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Miller TC, Bentlage B. Seasonal dynamics and environmental drivers of tissue and mucus microbiomes in the staghorn coral Acropora pulchra. PeerJ 2024; 12:e17421. [PMID: 38827308 PMCID: PMC11144401 DOI: 10.7717/peerj.17421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 04/28/2024] [Indexed: 06/04/2024] Open
Abstract
Background Rainfall-induced coastal runoff represents an important environmental impact in near-shore coral reefs that may affect coral-associated bacterial microbiomes. Shifts in microbiome community composition and function can stress corals and ultimately cause mortality and reef declines. Impacts of environmental stress may be site specific and differ between coral microbiome compartments (e.g., tissue versus mucus). Coastal runoff and associated water pollution represent a major stressor for near-shore reef-ecosystems in Guam, Micronesia. Methods Acropora pulchra colonies growing on the West Hagåtña reef flat in Guam were sampled over a period of 8 months spanning the 2021 wet and dry seasons. To examine bacterial microbiome diversity and composition, samples of A. pulchra tissue and mucus were collected during late April, early July, late September, and at the end of December. Samples were collected from populations in two different habitat zones, near the reef crest (farshore) and close to shore (nearshore). Seawater samples were collected during the same time period to evaluate microbiome dynamics of the waters surrounding coral colonies. Tissue, mucus, and seawater microbiomes were characterized using 16S DNA metabarcoding in conjunction with Illumina sequencing. In addition, water samples were collected to determine fecal indicator bacteria (FIB) concentrations as an indicator of water pollution. Water temperatures were recorded using data loggers and precipitation data obtained from a nearby rain gauge. The correlation structure of environmental parameters (temperature and rainfall), FIB concentrations, and A. pulchra microbiome diversity was evaluated using a structural equation model. Beta diversity analyses were used to investigate spatio-temporal trends of microbiome composition. Results Acropora pulchra microbiome diversity differed between tissues and mucus, with mucus microbiome diversity being similar to the surrounding seawater. Rainfall and associated fluctuations of FIB concentrations were correlated with changes in tissue and mucus microbiomes, indicating their role as drivers of A. pulchra microbiome diversity. A. pulchra tissue microbiome composition remained relatively stable throughout dry and wet seasons; tissues were dominated by Endozoicomonadaceae, coral endosymbionts and putative indicators of coral health. In nearshore A. pulchra tissue microbiomes, Simkaniaceae, putative obligate coral endosymbionts, were more abundant than in A. pulchra colonies growing near the reef crest (farshore). A. pulchra mucus microbiomes were more diverse during the wet season than the dry season, a distinction that was also associated with drastic shifts in microbiome composition. This study highlights the seasonal dynamics of coral microbiomes and demonstrates that microbiome diversity and composition may differ between coral tissues and the surface mucus layer.
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Affiliation(s)
- Therese C. Miller
- Marine Laboratory, University of Guam, Mangilao, Guam, USA
- Institute of Marine Science, University of Auckland, Auckland, New Zealand
- Cawthron Institute, Nelson, New Zealand
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Cardoso PM, Hill LJ, Villela HDM, Vilela CLS, Assis JM, Rosado PM, Rosado JG, Chacon MA, Majzoub ME, Duarte GAS, Thomas T, Peixoto RS. Localization and symbiotic status of probiotics in the coral holobiont. mSystems 2024; 9:e0026124. [PMID: 38606974 PMCID: PMC11097643 DOI: 10.1128/msystems.00261-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Accepted: 03/20/2024] [Indexed: 04/13/2024] Open
Abstract
Corals establish symbiotic relationships with microorganisms, especially endosymbiotic photosynthetic algae. Although other microbes have been commonly detected in coral tissues, their identity and beneficial functions for their host are unclear. Here, we confirm the beneficial outcomes of the inoculation of bacteria selected as probiotics and use fluorescence in situ hybridization (FISH) to define their localization in the coral Pocillopora damicornis. Our results show the first evidence of the inherent presence of Halomonas sp. and Cobetia sp. in native coral tissues, even before their inoculation. Furthermore, the relative enrichment of these coral tissue-associated bacteria through their inoculation in corals correlates with health improvements, such as increases in photosynthetic potential, and productivity. Our study suggests the symbiotic status of Halomonas sp. and Cobetia sp. in corals by indicating their localization within coral gastrodermis and epidermis and correlating their increased relative abundance through active inoculation with beneficial outcomes for the holobiont. This knowledge is crucial to facilitate the screening and application of probiotics that may not be transient members of the coral microbiome. IMPORTANCE Despite the promising results indicating the beneficial outcomes associated with the application of probiotics in corals and some scarce knowledge regarding the identity of bacterial cells found within the coral tissue, the correlation between these two aspects is still missing. This gap limits our understanding of the actual diversity of coral-associated bacteria and whether these symbionts are beneficial. Some researchers, for example, have been suggesting that probiotic screening should only focus on the very few known tissue-associated bacteria, such as Endozoicomonas sp., assuming that the currently tested probiotics are not tissue-associated. Here, we provide specific FISH probes for Halomonas sp. and Cobetia sp., expand our knowledge of the identity of coral-associated bacteria and confirm the probiotic status of the tested probiotics. The presence of these beneficial microorganisms for corals (BMCs) inside host tissues and gastric cavities also supports the notion that direct interactions with the host may underpin their probiotic role. This is a new breakthrough; these results argue against the possibility that the positive effects of BMCs are due to factors that are not related to a direct symbiotic interaction, for example, that the host simply feeds on inoculated bacteria or that the bacteria change the water quality.
