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Wang S, Tang W, Delage E, Gifford S, Whitby H, González AG, Eveillard D, Planquette H, Cassar N. Investigating the microbial ecology of coastal hotspots of marine nitrogen fixation in the western North Atlantic. Sci Rep 2021; 11:5508. [PMID: 33750865 PMCID: PMC7943828 DOI: 10.1038/s41598-021-84969-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 01/27/2021] [Indexed: 11/24/2022] Open
Abstract
Variation in the microbial cycling of nutrients and carbon in the ocean is an emergent property of complex planktonic communities. While recent findings have considerably expanded our understanding of the diversity and distribution of nitrogen (N2) fixing marine diazotrophs, knowledge gaps remain regarding ecological interactions between diazotrophs and other community members. Using quantitative 16S and 18S V4 rDNA amplicon sequencing, we surveyed eukaryotic and prokaryotic microbial communities from samples collected in August 2016 and 2017 across the Western North Atlantic. Leveraging and significantly expanding an earlier published 2015 molecular dataset, we examined microbial community structure and ecological co-occurrence relationships associated with intense hotspots of N2 fixation previously reported at sites off the Southern New England Shelf and Mid-Atlantic Bight. Overall, we observed a negative relationship between eukaryotic diversity and both N2 fixation and net community production (NCP). Maximum N2 fixation rates occurred at sites with high abundances of mixotrophic stramenopiles, notably Chrysophyceae. Network analysis revealed such stramenopiles to be keystone taxa alongside the haptophyte diazotroph host Braarudosphaera bigelowii and chlorophytes. Our findings highlight an intriguing relationship between marine stramenopiles and high N2 fixation coastal sites.
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Affiliation(s)
- Seaver Wang
- Division of Earth and Ocean Sciences, Duke University, Grainger Environment Hall, 9 Circuit Drive, Box 90328, Durham, NC, 27708, USA
| | - Weiyi Tang
- Department of Geosciences, Princeton University, Princeton, NJ, USA
| | - Erwan Delage
- LS2N, UMR 6004, CNRS, Université de Nantes, 44000, Nantes, France
| | - Scott Gifford
- Department of Marine Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Hannah Whitby
- Department of Earth, Ocean, and Ecological Sciences, School of Environmental Sciences, University of Liverpool, Liverpool, UK
| | - Aridane G González
- Instituto de Oceanografía y Cambio Global (IOCAG), Universidad de Las Palmas de Gran Canaria, ULPGC, Las Palmas, Spain.,Laboratoire des Sciences de l'Environnement Marin (LEMAR), Institut Universitaire Européen de la Mer (IUEM), Technopôle Brest-Iroise, 13 Plouzané, 29280, Locmaria-Plouzané, France
| | - Damien Eveillard
- LS2N, UMR 6004, CNRS, Université de Nantes, 44000, Nantes, France
| | - Hélène Planquette
- Laboratoire des Sciences de l'Environnement Marin (LEMAR), Institut Universitaire Européen de la Mer (IUEM), Technopôle Brest-Iroise, 13 Plouzané, 29280, Locmaria-Plouzané, France
| | - Nicolas Cassar
- Division of Earth and Ocean Sciences, Duke University, Grainger Environment Hall, 9 Circuit Drive, Box 90328, Durham, NC, 27708, USA. .,Laboratoire des Sciences de l'Environnement Marin (LEMAR), Institut Universitaire Européen de la Mer (IUEM), Technopôle Brest-Iroise, 13 Plouzané, 29280, Locmaria-Plouzané, France.
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52
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Lind AL, Pollard KS. Accurate and sensitive detection of microbial eukaryotes from whole metagenome shotgun sequencing. MICROBIOME 2021; 9:58. [PMID: 33658077 PMCID: PMC7931531 DOI: 10.1186/s40168-021-01015-y] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Accepted: 02/02/2021] [Indexed: 05/08/2023]
Abstract
BACKGROUND Microbial eukaryotes are found alongside bacteria and archaea in natural microbial systems, including host-associated microbiomes. While microbial eukaryotes are critical to these communities, they are challenging to study with shotgun sequencing techniques and are therefore often excluded. RESULTS Here, we present EukDetect, a bioinformatics method to identify eukaryotes in shotgun metagenomic sequencing data. Our approach uses a database of 521,824 universal marker genes from 241 conserved gene families, which we curated from 3713 fungal, protist, non-vertebrate metazoan, and non-streptophyte archaeplastida genomes and transcriptomes. EukDetect has a broad taxonomic coverage of microbial eukaryotes, performs well on low-abundance and closely related species, and is resilient against bacterial contamination in eukaryotic genomes. Using EukDetect, we describe the spatial distribution of eukaryotes along the human gastrointestinal tract, showing that fungi and protists are present in the lumen and mucosa throughout the large intestine. We discover that there is a succession of eukaryotes that colonize the human gut during the first years of life, mirroring patterns of developmental succession observed in gut bacteria. By comparing DNA and RNA sequencing of paired samples from human stool, we find that many eukaryotes continue active transcription after passage through the gut, though some do not, suggesting they are dormant or nonviable. We analyze metagenomic data from the Baltic Sea and find that eukaryotes differ across locations and salinity gradients. Finally, we observe eukaryotes in Arabidopsis leaf samples, many of which are not identifiable from public protein databases. CONCLUSIONS EukDetect provides an automated and reliable way to characterize eukaryotes in shotgun sequencing datasets from diverse microbiomes. We demonstrate that it enables discoveries that would be missed or clouded by false positives with standard shotgun sequence analysis. EukDetect will greatly advance our understanding of how microbial eukaryotes contribute to microbiomes. Video abstract.
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Affiliation(s)
- Abigail L Lind
- Gladstone Institute of Data Science and Biotechnology, San Francisco, CA, USA
| | - Katherine S Pollard
- Gladstone Institute of Data Science and Biotechnology, San Francisco, CA, USA.
- Institute for Human Genetics, University of California, San Francisco, CA, USA.
- Department of Epidemiology and Biostatistics, University of California, San Francisco, CA, USA.
- Institute for Computational Health Sciences, University of California, San Francisco, CA, USA.
- Chan Zuckerberg Biohub, San Francisco, CA, USA.
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53
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A metatranscriptomic analysis of changing dynamics in the plankton communities adjacent to aquaculture leases in southern Tasmania, Australia. Mar Genomics 2021; 59:100858. [PMID: 33642199 DOI: 10.1016/j.margen.2021.100858] [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: 08/24/2020] [Revised: 02/08/2021] [Accepted: 02/14/2021] [Indexed: 10/22/2022]
Abstract
Aquaculture releases nitrogen to the marine environment, potentially changing dynamics of local plankton populations and causing adverse impacts. Metatranscriptomics have been used to study planktonic nutrient cycles and community dynamics. We hypothesised that the metatranscriptome could be used to monitor changing phytoplankton physiology near leases. To test this hypothesis, opportunistic samples were collected from one oceanic location in winter and one estuarine location in spring and analysed via RNASeq. Transcriptomes from different locations were found to have little overlap, due to different community compositions in the oceanic and estuarine locations. Transcript function was similar at each location. Proximity to the salmon pen had little influence over the transcriptome at the estuarine location. In the oceanic environment, diatom-based activity decreased near pens and dinoflagellate-based activity increased as demonstrated through the abundance of carbon fixation and nitrogen-acquisition-related transcripts. Our initial results suggest that the use of the metatranscriptome in monitoring is promising.
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54
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Turnšek J, Brunson JK, Viedma MDPM, Deerinck TJ, Horák A, Oborník M, Bielinski VA, Allen AE. Proximity proteomics in a marine diatom reveals a putative cell surface-to-chloroplast iron trafficking pathway. eLife 2021; 10:e52770. [PMID: 33591270 PMCID: PMC7972479 DOI: 10.7554/elife.52770] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 02/15/2021] [Indexed: 12/16/2022] Open
Abstract
Iron is a biochemically critical metal cofactor in enzymes involved in photosynthesis, cellular respiration, nitrate assimilation, nitrogen fixation, and reactive oxygen species defense. Marine microeukaryotes have evolved a phytotransferrin-based iron uptake system to cope with iron scarcity, a major factor limiting primary productivity in the global ocean. Diatom phytotransferrin is endocytosed; however, proteins downstream of this environmentally ubiquitous iron receptor are unknown. We applied engineered ascorbate peroxidase APEX2-based subcellular proteomics to catalog proximal proteins of phytotransferrin in the model marine diatom Phaeodactylum tricornutum. Proteins encoded by poorly characterized iron-sensitive genes were identified including three that are expressed from a chromosomal gene cluster. Two of them showed unambiguous colocalization with phytotransferrin adjacent to the chloroplast. Further phylogenetic, domain, and biochemical analyses suggest their involvement in intracellular iron processing. Proximity proteomics holds enormous potential to glean new insights into iron acquisition pathways and beyond in these evolutionarily, ecologically, and biotechnologically important microalgae.
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Affiliation(s)
- Jernej Turnšek
- Biological and Biomedical Sciences, The Graduate School of Arts and Sciences, Harvard UniversityCambridgeUnited States
- Department of Systems Biology, Harvard Medical SchoolBostonUnited States
- Wyss Institute for Biologically Inspired Engineering, Harvard UniversityBostonUnited States
- Integrative Oceanography Division, Scripps Institution of Oceanography, University of California San DiegoLa JollaUnited States
- Center for Research in Biological Systems, University of California San DiegoLa JollaUnited States
- Microbial and Environmental Genomics, J. Craig Venter InstituteLa JollaUnited States
| | - John K Brunson
- Microbial and Environmental Genomics, J. Craig Venter InstituteLa JollaUnited States
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San DiegoLa JollaUnited States
| | | | - Thomas J Deerinck
- National Center for Microscopy and Imaging Research, University of California San DiegoLa JollaUnited States
| | - Aleš Horák
- Biology Centre CAS, Institute of ParasitologyČeské BudějoviceCzech Republic
- University of South Bohemia, Faculty of ScienceČeské BudějoviceCzech Republic
| | - Miroslav Oborník
- Biology Centre CAS, Institute of ParasitologyČeské BudějoviceCzech Republic
- University of South Bohemia, Faculty of ScienceČeské BudějoviceCzech Republic
| | - Vincent A Bielinski
- Synthetic Biology and Bioenergy, J. Craig Venter InstituteLa JollaUnited States
| | - Andrew Ellis Allen
- Integrative Oceanography Division, Scripps Institution of Oceanography, University of California San DiegoLa JollaUnited States
- Microbial and Environmental Genomics, J. Craig Venter InstituteLa JollaUnited States
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Li R, Hu C, Wang J, Sun J, Wang Y, Jiao N, Xu D. Biogeographical Distribution and Community Assembly of Active Protistan Assemblages Along an Estuary to a Basin Transect of the Northern South China Sea. Microorganisms 2021; 9:microorganisms9020351. [PMID: 33578968 PMCID: PMC7916720 DOI: 10.3390/microorganisms9020351] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 01/28/2021] [Accepted: 02/05/2021] [Indexed: 11/21/2022] Open
Abstract
Marine protists are essential for globally critical biological processes, including the biogeochemical cycles of matter and energy. However, compared with their prokaryotic counterpart, it remains largely unclear how environmental factors determine the diversity and distribution of the active protistan communities on the regional scale. In the present study, the biodiversity, community composition, and potential drivers of the total, abundant, and rare protistan groups were studied using high throughput sequencing on the V9 hyper-variable regions of the small subunit ribosomal RNA (SSU rRNA) along an estuary to basin transect in the northern South China Sea. Overall, Bacillariophyta and Cercozoa were abundant in the surface water; heterotrophic protists including Spirotrichea and marine stramenopiles 3 (MAST-3) were more abundant in the subsurface waters near the heavily urbanized Pearl River estuary; Chlorophyta and Pelagophyceae were abundant at the deep chlorophyll maximum depth, while Hacrobia, Radiolaria, and Excavata were the abundant groups in the deep water. Salinity, followed by water depth, temperature, and other biological factors, were the primary factors controlling the distinct vertical and horizontal distribution of the total and abundant protists. Rare taxa were driven by water depth, followed by temperature, salinity, and the concentrations of PO43−. The active protistan communities were mainly driven by dispersal limitation, followed by drift and other ecological processes.
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Affiliation(s)
- Ran Li
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China; (R.L.); (C.H.); (J.W.); (Y.W.)
- Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen 361102, China
| | - Chen Hu
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China; (R.L.); (C.H.); (J.W.); (Y.W.)
- Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen 361102, China
| | - Jianning Wang
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China; (R.L.); (C.H.); (J.W.); (Y.W.)
- Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen 361102, China
| | - Jun Sun
- College of Marine Science and Technology, China University of Geosciences (Wuhan), Wuhan 430000, China;
| | - Ying Wang
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China; (R.L.); (C.H.); (J.W.); (Y.W.)
- Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen 361102, China
| | - Nianzhi Jiao
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China; (R.L.); (C.H.); (J.W.); (Y.W.)
- Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen 361102, China
- Correspondence: (N.J.); (D.X.)
| | - Dapeng Xu
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China; (R.L.); (C.H.); (J.W.); (Y.W.)
- Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen 361102, China
- Correspondence: (N.J.); (D.X.)
