Single cell analysis of Vibrio harveyi uncovers functional heterogeneity in response to quorum sensing signals

BMC Microbiology

Research Article

Kirsten Jung¹  Claudia Anetzberger¹  Ursula Schell² 

[1] Munich Center for integrated Protein Science (CiPSM) at the Department of Biology I, Microbiology, Ludwig-Maximilians-Universität Munich, Großhaderner Str. 2-4, 82152, Martinsried, Germany;Munich Center for integrated Protein Science (CiPSM) at the Department of Biology I, Microbiology, Ludwig-Maximilians-Universität Munich, Großhaderner Str. 2-4, 82152, Martinsried, Germany;Max von Pettenkofer Institut, Ludwig-Maximilians-Universität Munich, Pettenkoferstr. 9a, 80336, Munich, Germany;

关键词: Bioluminescence;    Exoprotease;    Type III secretion;    Autoinducer;    Division of labor;    Subpopulation;   

DOI  :  10.1186/1471-2180-12-209

 received in 2012-07-20, accepted in 2012-09-13,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundVibrio harveyi and closely related species are important pathogens in aquaculture. A complex quorum sensing cascade involving three autoinducers controls bioluminescence and several genes encoding virulence factors. Single cell analysis of a V. harveyi population has already indicated intercellular heterogeneity in the production of bioluminescence. This study was undertaken to analyze the expression of various autoinducer-dependent genes in individual cells.ResultsHere we used reporter strains bearing promoter::gfp fusions to monitor the induction/repression of three autoinducer-regulated genes in wild type conjugates at the single cell level. Two genes involved in pathogenesis - vhp and vscP, which code for an exoprotease and a component of the type III secretion system, respectively, and luxC (the first gene in the lux operon) were chosen for analysis. The lux operon and the exoprotease gene are induced, while vscP is repressed at high cell density. As controls luxS and recA, whose expression is not dependent on autoinducers, were examined. The responses of the promoter::gfp fusions in individual cells from the same culture ranged from no to high induction. Importantly, simultaneous analysis of two autoinducer induced phenotypes, bioluminescence (light detection) and exoproteolytic activity (fluorescence of a promoter::gfp fusion), in single cells provided evidence for functional heterogeneity within a V. harveyi population.ConclusionsAutoinducers are not only an indicator for cell density, but play a pivotal role in the coordination of physiological activities within the population.

【 授权许可】

Unknown   
© Anetzberger et al.; licensee BioMed Central Ltd. 2012. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.