title: Information processing and signal integration in bacterial quorum sensing.
abstract: Bacteria communicate using secreted chemical signaling molecules called autoinducers in a process known as quorum sensing. The quorum-sensing network of the marine bacterium Vibrio harveyi uses three autoinducers, each known to encode distinct ecological information. Yet how cells integrate and interpret the information contained within these three autoinducer signals remains a mystery. Here, we develop a new framework for analyzing signal integration on the basis of information theory and use it to analyze quorum sensing in V. harveyi. We quantify how much the cells can learn about individual autoinducers and explain the experimentally observed input-output relation of the V. harveyi quorum-sensing circuit. Our results suggest that the need to limit interference between input signals places strong constraints on the architecture of bacterial signal-integration networks, and that bacteria probably have evolved active strategies for minimizing this interference. Here, we analyze two such strategies: manipulation of autoinducer production and feedback on receptor number ratios.
authors.affiliation: Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, Princeton, NJ 08540, USA. pmehta@princeton.edu
authors.forename: Pankaj
authors.initials: P
authors.lastname: Mehta
authors.forename: Sidhartha
authors.initials: S
authors.lastname: Goyal
authors.forename: Tao
authors.initials: T
authors.lastname: Long
authors.forename: Bonnie L
authors.initials: BL
authors.lastname: Bassler
authors.forename: Ned S
authors.initials: NS
authors.lastname: Wingreen
mesh_terms: D025461:Feedback, Physiological; D007257:Information Theory; D011494:Protein Kinases / Q000378:metabolism; D053038:Quorum Sensing; D011956:Receptors, Cell Surface / Q000378:metabolism; D015398:Signal Transduction; D014733:Vibrio / Q000201:enzymology / Q000378:metabolism*
chemical_list: D011956:Receptors, Cell Surface; D011494:Protein Kinases