1
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Truchon AR, Chase EE, Stark AR, Wilhelm SW. The diel disconnect between cell growth and division in Aureococcus is interrupted by giant virus infection. Front Microbiol 2024; 15:1426193. [PMID: 39234538 PMCID: PMC11371579 DOI: 10.3389/fmicb.2024.1426193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Accepted: 08/05/2024] [Indexed: 09/06/2024] Open
Abstract
Viruses of eukaryotic algae have become an important research focus due to their role(s) in nutrient cycling and top-down control of algal blooms. Omics-based studies have identified a boon of genomic and transcriptional potential among the Nucleocytoviricota, a phylum of large dsDNA viruses which have been shown to infect algal and non-algal eukaryotes. However, little is still understood regarding the infection cycle of these viruses, particularly in how they take over a metabolically active host and convert it into a virocell state. Of particular interest are the roles light and the diel cycle in virocell development. Yet despite such a large proportion of Nucleocytoviricota infecting phototrophs, little work has been done to tie infection dynamics to the presence, and absence, of light. Here, we examine the role of the diel cycle on the physiological and transcriptional state of the pelagophyte Aureococcus anophagefferens while undergoing infection by Kratosvirus quantuckense strain AaV. Our observations demonstrate how infection by the virus interrupts the diel growth and division of this cell strain, and that infection further complicates the system by enhancing export of cell biomass.
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Affiliation(s)
- Alexander R Truchon
- Department of Microbiology, University of Tennessee, Knoxville, TN, United States
| | - Emily E Chase
- Department of Microbiology, University of Tennessee, Knoxville, TN, United States
| | - Ashton R Stark
- Department of Microbiology, University of Tennessee, Knoxville, TN, United States
| | - Steven W Wilhelm
- Department of Microbiology, University of Tennessee, Knoxville, TN, United States
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2
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Edwards BR, Thamatrakoln K, Fredricks HF, Bidle KD, Van Mooy BAS. Viral Infection Leads to a Unique Suite of Allelopathic Chemical Signals in Three Diatom Host-Virus Pairs. Mar Drugs 2024; 22:228. [PMID: 38786618 PMCID: PMC11123003 DOI: 10.3390/md22050228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Revised: 04/27/2024] [Accepted: 05/02/2024] [Indexed: 05/25/2024] Open
Abstract
Ecophysiological stress and the grazing of diatoms are known to elicit the production of chemical defense compounds called oxylipins, which are toxic to a wide range of marine organisms. Here we show that (1) the viral infection and lysis of diatoms resulted in oxylipin production; (2) the suite of compounds produced depended on the diatom host and the infecting virus; and (3) the virus-mediated oxylipidome was distinct, in both magnitude and diversity, from oxylipins produced due to stress associated with the growth phase. We used high-resolution accurate-mass mass spectrometry to observe changes in the dissolved lipidome of diatom cells infected with viruses over 3 to 4 days, compared to diatom cells in exponential, stationary, and decline phases of growth. Three host virus pairs were used as model systems: Chaetoceros tenuissimus infected with CtenDNAV; C. tenuissimus infected with CtenRNAV; and Chaetoceros socialis infected with CsfrRNAV. Several of the compounds that were significantly overproduced during viral infection are known to decrease the reproductive success of copepods and interfere with microzooplankton grazing. Specifically, oxylipins associated with allelopathy towards zooplankton from the 6-, 9-, 11-, and 15-lipogenase (LOX) pathways were significantly more abundant during viral lysis. 9-hydroperoxy hexadecatetraenoic acid was identified as the strongest biomarker for the infection of Chaetoceros diatoms. C. tenuissimus produced longer, more oxidized oxylipins when lysed by CtenRNAV compared to CtenDNAV. However, CtenDNAV caused a more statistically significant response in the lipidome, producing more oxylipins from known diatom LOX pathways than CtenRNAV. A smaller set of compounds was significantly more abundant in stationary and declining C. tenuissimus and C. socialis controls. Two allelopathic oxylipins in the 15-LOX pathway and essential fatty acids, arachidonic acid (ARA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) were more abundant in the stationary phase than during the lysis of C. socialis. The host-virus pair comparisons underscore the species-level differences in oxylipin production and the value of screening more host-virus systems. We propose that the viral infection of diatoms elicits chemical defense via oxylipins which deters grazing with downstream trophic and biogeochemical effects.
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Affiliation(s)
- Bethanie R. Edwards
- Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Falmouth, MA 02543, USA; (H.F.F.); (B.A.S.V.M.)
- Department of Earth and Planetary Science, University of California-Berkeley, Berkeley, CA 94720, USA
| | - Kimberlee Thamatrakoln
- Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, NJ 08901, USA; (K.T.); (K.D.B.)
| | - Helen F. Fredricks
- Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Falmouth, MA 02543, USA; (H.F.F.); (B.A.S.V.M.)
| | - Kay D. Bidle
- Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, NJ 08901, USA; (K.T.); (K.D.B.)
| | - Benjamin A. S. Van Mooy
- Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Falmouth, MA 02543, USA; (H.F.F.); (B.A.S.V.M.)
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3
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Zheng S, Lee V, Meza-Padilla I, Nissimov JI. Antiviral discovery in toxic cyanobacteria: Low hanging fruit in the age of pandemics. JOURNAL OF PHYCOLOGY 2024; 60:574-580. [PMID: 38174634 DOI: 10.1111/jpy.13425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 09/15/2023] [Accepted: 12/12/2023] [Indexed: 01/05/2024]
Abstract
The power of novel vaccination technologies and their rapid development were elucidated clearly during the COVID-19 pandemic. At the same time, it also became clear that there is an urgent need to discover and manufacture new antivirals that target emerging viral threats. Toxic species of cyanobacteria produce a range of bioactive compounds that makes them good candidates for drug discovery. Nevertheless, few studies demonstrate the antiviral potential of cyanobacteria. This is partly due to the lack of specific and simple protocols designed for the rapid detection of antiviral activity in cyanobacteria and partly because specialized facilities for work with pathogenic viruses are few and far between. We therefore developed an easy method for the screening of cyanobacterial cultures for antiviral activity and used our private culture collection of non-pathogenic virus isolates to show that antiviral activity is a prominent feature in the cyanobacterium Microcystis aeruginosa. In this proof-of-concept study, we show that M. aeruginosa extracts from three different cyanobacterial strains delay infection of diatom-infecting single-stranded DNA and single-stranded RNA viruses by up to 2 days. Our work shows the ease with which cyanobacteria from culture collections can be screened for antiviral activity and highlights the potential of cyanobacteria as an excellent source for the discovery of novel antiviral compounds, warranting further investigation.
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Affiliation(s)
- Sally Zheng
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada
| | - Victoria Lee
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada
| | - Isaac Meza-Padilla
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada
| | - Jozef I Nissimov
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada
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4
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Queiroz VF, Tatara JM, Botelho BB, Rodrigues RAL, Almeida GMDF, Abrahao JS. The consequences of viral infection on protists. Commun Biol 2024; 7:306. [PMID: 38462656 PMCID: PMC10925606 DOI: 10.1038/s42003-024-06001-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Accepted: 02/29/2024] [Indexed: 03/12/2024] Open
Abstract
Protists encompass a vast widely distributed group of organisms, surpassing the diversity observed in metazoans. Their diverse ecological niches and life forms are intriguing characteristics that render them valuable subjects for in-depth cell biology studies. Throughout history, viruses have played a pivotal role in elucidating complex cellular processes, particularly in the context of cellular responses to viral infections. In this comprehensive review, we provide an overview of the cellular alterations that are triggered in specific hosts following different viral infections and explore intricate biological interactions observed in experimental conditions using different host-pathogen groups.
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Affiliation(s)
- Victoria Fulgencio Queiroz
- Federal University of Minas Gerais, Institute of Biological Sciences, Department of Microbiology, Belo Horizonte, Minas Gerais, Brazil
| | - Juliana Miranda Tatara
- The Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, UiT - The Arctic University of Norway, Tromsø, Norway
| | - Bruna Barbosa Botelho
- Federal University of Minas Gerais, Institute of Biological Sciences, Department of Microbiology, Belo Horizonte, Minas Gerais, Brazil
| | - Rodrigo Araújo Lima Rodrigues
- Federal University of Minas Gerais, Institute of Biological Sciences, Department of Microbiology, Belo Horizonte, Minas Gerais, Brazil
| | - Gabriel Magno de Freitas Almeida
- The Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, UiT - The Arctic University of Norway, Tromsø, Norway.
| | - Jonatas Santos Abrahao
- Federal University of Minas Gerais, Institute of Biological Sciences, Department of Microbiology, Belo Horizonte, Minas Gerais, Brazil
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5
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Carella F, Prado P, De Vico G, Palić D, Villari G, García-March JR, Tena-Medialdea J, Cortés Melendreras E, Giménez-Casalduero F, Sigovini M, Aceto S. A widespread picornavirus affects the hemocytes of the noble pen shell ( Pinna nobilis), leading to its immunosuppression. Front Vet Sci 2023; 10:1273521. [PMID: 38164394 PMCID: PMC10758234 DOI: 10.3389/fvets.2023.1273521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Accepted: 11/13/2023] [Indexed: 01/03/2024] Open
Abstract
Introduction The widespread mass mortality of the noble pen shell (Pinna nobilis) has occurred in several Mediterranean countries in the past 7 years. Single-stranded RNA viruses affecting immune cells and leading to immune dysfunction have been widely reported in human and animal species. Here, we present data linking P. nobilis mass mortality events (MMEs) to hemocyte picornavirus (PV) infection. This study was performed on specimens from wild and captive populations. Methods We sampled P. nobilis from two regions of Spain [Catalonia (24 animals) and Murcia (four animals)] and one region in Italy [Venice (6 animals)]. Each of them were analyzed using transmission electron microscopy (TEM) to describe the morphology and self-assembly of virions. Illumina sequencing coupled to qPCR was performed to describe the identified virus and part of its genome. Results and discussion In 100% of our samples, ultrastructure revealed the presence of a virus (20 nm diameter) capable of replicating within granulocytes and hyalinocytes, leading to the accumulation of complex vesicles of different dimensions within the cytoplasm. As the PV infection progressed, dead hemocytes, infectious exosomes, and budding of extracellular vesicles were visible, along with endocytic vesicles entering other cells. The THC (total hemocyte count) values observed in both captive (eight animals) (3.5 × 104-1.60 × 105 ml-1 cells) and wild animals (14 samples) (1.90-2.42 × 105 ml-1 cells) were lower than those reported before MMEs. Sequencing of P. nobilis (six animals) hemocyte cDNA libraries revealed the presence of two main sequences of Picornavirales, family Marnaviridae. The highest number of reads belonged to animals that exhibited active replication phases and abundant viral particles from transmission electron microscopy (TEM) observations. These sequences correspond to the genus Sogarnavirus-a picornavirus identified in the marine diatom Chaetoceros tenuissimus (named C. tenuissimus RNA virus type II). Real-time PCR performed on the two most abundant RNA viruses previously identified by in silico analysis revealed positive results only for sequences similar to the C. tenuissimus RNA virus. These results may not conclusively identify picornavirus in noble pen shell hemocytes; therefore, further study is required. Our findings suggest that picornavirus infection likely causes immunosuppression, making individuals prone to opportunistic infections, which is a potential cause for the MMEs observed in the Mediterranean.
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Affiliation(s)
- Francesca Carella
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Patricia Prado
- Institute of Agrifood Research and Technology (IRTA)-Sant Carles de la Ràpita, Tarragona, Spain
| | - Gionata De Vico
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Dušan Palić
- Chair for Fish Diseases and Fisheries Biology, Faculty of Veterinary Medicine, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Grazia Villari
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - José Rafael García-March
- Instituto de Investigación en Medio Ambiente y Ciencia Marina, Universidad Católica de Valencia, Calpe, Spain
| | - José Tena-Medialdea
- Instituto de Investigación en Medio Ambiente y Ciencia Marina, Universidad Católica de Valencia, Calpe, Spain
| | | | - Francisca Giménez-Casalduero
- Department of Marine Science and Applied Biology, Research Marine Centre in Santa Pola (CIMAR), University of Alicante, Alicante, Spain
| | - Marco Sigovini
- Consiglio Nazionale delle Ricerche, Istituto di Scienze Marine, Venice, Italy
| | - Serena Aceto
- Department of Biology, University of Naples Federico II, Naples, Italy
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6
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Potapov S, Gorshkova A, Krasnopeev A, Podlesnaya G, Tikhonova I, Suslova M, Kwon D, Patrushev M, Drucker V, Belykh O. RNA-Seq Virus Fraction in Lake Baikal and Treated Wastewaters. Int J Mol Sci 2023; 24:12049. [PMID: 37569424 PMCID: PMC10418309 DOI: 10.3390/ijms241512049] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 07/17/2023] [Accepted: 07/19/2023] [Indexed: 08/13/2023] Open
Abstract
In this study, we analyzed the transcriptomes of RNA and DNA viruses from the oligotrophic water of Lake Baikal and the effluent from wastewater treatment plants (WWTPs) discharged into the lake from the towns of Severobaikalsk and Slyudyanka located on the lake shores. Given the uniqueness and importance of Lake Baikal, the issues of biodiversity conservation and the monitoring of potential virological hazards to hydrobionts and humans are important. Wastewater treatment plants discharge treated effluent directly into the lake. In this context, the identification and monitoring of allochthonous microorganisms entering the lake play an important role. Using high-throughput sequencing methods, we found that dsDNA-containing viruses of the class Caudoviricetes were the most abundant in all samples, while Leviviricetes (ssRNA(+) viruses) dominated the treated water samples. RNA viruses of the families Nodaviridae, Tombusviridae, Dicitroviridae, Picobirnaviridae, Botourmiaviridae, Marnaviridae, Solemoviridae, and Endornavirida were found in the pelagic zone of three lake basins. Complete or nearly complete genomes of RNA viruses belonging to such families as Dicistroviridae, Marnaviridae, Blumeviridae, Virgaviridae, Solspiviridae, Nodaviridae, and Fiersviridae and the unassigned genus Chimpavirus, as well as unclassified picorna-like viruses, were identified. In general, the data of sanitary/microbiological and genetic analyses showed that WWTPs inadequately purify the discharged water, but, at the same time, we did not observe viruses pathogenic to humans in the pelagic zone of the lake.
