Dynamic metabolic exchange governs a marine algal-bacterial interaction

  1. Einat Segev  Is a corresponding author
  2. Thomas P Wyche
  3. Ki Hyun Kim
  4. Jörn Petersen
  5. Claire Ellebrandt
  6. Hera Vlamakis
  7. Natasha Barteneva
  8. Joseph N Paulson
  9. Liraz Chai
  10. Jon Clardy
  11. Roberto Kolter  Is a corresponding author
  1. Harvard Medical School, United States
  2. Sungkyunkwan University, United States
  3. Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH, Germany
  4. Broad Institute, United States
  5. Dana-Farber Cancer Institute, United States
  6. The Hebrew University of Jerusalem, Israel

Abstract

Emiliania huxleyi is a model coccolithophore micro-alga that generates vast blooms in the ocean. Bacteria are not considered among the major factors influencing coccolithophore physiology. Here we show through a laboratory model system that the bacterium Phaeobacter inhibens, a well-studied member of the Roseobacter group, intimately interacts with E. huxleyi. While attached to the algal cell, bacteria initially promote algal growth but ultimately kill their algal host. Both algal growth enhancement and algal death are driven by the bacterially-produced phytohormone indole-3-acetic acid. Bacterial production of indole-3-acetic acid and attachment to algae are significantly increased by tryptophan, which is exuded from the algal cell. Algal death triggered by bacteria involves activation of pathways unique to oxidative stress response and programmed cell death. Our observations suggest that bacteria greatly influence the physiology and metabolism of E. huxleyi. Coccolithophore-bacteria interactions should be further studied in the environment to determine whether they impact micro-algal population dynamics on a global scale.

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Author details

  1. Einat Segev

    Department of Microbiology and Immunobiology, Harvard Medical School, Boston, United States
    For correspondence
    Einat_Segev@hms.harvard.edu
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2266-1219
  2. Thomas P Wyche

    Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, United States
    Competing interests
    No competing interests declared.
  3. Ki Hyun Kim

    School of Pharmacy, Sungkyunkwan University, Boston, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5285-9138
  4. Jörn Petersen

    Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH, Braunschweig, Germany
    Competing interests
    No competing interests declared.
  5. Claire Ellebrandt

    Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH, Braunschweig, Germany
    Competing interests
    No competing interests declared.
  6. Hera Vlamakis

    Broad Institute, Boston, United States
    Competing interests
    No competing interests declared.
  7. Natasha Barteneva

    Program in Cellular and Molecular Medicine, Boston Children's Hospital, Harvard Medical School, Boston, United States
    Competing interests
    No competing interests declared.
  8. Joseph N Paulson

    Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, Boston, United States
    Competing interests
    No competing interests declared.
  9. Liraz Chai

    Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel
    Competing interests
    No competing interests declared.
  10. Jon Clardy

    Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, United States
    Competing interests
    Jon Clardy, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0213-8356
  11. Roberto Kolter

    Department of Microbiology and Immunobiology, Harvard Medical School, Boston, United States
    For correspondence
    roberto_kolter@hms.harvard.edu
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9548-1481

Funding

European Molecular Biology Organization (LTF 649-2012)

  • Einat Segev

Human Frontier Science Program (LT000061/2013-L)

  • Einat Segev

DFG Transregio TRR-51 Roseobacter

  • Jörn Petersen

PCMM

  • Natasha Barteneva

National Institutes of Health (RR023459)

  • Natasha Barteneva

National Institutes of Health (GM086258)

  • Jon Clardy

National Institutes of Health (GM58213)

  • Roberto Kolter

National Institutes of Health (GM82137)

  • Roberto Kolter

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

Copyright

© 2016, Segev 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. Einat Segev
  2. Thomas P Wyche
  3. Ki Hyun Kim
  4. Jörn Petersen
  5. Claire Ellebrandt
  6. Hera Vlamakis
  7. Natasha Barteneva
  8. Joseph N Paulson
  9. Liraz Chai
  10. Jon Clardy
  11. Roberto Kolter
(2016)
Dynamic metabolic exchange governs a marine algal-bacterial interaction
eLife 5:e17473.
https://doi.org/10.7554/eLife.17473

Share this article

https://doi.org/10.7554/eLife.17473

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