1. Evolutionary Biology
  2. Microbiology and Infectious Disease
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Symbiont location, host fitness, and possible coadaptation in a symbiosis between social amoebae and bacteria

  1. Longfei Shu
  2. Debra A Brock
  3. Katherine S Geist
  4. Jacob W Miller
  5. David C Queller
  6. Joan E Strassmann  Is a corresponding author
  7. Susanne DiSalvo  Is a corresponding author
  1. Washington University in St Louis, United States
  2. Southern Illinois University Edwardsville, United States
Research Article
  • Cited 16
  • Views 1,686
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Cite this article as: eLife 2018;7:e42660 doi: 10.7554/eLife.42660

Abstract

Recent symbioses, particularly facultative ones, are well suited for unravelling the evolutionary give and take between partners. Here we look at variation in natural isolates of the social amoeba Dictyostelium discoideum and their relationships with bacterial symbionts, Burkholderia hayleyella and Burkholderia agricolaris. Only about a third of field-collected amoebae carry a symbiont. We cured and cross-infected amoebae hosts with different symbiont association histories and then compared host responses to each symbiont type. Before curing, field-collected clones did not vary significantly in overall fitness, but infected hosts produced morphologically different multicellular structures. After curing and reinfecting, host fitness declined. However, natural B. hayleyella hosts suffered fewer fitness costs when reinfected with B. hayleyella, indicating that they have evolved mechanisms to tolerate their symbiont. Our work suggests that amoebae hosts have evolved mechanisms to tolerate specific acquired symbionts; exploring host-symbiont relationships that vary within species may provide further insights into disease dynamics.

Data availability

All raw data has been archived in the Washington University Library: https://doi.org/10.7936/wgnk-2c37

The following data sets were generated

Article and author information

Author details

  1. Longfei Shu

    Department of Biology, Washington University in St Louis, St Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Debra A Brock

    Department of Biology, Washington University in St Louis, St Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Katherine S Geist

    Department of Biology, Washington University in St Louis, St Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Jacob W Miller

    Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. David C Queller

    Department of Biology, Washington University in St Louis, St Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Joan E Strassmann

    Department of Biology, Washington University in St Louis, St Louis, United States
    For correspondence
    strassmann@wustl.edu
    Competing interests
    The authors declare that no competing interests exist.
  7. Susanne DiSalvo

    Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, United States
    For correspondence
    sdisalv@siue.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4001-4672

Funding

National Science Foundation (DEB1146375)

  • David C Queller
  • Joan E Strassmann

The Life Sciences Research Foundation

  • Longfei Shu

John Templeton Foundation (43667)

  • David C Queller
  • Joan E Strassmann

National Science Foundation (IOS1256416)

  • David C Queller

National Science Foundation (IOS1656756)

  • David C Queller

Simons Foundation

  • Longfei Shu

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

Reviewing Editor

  1. Tony Ruzzini, University of Saskatchewan, Canada

Publication history

  1. Received: October 8, 2018
  2. Accepted: December 30, 2018
  3. Accepted Manuscript published: December 31, 2018 (version 1)
  4. Version of Record published: January 17, 2019 (version 2)

Copyright

© 2018, Shu 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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