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Ju H, Zhang J, Zou Y, Xie F, Tang X, Zhang S, Li J. Bacteria undergo significant shifts while archaea maintain stability in Pocillopora damicornis under sustained heat stress. ENVIRONMENTAL RESEARCH 2024; 250:118469. [PMID: 38354884 DOI: 10.1016/j.envres.2024.118469] [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: 09/17/2023] [Revised: 02/05/2024] [Accepted: 02/10/2024] [Indexed: 02/16/2024]
Abstract
Global warming reportedly poses a critical risk to coral reef ecosystems. Bacteria and archaea are crucial components of the coral holobiont. The response of archaea associated with warming is less well understood than that of the bacterial community in corals. Also, there have been few studies on the dynamics of the microbial community in the coral holobiont under long-term heat stress. In order to track the dynamic alternations in the microbial communities within the heat-stressed coral holobiont, three-week heat-stress monitoring was carried out on the coral Pocillopora damicornis. The findings demonstrate that the corals were stressed at 32 °C, and showed a gradual decrease in Symbiodiniaceae density with increasing duration of heat stress. The archaeal community in the coral holobiont remained relatively unaltered by the increasing temperature, whereas the bacterial community was considerably altered. Sustained heat stress exacerbated the dissimilarities among parallel samples of the bacterial community, confirming the Anna Karenina Principle in animal microbiomes. Heat stress leads to more complex and unstable microbial networks, characterized by an increased average degree and decreased modularity, respectively. With the extension of heat stress duration, the relative abundances of the gene (nifH) and genus (Tistlia) associated with nitrogen fixation increased in coral samples, as well as the potential pathogenic bacteria (Flavobacteriales) and opportunistic bacteria (Bacteroides). Hence, our findings suggest that coral hosts might recruit nitrogen-fixing bacteria during the initial stages of suffering heat stress. An environment that is conducive to the colonization and development of opportunistic and pathogenic bacteria when the coral host becomes more susceptible as heat stress duration increases.
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Affiliation(s)
- Huimin Ju
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jian Zhang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; Sanya National Marine Ecosystem Research Station, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong, China
| | - Yiyang Zou
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China
| | - Feiyang Xie
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China
| | - Xiaoyu Tang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Si Zhang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; Sanya National Marine Ecosystem Research Station, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, China
| | - Jie Li
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; Sanya National Marine Ecosystem Research Station, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong, China.
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2
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Villalobos R, Aylagas E, Ellis JI, Pearman JK, Anlauf H, Curdia J, Lozano-Cortes D, Mejia A, Roth F, Berumen ML, Carvalho S. Responses of the coral reef cryptobiome to environmental gradients in the Red Sea. PLoS One 2024; 19:e0301837. [PMID: 38626123 PMCID: PMC11020721 DOI: 10.1371/journal.pone.0301837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Accepted: 03/24/2024] [Indexed: 04/18/2024] Open
Abstract
An essential component of the coral reef animal diversity is the species hidden in crevices within the reef matrix, referred to as the cryptobiome. These organisms play an important role in nutrient cycling and provide an abundant food source for higher trophic levels, yet they have been largely overlooked. Here, we analyzed the distribution patterns of the mobile cryptobiome (>2000 μm) along the latitudinal gradient of the Saudi Arabian coast of the Red Sea. Analysis was conducted based on 54 Autonomous Reef Monitoring Structures. We retrieved a total of 5273 organisms, from which 2583 DNA sequences from the mitochondrially encoded cytochrome c oxidase I were generated through sanger sequencing. We found that the cryptobiome community is variable over short geographical distances within the basin. Regression tree models identified sea surface temperature (SST), percentage cover of hard coral and turf algae as determinant for the number of operational taxonomic units present per Autonomous Reef Monitoring Structures (ARMS). Our results also show that the community structure of the cryptobiome is associated with the energy available (measured as photosynthetic active radiation), sea surface temperature, and nearby reef habitat characteristics (namely hard corals, turf and macroalgae). Given that temperature and reef benthic characteristics affect the cryptobiome, current scenarios of intensive climate change are likely to modify this fundamental biological component of coral reef functioning. However, the trajectory of change is unknow and can be site specific, as for example, diversity is expected to increase above SST of 28.5°C, and with decreasing hard coral and turf cover. This study provides a baseline of the cryptobenthic community prior to major coastal developments in the Red Sea to be used for future biodiversity studies and monitoring projects. It can also contribute to better understand patterns of reef biodiversity in a period where Marine Protected Areas are being discussed in the region.
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Affiliation(s)
- Rodrigo Villalobos
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal, Saudi Arabia
| | - Eva Aylagas
- The Red Sea Development Company, AlRaidah Digital City, Saudi Arabia
| | - Joanne I. Ellis
- School of Biological Sciences, Waikato University, Tauranga, New Zealand
| | - John K. Pearman
- Coastal and Freshwater Group, Cawthron Institute, Nelson, New Zealand
| | - Holger Anlauf
- University of Seychelles and Blue Economy Research Institute Anse Royal, Victoria, Mahe, Seychelles
| | - Joao Curdia
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal, Saudi Arabia
| | | | - Alejandro Mejia
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal, Saudi Arabia
| | - Florian Roth
- Stockholm University, Baltic Sea Centre, Stockholm, Sweden
| | - Michael L. Berumen
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal, Saudi Arabia
| | - Susana Carvalho
- King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal, Saudi Arabia
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3
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Powell ME, McCoy SJ. Divide and conquer: Spatial and temporal resource partitioning structures benthic cyanobacterial mats. JOURNAL OF PHYCOLOGY 2024; 60:254-272. [PMID: 38467467 DOI: 10.1111/jpy.13443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 02/05/2024] [Accepted: 02/08/2024] [Indexed: 03/13/2024]
Abstract
Benthic cyanobacterial mats are increasing in abundance worldwide with the potential to degrade ecosystem structure and function. Understanding mat community dynamics is thus critical for predicting mat growth and proliferation and for mitigating any associated negative effects. Carbon, nitrogen, and sulfur cycling are the predominant forms of nutrient cycling discussed within the literature, while metabolic cooperation and viral interactions are understudied. Although many forms of nutrient cycling in mats have been assessed, the links between niche dynamics, microbial interactions, and nutrient cycling are not well described. Here, we present an updated review on how nutrient cycling and microbial community interactions in mats are structured by resource partitioning via spatial and temporal heterogeneity and succession. We assess community interactions and nutrient cycling at both intramat and metacommunity scales. Additionally, we present ideas and recommendations for research in this area, highlighting top-down control, boundary layers, and metabolic cooperation as important future directions.
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Affiliation(s)
- Maya E Powell
- Environment, Ecology and Energy Program, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Sophie J McCoy
- Environment, Ecology and Energy Program, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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4
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Vizon C, Urbanowiez A, Raviglione D, Bonnard I, Nugues MM. Benthic cyanobacterial metabolites interact to reduce coral larval survival and settlement. HARMFUL ALGAE 2024; 132:102582. [PMID: 38331546 DOI: 10.1016/j.hal.2024.102582] [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: 09/14/2023] [Revised: 01/04/2024] [Accepted: 01/15/2024] [Indexed: 02/10/2024]
Abstract
Benthic cyanobacterial mats (BCMs) are becoming increasingly abundant on coral reefs worldwide. High growth rates and prolific toxin production give them the potential to cause widespread coral recruitment failure through allelopathic effects, but few studies have made the link between their toxicity for coral larvae and in situ toxin concentrations. Here we investigated the allelopathic effects of the benthic cyanobacterium Anabaena sp.1 on larvae of the coral Pocillopora acuta. This cyanobacterium produces several non-ribosomal cyclic lipopeptides of the laxaphycin family with cytotoxic properties. Therefore, we measured the concentration of laxaphycins A and B in Anabaena mats and in the water column and tested their effects on coral larvae. We found that Anabaena crude extract reduces both larval survivorship and settlement and that laxaphycin B reduces settlement. When larvae were exposed to both laxaphycins, there was a reduction in both larval survival and settlement. In the natural reef environment, laxaphycin A and B concentrations increased with increasing proximity to Anabaena mats, with concentrations being consistently above LC50 and EC50 thresholds within a 1 cm distance of the mats. This study demonstrates that laxaphycins reduce the survival and inhibit the settlement of coral larvae at concentrations found near Anabaena mats in situ. It further shows a combined effect between two cyanobacterial metabolites. As BCMs become more common, more of their secondary metabolites might be released in the water column. Their occurrence will lead to a reduction in coral recruitment rates, contributing to the continuing decline of coral reefs and shift in community structure.
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Affiliation(s)
- Camille Vizon
- PSL Université Paris: EPHE-UPVD-CNRS, UAR 3278 CRIOBE, Université de Perpignan, 52 avenue Paul Alduy, 66860 Perpignan, France.
| | - Axel Urbanowiez
- PSL Université Paris: EPHE-UPVD-CNRS, UAR 3278 CRIOBE, Université de Perpignan, 52 avenue Paul Alduy, 66860 Perpignan, France
| | - Delphine Raviglione
- PSL Université Paris: EPHE-UPVD-CNRS, UAR 3278 CRIOBE, Université de Perpignan, 52 avenue Paul Alduy, 66860 Perpignan, France; Plateau technique MSXM, Plateforme Bio2mar, Université de Perpignan via Domitia, Perpignan, Cedex 9, France
| | - Isabelle Bonnard
- PSL Université Paris: EPHE-UPVD-CNRS, UAR 3278 CRIOBE, Université de Perpignan, 52 avenue Paul Alduy, 66860 Perpignan, France; Plateau technique MSXM, Plateforme Bio2mar, Université de Perpignan via Domitia, Perpignan, Cedex 9, France; Laboratoire d'Excellence Corail, 66860 Perpignan, France
| | - Maggy M Nugues
- PSL Université Paris: EPHE-UPVD-CNRS, UAR 3278 CRIOBE, Université de Perpignan, 52 avenue Paul Alduy, 66860 Perpignan, France; Laboratoire d'Excellence Corail, 66860 Perpignan, France
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5
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Osvatic JT, Yuen B, Kunert M, Wilkins L, Hausmann B, Girguis P, Lundin K, Taylor J, Jospin G, Petersen JM. Gene loss and symbiont switching during adaptation to the deep sea in a globally distributed symbiosis. THE ISME JOURNAL 2023; 17:453-466. [PMID: 36639537 PMCID: PMC9938160 DOI: 10.1038/s41396-022-01355-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 12/16/2022] [Accepted: 12/21/2022] [Indexed: 01/14/2023]
Abstract
Chemosynthetic symbioses between bacteria and invertebrates occur worldwide from coastal sediments to the deep sea. Most host groups are restricted to either shallow or deep waters. In contrast, Lucinidae, the most species-rich family of chemosymbiotic invertebrates, has both shallow- and deep-sea representatives. Multiple lucinid species have independently colonized the deep sea, which provides a unique framework for understanding the role microbial symbionts play in evolutionary transitions between shallow and deep waters. Lucinids acquire their symbionts from their surroundings during early development, which may allow them to flexibly acquire symbionts that are adapted to local environments. Via metagenomic analyses of museum and other samples collected over decades, we investigated the biodiversity and metabolic capabilities of the symbionts of 22 mostly deep-water lucinid species. We aimed to test the theory that the symbiont played a role in adaptation to life in deep-sea habitats. We identified 16 symbiont species, mostly within the previously described genus Ca. Thiodiazotropha. Most genomic functions were shared by both shallow-water and deep-sea Ca. Thiodiazotropha, though nitrogen fixation was exclusive to shallow-water species. We discovered multiple cases of symbiont switching near deep-sea hydrothermal vents and cold seeps, where distantly related hosts convergently acquired novel symbionts from a different bacterial order. Finally, analyses of selection revealed consistently stronger purifying selection on symbiont genomes in two extreme habitats - hydrothermal vents and an oxygen-minimum zone. Our findings reveal that shifts in symbiont metabolic capability and, in some cases, acquisition of a novel symbiont accompanied adaptation of lucinids to challenging deep-sea habitats.
