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1.
Open Access Emerg Med ; 16: 101-105, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38706755

RESUMEN

Sixth Disease (roseola infantum) and its primary causative agent, HHV-6, share names that numerically concur. This article examines and answers the question of whether that correspondence is by design or coincidental by briefly reviewing the history and nomenclature of the HHV viruses and the classic febrile rashes of childhood while highlighting some clinical and microbiologic features of HHV-6 infection.

2.
Biomolecules ; 13(1)2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-36671495

RESUMEN

The evaluation of the evolutionary relationships is exceptionally important for the taxonomy of viruses, which is a rapidly expanding area of research. The classification of viral groups belonging to the realm Duplodnaviria, which include tailed bacteriophages, head-tailed archaeal viruses and herpesviruses, has undergone many changes in recent years and continues to improve. One of the challenging tasks of Duplodnaviria taxonomy is the classification of high-ranked taxa, including families and orders. At the moment, only 17 of 50 families have been assigned to orders. The evaluation of the evolutionary relationships between viruses is complicated by the high level of divergence of viral proteins. However, the development of structure prediction algorithms, including the award-winning AlphaFold, encourages the use of the results of structural predictions to clarify the evolutionary history of viral proteins. In this study, the evolutionary relationships of two conserved viral proteins, the major capsid protein and terminase, representing different viruses, including all classified Duplodnaviria families, have been analysed using AlphaFold modelling. This analysis has been undertaken using structural comparisons and different phylogenetic methods. The results of the analyses mainly indicated the high quality of AlphaFold modelling and the possibility of using the AlphaFold predictions, together with other methods, for the reconstruction of the evolutionary relationships between distant viral groups. Based on the results of this integrated approach, assumptions have been made about refining the taxonomic classification of bacterial and archaeal Duplodnaviria groups, and problems relating to the taxonomic classification of Duplodnaviria have been discussed.


Asunto(s)
Genoma Viral , Virus , Humanos , Filogenia , Virus/genética , Evolución Biológica , Proteínas Virales/química
3.
Biol Rev Camb Philos Soc ; 98(2): 584-602, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36366773

RESUMEN

During the last century enormous progress has been made in the understanding of biological diversity, involving a dramatic shift from macroscopic to microscopic organisms. The question now arises as to whether the Natural System introduced by Carl Linnaeus, which has served as the central system for organizing biological diversity, can accommodate the great expansion of diversity that has been discovered. Important discoveries regarding biological diversity have not been fully integrated into a formal, coherent taxonomic system. In addition, because of taxonomic challenges and conflicts, various proposals have been made to abandon key aspects of the Linnaean system. We review the current status of taxonomy of the living world, focussing on groups at the taxonomic level of phylum and above. We summarize the main arguments against and in favour of abandoning aspects of the Linnaean system. Based on these considerations, we conclude that retaining the Linnaean Natural System provides important advantages. We propose a relatively small number of amendments for extending this system, particularly to include the named rank of world (Latin alternative mundis) formally to include non-cellular entities (viruses), and the named rank of empire (Latin alternative imperium) to accommodate the depth of diversity in (unicellular) eukaryotes that has been uncovered. We argue that in the case of both the eukaryotic domain and the viruses the cladistic approach intrinsically fails. However, the resulting semi-cladistic system provides a productive way forward that can help resolve taxonomic challenges. The amendments proposed allow us to: (i) retain named taxonomic levels and the three-domain system, (ii) improve understanding of the main eukaryotic lineages, and (iii) incorporate viruses into the Natural System. Of note, the proposal described herein is intended to serve as the starting point for a broad scientific discussion regarding the modernization of the Linnaean system.


Asunto(s)
Biodiversidad , Eucariontes , Filogenia
4.
Int J Mol Sci ; 22(19)2021 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-34638693

RESUMEN

Pseudomonas phage MD8 is a temperate phage isolated from the freshwater lake Baikal. The organisation of the MD8 genome resembles the genomes of lambdoid bacteriophages. However, MD8 gene and protein sequences have little in common with classified representatives of lambda-like phages. Analysis of phage genomes revealed a group of other Pseudomonas phages related to phage MD8 and the genomic layout of MD8-like phages indicated extensive gene exchange involving even the most conservative proteins and leading to a high degree of genomic mosaicism. Multiple horizontal transfers and mosaicism of the genome of MD8, related phages and other λ-like phages raise questions about the principles of taxonomic classification of the representatives of this voluminous phage group. Comparison and analysis of various bioinformatic approaches applied to λ-like phage genomes demonstrated different efficiency and contradictory results in the estimation of genomic similarity and relatedness. However, we were able to make suggestions for the possible origin of the MD8 genome and the basic principles for the taxonomic classification of lambdoid phages. The group comprising 26 MD8-related phages was proposed to classify as two close genera belonging to a big family of λ-like phages.


