At least let philosophers do the right thing when we analyze functional characterization: let no philosopher join what science has put asunder.


Table of Contents


Microorganisms are able to thrive in environments differing by their temperature, osmolarity, pH, nutrient availability, etc. by rapidly adapting their structure and physiology. The corresponding processes are based on the existence of multiple regulatory networks that control gene expression in a coordinate manner in response to environmental stimuli, and in particular to changes in the environment.

Among the many genes that coordinate gene expression in gamma-proteobacteria the hns gene is particularly important. It has been characterized as a model system for studying the regulation of bacterial physiology. In Escherichia coli, the H-NS protein is involved in numerous cellular functions, affecting the expression of genes regulated by environmental factors or required in virulence.

Our experiments showed that proteins of the H-NS family are widespread in Gram-negative bacteria. Their structural and functional organization seems to be evolutionarily conserved. In particular, they are organized in two modules: the N-terminal part involved in oligomerization is specific for a bacterial family and linked to the C-terminal DNA-binding domain by a loop. At least in E. coli and related bacteria, H-NS-like proteins play a major role in bacterial physiology by controlling the expression of numerous genes such as those involved in bacterial motility. Most of them are regulated in response to environmental stresses, which suggests a role for H-NS in the maintenance of homeostasis, an essential condition for the survival inside their host.


blueP Lejeune, P Bertin, C Walon, K Willemot, C Colson, A Danchin
A locus involved in kanamycin, chloramphenicol and L-serine resistance is located in the bglY-galU region of the Escherichia coli K12 chromosome
Mol Gen Genet (1989) 218: 361-363 PubMed

blue P Bertin, P Lejeune, C Laurent-Winter, A Danchin
Mutations in bglY, the structural gene for the DNA-binding protein H1, affect expression of several Escherichia coli genes
Biochimie (1990) 72: 889-891 pubmed

blue P Lejeune, A Danchin
Mutations in the bglY gene increase the frequency of spontaneous deletions in Escherichia coli K-12
Proc Natl Acad Sci U S A (1990) 87: 360-363 pubmed

blue P Bertin, P Lejeune, C Colson, A Danchin
Mutations in bglY, the structural gene for the DNA-binding protein H1 of Escherichia coli, increase the expression of the kanamycin resistance gene carried by plasmid pGR71
Mol Gen Genet (1992) 233: 184-192 pubmed

blue P Bertin, E Terao, EH Lee, P Lejeune, C Colson, A Danchin, E Collatz
The H-NS protein is involved in the biogenesis of flagella in Escherichia coli
J Bacteriol (1994) 176: 5537-5540 pubmed

blue JR Landgraf, M Levinthal, A Danchin
The role of H-NS in one carbon metabolism
Biochimie (1994) 76: 1063-1070 pubmed

blue M Levinthal, P Lejeune, A Danchin
The H-NS protein modulates the activation of the ilvIH operon of Escherichia coli K12 by Lrp, the leucine regulatory protein
Mol Gen Genet (1994) 242: 736-743 pubmed

blue A Danchin, E Krin
Filling the gap between hns and adhE in Escherichia coli K12
Microbiology (1995) 141 ( Pt 4): 959-960 pubmed

blue C Laurent-Winter, P Lejeune, A Danchin
The Escherichia coli DNA-binding protein H-NS is one of the first proteins to be synthesized after a nutritional upshift
Res Microbiol (1995) 146: 5-16 pubmed

blue C Laurent-Winter, S Ngo, A Danchin, P Bertin
Role of Escherichia coli histone-like nucleoid-structuring protein in bacterial metabolism and stress response--identification of targets by two-dimensional electrophoresis
Eur J Biochem (1997) 244: 767-773 pubmed

blue P Bertin, N Benhabiles, E Krin, C Laurent-Winter, C Tendeng, E Turlin, A Thomas, A Danchin, R Brasseur
The structural and functional organization of H-NS-like proteins is evolutionarily conserved in gram-negative bacteria
Mol Microbiol (1999) 31: 319-329 pubmed

blue O Soutourina, A Kolb, E Krin, C Laurent-Winter, S Rimsky, A Danchin, P Bertin
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: 7500-7508 pubmed j_bact

blue C Tendeng, C Badaut, E Krin, P Gounon, S Ngo, A Danchin, S Rimsky, P Bertin
Isolation and characterization of vicH, encoding a new pleiotropic regulator in Vibrio cholerae
J Bacteriol (2000) 182: 2026-2032 pubmed j_bact

blue P Bertin, F Hommais, E Krin, O Soutourina, C Tendeng, S Derzelle, A Danchin
H-NS and H-NS-like proteins in Gram-negative bacteria and their multiple role in the regulation of bacterial metabolism
Biochimie (2001) 83: 235-241  pdf

blue F Hommais, E Krin, C Laurent-Winter, O Soutourina, A Malpertuy, JP Le Caer, A Danchin, P Bertin
Large-scale monitoring of pleiotropic regulation of gene expression by the prokaryotic nucleoid-associated protein, H-NS
Mol Microbiol (2001) 40: 20-36  pdf

blueF Hommais, C Laurent-Winter, V Labas, E Krin, C Tendeng, O Soutourina, A Danchin, P Bertin
Effect of mild acid pH on the functioning of bacterial membranes in Vibrio cholerae
Proteomics (2002) 2: 571-579  pdf

blueOA Soutourina, E Krin, C Laurent-Winter, F Hommais, A Danchin, PN Bertin
Regulation of bacterial motility in response to low pH in Escherichia coli: the role of H-NS protein
Microbiology (2002) 148: 1543-1551  pdf

blueC Tendeng, OA Soutourina, A Danchin, PN Bertin
MvaT proteins in Pseudomonas spp.: a novel class of H-NS-like proteins
Microbiology (2003) 149: 3047-3050  pdf

blueC Tendeng, E Krin, OA Soutourina, A Marin, A Danchin, PN Bertin
A Novel H-NS-like protein from an antarctic psychrophilic bacterium reveals a crucial role for the N-terminal domain in thermal stability
J Biol Chem (2003) 278: 18754-18760  JBC

blueF Hommais, E Krin, JY Coppée, C Lacroix, E Yeramian, A Danchin, P Bertin
GadE (YhiE): a novel activator involved in the response to acid environment in Escherichia coli
Microbiology (2004) 150: 61-72  pdf

blueC Médigue, E Krin, G Pascal, V Barbe, A Bernsel, PN Bertin, F Cheung, S Cruveiller, S D'Amico, A Duilio, G Fang, G Feller, C Ho, S Mangenot, G Marino, J Nilsson, E Parrilli, EPC Rocha, Z Rouy, A Sekowska, ML Tutino, D Vallenet, G von Heijne, A Danchin
Coping with cold: the genome of the versatile marine Antarctica bacterium Pseudoalteromonas haloplanktis TAC125
Genome Res (2005) 15: 1325-1335 GR biosapiens b7

blueE Krin, S Derzelle, K Bedard, M Adib-Conquy, E Turlin, P Lenormand, M-F Hullo, I Bonne, N Chakroun, C Lacroix, A Danchin
Regulatory role of UvrY in adaptation of Photorhabdus luminescens growth inside the insect
Environmental Microbiology (2008) 10: 1118–1134 pubmed

blueY Jin, RM Watt, A Danchin, JD Huang
Small noncoding RNA GcvB is a novel regulator of acid resistance in Escherichia coli
BMC Genomics (2009) 10: 165  BMC