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Perini L, Sipes K, Zervas A, Bellas C, Lutz S, Moniruzzaman M, Mourot R, Benning LG, Tranter M, Anesio AM. Giant viral signatures on the Greenland ice sheet. MICROBIOME 2024; 12:91. [PMID: 38760842 PMCID: PMC11100222 DOI: 10.1186/s40168-024-01796-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 03/18/2024] [Indexed: 05/19/2024]
Abstract
BACKGROUND Dark pigmented snow and glacier ice algae on glaciers and ice sheets contribute to accelerating melt. The biological controls on these algae, particularly the role of viruses, remain poorly understood. Giant viruses, classified under the nucleocytoplasmic large DNA viruses (NCLDV) supergroup (phylum Nucleocytoviricota), are diverse and globally distributed. NCLDVs are known to infect eukaryotic cells in marine and freshwater environments, providing a biological control on the algal population in these ecosystems. However, there is very limited information on the diversity and ecosystem function of NCLDVs in terrestrial icy habitats. RESULTS In this study, we investigate for the first time giant viruses and their host connections on ice and snow habitats, such as cryoconite, dark ice, ice core, red and green snow, and genomic assemblies of five cultivated Chlorophyta snow algae. Giant virus marker genes were present in almost all samples; the highest abundances were recovered from red snow and the snow algae genomic assemblies, followed by green snow and dark ice. The variety of active algae and protists in these GrIS habitats containing NCLDV marker genes suggests that infection can occur on a range of eukaryotic hosts. Metagenomic data from red and green snow contained evidence of giant virus metagenome-assembled genomes from the orders Imitervirales, Asfuvirales, and Algavirales. CONCLUSION Our study highlights NCLDV family signatures in snow and ice samples from the Greenland ice sheet. Giant virus metagenome-assembled genomes (GVMAGs) were found in red snow samples, and related NCLDV marker genes were identified for the first time in snow algal culture genomic assemblies; implying a relationship between the NCLDVs and snow algae. Metatranscriptomic viral genes also aligned with metagenomic sequences, suggesting that NCLDVs are an active component of the microbial community and are potential "top-down" controls of the eukaryotic algal and protistan members. This study reveals the unprecedented presence of a diverse community of NCLDVs in a variety of glacial habitats dominated by algae.
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Affiliation(s)
- Laura Perini
- Department of Environmental Science, Aarhus University, Roskilde, 4000, Denmark.
| | - Katie Sipes
- Department of Environmental Science, Aarhus University, Roskilde, 4000, Denmark
| | - Athanasios Zervas
- Department of Environmental Science, Aarhus University, Roskilde, 4000, Denmark
| | | | - Stefanie Lutz
- Department of Agroecology and Environment, Plant-Soil Interactions, Agroscope, Zurich, Switzerland
- German Research Centre for Geosciences, Helmholtz Centre Potsdam, Telegrafenberg, Potsdam, 14473, Germany
| | - Mohammad Moniruzzaman
- Department of Biological Sciences, Rosenstiel School of Marine, Atmospheric and Earth Science, University of Miami, Coral Gables, FL, USA
| | - Rey Mourot
- German Research Centre for Geosciences, Helmholtz Centre Potsdam, Telegrafenberg, Potsdam, 14473, Germany
- Department of Earth Sciences, Freie Universität Berlin, Berlin, 12249, Germany
| | - Liane G Benning
- German Research Centre for Geosciences, Helmholtz Centre Potsdam, Telegrafenberg, Potsdam, 14473, Germany
- Department of Earth Sciences, Freie Universität Berlin, Berlin, 12249, Germany
| | - Martyn Tranter
- Department of Environmental Science, Aarhus University, Roskilde, 4000, Denmark
| | - Alexandre M Anesio
- Department of Environmental Science, Aarhus University, Roskilde, 4000, Denmark
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Vieira HH, Bulzu PA, Kasalický V, Haber M, Znachor P, Piwosz K, Ghai R. Isolation of a widespread giant virus implicated in cryptophyte bloom collapse. THE ISME JOURNAL 2024; 18:wrae029. [PMID: 38401169 PMCID: PMC10960955 DOI: 10.1093/ismejo/wrae029] [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: 11/16/2023] [Revised: 01/29/2024] [Accepted: 02/22/2024] [Indexed: 02/26/2024]
Abstract
Photosynthetic cryptophytes are ubiquitous protists that are major participants in the freshwater phytoplankton bloom at the onset of spring. Mortality due to change in environmental conditions and grazing have been recognized as key factors contributing to bloom collapse. In contrast, the role of viral outbreaks as factors terminating phytoplankton blooms remains unknown from freshwaters. Here, we isolated and characterized a cryptophyte virus contributing to the annual collapse of a natural cryptophyte spring bloom population. This viral isolate is also representative for a clade of abundant giant viruses (phylum Nucleocytoviricota) found in freshwaters all over the world.
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Affiliation(s)
- Helena H Vieira
- Department of Aquatic Microbial Ecology, Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, 37005 České Budějovice, Czech Republic
| | - Paul-Adrian Bulzu
- Department of Aquatic Microbial Ecology, Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, 37005 České Budějovice, Czech Republic
| | - Vojtěch Kasalický
- Department of Aquatic Microbial Ecology, Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, 37005 České Budějovice, Czech Republic
| | - Markus Haber
- Department of Aquatic Microbial Ecology, Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, 37005 České Budějovice, Czech Republic
| | - Petr Znachor
- Department of Aquatic Microbial Ecology, Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, 37005 České Budějovice, Czech Republic
| | - Kasia Piwosz
- Department of Fisheries Oceanography and Marine Ecology, National Marine Fisheries Research Institute, 81-332 Gdynia, Poland
| | - Rohit Ghai
- Department of Aquatic Microbial Ecology, Institute of Hydrobiology, Biology Centre of the Czech Academy of Sciences, 37005 České Budějovice, Czech Republic
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Truchon AR, Chase EE, Gann ER, Moniruzzaman M, Creasey BA, Aylward FO, Xiao C, Gobler CJ, Wilhelm SW. Kratosvirus quantuckense: the history and novelty of an algal bloom disrupting virus and a model for giant virus research. Front Microbiol 2023; 14:1284617. [PMID: 38098665 PMCID: PMC10720644 DOI: 10.3389/fmicb.2023.1284617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 10/30/2023] [Indexed: 12/17/2023] Open
Abstract
Since the discovery of the first "giant virus," particular attention has been paid toward isolating and culturing these large DNA viruses through Acanthamoeba spp. bait systems. While this method has allowed for the discovery of plenty novel viruses in the Nucleocytoviricota, environmental -omics-based analyses have shown that there is a wealth of diversity among this phylum, particularly in marine datasets. The prevalence of these viruses in metatranscriptomes points toward their ecological importance in nutrient turnover in our oceans and as such, in depth study into non-amoebal Nucleocytoviricota should be considered a focal point in viral ecology. In this review, we report on Kratosvirus quantuckense (née Aureococcus anophagefferens Virus), an algae-infecting virus of the Imitervirales. Current systems for study in the Nucleocytoviricota differ significantly from this virus and its relatives, and a litany of trade-offs within physiology, coding potential, and ecology compared to these other viruses reveal the importance of K. quantuckense. Herein, we review the research that has been performed on this virus as well as its potential as a model system for algal-virus interactions.
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Affiliation(s)
- Alexander R Truchon
- Department of Microbiology, University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Emily E Chase
- Department of Microbiology, University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Eric R Gann
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, United States
- Department of Surgery, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
- Surgical Critical Care Initiative (SC2i), Department of Surgery, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Mohammad Moniruzzaman
- Department of Marine Biology and Ecology, University of Miami, Miami, FL, United States
| | - Brooke A Creasey
- Department of Microbiology, University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Frank O Aylward
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, United States
| | - Chuan Xiao
- Department of Chemistry and Biochemistry, The University of Texas at El Paso, El Paso, TX, United States
| | | | - Steven W Wilhelm
- Department of Microbiology, University of Tennessee, Knoxville, Knoxville, TN, United States
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Hikida H, Okazaki Y, Zhang R, Nguyen TT, Ogata H. A rapid genome-wide analysis of isolated giant viruses using MinION sequencing. Environ Microbiol 2023; 25:2621-2635. [PMID: 37543720 DOI: 10.1111/1462-2920.16476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 07/20/2023] [Indexed: 08/07/2023]
Abstract
Following the discovery of Acanthamoeba polyphaga mimivirus, diverse giant viruses have been isolated. However, only a small fraction of these isolates have been completely sequenced, limiting our understanding of the genomic diversity of giant viruses. MinION is a portable and low-cost long-read sequencer that can be readily used in a laboratory. Although MinION provides highly error-prone reads that require correction through additional short-read sequencing, recent studies assembled high-quality microbial genomes only using MinION sequencing. Here, we evaluated the accuracy of MinION-only genome assemblies for giant viruses by re-sequencing a prototype marseillevirus. Assembled genomes presented over 99.98% identity to the reference genome with a few gaps, demonstrating a high accuracy of the MinION-only assembly. As a proof of concept, we de novo assembled five newly isolated viruses. Average nucleotide identities to their closest known relatives suggest that the isolates represent new species of marseillevirus, pithovirus and mimivirus. The assembly of subsampled reads demonstrated that their taxonomy and genomic composition could be analysed at the 50× sequencing coverage. We also identified a pithovirus gene whose homologues were detected only in metagenome-derived relatives. Collectively, we propose that MinION-only assembly is an effective approach to rapidly perform a genome-wide analysis of isolated giant viruses.
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Affiliation(s)
- Hiroyuki Hikida
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Kyoto, Japan
| | - Yusuke Okazaki
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Kyoto, Japan
| | - Ruixuan Zhang
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Kyoto, Japan
| | - Thi Tuyen Nguyen
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Kyoto, Japan
| | - Hiroyuki Ogata
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Kyoto, Japan
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Aylward FO, Abrahão JS, Brussaard CPD, Fischer MG, Moniruzzaman M, Ogata H, Suttle CA. Taxonomic update for giant viruses in the order Imitervirales (phylum Nucleocytoviricota). Arch Virol 2023; 168:283. [PMID: 37904060 DOI: 10.1007/s00705-023-05906-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2023]
Abstract
Large DNA viruses in the phylum Nucleocytoviricota, sometimes referred to as "giant viruses" owing to their large genomes and virions, have been the subject of burgeoning interest over the last decade. Here, we describe recently adopted taxonomic updates for giant viruses within the order Imitervirales. The families Allomimiviridae, Mesomimiviridae, and Schizomimiviridae have been created to accommodate the increasing diversity of mimivirus relatives that have sometimes been referred to in the literature as "extended Mimiviridae". In addition, the subfamilies Aliimimivirinae, Megamimivirinae, and Klosneuvirinae have been established to refer to subgroups of the Mimiviridae. Binomial names have also been adopted for all recognized species in the order. For example, Acanthamoeba polyphaga mimivirus is now classified in the species Mimivirus bradfordmassiliense.
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Affiliation(s)
- Frank O Aylward
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, 24061, USA.
- Center for Emerging, Zoonotic, and Arthropod-Borne Pathogens, Virginia Tech, Blacksburg, VA, USA.
| | - Jonatas S Abrahão
- Laboratório de Vírus, Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Corina P D Brussaard
- Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, Texel, The Netherlands
- Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam, Amsterdam, The Netherlands
| | - Matthias G Fischer
- Max Planck Institute for Medical Research, Department of Biomolecular Mechanisms, Heidelberg, Germany
| | - Mohammad Moniruzzaman
- Department of Marine Biology and Ecology, Rosenstiel School of Marine, Atmospheric, and Earth Science, University of Miami, Coral Gables, FL, 33149, USA
| | - Hiroyuki Ogata
- Bioinformatics Center, Institute for Chemical Research, Kyoto University, Uji, 611-0011, Japan
| | - Curtis A Suttle
- Department of Earth, Ocean, and Atmospheric Sciences, University of British Columbia, Vancouver, BC, Canada
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
- Department of Botany, University of British Columbia, Vancouver, BC, Canada
- Institute for the Oceans and Fisheries, University of British Columbia, Vancouver, BC, Canada
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6
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Moniruzzaman M, Erazo Garcia MP, Farzad R, Ha AD, Jivaji A, Karki S, Sheyn U, Stanton J, Minch B, Stephens D, Hancks DC, Rodrigues RAL, Abrahao JS, Vardi A, Aylward FO. Virologs, viral mimicry, and virocell metabolism: the expanding scale of cellular functions encoded in the complex genomes of giant viruses. FEMS Microbiol Rev 2023; 47:fuad053. [PMID: 37740576 PMCID: PMC10583209 DOI: 10.1093/femsre/fuad053] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 08/29/2023] [Accepted: 09/21/2023] [Indexed: 09/24/2023] Open
Abstract
The phylum Nucleocytoviricota includes the largest and most complex viruses known. These "giant viruses" have a long evolutionary history that dates back to the early diversification of eukaryotes, and over time they have evolved elaborate strategies for manipulating the physiology of their hosts during infection. One of the most captivating of these mechanisms involves the use of genes acquired from the host-referred to here as viral homologs or "virologs"-as a means of promoting viral propagation. The best-known examples of these are involved in mimicry, in which viral machinery "imitates" immunomodulatory elements in the vertebrate defense system. But recent findings have highlighted a vast and rapidly expanding array of other virologs that include many genes not typically found in viruses, such as those involved in translation, central carbon metabolism, cytoskeletal structure, nutrient transport, vesicular trafficking, and light harvesting. Unraveling the roles of virologs during infection as well as the evolutionary pathways through which complex functional repertoires are acquired by viruses are important frontiers at the forefront of giant virus research.
