title: Membrane vesicles traffic signals and facilitate group activities in a prokaryote.
abstract: Many bacteria use extracellular signals to communicate and coordinate social activities, a process referred to as quorum sensing. Many quorum signals have significant hydrophobic character, and how these signals are trafficked between bacteria within a population is not understood. Here we show that the opportunistic human pathogen Pseudomonas aeruginosa packages the signalling molecule 2-heptyl-3-hydroxy-4-quinolone (pseudomonas quinolone signal; PQS) into membrane vesicles that serve to traffic this molecule within a population. Removal of these vesicles from the bacterial population halts cell-cell communication and inhibits PQS-controlled group behaviour. We also show that PQS actively mediates its own packaging and the packaging of other antimicrobial quinolines produced by P. aeruginosa into vesicles. These findings illustrate that a prokaryote possesses a signal trafficking system with features common to those used by higher organisms and outlines a novel mechanism for delivery of a signal critical for coordinating group behaviour in P. aeruginosa.
authors.affiliation: Department of Periodontics, The University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, USA.
authors.forename: Lauren M
authors.initials: LM
authors.lastname: Mashburn
authors.forename: Marvin
authors.initials: M
authors.lastname: Whiteley
mesh_terms: D001692:Biological Transport; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D011550:Pseudomonas aeruginosa / Q000166:cytology* / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D015363:Quinolones / Q000032:analysis / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D022142:Secretory Vesicles / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects
chemical_list: C407944:2-heptyl-3-hydroxy-4-quinolone; D015363:Quinolones