GNPS - Population wide metabolomic analysis identifies peptide polymers as markers of coral stress independent of genotype

Effective coral conservation depends on understanding how stress impacts reef biology and health. Coral bleaching varies widely across individuals, yet its dependence on the genetic background of coral animals is poorly understood. Given this knowledge gap, we strove to identify genotype-independent metabolite markers of stress in two Hawaiian coral species, Montipora capitata and Pocillopora acuta. After exposure to thermal and pH stress, we used untargeted metabolomic profiling to investigate the physiological response of different coral genotypes (and ploidies) of each species. Our previous studies showed that dipeptides correlate with stress, and we found these metabolites showed a consistent response across different genotypes and ploidies. We further explored dark metabolites that are stress-responsive, and our tandem mass spectrometry (LC-MS2) results suggest that these candidates are larger tri- and tetrapeptides. Our results identify short peptides as critical intermediates in the coral stress response which provide diagnostic biomarkers for field applications.