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Sibbald SJ, Lawton M, Archibald JM. Mitochondrial Genome Evolution in Pelagophyte Algae. Genome Biol Evol 2021; 13:6126422. [PMID: 33675661 PMCID: PMC7936722 DOI: 10.1093/gbe/evab018] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/27/2021] [Indexed: 11/19/2022] Open
Abstract
The Pelagophyceae are marine stramenopile algae that include Aureoumbra lagunensis and Aureococcus anophagefferens, two microbial species notorious for causing harmful algal blooms. Despite their ecological significance, relatively few genomic studies of pelagophytes have been carried out. To improve understanding of the biology and evolution of pelagophyte algae, we sequenced complete mitochondrial genomes for A. lagunensis (CCMP1510), Pelagomonas calceolata (CCMP1756), and five strains of Aureoc. anophagefferens (CCMP1707, CCMP1708, CCMP1850, CCMP1984, and CCMP3368) using Nanopore long-read sequencing. All pelagophyte mitochondrial genomes assembled into single, circular mapping contigs between 39,376 bp (P. calceolata) and 55,968 bp (A. lagunensis) in size. Mitochondrial genomes for the five Aureoc. anophagefferens strains varied slightly in length (42,401–42,621 bp) and were 99.4–100.0% identical. Gene content and order were highly conserved between the Aureoc. anophagefferens and P. calceolata genomes, with the only major difference being a unique region in Aureoc. anophagefferens containingDNA adenine and cytosine methyltransferase (dam/dcm) genes that appear to be the product of lateral gene transfer from a prokaryotic or viral donor. Although the A. lagunensis mitochondrial genome shares seven distinct syntenic blocks with the other pelagophyte genomes, it has a tandem repeat expansion comprising ∼40% of its length, and lacks identifiable rps19 and glycine tRNA genes. Laterally acquired self-splicing introns were also found in the 23S rRNA (rnl) gene of P. calceolata and the coxI gene of the five Aureoc. anophagefferens genomes. Overall, these data provide baseline knowledge about the genetic diversity of bloom-forming pelagophytes relative to nonbloom-forming species.
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Affiliation(s)
- Shannon J Sibbald
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada.,Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Maggie Lawton
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada.,Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - John M Archibald
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada.,Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
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Bellas CM, Sommaruga R. Polinton-like viruses are abundant in aquatic ecosystems. MICROBIOME 2021; 9:13. [PMID: 33436089 PMCID: PMC7805220 DOI: 10.1186/s40168-020-00956-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 12/06/2020] [Indexed: 05/28/2023]
Abstract
BACKGROUND Polintons are large mobile genetic elements found in the genomes of eukaryotic organisms that are considered the ancient ancestors of most eukaryotic dsDNA viruses. Originally considered as transposons, they have been found to encode virus capsid genes, suggesting they may actually be integrated viruses; however, an extracellular form has yet to be detected. Recently, circa 25 Polinton-like viruses have been discovered in environmental metagenomes and algal genomes, which shared distantly related genes to both Polintons and virophages (Lavidaviridae). These entities could be the first members of a major class of ancient eukaryotic viruses; however, owing to the lack of available genomes for analysis, information on their global diversity, evolutionary relationships, eukaryotic hosts, and status as free virus particles is limited. RESULTS Here, we analysed the metaviromes of an alpine lake to show that Polinton-like virus genome sequences are abundant in the water column. We identify major capsid protein genes belonging to 82 new Polinton-like viruses and use these to interrogate publicly available metagenomic datasets, identifying 543 genomes and a further 16 integrated into eukaryotic genomes. Using an analysis of shared gene content and major capsid protein phylogeny, we define large groups of Polinton-like viruses and link them to diverse eukaryotic hosts, including a new group of viruses, which possess all the core genes of virophages and infect oomycetes and Chrysophyceae. CONCLUSIONS Our study increased the number of known Polinton-like viruses by 25-fold, identifying five major new groups of eukaryotic viruses, which until now have been hidden in metagenomic datasets. The large enrichment (> 100-fold) of Polinton-like virus sequences in the virus-sized fraction of this alpine lake and the fact that their viral major capsid proteins are found in eukaryotic host transcriptomes support the hypothesis that Polintons in unicellular eukaryotes are viruses. In summary, our data reveals a diverse assemblage of globally distributed viruses, associated with a wide range of unicellular eukaryotic hosts. We anticipate that the methods we have developed for Polinton-like virus detection and the database of over 20,000 genes we present will allow for continued discovery and analysis of these new viral groups. Video abstract.
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Affiliation(s)
- Christopher M. Bellas
- Department of Ecology, University of Innsbruck, Technikerstrasse 25, A-6020 Innsbruck, Austria
| | - Ruben Sommaruga
- Department of Ecology, University of Innsbruck, Technikerstrasse 25, A-6020 Innsbruck, Austria
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58
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Gu R, Sun P, Wang Y, Yu F, Jiao N, Xu D. Genetic Diversity, Community Assembly, and Shaping Factors of Benthic Microbial Eukaryotes in Dongshan Bay, Southeast China. Front Microbiol 2020; 11:592489. [PMID: 33424795 PMCID: PMC7785585 DOI: 10.3389/fmicb.2020.592489] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 11/27/2020] [Indexed: 11/28/2022] Open
Abstract
Microbial eukaryotes are pivotal components of marine ecosystems. However, compared with the pelagic environments, the diversity distribution and the driving mechanisms of microbial eukaryotes in the marine sediments have rarely been explored. In this study, sediment cores were collected along a transect from inner to outer Dongshan Bay, Southeast China. By combining high throughput sequencing of small-subunit (SSU) rRNA gene with measurements on multiple environmental variables, the genetic diversity, community structure and assembly processes, and environmental shaping factors were investigated. Alveolata (mainly Ciliophora and Dinophyceae), Rhizaria (mainly Cercozoa), and Stramenopiles (mainly Bacillariophyta) were the most dominant groups in terms of both relative sequence abundance and operational taxonomic unit (OTU) richness. Grain size composition of the sediment was the primary factor determining the alpha diversity of microbial eukaryotes followed by sediment depth and heavy metal, including chromium (Cr), zinc (Zn), and plumbum (Pb). Geographic distance and water depth surpassed other environmental factors to be the primary factors shaping the microbial eukaryotic communities. Dispersal limitation was the primary driver of the microbial eukaryotic communities, followed by drift and homogeneous selection. Overall, our study shed new light on the spatial distribution patterns and controlling factors of benthic microbial eukaryotes in a subtropical bay which is subjected to increasing anthropogenic pressure.
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Affiliation(s)
- Rong Gu
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, China
- College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
- Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen, China
| | - Ping Sun
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, College of the Environment and Ecology, Xiamen University, Xiamen, China
- Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies, Xiamen University, Xiamen, China
| | - Ying Wang
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, China
- College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
- Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen, China
| | - Fengling Yu
- College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Nianzhi Jiao
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, China
- College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
- Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen, China
| | - Dapeng Xu
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, China
- College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
- Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen, China
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Zhu W, Qin C, Ma H, Xi S, Zuo T, Pan W, Li C. Response of protist community dynamics and co-occurrence patterns to the construction of artificial reefs: A case study in Daya Bay, China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 742:140575. [PMID: 32623178 DOI: 10.1016/j.scitotenv.2020.140575] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 06/16/2020] [Accepted: 06/26/2020] [Indexed: 05/25/2023]
Abstract
Artificial reefs (ARs) are widely used for biodiversity conservation and coastal habitat restoration. Although protists play an important ecological role in marine ecosystems, the response of the protist community to ARs is still poorly understood. In the current study, an Illumina sequencing analysis of 18S rDNA was performed, and the diversity, community structure, and co-occurrence networks of protists in the ARs and open sea area (OW) in Daya Bay were described. The results indicated that significant seasonal differences occur in the seawater protists between the surface and bottom of the ARs and OW. However, the protists in the ARs and OW had different seasonal variations. The ARs always affected the alpha diversity of marine protists in different seasons, while the surface and bottom OW sites had different seasonal effects. The ARs sites had different effects on the community composition of the surface and bottom seawater in different seasons relative to the OW sites. The linear discriminant analysis (LDA) effect size (LEfSe) method showed that 85 biomarkers mainly belonging to 11 taxa, including Bacillariophyta, Chlorophyta, and Dinophyceae, were affected by the ARs (P < 0.05, LDA > 2.0). The ARs played an important role in the seasonal changes in the protist community composition and had different effects on the dominant species of protists in the surface and bottom seawater. A redundancy analysis (RDA) significance test showed that the structure of the protist community in Daya Bay was mainly affected by environmental factors, such as seawater temperature, salinity and dissolved oxygen. Compared with the OW group, the surface and bottom layers of the ARs had more complex protist interactions or more niches. The ARs increased the degree of spatial heterogeneity, which may lead to significant niche differentiation, indicating that ARs as habitat factors affect the complexity and stability of the symbiotic network of protists. The results could provide basic data on the response of the protist community to the ARs in Daya Bay and a reference for assessments of the impact of ARs on the ecological environment.
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Affiliation(s)
- Wentao Zhu
- South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China; National Fishery Resources and Environment Dapeng Observation and Experimental Station, Shenzhen 518120, China; Scientific Observing and Experimental Station of South China Sea Fishery Resources & Environment, Ministry of Agriculture and Rural Affair, Guangzhou 510300, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou 511458, China; College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China
| | - Chuanxin Qin
- South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China; National Fishery Resources and Environment Dapeng Observation and Experimental Station, Shenzhen 518120, China; Guangdong Provincial Key Lab. of Fishery Ecology and Environment, Guangzhou 510300, China; Scientific Observing and Experimental Station of South China Sea Fishery Resources & Environment, Ministry of Agriculture and Rural Affair, Guangzhou 510300, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou 511458, China.
| | - Hongmei Ma
- South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China; National Fishery Resources and Environment Dapeng Observation and Experimental Station, Shenzhen 518120, China; Scientific Observing and Experimental Station of South China Sea Fishery Resources & Environment, Ministry of Agriculture and Rural Affair, Guangzhou 510300, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou 511458, China
| | - Shigai Xi
- South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China; National Fishery Resources and Environment Dapeng Observation and Experimental Station, Shenzhen 518120, China; Scientific Observing and Experimental Station of South China Sea Fishery Resources & Environment, Ministry of Agriculture and Rural Affair, Guangzhou 510300, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou 511458, China
| | - Tao Zuo
- South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China; National Fishery Resources and Environment Dapeng Observation and Experimental Station, Shenzhen 518120, China; Scientific Observing and Experimental Station of South China Sea Fishery Resources & Environment, Ministry of Agriculture and Rural Affair, Guangzhou 510300, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou 511458, China
| | - Wanni Pan
- South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China; National Fishery Resources and Environment Dapeng Observation and Experimental Station, Shenzhen 518120, China; Scientific Observing and Experimental Station of South China Sea Fishery Resources & Environment, Ministry of Agriculture and Rural Affair, Guangzhou 510300, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou 511458, China; College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China
| | - Chunhou Li
- South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300, China; National Fishery Resources and Environment Dapeng Observation and Experimental Station, Shenzhen 518120, China; Guangdong Provincial Key Lab. of Fishery Ecology and Environment, Guangzhou 510300, China; Scientific Observing and Experimental Station of South China Sea Fishery Resources & Environment, Ministry of Agriculture and Rural Affair, Guangzhou 510300, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou 511458, China
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Thangaraj S, Sun J. Transcriptomic reprogramming of the oceanic diatom Skeletonema dohrnii under warming ocean and acidification. Environ Microbiol 2020; 23:980-995. [PMID: 32975013 DOI: 10.1111/1462-2920.15248] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 09/14/2020] [Accepted: 09/20/2020] [Indexed: 12/19/2022]
Abstract
Under ocean warming and acidification, diatoms use a unique acclimation and adaptation strategy by saving energy and utilizing it for other cellular processes. However, the molecular mechanisms that underlie this reprogramming of energy utilization are currently unknown. Here, we investigate the metabolic reprogramming of the ecologically important diatom Skeletonema dohrnii grown under two different temperature (21°C and 25°C) and pCO2 (400 and 1000 ppm) levels, utilizing global transcriptomic analysis. We find that evolutionary changes in the baseline gene expression, which we termed transcriptional up- and downregulation, is the primary mechanism used by diatoms to acclimate to the combined conditions of ocean warming and acidification. This transcriptional regulation shows that under higher temperature and pCO2 conditions, photosynthesis, electron transport and carboxylation were modified with increasing abundances of genes encoding ATP, NADPH and carbon gaining for the carbon-dioxide-concentrating mechanisms (CCMs). Our results also indicate that changes in the transcriptional regulation of CCMs led to a decrease in the metabolic cost to save energy by promoting amino acid synthesis and nitrogen assimilation for the active protein processing machinery to adapt to warming and ocean acidification. This study generated unique metabolic insights into diatoms and suggests that future climate change conditions will cause evolutionary changes in oceanic diatoms that will facilitate their acclimation strategy.
