1
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Banchi E, Manna V, Muggia L, Celussi M. Marine Fungal Diversity and Dynamics in the Gulf of Trieste (Northern Adriatic Sea). MICROBIAL ECOLOGY 2024; 87:78. [PMID: 38806848 PMCID: PMC11133070 DOI: 10.1007/s00248-024-02394-z] [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: 02/12/2024] [Accepted: 05/20/2024] [Indexed: 05/30/2024]
Abstract
Fungi contribute to different important ecological processes, including decomposition of organic matter and nutrient cycling, but in the marine environment the main factors influencing their diversity and dynamics at the spatial and temporal levels are still largely unclear. In this study, we performed DNA metabarcoding on seawater sampled monthly over a year and a half in the Gulf of Trieste (northern Adriatic Sea), targeting the internal transcribed spacer (ITS) and the 18S rRNA gene regions. The fungal communities were diverse, very dynamic, and belonged predominantly to marine taxa. Samples could be clustered in two groups, mainly based on the high (> 30%) or low relative proportion of the ascomycetes Parengyodontium album, which emerged as a key taxon in this area. Dissolved and particulate organic C:N ratio played important roles in shaping the mycoplankton assemblages, suggesting that differently bioavailable organic matter pools may be utilized by different consortia. The proportion of fungal over total reads was 31% for ITS and 0.7% for 18S. ITS had the highest taxonomic resolution but low power to detect early divergent fungal lineages. Our results on composition, distribution, and environmental drivers extended our knowledge of the structure and function of the mycobiome of coastal waters.
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Affiliation(s)
- Elisa Banchi
- National Institute of Oceanography and Applied Geophysics (OGS), Trieste, Italy.
- NBFC, National Biodiversity Future Center, Palermo, Italy.
| | - Vincenzo Manna
- National Institute of Oceanography and Applied Geophysics (OGS), Trieste, Italy
- NBFC, National Biodiversity Future Center, Palermo, Italy
| | - Lucia Muggia
- Department of Life Sciences, University of Trieste, Trieste, Italy
| | - Mauro Celussi
- National Institute of Oceanography and Applied Geophysics (OGS), Trieste, Italy
- NBFC, National Biodiversity Future Center, Palermo, Italy
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2
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Diver P, Ward BA, Cunliffe M. Physiological and morphological plasticity in response to nitrogen availability of a yeast widely distributed in the open ocean. FEMS Microbiol Ecol 2024; 100:fiae053. [PMID: 38599628 PMCID: PMC11062419 DOI: 10.1093/femsec/fiae053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 04/02/2024] [Accepted: 04/09/2024] [Indexed: 04/12/2024] Open
Abstract
Yeasts are prevalent in the open ocean, yet we have limited understanding of their ecophysiological adaptations, including their response to nitrogen availability, which can have a major role in determining the ecological potential of other planktonic microbes. In this study, we characterized the nitrogen uptake capabilities and growth responses of marine-occurring yeasts. Yeast isolates from the North Atlantic Ocean were screened for growth on diverse nitrogen substrates, and across a concentration gradient of three environmentally relevant nitrogen substrates: nitrate, ammonium, and urea. Three strains grew with enriched nitrate while two did not, demonstrating that nitrate utilization is present but not universal in marine yeasts, consistent with existing knowledge of nonmarine yeast strains. Naganishia diffluens MBA_F0213 modified the key functional trait of cell size in response to nitrogen concentration, suggesting yeast cell morphology changes along chemical gradients in the marine environment. Meta-analysis of the reference DNA barcode in public databases revealed that the genus Naganishia has a global ocean distribution, strengthening the environmental applicability of the culture-based observations. This study provides novel quantitative understanding of the ecophysiological and morphological responses of marine-derived yeasts to variable nitrogen availability in vitro, providing insight into the functional ecology of yeasts within pelagic open ocean environments.
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Affiliation(s)
- Poppy Diver
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth, PL1 2PB, United Kingdom
- School of Ocean and Earth Science, University of Southampton, Waterfront Campus, European Way, Southampton, SO14 3ZH, United Kingdom
| | - Ben A Ward
- School of Ocean and Earth Science, University of Southampton, Waterfront Campus, European Way, Southampton, SO14 3ZH, United Kingdom
| | - Michael Cunliffe
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth, PL1 2PB, United Kingdom
- School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, PL4 8AA, United Kingdom
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3
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Chen X, Xu G, Xiong P, Peng J, Fang K, Wan S, Wang B, Gu F, Li J, Xiong H. Dry and wet seasonal variations of the sediment fungal community composition in the semi-arid region of the Dali River, Northwest China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:123694-123709. [PMID: 37993647 DOI: 10.1007/s11356-023-31042-1] [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: 08/25/2023] [Accepted: 11/09/2023] [Indexed: 11/24/2023]
Abstract
Microbial communities play an important role in water quality regulation and biogeochemical cycling in freshwater ecosystems. However, there has been a lack of research on the seasonal variation of sediment microorganisms in the sediments of small river basins in typical semi-arid region. In this study, high-throughput DNA sequencing was used to investigate the fungal community and its influencing factors in the sediment of the Dali River in the dry and wet seasons. The results showed that there were obvious seasonal differences in fungal alpha diversity. The diversity and richness of fungi in the dry season were greater than that in the wet season, but the evenness of fungi in the dry season was lower than that in the wet season. In addition, Ascomycota and Basidiomycota were the most important phyla in the Dali River fungal community, but their distributions showed clear seasonal differences. In the dry season, the relative abundance of Ascomycota and Basidiomycota were 12.34-46.42% and 17.59-27.20%, respectively. In the wet season, the relative abundances of these two phyla were 24.33-36.56% and 5.75-12.26%, respectively. PICRUSt2 was used to predict the metabolic function of fungal community in the sediment, and it was found that at the first level, the proportion of biosynthesis in the dry season was higher than that in the wet season. The ecological network structure showed that the fungal community in the wet season was more complex and stable than that in the dry season. The characteristic fungi in the dry season sediment were chytrid fungi in the family Rhizophydiaceae and the order Rhizophydiales, whereas those in the wet season sediment were in the orders Eurotiales and Saccharomycetales. Canonical correspondence analysis (CCA) showed that the physicochemical properties of water and sediment together explained a greater proportion of the dry-season fungal community changes than of the wet-season changes. In the dry season, temperature and ammonia nitrogen in the water were the main factors affecting the change of fungal community, whereas in the wet season, total nitrogen concentration of the water, electrical conductivity, total organic carbon and available phosphorus of the sediment, pH, and temperature were the main factors affecting the changes in fungal community composition. The results of this study enhanced our understanding of microbial communities in semi-arid river ecosystems, and highlight the importance of the management and protection in river ecosystems.
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Affiliation(s)
- Xin Chen
- Key Laboratory of National Forestry Administration on Ecological Hydrology and Disaster Prevention in Arid Regions, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China
| | - Guoce Xu
- Key Laboratory of National Forestry Administration on Ecological Hydrology and Disaster Prevention in Arid Regions, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China.
| | - Ping Xiong
- Shaanxi Forestry Survey and Planning Institute, Xi'an, 710082, Shaanxi, China
| | - Jianbo Peng
- Shaanxi Forestry Survey and Planning Institute, Xi'an, 710082, Shaanxi, China
| | - Kang Fang
- Key Laboratory of National Forestry Administration on Ecological Hydrology and Disaster Prevention in Arid Regions, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China
| | - Shun Wan
- Key Laboratory of National Forestry Administration on Ecological Hydrology and Disaster Prevention in Arid Regions, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China
| | - Bin Wang
- Key Laboratory of National Forestry Administration on Ecological Hydrology and Disaster Prevention in Arid Regions, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China
| | - Fengyou Gu
- Key Laboratory of National Forestry Administration on Ecological Hydrology and Disaster Prevention in Arid Regions, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China
| | - Jing Li
- Key Laboratory of National Forestry Administration on Ecological Hydrology and Disaster Prevention in Arid Regions, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China
| | - Haijing Xiong
- Key Laboratory of National Forestry Administration on Ecological Hydrology and Disaster Prevention in Arid Regions, Xi'an University of Technology, Xi'an, 710048, Shaanxi, China
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4
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Zhang T, Ji Z, Chen X, Yu L. Shotgun metagenomics reveals a diverse mycobiome in the seawater from a High Arctic fjord (Kongsfjorden, Svalbard). ENVIRONMENTAL RESEARCH 2023; 233:116437. [PMID: 37331553 DOI: 10.1016/j.envres.2023.116437] [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: 04/18/2023] [Revised: 05/30/2023] [Accepted: 06/15/2023] [Indexed: 06/20/2023]
Abstract
In the Arctic fjords, the marine mycobiome experiences significant changes under environmental conditions driven by climate change. However, research on the ecological roles and the adaptive mechanisms of marine mycobiome in the Arctic fjord remains insufficiently explored. The present study employed shotgun metagenomics to comprehensively characterize the mycobiome in 24 seawater samples from Kongsfjorden, a High Arctic fjord situated in Svalbard. It revealed the presence of a diverse mycobiome with eight phyla, 34 classes, 71 orders, 152 families, 214 genera, and 293 species. The taxonomic and functional composition of the mycobiome differed significantly among the three layers, i.e., upper layer (depth of 0 m), middle layer (depths of 30-100 m), and lower layer (depths of 150-200 m). Several taxonomic groups (e.g., phylum Ascomycota, class Eurotiomycetes, order Eurotiales, family Aspergillaceae, and genus Aspergillus) and KOs (e.g., K03236/EIF1A, K03306/TC.PIT, K08852/ERN1, and K03119/tauD) were significantly distinct among the three layers. Among the measured environmental parameters, depth, NO2-, and PO43- were identified as the key factors influencing the mycobiome composition. Conclusively, our findings revealed that the mycobiome was diverse in the Arctic seawater and significantly impacted by the variability of environmental conditions in the High Arctic fjord. These results will assist future studies in exploring the ecological and adaptive responses towards the changes within the Arctic ecosystems.