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Affiliation(s)
- P. M. Cardoso
- Red Sea Research Center, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - L. J. Hill
- Laboratory of Molecular Microbial Ecology, Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - H. D. M. Villela
- Red Sea Research Center, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - C. L. S. Vilela
- Laboratory of Molecular Microbial Ecology, Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - J. M. Assis
- Laboratory of Molecular Microbial Ecology, Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - P. M. Rosado
- Red Sea Research Center, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - J. G. Rosado
- Red Sea Research Center, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - M. A. Chacon
- Laboratory of Molecular Microbial Ecology, Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - M. E. Majzoub
- Center for Marine Science and Innovation; School of Biological, Earth and Environmental Sciences, The University of New South Wales, Sydney, New South Wales, Australia
| | - G. A. S. Duarte
- Red Sea Research Center, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
- Laboratory of Molecular Microbial Ecology, Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - T. Thomas
- Center for Marine Science and Innovation; School of Biological, Earth and Environmental Sciences, The University of New South Wales, Sydney, New South Wales, Australia
| | - R. S. Peixoto
- Red Sea Research Center, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
- Computational Biology Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Marine Science and Bioscience Programs, Biological, Environmental and Engineering Sciences Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
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van de Water JAJM, Allemand D, Ferrier‐Pagès C. Bacterial symbionts of the precious coral Corallium rubrum are differentially distributed across colony-specific compartments and differ among colormorphs. ENVIRONMENTAL MICROBIOLOGY REPORTS 2024; 16:e13236. [PMID: 38444282 PMCID: PMC10915489 DOI: 10.1111/1758-2229.13236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 01/18/2024] [Indexed: 03/07/2024]
Abstract
Corals engage in symbioses with micro-organisms that provide nutrients and protect the host. Where the prokaryotic microbes perform their symbiotic functions within a coral is, however, poorly understood. Here, we studied the tissue-specific microbiota of the coral Corallium rubrum by dissecting its tissues from the skeleton and separating the white polyps from the red-coloured coenenchyme, followed by 16S rRNA gene metabarcoding of the three fractions. Dissection was facilitated by incubating coral fragments in RNAlater, which caused tissues to detach from the skeleton. Our results show compartmentalisation of the microbiota. Specifically, Endozoicomonas, Parcubacteria and a Gammaproteobacteria were primarily located in polyps, whereas Nitrincolaceae and one Spirochaeta phylotype were found mainly in the coenenchyme. The skeleton-associated microbiota was distinct from the microbiota in the tissues. Given the difference in tissue colour and microbiota of the polyps and coenenchyme, we analysed the microbiota of three colormorphs of C. rubrum (red, pink, white), finding that the main difference was a very low abundance of Spirochaeta in white colormorphs. While the functions of C. rubrum's symbionts are unknown, their localisation within the colony suggests that microhabitats exist, and the presence of Spirochaeta appears to be linked to the colour of C. rubrum.
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Affiliation(s)
- Jeroen A. J. M. van de Water
- Unité de Recherche sur la Biologie des Coraux Précieux CSM – CHANELCentre Scientifique de MonacoMonacoPrincipality of Monaco
- Coral Ecophysiology Team, Department of Marine BiologyCentre Scientifique de MonacoMonacoPrincipality of Monaco
- Department of Estuarine & Delta SystemsRoyal Netherlands Institute for Sea ResearchYersekeThe Netherlands
| | - Denis Allemand
- Centre Scientifique de MonacoMonacoPrincipality of Monaco
| | - Christine Ferrier‐Pagès
- Coral Ecophysiology Team, Department of Marine BiologyCentre Scientifique de MonacoMonacoPrincipality of Monaco
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Chan YF, Chen YH, Yu SP, Chen HJ, Nozawa Y, Tang SL. Reciprocal transplant experiment reveals multiple factors influencing changes in coral microbial communities across climate zones. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 907:167929. [PMID: 37863230 DOI: 10.1016/j.scitotenv.2023.167929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Revised: 10/12/2023] [Accepted: 10/17/2023] [Indexed: 10/22/2023]
Abstract
Previous studies have demonstrated the influence of external factors (environmental factors and the coral host factors) on the community structure of coral-associated bacteria. However, the internal factors, e.g. the interaction within the bacterial community or bacteria itself, have often been overlooked in studies of the coral microbiome. Hence, we performed a reciprocal transplant of corals between two different climate zones to examine the resultant alterations in coral-associated bacterial communities. The findings highlight the significance of environmental factors, host selection, and highly resilient bacteria in shaping the coral microbial composition. The results support that coral species consistently harbor specific predominant bacterial groups influenced by host selection, while locations display unique bacterial taxa due to environmental variations. The transplantation of corals into new environments leads to a gradual shift in the bacterial community, from initially resembling that of the native location to eventually resembling that of the transplanted location, emphasizing the crucial role of bacterial community composition for coral survival under changing ambient conditions. Furthermore, highly resilient bacteria that persisted throughout the reciprocal transplant experiment demonstrated their adaptability to environmental and host changes, suggesting the presence of robust adaptation or resistance mechanisms in bacterial communities. Genetic adaptations within the prevalent bacterial group, Endozoicomonas, were also observed, suggesting variations in resilience and adaptation capabilities among different phylotypes. This study highlights the need to conduct further investigations into the coral-associated bacteria themselves, as they may hold some key insights into understanding the dynamics of coral-associated microbial communities. These data also highlight some key species of coral-associated bacteria which could benefit coral in response to alterations in ambient environment.
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Affiliation(s)
- Ya-Fan Chan
- Department of Microbiology, Soochow University, Taipei 111, Taiwan
| | - Yu-Hsiang Chen
- Biodiversity Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Sheng-Ping Yu
- Biodiversity Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Hsing-Ju Chen
- Biodiversity Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Yoko Nozawa
- Biodiversity Research Center, Academia Sinica, Taipei 115, Taiwan
| | - Sen-Lin Tang
- Biodiversity Research Center, Academia Sinica, Taipei 115, Taiwan; Taiwan's Ocean Genome Center, National Taiwan Ocean University, Keelung, Taiwan.
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Dungan AM, Geissler L, Williams AS, Gotze CR, Flynn EC, Blackall LL, van Oppen MJH. DNA from non-viable bacteria biases diversity estimates in the corals Acropora loripes and Pocillopora acuta. ENVIRONMENTAL MICROBIOME 2023; 18:86. [PMID: 38062479 PMCID: PMC10704692 DOI: 10.1186/s40793-023-00541-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 11/23/2023] [Indexed: 06/30/2024]
Abstract
BACKGROUND Nucleic acid-based analytical methods have greatly expanded our understanding of global prokaryotic diversity, yet standard metabarcoding methods provide no information on the most fundamental physiological state of bacteria, viability. Scleractinian corals harbour a complex microbiome in which bacterial symbionts play critical roles in maintaining health and functioning of the holobiont. However, the coral holobiont contains both dead and living bacteria. The former can be the result of corals feeding on bacteria, rapid swings from hyper- to hypoxic conditions in the coral tissue, the presence of antimicrobial compounds in coral mucus, and an abundance of lytic bacteriophages. RESULTS By combining propidium monoazide (PMA) treatment with high-throughput sequencing on six coral species (Acropora loripes, A. millepora, A. kenti, Platygyra daedalea, Pocillopora acuta, and Porites lutea) we were able to obtain information on bacterial communities with little noise from non-viable microbial DNA. Metabarcoding of the 16S rRNA gene showed significantly higher community evenness (85%) and species diversity (31%) in untreated compared with PMA-treated tissue for A. loripes only. While PMA-treated coral did not differ significantly from untreated samples in terms of observed number of ASVs, > 30% of ASVs were identified in untreated samples only, suggesting that they originated from cell-free/non-viable DNA. Further, the bacterial community structure was significantly different between PMA-treated and untreated samples for A. loripes and P. acuta indicating that DNA from non-viable microbes can bias community composition data in coral species with low bacterial diversity. CONCLUSIONS Our study is highly relevant to microbiome studies on coral and other host organisms as it delivers a solution to excluding non-viable DNA in a complex community. These results provide novel insights into the dynamic nature of host-associated microbiomes and underline the importance of applying versatile tools in the analysis of metabarcoding or next-generation sequencing data sets.