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Affiliation(s)
- Satheeswaran Thangaraj
- College of Marine Science and Technology, China University of Geosciences (Wuhan), Wuhan, Hubei, 430074, China
| | - Jun Sun
- College of Marine Science and Technology, China University of Geosciences (Wuhan), Wuhan, Hubei, 430074, China
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61
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Massana R, Labarre A, López-Escardó D, Obiol A, Bucchini F, Hackl T, Fischer MG, Vandepoele K, Tikhonenkov DV, Husnik F, Keeling PJ. Gene expression during bacterivorous growth of a widespread marine heterotrophic flagellate. ISME JOURNAL 2020; 15:154-167. [PMID: 32920602 PMCID: PMC7852580 DOI: 10.1038/s41396-020-00770-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Revised: 08/19/2020] [Accepted: 09/02/2020] [Indexed: 11/17/2022]
Abstract
Phagocytosis is a fundamental process in marine ecosystems by which prey organisms are consumed and their biomass incorporated in food webs or remineralized. However, studies searching for the genes underlying this key ecological process in free-living phagocytizing protists are still scarce, in part due to the lack of appropriate ecological models. Our reanalysis of recent molecular datasets revealed that the cultured heterotrophic flagellate Cafeteria burkhardae is widespread in the global oceans, which prompted us to design a transcriptomics study with this species, grown with the cultured flavobacterium Dokdonia sp. We compared the gene expression between exponential and stationary phases, which were complemented with three starvation by dilution phases that appeared as intermediate states. We found distinct expression profiles in each condition and identified 2056 differentially expressed genes between exponential and stationary samples. Upregulated genes at the exponential phase were related to DNA duplication, transcription and translational machinery, protein remodeling, respiration and phagocytosis, whereas upregulated genes in the stationary phase were involved in signal transduction, cell adhesion, and lipid metabolism. We identified a few highly expressed phagocytosis genes, like peptidases and proton pumps, which could be used to target this ecologically relevant process in marine ecosystems.
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Affiliation(s)
- Ramon Massana
- Institut de Ciències del Mar (CSIC), Passeig Marítim de la Barceloneta 37-49, ES-08003, Barcelona, Catalonia, Spain.
| | - Aurelie Labarre
- Institut de Ciències del Mar (CSIC), Passeig Marítim de la Barceloneta 37-49, ES-08003, Barcelona, Catalonia, Spain
| | - David López-Escardó
- Institut de Ciències del Mar (CSIC), Passeig Marítim de la Barceloneta 37-49, ES-08003, Barcelona, Catalonia, Spain
| | - Aleix Obiol
- Institut de Ciències del Mar (CSIC), Passeig Marítim de la Barceloneta 37-49, ES-08003, Barcelona, Catalonia, Spain
| | - François Bucchini
- Department of Plant Systems Biology, VIB, B-9052, Ghent, Belgium.,Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052, Ghent, Belgium
| | - Thomas Hackl
- Max Planck Institute for Medical Research, 69120, Heidelberg, Germany
| | | | - Klaas Vandepoele
- Department of Plant Systems Biology, VIB, B-9052, Ghent, Belgium.,Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052, Ghent, Belgium
| | - Denis V Tikhonenkov
- Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences, Borok, 152742, Russia
| | - Filip Husnik
- University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
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62
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Anaerobic metabolism of Foraminifera thriving below the seafloor. ISME JOURNAL 2020; 14:2580-2594. [PMID: 32641728 PMCID: PMC7490399 DOI: 10.1038/s41396-020-0708-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 06/09/2020] [Accepted: 06/23/2020] [Indexed: 02/06/2023]
Abstract
Foraminifera are single-celled eukaryotes (protists) of large ecological importance, as well as environmental and paleoenvironmental indicators and biostratigraphic tools. In addition, they are capable of surviving in anoxic marine environments where they represent a major component of the benthic community. However, the cellular adaptations of Foraminifera to the anoxic environment remain poorly constrained. We sampled an oxic-anoxic transition zone in marine sediments from the Namibian shelf, where the genera Bolivina and Stainforthia dominated the Foraminifera community, and use metatranscriptomics to characterize Foraminifera metabolism across the different geochemical conditions. Relative Foraminifera gene expression in anoxic sediment increased an order of magnitude, which was confirmed in a 10-day incubation experiment where the development of anoxia coincided with a 20–40-fold increase in the relative abundance of Foraminifera protein encoding transcripts, attributed primarily to those involved in protein synthesis, intracellular protein trafficking, and modification of the cytoskeleton. This indicated that many Foraminifera were not only surviving but thriving, under the anoxic conditions. The anaerobic energy metabolism of these active Foraminifera was characterized by fermentation of sugars and amino acids, fumarate reduction, and potentially dissimilatory nitrate reduction. Moreover, the gene expression data indicate that under anoxia Foraminifera use the phosphogen creatine phosphate as an ATP store, allowing reserves of high-energy phosphate pool to be maintained for sudden demands of increased energy during anaerobic metabolism. This was co-expressed alongside genes involved in phagocytosis and clathrin-mediated endocytosis (CME). Foraminifera may use CME to utilize dissolved organic matter as a carbon and energy source, in addition to ingestion of prey cells via phagocytosis. These anaerobic metabolic mechanisms help to explain the ecological success of Foraminifera documented in the fossil record since the Cambrian period more than 500 million years ago.
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63
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Santoferrara L, Burki F, Filker S, Logares R, Dunthorn M, McManus GB. Perspectives from Ten Years of Protist Studies by High-Throughput Metabarcoding. J Eukaryot Microbiol 2020; 67:612-622. [PMID: 32498124 DOI: 10.1111/jeu.12813] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 05/29/2020] [Accepted: 05/29/2020] [Indexed: 01/07/2023]
Abstract
During the last decade, high-throughput metabarcoding became routine for analyzing protistan diversity and distributions in nature. Amid a multitude of exciting findings, scientists have also identified and addressed technical and biological limitations, although problems still exist for inference of meaningful taxonomic and ecological knowledge based on short DNA sequences. Given the extensive use of this approach, it is critical to settle our understanding on its strengths and weaknesses and to synthesize up-to-date methodological and conceptual trends. This article summarizes key scientific and technical findings, and identifies current and future directions in protist research that uses metabarcoding.
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Affiliation(s)
- Luciana Santoferrara
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT, USA.,Department of Marine Sciences, University of Connecticut, Groton, CT, USA
| | - Fabien Burki
- Department of Organismal Biology, Program in Systematic Biology, and Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Sabine Filker
- Department of Molecular Ecology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Ramiro Logares
- Institute of Marine Sciences (ICM), CSIC, Barcelona, Spain
| | - Micah Dunthorn
- Department of Eukaryotic Microbiology, University of Duisburg-Essen, Essen, Germany
| | - George B McManus
- Department of Marine Sciences, University of Connecticut, Groton, CT, USA
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64
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Comparative Transcriptomics Reveals Distinct Gene Expressions of a Model Ciliated Protozoa Feeding on Bacteria-Free Medium, Digestible, and Digestion-Resistant Bacteria. Microorganisms 2020; 8:microorganisms8040559. [PMID: 32295093 PMCID: PMC7232342 DOI: 10.3390/microorganisms8040559] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 04/07/2020] [Accepted: 04/11/2020] [Indexed: 01/03/2023] Open
Abstract
Bacterivory is an important ecological function of protists in natural ecosystems. However, there are diverse bacterial species resistant to protistan digestion, which reduces the carbon flow to higher trophic levels. So far, a molecular biological view of metabolic processes in heterotrophic protists during predation of bacterial preys of different digestibility is still lacking. In this study, we investigated the growth performance a ciliated protozoan Tetrahymenathermophila cultivated in a bacteria-free Super Proteose Peptone (SPP) medium (control), and in the media mixed with either a digestion-resistant bacterial species (DRB) or a digestible strain of E. coli (ECO). We found the protist population grew fastest in the SPP and slowest in the DRB treatment. Fluorescence in situ hybridization confirmed that there were indeed non-digested, viable bacteria in the ciliate cells fed with DRB, but none in other treatments. Comparative analysis of RNA-seq data showed that, relative to the control, 637 and 511 genes in T. thermophila were significantly and differentially expressed in the DRB and ECO treatments, respectively. The protistan expression of lysosomal proteases (especially papain-like cysteine proteinases), GH18 chitinases, and an isocitrate lyase were upregulated in both bacterial treatments. The genes encoding protease, glycosidase and involving glycolysis, TCA and glyoxylate cycles of carbon metabolic processes were higher expressed in the DRB treatment when compared with the ECO. Nevertheless, the genes for glutathione metabolism were more upregulated in the control than those in both bacterial treatments, regardless of the digestibility of the bacteria. The results of this study indicate that not only bacterial food but also digestibility of bacterial taxa modulate multiple metabolic processes in heterotrophic protists, which contribute to a better understanding of protistan bacterivory and bacteria-protists interactions on a molecular basis.
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65
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Metegnier G, Paulino S, Ramond P, Siano R, Sourisseau M, Destombe C, Le Gac M. Species specific gene expression dynamics during harmful algal blooms. Sci Rep 2020; 10:6182. [PMID: 32277155 PMCID: PMC7148311 DOI: 10.1038/s41598-020-63326-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 03/20/2020] [Indexed: 01/10/2023] Open
Abstract
Harmful algal blooms are caused by specific members of microbial communities. Understanding the dynamics of these events requires comparing the strategies developed by the problematic species to cope with environmental fluctuations to the ones developed by the other members of the community. During three consecutive years, the meta-transcriptome of micro-eukaryote communities was sequenced during blooms of the toxic dinoflagellate Alexandrium minutum. The dataset was analyzed to investigate species specific gene expression dynamics. Major shifts in gene expression were explained by the succession of different species within the community. Although expression patterns were strongly correlated with fluctuation of the abiotic environment, and more specifically with nutrient concentration, transcripts specifically involved in nutrient uptake and metabolism did not display extensive changes in gene expression. Compared to the other members of the community, A. minutum displayed a very specific expression pattern, with lower expression of photosynthesis transcripts and central metabolism genes (TCA cycle, glucose metabolism, glycolysis…) and contrasting expression pattern of ion transporters across environmental conditions. These results suggest the importance of mixotrophy, cell motility and cell-to-cell interactions during A. minutum blooms.
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Affiliation(s)
- Gabriel Metegnier
- French Research Institute for Exploitation of the Sea, Ifremer DYNECO PELAGOS, 29280, Plouzané, France.,CNRS, Sorbonne Université, UC, UaCh, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, CS 90074, 29688, Roscoff, France
| | - Sauvann Paulino
- French Research Institute for Exploitation of the Sea, Ifremer DYNECO PELAGOS, 29280, Plouzané, France
| | - Pierre Ramond
- French Research Institute for Exploitation of the Sea, Ifremer DYNECO PELAGOS, 29280, Plouzané, France.,CNRS, Sorbonne Université, UMR 7144, Station Biologique de Roscoff, CS90074, 29688, Roscoff Cedex, France
| | - Raffaele Siano
- French Research Institute for Exploitation of the Sea, Ifremer DYNECO PELAGOS, 29280, Plouzané, France
| | - Marc Sourisseau
- French Research Institute for Exploitation of the Sea, Ifremer DYNECO PELAGOS, 29280, Plouzané, France
| | - Christophe Destombe
- CNRS, Sorbonne Université, UC, UaCh, UMI 3614, Evolutionary Biology and Ecology of Algae, Station Biologique de Roscoff, CS 90074, 29688, Roscoff, France
| | - Mickael Le Gac
- French Research Institute for Exploitation of the Sea, Ifremer DYNECO PELAGOS, 29280, Plouzané, France.
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66
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Hennon GMM, Dyhrman ST. Progress and promise of omics for predicting the impacts of climate change on harmful algal blooms. HARMFUL ALGAE 2020; 91:101587. [PMID: 32057337 DOI: 10.1016/j.hal.2019.03.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 03/10/2019] [Indexed: 06/10/2023]
Abstract
Climate change is predicted to increase the severity and prevalence of harmful algal blooms (HABs). In the past twenty years, omics techniques such as genomics, transcriptomics, proteomics and metabolomics have transformed that data landscape of many fields including the study of HABs. Advances in technology have facilitated the creation of many publicly available omics datasets that are complementary and shed new light on the mechanisms of HAB formation and toxin production. Genomics have been used to reveal differences in toxicity and nutritional requirements, while transcriptomics and proteomics have been used to explore HAB species responses to environmental stressors, and metabolomics can reveal mechanisms of allelopathy and toxicity. In this review, we explore how omics data may be leveraged to improve predictions of how climate change will impact HAB dynamics. We also highlight important gaps in our knowledge of HAB prediction, which include swimming behaviors, microbial interactions and evolution that can be addressed by future studies with omics tools. Lastly, we discuss approaches to incorporate current omics datasets into predictive numerical models that may enhance HAB prediction in a changing world. With the ever-increasing omics databases, leveraging these data for understanding climate-driven HAB dynamics will be increasingly powerful.
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Affiliation(s)
- Gwenn M M Hennon
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, United States; College of Fisheries and Ocean Sciences University of Alaska Fairbanks Fairbanks, AK, United States
| | - Sonya T Dyhrman
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, United States; Department of Earth and Environmental Sciences, Columbia University, New York, NY, United States.