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Affiliation(s)
- Tao Zhang
- China Pharmaceutical Culture Collection, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China.
| | - Zhongqiang Ji
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, PR China
| | - Xiufei Chen
- China Pharmaceutical Culture Collection, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
| | - Liyan Yu
- China Pharmaceutical Culture Collection, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China.
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5
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Breyer E, Baltar F. The largely neglected ecological role of oceanic pelagic fungi. Trends Ecol Evol 2023; 38:870-888. [PMID: 37246083 DOI: 10.1016/j.tree.2023.05.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 04/25/2023] [Accepted: 05/02/2023] [Indexed: 05/30/2023]
Abstract
Most investigations into ocean ecology and biogeochemistry have tended to focus on marine bacteria, archaea, and protists, while pelagic fungi (mycoplankton) have traditionally been neglected and considered to reside only in association with benthic solid substrates. Nevertheless, recent studies have revealed that pelagic fungi are distributed ubiquitously throughout the water column in every ocean basin and play an active role in the degradation of organic matter and the cycling of nutrients. We review the current status of knowledge on the ecology of mycoplankton and highlight knowledge gaps and challenges. These findings underscore the need to recognize this neglected kingdom as significant contributors to the organic matter cycling and ecology of the oceans.
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Affiliation(s)
- Eva Breyer
- Fungal and Biogeochemical Oceanography Group, Department of Functional and Evolutionary Ecology, University of Vienna, Djerassiplatz 1, 1030 Vienna, Austria.
| | - Federico Baltar
- Fungal and Biogeochemical Oceanography Group, Department of Functional and Evolutionary Ecology, University of Vienna, Djerassiplatz 1, 1030 Vienna, Austria.
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6
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Sen K, Bai M, Li J, Ding X, Sen B, Wang G. Spatial Patterns of Planktonic Fungi Indicate Their Potential Contributions to Biological Carbon Pump and Organic Matter Remineralization in the Water Column of South China Sea. J Fungi (Basel) 2023; 9:640. [PMID: 37367576 DOI: 10.3390/jof9060640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 05/25/2023] [Accepted: 05/29/2023] [Indexed: 06/28/2023] Open
Abstract
Fungi have long been known to be dynamic in coastal water columns with multiple trophic modes. However, little is known about their interactions with abiotic and biotic components, contribution to the biological carbon pump (BCP), and organic matter remineralization in the oceanic water column. In this study, we investigated how fungi vary spatially and how their variations relate to that of bacteria in the water column of the South China Sea (SCS). Fungi were about three orders less prevalent than bacteria, and the main factors influencing their distribution were depth, temperature, and distance from the sites of riverine inputs. The decline in the abundance of fungi with depth was less steep than that of bacteria. Correlation tests revealed a strong positive association between the abundance of fungi and bacteria, especially in the twilight (r = 0.62) and aphotic (r = 0.70) zones. However, the co-occurrence network revealed mutual exclusion between certain members of fungi and bacteria. The majority of fungi in the water column were saprotrophs, which indicated that they were generally involved in the degradation of organic matter, particularly in twilight and aphotic zones. Similar to bacteria, the involvement of fungi in the metabolism of carbohydrates, proteins, and lipids was predicted, pointing to their participation in the turnover of organic carbon and the biogeochemical cycling of carbon, nitrogen, and sulfur. These findings suggest that fungi play a role in BCP and support their inclusion in marine microbial ecosystem models.
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Affiliation(s)
- Kalyani Sen
- Centre for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Mohan Bai
- Centre for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Jiaqian Li
- Centre for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Xueyan Ding
- Centre for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Biswarup Sen
- Centre for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Guangyi Wang
- Centre for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin 300072, China
- Center for Biosafety Research and Strategy, Tianjin University, Tianjin 300072, China
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7
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Lauritano C, Galasso C. Microbial Interactions between Marine Microalgae and Fungi: From Chemical Ecology to Biotechnological Possible Applications. Mar Drugs 2023; 21:md21050310. [PMID: 37233504 DOI: 10.3390/md21050310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 05/17/2023] [Accepted: 05/17/2023] [Indexed: 05/27/2023] Open
Abstract
Chemical interactions have been shown to regulate several marine life processes, including selection of food sources, defense, behavior, predation, and mate recognition. These chemical communication signals have effects not only at the individual scale, but also at population and community levels. This review focuses on chemical interactions between marine fungi and microalgae, summarizing studies on compounds synthetized when they are cultured together. In the current study, we also highlight possible biotechnological outcomes of the synthetized metabolites, mainly for human health applications. In addition, we discuss applications for bio-flocculation and bioremediation. Finally, we point out the necessity of further investigating microalgae-fungi chemical interactions because it is a field still less explored compared to microalga-bacteria communication and, considering the promising results obtained until now, it is worthy of further research for scientific advancement in both ecology and biotechnology fields.
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Affiliation(s)
- Chiara Lauritano
- Department of Ecosustainable Marine Biotechnology, Stazione Zoologica Anton Dohrn, Via Acton n. 55, 80133 Naples, Italy
| | - Christian Galasso
- Department of Ecosustainable Marine Biotechnology, Calabria Marine Centre, Stazione Zoologica Anton Dohrn, C. da Torre Spaccata, 87071 Amendolara, Italy
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8
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Breyer E, Espada-Hinojosa S, Reitbauer M, Karunarathna SC, Baltar F. Physiological Properties of Three Pelagic Fungi Isolated from the Atlantic Ocean. J Fungi (Basel) 2023; 9:jof9040439. [PMID: 37108894 PMCID: PMC10143427 DOI: 10.3390/jof9040439] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 03/29/2023] [Accepted: 03/30/2023] [Indexed: 04/07/2023] Open
Abstract
Oceanic fungi are widely understudied compared to their terrestrial counterparts. However, they have been shown to be important degraders of organic matter in the global pelagic oceans. By examining the physiological characteristics of fungi isolated from the pelagic waters of the ocean it is possible to infer specific functions of each species in the biogeochemical processes that occur in the marine ecosystem. In this study, we isolated three pelagic fungi from different stations and depths across a transect in the Atlantic Ocean. We identified two yeasts [(Scheffersomyces spartinae (Debaryomycetaceae, Saccharomycetes, Ascomycota) and Rhodotorula sphaerocarpa (Sporidiobolaceae, Microbotryomycetes, Basidiomycota)], and the hyphae-morphotype fungus Sarocladium kiliense (Hypocreales, Sordariomycetes, Ascomycota), and conducted physiological experiments to investigate their preferred carbon uptake as well as their growth patterns under different environmental conditions. Despite their taxonomic and morphological differences, all species exhibited a high tolerance towards a wide range of salinities (0–40 g/L) and temperatures (5–35 °C). Furthermore, a shared metabolic preference for oxidizing amino acids was found among all fungal isolates. Collectively, this study provides relevant information on the physiological properties of oceanic pelagic fungi, revealing a high tolerance towards salinity and temperature changes, ultimately contributing to understanding their ecology and distribution in the oceanic water column.
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Affiliation(s)
- Eva Breyer
- Department of Functional and Evolutionary Ecology, University of Vienna, 1030 Vienna, Austria
| | | | - Magdalena Reitbauer
- Department of Functional and Evolutionary Ecology, University of Vienna, 1030 Vienna, Austria
| | - Samantha C. Karunarathna
- Center for Yunnan Plateau Biological Resources Protection and Utilization, Yunnan Engineering Research Center of Fruit Wine, College of Biological Resource and Food Engineering, Qujing Normal University, Qujing 655011, China
| | - Federico Baltar
- Department of Functional and Evolutionary Ecology, University of Vienna, 1030 Vienna, Austria
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9
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Chrismas N, Allen R, Allen MJ, Bird K, Cunliffe M. A 17-year time-series of fungal environmental DNA from a coastal marine ecosystem reveals long-term seasonal-scale and inter-annual diversity patterns. Proc Biol Sci 2023; 290:20222129. [PMID: 36722076 PMCID: PMC9890122 DOI: 10.1098/rspb.2022.2129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Changing patterns in diversity are a feature of many habitats, with seasonality a major driver of ecosystem structure and function. In coastal marine plankton-based ecosystems, seasonality has been established through long-term time-series of bacterioplankton and protists. Alongside these groups, fungi also inhabit coastal marine ecosystems. If and how marine fungi show long-term intra- and inter-annual diversity patterns is unknown, preventing a comprehensive understanding of marine fungal ecology. Here, we use a 17-year environmental DNA time-series from the English Channel to determine long-term marine fungal diversity patterns. We show that fungal community structure progresses at seasonal and monthly scales and is only weakly related to environmental parameters. Communities restructured every 52-weeks suggesting long-term stability in diversity patterns. Some major marine fungal genera have clear inter-annual recurrence patterns, re-appearing in the annual cycle at the same period. Low relative abundance taxa that are likely non-marine show seasonal input to the coastal marine ecosystem suggesting land-sea exchange regularly takes place. Our results demonstrate long-term intra- and inter-annual marine fungal diversity patterns. We anticipate this study could form the basis for better understanding the ecology of marine fungi and how they fit in the structure and function of the wider coastal marine ecosystem.