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Affiliation(s)
- Ashley M Dungan
- School of BioSciences, University of Melbourne, Melbourne, VIC, Australia.
| | - Laura Geissler
- School of BioSciences, University of Melbourne, Melbourne, VIC, Australia
| | - Amanda S Williams
- School of BioSciences, University of Melbourne, Melbourne, VIC, Australia
| | - Cecilie Ravn Gotze
- School of BioSciences, University of Melbourne, Melbourne, VIC, Australia
- Australian Institute of Marine Science, Townsville, QLD, Australia
| | - Emily C Flynn
- School of BioSciences, University of Melbourne, Melbourne, VIC, Australia
| | - Linda L Blackall
- School of BioSciences, University of Melbourne, Melbourne, VIC, Australia
| | - Madeleine J H van Oppen
- School of BioSciences, University of Melbourne, Melbourne, VIC, Australia
- Australian Institute of Marine Science, Townsville, QLD, Australia
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Li J, Zou Y, Li Q, Zhang J, Bourne DG, Lyu Y, Liu C, Zhang S. A coral-associated actinobacterium mitigates coral bleaching under heat stress. ENVIRONMENTAL MICROBIOME 2023; 18:83. [PMID: 37996910 PMCID: PMC10668361 DOI: 10.1186/s40793-023-00540-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 11/16/2023] [Indexed: 11/25/2023]
Abstract
BACKGROUND The positive effects of exposing corals to microorganisms have been reported though how the benefits are conferred are poorly understood. Here, we isolated an actinobacterial strain (SCSIO 13291) from Pocillopora damicornis with capabilities to synthesize antioxidants, vitamins, and antibacterial and antiviral compounds supported with phenotypic and/or genomic evidence. Strain SCSIO 13291 was labeled with 5 (and - 6)-carboxytetramethylrhodamine, succinimidyl ester and the labeled cell suspension directly inoculated onto the coral polyp tissues when nubbins were under thermal stress in a mesocosm experiment. We then visualized the labelled bacterial cells and analyzed the coral physiological, transcriptome and microbiome to elucidate the effect this strain conferred on the coral holobiont under thermal stress. RESULTS Subsequent microscopic observations confirmed the presence of the bacterium attached to the coral polyps. Addition of the SCSIO 13291 strain reduced signs of bleaching in the corals subjected to heat stress. At the same time, alterations in gene expression, which were involved in reactive oxygen species and light damage mitigation, attenuated apoptosis and exocytosis in addition to metabolite utilization, were observed in the coral host and Symbiodiniaceae populations. In addition, the coral associated bacterial community altered with a more stable ecological network for samples inoculated with the bacterial strain. CONCLUSIONS Our results provide insights into the benefits of a putative actinobacterial probiotic strain that mitigate coral bleaching signs. This study suggests that the inoculation of bacteria can potentially directly benefit the coral holobiont through conferring metabolic activities or through indirect mechanisms of suppling additional nutrient sources.
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Affiliation(s)
- Jie Li
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong, China.
- Sanya National Marine Ecosystem Research Station, Chinese Academy of Sciences, Sanya, Hainan, China.
| | - Yiyang Zou
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong, China
| | - Qiqi Li
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong, China
| | - Jian Zhang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong, China
| | - David G Bourne
- College of Science and Engineering, James Cook University, Townsville, QLD, Australia
- Australian Institute of Marine Science, Townsville, QLD, Australia
| | - Yuanjiao Lyu
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong, China
| | - Cong Liu
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong, China
| | - Si Zhang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong, China
- Sanya National Marine Ecosystem Research Station, Chinese Academy of Sciences, Sanya, Hainan, China
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Hawthorn A, Berzins IK, Dennis MM, Kiupel M, Newton AL, Peters EC, Reyes VA, Work TM. An introduction to lesions and histology of scleractinian corals. Vet Pathol 2023; 60:529-546. [PMID: 37519147 DOI: 10.1177/03009858231189289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/01/2023]
Abstract
Stony corals (Scleractinia) are in the Phylum Cnidaria (cnidae referring to various types of stinging cells). They may be solitary or colonial, but all secrete an external, supporting aragonite skeleton. Large, colonial members of this phylum are responsible for the accretion of coral reefs in tropical and subtropical waters that form the foundations of the most biodiverse marine ecosystems. Coral reefs worldwide, but particularly in the Caribbean, are experiencing unprecedented levels of disease, resulting in reef degradation. Most coral diseases remain poorly described and lack clear case definitions, while the etiologies and pathogenesis are even more elusive. This introductory guide is focused on reef-building corals and describes basic gross and microscopic lesions in these corals in order to serve as an invitation to other veterinary pathologists to play a critical role in defining and advancing the field of coral pathology.