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Affiliation(s)
- Jay T. Osvatic
- grid.10420.370000 0001 2286 1424University of Vienna, Centre for Microbiology and Environmental Systems Science, Department for Microbiology and Ecosystem Science, Division of Microbial Ecology, Djerassiplatz 1, 1030 Vienna, Austria ,University of Venna, Doctoral School in Microbiology and Environmental Science, Djerassiplatz 1, 1030 Vienna, Austria
| | - Benedict Yuen
- grid.10420.370000 0001 2286 1424University of Vienna, Centre for Microbiology and Environmental Systems Science, Department for Microbiology and Ecosystem Science, Division of Microbial Ecology, Djerassiplatz 1, 1030 Vienna, Austria
| | - Martin Kunert
- grid.10420.370000 0001 2286 1424University of Vienna, Centre for Microbiology and Environmental Systems Science, Department for Microbiology and Ecosystem Science, Division of Microbial Ecology, Djerassiplatz 1, 1030 Vienna, Austria
| | - Laetitia Wilkins
- grid.419529.20000 0004 0491 3210Eco-Evolutionary Interactions Group, Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, 28209 Bremen, Germany
| | - Bela Hausmann
- grid.10420.370000 0001 2286 1424Joint Microbiome Facility of the Medical University of Vienna and the University of Vienna, 1030 Vienna, Austria ,grid.22937.3d0000 0000 9259 8492Department of Laboratory Medicine, Medical University of Vienna, 1090 Vienna, Austria
| | - Peter Girguis
- grid.38142.3c000000041936754XDepartment of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138 USA
| | - Kennet Lundin
- grid.516430.50000 0001 0059 3334Gothenburg Natural History Museum, Box 7283, 40235 Gothenburg, Sweden ,grid.8761.80000 0000 9919 9582Gothenburg Global Biodiversity Centre, Box 461, 40530 Gothenburg, Sweden
| | - John Taylor
- grid.35937.3b0000 0001 2270 9879Natural History Museum, Cromwell Rd, London, SW7 5BD UK
| | | | - Jillian M. Petersen
- grid.10420.370000 0001 2286 1424University of Vienna, Centre for Microbiology and Environmental Systems Science, Department for Microbiology and Ecosystem Science, Division of Microbial Ecology, Djerassiplatz 1, 1030 Vienna, Austria
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6
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Nelson CE, Wegley Kelly L, Haas AF. Microbial Interactions with Dissolved Organic Matter Are Central to Coral Reef Ecosystem Function and Resilience. ANNUAL REVIEW OF MARINE SCIENCE 2023; 15:431-460. [PMID: 36100218 DOI: 10.1146/annurev-marine-042121-080917] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
To thrive in nutrient-poor waters, coral reefs must retain and recycle materials efficiently. This review centers microbial processes in facilitating the persistence and stability of coral reefs, specifically the role of these processes in transforming and recycling the dissolved organic matter (DOM) that acts as an invisible currency in reef production, nutrient exchange, and organismal interactions. The defining characteristics of coral reefs, including high productivity, balanced metabolism, high biodiversity, nutrient retention, and structural complexity, are inextricably linked to microbial processing of DOM. The composition of microbes and DOM in reefs is summarized, and the spatial and temporal dynamics of biogeochemical processes carried out by microorganisms in diverse reef habitats are explored in a variety of key reef processes, including decomposition, accretion, trophictransfer, and macronutrient recycling. Finally, we examine how widespread habitat degradation of reefs is altering these important microbe-DOM interactions, creating feedbacks that reduce reef resilience to global change.
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Affiliation(s)
- Craig E Nelson
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education, Department of Oceanography, and Sea Grant College Program, School of Ocean and Earth Sciences and Technology, University of Hawai'i at Mānoa, Honolulu, Hawai'i, USA;
| | - Linda Wegley Kelly
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California, USA;
| | - Andreas F Haas
- Department of Marine Microbiology and Biogeochemistry, Royal Netherlands Institute for Sea Research (NIOZ), Texel, The Netherlands;
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7
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Pan K, Zheng X, Liu X, Jiang H. Nitrogen cycling in a tropical coral reef ecosystem under severe anthropogenic disturbance in summer: Insights from isotopic compositions. WATER RESEARCH 2021; 207:117824. [PMID: 34758438 DOI: 10.1016/j.watres.2021.117824] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 10/18/2021] [Accepted: 10/30/2021] [Indexed: 06/13/2023]
Abstract
Coral reefs, one of the most productive ecosystems, have been dramatically declining in recent decades. While studies contend a prominent correlation between coral reef degradation and increased anthropogenic nitrogen (N) loads, a quantitative description of the N sources and cycling processes in these ecologically important ecosystems is lacking. Through a comprehensive depiction of the δ15N compositions of seawaters and sediments, we systematically accessed the N cycling processes in the Weizhou coral reef ecosystem. The correlations between the nitrate (NO3-) concentrations and isotopic compositions (δ15N/δ18O-NO3-) indicated the pelagic NO3- loads were largely regulated by mixing between precipitation and sewage. Biological NO3- turnover processes appeared to be weak. In the sediments, N2 fixation contributed about one-third of the sedimentary organic N, with the rest coming from the settlement of pelagic organic N. We also uncovered significant sedimentary mineralization-nitrification-denitrification processes in which the N loss was greater than the input. While pelagic N significantly contributed to the sedimentary N, the N export from the sediments to surface seawater was potentially short-circuited by the high N retention and recycling efficiencies of the organisms in the coral reef ecosystem. Overall, this study shows that the complex N cycling processes in the ecosystem are effectively reflected in the isotopic compositions of seawater and sediment, thus adding an important dimension to understanding the N cycling in coral reef ecosystems.
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Affiliation(s)
- Ke Pan
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China
| | - Xinqing Zheng
- Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, 361005, China
| | - Xinming Liu
- Institute of Marine Drugs, Guangxi University of Chinese Medicine, Nanning, 530200, China
| | - Hao Jiang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China.
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8
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Sturaro N, Hsieh YE, Chen Q, Wang P, Denis V. Trophic plasticity of mixotrophic corals under contrasting environments. Funct Ecol 2021. [DOI: 10.1111/1365-2435.13924] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Nicolas Sturaro
- Institute of Oceanography National Taiwan University Taipei Taiwan
| | - Yunli Eric Hsieh
- Institute of Oceanography National Taiwan University Taipei Taiwan
| | - Qi Chen
- Institute of Oceanography National Taiwan University Taipei Taiwan
| | - Pei‐Ling Wang
- Institute of Oceanography National Taiwan University Taipei Taiwan
- Research Center for Future Earth National Taiwan University Taipei Taiwan
| | - Vianney Denis
- Institute of Oceanography National Taiwan University Taipei Taiwan
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9
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Meunier V, Geissler L, Bonnet S, Rädecker N, Perna G, Grosso O, Lambert C, Rodolfo-Metalpa R, Voolstra CR, Houlbrèque F. Microbes support enhanced nitrogen requirements of coral holobionts in a high CO 2 environment. Mol Ecol 2021; 30:5888-5899. [PMID: 34473860 DOI: 10.1111/mec.16163] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 08/24/2021] [Accepted: 08/27/2021] [Indexed: 12/24/2022]
Abstract
Ocean acidification is posing a threat to calcifying organisms due to the increased energy requirements of calcification under high CO2 conditions. The ability of scleractinian corals to cope with future ocean conditions will thus depend on their ability to fulfil their carbon requirement. However, the primary productivity of coral holobionts is limited by low nitrogen (N) availability in coral reef waters. Here, we employed CO2 seeps of Tutum Bay (Papua New Guinea) as a natural laboratory to understand how coral holobionts offset their increased energy requirements under high CO2 conditions. Our results demonstrate for the first time that under high pCO2 conditions, N assimilation pathways of Pocillopora damicornis are jointly modified. We found that diazotroph-derived N assimilation rates in the Symbiodiniaceae were significantly higher in comparison to an ambient CO2 control site, concomitant with a restructured diazotroph community and the specific prevalence of an alpha-proteobacterium. Further, corals at the high CO2 site also had increased feeding rates on picoplankton and in particular exhibited selective feeding on Synechococcus sp., known to be rich in N. Given the high abundance of picoplankton in oligotrophic waters at large, our results suggest that corals exhibiting flexible diazotrophic communities and capable of exploiting N-rich picoplankton sources to offset their increased N requirements may be able to cope better in a high pCO2 world.
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Affiliation(s)
- Valentine Meunier
- Centre IRD Nouméa, UMR ENTROPIE (IRD, Université de La Réunion, CNRS, Université de La Nouvelle-Calédonie, Ifremer), Nouméa, New Caledonia
| | - Laura Geissler
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Sophie Bonnet
- Aix-Marseille Université, Université de Toulon, CNRS, IRD, Marseille, France
| | - Nils Rädecker
- Department of Biology, University of Konstanz, Konstanz, Germany.,Laboratory for Biological Geochemistry, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Gabriela Perna
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Olivier Grosso
- Aix-Marseille Université, Université de Toulon, CNRS, IRD, Marseille, France
| | | | - Riccardo Rodolfo-Metalpa
- Centre IRD Nouméa, UMR ENTROPIE (IRD, Université de La Réunion, CNRS, Université de La Nouvelle-Calédonie, Ifremer), Nouméa, New Caledonia
| | | | - Fanny Houlbrèque
- Centre IRD Nouméa, UMR ENTROPIE (IRD, Université de La Réunion, CNRS, Université de La Nouvelle-Calédonie, Ifremer), Nouméa, New Caledonia
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10
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Zhang Y, Yang Q, Zhang Y, Ahmad M, Ling J, Dong J, Wang Y. The diversity and metabolic potential of the microbial functional gene associated with Porites pukoensis. ECOTOXICOLOGY (LONDON, ENGLAND) 2021; 30:986-995. [PMID: 33991262 DOI: 10.1007/s10646-021-02419-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 04/28/2021] [Indexed: 06/12/2023]
Abstract
Coral reef ecosystems usually distribute in oligotrophic tropical and subtropical marine environments, but they possess great biodiversity and high productivity. It may attribute to its efficient internal nutrient cycle system. However, the knowledge of functional microbial community structure is still limited. In this study, both functional gene array (Geochip 5.0) and nifH Illumina sequencing were used to profile the overall functional genes and diazotrophic communities associated with coral Porites pukoensis. More than 7500 microbial functional genes were detected from archaea, bacteria, and fungi. Most of these genes are related to the transformation of carbon, nitrogen, sulfur, and phosphorus, providing evidence that microbes in the coral holobiont play important roles in the biogeochemical cycle of coral reef ecosystems. Our results indicated a high diversity of diazotrophs associated with corals. The dominant diazotrophic groups were related to phyla Alphaproteobacteria, Deltaproteobacteria, Cyanobacteria, and Gammaproteobacteria. And the dominant diazotrophic communities were divided into four clusters. They were affiliated with nifH sequences from genera Zymomonas, Halorhodospira, Leptolyngbya, Trichormus, and Desulfovibrio, indicating these groups may play a more important role in the nitrogen-fixing process in the coral holobiont. This study revealed functional gene diversity and suggested the roles they played in the biogeochemical cycling of the coral holobiont.