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Affiliation(s)
- Mohammad Moniruzzaman
- Rosenstiel School of Marine Atmospheric, and Earth Science, University of Miami, Coral Gables, FL 33149, United States
| | - Maria Paula Erazo Garcia
- Department of Biological Sciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA 24061, United States
| | - Roxanna Farzad
- Department of Biological Sciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA 24061, United States
| | - Anh D Ha
- Department of Biological Sciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA 24061, United States
| | - Abdeali Jivaji
- Department of Biological Sciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA 24061, United States
| | - Sangita Karki
- Department of Biological Sciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA 24061, United States
| | - Uri Sheyn
- Department of Biological Sciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA 24061, United States
| | - Joshua Stanton
- Department of Biological Sciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA 24061, United States
| | - Benjamin Minch
- Rosenstiel School of Marine Atmospheric, and Earth Science, University of Miami, Coral Gables, FL 33149, United States
| | - Danae Stephens
- Rosenstiel School of Marine Atmospheric, and Earth Science, University of Miami, Coral Gables, FL 33149, United States
| | - Dustin C Hancks
- Department of Immunology, University of Texas Southwestern Medical Center, 6000 Harry Hines Blvd, Dallas, TX, United States
| | - Rodrigo A L Rodrigues
- Laboratório de Vírus, Departamento de Microbiologia, Universidade Federal de Minas Gerais, Belo Horizonte 31270-901, MG, Brazil
| | - Jonatas S Abrahao
- Laboratório de Vírus, Departamento de Microbiologia, Universidade Federal de Minas Gerais, Belo Horizonte 31270-901, MG, Brazil
| | - Assaf Vardi
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, 7610001 Rehovot, Israel
| | - Frank O Aylward
- Department of Biological Sciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA 24061, United States
- Center for Emerging, Zoonotic, and Arthropod-Borne Infectious Disease, Virginia Tech, Blacksburg, VA 24061, United States
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7
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Ha AD, Moniruzzaman M, Aylward FO. Assessing the biogeography of marine giant viruses in four oceanic transects. ISME COMMUNICATIONS 2023; 3:43. [PMID: 37120676 PMCID: PMC10148842 DOI: 10.1038/s43705-023-00252-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 04/11/2023] [Accepted: 04/19/2023] [Indexed: 05/01/2023]
Abstract
Viruses of the phylum Nucleocytoviricota are ubiquitous in ocean waters and play important roles in shaping the dynamics of marine ecosystems. In this study, we leveraged the bioGEOTRACES metagenomic dataset collected across the Atlantic and Pacific Oceans to investigate the biogeography of these viruses in marine environments. We identified 330 viral genomes, including 212 in the order Imitervirales and 54 in the order Algavirales. We found that most viruses appeared to be prevalent in shallow waters (<150 m), and that viruses of the Mesomimiviridae (Imitervirales) and Prasinoviridae (Algavirales) are by far the most abundant and diverse groups in our survey. Five mesomimiviruses and one prasinovirus are particularly widespread in oligotrophic waters; annotation of these genomes revealed common stress response systems, photosynthesis-associated genes, and oxidative stress modulation genes that may be key to their broad distribution in the pelagic ocean. We identified a latitudinal pattern in viral diversity in one cruise that traversed the North and South Atlantic Ocean, with viral diversity peaking at high latitudes of the northern hemisphere. Community analyses revealed three distinct Nucleocytoviricota communities across latitudes, categorized by latitudinal distance towards the equator. Our results contribute to the understanding of the biogeography of these viruses in marine systems.
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Affiliation(s)
- Anh D Ha
- Department of Biological Sciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, USA
| | - Mohammad Moniruzzaman
- Department of Marine Biology and Ecology, Rosenstiel School of Marine, Atmospheric, and Earth Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL, 33149, USA
| | - Frank O Aylward
- Department of Biological Sciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, USA.
- Center for Emerging, Zoonotic, and Arthropod-Borne Infectious Disease, Virginia Tech, Blacksburg, VA, 24061, USA.
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8
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Giant Virus Infection Signatures Are Modulated by Euphotic Zone Depth Strata and Iron Regimes of the Subantarctic Southern Ocean. mSystems 2023; 8:e0126022. [PMID: 36794943 PMCID: PMC10134803 DOI: 10.1128/msystems.01260-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
Viruses can alter the abundance, evolution, and metabolism of microorganisms in the ocean, playing a key role in water column biogeochemistry and global carbon cycles. Large efforts to measure the contribution of eukaryotic microorganisms (e.g., protists) to the marine food web have been made, yet the in situ activities of the ecologically relevant viruses that infect these organisms are not well characterized. Viruses within the phylum Nucleocytoviricota ("giant viruses") are known to infect a diverse range of ecologically relevant marine protists, yet how these viruses are influenced by environmental conditions remains under-characterized. By employing metatranscriptomic analyses of in situ microbial communities along a temporal and depth-resolved gradient, we describe the diversity of giant viruses at the Southern Ocean Time Series (SOTS), a site within the subpolar Southern Ocean. Using a phylogeny-guided taxonomic assessment of detected giant virus genomes and metagenome-assembled genomes, we observed depth-dependent structuring of divergent giant virus families mirroring dynamic physicochemical gradients in the stratified euphotic zone. Analyses of transcribed metabolic genes from giant viruses suggest viral metabolic reprogramming of hosts from the surface to a 200-m depth. Lastly, using on-deck incubations reflecting a gradient of iron availability, we show that modulating iron regimes influences the activity of giant viruses in the field. Specifically, we show enhanced infection signatures of giant viruses under both iron-replete and iron-limited conditions. Collectively, these results expand our understanding of how the water column's vertical biogeography and chemical surroundings affect an important group of viruses within the Southern Ocean. IMPORTANCE The biology and ecology of marine microbial eukaryotes is known to be constrained by oceanic conditions. In contrast, how viruses that infect this important group of organisms respond to environmental change is less well known, despite viruses being recognized as key microbial community members. Here, we address this gap in our understanding by characterizing the diversity and activity of "giant" viruses within an important region in the sub-Antarctic Southern Ocean. Giant viruses are double-stranded DNA (dsDNA) viruses of the phylum Nucleocytoviricota and are known to infect a wide range of eukaryotic hosts. By employing a metatranscriptomics approach using both in situ samples and microcosm manipulations, we illuminated both the vertical biogeography and how changing iron availability affects this primarily uncultivated group of protist-infecting viruses. These results serve as a foundation for our understanding of how the open ocean water column structures the viral community, which can be used to guide models of the viral impact on marine and global biogeochemical cycling.
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Ha AD, Moniruzzaman M, Aylward FO. Assessing the biogeography of marine giant viruses in four oceanic transects. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.30.526306. [PMID: 36778472 PMCID: PMC9915497 DOI: 10.1101/2023.01.30.526306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Viruses of the phylum Nucleocytoviricota are ubiquitous in ocean waters and play important roles in shaping the dynamics of marine ecosystems. In this study, we leveraged the bioGEOTRACES metagenomic dataset collected across the Atlantic and Pacific Oceans to investigate the biogeography of these viruses in marine environments. We identified 330 viral genomes, including 212 in the order Imitervirales and 54 in the order Algavirales . We found that most viruses appeared to be prevalent in shallow waters (<150 meters), and that viruses of the Mesomimiviridae ( Imitervirales ) and Prasinoviridae ( Algavirales ) are by far the most abundant and diverse groups in our survey. Five mesomimiviruses and one prasinovirus are particularly widespread in oligotrophic waters; annotation of these genomes revealed common stress response systems, photosynthesis-associated genes, and oxidative stress modulation that may be key to their broad distribution in the pelagic ocean. We identified a latitudinal pattern in viral diversity in one cruise that traversed the North and South Atlantic Ocean, with viral diversity peaking at high latitudes of the northern hemisphere. Community analyses revealed three distinct Nucleocytoviricota communities across latitudes, categorized by latitudinal distance towards the equator. Our results contribute to the understanding of the biogeography of these viruses in marine systems.
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Affiliation(s)
- Anh D. Ha
- Department of Biological Sciences, Virginia Tech, Blacksburg VA, 24061
| | - Mohammad Moniruzzaman
- Rosenstiel School of Marine Atmospheric, and Earth Science, University of Miami, Coral Gables FL 33149
| | - Frank O. Aylward
- Department of Biological Sciences, Virginia Tech, Blacksburg VA, 24061
- Center for Emerging, Zoonotic, and Arthropod-Borne Infectious Disease, Virginia Tech, Blacksburg VA, 24061
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Zhao J, Wang Z, Li C, Shi T, Liang Y, Jiao N, Zhang Y. Significant Differences in Planktonic Virus Communities Between "Cellular Fraction" (0.22 ~ 3.0 µm) and "Viral Fraction" (< 0.22 μm) in the Ocean. MICROBIAL ECOLOGY 2022:10.1007/s00248-022-02167-6. [PMID: 36585490 DOI: 10.1007/s00248-022-02167-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Accepted: 12/26/2022] [Indexed: 06/17/2023]
Abstract
Compared to free-living viruses (< 0.22 m) in the ocean, planktonic viruses in the "cellular fraction" (0.22 ~ 3.0 μm) are now far less well understood, and the differences between them remain largely unexplored. Here, we revealed that even in the same seawater samples, the "cellular fraction" comprised significantly distinct virus communities from the free virioplankton, with only 13.87% overlap in viral contigs at the species level. Compared to the viral genomes deposited in NCBI RefSeq database, 99% of the assembled viral genomes in the "cellular fraction" represented novel genera. Notably, the assembled (near-) complete viral genomes within the "cellular fraction" were significantly larger than that in the "viral fraction," and the "cellular fraction" contained three times more species of giant viruses or jumbo phages with genomes > 200 kb than the "viral fraction." The longest complete genomes of jumbo phage (~ 252 kb) and giant virus (~ 716 kb) were both detected only in the "cellular fraction." Moreover, a relatively higher proportion of proviruses were predicted within the "cellular fraction" than "viral fraction." Besides the substantial divergence in viral community structure, the different fractions also contained their unique viral auxiliary metabolic genes; e.g., those potentially participating in inorganic carbon fixation in deep sea were detected only in the "cellular-fraction" viromes. In addition, there was a considerable divergence in the community structure of both "cellular fraction" and "viral fraction" viromes between the surface and deep-sea habitats, suggesting that they might have similar environmental adaptation properties. The findings deepen our understanding of the complexity of viral community structure and function in the ocean.
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Affiliation(s)
- Jiulong Zhao
- Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zengmeng Wang
- Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Chengcheng Li
- Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
| | - Tongmei Shi
- Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yantao Liang
- Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
| | - Nianzhi Jiao
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, 361005, China
| | - Yongyu Zhang
- Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
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11
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Bachy C, Baudoux AC. [Diversity and ecological importance of viruses in the marine environment]. Med Sci (Paris) 2022; 38:1008-1015. [PMID: 36692280 DOI: 10.1051/medsci/2022165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The ocean is the largest reservoir of viruses on the planet with estimates of up to several billions per liter. These viruses represent a major driving force not only for the evolution and for structuring the microbial world, but also for the functioning and the balance of marine ecosystems. With the advances in high throughput sequencing techniques, we are beginning to uncover the diversity and the complexity of this marine virosphere. This review synthesizes milestones in the field of marine viral ecology, including the diversity of these fascinating microorganisms, their impact on microbial mortality and cycling of nutrients and energy in the ocean.
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Affiliation(s)
- Charles Bachy
- Sorbonne Université, CNRS, FR2424, Station biologique de Roscoff, Roscoff, 29680, France
| | - Anne-Claire Baudoux
- Sorbonne université, CNRS, Station biologique de Roscoff, Laboratoire adaptation et diversité en milieu marin, UMR7144, Roscoff, 29680, France
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12
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Giant Viruses as a Source of Novel Enzymes for Biotechnological Application. Pathogens 2022; 11:pathogens11121453. [PMID: 36558786 PMCID: PMC9787589 DOI: 10.3390/pathogens11121453] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 11/24/2022] [Accepted: 11/28/2022] [Indexed: 12/05/2022] Open
Abstract
The global demand for industrial enzymes has been increasing in recent years, and the search for new sources of these biological products is intense, especially in microorganisms. Most known viruses have limited genetic machinery and, thus, have been overlooked by the enzyme industry for years. However, a peculiar group of viruses breaks this paradigm. Giant viruses of the phylum Nucleocytoviricota infect protists (i.e., algae and amoebae) and have complex genomes, reaching up to 2.7 Mb in length and encoding hundreds of genes. Different giant viruses have robust metabolic machinery, especially those in the Phycodnaviridae and Mimiviridae families. In this review, we present some peculiarities of giant viruses that infect protists and discuss why they should be seen as an outstanding source of new enzymes. We revisited the genomes of representatives of different groups of giant viruses and put together information about their enzymatic machinery, highlighting several genes to be explored in biotechnology involved in carbohydrate metabolism, DNA replication, and RNA processing, among others. Finally, we present additional evidence based on structural biology using chitinase as a model to reinforce the role of giant viruses as a source of novel enzymes for biotechnological application.