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Affiliation(s)
- Sergey Potapov
- Limnological Institute, Siberian Branch of the Russian Academy of Sciences, Ulan-Batorskaya 3, 664033 Irkutsk, Russia (O.B.)
| | - Anna Gorshkova
- Limnological Institute, Siberian Branch of the Russian Academy of Sciences, Ulan-Batorskaya 3, 664033 Irkutsk, Russia (O.B.)
| | - Andrey Krasnopeev
- Limnological Institute, Siberian Branch of the Russian Academy of Sciences, Ulan-Batorskaya 3, 664033 Irkutsk, Russia (O.B.)
| | - Galina Podlesnaya
- Limnological Institute, Siberian Branch of the Russian Academy of Sciences, Ulan-Batorskaya 3, 664033 Irkutsk, Russia (O.B.)
| | - Irina Tikhonova
- Limnological Institute, Siberian Branch of the Russian Academy of Sciences, Ulan-Batorskaya 3, 664033 Irkutsk, Russia (O.B.)
| | - Maria Suslova
- Limnological Institute, Siberian Branch of the Russian Academy of Sciences, Ulan-Batorskaya 3, 664033 Irkutsk, Russia (O.B.)
| | - Dmitry Kwon
- National Research Center Kurchatov Institute, Academician Kurchatov Square 1, 123098 Moscow, Russia
| | - Maxim Patrushev
- National Research Center Kurchatov Institute, Academician Kurchatov Square 1, 123098 Moscow, Russia
| | - Valentin Drucker
- Limnological Institute, Siberian Branch of the Russian Academy of Sciences, Ulan-Batorskaya 3, 664033 Irkutsk, Russia (O.B.)
| | - Olga Belykh
- Limnological Institute, Siberian Branch of the Russian Academy of Sciences, Ulan-Batorskaya 3, 664033 Irkutsk, Russia (O.B.)
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7
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Diaz BP, Gallo F, Moore RH, Bidle KD. Virus infection of phytoplankton increases average molar mass and reduces hygroscopicity of aerosolized organic matter. Sci Rep 2023; 13:7361. [PMID: 37147322 PMCID: PMC10163044 DOI: 10.1038/s41598-023-33818-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Accepted: 04/19/2023] [Indexed: 05/07/2023] Open
Abstract
Viral infection of phytoplankton is a pervasive mechanism of cell death and bloom termination, which leads to the production of dissolved and colloidal organic matter that can be aerosolized into the atmosphere. Earth-observing satellites can track the growth and death of phytoplankton blooms on weekly time scales but the impact of viral infection on the cloud forming potential of associated aerosols is largely unknown. Here, we determine the influence of viral-derived organic matter, purified viruses, and marine hydrogels on the cloud condensation nuclei activity of their aerosolized solutions, compared to organic exudates from healthy phytoplankton. Dissolved organic material derived from exponentially growing and infected cells of well-characterized eukaryotic phytoplankton host-virus systems, including viruses from diatoms, coccolithophores and chlorophytes, was concentrated, desalted, and nebulized to form aerosol particles composed of primarily of organic matter. Aerosols from infected phytoplankton cultures resulted in an increase in critical activation diameter and average molar mass in three out of five combinations evaluated, along with a decrease in organic kappa (hygroscopicity) compared to healthy cultures and seawater controls. The infected samples also displayed evidence of increased surface tension depression at realistic cloud water vapor supersaturations. Amending the samples with xanthan gum to simulate marine hydrogels increased variability in organic kappa and surface tension in aerosols with high organic to salt ratios. Our findings suggest that the pulses of increased dissolved organic matter associated with viral infection in surface waters may increase the molar mass of dissolved organic compounds relative to surface waters occupied by healthy phytoplankton or low phytoplankton biomass.
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Affiliation(s)
- Ben P Diaz
- Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, USA
| | - Francesca Gallo
- NASA Langley Research Center, Hampton, VA, USA
- NASA Postdoctoral Program, Oak Ridge Associated Universities, Oak Ridge, TN, USA
| | | | - Kay D Bidle
- Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, USA.
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8
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Dominguez‐Huerta G, Wainaina JM, Zayed AA, Culley AI, Kuhn JH, Sullivan MB. The RNA virosphere: How big and diverse is it? Environ Microbiol 2023; 25:209-215. [PMID: 36511833 PMCID: PMC9852017 DOI: 10.1111/1462-2920.16312] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 12/10/2022] [Indexed: 12/15/2022]
Affiliation(s)
- Guillermo Dominguez‐Huerta
- Department of MicrobiologyOhio State UniversityColumbusOhioUSA
- Center of Microbiome ScienceOhio State UniversityColumbusOhioUSA
| | - James M. Wainaina
- Department of MicrobiologyOhio State UniversityColumbusOhioUSA
- Center of Microbiome ScienceOhio State UniversityColumbusOhioUSA
| | - Ahmed A. Zayed
- Department of MicrobiologyOhio State UniversityColumbusOhioUSA
- Center of Microbiome ScienceOhio State UniversityColumbusOhioUSA
| | - Alexander I. Culley
- Pacific Biosciences Research CenterUniversity of Hawai'i at MānoaHonoluluHawaiiUSA
| | - Jens H. Kuhn
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious DiseasesNational Institutes of HealthFrederickMarylandUSA
| | - Matthew B. Sullivan
- Department of MicrobiologyOhio State UniversityColumbusOhioUSA
- Center of Microbiome ScienceOhio State UniversityColumbusOhioUSA
- Department of Civil, Environmental and Geodetic EngineeringOhio State UniversityColumbusOhioUSA
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9
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Wang H, Munke A, Li S, Tomaru Y, Okamoto K. Structural Insights into Common and Host-Specific Receptor-Binding Mechanisms in Algal Picorna-like Viruses. Viruses 2022; 14:2369. [PMID: 36366467 PMCID: PMC9697754 DOI: 10.3390/v14112369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 10/17/2022] [Accepted: 10/19/2022] [Indexed: 01/31/2023] Open
Abstract
Marnaviridae viruses are abundant algal viruses that regulate the dynamics of algal blooms in aquatic environments. They employ a narrow host range because they merely lyse their algal host species. This host-specific lysis is thought to correspond to the unique receptor-binding mechanism of the Marnaviridae viruses. Here, we present the atomic structures of the full and empty capsids of Chaetoceros socialis forma radians RNA virus 1 built-in 3.0 Å and 3.1 Å cryo-electron microscopy maps. The empty capsid structure and the structural variability provide insights into its assembly and uncoating intermediates. In conjunction with the previously reported atomic model of the Chaetoceros tenuissimus RNA virus type II capsid, we have identified the common and diverse structural features of the VP1 surface between the Marnaviridae viruses. We have also tested the potential usage of AlphaFold2 for structural prediction of the VP1s and a subsequent structural phylogeny for classifying Marnaviridae viruses by their hosts. These findings will be crucial for inferring the host-specific receptor-binding mechanism in Marnaviridae viruses.
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Affiliation(s)
- Han Wang
- The Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, 75124 Uppsala, Sweden
| | - Anna Munke
- The Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, 75124 Uppsala, Sweden
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | - Siqi Li
- The Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, 75124 Uppsala, Sweden
| | - Yuji Tomaru
- Fisheries Technology Institute, Japan Fisheries Research and Education Agency, Hatsukaichi 739-0452, Hiroshima, Japan
| | - Kenta Okamoto
- The Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, 75124 Uppsala, Sweden
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10
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Dominguez-Huerta G, Zayed AA, Wainaina JM, Guo J, Tian F, Pratama AA, Bolduc B, Mohssen M, Zablocki O, Pelletier E, Delage E, Alberti A, Aury JM, Carradec Q, da Silva C, Labadie K, Poulain J, Bowler C, Eveillard D, Guidi L, Karsenti E, Kuhn JH, Ogata H, Wincker P, Culley A, Chaffron S, Sullivan MB. Diversity and ecological footprint of Global Ocean RNA viruses. Science 2022; 376:1202-1208. [PMID: 35679415 DOI: 10.1126/science.abn6358] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
DNA viruses are increasingly recognized as influencing marine microbes and microbe-mediated biogeochemical cycling. However, little is known about global marine RNA virus diversity, ecology, and ecosystem roles. In this study, we uncover patterns and predictors of marine RNA virus community- and "species"-level diversity and contextualize their ecological impacts from pole to pole. Our analyses revealed four ecological zones, latitudinal and depth diversity patterns, and environmental correlates for RNA viruses. Our findings only partially parallel those of cosampled plankton and show unexpectedly high polar ecological interactions. The influence of RNA viruses on ecosystems appears to be large, as predicted hosts are ecologically important. Moreover, the occurrence of auxiliary metabolic genes indicates that RNA viruses cause reprogramming of diverse host metabolisms, including photosynthesis and carbon cycling, and that RNA virus abundances predict ocean carbon export.
