Abstract
Stony corals, the engines and engineers of reef ecosystems, face unprecedented threats from anthropogenic environmental change. Corals are holobionts that comprise the cnidarian animal host and a diverse community of bacteria, archaea, viruses and eukaryotic microorganisms. Recent research shows that the bacterial microbiome has a pivotal role in coral biology. A healthy bacterial assemblage contributes to nutrient cycling and stress resilience, but pollution, overfishing and climate change can break down these symbiotic relationships, which results in disease, bleaching and, ultimately, coral death. Although progress has been made in characterizing the spatial-temporal diversity of bacteria, we are only beginning to appreciate their functional contribution. In this Review, we summarize the ecological and metabolic interactions between bacteria and other holobiont members, highlight the biotic and abiotic factors influencing the structure of bacterial communities and discuss the impact of climate change on these communities and their coral hosts. We emphasize how microbiome-based interventions can help to decipher key mechanisms underpinning coral health and promote reef resilience. Finally, we explore how recent technological developments may be harnessed to address some of the most pressing challenges in coral microbiology, providing a road map for future research in this field.
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Acknowledgements
C.R.V. acknowledges support by Deutsche Forschungsgemeinschaft (DFG; German Research Foundation) project numbers 433042944, 458901010 and 468583787. J.-B.R. is supported by an Australian Research Council Fellowship (FT210100100). C.P. is supported by a Junior Professorship Grant from Agence National de la Recherche (ANR; French National Research Agency) project number ANR-22-CPJ2-0113-01 and an associated start-up grant from the Institut Écologie et Environnement (INEE; Ecology and Environment Institute) of the Centre National de la Recherche Scientifique (CNRS; French National Centre for Scientific Research). R.S.P. acknowledges funding provided by KAUST (BAS/1/1095-01-01 and FCC/1/1976-40-01). S.A.A. is supported by Tamkeen under the NYU Abu Dhabi Research Institute Award to the NYUAD Center for Genomics and Systems Biology (ADHPG-CGSB). C.B.S. acknowledges funding provided by the NASA Exobiology Program (80NSSC23K0676). C.R.V. and R.S.P. acknowledge funding from KAUST (OSR-2021-NTGC-4984).
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C.R.V., R.S.P. and J.-B.R. researched data for the article, substantially contributed to discussion of content, wrote the article, and reviewed and edited the manuscript before submission. D.G.B. substantially contributed to discussion of content, and reviewed and edited the manuscript before submission. A.C., C.P., H.L., A.R.M., S.A.A. and C.B.S. researched data for the article, wrote the article, and reviewed and edited the manuscript before submission. C.R.V. conceived and, with M.D., designed the figures. M.D. illustrated the draft figures, wrote the article, and reviewed and edited the manuscript before submission.
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Voolstra, C.R., Raina, JB., Dörr, M. et al. The coral microbiome in sickness, in health and in a changing world. Nat Rev Microbiol (2024). https://doi.org/10.1038/s41579-024-01015-3
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DOI: https://doi.org/10.1038/s41579-024-01015-3