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13
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Aylward FO, Moniruzzaman M. Viral Complexity. Biomolecules 2022; 12:biom12081061. [PMID: 36008955 PMCID: PMC9405923 DOI: 10.3390/biom12081061] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Revised: 07/25/2022] [Accepted: 07/27/2022] [Indexed: 12/18/2022] Open
Abstract
Although traditionally viewed as streamlined and simple, discoveries over the last century have revealed that viruses can exhibit surprisingly complex physical structures, genomic organization, ecological interactions, and evolutionary histories. Viruses can have physical dimensions and genome lengths that exceed many cellular lineages, and their infection strategies can involve a remarkable level of physiological remodeling of their host cells. Virus–virus communication and widespread forms of hyperparasitism have been shown to be common in the virosphere, demonstrating that dynamic ecological interactions often shape their success. And the evolutionary histories of viruses are often fraught with complexities, with chimeric genomes including genes derived from numerous distinct sources or evolved de novo. Here we will discuss many aspects of this viral complexity, with particular emphasis on large DNA viruses, and provide an outlook for future research.
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Affiliation(s)
- Frank O. Aylward
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA
- Center for Emerging, Zoonotic, and Arthropod-Borne Pathogens, Virginia Tech, Blacksburg, VA 24061, USA
- Correspondence:
| | - Mohammad Moniruzzaman
- Rosenstiel School of Marine and Atmospheric Science, University of Miami, Coral Gables, FL 33149, USA;
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14
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Schulz F, Abergel C, Woyke T. Giant virus biology and diversity in the era of genome-resolved metagenomics. Nat Rev Microbiol 2022; 20:721-736. [PMID: 35902763 DOI: 10.1038/s41579-022-00754-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/25/2022] [Indexed: 11/09/2022]
Abstract
The discovery of giant viruses, with capsids as large as some bacteria, megabase-range genomes and a variety of traits typically found only in cellular organisms, was one of the most remarkable breakthroughs in biology. Until recently, most of our knowledge of giant viruses came from ~100 species-level isolates for which genome sequences were available. However, these isolates were primarily derived from laboratory-based co-cultivation with few cultured protists and algae and, thus, did not reflect the true diversity of giant viruses. Although virus co-cultures enabled valuable insights into giant virus biology, many questions regarding their origin, evolution and ecological importance remain unanswered. With advances in sequencing technologies and bioinformatics, our understanding of giant viruses has drastically expanded. In this Review, we summarize our understanding of giant virus diversity and biology based on viral isolates as laboratory cultivation has enabled extensive insights into viral morphology and infection strategies. We then explore how cultivation-independent approaches have heightened our understanding of the coding potential and diversity of the Nucleocytoviricota. We discuss how metagenomics has revolutionized our perspective of giant viruses by revealing their distribution across our planet's biomes, where they impact the biology and ecology of a wide range of eukaryotic hosts and ultimately affect global nutrient cycles.
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Affiliation(s)
- Frederik Schulz
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
| | - Chantal Abergel
- Aix Marseille University, CNRS, IGS UMR7256, IMM FR3479, IM2B, IO, Marseille, France
| | - Tanja Woyke
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA. .,University of California Merced, Merced, CA, USA.
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15
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Chase EE, Desnues C, Blanc G. Integrated Viral Elements Suggest the Dual Lifestyle of Tetraselmis Spp. Polinton-Like Viruses. Virus Evol 2022; 8:veac068. [PMID: 35949392 PMCID: PMC9356565 DOI: 10.1093/ve/veac068] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 06/30/2022] [Accepted: 07/21/2022] [Indexed: 12/03/2022] Open
Abstract
In this study, we aimed at exploring horizontal gene transfer between viruses and Chlorodendraceae green algae (Chlorophyta) using available genomic and transcriptomic sequences for twenty algal strains. We identified a significant number of genes sharing a higher sequence similarity with viral homologues, thus signalling their possible involvement in horizontal gene transfers with viruses. Further characterization showed that many of these genes were clustered in DNA regions of several tens to hundreds of kilobases in size, originally belonging to viruses related to known Tetraselmis spp. viruses (TetV and TsV). In contrast, the remaining candidate HGT genes were randomly dispersed in the algal genomes, were more frequently transcribed, and belonged to large multigene families. The presence of homologues in Viridiplantae suggested that the latter were more likely of algal rather than viral origin. We found a remarkable diversity in polinton-like virus (PLV) elements inserted in Tetraselmis genomes, all of which were most similar to the Tetraselmis striata virus (TsV). The genes of PLV elements are transcriptionally inactive with the notable exception of the homologue of the TVSG_00024 gene of TsV whose function is unknown. We suggest that this gene may be involved in a sentinel process to trigger virus reactivation and excision in response to an environmental stimulus. Altogether, these results provide evidence that TsV-related viruses have a dual lifestyle, alternating between a free viral phase (i.e. virion) and a phase integrated into host genomes.
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Affiliation(s)
- Emily E Chase
- Microbiologie Environnementale Biotechnologie, Institut Méditerranéen d’Océanologie, Campus de Luminy , 163 Avenue de Luminy, 13009 Marseille, France
- Institut hospitalo-universitaire (IHU) Méditerranée infection , 19-21 Boulevard Jean Moulin, 13005 Marseille, France
| | - Christelle Desnues
- Microbiologie Environnementale Biotechnologie, Institut Méditerranéen d’Océanologie, Campus de Luminy , 163 Avenue de Luminy, 13009 Marseille, France
- Institut hospitalo-universitaire (IHU) Méditerranée infection , 19-21 Boulevard Jean Moulin, 13005 Marseille, France
| | - Guillaume Blanc
- Microbiologie Environnementale Biotechnologie, Institut Méditerranéen d’Océanologie, Campus de Luminy , 163 Avenue de Luminy, 13009 Marseille, France
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16
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Speciale I, Notaro A, Abergel C, Lanzetta R, Lowary TL, Molinaro A, Tonetti M, Van Etten JL, De Castro C. The Astounding World of Glycans from Giant Viruses. Chem Rev 2022; 122:15717-15766. [PMID: 35820164 PMCID: PMC9614988 DOI: 10.1021/acs.chemrev.2c00118] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
![]()
Viruses are a heterogeneous ensemble of entities, all
sharing the
need for a suitable host to replicate. They are extremely diverse,
varying in morphology, size, nature, and complexity of their genomic
content. Typically, viruses use host-encoded glycosyltransferases
and glycosidases to add and remove sugar residues from their glycoproteins.
Thus, the structure of the glycans on the viral proteins have, to
date, typically been considered to mimick those of the host. However,
the more recently discovered large and giant viruses differ from this
paradigm. At least some of these viruses code for an (almost) autonomous
glycosylation pathway. These viral genes include those that encode
the production of activated sugars, glycosyltransferases, and other
enzymes able to manipulate sugars at various levels. This review focuses
on large and giant viruses that produce carbohydrate-processing enzymes.
A brief description of those harboring these features at the genomic
level will be discussed, followed by the achievements reached with
regard to the elucidation of the glycan structures, the activity of
the proteins able to manipulate sugars, and the organic synthesis
of some of these virus-encoded glycans. During this progression, we
will also comment on many of the challenging questions on this subject
that remain to be addressed.
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Affiliation(s)
- Immacolata Speciale
- Department of Agricultural Sciences, University of Napoli, Via Università 100, 80055 Portici, Italy
| | - Anna Notaro
- Department of Agricultural Sciences, University of Napoli, Via Università 100, 80055 Portici, Italy.,Centre National de la Recherche Scientifique, Information Génomique & Structurale, Aix-Marseille University, Unité Mixte de Recherche 7256, IMM, IM2B, 13288 Marseille, Cedex 9, France
| | - Chantal Abergel
- Centre National de la Recherche Scientifique, Information Génomique & Structurale, Aix-Marseille University, Unité Mixte de Recherche 7256, IMM, IM2B, 13288 Marseille, Cedex 9, France
| | - Rosa Lanzetta
- Department of Chemical Sciences, University of Napoli, Via Cintia 4, 80126 Napoli, Italy
| | - Todd L Lowary
- Institute of Biological Chemistry, Academia Sinica, Academia Road, Section 2, Nangang 11529, Taipei, Taiwan
| | - Antonio Molinaro
- Department of Chemical Sciences, University of Napoli, Via Cintia 4, 80126 Napoli, Italy
| | - Michela Tonetti
- Department of Experimental Medicine and Center of Excellence for Biomedical Research, University of Genova, 16132 Genova, Italy
| | - James L Van Etten
- Nebraska Center for Virology, University of Nebraska, Lincoln, Nebraska 68583-0900, United States.,Department of Plant Pathology, University of Nebraska, Lincoln, Nebraska 68583-0722, United States
| | - Cristina De Castro
- Department of Agricultural Sciences, University of Napoli, Via Università 100, 80055 Portici, Italy
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17
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Brahim Belhaouari D, Pires De Souza GA, Lamb DC, Kelly SL, Goldstone JV, Stegeman JJ, Colson P, La Scola B, Aherfi S. Metabolic arsenal of giant viruses: Host hijack or self-use? eLife 2022; 11:e78674. [PMID: 35801640 PMCID: PMC9270025 DOI: 10.7554/elife.78674] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 06/22/2022] [Indexed: 12/11/2022] Open
Abstract
Viruses generally are defined as lacking the fundamental properties of living organisms in that they do not harbor an energy metabolism system or protein synthesis machinery. However, the discovery of giant viruses of amoeba has fundamentally challenged this view because of their exceptional genome properties, particle sizes and encoding of the enzyme machinery for some steps of protein synthesis. Although giant viruses are not able to replicate autonomously and still require a host for their multiplication, numerous metabolic genes involved in energy production have been recently detected in giant virus genomes from many environments. These findings have further blurred the boundaries that separate viruses and living organisms. Herein, we summarize information concerning genes and proteins involved in cellular metabolic pathways and their orthologues that have, surprisingly, been discovered in giant viruses. The remarkable diversity of metabolic genes described in giant viruses include genes encoding enzymes involved in glycolysis, gluconeogenesis, tricarboxylic acid cycle, photosynthesis, and β-oxidation. These viral genes are thought to have been acquired from diverse biological sources through lateral gene transfer early in the evolution of Nucleo-Cytoplasmic Large DNA Viruses, or in some cases more recently. It was assumed that viruses are capable of hijacking host metabolic networks. But the giant virus auxiliary metabolic genes also may represent another form of host metabolism manipulation, by expanding the catalytic capabilities of the host cells especially in harsh environments, providing the infected host cells with a selective evolutionary advantage compared to non-infected cells and hence favoring the viral replication. However, the mechanism of these genes' functionality remains unclear to date.
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Affiliation(s)
- Djamal Brahim Belhaouari
- Microbes, Evolution, Phylogeny and Infection (MEPHI), UM63, Institut de Recherche pour le Développement (IRD), IHU Méditerranée Infection, Marseille, France, Aix-Marseille UniversitéMarseilleFrance
| | - Gabriel Augusto Pires De Souza
- Microbes, Evolution, Phylogeny and Infection (MEPHI), UM63, Institut de Recherche pour le Développement (IRD), IHU Méditerranée Infection, Marseille, France, Aix-Marseille UniversitéMarseilleFrance
| | - David C Lamb
- Faculty of Medicine, Health and Life Sciences, Institute of Life Science, Swansea UniversitySwanseaUnited Kingdom
| | - Steven L Kelly
- Faculty of Medicine, Health and Life Sciences, Institute of Life Science, Swansea UniversitySwanseaUnited Kingdom
| | - Jared V Goldstone
- Biology Department, Woods Hole Oceanographic InstitutionWoods HoleUnited States
| | - John J Stegeman
- Biology Department, Woods Hole Oceanographic InstitutionWoods HoleUnited States
| | - Philippe Colson
- Microbes, Evolution, Phylogeny and Infection (MEPHI), UM63, Institut de Recherche pour le Développement (IRD), IHU Méditerranée Infection, Marseille, France, Aix-Marseille UniversitéMarseilleFrance
- Assistance Publique - Hôpitaux de Marseille (AP-HM)MarseilleFrance
| | - Bernard La Scola
- Microbes, Evolution, Phylogeny and Infection (MEPHI), UM63, Institut de Recherche pour le Développement (IRD), IHU Méditerranée Infection, Marseille, France, Aix-Marseille UniversitéMarseilleFrance
- Assistance Publique - Hôpitaux de Marseille (AP-HM)MarseilleFrance
| | - Sarah Aherfi
- Microbes, Evolution, Phylogeny and Infection (MEPHI), UM63, Institut de Recherche pour le Développement (IRD), IHU Méditerranée Infection, Marseille, France, Aix-Marseille UniversitéMarseilleFrance
- Assistance Publique - Hôpitaux de Marseille (AP-HM)MarseilleFrance
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18
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Spang A, Mahendrarajah TA, Offre P, Stairs CW. Evolving perspective on the origin and diversification of cellular life and the virosphere. Genome Biol Evol 2022; 14:6537539. [PMID: 35218347 PMCID: PMC9169541 DOI: 10.1093/gbe/evac034] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/18/2022] [Indexed: 11/14/2022] Open
Abstract
The tree of life (TOL) is a powerful framework to depict the evolutionary history of cellular organisms through time, from our microbial origins to the diversification of multicellular eukaryotes that shape the visible biosphere today. During the past decades, our perception of the TOL has fundamentally changed, in part, due to profound methodological advances, which allowed a more objective approach to studying organismal and viral diversity and led to the discovery of major new branches in the TOL as well as viral lineages. Phylogenetic and comparative genomics analyses of these data have, among others, revolutionized our understanding of the deep roots and diversity of microbial life, the origin of the eukaryotic cell, eukaryotic diversity, as well as the origin, and diversification of viruses. In this review, we provide an overview of some of the recent discoveries on the evolutionary history of cellular organisms and their viruses and discuss a variety of complementary techniques that we consider crucial for making further progress in our understanding of the TOL and its interconnection with the virosphere.
