title: Proteomic studies highlight outer-membrane proteins related to biofilm development in the marine bacterium Pseudoalteromonas sp. D41.
abstract: Bacterial biofilm development is conditioned by complex processes involving bacterial attachment to surfaces, growth, mobility, and exoproduct production. The marine bacterium Pseudoalteromonas sp. strain D41 is able to attach strongly onto a wide variety of substrates, which promotes subsequent biofilm development. Study of the outer-membrane and total soluble proteomes showed ten spots with significant intensity variations when this bacterium was grown in biofilm compared to planktonic cultures. MS/MS de novo sequencing analysis allowed the identification of four outer-membrane proteins of particular interest since they were strongly induced in biofilms. These proteins are homologous to a TonB-dependent receptor (TBDR), to the OmpW and OmpA porins, and to a type IV pilus biogenesis protein (PilF). Gene expression assays by quantitative RT-PCR showed that the four corresponding genes were upregulated during biofilm development on hydrophobic and hydrophilic surfaces. The Pseudomonas aeruginosa mutants unable to produce any of the OmpW, OmpA, and PilF homologues yielded biofilms with lower biovolumes and altered architectures, confirming the involvement of these proteins in the biofilm formation process. Our results indicate that Pseudoalteromonas sp. D41 shares biofilm formation mechanisms with human pathogenic bacteria, but also relies on TBDR, which might be more specific to the marine environment.
authors.affiliation: Laboratoire de Biotechnologie et Chimie Marines, Université de Bretagne-Sud (UEB), IUEM, Lorient, France.
authors.forename: Andrés
authors.initials: A
authors.lastname: Ritter
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Com
authors.forename: Alexis
authors.initials: A
authors.lastname: Bazire
authors.forename: Marina Dos Santos
authors.initials: Mdos S
authors.lastname: Goncalves
authors.forename: Ludovic
authors.initials: L
authors.lastname: Delage
authors.forename: Gaël
authors.initials: G
authors.lastname: Le Pennec
authors.forename: Charles
authors.initials: C
authors.lastname: Pineau
authors.forename: Catherine
authors.initials: C
authors.lastname: Dreanno
authors.forename: Chantal
authors.initials: C
authors.lastname: Compère
authors.forename: Alain
authors.initials: A
authors.lastname: Dufour
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D018441:Biofilms; D015180:Electrophoresis, Gel, Two-Dimensional; D010641:Phenotype; D020543:Proteome / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D040901:Proteomics; D031161:Pseudoalteromonas / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D012995:Solubility
chemical_list: D001425:Bacterial Outer Membrane Proteins; D020543:Proteome