Comparing Bacterial Community Composition of Healthy and Dark Spot-Affected Siderastrea siderea in Florida and the Caribbean

Coral disease is one of the major causes of reef degradation. Dark Spot Syndrome (DSS) was described in the early 1990''s as brown or purple amorphous areas of tissue on a coral and has since become one of the most prevalent diseases reported on Caribbean reefs. It has been identified in a number of coral species, but there is debate as to whether it is in fact the same disease in different corals. Further, it is questioned whether these macroscopic signs are in fact diagnostic of an infectious disease at all. The most commonly affected species in the Caribbean is the massive starlet coral Siderastrea siderea. We sampled this species in two locations, Dry Tortugas National Park and Virgin Islands National Park. Tissue biopsies were collected from both healthy colonies and those with dark spot lesions. Microbial-community DNA was extracted from coral samples (mucus, tissue, and skeleton), amplified using bacterial-specific primers, and applied to PhyloChip G3 microarrays to examine the bacterial diversity associated with this coral. Samples were also screened for the presence of a fungal ribotype that has recently been implicated as a causative agent of DSS in another coral species, but the amplifications were unsuccessful. S. siderea samples did not cluster consistently based on health state (i.e., normal versus dark spot). Various bacteria, including Cyanobacteria and Vibrios, were observed to have increased relative abundance in the discolored tissue, but the patterns were not consistent across all DSS samples. Overall, our findings do not support the hypothesis that DSS in S. siderea is linked to a bacterial pathogen or pathogens. This dataset provides the most comprehensive overview to date of the bacterial community associated with the scleractinian coral S. siderea.     

The corallivorous invertebrate Drupella aids in transmission of brown band disease on the Great Barrier Reef

Brown band disease (BrB) is an increasingly prevalent coral disease in the Indo-Pacific, but although the macroscopic signs of BrB have been associated with the ciliate Philaster guamensis, many aspects of its ecology remain unknown, particularly how the disease is transmitted among coral colonies. The aim of this study was to assess biotic factors affecting BrB transmission, explicitly testing whether corallivorous species contribute to disease spread. Several fish species were observed feeding on diseased tissue in the field, but did not influence either the progression or transmission rates of BrB on coral colonies in situ. In aquarium-based experiments, the butterflyfish Chaetodon aureofasciatus neither aided nor hindered the transmission of BrB from infected to uninfected corals. In contrast, the coral-feeding gastropod Drupella sp. was a highly effective vector of BrB, infecting more than 40 % of experimental colonies. This study also demonstrated the importance of injury in facilitating BrB infection, supporting the hypothesis that the BrB pathogen invades compromised coral tissue. In conclusion, disturbances and corallivorous activities that injure live corals are likely to contribute to increased occurrence of BrB provided that feeding scars create entry wounds sufficiently extensive to facilitate infection. These findings increase the understanding of the ecology of BrB, enabling better predictions of the prevalence and severity of this disease, and informing strategies for managing the impact of BrB on coral reefs.     

Scleractinian coral diseases in south Florida: incidence, species susceptibility, and mortality

There are limited quantitative data available documenting the natural, or non-epizootic, occurrence of scleractinian coral diseases over multiple years. Individual coral colonies exhibiting black band disease (BBD), white plague (WP), dark spots syndrome (DSS), and white band disease (WBD) were monitored 3 times per year on 5 south Florida reefs over a 2 yr period. Surveys included measurements of coral population composition, coral diversity, disease type, coral species affected, colony size, percent of colony affected, and the number of lesions or active infections per colony. Data on re-infections of the same colonies, multiple infections per colony, disease duration, disease-associated tissue mortality, and coral recruitment are also presented. A total of 674 coral colonies exhibiting coral diseases were tagged and monitored. DSS was the most common syndrome (n = 620 infected colonies), but BBD and WP infections caused the largest amount of coral tissue death. The only disease that exhibited a linear increase in incidence with elevated temperature was BBD. DSS and BBD were the most persistent conditions, and WP infections were comparatively short-lived, with obvious signs of disease typically disappearing after 2 to 3 mo. The only disease that caused total colony death as oppposed to partial mortality during the survey period was WBD. WP and DSS incidence was significantly positively correlated with the relative frequency of the species most commonly affected by each disease at each study site. Of the 61 colonies examined in the recruitment survey, only 5 scleractinian coral recruits were identified. The most commonly recorded colonizer of exposed coral skeleton was filamentous/turf algae, thus indicating the potential for a shift towards algal-dominated reef communities.     