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Affiliation(s)
- Nathan Chrismas
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
| | - Ro Allen
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
| | - Michael J. Allen
- College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4PY, UK,Plymouth Marine Laboratory, Prospect Place, Plymouth PL1 3DH, UK
| | - Kimberley Bird
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
| | - Michael Cunliffe
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK,School of Biological and Marine Sciences, University of Plymouth, Plymouth PL4 8AA, UK
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10
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Different Geographic Strains of Dinoflagellate Karlodinium veneficum Host Highly Diverse Fungal Community and Potentially Serve as Possible Niche for Colonization of Fungal Endophytes. Int J Mol Sci 2023; 24:ijms24021672. [PMID: 36675187 PMCID: PMC9865425 DOI: 10.3390/ijms24021672] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 01/03/2023] [Accepted: 01/08/2023] [Indexed: 01/18/2023] Open
Abstract
In numerous studies, researchers have explored the interactions between fungi and their hosting biota in terrestrial systems, while much less attention has been paid to the counterpart interactions in aquatic, and particularly marine, ecosystems. Despite the growing recognition of the potential functions of fungi in structuring phytoplankton communities, the current insights were mostly derived from phytoplankton hosts, such as diatoms, green microalgae, and cyanobacteria. Dinoflagellates are the second most abundant group of phytoplankton in coastal marine ecosystems, and they are notorious for causing harmful algal blooms (HABs). In this study, we used high-throughput amplicon sequencing to capture global snapshots of specific fungal assemblages associated with laboratory-cultured marine dinoflagellate. We investigated a total of 13 clonal cultures of the dinoflagellate Karlodinium veneficum that were previously isolated from 5 geographic origins and have been maintained in our laboratory from several months to more than 14 years. The total recovered fungal microbiome, which consisted of 349 ASVs (amplicon sequencing variants, sequences clustered at a 100% sequence identity), could be assigned to 4 phyla, 18 classes, 37 orders, 65 families, 97 genera, and 131 species. The fungal consortium displayed high diversity and was dominated by filamentous fungi and ascomycetous and basidiomycetous yeasts. A core set of three genera among all the detected fungi was constitutively present in the K. veneficum strains isolated from geographically distant regions, with the top two most abundant genera, Thyridium and Pseudeurotium, capable of using hydrocarbons as the sole or major source of carbon and energy. In addition, fungal taxa previously documented as endophytes in other hosts were also found in all tested strains of K. veneficum. Because host-endophyte interactions are highly variable and strongly case-dependent, these fungal taxa were not necessarily genuine endosymbionts of K. veneficum; instead, it raised the possibility that dinoflagellates could potentially serve as an alternative ecological niche for the colonization of fungal endophytes. Our findings lay the foundation for further investigations into the potential roles or functions of fungi in the regulation of the growth dynamics and HABs of marine dinoflagellates in the field.
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11
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Lee JW, Seo CW, Lee W, Kim JS, Park KH, Cho Y, Lim YW. Diversity and Dynamics of Marine Arenicolous Fungi in Three Seasides of the Korean Peninsula. J Microbiol 2023; 61:63-82. [PMID: 36715871 DOI: 10.1007/s12275-023-00011-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Accepted: 12/13/2022] [Indexed: 01/31/2023]
Abstract
Various arenicolous fungal species have been detected from the beach sand in the coastal area. However, little has been revealed regarding their distribution and dynamics. To investigate the overall diversity of marine arenicolous fungi (MAFs) in Korea and whether the composition of MAFs is affected by ocean currents, we isolated and analyzed the fungal community from the western, southern, and eastern seasides of the Korean Peninsula. In total, 603 strains were isolated and identified as 259 species based on appropriate molecular markers for each genus (ITS, BenA, CaM, tef1, and act). The composition of MAFs showed differences among the seasides. Our results indicate that many MAFs inhabit the beach sand on the Korean Peninsula, and the composition of MAFs is also affected by ocean currents flowing along each coast.
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Affiliation(s)
- Jun Won Lee
- School of Biological Sciences and Institution of Microbiology, Seoul National University, Seoul, 08826, Republic of Korea
| | - Chang Wan Seo
- School of Biological Sciences and Institution of Microbiology, Seoul National University, Seoul, 08826, Republic of Korea
| | - Wonjun Lee
- School of Biological Sciences and Institution of Microbiology, Seoul National University, Seoul, 08826, Republic of Korea
| | - Ji Seon Kim
- School of Biological Sciences and Institution of Microbiology, Seoul National University, Seoul, 08826, Republic of Korea
| | - Ki Hyeong Park
- School of Biological Sciences and Institution of Microbiology, Seoul National University, Seoul, 08826, Republic of Korea
| | - Yoonhee Cho
- School of Biological Sciences and Institution of Microbiology, Seoul National University, Seoul, 08826, Republic of Korea
| | - Young Woon Lim
- School of Biological Sciences and Institution of Microbiology, Seoul National University, Seoul, 08826, Republic of Korea.
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12
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Cunliffe M. Who are the marine fungi? Environ Microbiol 2023; 25:131-134. [PMID: 36217720 PMCID: PMC10092172 DOI: 10.1111/1462-2920.16240] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 10/09/2022] [Indexed: 01/21/2023]
Affiliation(s)
- Michael Cunliffe
- Marine Biological Association, Plymouth, UK.,School of Biological and Marine Sciences, University Plymouth, Plymouth, UK
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13
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Glycoside hydrolase from the GH76 family indicates that marine Salegentibacter sp. Hel_I_6 consumes alpha-mannan from fungi. THE ISME JOURNAL 2022; 16:1818-1830. [PMID: 35414716 PMCID: PMC9213526 DOI: 10.1038/s41396-022-01223-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 02/10/2022] [Accepted: 03/11/2022] [Indexed: 11/08/2022]
Abstract
AbstractMicrobial glycan degradation is essential to global carbon cycling. The marine bacterium Salegentibacter sp. Hel_I_6 (Bacteroidota) isolated from seawater off Helgoland island (North Sea) contains an α-mannan inducible gene cluster with a GH76 family endo-α-1,6-mannanase (ShGH76). This cluster is related to genetic loci employed by human gut bacteria to digest fungal α-mannan. Metagenomes from the Hel_I_6 isolation site revealed increasing GH76 gene frequencies in free-living bacteria during microalgae blooms, suggesting degradation of α-1,6-mannans from fungi. Recombinant ShGH76 protein activity assays with yeast α-mannan and synthetic oligomannans showed endo-α-1,6-mannanase activity. Resolved structures of apo-ShGH76 (2.0 Å) and of mutants co-crystalized with fungal mannan-mimicking α-1,6-mannotetrose (1.90 Å) and α-1,6-mannotriose (1.47 Å) retained the canonical (α/α)6 fold, despite low identities with sequences of known GH76 structures (GH76s from gut bacteria: <27%). The apo-form active site differed from those known from gut bacteria, and co-crystallizations revealed a kinked oligomannan conformation. Co-crystallizations also revealed precise molecular-scale interactions of ShGH76 with fungal mannan-mimicking oligomannans, indicating adaptation to this particular type of substrate. Our data hence suggest presence of yet unknown fungal α-1,6-mannans in marine ecosystems, in particular during microalgal blooms.
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Roik A, Reverter M, Pogoreutz C. A roadmap to understanding diversity and function of coral reef-associated fungi. FEMS Microbiol Rev 2022; 46:6615459. [PMID: 35746877 PMCID: PMC9629503 DOI: 10.1093/femsre/fuac028] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 06/01/2022] [Accepted: 06/14/2022] [Indexed: 01/09/2023] Open
Abstract
Tropical coral reefs are hotspots of marine productivity, owing to the association of reef-building corals with endosymbiotic algae and metabolically diverse bacterial communities. However, the functional importance of fungi, well-known for their contribution to shaping terrestrial ecosystems and global nutrient cycles, remains underexplored on coral reefs. We here conceptualize how fungal functional traits may have facilitated the spread, diversification, and ecological adaptation of marine fungi on coral reefs. We propose that functions of reef-associated fungi may be diverse and go beyond their hitherto described roles of pathogens and bioeroders, including but not limited to reef-scale biogeochemical cycles and the structuring of coral-associated and environmental microbiomes via chemical mediation. Recent technological and conceptual advances will allow the elucidation of the physiological, ecological, and chemical contributions of understudied marine fungi to coral holobiont and reef ecosystem functioning and health and may help provide an outlook for reef management actions.
