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de Aquino ILM, Barcelos MG, Machado TB, Serafim MSM, Abrahão JS. Surface fibrils on the particles of nucleocytoviruses: A review. Exp Biol Med (Maywood) 2023; 248:2045-2052. [PMID: 37955170 PMCID: PMC10800130 DOI: 10.1177/15353702231208410] [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: 11/14/2023] Open
Abstract
The capsid has a central role in viruses' life cycle. Although one of its major functions is to protect the viral genome, the capsid may be composed of elements that, at some point, promote interaction with host cells and trigger infection. Considering the scenario of multiple origins of viruses along the viral evolution, a substantial number of capsid shapes, sizes, and symmetries have been described. In this context, capsids of giant viruses (GV) that infect protists have drawn the attention of the scientific community, especially in the last 20 years, specifically for having bacterial-like dimensions with hundreds of different proteins and exclusive features. For instance, the surface fibrils present on the mimivirus capsid are one of the most intriguing features of the known virosphere. They are 150-nm-long structures attached to a 450-nm capsid, resulting in a particle with a hairy appearance. Surface fibrils have also been described in the capsids of other nucleocytoviruses, although they may differ substantially among them. In this mini review for non-experts, we compile the most important available information on surface fibrils of nucleocytoviruses, discussing their putative functions, composition, length, organization, and origins.
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Affiliation(s)
- Isabella Luiza Martins de Aquino
- Laboratório de Vírus, Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte 31270-901, Brazil
| | - Matheus Gomes Barcelos
- Laboratório de Vírus, Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte 31270-901, Brazil
| | - Talita Bastos Machado
- Laboratório de Vírus, Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte 31270-901, Brazil
| | - Mateus Sá Magalhães Serafim
- Laboratório de Vírus, Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte 31270-901, Brazil
| | - Jônatas Santos Abrahão
- Laboratório de Vírus, Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte 31270-901, Brazil
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Ji Y, Xi H, Zhao Z, Jiang Q, Chen C, Wang X, Li F, Li N, Sun C, Feng X, Lei L, Han W, Gu J. Metagenomics analysis reveals potential pathways and drivers of piglet gut phage-mediated transfer of ARGs. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 859:160304. [PMID: 36427721 DOI: 10.1016/j.scitotenv.2022.160304] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 11/13/2022] [Accepted: 11/15/2022] [Indexed: 06/16/2023]
Abstract
The growing prevalence of antibiotic-resistant pathogens has led to a better understanding of the underlying processes that lead to this expansion. Intensive pig farms are considered one of the hotspots for antibiotic resistance gene (ARG) transmission. Phages, as important mobile carriers of ARGs, are widespread in the animal intestine. However, our understanding of phage-associated ARGs in the pig intestine and their underlying drivers is limited. Here, metagenomic sequencing and analysis of viral DNA and total DNA of different intestinal (ileum, cecum and feces) contents in healthy piglets and piglets with diarrhea were separately conducted. We found that phages in piglet ceca are the main repository for ARGs and mobile genetic element (MGE) genes. Phage-associated MGEs are important factors affecting the maintenance and transfer of ARGs. Interestingly, the colocalization of ARGs and MGE genes in piglet gut phages does not appear to be randomly selected but rather related to a specific phage host (Streptococcus). In addition, in the feces of piglets with diarrhea, the abundance of phages carrying ARGs and MGE genes was significantly increased, as was the diversity of polyvalent phages (phages with broad host ranges), which would facilitate the transfection and wider distribution of ARGs in the bacterial community. Moreover, the predicted host spectrum of polyvalent phages in diarrheal feces tended to be potential enteropathogenic genera, which greatly increased the risk of enteropathogens acquiring ARGs. Notably, we also found ARG-homologous genes in the sequences of piglet intestinal mimiviruses, suggesting that the piglet intestinal mimiviruses are a potential repository of ARGs. In conclusion, this study greatly expands our knowledge of the piglet gut microbiome, revealing the underlying mechanisms of maintenance and dissemination of piglet gut ARGs and providing a reference for the prevention and control of ARG pollution in animal husbandry.
