title: Ubiquinone deficiency in an auxotroph of Escherichia coli requiring 4-hydroxybenzoic acid.
abstract: 1. Escherichia coli 156:53D2 synthesized ubiquinone only when the growth medium was supplemented with 4-hydroxybenzoate acid. 2. Little or no vitamin K(2) was formed by the mutant under the growth conditions employed, in contrast with wild-type strains. 3. In the mutant ubiquinone deficiency was correlated with low respiration and with low particulate NADH-oxidase and NADH-cytochrome b(1)-reductase activity. 4. Preincubation of ubiquinone-deficient particles with ubiquinone-30 largely restored the NADH-oxidase and NADH-cytochrome b(1)-reductase activities. 5. Various NADH-dye-linked reductases which may be associated with NADH dehydrogenase were not affected by the absence of ubiquinone. 6. The succinate-oxidase complex was less affected than the particulate NADH oxidase by ubiquinone deficiency. 7. A pathway for electrons in the NADH-oxidase complex of the auxotroph of E. coli is proposed and its relationship to the pathway in the wild-type strain is discussed.
mesh_terms: D001565:Benzoates / Q000378:metabolism*; D003470:Culture Media; D003486:Cyanides / Q000494:pharmacology; D004579:Electron Transport; D004926:Escherichia coli / Q000201:enzymology / Q000378:metabolism*; D008967:Molecular Biology; D009154:Mutation; D009243:NAD; D009285:Naphthoquinones / Q000494:pharmacology; D010088:Oxidoreductases / Q000378:metabolism*; D011804:Quinolines / Q000494:pharmacology; D013053:Spectrophotometry; D014451:Ubiquinone / Q000378:metabolism*
chemical_list: D001565:Benzoates; D003470:Culture Media; D003486:Cyanides; D009285:Naphthoquinones; D011804:Quinolines; D009243:NAD; D014451:Ubiquinone; D010088:Oxidoreductases