RcsB plays a central role in H-NS-dependent regulation of motility and acid stress resistance in Escherichia coli.
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.
Krin
Evelyne
E
Institut Pasteur, Unité de Génétique des Génomes Bactériens, CNRS URA2171, 28 Rue du Docteur Roux, 75724 Paris Cedex 15, France. ekrin@pasteur.fr
Danchin
Antoine
A
Soutourina
Olga
O
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*
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