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Affiliation(s)
- Guillermo Dominguez-Huerta
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA.,EMERGE Biology Integration Institute, The Ohio State University, Columbus, OH 43210, USA.,Center of Microbiome Science, The Ohio State University, Columbus, OH 43210, USA
| | - Ahmed A Zayed
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA.,EMERGE Biology Integration Institute, The Ohio State University, Columbus, OH 43210, USA.,Center of Microbiome Science, The Ohio State University, Columbus, OH 43210, USA
| | - James M Wainaina
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA.,Center of Microbiome Science, The Ohio State University, Columbus, OH 43210, USA
| | - Jiarong Guo
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA.,EMERGE Biology Integration Institute, The Ohio State University, Columbus, OH 43210, USA.,Center of Microbiome Science, The Ohio State University, Columbus, OH 43210, USA
| | - Funing Tian
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA.,Center of Microbiome Science, The Ohio State University, Columbus, OH 43210, USA
| | - Akbar Adjie Pratama
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA.,EMERGE Biology Integration Institute, The Ohio State University, Columbus, OH 43210, USA
| | - Benjamin Bolduc
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA.,EMERGE Biology Integration Institute, The Ohio State University, Columbus, OH 43210, USA.,Center of Microbiome Science, The Ohio State University, Columbus, OH 43210, USA
| | - Mohamed Mohssen
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA.,Center of Microbiome Science, The Ohio State University, Columbus, OH 43210, USA.,The Interdisciplinary Biophysics Graduate Program, The Ohio State University, Columbus, Ohio 43210, USA
| | - Olivier Zablocki
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA.,EMERGE Biology Integration Institute, The Ohio State University, Columbus, OH 43210, USA.,Center of Microbiome Science, The Ohio State University, Columbus, OH 43210, USA
| | - Eric Pelletier
- Génomique Métabolique, Genoscope, Institut François-Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, 91000 Evry, France.,Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
| | - Erwan Delage
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France.,Nantes Université, École Centrale Nantes, CNRS, LS2N, UMR 6004, F-44000 Nantes, France
| | - Adriana Alberti
- Génomique Métabolique, Genoscope, Institut François-Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, 91000 Evry, France.,Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
| | - Jean-Marc Aury
- Génomique Métabolique, Genoscope, Institut François-Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, 91000 Evry, France
| | - Quentin Carradec
- Génomique Métabolique, Genoscope, Institut François-Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, 91000 Evry, France.,Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
| | - Corinne da Silva
- Génomique Métabolique, Genoscope, Institut François-Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, 91000 Evry, France
| | - Karine Labadie
- Génomique Métabolique, Genoscope, Institut François-Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, 91000 Evry, France.,Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
| | - Julie Poulain
- Génomique Métabolique, Genoscope, Institut François-Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, 91000 Evry, France.,Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
| | | | - Chris Bowler
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France.,Institut de Biologie de l'Ecole Normale Supérieure, Ecole Normale Supérieure, CNRS, INSERM, Université PSL, 75005 Paris, France
| | - Damien Eveillard
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France.,Nantes Université, École Centrale Nantes, CNRS, LS2N, UMR 6004, F-44000 Nantes, France
| | - Lionel Guidi
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France.,Sorbonne Université, CNRS, Laboratoire d'Océanographie de Villefanche, LOV, F-06230 Villefranche-sur-mer, France
| | - Eric Karsenti
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France.,Institut de Biologie de l'Ecole Normale Supérieure, Ecole Normale Supérieure, CNRS, INSERM, Université PSL, 75005 Paris, France.,Directors' Research European Molecular Biology Laboratory, 69117 Heidelberg, Germany
| | - Jens H Kuhn
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, MD 21702, USA
| | - Hiroyuki Ogata
- Institute for Chemical Research, Kyoto University, Kyoto 611-0011, Japan
| | - Patrick Wincker
- Génomique Métabolique, Genoscope, Institut François-Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, 91000 Evry, France.,Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
| | - Alexander Culley
- Département de Biochimie, Microbiologie et Bio-informatique, Université Laval, Québec, QC G1V 0A6, Canada
| | - Samuel Chaffron
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France.,Nantes Université, École Centrale Nantes, CNRS, LS2N, UMR 6004, F-44000 Nantes, France
| | - Matthew B Sullivan
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA.,EMERGE Biology Integration Institute, The Ohio State University, Columbus, OH 43210, USA.,Center of Microbiome Science, The Ohio State University, Columbus, OH 43210, USA.,The Interdisciplinary Biophysics Graduate Program, The Ohio State University, Columbus, Ohio 43210, USA.,Department of Civil, Environmental and Geodetic Engineering, The Ohio State University, Columbus, OH 43210, USA
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11
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Zayed AA, Wainaina JM, Dominguez-Huerta G, Pelletier E, Guo J, Mohssen M, Tian F, Pratama AA, Bolduc B, Zablocki O, Cronin D, Solden L, Delage E, Alberti A, Aury JM, Carradec Q, da Silva C, Labadie K, Poulain J, Ruscheweyh HJ, Salazar G, Shatoff E, Coordinators TO, Bundschuh R, Fredrick K, Kubatko LS, Chaffron S, Culley AI, Sunagawa S, Kuhn JH, Wincker P, Sullivan MB. Cryptic and abundant marine viruses at the evolutionary origins of Earth's RNA virome. Science 2022; 376:156-162. [PMID: 35389782 PMCID: PMC10990476 DOI: 10.1126/science.abm5847] [Citation(s) in RCA: 104] [Impact Index Per Article: 52.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Whereas DNA viruses are known to be abundant, diverse, and commonly key ecosystem players, RNA viruses are insufficiently studied outside disease settings. In this study, we analyzed ≈28 terabases of Global Ocean RNA sequences to expand Earth's RNA virus catalogs and their taxonomy, investigate their evolutionary origins, and assess their marine biogeography from pole to pole. Using new approaches to optimize discovery and classification, we identified RNA viruses that necessitate substantive revisions of taxonomy (doubling phyla and adding >50% new classes) and evolutionary understanding. "Species"-rank abundance determination revealed that viruses of the new phyla "Taraviricota," a missing link in early RNA virus evolution, and "Arctiviricota" are widespread and dominant in the oceans. These efforts provide foundational knowledge critical to integrating RNA viruses into ecological and epidemiological models.
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Affiliation(s)
- Ahmed A. Zayed
- Department of Microbiology, Ohio State University, Columbus, OH 43210, USA
- EMERGE Biology Integration Institute, Ohio State University, Columbus, OH 43210, USA
- Center of Microbiome Science, Ohio State University, Columbus, OH 43210, USA
| | - James M. Wainaina
- Department of Microbiology, Ohio State University, Columbus, OH 43210, USA
- Center of Microbiome Science, Ohio State University, Columbus, OH 43210, USA
| | - Guillermo Dominguez-Huerta
- Department of Microbiology, Ohio State University, Columbus, OH 43210, USA
- EMERGE Biology Integration Institute, Ohio State University, Columbus, OH 43210, USA
- Center of Microbiome Science, Ohio State University, Columbus, OH 43210, USA
| | - Eric Pelletier
- Génomique Métabolique, Genoscope, Institut François-Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, 91000 Evry, France
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
| | - Jiarong Guo
- Department of Microbiology, Ohio State University, Columbus, OH 43210, USA
- EMERGE Biology Integration Institute, Ohio State University, Columbus, OH 43210, USA
- Center of Microbiome Science, Ohio State University, Columbus, OH 43210, USA
| | - Mohamed Mohssen
- Department of Microbiology, Ohio State University, Columbus, OH 43210, USA
- Center of Microbiome Science, Ohio State University, Columbus, OH 43210, USA
- The Interdisciplinary Biophysics Graduate Program, Ohio State University, Columbus, OH 43210, USA
| | - Funing Tian
- Department of Microbiology, Ohio State University, Columbus, OH 43210, USA
- Center of Microbiome Science, Ohio State University, Columbus, OH 43210, USA
| | - Akbar Adjie Pratama
- Department of Microbiology, Ohio State University, Columbus, OH 43210, USA
- EMERGE Biology Integration Institute, Ohio State University, Columbus, OH 43210, USA
| | - Benjamin Bolduc
- Department of Microbiology, Ohio State University, Columbus, OH 43210, USA
- EMERGE Biology Integration Institute, Ohio State University, Columbus, OH 43210, USA
- Center of Microbiome Science, Ohio State University, Columbus, OH 43210, USA
| | - Olivier Zablocki
- Department of Microbiology, Ohio State University, Columbus, OH 43210, USA
- EMERGE Biology Integration Institute, Ohio State University, Columbus, OH 43210, USA
- Center of Microbiome Science, Ohio State University, Columbus, OH 43210, USA
| | - Dylan Cronin
- Department of Microbiology, Ohio State University, Columbus, OH 43210, USA
- EMERGE Biology Integration Institute, Ohio State University, Columbus, OH 43210, USA
- Center of Microbiome Science, Ohio State University, Columbus, OH 43210, USA
| | - Lindsey Solden
- Department of Microbiology, Ohio State University, Columbus, OH 43210, USA
| | - Erwan Delage
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
- Nantes Université, CNRS UMR 6004, LS2N, F-44000 Nantes, France
| | - Adriana Alberti
- Génomique Métabolique, Genoscope, Institut François-Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, 91000 Evry, France
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
| | - Jean-Marc Aury
- Génomique Métabolique, Genoscope, Institut François-Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, 91000 Evry, France
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
| | - Quentin Carradec
- Génomique Métabolique, Genoscope, Institut François-Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, 91000 Evry, France
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
| | - Corinne da Silva
- Génomique Métabolique, Genoscope, Institut François-Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, 91000 Evry, France
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
| | - Karine Labadie
- Génomique Métabolique, Genoscope, Institut François-Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, 91000 Evry, France
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
| | - Julie Poulain
- Génomique Métabolique, Genoscope, Institut François-Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, 91000 Evry, France
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
| | - Hans-Joachim Ruscheweyh
- Department of Biology, Institute of Microbiology and Swiss Institute of Bioinformatics, ETH Zurich, Zurich, Switzerland
| | - Guillem Salazar
- Department of Biology, Institute of Microbiology and Swiss Institute of Bioinformatics, ETH Zurich, Zurich, Switzerland
| | - Elan Shatoff
- Department of Physics, Ohio State University, Columbus, OH 43210, USA
| | | | - Ralf Bundschuh
- The Interdisciplinary Biophysics Graduate Program, Ohio State University, Columbus, OH 43210, USA
- Department of Physics, Ohio State University, Columbus, OH 43210, USA
- Department of Chemistry and Biochemistry, Ohio State University, Columbus, OH 43210, USA
- Division of Hematology, Department of Internal Medicine, Ohio State University, Columbus, OH 43210, USA
| | - Kurt Fredrick
- Department of Microbiology, Ohio State University, Columbus, OH 43210, USA
| | - Laura S. Kubatko
- Department of Evolution, Ecology, and Organismal Biology, Ohio State University, Columbus, OH 43210, USA
- Department of Statistics, Ohio State University, Columbus, OH 43210, USA
| | - Samuel Chaffron
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
- Nantes Université, CNRS UMR 6004, LS2N, F-44000 Nantes, France
| | - Alexander I. Culley
- Département de Biochimie, Microbiologie et Bio-informatique, Université Laval, Québec, Québec G1V 0A6, Canada
| | - Shinichi Sunagawa
- Department of Biology, Institute of Microbiology and Swiss Institute of Bioinformatics, ETH Zurich, Zurich, Switzerland
| | - Jens H. Kuhn
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, MD 21702, USA
| | - Patrick Wincker
- Génomique Métabolique, Genoscope, Institut François-Jacob, CEA, CNRS, Univ Evry, Université Paris-Saclay, 91000 Evry, France
- Research Federation for the Study of Global Ocean Systems Ecology and Evolution, FR2022/Tara Oceans GOSEE, 75016 Paris, France
| | - Matthew B. Sullivan
- Department of Microbiology, Ohio State University, Columbus, OH 43210, USA
- EMERGE Biology Integration Institute, Ohio State University, Columbus, OH 43210, USA
- Center of Microbiome Science, Ohio State University, Columbus, OH 43210, USA
- The Interdisciplinary Biophysics Graduate Program, Ohio State University, Columbus, OH 43210, USA
- Department of Evolution, Ecology, and Organismal Biology, Ohio State University, Columbus, OH 43210, USA
- Department of Civil, Environmental, and Geodetic Engineering, Ohio State University, Columbus, OH 43210, USA
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12
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Marine viruses and climate change: Virioplankton, the carbon cycle, and our future ocean. Adv Virus Res 2022. [DOI: 10.1016/bs.aivir.2022.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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13
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Chase EE, Monteil-Bouchard S, Gobet A, Andrianjakarivony FH, Desnues C, Blanc G. A High Rate Algal Pond Hosting a Dynamic Community of RNA Viruses. Viruses 2021; 13:2163. [PMID: 34834969 PMCID: PMC8619904 DOI: 10.3390/v13112163] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 10/19/2021] [Accepted: 10/22/2021] [Indexed: 12/16/2022] Open
Abstract
Despite a surge of RNA virome sequencing in recent years, there are still many RNA viruses to uncover-as indicated by the relevance of viral dark matter to RNA virome studies (i.e., putative viruses that do not match to taxonomically identified viruses). This study explores a unique site, a high-rate algal pond (HRAP), for culturing industrially microalgae, to elucidate new RNA viruses. The importance of viral-host interactions in aquatic systems are well documented, and the ever-expanding microalgae industry is no exception. As the industry becomes a more important source of sustainable plastic manufacturing, a producer of cosmetic pigments and alternative protein sources, and a means of CO2 remediation in the face of climate change, studying microalgal viruses becomes a vital practice for proactive management of microalgae cultures at the industrial level. This study provides evidence of RNA microalgal viruses persisting in a CO2 remediation pilot project HRAP and uncovers the diversity of the RNA virosphere contained within it. Evidence shows that family Marnaviridae is cultured in the basin, alongside other potential microalgal infecting viruses (e.g., family Narnaviridae, family Totitiviridae, and family Yueviridae). Finally, we demonstrate that the RNA viral diversity of the HRAP is temporally dynamic across two successive culturing seasons.
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Affiliation(s)
- Emily E. Chase
- Microbiologie Environnementale Biotechnologie, Institut Méditerranéen d’Océanologie, 163 Avenue de Luminy, 13009 Marseille, France; (S.M.-B.); (F.H.A.)
- Institut Hospitalo-Universitaire (IHU) Méditerranée Infection, 19-21 Boulevard Jean Moulin, 13005 Marseille, France
| | - Sonia Monteil-Bouchard
- Microbiologie Environnementale Biotechnologie, Institut Méditerranéen d’Océanologie, 163 Avenue de Luminy, 13009 Marseille, France; (S.M.-B.); (F.H.A.)
| | - Angélique Gobet
- MARBEC University Montpellier, CNRS, Ifremer, IRD, 34203 Sète, France;
| | - Felana H. Andrianjakarivony
- Microbiologie Environnementale Biotechnologie, Institut Méditerranéen d’Océanologie, 163 Avenue de Luminy, 13009 Marseille, France; (S.M.-B.); (F.H.A.)
- Institut Hospitalo-Universitaire (IHU) Méditerranée Infection, 19-21 Boulevard Jean Moulin, 13005 Marseille, France
| | - Christelle Desnues
- Microbiologie Environnementale Biotechnologie, Institut Méditerranéen d’Océanologie, 163 Avenue de Luminy, 13009 Marseille, France; (S.M.-B.); (F.H.A.)