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Affiliation(s)
- Anja Spang
- NIOZ, Royal Netherlands Institute for Sea Research, Department of Marine Microbiology and Biogeochemistry, Utrecht University, The Netherlands and 1790 AB Den Burg.,Department of Cell- and Molecular Biology, Science for Life Laboratory, Uppsala University, Sweden SE-75123, Uppsala
| | - Tara A Mahendrarajah
- NIOZ, Royal Netherlands Institute for Sea Research, Department of Marine Microbiology and Biogeochemistry, Utrecht University, The Netherlands and 1790 AB Den Burg
| | - Pierre Offre
- NIOZ, Royal Netherlands Institute for Sea Research, Department of Marine Microbiology and Biogeochemistry, Utrecht University, The Netherlands and 1790 AB Den Burg
| | - Courtney W Stairs
- Department of Biology, Lund University, Sweden Sölvegatan 35, 223 62 Lund
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19
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Irwin NAT, Pittis AA, Richards TA, Keeling PJ. Systematic evaluation of horizontal gene transfer between eukaryotes and viruses. Nat Microbiol 2021; 7:327-336. [PMID: 34972821 DOI: 10.1038/s41564-021-01026-3] [Citation(s) in RCA: 71] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Accepted: 11/12/2021] [Indexed: 01/19/2023]
Abstract
Gene exchange between viruses and their hosts acts as a key facilitator of horizontal gene transfer and is hypothesized to be a major driver of evolutionary change. Our understanding of this process comes primarily from bacteria and phage co-evolution, but the mode and functional importance of gene transfers between eukaryotes and their viruses remain anecdotal. Here we systematically characterized viral-eukaryotic gene exchange across eukaryotic and viral diversity, identifying thousands of transfers and revealing their frequency, taxonomic distribution and projected functions. Eukaryote-derived viral genes, abundant in the Nucleocytoviricota, highlighted common strategies for viral host-manipulation, including metabolic reprogramming, proteolytic degradation and extracellular modification. Furthermore, viral-derived eukaryotic genes implicate genetic exchange in the early evolution and diversification of eukaryotes, particularly through viral-derived glycosyltransferases, which have impacted structures as diverse as algal cell walls, trypanosome mitochondria and animal tissues. These findings illuminate the nature of viral-eukaryotic gene exchange and its impact on the evolution of viruses and their eukaryotic hosts.
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Affiliation(s)
- Nicholas A T Irwin
- Merton College, University of Oxford, Oxford, UK. .,Department of Zoology, University of Oxford, Oxford, UK. .,Department of Botany, University of British Columbia, Vancouver, British Columbia, Canada.
| | - Alexandros A Pittis
- Department of Botany, University of British Columbia, Vancouver, British Columbia, Canada
| | | | - Patrick J Keeling
- Department of Botany, University of British Columbia, Vancouver, British Columbia, Canada
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20
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Aylward FO, Moniruzzaman M, Ha AD, Koonin EV. A phylogenomic framework for charting the diversity and evolution of giant viruses. PLoS Biol 2021; 19:e3001430. [PMID: 34705818 PMCID: PMC8575486 DOI: 10.1371/journal.pbio.3001430] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 11/08/2021] [Accepted: 09/29/2021] [Indexed: 11/22/2022] Open
Abstract
Large DNA viruses of the phylum Nucleocytoviricota have recently emerged as important members of ecosystems around the globe that challenge traditional views of viral complexity. Numerous members of this phylum that cannot be classified within established families have recently been reported, and there is presently a strong need for a robust phylogenomic and taxonomic framework for these viruses. Here, we report a comprehensive phylogenomic analysis of the Nucleocytoviricota, present a set of giant virus orthologous groups (GVOGs) together with a benchmarked reference phylogeny, and delineate a hierarchical taxonomy within this phylum. We show that the majority of Nucleocytoviricota diversity can be partitioned into 6 orders, 32 families, and 344 genera, substantially expanding the number of currently recognized taxonomic ranks for these viruses. We integrate our results within a taxonomy that has been adopted for all viruses to establish a unifying framework for the study of Nucleocytoviricota diversity, evolution, and environmental distribution. Giant viruses have transformed our understanding of viral complexity, but we lack a framework for examining their diversity in the biosphere. This study presents a phylogenomic resource for charting the diversity, ecology, and evolution of giant viruses.
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Affiliation(s)
- Frank O. Aylward
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, United States of America
- Center for Emerging, Zoonotic, and Arthropod-borne Pathogens, Virginia Tech, Blacksburg, Virginia, United States of America
- * E-mail:
| | - Mohammad Moniruzzaman
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, United States of America
| | - Anh D. Ha
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, United States of America
| | - Eugene V. Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, United States of America
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21
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Incomplete tricarboxylic acid cycle and proton gradient in Pandoravirus massiliensis: is it still a virus? ISME JOURNAL 2021; 16:695-704. [PMID: 34556816 PMCID: PMC8857278 DOI: 10.1038/s41396-021-01117-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 08/24/2021] [Accepted: 09/10/2021] [Indexed: 11/24/2022]
Abstract
The discovery of Acanthamoeba polyphaga Mimivirus, the first isolated giant virus of amoeba, challenged the historical hallmarks defining a virus. Giant virion sizes are known to reach up to 2.3 µm, making them visible by optical microscopy. Their large genome sizes of up to 2.5 Mb can encode proteins involved in the translation apparatus. We have investigated possible energy production in Pandoravirus massiliensis. Mitochondrial membrane markers allowed for the detection of a membrane potential in purified virions and this was enhanced by a regulator of the tricarboxylic acid cycle but abolished by the use of a depolarizing agent. Bioinformatics was employed to identify enzymes involved in virion proton gradient generation and this approach revealed that eight putative P. massiliensis proteins exhibited low sequence identities with known cellular enzymes involved in the universal tricarboxylic acid cycle. Further, all eight viral genes were transcribed during replication. The product of one of these genes, ORF132, was cloned and expressed in Escherichia coli, and shown to function as an isocitrate dehydrogenase, a key enzyme of the tricarboxylic acid cycle. Our findings show for the first time that a membrane potential can exist in Pandoraviruses, and this may be related to tricarboxylic acid cycle. The presence of a proton gradient in P. massiliensis makes this virus a form of life for which it is legitimate to ask the question “what is a virus?”.
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22
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Ha AD, Moniruzzaman M, Aylward FO. High Transcriptional Activity and Diverse Functional Repertoires of Hundreds of Giant Viruses in a Coastal Marine System. mSystems 2021; 6:e0029321. [PMID: 34254826 PMCID: PMC8407384 DOI: 10.1128/msystems.00293-21] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 05/26/2021] [Indexed: 12/14/2022] Open
Abstract
Viruses belonging to the Nucleocytoviricota phylum are globally distributed and include members with notably large genomes and complex functional repertoires. Recent studies have shown that these viruses are particularly diverse and abundant in marine systems, but the magnitude of actively replicating Nucleocytoviricota present in ocean habitats remains unclear. In this study, we compiled a curated database of 2,431 Nucleocytoviricota genomes and used it to examine the gene expression of these viruses in a 2.5-day metatranscriptomic time-series from surface waters of the California Current. We identified 145 viral genomes with high levels of gene expression, including 90 Imitervirales and 49 Algavirales viruses. In addition to recovering high expression of core genes involved in information processing that are commonly expressed during viral infection, we also identified transcripts of diverse viral metabolic genes from pathways such as glycolysis, the TCA cycle, and the pentose phosphate pathway, suggesting that virus-mediated reprogramming of central carbon metabolism is common in oceanic surface waters. Surprisingly, we also identified viral transcripts with homology to actin, myosin, and kinesin domains, suggesting that viruses may use these gene products to manipulate host cytoskeletal dynamics during infection. We performed phylogenetic analysis on the virus-encoded myosin and kinesin proteins, which demonstrated that most belong to deep-branching viral clades, but that others appear to have been acquired from eukaryotes more recently. Our results highlight a remarkable diversity of active Nucleocytoviricota in a coastal marine system and underscore the complex functional repertoires expressed by these viruses during infection. IMPORTANCE The discovery of giant viruses has transformed our understanding of viral complexity. Although viruses have traditionally been viewed as filterable infectious agents that lack metabolism, giant viruses can reach sizes rivalling cellular lineages and possess genomes encoding central metabolic processes. Recent studies have shown that giant viruses are widespread in aquatic systems, but the activity of these viruses and the extent to which they reprogram host physiology in situ remains unclear. Here, we show that numerous giant viruses consistently express central metabolic enzymes in a coastal marine system, including components of glycolysis, the TCA cycle, and other pathways involved in nutrient homeostasis. Moreover, we found expression of several viral-encoded actin, myosin, and kinesin genes, indicating viral manipulation of the host cytoskeleton during infection. Our study reveals a high activity of giant viruses in a coastal marine system and indicates they are a diverse and underappreciated component of microbial diversity in the ocean.
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Affiliation(s)
- Anh D. Ha
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | | | - Frank O. Aylward
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA
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23
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Nelson DR, Hazzouri KM, Lauersen KJ, Jaiswal A, Chaiboonchoe A, Mystikou A, Fu W, Daakour S, Dohai B, Alzahmi A, Nobles D, Hurd M, Sexton J, Preston MJ, Blanchette J, Lomas MW, Amiri KMA, Salehi-Ashtiani K. Large-scale genome sequencing reveals the driving forces of viruses in microalgal evolution. Cell Host Microbe 2021; 29:250-266.e8. [PMID: 33434515 DOI: 10.1016/j.chom.2020.12.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 10/08/2020] [Accepted: 11/18/2020] [Indexed: 01/08/2023]
Abstract
Being integral primary producers in diverse ecosystems, microalgal genomes could be mined for ecological insights, but representative genome sequences are lacking for many phyla. We cultured and sequenced 107 microalgae species from 11 different phyla indigenous to varied geographies and climates. This collection was used to resolve genomic differences between saltwater and freshwater microalgae. Freshwater species showed domain-centric ontology enrichment for nuclear and nuclear membrane functions, while saltwater species were enriched in organellar and cellular membrane functions. Further, marine species contained significantly more viral families in their genomes (p = 8e-4). Sequences from Chlorovirus, Coccolithovirus, Pandoravirus, Marseillevirus, Tupanvirus, and other viruses were found integrated into the genomes of algal from marine environments. These viral-origin sequences were found to be expressed and code for a wide variety of functions. Together, this study comprehensively defines the expanse of protein-coding and viral elements in microalgal genomes and posits a unified adaptive strategy for algal halotolerance.
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Affiliation(s)
- David R Nelson
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE.
| | - Khaled M Hazzouri
- Khalifa Center for Genetic Engineering and Biotechnology (KCGEB), UAE University, Al Ain, Abu Dhabi, UAE; Biology Department, College of Science, UAE University, Al Ain, Abu Dhabi, UAE
| | - Kyle J Lauersen
- Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Kingdom of Saudi Arabia
| | - Ashish Jaiswal
- Division of Science and Math, New York University Abu Dhabi, Abu Dhabi, UAE
| | | | - Alexandra Mystikou
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE
| | - Weiqi Fu
- Division of Science and Math, New York University Abu Dhabi, Abu Dhabi, UAE
| | - Sarah Daakour
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE
| | - Bushra Dohai
- Division of Science and Math, New York University Abu Dhabi, Abu Dhabi, UAE
| | - Amnah Alzahmi
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE
| | - David Nobles
- UTEX Culture Collection of Algae at the University of Texas at Austin, Austin, TX, USA
| | - Mark Hurd
- National Center for Marine Algae and Microbiota, East Boothbay, ME, USA
| | - Julie Sexton
- National Center for Marine Algae and Microbiota, East Boothbay, ME, USA
| | - Michael J Preston
- National Center for Marine Algae and Microbiota, East Boothbay, ME, USA
| | - Joan Blanchette
- National Center for Marine Algae and Microbiota, East Boothbay, ME, USA
| | - Michael W Lomas
- National Center for Marine Algae and Microbiota, East Boothbay, ME, USA
| | - Khaled M A Amiri
- Khalifa Center for Genetic Engineering and Biotechnology (KCGEB), UAE University, Al Ain, Abu Dhabi, UAE; Biology Department, College of Science, UAE University, Al Ain, Abu Dhabi, UAE
| | - Kourosh Salehi-Ashtiani
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE; Division of Science and Math, New York University Abu Dhabi, Abu Dhabi, UAE.
