title: Specificity and complexity in bacterial quorum-sensing systems.
abstract: Quorum sensing (QS) is a microbial cell-to-cell communication process that relies on the production and detection of chemical signals called autoinducers (AIs) to monitor cell density and species complexity in the population. QS allows bacteria to behave as a cohesive group and coordinate collective behaviors. While most QS receptors display high specificity to their AI ligands, others are quite promiscuous in signal detection. How do specific QS receptors respond to their cognate signals with high fidelity? Why do some receptors maintain low signal recognition specificity? In addition, many QS systems are composed of multiple intersecting signaling pathways: what are the benefits of preserving such a complex signaling network when a simple linear 'one-to-one' regulatory pathway seems sufficient to monitor cell density? Here, we will discuss different molecular mechanisms employed by various QS systems that ensure productive and specific QS responses. Moreover, the network architectures of some well-characterized QS circuits will be reviewed to understand how the wiring of different regulatory components achieves different biological goals.
authors.affiliation: Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA 02111, USA.
authors.forename: Lisa A
authors.initials: LA
authors.lastname: Hawver
authors.affiliation: Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA 02111, USA Program in Molecular Microbiology, Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, MA 02111, USA.
authors.forename: Sarah A
authors.initials: SA
authors.lastname: Jung
authors.affiliation: Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA 02111, USA Program in Molecular Microbiology, Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, MA 02111, USA Wai-Leung.Ng@tufts.edu.
authors.forename: Wai-Leung
authors.initials: WL
authors.lastname: Ng
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D018407:Bacterial Physiological Phenomena; D015964:Gene Expression Regulation, Bacterial; D053038:Quorum Sensing / Q000502:physiology*; D012097:Repressor Proteins / Q000378:metabolism*; D015398:Signal Transduction; D015534:Trans-Activators / Q000378:metabolism*
chemical_list: D012097:Repressor Proteins; D015534:Trans-Activators; C064778:LuxR autoinducer binding proteins
keywords: chemical signaling; gene expression; group behavior; intercellular communication; regulatory network