Link to Pubmed [PMID] – 20435136
Res. Microbiol. 2010 Jun;161(5):363-71
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.