Abstract

Bacterial chemotaxis systems are as diverse as the environments that bacteria inhabit, but how much environmental variation can cells tolerate with a single system? Diversification of a single chemotaxis system could serve as an alternative, or even evolutionary stepping-stone, to switching between multiple systems. We hypothesized that mutations in gene regulation could lead to heritable control of chemotactic diversity. By simulating foraging and colonization of Escherichia coli using a single-cell chemotaxis model, we found that different environments selected for different behaviors. The resulting trade-offs show that populations facing diverse environments would ideally diversify behaviors when time for navigation is limited. We show that advantageous diversity can arise from changes in the distribution of protein levels among individuals, which could occur through mutations in gene regulation. We propose experiments to test our prediction that chemotactic diversity in a clonal population could be a selectable trait that enables adaptation to environmental variability.

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Author details

  1. Nicholas W Frankel

    Yale University, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. William Pontius

    Yale University, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Yann S Dufour

    Yale University, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Junjiajia Long

    Yale University, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Luis Hernandez-Nunez

    Yale University, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Thierry Emonet

    Yale University, New Haven, United States
    For correspondence
    thierry.emonet@yale.edu
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2014, Frankel 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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  1. Nicholas W Frankel
  2. William Pontius
  3. Yann S Dufour
  4. Junjiajia Long
  5. Luis Hernandez-Nunez
  6. Thierry Emonet
(2014)
Adaptability of non-genetic diversity in bacterial chemotaxis
eLife 3:e03526.
https://doi.org/10.7554/eLife.03526

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https://doi.org/10.7554/eLife.03526

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