title: Modeling bacterial quorum sensing in open and closed environments: potential discrepancies between agar plate and culture flask experiments.
abstract: Quorum sensing (QS) is a process of bacterial communication and cooperation mediated by the release of jointly exploited signals and "public goods" into the environment. There are conflicting reports on the behavior of mutants deficient in the release of these materials. Namely, mutants that appear perfectly viable and capable of outgrowing wild type cells in a closed model system such as a culture flask, may not be viable or invasive on open surfaces such as agar plates. Here we show via agent-based computational simulations that this apparent discrepancy is due to the difference between open and closed systems. We suggest that the experimental difference is due to the fact that wild type cells can easily saturate a well-mixed culture flask with signals and public goods so QS will be not necessary after a certain time point. As a consequence, QS-deficient mutants can continue to grow even after the wild type population has vanished. This phenomenon is not likely to occur in open environments including open surfaces and agar plate models. In other words, even if QS is required for survival, QS deficient mutants may grow faster initially in short term laboratory experiments or computer simulations, while only WT cells appear stable over longer time scales, especially when adaptation to changing environments is important.
authors.affiliation: Pázmány Péter Catholic University, 1083, Budapest, Hungary.
authors.forename: Dóra
authors.initials: D
authors.lastname: Bihary
authors.forename: Marietta
authors.initials: M
authors.lastname: Tóth
authors.forename: Ádám
authors.initials: Á
authors.lastname: Kerényi
authors.forename: Vittorio
authors.initials: V
authors.lastname: Venturi
authors.forename: Sándor
authors.initials: S
authors.lastname: Pongor
mesh_terms: D000362:Agar / Q000737:chemistry*; D001426:Bacterial Proteins / Q000235:genetics; D001431:Bacteriological Techniques; D003198:Computer Simulation; D005838:Genotype; D050296:Microbial Viability; D008954:Models, Biological; D009154:Mutation; D010641:Phenotype; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000254:growth & development*; D053038:Quorum Sensing; D012097:Repressor Proteins / Q000235:genetics; D013997:Time Factors; D015534:Trans-Activators / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D012097:Repressor Proteins; D015534:Trans-Activators; C064778:LuxR autoinducer binding proteins; D000362:Agar