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67
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Paez-Espino D, Zhou J, Roux S, Nayfach S, Pavlopoulos GA, Schulz F, McMahon KD, Walsh D, Woyke T, Ivanova NN, Eloe-Fadrosh EA, Tringe SG, Kyrpides NC. Diversity, evolution, and classification of virophages uncovered through global metagenomics. MICROBIOME 2019; 7:157. [PMID: 31823797 PMCID: PMC6905037 DOI: 10.1186/s40168-019-0768-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 11/11/2019] [Indexed: 05/19/2023]
Abstract
BACKGROUND Virophages are small viruses with double-stranded DNA genomes that replicate along with giant viruses and co-infect eukaryotic cells. Due to the paucity of virophage reference genomes, a collective understanding of the global virophage diversity, distribution, and evolution is lacking. RESULTS Here we screened a public collection of over 14,000 metagenomes using the virophage-specific major capsid protein (MCP) as "bait." We identified 44,221 assembled virophage sequences, of which 328 represent high-quality (complete or near-complete) genomes from diverse habitats including the human gut, plant rhizosphere, and terrestrial subsurface. Comparative genomic analysis confirmed the presence of four core genes in a conserved block. We used these genes to establish a revised virophage classification including 27 clades with consistent genome length, gene content, and habitat distribution. Moreover, for eight high-quality virophage genomes, we computationally predicted putative eukaryotic virus hosts. CONCLUSION Overall, our approach has increased the number of known virophage genomes by 10-fold and revealed patterns of genome evolution and global virophage distribution. We anticipate that the expanded diversity presented here will provide the backbone for further virophage studies.
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Affiliation(s)
- David Paez-Espino
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
| | - Jinglie Zhou
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
| | - Simon Roux
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
| | - Stephen Nayfach
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
| | - Georgios A. Pavlopoulos
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
- BSRC “Alexander Fleming”, 34 Fleming Street, Vari, 16672 Athens, Greece
| | - Frederik Schulz
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
| | - Katherine D. McMahon
- Departments of Civil and Environmental Engineering and Bacteriology, University of Wisconsin Madison, 1550 Linden Drive, Madison, WI 53726 USA
| | - David Walsh
- Department of Biology, Concordia University, 7141 Sherbrooke St. West, Montreal, QC, H4B 1R6 Canada
| | - Tanja Woyke
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
| | - Natalia N. Ivanova
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
| | - Emiley A. Eloe-Fadrosh
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
| | - Susannah G. Tringe
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
| | - Nikos C. Kyrpides
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
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68
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Kellogg CTE, McClelland JW, Dunton KH, Crump BC. Strong Seasonality in Arctic Estuarine Microbial Food Webs. Front Microbiol 2019; 10:2628. [PMID: 31849850 PMCID: PMC6896822 DOI: 10.3389/fmicb.2019.02628] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 10/29/2019] [Indexed: 11/17/2022] Open
Abstract
Microbial communities in the coastal Arctic Ocean experience extreme variability in organic matter and inorganic nutrients driven by seasonal shifts in sea ice extent and freshwater inputs. Lagoons border more than half of the Beaufort Sea coast and provide important habitats for migratory fish and seabirds; yet, little is known about the planktonic food webs supporting these higher trophic levels. To investigate seasonal changes in bacterial and protistan planktonic communities, amplicon sequences of 16S and 18S rRNA genes were generated from samples collected during periods of ice-cover (April), ice break-up (June), and open water (August) from shallow lagoons along the eastern Alaska Beaufort Sea coast from 2011 through 2013. Protist communities shifted from heterotrophic to photosynthetic taxa (mainly diatoms) during the winter–spring transition, and then back to a heterotroph-dominated summer community that included dinoflagellates and mixotrophic picophytoplankton such as Micromonas and Bathycoccus. Planktonic parasites belonging to Syndiniales were abundant under ice in winter at a time when allochthonous carbon inputs were low. Bacterial communities shifted from coastal marine taxa (Oceanospirillaceae, Alteromonadales) to estuarine taxa (Polaromonas, Bacteroidetes) during the winter-spring transition, and then to oligotrophic marine taxa (SAR86, SAR92) in summer. Chemolithoautotrophic taxa were abundant under ice, including iron-oxidizing Zetaproteobacteria. These results suggest that wintertime Arctic bacterial communities capitalize on the unique biogeochemical gradients that develop below ice near shore, potentially using chemoautotrophic metabolisms at a time when carbon inputs to the system are low. Co-occurrence networks constructed for each season showed that under-ice networks were dominated by relationships between parasitic protists and other microbial taxa, while spring networks were by far the largest and dominated by bacteria-bacteria co-occurrences. Summer networks were the smallest and least connected, suggesting a more detritus-based food web less reliant on interactions among microbial taxa. Eukaryotic and bacterial community compositions were significantly related to trends in concentrations of stable isotopes of particulate organic carbon and nitrogen, among other physiochemical variables such as dissolved oxygen, salinity, and temperature. This suggests the importance of sea ice cover and terrestrial carbon subsidies in contributing to seasonal trends in microbial communities in the coastal Beaufort Sea.
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Affiliation(s)
| | - James W McClelland
- Marine Science Institute, University of Texas at Austin, Port Aransas, TX, United States
| | - Kenneth H Dunton
- Marine Science Institute, University of Texas at Austin, Port Aransas, TX, United States
| | - Byron C Crump
- College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR, United States
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69
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Ku C, Sebé-Pedrós A. Using single-cell transcriptomics to understand functional states and interactions in microbial eukaryotes. Philos Trans R Soc Lond B Biol Sci 2019; 374:20190098. [PMID: 31587645 PMCID: PMC6792447 DOI: 10.1098/rstb.2019.0098] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/30/2019] [Indexed: 12/13/2022] Open
Abstract
Understanding the diversity and evolution of eukaryotic microorganisms remains one of the major challenges of modern biology. In recent years, we have advanced in the discovery and phylogenetic placement of new eukaryotic species and lineages, which in turn completely transformed our view on the eukaryotic tree of life. But we remain ignorant of the life cycles, physiology and cellular states of most of these microbial eukaryotes, as well as of their interactions with other organisms. Here, we discuss how high-throughput genome-wide gene expression analysis of eukaryotic single cells can shed light on protist biology. First, we review different single-cell transcriptomics methodologies with particular focus on microbial eukaryote applications. Then, we discuss single-cell gene expression analysis of protists in culture and what can be learnt from these approaches. Finally, we envision the application of single-cell transcriptomics to protist communities to interrogate not only community components, but also the gene expression signatures of distinct cellular and physiological states, as well as the transcriptional dynamics of interspecific interactions. Overall, we argue that single-cell transcriptomics can significantly contribute to our understanding of the biology of microbial eukaryotes. This article is part of a discussion meeting issue 'Single cell ecology'.
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Affiliation(s)
- Chuan Ku
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Arnau Sebé-Pedrós
- Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona 08003, Spain
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70
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Bjorbækmo MFM, Evenstad A, Røsæg LL, Krabberød AK, Logares R. The planktonic protist interactome: where do we stand after a century of research? ISME JOURNAL 2019; 14:544-559. [PMID: 31685936 PMCID: PMC6976576 DOI: 10.1038/s41396-019-0542-5] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 09/17/2019] [Accepted: 09/24/2019] [Indexed: 12/16/2022]
Abstract
Microbial interactions are crucial for Earth ecosystem function, but our knowledge about them is limited and has so far mainly existed as scattered records. Here, we have surveyed the literature involving planktonic protist interactions and gathered the information in a manually curated Protist Interaction DAtabase (PIDA). In total, we have registered ~2500 ecological interactions from ~500 publications, spanning the last 150 years. All major protistan lineages were involved in interactions as hosts, symbionts (mutualists and commensalists), parasites, predators, and/or prey. Predation was the most common interaction (39% of all records), followed by symbiosis (29%), parasitism (18%), and ‘unresolved interactions’ (14%, where it is uncertain whether the interaction is beneficial or antagonistic). Using bipartite networks, we found that protist predators seem to be ‘multivorous’ while parasite–host and symbiont–host interactions appear to have moderate degrees of specialization. The SAR supergroup (i.e., Stramenopiles, Alveolata, and Rhizaria) heavily dominated PIDA, and comparisons against a global-ocean molecular survey (TARA Oceans) indicated that several SAR lineages, which are abundant and diverse in the marine realm, were underrepresented among the recorded interactions. Despite historical biases, our work not only unveils large-scale eco-evolutionary trends in the protist interactome, but it also constitutes an expandable resource to investigate protist interactions and to test hypotheses deriving from omics tools.
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Affiliation(s)
- Marit F Markussen Bjorbækmo
- Department of Biosciences, Section for Genetics and Evolutionary Biology (Evogene), University of Oslo, Blindernv. 31, N-0316, Oslo, Norway
| | - Andreas Evenstad
- Department of Biosciences, Section for Genetics and Evolutionary Biology (Evogene), University of Oslo, Blindernv. 31, N-0316, Oslo, Norway
| | - Line Lieblein Røsæg
- Department of Biosciences, Section for Genetics and Evolutionary Biology (Evogene), University of Oslo, Blindernv. 31, N-0316, Oslo, Norway
| | - Anders K Krabberød
- Department of Biosciences, Section for Genetics and Evolutionary Biology (Evogene), University of Oslo, Blindernv. 31, N-0316, Oslo, Norway.
| | - Ramiro Logares
- Department of Biosciences, Section for Genetics and Evolutionary Biology (Evogene), University of Oslo, Blindernv. 31, N-0316, Oslo, Norway. .,Institut de Ciències del Mar (CSIC), Passeig Marítim de la Barceloneta, 37-49, ES-08003, Barcelona, Catalonia, Spain.
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71
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Zimmerman AE, Bachy C, Ma X, Roux S, Jang HB, Sullivan MB, Waldbauer JR, Worden AZ. Closely related viruses of the marine picoeukaryotic alga Ostreococcus lucimarinus exhibit different ecological strategies. Environ Microbiol 2019; 21:2148-2170. [PMID: 30924271 PMCID: PMC6851583 DOI: 10.1111/1462-2920.14608] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 03/16/2019] [Accepted: 03/23/2019] [Indexed: 01/01/2023]
Abstract
In marine ecosystems, viruses are major disrupters of the direct flow of carbon and nutrients to higher trophic levels. Although the genetic diversity of several eukaryotic phytoplankton virus groups has been characterized, their infection dynamics are less understood, such that the physiological and ecological implications of their diversity remain unclear. We compared genomes and infection phenotypes of the two most closely related cultured phycodnaviruses infecting the widespread picoprasinophyte Ostreococcus lucimarinus under standard- (1.3 divisions per day) and limited-light (0.41 divisions per day) nutrient replete conditions. OlV7 infection caused early arrest of the host cell cycle, coinciding with a significantly higher proportion of infected cells than OlV1-amended treatments, regardless of host growth rate. OlV7 treatments showed a near-50-fold increase of progeny virions at the higher host growth rate, contrasting with OlV1's 16-fold increase. However, production of OlV7 virions was more sensitive than OlV1 production to reduced host growth rate, suggesting fitness trade-offs between infection efficiency and resilience to host physiology. Moreover, although organic matter released from OlV1- and OlV7-infected hosts had broadly similar chemical composition, some distinct molecular signatures were observed. Collectively, these results suggest that current views on viral relatedness through marker and core gene analyses underplay operational divergence and consequences for host ecology.
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Affiliation(s)
| | - Charles Bachy
- Monterey Bay Aquarium Research InstituteMoss LandingCAUSA
| | - Xiufeng Ma
- Department of the Geophysical SciencesUniversity of ChicagoChicagoILUSA
| | - Simon Roux
- Department of MicrobiologyEnvironmental and Geodetic Engineering, The Ohio State UniversityColumbusOHUSA
| | - Ho Bin Jang
- Department of MicrobiologyEnvironmental and Geodetic Engineering, The Ohio State UniversityColumbusOHUSA
- Department of CivilEnvironmental and Geodetic Engineering, The Ohio State UniversityColumbusOHUSA
| | - Matthew B. Sullivan
- Department of MicrobiologyEnvironmental and Geodetic Engineering, The Ohio State UniversityColumbusOHUSA
- Department of CivilEnvironmental and Geodetic Engineering, The Ohio State UniversityColumbusOHUSA
| | | | - Alexandra Z. Worden
- Monterey Bay Aquarium Research InstituteMoss LandingCAUSA
- Ocean EcoSystems Biology Unit, Marine Ecology DivisionGEOMAR Helmholtz Centre for Ocean Research KielKielDE
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72
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Molecular mechanisms of temperature acclimation and adaptation in marine diatoms. ISME JOURNAL 2019; 13:2415-2425. [PMID: 31127177 DOI: 10.1038/s41396-019-0441-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 04/16/2019] [Accepted: 05/03/2019] [Indexed: 12/21/2022]
Abstract
Diatoms are important contributors to marine primary production and the ocean carbon cycle, yet the molecular mechanisms that regulate their acclimation and adaptation to temperature are poorly understood. Here we use a transcriptomic approach to investigate the molecular mechanisms associated with temperature acclimation and adaptation in closely related colder- and warmer-adapted diatom species. We find evidence that evolutionary changes in baseline gene expression, which we termed transcriptional investment or divestment, is a key mechanism used by diatoms to adapt to different growth temperatures. Invested and divested pathways indicate that the maintenance of protein processing machinery and membrane structure, important short-term physiological mechanisms used to respond to temperature changes, are key elements associated with adaptation to different growth temperatures. Our results also indicate that evolutionary changes in the transcriptional regulation of acetyl-CoA associated pathways, including lipid and branched chain amino acid metabolism, are used by diatoms to balance photosynthetic light capture and metabolism with changes in growth temperature. Transcriptional investment and divestment can provide a framework to identify mechanisms of acclimation and adaption to temperature.