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Affiliation(s)
- Aine Hawthorn
- University of Wisconsin-Madison, Madison, WI
- U.S. Geological Survey, Seattle, WA
| | - Ilze K Berzins
- University of Florida, Gainesville, FL
- One Water, One Health, LLC, Golden Valley, MN
| | | | | | - Alisa L Newton
- ZooQuatic Laboratory, LLC, Baltimore, MD
- OCEARCH, Park City, UT
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Maire J, Tandon K, Collingro A, van de Meene A, Damjanovic K, Gotze CR, Stephenson S, Philip GK, Horn M, Cantin NE, Blackall LL, van Oppen MJH. Colocalization and potential interactions of Endozoicomonas and chlamydiae in microbial aggregates of the coral Pocillopora acuta. SCIENCE ADVANCES 2023; 9:eadg0773. [PMID: 37196086 DOI: 10.1126/sciadv.adg0773] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 04/13/2023] [Indexed: 05/19/2023]
Abstract
Corals are associated with a variety of bacteria, which occur in the surface mucus layer, gastrovascular cavity, skeleton, and tissues. Some tissue-associated bacteria form clusters, termed cell-associated microbial aggregates (CAMAs), which are poorly studied. Here, we provide a comprehensive characterization of CAMAs in the coral Pocillopora acuta. Combining imaging techniques, laser capture microdissection, and amplicon and metagenome sequencing, we show that (i) CAMAs are located in the tentacle tips and may be intracellular; (ii) CAMAs contain Endozoicomonas (Gammaproteobacteria) and Simkania (Chlamydiota) bacteria; (iii) Endozoicomonas may provide vitamins to its host and use secretion systems and/or pili for colonization and aggregation; (iv) Endozoicomonas and Simkania occur in distinct, but adjacent, CAMAs; and (v) Simkania may receive acetate and heme from neighboring Endozoicomonas. Our study provides detailed insight into coral endosymbionts, thereby improving our understanding of coral physiology and health and providing important knowledge for coral reef conservation in the climate change era.
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Affiliation(s)
- Justin Maire
- School of BioSciences, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Kshitij Tandon
- School of BioSciences, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Astrid Collingro
- Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna 1030, Austria
| | - Allison van de Meene
- School of BioSciences, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Katarina Damjanovic
- Australian Institute of Marine Science, PMB No 3, Townsville, QLD 4810, Australia
| | - Cecilie Ravn Gotze
- School of BioSciences, The University of Melbourne, Parkville, VIC 3010, Australia
- Australian Institute of Marine Science, PMB No 3, Townsville, QLD 4810, Australia
| | - Sophie Stephenson
- Australian Institute of Marine Science, PMB No 3, Townsville, QLD 4810, Australia
| | - Gayle K Philip
- Melbourne Bioinformatics, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Matthias Horn
- Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna 1030, Austria
| | - Neal E Cantin
- Australian Institute of Marine Science, PMB No 3, Townsville, QLD 4810, Australia
| | - Linda L Blackall
- School of BioSciences, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Madeleine J H van Oppen
- School of BioSciences, The University of Melbourne, Parkville, VIC 3010, Australia
- Australian Institute of Marine Science, PMB No 3, Townsville, QLD 4810, Australia
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Wada N, Hsu MT, Tandon K, Hsiao SSY, Chen HJ, Chen YH, Chiang PW, Yu SP, Lu CY, Chiou YJ, Tu YC, Tian X, Chen BC, Lee DC, Yamashiro H, Bourne DG, Tang SL. High-resolution spatial and genomic characterization of coral-associated microbial aggregates in the coral Stylophora pistillata. SCIENCE ADVANCES 2022; 8:eabo2431. [PMID: 35857470 PMCID: PMC9258956 DOI: 10.1126/sciadv.abo2431] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 05/13/2022] [Indexed: 05/29/2023]
Abstract
Bacteria commonly form aggregates in a range of coral species [termed coral-associated microbial aggregates (CAMAs)], although these structures remain poorly characterized despite extensive efforts studying the coral microbiome. Here, we comprehensively characterize CAMAs associated with Stylophora pistillata and quantify their cell abundance. Our analysis reveals that multiple Endozoicomonas phylotypes coexist inside a single CAMA. Nanoscale secondary ion mass spectrometry imaging revealed that the Endozoicomonas cells were enriched with phosphorus, with the elemental compositions of CAMAs different from coral tissues and endosymbiotic Symbiodiniaceae, highlighting a role in sequestering and cycling phosphate between coral holobiont partners. Consensus metagenome-assembled genomes of the two dominant Endozoicomonas phylotypes confirmed their metabolic potential for polyphosphate accumulation along with genomic signatures including type VI secretion systems allowing host association. Our findings provide unprecedented insights into Endozoicomonas-dominated CAMAs and the first direct physiological and genomic linked evidence of their biological role in the coral holobiont.
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Affiliation(s)
- Naohisa Wada
- Biodiversity Research Center, Academia Sinica, No. 128, Section 2, Academia Rd., Nangang, Taipei 11529, Taiwan
| | - Ming-Tsung Hsu
- Biodiversity Research Center, Academia Sinica, No. 128, Section 2, Academia Rd., Nangang, Taipei 11529, Taiwan
| | - Kshitij Tandon
- Biodiversity Research Center, Academia Sinica, No. 128, Section 2, Academia Rd., Nangang, Taipei 11529, Taiwan
| | - Silver Sung-Yun Hsiao
- Institute of Astronomy and Astrophysics, Academia Sinica, No. 128, Section 2, Academia Rd., Nangang, Taipei 11529, Taiwan
| | - Hsing-Ju Chen
- Biodiversity Research Center, Academia Sinica, No. 128, Section 2, Academia Rd., Nangang, Taipei 11529, Taiwan
| | - Yu-Hsiang Chen
- Biodiversity Research Center, Academia Sinica, No. 128, Section 2, Academia Rd., Nangang, Taipei 11529, Taiwan
| | - Pei-Wen Chiang
- Biodiversity Research Center, Academia Sinica, No. 128, Section 2, Academia Rd., Nangang, Taipei 11529, Taiwan
| | - Sheng-Ping Yu
- Biodiversity Research Center, Academia Sinica, No. 128, Section 2, Academia Rd., Nangang, Taipei 11529, Taiwan