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Affiliation(s)
- Anna Roik
- Corresponding author: Helmholtz Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB), Ammerländer Heerstrasse 231, D-26129 Oldenburg, Germany. E-mail:
| | - Miriam Reverter
- Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky University of Oldenburg, Wilhelmshaven, 26046, Germany,School of Biological and Marine Sciences, University of Plymouth, Plymouth PL4 8AA, United Kingdom
| | - Claudia Pogoreutz
- Corresponding author: Laboratory for Biological Geochemistry, School of Architecture, Civil and Environmental Engineering, Ecole Polytechnique Federale de Lausanne (EPFL), 1015 Lausanne, Switzerland.,
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15
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Yao Y, Zhao J, Miao L, Hou J. Effects of sediment physicochemical factors and heavy metals on the diversity, structure, and functions of bacterial and fungal communities from a eutrophic river. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 303:119129. [PMID: 35283203 DOI: 10.1016/j.envpol.2022.119129] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 02/28/2022] [Accepted: 03/09/2022] [Indexed: 06/14/2023]
Abstract
Urbanization has destroyed river ecosystems, leading to eutrophication. Heavy metals are frequently observed in urban rivers, and the joint effects of eutrophication and heavy metals on microbial communities, especially on fungal communities, have not been adequately explored. In this study, we explored the effect of sediment physicochemical factors and heavy metals on the microbial diversity, community structure, and functions of bacterial and fungal communities from a black-odorous river in Wuhu, China. Twenty-four samples were collected, and the diversity and structure of fungal and bacterial communities were determined by high-throughput sequencing. Proteobacteria and Rozellomycota were the main phyla in the bacterial and fungal communities, respectively. The results showed different distribution patterns of bacterial and fungal communities along the river. Physicochemical factors and heavy metals exhibited different effects on microbial variation. Specifically, pH and Cr negatively affected bacterial α-diversity, whereas total phosphorus and Cr significantly affected fungal α-diversity. Variance partitioning analysis revealed that physicochemical factors explained more of the bacterial community structure than heavy metals (49.5% vs. 36.6%), with pH and total phosphorus being the dominant factors. Opposite patterns were observed for fungal community structure, with heavy metals contributing the most (48.0%). A similar influence pattern was observed for the predicted functions of the two communities. This study suggests that heavy metals in eutrophication rivers are essential factors that shift the microbial variation and should be considered in urban river evaluation and remediation.
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Affiliation(s)
- Yu Yao
- School of Environment, Nanjing Normal University, Nanjing, 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing, 210023, China; Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing Normal University, Nanjing, 210023, China
| | - Jiaqi Zhao
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
| | - Lingzhan Miao
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
| | - Jun Hou
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China.
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16
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Extracellular Enzymatic Activities of Oceanic Pelagic Fungal Strains and the Influence of Temperature. J Fungi (Basel) 2022; 8:jof8060571. [PMID: 35736054 PMCID: PMC9225461 DOI: 10.3390/jof8060571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 05/23/2022] [Accepted: 05/23/2022] [Indexed: 11/20/2022] Open
Abstract
Although terrestrial and aquatic fungi are well-known decomposers of organic matter, the role of marine fungi remains largely unknown. Recent studies based on omics suggest that marine fungi potentially play a major role in elemental cycles. However, there is very limited information on the diversity of extracellular enzymatic activities performed by pelagic fungi in the ocean and how these might be affected by community composition and/or critical environmental parameters such as temperature. In order to obtain information on the potential metabolic activity of marine fungi, extracellular enzymatic activities (EEA) were investigated. Five marine fungal species belonging to the most abundant pelagic phyla (Ascomycota and Basidiomycota) were grown at 5 °C and 20 °C, and fluorogenic enzymatic assays were performed using six substrate analogues for the hydrolysis of carbohydrates (β-glucosidase, β-xylosidase, and N-acetyl-β-D-glucosaminidase), amino acids (leucine aminopeptidase), and of organic phosphorus (alkaline phosphatase) and sulfur compounds (sulfatase). Remarkably, all fungal strains were capable of hydrolyzing all the offered substrates. However, the hydrolysis rate (Vmax) and half-saturation constant (Km) varied among the fungal strains depending on the enzyme type. Temperature had a strong impact on the EEAs, resulting in Q10 values of up to 6.1 and was species and substrate dependent. The observed impact of temperature on fungal EEA suggests that warming of the global ocean might alter the contribution of pelagic fungi in marine biogeochemical cycles.
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Sen K, Sen B, Wang G. Diversity, Abundance, and Ecological Roles of Planktonic Fungi in Marine Environments. J Fungi (Basel) 2022; 8:jof8050491. [PMID: 35628747 PMCID: PMC9147564 DOI: 10.3390/jof8050491] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 05/03/2022] [Accepted: 05/04/2022] [Indexed: 02/07/2023] Open
Abstract
Fungi are considered terrestrial and oceans are a “fungal desert”. However, with the considerable progress made over past decades, fungi have emerged as morphologically, phylogenetically, and functionally diverse components of the marine water column. Although their communities are influenced by a plethora of environmental factors, the most influential include salinity, temperature, nutrients, and dissolved oxygen, suggesting that fungi respond to local environmental gradients. The biomass carbon of planktonic fungi exhibits spatiotemporal dynamics and can reach up to 1 μg CL−1 of seawater, rivaling bacteria on some occasions, which suggests their active and important role in the water column. In the nutrient-rich coastal water column, there is increasing evidence for their contribution to biogeochemical cycling and food web dynamics on account of their saprotrophic, parasitic, hyper-parasitic, and pathogenic attributes. Conversely, relatively little is known about their function in the open-ocean water column. Interestingly, methodological advances in sequencing and omics approach, the standardization of sequence data analysis tools, and integration of data through network analyses are enhancing our current understanding of the ecological roles of these multifarious and enigmatic members of the marine water column. This review summarizes the current knowledge of the diversity and abundance of planktonic fungi in the world’s oceans and provides an integrated and holistic view of their ecological roles.
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Affiliation(s)
- Kalyani Sen
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Biswarup Sen
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Guangyi Wang
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin 300072, China
- Center for Biosafety Research and Strategy, Tianjin University, Tianjin 300072, China
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18
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Wu JY, Hua ZL, Gu L, Li XQ, Gao C, Liu YY. Perfluorinated compounds (PFCs) in regional industrial rivers: Interactions between pollution flux and eukaryotic community phylosymbiosis. ENVIRONMENTAL RESEARCH 2022; 203:111876. [PMID: 34400162 DOI: 10.1016/j.envres.2021.111876] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/21/2021] [Accepted: 08/09/2021] [Indexed: 06/13/2023]
Abstract
Perfluorinated compounds (PFCs) pose serious threats to aquatic ecosystems, especially their microbial communities. However, little is known about the phylosymbiosis of aquatic fungal and viridiplantae communities in response to PFC accumulation. We quantified the distribution of 14 PFCs in rivers and found that PFBA was dominant in the transition from water to sediment. High through-put sequencing revealed that phyla Ascomycota, Basidiomycota, Anthophyta, and Chlorophyta were the predominant in eukaryotic community. The effects of PFCs on spatial community coalescence at taxonomic and phylogenetic levels (p < 0.05) were revealed. Fungal community coalescence triggered the spatial assembly of fungal and viridiplantae communities in riverine environments (p < 0.05). Null modeling indicated that PFBA, PFTrDA and PFOS, etc, mediated phylogenetic assembly (p < 0.05) and stochastic processes (86.67-100%) maintain phylogenetic turnover in the fungal community. Meanwhile, variable selection (27.78-54.44%) explained the viridiplantae community assemblage. Finally, we identified fungal genera Hannaella, Naganishia, Purpureocillium and Stachybotrys as indicators for PFC pollution (p < 0.001). These results help explain the effects of PFCs on riverine ecological remediation.
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Affiliation(s)
- Jian-Yi Wu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China; Yangtze Institute for Conservation and Development, Hohai University, Jiangsu, 210098, China
| | - Zu-Lin Hua
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China; Yangtze Institute for Conservation and Development, Hohai University, Jiangsu, 210098, China
| | - Li Gu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China; Yangtze Institute for Conservation and Development, Hohai University, Jiangsu, 210098, China.
| | - Xiao-Qing Li
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China; Yangtze Institute for Conservation and Development, Hohai University, Jiangsu, 210098, China
| | - Chang Gao
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China; Yangtze Institute for Conservation and Development, Hohai University, Jiangsu, 210098, China
| | - Yuan-Yuan Liu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China; Yangtze Institute for Conservation and Development, Hohai University, Jiangsu, 210098, China
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19
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Pham TT, Dinh KV, Nguyen VD. Biodiversity and Enzyme Activity of Marine Fungi with 28 New Records from the Tropical Coastal Ecosystems in Vietnam. MYCOBIOLOGY 2021; 49:559-581. [PMID: 35035248 PMCID: PMC8725946 DOI: 10.1080/12298093.2021.2008103] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 11/09/2021] [Accepted: 11/15/2021] [Indexed: 06/14/2023]
Abstract
The coastal marine ecosystems of Vietnam are one of the global biodiversity hotspots, but the biodiversity of marine fungi is not well known. To fill this major gap of knowledge, we assessed the genetic diversity (ITS sequence) of 75 fungal strains isolated from 11 surface coastal marine and deeper waters in Nha Trang Bay and Van Phong Bay using a culture-dependent approach and 5 OTUs (Operational Taxonomic Units) of fungi in three representative sampling sites using next-generation sequencing. The results from both approaches shared similar fungal taxonomy to the most abundant phylum (Ascomycota), genera (Candida and Aspergillus) and species (Candida blankii) but were different at less common taxa. Culturable fungal strains in this study belong to 3 phyla, 5 subdivisions, 7 classes, 12 orders, 17 families, 22 genera and at least 40 species, of which 29 species have been identified and several species are likely novel. Among identified species, 12 and 28 are new records in global and Vietnamese marine areas, respectively. The analysis of enzyme activity and the checklist of trophic mode and guild assignment provided valuable additional biological information and suggested the ecological function of planktonic fungi in the marine food web. This is the largest dataset of marine fungal biodiversity on morphology, phylogeny and enzyme activity in the tropical coastal ecosystems of Vietnam and Southeast Asia. Biogeographic aspects, ecological factors and human impact may structure mycoplankton communities in such aquatic habitats.
