title: Modeling quorum sensing trade-offs between bacterial cell density and system extension from open boundaries.
abstract: Bacterial communities undergo collective behavioural switches upon producing and sensing diffusible signal molecules; a mechanism referred to as Quorum Sensing (QS). Exemplarily, biofilm organic matrices are built concertedly by bacteria in several environments. QS scope in bacterial ecology has been debated for over 20 years. Different perspectives counterpose the role of density reporter for populations to that of local environment diffusivity probe for individual cells. Here we devise a model system where tubes of different heights contain matrix-embedded producers and sensors. These tubes allow non-limiting signal diffusion from one open end, thereby showing that population spatial extension away from an open boundary can be a main critical factor in QS. Experimental data, successfully recapitulated by a comprehensive mathematical model, demonstrate how tube height can overtake the role of producer density in triggering sensor activation. The biotic degradation of the signal is found to play a major role and to be species-specific and entirely feedback-independent.
authors.affiliation: SISSA, International School for Advanced studies, via Bonomea 265, 34136 Trieste, Italy.
authors.forename: Mattia
authors.initials: M
authors.lastname: Marenda
authors.affiliation: Department of Agronomy, Animals, Food, Natural resources and Environment DAFNAE, Università di Padova, Viale dell'Università 16, 35020 Legnaro (Padova) Italy.
authors.forename: Marina
authors.initials: M
authors.lastname: Zanardo
authors.affiliation: Department of Physics and Astronomy "Galileo Galilei" Università di Padova, Via Marzolo 8, 35131 Padova Italy.|INFN, National Institute for Nuclear Physics, Sezione di Padova, Via Marzolo 8, 35131 Padova, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Trovato
authors.affiliation: Department of Physics and Astronomy "Galileo Galilei" Università di Padova, Via Marzolo 8, 35131 Padova Italy.|CNISM, National Interuniversity Consortium for the Physical Sciences of Matter, Unità di Padova, Via Marzolo 8, 35131 Padova, Italy.
authors.forename: Flavio
authors.initials: F
authors.lastname: Seno
authors.affiliation: Department of Agronomy, Animals, Food, Natural resources and Environment DAFNAE, Università di Padova, Viale dell'Università 16, 35020 Legnaro (Padova) Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Squartini
mesh_terms: D001419:Bacteria / Q000254:growth & development*; D001431:Bacteriological Techniques / Q000379:methods*; D008954:Models, Biological; D053038:Quorum Sensing; D062206:Spatial Analysis