Combinatorial quorum sensing allows bacteria to resolve their social and physical environment

Cornforth, Daniel M. and Popat, Roman and McNally, Luke and Gurney, James and Scott-Phillips, Thomas C. and Ivens, Alasdair and Diggle, Stephen P. and Brown, Sam P. (2014) Combinatorial quorum sensing allows bacteria to resolve their social and physical environment. Proceedings of the National Academy of Sciences, 111 (11). pp. 4280-4284. ISSN 1091-6490

PDF - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Download (1MB) | Preview


Quorum sensing (QS) is a cell–cell communication system that controls gene expression in many bacterial species, mediated by diffusible signal molecules. Although the intracellular regulatory mechanisms of QS are often well-understood, the functional roles of QS remain controversial. In particular, the use of multiple signals by many bacterial species poses a serious challenge to current functional theories. Here, we address this challenge by showing that bacteria can use multiple QS signals to infer both their social (density) and physical (mass-transfer) environment. Analytical and evolutionary simulation models show that the detection of, and response to, complex social/physical contrasts requires multiple signals with distinct half-lives and combinatorial (nonadditive) responses to signal concentrations. We test these predictions using the opportunistic pathogen Pseudomonas aeruginosa and demonstrate significant differences in signal decay betweeallyn its two primary signal molecules, as well as diverse combinatorial responses to dual-signal inputs. QS is associated with the control of secreted factors, and we show that secretome genes are preferentially controlled by synergistic “AND-gate” responses to multiple signal inputs, ensuring the effective expression of secreted factors in high-density and low mass-transfer environments. Our results support a new functional hypothesis for the use of multiple signals and, more generally, show that bacteria are capable of combinatorial communication.

Item Type: Article
Keywords: Diffusion Sensing, Bacterial Signaling, Efficiency Sensing, Collective Behavior, Bacterial Cooperation
Schools/Departments: University of Nottingham UK Campus > Faculty of Medicine and Health Sciences > School of Life Sciences
Identification Number:
Depositing User: Diggle, Dr Stephen
Date Deposited: 23 Aug 2016 08:31
Last Modified: 14 Sep 2016 20:43

Actions (Archive Staff Only)

Edit View Edit View