Asunto(s)
Bacteriófago lambda , Genes Virales , Fagos Pseudomonas , Bacteriófago lambda/clasificación , Bacteriófago lambda/genética , Fagos Pseudomonas/clasificación , Fagos Pseudomonas/genética
5.
Front Microbiol ; 12: 704052, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34349745

RESUMEN

Double-stranded DNA viruses of the realm Varidnaviria (formerly PRD1-adenovirus lineage) are characterized by homologous major capsid proteins (MCPs) containing one (kingdom: Helvetiavirae) or two ß-barrel domains (kingdom: Bamfordvirae) known as the jelly roll folds. Most of them also share homologous packaging ATPases (pATPases). Remarkably, Varidnaviria infect hosts from the three domains of life, suggesting that these viruses could be very ancient and share a common ancestor. Here, we analyzed the evolutionary history of Varidnaviria based on single and concatenated phylogenies of their MCPs and pATPases. We excluded Adenoviridae from our analysis as their MCPs and pATPases are too divergent. Sphaerolipoviridae, the only family in the kingdom Helvetiavirae, exhibit a complex history: their MCPs are very divergent from those of other Varidnaviria, as expected, but their pATPases groups them with Bamfordvirae. In single and concatenated trees, Bamfordvirae infecting archaea were grouped with those infecting bacteria, in contradiction with the cellular tree of life, whereas those infecting eukaryotes were organized into three monophyletic groups: the Nucleocytoviricota phylum, formerly known as the Nucleo-Cytoplasmic Large DNA Viruses (NCLDVs), Lavidaviridae (virophages) and Polintoviruses. Although our analysis mostly supports the recent classification proposed by the International Committee on Taxonomy of Viruses (ICTV), it also raises questions, such as the validity of the Adenoviridae and Helvetiavirae ranking. Based on our phylogeny, we discuss current hypotheses on the origin and evolution of Varidnaviria and suggest new ones to reconcile the viral and cellular trees.

6.
Viruses ; 12(12)2020 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-33291220

RESUMEN

The International Virus Bioinformatics Meeting 2020 was originally planned to take place in Bern, Switzerland, in March 2020. However, the COVID-19 pandemic put a spoke in the wheel of almost all conferences to be held in 2020. After moving the conference to 8-9 October 2020, we got hit by the second wave and finally decided at short notice to go fully online. On the other hand, the pandemic has made us even more aware of the importance of accelerating research in viral bioinformatics. Advances in bioinformatics have led to improved approaches to investigate viral infections and outbreaks. The International Virus Bioinformatics Meeting 2020 has attracted approximately 120 experts in virology and bioinformatics from all over the world to join the two-day virtual meeting. Despite concerns being raised that virtual meetings lack possibilities for face-to-face discussion, the participants from this small community created a highly interactive scientific environment, engaging in lively and inspiring discussions and suggesting new research directions and questions. The meeting featured five invited and twelve contributed talks, on the four main topics: (1) proteome and RNAome of RNA viruses, (2) viral metagenomics and ecology, (3) virus evolution and classification and (4) viral infections and immunology. Further, the meeting featured 20 oral poster presentations, all of which focused on specific areas of virus bioinformatics. This report summarizes the main research findings and highlights presented at the meeting.


Asunto(s)
Biología Computacional , Virus ARN/genética , Virología , COVID-19 , Congresos como Asunto , Evolución Molecular , Genoma Viral , Humanos , Metagenómica , Virus ARN/patogenicidad
7.
Infect Genet Evol ; 81: 104239, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32058075

RESUMEN

The limited knowledge on Papillomavirus diversity (particularly in wild animal species) influences the accuracy of PVs phylogeny and their evolutionary history, and hinders the comprehension of PVs pathogenicity, especially the mechanism of virus - related cancer progression. This study reports the identification of Leopardus wiedii Papillomavirus type 1 (LwiePV1), the first PV type within Lambdapapillomavirus in a Leopardus host. LwiePV1 full genome sequencing allowed the investigation of its taxonomic position and phylogeny. Based on results, LwiePV1 should be assigned to a novel PV species providing evidence for a polyphyletic origin of feline lambda PVs, and representing an exception to codivergence between feline lambda PVs and their hosts. Results improve our knowledge on PV diversity and pave the way to future studies investigating biological and evolutionary features of animal PVs.