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Affiliation(s)
- Thu Thuy Pham
- Institute of Biotechnology and Environment, Nha Trang University, Nha Trang, Vietnam
| | - Khuong V. Dinh
- Institute of Aquaculture, Nha Trang University, Nha Trang, Vietnam
| | - Van Duy Nguyen
- Institute of Biotechnology and Environment, Nha Trang University, Nha Trang, Vietnam
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20
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Patchy Distributions and Distinct Niche Partitioning of Mycoplankton Populations across a Nearshore to Open Ocean Gradient. Microbiol Spectr 2021; 9:e0147021. [PMID: 34908435 PMCID: PMC8672894 DOI: 10.1128/spectrum.01470-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Evidence increasingly suggests planktonic fungi (or mycoplankton) play an important role in marine food webs and biogeochemical cycles. In order to better understand their ecological role and how oceanographic gradients from the coastal to open ocean shape the mycoplankton community, molecular approaches were used to study fungal dynamics along a repeatedly sampled, five-station transect beginning at the mouth of an estuary and continuing 87 km across the continental shelf to the oligotrophic waters at the boundary of the Sargasso Sea. Similar to patterns in chlorophyll a, fungal 18S rRNA gene abundance showed a sharp decrease from nearshore to offshore stations. While Shannon's diversity was not statistically different across the transect, nonmetric multidimensional scaling (NMDS) ordination revealed that fungal communities at the nearshore station were significantly different from those at other stations. Even though spatial gradients were consistently strong, the shelf mycoplankton were more similar to those of the offshore communities when temperature was high (>20°C) and while they shifted toward the nearshore communities when temperature was low (<19°C), suggesting a role for additional seasonal factors (such as temperature) in shaping mycoplankton distributions. However, overall phylotype distributions were patchy with few taxa observed at all stations and the majority observed at a single station with the nearshore station exhibiting the largest number of exclusive phylotypes. Overall, our findings revealed the patchy spatial distributions and distinct niche partitioning of mycoplankton populations across a nearshore to open ocean gradient, which improved our understanding of fungal ecology in coastal waters. IMPORTANCE Fungi are an important, but understudied, group of heterotrophic microbes in marine environments. Traditionally, fungi in the coastal ocean were largely assumed to be derived from terrestrial inputs. Yet here we find many fungal taxa are endemic to the open ocean environment but are rare or absent in nearshore waters, suggesting they are not washed into the ocean from the land. As observed for the bacterioplankton, coastal oceanographic gradients can function as habitat barriers to partition fungal communities. Compared to the bacterioplankton, however, the mycoplankton exhibit a much patchier distribution pattern, suggesting differential drivers and the potential for spatially/temporally limited habitats or strong density-dependent selection. Therefore, our results show that mycoplankton in the coastal ocean may play a significant but complementary role to that of the bacterioplankton.
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21
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Thomas F, Le Duff N, Wu TD, Cébron A, Uroz S, Riera P, Leroux C, Tanguy G, Legeay E, Guerquin-Kern JL. Isotopic tracing reveals single-cell assimilation of a macroalgal polysaccharide by a few marine Flavobacteria and Gammaproteobacteria. THE ISME JOURNAL 2021; 15:3062-3075. [PMID: 33953365 PMCID: PMC8443679 DOI: 10.1038/s41396-021-00987-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 03/25/2021] [Accepted: 04/09/2021] [Indexed: 02/03/2023]
Abstract
Algal polysaccharides constitute a diverse and abundant reservoir of organic matter for marine heterotrophic bacteria, central to the oceanic carbon cycle. We investigated the uptake of alginate, a major brown macroalgal polysaccharide, by microbial communities from kelp-dominated coastal habitats. Congruent with cell growth and rapid substrate utilization, alginate amendments induced a decrease in bacterial diversity and a marked compositional shift towards copiotrophic bacteria. We traced 13C derived from alginate into specific bacterial incorporators and quantified the uptake activity at the single-cell level, using halogen in situ hybridization coupled to nanoscale secondary ion mass spectrometry (HISH-SIMS) and DNA stable isotope probing (DNA-SIP). Cell-specific alginate uptake was observed for Gammaproteobacteria and Flavobacteriales, with carbon assimilation rates ranging from 0.14 to 27.50 fg C µm-3 h-1. DNA-SIP revealed that only a few initially rare Flavobacteriaceae and Alteromonadales taxa incorporated 13C from alginate into their biomass, accounting for most of the carbon assimilation based on bulk isotopic measurements. Functional screening of metagenomic libraries gave insights into the genes of alginolytic Alteromonadales active in situ. These results highlight the high degree of niche specialization in heterotrophic communities and help constraining the quantitative role of polysaccharide-degrading bacteria in coastal ecosystems.
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Affiliation(s)
- François Thomas
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff (SBR), Roscoff, France.
| | - Nolwen Le Duff
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff (SBR), Roscoff, France
| | - Ting-Di Wu
- Institut Curie, Université Paris-Saclay, Paris, France
- Université Paris-Saclay, INSERM US43, CNRS UMS2016, Multimodal Imaging Center, Orsay, France
| | | | - Stéphane Uroz
- Université de Lorraine, INRAE, UMR1136 « Interactions Arbres-Microorganismes », Champenoux, France
| | - Pascal Riera
- Sorbonne Université, CNRS, UMR7144, Station Biologique de Roscoff (SBR), Roscoff, France
| | - Cédric Leroux
- CNRS, Sorbonne Université, FR2424, Metabomer, Station Biologique de Roscoff, Roscoff, France
| | - Gwenn Tanguy
- CNRS, Sorbonne Université, FR2424, Genomer, Station Biologique de Roscoff, Roscoff, France
| | - Erwan Legeay
- CNRS, Sorbonne Université, FR2424, Genomer, Station Biologique de Roscoff, Roscoff, France
| | - Jean-Luc Guerquin-Kern
- Institut Curie, Université Paris-Saclay, Paris, France
- Université Paris-Saclay, INSERM US43, CNRS UMS2016, Multimodal Imaging Center, Orsay, France
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22
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Sen K, Bai M, Sen B, Wang G. Disentangling the structure and function of mycoplankton communities in the context of marine environmental heterogeneity. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 766:142635. [PMID: 33071110 DOI: 10.1016/j.scitotenv.2020.142635] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/23/2020] [Accepted: 09/26/2020] [Indexed: 06/11/2023]
Abstract
Mycoplankton are a diverse and ubiquitous component of marine environments with a suggested role in ocean biogeochemical cycling. Thus far, the patterns of their abundance, structure, and function against spatial environmental heterogeneity remains poorly understood. Based on in silico and experimental evaluation of multiple markers, we adopted the ITS1 region to determine the composition, guilds, and metabolic potential of mycoplankton communities in contrasting marine environments. The trophic status of estuarine (SB1 and SB2) and coastal (DB1 and DB2) sites, but not oceanic (OS) site, was the major factor that determined their abundances. While ascomycetous fungi dominated the estuarine and coastal sites, basidiomycetous fungi were found to dominate the oceanic site. The zoosporic fungi were relatively more abundant in SB1 and DB2 sites compared to the other sites. The relative abundances of the core fungi, namely Cystobasidium, Phlebia, Rhodotorula, Trichoderma, Alternaria, Penicillium, Malassezia, and Aspergillus varied widely across the sites. Additionally, several fungal genera unique to each site were also identified. DB2 site exhibited the lowest fungal richness while the OS site the highest. Conversely, the diversity and evenness were the lowest for the OS site but highest for the SB1 site. Temperature, pH, and chlorophyll-a were strongly associated with spatial diversity patterns. Of the 11 assigned guilds, some guilds particularly were not detected, including plant pathogen-wood saprotroph in DB2, the endophyte-plant pathogen in OS, the animal pathogen in SB1, and fungal parasite in DB1 and SB2. Within core functions-metabolism of amino acids, carbohydrates and energy, fatty acids and lipids, nitrogen, sulfur, and other compounds-several pathways showed spatial variations. Overall, this study not just broadens the taxonomic and metabolic repertoire of marine mycoplankton but also provides the first evidence of how these are shaped by site-scale environmental heterogeneity.
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Affiliation(s)
- Kalyani Sen
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Mohan Bai
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Biswarup Sen
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Guangyi Wang
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin 300072, China; Qingdao Institute Ocean Engineering of Tianjin University, Qingdao 266237, China.