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Affiliation(s)
- Yalu Ji
- State Key Laboratory for Zoonotic Diseases, Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun 130062, People's Republic of China
| | - Hengyu Xi
- State Key Laboratory for Zoonotic Diseases, Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun 130062, People's Republic of China
| | - Zhen Zhao
- State Key Laboratory for Zoonotic Diseases, Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun 130062, People's Republic of China
| | - Qiujie Jiang
- Jilin Animal Disease Control Center, Changchun 130062, People's Republic of China
| | - Chong Chen
- State Key Laboratory for Zoonotic Diseases, Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun 130062, People's Republic of China
| | - Xinwu Wang
- State Key Laboratory for Zoonotic Diseases, Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun 130062, People's Republic of China
| | - Fengyang Li
- State Key Laboratory for Zoonotic Diseases, Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun 130062, People's Republic of China
| | - Na Li
- State Key Laboratory for Zoonotic Diseases, Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun 130062, People's Republic of China
| | - Changjiang Sun
- State Key Laboratory for Zoonotic Diseases, Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun 130062, People's Republic of China
| | - Xin Feng
- State Key Laboratory for Zoonotic Diseases, Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun 130062, People's Republic of China
| | - Liancheng Lei
- State Key Laboratory for Zoonotic Diseases, Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun 130062, People's Republic of China
| | - Wenyu Han
- State Key Laboratory for Zoonotic Diseases, Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun 130062, People's Republic of China; Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, People's Republic of China.
| | - Jingmin Gu
- State Key Laboratory for Zoonotic Diseases, Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun 130062, People's Republic of China; Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, People's Republic of China.
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3
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Wuerth JD, Weber F. Shielding the mRNA-translation factor eIF2B from inhibitory p-eIF2 as a viral strategy to evade protein kinase R-mediated innate immunity. Curr Opin Immunol 2022; 78:102251. [PMID: 36242870 DOI: 10.1016/j.coi.2022.102251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 09/05/2022] [Indexed: 01/29/2023]
Abstract
The interferon-regulated kinase PKR (protein kinase RNA-activated) is a potent innate immune factor against a broad range of viruses. Being part of the integrated stress response (ISR), its restrictive effect is predominantly exerted by phosphorylating the eukaryotic translation-initiation factor eIF2, thereby turning it into an inhibitor of translation-initiation factor eIF2B. A plethora of viruses are known to evade the shutdown of cellular mRNA translation by interfering either with PKR activation or with eIF2 phosphorylation. Recently, a novel PKR evasion strategy was described: proteins from three taxonomically distinct RNA viruses allow for full PKR activation and eIF2 phosphorylation in the infected cell, but protect eIF2B from inhibition by phosphorylated eIF2, thus enabling mRNA translation in the presence of an activated ISR.
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Affiliation(s)
- Jennifer D Wuerth
- Institute of Innate Immunity, Medical Faculty, University of Bonn, 53127 Bonn, Germany
| | - Friedemann Weber
- Institute for Virology, FB10-Veterinary Medicine, Justus-Liebig University, D-35392 Giessen, Germany.
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Hernández G. Schrödinger and the Possible Existence of Different Types of Life. Front Microbiol 2022; 13:902212. [PMID: 35711773 PMCID: PMC9194607 DOI: 10.3389/fmicb.2022.902212] [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] [Received: 03/22/2022] [Accepted: 05/11/2022] [Indexed: 11/13/2022] Open
Abstract
Eighty years ago, Nobel Prize-winner physicist Erwin Schrödinger gave three lectures in Dublin’s Trinity College, titled What is Life? The physical aspect of the living cell to explain life in terms of the chemistry and physics laws. Life definitions rely on the cellular theory, which poses in the first place that life is made up of cells. The recent discovery of giant viruses, along with the development of synthetic cells at the beginning of century 21st, has challenged the current idea of what life is. Thus, rather than having arrived at a close answer to Schrödinger’s question, modern biology has touched down at a novel scenario in which several types of life—as opposed to only one—actually might exist on Earth and possibly the Universe. Eighty years after the Dublin lectures, the Schrödinger question could be: “What are lives”?