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73
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Johnson LK, Alexander H, Brown CT. Re-assembly, quality evaluation, and annotation of 678 microbial eukaryotic reference transcriptomes. Gigascience 2019; 8:giy158. [PMID: 30544207 PMCID: PMC6481552 DOI: 10.1093/gigascience/giy158] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 09/18/2018] [Accepted: 11/29/2018] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND De novo transcriptome assemblies are required prior to analyzing RNA sequencing data from a species without an existing reference genome or transcriptome. Despite the prevalence of transcriptomic studies, the effects of using different workflows, or "pipelines," on the resulting assemblies are poorly understood. Here, a pipeline was programmatically automated and used to assemble and annotate raw transcriptomic short-read data collected as part of the Marine Microbial Eukaryotic Transcriptome Sequencing Project. The resulting transcriptome assemblies were evaluated and compared against assemblies that were previously generated with a different pipeline developed by the National Center for Genome Research. RESULTS New transcriptome assemblies contained the majority of previous contigs as well as new content. On average, 7.8% of the annotated contigs in the new assemblies were novel gene names not found in the previous assemblies. Taxonomic trends were observed in the assembly metrics. Assemblies from the Dinoflagellata showed a higher number of contigs and unique k-mers than transcriptomes from other phyla, while assemblies from Ciliophora had a lower percentage of open reading frames compared to other phyla. CONCLUSIONS Given current bioinformatics approaches, there is no single "best" reference transcriptome for a particular set of raw data. As the optimum transcriptome is a moving target, improving (or not) with new tools and approaches, automated and programmable pipelines are invaluable for managing the computationally intensive tasks required for re-processing large sets of samples with revised pipelines and ensuring a common evaluation workflow is applied to all samples. Thus, re-assembling existing data with new tools using automated and programmable pipelines may yield more accurate identification of taxon-specific trends across samples in addition to novel and useful products for the community.
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Affiliation(s)
- Lisa K Johnson
- Department of Population Health, and Reproduction, School of Veterinary Medicine, University of California Davis, One Shields Ave, Davis, CA 95616, USA
- Molecular, Cellular, and Integrative Physiology Graduate Group, University of California Davis, One Shields Ave, Davis, CA 95616, USA
| | - Harriet Alexander
- Department of Population Health, and Reproduction, School of Veterinary Medicine, University of California Davis, One Shields Ave, Davis, CA 95616, USA
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
| | - C Titus Brown
- Department of Population Health, and Reproduction, School of Veterinary Medicine, University of California Davis, One Shields Ave, Davis, CA 95616, USA
- Molecular, Cellular, and Integrative Physiology Graduate Group, University of California Davis, One Shields Ave, Davis, CA 95616, USA
- Genome Center, University of California Davis, 451 Health Sciences Dr, Davis, CA 95616, USA
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74
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Mars Brisbin M, Mitarai S. Differential Gene Expression Supports a Resource-Intensive, Defensive Role for Colony Production in the Bloom-Forming Haptophyte, Phaeocystis globosa. J Eukaryot Microbiol 2019; 66:788-801. [PMID: 30860641 PMCID: PMC6766888 DOI: 10.1111/jeu.12727] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 01/23/2019] [Accepted: 02/28/2019] [Indexed: 12/22/2022]
Abstract
Phaeocystis globosa forms dense, monospecific blooms in temperate, northern waters. Blooms are usually dominated by the colonial morphotype—nonflagellated cells embedded in a secreted mucilaginous mass. Colonial Phaeocystis blooms significantly affect food‐web structure and function and negatively impact fisheries and aquaculture, but factors regulating colony formation remain enigmatic. Destructive P. globosa blooms have been reported in tropical and subtropical regions more recently and warm‐water blooms could become more common with continued climate change and coastal eutrophication. We therefore assessed genetic pathways associated with colony formation by investigating differential gene expression between colonial and solitary cells of a warm‐water P. globosa strain. Our results illustrate a transcriptional shift in colonial cells with most of the differentially expressed genes downregulated, supporting a reallocation of resources associated with forming and maintaining colonies. Dimethylsulfide and acrylate production and pathogen interaction pathways were upregulated in colonial cells, suggesting a defensive role for producing colonies. We identify several protein kinase signaling pathways that may influence the transition between morphotypes, providing targets for future research into factors affecting colony formation. This study provides novel insights into genetic mechanisms involved in Phaeocystis colony formation and provides new evidence supporting a defensive role for Phaeocystis colonies.
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Affiliation(s)
- Margaret Mars Brisbin
- Marine Biophysics Unit, Okinawa Institute of Science and Technology Graduate University, Onna-Son, Japan
| | - Satoshi Mitarai
- Marine Biophysics Unit, Okinawa Institute of Science and Technology Graduate University, Onna-Son, Japan
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75
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Cohen Y, Pasternak Z, Johnke J, Abed‐Rabbo A, Kushmaro A, Chatzinotas A, Jurkevitch E. Bacteria and microeukaryotes are differentially segregated in sympatric wastewater microhabitats. Environ Microbiol 2019; 21:1757-1770. [DOI: 10.1111/1462-2920.14548] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 01/20/2019] [Accepted: 01/28/2019] [Indexed: 01/22/2023]
Affiliation(s)
- Yossi Cohen
- Department of Plant Pathology and Microbiology, Faculty of Agriculture, Food and EnvironmentThe Hebrew University of Jerusalem Rehovot, 76100 Israel
| | - Zohar Pasternak
- Department of Plant Pathology and Microbiology, Faculty of Agriculture, Food and EnvironmentThe Hebrew University of Jerusalem Rehovot, 76100 Israel
| | - Julia Johnke
- Department of Environmental MicrobiologyHelmholtz Centre for Environmental Research – UFZ Permoserstrasse 15, Leipzig, 04318 Germany
| | - Alfred Abed‐Rabbo
- Faculty of ScienceBethlehem University, Palestinian National Authority, Bethlehem, Israel
| | - Ariel Kushmaro
- Avram and Stella Goldstein‐Goren, The Department of Biotechnology Engineering, Faculty of Engineering SciencesBen‐Gurion University of the Negev P.O. Box 653, Beer‐Sheva Israel
- The Ilse Katz Centre for Meso and Nanoscale Science and TechnologyBen‐Gurion University of the Negev Beer‐Sheva Israel
| | - Antonis Chatzinotas
- Department of Environmental MicrobiologyHelmholtz Centre for Environmental Research – UFZ Permoserstrasse 15, Leipzig, 04318 Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig Deutscher Platz 5e, Leipzig, 04103 Germany
| | - Edouard Jurkevitch
- Department of Plant Pathology and Microbiology, Faculty of Agriculture, Food and EnvironmentThe Hebrew University of Jerusalem Rehovot, 76100 Israel
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76
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Graupner N, Jensen M, Bock C, Marks S, Rahmann S, Beisser D, Boenigk J. Evolution of heterotrophy in chrysophytes as reflected by comparative transcriptomics. FEMS Microbiol Ecol 2019. [PMID: 29518196 PMCID: PMC6019013 DOI: 10.1093/femsec/fiy039] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Shifts in the nutritional mode between phototrophy, mixotrophy and heterotrophy are a widespread phenomenon in the evolution of eukaryotic diversity. The transition between nutritional modes is particularly pronounced in chrysophytes and occurred independently several times through parallel evolution. Thus, chrysophytes provide a unique opportunity for studying the molecular basis of nutritional diversification and of the accompanying pathway reduction and degradation of plastid structures. In order to analyze the succession in switching the nutritional mode from mixotrophy to heterotrophy, we compared the transcriptome of the mixotrophic Poterioochromonas malhamensis with the transcriptomes of three obligate heterotrophic species of Ochromonadales. We used the transcriptome of P. malhamensis as a reference for plastid reduction in the heterotrophic taxa. The analyzed heterotrophic taxa were in different stages of plastid reduction. We investigated the reduction of several photosynthesis related pathways e.g. the xanthophyll cycle, the mevalonate pathway, the shikimate pathway and the tryptophan biosynthesis as well as the reduction of plastid structures and postulate a presumable succession of pathway reduction and degradation of accompanying structures.
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Affiliation(s)
- Nadine Graupner
- Biodiversity, Faculty of Biology, University of Duisburg-Essen, Universitätsstr. 5, D-45141 Essen, Germany
| | - Manfred Jensen
- Biodiversity, Faculty of Biology, University of Duisburg-Essen, Universitätsstr. 5, D-45141 Essen, Germany
| | - Christina Bock
- Biodiversity, Faculty of Biology, University of Duisburg-Essen, Universitätsstr. 5, D-45141 Essen, Germany
| | - Sabina Marks
- Biodiversity, Faculty of Biology, University of Duisburg-Essen, Universitätsstr. 5, D-45141 Essen, Germany
| | - Sven Rahmann
- Genome Informatics, Institute of Human Genetics, University of Duisburg-Essen, University Hospital Essen, Hufelandstr. 55, D-45147 Essen, Germany
| | - Daniela Beisser
- Biodiversity, Faculty of Biology, University of Duisburg-Essen, Universitätsstr. 5, D-45141 Essen, Germany
| | - Jens Boenigk
- Biodiversity, Faculty of Biology, University of Duisburg-Essen, Universitätsstr. 5, D-45141 Essen, Germany.,Centre for Water and Environmental Research (ZWU), University of Duisburg-Essen, Universitätsstr. 2, D-45141 Essen, Germany
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77
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Ujiié Y, Kimoto K, Ishimura T. Advanced approach to analyzing calcareous protists for present and past pelagic ecology: Comprehensive analysis of 3D-morphology, stable isotopes, and genes of planktic foraminifers. PLoS One 2019; 14:e0213282. [PMID: 30845272 PMCID: PMC6405064 DOI: 10.1371/journal.pone.0213282] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 02/18/2019] [Indexed: 11/18/2022] Open
Abstract
Marine protists play an important role in oceanic ecosystems and biogeochemical cycles. However, the difficulties in culturing pelagic protists indicate that their ecology and behavior remain poorly understood; phylogeographic studies based on single-cell genetic analyses have often shown that they are highly divergent at the biological species level, with variable geographic distributions. This indicates that their ecology could be complex. On the other hand, the biomineral (calcareous) shells of planktic foraminifers are widely used in geochemical analyses to estimate marine paleoenvironmental characteristics (i.e., temperature), because the shell chemical composition reflects ambient seawater conditions. Among the pelagic protists, planktic foraminifers are ideal study candidates to develop a combined approach of genetic, morphological, and geochemical methods, thus reflecting environmental and ecological characteristics. The present study precisely tested whether the DNA extraction process physically and chemically affects the shells of the planktic foraminifer Globigerinoides ruber. We used a nondestructive method for analyzing physical changes (micro-focus X-ray computed tomography (MXCT) scanning) to compare specimens at the pre- and post-DNA extraction stages. Our results demonstrate that DNA extraction has no significant effect on shell density and thickness. We measured stable carbon and oxygen isotopes on the shell of each individual in a negative control or one of two DNA-extracted groups and detected no significant differences in isotopic values among the three groups. Moreover, we evaluated isotopic variations at the biological species level with regard to their ecological characteristics such as depth habitat, life stages, and symbionts. Thus, our examination of the physiochemical effects on biomineral shells through DNA extraction shows that morphological and isotopic analyses of foraminifers can be combined with genetic analysis. These analytical methods are applicable to other shell-forming protists and microorganisms. In this study, we developed a powerful analytical tool for use in ecological and environmental studies of modern and past oceans.
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Affiliation(s)
- Yurika Ujiié
- Center for Advanced Marine Core Research, Kochi University, Nankoku, Japan
- * E-mail:
| | - Katsunori Kimoto
- Research and Development Center for Global Change, JAMSTEC, Yokosuka, Japan
| | - Toyoho Ishimura
- National Institute of Technology, Ibaraki College, Hitachinaka, Japan
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78
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Decelle J, Stryhanyuk H, Gallet B, Veronesi G, Schmidt M, Balzano S, Marro S, Uwizeye C, Jouneau PH, Lupette J, Jouhet J, Maréchal E, Schwab Y, Schieber NL, Tucoulou R, Richnow H, Finazzi G, Musat N. Algal Remodeling in a Ubiquitous Planktonic Photosymbiosis. Curr Biol 2019; 29:968-978.e4. [PMID: 30827917 DOI: 10.1016/j.cub.2019.01.073] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Revised: 12/03/2018] [Accepted: 01/28/2019] [Indexed: 01/12/2023]
Abstract
Photosymbiosis between single-celled hosts and microalgae is common in oceanic plankton, especially in oligotrophic surface waters. However, the functioning of this ecologically important cell-cell interaction and the subcellular mechanisms allowing the host to accommodate and benefit from its microalgae remain enigmatic. Here, using a combination of quantitative single-cell structural and chemical imaging techniques (FIB-SEM, nanoSIMS, Synchrotron X-ray fluorescence), we show that the structural organization, physiology, and trophic status of the algal symbionts (the haptophyte Phaeocystis) significantly change within their acantharian hosts compared to their free-living phase in culture. In symbiosis, algal cell division is blocked, photosynthesis is enhanced, and cell volume is increased by up to 10-fold with a higher number of plastids (from 2 to up to 30) and thylakoid membranes. The multiplication of plastids can lead to a 38-fold increase of the total plastid volume in a cell. Subcellular mapping of nutrients (nitrogen and phosphorous) and their stoichiometric ratios shows that symbiotic algae are impoverished in phosphorous and suggests a higher investment in energy-acquisition machinery rather than in growth. Nanoscale imaging also showed that the host supplies a substantial amount of trace metals (e.g., iron and cobalt), which are stored in algal vacuoles at high concentrations (up to 660 ppm). Sulfur mapping reveals a high concentration in algal vacuoles that may be a source of antioxidant molecules. Overall, this study unveils an unprecedented morphological and metabolic transformation of microalgae following their integration into a host, and it suggests that this widespread symbiosis is a farming strategy wherein the host engulfs and exploits microalgae.
