title: RcsB plays a central role in H-NS-dependent regulation of motility and acid stress resistance in Escherichia coli.
abstract: In Escherichia coli, hns mutants lack flagellar motility and display an increase in acid stress resistance. Spontaneous phenotypic revertants showed reversion of both H-NS-controlled phenotypes. In the present study, suppressor mutations were identified in the rcsB gene. In addition to RcsA, our experiments establish that H-NS indirectly controlled the RcsB regulator via repression of RcsD. We also show that RcsB(D56E), mimicking phosphorylated RcsB, interacts with GadE to form a RcsB-P/GadE complex, a general direct regulator of glutamate-, arginine- and lysine-dependent acid resistance pathways. In addition, we showed that H-NS positively affects motility via the flhDC master operon repression by RcsB. This substantiates the central role of RcsB in H-NS-mediated control of motility and acid stress resistance.
authors.affiliation: Institut Pasteur, Unité de Génétique des Génomes Bactériens, CNRS URA2171, 28 Rue du Docteur Roux, 75724 Paris Cedex 15, France. ekrin@pasteur.fr
authors.forename: Evelyne
authors.initials: E
authors.lastname: Krin
authors.forename: Antoine
authors.initials: A
authors.lastname: Danchin
authors.forename: Olga
authors.initials: O
authors.lastname: Soutourina
mesh_terms: D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D036781:Fimbriae Proteins / Q000235:genetics / Q000378:metabolism*; D005407:Flagella / Q000235:genetics* / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D009068:Movement; D009876:Operon; D010766:Phosphorylation; D010770:Phosphotransferases / Q000235:genetics / Q000378:metabolism*; D050436:Regulatory Elements, Transcriptional; D013312:Stress, Physiological; D013489:Suppression, Genetic; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D029968:Escherichia coli Proteins; C529458:FimG protein, E coli; C479562:GadE protein, E coli; C489568:RcsB protein, E coli; D015534:Trans-Activators; D014157:Transcription Factors; C090552:flhC protein, E coli; C090553:flhD protein, E coli; D036781:Fimbriae Proteins; D010770:Phosphotransferases; C434271:rcsD protein, E coli