Open AccessColonial architecture in mixed species assemblages affects AHL mediated gene expression
Author(s) -
Mason Vince P.,
Markx Gerard H.,
Thompson Ian P.,
Andrews Joanna S.,
Manefield Mike
Publication year - 2005
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1016/j.femsle.2005.01.031
Subject(s) - quorum sensing , extracellular , autoinducer , gene expression , biology , escherichia coli , gene , regulation of gene expression , homoserine , bacteria , microbiology and biotechnology , genetics , virulence
Many bacterial species produce metabolites that accumulate in the extracellular environment and induce specific transcriptional responses in producing cells. This phenomenon, most often referred to as quorum sensing, is thought to constitute a self‐cell‐density sensing mechanism allowing bacterial populations to alter gene expression in response to increases in their own density. Quorum sensing systems involving N ‐acyl‐ l ‐homoserine lactone (AHL) production and response are the most intensively investigated example. In this study we have employed a novel technique, known as dielectrophoresis, to investigate the impact of colonial architecture on the induction of AHL mediated gene expression. Using dielectrophoresis, we constructed artificial mixed species microcolonies with specific architectures. In this way, we were able to show that approximately 1000 Escherichia coli cells layered over an immobilised cluster of approximately 500 AHL responsive cells alters the response of this cluster to AHLs supplied either exogenously or endogenously. These findings lend credence to the hypothesis that the accumulation of extracellular metabolites signifies generic crowding in mixed species assemblages.