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23
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Zhang Z, Deng Q, Cao X, Zhou Y, Song C. Patterns of Sediment Fungal Community Dependent on Farming Practices in Aquaculture Ponds. Front Microbiol 2021; 12:542064. [PMID: 33679624 PMCID: PMC7933557 DOI: 10.3389/fmicb.2021.542064] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 01/26/2021] [Indexed: 01/01/2023] Open
Abstract
Despite fungi playing an important role in nutrient decomposition in aquatic ecosystems and being considered as vital actors in the ecological processes, they received limited attention regarding the community in aquaculture pond sediments which are extremely important and typically disturbed habitats. Using an ITS1 region of fungal rDNA, this study aimed to investigate sediment fungal communities in fish, crab, and crayfish ponds for decades of farming practices at representative aquaculture regions in the middle Yangtze River basin, China. We then aimed to explore the community patterns associated with species-based farming practices in the ponds at 18 farms. The results showed that the pond sediments harbored more than 9,000 operational taxonomic units. The sediments had significantly higher alpha diversity in crab ponds compared to that in fish and crayfish ponds. The fungal phyla largely belonged to Ascomycota and Chytridiomycota, and the dominance of Rozellomycota over Basidiomycota and Aphelidiomycota was observed. The majority of sediment fungal members were ascribed to unclassified fungi, with higher proportions in fish ponds than crab and crayfish ponds. Further, the fungal communities were markedly distinct among the three types of ponds, suggesting divergent patterns of fungal community assemblages caused by farming practices in aquaculture ponds. The community diversity and structure were closely correlated to sediment properties, especially sediment carbon content and pH. Thus, the distribution and pattern of fungal communities in the sediments appear to primarily depend on species-based farming practices responsible for the resulting sediment carbon content and pH in aquaculture ponds. This study provides a detailed snapshot and extension of understanding fungal community structure and variability in pond ecosystems, highlighting the impacts of farming practices on the assembly and succession of sediment fungal communities in aquaculture ponds.
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Affiliation(s)
- Zhimin Zhang
- Key Laboratory of Algal Biology, State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Qinghui Deng
- Key Laboratory of Algal Biology, State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xiuyun Cao
- Key Laboratory of Algal Biology, State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Yiyong Zhou
- Key Laboratory of Algal Biology, State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Chunlei Song
- Key Laboratory of Algal Biology, State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
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24
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Priest T, Fuchs B, Amann R, Reich M. Diversity and biomass dynamics of unicellular marine fungi during a spring phytoplankton bloom. Environ Microbiol 2020; 23:448-463. [PMID: 33201558 DOI: 10.1111/1462-2920.15331] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 11/11/2020] [Accepted: 11/12/2020] [Indexed: 12/01/2022]
Abstract
Microbial communities have important functions during spring phytoplankton blooms, regulating bloom dynamics and processing organic matter. Despite extensive research into such processes, an in-depth assessment of the fungal component is missing, especially for the smaller size fractions. We investigated the dynamics of unicellular mycoplankton during a spring phytoplankton bloom in the North Sea by 18S rRNA gene tag sequencing and a modified CARD-FISH protocol. Visualization and enumeration of dominant taxa revealed unique cell count patterns that varied considerably over short time scales. The Rozellomycota sensu lato (s.l.) reached a maximum of 105 cells L-1 , being comparable to freshwater counts. The abundance of Dikarya surpassed previous values by two orders of magnitude (105 cells L-1 ) and the corresponding biomass (maximum of 8.9 mg C m-3 ) was comparable to one reported for filamentous fungi with assigned ecological importance. Our results show that unicellular fungi are an abundant and, based on high cellular ribosome content and fast dynamics, active part of coastal microbial communities. The known ecology of the visualized taxa and the observed dynamics suggest the existence of different ecological niches that link primary and secondary food chains, highlighting the importance of unicellular fungi in food web structures and carbon transfer.
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Affiliation(s)
- Taylor Priest
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Bernhard Fuchs
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Rudolf Amann
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Marlis Reich
- Molecular Ecology Group, FB2, University of Bremen, Bremen, Germany
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25
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Roberts C, Allen R, Bird KE, Cunliffe M. Chytrid fungi shape bacterial communities on model particulate organic matter. Biol Lett 2020; 16:20200368. [PMID: 32991826 PMCID: PMC7532721 DOI: 10.1098/rsbl.2020.0368] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Microbial colonization and degradation of particulate organic matter (POM) are important processes that influence the structure and function of aquatic ecosystems. Although POM is readily used by aquatic fungi and bacteria, there is a limited understanding of POM-associated interactions between these taxa, particularly for early-diverging fungal lineages. Using a model ecological system with the chitin-degrading freshwater chytrid fungus Rhizoclosmatium globosum and chitin microbeads, we assessed the impacts of chytrid fungi on POM-associated bacteria. We show that the presence of chytrids on POM alters concomitant bacterial community diversity and structure, including differing responses between chytrid life stages. We propose that chytrids can act as ecosystem facilitators through saprotrophic feeding by producing ‘public goods’ from POM degradation that modify bacterial POM communities. This study suggests that chytrid fungi have complex ecological roles in aquatic POM degradation not previously considered, including the regulation of bacterial colonization, community succession and subsequent biogeochemical potential.
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Affiliation(s)
- Cordelia Roberts
- Marine Biological Association of the UK, The Laboratory, Citadel Hill, Plymouth, UK.,School of Biological and Marine Sciences, University of Plymouth, Plymouth, UK
| | - Ro Allen
- Marine Biological Association of the UK, The Laboratory, Citadel Hill, Plymouth, UK
| | - Kimberley E Bird
- Marine Biological Association of the UK, The Laboratory, Citadel Hill, Plymouth, UK
| | - Michael Cunliffe
- Marine Biological Association of the UK, The Laboratory, Citadel Hill, Plymouth, UK.,School of Biological and Marine Sciences, University of Plymouth, Plymouth, UK
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26
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Quemener M, Mara P, Schubotz F, Beaudoin D, Li W, Pachiadaki M, Sehein TR, Sylvan JB, Li J, Barbier G, Edgcomb V, Burgaud G. Meta-omics highlights the diversity, activity and adaptations of fungi in deep oceanic crust. Environ Microbiol 2020; 22:3950-3967. [PMID: 32743889 DOI: 10.1111/1462-2920.15181] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 07/23/2020] [Accepted: 07/31/2020] [Indexed: 02/03/2023]
Abstract
The lithified oceanic crust, lower crust gabbros in particular, has remained largely unexplored by microbiologists. Recently, evidence for heterogeneously distributed viable and transcriptionally active autotrophic and heterotrophic microbial populations within low-biomass communities was found down to 750 m below the seafloor at the Atlantis Bank Gabbro Massif, Indian Ocean. Here, we report on the diversity, activity and adaptations of fungal communities in the deep oceanic crust from ~10 to 780 mbsf by combining metabarcoding analyses with mid/high-throughput culturing approaches. Metabarcoding along with culturing indicate a low diversity of viable fungi, mostly affiliated to ubiquitous (terrestrial and aquatic environments) taxa. Ecophysiological analyses coupled with metatranscriptomics point to viable and transcriptionally active fungal populations engaged in cell division, translation, protein modifications and other vital cellular processes. Transcript data suggest possible adaptations for surviving in the nutrient-poor, lithified deep biosphere that include the recycling of organic matter. These active communities appear strongly influenced by the presence of cracks and veins in the rocks where fluids and resulting rock alteration create micro-niches.
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Affiliation(s)
- Maxence Quemener
- Université de Brest, EA 3882 Laboratoire Universitaire de Biodiversité et Ecologie Microbienne, Technopôle Brest-Iroise, Plouzané, France
| | - Paraskevi Mara
- Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA.,Department of Biology, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA
| | - Florence Schubotz
- MARUM-Center for Marine Environmental Sciences, University Bremen, Leobener Strasse 8, Bremen, 28359, Germany
| | - David Beaudoin
- Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA.,Department of Biology, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA
| | - Wei Li
- College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Maria Pachiadaki
- Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA.,Department of Biology, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA
| | - Taylor R Sehein
- Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA.,Department of Biology, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA
| | - Jason B Sylvan
- Department of Oceanography, Texas A&M University, College Station, TX, 77845, USA
| | - Jiangtao Li
- State Key Laboratory of Marine Geology, Tongji University, Shanghai, 200092, China
| | - Georges Barbier
- Université de Brest, EA 3882 Laboratoire Universitaire de Biodiversité et Ecologie Microbienne, Technopôle Brest-Iroise, Plouzané, France
| | - Virginia Edgcomb
- Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA.,Department of Biology, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543, USA
| | - Gaëtan Burgaud
- Université de Brest, EA 3882 Laboratoire Universitaire de Biodiversité et Ecologie Microbienne, Technopôle Brest-Iroise, Plouzané, France
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27
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Banos S, Gysi DM, Richter-Heitmann T, Glöckner FO, Boersma M, Wiltshire KH, Gerdts G, Wichels A, Reich M. Seasonal Dynamics of Pelagic Mycoplanktonic Communities: Interplay of Taxon Abundance, Temporal Occurrence, and Biotic Interactions. Front Microbiol 2020; 11:1305. [PMID: 32676057 PMCID: PMC7333250 DOI: 10.3389/fmicb.2020.01305] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 05/22/2020] [Indexed: 12/14/2022] Open
Abstract
Marine fungi are an important component of pelagic planktonic communities. However, it is not yet clear how individual fungal taxa are integrated in marine processes of the microbial loop and food webs. Most likely, biotic interactions play a major role in shaping the fungal community structure. Thus, the aim of our work was to identify possible biotic interactions of mycoplankton with phytoplankton and zooplankton groups and among fungi, and to investigate whether there is coherence between interactions and the dynamics, abundance and temporal occurrence of individual fungal OTUs. Marine surface water was sampled weekly over the course of 1 year, in the vicinity of the island of Helgoland in the German Bight (North Sea). The mycoplankton community was analyzed using 18S rRNA gene tag-sequencing and the identified dynamics were correlated to environmental data including phytoplankton, zooplankton, and abiotic factors. Finally, co-occurrence patterns of fungal taxa were detected with network analyses based on weighted topological overlaps (wTO). Of all abundant and persistent OTUs, 77% showed no biotic relations suggesting a saprotrophic lifestyle. Of all other fungal OTUs, nearly the half (44%) had at least one significant negative relationship, especially with zooplankton and other fungi, or to a lesser extent with phytoplankton. These findings suggest that mycoplankton OTUs are embedded into marine food web chains via highly complex and manifold relationships such as parasitism, predation, grazing, or allelopathy. Furthermore, about one third of all rare OTUs were part of a dense fungal co-occurrence network probably stabilizing the fungal community against environmental changes and acting as functional guilds or being involved in fungal cross-feeding. Placed in an ecological context, strong antagonistic relationships of the mycoplankton community with other components of the plankton suggest that: (i) there is a top-down control by fungi on zooplankton and phytoplankton; (ii) fungi serve as a food source for zooplankton and thereby transfer nutrients and organic material; (iii) the dynamics of fungi harmful to other plankton groups are controlled by antagonistic fungal taxa.
