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Title: Quorum sensing controls Vibrio cholerae multicellular aggregate formation
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.  more » « less
Award ID(s):
1713731 1734030
NSF-PAR ID:
10083040
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
eLife
Volume:
7
ISSN:
2050-084X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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