Diatom-Induced Chemical Interactions in Marine Ecosystems

Diatoms, as dominant photosynthetic microorganisms, drive up to half of marine primary production and exert profound influence on nutrient cycling and food-web dynamics through the release of bioactive chemicals. These compounds, notably oxylipins and other oxygenated lipids, serve multiple roles: as allelopathic agents inhibiting competitors or grazers, as infochemicals mediating cell–cell communication within blooms, and as modulators of interactions with bacteria, viruses and higher trophic levels. Diatom responses to nutrient fluctuations, viral infection or grazing pressure often entail the rapid synthesis and export of reactive metabolites, which can alter bloom longevity, foster microbial consortia through extracellular vesicle exchange and restructure planktonic communities. Such chemically mediated processes link cellular physiology to ecosystem-scale patterns, influence global carbon sequestration and offer potential avenues for biotechnological exploitation of diatom-derived compounds.

Research from Nature Portfolio

Recent studies have illuminated how diatoms manage ageing and recovery through targeted metabolite export. In bloom-forming cells starved of nutrients, Coscinodiscus radiatus packages reactive oxygen species, oxylipins and other toxic by-products into extracellular vesicles, effectively purging harmful metabolites and re-initiating cell division upon nutrient replenishment. This vesicle-mediated process is triggered and modulated by bacterial partners via chemical signals, revealing a cross-kingdom dialogue that governs bloom decline and resurgence. The work pinpoints methionine-cycle pathways as central to the rejuvenation response and underscores the dual role of bacterial signals in both inducing and benefiting from diatom metabolite flux.

Diatom-Induced Chemical Interactions in Marine Ecosystems publication trend

The graph below shows the total number of articles in diatom-induced chemical interactions in marine ecosystems across all publications each year (not limited to Nature Index journals).

Technical terms

Oxylipins: Oxygenated derivatives of polyunsaturated fatty acids involved in defence, signalling and allelopathy.

Extracellular vesicles: Membrane-bound particles released by cells to export metabolites, proteins and signalling molecules.

Lipoxygenase (LOX): Enzyme catalysing oxygen insertion into fatty acids, initiating oxylipin biosynthesis.

Allelopathy: Chemical inhibition of one organism by another through release of bioactive compounds.

Reactive oxygen species (ROS): Highly reactive molecules containing oxygen that can damage cellular components and serve as signals.

References

1. Multiple Roles of Diatom-Derived Oxylipins within Marine Environments and Their Potential Biotechnological Applications. Marine Drugs (2020).
2. Bacteria modulate microalgal aging physiology through the induction of extracellular vesicle production to remove harmful metabolites. Nature Microbiology (2024).
3. De novo transcriptome assembly of a lipoxygenase knock-down strain in the diatom Pseudo-nitzschia arenysensis. Scientific Data (2024).
4. Viral Infection Leads to a Unique Suite of Allelopathic Chemical Signals in Three Diatom Host–Virus Pairs. Marine Drugs (2024).
5. Structural and Functional Characterization of Lipoxygenases from Diatoms by Bioinformatics and Modelling Studies. Biomolecules (2024).