title: Disruption of narG, the gene encoding the catalytic subunit of respiratory nitrate reductase, also affects nitrite respiration in Pseudomonas fluorescens YT101.
abstract: The Pseudomonas fluorescens YT101 gene narG, which encodes the catalytic alpha subunit of the respiratory nitrate reductase, was disrupted by insertion of a gentamicin resistance cassette. In the Nar(-) mutants, nitrate reductase activity was not detectable under all the conditions tested, suggesting that P. fluorescens YT101 contains only one membrane-bound nitrate reductase and no periplasmic nitrate reductase. Whereas N(2)O respiration was not affected, anaerobic growth with NO(2) as the sole electron acceptor was delayed for all of the Nar(-) mutants following a transfer from oxic to anoxic conditions. These results provide the first demonstration of a regulatory link between nitrate and nitrite respiration in the denitrifying pathway.
authors.affiliation: Laboratoire d'Ecologie Microbienne du Sol, UMR C.N.R.S. 5557, Université Claude Bernard, Lyon 1, 69622 Villeurbanne Cedex, France.
authors.forename: J F
authors.initials: JF
authors.lastname: Ghiglione
authors.forename: L
authors.initials: L
authors.lastname: Philippot
authors.forename: P
authors.initials: P
authors.lastname: Normand
authors.forename: R
authors.initials: R
authors.lastname: Lensi
authors.forename: P
authors.initials: P
authors.lastname: Potier
mesh_terms: D000693:Anaerobiosis; D015153:Blotting, Western; D020134:Catalytic Domain; D015964:Gene Expression Regulation, Bacterial; D015971:Gene Expression Regulation, Enzymologic; D016296:Mutagenesis; D050901:Nitrate Reductase; D009565:Nitrate Reductases / Q000032:analysis / Q000235:genetics* / Q000378:metabolism*; D009566:Nitrates / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism*; D010957:Plasmids; D011551:Pseudomonas fluorescens / Q000201:enzymology* / Q000235:genetics* / Q000254:growth & development
chemical_list: D009566:Nitrates; D009573:Nitrites; D009565:Nitrate Reductases; D050901:Nitrate Reductase