title: Inhibition of quorum sensing in Pseudomonas aeruginosa biofilm bacteria by a halogenated furanone compound.
abstract: Novel molecular tools have been constructed which allow for in situ detection of N-acyl homoserine lactone (AHL)-mediated quorum sensing in Pseudomonas aeruginosa biofilms. The reporter responds to AHL activation of LasR by expression of an unstable version of the green-fluorescent protein (Gfp). Gfp-based reporter technology has been applied for non-destructive, single-cell-level detection of quorum sensing in laboratory-based P. aeruginosa biofilms. It is reported that a synthetic halogenated furanone compound, which is a derivative of the secondary metabolites produced by the Australian macroalga Delisea pulchra, is capable of interfering with AHL-mediated quorum sensing in P. aeruginosa. It is demonstrated that the furanone compound specifically represses expression of a PlasB-gfp reporter fusion without affecting growth or protein synthesis. In addition, it reduces the production of important virulence factors, indicating a general effect on target genes of the las quorum sensing circuit. The furanone was applied to P. aeruginosa biofilms established in biofilm flow chambers. The Gfp-based analysis reveals that the compound penetrates microcolonies and blocks cell signalling and quorum sensing in most biofilm cells. The compound did not affect initial attachment to the abiotic substratum. It does, however, affect the architecture of the biofilm and enhances the process of bacterial detachment, leading to a loss of bacterial biomass from the substratum.
authors.affiliation: Department of Molecular Microbiology, BioCentrum-DTU, Technical University of Denmark, DK-2800 Lyngby, Denmark1.
authors.forename: Morten
authors.initials: M
authors.lastname: Hentzer
authors.affiliation: Lehrstuhl für Mikrobiologie, Technische Universität München, D-85350 Freising, Germany2.
authors.forename: Kathrin
authors.initials: K
authors.lastname: Riedel
authors.affiliation: Department of Molecular Microbiology, BioCentrum-DTU, Technical University of Denmark, DK-2800 Lyngby, Denmark1.
authors.forename: Thomas B
authors.initials: TB
authors.lastname: Rasmussen
authors.affiliation: Department of Molecular Microbiology, BioCentrum-DTU, Technical University of Denmark, DK-2800 Lyngby, Denmark1.
authors.forename: Arne
authors.initials: A
authors.lastname: Heydorn
authors.affiliation: Department of Molecular Microbiology, BioCentrum-DTU, Technical University of Denmark, DK-2800 Lyngby, Denmark1.
authors.forename: Jens Bo
authors.initials: JB
authors.lastname: Andersen
authors.affiliation: Department of Civil Engineering, Technological Institute, North Western University, Evanston, IL 60208-3109, USA3.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Parsek
authors.affiliation: School of Microbiology and Immunology, University of New South Wales (UNSW), Australia 20524.
authors.forename: Scott A
authors.initials: SA
authors.lastname: Rice
authors.affiliation: Lehrstuhl für Mikrobiologie, Technische Universität München, D-85350 Freising, Germany2.
authors.forename: Leo
authors.initials: L
authors.lastname: Eberl
authors.affiliation: Department of Molecular Microbiology, BioCentrum-DTU, Technical University of Denmark, DK-2800 Lyngby, Denmark1.
authors.forename: Søren
authors.initials: S
authors.lastname: Molin
authors.affiliation: Department of Clinical Microbiology, University Hospital (Rigshospitalet), DK-2100 Copenhagen, Denmark5.
authors.forename: Niels
authors.initials: N
authors.lastname: Høiby
authors.affiliation: School of Microbiology and Immunology, University of New South Wales (UNSW), Australia 20524.
authors.forename: Staffan
authors.initials: S
authors.lastname: Kjelleberg
authors.affiliation: Department of Molecular Microbiology, BioCentrum-DTU, Technical University of Denmark, DK-2800 Lyngby, Denmark1.
authors.forename: Michael
authors.initials: M
authors.lastname: Givskov
mesh_terms: D015107:4-Butyrolactone / Q000031:analogs & derivatives* / Q000378:metabolism; D001426:Bacterial Proteins; D018441:Biofilms / Q000187:drug effects* / Q000254:growth & development; D005663:Furans / Q000737:chemistry / Q000494:pharmacology*; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects*; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008666:Metalloendopeptidases / Q000235:genetics / Q000378:metabolism; D018613:Microscopy, Confocal; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects*
chemical_list: D001426:Bacterial Proteins; D005663:Furans; D008164:Luminescent Proteins; D011993:Recombinant Fusion Proteins; C088386:homoserine lactone; D049452:Green Fluorescent Proteins; D008666:Metalloendopeptidases; C043859:pseudolysin, Pseudomonas aeruginosa; D015107:4-Butyrolactone