Quorum sensing controls Vibrio cholerae multicellular aggregate formation
Abstract
Bacteria communicate and collectively regulate gene expression using a process called quorum sensing (QS). QS relies on group-wide responses to signal molecules called autoinducers. Here, we show that QS activates a new program of multicellularity in Vibrio cholerae. This program, which we term aggregation, is distinct from the canonical surface-biofilm formation program, which QS represses. Aggregation is induced by autoinducers, occurs rapidly in cell suspensions, and does not require cell-division, features strikingly dissimilar from those characteristic of V. cholerae biofilm formation. Extracellular DNA limits aggregate size, but is not sufficient to drive aggregation. A mutagenesis screen identifies genes required for aggregate formation, revealing proteins involved in V. cholerae intestinal colonization, stress response, and a protein that distinguishes the current V. cholerae pandemic strain from earlier pandemic strains. We suggest that QS-controlled aggregate formation is important for V. cholerae to successfully transit between the marine niche and the human host.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files. Source data files have been provided for all quantitative data.
Article and author information
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Funding
Howard Hughes Medical Institute
- Bonnie L Bassler
National Institute of General Medical Sciences (R01GM082938)
- Ned S Wingreen
Alexander von Humboldt-Stiftung
- Bonnie L Bassler
National Science Foundation (MCB-1713731)
- Bonnie L Bassler
National Institute of General Medical Sciences (2R37GM065859)
- Bonnie L Bassler
National Science Foundation (PHY-1734030)
- Matthew Jemielita
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Jemielita et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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