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Affiliation(s)
- Stefanos Banos
- Molecular Ecology Group, University of Bremen, Bremen, Germany
| | - Deisy Morselli Gysi
- Department of Computer Science, Interdisciplinary Center of Bioinformatics, University of Leipzig, Leipzig, Germany.,Swarm Intelligence and Complex Systems Group, Faculty of Mathematics and Computer Science, University of Leipzig, Leipzig, Germany.,Center for Complex Networks Research, Northeastern University, Boston, MA, United States
| | | | - Frank Oliver Glöckner
- Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, Germany.,Department of Life Sciences and Chemistry, Jacobs University Bremen gGmbH, Bremen, Germany.,MARUM, Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Maarten Boersma
- Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Biologische Anstalt Helgoland, Helgoland, Germany.,FB2, University of Bremen, Bremen, Germany
| | - Karen H Wiltshire
- Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Biologische Anstalt Helgoland, Helgoland, Germany.,Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Wattenmeerstation, List, Germany
| | - Gunnar Gerdts
- Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Biologische Anstalt Helgoland, Helgoland, Germany
| | - Antje Wichels
- Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Biologische Anstalt Helgoland, Helgoland, Germany
| | - Marlis Reich
- Molecular Ecology Group, University of Bremen, Bremen, Germany
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28
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Chrismas N, Cunliffe M. Depth-dependent mycoplankton glycoside hydrolase gene activity in the open ocean-evidence from the Tara Oceans eukaryote metatranscriptomes. ISME JOURNAL 2020; 14:2361-2365. [PMID: 32494052 PMCID: PMC7608184 DOI: 10.1038/s41396-020-0687-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 05/20/2020] [Accepted: 05/21/2020] [Indexed: 11/09/2022]
Abstract
Mycoplankton are widespread components of marine ecosystems, yet the full extent of their functional role remains poorly known. Marine mycoplankton are likely functionally analogous to their terrestrial counterparts, including performing saprotrophy and degrading high-molecular weight organic substrates using carbohydrate-active enzymes (CAZymes). We investigated the prevalence of transcribed oceanic fungal CAZyme genes using the Marine Atlas of Tara Ocean Unigenes database. We revealed an abundance of unique transcribed fungal glycoside hydrolases in the open ocean, including a particularly high number that act upon cellulose in surface waters and the deep chlorophyll maximum (DCM). A variety of other glycoside hydrolases acting on a range of biogeochemically important polysaccharides including β-glucans and chitin were also found. This analysis demonstrates that mycoplankton are active saprotrophs in the open ocean and paves the way for future research into the depth-dependent roles of marine fungi in oceanic carbon cycling, including the biological carbon pump.
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Affiliation(s)
- Nathan Chrismas
- Marine Biological Association of the UK, The Laboratory, Citadel Hill, Plymouth, UK. .,School of Geographical Sciences, University of Bristol, University Road, Bristol, UK.
| | - Michael Cunliffe
- Marine Biological Association of the UK, The Laboratory, Citadel Hill, Plymouth, UK. .,School of Biological and Marine Sciences, University of Plymouth, Plymouth, UK.
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29
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Highlighting the Crude Oil Bioremediation Potential of Marine Fungi Isolated from the Port of Oran (Algeria). DIVERSITY 2020. [DOI: 10.3390/d12050196] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
While over hundreds of terrestrial fungal genera have been shown to play important roles in the biodegradation of hydrocarbons, few studies have so far focused on the fungal bioremediation potential of petroleum in the marine environment. In this study, the culturable fungal communities occurring in the port of Oran in Algeria, considered here as a chronically-contaminated site, have been mainly analyzed in terms of species richness. A collection of 84 filamentous fungi has been established from seawater samples and then the fungi were screened for their ability to utilize and degrade crude oil. A total of 12 isolates were able to utilize crude oil as a unique carbon source, from which 4 were defined as the most promising biodegrading isolates based on a screening test using 2,6-dichlorophenol indophenol as a proxy to highlight their ability to metabolize crude oil. The biosurfactant production capability was also tested and, interestingly, the oil spreading and drop-collapse tests highlighted that the 4 most promising isolates were also those able to produce the highest quantity of biosurfactants. The results generated in this study demonstrate that the most promising fungal isolates, namely Penicillium polonicum AMF16, P. chrysogenum AMF47 and 2 isolates (AMF40 and AMF74) affiliated to P. cyclopium, appear to be interesting candidates for bioremediation of crude oil pollution in the marine environment within the frame of bioaugmentation or biostimulation processes.
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30
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Lacerda ALDF, Proietti MC, Secchi ER, Taylor JD. Diverse groups of fungi are associated with plastics in the surface waters of the Western South Atlantic and the Antarctic Peninsula. Mol Ecol 2020; 29:1903-1918. [DOI: 10.1111/mec.15444] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 03/30/2020] [Accepted: 04/02/2020] [Indexed: 12/19/2022]
Affiliation(s)
- Ana L. d. F. Lacerda
- Instituto de Oceanografia Universidade Federal do Rio Grande-FURG Rio Grande Brazil
| | - Maíra C. Proietti
- Instituto de Oceanografia Universidade Federal do Rio Grande-FURG Rio Grande Brazil
| | - Eduardo R. Secchi
- Instituto de Oceanografia Universidade Federal do Rio Grande-FURG Rio Grande Brazil
| | - Joe D. Taylor
- School of Science, Engineering and Environment University of Salford Manchester UK
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31
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Abstract
Fungi are phylogenetically and functionally diverse ubiquitous components of almost all ecosystems on Earth, including aquatic environments stretching from high montane lakes down to the deep ocean. Aquatic ecosystems, however, remain frequently overlooked as fungal habitats, although fungi potentially hold important roles for organic matter cycling and food web dynamics. Recent methodological improvements have facilitated a greater appreciation of the importance of fungi in many aquatic systems, yet a conceptual framework is still missing. In this Review, we conceptualize the spatiotemporal dimensions, diversity, functions and organismic interactions of fungi in structuring aquatic food webs. We focus on currently unexplored fungal diversity, highlighting poorly understood ecosystems, including emerging artificial aquatic habitats.
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32
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Highly diverse fungal communities in carbon-rich aquifers of two contrasting lakes in Northeast Germany. FUNGAL ECOL 2019. [DOI: 10.1016/j.funeco.2019.04.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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33
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Wang Y, Sen K, He Y, Xie Y, Wang G. Impact of environmental gradients on the abundance and diversity of planktonic fungi across coastal habitats of contrasting trophic status. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 683:822-833. [PMID: 31154160 DOI: 10.1016/j.scitotenv.2019.05.204] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 05/14/2019] [Accepted: 05/14/2019] [Indexed: 06/09/2023]
Abstract
Fungal communities in the coastal waters have long been known to be dynamic with a significant role in organic matter cycling. However, the effects of environmental gradients on their community structures are poorly described. Here we studied three coastal sites off the South China Sea, namely Pearl River Estuary (PE), Shenzhen Bay (SB), and Daya Bay (DB) with contrasting trophic status and heterogenous local influences. Environmental analysis of these sites suggested higher nutrient and low salinity levels at PE and SB with wide variability compared to DB. Average molecular abundances (18S rRNA gene copy numbers) at sites PE (1.05 ± 0.27 × 107 copies L-1) and SB (1.2 ± 0.69 × 107 copies L-1) were similar and significantly higher (P < 0.05) than that at site DB (5.5 ± 9.5 × 105 copies L-1). Although planktonic fungi were molecularly abundant at the three sites, live fungal biomass based on ergosterol assay was detected only at some stations of PE and SB. Both molecular abundance and live biomass were significantly correlated with chemical oxygen demand, nutrients, and phytoplankton biomass, supporting their role in detritus turnover. The fungal communities were unprecedently diverse with the ubiquitous dominance of Dikarya and the occasional predominance of Glomeromycota, Mucoromycota, Mortierellomycota, and Chytridiomycota. A total of 24 classes, 46 orders, 71 families, 59 genera, and eight species were classified within the eight detected phyla, including the new finding of ascomycetous class Geoglossomycetes in coastal waters. Salinity and nitrate were the significant (r2 = 0.70, P < 0.05) factors that determined the β-diversity of fungal communities. Overall, this study suggests that although planktonic fungi are ubiquitous in coastal habitats, their molecular abundances and diversities (both α and β) are significantly determined by environmental gradients, particularly the salinity, COD and nitrate levels of coastal waters.
