| Title: | Spatially propagating activation of quorum sensing in Vibrio fischeri and the transition to low population density |
| Author(s): | Patel K; Rodriguez C; Stabb EV; Hagen SJ; |
| Address: | "Physics Department, University of Florida, Gainesville, Florida 32611-8440, USA. Department of Microbiology, University of Georgia, Athens, Georgia 30602, USA. Department of Biological Sciences, University of Illinois, Chicago, Illinois 60607, USA" |
| DOI: | 10.1103/PhysRevE.101.062421 |
| ISSN/ISBN: | 2470-0053 (Electronic) 2470-0045 (Linking) |
| Abstract: | "Bacteria communicate by secreting and detecting diffusible small molecule signals or pheromones. Using the local concentrations of these signals to regulate gene expression, individual cells can synchronize changes in phenotype population-wide, a behavior known as quorum sensing (QS). In unstirred media, the interplay between diffusion of signals, bacterial growth, and regulatory feedback can generate complex spatial and temporal patterns of expression of QS-controlled genes. Here we identify the parameters that allow a local signal to trigger a self-sustaining, traveling activation of QS behavior. Using the natural bioluminescence of wild-type Vibrio fischeri as a readout of its lux QS system, we measure the induction of a spreading QS response by a localized triggering stimulus in unstirred media. Our data show that a QS response propagates outward, sustained by positive feedback in synthesis of the diffusible signal, and that this response occurs only if the triggering stimulus exceeds a critical threshold. We also test how the autonomous or untriggered activation of the V. fischeri QS pathway changes at very low initial population densities. At the lowest population densities, clusters of cells do not transition to a self-sensing behavior, but rather remain in communication via signal diffusion until they reach sufficiently large size that their own growth slows. Our data, which are reproduced by simple growth and diffusion simulations, indicate that in part owing to bacterial growth behavior, natural QS systems can be characterized by long distance communication through signal diffusion even in very heterogeneous and spatially dispersed populations" |
| Keywords: | "Aliivibrio fischeri/*cytology/growth & development Feedback, Physiological Luminescent Measurements Population Density *Quorum Sensing;" |
| Notes: | "MedlinePatel, Keval Rodriguez, Coralis Stabb, Eric V Hagen, Stephen J eng 2020/07/22 Phys Rev E. 2020 Jun; 101(6-1):062421. doi: 10.1103/PhysRevE.101.062421" |
