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Koonin EV, Fischer MG, Kuhn JH, Krupovic M. The polinton-like supergroup of viruses: evolution, molecular biology, and taxonomy. Microbiol Mol Biol Rev 2024; 88:e0008623. [PMID: 39023254 PMCID: PMC11426020 DOI: 10.1128/mmbr.00086-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2024] Open
Abstract
SUMMARYPolintons are 15-20 kb-long self-synthesizing transposons that are widespread in eukaryotic, and in particular protist, genomes. Apart from a transposase and a protein-primed DNA polymerase, polintons encode homologs of major and minor jelly-roll capsid proteins, DNA-packaging ATPases, and proteases involved in capsid maturation of diverse eukaryotic viruses of kingdom Bamfordvirae. Given the conservation of these structural and morphogenetic proteins among polintons, these elements are predicted to alternate between transposon and viral lifestyles and, although virions have thus far not been detected, are classified as viruses (class Polintoviricetes) in the phylum Preplasmiviricota. Related to polintoviricetes are vertebrate adenovirids; unclassified polinton-like viruses (PLVs) identified in various environments or integrated into diverse protist genomes; virophages (Maveriviricetes), which are part of tripartite hyperparasitic systems including protist hosts and giant viruses; and capsid-less derivatives, such as cytoplasmic linear DNA plasmids of fungi and transpovirons. Phylogenomic analysis indicates that the polinton-like supergroup of viruses bridges bacterial tectivirids (preplasmiviricot class Tectiliviricetes) to the phylum Nucleocytoviricota that includes large and giant eukaryotic DNA viruses. Comparative structural analysis of proteins encoded by polinton-like viruses led to the discovery of previously undetected functional domains, such as terminal proteins and distinct proteases implicated in DNA polymerase processing, and clarified the evolutionary relationships within Polintoviricetes. Here, we leverage these insights into the evolution of the polinton-like supergroup to develop an amended megataxonomy that groups Polintoviricetes, PLVs (new class 'Aquintoviricetes'), and virophages (renamed class 'Virophaviricetes') together with Adenoviridae (new class 'Pharingeaviricetes') in a preplasmiviricot subphylum 'Polisuviricotina' sister to a subphylum including Tectiliviricetes ('Prepoliviricotina').
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Affiliation(s)
- Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, USA
| | - Matthias G Fischer
- Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Jens H Kuhn
- Integrated Research Facility at Fort Detrick, Division of Clinical Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, Maryland, USA
| | - Mart Krupovic
- Institut Pasteur, Université Paris Cité, Archaeal Virology Unit, Paris, France
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2
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Nunes GHP, Oliveira JDS, Essus VA, Guimarães AJ, Pontes B, Cortines JR. Cytopathic effects in Mimivirus infection: understanding the kinetics of virus-cell interaction. Mem Inst Oswaldo Cruz 2024; 119:e230186. [PMID: 39045993 DOI: 10.1590/0074-02760230186] [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: 09/09/2023] [Accepted: 05/10/2024] [Indexed: 07/25/2024] Open
Abstract
BACKGROUND Giant viruses have brought new insights into different aspects of virus-cell interactions. The resulting cytopathic effects from these interactions are one of the main aspects of infection assessment in a laboratory routine, mainly reflecting on the morphological features of an infected cell. OBJECTIVES In this work, we follow the entire kinetics of the cytopathic effect in cells infected by viruses of the Mimiviridae family, spatiotemporally quantifying typical features such as cell roundness, loss of motility, decrease in cell area and cell lysis. METHODS Infections by Acanthamoeba polyphaga mimivirus (APMV), Tupanvirus (TPV) and M4 were carried out at multiplicity of infection (MOI) 1 and MOI 10 in Acanthamoeba castellanii. Monitoring of infections was carried out using time lapse microscopy for up to 72 hours. The images were analyzed using ImageJ software. FINDINGS The data obtained indicate that APMV is the slowest virus in inducing the cytopathic effects of rounding, decrease in cell area, mobility and cell lysis. However, it is the only virus whose MOI increase accelerates the lysis process of infected cells. In turn, TPV and M4 rapidly induce morphological and behavioral changes. MAIN CONCLUSIONS Our results indicate that mimiviruses induce different temporal responses within the host cell and that it is possible to use these kinetic data to facilitate the understanding of infection by these viruses.
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Affiliation(s)
- Gabriel Henrique Pereira Nunes
- Universidade Federal do Rio de Janeiro, Instituto de Microbiologia Paulo de Góes, Departamento de Virologia, Laboratório de Virologia e Espectrometria de Massas, Rio de Janeiro, RJ, Brasil
| | - Juliana Dos Santos Oliveira
- Universidade Federal do Rio de Janeiro, Instituto de Microbiologia Paulo de Góes, Departamento de Virologia, Laboratório de Virologia e Espectrometria de Massas, Rio de Janeiro, RJ, Brasil
| | - Victor Alejandro Essus
- Universidade Federal do Rio de Janeiro, Instituto de Microbiologia Paulo de Góes, Departamento de Virologia, Laboratório de Virologia e Espectrometria de Massas, Rio de Janeiro, RJ, Brasil
| | - Allan J Guimarães
- Universidade Federal Fluminense, Instituto Biomédico, Departamento de Microbiologia e Parasitologia, Niterói, RJ, Brasil
| | - Bruno Pontes
- Universidade Federal do Rio de Janeiro, Instituto de Ciências Biomédicas & Centro Nacional de Biologia Estrutural e Bioimagem, Rio de Janeiro, RJ, Brasil
| | - Juliana Reis Cortines
- Universidade Federal do Rio de Janeiro, Instituto de Microbiologia Paulo de Góes, Departamento de Virologia, Laboratório de Virologia e Espectrometria de Massas, Rio de Janeiro, RJ, Brasil
- University of Connecticut, Department of Chemistry, Storrs, CT, USA
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3
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Tokarz-Deptuła B, Chrzanowska S, Baraniecki Ł, Gurgacz N, Stosik M, Sobolewski J, Deptuła W. Virophages, Satellite Viruses, Virophage Replication and Its Effects and Virophage Defence Mechanisms for Giant Virus Hosts and Giant Virus Defence Systems against Virophages. Int J Mol Sci 2024; 25:5878. [PMID: 38892066 PMCID: PMC11172284 DOI: 10.3390/ijms25115878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 05/22/2024] [Accepted: 05/24/2024] [Indexed: 06/21/2024] Open
Abstract
In this paper, the characteristics of 40 so far described virophages-parasites of giant viruses-are given, and the similarities and differences between virophages and satellite viruses, which also, like virophages, require helper viruses for replication, are described. The replication of virophages taking place at a specific site-the viral particle factory of giant viruses-and its consequences are presented, and the defence mechanisms of virophages for giant virus hosts, as a protective action for giant virus hosts-protozoa and algae-are approximated. The defence systems of giant viruses against virophages were also presented, which are similar to the CRISPR/Cas defence system found in bacteria and in Archea. These facts, and related to the very specific biological features of virophages (specific site of replication, specific mechanisms of their defensive effects for giant virus hosts, defence systems in giant viruses against virophages), indicate that virophages, and their host giant viruses, are biological objects, forming a 'novelty' in biology.
