Spatial structure favors microbial coexistence except when slower mediator diffusion weakens interactions

  1. Alexander Lobanov
  2. Samantha Dyckman
  3. Helen Kurkjian
  4. Babak Momeni  Is a corresponding author
  1. Boston College, United States
  2. Swiss Federal Institute of Aquatic Science and Technology, Switzerland

Abstract

Microbes often exist in spatially structured environments and many of their interactions are mediated through diffusible metabolites. How does such a context affect microbial coexistence? To address this question, we use a model in which the spatial distributions of species and diffusible interaction mediators are explicitly included. We simulate the enrichment process, examining how microbial species spatially reorganize and how eventually a subset of them coexist. In our model we find that slower motility of cells promotes coexistence by allowing species to co-localize with their facilitators and avoid their inhibitors. We additionally find that a spatially structured environment is more influential when species mostly facilitate each other, rather than when they are mostly competing. More coexistence is observed when species produce many mediators and consume some (not many or few) mediators, and when overall consumption and production rates are balanced. Interestingly, coexistence appears to be disfavored when mediators are diffusing slowly because that leads to weaker interaction strengths. Overall, our results offer new insights into how production, consumption, motility, and diffusion intersect to determine microbial coexistence in a spatially structured environment.

Data availability

Codes used to generate the data in this study are shared on GitHub at https://github.com/bmomeni/spatial-coexistence.

Article and author information

Author details

  1. Alexander Lobanov

    Biology Department, Boston College, Chestnut Hill, United States
    Competing interests
    No competing interests declared.
  2. Samantha Dyckman

    Biology Department, Boston College, Chestnut Hill, United States
    Competing interests
    No competing interests declared.
  3. Helen Kurkjian

    Department of Aquatic Ecology, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
    Competing interests
    No competing interests declared.
  4. Babak Momeni

    Biology Department, Boston College, Chestnut Hill, United States
    For correspondence
    momeni@bc.edu
    Competing interests
    Babak Momeni, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1271-5196

Funding

Richard and Susan Smith Family Foundation

  • Samantha Dyckman
  • Helen Kurkjian
  • Babak Momeni

Boston College (URF)

  • Alexander Lobanov

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

Reviewing Editor

  1. Sara Mitri, University of Lausanne, Switzerland

Version history

  1. Preprint posted: August 1, 2022 (view preprint)
  2. Received: August 6, 2022
  3. Accepted: June 20, 2023
  4. Accepted Manuscript published: June 23, 2023 (version 1)
  5. Version of Record published: July 14, 2023 (version 2)

Copyright

© 2023, Lobanov 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. Alexander Lobanov
  2. Samantha Dyckman
  3. Helen Kurkjian
  4. Babak Momeni
(2023)
Spatial structure favors microbial coexistence except when slower mediator diffusion weakens interactions
eLife 12:e82504.
https://doi.org/10.7554/eLife.82504

Share this article

https://doi.org/10.7554/eLife.82504

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