title: A mutation causing constitutive synthesis of the pyruvate dehydrogenase complex in Escherichia coli is located within the pdhR gene.
abstract: The aceE-aceF-lpd genes encoding the pyruvate dehydrogenase (PDH) complex of Escherichia coli are preceded by a gene encoding a putative transcriptional regulator, PdhR (formerly designated GenA). Enzymological tests and studies with pdhR-lacZ and aceE-lacZ translational fusions have shown that a constitutive mutation (acec816), which increases PDH complex synthesis to the pyruvate-induced level in the absence of inducer, is recessive to the wild-type pdhR gene in trans. Sequence comparisons further showed that the acec816 mutation affects a single site in the pdhR gene leading to an Arg118 (CGU)-->Cys (UGU) substitution in the PdhR protein. The results support the view that synthesis of the PDH complex is regulated from the pdhR promoter of a pdhR-aceEF-lpd operon.
authors.affiliation: Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, UK.
authors.forename: D J
authors.initials: DJ
authors.lastname: Haydon
authors.forename: M A
authors.initials: MA
authors.lastname: Quail
authors.forename: J R
authors.initials: JR
authors.lastname: Guest
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial; D005809:Genes, Regulator; D008969:Molecular Sequence Data; D009154:Mutation; D010957:Plasmids; D014176:Protein Biosynthesis; D011768:Pyruvate Dehydrogenase Complex / Q000096:biosynthesis* / Q000235:genetics; D012097:Repressor Proteins; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; C084955:PdhR protein, E coli; D011768:Pyruvate Dehydrogenase Complex; D012097:Repressor Proteins; D014157:Transcription Factors