Algae as Reservoirs for Coral Pathogens

Benthic algae are associated with coral death in the form of stress and disease. It''s been proposed that they release exudates, which facilitate invasion of potentially pathogenic microbes at the coral-algal interface, resulting in coral disease. However, the original source of these pathogens remains unknown. This study examined the ability of benthic algae to act as reservoirs of coral pathogens by characterizing surface associated microbes associated with major Caribbean and Indo-Pacific algal species/types and by comparing them to potential pathogens of two dominant coral diseases: White Syndrome (WS) in the Indo-Pacific and Yellow Band Disease (YBD) in the Caribbean. Coral and algal sampling was conducted simultaneously at the same sites to avoid spatial effects. Potential pathogens were defined as those absent or rare in healthy corals, increasing in abundance in healthy tissues adjacent to a disease lesion, and dominant in disease lesions. Potentially pathogenic bacteria were detected in both WS and YBD and were also present within the majority of algal species/types (54 and 100% for WS and YBD respectively). Pathogenic ciliates were associated only with WS and not YBD lesions and these were also present in 36% of the Indo-Pacific algal species. Although potential pathogens were associated with many algal species, their presence was inconsistent among replicate algal samples and detection rates were relatively low, suggestive of low density and occurrence. At the community level, coral-associated microbes irrespective of the health of their host differed from algal-associated microbes, supporting that algae and corals have distinctive microbial communities associated with their tissue. We conclude that benthic algae are common reservoirs for a variety of different potential coral pathogens. However, algal-associated microbes alone are unlikely to cause coral death. Initial damage or stress to the coral via other competitive mechanisms is most likely a prerequisite to potential transmission of these pathogens.     

Bacterial communities associated with healthy and Acropora white syndrome-affected corals from American Samoa

Acropora white syndrome (AWS) is characterized by rapid tissue loss revealing the white underlying skeleton and affects corals worldwide; however, reports of causal agents are conflicting. Samples were collected from healthy and diseased corals and seawater around American Samoa and bacteria associated with AWS characterized using both culture-dependent and culture-independent methods, from coral mucus and tissue slurries, respectively. Bacterial 16S rRNA gene clone libraries derived from coral tissue were dominated by the Gammaproteobacteria, and Jaccard's distances calculated between the clone libraries showed that those from diseased corals were more similar to each other than to those from healthy corals. 16S rRNA genes from 78 culturable coral mucus isolates also revealed a distinct partitioning of bacterial genera into healthy and diseased corals. Isolates identified as Vibrionaceae were further characterized by multilocus sequence typing, revealing that whilst several Vibrio spp. were found to be associated with AWS lesions, a recently described species, Vibrio owensii, was prevalent amongst cultured Vibrio isolates. Unaffected tissues from corals with AWS had a different microbiota than normal Acropora as found by others. Determining whether a microbial shift occurs prior to disease outbreaks will be a useful avenue of pursuit and could be helpful in detecting prodromal signs of coral disease prior to manifestation of lesions.     

The bacterial ecology of a plague-like disease affecting the Caribbean coral Montastrea annularis

The bacterial communities associated with the Caribbean coral Montastrea annularis showing tissue lesions indicative of a White Plague (WP)-like disease were investigated. Two molecular screening techniques using bacterial 16S rDNA genes were used and demonstrated distinct differences between the bacterial communities of diseased and non-diseased coral tissues, and also in relation to the proximity of tissue lesions on diseased corals. Differences between non-diseased corals and the apparently healthy tissues remote from the tissue lesion in affected corals indicates a 'whole coral' response to a relatively small area of infection with a perturbation in the normal microbial flora occurring prior to the onset of visible signs of disease. These whole organism changes in the microbial flora may serve as a bioindicator of environmental stress and disease. There were striking similarities between the 16S rDNA sequence composition associated with the WP-like disease studied here and that previously reported in association with black band disease (BBD) in coral. Similarities included the presence of a potential pathogen, an alpha-proteobacterium identified as the causal agent of juvenile oyster disease (JOD). The WP-like disease studied here is apparently different to WP Type ii because the bacterial species previously identified as the causal agent of WP Type ii was not detected, although the symptoms of the two diseases are similar.     

