title: Pleiotropic effects of poxA regulatory mutations of Escherichia coli and Salmonella typhimurium, mutations conferring sulfometuron methyl and alpha-ketobutyrate hypersensitivity.
abstract: A transposon Tn10 insertion into the Salmonella typhimurium poxA gene was identified among a set of mutations conferring sulfometuron methyl (SM) hypersensitivity. This Tn10 insertion mapped to 95 min on the S. typhimurium chromosome, a location analogous to that of poxA in the Escherichia coli genome. Like the E. coli poxA mutant, this mutant had reduced pyruvate oxidase activity, reduced cross-reacting material to antiserum to purified E. coli pyruvate oxidase, and reduced growth rates. In addition, the following phenotypes were identified for the E. coli and S. typhimurium poxA mutants: hypersensitivity to SM and alpha-ketobutyrate (AKB), deficiency in AKB metabolism, reduced activity of acetolactate synthase, and hypersensitivity to a wide range of bacterial growth inhibitors, including antibiotics, amino acid analogs, and dyes. An E. coli mutant defective in poxB, the structural gene encoding pyruvate oxidase, did not have these phenotypes; therefore, they are not solely a consequence of a pyruvate oxidase deficiency. Comparisons were made with mutant alleles of two other genes that are located near poxA and confer related phenotypes. The S. typhimurium poxA mutant differed both genetically and phenotypically from an miaA mutant. E. coli abs mutants had somewhat reduced pyruvate oxidase activity but had normal AKB metabolism. The relationship of the pleiotropic phenotypes of the poxA mutants to their SM hypersensitivity is discussed.
authors.affiliation: Central Research and Development Department, E. I. du Pont de Nemours & Co., Inc., Wilmington, Delaware 19898.
authors.forename: T K
authors.initials: TK
authors.lastname: Van Dyk
authors.forename: D R
authors.initials: DR
authors.lastname: Smulski
authors.forename: Y Y
authors.initials: YY
authors.lastname: Chang
mesh_terms: D000095:Acetolactate Synthase / Q000378:metabolism; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002087:Butyrates / Q000378:metabolism / Q000494:pharmacology*; D055598:Chemical Phenomena; D002621:Chemistry; D003429:Cross Reactions; D003470:Culture Media; D004251:DNA Transposable Elements; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D005796:Genes; D005798:Genes, Bacterial; D005809:Genes, Regulator; D006540:Herbicides / Q000494:pharmacology; D007700:Kinetics; D009154:Mutation; D010641:Phenotype; D011771:Pyruvate Oxidase / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D012486:Salmonella typhimurium / Q000187:drug effects / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D013453:Sulfonylurea Compounds / Q000494:pharmacology*; D014161:Transduction, Genetic
chemical_list: D000900:Anti-Bacterial Agents; D002087:Butyrates; D003470:Culture Media; D004251:DNA Transposable Elements; D006540:Herbicides; D013453:Sulfonylurea Compounds; C005087:alpha-ketobutyric acid; D011771:Pyruvate Oxidase; D000095:Acetolactate Synthase; C042031:sulfometuron methyl