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24
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Hunter P. A bag of genes and surprises: Giant viruses continue to fascinate researchers for their role in eukaryote evolution and ecology. EMBO Rep 2021; 22:e53464. [PMID: 34288334 DOI: 10.15252/embr.202153464] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 06/21/2021] [Indexed: 11/09/2022] Open
Abstract
Giant viruses continue to yield fascinating discoveries from ancient eukaryotic immune defenses to viruses' role in the global carbon cycle.
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25
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The Secret Life of Giant Viruses in the California Current. mSystems 2021; 6:e0075121. [PMID: 34254818 PMCID: PMC8407427 DOI: 10.1128/msystems.00751-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In the last few decades, the virology field has experienced a revolution in knowledge related to viral richness, diversity, and distribution in the oceans. Metagenomics associated with virus isolation methods have contributed to outstanding discoveries in marine virology. Giant viruses and other protist-infecting viruses belonging to the phylum Nucleocytoviricota have raised fundamental questions such as “what are the limits of virion size?”, “what is a viral genome able to encode?”, and “what is the ecological role of giant viruses in the ocean?” In a recent paper published in mSystems by Ha, Moniruzzaman, and Aylward (mSystems 6:e00293-21, 2021, https://doi.org/10.1128/mSystems.00293-21), the authors demonstrated by metatranscriptomic-related analyses that giant viruses are active members of the California Current microbial community, replicating, modulating, and exchanging genes with their protist hosts. This work not only explores the dynamics of giant virus gene expression in a natural environment but also reveals that nucleocytoviricotal abundance and ecological importance are underestimated.
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26
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Prospects for viruses infecting eukaryotic microalgae in biotechnology. Biotechnol Adv 2021; 54:107790. [PMID: 34182051 DOI: 10.1016/j.biotechadv.2021.107790] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 06/02/2021] [Accepted: 06/18/2021] [Indexed: 12/16/2022]
Abstract
Besides being considered pathogens, viruses are important drivers of evolution and they can shape large ecological and biogeochemical processes, by influencing host fitness, population dynamics, and community structures. Moreover, they are simple systems that can be used and manipulated to be beneficial and useful for biotechnological applications. In this context, microalgae biotechnology is a growing field of research, which investigated the usage of photosynthetic microorganisms for the sustainable production of food, fuel, chemical, and pharmaceutical sectors. Viruses infecting microalgae have become important subject of ecological studies related to marine and aquatic environments only four decades ago when virus-like-particles associated with bloom-forming algae were discovered. These first findings have opened new questions on evolution and identity. To date, 63 viruses that infect eukaryotic microalgae have been isolated and cultured. In this short review we briefly summarize what is known about viruses infecting eukaryotic microalgae, and how acknowledging their importance can shape future research focussed not only on marine ecology and evolutionary biology but also on biotechnological applications related to microalgae cell factories.
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27
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Ibrahim A, Colson P, Merhej V, Zgheib R, Maatouk M, Naud S, Bittar F, Raoult D. Rhizomal Reclassification of Living Organisms. Int J Mol Sci 2021; 22:5643. [PMID: 34073251 PMCID: PMC8199106 DOI: 10.3390/ijms22115643] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 05/14/2021] [Accepted: 05/23/2021] [Indexed: 12/11/2022] Open
Abstract
Living organisms interact with each other during their lifetime, leading to genomes rearrangement and sequences transfer. These well-known phenomena give these organisms mosaic genomes, which challenge their classification. Moreover, many findings occurred between the IXXth and XXIst century, especially the discovery of giant viruses and candidate phyla radiation (CPR). Here, we tried to provide an updated classification, which integrates 216 representative genomes of the current described organisms. The reclassification was expressed through a genetic network based on the total genomic content, not on a single gene to represent the tree of life. This rhizomal exploration represents, more accurately, the evolutionary relationships among the studied species. Our analyses show a separated branch named fifth TRUC (Things Resisting Uncompleted Classifications). This taxon groups CPRs together, independently from Bacteria, Archaea (which regrouped also Nanoarchaeota and Asgard members), Eukarya, and the giant viruses (recognized recently as fourth TRUC). Finally, the broadening of analysis methods will lead to the discovery of new organisms, which justify the importance of updating the classification at every opportunity. In this perspective, our pragmatic representation could be adjusted along with the progress of evolutionary studies.
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Affiliation(s)
- Ahmad Ibrahim
- IHU Méditerranée Infection, 13005 Marseille, France; (A.I.); (P.C.); (V.M.); (R.Z.); (M.M.); (S.N.)
- Aix-Marseille Université, IRD, APHM, MEPHI, 13005 Marseille, France
| | - Philippe Colson
- IHU Méditerranée Infection, 13005 Marseille, France; (A.I.); (P.C.); (V.M.); (R.Z.); (M.M.); (S.N.)
- Aix-Marseille Université, IRD, APHM, MEPHI, 13005 Marseille, France
| | - Vicky Merhej
- IHU Méditerranée Infection, 13005 Marseille, France; (A.I.); (P.C.); (V.M.); (R.Z.); (M.M.); (S.N.)
- Aix-Marseille Université, IRD, APHM, MEPHI, 13005 Marseille, France
| | - Rita Zgheib
- IHU Méditerranée Infection, 13005 Marseille, France; (A.I.); (P.C.); (V.M.); (R.Z.); (M.M.); (S.N.)
- Aix-Marseille Université, IRD, APHM, SSA, VITROME, 13005 Marseille, France
| | - Mohamad Maatouk
- IHU Méditerranée Infection, 13005 Marseille, France; (A.I.); (P.C.); (V.M.); (R.Z.); (M.M.); (S.N.)
- Aix-Marseille Université, IRD, APHM, MEPHI, 13005 Marseille, France
| | - Sabrina Naud
- IHU Méditerranée Infection, 13005 Marseille, France; (A.I.); (P.C.); (V.M.); (R.Z.); (M.M.); (S.N.)
- Aix-Marseille Université, IRD, APHM, MEPHI, 13005 Marseille, France
| | - Fadi Bittar
- IHU Méditerranée Infection, 13005 Marseille, France; (A.I.); (P.C.); (V.M.); (R.Z.); (M.M.); (S.N.)
- Aix-Marseille Université, IRD, APHM, MEPHI, 13005 Marseille, France
| | - Didier Raoult
- IHU Méditerranée Infection, 13005 Marseille, France; (A.I.); (P.C.); (V.M.); (R.Z.); (M.M.); (S.N.)
- Aix-Marseille Université, IRD, APHM, MEPHI, 13005 Marseille, France
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28
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Gallot-Lavallée L, Archibald JM. Evolutionary Biology: Viral Rhodopsins Illuminate Algal Evolution. Curr Biol 2021; 30:R1469-R1471. [PMID: 33352125 DOI: 10.1016/j.cub.2020.10.080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A new metagenomics study has shown that marine viruses recently acquired genes encoding light-gated ion channels from green algae. These so-called channelrhodopsin genes may allow the viruses to manipulate the swimming behavior of the algae they infect.
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Affiliation(s)
- Lucie Gallot-Lavallée
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS, Canada
| | - John M Archibald
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS, Canada.
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A persistent giant algal virus, with a unique morphology, encodes an unprecedented number of genes involved in energy metabolism. J Virol 2021; 95:JVI.02446-20. [PMID: 33536167 PMCID: PMC8103676 DOI: 10.1128/jvi.02446-20] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Viruses have long been viewed as entities possessing extremely limited metabolic capacities. Over the last decade, however, this view has been challenged, as metabolic genes have been identified in viruses possessing large genomes and virions-the synthesis of which is energetically demanding. Here, we unveil peculiar phenotypic and genomic features of Prymnesium kappa virus RF01 (PkV RF01), a giant virus of the Mimiviridae family. We found that this virus encodes an unprecedented number of proteins involved in energy metabolism, such as all four succinate dehydrogenase (SDH) subunits (A-D) as well as key enzymes in the β-oxidation pathway. The SDHA gene was transcribed upon infection, indicating that the viral SDH is actively used by the virus- potentially to modulate its host's energy metabolism. We detected orthologous SDHA and SDHB genes in numerous genome fragments from uncultivated marine Mimiviridae viruses, which suggests that the viral SDH is widespread in oceans. PkV RF01 was less virulent compared with other cultured prymnesioviruses, a phenomenon possibly linked to the metabolic capacity of this virus and suggestive of relatively long co-evolution with its hosts. It also has a unique morphology, compared to other characterized viruses in the Mimiviridae family. Finally, we found that PkV RF01 is the only alga-infecting Mimiviridae virus encoding two aminoacyl-tRNA synthetases and enzymes corresponding to an entire base-excision repair pathway, as seen in heterotroph-infecting Mimiviridae These Mimiviridae encoded-enzymes were found to be monophyletic and branching at the root of the eukaryotic tree of life. This placement suggests that the last common ancestor of Mimiviridae was endowed with a large, complex genome prior to the divergence of known extant eukaryotes.IMPORTANCE Viruses on Earth are tremendously diverse in terms of morphology, functionality, and genomic composition. Over the last decade, the conceptual gap separating viruses and cellular life has tightened because of the detection of metabolic genes in viral genomes that express complex virus phenotypes upon infection. Here, we describe Prymnesium kappa virus RF01, a large alga-infecting virus with a unique morphology, an atypical infection profile, and an unprecedented number of genes involved in energy metabolism (such as the tricarboxylic (TCA) cycle and the β-oxidation pathway). Moreover, we show that the gene corresponding to one of these enzymes (the succinate dehydrogenase subunit A) is transcribed during infection and is widespread among marine viruses. This discovery provides evidence that a virus has the potential to actively regulate energy metabolism with its own gene.
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Karki S, Moniruzzaman M, Aylward FO. Comparative Genomics and Environmental Distribution of Large dsDNA Viruses in the Family Asfarviridae. Front Microbiol 2021; 12:657471. [PMID: 33790885 PMCID: PMC8005611 DOI: 10.3389/fmicb.2021.657471] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Accepted: 02/22/2021] [Indexed: 12/14/2022] Open
Abstract
The family Asfarviridae is a group of nucleo-cytoplasmic large DNA viruses (NCLDVs) of which African swine fever virus (ASFV) is well-characterized. Recently the discovery of several Asfarviridae members other than ASFV has suggested that this family represents a diverse and cosmopolitan group of viruses, but the genomics and distribution of this family have not been studied in detail. To this end we analyzed five complete genomes and 35 metagenome-assembled genomes (MAGs) of viruses from this family to shed light on their evolutionary relationships and environmental distribution. The Asfarvirus MAGs derive from diverse marine, freshwater, and terrestrial habitats, underscoring the broad environmental distribution of this family. We present phylogenetic analyses using conserved marker genes and whole-genome comparison of pairwise average amino acid identity (AAI) values, revealing a high level of genomic divergence across disparate Asfarviruses. Further, we found that Asfarviridae genomes encode genes with diverse predicted metabolic roles and detectable sequence homology to proteins in bacteria, archaea, and eukaryotes, highlighting the genomic chimerism that is a salient feature of NCLDV. Our read mapping from Tara oceans metagenomic data also revealed that three Asfarviridae MAGs were present in multiple marine samples, indicating that they are widespread in the ocean. In one of these MAGs we identified four marker genes with > 95% AAI to genes sequenced from a virus that infects the dinoflagellate Heterocapsa circularisquama (HcDNAV). This suggests a potential host for this MAG, which would thereby represent a reference genome of a dinoflagellate-infecting giant virus. Together, these results show that Asfarviridae are ubiquitous, comprise similar sequence divergence as other NCLDV families, and include several members that are widespread in the ocean and potentially infect ecologically important protists.