Crown-of-thorns starfish predation and physical injuries promote brown band disease on corals

Brown band (BrB) disease manifests on corals as a ciliate-dominated lesion that typically progresses rapidly causing extensive mortality, but it is unclear whether the dominant ciliate Porpostoma guamense is a primary or an opportunistic pathogen, the latter taking advantage of compromised coral tissue or depressed host resistance. In this study, manipulative aquarium-based experiments were used to investigate the role of P. guamense as a pathogen when inoculated onto fragments of the coral Acropora hyacinthus that were either healthy, preyed on by Acanthaster planci (crown-of-thorns starfish; COTS), or experimentally injured. Following ciliate inoculation, BrB lesions developed on all of COTS-predated fragments (n = 9 fragments) and progressed up to 4.6 ± 0.3 cm d^?1, resulting in ~70 % of coral tissue loss after 4 d. Similarly, BrB lesions developed rapidly on experimentally injured corals and ~38 % of coral tissue area was lost 60 h after inoculation. In contrast, no BrB lesions were observed on healthy corals following experimental inoculations. A choice experiment demonstrated that ciliates are strongly attracted to physically injured corals, with over 55 % of inoculated ciliates migrating to injured corals and forming distinct lesions, whereas ciliates did not migrate to healthy corals. Our results indicate that ciliates characteristic of BrB disease are opportunistic pathogens that rapidly migrate to and colonise compromised coral tissue, leading to rapid coral mortality, particularly following predation or injury. Predicted increases in tropical storms, cyclones, and COTS outbreaks are likely to increase the incidence of coral injury in the near future, promoting BrB disease and further contributing to declines in coral cover.     

Histiocytose langerhansienne osseuse multifocale : intérêt de la scintigraphie osseuse planaire

Langerhans cell histiocytosis is a disease of the reticuloendothelial system characterized by a clonal proliferation of dendritic cells of Langerhans. This is a rare disease that primarily affects children and young adults. It can take many forms, from a single eosinophilic granuloma to widespread lesions involving multisystem life-threatening. Bone involvement is the most common, it can be uni- or multifocal. We report a case of multifocal bone Langerhans cell histiocytosis, revealed in a child aged 3 years and touched his left temporal bone and right femur. The bone scintigraphy has found a third location in right scapular. The outcome was favorable after chemotherapy. The bone lesions are characterized by lytic lesions and are responsible for pain, swelling and fractures. All the imaging techniques (radiographs, CT, and MRI) contribute to the formation of the diagnosis. Bone scintigraphy is a very sensitive examination that allows the initial staging and follow-up on treatment of skeletal manifestations.     

The Role of Coral-Associated Bacterial Communities in Australian Subtropical White Syndrome of Turbinaria mesenterina

Australian Subtropical White Syndrome (ASWS) is an infectious, temperature dependent disease of the subtropical coral Turbinaria mesenterina involving a hitherto unknown transmissible causative agent. This report describes significant changes in the coral associated bacterial community as the disease progresses from the apparently healthy tissue of ASWS affected coral colonies, to areas of the colony affected by ASWS lesions, to the dead coral skeleton exposed by ASWS. In an effort to better understand the potential roles of bacteria in the formation of disease lesions, the effect of antibacterials on the rate of lesion progression was tested, and both culture based and culture independent techniques were used to investigate the bacterial communities associated with colonies of T. mesenterina. Culture-independent analysis was performed using the Oligonucleotide Fingerprinting of Ribosomal Genes (OFRG) technique, which allowed a library of 8094 cloned bacterial 16S ribosomal genes to be analysed. Interestingly, the bacterial communities associated with both healthy and disease affected corals were very diverse and ASWS associated communities were not characterized by a single dominant organism. Treatment with antibacterials had a significant effect on the rate of progress of disease lesions (p = 0.006), suggesting that bacteria may play direct roles as the causative agents of ASWS. A number of potential aetiological agents of ASWS were identified in both the culture-based and culture-independent studies. In the culture-independent study an Alphaproteobacterium closely related to Roseovarius crassostreae, the apparent aetiological agent of juvenile oyster disease, was found to be significantly associated with disease lesions. In the culture-based study Vibrio harveyi was consistently associated with ASWS affected coral colonies and was not isolated from any healthy colonies. The differing results of the culture based and culture-independent studies highlight the importance of using both approaches in the investigation of microbial communities.     

Coral Disease Diagnostics: What's between a Plague and a Band?

