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Summary Stony Coral Tissue Loss Disease (SCTLD) is a devastating disease. Since 2014, it has spread along the entire Florida Reef Tract and into the greater Caribbean. It was first detected in the United States Virgin Islands in January 2019. To more quickly identify microbial bioindicators of disease, we developed a rapid pipeline for microbiome sequencing. Over a span of 10 days we collected, processed and sequenced coral and near‐coral seawater microbiomes from diseased and apparently healthyColpophyllia natans,Montastraea cavernosa,Meandrina meandritesandOrbicella franksi. Analysis of bacterial and archaeal 16S ribosomal RNA gene sequences revealed 25 bioindicator amplicon sequence variants (ASVs) enriched in diseased corals. These bioindicator ASVs were additionally recovered in near‐coral seawater (<5 cm of coral surface), a potential reservoir for pathogens. Phylogenetic analysis of microbial bioindicators with sequences from the Coral Microbiome Database revealed thatVibrio,Arcobacter, Rhizobiaceae and Rhodobacteraceae sequences were related to disease‐associated coral bacteria and lineages novel to corals. Additionally, four ASVs (Algicola,Cohaesibacter,ThalassobiusandVibrio) were matches to microbes previously associated with SCTLD that should be targets for future research. Overall, this work suggests that a rapid sequencing framework paired with specialized databases facilitates identification of microbial disease bioindicators.
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Nutrient Enrichment Predominantly Affects Low Diversity Microbiomes in a Marine Trophic Symbiosis between Algal Farming Fish and Corals
While studies show that nutrient pollution shifts reef trophic interactions between fish, macroalgae, and corals, we know less about how the microbiomes associated with these organisms react to such disturbances. To investigate how microbiome dynamics are affected during nutrient pollution, we exposed replicate Porites lobata corals colonized by the fish Stegastes nigricans, which farm an algal matrix on the coral, to a pulse of nutrient enrichment over a two-month period and examined the microbiome of each partner using 16S amplicon analysis. We found 51 amplicon sequence variants (ASVs) shared among the three hosts. Coral microbiomes had the lowest diversity with over 98% of the microbiome dominated by a single genus, Endozoicomonas. Fish and algal matrix microbiomes were ~20 to 70× more diverse and had higher evenness compared to the corals. The addition of nutrients significantly increased species richness and community variability between samples of coral microbiomes but not the fish or algal matrix microbiomes, demonstrating that coral microbiomes are less resistant to nutrient pollution than their trophic partners. Furthermore, the 51 common ASVs within the 3 hosts indicate microbes that may be shared or transmitted between these closely associated organisms, including Vibrionaceae bacteria, many of which can be pathogenic to corals.
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- PAR ID:
- 10296478
- Date Published:
- Journal Name:
- Microorganisms
- Volume:
- 9
- Issue:
- 9
- ISSN:
- 2076-2607
- Page Range / eLocation ID:
- 1873
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/microorganisms9091873
