Reconstruction of Coral Holobionts and Elucidation of the Causal Relationships among Symbiodiniaceae, Bacteria, and Coral through Single-Cell Raman Spectroscopy Metabolomics

The global decline of coral reefs underscores the urgency of understanding how corals respond to changing environmental conditions. As metaorganisms, or holobionts, corals rely on dynamic interactions with their associated microbial communities, with bacterial restructuring proposed as a potential mechanism of holobiont adaptation. Here, we reconstructed coral symbiosis in the bleached tissues of Acropora hyacinthus by introducing beneficial bacteria and thermally domesticated Symbiodiniaceae to assess their roles in bleaching recovery. Raman spectroscopy metabolomics (RS metabolomics) enables in situ detection, providing temporal evidence of metabolic exchange within the tripartite relationship among corals, Symbiodiniaceae, and associated bacteria.