Recently, reports of coral disease have increased significantly across the world's tropical oceans. Despite increasing efforts to understand the changing incidence of coral disease, very few primary pathogens have been identified, and most studies remain dependent on the external appearance of corals for diagnosis. Given this situation, our current understanding of coral disease and the progression and underlying causes thereof is very limited. In the present study, we use structural and microbial studies to differentiate different forms of black band disease: atypical black band disease and typical black band disease. Atypical black band diseased corals were infected with the black band disease microbial consortium yet did not show any of the typical external signs of black band disease based on macroscopic observations. In previous studies, these examples, here referred to as atypical black band disease, would have not been correctly diagnosed. We also differentiate white syndrome from white diseases on the basis of tissue structure and the presence/absence of microbial associates. White diseases are those with dense bacterial communities associated with lesions of symbiont loss and/or extensive necrosis of tissues, while white syndromes are characteristically bacterium free, with evidence for extensive programmed cell death/apoptosis associated with the lesion and the adjacent tissues. The pathology of coral disease as a whole requires further investigation. This study emphasizes the importance of going beyond the external macroscopic signs of coral disease for accurate disease diagnosis.     

Histopathological methods for the investigation of microbial communities associated with disease lesions in reef corals

AIMS: To determine the spatial structure of microbial communities associated with disease lesions of reef corals (Scleractinia). METHODS AND RESULTS: Agarose pre-embedding preserved the structure of the disease lesion and surrounding tissues prior to demineralization of the carbonate exoskeleton and embedding in resin. Fluorescence in situ hybridization (FISH) was used to localize bacteria in the lesions of various diseases. CONCLUSIONS: The techniques successfully preserved the in situ spatial structure of degenerated coral tissues. In one case (white plague disease), significant bacterial populations were found only in fragmented remnants of degenerated coral tissues at the lesion boundary that would not have been detected using conventional histopathological techniques. SIGNIFICANCE AND IMPACT OF THE STUDY: Determining the composition, spatial structure and dynamics of microbial communities within the disease lesions is necessary to understand the process of disease progression. The methods described may be applicable to a wide range of diseases involving necrotic lesion formation and requiring extensive tissue processing, such as skeleton demineralization.     

Coral disease diagnostics: what's between a plague and a band?

Recently, reports of coral disease have increased significantly across the world's tropical oceans. Despite increasing efforts to understand the changing incidence of coral disease, very few primary pathogens have been identified, and most studies remain dependent on the external appearance of corals for diagnosis. Given this situation, our current understanding of coral disease and the progression and underlying causes thereof is very limited. In the present study, we use structural and microbial studies to differentiate different forms of black band disease: atypical black band disease and typical black band disease. Atypical black band diseased corals were infected with the black band disease microbial consortium yet did not show any of the typical external signs of black band disease based on macroscopic observations. In previous studies, these examples, here referred to as atypical black band disease, would have not been correctly diagnosed. We also differentiate white syndrome from white diseases on the basis of tissue structure and the presence/absence of microbial associates. White diseases are those with dense bacterial communities associated with lesions of symbiont loss and/or extensive necrosis of tissues, while white syndromes are characteristically bacterium free, with evidence for extensive programmed cell death/apoptosis associated with the lesion and the adjacent tissues. The pathology of coral disease as a whole requires further investigation. This study emphasizes the importance of going beyond the external macroscopic signs of coral disease for accurate disease diagnosis.     

Spatial and temporal patterns of scleractinian coral, soft coral, and zoanthid disease on a remote, near-pristine coral reef (Palmyra Atoll, central Pacific)

There is an urgent need for accurate baselines of coral disease prevalence across our oceans in order for sudden or unnatural changes to be recognized. Palmyra Atoll allows us to study disease dynamics under near-pristine, functionally intact conditions. We examined disease prevalence among all known species of scleractinian coral, soft coral and zoanthid (Palythoa) at a variety of coral reef habitats at Palmyra over a 2 yr period. In 2008, overall disease prevalence across the atoll was low (0.33%), but higher on the shallower backreef (0.88%) and reef terrace (0.80%) than on the deeper forereef (0.09%). Scleractinian coral disease prevalence was higher (0.30%) than were soft coral and zoanthid disease (0.03% combined). Growth anomalies (GAs) were the most commonly encountered lesions, with scleractinian species in the genera Astreopora (2.12%), Acropora (1.30%), and Montipora (0.98%) showing the highest prevalence atoll-wide. Discoloration necrosis (DN) was most prevalent in the zoanthid Palythoa tuberculosa (1.18%), although the soft coral Sinulana and Montipora also had a prevalence of 0.44 and 0.01%, respectively. Overall disease prevalence within permanently marked transects increased from 0.65% in 2008 to 0.79% in 2009. Palythoa DN contributed most to this increased prevalence, which coincided with rising temperatures during the 2009 El Ni?o. GAs on the majority of susceptible genera at Palmyra increased in number over time, and led to tissue death. Host distribution and environmental factors (e.g., temperature) appear to be important for determining spatiotemporal patterns of disease at Palmyra. More sophisticated analyses are required to tease apart the likely inter-correlated proximate drivers of disease occurrence on remote, near-pristine reefs.     

