Corals are the "rainforests of the sea" – and, as it has now become clear, also their natural pharmacy. Coral reef ecosystems are home to more than one third of all marine plant and animal species. In symbiosis with microorganisms, corals produce natural substances that have scarcely been studied and that could be used to treat illnesses. However, with warming ocean temperatures, corals face the acute threat of extinction, and mass coral mortality is currently impacting oceans worldwide.

Ten years ago, the research vessel Tara collected thousands of coral samples from around the Pacific during an expedition for coral conservation under the participation of Christian Voolstra (University of Konstanz). In a study led by Shinichi Sunagawa and Jörn Piel at ETH Zurich and conducted in collaboration with the University of Konstanz, researchers have now completed genetic analysis on about 800 of these coral samples. Their genetic material revealed a previously undiscovered treasure: In symbiosis with the corals, microorganisms produce a massive arsenal of natural substances that could be very useful for treating illnesses in humans.

"For more than 99 percent of these species, we did not have any genomic information available, until now – they were unknown to science", says project leader Shinichi Sunagawa. "In the genes of microorganisms living in reefs, we found more potential for the production of bioactive substances than had previously been found in the entire open ocean." The research results were just published in the scientific journal Nature.

Invitation to the press conference: Tara Coral Expedition The research vessel Tara recently began a new mission: During the 18-month Tara Coral Expedition, a team of researchers will study the reefs of the Coral Triangle in the western Pacific. The aim is to find out which factors underlie the resistance of corals to adverse environmental conditions – and how it may inform intervention to halt mass extinctions of corals worldwide. In an online press conference on 4 March 2026, 17:00 CET, the team will present the Tara Coral Expedition and answer questions about the project. The press conference will take place by videoconference and in English. Zoom link The following people are available for interviews: Paola Furla, scientific director – Université Côte d’Azur, France Serge Planes, scientific director – CNRS, France Christian Voolstra, scientific director – University of Konstanz, Germany Register for the event and make interview requests by emailing eva@fondationtaraocean.org

If the biodiversity of coral reefs continues to drop, this will result in the permanent loss of thousands of mostly unknown species of microorganisms – and their "blueprints" for producing bioactive substances. "Molecular research on coral reefs has tremendous potential for biotechnological or medical applications", Jörn Piel says.

"Coral reefs are not just hotspots for biodiversity – they are also molecular treasure troves", adds Christian Voolstra, co-director of the Tara Coral Exhibition. "Each time we lose a reef, we also potentially lose one-of-a-kind microbially produced substances, before we even know they exist. This study makes it clear that protecting coral reefs is also an investment in future medical and biotechnological innovations – but the window of opportunity to do so is closing rapidly."


Original publication:
Wiederkehr, F., Paoli, L., Richter, D. et al. Coral microbiomes as reservoirs of unknown genomic and biosynthetic diversity. Nature (2026).
Link: https://www.nature.com/articles/s41586-026-10159-6
DOI: https://doi.org/10.1038/s41586-026-10159-6