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Affiliation(s)
- Yanying Zhang
- Ocean School, Yantai University, Yantai, 264005, China.
| | - Qingsong Yang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China
| | - Ying Zhang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China
| | - Manzoor Ahmad
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China
| | - Juan Ling
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China
| | - Junde Dong
- Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China.
- Key Laboratory of Tropical Marine Biotechnology of Hainan Province and Hainan Sanya Marine Ecosystem National Observation and Research Station, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Sanya, 572000, China.
| | - Youshao Wang
- State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China
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11
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Bednarz VN, van de Water JAJM, Grover R, Maguer JF, Fine M, Ferrier-Pagès C. Unravelling the Importance of Diazotrophy in Corals - Combined Assessment of Nitrogen Assimilation, Diazotrophic Community and Natural Stable Isotope Signatures. Front Microbiol 2021; 12:631244. [PMID: 34248863 PMCID: PMC8264265 DOI: 10.3389/fmicb.2021.631244] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 05/28/2021] [Indexed: 11/22/2022] Open
Abstract
There is an increasing interest in understanding the structure and function of the microbiota associated with marine and terrestrial organisms, because it can play a major role in host nutrition and resistance to environmental stress. Reef-building corals live in association with diazotrophs, which are microbes able to fix dinitrogen. Corals are known to assimilate diazotrophically-derived nitrogen (DDN), but it is still not clear whether this nitrogen source is derived from coral-associated diazotrophs and whether it substantially contributes to the coral’s nitrogen budget. In this study, we aimed to provide a better understanding of the importance of DDN for corals using a holistic approach by simultaneously assessing DDN assimilation rates (using 15N2 tracer technique), the diazotrophic bacterial community (using nifH gene amplicon sequencing) and the natural δ15N signature in Stylophora pistillata corals from the Northern Red Sea along a depth gradient in winter and summer. Overall, our results show a discrepancy between the three parameters. DDN was assimilated by the coral holobiont during winter only, with an increased assimilation with depth. Assimilation rates were, however, not linked to the presence of coral-associated diazotrophs, suggesting that the presence of nifH genes does not necessarily imply functionality. It also suggests that DDN assimilation was independent from coral-associated diazotrophs and may instead result from nitrogen derived from planktonic diazotrophs. In addition, the δ15N signature presented negative values in almost all coral samples in both seasons, suggesting that nitrogen sources other than DDN contribute to the nitrogen budget of corals from this region. This study yields novel insight into the origin and importance of diazotrophy for scleractinian corals from the Northern Red Sea using multiple proxies.
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Affiliation(s)
- Vanessa N Bednarz
- Marine Department, Centre Scientifique de Monaco, Monaco City, Monaco
| | | | - Renaud Grover
- Marine Department, Centre Scientifique de Monaco, Monaco City, Monaco
| | - Jean-François Maguer
- Laboratoire des Sciences de l'Environnement Marin (LEMAR), UMR 6539 UBO/CNRS/IRD/IFREMER, Institut Universitaire Européen de la Mer, Plouzané, France
| | - Maoz Fine
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel.,The Interuniversity Institute for Marine Sciences, Eilat, Israel
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12
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Tilstra A, Roth F, El-Khaled YC, Pogoreutz C, Rädecker N, Voolstra CR, Wild C. Relative abundance of nitrogen cycling microbes in coral holobionts reflects environmental nitrate availability. ROYAL SOCIETY OPEN SCIENCE 2021; 8:201835. [PMID: 34109033 PMCID: PMC8170195 DOI: 10.1098/rsos.201835] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 05/14/2021] [Indexed: 06/12/2023]
Abstract
Recent research suggests that nitrogen (N) cycling microbes are important for coral holobiont functioning. In particular, coral holobionts may acquire bioavailable N via prokaryotic dinitrogen (N2) fixation or remove excess N via denitrification activity. However, our understanding of environmental drivers on these processes in hospite remains limited. Employing the strong seasonality of the central Red Sea, this study assessed the effects of environmental parameters on the proportional abundances of N cycling microbes associated with the hard corals Acropora hemprichii and Stylophora pistillata. Specifically, we quantified changes in the relative ratio between nirS and nifH gene copy numbers, as a proxy for seasonal shifts in denitrification and N2 fixation potential in corals, respectively. In addition, we assessed coral tissue-associated Symbiodiniaceae cell densities and monitored environmental parameters to provide a holobiont and environmental context, respectively. While ratios of nirS to nifH gene copy numbers varied between seasons, they revealed similar seasonal patterns in both coral species, with ratios closely following patterns in environmental nitrate availability. Symbiodiniaceae cell densities aligned with environmental nitrate availability, suggesting that the seasonal shifts in nirS to nifH gene abundance ratios were probably driven by nitrate availability in the coral holobiont. Thereby, our results suggest that N cycling in coral holobionts probably adjusts to environmental conditions by increasing and/or decreasing denitrification and N2 fixation potential according to environmental nitrate availability. Microbial N cycling may, thus, extenuate the effects of changes in environmental nitrate availability on coral holobionts to support the maintenance of the coral-Symbiodiniaceae symbiosis.
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Affiliation(s)
- Arjen Tilstra
- Marine Ecology Department, Faculty of Biology and Chemistry, University of Bremen, Bremen, Germany
| | - Florian Roth
- Red Sea Research Center, King Abdullah University of Science and Technology, Thuwal, Kingdom of Saudi Arabia
- Baltic Sea Centre, Stockholm University, Stockholm, Sweden
- Tvärminne Zoological Station, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Yusuf C. El-Khaled
- Marine Ecology Department, Faculty of Biology and Chemistry, University of Bremen, Bremen, Germany
| | - Claudia Pogoreutz
- Red Sea Research Center, King Abdullah University of Science and Technology, Thuwal, Kingdom of Saudi Arabia
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Nils Rädecker
- Red Sea Research Center, King Abdullah University of Science and Technology, Thuwal, Kingdom of 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 (EPFL), Lausanne, Switzerland
| | - Christian R. Voolstra
- Red Sea Research Center, King Abdullah University of Science and Technology, Thuwal, Kingdom of Saudi Arabia
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Christian Wild
- Marine Ecology Department, Faculty of Biology and Chemistry, University of Bremen, Bremen, Germany
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13
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Ford AK, Visser PM, van Herk MJ, Jongepier E, Bonito V. First insights into the impacts of benthic cyanobacterial mats on fish herbivory functions on a nearshore coral reef. Sci Rep 2021; 11:7147. [PMID: 33785764 PMCID: PMC8009962 DOI: 10.1038/s41598-021-84016-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 02/04/2021] [Indexed: 11/22/2022] Open
Abstract
Benthic cyanobacterial mats (BCMs) are becoming increasingly common on coral reefs. In Fiji, blooms generally occur in nearshore areas during warm months but some are starting to prevail through cold months. Many fundamental knowledge gaps about BCM proliferation remain, including their composition and how they influence reef processes. This study examined a seasonal BCM bloom occurring in a 17-year-old no-take inshore reef area in Fiji. Surveys quantified the coverage of various BCM-types and estimated the biomass of key herbivorous fish functional groups. Using remote video observations, we compared fish herbivory (bite rates) on substrate covered primarily by BCMs (> 50%) to substrate lacking BCMs (< 10%) and looked for indications of fish (opportunistically) consuming BCMs. Samples of different BCM-types were analysed by microscopy and next-generation amplicon sequencing (16S rRNA). In total, BCMs covered 51 ± 4% (mean ± s.e.m) of the benthos. Herbivorous fish biomass was relatively high (212 ± 36 kg/ha) with good representation across functional groups. Bite rates were significantly reduced on BCM-dominated substratum, and no fish were unambiguously observed consuming BCMs. Seven different BCM-types were identified, with most containing a complex consortium of cyanobacteria. These results provide insight into BCM composition and impacts on inshore Pacific reefs.
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Affiliation(s)
- Amanda K Ford
- School of Agriculture, Geography, Environment, Ocean and Natural Sciences (SAGEONS), University of the South Pacific, Suva, Fiji.
- Stockholm Resilience Centre, Stockholm University, Stockholm, Sweden.
| | - Petra M Visser
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Maria J van Herk
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Evelien Jongepier
- Bioinformatics, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
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Roth F, Karcher DB, Rädecker N, Hohn S, Carvalho S, Thomson T, Saalmann F, Voolstra CR, Kürten B, Struck U, Jones BH, Wild C. High rates of carbon and dinitrogen fixation suggest a critical role of benthic pioneer communities in the energy and nutrient dynamics of coral reefs. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13625] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Florian Roth
- Red Sea Research Center King Abdullah University of Science and Technology (KAUST) Thuwal Saudi Arabia
- Baltic Sea Centre Stockholm University Stockholm Sweden
- Faculty of Biological and Environmental Sciences Tvärminne Zoological Station University of Helsinki Helsinki Finland
| | - Denis B. Karcher
- Marine Ecology Faculty of Biology and Chemistry University of Bremen Bremen Germany
| | - Nils Rädecker
- Red Sea Research Center King Abdullah University of Science and Technology (KAUST) Thuwal Saudi Arabia
- Laboratory for Biological Geochemistry School of Architecture Civil and Environmental Engineering Ecole Polytechnique Fédérale de Lausanne (EPFL) Lausanne Switzerland
| | - Sönke Hohn
- Systems Ecology Group Department of Theoretical Ecology and Modelling Leibniz Centre for Tropical Marine Research Bremen Germany
| | - Susana Carvalho
- Red Sea Research Center King Abdullah University of Science and Technology (KAUST) Thuwal Saudi Arabia
| | - Timothy Thomson
- Red Sea Research Center King Abdullah University of Science and Technology (KAUST) Thuwal Saudi Arabia
| | - Franziska Saalmann
- Marine Ecology Faculty of Biology and Chemistry University of Bremen Bremen Germany
- Faculty of Science and Engineering University of Groningen Groningen The Netherlands
| | - Christian R. Voolstra
- Red Sea Research Center King Abdullah University of Science and Technology (KAUST) Thuwal Saudi Arabia
- Department of Biology University of Konstanz Konstanz Germany
| | - Benjamin Kürten
- Red Sea Research Center King Abdullah University of Science and Technology (KAUST) Thuwal Saudi Arabia
- Jülich Research Centre GmbHProject Management Jülich Rostock Germany
| | - Ulrich Struck
- Museum für Naturkunde Leibniz Institute for Evolution and Biodiversity Science Berlin Germany
- Department of Earth Sciences Freie Universität Berlin Berlin Germany
| | - Burton H. Jones
- Red Sea Research Center King Abdullah University of Science and Technology (KAUST) Thuwal Saudi Arabia
| | - Christian Wild
- Marine Ecology Faculty of Biology and Chemistry University of Bremen Bremen Germany
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15
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Biagi E, Caroselli E, Barone M, Pezzimenti M, Teixido N, Soverini M, Rampelli S, Turroni S, Gambi MC, Brigidi P, Goffredo S, Candela M. Patterns in microbiome composition differ with ocean acidification in anatomic compartments of the Mediterranean coral Astroides calycularis living at CO 2 vents. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 724:138048. [PMID: 32251879 DOI: 10.1016/j.scitotenv.2020.138048] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 03/02/2020] [Accepted: 03/17/2020] [Indexed: 06/11/2023]
Abstract
Coral microbiomes, the complex microbial communities associated with the different anatomic compartments of the coral, provide important functions for the host's survival, such as nutrient cycling at the host's surface, prevention of pathogens colonization, and promotion of nutrient uptake. Microbiomes are generally referred to as plastic entities, able to adapt their composition and functionality in response to environmental change, with a possible impact on coral acclimatization to phenomena related to climate change, such as ocean acidification. Ocean sites characterized by natural gradients of pCO2 provide models for investigating the ability of marine organisms to acclimatize to decreasing seawater pH. Here we compared the microbiome of the temperate, shallow water, non-symbiotic solitary coral Astroides calycularis that naturally lives at a volcanic CO2 vent in Ischia Island (Naples, Italy), with that of corals living in non-acidified sites at the same island. Bacterial DNA associated with the different anatomic compartments (mucus, tissue and skeleton) of A. calycularis was differentially extracted and a total of 68 samples were analyzed by 16S rRNA gene sequencing. In terms of phylogenetic composition, the microbiomes associated with the different coral anatomic compartments were different from each other and from the microbial communities of the surrounding seawater. Of all the anatomic compartments, the mucus-associated microbiome differed the most between the control and acidified sites. The differences detected in the microbial communities associated to the three anatomic compartments included a general increase in subdominant bacterial groups, some of which are known to be involved in different stages of the nitrogen cycle, such as potential nitrogen fixing bacteria and bacteria able to degrade organic nitrogen. Our data therefore suggests a potential increase of nitrogen fixation and recycling in A. calycularis living close to the CO2 vent system.