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Affiliation(s)
| | - Sara Chrzanowska
- Institute of Biology, University of Szczecin, 71-412 Szczecin, Poland (Ł.B.)
| | - Łukasz Baraniecki
- Institute of Biology, University of Szczecin, 71-412 Szczecin, Poland (Ł.B.)
| | - Natalia Gurgacz
- Institute of Biology, University of Szczecin, 71-412 Szczecin, Poland (Ł.B.)
| | - Michał Stosik
- Institute of Biological Science, Faculty of Biological Sciences, University of Zielona Góra, 65-516 Zielona Góra, Poland;
| | - Jarosław Sobolewski
- Institute of Veterinary Medicine, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University in Toruń, 87-100 Toruń, Poland;
| | - Wiesław Deptuła
- Institute of Veterinary Medicine, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University in Toruń, 87-100 Toruń, Poland;
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4
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Barth ZK, Aylward FO. March of the proviruses. Proc Natl Acad Sci U S A 2024; 121:e2402541121. [PMID: 38527209 PMCID: PMC10998573 DOI: 10.1073/pnas.2402541121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/27/2024] Open
Affiliation(s)
- Zachary K. Barth
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA24061
| | - Frank O. Aylward
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA24061
- Center for Emerging, Zoonotic, and Arthropod-Borne Pathogens, Virginia Tech, Blacksburg, VA24061
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5
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Potapov SA, Belykh OI. Virophages Found in Viromes from Lake Baikal. Biomolecules 2023; 13:1773. [PMID: 38136644 PMCID: PMC10741620 DOI: 10.3390/biom13121773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 12/04/2023] [Accepted: 12/06/2023] [Indexed: 12/24/2023] Open
Abstract
In this study, a previously little-studied group of viruses-virophages-was searched for and identified in the viromes of the ancient oligotrophic Lake Baikal. Virophages are small dsDNA viruses that parasitize giant viruses (e.g., Mimiviridae), which in turn affect unicellular eukaryotes. We analyzed eight viromes obtained from the deep-water areas of three basins of Lake Baikal and the shallow-water strait Maloye More in different seasons. The sequences of virophages were revealed in all viromes and were dominant after bacteriophages and algal viruses. Sixteen putative complete genomes of virophages were assembled, all of which contained four conserved genes encoding major capsid protein (MCP), minor capsid protein (mCP), maturation cysteine protease (PRO), and FtsK-HerA family DNA-packaging ATPase (ATPase). The MCP-based cluster analysis showed a sequence separation according to seasons, and a dependence on the geographical localization was not detected.
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Affiliation(s)
- Sergey Anatoljevich Potapov
- Limnological Institute Siberian Branch of the Russian Academy of Sciences, Ulan-Batorskaya 3, Irkutsk 664033, Russia;
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Wu Z, Chu T, Sheng Y, Yu Y, Wang Y. Diversity, Relationship, and Distribution of Virophages and Large Algal Viruses in Global Ocean Viromes. Viruses 2023; 15:1582. [PMID: 37515268 PMCID: PMC10385804 DOI: 10.3390/v15071582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 07/10/2023] [Accepted: 07/12/2023] [Indexed: 07/30/2023] Open
Abstract
Virophages are a group of small double-stranded DNA viruses that replicate and proliferate with the help of the viral factory of large host viruses. They are widely distributed in aquatic environments but are more abundant in freshwater ecosystems. Here, we mined the Global Ocean Viromes 2.0 (GOV 2.0) dataset for the diversity, distribution, and association of virophages and their potential host large viruses in marine environments. We identified 94 virophage sequences (>5 kbp in length), of which eight were complete genomes. The MCP phylogenetic tree showed that the GOV virophages were widely distributed on the global virophage tree but relatively clustered on three major branches. The gene-sharing network divided GOV virophages into 21 outliers, 2 overlaps, and 14 viral clusters, of which 4 consisted of only the GOV virophages. We also identified 45 large virus sequences, 8 of which were >100 kbp in length and possibly involved in cell-virus-virophage (C-V-v) trisome relationships. The potential eukaryotic hosts of these eight large viruses and the eight virophages with their complete genomes identified are likely to be algae, based on comparative genomic analysis. Both homologous gene and codon usage analyses support a possible interaction between a virophage (GOVv18) and a large algal virus (GOVLV1). These results indicate that diverse and novel virophages and large viruses are widespread in global marine environments, suggesting their important roles and the presence of complicated unknown C-V-v relationships in marine ecosystems.
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Affiliation(s)
- Zhenqi Wu
- College of Food Science and Technology, Shanghai Ocean University, Shanghai 201304, China
| | - Ting Chu
- College of Food Science and Technology, Shanghai Ocean University, Shanghai 201304, China
| | - Yijian Sheng
- College of Food Science and Technology, Shanghai Ocean University, Shanghai 201304, China
| | - Yongxin Yu
- College of Food Science and Technology, Shanghai Ocean University, Shanghai 201304, China
- Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation (Shanghai), Ministry of Agriculture and Rural Affairs, Shanghai 201304, China
| | - Yongjie Wang
- College of Food Science and Technology, Shanghai Ocean University, Shanghai 201304, China
- Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation (Shanghai), Ministry of Agriculture and Rural Affairs, Shanghai 201304, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266000, China
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7
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Tokarz-Deptuła B, Chrzanowska S, Gurgacz N, Stosik M, Deptuła W. Virophages-Known and Unknown Facts. Viruses 2023; 15:1321. [PMID: 37376621 PMCID: PMC10301787 DOI: 10.3390/v15061321] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 05/31/2023] [Accepted: 05/31/2023] [Indexed: 06/29/2023] Open
Abstract
The paper presents virophages, which, like their host, giant viruses, are "new" infectious agents whose role in nature, including mammalian health, is important. Virophages, along with their protozoan and algal hosts, are found in fresh inland waters and oceanic and marine waters, including thermal waters and deep-sea vents, as well as in soil, plants, and in humans and animals (ruminants). Representing "superparasitism", almost all of the 39 described virophages (except Zamilon) interact negatively with giant viruses by affecting their replication and morphogenesis and their "adaptive immunity". This causes them to become regulators and, at the same time, defenders of the host of giant viruses protozoa and algae, which are organisms that determine the homeostasis of the aquatic environment. They are classified in the family Lavidaviridae with two genus (Sputnikovirus, Mavirus). However, in 2023, a proposal was presented that they should form the class Maveriviricetes, with four orders and seven families. Their specific structure, including their microsatellite (SSR-Simple Sequence Repeats) and the CVV (cell-virus-virophage, or transpovirion) system described with them, as well as their function, makes them, together with the biological features of giant viruses, form the basis for discussing the existence of a fourth domain in addition to Bacteria, Archaea, and Eukaryota. The paper also presents the hypothetical possibility of using them as a vector for vaccine antigens.