- Institut Hospitalo-Universitaire (IHU) Méditerranée Infection, 19-21 Boulevard Jean Moulin, 13005 Marseille, France
| | - Guillaume Blanc
- Microbiologie Environnementale Biotechnologie, Institut Méditerranéen d’Océanologie, 163 Avenue de Luminy, 13009 Marseille, France; (S.M.-B.); (F.H.A.)
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14
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Tomaru Y, Yamaguchi H, Miki T. Growth Rate-dependent Cell Death of Diatoms due to Viral Infection and Their Subsequent Coexistence in a Semi-continuous Culture System. Microbes Environ 2021; 36. [PMID: 33390375 PMCID: PMC7966941 DOI: 10.1264/jsme2.me20116] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Viral infections are a major factor in diatom cell death. However, the effects of viruses on diatom dynamics remain unclear. Based on laboratory studies, it is hypothesized that virus-induced diatom mortality is dependent on the diatom growth rate. The present study aimed to elucidate the relationship between the diatom growth rate and virus-induced mortality using model systems of the marine planktonic diatom, Chaetoceros tenuissimus and its infectious viruses. We also examined the fate of diatom populations in a semi-continuous dilution culture system, in which host growth rates were controlled at 0.69, 2.08, and 3.47 day–1. Diatom populations gradually decreased following the viral inoculation of each culture system, and virus-induced mortality inversely correlated with the diatom growth rate. Furthermore, the viral burst size was slightly higher in lower growth rate cultures. These results suggested that the host physiological status related to the growth rate affected viral infection and proliferation. Diatom populations were not completely lysed or washed out in any of the dilution systems; they showed steady growth in the presence of infectious viruses. This may be partially explained by defective interference particles from viruses and cell debris. The present results indicate that diatoms in dilution environments maintain their populations, even under viral pressure. Moreover, diatom populations with a low growth rate may partially sustain higher growth populations through nutrient recycling following virus-induced cell death. The results of the present study provide insights into diatom dynamics in natural environments in the presence of infectious viruses.
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Affiliation(s)
- Yuji Tomaru
- Hatsukaichi Field Station, Fisheries Technology Institute, Japan Fisheries Research and Education Agency, National Research and Development Agency
| | | | - Takeshi Miki
- Ecology and Environmental Engineering, Faculty of Advanced Science and Technology, Ryukoku University
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15
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Sadeghi M, Tomaru Y, Ahola T. RNA Viruses in Aquatic Unicellular Eukaryotes. Viruses 2021; 13:v13030362. [PMID: 33668994 PMCID: PMC7996518 DOI: 10.3390/v13030362] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 02/05/2021] [Accepted: 02/22/2021] [Indexed: 12/24/2022] Open
Abstract
Increasing sequence information indicates that RNA viruses constitute a major fraction of marine virus assemblages. However, only 12 RNA virus species have been described, infecting known host species of marine single-celled eukaryotes. Eight of these use diatoms as hosts, while four are resident in dinoflagellate, raphidophyte, thraustochytrid, or prasinophyte species. Most of these belong to the order Picornavirales, while two are divergent and fall into the families Alvernaviridae and Reoviridae. However, a very recent study has suggested that there is extraordinary diversity in aquatic RNA viromes, describing thousands of viruses, many of which likely use protist hosts. Thus, RNA viruses are expected to play a major ecological role for marine unicellular eukaryotic hosts. In this review, we describe in detail what has to date been discovered concerning viruses with RNA genomes that infect aquatic unicellular eukaryotes.
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Affiliation(s)
- Mohammadreza Sadeghi
- Department of Microbiology, Faculty of Agriculture and Forestry, University of Helsinki, 00014 Helsinki, Finland
- Correspondence: (M.S.); (T.A.)
| | - Yuji Tomaru
- Environment and Fisheries Applied Techniques Research Department, Fisheries Technology Institute, Fisheries Research and Education Agency, Hatsukaichi, Hiroshima 739-0452, Japan;
| | - Tero Ahola
- Department of Microbiology, Faculty of Agriculture and Forestry, University of Helsinki, 00014 Helsinki, Finland
- Correspondence: (M.S.); (T.A.)
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16
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Kinsella CM, Bart A, Deijs M, Broekhuizen P, Kaczorowska J, Jebbink MF, van Gool T, Cotten M, van der Hoek L. Entamoeba and Giardia parasites implicated as hosts of CRESS viruses. Nat Commun 2020; 11:4620. [PMID: 32934242 PMCID: PMC7493932 DOI: 10.1038/s41467-020-18474-w] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Accepted: 08/25/2020] [Indexed: 12/13/2022] Open
Abstract
Metagenomic techniques have enabled genome sequencing of unknown viruses without isolation in cell culture, but information on the virus host is often lacking, preventing viral characterisation. High-throughput methods capable of identifying virus hosts based on genomic data alone would aid evaluation of their medical or biological relevance. Here, we address this by linking metagenomic discovery of three virus families in human stool samples with determination of probable hosts. Recombination between viruses provides evidence of a shared host, in which genetic exchange occurs. We utilise networks of viral recombination to delimit virus-host clusters, which are then anchored to specific hosts using (1) statistical association to a host organism in clinical samples, (2) endogenous viral elements in host genomes, and (3) evidence of host small RNA responses to these elements. This analysis suggests two CRESS virus families (Naryaviridae and Nenyaviridae) infect Entamoeba parasites, while a third (Vilyaviridae) infects Giardia duodenalis. The trio supplements five CRESS virus families already known to infect eukaryotes, extending the CRESS virus host range to protozoa. Phylogenetic analysis implies CRESS viruses infecting multicellular life have evolved independently on at least three occasions.
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Affiliation(s)
- Cormac M Kinsella
- Laboratory of Experimental Virology, Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
| | - Aldert Bart
- Laboratory of Clinical Parasitology, Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Martin Deijs
- Laboratory of Experimental Virology, Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Patricia Broekhuizen
- Laboratory of Clinical Parasitology, Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Joanna Kaczorowska
- Laboratory of Experimental Virology, Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Maarten F Jebbink
- Laboratory of Experimental Virology, Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Tom van Gool
- Laboratory of Clinical Parasitology, Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Matthew Cotten
- MRC/UVRI & LSHTM Uganda Research Unit, 3FC6+Q3, Entebbe, Uganda
- MRC-University of Glasgow Centre for Virus Research, G61 1QH, Glasgow, UK
| | - Lia van der Hoek
- Laboratory of Experimental Virology, Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
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17
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Doubling of the known set of RNA viruses by metagenomic analysis of an aquatic virome. Nat Microbiol 2020; 5:1262-1270. [PMID: 32690954 PMCID: PMC7508674 DOI: 10.1038/s41564-020-0755-4] [Citation(s) in RCA: 128] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 06/16/2020] [Indexed: 12/26/2022]
Abstract
RNA viruses in aquatic environments remain poorly studied. Here, we analysed the RNA virome from approximately 10 l water from Yangshan Deep-Water Harbour near the Yangtze River estuary in China and identified more than 4,500 distinct RNA viruses, doubling the previously known set of viruses. Phylogenomic analysis identified several major lineages, roughly, at the taxonomic ranks of class, order and family. The 719-member-strong Yangshan virus assemblage is the sister clade to the expansive class Alsuviricetes and consists of viruses with simple genomes that typically encode only RNA-dependent RNA polymerase (RdRP), capping enzyme and capsid protein. Several clades within the Yangshan assemblage independently evolved domain permutation in the RdRP. Another previously unknown clade shares ancestry with Potyviridae, the largest known plant virus family. The ‘Aquatic picorna-like viruses/Marnaviridae’ clade was greatly expanded, with more than 800 added viruses. Several RdRP-linked protein domains not previously detected in any RNA viruses were identified, such as the small ubiquitin-like modifier (SUMO) domain, phospholipase A2 and PrsW-family protease domain. Multiple viruses utilize alternative genetic codes implying protist (especially ciliate) hosts. The results reveal a vast RNA virome that includes many previously unknown groups. However, phylogenetic analysis of the RdRPs supports the previously established five-branch structure of the RNA virus evolutionary tree, with no additional phyla. Metagenomic analysis of a single RNA virome from the Yangshan Deep-Water Harbour in China enabled the recovery of more than 4,500 distinct RNA viruses, doubling the known set of RNA viruses to date, and provided insights into their biology.
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18
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Kadono T, Tomaru Y, Suzuki K, Yamada K, Adachi M. The possibility of using marine diatom-infecting viral promoters for the engineering of marine diatoms. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2020; 296:110475. [PMID: 32540005 DOI: 10.1016/j.plantsci.2020.110475] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Revised: 02/26/2020] [Accepted: 03/18/2020] [Indexed: 06/11/2023]
Abstract
Marine diatoms constitute a major group of unicellular photosynthetic eukaryotes. Diatoms are widely applicable for both basic studies and applied studies. Molecular tools and techniques have been developed for diatom research. Among these tools, several endogenous gene promoters (e.g., the fucoxanthin chlorophyll a/c-binding protein gene promoter) have become available for expressing transgenes in diatoms. Gene promoters that drive transgene expression at a high level are very important for the metabolic engineering of diatoms. Various marine diatom-infecting viruses (DIVs), including both DNA viruses and RNA viruses, have recently been isolated, and their genome sequences have been characterized. Promoters from viruses that infect plants and mammals are widely used as constitutive promoters to achieve high expression of transgenes. Thus, we recently investigated the activity of promoters derived from marine DIVs in the marine diatom, Phaeodactylum tricornutum. We discuss novel viral promoters that will be useful for the future metabolic engineering of diatoms.
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Affiliation(s)
- Takashi Kadono
- Laboratory of Aquatic Environmental Science, Faculty of Agriculture and Marine Science, Kochi University, Otsu-200, Monobe, Nankoku, Kochi, 783-8502, Japan
| | - Yuji Tomaru
- National Research Institute of Fisheries and Environment of Inland Sea, Japan Fisheries Research and Education Agency, 2-17-5 Maruishi, Hatsukaichi, Hiroshima, 739-0452, Japan
| | - Kengo Suzuki
- euglena Co., Ltd., G-BASE Tamachi 2nd and 3rd Floor 5-29-11 Shiba Minato-ku, Tokyo, 108-0014, Japan
| | - Koji Yamada
- euglena Co., Ltd., G-BASE Tamachi 2nd and 3rd Floor 5-29-11 Shiba Minato-ku, Tokyo, 108-0014, Japan
| | - Masao Adachi
- Laboratory of Aquatic Environmental Science, Faculty of Agriculture and Marine Science, Kochi University, Otsu-200, Monobe, Nankoku, Kochi, 783-8502, Japan.
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19
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Pound HL, Gann ER, Tang X, Krausfeldt LE, Huff M, Staton ME, Talmy D, Wilhelm SW. The "Neglected Viruses" of Taihu: Abundant Transcripts for Viruses Infecting Eukaryotes and Their Potential Role in Phytoplankton Succession. Front Microbiol 2020; 11:338. [PMID: 32210938 PMCID: PMC7067694 DOI: 10.3389/fmicb.2020.00338] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 02/17/2020] [Indexed: 01/18/2023] Open
Abstract
Drivers of algal bloom dynamics remain poorly understood, but viruses have been implicated as important players. Research addressing bloom dynamics has generally been restricted to the virus-infection of the numerically dominant (i.e. bloom forming) taxa. Yet this approach neglects a broad diversity of viral groups, limiting our knowledge of viral interactions and constraints within these systems. We examined hallmark virus marker genes in metatranscriptomic libraries from a seasonal and spatial survey of a Microcystis aeruginosa bloom in Lake Tai (Taihu) China to identify active infections by nucleocytoplasmic large DNA viruses (NCLDVs), RNA viruses, ssDNA viruses, bacteriophage, and virophage. Phylogenetic analyses revealed a diverse virus population with seasonal and spatial variability. We observed disproportionately high expression of markers associated with NCLDVs and ssRNA viruses (consistent with viruses that infect photosynthetic protists) relative to bacteriophage infecting heterotrophic bacteria or cyanobacteria during the height of the Microcystis bloom event. Under a modified kill-the-winner scheme, we hypothesize viruses infecting protists help suppress the photosynthetic eukaryotic community and allow for the proliferation of cyanobacteria such as Microcystis. Our observations provide a foundation for a little considered factor promoting algal blooms.