Epidemiology of skeletal eroding band on the Great Barrier Reef and the role of injury in the initiation of this widespread coral disease

Skeletal eroding band (SEB), which manifests as dense aggregations of the ciliate Halofolliculina corallasia, was the first coral disease described from the Indo-Pacific. Little is known about its etiology or impact. This study describes the distribution, prevalence and host range of SEB on a 500 km extent of the Great Barrier Reef (GBR), together with in situ rates of progression and infection following experimental injury. SEB occurred on 90–100% of reefs surveyed (n=18) in each of 3 years, demonstrating that SEB is widely distributed and persistent. SEB had the highest prevalence of any disease, affecting approximately 2% of 283,486 scleractinians and hydrocorals surveyed. Its host range was large, affecting 12 families and at least 82 scleractinian species, as well as the hydrocoral, Millepora. Corals in the families Pocilloporidae and Acroporidae were most susceptible, the former being up to five times more susceptible than other families. Progressive tissue loss was recorded on 95% of Acropora muricata colonies monitored (n = 18), with rates of SEB progression averaging ∼2 mm/day. Injury experiments demonstrated that H. corallasia, the putative pathogen of SEB, readily colonised recently exposed coral skeleton in the absence of a vector, but did not colonise intact coral tissue. Invading ciliates failed to form band-like aggregations associated with progressive tissue loss on any of three coral species tested experimentally, suggesting that, while H. corallasia readily colonises recently exposed coral skeleton, it may not be sufficient in itself to cause tissue mortality. Interactions with additional agents or factors, increasing ciliate virulence or lowering disease resistance of coral hosts may be required before halofolliculinid infections become associated with tissue loss.     

Does Dark-Spot Syndrome Experimentally Transmit among Caribbean Corals?

Over the last half-century, coral diseases have contributed to the rapid decline of coral populations throughout the Caribbean region. Some coral diseases appear to be potentially infectious, yet little is known about their modes of transmission. This study experimentally tested whether dark-spot syndrome on Siderastrea siderea was directly or indirectly transmissible to neighboring coral colonies. We also tested whether open wounds were necessary to facilitate disease transmission. At the completion of the experiments, we sampled bacterial communities on diseased, exposed, and healthy coral colonies to determine whether bacterial pathogens had transmitted to the susceptible colonies. We saw no evidence of either direct or waterborne transmission of dark-spot syndrome, and corals that received lesions by direct contact with diseased tissue, healed and showed no signs of infection. There were no significant differences among bacterial communities on healthy, exposed, and diseased colonies, although nine individual ribotypes were significantly higher in diseased corals compared with healthy and exposed corals, indicating a lack of transmission. Although our experiments do not fully refute the possibility that dark-spot syndrome is infectious and transmissible, our results suggest that in situ macroscopic signs of dark-spot syndrome are not always contagious.     

Bacterial communities associated with the mucopolysaccharide layers of three coral species affected and unaffected with dark spots disease

Dark spots disease (DSD) is a relatively new coral disease that has become one of the most prevalent afflictions in the Caribbean Sea. To partially characterize bacterial communities associated with DSD, carbon utilization patterns of bacterial strains isolated from the surface mucopolysaccharide layers of healthy and DSD-affected Montastraea annularis, Montastraea faveolata, and Siderastrea siderea were compared with each other and with bacterial strains isolated from the water column by using cluster analysis. Differences between healthy and diseased corals were found and were greatest for M. annularis than for the other species. A metabolic group of bacteria similar to Vibrio carchariae was found to be unique to diseased samples. Inoculation experiments on healthy corals did not result in the development of disease signs. However, our results support the hypothesis that stress (in this case disease) alters the normal microbiota in the coral surface mucopolysaccaride layers. Studies are continuing to determine the pathogenic agent(s) responsible for DSD.     