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Affiliation(s)
| | - Sara Chrzanowska
- Institute of Biology, University of Szczecin, 71-412 Szczecin, Poland
| | - Natalia Gurgacz
- Institute of Biology, University of Szczecin, 71-412 Szczecin, Poland
| | - Michał Stosik
- Institute of Biological Science, Faculty of Biological Sciences, University of Zielona Góra, 65-417 Zielona Góra, Poland
| | - Wiesław Deptuła
- Institute of Veterinary Medicine, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University of Toruń, 87-100 Toruń, Poland
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Kouidhi S, Zidi O, Belkhiria Z, Rais H, Ayadi A, Ben Ayed F, Mosbah A, Cherif A, El Gaaied ABA. Gut microbiota, an emergent target to shape the efficiency of cancer therapy. EXPLORATION OF TARGETED ANTI-TUMOR THERAPY 2023; 4:240-265. [PMID: 37205307 PMCID: PMC10185446 DOI: 10.37349/etat.2023.00132] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Accepted: 01/04/2023] [Indexed: 05/21/2023] Open
Abstract
It is now well-acknowledged that microbiota has a profound influence on both human health and illness. The gut microbiota has recently come to light as a crucial element that influences cancer through a variety of mechanisms. The connections between the microbiome and cancer therapy are further highlighted by a number of preclinical and clinical evidence, suggesting that these complicated interactions may vary by cancer type, treatment, or even by tumor stage. The paradoxical relationship between gut microbiota and cancer therapies is that in some cancers, the gut microbiota may be necessary to maintain therapeutic efficacy, whereas, in other cancers, gut microbiota depletion significantly increases efficacy. Actually, mounting research has shown that the gut microbiota plays a crucial role in regulating the host immune response and boosting the efficacy of anticancer medications like chemotherapy and immunotherapy. Therefore, gut microbiota modulation, which aims to restore gut microbial balance, is a viable technique for cancer prevention and therapy given the expanding understanding of how the gut microbiome regulates treatment response and contributes to carcinogenesis. This review will provide an outline of the gut microbiota's role in health and disease, along with a summary of the most recent research on how it may influence the effectiveness of various anticancer medicines and affect the growth of cancer. This study will next cover the newly developed microbiota-targeting strategies including prebiotics, probiotics, and fecal microbiota transplantation (FMT) to enhance anticancer therapy effectiveness, given its significance.
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Affiliation(s)
- Soumaya Kouidhi
- Laboratory BVBGR-LR11ES31, Biotechnopole Sidi Thabet, University Manouba, ISBST, Ariana 2020, Tunisia
- Association Tunisienne de Lutte contre le Cancer (ATCC), Tunis, Tunisia
| | - Oumaima Zidi
- Laboratory BVBGR-LR11ES31, Biotechnopole Sidi Thabet, University Manouba, ISBST, Ariana 2020, Tunisia
- Department of Biologu, Faculty of Sciences of Tunis, University of Tunis El Manar, Tunis 1068, Tunisia
| | | | - Henda Rais
- Association Tunisienne de Lutte contre le Cancer (ATCC), Tunis, Tunisia
- Service d’Oncologie Médicale, Hôpital Salah-Azaïz, Tunis 1006, Tunisia
| | - Aida Ayadi
- Department of Pathology, Abderrahman Mami Hospital, University of Tunis El Manar, Ariana 2080, Tunisia
| | - Farhat Ben Ayed
- Association Tunisienne de Lutte contre le Cancer (ATCC), Tunis, Tunisia
| | - Amor Mosbah
- Laboratory BVBGR-LR11ES31, Biotechnopole Sidi Thabet, University Manouba, ISBST, Ariana 2020, Tunisia
| | - Ameur Cherif
- Laboratory BVBGR-LR11ES31, Biotechnopole Sidi Thabet, University Manouba, ISBST, Ariana 2020, Tunisia
| | - Amel Ben Ammar El Gaaied
- Laboratory of Genetics, Immunology and Human Pathology, Department of Biology, Faculty of Sciences of Tunis, University of Tunis El Manar, Tunis 1068, Tunisia
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Roitman S, Rozenberg A, Lavy T, Brussaard CPD, Kleifeld O, Béjà O. Isolation and infection cycle of a polinton-like virus virophage in an abundant marine alga. Nat Microbiol 2023; 8:332-346. [PMID: 36702941 DOI: 10.1038/s41564-022-01305-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 12/13/2022] [Indexed: 01/27/2023]
Abstract
Virophages are small double stranded DNA (dsDNA) viruses that can only replicate in a host by co-infecting with another virus. Marine algae are commonly associated with virophage-like elements such as Polinton-like viruses (PLVs) that remain largely uncharacterized. Here we isolated a PLV that co-infects the alga Phaeocystis globosa with the Phaeocystis globosa virus-14T (PgV-14T), a close relative of the "Phaeocystis globosa virus-virophage" genomic sequence. We name this PLV 'Gezel-14T. Gezel is phylogenetically distinct from the Lavidaviridae family where all known virophages belong. Gezel-14T co-infection decreases the fitness of its viral host by reducing burst sizes of PgV-14T, yet insufficiently to spare the cellular host population. Genomic screens show Gezel-14T-like PLVs integrated into Phaeocystis genomes, suggesting that these widespread viruses are capable of integration into cellular host genomes. This system presents an opportunity to better understand the evolution of eukaryotic dsDNA viruses as well as the complex dynamics and implications of viral parasitism.
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Affiliation(s)
- Sheila Roitman
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, Israel.
| | - Andrey Rozenberg
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, Israel
| | - Tali Lavy
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, Israel
| | - 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
| | - Oded Kleifeld
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, Israel
| | - Oded Béjà
- Faculty of Biology, Technion - Israel Institute of Technology, Haifa, Israel.
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Dutta D, Ravichandiran V, Sukla S. Virophages: association with human diseases and their predicted role as virus killers. Pathog Dis 2021; 79:6380487. [PMID: 34601577 DOI: 10.1093/femspd/ftab049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 09/27/2021] [Indexed: 11/13/2022] Open
Abstract
The fascinating discovery of the first giant virus, Acanthamoeba polyphaga mimivirus (APMV), belonging to the family Mimiviridae in 2008, and its associated virophage, Sputnik, have left the world of microbiology awestruck. To date, about 18 virophages have been isolated from different environmental sources. With their unique feature of resisting host cell infection and lysis by giant viruses, analogous to bacteriophage, they have been assigned under the family Lavidaviridae. Genome of T-27, icosahedral-shaped, non-enveloped virophages, consist of dsDNA encoding four proteins, namely, major capsid protein, minor capsid protein, ATPase and cysteine protease, which are essential in the formation and assembly of new virophage particles during replication. A few virophage genomes have been observed to contain additional sequences like PolB, ZnR and S3H. Another interesting characteristic of virophage is that Mimivirus lineage A is immune to infection by the Zamilon virophage through a phenomenon termed MIMIVIRE, resembling the CRISPR-Cas mechanism in bacteria. Based on the fact that giant viruses have been found in clinical samples of hospital-acquired pneumonia and rheumatoid arthritis patients, virophages have opened a novel era in the search for cures of various diseases. This article aims to study the prospective role of virophages in the future of human therapeutics.