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Affiliation(s)
- Helena L Pound
- Department of Microbiology, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Eric R Gann
- Department of Microbiology, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Xiangming Tang
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
| | - Lauren E Krausfeldt
- Department of Microbiology, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Matthew Huff
- Department of Entomology and Plant Pathology, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Margaret E Staton
- Department of Entomology and Plant Pathology, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - David Talmy
- Department of Microbiology, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Steven W Wilhelm
- Department of Microbiology, The University of Tennessee, Knoxville, Knoxville, TN, United States
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20
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Vlok M, Lang AS, Suttle CA. Application of a sequence-based taxonomic classification method to uncultured and unclassified marine single-stranded RNA viruses in the order Picornavirales. Virus Evol 2019; 5:vez056. [PMID: 31908848 PMCID: PMC6938265 DOI: 10.1093/ve/vez056] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Metagenomics has altered our understanding of microbial diversity and ecology. This includes its applications to viruses in marine environments that have demonstrated their enormous diversity. Within these are RNA viruses, many of which share genetic features with members of the order Picornavirales; yet, very few of these have been taxonomically classified. The only recognized family of marine RNA viruses is the Marnaviridae, which was founded based on discovery and characterization of the species Heterosigma akashiwo RNA virus. Two additional genera of marine RNA viruses, Labyrnavirus (one species) and Bacillarnavirus (three species), were subsequently defined within the order Picornavirales but not assigned to a family. We have defined a sequence-based framework for taxonomic classification of twenty marine RNA viruses into the family Marnaviridae. Using RNA-dependent RNA polymerase (RdRp) phylogeny and distance-based analyses, we assigned the genera Labyrnavirus and Bacillarnavirus to the family Marnaviridae and created four additional genera in the family: Locarnavirus (four species), Kusarnavirus (one species), Salisharnavirus (four species) and Sogarnavirus (six species). We used pairwise capsid protein comparisons to delineate species within families, with 75 per cent identity as the species demarcation threshold. The family displays high sequence diversities and Jukes-Cantor distances for both the RdRp and capsid genes, suggesting that the classified viruses are not representative of all of the virus diversity within the family and that there are many more extant taxa. Our proposed taxonomic framework provides a sound classification system for this group of viruses that will have broadly applicable principles for other viral groups. It is based on sequence data alone and provides a robust taxonomic framework to include viruses discovered via metagenomic studies, thereby greatly expanding the realm of viruses subject to taxonomic classification.
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Affiliation(s)
- Marli Vlok
- Department of Botany, University of British Columbia, 6270 University Blvd., Vancouver, BC V6T 1Z4, Canada.,Institute for the Oceans and Fisheries, University of British Columbia, 2202 Main Mall, Vancouver, BC V6T 1Z4, Canada
| | - Andrew S Lang
- Department of Biology, Memorial University of Newfoundland, 232 Elizabeth Ave., St. John's, NL A1B 3X9, Canada
| | - Curtis A Suttle
- Department of Botany, University of British Columbia, 6270 University Blvd., Vancouver, BC V6T 1Z4, Canada.,Institute for the Oceans and Fisheries, University of British Columbia, 2202 Main Mall, Vancouver, BC V6T 1Z4, Canada.,Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, 2207 Main Mall, Vancouver, BC V6T 1Z4, Canada.,Department of Microbiology and Immunology, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z4, Canada
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21
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Benites LF, Poulton N, Labadie K, Sieracki ME, Grimsley N, Piganeau G. Single cell ecogenomics reveals mating types of individual cells and ssDNA viral infections in the smallest photosynthetic eukaryotes. Philos Trans R Soc Lond B Biol Sci 2019; 374:20190089. [PMID: 31587637 DOI: 10.1098/rstb.2019.0089] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Planktonic photosynthetic organisms of the class Mamiellophyceae include the smallest eukaryotes (less than 2 µm), are globally distributed and form the basis of coastal marine ecosystems. Eight complete fully annotated 13-22 Mb genomes from three genera, Ostreococcus, Bathycoccus and Micromonas, are available from previously isolated clonal cultured strains and provide an ideal resource to explore the scope and challenges of analysing single cell amplified genomes (SAGs) isolated from a natural environment. We assembled data from 12 SAGs sampled during the Tara Oceans expedition to gain biological insights about their in situ ecology, which might be lost by isolation and strain culture. Although the assembled nuclear genomes were incomplete, they were large enough to infer the mating types of four Ostreococcus SAGs. The systematic occurrence of sequences from the mitochondria and chloroplast, representing less than 3% of the total cell's DNA, intimates that SAGs provide suitable substrates for detection of non-target sequences, such as those of virions. Analysis of the non-Mamiellophyceae assemblies, following filtering out cross-contaminations during the sequencing process, revealed two novel 1.6 and 1.8 kb circular DNA viruses, and the presence of specific Bacterial and Oomycete sequences suggests that these organisms might co-occur with the Mamiellales. This article is part of a discussion meeting issue 'Single cell ecology'.
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Affiliation(s)
- L Felipe Benites
- Integrative Biology of Marine Organisms (BIOM), Sorbonne University, CNRS, Oceanological Observatory of Banyuls, 66650 Banyuls-sur-Mer, France
| | - Nicole Poulton
- Bigelow Laboratory for Ocean Sciences, East Boothbay, ME 04544, USA
| | - Karine Labadie
- Genoscope, Institut de Biologie François-Jacob, Commissariat à l'Energie Atomique, université Paris Saclay, 9105 Evry, France
| | | | - Nigel Grimsley
- Integrative Biology of Marine Organisms (BIOM), Sorbonne University, CNRS, Oceanological Observatory of Banyuls, 66650 Banyuls-sur-Mer, France
| | - Gwenael Piganeau
- Integrative Biology of Marine Organisms (BIOM), Sorbonne University, CNRS, Oceanological Observatory of Banyuls, 66650 Banyuls-sur-Mer, France
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22
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Silicon limitation facilitates virus infection and mortality of marine diatoms. Nat Microbiol 2019; 4:1790-1797. [PMID: 31308524 DOI: 10.1038/s41564-019-0502-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 05/30/2019] [Indexed: 01/09/2023]
Abstract
Diatoms are among the most globally distributed and ecologically successful organisms in the modern ocean, contributing upwards of 40% of total marine primary productivity1,2. By converting dissolved silicon into biogenic silica, and photosynthetically fixing carbon dioxide into particulate organic carbon, diatoms effectively couple the silicon (Si) and carbon cycles and ballast substantial vertical flux of carbon out of the euphotic zone into the mesopelagic and deep ocean3-5. Viruses are key players in ocean biogeochemical cycles6,7, yet little is known about how viral infection specifically impacts diatom populations. Here, we show that Si limitation facilitates virus infection and mortality in diatoms in the highly productive coastal waters of the California Current Ecosystem. Using metatranscriptomic analysis of cell-associated diatom viruses and targeted quantification of extracellular viruses, we found a link between Si stress and the early, active and lytic stages of viral infection. This relationship was also observed in cultures of the bloom-forming diatom Chaetoceros tenuissimus, where Si stress accelerated virus-induced mortality. Together, these findings contextualize viruses within the ecophysiological framework of Si availability and diatom-mediated biogeochemical cycling.
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23
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Abstract
Very little is known about aquatic RNA virus populations and genome evolution. This is the first study that analyzes marine environmental RNA viral assemblages in an evolutionary and broad geographical context. This study contributes the largest marine RNA virus metagenomic data set to date, substantially increasing the sequencing space for RNA viruses and also providing a baseline for comparisons of marine RNA virus diversity. The new viruses discovered in this study are representative of the most abundant family of marine RNA viruses, the Marnaviridae, and expand our view of the diversity of this important group. Overall, our data and analyses provide a foundation for interpreting marine RNA virus diversity and evolution. RNA viruses, particularly genetically diverse members of the Picornavirales, are widespread and abundant in the ocean. Gene surveys suggest that there are spatial and temporal patterns in the composition of RNA virus assemblages, but data on their diversity and genetic variability in different oceanographic settings are limited. Here, we show that specific RNA virus genomes have widespread geographic distributions and that the dominant genotypes are under purifying selection. Genomes from three previously unknown picorna-like viruses (BC-1, -2, and -3) assembled from a coastal site in British Columbia, Canada, as well as marine RNA viruses JP-A, JP-B, and Heterosigma akashiwo RNA virus exhibited different biogeographical patterns. Thus, biotic factors such as host specificity and viral life cycle, and not just abiotic processes such as dispersal, affect marine RNA virus distribution. Sequence differences relative to reference genomes imply that virus quasispecies are under purifying selection, with synonymous single-nucleotide variations dominating in genomes from geographically distinct regions resulting in conservation of amino acid sequences. Conversely, sequences from coastal South Africa that mapped to marine RNA virus JP-A exhibited more nonsynonymous mutations, probably representing amino acid changes that accumulated over a longer separation. This biogeographical analysis of marine RNA viruses demonstrates that purifying selection is occurring across oceanographic provinces. These data add to the spectrum of known marine RNA virus genomes, show the importance of dispersal and purifying selection for these viruses, and indicate that closely related RNA viruses are pathogens of eukaryotic microbes across oceans. IMPORTANCE Very little is known about aquatic RNA virus populations and genome evolution. This is the first study that analyzes marine environmental RNA viral assemblages in an evolutionary and broad geographical context. This study contributes the largest marine RNA virus metagenomic data set to date, substantially increasing the sequencing space for RNA viruses and also providing a baseline for comparisons of marine RNA virus diversity. The new viruses discovered in this study are representative of the most abundant family of marine RNA viruses, the Marnaviridae, and expand our view of the diversity of this important group. Overall, our data and analyses provide a foundation for interpreting marine RNA virus diversity and evolution.
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24
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Arsenieff L, Simon N, Rigaut-Jalabert F, Le Gall F, Chaffron S, Corre E, Com E, Bigeard E, Baudoux AC. First Viruses Infecting the Marine Diatom Guinardia delicatula. Front Microbiol 2019; 9:3235. [PMID: 30687251 PMCID: PMC6334475 DOI: 10.3389/fmicb.2018.03235] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 12/12/2018] [Indexed: 11/17/2022] Open
Abstract
The marine diatom Guinardia delicatula is a cosmopolitan species that dominates seasonal blooms in the English Channel and the North Sea. Several eukaryotic parasites are known to induce the mortality of this species. Here, we report the isolation and characterization of the first viruses that infect G. delicatula. Viruses were isolated from the Western English Channel (SOMLIT-Astan station) during the late summer bloom decline of G. delicatula. A combination of laboratory approaches revealed that these lytic viruses (GdelRNAV) are small tailless particles of 35–38 nm in diameter that replicate in the host cytoplasm where both unordered particles and crystalline arrays are formed. GdelRNAV display a linear single-stranded RNA genome of ~9 kb, including two open reading frames encoding for replication and structural polyproteins. Phylogenetic relationships based on the RNA-dependent-RNA-polymerase gene marker showed that GdelRNAV are new members of the Bacillarnavirus, a monophyletic genus belonging to the order Picornavirales. GdelRNAV are specific to several strains of G. delicatula. They were rapidly and largely produced (<12 h, 9.34 × 104 virions per host cell). Our analysis points out the host's variable viral susceptibilities during the early exponential growth phase. Interestingly, we consistently failed to isolate viruses during spring and early summer while G. delicatula developed important blooms. While our study suggests that viruses do contribute to the decline of G. delicatula's late summer bloom, they may not be the primary mortality agents during the remaining blooms at SOMLIT-Astan. Future studies should focus on the relative contribution of the viral and eukaryotic pathogens to the control of Guinardia's blooms to understand the fate of these prominent organisms in marine systems.
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Affiliation(s)
- Laure Arsenieff
- Sorbonne Université, CNRS UMR 7144, Diversity and Interactions in Oceanic Plankton - Station Biologique de Roscoff, Roscoff, France
| | - Nathalie Simon
- Sorbonne Université, CNRS UMR 7144, Diversity and Interactions in Oceanic Plankton - Station Biologique de Roscoff, Roscoff, France
| | - Fabienne Rigaut-Jalabert
- Sorbonne Université, CNRS Fédération de Recherche FR2424 - Station Biologique de Roscoff, Roscoff, France
| | - Florence Le Gall
- Sorbonne Université, CNRS UMR 7144, Diversity and Interactions in Oceanic Plankton - Station Biologique de Roscoff, Roscoff, France
| | - Samuel Chaffron
- Laboratoire des Sciences du Numérique de Nantes (LS2N), CNRS UMR 6004 - Université de Nantes, Nantes, France
| | - Erwan Corre
- Sorbonne Université, CNRS Fédération de Recherche FR2424 - Station Biologique de Roscoff, Roscoff, France
| | - Emmanuelle Com
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, Rennes, France.,Protim, Univ Rennes, Rennes, France
| | - Estelle Bigeard
- Sorbonne Université, CNRS UMR 7144, Diversity and Interactions in Oceanic Plankton - Station Biologique de Roscoff, Roscoff, France
| | - Anne-Claire Baudoux
- Sorbonne Université, CNRS UMR 7144, Diversity and Interactions in Oceanic Plankton - Station Biologique de Roscoff, Roscoff, France
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25
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Viruses of Eukaryotic Algae: Diversity, Methods for Detection, and Future Directions. Viruses 2018; 10:v10090487. [PMID: 30208617 PMCID: PMC6165237 DOI: 10.3390/v10090487] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 09/04/2018] [Accepted: 09/07/2018] [Indexed: 11/16/2022] Open
Abstract
The scope for ecological studies of eukaryotic algal viruses has greatly improved with the development of molecular and bioinformatic approaches that do not require algal cultures. Here, we review the history and perceived future opportunities for research on eukaryotic algal viruses. We begin with a summary of the 65 eukaryotic algal viruses that are presently in culture collections, with emphasis on shared evolutionary traits (e.g., conserved core genes) of each known viral type. We then describe how core genes have been used to enable molecular detection of viruses in the environment, ranging from PCR-based amplification to community scale "-omics" approaches. Special attention is given to recent studies that have employed network-analyses of -omics data to predict virus-host relationships, from which a general bioinformatics pipeline is described for this type of approach. Finally, we conclude with acknowledgement of how the field of aquatic virology is adapting to these advances, and highlight the need to properly characterize new virus-host systems that may be isolated using preliminary molecular surveys. Researchers can approach this work using lessons learned from the Chlorella virus system, which is not only the best characterized algal-virus system, but is also responsible for much of the foundation in the field of aquatic virology.
