Aggregation of Vibrio cholerae by Cationic Polymers Enhances Quorum Sensing but Overrides Biofilm Dissipation in Response to Autoinduction

Research output: Contribution to journalArticle

Authors

Colleges, School and Institutes

External organisations

  • University of Texas Medical School at Houston

Abstract

Vibrio cholerae is a Gram-negative bacterium found in aquatic environments and a human pathogen of global significance. Its transition between host-associated and environmental lifestyles involves the tight regulation of niche-specific phenotypes such as motility, biofilm formation, and virulence. V. cholerae's transition from the host to environmental dispersal usually involves suppression of virulence and dispersion of biofilm communities. In contrast to this naturally occurring transition, bacterial aggregation by cationic polymers triggers a unique response, which is to suppress virulence gene expression while also triggering biofilm formation by V. cholerae, an artificial combination of traits that is potentially very useful to bind and neutralize the pathogen from contaminated water. Here, we set out to uncover the mechanistic basis of this polymer-triggered bacterial behavior. We found that bacteria-polymer aggregates undergo rapid autoinduction and achieve quorum sensing at bacterial densities far below those required for autoinduction in the absence of polymers. We demonstrate this induction of quorum sensing is due both to a rapid formation of autoinducer gradients and local enhancement of autoinducer concentrations within bacterial clusters as well as the stimulation of CAI-1 and AI-2 production by aggregated bacteria. We further found that polymers cause an induction of the biofilm-specific regulator VpsR and the biofilm structural protein RbmA, bypassing the usual suppression of biofilm during autoinduction. Overall, this study highlights that synthetic materials can be used to cross-wire natural bacterial responses to achieve a combination of phenotypes with potentially useful applications.

Details

Original languageEnglish
Pages (from-to)3021–3029
JournalACS chemical biology
Volume13
Issue number10
Early online date11 Sep 2018
Publication statusPublished - 19 Oct 2018

ASJC Scopus subject areas