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Affiliation(s)
- Debrupa Dutta
- National Institute of Pharmaceuticals Education and Research, 168, Maniktala Main Road, Kolkata, PIN-700054, West Bengal, India
| | - Velayutham Ravichandiran
- National Institute of Pharmaceuticals Education and Research, 168, Maniktala Main Road, Kolkata, PIN-700054, West Bengal, India
| | - Soumi Sukla
- National Institute of Pharmaceuticals Education and Research, 168, Maniktala Main Road, Kolkata, PIN-700054, West Bengal, India
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Zhou H, Chen P, Zhang M, Chen J, Fang J, Li X. Revealing the Viral Community in the Hadal Sediment of the New Britain Trench. Genes (Basel) 2021; 12:genes12070990. [PMID: 34209474 PMCID: PMC8306916 DOI: 10.3390/genes12070990] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 06/07/2021] [Accepted: 06/09/2021] [Indexed: 12/24/2022] Open
Abstract
Marine viruses are widely distributed and influence matter and energy transformation in ecosystems by modulating hosts’ metabolism. The hadal trenches represent the deepest marine habitat on Earth, for which the viral communities and related biogeochemical functions are least explored and poorly understood. Here, using the sediment samples (8720 m below sea level) collected from the New Britain Trench (NBT), we investigated the viral community, diversity, and genetic potentials in the hadal sediment habitat for the first time by deep shotgun metagenomic sequencing. We found the NBT sediment viral community was dominated by Siphoviridae, Myoviridae, Podoviridae, Mimiviridae, and Phycodnaviridae, which belong to the dsDNA viruses. However, the large majority of them remained uncharacterized. We found the hadal sediment virome had some common components by comparing the hadal sediment viruses with those of hadal aquatic habitats and those of bathypelagic and terrestrial habitats. It was also distinctive in community structure and had many novel viral clusters not associated with the other habitual virome included in our analyses. Further phylogenetic analysis on its Caudovirales showed novel diversities, including new clades specially evolved in the hadal sediment habitat. Annotation of the NBT sediment viruses indicated the viruses might influence microbial hydrocarbon biodegradation and carbon and sulfur cycling via metabolic augmentation through auxiliary metabolic genes (AMGs). Our study filled in the knowledge gaps on the virome of the hadal sediment habitats and provided insight into the evolution and the potential metabolic functions of the hadal sediment virome.
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Affiliation(s)
- Hui Zhou
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China; (H.Z.); (P.C.); (M.Z.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ping Chen
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China; (H.Z.); (P.C.); (M.Z.)
| | - Mengjie Zhang
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China; (H.Z.); (P.C.); (M.Z.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiawang Chen
- Ocean College, Zhejiang University, Zhoushan 316021, China
- Correspondence: (J.C.); (J.F.); (X.L.)
| | - Jiasong Fang
- Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China
- Correspondence: (J.C.); (J.F.); (X.L.)
| | - Xuan Li
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China; (H.Z.); (P.C.); (M.Z.)
- University of Chinese Academy of Sciences, Beijing 100049, China
- Correspondence: (J.C.); (J.F.); (X.L.)
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Abstract
Wastewater is a rich source of microbial life and contains bacteria, viruses, and other microbes found in human waste as well as environmental runoff sources. As part of an effort to characterize the New York City wastewater metagenome, we profiled the viral community of sewage samples across all five boroughs of NYC and found that local sampling sites have unique sets of viruses. We focused on bacteriophages, or viruses of bacteria, to understand how they may influence the microbial ecology of this system. We identified several new clusters of phages and successfully associated them with bacterial hosts, providing insight into virus-host interactions in urban wastewater. This study provides a first look into the viral communities present across the wastewater system in NYC and points to their functional importance in this environment. Bacteriophages are abundant members of all microbiomes studied to date, influencing microbial communities through interactions with their bacterial hosts. Despite their functional importance and ubiquity, phages have been underexplored in urban environments compared to their bacterial counterparts. We profiled the viral communities in New York City (NYC) wastewater using metagenomic data collected in November 2014 from 14 wastewater treatment plants. We show that phages accounted for the largest viral component of the sewage samples and that specific virus communities were associated with local environmental conditions within boroughs. The vast majority of the virus sequences had no homology matches in public databases, forming an average of 1,700 unique virus clusters (putative genera). These new clusters contribute to elucidating the overwhelming proportion of data that frequently goes unidentified in viral metagenomic studies. We assigned potential hosts to these phages, which appear to infect a wide range of bacterial genera, often outside their presumed host. We determined that infection networks form a modular-nested pattern, indicating that phages include a range of host specificities, from generalists to specialists, with most interactions organized into distinct groups. We identified genes in viral contigs involved in carbon and sulfur cycling, suggesting functional importance of viruses in circulating pathways and gene functions in the wastewater environment. In addition, we identified virophage genes as well as a nearly complete novel virophage genome. These findings provide an understanding of phage abundance and diversity in NYC wastewater, previously uncharacterized, and further examine geographic patterns of phage-host association in urban environments. IMPORTANCE Wastewater is a rich source of microbial life and contains bacteria, viruses, and other microbes found in human waste as well as environmental runoff sources. As part of an effort to characterize the New York City wastewater metagenome, we profiled the viral community of sewage samples across all five boroughs of NYC and found that local sampling sites have unique sets of viruses. We focused on bacteriophages, or viruses of bacteria, to understand how they may influence the microbial ecology of this system. We identified several new clusters of phages and successfully associated them with bacterial hosts, providing insight into virus-host interactions in urban wastewater. This study provides a first look into the viral communities present across the wastewater system in NYC and points to their functional importance in this environment.
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13
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Paez-Espino D, Roux S, Chen IMA, Palaniappan K, Ratner A, Chu K, Huntemann M, Reddy TBK, Pons JC, Llabrés M, Eloe-Fadrosh EA, Ivanova NN, Kyrpides NC. IMG/VR v.2.0: an integrated data management and analysis system for cultivated and environmental viral genomes. Nucleic Acids Res 2020; 47:D678-D686. [PMID: 30407573 PMCID: PMC6323928 DOI: 10.1093/nar/gky1127] [Citation(s) in RCA: 114] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Accepted: 10/31/2018] [Indexed: 01/06/2023] Open
Abstract
The Integrated Microbial Genome/Virus (IMG/VR) system v.2.0 (https://img.jgi.doe.gov/vr/) is the largest publicly available data management and analysis platform dedicated to viral genomics. Since the last report published in the 2016, NAR Database Issue, the data has tripled in size and currently contains genomes of 8389 cultivated reference viruses, 12 498 previously published curated prophages derived from cultivated microbial isolates, and 735 112 viral genomic fragments computationally predicted from assembled shotgun metagenomes. Nearly 60% of the viral genomes and genome fragments are clustered into 110 384 viral Operational Taxonomic Units (vOTUs) with two or more members. To improve data quality and predictions of host specificity, IMG/VR v.2.0 now separates prokaryotic and eukaryotic viruses, utilizes known prophage sequences to improve taxonomic assignments, and provides viral genome quality scores based on the estimated genome completeness. New features also include enhanced BLAST search capabilities for external queries. Finally, geographic map visualization to locate user-selected viral genomes or genome fragments has been implemented and download options have been extended. All of these features make IMG/VR v.2.0 a key resource for the study of viruses.