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Affiliation(s)
- Yaqiong Wang
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; School of Ecology, Environment and Resources, Qinghai University for Nationalities, Xining, Qinghai 810007, China
| | - Kalyani Sen
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Yaodong He
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Yunxuan Xie
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Guangyi Wang
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin 300072, China.
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34
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Pilgaard B, Wilkens C, Herbst FA, Vuillemin M, Rhein-Knudsen N, Meyer AS, Lange L. Proteomic enzyme analysis of the marine fungus Paradendryphiella salina reveals alginate lyase as a minimal adaptation strategy for brown algae degradation. Sci Rep 2019; 9:12338. [PMID: 31451726 PMCID: PMC6710412 DOI: 10.1038/s41598-019-48823-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 08/13/2019] [Indexed: 01/31/2023] Open
Abstract
We set out to investigate the genetic adaptations of the marine fungus Paradendryphiella salina CBS112865 for degradation of brown macroalgae. We performed whole genome and transcriptome sequencing and shotgun proteomic analysis of the secretome of P. salina grown on three species of brown algae and under carbon limitation. Genome comparison with closely related terrestrial fungi revealed that P. salina had a similar but reduced CAZyme profile relative to the terrestrial fungi except for the presence of three putative alginate lyases from Polysaccharide Lyase (PL) family 7 and a putative PL8 with similarity to ascomycete chondroitin AC lyases. Phylogenetic and homology analyses place the PL7 sequences amongst mannuronic acid specific PL7 proteins from marine bacteria. Recombinant expression, purification and characterization of one of the PL7 genes confirmed the specificity. Proteomic analysis of the P. salina secretome when growing on brown algae, revealed the PL7 and PL8 enzymes abundantly secreted together with enzymes necessary for degradation of laminarin, cellulose, lipids and peptides. Our findings indicate that the basic CAZyme repertoire of saprobic and plant pathogenic ascomycetes, with the addition of PL7 alginate lyases, provide P. salina with sufficient enzymatic capabilities to degrade several types of brown algae polysaccharides.
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Affiliation(s)
- Bo Pilgaard
- Enzyme Technology, Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark.
| | - Casper Wilkens
- Enzyme Technology, Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Florian-Alexander Herbst
- Center for Microbial Communities, Department of Chemistry and Bioscience Aalborg University, Aalborg, Denmark
| | - Marlene Vuillemin
- Enzyme Technology, Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Nanna Rhein-Knudsen
- Enzyme Technology, Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Anne S Meyer
- Enzyme Technology, Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Lene Lange
- BioEconomy, Research & Advisory, Copenhagen, Denmark
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35
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Amend A, Burgaud G, Cunliffe M, Edgcomb VP, Ettinger CL, Gutiérrez MH, Heitman J, Hom EFY, Ianiri G, Jones AC, Kagami M, Picard KT, Quandt CA, Raghukumar S, Riquelme M, Stajich J, Vargas-Muñiz J, Walker AK, Yarden O, Gladfelter AS. Fungi in the Marine Environment: Open Questions and Unsolved Problems. mBio 2019; 10:e01189-18. [PMID: 30837337 PMCID: PMC6401481 DOI: 10.1128/mbio.01189-18] [Citation(s) in RCA: 134] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Terrestrial fungi play critical roles in nutrient cycling and food webs and can shape macroorganism communities as parasites and mutualists. Although estimates for the number of fungal species on the planet range from 1.5 to over 5 million, likely fewer than 10% of fungi have been identified so far. To date, a relatively small percentage of described species are associated with marine environments, with ∼1,100 species retrieved exclusively from the marine environment. Nevertheless, fungi have been found in nearly every marine habitat explored, from the surface of the ocean to kilometers below ocean sediments. Fungi are hypothesized to contribute to phytoplankton population cycles and the biological carbon pump and are active in the chemistry of marine sediments. Many fungi have been identified as commensals or pathogens of marine animals (e.g., corals and sponges), plants, and algae. Despite their varied roles, remarkably little is known about the diversity of this major branch of eukaryotic life in marine ecosystems or their ecological functions. This perspective emerges from a Marine Fungi Workshop held in May 2018 at the Marine Biological Laboratory in Woods Hole, MA. We present the state of knowledge as well as the multitude of open questions regarding the diversity and function of fungi in the marine biosphere and geochemical cycles.
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Affiliation(s)
- Anthony Amend
- Department of Botany, University of Hawai'i at Manoa, Honolulu, Hawaii, USA
| | - Gaetan Burgaud
- Université de Brest, EA 3882, Laboratoire Universitaire de Biodiversité et Ecologie Microbienne, ESIAB, Technopôle Brest-Iroise, Plouzané, France
| | - Michael Cunliffe
- Marine Biological Association of the United Kingdom, The Laboratory, Citadel Hill, Plymouth, United Kingdom
| | - Virginia P Edgcomb
- Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts, USA
| | | | - M H Gutiérrez
- Departamento de Oceanografía, Centro de Investigación Oceanográfica COPAS Sur-Austral, Universidad de Concepción, Concepción, Chile
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, USA
| | - Erik F Y Hom
- Department of Biology, University of Mississippi, Oxford, Mississippi, USA
| | - Giuseppe Ianiri
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, USA
| | - Adam C Jones
- Gordon and Betty Moore Foundation, Palo Alto, California, USA
| | - Maiko Kagami
- Graduate School of Environment and Information Sciences, Yokohama National University, Yokohama, Japan
| | - Kathryn T Picard
- Department of Botany, National Museum of Natural History, Smithsonian Institution, Washington, DC, USA
| | - C Alisha Quandt
- Ecology and Evolutionary Biology Department, University of Colorado, Boulder, Colorado, USA
| | | | - Mertixell Riquelme
- Department of Microbiology, Centro de Investigación Científica y Educación Superior de Ensenada (CICESE), Ensenada, Baja California, Mexico
| | - Jason Stajich
- Department of Microbiology & Plant Pathology and Institute for Integrative Genome Biology, University of California-Riverside, Riverside, California, USA
| | - José Vargas-Muñiz
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Allison K Walker
- Department of Biology, Acadia University, Wolfville, Nova Scotia, Canada
| | - Oded Yarden
- Department of Plant Pathology and Microbiology, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Amy S Gladfelter
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Marine Biological Laboratory, Woods Hole, Massachusetts, USA
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36
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A High-Resolution Time Series Reveals Distinct Seasonal Patterns of Planktonic Fungi at a Temperate Coastal Ocean Site (Beaufort, North Carolina, USA). Appl Environ Microbiol 2018; 84:AEM.00967-18. [PMID: 30143506 DOI: 10.1128/aem.00967-18] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 08/17/2018] [Indexed: 11/20/2022] Open
Abstract
There is a growing awareness of the ecological and biogeochemical importance of fungi in coastal marine systems. While highly diverse fungi have been discovered in these marine systems, still, little is known about their seasonality and associated drivers in coastal waters. Here, we examined fungal communities over 3 years of weekly sampling at a dynamic, temperate coastal site (Pivers Island Coastal Observatory [PICO], Beaufort, NC, USA). Fungal 18S rRNA gene abundance, operational taxonomic unit (OTU) richness, and Shannon's diversity index values exhibited prominent seasonality. Fungal 18S rRNA gene copies peaked in abundance during the summer and fall, with positive correlations with chlorophyll a, SiO4, and oxygen saturation. Diversity (measured using internal transcribed spacer [ITS] libraries) was highest during winter and lowest during summer; it was linked to temperature, pH, chlorophyll a, insolation, salinity, and dissolved inorganic carbon (DIC). Fungal communities derived from ITS libraries were dominated throughout the year by Ascomycota, with contributions from Basidiomycota, Chytridiomycota, and Mucoromycotina, and their seasonal patterns linked to water temperature, light, and the carbonate system. Network analysis revealed that while cooccurrence and exclusion existed within fungus networks, exclusion dominated the fungus-and-phytoplankton network, in contrast with reported pathogenic and nutritional interactions between marine phytoplankton and fungi. Compared with the seasonality of bacterial communities in the same samples, the timing, extent, and associated environmental variables for fungi community are unique. These results highlight the fungal seasonal dynamics in coastal water and improve our understanding of the ecology of planktonic fungi.IMPORTANCE Coastal fungal dynamics were long assumed to be due to terrestrial inputs; here, a high-resolution time series reveals strong, repeating annual patterns linked to in situ environmental conditions, arguing for a resident coastal fungal community shaped by environmental factors. These seasonal patterns do, however, differ from those observed in the bacterioplankton at the same site; e.g., fungal diversity peaks in winter, whereas bacterial diversity maxima occur in the spring and fall. While the dynamics of these communities are linked to water temperature and insolation, fungi are also influenced by the carbonate system (pH and DIC). As both fungi and heterotrophic bacteria are thought to be key organic-material metabolizers, differences in their environmental drivers may offer clues as to which group dominates secondary production at this dynamic site. Overall, this study suggests the unique ecological roles of mycoplankton and their potentially broad niche complementarities to other microbial groups in the coastal ocean.
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