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Updated: May 4, 2026
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Unraveling the Unseen Players in the Ocean - A Field Guide to Water Chemistry and Marine Microbiology
Published on: November 5, 2014
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Marine particle microbiomes during a spring diatom bloom contain active sulfate-reducing bacteria
Robin Siebers1, Doreen Schultz1, Mohamed S Farza1
1Institute of Microbiology, University of Greifswald, Greifswald, Germany.
FEMS Microbiology Ecology
|March 15, 2024
Summary
Marine phytoplankton blooms create anoxic niches within particles, supporting sulfate-reducing bacteria. This study reveals crucial algal-bacterial interactions and carbon cycling in shallow North Sea waters.
Area of Science:
- Marine microbial ecology
- Biogeochemical cycling
- Phytoplankton bloom dynamics
Background:
- Phytoplankton blooms are crucial for marine food webs, providing carbon and forming particulate organic matter.
- These particles support microbial communities and influence carbon sequestration.
- Understanding algal-bacterial interactions within blooms is key to marine ecosystem function.
Purpose of the Study:
- To investigate microbial communities and their functions within particulate organic matter during a spring phytoplankton bloom.
- To identify specific bacterial groups associated with different phytoplankton types (diatoms and dinoflagellates).
- To assess the potential for biogeochemical processes, such as sulfate reduction, within bloom particles in shallow waters.
Main Methods:
- Analysis of 16S and 18S ribosomal RNA gene amplicon sequences from particulate fractions (>10 µm).
- Metaproteome analysis to identify microbial functions.
- Sampling over 51 time points during a spring bloom in the North Sea (2018).
- Network analysis to determine co-occurrence patterns between bacteria and phytoplankton.
Main Results:
- Two distinct bacterial network modules were identified, linked to diatoms and dinoflagellates.
- Diatom-associated bacteria included sulfate-reducing Desulfobacterota and sulfur-oxidizing Ectothiorhodospiraceae.
- Metaproteomics confirmed the presence of enzymes for dissimilatory sulfate reduction within bloom particles.
- Anoxic niches capable of supporting sulfate reduction were found within the particle fraction.
Conclusions:
- Shallow phytoplankton blooms harbor anoxic microenvironments supporting sulfate reduction.
- Benthic-pelagic coupling plays a significant role in shaping microbiomes in shallow marine environments.
- Findings enhance understanding of algal-bacterial interactions and carbon export in coastal bloom systems.
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