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Affiliation(s)
- Sangita Karki
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, United States
| | | | - Frank O Aylward
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, United States
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31
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Aylward FO, Moniruzzaman M. ViralRecall-A Flexible Command-Line Tool for the Detection of Giant Virus Signatures in 'Omic Data. Viruses 2021; 13:v13020150. [PMID: 33498458 PMCID: PMC7909515 DOI: 10.3390/v13020150] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 01/07/2021] [Accepted: 01/18/2021] [Indexed: 01/06/2023] Open
Abstract
Giant viruses are widespread in the biosphere and play important roles in biogeochemical cycling and host genome evolution. Also known as nucleo-cytoplasmic large DNA viruses (NCLDVs), these eukaryotic viruses harbor the largest and most complex viral genomes known. Studies have shown that NCLDVs are frequently abundant in metagenomic datasets, and that sequences derived from these viruses can also be found endogenized in diverse eukaryotic genomes. The accurate detection of sequences derived from NCLDVs is therefore of great importance, but this task is challenging owing to both the high level of sequence divergence between NCLDV families and the extraordinarily high diversity of genes encoded in their genomes, including some encoding for metabolic or translation-related functions that are typically found only in cellular lineages. Here, we present ViralRecall, a bioinformatic tool for the identification of NCLDV signatures in ‘omic data. This tool leverages a library of giant virus orthologous groups (GVOGs) to identify sequences that bear signatures of NCLDVs. We demonstrate that this tool can effectively identify NCLDV sequences with high sensitivity and specificity. Moreover, we show that it can be useful both for removing contaminating sequences in metagenome-assembled viral genomes as well as the identification of eukaryotic genomic loci that derived from NCLDV. ViralRecall is written in Python 3.5 and is freely available on GitHub: https://github.com/faylward/viralrecall.
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32
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Sorouri M, Chang T, Jesudhasan P, Pinkham C, Elde NC, Hancks DC. Signatures of host-pathogen evolutionary conflict reveal MISTR-A conserved MItochondrial STress Response network. PLoS Biol 2020; 18:e3001045. [PMID: 33370271 PMCID: PMC7793259 DOI: 10.1371/journal.pbio.3001045] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 01/08/2021] [Accepted: 12/09/2020] [Indexed: 11/18/2022] Open
Abstract
Host-pathogen conflicts leave genetic signatures in genes that are critical for host defense functions. Using these "molecular scars" as a guide to discover gene functions, we discovered a vertebrate-specific MItochondrial STress Response (MISTR) circuit. MISTR proteins are associated with electron transport chain (ETC) factors and activated by stress signals such as interferon gamma (IFNγ) and hypoxia. Upon stress, ultraconserved microRNAs (miRNAs) down-regulate MISTR1(NDUFA4) followed by replacement with paralogs MItochondrial STress Response AntiViral (MISTRAV) and/or MItochondrial STress Response Hypoxia (MISTRH). While cells lacking MISTR1(NDUFA4) are more sensitive to chemical and viral apoptotic triggers, cells lacking MISTRAV or expressing the squirrelpox virus-encoded vMISTRAV exhibit resistance to the same insults. Rapid evolution signatures across primate genomes for MISTR1(NDUFA4) and MISTRAV indicate recent and ongoing conflicts with pathogens. MISTR homologs are also found in plants, yeasts, a fish virus, and an algal virus indicating ancient origins and suggesting diverse means of altering mitochondrial function under stress. The discovery of MISTR circuitry highlights the use of evolution-guided studies to reveal fundamental biological processes.
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Affiliation(s)
- Mahsa Sorouri
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Institute of Biomedical Studies, Baylor University, Waco, Texas, United States of America
| | - Tyron Chang
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Genetics, Development, and Disease PhD Program, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Palmy Jesudhasan
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Chelsea Pinkham
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Nels C. Elde
- Eccles Institute of Human Genetics, The University of Utah Medical School, Utah, United States of America
- * E-mail: (NCE); (DCH)
| | - Dustin C. Hancks
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- * E-mail: (NCE); (DCH)
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33
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Sun Z, Fu J, Li X, Blatchley ER, Zhou Z. Using Algal Virus Paramecium bursaria Chlorella Virus as a Human Adenovirus Surrogate for Validation of UV Treatment Systems. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:15507-15515. [PMID: 33166135 DOI: 10.1021/acs.est.0c06354] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Adenovirus is among the most UV-resistant waterborne human pathogens. There is a need to identify nonpathogenic surrogates for adenovirus for the water treatment industry. In this study, the feasibility of using the algal virus Paramecium bursaria chlorella virus (PBCV-1) as an adenovirus surrogate for validation of UV reactors was evaluated. The UV dose-response behavior of PBCV-1 to monochromatic UV radiation at 254 nm and action spectrum for wavelengths ranging from 214 to 289 nm were measured. A culture-based infectivity assay was used to evaluate viral inactivation, and a quantitative PCR assay was used to quantify DNA damage. A UV254 dose of 150 mJ/cm2 resulted in roughly 5-log10 units of reduction of PBCV-1, which is similar to that of adenovirus. Furthermore, the inactivation action spectrum of PBCV-1 was similar to that of adenovirus between 214 and 289 nm. A simplified and inexpensive prepurification method was also developed to prepare PBCV-1 viral suspensions with similar inactivation behavior to purified PBCV-1. Overall, PBCV-1 appears to represent an appropriate adenovirus surrogate for UV system performance evaluation and illustrates the potential of using algal viruses as nonpathogenic, easy to culture, and readily available surrogates for human pathogens.
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Affiliation(s)
- Zhe Sun
- Lyles School of Civil Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Jianing Fu
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907, United States
| | - Xing Li
- Lyles School of Civil Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Ernest R Blatchley
- Lyles School of Civil Engineering, Purdue University, West Lafayette, Indiana 47907, United States
- Division of Environmental and Ecological Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Zhi Zhou
- Lyles School of Civil Engineering, Purdue University, West Lafayette, Indiana 47907, United States
- Division of Environmental and Ecological Engineering, Purdue University, West Lafayette, Indiana 47907, United States
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34
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Sun TW, Yang CL, Kao TT, Wang TH, Lai MW, Ku C. Host Range and Coding Potential of Eukaryotic Giant Viruses. Viruses 2020; 12:E1337. [PMID: 33233432 PMCID: PMC7700475 DOI: 10.3390/v12111337] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 11/19/2020] [Accepted: 11/19/2020] [Indexed: 12/11/2022] Open
Abstract
Giant viruses are a group of eukaryotic double-stranded DNA viruses with large virion and genome size that challenged the traditional view of virus. Newly isolated strains and sequenced genomes in the last two decades have substantially advanced our knowledge of their host diversity, gene functions, and evolutionary history. Giant viruses are now known to infect hosts from all major supergroups in the eukaryotic tree of life, which predominantly comprises microbial organisms. The seven well-recognized viral clades (taxonomic families) have drastically different host range. Mimiviridae and Phycodnaviridae, both with notable intrafamilial genome variation and high abundance in environmental samples, have members that infect the most diverse eukaryotic lineages. Laboratory experiments and comparative genomics have shed light on the unprecedented functional potential of giant viruses, encoding proteins for genetic information flow, energy metabolism, synthesis of biomolecules, membrane transport, and sensing that allow for sophisticated control of intracellular conditions and cell-environment interactions. Evolutionary genomics can illuminate how current and past hosts shape viral gene repertoires, although it becomes more obscure with divergent sequences and deep phylogenies. Continued works to characterize giant viruses from marine and other environments will further contribute to our understanding of their host range, coding potential, and virus-host coevolution.
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Affiliation(s)
- Tsu-Wang Sun
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan; (T.-W.S.); (C.-L.Y.); (T.-T.K.); (T.-H.W.); (M.-W.L.)
- Genome and Systems Biology Degree Program, National Taiwan University and Academia Sinica, Taipei 10617, Taiwan
| | - Chia-Ling Yang
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan; (T.-W.S.); (C.-L.Y.); (T.-T.K.); (T.-H.W.); (M.-W.L.)
| | - Tzu-Tong Kao
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan; (T.-W.S.); (C.-L.Y.); (T.-T.K.); (T.-H.W.); (M.-W.L.)
| | - Tzu-Haw Wang
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan; (T.-W.S.); (C.-L.Y.); (T.-T.K.); (T.-H.W.); (M.-W.L.)
| | - Ming-Wei Lai
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan; (T.-W.S.); (C.-L.Y.); (T.-T.K.); (T.-H.W.); (M.-W.L.)
| | - Chuan Ku
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan; (T.-W.S.); (C.-L.Y.); (T.-T.K.); (T.-H.W.); (M.-W.L.)
- Genome and Systems Biology Degree Program, National Taiwan University and Academia Sinica, Taipei 10617, Taiwan
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35
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Moniruzzaman M, Weinheimer AR, Martinez-Gutierrez CA, Aylward FO. Widespread endogenization of giant viruses shapes genomes of green algae. Nature 2020; 588:141-145. [PMID: 33208937 DOI: 10.1038/s41586-020-2924-2] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 09/01/2020] [Indexed: 12/21/2022]
Abstract
Endogenous viral elements (EVEs)-viruses that have integrated their genomes into those of their hosts-are prevalent in eukaryotes and have an important role in genome evolution1,2. The vast majority of EVEs that have been identified to date are small genomic regions comprising a few genes2, but recent evidence suggests that some large double-stranded DNA viruses may also endogenize into the genome of the host1. Nucleocytoplasmic large DNA viruses (NCLDVs) have recently become of great interest owing to their large genomes and complex evolutionary origins3-6, but it is not yet known whether they are a prominent component of eukaryotic EVEs. Here we report the widespread endogenization of NCLDVs in diverse green algae; these giant EVEs reached sizes greater than 1 million base pairs and contained as many as around 10% of the total open reading frames in some genomes, substantially increasing the scale of known viral genes in eukaryotic genomes. These endogenized elements often shared genes with host genomic loci and contained numerous spliceosomal introns and large duplications, suggesting tight assimilation into host genomes. NCLDVs contain large and mosaic genomes with genes derived from multiple sources, and their endogenization represents an underappreciated conduit of new genetic material into eukaryotic lineages that can substantially impact genome composition.
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Affiliation(s)
| | | | | | - Frank O Aylward
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, USA.
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36
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Lateral Gene Transfer Mechanisms and Pan-genomes in Eukaryotes. Trends Parasitol 2020; 36:927-941. [DOI: 10.1016/j.pt.2020.07.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 07/20/2020] [Accepted: 07/20/2020] [Indexed: 02/06/2023]
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37
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Shrinking of repeating unit length in leucine-rich repeats from double-stranded DNA viruses. Arch Virol 2020; 166:43-64. [PMID: 33052487 DOI: 10.1007/s00705-020-04820-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 08/19/2020] [Indexed: 02/07/2023]
Abstract
Leucine-rich repeats (LRRs) are present in over 563,000 proteins from viruses to eukaryotes. LRRs repeat in tandem and have been classified into fifteen classes in which the repeat unit lengths range from 20 to 29 residues. Most LRR proteins are involved in protein-protein or ligand interactions. The amount of genome sequence data from viruses is increasing rapidly, and although viral LRR proteins have been identified, a comprehensive sequence analysis has not yet been done, and their structures, functions, and evolution are still unknown. In the present study, we characterized viral LRRs by sequence analysis and identified over 600 LRR proteins from 89 virus species. Most of these proteins were from double-stranded DNA (dsDNA) viruses, including nucleocytoplasmic large dsDNA viruses (NCLDVs). We found that the repeating unit lengths of 11 types are one to five residues shorter than those of the seven known corresponding LRR classes. The repeating units of six types are 19 residues long and are thus the shortest among all LRRs. In addition, two of the LRR types are unique and have not been observed in bacteria, archae or eukaryotes. Conserved strongly hydrophobic residues such as Leu, Val or Ile in the consensus sequences are replaced by Cys with high frequency. Phylogenetic analysis indicated that horizontal gene transfer of some viral LRR genes had occurred between the virus and its host. We suggest that the shortening might contribute to the survival strategy of viruses. The present findings provide a new perspective on the origin and evolution of LRRs.
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Chelkha N, Levasseur A, La Scola B, Colson P. Host-virus interactions and defense mechanisms for giant viruses. Ann N Y Acad Sci 2020; 1486:39-57. [PMID: 33090482 DOI: 10.1111/nyas.14469] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Revised: 06/28/2020] [Accepted: 07/26/2020] [Indexed: 12/26/2022]
Abstract
Giant viruses, with virions larger than 200 nm and genomes larger than 340 kilobase pairs, modified the now outdated perception of the virosphere. With virions now reported reaching up to 1.5 μm in size and genomes of up to 2.5 Mb encoding components shared with cellular life forms, giant viruses exhibit a complexity similar to microbes, such as bacteria and archaea. Here, we review interactions of giant viruses with their hosts and defense strategies of giant viruses against their hosts and coinfecting microorganisms or virophages. We also searched by comparative genomics for homologies with proteins described or suspected to be involved in defense mechanisms. Our search reveals that natural immunity and apoptosis seem to be crucial components of the host defense against giant virus infection. Conversely, giant viruses possess methods of hijacking host functions to counteract cellular antiviral responses. In addition, giant viruses may encode other unique and complex pathways to manipulate the host machinery and eliminate other competing microorganisms. Notably, giant viruses have evolved defense mechanisms against their virophages and they might trigger defense systems against other viruses through sequence integration. We anticipate that comparative genomics may help identifying genes involved in defense strategies of both giant viruses and their hosts.