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Affiliation(s)
| | - Simon Roux
- Department of Energy, Joint Genome Institute, Walnut Creek, CA, USA
| | - I-Min A Chen
- Biological Data Management and Technology Center, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, USA
| | - Krishna Palaniappan
- Biological Data Management and Technology Center, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, USA
| | - Anna Ratner
- Biological Data Management and Technology Center, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, USA
| | - Ken Chu
- Biological Data Management and Technology Center, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, USA
| | - Marcel Huntemann
- Department of Energy, Joint Genome Institute, Walnut Creek, CA, USA
| | - T B K Reddy
- Department of Energy, Joint Genome Institute, Walnut Creek, CA, USA
| | - Joan Carles Pons
- Department of Mathematics and Computer Science, University of the Balearic Islands, Spain
| | - Mercè Llabrés
- Department of Mathematics and Computer Science, University of the Balearic Islands, Spain
| | | | | | - Nikos C Kyrpides
- Department of Energy, Joint Genome Institute, Walnut Creek, CA, USA
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14
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Masangkay FR, Milanez GD, Tsiami A, Hapan FZ, Somsak V, Kotepui M, Tangpong J, Karanis P. Waterborne protozoan pathogens in environmental aquatic biofilms: Implications for water quality assessment strategies. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 259:113903. [PMID: 32023789 DOI: 10.1016/j.envpol.2019.113903] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 12/29/2019] [Accepted: 12/29/2019] [Indexed: 06/10/2023]
Abstract
Biofilms containing pathogenic organisms from the water supply are a potential source of protozoan parasite outbreaks and a significant public health concern. The aim of the present study was to demonstrate the simultaneous and multi-spatial occurrence of waterborne protozoan pathogens (WBPP) in substrate-associated biofilms (SAB) and compare it to surface water (SW) and sediments with bottom water (BW) counterparts using manual filtration and elution from low-volume samples. For scenario purposes, simulated environmental biofilm contamination was created from in-situ grown one-month-old SAB (OM-SAB) that were spiked with Cryptosporidium parvum oocysts. Samples were collected from the largest freshwater reservoirs in Luzon, Philippines and a University Lake in Thailand. A total of 69 samples (23 SAB, 23 SW, and 23 BW) were evaluated using traditional staining techniques for Cryptosporidium, and Immunofluorescence staining for the simultaneous detection of Cryptosporidium and Giardia. WBPP were found in 43% SAB, 39% SW, and 39% BW of the samples tested in the present study with SAB results reflecting SW and BW results. Further highlights were demonstrated in the potential of using low-volume samples for the detection of parasites in source water. Scanning electron microscopy of OM-SAB samples revealed a naturally-associated testate amoeba shell, while Cryptosporidium oocysts spiked samples provided a visual profile of what can be expected from naturally contaminated biofilms. This study provides the first evidence for the simultaneous and multi-spatial occurrence of waterborne protozoan pathogens in low-volume aquatic matrices and further warrants SAB testing along with SW and BW matrices for improved water quality assessment strategies (iWQAS).
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Affiliation(s)
- Frederick R Masangkay
- Biomedical Sciences Program, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat, 80160, Thailand; Department of Medical Technology, Institute of Arts and Sciences, Far Eastern University Manila, 1015, Philippines.
| | - Giovanni D Milanez
- Biomedical Sciences Program, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat, 80160, Thailand; Department of Medical Technology, Institute of Arts and Sciences, Far Eastern University Manila, 1015, Philippines.
| | - Amalia Tsiami
- London Geller College of Hospitality and Tourism, University of West London, St Mary's Road, Ealing, London, W5 5RF, United Kingdom.
| | - Freida Z Hapan
- Department of Medical Technology, College of Pharmacy, The Pontifical and Royal University of Santo Tomas, España Blvd, Sampaloc, Manila, 1008, Philippines.
| | - Voravuth Somsak
- Biomedical Sciences Program, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat, 80160, Thailand.
| | - Manas Kotepui
- Biomedical Sciences Program, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat, 80160, Thailand.
| | - Jitbanjong Tangpong
- Biomedical Sciences Program, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat, 80160, Thailand.
| | - Panagiotis Karanis
- Medical Faculty and University Hospital of Cologne, Cologne, 50923, Germany; University of Nicosia Medical School, Nicosia, 2408, Cyprus.
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15
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Abstract
Colorectal cancer (CRC) is a leading cause of cancer-related deaths in both the USA and the world. Recent research has demonstrated the involvement of the gut microbiota in CRC development and progression. Microbial biomarkers of disease have focused primarily on the bacterial component of the microbiome; however, the viral portion of the microbiome, consisting of both bacteriophages and eukaryotic viruses, together known as the virome, has been lesser studied. Here we review the recent advancements in high-throughput sequencing (HTS) technologies and bioinformatics, which have enabled scientists to better understand how viruses might influence the development of colorectal cancer. We discuss the contemporary findings revealing modulations in the virome and their correlation with CRC development and progression. While a variety of challenges still face viral HTS detection in clinical specimens, we consider herein numerous next steps for future basic and clinical research. Clinicians need to move away from a single infectious agent model for disease etiology by grasping new, more encompassing etiological paradigms, in which communities of various microbial components interact with each other and the host. The reporting and indexing of patient health information, socioeconomic data, and other relevant metadata will enable identification of predictive variables and covariates of viral presence and CRC development. Altogether, the virome has a more profound role in carcinogenesis and cancer progression than once thought, and viruses, specific for either human cells or bacteria, are clinically relevant in understanding CRC pathology, patient prognosis, and treatment development.
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16
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Paez-Espino D, Zhou J, Roux S, Nayfach S, Pavlopoulos GA, Schulz F, McMahon KD, Walsh D, Woyke T, Ivanova NN, Eloe-Fadrosh EA, Tringe SG, Kyrpides NC. Diversity, evolution, and classification of virophages uncovered through global metagenomics. MICROBIOME 2019; 7:157. [PMID: 31823797 PMCID: PMC6905037 DOI: 10.1186/s40168-019-0768-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 11/11/2019] [Indexed: 05/19/2023]
Abstract
BACKGROUND Virophages are small viruses with double-stranded DNA genomes that replicate along with giant viruses and co-infect eukaryotic cells. Due to the paucity of virophage reference genomes, a collective understanding of the global virophage diversity, distribution, and evolution is lacking. RESULTS Here we screened a public collection of over 14,000 metagenomes using the virophage-specific major capsid protein (MCP) as "bait." We identified 44,221 assembled virophage sequences, of which 328 represent high-quality (complete or near-complete) genomes from diverse habitats including the human gut, plant rhizosphere, and terrestrial subsurface. Comparative genomic analysis confirmed the presence of four core genes in a conserved block. We used these genes to establish a revised virophage classification including 27 clades with consistent genome length, gene content, and habitat distribution. Moreover, for eight high-quality virophage genomes, we computationally predicted putative eukaryotic virus hosts. CONCLUSION Overall, our approach has increased the number of known virophage genomes by 10-fold and revealed patterns of genome evolution and global virophage distribution. We anticipate that the expanded diversity presented here will provide the backbone for further virophage studies.