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Affiliation(s)
- Johan Decelle
- Helmholtz Centre for Environmental Research - UFZ, Department of Isotope Biogeochemistry, 04318 Leipzig, Germany.
| | - Hryhoriy Stryhanyuk
- Helmholtz Centre for Environmental Research - UFZ, Department of Isotope Biogeochemistry, 04318 Leipzig, Germany
| | - Benoit Gallet
- Institut de Biologie Structurale, Université Grenoble Alpes, CNRS, CEA, 71 Avenue des Martyrs, 38044 Grenoble, France
| | - Giulia Veronesi
- Laboratoire de Chimie et Biologie des Métaux UMR 5249, Université Grenoble Alpes, CNRS, CEA, 17 Avenue des Martyrs, 38054 Grenoble, France; ESRF, The European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38043 Grenoble, France
| | - Matthias Schmidt
- Helmholtz Centre for Environmental Research - UFZ, Department of Isotope Biogeochemistry, 04318 Leipzig, Germany
| | - Sergio Balzano
- NIOZ, Royal Netherlands Institute for Sea Research, Department of Marine Microbiology and Biogeochemistry, and Utrecht University, PO Box 59, 1790 AB Den Burg, the Netherlands
| | - Sophie Marro
- Sorbonne Universités, UPMC Université Paris 06, CNRS, Laboratoire d'Océanographie de Villefranche UMR7093, Observatoire Océanologique, 06230 Villefranche-sur-Mer, France
| | - Clarisse Uwizeye
- Cell & Plant Physiology Laboratory, University of Grenoble Alpes, CNRS, CEA, INRA, 38054 Grenoble Cedex 9, France
| | - Pierre-Henri Jouneau
- Institut Nanosciences et Cryogénie, Université Grenoble Alpes, CEA, 38054 Grenoble, France
| | - Josselin Lupette
- Cell & Plant Physiology Laboratory, University of Grenoble Alpes, CNRS, CEA, INRA, 38054 Grenoble Cedex 9, France
| | - Juliette Jouhet
- Cell & Plant Physiology Laboratory, University of Grenoble Alpes, CNRS, CEA, INRA, 38054 Grenoble Cedex 9, France
| | - Eric Maréchal
- Cell & Plant Physiology Laboratory, University of Grenoble Alpes, CNRS, CEA, INRA, 38054 Grenoble Cedex 9, France
| | - Yannick Schwab
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, 69117 Heidelberg, Germany
| | - Nicole L Schieber
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, 69117 Heidelberg, Germany
| | - Rémi Tucoulou
- ESRF, The European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38043 Grenoble, France
| | - Hans Richnow
- Helmholtz Centre for Environmental Research - UFZ, Department of Isotope Biogeochemistry, 04318 Leipzig, Germany
| | - Giovanni Finazzi
- Cell & Plant Physiology Laboratory, University of Grenoble Alpes, CNRS, CEA, INRA, 38054 Grenoble Cedex 9, France
| | - Niculina Musat
- Helmholtz Centre for Environmental Research - UFZ, Department of Isotope Biogeochemistry, 04318 Leipzig, Germany
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79
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Alexander H, Johnson LK, Brown CT. Keeping it light: (re)analyzing community-wide datasets without major infrastructure. Gigascience 2019; 8:5241892. [PMID: 30544142 PMCID: PMC6350038 DOI: 10.1093/gigascience/giy159] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 11/29/2018] [Indexed: 12/19/2022] Open
Abstract
DNA sequencing technology has revolutionized the field of biology, shifting biology from a data-limited to data-rich state. Central to the interpretation of sequencing data are the computational tools and approaches that convert raw data into biologically meaningful information. Both the tools and the generation of data are actively evolving, yet the practice of re-analysis of previously generated data with new tools is not commonplace. Re-analysis of existing data provides an affordable means of generating new information and will likely become more routine within biology, yet necessitates a new set of considerations for best practices and resource development. Here, we discuss several practices that we believe to be broadly applicable when re-analyzing data, especially when done by small research groups.
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Affiliation(s)
- Harriet Alexander
- Population Health and Reproduction, University of California Davis, 1 Shields Ave., Davis, CA, 95616, USA.,Biology Department, Woods Hole Oceanographic Institution, 266 Woods Hole Rd., Woods Hole, MA, 02543, USA
| | - Lisa K Johnson
- Population Health and Reproduction, University of California Davis, 1 Shields Ave., Davis, CA, 95616, USA.,Molecular, Cellular, and Integrative Physiology Graduate Group, University of California Davis, 1 Shields Ave., Davis, CA, 95616, USA
| | - C Titus Brown
- Population Health and Reproduction, University of California Davis, 1 Shields Ave., Davis, CA, 95616, USA.,Molecular, Cellular, and Integrative Physiology Graduate Group, University of California Davis, 1 Shields Ave., Davis, CA, 95616, USA.,Genome Center, University of California Davis, 1 Shields Ave, Davis, CA, 95616, USA
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80
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81
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Bai M, Sen B, Wang Q, Xie Y, He Y, Wang G. Molecular Detection and Spatiotemporal Characterization of Labyrinthulomycete Protist Diversity in the Coastal Waters Along the Pearl River Delta. MICROBIAL ECOLOGY 2019; 77:394-405. [PMID: 30083828 DOI: 10.1007/s00248-018-1235-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 07/16/2018] [Indexed: 06/08/2023]
Abstract
The heterotrophic labyrinthulomycete protists have long been known to play an important role in the nutrient cycling of coastal seawater. Yet, their spatiotemporal abundance and diversity in polluted coastal waters remain poorly discussed, due in part to the paucity of a rapid detection method. To this end, we developed a qPCR detection method based on a newly designed primer pair targeting their 18S rRNA gene. Using this method, we studied the population dynamics of labyrinthulomycete protists in nutrient-rich (Shenzhen Bay) and low-nutrient (Daya) coastal habitats along the Pearl River Delta. We found a significantly (P < 0.05) higher abundance of Labyrinthulomycetes in the Shenzhen bay (average 3455 gene copies mL-1) than that in Daya Bay (average 378 gene copies mL-1). Their abundance gradient positively correlated (P < 0.05) with the levels of inorganic nitrogen and phosphates. Further characterization of the molecular diversity of these protists in Shenzhen Bay using different primer sets revealed the presence of several genera besides a large number of unclassified OTUs. Regardless of the primer biases, our results show significant (P < 0.05) spatiotemporal changes in the molecular abundance and diversity of these heterotrophic protists. Overall, this study provides a rapid molecular detection tool for Labyrinthulomycetes and expands our current understanding of their dynamics controlled by physicochemical gradients in coastal waters.
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Affiliation(s)
- 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
| | - Qiuzhen Wang
- 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
| | - Yaodong He
- 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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82
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Faure E, Not F, Benoiston AS, Labadie K, Bittner L, Ayata SD. Mixotrophic protists display contrasted biogeographies in the global ocean. ISME JOURNAL 2019; 13:1072-1083. [PMID: 30643201 DOI: 10.1038/s41396-018-0340-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 12/13/2018] [Accepted: 12/13/2018] [Indexed: 12/21/2022]
Abstract
Mixotrophy, or the ability to acquire carbon from both auto- and heterotrophy, is a widespread ecological trait in marine protists. Using a metabarcoding dataset of marine plankton from the global ocean, 318,054 mixotrophic metabarcodes represented by 89,951,866 sequences and belonging to 133 taxonomic lineages were identified and classified into four mixotrophic functional types: constitutive mixotrophs (CM), generalist non-constitutive mixotrophs (GNCM), endo-symbiotic specialist non-constitutive mixotrophs (eSNCM), and plastidic specialist non-constitutive mixotrophs (pSNCM). Mixotrophy appeared ubiquitous, and the distributions of the four mixotypes were analyzed to identify the abiotic factors shaping their biogeographies. Kleptoplastidic mixotrophs (GNCM and pSNCM) were detected in new zones compared to previous morphological studies. Constitutive and non-constitutive mixotrophs had similar ranges of distributions. Most lineages were evenly found in the samples, yet some of them displayed strongly contrasted distributions, both across and within mixotypes. Particularly divergent biogeographies were found within endo-symbiotic mixotrophs, depending on the ability to form colonies or the mode of symbiosis. We showed how metabarcoding can be used in a complementary way with previous morphological observations to study the biogeography of mixotrophic protists and to identify key drivers of their biogeography.
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Affiliation(s)
- Emile Faure
- Sorbonne Université, CNRS, Laboratoire d'océanographie de Villefranche, LOV, 06230, Villefranche-sur-Mer, France. .,Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum national d'Histoire naturelle, CNRS, Sorbonne Université, EPHE, CP 50, 57 rue Cuvier, 75005, Paris, France.
| | - Fabrice Not
- Sorbonne Université, CNRS, UMR7144 Adaptation and Diversity in Marine Environment (AD2M) Laboratory, Ecology of Marine Plankton team, Station Biologique de Roscoff, Place Georges Teissier, 29680, Roscoff, France
| | - Anne-Sophie Benoiston
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum national d'Histoire naturelle, CNRS, Sorbonne Université, EPHE, CP 50, 57 rue Cuvier, 75005, Paris, France
| | - Karine Labadie
- Genoscope, Institut de biologie François-Jacob, Commissariat à l'Energie Atomique (CEA), Evry, France, 91057, Evry, France
| | - Lucie Bittner
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum national d'Histoire naturelle, CNRS, Sorbonne Université, EPHE, CP 50, 57 rue Cuvier, 75005, Paris, France
| | - Sakina-Dorothée Ayata
- Sorbonne Université, CNRS, Laboratoire d'océanographie de Villefranche, LOV, 06230, Villefranche-sur-Mer, France.,Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum national d'Histoire naturelle, CNRS, Sorbonne Université, EPHE, CP 50, 57 rue Cuvier, 75005, Paris, France
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83
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Abstract
Organisms display astonishing levels of cell and molecular diversity, including genome size, shape, and architecture. In this chapter, we review how the genome can be viewed as both a structural and an informational unit of biological diversity and explicitly define our intended meaning of genetic information. A brief overview of the characteristic features of bacterial, archaeal, and eukaryotic cell types and viruses sets the stage for a review of the differences in organization, size, and packaging strategies of their genomes. We include a detailed review of genetic elements found outside the primary chromosomal structures, as these provide insights into how genomes are sometimes viewed as incomplete informational entities. Lastly, we reassess the definition of the genome in light of recent advancements in our understanding of the diversity of genomic structures and the mechanisms by which genetic information is expressed within the cell. Collectively, these topics comprise a good introduction to genome biology for the newcomer to the field and provide a valuable reference for those developing new statistical or computation methods in genomics. This review also prepares the reader for anticipated transformations in thinking as the field of genome biology progresses.
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84
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Abstract
Diatoms are prominent eukaryotic phytoplankton despite being limited by the micronutrient iron in vast expanses of the ocean. As iron inputs are often sporadic, diatoms have evolved mechanisms such as the ability to store iron that enable them to bloom when iron is resupplied and then persist when low iron levels are reinstated. Two iron storage mechanisms have been previously described: the protein ferritin and vacuolar storage. To investigate the ecological role of these mechanisms among diatoms, iron addition and removal incubations were conducted using natural phytoplankton communities from varying iron environments. We show that among the predominant diatoms, Pseudo-nitzschia were favored by iron removal and displayed unique ferritin expression consistent with a long-term storage function. Meanwhile, Chaetoceros and Thalassiosira gene expression aligned with vacuolar storage mechanisms. Pseudo-nitzschia also showed exceptionally high iron storage under steady-state high and low iron conditions, as well as following iron resupply to iron-limited cells. We propose that bloom-forming diatoms use different iron storage mechanisms and that ferritin utilization may provide an advantage in areas of prolonged iron limitation with pulsed iron inputs. As iron distributions and availability change, this speculated ferritin-linked advantage may result in shifts in diatom community composition that can alter marine ecosystems and biogeochemical cycles.