Contrasting Lesion Dynamics of White Syndrome among the scleractinian corals Porites spp

White syndrome (WS) is currently the most prevalent disease of scleractinian corals in the Indo-Pacific region, with an ability to exist in both epizootic and enzootic states. Here, we present results of an examination of WS lesion dynamics and show that potentially associated traits of host morphology (i.e., branching vs. massive), lesion size, and tissue deposition rate influence disease severity and recovery. Lesion healing rate was positively correlated with initial lesion size in both morphologies, but the rate at which lesions healed differed between morphologies. New lesions in branching Porites cylindrica appeared less frequently, were smaller and healed more quickly, but were more abundant than in closely-related massive Porites sp(p). The positive association between lesion size and healing rate was partly explained by geometry; branching limited lesion maximum size, and larger lesion margins contained more polyps producing new tissue, resulting in faster healing. However, massive colonies deposited tissue more slowly than branching colonies, resulting in slower recovery and more persistent lesions. Corallite size and density did not differ between species and did not, therefore, influence healing rate. We demonstrated multiple modes of pathogen transmission, which may be influenced by the greater potential for pathogen entrainment in branching vs. massive morphologies. We suggest that attributes such as colony morphology and species-specific growth rates require consideration as we expand our understanding of disease dynamics in colonial organisms such as coral.     

Selective feeding by coral reef fishes on coral lesions associated with brown band and black band disease

Recent studies have suggested that corallivorous fishes may be vectors for coral disease, but the extent to which fishes actually feed on and thereby potentially transmit coral pathogens is largely unknown. For this study, in situ video observations were used to assess the level to which fishes fed on diseased coral tissues at Lizard Island, northern Great Barrier Reef. Surveys conducted at multiple locations around Lizard Island revealed that coral disease prevalence, especially of brown band disease (BrB), was higher in lagoon and backreef locations than in exposed reef crests. Accordingly, video cameras were deployed in lagoon and backreef habitats to record feeding by fishes during 1-h periods on diseased sections of each of 44 different coral colonies. Twenty-five species from five fish families (Blennidae, Chaetodontidae, Gobiidae, Labridae and Pomacentridae) were observed to feed on infected coral tissues of staghorn species of Acropora that were naturally infected with black band disease (BBD) or brown band disease (BrB). Collectively, these fishes took an average of 18.6 (±5.6 SE) and 14.3 (±6.1 SE) bites per hour from BBD and BrB lesions, respectively. More than 40% (408/948 bites) and nearly 25% (314/1319 bites) of bites were observed on lesions associated with BBD and BrB, respectively, despite these bands each representing only about 1% of the substratum available. Moreover, many corallivorous fishes (Labrichthys unilineatus, Chaetodon aureofasciatus, C. baronessa, C. lunulatus, C. trifascialis, Cheiloprion labiatus) selectively targeted disease lesions over adjacent healthy coral tissues. These findings highlight the important role that reef fishes may play in the dynamics of coral diseases, either as vectors for the spread of coral disease or in reducing coral disease progression through intensive and selective consumption of diseased coral tissues.     

Identifying metabolic alterations associated with coral growth anomalies using 1H NMR metabolomics

Coral growth anomalies (GAs) are tumor-like protrusions that are detrimental to coral health, affecting both the coral skeleton and soft tissues. 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 nuclear magnetic resonance (NMR) metabolomics in Porites compressa tissues from a site of high disease prevalence (Coconut Island, Hawaii). We putatively identified 18 metabolites (8.1% of total annotated features) through complementary ¹H and ¹H–¹³C heteronuclear single quantum correlation NMR data that increase confidence in pathway analyses and may bolster future coral metabolite annotation efforts. Extract yield was elevated in both GA and unaffected (normal tissue from a diseased colony) compared to reference (normal tissue from GA-free colony) samples, potentially indicating elevated metabolic activity in GA-impacted colonies. Relatively high variation in metabolomic profiles among coral samples of the same treatment (i.e., inter-colony variation) confounded data interpretation, however, analyses of paired GA and unaffected samples identified 73 features that differed between these respective metabolome types. These features were largely annotated as unknowns, but 1-methylnicotinamide and trigonelline were found to be elevated in GA samples, while betaine, glycine, and histamine were lower in GA samples. Pathway analyses indicate decreased choline oxidation in GA samples, making this a pathway of interest for future targeted studies. Collectively, our results provide unique insights into GA pathophysiology by showing these lesions alter both the absolute and relative metabolism of affected colonies and by identifying features (metabolites and unknowns) and metabolic pathways of interest in GA pathophysiology going forward.