Identifying metabolic alterations associated with coral growth anomalies using 1H NMR metabolomics
Tracey Schock, Erik Andersson, Russell D. Day, Thierry M. Work, Paul Anderson, Cheryl M. Woodley
Coral growth anomalies (GAs) are tumor-like protrusions that impact both the coral skeleton and softs tissues and are detrimental to coral health. These lesions are increasingly found throughout the tropics and are commonly associated with high human population density, yet little is known about the molecular pathology of the disease. Here, we investigate the metabolic impacts of GAs through 1H NMR metabolomics in Porites compressa tissues from a site of high disease prevalence (Coconut Island, Hawaii). We annotated 20 metabolites through complementary 1H and 1H–13C HSQC data that may bolster future efforts in coral metabolite annotation and increase confidence in pathway analyses. Mass of extracted metabolites was elevated in both GA and unaffected (normal tissue from a diseased colony) compared to reference (normal tissue from GA-free colony) samples, indicating elevated metabolic activity in GA-afflicted colonies. Metabolomic profiles exhibited substantial inter-colony variation with no distinction of group in multivariate PCA analyses, however, discriminant analysis identified 13 features that differed between GA and reference samples (VIP > 2.0). Multivariate average metabolic change vector (AMCV) analysis and univariate analysis (p < 0.05) identified 76 total features that differed between paired GA and unaffected samples. These features were largely annotated as unknowns, but 1-methylnicotinamide and trigonelline were found to be elevated in GA samples, while acetylcholine, betaine, glycine and histamine were lower in GA samples. Pathway analyses suggest that choline oxidation is decreased in GA samples, making this a pathway of interest for future targeted studies. Collectively, our results provide unique insights into GA pathophysiology by showing they alter both the absolute and relative metabolism of affected colonies and by identifying features (metabolites and unknowns) and metabolic pathways of interest going forward.
, Andersson, E.
, Day, R.
, Work, T.
, Anderson, P.
and Woodley, C.
Identifying metabolic alterations associated with coral growth anomalies using 1H NMR metabolomics, Plos Biology
(Accessed June 9, 2023)