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Affiliation(s)
- David Paez-Espino
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
| | - Jinglie Zhou
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
| | - Simon Roux
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
| | - Stephen Nayfach
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
| | - Georgios A. Pavlopoulos
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
- BSRC “Alexander Fleming”, 34 Fleming Street, Vari, 16672 Athens, Greece
| | - Frederik Schulz
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
| | - Katherine D. McMahon
- Departments of Civil and Environmental Engineering and Bacteriology, University of Wisconsin Madison, 1550 Linden Drive, Madison, WI 53726 USA
| | - David Walsh
- Department of Biology, Concordia University, 7141 Sherbrooke St. West, Montreal, QC, H4B 1R6 Canada
| | - Tanja Woyke
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
| | - Natalia N. Ivanova
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
| | - Emiley A. Eloe-Fadrosh
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
| | - Susannah G. Tringe
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
| | - Nikos C. Kyrpides
- Department of Energy, Joint Genome Institute, 2800 Mitchell Dr., Walnut Creek, 94598 USA
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17
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Exploration of the propagation of transpovirons within Mimiviridae reveals a unique example of commensalism in the viral world. ISME JOURNAL 2019; 14:727-739. [PMID: 31822788 PMCID: PMC7031253 DOI: 10.1038/s41396-019-0565-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 11/27/2019] [Accepted: 11/28/2019] [Indexed: 01/27/2023]
Abstract
Acanthamoeba-infecting Mimiviridae are giant viruses with dsDNA genome up to 1.5 Mb. They build viral factories in the host cytoplasm in which the nuclear-like virus-encoded functions take place. They are themselves the target of infections by 20-kb-dsDNA virophages, replicating in the giant virus factories and can also be found associated with 7-kb-DNA episomes, dubbed transpovirons. Here we isolated a virophage (Zamilon vitis) and two transpovirons respectively associated to B- and C-clade mimiviruses. We found that the virophage could transfer each transpoviron provided the host viruses were devoid of a resident transpoviron (permissive effect). If not, only the resident transpoviron originally isolated from the corresponding virus was replicated and propagated within the virophage progeny (dominance effect). Although B- and C-clade viruses devoid of transpoviron could replicate each transpoviron, they did it with a lower efficiency across clades, suggesting an ongoing process of adaptive co-evolution. We analysed the proteomes of host viruses and virophage particles in search of proteins involved in this adaptation process. This study also highlights a unique example of intricate commensalism in the viral world, where the transpoviron uses the virophage to propagate and where the Zamilon virophage and the transpoviron depend on the giant virus to replicate, without affecting its infectious cycle.
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18
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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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19
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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:E733. [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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20
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Protozoal giant viruses: agents potentially infectious to humans and animals. Virus Genes 2019; 55:574-591. [PMID: 31290063 PMCID: PMC6746690 DOI: 10.1007/s11262-019-01684-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 07/02/2019] [Indexed: 12/11/2022]
Abstract
The discovery of giant viruses has revolutionised the knowledge on viruses and transformed the idea of three domains of life. Here, we discuss the known protozoal giant viruses and their potential to infect also humans and animals.
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21
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Defective viral genomes are key drivers of the virus-host interaction. Nat Microbiol 2019; 4:1075-1087. [PMID: 31160826 PMCID: PMC7097797 DOI: 10.1038/s41564-019-0465-y] [Citation(s) in RCA: 192] [Impact Index Per Article: 38.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 04/23/2019] [Indexed: 12/12/2022]
Abstract
Viruses survive often harsh host environments, yet we know little about the strategies they utilize to adapt and subsist given their limited genomic resources. We are beginning to appreciate the surprising versatility of viral genomes and how replication-competent and -defective virus variants can provide means for adaptation, immune escape and virus perpetuation. This Review summarizes current knowledge of the types of defective viral genomes generated during the replication of RNA viruses and the functions that they carry out. We highlight the universality and diversity of defective viral genomes during infections and discuss their predicted role in maintaining a fit virus population, their impact on human and animal health, and their potential to be harnessed as antiviral tools. This Review describes recent findings on the biogenesis and the role of defective viral genomes during replication of RNA viruses and discusses their impact on viral dynamics and evolution.
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22
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Mougari S, Bekliz M, Abrahao J, Di Pinto F, Levasseur A, La Scola B. Guarani Virophage, a New Sputnik-Like Isolate From a Brazilian Lake. Front Microbiol 2019; 10:1003. [PMID: 31130943 PMCID: PMC6510173 DOI: 10.3389/fmicb.2019.01003] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 04/18/2019] [Indexed: 01/23/2023] Open
Abstract
Virophages are critical regulators of viral population dynamics and potential actors in the stability of the microbial networks. These small biological entities predate the replicative cycle of giant viruses, such as the members of the Mimiviridae family or their distant relatives, which produce within the cytoplasm of their host cells a viral factory harboring a complex biochemistry propitious to the growth of the smaller parasites. In this paper, we describe the isolation and the characterization of a new virophage, the eighth, that we named Guarani. We observed that Guarani exhibits a late replication cycle compared to its giant virus host. In addition, like all Sputnik strains, Guarani is able to infect the three lineages A, B and C of the Mimiviridae family, and affects the replication and the infectivity of its host virus. In terms of genetic content, Guarani has a 18,967 bp long double-stranded DNA genome encoding 22 predicted genes very similar to Sputnik genes, except for ORF19 and ORF12. The former is more related to Zamilon while the latter seems to be novel. The architecture of the Guarani genome is closely related to Sputnik and Zamilon strains, suggesting a common origin for all these virophages.
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Affiliation(s)
- Said Mougari
- MEPHI, APHM, IRD 198, Department of Medicine, IHU-Méditerranée Infection, Aix-Marseille University, Marseille, France
| | - Meriem Bekliz
- MEPHI, APHM, IRD 198, Department of Medicine, IHU-Méditerranée Infection, Aix-Marseille University, Marseille, France
| | - Jonatas Abrahao
- MEPHI, APHM, IRD 198, Department of Medicine, IHU-Méditerranée Infection, Aix-Marseille University, Marseille, France.,Laboratório de Vírus, Instituto de Ciências Biológicas, Departamento de Microbiologia, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Fabrizio Di Pinto
- MEPHI, APHM, IRD 198, Department of Medicine, IHU-Méditerranée Infection, Aix-Marseille University, Marseille, France
| | - Anthony Levasseur
- MEPHI, APHM, IRD 198, Department of Medicine, IHU-Méditerranée Infection, Aix-Marseille University, Marseille, France
| | - Bernard La Scola
- MEPHI, APHM, IRD 198, Department of Medicine, IHU-Méditerranée Infection, Aix-Marseille University, Marseille, France
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23
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Brandes N, Linial M. Giant Viruses-Big Surprises. Viruses 2019; 11:v11050404. [PMID: 31052218 PMCID: PMC6563228 DOI: 10.3390/v11050404] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 04/17/2019] [Accepted: 04/23/2019] [Indexed: 12/21/2022] Open
Abstract
Viruses are the most prevalent infectious agents, populating almost every ecosystem on earth. Most viruses carry only a handful of genes supporting their replication and the production of capsids. It came as a great surprise in 2003 when the first giant virus was discovered and found to have a >1 Mbp genome encoding almost a thousand proteins. Following this first discovery, dozens of giant virus strains across several viral families have been reported. Here, we provide an updated quantitative and qualitative view on giant viruses and elaborate on their shared and variable features. We review the complexity of giant viral proteomes, which include functions traditionally associated only with cellular organisms. These unprecedented functions include components of the translation machinery, DNA maintenance, and metabolic enzymes. We discuss the possible underlying evolutionary processes and mechanisms that might have shaped the diversity of giant viruses and their genomes, highlighting their remarkable capacity to hijack genes and genomic sequences from their hosts and environments. This leads us to examine prominent theories regarding the origin of giant viruses. Finally, we present the emerging ecological view of giant viruses, found across widespread habitats and ecological systems, with respect to the environment and human health.