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26
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Abstract
Viruses are integral to ecological and evolutionary processes, but we have a poor understanding of what drives variation in key traits across diverse viruses. For lytic viruses, burst size, latent period, and genome size are primary characteristics controlling host-virus dynamics. Here we synthesize data on these traits for 75 strains of phytoplankton viruses, which play an important role in global biogeochemistry. We find that primary traits of the host (genome size, growth rate) explain 40%-50% of variation in burst size and latent period. Specifically, burst size and latent period both exhibit saturating relationships versus the host∶virus genome size ratio, with both traits increasing at low genome size ratios while showing no relationship at high size ratios. In addition, latent period declines as host growth rate increases. We analyze a model of latent period evolution to explore mechanisms that could cause these patterns. The model predicts that burst size may often be set by the host genomic resources available for viral construction, while latent period evolves to permit this maximal burst size, modulated by host metabolic rate. These results suggest that general mechanisms may underlie the evolution of diverse viruses. Future extensions of this work could help explain viral regulation of host populations, viral influence on community structure and diversity, and viral roles in biogeochemical cycles.
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27
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Culley A. New insight into the RNA aquatic virosphere via viromics. Virus Res 2017; 244:84-89. [PMID: 29138044 DOI: 10.1016/j.virusres.2017.11.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 11/07/2017] [Accepted: 11/07/2017] [Indexed: 01/09/2023]
Abstract
RNA viruses that infect microbes are now recognized as an active, persistent and important component of the aquatic microbial community. While some information about the diversity and dynamics of the RNA virioplankton has been derived from culture-based and single gene approaches, research based on viromic and metatransciptomic methods has generated unprecedented insight into this relatively understudied class of microbes. Here, the relevant literature is summarized and discussed, including viromic studies of extracellular aquatic RNA viral assemblages, and transcriptomic studies of active and associated RNA viruses from aquatic environments followed by commentary on the present challenges and future directions of this field of research.
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Affiliation(s)
- Alexander Culley
- Département de biochimie, de microbiologie et de bio-informatique, Université Laval, Québec, Québec, G1V 0A6, Canada; Centre d'études nordiques (CEN), Université Laval, Québec, Québec, G1V 0A6, Canada; Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec, G1V 0A6, Canada; Takuvik, Unité Mixte Interntionale (UMI 3376) Université Laval (Canada) & Centre National de la Recherche Scientifique (France), Québec QC GIV 0A6, Canada.
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28
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Metagenomics reshapes the concepts of RNA virus evolution by revealing extensive horizontal virus transfer. Virus Res 2017; 244:36-52. [PMID: 29103997 PMCID: PMC5801114 DOI: 10.1016/j.virusres.2017.10.020] [Citation(s) in RCA: 137] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 10/30/2017] [Accepted: 10/31/2017] [Indexed: 12/22/2022]
Abstract
Virus metagenomics is a young research filed but it has already transformed our understanding of virus diversity and evolution, and illuminated at a new level the connections between virus evolution and the evolution and ecology of the hosts. In this review article, we examine the new picture of the evolution of RNA viruses, the dominant component of the eukaryotic virome, that is emerging from metagenomic data analysis. The major expansion of many groups of RNA viruses through metagenomics allowed the construction of substantially improved phylogenetic trees for the conserved virus genes, primarily, the RNA-dependent RNA polymerases (RdRp). In particular, a new superfamily of widespread, small positive-strand RNA viruses was delineated that unites tombus-like and noda-like viruses. Comparison of the genome architectures of RNA viruses discovered by metagenomics and by traditional methods reveals an extent of gene module shuffling among diverse virus genomes that far exceeds the previous appreciation of this evolutionary phenomenon. Most dramatically, inclusion of the metagenomic data in phylogenetic analyses of the RdRp resulted in the identification of numerous, strongly supported groups that encompass RNA viruses from diverse hosts including different groups of protists, animals and plants. Notwithstanding potential caveats, in particular, incomplete and uneven sampling of eukaryotic taxa, these highly unexpected findings reveal horizontal virus transfer (HVT) between diverse hosts as the central aspect of RNA virus evolution. The vast and diverse virome of invertebrates, particularly nematodes and arthropods, appears to be the reservoir, from which the viromes of plants and vertebrates evolved via multiple HVT events.
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29
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Carlson MCG, McCary ND, Leach TS, Rocap G. Pseudo-nitzschia Challenged with Co-occurring Viral Communities Display Diverse Infection Phenotypes. Front Microbiol 2016; 7:527. [PMID: 27148216 PMCID: PMC4837327 DOI: 10.3389/fmicb.2016.00527] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Accepted: 03/31/2016] [Indexed: 11/13/2022] Open
Abstract
Viruses are catalysts of biogeochemical cycling, architects of microbial community structure, and terminators of phytoplankton blooms. Viral lysis of diatoms, a key group of eukaryotic phytoplankton, has the potential to impact carbon export and marine food webs. However, the impact of viruses on diatom abundance and community composition is unknown. Diatom-virus dynamics were explored by sampling every month at two coastal and estuarine locations in Washington state, USA resulting in 41 new isolates of the pennate diatom Pseudo-nitzschia and 20 environmental virus samples. We conducted a total of 820 pair-wise crosses of the Pseudo-nitzschia isolates and viral communities. Viral communities infected Pseudo-nitzschia isolates in 8% of the crosses overall and 16% of crosses when the host and viral communities were isolated from the same sample. Isolates ranged in their permissivity to infection with some isolates not infected by any viral samples and others infected by up to 10 viral communities. Isolates that were infected by the most viral communities also had the highest maximum observed viral titers (as high as 16000 infectious units ml-1). Titers of the viral communities were host dependent, as titers for one viral sample on eight different hosts spanned four orders of magnitude. Sequencing of the Pseudo-nitzschia Internal Transcribed Spacer 1 (ITS1) of the revealed multiple subgroups of hosts with 100% ITS1 identities that were infected by different viral communities. Indeed, we repeatedly isolated groups of isolates with identical ITS1 sequences from the same water sample that displayed different viral infection phenotypes. The interactions between Pseudo-nitzschia and the viral communities highlight the diversity of diatoms and emphasize the complexity and variability of diatom-virus dynamics in the ocean.
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Affiliation(s)
| | | | - Terence S Leach
- School of Oceanography, University of Washington Seattle, WA, USA
| | - Gabrielle Rocap
- School of Oceanography, University of Washington Seattle, WA, USA
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30
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Lachnit T, Thomas T, Steinberg P. Expanding our Understanding of the Seaweed Holobiont: RNA Viruses of the Red Alga Delisea pulchra. Front Microbiol 2016; 6:1489. [PMID: 26779145 PMCID: PMC4705237 DOI: 10.3389/fmicb.2015.01489] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 12/10/2015] [Indexed: 01/08/2023] Open
Abstract
Marine seaweeds are holobionts comprised of the macroalgal hosts and their associated microbiota. While the composition of the bacterial component of seaweed microbiomes is increasingly studied, almost nothing is known about the presence, diversity and composition of viruses in macroalgae in situ. In this study, we characterize for the first time the viruses associated with a red macroalga, Delisea pulchra. Using transmission electron microscopy we identified diverse morphotypes of virus-like particles in D. pulchra ranging from icosahedral to bacilliform to coiled pleomorphic as well as bacteriophages. Virome sequencing revealed the presence of a diverse group of dsRNA viruses affiliated to the genus Totivirus, known to infect plant pathogenic fungi. We further identified a ssRNA virus belonging to the order Picornavirales with a close phylogenetic relationship to a pathogenic virus infecting marine diatoms. The results of this study shed light on a so far neglected part of the seaweed holobiont, and suggest that some of the identified viruses may be possible pathogens for a host that is already known to be significantly impacted by bacterial infections.
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Affiliation(s)
- Tim Lachnit
- Centre for Marine Bio-Innovation, University of New South Wales, SydneyNSW, Australia
- Zoological Institute, Christian-Albrechts-University KielKiel, Germany
| | - Torsten Thomas
- Centre for Marine Bio-Innovation, University of New South Wales, SydneyNSW, Australia
- School for Biotechnology and Biomolecular Science, University of New South Wales, SydneyNSW, Australia
| | - Peter Steinberg
- Centre for Marine Bio-Innovation, University of New South Wales, SydneyNSW, Australia
- School of Biological, Earth and Environmental Sciences, University of New South Wales, SydneyNSW, Australia
- Sydney Institute of Marine Science, MosmanNSW, Australia
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31
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Abstract
Viral ecology is a rapidly progressing area of research, as molecular methods have improved significantly for targeted research on specific populations and whole communities. To interpret and synthesize global viral diversity and distribution, it is feasible to assess whether macroecology concepts can apply to marine viruses. We review how viral and host life history and physical properties can influence viral distribution in light of biogeography and metacommunity ecology paradigms. We highlight analytical approaches that can be applied to emerging global data sets and meta-analyses to identify individual taxa with global influence and drivers of emergent properties that influence microbial community structure by drawing on examples across the spectrum of viral taxa, from RNA to ssDNA and dsDNA viruses.
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Affiliation(s)
| | - Curtis A Suttle
- Department of Earth, Ocean, and Atmospheric Sciences.,Department of Botany, and.,Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada; .,Integrated Microbial Biodiversity Program, Canadian Institute for Advanced Research, Toronto, Ontario M5G 1Z8, Canada
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32
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López-Bueno A, Rastrojo A, Peiró R, Arenas M, Alcamí A. Ecological connectivity shapes quasispecies structure of RNA viruses in an Antarctic lake. Mol Ecol 2015. [DOI: 10.1111/mec.13321] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- A. López-Bueno
- Department of Virology and Microbiology; Centro de Biología Molecular ‘Severo Ochoa’ (Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid); Nicolás Cabrera 1 Cantoblanco 28049 Madrid Spain
| | - A. Rastrojo
- Department of Virology and Microbiology; Centro de Biología Molecular ‘Severo Ochoa’ (Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid); Nicolás Cabrera 1 Cantoblanco 28049 Madrid Spain
| | - R. Peiró
- Department of Virology and Microbiology; Centro de Biología Molecular ‘Severo Ochoa’ (Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid); Nicolás Cabrera 1 Cantoblanco 28049 Madrid Spain
| | - M. Arenas
- Department of Virology and Microbiology; Centro de Biología Molecular ‘Severo Ochoa’ (Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid); Nicolás Cabrera 1 Cantoblanco 28049 Madrid Spain
| | - A. Alcamí
- Department of Virology and Microbiology; Centro de Biología Molecular ‘Severo Ochoa’ (Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid); Nicolás Cabrera 1 Cantoblanco 28049 Madrid Spain
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Kim J, Kim CH, Youn SH, Choi TJ. Isolation and Physiological Characterization of a Novel Algicidal Virus Infecting the Marine Diatom Skeletonema costatum. THE PLANT PATHOLOGY JOURNAL 2015; 31:186-191. [PMID: 26060438 PMCID: PMC4454000 DOI: 10.5423/ppj.nt.03.2015.0029] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Revised: 03/28/2015] [Accepted: 04/07/2015] [Indexed: 06/04/2023]
Abstract
Diatoms are a major component of the biological community, serving as the principal primary producers in the food web and sustaining oxygen levels in aquatic environments. Among marine planktonic diatoms, the cosmopolitan Skeletonema costatum is one of the most abundant and widespread species in the world's oceans. Here, we report the basic characteristics of a new diatom-infecting S. costatum virus (ScosV) isolated from Jaran Bay, Korea, in June 2008. ScosV is a polyhedral virus (45-50 nm in diameter) that propagates in the cytoplasm of host cells and causes lysis of S. costatum cultures. The infectivity of ScosV was determined to be strain- rather than species-specific, similar to other algal viruses. The burst size and latent period were roughly estimated at 90-250 infectious units/cell and <48 h, respectively.
