These two authors contributed equally to this work.
RcsCDB His-Asp phosphorelay system negatively regulates the flhDC operon in Escherichia coli
Article first published online: 28 JAN 2004
Volume 49, Issue 3, pages 823–832, August 2003
How to Cite
Francez-Charlot, A., Laugel, B., Van Gemert, A., Dubarry, N., Wiorowski, F., Castanié-Cornet, M.-P., Gutierrez, C. and Cam, K. (2003), RcsCDB His-Asp phosphorelay system negatively regulates the flhDC operon in Escherichia coli. Molecular Microbiology, 49: 823–832. doi: 10.1046/j.1365-2958.2003.03601.x
- Issue published online: 28 JAN 2004
- Article first published online: 28 JAN 2004
- Accepted 22 April, 2003.
The genes involved in flagellum synthesis, motility and chemotaxis in Escherichia coli are expressed in a hierarchical fashion. At the top of the hierarchy lies the master regulator FlhDC, required for the expression of the whole set of genes. The operon flhDC is controlled by numerous regulators including H-NS, CRP, EnvZ/OmpR, QseBC and LrhA. In the present work, we report that the flhDC operon is also negatively regulated by the His-Asp phosphorelay system RcsCDB. The regulation is potentiated by the RcsB cofactor RcsA. Genetic analysis indicates that an RcsAB box, located downstream of the promoter, is required for the regulation. The binding of RcsB and RcsA to this site was demonstrated by gel retardation and DNase I protection assays. In addition, mutation analysis suggests that RcsA-specific determinants lie in the right part of the ‘RcsAB box’.