title: Mutations in Bacillus subtilis PyrR, the pyr regulatory protein, with defects in regulation by pyrimidines.
abstract: The pyrimidine nucleotide biosynthetic (pyr) operon in Bacillus subtilis is regulated by a transcriptional attenuation mechanism in which PyrR, a bifunctional pyr RNA-binding attenuation protein/uracil phosphoribosyltransferase, plays a crucial role. A convenient procedure for isolation of pyrR mutants with defects in the regulation of pyr operon expression is described. The selection is based on the selection of spontaneous mutations that convert the pyrimidine-sensitive growth of cpa strain (lacking arginine-repressible carbamyl phosphate synthetase) to pyrimidine resistance. Twelve such mutants were isolated and sequenced. All resulted from point mutations in the pyrR gene.
authors.affiliation: Department of Biochemistry, University of Illinois, Urbana 61801, USA.
authors.forename: S Y
authors.initials: SY
authors.lastname: Ghim
authors.forename: R L
authors.initials: RL
authors.lastname: Switzer
mesh_terms: D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D017931:DNA Primers / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D009154:Mutation; D009876:Operon; D010430:Pentosyltransferases / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011742:Pyrimidine Nucleotides / Q000096:biosynthesis; D011743:Pyrimidines / Q000378:metabolism / Q000494:pharmacology; D012097:Repressor Proteins / Q000235:genetics*; D017386:Sequence Homology, Amino Acid
chemical_list: D001426:Bacterial Proteins; D017931:DNA Primers; D004269:DNA, Bacterial; D011742:Pyrimidine Nucleotides; D011743:Pyrimidines; D012097:Repressor Proteins; D010430:Pentosyltransferases; C098851:PyrR protein, bacteria