| | - Chih-Ying Lu
- Biodiversity Research Center, Academia Sinica, No. 128, Section 2, Academia Rd., Nangang, Taipei 11529, Taiwan
- Molecular and Biological Agricultural Sciences Program, Taiwan International Graduate Program, National Chung Hsing University and Academia Sinica, Taipei 11529, Taiwan
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung 40227, Taiwan
| | - Yu-Jing Chiou
- Biodiversity Research Center, Academia Sinica, No. 128, Section 2, Academia Rd., Nangang, Taipei 11529, Taiwan
| | - Yung-Chi Tu
- Biodiversity Research Center, Academia Sinica, No. 128, Section 2, Academia Rd., Nangang, Taipei 11529, Taiwan
| | - Xuejiao Tian
- Research Center for Applied Sciences, Academia Sinica, No. 128, Section 2, Academia Rd., Nangang, Taipei 11529, Taiwan
| | - Bi-Chang Chen
- Research Center for Applied Sciences, Academia Sinica, No. 128, Section 2, Academia Rd., Nangang, Taipei 11529, Taiwan
| | - Der-Chuen Lee
- Institute of Earth Sciences, Academia Sinica, No. 128, Section 2, Academia Rd., Nangang, Taipei 11529, Taiwan
| | - Hideyuki Yamashiro
- Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, 3422 Sesoko, Motobu, Okinawa 905-0227, Japan
| | - David G. Bourne
- College of Science and Engineering, James Cook University, Townsville, 4811 QLD, Australia
- Australian Institute of Marine Science, Townsville, 4810 QLD, Australia
- AIMS@JCU, Townsville, 4811 QLD, Australia
| | - Sen-Lin Tang
- Biodiversity Research Center, Academia Sinica, No. 128, Section 2, Academia Rd., Nangang, Taipei 11529, Taiwan
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10
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Godefroid M, Hédouin L, Mercière A, Dubois P. Thermal stress responses of the antipatharian Stichopathes sp. from the mesophotic reef of Mo'orea, French Polynesia. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 820:153094. [PMID: 35051469 DOI: 10.1016/j.scitotenv.2022.153094] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 12/22/2021] [Accepted: 01/09/2022] [Indexed: 06/14/2023]
Abstract
Antipatharians, also called black corals, are present in almost all oceans of the world, until extreme depths. In several regions, they aggregate in higher densities to form black coral beds that support diverse animal communities and create biodiversity hotspots. These recently discovered ecosystems are currently threatened by fishing activities and illegal harvesting for commercial purposes. Despite this, studies dedicated to the physiology of antipatharians are scarce and their responses to global change stressors have remained hardly explored since recently. Here, we present the first study on the physiological responses of a mesophotic antipatharian Stichopathes sp. (70-90 m) to thermal stress through a 16-d laboratory exposure (from 26 to 30.5 °C). Oxygen consumption measurements allowed identifying the physiological tipping point of Stichopathes sp. (Topt = 28.3 °C; 2.7 °C above mean ambient condition). Our results follow theoretical predictions as performances start to decrease beyond Topt, with lowered oxygen consumption rates, impairment of the healing capacities, increased probability of tissue necrosis and stress responses activated as a function of temperature (i.e. increase in mucocyte density and total antioxidant capacity). Altogether, our work indicates that Stichopathes sp. lives at suboptimal performances during the coldest months of the year, but also that it is likely to have low acclimatization capacity and a narrow thermal breadth.
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Affiliation(s)
- Mathilde Godefroid
- Laboratoire de Biologie marine, Université Libre de Bruxelles, Avenue F.D. Roosevelt 50, CP160/15, 1050 Bruxelles, Belgium.
| | - Laetitia Hédouin
- PSL Research University: EPHE-CNRS-UPVD, USR 3278 CRIOBE, BP 1013, 98729 Papetoai, Mo'orea, French Polynesia; Laboratoire d'Excellence « CORAIL», Mo'orea, French Polynesia
| | - Alexandre Mercière
- PSL Research University: EPHE-CNRS-UPVD, USR 3278 CRIOBE, BP 1013, 98729 Papetoai, Mo'orea, French Polynesia; Laboratoire d'Excellence « CORAIL», Mo'orea, French Polynesia
| | - Philippe Dubois
- Laboratoire de Biologie marine, Université Libre de Bruxelles, Avenue F.D. Roosevelt 50, CP160/15, 1050 Bruxelles, Belgium
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11
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Rädecker N, Pogoreutz C, Gegner HM, Cárdenas A, Perna G, Geißler L, Roth F, Bougoure J, Guagliardo P, Struck U, Wild C, Pernice M, Raina JB, Meibom A, Voolstra CR. Heat stress reduces the contribution of diazotrophs to coral holobiont nitrogen cycling. THE ISME JOURNAL 2021; 16:1110-1118. [PMID: 34857934 PMCID: PMC8941099 DOI: 10.1038/s41396-021-01158-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 11/11/2021] [Accepted: 11/16/2021] [Indexed: 12/22/2022]
Abstract
Efficient nutrient cycling in the coral-algal symbiosis requires constant but limited nitrogen availability. Coral-associated diazotrophs, i.e., prokaryotes capable of fixing dinitrogen, may thus support productivity in a stable coral-algal symbiosis but could contribute to its breakdown when overstimulated. However, the effects of environmental conditions on diazotroph communities and their interaction with other members of the coral holobiont remain poorly understood. Here we assessed the effects of heat stress on diazotroph diversity and their contribution to holobiont nutrient cycling in the reef-building coral Stylophora pistillata from the central Red Sea. In a stable symbiotic state, we found that nitrogen fixation by coral-associated diazotrophs constitutes a source of nitrogen to the algal symbionts. Heat stress caused an increase in nitrogen fixation concomitant with a change in diazotroph communities. Yet, this additional fixed nitrogen was not assimilated by the coral tissue or the algal symbionts. We conclude that although diazotrophs may support coral holobiont functioning under low nitrogen availability, altered nutrient cycling during heat stress abates the dependence of the coral host and its algal symbionts on diazotroph-derived nitrogen. Consequently, the role of nitrogen fixation in the coral holobiont is strongly dependent on its nutritional status and varies dynamically with environmental conditions.
