressor Proteins / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; C084955:PdhR protein, E coli; D011768:Pyruvate Dehydrogenase Complex; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; D007655:Ketoglutarate Dehydrogenase Complex; C088796:lpd protein, E coli; D008058:Dihydrolipoamide Dehydrogenase; D000123:Acetyltransferases; D051047:Dihydrolipoyllysine-Residue Acetyltransferase