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Affiliation(s)
- JinJoo Kim
- Fishery and Ocean Information Division, National Fisheries Research & Development Institute, Busan 619-705,
Korea
| | - Chang-Hoon Kim
- Department of Marine Bio-materials and Aquaculture, Pukyong National University, Busan 608-737,
Korea
| | - Seok-Hyun Youn
- Fishery and Ocean Information Division, National Fisheries Research & Development Institute, Busan 619-705,
Korea
| | - Tae-Jin Choi
- Department of Microbiology, Pukyong National University, Busan 608-737,
Korea
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Gustavsen JA, Winget DM, Tian X, Suttle CA. High temporal and spatial diversity in marine RNA viruses implies that they have an important role in mortality and structuring plankton communities. Front Microbiol 2014; 5:703. [PMID: 25566218 PMCID: PMC4266044 DOI: 10.3389/fmicb.2014.00703] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 11/26/2014] [Indexed: 01/26/2023] Open
Abstract
Viruses in the order Picornavirales infect eukaryotes, and are widely distributed in coastal waters. Amplicon deep-sequencing of the RNA dependent RNA polymerase (RdRp) revealed diverse and highly uneven communities of picorna-like viruses in the coastal waters of British Columbia (BC), Canada. Almost 300 000 pyrosequence reads revealed 145 operational taxonomic units (OTUs) based on 95% sequence similarity at the amino-acid level. Each sample had between 24 and 71 OTUs and there was little overlap among samples. Phylogenetic analysis revealed that some clades of OTUs were only found at one site; whereas, other clades included OTUs from all sites. Since most of these OTUs are likely from viruses that infect eukaryotic phytoplankton, and viral isolates infecting phytoplankton are strain-specific; each OTU probably arose from the lysis of a specific phytoplankton taxon. Moreover, the patchiness in OTU distribution, and the high turnover of viruses in the mixed layer, implies continuous infection and lysis by RNA viruses of a diverse array of eukaryotic phytoplankton taxa. Hence, these viruses are likely important elements structuring the phytoplankton community, and play a significant role in nutrient cycling and energy transfer.
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Affiliation(s)
- Julia A Gustavsen
- Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia Vancouver, BC, Canada
| | - Danielle M Winget
- Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia Vancouver, BC, Canada
| | - Xi Tian
- Bioinformatics Graduate Program, Faculty of Science, University of British Columbia Vancouver, BC, Canada
| | - Curtis A Suttle
- Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia Vancouver, BC, Canada ; Departments of Botany, and Microbiology & Immunology, University of British Columbia Vancouver, BC, Canada ; Canadian Institute for Advanced Research Toronto, ON, Canada
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Discovery of two novel viruses expands the diversity of single-stranded DNA and single-stranded RNA viruses infecting a cosmopolitan marine diatom. Appl Environ Microbiol 2014; 81:1120-31. [PMID: 25452289 DOI: 10.1128/aem.02380-14] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Recent studies have suggested that diatom viruses are an important factor affecting diatom population dynamics, which in turn are important in considering marine primary productivity. The marine planktonic diatom Chaetoceros tenuissimus Meunier is a cosmopolitan species and often causes blooms off the western coast of Japan. To date, two viruses, C. tenuissimus DNA virus (CtenDNAV) type I and CtenRNAV type I, have been identified that potentially affect C. tenuissimus population dynamics in the natural environment. In this study, we successfully isolated and characterized two additional novel viruses (CtenDNAV type II and CtenRNAV type II). This paper reports the basic characteristics of these new viruses isolated from surface water or sediment from the Hiroshima Bay, Japan. The physiological and morphological characteristics of the two new viruses were similar to those of the previously isolated viruses. However, the amino acid sequences of the structural proteins of CtenDNAV type II and CtenRNAV type II were clearly distinct from those of both type I viruses, with identity scores of 38.3% and 27.6%, respectively. Our results suggest that at least four genetically distinct viruses sharing the same diatom host are present in western Japan and affect the population dynamics of C. tenuissimus. Moreover, the result that CtenRNAV type II lysed multiple diatom species indicates that RNA viruses may affect various diatom populations in the natural environment.
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Abstract
UNLABELLED Viruses have a profound influence on the ecology and evolution of plankton, but our understanding of the composition of the aquatic viral communities is still rudimentary. This is especially true of those viruses having RNA genomes. The limited data that have been published suggest that the RNA virioplankton is dominated by viruses with positive-sense, single-stranded (+ss) genomes that have features in common with those of eukaryote-infecting viruses in the order Picornavirales (picornavirads). In this study, we investigated the diversity of the RNA virus assemblages in tropical coastal seawater samples using targeted PCR and metagenomics. Amplification of RNA-dependent RNA polymerase (RdRp) genes from fractions of a buoyant density gradient suggested that the distribution of two major subclades of the marine picornavirads was largely congruent with the distribution of total virus-like RNA, a finding consistent with their proposed dominance. Analyses of the RdRp sequences in the library revealed the presence of many diverse phylotypes, most of which were related only distantly to those of cultivated viruses. Phylogenetic analysis suggests that there were hundreds of unique picornavirad-like phylotypes in one 35-liter sample that differed from one another by at least as much as the differences among currently recognized species. Assembly of the sequences in the metagenome resulted in the reconstruction of six essentially complete viral genomes that had features similar to viruses in the families Bacillarna-, Dicistro-, and Marnaviridae. Comparison of the tropical seawater metagenomes with those from other habitats suggests that +ssRNA viruses are generally the most common types of RNA viruses in aquatic environments, but biases in library preparation remain a possible explanation for this observation. IMPORTANCE Marine plankton account for much of the photosynthesis and respiration on our planet, and they influence the cycling of carbon and the distribution of nutrients on a global scale. Despite the fundamental importance of viruses to plankton ecology and evolution, most of the viruses in the sea, and the identities of their hosts, are unknown. This report is one of very few that delves into the genetic diversity within RNA-containing viruses in the ocean. The data expand the known range of viral diversity and shed new light on the physical properties and genetic composition of RNA viruses in the ocean.
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Mojica KDA, Brussaard CPD. Factors affecting virus dynamics and microbial host-virus interactions in marine environments. FEMS Microbiol Ecol 2014; 89:495-515. [PMID: 24754794 DOI: 10.1111/1574-6941.12343] [Citation(s) in RCA: 136] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 04/07/2014] [Accepted: 04/08/2014] [Indexed: 11/29/2022] Open
Abstract
Marine microorganisms constitute the largest percentage of living biomass and serve as the major driving force behind nutrient and energy cycles. While viruses only comprise a small percentage of this biomass (i.e., 5%), they dominate in numerical abundance and genetic diversity. Through host infection and mortality, viruses affect microbial population dynamics, community composition, genetic evolution, and biogeochemical cycling. However, the field of marine viral ecology is currently limited by a lack of data regarding how different environmental factors regulate virus dynamics and host-virus interactions. The goal of the present minireview was to contribute to the evolution of marine viral ecology, through the assimilation of available data regarding the manner and degree to which environmental factors affect viral decay and infectivity as well as influence latent period and production. Considering the ecological importance of viruses in the marine ecosystem and the increasing pressure from anthropogenic activity and global climate change on marine systems, a synthesis of existing information provides a timely framework for future research initiatives in viral ecology.
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Affiliation(s)
- Kristina D A Mojica
- Department of Biological Oceanography, Royal Netherlands Institute for Sea Research (NIOZ), Den Burg, The Netherlands
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Chen Z, Lei X, Zhang B, Yang L, Zhang H, Zhang J, Li Y, Zheng W, Tian Y, Liu J, Zheng T. First report of Pseudobodo sp, a new pathogen for a potential energy-producing algae: Chlorella vulgaris cultures. PLoS One 2014; 9:e89571. [PMID: 24599263 PMCID: PMC3943784 DOI: 10.1371/journal.pone.0089571] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2013] [Accepted: 01/21/2014] [Indexed: 12/03/2022] Open
Abstract
Chlorella vulgaris, is a kind of single-celled green algae, which could serve as a potential source of food and energy because of its photosynthetic efficiency. In our study, a pathogenic organism targeting C. vulgaris was discovered. The algae-lytic activity relates to a fraction from lysates of infected C. vulgaris that was blocked upon filtration through a 3 µm filter. 18S rRNA gene sequence analysis revealed that it shared 99.0% homology with the protist Pseudobodo tremulans. Scanning electron microscope analysis showed that Pseudobodo sp. KD51 cells were approximately 4–5 µm long, biflagellate with an anterior collar around the anterior part of the cell in unstressed feeding cells. Besides the initial host, Pseudobodo sp. KD51 could also kill other algae, indicating its relatively wide predatory spectrum. Heat stability, pH and salinity tolerance experiments were conducted to understand their effects on its predatory activities, and the results showed that Pseudobodo sp. KD51 was heat-sensitive, and pH and salinity tolerant.
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Affiliation(s)
- Zhangran Chen
- State Key Laboratory for Marine Environmental Sciences and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, School of Life Sciences, Xiamen University, Xiamen, China
- ShenZhen Research Institute of Xiamen University, ShenZhen, China
| | - Xueqian Lei
- State Key Laboratory for Marine Environmental Sciences and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, School of Life Sciences, Xiamen University, Xiamen, China
| | - Bangzhou Zhang
- State Key Laboratory for Marine Environmental Sciences and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, School of Life Sciences, Xiamen University, Xiamen, China
| | - Luxi Yang
- State Key Laboratory for Marine Environmental Sciences and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, School of Life Sciences, Xiamen University, Xiamen, China
| | - Huajun Zhang
- State Key Laboratory for Marine Environmental Sciences and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, School of Life Sciences, Xiamen University, Xiamen, China
| | - Jingyan Zhang
- State Key Laboratory for Marine Environmental Sciences and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, School of Life Sciences, Xiamen University, Xiamen, China
| | - Yi Li
- State Key Laboratory for Marine Environmental Sciences and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, School of Life Sciences, Xiamen University, Xiamen, China
| | - Wei Zheng
- State Key Laboratory for Marine Environmental Sciences and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, School of Life Sciences, Xiamen University, Xiamen, China
| | - Yun Tian
- State Key Laboratory for Marine Environmental Sciences and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, School of Life Sciences, Xiamen University, Xiamen, China
| | - Jingwen Liu
- Bioengineering College of Jimei University, Xiamen, China
- * E-mail: (TZ); (JL)
| | - Tianling Zheng
- State Key Laboratory for Marine Environmental Sciences and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, School of Life Sciences, Xiamen University, Xiamen, China
- ShenZhen Research Institute of Xiamen University, ShenZhen, China
- * E-mail: (TZ); (JL)
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Kimura K, Tomaru Y. Isolation and characterization of a single-stranded DNA virus infecting the marine diatom Chaetoceros sp. strain SS628-11 isolated from western Japan. PLoS One 2013; 8:e82013. [PMID: 24358139 PMCID: PMC3866115 DOI: 10.1371/journal.pone.0082013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Accepted: 10/28/2013] [Indexed: 12/02/2022] Open
Abstract
Diatoms are significant organisms for primary production in the earth's aquatic environment. Hence, their dynamics are an important focus area in current studies. Viruses are a great concern as potential factors of diatom mortality, along with other physical, chemical, and biological factors. We isolated and characterized a new diatom virus (Csp07DNAV) that lyses the marine planktonic diatom Chaetoceros sp. strain SS628-11. This paper examines the physiological, morphological, and genomic characteristics of Csp07DNAV. The virus was isolated from a surface water sample that was collected at Hiroshima Bay, Japan. It was icosahedral, had a diameter of 34 nm, and accumulated in the nuclei of host cells. Rod-shaped virus particles also coexisted in the host nuclei. The latent period and burst size were estimated to be <12 h and 29 infectious units per host cell, respectively. Csp07DNAV had a closed circular single-stranded DNA genome (5,552 nucleotides), which included a double-stranded region and 3 open reading frames. The monophyly of Csp07DNAV and other Bacilladnavirus group single-stranded DNA viruses was supported by phylogenetic analysis that was based on the amino acid sequence of each virus protein. On the basis of these results, we considered Csp07DNAV to be a new member of the genus Bacilladnavirus.
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Affiliation(s)
- Kei Kimura
- National Research Institute of Fisheries and Environment of Inland Sea, Fisheries Research Agency, Hatsukaichi, Hiroshima, Japan
- Research Fellow of the Japan Society for the Promotion of Science, Tokyo, Japan
| | - Yuji Tomaru
- National Research Institute of Fisheries and Environment of Inland Sea, Fisheries Research Agency, Hatsukaichi, Hiroshima, Japan
- * E-mail:
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40
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Tomaru Y, Toyoda K, Suzuki H, Nagumo T, Kimura K, Takao Y. New single-stranded DNA virus with a unique genomic structure that infects marine diatom Chaetoceros setoensis. Sci Rep 2013; 3:3337. [PMID: 24275766 PMCID: PMC3840382 DOI: 10.1038/srep03337] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Accepted: 11/11/2013] [Indexed: 11/09/2022] Open
Abstract
Diatoms are among the most abundant organisms in nature; however, their relationships with single-stranded DNA (ssDNA) viruses have not yet been defined in detail. We report the isolation and characterisation of a virus (CsetDNAV) that lytically infects the bloom-forming diatom Chaetoceros setoensis. The virion is 33 nm in diameter and accumulates in the nucleus of its host. CsetDNAV harbours a covalently closed-circular ssDNA genome comprising 5836 nucleotides and eight different short-complementary fragments (67–145 nucleotides), which have not been reported in other diatom viruses. Phylogenetic analysis based on the putative replicase-related protein showed that CsetDNAV was not included in the monophyly of the recently established genus Bacilladnavirus. This discovery of CsetDNAV, which harbours a genome with a structure that is unique among known viruses that infect diatoms, suggests that other such undiscovered viruses possess diverse genomic architectures.