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Affiliation(s)
- Nils Rädecker
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia. .,Department of Biology, University of Konstanz, Konstanz, Germany. .,Laboratory for Biological Geochemistry, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
| | - Claudia Pogoreutz
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia.,Department of Biology, University of Konstanz, Konstanz, Germany
| | - Hagen M Gegner
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia.,Metabolomics Core Technology Platform, Centre for Organismal Studies, University of Heidelberg, Heidelberg, Germany
| | - Anny Cárdenas
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia.,Department of Biology, University of Konstanz, Konstanz, Germany
| | - Gabriela Perna
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia.,Department of Biology, University of Konstanz, Konstanz, Germany
| | - Laura Geißler
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Florian Roth
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia.,Baltic Sea Centre, Stockholm University, Stockholm, Sweden.,Faculty of Biological and Environmental Sciences, Tvärminne Zoological Station, University of Helsinki, Helsinki, Finland
| | - Jeremy Bougoure
- Centre for Microscopy, Characterisation and Analysis, University of Western Australia, Perth, WA, Australia
| | - Paul Guagliardo
- Centre for Microscopy, Characterisation and Analysis, University of Western Australia, Perth, WA, Australia
| | - Ulrich Struck
- Museum für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, Berlin, Germany.,Department of Earth Sciences, Freie Universität Berlin, Berlin, Germany
| | - Christian Wild
- Faculty of Biology and Chemistry, Marine Ecology Department, University of Bremen, Bremen, Germany
| | - Mathieu Pernice
- Climate Change Cluster, University of Technology Sydney, Sydney, NSW, Australia
| | - Jean-Baptiste Raina
- Climate Change Cluster, University of Technology Sydney, Sydney, NSW, Australia
| | - Anders Meibom
- Laboratory for Biological Geochemistry, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.,Center for Advanced Surface Analysis, Institute of Earth Sciences, Université de Lausanne, Lausanne, Switzerland
| | - Christian R Voolstra
- Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia.,Department of Biology, University of Konstanz, Konstanz, Germany
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12
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Thatcher C, Høj L, Bourne DG. Probiotics for coral aquaculture: challenges and considerations. Curr Opin Biotechnol 2021; 73:380-386. [PMID: 34749049 DOI: 10.1016/j.copbio.2021.09.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 09/18/2021] [Accepted: 09/21/2021] [Indexed: 01/12/2023]
Abstract
Globally, coral reefs are under pressure from climate change, with concerning declines in coral abundance observed due to increasing cumulative impacts. Active intervention measures that mitigate the declines are increasingly being applied to buy time for coral reefs as the world transitions to a low-carbon economy. One such mitigation strategy is coral restoration based on large-scale coral aquaculture to provide stock for reseeding reefs, with the added potential of selecting corals that better tolerate environmental stress. Application of probiotics during production and deployment, to modulate the naturally occurring bacteria associated with corals, may confer health benefits such as disease resistance, increased environmental tolerance or improved coral nutrition. Here, we briefly describe coral associated bacteria and their role in the coral holobiont, identify probiotics traits potentially beneficial to coral, and discuss current research directions required to develop, test and verify the feasibility for probiotics to improve coral aquaculture at industrial scales.
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Affiliation(s)
- Callaway Thatcher
- College of Science and Engineering, James Cook University, 1 Angus Smith Drive, Douglas, QLD 4814, Australia; Australian Institute of Marine Science, PMB 3 Townsville MC, Townsville, QLD 4810, Australia; AIMS@JCU, James Cook University, DB17-148, Townsville, QLD 4811, Australia
| | - Lone Høj
- Australian Institute of Marine Science, PMB 3 Townsville MC, Townsville, QLD 4810, Australia; AIMS@JCU, James Cook University, DB17-148, Townsville, QLD 4811, Australia
| | - David G Bourne
- College of Science and Engineering, James Cook University, 1 Angus Smith Drive, Douglas, QLD 4814, Australia; Australian Institute of Marine Science, PMB 3 Townsville MC, Townsville, QLD 4810, Australia; AIMS@JCU, James Cook University, DB17-148, Townsville, QLD 4811, Australia.
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13
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Maire J, Blackall LL, van Oppen MJH. Intracellular Bacterial Symbionts in Corals: Challenges and Future Directions. Microorganisms 2021; 9:2209. [PMID: 34835335 PMCID: PMC8619543 DOI: 10.3390/microorganisms9112209] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 10/21/2021] [Accepted: 10/21/2021] [Indexed: 02/07/2023] Open
Abstract
Corals are the main primary producers of coral reefs and build the three-dimensional reef structure that provides habitat to more than 25% of all marine eukaryotes. They harbor a complex consortium of microorganisms, including bacteria, archaea, fungi, viruses, and protists, which they rely on for their survival. The symbiosis between corals and bacteria is poorly studied, and their symbiotic relationships with intracellular bacteria are only just beginning to be acknowledged. In this review, we emphasize the importance of characterizing intracellular bacteria associated with corals and explore how successful approaches used to study such microorganisms in other systems could be adapted for research on corals. We propose a framework for the description, identification, and functional characterization of coral-associated intracellular bacterial symbionts. Finally, we highlight the possible value of intracellular bacteria in microbiome manipulation and mitigating coral bleaching.
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Affiliation(s)
- Justin Maire
- School of Biosciences, The University of Melbourne, Melbourne, VIC 3010, Australia; (L.L.B.); (M.J.H.v.O.)
| | - Linda L. Blackall
- School of Biosciences, The University of Melbourne, Melbourne, VIC 3010, Australia; (L.L.B.); (M.J.H.v.O.)
| | - Madeleine J. H. van Oppen
- School of Biosciences, The University of Melbourne, Melbourne, VIC 3010, Australia; (L.L.B.); (M.J.H.v.O.)
- Australian Institute of Marine Science, Townsville, QLD 4810, Australia
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14
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Peixoto RS, Sweet M, Villela HDM, Cardoso P, Thomas T, Voolstra CR, Høj L, Bourne DG. Coral Probiotics: Premise, Promise, Prospects. Annu Rev Anim Biosci 2020; 9:265-288. [PMID: 33321044 DOI: 10.1146/annurev-animal-090120-115444] [Citation(s) in RCA: 76] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The use of Beneficial Microorganisms for Corals (BMCs) has been proposed recently as a tool for the improvement of coral health, with knowledge in this research topic advancing rapidly. BMCs are defined as consortia of microorganisms that contribute to coral health through mechanisms that include (a) promoting coral nutrition and growth, (b) mitigating stress and impacts of toxic compounds, (c) deterring pathogens, and (d) benefiting early life-stage development. Here, we review the current proposed BMC approach and outline the studies that have proven its potential to increase coral resilience to stress. We revisit and expand the list of putative beneficial microorganisms associated with corals and their proposed mechanismsthat facilitate improved host performance. Further, we discuss the caveats and bottlenecks affecting the efficacy of BMCs and close by focusing on the next steps to facilitate application at larger scales that can improve outcomes for corals and reefs globally.