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Affiliation(s)
- Elena Biagi
- Unit of Holobiont Microbiome and Microbiome Engineering (HolobioME), Department of Pharmacy and Biotechnology, University of Bologna, via Belmeloro 6, 40126 Bologna, Italy
| | - Erik Caroselli
- Marine Science Group, Department of Biological, Geological and Environmental Sciences, University of Bologna, via Selmi 3, 40126 Bologna, Italy; Fano Marine Center, The Inter-Institute Center for Research on Marine Biodiversity, Resources and Biotechnologies, viale Adriatico 1/N, 61032 Fano, Pesaro Urbino, Italy
| | - Monica Barone
- Unit of Holobiont Microbiome and Microbiome Engineering (HolobioME), Department of Pharmacy and Biotechnology, University of Bologna, via Belmeloro 6, 40126 Bologna, Italy
| | - Martina Pezzimenti
- Marine Science Group, Department of Biological, Geological and Environmental Sciences, University of Bologna, via Selmi 3, 40126 Bologna, Italy
| | - Nuria Teixido
- Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefranche, 181 chemin du Lazaret, F-06230 Villefranche-sur-Mer, France; Villa Dohrn-Benthic Ecology Center, Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, 80077 Ischia (Naples), Italy
| | - Matteo Soverini
- Unit of Holobiont Microbiome and Microbiome Engineering (HolobioME), Department of Pharmacy and Biotechnology, University of Bologna, via Belmeloro 6, 40126 Bologna, Italy
| | - Simone Rampelli
- Unit of Holobiont Microbiome and Microbiome Engineering (HolobioME), Department of Pharmacy and Biotechnology, University of Bologna, via Belmeloro 6, 40126 Bologna, Italy
| | - Silvia Turroni
- Unit of Holobiont Microbiome and Microbiome Engineering (HolobioME), Department of Pharmacy and Biotechnology, University of Bologna, via Belmeloro 6, 40126 Bologna, Italy
| | - Maria Cristina Gambi
- Villa Dohrn-Benthic Ecology Center, Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, 80077 Ischia (Naples), Italy
| | - Patrizia Brigidi
- Unit of Holobiont Microbiome and Microbiome Engineering (HolobioME), Department of Pharmacy and Biotechnology, University of Bologna, via Belmeloro 6, 40126 Bologna, Italy
| | - Stefano Goffredo
- Marine Science Group, Department of Biological, Geological and Environmental Sciences, University of Bologna, via Selmi 3, 40126 Bologna, Italy; Fano Marine Center, The Inter-Institute Center for Research on Marine Biodiversity, Resources and Biotechnologies, viale Adriatico 1/N, 61032 Fano, Pesaro Urbino, Italy.
| | - Marco Candela
- Unit of Holobiont Microbiome and Microbiome Engineering (HolobioME), Department of Pharmacy and Biotechnology, University of Bologna, via Belmeloro 6, 40126 Bologna, Italy; Fano Marine Center, The Inter-Institute Center for Research on Marine Biodiversity, Resources and Biotechnologies, viale Adriatico 1/N, 61032 Fano, Pesaro Urbino, Italy.
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16
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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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17
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Prazeres M, Martínez-Colón M, Hallock P. Foraminifera as bioindicators of water quality: The FoRAM Index revisited. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 257:113612. [PMID: 31784269 DOI: 10.1016/j.envpol.2019.113612] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 11/10/2019] [Accepted: 11/10/2019] [Indexed: 06/10/2023]
Abstract
Coral reefs worldwide are degrading at alarming rates due to local and global stressors. There are ongoing needs for bioindicator systems that can be used to assess reef health status, the potential for recovery following destructive events such as tropical storms, and for the success of coral transplants. Benthic foraminiferal shells are ubiquitous components of carbonate sediment in reef environments that can be sampled at minimal cost and environmental impact. Here we review the development and application of the FoRAM Index (FI), which provides a bioindicator metric for water quality that supports reef accretion. We outline the strengths and limitations of the FI, and propose how it can be applied more effectively across different geographical regions.
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Affiliation(s)
- Martina Prazeres
- Marine Biodiversity Group, Naturalis Biodiversity Center, Leiden, Netherlands.
| | | | - Pamela Hallock
- College of Marine Science, University of South Florida, St. Petersburg, FL, USA
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18
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A genomic view of the reef-building coral Porites lutea and its microbial symbionts. Nat Microbiol 2019; 4:2090-2100. [DOI: 10.1038/s41564-019-0532-4] [Citation(s) in RCA: 104] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 07/05/2019] [Indexed: 11/09/2022]
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19
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Yang SH, Tandon K, Lu CY, Wada N, Shih CJ, Hsiao SSY, Jane WN, Lee TC, Yang CM, Liu CT, Denis V, Wu YT, Wang LT, Huang L, Lee DC, Wu YW, Yamashiro H, Tang SL. Metagenomic, phylogenetic, and functional characterization of predominant endolithic green sulfur bacteria in the coral Isopora palifera. MICROBIOME 2019; 7:3. [PMID: 30609942 PMCID: PMC6320609 DOI: 10.1186/s40168-018-0616-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 12/21/2018] [Indexed: 05/13/2023]
Abstract
BACKGROUND Endolithic microbes in coral skeletons are known to be a nutrient source for the coral host. In addition to aerobic endolithic algae and Cyanobacteria, which are usually described in the various corals and form a green layer beneath coral tissues, the anaerobic photoautotrophic green sulfur bacteria (GSB) Prosthecochloris is dominant in the skeleton of Isopora palifera. However, due to inherent challenges in studying anaerobic microbes in coral skeleton, the reason for its niche preference and function are largely unknown. RESULTS This study characterized a diverse and dynamic community of endolithic microbes shaped by the availability of light and oxygen. In addition, anaerobic bacteria isolated from the coral skeleton were cultured for the first time to experimentally clarify the role of these GSB. This characterization includes GSB's abundance, genetic and genomic profiles, organelle structure, and specific metabolic functions and activity. Our results explain the advantages endolithic GSB receive from living in coral skeletons, the potential metabolic role of a clade of coral-associated Prosthecochloris (CAP) in the skeleton, and the nitrogen fixation ability of CAP. CONCLUSION We suggest that the endolithic microbial community in coral skeletons is diverse and dynamic and that light and oxygen are two crucial factors for shaping it. This study is the first to demonstrate the ability of nitrogen uptake by specific coral-associated endolithic bacteria and shed light on the role of endolithic bacteria in coral skeletons.
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Affiliation(s)
- Shan-Hua Yang
- Biodiversity Research Center, Academia Sinica, Taipei, 11529 Taiwan
- Tropical Biosphere Research Center, University of the Ryukyus, Okinawa, 905-0227 Japan
- Department of Life Science, Tunghai University, Taichung, 40704 Taiwan
- Center for Ecology and Environment, Tunghai University, Taichung, 40704 Taiwan
| | - Kshitij Tandon
- Biodiversity Research Center, Academia Sinica, Taipei, 11529 Taiwan
- Bioinformatics Program, Institute of Information Science, Taiwan International Graduate Program, Academia Sinica, Taipei, 11529 Taiwan
- Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsinchu, 30013 Taiwan
| | - Chih-Ying Lu
- Biodiversity Research Center, Academia Sinica, Taipei, 11529 Taiwan
| | - Naohisa Wada
- Biodiversity Research Center, Academia Sinica, Taipei, 11529 Taiwan
| | - Chao-Jen Shih
- Bioresource Collection and Research Center, Food Industry Research and Development Institute, Hsinchu, 30062 Taiwan
| | - Silver Sung-Yun Hsiao
- Institute of Earth Sciences, Academia Sinica, Taipei, 11529 Taiwan
- Institute of Astronomy and Astrophysics, Academia Sinica, Taipei, 11529 Taiwan
| | - Wann-Neng Jane
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, 11529 Taiwan
| | - Tzan-Chain Lee
- Biodiversity Research Center, Academia Sinica, Taipei, 11529 Taiwan
| | - Chi-Ming Yang
- Biodiversity Research Center, Academia Sinica, Taipei, 11529 Taiwan
| | - Chi-Te Liu
- Institute of Biotechnology, National Taiwan University, Taipei, 10672 Taiwan
| | - Vianney Denis
- Institute of Oceanography, National Taiwan University, Taipei, 10617 Taiwan
| | - Yu-Ting Wu
- Department of Forestry, National Pingtung University of Science and Technology, Pintung, 91201 Taiwan
| | - Li-Ting Wang
- Bioresource Collection and Research Center, Food Industry Research and Development Institute, Hsinchu, 30062 Taiwan
| | - Lina Huang
- Bioresource Collection and Research Center, Food Industry Research and Development Institute, Hsinchu, 30062 Taiwan
| | - Der-Chuen Lee
- Institute of Earth Sciences, Academia Sinica, Taipei, 11529 Taiwan
| | - Yu-Wei Wu
- Graduate Institute of Biomedical Informatics, College of Medical Science and Technology, Taipei Medical University, Taipei, 11031 Taiwan
| | - Hideyuki Yamashiro
- Tropical Biosphere Research Center, University of the Ryukyus, Okinawa, 905-0227 Japan
| | - Sen-Lin Tang
- Biodiversity Research Center, Academia Sinica, Taipei, 11529 Taiwan
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20
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Bednarz VN, van de Water JAJM, Rabouille S, Maguer JF, Grover R, Ferrier-Pagès C. Diazotrophic community and associated dinitrogen fixation within the temperate coral Oculina patagonica. Environ Microbiol 2018; 21:480-495. [PMID: 30452101 DOI: 10.1111/1462-2920.14480] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 10/25/2018] [Indexed: 01/08/2023]
Abstract
Dinitrogen (N2 ) fixing bacteria (diazotrophs) are an important source of new nitrogen in oligotrophic environments and represent stable members of the microbiome in tropical corals, while information on corals from temperate oligotrophic regions is lacking. Therefore, this study provides new insights into the diversity and activity of diazotrophs associated with the temperate coral Oculina patagonica from the Mediterranean Sea by combining metabarcoding sequencing of amplicons of both the 16S rRNA and nifH genes and 15 N2 stable isotope tracer analysis to assess diazotroph-derived nitrogen (DDN) assimilation by the coral. Results show that the diazotrophic community of O. patagonica is dominated by autotrophic bacteria (i.e. Cyanobacteria and Chlorobia). The majority of DDN was assimilated into the tissue and skeletal matrix, and DDN assimilation significantly increased in bleached corals. Thus, diazotrophs may constitute an additional nitrogen source for the coral host, when nutrient exchange with Symbiodinium is disrupted (e.g. bleaching) and external food supply is limited (e.g. oligotrophic summer season). Furthermore, we hypothesize that DDN can facilitate the fast proliferation of endolithic algae, which provide an alternative carbon source for bleached O. patagonica. Overall, O. patagonica could serve as a good model for investigating the importance of diazotrophs in coral recovery from bleaching.