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Affiliation(s)
- Greco Hernández
- Translation and Cancer Laboratory, Unit of Biomedical Research on Cancer, National Institute of Cancer (Instituto Nacional de Cancerología, INCan), Mexico City, Mexico
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Koonin EV, Dolja VV, Krupovic M, Kuhn JH. Viruses Defined by the Position of the Virosphere within the Replicator Space. Microbiol Mol Biol Rev 2021; 85:e0019320. [PMID: 34468181 PMCID: PMC8483706 DOI: 10.1128/mmbr.00193-20] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Originally, viruses were defined as miniscule infectious agents that passed through filters that retain even the smallest cells. Subsequently, viruses were considered obligate intracellular parasites whose reproduction depends on their cellular hosts for energy supply and molecular building blocks. However, these features are insufficient to unambiguously define viruses as they are broadly understood today. We outline possible approaches to define viruses and explore the boundaries of the virosphere within the virtual space of replicators and the relationships between viruses and other types of replicators. Regardless of how, exactly, viruses are defined, viruses clearly have evolved on many occasions from nonviral replicators, such as plasmids, by recruiting host proteins to become virion components. Conversely, other types of replicators have repeatedly evolved from viruses. Thus, the virosphere is a dynamic entity with extensive evolutionary traffic across its boundaries. We argue that the virosphere proper, here termed orthovirosphere, consists of a distinct variety of replicators that encode structural proteins encasing the replicators' genomes, thereby providing protection and facilitating transmission among hosts. Numerous and diverse replicators, such as virus-derived but capsidless RNA and DNA elements, or defective viruses occupy the zone surrounding the orthovirosphere in the virtual replicator space. We define this zone as the perivirosphere. Although intense debates on the nature of certain replicators that adorn the internal and external boundaries of the virosphere will likely continue, we present an operational definition of virus that recently has been accepted by the International Committee on Taxonomy of Viruses.
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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
| | - Valerian V. Dolja
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon, USA
| | - Mart Krupovic
- Archaeal Virology Unit, Institut Pasteur, Paris, France
| | - Jens H. Kuhn
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Frederick, Maryland, USA
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Bockhaus NJ, Ferek JD, Thoden JB, Holden HM. The high-resolution structure of a UDP-L-rhamnose synthase from Acanthamoeba polyphaga Mimivirus. Protein Sci 2020; 29:2164-2174. [PMID: 32797646 DOI: 10.1002/pro.3928] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 08/11/2020] [Accepted: 08/11/2020] [Indexed: 12/14/2022]
Abstract
For the field of virology, perhaps one of the most paradigm-shifting events so far in the 21st century was the identification of the giant double-stranded DNA virus that infects amoebae. Remarkably, this virus, known as Mimivirus, has a genome that encodes for nearly 1,000 proteins, some of which are involved in the biosynthesis of unusual sugars. Indeed, the virus is coated by a layer of glycosylated fibers that contain d-glucose, N-acetyl-d-glucosamine, l-rhamnose, and 4-amino-4,6-dideoxy-d-glucose. Here we describe a combined structural and enzymological investigation of the protein encoded by the open-reading frame L780, which corresponds to an l-rhamnose synthase. The structure of the L780/NADP+ /UDP-l-rhamnose ternary complex was determined to 1.45 Å resolution and refined to an overall R-factor of 19.9%. Each subunit of the dimeric protein adopts a bilobal-shaped appearance with the N-terminal domain harboring the dinucleotide-binding site and the C-terminal domain positioning the UDP-sugar into the active site. The overall molecular architecture of L780 places it into the short-chain dehydrogenase/reductase superfamily. Kinetic analyses indicate that the enzyme can function on either UDP- and dTDP-sugars but displays a higher catalytic efficiency with the UDP-linked substrate. Site-directed mutagenesis experiments suggest that both Cys 108 and Lys 175 play key roles in catalysis. This structure represents the first model of a viral UDP-l-rhamnose synthase and provides new details into these fascinating enzymes.
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Affiliation(s)
- Nicholas J Bockhaus
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin, USA
| | - Justin D Ferek
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin, USA
| | - James B Thoden
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin, USA
| | - Hazel M Holden
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin, USA
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Abstract
Here we report the discovery of Yaravirus, a lineage of amoebal virus with a puzzling origin and evolution. Yaravirus presents 80-nm-sized particles and a 44,924-bp dsDNA genome encoding for 74 predicted proteins. Yaravirus genome annotation showed that none of its genes matched with sequences of known organisms at the nucleotide level; at the amino acid level, six predicted proteins had distant matches in the nr database. Complimentary prediction of three-dimensional structures indicated possible function of 17 proteins in total. Furthermore, we were not able to retrieve viral genomes closely related to Yaravirus in 8,535 publicly available metagenomes spanning diverse habitats around the globe. The Yaravirus genome also contained six types of tRNAs that did not match commonly used codons. Proteomics revealed that Yaravirus particles contain 26 viral proteins, one of which potentially representing a divergent major capsid protein (MCP) with a predicted double jelly-roll domain. Structure-guided phylogeny of MCP suggests that Yaravirus groups together with the MCPs of Pleurochrysis endemic viruses. Yaravirus expands our knowledge of the diversity of DNA viruses. The phylogenetic distance between Yaravirus and all other viruses highlights our still preliminary assessment of the genomic diversity of eukaryotic viruses, reinforcing the need for the isolation of new viruses of protists.
