Marine Science Program

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Now showing 1 - 5 of 1895
  • Article

    Responses of the coral reef cryptobiome to environmental gradients in the Red Sea

    (Public Library of Science (PLoS), 2024-04-16) Villalobos, Rodrigo; Aylagas, Eva; Ellis, Joanne I.; Pearman, John K.; Anlauf, Holger; Curdia, Joao; Lozano-Cortes, Diego; Mejia, Alejandro; Roth, Florian; Berumen, Michael L.; Carvalho, Susana; Red Sea Research Center; Red Sea Research Center (RSRC); Biological, Environmental Sciences and Engineering; Biological and Environmental Science and Engineering (BESE) Division; Marine Science; Marine Science Program; The Red Sea Development Company, AlRaidah Digital City, Saudi Arabia; School of Biological Sciences, Waikato University, Tauranga, New Zealand; Coastal and Freshwater Group, Cawthron Institute, Nelson, New Zealand; University of Seychelles and Blue Economy Research Institute Anse Royal, Victoria, Mahe, Seychelles; Saudi Aramco, Environmental Protection Department, Dhahran, Saudi Arabia; Stockholm University, Baltic Sea Centre, Stockholm, Sweden

    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.

  • Article

    Localization and symbiotic status of probiotics in the coral holobiont

    (American Society for Microbiology, 2024-04-12) Cardoso, Pedro M.; Hill, L. J.; Villela, Helena Dias Muller; Vilela, C. L. S.; Assis, J. M.; Rosado, P. M.; Rosado, J. G.; Chacon, M. A.; Majzoub, M. E.; Duarte, Gustavo; Thomas, T.; Peixoto, Raquel S.; Computational Biology Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia; Marine Science and Bioscience Programs, Biological, Environmental and Engineering Sciences Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia; Marine Science; Marine Science Program; Biological, Environmental Sciences and Engineering; Biological and Environmental Science and Engineering (BESE) Division; Red Sea Research Center; Red Sea Research Center (RSRC); Bioscience; Bioscience Program; Laboratory of Molecular Microbial Ecology, Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Center for Marine Science and Innovation; School of Biological, Earth and Environmental Sciences, The University of New South Wales, Sydney, New South Wales, Australia

    Corals establish symbiotic relationships with microorganisms, especially endosymbiotic photosynthetic algae. Although other microbes have been commonly detected in coral tissues, their identity and beneficial functions for their host are unclear. Here, we confirm the beneficial outcomes of the inoculation of bacteria selected as probiotics and use fluorescence in situ hybridization (FISH) to define their localization in the coral Pocillopora damicornis. Our results show the first evidence of the inherent presence of Halomonas sp. and Cobetia sp. in native coral tissues, even before their inoculation. Furthermore, the relative enrichment of these coral tissue-associated bacteria through their inoculation in corals correlates with health improvements, such as increases in photosynthetic potential, and productivity. Our study suggests the symbiotic status of Halomonas sp. and Cobetia sp. in corals by indicating their localization within coral gastrodermis and epidermis and correlating their increased relative abundance through active inoculation with beneficial outcomes for the holobiont. This knowledge is crucial to facilitate the screening and application of probiotics that may not be transient members of the coral microbiome.

  • Article

    Vertical and latitudinal distribution of bottom-up and top-down controls of heterotrophic prokaryotes in the Red Sea

    (Elsevier BV, 2024-04) Sabbagh, Eman; Ll. Calleja, Maria; Huete-Stauffer, Tamara; Daffonchio, Daniele; Moran, Xose Anxelu G.; Red Sea Research Center (RSRC), Division of Biological and Environmental Sciences and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), 23953 Thuwal, Saudi Arabia; Bioscience; Bioscience Program; Biological, Environmental Sciences and Engineering; Biological and Environmental Science and Engineering (BESE) Division; Red Sea Research Center; Red Sea Research Center (RSRC); Marine Science; Marine Science Program; Present address: Department of Marine and Coastal Conservation, National Center for Wildlife (NCW), 12411 Riyadh, Saudi Arabia; Marine Ecology and Systematics Group (MarES), Department of Biology, University of Balearic Islands (UIB), 07122 Palma de Mallorca, Spain; Spanish Institute of Oceanography (IEO), 33212 Gijón/Xixón, Spain

    Heterotrophic prokaryotes (HPs) represent the largest fraction of living biomass in the ocean. Comprehensively understanding the spatio-temporal variability of their controlling factors remains a challenge in microbial oceanography, especially in little explored low latitude regions such as the Red Sea, one of the hottest and saltiest basins on Earth. In this study, we assessed the vertical (5–1000 m) and latitudinal (16°-27° N) variations in HPs and their bottom-up (resource availability) and top-down controls (protistan grazing and viral lysis) at eight stations along the Red Sea, in three cruises carried out between 2017 and 2019. The decrease in HPs abundances with depth was less pronounced than that of heterotrophic nanoflagellates (HNFs) and viruses. We found that inorganic nutrient and dissolved organic carbon (DOC) concentrations do not vary significantly from north to south, thus suggesting a similar bottom-up control on HPs abundances along the latitudinal gradient. We found significant southward increase in the HP:HNF ratio (r = 0.56, p < 0.0001, n = 140), suggesting that HNFs have a lower impact on their HPs prey in the southern Red Sea. The preference of HNFs for larger HPs cells with depth was found only in the spring cruise. Viral abundances do not show any marked latitudinal gradient but show a significant positive relationship with HPs abundances in the water column in all seasons. The higher linear regression slope found in summer suggests that viruses are more important for HPs mortality in the warmer months. This study strengthens the importance of top-down controls in maintaining lower HPs stocks in the Red Sea and suggests that both latitudinal and seasonal variations have minor but measurable roles.