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Affiliation(s)
- Vanessa N Bednarz
- Marine Department, Centre Scientifique de Monaco, 8 Quai Antoine Ier, MC-98000, Monaco, Principality of Monaco
| | - Jeroen A J M van de Water
- Marine Department, Centre Scientifique de Monaco, 8 Quai Antoine Ier, MC-98000, Monaco, Principality of Monaco
| | - Sophie Rabouille
- Sorbonne Universités, UPMC Univ Paris 06, UMR 7093, LOV, Observatoire océanologique, F-06230, Villefranche/mer, France.,CNRS, UMR 7093, LOV, Observatoire océanologique, F-06230, Villefranche/mer, France
| | - Jean-François Maguer
- LEMAR - UMR 6539 UBO/CNRS/IRD, Institut Universitaire Européen de la Mer, Place Nicolas Copernic, Plouzané 29280, France
| | - Renaud Grover
- Marine Department, Centre Scientifique de Monaco, 8 Quai Antoine Ier, MC-98000, Monaco, Principality of Monaco
| | - Christine Ferrier-Pagès
- Marine Department, Centre Scientifique de Monaco, 8 Quai Antoine Ier, MC-98000, Monaco, Principality of Monaco
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21
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Courtial L, Planas Bielsa V, Houlbrèque F, Ferrier-Pagès C. Effects of ultraviolet radiation and nutrient level on the physiological response and organic matter release of the scleractinian coral Pocillopora damicornis following thermal stress. PLoS One 2018; 13:e0205261. [PMID: 30356284 PMCID: PMC6200223 DOI: 10.1371/journal.pone.0205261] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 09/21/2018] [Indexed: 01/01/2023] Open
Abstract
Understanding which factors enhance or mitigate the impact of high temperatures on corals is crucial to predict the severity of coral bleaching worldwide. On the one hand, global warming is usually associated with high ultraviolet radiation levels (UVR), and surface water nutrient depletion due to stratification. On the other hand, eutrophication of coastal reefs increases levels of inorganic nutrients and decreases UVR, so that the effect of different combinations of these stressors on corals is unknown. In this study, we assessed the individual and crossed effects of high temperature, UVR and nutrient level on the key performance variables of the reef building coral Pocillopora damicornis. We found that seawater warming was the major stressor, which induced bleaching and impaired coral photosynthesis and calcification in all nutrient and UVR conditions. The strength of this effect however, was nutrient dependent. Corals maintained in nutrient-depleted conditions experienced the highest decrease in net photosynthesis under thermal stress, while nutrient enrichment (3 μM NO3- and 1 μM PO4+) slightly limited the negative impact of temperature through enhanced protein content, photosynthesis and respiration rates. UVR exposure had only an effect on total nitrogen release rates, which significantly decreased under normal growth conditions and tended to decrease also under thermal stress. This result suggests that increased level of UVR will lead to significant changes in the nutrient biogeochemistry of surface reef waters. Overall, our results show that environmental factors have different and interactive effects on each of the coral's physiological parameters, requiring multifactorial approaches to predict the future of coral reefs.
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Affiliation(s)
- Lucile Courtial
- Sorbonne Universités, UPMC Université Paris 6, IFD-ED 129, France
- Centre Scientifique de Monaco, 8 Quai Antoine 1er, Monaco, Principality of Monaco
- UMR ENTROPIE (IRD, Université de La Réunion, CNRS), Laboratoire d’Excellence « CORAIL», BP A5, Nouméa cedex, New Caledonia, France
| | - Victor Planas Bielsa
- Centre Scientifique de Monaco, 8 Quai Antoine 1er, Monaco, Principality of Monaco
| | - Fanny Houlbrèque
- UMR ENTROPIE (IRD, Université de La Réunion, CNRS), Laboratoire d’Excellence « CORAIL», BP A5, Nouméa cedex, New Caledonia, France
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22
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Van Duyl FC, Mueller B, Meesters EH. Spatio-temporal variation in stable isotope signatures (δ 13C and δ 15N) of sponges on the Saba Bank. PeerJ 2018; 6:e5460. [PMID: 30128208 PMCID: PMC6097495 DOI: 10.7717/peerj.5460] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 07/26/2018] [Indexed: 12/02/2022] Open
Abstract
Sponges are ubiquitous on coral reefs, mostly long lived and therefore adaptive to changing environmental conditions. They feed on organic matter withdrawn from the passing water and they may harbor microorganisms (endosymbionts), which contribute to their nutrition. Their diets and stable isotope (SI) fractionation determine the SI signature of the sponge holobiont. Little is known of spatio–temporal variations in SI signatures of δ13C and δ15N in tropical sponges and whether they reflect variations in the environment. We investigated the SI signatures of seven common sponge species with different functional traits and their potential food sources between 15 and 32 m depth along the S-SE and E-NE side of the Saba Bank, Eastern Caribbean, in October 2011 and October 2013. SI signatures differed significantly between most sponge species, both in mean values and in variation, indicating different food preferences and/or fractionation, inferring sponge species-specific isotopic niche spaces. In 2011, all sponge species at the S-SE side were enriched in d13C compared to the E-NE side. In 2013, SI signatures of sponges did not differ between the two sides and were overall lighter in δ13C and δ15N than in 2011. Observed spatio–temporal changes in SI in sponges could not be attributed to changes in the SI signatures of their potential food sources, which remained stable with different SI signatures of pelagic (particulate organic matter (POM): δ13C −24.9‰, δ15N +4.3‰) and benthic-derived food (macroalgae: δ13C −15.4‰, δ15N +0.8‰). Enriched δ13C signatures in sponges at the S-SE side in 2011 are proposed to be attributed to predominantly feeding on benthic-derived C. This interpretation was supported by significant differences in water mass constituents between sides in October 2011. Elevated NO3 and dissolved organic matter concentrations point toward a stronger reef signal in reef overlying water at the S-SE than N-NE side of the Bank in 2011. The depletions of δ13C and δ15N in sponges in October 2013 compared to October 2011 concurred with significantly elevated POM concentrations. The contemporaneous decrease in δ15N suggests that sponges obtain their N mostly from benthic-derived food with a lower δ15N than pelagic food. Average proportional feeding on available sources varied between sponge species and ranged from 20% to 50% for benthic and 50% to 80% for pelagic-derived food, assuming trophic enrichment factors of 0.5‰ ± sd 0.5 for δ13C and 3‰ ± sd 0.5 for δ15N for sponges. We suggest that observed variation of SI in sponges between sides and years were the result of shifts in the proportion of ingested benthic- and pelagic-derived organic matter driven by environmental changes. We show that sponge SI signatures reflect environmental variability in space and time on the Saba Bank and that SI of sponges irrespective of their species-specific traits move in a similar direction in response to these environmental changes.
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Affiliation(s)
- Fleur C Van Duyl
- Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research and Utrecht University, Den Burg, The Netherlands
| | - Benjamin Mueller
- Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research and Utrecht University, Den Burg, The Netherlands.,Department for Freshwater and Marine Ecology, University of Amsterdam, Amsterdam, The Netherlands
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23
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Bednarz VN, Naumann MS, Cardini U, van Hoytema N, Rix L, Al-Rshaidat MMD, Wild C. Contrasting seasonal responses in dinitrogen fixation between shallow and deep-water colonies of the model coral Stylophora pistillata in the northern Red Sea. PLoS One 2018; 13:e0199022. [PMID: 29902263 PMCID: PMC6002246 DOI: 10.1371/journal.pone.0199022] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 05/30/2018] [Indexed: 01/08/2023] Open
Abstract
Tropical corals are often associated with dinitrogen (N2)-fixing bacteria (diazotrophs), and seasonal changes in key environmental parameters, such as dissolved inorganic nitrogen (DIN) availability and seawater temperature, are known to affect N2 fixation in coral-microbial holobionts. Despite, then, such potential for seasonal and depth-related changes in N2 fixation in reef corals, such variation has not yet been investigated. Therefore, this study quantified seasonal (winter vs. summer) N2 fixation rates associated with the reef-building coral Stylophora pistillata collected from depths of 5, 10 and 20 m in the northern Gulf of Aqaba (Red Sea). Findings revealed that corals from all depths exhibited the highest N2 fixation rates during the oligotrophic summer season, when up to 11% of their photo-metabolic nitrogen demand (CPND) could be met by N2 fixation. While N2 fixation remained seasonally stable for deep corals (20 m), it significantly decreased for the shallow corals (5 and 10 m) during the DIN-enriched winter season, accounting for less than 2% of the corals’ CPND. This contrasting seasonal response in N2 fixation across corals of different depths could be driven by 1) release rates of coral-derived organic matter, 2) the community composition of the associated diazotrophs, and/or 3) nutrient acquisition by the Symbiodinium community.