Asunto(s)
Felidae/virología , Lambdapapillomavirus/genética , Animales , Animales Salvajes/virología , Evolución Biológica , Genoma Viral/genética , Filogenia
8.
Viruses ; 11(12)2019 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-31835553

RESUMEN

Bacteriophages of the significant veterinary pathogen Staphylococcus pseudintermedius are rarely described morphologically and genomically in detail, and mostly include phages of the Siphoviridae family. There is currently no taxonomical classification for phages of this bacterial species. Here we describe a new phage designated vB_SpsS_QT1, which is related to phage 2638A originally described as a Staphylococcus aureus phage. Propagating strain S. aureus 2854 of the latter was reclassified by rpoB gene sequencing as S. pseudintermedius 2854 in this work. Both phages have a narrow but different host range determined on 54 strains. Morphologically, both of them belong to the family Siphoviridae, share the B1 morphotype, and differ from other staphylococcal phage genera by a single long fibre at the terminus of the tail. The complete genome of phage vB_SpsS_QT1 was sequenced with the IonTorrent platform and expertly annotated. Its linear genome with cohesive ends is 43,029 bp long and encodes 60 predicted genes with the typical modular structure of staphylococcal siphophages. A global alignment found the genomes of vB_SpsS_QT1 and 2638A to share 84% nucleotide identity, but they have no significant similarity of nucleotide sequences with other phage genomes available in public databases. Based on the morphological, phylogenetic, and genomic analyses, a novel genus Fibralongavirus in the family Siphoviridae is described with phage species vB_SpsS_QT1 and 2638A.


Asunto(s)
Siphoviridae/clasificación , Staphylococcus/virología , Genes Virales , Genoma Viral , Genómica/métodos , Especificidad del Huésped , Filogenia , Siphoviridae/ultraestructura , Virión/ultraestructura , Replicación Viral
9.
Viruses ; 11(5)2019 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-31060321

RESUMEN

The Third Annual Meeting of the European Virus Bioinformatics Center (EVBC) took place in Glasgow, United Kingdom, 28-29 March 2019. Virus bioinformatics has become central to virology research, and advances in bioinformatics have led to improved approaches to investigate viral infections and outbreaks, being successfully used to detect, control, and treat infections of humans and animals. This active field of research has attracted approximately 110 experts in virology and bioinformatics/computational biology from Europe and other parts of the world to attend the two-day meeting in Glasgow to increase scientific exchange between laboratory- and computer-based researchers. The meeting was held at the McIntyre Building of the University of Glasgow; a perfect location, as it was originally built to be a place for "rubbing your brains with those of other people", as Rector Stanley Baldwin described it. The goal of the meeting was to provide a meaningful and interactive scientific environment to promote discussion and collaboration and to inspire and suggest new research directions and questions. The meeting featured eight invited and twelve contributed talks, on the four main topics: (1) systems virology, (2) virus-host interactions and the virome, (3) virus classification and evolution and (4) epidemiology, surveillance and evolution. Further, the meeting featured 34 oral poster presentations, all of which focused on specific areas of virus bioinformatics. This report summarizes the main research findings and highlights presented at the meeting.


Asunto(s)
Biología Computacional , Virosis/virología , Virus/química , Virus/genética , Animales , Bacteriófagos/clasificación , Bacteriófagos/genética , Bacteriófagos/aislamiento & purificación , Humanos , Filogenia , Virosis/veterinaria , Virus/aislamiento & purificación , Virus/metabolismo
10.
Adv Virus Res ; 100: 1-18, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29551132

RESUMEN

Virus classification deals with conceptual species classes that have viruses as their members. A virus species cannot be described but can only be defined by listing certain species-defining properties of its member. However, it is not possible to define a virus species by using a single species-defining property. The new 2013 official definition of virus species is not appropriate because it applies equally to virus genera. A nucleotide motif is a chemical part of a viral genome and is not a species-defining property that could be used for establishing new virus species. A virus classification based solely on nucleotide sequences is a classification of viral genomes and not of viruses. The variable distribution of species-defining properties of a polythetic species class is not itself a single common property of all the members of the class, since this would lead to the paradox that every polythetic class is also a monothetic one.


Asunto(s)
Virología , Virus/clasificación , Clasificación , Genoma Viral/genética , Especificidad de la Especie , Virus/química , Virus/genética
11.
Virology ; 510: 297-304, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28797947

RESUMEN

The bipartite alpha- and betapartitiviruses are recorded from a wide range of fungi and plants. Using a combination of dsRNA-enrichment, high-throughput shotgun sequencing and informatics, we report the occurrence of multiple new partitiviruses associated with mycorrhizal Ceratobasidium fungi, themselves symbiotically associated with a small wild population of Pterostylis sanguinea orchids in Australia, over two consecutive years. Twenty-one partial or near-complete sequences representing 16 definitive alpha- and betapartitivirus species, and further possible species, were detected from two fungal isolates. The majority of partitiviruses occurred in fungal isolates from both years. Two of the partitiviruses represent phylogenetically divergent forms of Alphapartitivirus, suggesting that they may have evolved under long geographical isolation there. We address the challenge of pairing the two genomic segments of partitiviruses to identify species when multiple partitiviruses co-infect a single host.