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Affiliation(s)
- Nadav Brandes
- The Rachel and Selim Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
| | - Michal Linial
- Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
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24
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Duponchel S, Fischer MG. Viva lavidaviruses! Five features of virophages that parasitize giant DNA viruses. PLoS Pathog 2019; 15:e1007592. [PMID: 30897185 PMCID: PMC6428243 DOI: 10.1371/journal.ppat.1007592] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Affiliation(s)
- Sarah Duponchel
- Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Matthias G. Fischer
- Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, Heidelberg, Germany
- * E-mail:
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25
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Mimiviridae: An Expanding Family of Highly Diverse Large dsDNA Viruses Infecting a Wide Phylogenetic Range of Aquatic Eukaryotes. Viruses 2018; 10:v10090506. [PMID: 30231528 PMCID: PMC6163669 DOI: 10.3390/v10090506] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 09/13/2018] [Accepted: 09/15/2018] [Indexed: 01/22/2023] Open
Abstract
Since 1998, when Jim van Etten’s team initiated its characterization, Paramecium bursaria Chlorella virus 1 (PBCV-1) had been the largest known DNA virus, both in terms of particle size and genome complexity. In 2003, the Acanthamoeba-infecting Mimivirus unexpectedly superseded PBCV-1, opening the era of giant viruses, i.e., with virions large enough to be visible by light microscopy and genomes encoding more proteins than many bacteria. During the following 15 years, the isolation of many Mimivirus relatives has made Mimiviridae one of the largest and most diverse families of eukaryotic viruses, most of which have been isolated from aquatic environments. Metagenomic studies of various ecosystems (including soils) suggest that many more remain to be isolated. As Mimiviridae members are found to infect an increasing range of phytoplankton species, their taxonomic position compared to the traditional Phycodnaviridae (i.e., etymologically “algal viruses”) became a source of confusion in the literature. Following a quick historical review of the key discoveries that established the Mimiviridae family, we describe its current taxonomic structure and propose a set of operational criteria to help in the classification of future isolates.
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26
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Koonin EV, Krupovic M. The depths of virus exaptation. Curr Opin Virol 2018; 31:1-8. [PMID: 30071360 DOI: 10.1016/j.coviro.2018.07.011] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 07/13/2018] [Accepted: 07/19/2018] [Indexed: 02/07/2023]
Abstract
Viruses are ubiquitous parasites of cellular life forms and the most abundant biological entities on earth. The relationships between viruses and their hosts involve the continuous arms race but are by no account limited to it. Growing evidence shows that, in the course of evolution, viruses and their components are repeatedly recruited (exapted) for host functions. The functions of exapted viruses typically involve either defense from other viruses or cellular competitors or transfer of nucleic acids between cells, or storage functions. Virus exaptation can reach different depths, from recruitment of a fully functional virus to exploitation of defective, partially degraded viruses, to utilization of individual virus proteins.
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Affiliation(s)
- Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, United States.
| | - Mart Krupovic
- Unité Biologie Moléculaire du Gène chez les Extrêmophiles, Department of Microbiology, Institut Pasteur, 25 rue du Docteur Roux, Paris 75015, France.
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27
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Howard-Varona C, Hargreaves KR, Solonenko NE, Markillie LM, White RA, Brewer HM, Ansong C, Orr G, Adkins JN, Sullivan MB. Multiple mechanisms drive phage infection efficiency in nearly identical hosts. THE ISME JOURNAL 2018; 12:1605-1618. [PMID: 29568113 PMCID: PMC5955906 DOI: 10.1038/s41396-018-0099-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 01/08/2018] [Accepted: 02/20/2018] [Indexed: 12/15/2022]
Abstract
Phage-host interactions are critical to ecology, evolution, and biotechnology. Central to those is infection efficiency, which remains poorly understood, particularly in nature. Here we apply genome-wide transcriptomics and proteomics to investigate infection efficiency in nature's own experiment: two nearly identical (genetically and physiologically) Bacteroidetes bacterial strains (host18 and host38) that are genetically intractable, but environmentally important, where phage infection efficiency varies. On host18, specialist phage phi18:3 infects efficiently, whereas generalist phi38:1 infects inefficiently. On host38, only phi38:1 infects, and efficiently. Overall, phi18:3 globally repressed host18's transcriptome and proteome, expressed genes that likely evaded host restriction/modification (R/M) defenses and controlled its metabolism, and synchronized phage transcription with translation. In contrast, phi38:1 failed to repress host18's transcriptome and proteome, did not evade host R/M defenses or express genes for metabolism control, did not synchronize transcripts with proteins and its protein abundances were likely targeted by host proteases. However, on host38, phi38:1 globally repressed host transcriptome and proteome, synchronized phage transcription with translation, and infected host38 efficiently. Together these findings reveal multiple infection inefficiencies. While this contrasts the single mechanisms often revealed in laboratory mutant studies, it likely better reflects the phage-host interaction dynamics that occur in nature.
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Affiliation(s)
| | | | | | - Lye Meng Markillie
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory (PNNL), Richland, WA, USA
| | | | - Heather M Brewer
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory (PNNL), Richland, WA, USA
| | | | - Galya Orr
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory (PNNL), Richland, WA, USA
| | | | - Matthew B Sullivan
- Department of Microbiology, The Ohio State University, Columbus, OH, USA.
- Department of Civil, Environmental and Geodetic Engineering, The Ohio State University, Columbus, OH, USA.
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28
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Sobhy H. Virophages and Their Interactions with Giant Viruses and Host Cells. Proteomes 2018; 6:proteomes6020023. [PMID: 29786634 PMCID: PMC6027436 DOI: 10.3390/proteomes6020023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 04/15/2018] [Accepted: 05/17/2018] [Indexed: 01/13/2023] Open
Abstract
Virophages are small dsDNA viruses that were first isolated in association with some giant viruses (GVs), and then found in metagenomics samples. They encode about 20–34 proteins. Some virophages share protein similarity with Maverick/Polinton transposons or are considered as a provirophage, whereas about half of the protein’s repertoire remain of unknown function. In this review, we aim to highlight the current understanding of the biology of virophages, as well as their interactions with giant viruses and host cells. Additionally, the virophage proteomes were analyzed to find the functional domains that distinguish each virophage. This bioinformatics analysis will benefit further experimental investigations to understand the protein-protein interactions between virophages, giant viruses, and host cells.
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Affiliation(s)
- Haitham Sobhy
- Helmy Institute for Medical Sciences, Zewail City of Science and Technology, Ahmed Zewail Road, October Gardens, 6th of October City, Giza 12566, Egypt.
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29
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Gupta A, Patil S, Vijayakumar R, Kondabagil K. The Polyphyletic Origins of Primase-Helicase Bifunctional Proteins. J Mol Evol 2017; 85:188-204. [PMID: 29143083 DOI: 10.1007/s00239-017-9816-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 10/28/2017] [Indexed: 11/28/2022]
Abstract
We studied the evolutionary relationships of different primase-helicase bifunctional proteins, found mostly in viruses, virophages, plasmids, and organellar genomes, by phylogeny and correlation analysis. Our study suggests independent origins of primase-helicase bifunctional proteins resulting from multiple fusion events between genes encoding primase and helicase domains of different families. The correlation analysis further indicated strong functional dependencies of domains in the bifunctional proteins that are part of smaller genomes and plasmids. Bifunctional proteins found in some bacterial genomes exhibited weak coevolution probably suggesting that these are the non-functional remnants of the proteins acquired via horizontal transfer. We have put forward possible scenarios for the origin of primase-helicase bifunctional proteins in large eukaryotic DNA viruses and virophages.
