Dynamic metabolic exchange governs a marine algal-bacterial interaction
- Harvard Medical School, United States
- Sungkyunkwan University, United States
- Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH, Germany
- Broad Institute, United States
- Dana-Farber Cancer Institute, United States
- 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.
Data availability
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Dynamic Metabolic Exchange Governs a Marine Algal-Bacterial InteractionPublicly available at the NCBI Sequence Read Archive (SRA accession: SRP075256).
Article and author information
Author details
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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Dynamic metabolic exchange governs a marine algal-bacterial interaction
eLife 5:e17473.
https://doi.org/10.7554/eLife.17473
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