title: Genetic characterization of the pnuC gene, which encodes a component of the nicotinamide mononucleotide transport system in Salmonella typhimurium.
abstract: The pnuC gene, which encodes a component of the nicotinamide mononucleotide transport system, has been mapped and oriented. The gene order of the pnuC region, which is at min 17 of the Salmonella chromosome, is nadA-pnuC-aroG-gal. Polarity tests, with pnuC::Mu d-lac operon fusions, reveal that the pnuC gene is the promoter distal gene in an operon with the nadA gene, which encodes the second enzyme of the pyridine biosynthetic pathway. The nadA pnuC operon is regulated by the NadI repressor. The pnuC gene also has its own promoter, since strains with a nadA::Tn10d(Tc) insertion still express the pnuC gene at a low, unregulated level.
authors.affiliation: Department of Biology, University of Utah, Salt Lake City 84112.
authors.forename: N
authors.initials: N
authors.lastname: Zhu
authors.forename: B M
authors.initials: BM
authors.lastname: Olivera
authors.forename: J R
authors.initials: JR
authors.lastname: Roth
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics*; D001692:Biological Transport; D002872:Chromosome Deletion; D004251:DNA Transposable Elements; D005796:Genes; D005798:Genes, Bacterial; D005838:Genotype; D009154:Mutation; D009537:Nicotinamide Mononucleotide / Q000378:metabolism*; D011995:Recombination, Genetic; D012486:Salmonella typhimurium / Q000235:genetics* / Q000378:metabolism; D014161:Transduction, Genetic
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D009537:Nicotinamide Mononucleotide