  • Article

    Consistent Symbiodiniaceae community assemblage in a mesophotic-specialist coral along the Saudi Arabian Red Sea

    (Frontiers Media SA, 2024-03-26) Vimercati, Silvia; Terraneo, Tullia Isotta; Castano, Carolina Bocanegra; Barreca, Federica; Hume, Benjamin C.C.; Marchese, Fabio; Ouhssain, Mustapha; Steckbauer, Alexandra; Chimienti, Giovanni; Eweida, Ameer A.; Voolstra, Christian R.; Rodrigue, Mattie; Pieribone, Vincent; Purkis, Sam J.; Qurban, Mohammed; Jones, Burton; Duarte, Carlos M.; Benzoni, Francesca; Marine Science; Marine Science Program; Biological, Environmental Sciences and Engineering; Biological and Environmental Science and Engineering (BESE) Division; Red Sea Research Center; Red Sea Research Center (RSRC); Computational Bioscience Research Center; Computational Bioscience Research Center (CBRC); Department of Biology, University of Konstanz, Konstanz, Germany; Consorzio Nazionale Interuniversitario per le Scienze del Mare (CoNISMa), Rome, Italy; Center of Carbonate Research, Department of Marine Geosciences, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, United States; Marine Conservation Program, NEOM, Saudi Arabia; OceanX, New York, NY, United States; Khaled bin Sultan Living Oceans Foundation, Annapolis, MD, United States; National Center for Wildlife Development, Riyadh, Saudi Arabia

    Introduction: The Red Sea is a narrow rift basin characterized by latitudinal environmental gradients which shape the diversity and distribution of reef-dwelling organisms. Studies on Symbiodiniaceae associated with select hard coral taxa present species- specific assemblages and concordant variation patterns from the North to southeast Red Sea coast at depths shallower than 30 m. At mesophotic depths, however, algal diversity studies are rare. Here, we characterize for the first-time host-associated algal communities of a mesophotic specialist coral species, Leptoseris cf. striatus, along the Saudi Arabian Red Sea coast. Methods: We sampled 56 coral colonies spanning the eastern Red Sea coastline from the Northern Red Sea to the Farasan Banks in the South, and across two sampling periods, Fall 2020 and Spring 2022. We used Next Generation Sequencing of the ITS2 marker region in conjunction with SymPortal to denote algal assemblages. Results and discussion: Our results show a relatively stable coral species-specific interaction with algae from the genus Cladocopium along the examined latitudinal gradient, with the appearance, in a smaller proportion, of presumed thermally tolerant algal taxa in the genera Symbiodinium and Durusdinium during the warmer season (Fall 2020). Contrary to shallow water corals, our results do not show a change in Symbiodiniaceae community composition from North to South in this mesophotic specialist species. However, our study highlights for the first time that symbiont communities are subject to change over time at mesophotic depth, which could represent an important phenomenon to address in future studies.

  • Article

    Metabolomics-based analysis of the diatom Cheatoceros tenuissimus combining NMR and GC–MS techniques

    (Elsevier BV, 2024-04-03) Alothman, Afrah; Emwas, Abdul-Hamid M.; Singh, Upendra; Jaremko, Mariusz; Agusti, Susana; King Abdullah University of Science and Technology (KAUST), Biological and Environmental and Science and Engineering, Marine Science Program, Thuwal, 23955-6900, Saudi Arabia; King Abdullah University of Science and Technology (KAUST), Core Labs, Thuwal, 23955-6900, Saudi Arabia; King Abdullah University of Science and Technology (KAUST), Biological and Environmental and Science and Engineering, Thuwal, 23955-6900, Saudi Arabia; Marine Science; Marine Science Program; Biological, Environmental Sciences and Engineering; Biological and Environmental Science and Engineering (BESE) Division; NMR; Bioscience; Bioscience Program; Red Sea Research Center; Red Sea Research Center (RSRC)

    Metabolomics, a recent addition to omics sciences, studies small molecules across plants, animals, humans, and marine organisms. Nuclear magnetic resonance (NMR) and gas chromatography-mass spectrometry (GC–MS) are widely used in those studies, including microalgae metabolomics. NMR is non-destructive and highly reproducible but has limited sensitivity, which could be supplemented by joining GC–MS analysis. Extracting metabolites from macromolecules requires optimization for trustworthy results. Different extraction methods yield distinct profiles, emphasizing the need for optimization. The results indicated that the optimized extraction procedure successfully identified NMR and GC–MS-based metabolites in MeOH, CHCl3, and H2O extraction solvents. The findings represented the spectral information related to carbohydrates, organic molecules, and amino acids from the water-soluble metabolites fraction and a series of fatty acid chains, lipids, and sterols from the lipid fraction. Our study underscores the benefit of combining NMR and GC–MS techniques to comprehensively understand microalgae metabolomes, including high and low metabolite concentrations and abundances. • In this study, we focused on optimizing the extraction procedure and combining NMR and GC–MS techniques to overcome the low NMR sensitivity and the different detected range limits of NMR and GC–MS. • We explored metabolome diversity in a tropical strain of the small cells’ diatom Cheatoceros tenuissimus.