Inverse regulation of Vibrio cholerae biofilm dispersal by polyamine signals

  1. Andrew A Bridges
  2. Bonnie L Bassler  Is a corresponding author
  1. Princeton University, United States

Abstract

The global pathogen Vibrio cholerae undergoes cycles of biofilm formation and dispersal in the environment and the human host. Little is understood about biofilm dispersal. Here, we show that MbaA, a periplasmic polyamine sensor, and PotD1, a polyamine importer, regulate V. cholerae biofilm dispersal. Spermidine, a commonly produced polyamine, drives V. cholerae dispersal, whereas norspermidine, an uncommon polyamine produced by vibrios, inhibits dispersal. Spermidine and norspermidine differ by one methylene group. Both polyamines control dispersal via MbaA detection in the periplasm and subsequent signal relay. Our results suggest that dispersal fails in the absence of PotD1 because endogenously produced norspermidine is not reimported, periplasmic norspermidine accumulates, and it stimulates MbaA signaling. These results suggest that V. cholerae uses MbaA to monitor environmental polyamines, blends of which potentially provide information about numbers of 'self' and 'other'. This information is used to dictate whether or not to disperse from biofilms.

Data availability

All data generated and analyzed in this study are included in the manuscript and supporting files. Source data files have been provided in Zenodo (https://doi.org/10.5281/zenodo.4651348).

Article and author information

Author details

  1. Andrew A Bridges

    Department of Molecular Biology, Princeton University, Princeton, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8132-751X
  2. Bonnie L Bassler

    Department of Molecular Biology, Princeton University, Princeton, United States
    For correspondence
    bbassler@princeton.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0043-746X

Funding

Howard Hughes Medical Institute (NA)

  • Bonnie L Bassler

National Institutes of Health (5R37GM065859)

  • Bonnie L Bassler

National Science Foundation (MCB-1713731)

  • Bonnie L Bassler

Alexander von Humboldt-Stiftung (NA)

  • Bonnie L Bassler

Damon Runyon Cancer Research Foundation (DRG-2302-17)

  • Andrew A Bridges

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Michael T Laub, Massachusetts Institute of Technology, United States

Version history

  1. Received: December 5, 2020
  2. Accepted: April 13, 2021
  3. Accepted Manuscript published: April 15, 2021 (version 1)
  4. Version of Record published: April 27, 2021 (version 2)

Copyright

© 2021, Bridges & Bassler

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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  1. Andrew A Bridges
  2. Bonnie L Bassler
(2021)
Inverse regulation of Vibrio cholerae biofilm dispersal by polyamine signals
eLife 10:e65487.
https://doi.org/10.7554/eLife.65487

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