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Affiliation(s)
- Vanessa N. Bednarz
- Coral Reef Ecology Group, Leibniz Centre for Tropical Marine Research (ZMT), Bremen, Germany
- Marine Department, Centre Scientifique de Monaco, Principality of Monaco
- * E-mail:
| | - Malik S. Naumann
- Coral Reef Ecology Group, Leibniz Centre for Tropical Marine Research (ZMT), Bremen, Germany
| | - Ulisse Cardini
- Coral Reef Ecology Group, Leibniz Centre for Tropical Marine Research (ZMT), Bremen, Germany
- Integrative Marine Ecology Department, Stazione Zoologica Anton Dohrn, Villa Comunale, Naples, Italy
| | - Nanne van Hoytema
- Coral Reef Ecology Group, Leibniz Centre for Tropical Marine Research (ZMT), Bremen, Germany
| | - Laura Rix
- Coral Reef Ecology Group, Leibniz Centre for Tropical Marine Research (ZMT), Bremen, Germany
- RD3 Marine Microbiology, GEOMAR Helmholtz Centre for Ocean Research, Kiel, Germany
| | - Mamoon M. D. Al-Rshaidat
- Laboratory for Molecular Microbial Ecology, Marine Science Station, Aqaba, Jordan
- Molecular and Microbial Ecology, Department of Biological Sciences, The University of Jordan, Amman, Jordan
| | - Christian Wild
- Coral Reef Ecology Group, Leibniz Centre for Tropical Marine Research (ZMT), Bremen, Germany
- Marine Ecology Group, Faculty of Biology and Chemistry, University of Bremen, Bremen, Germany
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24
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Nishihara A, Haruta S, McGlynn SE, Thiel V, Matsuura K. Nitrogen Fixation in Thermophilic Chemosynthetic Microbial Communities Depending on Hydrogen, Sulfate, and Carbon Dioxide. Microbes Environ 2018; 33:10-18. [PMID: 29367473 PMCID: PMC5877335 DOI: 10.1264/jsme2.me17134] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 10/28/2017] [Indexed: 12/20/2022] Open
Abstract
The activity of nitrogen fixation measured by acetylene reduction was examined in chemosynthetic microbial mats at 72-75°C in slightly-alkaline sulfidic hot springs in Nakabusa, Japan. Nitrogenase activity markedly varied from sampling to sampling. Nitrogenase activity did not correlate with methane production, but was detected in samples showing methane production levels less than the maximum amount, indicating a possible redox dependency of nitrogenase activity. Nitrogenase activity was not affected by 2-bromo-ethane sulfonate, an inhibitor of methanogenesis. However, it was inhibited by the addition of molybdate, an inhibitor of sulfate reduction and sulfur disproportionation, suggesting the involvement of sulfate-reducing or sulfur-disproportionating organisms. Nitrogenase activity was affected by different O2 concentrations in the gas phase, again supporting the hypothesis of a redox potential dependency, and was decreased by the dispersion of mats with a homogenizer. The loss of activity that occurred from dispersion was partially recovered by the addition of H2, sulfate, and carbon dioxide. These results suggested that the observed activity of nitrogen fixation was related to chemoautotrophic sulfate reducers, and fixation may be active in a limited range of ambient redox potential. Since thermophilic chemosynthetic communities may resemble ancient microbial communities before the appearance of photosynthesis, the present results may be useful when considering the ancient nitrogen cycle on earth.
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Affiliation(s)
- Arisa Nishihara
- Department of Biological Sciences, Tokyo Metropolitan UniversityMinami-Osawa, Hachioji, Tokyo 192–0397Japan
| | - Shin Haruta
- Department of Biological Sciences, Tokyo Metropolitan UniversityMinami-Osawa, Hachioji, Tokyo 192–0397Japan
| | - Shawn E. McGlynn
- Department of Biological Sciences, Tokyo Metropolitan UniversityMinami-Osawa, Hachioji, Tokyo 192–0397Japan
- Earth-Life Science Institute, Tokyo Institute of TechnologyOokayama, Meguro-ku, Tokyo 152–8551Japan
- Biofunctional Catalyst Research Team, RIKEN Center for Sustainable Resource ScienceWako-shi 351–0198Japan
- Blue Marble Space Institute of ScienceSeattle, WA 98145–1561USA
| | - Vera Thiel
- Department of Biological Sciences, Tokyo Metropolitan UniversityMinami-Osawa, Hachioji, Tokyo 192–0397Japan
| | - Katsumi Matsuura
- Department of Biological Sciences, Tokyo Metropolitan UniversityMinami-Osawa, Hachioji, Tokyo 192–0397Japan
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Abstract
Tropical scleractinian corals are dependent to varying degrees on their photosymbiotic partners. Under normal levels of temperature and irradiance, they can provide most, but not all, of the host's nutritional requirements. Heterotrophy is required to adequately supply critical nutrients, especially nitrogen and phosphorus. Scleractinian corals are known as mesozooplankton predators, and most employ tentacle capture. The ability to trap nano- and picoplankton has been demonstrated by several coral species and appears to fulfill a substantial proportion of their daily metabolic requirements. The mechanism of capture likely involves mucociliary activity or extracoelenteric digestion, but the relative contribution of these avenues have not been evaluated. Many corals employ mesenterial filaments to procure food in various forms, but the functional morphology and chemical activities of these structures have been poorly documented. Corals are capable of acquiring nutrition from particulate and dissolved organic matter, although the degree of reliance on these sources generally has not been established. Corals, including tropical, deep- and cold-water species, are known as a major source of carbon and other nutrients for benthic communities through the secretion of mucus, despite wide variation in chemical composition. Mucus is cycled through the planktonic microbial loop, the benthos, and the microbial community within the sediments. The consensus indicates that the dissolved organic fraction of mucus usually exceeds the insoluble portion, and both serve as sources for the growth of nano- and picoplankton. As many corals employ mucus to trap food, a portion is taken back during feeding. The net gain or loss has not been evaluated, although production is generally thought to exceed consumption. The same is true for the net uptake and loss of dissolved organic matter by mucus secretion. Octocorals are thought not to employ mucus capture or mesenterial filaments during feeding and generally rely on tentacular filtration of weakly swimming mesozooplankton, particulates, dissolved organic matter, and picoplankton. Nonsymbiotic species in the tropics favor phytoplankton and weakly swimming zooplankton. Azooxanthellate soft corals are opportunistic feeders and shift their diet according to the season from phyto- and nanoplankton in summer to primarily particulate organic matter (POM) in winter. Cold-water species favor POM, phytodetritus, microplankton, and larger zooplankton when available. Antipatharians apparently feed on mesozooplankton but also use mucus nets, possibly for capture of POM. Feeding modes in this group are poorly known.
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Affiliation(s)
- Walter M Goldberg
- Department of Biological Sciences, Florida International University, Miami, FL, USA.
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26
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Diazotroph diversity and nitrogen fixation in the coral Stylophora pistillata from the Great Barrier Reef. ISME JOURNAL 2017; 12:813-824. [PMID: 29222444 DOI: 10.1038/s41396-017-0008-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 10/15/2017] [Accepted: 10/20/2017] [Indexed: 12/30/2022]
Abstract
Diazotrophs, both Bacteria and Archaea, capable of fixing nitrogen (N2), are present in the tissues and mucous, of corals and can supplement the coral holobiont nitrogen budget with fixed nitrogen (N) in the form of ammonia (NH3). Stylophora pistillata from Heron Island on the Great Barrier Reef collected at 5 and 15 m, and experimentally manipulated in the laboratory, showed that the rates of net photosynthesis, steady state quantum yields of photosystem II (PSII) fluorescence (∆Fv/Fm') and calcification varied based on irradiance as expected. Rates of N2 fixation were, however, invariant across treatments while the amount of fixed N contributing to Symbiodinium spp. N demand is irradiance dependent. Additionally, both the Symbiodinium and diazotrophic communities are significantly different based on depth, and novel Cluster V nifH gene phylotypes, which are not known to fix nitrogen, were recovered. A functional analysis using PICRUSt also showed that shallow corals were enriched in genes involved in nitrogen metabolism, and N2 fixation specifically. Corals have evolved a number of strategies to derive nitrogen from organic (e.g., heterotrophic feeding) and inorganic sources (e.g., N2 fixation) to maintain critical pathways such as protein synthesis to succeed ecologically in nitrogen-limited habitats.
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27
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The Assimilation of Diazotroph-Derived Nitrogen by Scleractinian Corals Depends on Their Metabolic Status. mBio 2017; 8:mBio.02058-16. [PMID: 28074021 PMCID: PMC5241398 DOI: 10.1128/mbio.02058-16] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Tropical corals are associated with a diverse community of dinitrogen (N2)-fixing prokaryotes (diazotrophs) providing the coral an additional source of bioavailable nitrogen (N) in oligotrophic waters. The overall activity of these diazotrophs changes depending on the current environmental conditions, but to what extent it affects the assimilation of diazotroph-derived N (DDN) by corals is still unknown. Here, in a series of 15N2 tracer experiments, we directly quantified DDN assimilation by scleractinian corals from the Red Sea exposed to different environmental conditions. We show that DDN assimilation strongly varied with the corals’ metabolic status or with phosphate availability in the water. The very autotrophic shallow-water (~5 m) corals showed low or no DDN assimilation, which significantly increased under elevated phosphate availability (3 µM). Corals that depended more on heterotrophy (i.e., bleached and deep-water [~45 m] corals) assimilated significantly more DDN, which contributed up to 15% of the corals’ N demand (compared to 1% in shallow corals). Furthermore, we demonstrate that a substantial part of the DDN assimilated by deep corals was likely obtained from heterotrophic feeding on fixed N compounds and/or diazotrophic cells in the mucus. Conversely, in shallow corals, the net release of mucus, rich in organic carbon compounds, likely enhanced diazotroph abundance and activity and thereby the release of fixed N to the pelagic and benthic reef community. Overall, our results suggest that DDN assimilation by corals varies according to the environmental conditions and is likely linked to the capacity of the coral to acquire nutrients from seawater. Tropical corals are associated with specialized bacteria (i.e., diazotrophs) able to transform dinitrogen (N2) gas into a bioavailable form of nitrogen, but how much of this diazotroph-derived nitrogen (DDN) is assimilated by corals under different environmental conditions is still unknown. Here, we used 15N2 labeling to trace the fate of DDN within the coral symbiosis. We show that DDN is assimilated by both the animal host and the endosymbiotic algae. In addition, the amount of assimilated DDN was significantly greater in mesophotic, bleached, or phosphorus-enriched corals than in surface corals, which almost did not take up this nitrogen form. DDN can thus be of particular importance for the nutrient budget of corals whenever they are limited by the availability of other forms of dissolved nutrients.
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28
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Harborne AR, Rogers A, Bozec YM, Mumby PJ. Multiple Stressors and the Functioning of Coral Reefs. ANNUAL REVIEW OF MARINE SCIENCE 2017; 9:445-468. [PMID: 27575738 DOI: 10.1146/annurev-marine-010816-060551] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Coral reefs provide critical services to coastal communities, and these services rely on ecosystem functions threatened by stressors. By summarizing the threats to the functioning of reefs from fishing, climate change, and decreasing water quality, we highlight that these stressors have multiple, conflicting effects on functionally similar groups of species and their interactions, and that the overall effects are often uncertain because of a lack of data or variability among taxa. The direct effects of stressors on links among functional groups, such as predator-prey interactions, are particularly uncertain. Using qualitative modeling, we demonstrate that this uncertainty of stressor impacts on functional groups (whether they are positive, negative, or neutral) can have significant effects on models of ecosystem stability, and reducing uncertainty is vital for understanding changes to reef functioning. This review also provides guidance for future models of reef functioning, which should include interactions among functional groups and the cumulative effect of stressors.