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Affiliation(s)
- Yuji Tomaru
- National Research Institute of Fisheries and Environment of Inland Sea, Fisheries Research Agency, 2-17-5 Maruishi, Hatsukaichi, Hiroshima 739-0452, Japan
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Abstract
Viruses are abundant in the ocean and a major driving force in plankton ecology and evolution. It has been assumed that most of the viruses in seawater contain DNA and infect bacteria, but RNA-containing viruses in the ocean, which almost exclusively infect eukaryotes, have never been quantified. We compared the total mass of RNA and DNA in the viral fraction harvested from seawater and using data on the mass of nucleic acid per RNA- or DNA-containing virion, estimated the abundances of each. Our data suggest that the abundance of RNA viruses rivaled or exceeded that of DNA viruses in samples of coastal seawater. The dominant RNA viruses in the samples were marine picorna-like viruses, which have small genomes and are at or below the detection limit of common fluorescence-based counting methods. If our results are typical, this means that counts of viruses and the rate measurements that depend on them, such as viral production, are significantly underestimated by current practices. As these RNA viruses infect eukaryotes, our data imply that protists contribute more to marine viral dynamics than one might expect based on their relatively low abundance. This conclusion is a departure from the prevailing view of viruses in the ocean, but is consistent with earlier theoretical predictions.
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42
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Wada K, Kimura K, Hasegawa A, Fukuyama K, Nagasaki K. Establishment of a bacterial expression system and immunoassay platform for the major capsid protein of HcRNAV, a dinoflagellate-infecting RNA virus. Microbes Environ 2012; 27:483-9. [PMID: 23047150 PMCID: PMC4103558 DOI: 10.1264/jsme2.me12046] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
HcRNAV is a small icosahedral virus that infects the shellfish-killing marine dinoflagellate Heterocapsa circularisquama, which harbors a dicistronic linear single-stranded RNA (ssRNA) genome ca. 4.4 kb in length. Its major capsid protein (MCP) gene sequence is not expressed by various strains of Escherichia coli, possibly because of a codon usage problem. To solve this problem, a chemically modified (i.e., de novo synthesized) gene was designed and cloned into the pCold-GST expression vector, and transformed into E. coli strain C41 (DE3), in which codon usage was universally optimized to efficiently express the polypeptide having the viral MCP amino acid sequence. The bacterially expressed protein, which was purified after a procedure involving denaturation and refolding, successfully formed virus-like particles that significantly resembled native HcRNAV particles. The purified, denatured protein was used as an antigen to immunize rabbits, and the resulting antiserum was shown to be strongly reactive to not only the bacterially expressed recombinant protein, but also to native HcRNAV MCP by Western blotting and dot immunoassays, respectively. These results indicate that an antiserum recognizing native HcRNAV MCP was successfully obtained using bacterially expressed HcRNAV MCP as the antigen.
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Affiliation(s)
- Kei Wada
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Osaka 560–0043, Japan
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43
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Abstract
Diatoms are considered the most successful and widespread group of photosynthetic eukaryotes. Their contribution to primary production is remarkably significant to the earth's ecosystems. Diatoms are composed of two orders: Centrales and Pennales. Thus far, viruses infecting centric diatom species have been isolated and characterized; however, viruses infecting pennates have not been reported. Here, we describe the first isolations and preliminary characterizations of two distinct pennate diatom viruses, AglaRNAV (31 nm in diameter, accumulates in the host cytoplasm) and TnitDNAV (35 nm in diameter, accumulates in the host nuclei) infecting Asterionellopsis glacialis and Thalassionema nitzschioides, respectively. Their genomes contain a single-stranded RNA of approximately 9.5 kb, and a closed, circular single-stranded DNA of approximately 5.5 kb harboring a partially double-stranded region, respectively. Further analysis of these viruses may elucidate many aspects of diatom host-virus relationships.
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Boros Á, Pankovics P, Simmonds P, Reuter G. Novel positive-sense, single-stranded RNA (+ssRNA) virus with di-cistronic genome from intestinal content of freshwater carp (Cyprinus carpio). PLoS One 2011; 6:e29145. [PMID: 22195010 PMCID: PMC3241695 DOI: 10.1371/journal.pone.0029145] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Accepted: 11/21/2011] [Indexed: 11/18/2022] Open
Abstract
A novel positive-sense, single-stranded RNA (+ssRNA) virus (Halastavi árva RNA virus, HalV; JN000306) with di-cistronic genome organization was serendipitously identified in intestinal contents of freshwater carps (Cyprinus carpio) fished by line-fishing from fishpond "Lőrinte halastó" located in Veszprém County, Hungary. The complete nucleotide (nt) sequence of the genomic RNA is 9565 nt in length and contains two long--non-in-frame--open reading frames (ORFs), which are separated by an intergenic region. The ORF1 (replicase) is preceded by an untranslated sequence of 827 nt, while an untranslated region of 139 nt follows the ORF2 (capsid proteins). The deduced amino acid (aa) sequences of the ORFs showed only low (less than 32%) and partial similarity to the non-structural (2C-like helicase, 3C-like cystein protease and 3D-like RNA dependent RNA polymerase) and structural proteins (VP2/VP4/VP3) of virus families in Picornavirales especially to members of the viruses with dicistronic genome. Halastavi árva RNA virus is present in intestinal contents of omnivorous freshwater carps but the origin and the host species of this virus remains unknown. The unique viral sequence and the actual position indicate that Halastavi árva RNA virus seems to be the first member of a new di-cistronic ssRNA virus. Further studies are required to investigate the specific host species (and spectrum), ecology and role of Halastavi árva RNA virus in the nature.
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Affiliation(s)
- Ákos Boros
- Regional Laboratory of Virology, National Reference Laboratory of Gastroenteric Viruses, ÁNTSZ Regional Institute of State Public Health Service, Pécs, Hungary
| | - Péter Pankovics
- Regional Laboratory of Virology, National Reference Laboratory of Gastroenteric Viruses, ÁNTSZ Regional Institute of State Public Health Service, Pécs, Hungary
| | - Peter Simmonds
- University of Edinburgh, Edinburgh, Scotland, United Kingdom
| | - Gábor Reuter
- Regional Laboratory of Virology, National Reference Laboratory of Gastroenteric Viruses, ÁNTSZ Regional Institute of State Public Health Service, Pécs, Hungary
- * E-mail:
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45
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A chemical arms race at sea mediates algal host–virus interactions. Curr Opin Microbiol 2011; 14:449-57. [PMID: 21816665 DOI: 10.1016/j.mib.2011.07.013] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Accepted: 07/05/2011] [Indexed: 01/28/2023]
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46
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Culley AI. Virophages to viromes: a report from the frontier of viral oceanography. Curr Opin Virol 2011; 1:52-7. [PMID: 22440567 DOI: 10.1016/j.coviro.2011.05.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Revised: 05/16/2011] [Accepted: 05/16/2011] [Indexed: 12/26/2022]
Abstract
The investigation of marine viruses has advanced our understanding of ecology, evolution, microbiology, oceanography and virology. Significant findings discussed in this review include the discovery of giant viruses that have genome sizes and metabolic capabilities that distort the line between virus and cell, viruses that participate in photosynthesis and apoptosis, the detection of communities of viruses of all genomic compositions and the preeminence of viruses in the evolution of marine microbes. Although we have made great progress, we have yet to synthesize the rich archive of viral genomic data with oceanographic processes. The development of cutting edge methods such as single virus genomics now provide a toolset to better integrate viruses into the ecology of the ocean.
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Affiliation(s)
- Alexander I Culley
- Center for Microbial Oceanography: Research and Education, Department of Oceanography, University of Hawaii at Manoa, CMORE Hale, Honolulu, HI 96822, United States.
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47
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Isolation and characterization of a single-stranded DNA virus infecting Chaetoceros lorenzianus Grunow. Appl Environ Microbiol 2011; 77:5285-93. [PMID: 21666026 DOI: 10.1128/aem.00202-11] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Diatoms are one of the most significant primary producers in the ocean, and the importance of viruses as a potential source of mortality for diatoms has recently been recognized. Thus far, eight different diatom viruses infecting the genera Rhizosolenia and Chaetoceros have been isolated and characterized to different extents. We report the isolation of a novel diatom virus (ClorDNAV), which causes the lysis of the bloom-forming species Chaetoceros lorenzianus, and show its physiological, morphological, and genomic characteristics. The free virion was estimated to be ∼34 nm in diameter. The arrangement of virus particles appearing in cross-section was basically a random aggregation in the nucleus. Occasionally, distinctive formations such as a ring-like array composed of 9 or 10 spherical virions or a centipede-like array composed of rod-shaped particles were also observed. The latent period and the burst size were estimated to be <48 h and 2.2 × 10(4) infectious units per host cell, respectively. ClorDNAV harbors a covalently closed circular single-stranded DNA (ssDNA) genome (5,813 nucleotides [nt]) that includes a partially double-stranded DNA region (979 nt). At least three major open reading frames were identified; one showed a high similarity to putative replicase-related proteins of the other ssDNA diatom viruses, Chaetoceros salsugineum DNA virus (previously reported as CsNIV) and Chaetoceros tenuissimus DNA virus. ClorDNAV is the third member of the closed circular ssDNA diatom virus group, the genus Bacilladnavirus.
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48
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Yoon HS, Price DC, Stepanauskas R, Rajah VD, Sieracki ME, Wilson WH, Yang EC, Duffy S, Bhattacharya D. Single-cell genomics reveals organismal interactions in uncultivated marine protists. Science 2011; 332:714-7. [PMID: 21551060 DOI: 10.1126/science.1203163] [Citation(s) in RCA: 246] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Whole-genome shotgun sequence data from three individual cells isolated from seawater, followed by analysis of ribosomal DNA, indicated that the cells represented three divergent clades of picobiliphytes. In contrast with the recent description of this phylum, we found no evidence of plastid DNA nor of nuclear-encoded plastid-targeted proteins, which suggests that these picobiliphytes are heterotrophs. Genome data from one cell were dominated by sequences from a widespread single-stranded DNA virus. This virus was absent from the other two cells, both of which contained non-eukaryote DNA derived from marine Bacteroidetes and large DNA viruses. By using shotgun sequencing of uncultured marine picobiliphytes, we revealed the distinct interactions of individual cells.
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Affiliation(s)
- Hwan Su Yoon
- Bigelow Laboratory for Ocean Sciences, West Boothbay Harbor, ME 04575, USA
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49
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Dittmar T, Zänker KS. Horizontal gene transfers with or without cell fusions in all categories of the living matter. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 714:5-89. [PMID: 21506007 PMCID: PMC7120942 DOI: 10.1007/978-94-007-0782-5_2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
This article reviews the history of widespread exchanges of genetic segments initiated over 3 billion years ago, to be part of their life style, by sphero-protoplastic cells, the ancestors of archaea, prokaryota, and eukaryota. These primordial cells shared a hostile anaerobic and overheated environment and competed for survival. "Coexist with, or subdue and conquer, expropriate its most useful possessions, or symbiose with it, your competitor" remain cellular life's basic rules. This author emphasizes the role of viruses, both in mediating cell fusions, such as the formation of the first eukaryotic cell(s) from a united crenarchaeon and prokaryota, and the transfer of host cell genes integrated into viral (phages) genomes. After rising above the Darwinian threshold, rigid rules of speciation and vertical inheritance in the three domains of life were established, but horizontal gene transfers with or without cell fusions were never abolished. The author proves with extensive, yet highly selective documentation, that not only unicellular microorganisms, but the most complex multicellular entities of the highest ranks resort to, and practice, cell fusions, and donate and accept horizontally (laterally) transferred genes. Cell fusions and horizontally exchanged genetic materials remain the fundamental attributes and inherent characteristics of the living matter, whether occurring accidentally or sought after intentionally. These events occur to cells stagnating for some 3 milliard years at a lower yet amazingly sophisticated level of evolution, and to cells achieving the highest degree of differentiation, and thus functioning in dependence on the support of a most advanced multicellular host, like those of the human brain. No living cell is completely exempt from gene drains or gene insertions.
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Affiliation(s)
- Thomas Dittmar
- Inst. Immunologie, Universität Witten/Herdecke, Stockumer Str. 10, Witten, 58448 Germany
| | - Kurt S. Zänker
- Institute of Immunologie, University of Witten/Herdecke, Stockumer Str. 10, Witten, 58448 Germany
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