Predictable properties of fitness landscapes induced by adaptational tradeoffs

  1. Suman G Das  Is a corresponding author
  2. Susana OL Direito
  3. Bartek Waclaw
  4. Rosalind J Allen
  5. Joachim Krug  Is a corresponding author
  1. University of Cologne, Germany
  2. University of Edinburgh, United Kingdom

Abstract

Fitness effects of mutations depend on environmental parameters. For example, mutations that increase fitness of bacteria at high antibiotic concentration often decrease fitness in the absence of antibiotic, exemplifying a tradeoff between adaptation to environmental extremes. We develop a mathematical model for fitness landscapes generated by such tradeoffs, based on experiments that determine the antibiotic dose-response curves of Escherichia coli strains, and previous observations on antibiotic resistance mutations. Our model generates a succession of landscapes with predictable properties as antibiotic concentration is varied. The landscape is nearly smooth at low and high concentrations, but the tradeoff induces a high ruggedness at intermediate antibiotic concentrations. Despite this high ruggedness, however, all the fitness maxima in the landscapes are evolutionarily accessible from the wild type. This implies that selection for antibiotic resistance in multiple mutational steps is relatively facile despite the complexity of the underlying landscape.

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Experimental data have been deposited in Edinburgh DataShare

The following data sets were generated
The following previously published data sets were used

Article and author information

Author details

  1. Suman G Das

    Institute for Biological Physics, University of Cologne, Koeln, Germany
    For correspondence
    sdas3@uni-koeln.de
    Competing interests
    The authors declare that no competing interests exist.
  2. Susana OL Direito

    School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Bartek Waclaw

    School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Rosalind J Allen

    School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Joachim Krug

    Department of Physics, University of Cologne, Cologne, Germany
    For correspondence
    jkrug@uni-koeln.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2143-6490

Funding

Deutsche Forschungsgemeinschaft (CRC 1310)

  • Joachim Krug

H2020 European Research Council (ERC Consolidator Grant 682237 EVOSTRUC)

  • Rosalind J Allen

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

Reviewing Editor

  1. Richard A Neher, University of Basel, Switzerland

Publication history

  1. Received: January 14, 2020
  2. Accepted: May 5, 2020
  3. Accepted Manuscript published: May 19, 2020 (version 1)
  4. Version of Record published: June 16, 2020 (version 2)

Copyright

© 2020, Das 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. Suman G Das
  2. Susana OL Direito
  3. Bartek Waclaw
  4. Rosalind J Allen
  5. Joachim Krug
(2020)
Predictable properties of fitness landscapes induced by adaptational tradeoffs
eLife 9:e55155.
https://doi.org/10.7554/eLife.55155

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