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Affiliation(s)
- Alastair R Harborne
- Department of Biological Sciences, Florida International University, North Miami, Florida 33181;
- Marine Spatial Ecology Lab and Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia; , ,
| | - Alice Rogers
- Marine Spatial Ecology Lab and Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia; , ,
| | - Yves-Marie Bozec
- Marine Spatial Ecology Lab and Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia; , ,
| | - Peter J Mumby
- Marine Spatial Ecology Lab and Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia; , ,
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29
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Zhang Y, Yang Q, Ling J, Van Nostrand JD, Shi Z, Zhou J, Dong J. The Shifts of Diazotrophic Communities in Spring and Summer Associated with Coral Galaxea astreata, Pavona decussata, and Porites lutea. Front Microbiol 2016; 7:1870. [PMID: 27920768 PMCID: PMC5118425 DOI: 10.3389/fmicb.2016.01870] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 11/07/2016] [Indexed: 11/13/2022] Open
Abstract
The coral holobiont often resides in oligotrophic waters; both coral cells and their symbiotic dinoflagellates possess ammonium assimilation enzymes and potentially benefit from the nitrogen fixation of coral-associated diazotrophs. However, the seasonal dynamics of coral-associated diazotrophs are not well characterized. Here, the seasonal variations of diazotrophic communities associated with three corals, Galaxea astreata, Pavona decussata, and Porites lutea, were studied using nifH gene amplicon pyrosequencing techniques. Our results revealed a great diversity of coral-associated diazotrophs. nifH sequences related to Alphaproteobacteria, Deltaproteobacteria, and Gammaproteobacteria were ubiquitous and dominant in all corals in two seasons. In contrast with the coral P. decussata, both G. astreata and P. lutea showed significant seasonal changes in the diazotrophic communities and nifH gene abundance. Variable diazotroph groups accounted for a range from 11 to 49% within individual coral samples. Most of the variable diazotrophic groups from P. decussata were species-specific, however, the majority of overlapping variable groups in G. astreata and P. lutea showed the same seasonal variation characteristics. Rhodopseudomonas palustris- and Gluconacetobacter diazotrophicus-affiliated sequences were relatively abundant in the summer, whereas a nifH sequence related to Halorhodospira halophila was relatively abundant in spring G. astreata and P. lutea. The seasonal variations of all diazotrophic communities were significantly correlated with the seasonal shifts of ammonium and nitrate, suggesting that diazotrophs play an important role in the nitrogen cycle of the coral holobiont.
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Affiliation(s)
- Yanying Zhang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of SciencesGuangzhou, China; Tropical Marine Biological Research Station in Hainan, South China Sea Institute of Oceanology, Chinese Academy of SciencesSanya, China; Department of Microbiology and Plant Biology, Institute for Environmental Genomics, University of Oklahoma, NormanOK, USA
| | - Qingsong Yang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences Guangzhou, China
| | - Juan Ling
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences Guangzhou, China
| | - Joy D Van Nostrand
- Department of Microbiology and Plant Biology, Institute for Environmental Genomics, University of Oklahoma, Norman OK, USA
| | - Zhou Shi
- Department of Microbiology and Plant Biology, Institute for Environmental Genomics, University of Oklahoma, Norman OK, USA
| | - Jizhong Zhou
- Department of Microbiology and Plant Biology, Institute for Environmental Genomics, University of Oklahoma, Norman OK, USA
| | - Junde Dong
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of SciencesGuangzhou, China; Tropical Marine Biological Research Station in Hainan, South China Sea Institute of Oceanology, Chinese Academy of SciencesSanya, China
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30
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Petersen JM, Kemper A, Gruber-Vodicka H, Cardini U, van der Geest M, Kleiner M, Bulgheresi S, Mußmann M, Herbold C, Seah BKB, Antony CP, Liu D, Belitz A, Weber M. Chemosynthetic symbionts of marine invertebrate animals are capable of nitrogen fixation. Nat Microbiol 2016; 2:16195. [PMID: 27775707 PMCID: PMC6872982 DOI: 10.1038/nmicrobiol.2016.195] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 09/07/2016] [Indexed: 12/04/2022]
Abstract
Chemosynthetic symbioses are partnerships between invertebrate animals
and chemosynthetic bacteria. The latter are the primary producers, providing most of
the organic carbon needed for the animal host's nutrition. We sequenced genomes of
the chemosynthetic symbionts from the lucinid bivalve Loripes lucinalis and the stilbonematid nematode Laxus oneistus. The symbionts of both host species
encoded nitrogen fixation genes. This is remarkable as no marine chemosynthetic
symbiont was previously known to be capable of nitrogen fixation. We detected
nitrogenase expression by the symbionts of lucinid clams at the transcriptomic and
proteomic level. Mean stable nitrogen isotope values of Loripes lucinalis were within the range expected for fixed atmospheric
nitrogen, further suggesting active nitrogen fixation by the symbionts. The ability
to fix nitrogen may be widespread among chemosynthetic symbioses in oligotrophic
habitats, where nitrogen availability often limits primary productivity. The chemosynthetic symbionts of the bivalve Loripes lucinalis and nematode Laxus
oneistus are found to encode nitrogen fixation genes, with evidence for
active nitrogen fixation.
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Affiliation(s)
- Jillian M Petersen
- Department of Microbiology and Ecosystem Science, Division of Microbial Ecology, Research Network Chemistry meets Microbiology, University of Vienna, Althanstrasse 14, Vienna 1090, Austria.,Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, Bremen 28359, Germany
| | - Anna Kemper
- Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, Bremen 28359, Germany
| | - Harald Gruber-Vodicka
- Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, Bremen 28359, Germany
| | - Ulisse Cardini
- Department of Microbiology and Ecosystem Science, Division of Microbial Ecology, Research Network Chemistry meets Microbiology, University of Vienna, Althanstrasse 14, Vienna 1090, Austria
| | - Matthijs van der Geest
- Centre for Marine Biodiversity, Exploitation and Conservation (MARBEC), UMR 9190, IRD-IFREMER-CNRS-UM, Université de Montpellier, Montpellier Cedex 5 34095, France.,Department of Coastal Systems and Utrecht University, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, Texel, The Netherlands
| | - Manuel Kleiner
- Department of Geoscience, University of Calgary, 2500 University Drive Northwest, Alberta T2N 1N4, Canada
| | - Silvia Bulgheresi
- Archaea Biology and Ecogenomics Division, Department of Ecogenomics and Systems Biology, University of Vienna, Althanstrasse 14, Vienna 1090, Austria
| | - Marc Mußmann
- Department of Microbiology and Ecosystem Science, Division of Microbial Ecology, Research Network Chemistry meets Microbiology, University of Vienna, Althanstrasse 14, Vienna 1090, Austria
| | - Craig Herbold
- Department of Microbiology and Ecosystem Science, Division of Microbial Ecology, Research Network Chemistry meets Microbiology, University of Vienna, Althanstrasse 14, Vienna 1090, Austria
| | - Brandon K B Seah
- Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, Bremen 28359, Germany
| | - Chakkiath Paul Antony
- Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, Bremen 28359, Germany
| | - Dan Liu
- Department of Geoscience, University of Calgary, 2500 University Drive Northwest, Alberta T2N 1N4, Canada
| | - Alexandra Belitz
- Department of Microbiology and Ecosystem Science, Division of Microbial Ecology, Research Network Chemistry meets Microbiology, University of Vienna, Althanstrasse 14, Vienna 1090, Austria
| | - Miriam Weber
- HYDRA Institute for Marine Sciences, Elba Field Station, Campo nell'Elba, Livorno 54037, Italy
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31
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Cardini U, Bednarz VN, Naumann MS, van Hoytema N, Rix L, Foster RA, Al-Rshaidat MMD, Wild C. Functional significance of dinitrogen fixation in sustaining coral productivity under oligotrophic conditions. Proc Biol Sci 2016; 282:20152257. [PMID: 26511052 DOI: 10.1098/rspb.2015.2257] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Functional traits define species by their ecological role in the ecosystem. Animals themselves are host-microbe ecosystems (holobionts), and the application of ecophysiological approaches can help to understand their functioning. In hard coral holobionts, communities of dinitrogen (N2)-fixing prokaryotes (diazotrophs) may contribute a functional trait by providing bioavailable nitrogen (N) that could sustain coral productivity under oligotrophic conditions. This study quantified N2 fixation by diazotrophs associated with four genera of hermatypic corals on a northern Red Sea fringing reef exposed to high seasonality. We found N2 fixation activity to be 5- to 10-fold higher in summer, when inorganic nutrient concentrations were lowest and water temperature and light availability highest. Concurrently, coral gross primary productivity remained stable despite lower Symbiodinium densities and tissue chlorophyll a contents. In contrast, chlorophyll a content per Symbiodinium cell increased from spring to summer, suggesting that algal cells overcame limitation of N, an essential element for chlorophyll synthesis. In fact, N2 fixation was positively correlated with coral productivity in summer, when its contribution was estimated to meet 11% of the Symbiodinium N requirements. These results provide evidence of an important functional role of diazotrophs in sustaining coral productivity when alternative external N sources are scarce.
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Affiliation(s)
- Ulisse Cardini
- Coral Reef Ecology Group (CORE), Leibniz Center for Tropical Marine Ecology (ZMT), Fahrenheitstrasse 6, 28359 Bremen, Germany
| | - Vanessa N Bednarz
- Coral Reef Ecology Group (CORE), Leibniz Center for Tropical Marine Ecology (ZMT), Fahrenheitstrasse 6, 28359 Bremen, Germany
| | - Malik S Naumann
- Coral Reef Ecology Group (CORE), Leibniz Center for Tropical Marine Ecology (ZMT), Fahrenheitstrasse 6, 28359 Bremen, Germany
| | - Nanne van Hoytema
- Coral Reef Ecology Group (CORE), Leibniz Center for Tropical Marine Ecology (ZMT), Fahrenheitstrasse 6, 28359 Bremen, Germany
| | - Laura Rix
- Coral Reef Ecology Group (CORE), Leibniz Center for Tropical Marine Ecology (ZMT), Fahrenheitstrasse 6, 28359 Bremen, Germany
| | - Rachel A Foster
- Department of Ecology, Environment and Plant Sciences, Stockholm University, 10691 Stockholm, Sweden
| | - Mamoon M D Al-Rshaidat
- Laboratory for Molecular Microbial Ecology (LaMME), Marine Science Station, Aqaba 77110, Jordan Department of Marine Biology, The University of Jordan-Aqaba Branch, Aqaba 77110, Jordan
| | - Christian Wild
- Coral Reef Ecology Group (CORE), Leibniz Center for Tropical Marine Ecology (ZMT), Fahrenheitstrasse 6, 28359 Bremen, Germany Faculty of Biology and Chemistry (FB 2), University of Bremen, 28359 Bremen, Germany
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Cardini U, van Hoytema N, Bednarz VN, Rix L, Foster RA, Al-Rshaidat MMD, Wild C. Microbial dinitrogen fixation in coral holobionts exposed to thermal stress and bleaching. Environ Microbiol 2016; 18:2620-33. [PMID: 27234003 DOI: 10.1111/1462-2920.13385] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 05/20/2016] [Indexed: 11/30/2022]
Abstract
Coral holobionts (i.e., coral-algal-prokaryote symbioses) exhibit dissimilar thermal sensitivities that may determine which coral species will adapt to global warming. Nonetheless, studies simultaneously investigating the effects of warming on all holobiont members are lacking. Here we show that exposure to increased temperature affects key physiological traits of all members (herein: animal host, zooxanthellae and diazotrophs) of both Stylophora pistillata and Acropora hemprichii during and after thermal stress. S. pistillata experienced severe loss of zooxanthellae (i.e., bleaching) with no net photosynthesis at the end of the experiment. Conversely, A. hemprichii was more resilient to thermal stress. Exposure to increased temperature (+ 6°C) resulted in a drastic increase in daylight dinitrogen (N2 ) fixation, particularly in A. hemprichii (threefold compared with controls). After the temperature was reduced again to in situ levels, diazotrophs exhibited a reversed diel pattern of activity, with increased N2 fixation rates recorded only in the dark, particularly in bleached S. pistillata (twofold compared to controls). Concurrently, both animal hosts, but particularly bleached S. pistillata, reduced both organic matter release and heterotrophic feeding on picoplankton. Our findings indicate that physiological plasticity by coral-associated diazotrophs may play an important role in determining the response of coral holobionts to ocean warming.