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85
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Caron DA, Hu SK. Are We Overestimating Protistan Diversity in Nature? Trends Microbiol 2018; 27:197-205. [PMID: 30455081 DOI: 10.1016/j.tim.2018.10.009] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Revised: 10/04/2018] [Accepted: 10/25/2018] [Indexed: 12/30/2022]
Abstract
Documenting the immense diversity of single-celled, eukaryotic organisms (protists) has been a formidable challenge for ecologists. These species were originally defined by morphological criteria, but shortcomings of the morphospecies concept, and a bewildering array of sizes and cellular attributes, has made constructing a taxonomy that is useful for ecologists nearly impossible. Consequently, physiological and genetic information has been integrated to address these shortcomings, and to develop the framework of a unifying taxonomy. DNA sequence information, in particular, has revolutionized studies of protistan diversity. However, the exponential increase in sequence-based protistan species richness published from field surveys in recent years raises the question of whether we have moved beyond characterizing species-level diversity and begun to reveal intraspecies diversity. The answer to that question appears to be 'yes', at least for some protistan lineages. The need to document such microdiversity may be justified, but it is important for protistologists to recognize and acknowledge that possibility, and its consequences.
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Affiliation(s)
- David A Caron
- Department of Biological Sciences, 3616 Trousdale Parkway, University of Southern California, Los Angeles, CA 90089-0371, USA.
| | - Sarah K Hu
- Department of Biological Sciences, 3616 Trousdale Parkway, University of Southern California, Los Angeles, CA 90089-0371, USA
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86
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Hemimastigophora is a novel supra-kingdom-level lineage of eukaryotes. Nature 2018; 564:410-414. [PMID: 30429611 DOI: 10.1038/s41586-018-0708-8] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 09/21/2018] [Indexed: 12/11/2022]
Abstract
Almost all eukaryote life forms have now been placed within one of five to eight supra-kingdom-level groups using molecular phylogenetics1-4. The 'phylum' Hemimastigophora is probably the most distinctive morphologically defined lineage that still awaits such a phylogenetic assignment. First observed in the nineteenth century, hemimastigotes are free-living predatory protists with two rows of flagella and a unique cell architecture5-7; to our knowledge, no molecular sequence data or cultures are currently available for this group. Here we report phylogenomic analyses based on high-coverage, cultivation-independent transcriptomics that place Hemimastigophora outside of all established eukaryote supergroups. They instead comprise an independent supra-kingdom-level lineage that most likely forms a sister clade to the 'Diaphoretickes' half of eukaryote diversity (that is, the 'stramenopiles, alveolates and Rhizaria' supergroup (Sar), Archaeplastida and Cryptista, as well as other major groups). The previous ranking of Hemimastigophora as a phylum understates the evolutionary distinctiveness of this group, which has considerable importance for investigations into the deep-level evolutionary history of eukaryotic life-ranging from understanding the origins of fundamental cell systems to placing the root of the tree. We have also established the first culture of a hemimastigote (Hemimastix kukwesjijk sp. nov.), which will facilitate future genomic and cell-biological investigations into eukaryote evolution and the last eukaryotic common ancestor.
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87
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Lampe RH, Cohen NR, Ellis KA, Bruland KW, Maldonado MT, Peterson TD, Till CP, Brzezinski MA, Bargu S, Thamatrakoln K, Kuzminov FI, Twining BS, Marchetti A. Divergent gene expression among phytoplankton taxa in response to upwelling. Environ Microbiol 2018; 20:3069-3082. [DOI: 10.1111/1462-2920.14361] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 06/15/2018] [Accepted: 07/16/2018] [Indexed: 11/29/2022]
Affiliation(s)
- Robert H. Lampe
- Department of Marine Sciences; University of North Carolina at Chapel Hill; Chapel Hill NC USA
| | - Natalie R. Cohen
- Department of Marine Sciences; University of North Carolina at Chapel Hill; Chapel Hill NC USA
| | - Kelsey A. Ellis
- Department of Marine Sciences; University of North Carolina at Chapel Hill; Chapel Hill NC USA
| | - Kenneth W. Bruland
- Department of Ocean Sciences; University of California; Santa Cruz CA USA
| | - Maria T. Maldonado
- Department of Earth, Ocean, and Atmospheric Sciences; University of British Columbia; Vancouver BC Canada
| | - Tawnya D. Peterson
- Institute of Environmental Health, Oregon Health & Science University; Portland OR USA
| | - Claire P. Till
- Department of Ocean Sciences; University of California; Santa Cruz CA USA
- Department of Chemistry; Humboldt State University; Arcata CA USA
| | - Mark A. Brzezinski
- The Marine Science Institute and the Department of Ecology Evolution and Marine Biology; University of California; Santa Barbara CA USA
| | - Sibel Bargu
- Department of Oceanography and Coastal Sciences, School of the Coast and Environment; Louisiana State University; Baton Rouge LA USA
| | - Kimberlee Thamatrakoln
- Department of Marine and Coastal Sciences, Rutgers; the State University of New Jersey; New Brunswick NJ USA
| | - Fedor I Kuzminov
- Department of Marine and Coastal Sciences, Rutgers; the State University of New Jersey; New Brunswick NJ USA
| | | | - Adrian Marchetti
- Department of Marine Sciences; University of North Carolina at Chapel Hill; Chapel Hill NC USA
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88
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Bachy C, Charlesworth CJ, Chan AM, Finke JF, Wong CH, Wei CL, Sudek S, Coleman ML, Suttle CA, Worden AZ. Transcriptional responses of the marine green alga Micromonas pusilla and an infecting prasinovirus under different phosphate conditions. Environ Microbiol 2018; 20:2898-2912. [PMID: 29749714 DOI: 10.1111/1462-2920.14273] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 04/06/2018] [Accepted: 05/07/2018] [Indexed: 12/12/2022]
Abstract
Prasinophytes are widespread marine algae for which responses to nutrient limitation and viral infection are not well understood. We studied the picoprasinophyte, Micromonas pusilla, grown under phosphate-replete (0.65 ± 0.07 d-1 ) and 10-fold lower (low)-phosphate (0.11 ± 0.04 d-1 ) conditions, and infected by the phycodnavirus MpV-SP1. Expression of 17% of Micromonas genes in uninfected cells differed by >1.5-fold (q < 0.01) between nutrient conditions, with genes for P-metabolism and the uniquely-enriched Sel1-like repeat (SLR) family having higher relative transcript abundances, while phospholipid-synthesis genes were lower in low-P than P-replete. Approximately 70% (P-replete) and 30% (low-P) of cells were lysed 24 h post-infection, and expression of ≤5.8% of host genes changed relative to uninfected treatments. Host genes for CAZymes and glycolysis were activated by infection, supporting importance in viral production, which was significantly lower in slower growing (low-P) hosts. All MpV-SP1 genes were expressed, and our analyses suggest responses to differing host-phosphate backgrounds involve few viral genes, while the temporal program of infection involves many more, and is largely independent of host-phosphate background. Our study (i) identifies genes previously unassociated with nutrient acclimation or viral infection, (ii) provides insights into the temporal program of prasinovirus gene expression by hosts and (iii) establishes cell biological aspects of an ecologically important host-prasinovirus system that differ from other marine algal-virus systems.
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Affiliation(s)
- Charles Bachy
- Monterey Bay Aquarium Research Institute, Moss Landing, CA 95039, USA
| | - Christina J Charlesworth
- Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Amy M Chan
- Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Jan F Finke
- Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Chee-Hong Wong
- Lawrence Berkeley National Laboratory, Sequencing Technology Group, Joint Genome Institute, Walnut Creek, CA 94598, USA
| | - Chia-Lin Wei
- Lawrence Berkeley National Laboratory, Sequencing Technology Group, Joint Genome Institute, Walnut Creek, CA 94598, USA
| | - Sebastian Sudek
- Monterey Bay Aquarium Research Institute, Moss Landing, CA 95039, USA
| | - Maureen L Coleman
- Department of the Geophysical Sciences, University of Chicago, Chicago, IL 60637, USA
| | - Curtis A Suttle
- Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.,Integrated Microbial Biodiversity Program, Canadian Institute for Advanced Research, Toronto, M5G 1Z8, Canada.,Departments of Botany, and Microbiology & Immunology, and Institute of Oceans & Fisheries, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Alexandra Z Worden
- Monterey Bay Aquarium Research Institute, Moss Landing, CA 95039, USA.,Integrated Microbial Biodiversity Program, Canadian Institute for Advanced Research, Toronto, M5G 1Z8, Canada
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89
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Okamoto N, Gawryluk RMR, Del Campo J, Strassert JFH, Lukeš J, Richards TA, Worden AZ, Santoro AE, Keeling PJ. A Revised Taxonomy of Diplonemids Including the Eupelagonemidae n. fam. and a Type Species, Eupelagonema oceanica n. gen. & sp. J Eukaryot Microbiol 2018; 66:519-524. [PMID: 30080299 DOI: 10.1111/jeu.12679] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 06/16/2018] [Accepted: 07/12/2018] [Indexed: 12/20/2022]
Abstract
Recent surveys of marine microbial diversity have identified a previously unrecognized lineage of diplonemid protists as being among the most diverse heterotrophic eukaryotes in global oceans. Despite their monophyly (and assumed importance), they lack a formal taxonomic description, and are informally known as deep-sea pelagic diplonemids (DSPDs) or marine diplonemids. Recently, we documented morphology and molecular sequences from several DSPDs, one of which is particularly widespread and abundant in environmental sequence data. To simplify the communication of future work on this important group, here we formally propose to erect the family Eupelagonemidae to encompass this clade, as well as a formal genus and species description for the apparently most abundant phylotype, Eupelagonema oceanica, for which morphological information and single-cell amplified genome data are currently available.
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Affiliation(s)
- Noriko Okamoto
- Department of Botany, University of British Columbia, 3529-6270 University Boulevard, Boulevard, British Columbia, Canada
| | - Ryan M R Gawryluk
- Department of Botany, University of British Columbia, 3529-6270 University Boulevard, Boulevard, British Columbia, Canada
| | - Javier Del Campo
- Department of Botany, University of British Columbia, 3529-6270 University Boulevard, Boulevard, British Columbia, Canada
| | - Jürgen F H Strassert
- Department of Botany, University of British Columbia, 3529-6270 University Boulevard, Boulevard, British Columbia, Canada
| | - Julius Lukeš
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Faculty of Sciences, University of South Bohemia, Branišovská 31, 370 05, České Budějovice (Budweis), Czech Republic
| | - Thomas A Richards
- Biosciences, University of Exeter, Geoffrey Pope Building, Exeter, EX4 4QD, United Kingdom
| | - Alexandra Z Worden
- Monterey Bay Aquarium Research Institute, Moss Landing, California, 95039, USA
| | - Alyson E Santoro
- Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, California, 93106, USA
| | - Patrick J Keeling
- Department of Botany, University of British Columbia, 3529-6270 University Boulevard, Boulevard, British Columbia, Canada
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90
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Waller RF, Cleves PA, Rubio-Brotons M, Woods A, Bender SJ, Edgcomb V, Gann ER, Jones AC, Teytelman L, von Dassow P, Wilhelm SW, Collier JL. Strength in numbers: Collaborative science for new experimental model systems. PLoS Biol 2018; 16:e2006333. [PMID: 29965960 PMCID: PMC6044537 DOI: 10.1371/journal.pbio.2006333] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 07/13/2018] [Indexed: 11/18/2022] Open
Abstract
Our current understanding of biology is heavily based on a small number of genetically tractable model organisms. Most eukaryotic phyla lack such experimental models, and this limits our ability to explore the molecular mechanisms that ultimately define their biology, ecology, and diversity. In particular, marine protists suffer from a paucity of model organisms despite playing critical roles in global nutrient cycles, food webs, and climate. To address this deficit, an initiative was launched in 2015 to foster the development of ecologically and taxonomically diverse marine protist genetic models. The development of new models faces many barriers, some technical and others institutional, and this often discourages the risky, long-term effort that may be required. To lower these barriers and tackle the complexity of this effort, a highly collaborative community-based approach was taken. Herein, we describe this approach, the advances achieved, and the lessons learned by participants in this novel community-based model for research.