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Affiliation(s)
- Nisrine Chelkha
- Aix-Marseille University, Institut de Recherche pour le Développement (IRD), Assistance Publique - Hôpitaux de Marseille (AP-HM), Microbes Evolution Phylogeny and Infections (MEPHI), Marseille, France
| | - Anthony Levasseur
- Aix-Marseille University, Institut de Recherche pour le Développement (IRD), Assistance Publique - Hôpitaux de Marseille (AP-HM), Microbes Evolution Phylogeny and Infections (MEPHI), Marseille, France
- IHU Méditerranée Infection, Marseille, France
| | - Bernard La Scola
- Aix-Marseille University, Institut de Recherche pour le Développement (IRD), Assistance Publique - Hôpitaux de Marseille (AP-HM), Microbes Evolution Phylogeny and Infections (MEPHI), Marseille, France
- IHU Méditerranée Infection, Marseille, France
| | - Philippe Colson
- Aix-Marseille University, Institut de Recherche pour le Développement (IRD), Assistance Publique - Hôpitaux de Marseille (AP-HM), Microbes Evolution Phylogeny and Infections (MEPHI), Marseille, France
- IHU Méditerranée Infection, Marseille, France
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Claverie JM. Fundamental Difficulties Prevent the Reconstruction of the Deep Phylogeny of Viruses. Viruses 2020; 12:E1130. [PMID: 33036160 PMCID: PMC7600955 DOI: 10.3390/v12101130] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 10/01/2020] [Accepted: 10/03/2020] [Indexed: 12/11/2022] Open
Abstract
The extension of virology beyond its traditional medical, veterinary, or agricultural applications, now called environmental virology, has shown that viruses are both the most numerous and diverse biological entities on Earth. In particular, virus isolations from unicellular eukaryotic hosts (heterotrophic and photosynthetic protozoans) revealed numerous viral types previously unexpected in terms of virion structure, gene content, or mode of replication. Complemented by large-scale metagenomic analyses, these discoveries have rekindled interest in the enigma of the origin of viruses, for which a description encompassing all their diversity remains not available. Several laboratories have repeatedly tackled the deep reconstruction of the evolutionary history of viruses, using various methods of molecular phylogeny applied to the few shared "core" genes detected in certain virus groups (e.g., the Nucleocytoviricota). Beyond the practical difficulties of establishing reliable homology relationships from extremely divergent sequences, I present here conceptual arguments highlighting several fundamental limitations plaguing the reconstruction of the deep evolutionary history of viruses, and even more the identification of their unique or multiple origin(s). These arguments also underline the risk of establishing premature high level viral taxonomic classifications. Those limitations are direct consequences of the random mechanisms governing the reductive/retrogressive evolution of all obligate intracellular parasites.
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Affiliation(s)
- Jean-Michel Claverie
- Structural & Genomic Information Laboratory (IGS, UMR 7256), Mediterranean Institute of Microbiology (FR3479), Aix-Marseille University and CNRS, 13288 Marseille, France
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A Functional K + Channel from Tetraselmis Virus 1, a Member of the Mimiviridae. Viruses 2020; 12:v12101107. [PMID: 33003637 PMCID: PMC7650704 DOI: 10.3390/v12101107] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 09/25/2020] [Accepted: 09/25/2020] [Indexed: 12/05/2022] Open
Abstract
Potassium ion (K+) channels have been observed in diverse viruses that infect eukaryotic marine and freshwater algae. However, experimental evidence for functional K+ channels among these alga-infecting viruses has thus far been restricted to members of the family Phycodnaviridae, which are large, double-stranded DNA viruses within the phylum Nucleocytoviricota. Recent sequencing projects revealed that alga-infecting members of Mimiviridae, another family within this phylum, may also contain genes encoding K+ channels. Here we examine the structural features and the functional properties of putative K+ channels from four cultivated members of Mimiviridae. While all four proteins contain variations of the conserved selectivity filter sequence of K+ channels, structural prediction algorithms suggest that only two of them have the required number and position of two transmembrane domains that are present in all K+ channels. After in vitro translation and reconstitution of the four proteins in planar lipid bilayers, we confirmed that one of them, a 79 amino acid protein from the virus Tetraselmis virus 1 (TetV-1), forms a functional ion channel with a distinct selectivity for K+ over Na+ and a sensitivity to Ba2+. Thus, virus-encoded K+ channels are not limited to Phycodnaviridae but also occur in the members of Mimiviridae. The large sequence diversity among the viral K+ channels implies multiple events of lateral gene transfer.
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Coy SR, Gann ER, Papoulis SE, Holder ME, Ajami NJ, Petrosino JF, Zinser ER, Van Etten JL, Wilhelm SW. SMRT Sequencing of Paramecium Bursaria Chlorella Virus-1 Reveals Diverse Methylation Stability in Adenines Targeted by Restriction Modification Systems. Front Microbiol 2020; 11:887. [PMID: 32508769 PMCID: PMC7248222 DOI: 10.3389/fmicb.2020.00887] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 04/16/2020] [Indexed: 12/31/2022] Open
Abstract
Chloroviruses (family Phycodnaviridae) infect eukaryotic, freshwater, unicellular green algae. A unique feature of these viruses is an abundance of DNA methyltransferases, with isolates dedicating up to 4.5% of their protein coding potential to these genes. This diversity highlights just one of the long-standing values of the chlorovirus model system; where group-wide epigenomic characterization might begin to elucidate the function(s) of DNA methylation in large dsDNA viruses. We characterized DNA modifications in the prototype chlorovirus, PBCV-1, using single-molecule real time (SMRT) sequencing (aka PacBio). Results were compared to total available sites predicted in silico based on DNA sequence alone. SMRT-software detected N6-methyl-adenine (m6A) at GATC and CATG recognition sites, motifs previously shown to be targeted by PBCV-1 DNA methyltransferases M.CviAI and M. CviAII, respectively. At the same time, PacBio analyses indicated that 10.9% of the PBCV-1 genome had large interpulse duration ratio (ipdRatio) values, the primary metric for DNA modification identification. These events represent 20.6x more sites than can be accounted for by all available adenines in GATC and CATG motifs, suggesting base or backbone modifications other than methylation might be present. To define methylation stability, we cross-compared methylation status of each GATC and CATG sequence in three biological replicates and found ∼81% of sites were stably methylated, while ∼2% consistently lack methylation. The remaining 17% of sites were stochastically methylated. When methylation status was analyzed for both strands of each target, we show that palindromes existed in completely non-methylated states, fully-methylated states, or hemi-methylated states, though GATC sites more often lack methylation than CATG sequences. Given that both sequences are targeted by not just methyltransferases, but by restriction endonucleases that are together encoded by PBCV-1 as virus-originating restriction modification (RM) systems, there is strong selective pressure to modify all target sites. The finding that most instances of non-methylation are associated with hemi-methylation is congruent with observations that hemi-methylated palindromes are resistant to cleavage by restriction endonucleases. However, sites where hemi-methylation is conserved might represent a unique regulatory function for PBCV-1. This study serves as a baseline for future investigation into the epigenomics of chloroviruses and their giant virus relatives.
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Affiliation(s)
- Samantha R. Coy
- Department of Microbiology, The University of Tennessee, Knoxville, Knoxville, TN, United States
- BioSciences at Rice, Rice University, Houston, TX, United States
| | - Eric R. Gann
- Department of Microbiology, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Spiridon E. Papoulis
- Department of Microbiology, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Michael E. Holder
- Alkek Center for Metagenomics and Microbiome Research, Baylor College of Medicine, Houston, TX, United States
| | - Nadim J. Ajami
- Alkek Center for Metagenomics and Microbiome Research, Baylor College of Medicine, Houston, TX, United States
| | - Joseph F. Petrosino
- Alkek Center for Metagenomics and Microbiome Research, Baylor College of Medicine, Houston, TX, United States
| | - Erik R. Zinser
- Department of Microbiology, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - James L. Van Etten
- Department of Plant Pathology and the Nebraska Center for Virology, University of Nebraska, Lincoln, NE, United States
| | - Steven W. Wilhelm
- Department of Microbiology, The University of Tennessee, Knoxville, Knoxville, TN, United States
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Moniruzzaman M, Martinez-Gutierrez CA, Weinheimer AR, Aylward FO. Dynamic genome evolution and complex virocell metabolism of globally-distributed giant viruses. Nat Commun 2020; 11:1710. [PMID: 32249765 PMCID: PMC7136201 DOI: 10.1038/s41467-020-15507-2] [Citation(s) in RCA: 107] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 03/09/2020] [Indexed: 01/11/2023] Open
Abstract
The discovery of eukaryotic giant viruses has transformed our understanding of the limits of viral complexity, but the extent of their encoded metabolic diversity remains unclear. Here we generate 501 metagenome-assembled genomes of Nucleo-Cytoplasmic Large DNA Viruses (NCLDV) from environments around the globe, and analyze their encoded functional capacity. We report a remarkable diversity of metabolic genes in widespread giant viruses, including many involved in nutrient uptake, light harvesting, and nitrogen metabolism. Surprisingly, numerous NCLDV encode the components of glycolysis and the TCA cycle, suggesting that they can re-program fundamental aspects of their host's central carbon metabolism. Our phylogenetic analysis of NCLDV metabolic genes and their cellular homologs reveals distinct clustering of viral sequences into divergent clades, indicating that these genes are virus-specific and were acquired in the distant past. Overall our findings reveal that giant viruses encode complex metabolic capabilities with evolutionary histories largely independent of cellular life, strongly implicating them as important drivers of global biogeochemical cycles.
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Affiliation(s)
| | | | - Alaina R Weinheimer
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, 24061, USA
| | - Frank O Aylward
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, 24061, USA.
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43
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An Optimized Metabarcoding Method for Mimiviridae. Microorganisms 2020; 8:microorganisms8040506. [PMID: 32252306 PMCID: PMC7254495 DOI: 10.3390/microorganisms8040506] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 03/27/2020] [Accepted: 03/31/2020] [Indexed: 12/13/2022] Open
Abstract
Mimiviridae is a group of viruses with large genomes and virions. Ecological relevance of Mimiviridae in marine environments has been increasingly recognized through the discoveries of novel isolates and metagenomic studies. To facilitate ecological profiling of Mimiviridae, we previously proposed a meta-barcoding approach based on 82 degenerate primer pairs (i.e., MEGAPRIMER) targeting the DNA polymerase gene of Mimiviridae. The method detected a larger number of operational taxonomic units (OTUs) in environmental samples than previous methods. However, it required large quantities of DNA and was laborious due to the use of individual primer pairs. Here, we examined coastal seawater samples using varying PCR conditions and purification protocols to streamline the MEGAPRIMER method. Mixing primer pairs in "cocktails" reduced the required amount of environmental DNA by 90%, while reproducing the results obtained by the original protocol. We compared the results obtained by the meta-barcoding approach with quantifications using qPCR for selected OTUs. This revealed possible amplification biases among different OTUs, but the frequency profiles for individual OTUs across multiple samples were similar to those obtained by qPCR. We anticipate that the newly developed MEGAPRIMER protocols will be useful for ecological investigation of Mimiviridae in a larger set of environmental samples.
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Schulz F, Roux S, Paez-Espino D, Jungbluth S, Walsh DA, Denef VJ, McMahon KD, Konstantinidis KT, Eloe-Fadrosh EA, Kyrpides NC, Woyke T. Giant virus diversity and host interactions through global metagenomics. Nature 2020; 578:432-436. [PMID: 31968354 PMCID: PMC7162819 DOI: 10.1038/s41586-020-1957-x] [Citation(s) in RCA: 148] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 01/09/2020] [Indexed: 12/11/2022]
Abstract
Our current knowledge about nucleocytoplasmic large DNA viruses (NCLDVs) is largely derived from viral isolates that are co-cultivated with protists and algae. Here we reconstructed 2,074 NCLDV genomes from sampling sites across the globe by building on the rapidly increasing amount of publicly available metagenome data. This led to an 11-fold increase in phylogenetic diversity and a parallel 10-fold expansion in functional diversity. Analysis of 58,023 major capsid proteins from large and giant viruses using metagenomic data revealed the global distribution patterns and cosmopolitan nature of these viruses. The discovered viral genomes encoded a wide range of proteins with putative roles in photosynthesis and diverse substrate transport processes, indicating that host reprogramming is probably a common strategy in the NCLDVs. Furthermore, inferences of horizontal gene transfer connected viral lineages to diverse eukaryotic hosts. We anticipate that the global diversity of NCLDVs that we describe here will establish giant viruses-which are associated with most major eukaryotic lineages-as important players in ecosystems across Earth's biomes.
