Quantifying the integration of quorum-sensing signals with single-cell resolution. Author Tao Long, Kimberly Tu, Yufang Wang, Pankaj Mehta, N Ong, Bonnie Bassler, Ned Wingreen Publication Year 2009 Type Journal Article Abstract Cell-to-cell communication in bacteria is a process known as quorum sensing that relies on the production, detection, and response to the extracellular accumulation of signaling molecules called autoinducers. Often, bacteria use multiple autoinducers to obtain information about the vicinal cell density. However, how cells integrate and interpret the information contained within multiple autoinducers remains a mystery. Using single-cell fluorescence microscopy, we quantified the signaling responses to and analyzed the integration of multiple autoinducers by the model quorum-sensing bacterium Vibrio harveyi. Our results revealed that signals from two distinct autoinducers, AI-1 and AI-2, are combined strictly additively in a shared phosphorelay pathway, with each autoinducer contributing nearly equally to the total response. We found a coherent response across the population with little cell-to-cell variation, indicating that the entire population of cells can reliably distinguish several distinct conditions of external autoinducer concentration. We speculate that the use of multiple autoinducers allows a growing population of cells to synchronize gene expression during a series of distinct developmental stages. Keywords Gene Expression Regulation, Bacterial, Quorum Sensing, Vibrio, Bacterial Proteins, 4-Butyrolactone, Signal Transduction, Lactones, Microscopy, Fluorescence, Homoserine, Microscopy, Phase-Contrast Journal PLoS Biol Volume 7 Issue 3 Pages e68 Date Published 2009 Mar 24 ISSN Number 1545-7885 DOI 10.1371/journal.pbio.1000068 Alternate Journal PLoS Biol PMCID PMC2661960 PMID 19320539 PubMedPubMed CentralGoogle ScholarBibTeXEndNote X3 XML