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Affiliation(s)
- Ross F. Waller
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
- * E-mail: (RFW); (JLC)
| | - Phillip A. Cleves
- Department of Genetics, Stanford University School of Medicine, Stanford, California, United States of America
| | - Maria Rubio-Brotons
- Institut de Biologia Evolutiva, Spanish National Research Council (CSIC)–Universitat Pompeu Fabra, Barcelona, Catalonia, Spain
| | - April Woods
- Environmental Biotechnology Lab, Moss Landing Marine Laboratories, California, United States of America
| | - Sara J. Bender
- Gordon and Betty Moore Foundation, Palo Alto, California, United States of America
| | - Virginia Edgcomb
- Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts, United States of America
| | - Eric R. Gann
- Department of Microbiology, The University of Tennessee, Knoxville, Tennessee, United States of America
| | - Adam C. Jones
- Gordon and Betty Moore Foundation, Palo Alto, California, United States of America
| | | | - Peter von Dassow
- Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
- Instituto Milenio de Oceanografía, Concepción, Chile
| | - Steven W. Wilhelm
- Department of Microbiology, The University of Tennessee, Knoxville, Tennessee, United States of America
| | - Jackie L. Collier
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, New York, United States of America
- * E-mail: (RFW); (JLC)
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91
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Meng A, Corre E, Probert I, Gutierrez-Rodriguez A, Siano R, Annamale A, Alberti A, Da Silva C, Wincker P, Le Crom S, Not F, Bittner L. Analysis of the genomic basis of functional diversity in dinoflagellates using a transcriptome-based sequence similarity network. Mol Ecol 2018; 27:2365-2380. [PMID: 29624751 DOI: 10.1111/mec.14579] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 02/23/2018] [Accepted: 03/21/2018] [Indexed: 02/06/2023]
Abstract
Dinoflagellates are one of the most abundant and functionally diverse groups of eukaryotes. Despite an overall scarcity of genomic information for dinoflagellates, constantly emerging high-throughput sequencing resources can be used to characterize and compare these organisms. We assembled de novo and processed 46 dinoflagellate transcriptomes and used a sequence similarity network (SSN) to compare the underlying genomic basis of functional features within the group. This approach constitutes the most comprehensive picture to date of the genomic potential of dinoflagellates. A core-predicted proteome composed of 252 connected components (CCs) of putative conserved protein domains (pCDs) was identified. Of these, 206 were novel and 16 lacked any functional annotation in public databases. Integration of functional information in our network analyses allowed investigation of pCDs specifically associated with functional traits. With respect to toxicity, sequences homologous to those of proteins found in species with toxicity potential (e.g., sxtA4 and sxtG) were not specific to known toxin-producing species. Although not fully specific to symbiosis, the most represented functions associated with proteins involved in the symbiotic trait were related to membrane processes and ion transport. Overall, our SSN approach led to identification of 45,207 and 90,794 specific and constitutive pCDs of, respectively, the toxic and symbiotic species represented in our analyses. Of these, 56% and 57%, respectively (i.e., 25,393 and 52,193 pCDs), completely lacked annotation in public databases. This stresses the extent of our lack of knowledge, while emphasizing the potential of SSNs to identify candidate pCDs for further functional genomic characterization.
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Affiliation(s)
- Arnaud Meng
- Sorbonne Universités, UPMC Univ Paris 06, Univ Antilles Guyane, Univ Nice Sophia Antipolis, CNRS, Evolution Paris Seine - Institut de Biologie Paris Seine (EPS - IBPS), Paris, France
| | - Erwan Corre
- CNRS, UPMC, FR2424, ABiMS, Station Biologique, Roscoff, France
| | - Ian Probert
- UPMC-CNRS, FR2424, Roscoff Culture Collection, Station Biologique de Roscoff, Place Georges Teissier, Roscoff, France
| | | | - Raffaele Siano
- Ifremer - Centre de Brest, DYNECO PELAGOS, Plouzané, France
| | - Anita Annamale
- CEA - Institut de Génomique, GENOSCOPE, Evry, France.,CNRS, UMR8030, Evry, France.,Université d'Evry Val d'Essonne, Evry, France
| | - Adriana Alberti
- CEA - Institut de Génomique, GENOSCOPE, Evry, France.,CNRS, UMR8030, Evry, France.,Université d'Evry Val d'Essonne, Evry, France
| | - Corinne Da Silva
- CEA - Institut de Génomique, GENOSCOPE, Evry, France.,CNRS, UMR8030, Evry, France.,Université d'Evry Val d'Essonne, Evry, France
| | - Patrick Wincker
- CEA - Institut de Génomique, GENOSCOPE, Evry, France.,CNRS, UMR8030, Evry, France.,Université d'Evry Val d'Essonne, Evry, France
| | - Stéphane Le Crom
- Sorbonne Universités, UPMC Univ Paris 06, Univ Antilles Guyane, Univ Nice Sophia Antipolis, CNRS, Evolution Paris Seine - Institut de Biologie Paris Seine (EPS - IBPS), Paris, France
| | - Fabrice Not
- CNRS, UMR 7144, Station Biologique de Roscoff, Place Georges Teissier, Roscoff, France
| | - Lucie Bittner
- Sorbonne Universités, UPMC Univ Paris 06, Univ Antilles Guyane, Univ Nice Sophia Antipolis, CNRS, Evolution Paris Seine - Institut de Biologie Paris Seine (EPS - IBPS), Paris, France
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92
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Wang S, Lin Y, Gifford S, Eveleth R, Cassar N. Linking patterns of net community production and marine microbial community structure in the western North Atlantic. THE ISME JOURNAL 2018; 12:2582-2595. [PMID: 29934639 PMCID: PMC6193967 DOI: 10.1038/s41396-018-0163-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 04/03/2018] [Accepted: 05/11/2018] [Indexed: 11/09/2022]
Abstract
Marine net community production (NCP) tracks uptake of carbon by plankton communities and its potential transport to depth. Relationships between marine microbial community composition and NCP currently remain unclear despite their importance for assessing how different taxa impact carbon export. We conducted 16 and 18S rRNA gene (rDNA) sequencing on samples collected across the Western North Atlantic in parallel with high-resolution O2/Ar-derived NCP measurements. Using an internal standard technique to estimate in-situ prokaryotic and eukaryotic rDNA abundances per liter, we employed statistical approaches to relate patterns of microbial diversity to NCP. Taxonomic abundances calculated using internal standards provided valuable context to traditional relative abundance metrics. A bloom in the Mid-Atlantic Bight featured high eukaryote abundances with low eukaryotic diversity and was associated with the harmful algal bloom-forming Aureococcus anophagefferens, phagotrophic algae, heterotrophic flagellates, and particle-associated bacteria. These results show that coastal Aureococcus blooms host a distinct community associated with regionally significant peaks in NCP. Meanwhile, weak relationships between taxonomy and NCP in less-productive waters suggest that productivity across much of this region is not linked to specific microplankton taxa.
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Affiliation(s)
- Seaver Wang
- Division of Earth and Ocean Sciences, Duke University, Durham, USA
| | - Yajuan Lin
- Division of Earth and Ocean Sciences, Duke University, Durham, USA
- Laboratoire des Sciences de l'Environnement Marin (LEMAR), UMR 6539 UBO/CNRS/IRD/IFREMER, Institut Universitaire Européen de la Mer (IUEM), Brest, France
| | - Scott Gifford
- Department of Marine Sciences, the University of North Carolina at Chapel Hill, Chapel Hill, USA
| | - Rachel Eveleth
- Division of Earth and Ocean Sciences, Duke University, Durham, USA
- Department of Environmental Sciences, University of Virginia, Virginia, USA
| | - Nicolas Cassar
- Division of Earth and Ocean Sciences, Duke University, Durham, USA.
- Laboratoire des Sciences de l'Environnement Marin (LEMAR), UMR 6539 UBO/CNRS/IRD/IFREMER, Institut Universitaire Européen de la Mer (IUEM), Brest, France.
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93
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Benoiston AS, Ibarbalz FM, Bittner L, Guidi L, Jahn O, Dutkiewicz S, Bowler C. The evolution of diatoms and their biogeochemical functions. Philos Trans R Soc Lond B Biol Sci 2018; 372:rstb.2016.0397. [PMID: 28717023 DOI: 10.1098/rstb.2016.0397] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/24/2017] [Indexed: 11/12/2022] Open
Abstract
In contemporary oceans diatoms are an important group of eukaryotic phytoplankton that typically dominate in upwelling regions and at high latitudes. They also make significant contributions to sporadic blooms that often occur in springtime. Recent surveys have revealed global information about their abundance and diversity, as well as their contributions to biogeochemical cycles, both as primary producers of organic material and as conduits facilitating the export of carbon and silicon to the ocean interior. Sequencing of diatom genomes is revealing the evolutionary underpinnings of their ecological success by examination of their gene repertoires and the mechanisms they use to adapt to environmental changes. The rise of the diatoms over the last hundred million years is similarly being explored through analysis of microfossils and biomarkers that can be traced through geological time, as well as their contributions to seafloor sediments and fossil fuel reserves. The current review aims to synthesize current information about the evolution and biogeochemical functions of diatoms as they rose to prominence in the global ocean.This article is part of the themed issue 'The peculiar carbon metabolism in diatoms'.
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Affiliation(s)
- Anne-Sophie Benoiston
- Sorbonne Universités, UPMC Univ. Paris 06, Univ. Antilles, Univ. Nice Sophia Antipolis, CNRS, Evolution Paris Seine - Institut de Biologie Paris Seine (EPS - IBPS), 75005 Paris, France
| | - Federico M Ibarbalz
- Ecole Normale Supérieure, PSL Research University, Institut de Biologie de l'Ecole Normale Supérieure (IBENS), CNRS UMR8197, INSERM U1024, 46 rue d'Ulm, 75005 Paris, France
| | - Lucie Bittner
- Sorbonne Universités, UPMC Univ. Paris 06, Univ. Antilles, Univ. Nice Sophia Antipolis, CNRS, Evolution Paris Seine - Institut de Biologie Paris Seine (EPS - IBPS), 75005 Paris, France
| | - Lionel Guidi
- Sorbonne Universités, UPMC Univ. Paris 06, CNRS, Laboratoire d'Océanographie de Villefranche (LOV) UMR7093, Observatoire Océanologique, 06230 Villefranche-sur-Mer, France.,Department of Oceanography, University of Hawaii, Honolulu, HI 96822, USA
| | - Oliver Jahn
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 54-1514 MIT, Cambridge, MA 02139, USA
| | - Stephanie Dutkiewicz
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 54-1514 MIT, Cambridge, MA 02139, USA
| | - Chris Bowler
- Ecole Normale Supérieure, PSL Research University, Institut de Biologie de l'Ecole Normale Supérieure (IBENS), CNRS UMR8197, INSERM U1024, 46 rue d'Ulm, 75005 Paris, France
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94
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Li R, Jiao N, Warren A, Xu D. Changes in community structure of active protistan assemblages from the lower Pearl River to coastal Waters of the South China Sea. Eur J Protistol 2018; 63:72-82. [DOI: 10.1016/j.ejop.2018.01.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 01/12/2018] [Accepted: 01/15/2018] [Indexed: 12/20/2022]
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95
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McQuaid JB, Kustka AB, Oborník M, Horák A, McCrow JP, Karas BJ, Zheng H, Kindeberg T, Andersson AJ, Barbeau KA, Allen AE. Carbonate-sensitive phytotransferrin controls high-affinity iron uptake in diatoms. Nature 2018. [DOI: 10.1038/nature25982] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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96
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Cryptophyta as major bacterivores in freshwater summer plankton. ISME JOURNAL 2018; 12:1668-1681. [PMID: 29463895 PMCID: PMC6018765 DOI: 10.1038/s41396-018-0057-5] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 11/20/2017] [Accepted: 11/28/2017] [Indexed: 01/05/2023]
Abstract
Small bacterivorous eukaryotes play a cardinal role in aquatic food webs and their taxonomic classification is currently a hot topic in aquatic microbial ecology. Despite increasing interest in their diversity, core questions regarding predator–prey specificity remain largely unanswered, e.g., which heterotrophic nanoflagellates (HNFs) are the main bacterivores in freshwaters and which prokaryotes support the growth of small HNFs. To answer these questions, we fed natural communities of HNFs from Římov reservoir (Czech Republic) with five different bacterial strains of the ubiquitous betaproteobacterial genera Polynucleobacter and Limnohabitans. We combined amplicon sequencing and catalyzed reporter deposition fluorescence in situ hybridization (CARD-FISH) targeting eukaryotic 18 S rRNA genes to track specific responses of the natural HNF community to prey amendments. While amplicon sequencing provided valuable qualitative data and a basis for designing specific probes, the number of reads was insufficient to accurately quantify certain eukaryotic groups. We also applied a double-hybridization technique that allows simultaneous phylogenetic identification of both predator and prey. Our results show that community composition of HNFs is strongly dependent upon prey type. Surprisingly, Cryptophyta were the most abundant bacterivores, although this phylum has been so far assumed to be mainly autotrophic. Moreover, the growth of a small lineage of Cryptophyta (CRY1 clade) was strongly stimulated by one Limnohabitans strain in our experiment. Thus, our study is the first report that colorless Cryptophyta are major bacterivores in summer plankton samples and can play a key role in the carbon transfer from prokaryotes to higher trophic levels.
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Burns JA, Pittis AA, Kim E. Gene-based predictive models of trophic modes suggest Asgard archaea are not phagocytotic. Nat Ecol Evol 2018; 2:697-704. [DOI: 10.1038/s41559-018-0477-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 01/11/2018] [Indexed: 12/24/2022]
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Ji N, Lin L, Li L, Yu L, Zhang Y, Luo H, Li M, Shi X, Wang DZ, Lin S. Metatranscriptome analysis reveals environmental and diel regulation of a Heterosigma akashiwo
(raphidophyceae) bloom. Environ Microbiol 2018; 20:1078-1094. [DOI: 10.1111/1462-2920.14045] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 01/09/2018] [Indexed: 11/29/2022]
Affiliation(s)
- Nanjing Ji
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
- Department of Marine Sciences; University of Connecticut; Groton CT 06340 USA
| | - Lingxiao Lin
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
| | - Ling Li
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
| | - Liying Yu
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
| | - Yaqun Zhang
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
| | - Hao Luo
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
| | - Meizhen Li
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
| | - Xinguo Shi
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
| | - Da-Zhi Wang
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
| | - Senjie Lin
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences; Xiamen University; Xiamen Fujian 361102 China
- Department of Marine Sciences; University of Connecticut; Groton CT 06340 USA
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Current Knowledge and Recent Advances in Marine Dinoflagellate Transcriptomic Research. JOURNAL OF MARINE SCIENCE AND ENGINEERING 2018. [DOI: 10.3390/jmse6010013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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