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Ferek JD, Thoden JB, Holden HM. Biochemical analysis of a sugar 4,6-dehydratase from Acanthamoeba polyphaga Mimivirus. Protein Sci 2020; 29:1148-1159. [PMID: 32083779 DOI: 10.1002/pro.3843] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 02/17/2020] [Accepted: 02/17/2020] [Indexed: 02/06/2023]
Abstract
The exciting discovery of the giant DNA Mimivirus in 2003 challenged the conventional description of viruses in a radical way, and since then, dozens of additional giant viruses have been identified. It has now been demonstrated that the Mimivirus genome encodes for the two enzymes required for the production of the unusual sugar 4-amino-4,6-dideoxy-d-glucose, namely a 4,6-dehydratase and an aminotransferase. In light of our long-standing interest in the bacterial 4,6-dehydratases and in unusual sugars in general, we conducted a combined structural and functional analysis of the Mimivirus 4,6-dehydratase referred to as R141. For this investigation, the three-dimensional X-ray structure of R141 was determined to 2.05 Å resolution and refined to an R-factor of 18.3%. The overall fold of R141 places it into the short-chain dehydrogenase/reductase (SDR) superfamily of proteins. Whereas its molecular architecture is similar to that observed for the bacterial 4,6-dehydratases, there are two key regions where the polypeptide chain adopts different conformations. In particular, the conserved tyrosine that has been implicated as a catalytic acid or base in SDR superfamily members is splayed away from the active site by nearly 12 Å, thereby suggesting that a major conformational change must occur upon substrate binding. In addition to the structural analysis, the kinetic parameters for R141 using either dTDP-d-glucose or UDP-d-glucose as substrates were determined. Contrary to a previous report, R141 demonstrates nearly identical catalytic efficiency with either nucleotide-linked sugar. The data presented herein represent the first three-dimensional model for a viral 4,6-dehydratase and thus expands our understanding of these fascinating enzymes.
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Affiliation(s)
- Justin D Ferek
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin, United States
| | - James B Thoden
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin, United States
| | - Hazel M Holden
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin, United States
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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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Mougari S, Abrahao J, Oliveira GP, Bou Khalil JY, La Scola B. Role of the R349 Gene and Its Repeats in the MIMIVIRE Defense System. Front Microbiol 2019; 10:1147. [PMID: 31178847 PMCID: PMC6538805 DOI: 10.3389/fmicb.2019.01147] [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: 01/22/2019] [Accepted: 05/06/2019] [Indexed: 01/16/2023] Open
Abstract
MIMIVIRE is a defense system described in lineage A Mimivirus (Mimiviridae family) that mediates resistance against Zamilon virophage. It is composed of putative helicase and nuclease associated with a gene of unknown function called R349, which contains four 15 bp repeats homologous to the virophage sequence. In a previous study, the silencing of such genes restored virophage susceptibility. Moreover, the CRISPR Cas-4 like activity of the nuclease has recently been characterized. In this study, a recently isolated Mimivirus of lineage A with R349 gene lacking 3 of 4 repeats was demonstrated to be susceptible to Zamilon. To reinforce the importance of the R349 gene in the MIMIVIRE system, we developed and presented, for the first time to our knowledge, a protocol for Mimivirus genomic editing. By knocking out R349 gene in a Mimivirus lineage A, we observed the replication of Zamilon, indicating that this gene is critical in the resistance against this specific group of virophages.
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Affiliation(s)
- Said Mougari
- Unité MEPHI, Aix Marseille Université, IHU Institut Hospitalo-Universitaire Méditerranée Infection, Marseille, France
| | - Jonatas Abrahao
- Unité MEPHI, Aix Marseille Université, IHU Institut Hospitalo-Universitaire Méditerranée Infection, Marseille, France.,Laboratório de Vírus, Departamento de Microbiologia, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Graziele P Oliveira
- Laboratório de Vírus, Departamento de Microbiologia, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Jacques Y Bou Khalil
- Unité MEPHI, Aix Marseille Université, IHU Institut Hospitalo-Universitaire Méditerranée Infection, Marseille, France
| | - Bernard La Scola
- Unité MEPHI, Aix Marseille Université, IHU Institut Hospitalo-Universitaire Méditerranée Infection, Marseille, France
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