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Affiliation(s)
- Raquel S Peixoto
- Laboratory of Molecular Microbial Ecology, Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro, Rio de Janeiro 21941-901, Brazil; .,IMAM-AquaRio, Rio de Janeiro Aquarium Research Center, Rio de Janeiro, 20220-360, Brazil.,Current affiliation: Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
| | - Michael Sweet
- Aquatic Research Facility, Environmental Sustainability Research Centre, University of Derby, Derby DE22 1GB, United Kingdom
| | - Helena D M Villela
- Laboratory of Molecular Microbial Ecology, Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro, Rio de Janeiro 21941-901, Brazil;
| | - Pedro Cardoso
- Laboratory of Molecular Microbial Ecology, Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro, Rio de Janeiro 21941-901, Brazil;
| | - Torsten Thomas
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Christian R Voolstra
- Department of Biology, University of Konstanz, Konstanz 78457, Germany.,Division of Biological and Environmental Science and Engineering, Red Sea Research Center, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
| | - Lone Høj
- Australian Institute of Marine Science, Townsville, Queensland 4810, Australia
| | - David G Bourne
- Australian Institute of Marine Science, Townsville, Queensland 4810, Australia.,College of Science and Engineering, James Cook University, Townsville, Queensland 4811, Australia
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15
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Energy depletion and opportunistic microbial colonisation in white syndrome lesions from corals across the Indo-Pacific. Sci Rep 2020; 10:19990. [PMID: 33203914 PMCID: PMC7672225 DOI: 10.1038/s41598-020-76792-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 10/30/2020] [Indexed: 12/28/2022] Open
Abstract
Corals are dependent upon lipids as energy reserves to mount a metabolic response to biotic and abiotic challenges. This study profiled lipids, fatty acids, and microbial communities of healthy and white syndrome (WS) diseased colonies of Acropora hyacinthus sampled from reefs in Western Australia, the Great Barrier Reef, and Palmyra Atoll. Total lipid levels varied significantly among locations, though a consistent stepwise decrease from healthy tissues from healthy colonies (HH) to healthy tissue on WS-diseased colonies (HD; i.e. preceding the lesion boundary) to diseased tissue on diseased colonies (DD; i.e. lesion front) was observed, demonstrating a reduction in energy reserves. Lipids in HH tissues were comprised of high energy lipid classes, while HD and DD tissues contained greater proportions of structural lipids. Bacterial profiling through 16S rRNA gene sequencing and histology showed no bacterial taxa linked to WS causation. However, the relative abundance of Rhodobacteraceae-affiliated sequences increased in DD tissues, suggesting opportunistic proliferation of these taxa. While the cause of WS remains inconclusive, this study demonstrates that the lipid profiles of HD tissues was more similar to DD tissues than to HH tissues, reflecting a colony-wide systemic effect and provides insight into the metabolic immune response of WS-infected Indo-Pacific corals.
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16
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Boilard A, Dubé CE, Gruet C, Mercière A, Hernandez-Agreda A, Derome N. Defining Coral Bleaching as a Microbial Dysbiosis within the Coral Holobiont. Microorganisms 2020; 8:microorganisms8111682. [PMID: 33138319 PMCID: PMC7692791 DOI: 10.3390/microorganisms8111682] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 10/26/2020] [Accepted: 10/28/2020] [Indexed: 12/11/2022] Open
Abstract
Coral microbiomes are critical to holobiont health and functioning, but the stability of host–microbial interactions is fragile, easily shifting from eubiosis to dysbiosis. The heat-induced breakdown of the symbiosis between the host and its dinoflagellate algae (that is, “bleaching”), is one of the most devastating outcomes for reef ecosystems. Yet, bleaching tolerance has been observed in some coral species. This review provides an overview of the holobiont’s diversity, explores coral thermal tolerance in relation to their associated microorganisms, discusses the hypothesis of adaptive dysbiosis as a mechanism of environmental adaptation, mentions potential solutions to mitigate bleaching, and suggests new research avenues. More specifically, we define coral bleaching as the succession of three holobiont stages, where the microbiota can (i) maintain essential functions for holobiont homeostasis during stress and/or (ii) act as a buffer to mitigate bleaching by favoring the recruitment of thermally tolerant Symbiodiniaceae species (adaptive dysbiosis), and where (iii) environmental stressors exceed the buffering capacity of both microbial and dinoflagellate partners leading to coral death.
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Affiliation(s)
- Aurélie Boilard
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec City, QC G1V 0A6, Canada; (A.B.); (C.G.)
| | - Caroline E. Dubé
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec City, QC G1V 0A6, Canada; (A.B.); (C.G.)
- California Academy of Sciences, 55 Music Concourse Drive, San Francisco, CA 94118, USA;
- Correspondence: (C.E.D.); (N.D.)
| | - Cécile Gruet
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec City, QC G1V 0A6, Canada; (A.B.); (C.G.)
| | - Alexandre Mercière
- PSL Research University: EPHE-UPVD-CNRS, USR 3278 CRIOBE, Université de Perpignan, 66860 Perpignan CEDEX, France;
- Laboratoire d’Excellence “CORAIL”, 98729 Papetoai, Moorea, French Polynesia
| | | | - Nicolas Derome
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec City, QC G1V 0A6, Canada; (A.B.); (C.G.)
- Département de Biologie, Faculté des Sciences et de Génie, Université Laval, Québec City, QC G1V 0A6, Canada
- Correspondence: (C.E.D.); (N.D.)
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17
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Marchioro GM, Glasl B, Engelen AH, Serrão EA, Bourne DG, Webster NS, Frade PR. Microbiome dynamics in the tissue and mucus of acroporid corals differ in relation to host and environmental parameters. PeerJ 2020; 8:e9644. [PMID: 32874778 PMCID: PMC7439960 DOI: 10.7717/peerj.9644] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 07/10/2020] [Indexed: 12/19/2022] Open
Abstract
Corals are associated with diverse microbial assemblages; however, the spatial-temporal dynamics of intra-species microbial interactions are poorly understood. The coral-associated microbial community varies substantially between tissue and mucus microhabitats; however, the factors controlling the occurrence, abundance, and distribution of microbial taxa over time have rarely been explored for different coral compartments simultaneously. Here, we test (1) differentiation in microbiome diversity and composition between coral compartments (surface mucus and tissue) of two Acropora hosts (A. tenuis and A. millepora) common along inshore reefs of the Great Barrier Reef, as well as (2) the potential linkage between shifts in individual coral microbiome families and underlying host and environmental parameters. Amplicon based 16S ribosomal RNA gene sequencing of 136 samples collected over 14 months, revealed significant differences in bacterial richness, diversity and community structure among mucus, tissue and the surrounding seawater. Seawater samples were dominated by members of the Synechococcaceae and Pelagibacteraceae bacterial families. The mucus microbiome of Acropora spp. was dominated by members of Flavobacteriaceae, Synechococcaceae and Rhodobacteraceae and the tissue was dominated by Endozoicimonaceae. Mucus microbiome in both Acropora species was primarily correlated with seawater parameters including levels of chlorophyll a, ammonium, particulate organic carbon and the sum of nitrate and nitrite. In contrast, the correlation of the tissue microbiome to the measured environmental (i.e., seawater parameters) and host health physiological factors differed between host species, suggesting host-specific modulation of the tissue-associated microbiome to intrinsic and extrinsic factors. Furthermore, the correlation between individual coral microbiome members and environmental factors provides novel insights into coral microbiome-by-environment dynamics and hence has potential implications for current reef restoration and management efforts (e.g. microbial monitoring and observatory programs).