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Affiliation(s)
- Ulisse Cardini
- Coral Reef Ecology Group (CORE), Leibniz Center for Tropical Marine Ecology (ZMT), Fahrenheitstr. 6, DE, 28359, Bremen, Germany.,Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, Research Network Chemistry meets Microbiology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
| | - Nanne van Hoytema
- Coral Reef Ecology Group (CORE), Leibniz Center for Tropical Marine Ecology (ZMT), Fahrenheitstr. 6, DE, 28359, Bremen, Germany
| | - Vanessa N Bednarz
- Coral Reef Ecology Group (CORE), Leibniz Center for Tropical Marine Ecology (ZMT), Fahrenheitstr. 6, DE, 28359, Bremen, Germany
| | - Laura Rix
- Coral Reef Ecology Group (CORE), Leibniz Center for Tropical Marine Ecology (ZMT), Fahrenheitstr. 6, DE, 28359, Bremen, Germany
| | - Rachel A Foster
- Department of Ecology, Environment and Plant Sciences, Stockholm University, SE, 10691, Stockholm, Germany
| | - Mamoon M D Al-Rshaidat
- Laboratory for Molecular Microbial Ecology (LaMME), Marine Science Station, Aqaba, 77110, Jordan.,Department of Marine Biology, The University of Jordan - Aqaba Branch, Aqaba, 77110, Jordan
| | - Christian Wild
- Coral Reef Ecology Group (CORE), Leibniz Center for Tropical Marine Ecology (ZMT), Fahrenheitstr. 6, DE, 28359, Bremen, Germany.,Faculty of Biology and Chemistry (FB 2), University of Bremen, DE, 28359, Bremen, Germany
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Benavides M, Houlbrèque F, Camps M, Lorrain A, Grosso O, Bonnet S. Diazotrophs: a non-negligible source of nitrogen for the tropical coral Stylophora pistillata. ACTA ACUST UNITED AC 2016; 219:2608-12. [PMID: 27335448 DOI: 10.1242/jeb.139451] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 06/14/2016] [Indexed: 12/20/2022]
Abstract
Corals are mixotrophs: they are able to fix inorganic carbon through the activity of their symbiotic dinoflagellates and to gain nitrogen from predation on plankton and uptake of dissolved organic and inorganic nutrients. They also live in close association with diverse diazotrophic communities, inhabiting their skeleton, tissue and mucus layer, which are able to fix dinitrogen (N2). The quantity of fixed N2 transferred to the corals and its distribution within coral compartments as well as the quantity of nitrogen assimilated through the ingestion of planktonic diazotrophs are still unknown. Here, we quantified nitrogen assimilation via (i) N2 fixation by symbiont diazotrophs, (ii) ingestion of cultured unicellular diazotrophs and (iii) ingestion of natural planktonic diazotrophs. We estimate that the ingestion of diazotrophs provides 0.76±0.15 µg N cm(-2) h(-1), suggesting that diazotrophs represent a non-negligible source of nitrogen for scleractinian corals.
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Affiliation(s)
- Mar Benavides
- Mediterranean Institute of Oceanography (MIO) - IRD/CNRS/Aix-Marseille University, Noumea 98848, New Caledonia
| | - Fanny Houlbrèque
- Laboratoire d'Excellence CORAIL, ENTROPIE (UMR9220), IRD, Noumea 98848, New Caledonia
| | - Mercedes Camps
- Mediterranean Institute of Oceanography (MIO) - IRD/CNRS/Aix-Marseille University, Noumea 98848, New Caledonia
| | - Anne Lorrain
- Laboratoire des Sciences de l'Environnement Marin, LEMAR (UMR 6539 UBO), CNRS, IRD, Ifremer, IRD Nouméa, Noumea 98848, New Caledonia
| | - Olivier Grosso
- Mediterranean Institute of Oceanography (MIO) - IRD/CNRS/Aix-Marseille University, 13288 Marseille, France
| | - Sophie Bonnet
- Mediterranean Institute of Oceanography (MIO) - IRD/CNRS/Aix-Marseille University, Noumea 98848, New Caledonia
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Lawler SN, Kellogg CA, France SC, Clostio RW, Brooke SD, Ross SW. Coral-Associated Bacterial Diversity Is Conserved across Two Deep-Sea Anthothela Species. Front Microbiol 2016; 7:458. [PMID: 27092120 PMCID: PMC4820459 DOI: 10.3389/fmicb.2016.00458] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 03/21/2016] [Indexed: 12/19/2022] Open
Abstract
Cold-water corals, similar to tropical corals, contain diverse and complex microbial assemblages. These bacteria provide essential biological functions within coral holobionts, facilitating increased nutrient utilization and production of antimicrobial compounds. To date, few cold-water octocoral species have been analyzed to explore the diversity and abundance of their microbial associates. For this study, 23 samples of the family Anthothelidae were collected from Norfolk (n = 12) and Baltimore Canyons (n = 11) from the western Atlantic in August 2012 and May 2013. Genetic testing found that these samples comprised two Anthothela species (Anthothela grandiflora and Anthothela sp.) and Alcyonium grandiflorum. DNA was extracted and sequenced with primers targeting the V4–V5 variable region of the 16S rRNA gene using 454 pyrosequencing with GS FLX Titanium chemistry. Results demonstrated that the coral host was the primary driver of bacterial community composition. Al. grandiflorum, dominated by Alteromonadales and Pirellulales had much higher species richness, and a distinct bacterial community compared to Anthothela samples. Anthothela species (A. grandiflora and Anthothela sp.) had very similar bacterial communities, dominated by Oceanospirillales and Spirochaetes. Additional analysis of core-conserved bacteria at 90% sample coverage revealed genus level conservation across Anthothela samples. This core included unclassified Oceanospirillales, Kiloniellales, Campylobacterales, and genus Spirochaeta. Members of this core were previously recognized for their functional capabilities in nitrogen cycling and suggest the possibility of a nearly complete nitrogen cycle within Anthothela species. Overall, many of the bacterial associates identified in this study have the potential to contribute to the acquisition and cycling of nutrients within the coral holobiont.
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Affiliation(s)
- Stephanie N Lawler
- College of Marine Science, University of South Florida, St. Petersburg FL, USA
| | - Christina A Kellogg
- U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center, St. Petersburg FL, USA
| | - Scott C France
- Department of Biology, University of Louisiana at Lafayette Lafayette, LA, USA
| | - Rachel W Clostio
- Department of Biology, University of Louisiana at Lafayette Lafayette, LA, USA
| | - Sandra D Brooke
- Coastal and Marine Laboratory, Florida State University, St. Teresa FL, USA
| | - Steve W Ross
- Center for Marine Science, University of North Carolina Wilmington Wilmington, NC, USA
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36
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Middelburg JJ, Mueller CE, Veuger B, Larsson AI, Form A, van Oevelen D. Discovery of symbiotic nitrogen fixation and chemoautotrophy in cold-water corals. Sci Rep 2015; 5:17962. [PMID: 26644069 PMCID: PMC4672307 DOI: 10.1038/srep17962] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 11/09/2015] [Indexed: 11/17/2022] Open
Abstract
Cold-water corals (CWC) are widely distributed around the world forming extensive reefs at par with tropical coral reefs. They are hotspots of biodiversity and organic matter processing in the world’s deep oceans. Living in the dark they lack photosynthetic symbionts and are therefore considered to depend entirely on the limited flux of organic resources from the surface ocean. While symbiotic relations in tropical corals are known to be key to their survival in oligotrophic conditions, the full metabolic capacity of CWC has yet to be revealed. Here we report isotope tracer evidence for efficient nitrogen recycling, including nitrogen assimilation, regeneration, nitrification and denitrification. Moreover, we also discovered chemoautotrophy and nitrogen fixation in CWC and transfer of fixed nitrogen and inorganic carbon into bulk coral tissue and tissue compounds (fatty acids and amino acids). This unrecognized yet versatile metabolic machinery of CWC conserves precious limiting resources and provides access to new nitrogen and organic carbon resources that may be essential for CWC to survive in the resource-depleted dark ocean.
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Affiliation(s)
- Jack J Middelburg
- Department of Earth Sciences, Utrecht University, P.O. Box 80.021, 3508 TA Utrecht, The Netherlands
| | - Christina E Mueller
- Department of Ecosystem Studies, Royal Netherlands Institute for Sea Research (NIOZ-Yerseke), P.O. Box 140, 4400 AC Yerseke, The Netherlands
| | - Bart Veuger
- Department of Ecosystem Studies, Royal Netherlands Institute for Sea Research (NIOZ-Yerseke), P.O. Box 140, 4400 AC Yerseke, The Netherlands
| | - Ann I Larsson
- Dept. of Marine Sciences, Tjärnö, University of Gothenburg, 452 96 Strömstad, Sweden
| | - Armin Form
- GEOMAR, Helmholtz Centre for Ocean Research, Düsternbrooker Weg 20, 24105 Kiel, Germany
| | - Dick van Oevelen
- Department of Ecosystem Studies, Royal Netherlands Institute for Sea Research (NIOZ-Yerseke), P.O. Box 140, 4400 AC Yerseke, The Netherlands
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Shantz AA, Lemoine NP, Burkepile DE. Nutrient loading alters the performance of key nutrient exchange mutualisms. Ecol Lett 2015; 19:20-8. [PMID: 26549314 DOI: 10.1111/ele.12538] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 07/10/2015] [Accepted: 09/30/2015] [Indexed: 01/27/2023]
Abstract
Nutrient exchange mutualisms between phototrophs and heterotrophs, such as plants and mycorrhizal fungi or symbiotic algae and corals, underpin the functioning of many ecosystems. These relationships structure communities, promote biodiversity and help maintain food security. Nutrient loading may destabilise these mutualisms by altering the costs and benefits each partner incurs from interacting. Using meta-analyses, we show a near ubiquitous decoupling in mutualism performance across terrestrial and marine environments in which phototrophs benefit from enrichment at the expense of their heterotrophic partners. Importantly, heterotroph identity, their dependence on phototroph-derived C and the type of nutrient enrichment (e.g. nitrogen vs. phosphorus) mediated the responses of different mutualisms to enrichment. Nutrient-driven changes in mutualism performance may alter community organisation and ecosystem processes and increase costs of food production. Consequently, the decoupling of nutrient exchange mutualisms via alterations of the world's nitrogen and phosphorus cycles may represent an emerging threat of global change.
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Affiliation(s)
- Andrew A Shantz
- Department of Biology, Florida International University, Miami, FL, 33199, USA
| | - Nathan P Lemoine
- Department of Biology, Florida International University, Miami, FL, 33199, USA.,Department of Biology, Colorado State University, Fort Collins, CO, 80523, USA
| | - Deron E Burkepile
- Department of Biology, Florida International University, Miami, FL, 33199, USA.,Department of Ecology, Evolution, and Marine Biology, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
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Rädecker N, Pogoreutz C, Voolstra CR, Wiedenmann J, Wild C. Nitrogen cycling in corals: the key to understanding holobiont functioning? Trends Microbiol 2015; 23:490-7. [DOI: 10.1016/j.tim.2015.03.008] [Citation(s) in RCA: 233] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 03/08/2015] [Accepted: 03/18/2015] [Indexed: 01/11/2023]
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