coli HN280 [32]. Conclusion In E. coli, the control of acid stress resistance is achieved by the concerted efforts of multiple regulators and overlapping systems, most of the genes directly involved in acid resistance being both controlled by RcsB-P/GadE complex and by at least one other regulator such as H-NS, HdfR, CadC or AdiY. Acknowledgements We thank Nathalie Sassoon for help in protein purifications

and Zeynep Baharoglu for critical reading of the manuscript. Financial support came from the Institut Pasteur, the Centre National de la Recherche Scientifique (URA 2171) and the Probactys NEST European programme, grant CT-2006-029104. OS is assistant find more professor at the Université Paris 7. Electronic supplementary material Additional File 1: List of primers used in learn more real-time quantitative RT-PCR experiments. (DOC 24 KB) Additional File 2: List of primers used for gels retardation assay. (DOC 199 KB) References 1. Hommais F, Krin E, Laurent-Winter C, Soutourina O, Malpertuy A, Le Caer JP, Danchin A, Bertin P: Large-scale monitoring of pleiotropic regulation of gene expression

by the prokaryotic nucleoid-associated protein, H-NS. Mol Microbiol 2001,40(1):20–36.PubMedCrossRef selleck products 2. Francez-Charlot A, Laugel B, Van Gemert A, Dubarry N, Wiorowski F, Castanie-Cornet MP, Gutierrez C, Cam K: RcsCDB His-Asp phosphorelay system negatively regulates the flhDC operon in Escherichia coli . Mol Microbiol 2003,49(3):823–832.PubMedCrossRef 3. Ko M, Park C: H-NS-Dependent regulation of flagellar synthesis is mediated by a LysR family protein. J Bacteriol 2000,182(16):4670–4672.PubMedCrossRef 4. Soutourina O, Kolb A, Krin E, Laurent-Winter C, 4��8C Rimsky S, Danchin A, Bertin P: Multiple control of flagellum biosynthesis

in Escherichia coli : role of H-NS protein and the cyclic AMP-catabolite activator protein complex in transcription of the flhDC master operon. J Bacteriol 1999,181(24):7500–7508.PubMed 5. Soutourina OA, Krin E, Laurent-Winter C, Hommais F, Danchin A, Bertin PN: Regulation of bacterial motility in response to low pH in Escherichia coli : the role of H-NS protein. Microbiology 2002,148(5):1543–1551.PubMed 6. Krin E, Danchin A, Soutourina O: RcsB plays a central role in H-NS-dependent regulation of motility and acid stress resistance in Escherichia coli . Res Microbiol 2010,161(5):363–371.PubMedCrossRef 7. Masuda N, Church GM: Regulatory network of acid resistance genes in Escherichia coli . Mol Microbiol 2003,48(3):699–712.PubMedCrossRef 8. Sayed AK, Odom C, Foster JW: The Escherichia coli AraC-family regulators GadX and GadW activate gadE , the central activator of glutamate-dependent acid resistance. Microbiology 2007,153(8):2584–2592.PubMedCrossRef 9. Atlung T, Ingmer H: H-NS: a modulator of environmentally regulated gene expression. Mol Microbiol 1997,24(1):7–17.PubMedCrossRef 10.