Asunto(s)
Basidiomycota/virología , Virus Fúngicos/clasificación , Virus Fúngicos/aislamiento & purificación , Orchidaceae/microbiología , Filogenia , Australia , Biología Computacional , Virus Fúngicos/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Estudios Longitudinales , Análisis de Secuencia de ADN
12.
Virology ; 511: 259-271, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28648249

RESUMEN

Members of the family Iridoviridae, collectively referred to as iridovirids, are large, double-stranded DNA-containing viruses that infect invertebrates and cold-blooded (ectothermic) vertebrates. Infections in the former often lead to massive levels of virus replication resulting in iridescence of the infected animal and ultimately death. Among the latter, infections target a variety of organs and are capable of causing high levels of morbidity and mortality among commercially and ecologically important fish and amphibian species. The viral replication strategy has been elucidated primarily through the study of frog virus 3 (FV3) with additional input from other iridovirids of ecological or commercial importance. Replication occurs within both nuclear and cytoplasmic compartments and involves synthesis of genome length and concatemeric DNA, extensive methylation of the viral genome (among vertebrate viruses only), coordinate expression of three classes of viral gene products, and formation of icosahedral virions within cytoplasmic viral assembly sites. Phylogenetic analyses delineate five genera within the family and suggest that members of the families Iridoviridae, Ascoviridae, and Marseilleviridae compromise a monophyletic lineage in which ascoviruses are most closely related to invertebrate iridoviruses.


Asunto(s)
Interacciones Huésped-Patógeno , Filogenia , Ranavirus/genética , Ranavirus/fisiología , Replicación Viral , Anfibios/virología , Animales , Peces/virología , Invertebrados/virología , Ranavirus/clasificación
13.
Commun Integr Biol ; 10(2): e1296614, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28451057

RESUMEN

Viral evolution is characterized by high rates of horizontal gene transfer and fast sequence divergence. Furthermore, there are no universal genes shared by all viruses. As a result, distant relationships among viruses are better represented by a network than by a tree. Here we discuss 3 network representations of the virus world with decreasing levels of complexity, from a multilayer network that integrates sequence conservation and patterns of gene sharing to a classic genome similarity network. As new tools for network analysis are developed, we expect that novel insights into virus evolution will result from the study of more complex representations of the virus world.

14.
Stud Hist Philos Biol Biomed Sci ; 59: 64-70, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26994934

RESUMEN

Early attempts in the 1960s at constructing a classification scheme for viruses were phenetic and focused on structural properties of the virion. Over time, the International Committee on the Taxonomy of Viruses (ICTV) has refined its definition of a virus species to include an appeal to evolutionary history. The current ICTV definition defines a viral species in terms of monophyly. The existence of prolific horizontal genetic transfer (HGT) among various groups of viruses presents a challenge to this definition. I argue that the proper response to this mode of evolution is to allow for radical pluralism. Some viruses can be members of more than one species; others don't form species at all and should be classified using new reticulate categories.


Asunto(s)
Especiación Genética , Virus/clasificación , Evolución Biológica , Transferencia de Gen Horizontal , Filogenia , Virus/genética
15.
Viruses ; 7(7): 3937-53, 2015 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-26193304

RESUMEN

Numbering in excess of 10 million per milliliter of water, it is now undisputed that aquatic viruses are one of the major factors shaping the ecology and evolution of Earth's microbial world. Nonetheless, environmental viral diversity and roles remain poorly understood. Here we report the first thorough characterization of a virus (designated TsV) that infects the coastal marine microalga Tetraselmis striata. Unlike previously known microalgae-infecting viruses, TsV is a small (60 nm) DNA virus, with a 31 kb genome. From a range of eight different strains belonging to the Chlamydomonadaceae family, TsV was only able to infect T. striata. Gene expression dynamics revealed an up-regulation of viral transcripts already 1 h post-infection (p.i.). First clear signs of infection were observed 24 h p.i., with the appearance of viral factories inside the nucleus. TsV assembly was exclusively nuclear. TsV-N1 genome revealed very different from previously known algae viruses (Phycodnaviridae). Putative function and/or homology could be resolved for only 9 of the 33 ORFs encoded. Among those was a surprising DNA polymerase type Delta (only found in Eukaryotes), and two genes with closest homology to genes from human parasites of the urogenital tract. These results support the idea that the diversity of microalgae viruses goes far beyond the Phycodnaviridae family and leave the door open for future studies on implications of microalgae viruses for human health.


Asunto(s)
Chlorophyta/virología , Phycodnaviridae/fisiología , Genoma Viral , Especificidad del Huésped , Humanos , Datos de Secuencia Molecular , Phycodnaviridae/genética , Phycodnaviridae/aislamiento & purificación , Filogenia
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