title: A proteomic approach of SigX function in Pseudomonas aeruginosa outer membrane composition.
abstract: SigX is one of the 19 extracytoplasmic function sigma factors that have been predicted in the human opportunistic pathogen Pseudomonas aeruginosa genome. SigX is involved in the transcription of oprF, encoding the major outer membrane protein OprF, a pleiotropic porin that contributes to the maintaining of the wall structure, and is essential to P. aeruginosa virulence. This study aimed to get further insights into the functions of SigX. We performed here an outer membrane subproteome of a sigX mutant. Proteomic investigations revealed lower production of 8 porins among which 4 gated channels involved in iron or hem uptake, OprF, and the three substrate-specific proteins OprD, OprQ and OprE. On the other side, the glucose-specific porin OprB and the lipid A 3-O-deacylase that is involved in LPS modification were up-regulated. Our results indicate that SigX may be involved in the control and/or regulation of the outer membrane composition.
  
  
  CONCLUSIONS
  A proteomic approach was used herein to get further insights into SigX functions in P. aeruginosa. The data presented here suggest that SigX is involved in the outer membrane protein composition, and could be linked to a regulatory network involved in OM homeostasis.
authors: Laboratory of Microbiology Signal and Microenvironment (LMSM) EA 4312, University of Rouen, GRRs SeSa, IRIB, Evreux F-27000, France.
authors: Rachel
authors: R
authors: Duchesne
authors: Laboratory of Microbiology Signal and Microenvironment (LMSM) EA 4312, University of Rouen, GRRs SeSa, IRIB, Evreux F-27000, France.
authors: Emeline
authors: E
authors: Bouffartigues
authors: Laboratory of Microbiology Signal and Microenvironment (LMSM) EA 4312, University of Rouen, GRRs SeSa, IRIB, Evreux F-27000, France.
authors: Virginie
authors: V
authors: Oxaran
authors: Laboratory of Microbiology Signal and Microenvironment (LMSM) EA 4312, University of Rouen, GRRs SeSa, IRIB, Evreux F-27000, France.
authors: Olivier
authors: O
authors: Maillot
authors: Cell Imaging Platform of Normandy (PRIMACEN), IRIB, Faculty of Sciences, University of Rouen, Mont-Saint-Aignan F-76821, France.
authors: Magalie
authors: M
authors: Bénard
authors: Laboratory of Microbiology Signal and Microenvironment (LMSM) EA 4312, University of Rouen, GRRs SeSa, IRIB, Evreux F-27000, France.
authors: Marc G J
authors: MG
authors: Feuilloley
authors: Laboratory of Microbiology Signal and Microenvironment (LMSM) EA 4312, University of Rouen, GRRs SeSa, IRIB, Evreux F-27000, France.
authors: Nicole
authors: N
authors: Orange
authors: Laboratory of Microbiology Signal and Microenvironment (LMSM) EA 4312, University of Rouen, GRRs SeSa, IRIB, Evreux F-27000, France. Electronic address: chevalier@univ-rouen.fr.
authors: Sylvie
authors: S
authors: Chevalier
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000096:biosynthesis* / Q000235:genetics; D002462:Cell Membrane / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D009154:Mutation; D018272:Porins / Q000096:biosynthesis* / Q000235:genetics; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000378:metabolism*; D012808:Sigma Factor / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic / Q000502:physiology*
chemical_list: D001425:Bacterial Outer Membrane Proteins; D018272:Porins; D012808:Sigma Factor
keywords: ECF sigma factor SigX; Outer membrane proteome; Porins; Pseudomonas aeruginosa