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Affiliation(s)
- Ankita Gupta
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Supriya Patil
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Ramya Vijayakumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Kiran Kondabagil
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India.
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30
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López-Pérez M, Haro-Moreno JM, Gonzalez-Serrano R, Parras-Moltó M, Rodriguez-Valera F. Genome diversity of marine phages recovered from Mediterranean metagenomes: Size matters. PLoS Genet 2017; 13:e1007018. [PMID: 28945750 PMCID: PMC5628999 DOI: 10.1371/journal.pgen.1007018] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 10/05/2017] [Accepted: 09/13/2017] [Indexed: 11/18/2022] Open
Abstract
Marine viruses play a critical role not only in the global geochemical cycles but also in the biology and evolution of their hosts. Despite their importance, viral diversity remains underexplored mostly due to sampling and cultivation challenges. Direct sequencing approaches such as viromics has provided new insights into the marine viral world. As a complementary approach, we analysed 24 microbial metagenomes (>0.2 μm size range) obtained from six sites in the Mediterranean Sea that vary by depth, season and filter used to retrieve the fraction. Filter-size comparison showed a significant number of viral sequences that were retained on the larger-pore filters and were different from those found in the viral fraction from the same sample, indicating that some important viral information is missing using only assembly from viromes. Besides, we were able to describe 1,323 viral genomic fragments that were more than 10Kb in length, of which 36 represented complete viral genomes including some of them retrieved from a cross-assembly from different metagenomes. Host prediction based on sequence methods revealed new phage groups belonging to marine prokaryotes like SAR11, Cyanobacteria or SAR116. We also identified the first complete virophage from deep seawater and a new endemic clade of the recently discovered Marine group II Euryarchaeota virus. Furthermore, analysis of viral distribution using metagenomes and viromes indicated that most of the new phages were found exclusively in the Mediterranean Sea and some of them, mostly the ones recovered from deep metagenomes, do not recruit in any database probably indicating higher variability and endemicity in Mediterranean bathypelagic waters. Together these data provide the first detailed picture of genomic diversity, spatial and depth variations of viral communities within the Mediterranean Sea using metagenome assembly.
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Affiliation(s)
- Mario López-Pérez
- Evolutionary Genomics Group, División de Microbiología, Universidad Miguel Hernández, Campus de San Juan, San Juan de Alicante, Spain
| | - Jose M. Haro-Moreno
- Evolutionary Genomics Group, División de Microbiología, Universidad Miguel Hernández, Campus de San Juan, San Juan de Alicante, Spain
| | - Rafael Gonzalez-Serrano
- Evolutionary Genomics Group, División de Microbiología, Universidad Miguel Hernández, Campus de San Juan, San Juan de Alicante, Spain
| | - Marcos Parras-Moltó
- Centro de Biología Molecular 'Severo Ochoa' (Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid), Cantoblanco, Madrid, Spain
| | - Francisco Rodriguez-Valera
- Evolutionary Genomics Group, División de Microbiología, Universidad Miguel Hernández, Campus de San Juan, San Juan de Alicante, Spain
- * E-mail:
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31
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Colson P, La Scola B, Raoult D. Giant Viruses of Amoebae: A Journey Through Innovative Research and Paradigm Changes. Annu Rev Virol 2017; 4:61-85. [PMID: 28759330 DOI: 10.1146/annurev-virology-101416-041816] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Giant viruses of amoebae were discovered serendipitously in 2003; they are visible via optical microscopy, making them bona fide microbes. Their lifestyle, structure, and genomes break the mold of classical viruses. Giant viruses of amoebae are complex microorganisms. Their genomes harbor between 444 and 2,544 genes, including many that are unique to viruses, and encode translation components; their virions contain >100 proteins as well as mRNAs. Mimiviruses have a specific mobilome, including virophages, provirophages, and transpovirons, and can resist virophages through a system known as MIMIVIRE (mimivirus virophage resistance element). Giant viruses of amoebae bring upheaval to the definition of viruses and tend to separate the current virosphere into two categories: very simple viruses and viruses with complexity similar to that of other microbes. This new paradigm is propitious for enhanced detection and characterization of giant viruses of amoebae, and a particular focus on their role in humans is warranted.
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Affiliation(s)
- Philippe Colson
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes (URMITE), Aix Marseille Université, UM63, CNRS 7278, IRD 198, INSERM 1095, Institut Hospitalo-Universitaire (IHU) Méditerranée Infection, Assistance Publique-Hôpitaux de Marseille (AP-HM), 13005 Marseille, France;
| | - Bernard La Scola
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes (URMITE), Aix Marseille Université, UM63, CNRS 7278, IRD 198, INSERM 1095, Institut Hospitalo-Universitaire (IHU) Méditerranée Infection, Assistance Publique-Hôpitaux de Marseille (AP-HM), 13005 Marseille, France;
| | - Didier Raoult
- Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes (URMITE), Aix Marseille Université, UM63, CNRS 7278, IRD 198, INSERM 1095, Institut Hospitalo-Universitaire (IHU) Méditerranée Infection, Assistance Publique-Hôpitaux de Marseille (AP-HM), 13005 Marseille, France;
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32
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Koonin EV, Krupovic M. Polintons, virophages and transpovirons: a tangled web linking viruses, transposons and immunity. Curr Opin Virol 2017; 25:7-15. [PMID: 28672161 DOI: 10.1016/j.coviro.2017.06.008] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 05/30/2017] [Accepted: 06/19/2017] [Indexed: 11/15/2022]
Abstract
Virophages are satellite DNA viruses that depend for their replication on giant viruses of the family Mimiviridae. An evolutionary relationship exists between the virophages and Polintons, large self-synthesizing transposons that are wide spread in the genomes of diverse eukaryotes. Most of the Polintons encode homologs of major and minor icosahedral virus capsid proteins and accordingly are predicted to form virions. Additionally, metagenome analysis has led to the discovery of an expansive family of Polinton-like viruses (PLV) that are more distantly related to bona fide Polintons and virophages. Another group of giant virus parasites includes small, linear, double-stranded DNA elements called transpovirons. Recent in-depth comparative genomic analysis has yielded evidence of the origin of the PLV and the transpovirons from Polintons. Integration of virophage genomes into genomes of both giant viruses and protists has been demonstrated. Furthermore, in an experimental coinfection system that consisted of a protist host, a giant virus and an associated virophage, the virophage integrated into the host genome and, after activation of its expression by a superinfecting giant virus, served as an agent of adaptive immunity. There is a striking analogy between this mechanism and the CRISPR-Cas system of prokaryotic adaptive immunity. Taken together, these findings show that Polintons, PLV, virophages and transpovirons form a dynamic network of integrating mobile genetic elements that contribute to the cellular antivirus defense and host-virus coevolution.
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Affiliation(s)
- Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA.
| | - Mart Krupovic
- Unité Biologie Moléculaire du Gène chez les Extrêmophiles, Department of Microbiology, Institut Pasteur, Paris, France.
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