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Affiliation(s)
- Giulia M Marchioro
- University of Algarve, Faro, Portugal.,CCMAR - Centre of Marine Sciences, University of Algarve, Faro, Portugal.,AIMS@JCU, Townsville, Queensland, Australia
| | - Bettina Glasl
- AIMS@JCU, Townsville, Queensland, Australia.,Australian Institute of Marine Science, Townsville, Queensland, Australia.,College of Science and Engineering, James Cook University, Queensland, Townsville, Australia
| | - Aschwin H Engelen
- CCMAR - Centre of Marine Sciences, University of Algarve, Faro, Portugal
| | - Ester A Serrão
- CCMAR - Centre of Marine Sciences, University of Algarve, Faro, Portugal
| | - David G Bourne
- AIMS@JCU, Townsville, Queensland, Australia.,Australian Institute of Marine Science, Townsville, Queensland, Australia.,College of Science and Engineering, James Cook University, Queensland, Townsville, Australia
| | - Nicole S Webster
- AIMS@JCU, Townsville, Queensland, Australia.,Australian Institute of Marine Science, Townsville, Queensland, Australia.,Australian Centre for Ecogenomics, University of Queensland, Brisbane, Queensland, Australia
| | - Pedro R Frade
- CCMAR - Centre of Marine Sciences, University of Algarve, Faro, Portugal
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18
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Vanwonterghem I, Webster NS. Coral Reef Microorganisms in a Changing Climate. iScience 2020; 23:100972. [PMID: 32208346 PMCID: PMC7096749 DOI: 10.1016/j.isci.2020.100972] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 02/24/2020] [Accepted: 03/05/2020] [Indexed: 01/09/2023] Open
Abstract
Coral reefs are one of the most diverse and productive ecosystems on the planet, yet they have suffered tremendous losses due to anthropogenic disturbances and are predicted to be one of the most adversely affected habitats under future climate change conditions. Coral reefs can be viewed as microbially driven ecosystems that rely on the efficient capture, retention, and recycling of nutrients in order to thrive in oligotrophic waters. Microorganisms play vital roles in maintaining holobiont health and ecosystem resilience under environmental stress; however, they are also key players in positive feedback loops that intensify coral reef decline, with cascading effects on biogeochemical cycles and marine food webs. There is an urgent need to develop a fundamental understanding of the complex microbial interactions within coral reefs and their role in ecosystem acclimatization, and it is important to include microorganisms in reef conservation in order to secure a future for these unique environments.
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Affiliation(s)
- Inka Vanwonterghem
- Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, QLD 4072, Australia.
| | - Nicole S Webster
- Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, QLD 4072, Australia; Australian Institute of Marine Science, Townsville, QLD 4810, Australia
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19
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Quigley KM, Alvarez Roa C, Torda G, Bourne DG, Willis BL. Co-dynamics of Symbiodiniaceae and bacterial populations during the first year of symbiosis with Acropora tenuis juveniles. Microbiologyopen 2019; 9:e959. [PMID: 31670480 PMCID: PMC7002099 DOI: 10.1002/mbo3.959] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Revised: 10/04/2019] [Accepted: 10/08/2019] [Indexed: 02/04/2023] Open
Abstract
Interactions between corals and their associated microbial communities (Symbiodiniaceae and prokaryotes) are key to understanding corals' potential for and rate of acclimatory and adaptive responses. However, the establishment of microalgal and bacterial communities is poorly understood during coral ontogeny in the wild. We examined the establishment and co-occurrence between multiple microbial communities using 16S rRNA (bacterial) and ITS2 rDNA (Symbiodiniaceae) gene amplicon sequencing in juveniles of the common coral, Acropora tenuis, across the first year of development. Symbiodiniaceae communities in juveniles were dominated by Durusdinium trenchii and glynnii (D1 and D1a), with lower abundances of Cladocopium (C1, C1d, C50, and Cspc). Bacterial communities were more diverse and dominated by taxa within Proteobacteria, Cyanobacteria, and Planctomycetes. Both communities were characterized by significant changes in relative abundance and diversity of taxa throughout the year. D1, D1a, and C1 were significantly correlated with multiple bacterial taxa, including Alpha-, Deltra-, and Gammaproteobacteria, Planctomycetacia, Oxyphotobacteria, Phycisphaerae, and Rhizobiales. Specifically, D1a tended to associate with Oxyphotobacteria and D1 with Alphaproteobacteria, although these associations may represent correlational and not causal relationships. Bioenergetic modeling combined with physiological measurements of coral juveniles (surface area and Symbiodiniaceae cell densities) identified key periods of carbon limitation and nitrogen assimilation, potentially coinciding with shifts in microbial community composition. These results demonstrate that Symbiodiniaceae and bacterial communities are dynamic throughout the first year of ontology and may vary in tandem, with important fitness effects on host juveniles.
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Affiliation(s)
- Kate M Quigley
- College of Marine and Environmental Sciences, James Cook University, Townsville, QLD, Australia.,AIMS@JCU, Australian Institute of Marine Science and James Cook University, Townsville, QLD, Australia.,Australian Institute of Marine Science, Townsville, QLD, Australia
| | | | - Greg Torda
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD, Australia
| | - David G Bourne
- College of Marine and Environmental Sciences, James Cook University, Townsville, QLD, Australia.,AIMS@JCU, Australian Institute of Marine Science and James Cook University, Townsville, QLD, Australia.,Australian Institute of Marine Science, Townsville, QLD, Australia
| | - Bette L Willis
- College of Marine and Environmental Sciences, James Cook University, Townsville, QLD, Australia.,AIMS@JCU, Australian Institute of Marine Science and James Cook University, Townsville, QLD, Australia.,ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD, Australia
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