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Affiliation(s)
- Frederik Schulz
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
| | - Simon Roux
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - David Paez-Espino
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Sean Jungbluth
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - David A Walsh
- Groupe de recherche interuniversitaire en limnologie, Department of Biology, Concordia University, Montréal, Québec, Canada
| | - Vincent J Denef
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, USA
| | - Katherine D McMahon
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA
- Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | | | - Emiley A Eloe-Fadrosh
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Nikos C Kyrpides
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Tanja Woyke
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
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45
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Zimmerman AE, Howard-Varona C, Needham DM, John SG, Worden AZ, Sullivan MB, Waldbauer JR, Coleman ML. Metabolic and biogeochemical consequences of viral infection in aquatic ecosystems. Nat Rev Microbiol 2019; 18:21-34. [PMID: 31690825 DOI: 10.1038/s41579-019-0270-x] [Citation(s) in RCA: 158] [Impact Index Per Article: 31.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/09/2019] [Indexed: 12/23/2022]
Abstract
Ecosystems are controlled by 'bottom-up' (resources) and 'top-down' (predation) forces. Viral infection is now recognized as a ubiquitous top-down control of microbial growth across ecosystems but, at the same time, cell death by viral predation influences, and is influenced by, resource availability. In this Review, we discuss recent advances in understanding the biogeochemical impact of viruses, focusing on how metabolic reprogramming of host cells during lytic viral infection alters the flow of energy and nutrients in aquatic ecosystems. Our synthesis revealed several emerging themes. First, viral infection transforms host metabolism, in part through virus-encoded metabolic genes; the functions performed by these genes appear to alleviate energetic and biosynthetic bottlenecks to viral production. Second, viral infection depends on the physiological state of the host cell and on environmental conditions, which are challenging to replicate in the laboratory. Last, metabolic reprogramming of infected cells and viral lysis alter nutrient cycling and carbon export in the oceans, although the net impacts remain uncertain. This Review highlights the need for understanding viral infection dynamics in realistic physiological and environmental contexts to better predict their biogeochemical consequences.
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Affiliation(s)
- Amy E Zimmerman
- Department of the Geophysical Sciences, University of Chicago, Chicago, IL, USA
| | | | - David M Needham
- Monterey Bay Aquarium Research Institute, Moss Landing, CA, USA
| | - Seth G John
- Department of Earth Science, University of Southern California, Los Angeles, CA, USA
| | - Alexandra Z Worden
- Monterey Bay Aquarium Research Institute, Moss Landing, CA, USA.,Ocean EcoSystems Biology Unit, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
| | - Matthew B Sullivan
- Department of Microbiology, Ohio State University, Columbus, OH, USA.,Department of Civil, Environmental and Geodetic Engineering, Ohio State University, Columbus, OH, USA
| | - Jacob R Waldbauer
- Department of the Geophysical Sciences, University of Chicago, Chicago, IL, USA
| | - Maureen L Coleman
- Department of the Geophysical Sciences, University of Chicago, Chicago, IL, USA.
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Abstract
Since the discovery of mimivirus, numerous giant viruses associated with free-living amoebae have been described. The genome of giant viruses can be more than 2.5 megabases, and virus particles can exceed the size of many bacteria. The unexpected characteristics of these viruses have made them intriguing research targets and, as a result, studies focusing on their interactions with their amoeba host have gained increased attention. Studies have shown that giant viruses can establish host-pathogen interactions, which have not been previously demonstrated, including the unprecedented interaction with a new group of small viruses, called virophages, that parasitize their viral factories. In this brief review, we present recent advances in virophage-giant virus-host interactions and highlight selected studies involving interactions between giant viruses and amoebae. These unprecedented interactions involve the giant viruses mimivirus, marseillevirus, tupanviruses and faustovirus, all of which modulate the amoeba environment, affecting both their replication and their spread to new hosts.
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Needham DM, Poirier C, Hehenberger E, Jiménez V, Swalwell JE, Santoro AE, Worden AZ. Targeted metagenomic recovery of four divergent viruses reveals shared and distinctive characteristics of giant viruses of marine eukaryotes. Philos Trans R Soc Lond B Biol Sci 2019; 374:20190086. [PMID: 31587639 PMCID: PMC6792449 DOI: 10.1098/rstb.2019.0086] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Giant viruses have remarkable genomic repertoires—blurring the line with cellular life—and act as top–down controls of eukaryotic plankton. However, to date only six cultured giant virus genomes are available from the pelagic ocean. We used at-sea flow cytometry with staining and sorting designed to target wild predatory eukaryotes, followed by DNA sequencing and assembly, to recover novel giant viruses from the Pacific Ocean. We retrieved four ‘PacV’ partial genomes that range from 421 to 1605 Kb, with 13 contigs on average, including the largest marine viral genomic assembly reported to date. Phylogenetic analyses indicate that three of the new viruses span a clade with deep-branching members of giant Mimiviridae, incorporating the Cafeteria roenbergensis virus, the uncultivated terrestrial Faunusvirus, one PacV from a choanoflagellate and two PacV with unclear hosts. The fourth virus, oPacV-421, is phylogenetically related to viruses that infect haptophyte algae. About half the predicted proteins in each PacV have no matches in NCBI nr (e-value < 10−5), totalling 1735 previously unknown proteins; the closest affiliations of the other proteins were evenly distributed across eukaryotes, prokaryotes and viruses of eukaryotes. The PacVs encode many translational proteins and two encode eukaryotic-like proteins from the Rh family of the ammonium transporter superfamily, likely influencing the uptake of nitrogen during infection. cPacV-1605 encodes a microbial viral rhodopsin (VirR) and the biosynthesis pathway for the required chromophore, the second finding of a choanoflagellate-associated virus that encodes these genes. In co-collected metatranscriptomes, 85% of cPacV-1605 genes were expressed, with capsids, heat shock proteins and proteases among the most highly expressed. Based on orthologue presence–absence patterns across the PacVs and other eukaryotic viruses, we posit the observed viral groupings are connected to host lifestyles as heterotrophs or phototrophs. This article is part of a discussion meeting issue ‘Single cell ecology’.
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Affiliation(s)
- David M Needham
- Monterey Bay Aquarium Research Institute, Moss Landing, CA 95039, USA
| | - Camille Poirier
- Monterey Bay Aquarium Research Institute, Moss Landing, CA 95039, USA.,Ocean EcoSystems Biology Unit, RD3, GEOMAR Helmholtz Centre for Ocean Research, Kiel, 24105, Germany
| | - Elisabeth Hehenberger
- Monterey Bay Aquarium Research Institute, Moss Landing, CA 95039, USA.,Ocean EcoSystems Biology Unit, RD3, GEOMAR Helmholtz Centre for Ocean Research, Kiel, 24105, Germany
| | - Valeria Jiménez
- Monterey Bay Aquarium Research Institute, Moss Landing, CA 95039, USA
| | - Jarred E Swalwell
- Monterey Bay Aquarium Research Institute, Moss Landing, CA 95039, USA.,School of Oceanography, University of Washington, Box 357940, Seattle, WA 98195, USA
| | - Alyson E Santoro
- Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, CA 93106, USA
| | - Alexandra Z Worden
- Monterey Bay Aquarium Research Institute, Moss Landing, CA 95039, USA.,Ocean EcoSystems Biology Unit, RD3, GEOMAR Helmholtz Centre for Ocean Research, Kiel, 24105, Germany
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A distinct lineage of giant viruses brings a rhodopsin photosystem to unicellular marine predators. Proc Natl Acad Sci U S A 2019; 116:20574-20583. [PMID: 31548428 PMCID: PMC6789865 DOI: 10.1073/pnas.1907517116] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Giant viruses are remarkable for their large genomes, often rivaling those of small bacteria, and for having genes thought exclusive to cellular life. Most isolated to date infect nonmarine protists, leaving their strategies and prevalence in marine environments largely unknown. Using eukaryotic single-cell metagenomics in the Pacific, we discovered a Mimiviridae lineage of giant viruses, which infects choanoflagellates, widespread protistan predators related to metazoans. The ChoanoVirus genomes are the largest yet from pelagic ecosystems, with 442 of 862 predicted proteins lacking known homologs. They are enriched in enzymes for modifying organic compounds, including degradation of chitin, an abundant polysaccharide in oceans, and they encode 3 divergent type-1 rhodopsins (VirR) with distinct evolutionary histories from those that capture sunlight in cellular organisms. One (VirRDTS) is similar to the only other putative rhodopsin from a virus (PgV) with a known host (a marine alga). Unlike the algal virus, ChoanoViruses encode the entire pigment biosynthesis pathway and cleavage enzyme for producing the required chromophore, retinal. We demonstrate that the rhodopsin shared by ChoanoViruses and PgV binds retinal and pumps protons. Moreover, our 1.65-Å resolved VirRDTS crystal structure and mutational analyses exposed differences from previously characterized type-1 rhodopsins, all of which come from cellular organisms. Multiple VirR types are present in metagenomes from across surface oceans, where they are correlated with and nearly as abundant as a canonical marker gene from Mimiviridae Our findings indicate that light-dependent energy transfer systems are likely common components of giant viruses of photosynthetic and phagotrophic unicellular marine eukaryotes.
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Mougari S, Sahmi-Bounsiar D, Levasseur A, Colson P, La Scola B. Virophages of Giant Viruses: An Update at Eleven. Viruses 2019; 11:v11080733. [PMID: 31398856 PMCID: PMC6723459 DOI: 10.3390/v11080733] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 07/31/2019] [Accepted: 08/02/2019] [Indexed: 12/19/2022] Open
Abstract
The last decade has been marked by two eminent discoveries that have changed our perception of the virology field: The discovery of giant viruses and a distinct new class of viral agents that parasitize their viral factories, the virophages. Coculture and metagenomics have actively contributed to the expansion of the virophage family by isolating dozens of new members. This increase in the body of data on virophage not only revealed the diversity of the virophage group, but also the relevant ecological impact of these small viruses and their potential role in the dynamics of the microbial network. In addition, the isolation of virophages has led us to discover previously unknown features displayed by their host viruses and cells. In this review, we present an update of all the knowledge on the isolation, biology, genomics, and morphological features of the virophages, a decade after the discovery of their first member, the Sputnik virophage. We discuss their parasitic lifestyle as bona fide viruses of the giant virus factories, genetic parasites of their genomes, and then their role as a key component or target for some host defense mechanisms during the tripartite virophage–giant virus–host cell interaction. We also present the latest advances regarding their origin, classification, and definition that have been widely discussed.
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Affiliation(s)
- Said Mougari
- Aix-Marseille Université, Institut de Recherche pour le Développement (IRD), Assistance Publique - Hôpitaux de Marseille (AP-HM), Microbes Evolution Phylogeny and Infections (MEPHI), 27 boulevard Jean Moulin, 13005 Marseille, France
- Institut Hospitalo-Universitaire (IHU) Méditerranée Infection, 19-21 boulevard Jean Moulin, 13005 Marseille, France
| | - Dehia Sahmi-Bounsiar
- Aix-Marseille Université, Institut de Recherche pour le Développement (IRD), Assistance Publique - Hôpitaux de Marseille (AP-HM), Microbes Evolution Phylogeny and Infections (MEPHI), 27 boulevard Jean Moulin, 13005 Marseille, France
- Institut Hospitalo-Universitaire (IHU) Méditerranée Infection, 19-21 boulevard Jean Moulin, 13005 Marseille, France
| | - Anthony Levasseur
- Aix-Marseille Université, Institut de Recherche pour le Développement (IRD), Assistance Publique - Hôpitaux de Marseille (AP-HM), Microbes Evolution Phylogeny and Infections (MEPHI), 27 boulevard Jean Moulin, 13005 Marseille, France
- Institut Hospitalo-Universitaire (IHU) Méditerranée Infection, 19-21 boulevard Jean Moulin, 13005 Marseille, France
| | - Philippe Colson
- Aix-Marseille Université, Institut de Recherche pour le Développement (IRD), Assistance Publique - Hôpitaux de Marseille (AP-HM), Microbes Evolution Phylogeny and Infections (MEPHI), 27 boulevard Jean Moulin, 13005 Marseille, France.
- Institut Hospitalo-Universitaire (IHU) Méditerranée Infection, 19-21 boulevard Jean Moulin, 13005 Marseille, France.
| | - Bernard La Scola
- Aix-Marseille Université, Institut de Recherche pour le Développement (IRD), Assistance Publique - Hôpitaux de Marseille (AP-HM), Microbes Evolution Phylogeny and Infections (MEPHI), 27 boulevard Jean Moulin, 13005 Marseille, France.
- Institut Hospitalo-Universitaire (IHU) Méditerranée Infection, 19-21 boulevard Jean Moulin, 13005 Marseille, France.
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Li Y, Endo H, Gotoh Y, Watai H, Ogawa N, Blanc-Mathieu R, Yoshida T, Ogata H. The Earth Is Small for "Leviathans": Long Distance Dispersal of Giant Viruses across Aquatic Environments. Microbes Environ 2019; 34:334-339. [PMID: 31378760 PMCID: PMC6759346 DOI: 10.1264/jsme2.me19037] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Giant viruses of ‘Megaviridae’ have the ability to widely disperse around the globe. We herein examined ‘Megaviridae’ communities in four distinct aquatic environments (coastal and offshore seawater, brackish water, and hot spring freshwater), which are distantly located from each other (between 74 and 1,765 km), using a meta-barcoding method. We identified between 593 and 3,627 OTUs in each sample. Some OTUs were detected in all five samples tested as well as in many of the Tara Oceans metagenomes, suggesting the existence of viruses of this family in a wide range of habitats and the ability to circulate on the planet.
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Affiliation(s)
- Yanze Li
- Institute for Chemical Research, Kyoto University
| | - Hisashi Endo
- Institute for Chemical Research, Kyoto University
| | - Yasuhiro Gotoh
- Department of Bacteriology, Faculty of Medical Sciences, Kyushu University
| | | | - Nana Ogawa
- Graduate School of Agriculture, Kyoto University
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