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1.
Syst Biol ; 69(1): 110-123, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31127947

RESUMO

Tailed bacteriophages are the most abundant and diverse viruses in the world, with genome sizes ranging from 10 kbp to over 500 kbp. Yet, due to historical reasons, all this diversity is confined to a single virus order-Caudovirales, composed of just four families: Myoviridae, Siphoviridae, Podoviridae, and the newly created Ackermannviridae family. In recent years, this morphology-based classification scheme has started to crumble under the constant flood of phage sequences, revealing that tailed phages are even more genetically diverse than once thought. This prompted us, the Bacterial and Archaeal Viruses Subcommittee of the International Committee on Taxonomy of Viruses (ICTV), to consider overall reorganization of phage taxonomy. In this study, we used a wide range of complementary methods-including comparative genomics, core genome analysis, and marker gene phylogenetics-to show that the group of Bacillus phage SPO1-related viruses previously classified into the Spounavirinae subfamily, is clearly distinct from other members of the family Myoviridae and its diversity deserves the rank of an autonomous family. Thus, we removed this group from the Myoviridae family and created the family Herelleviridae-a new taxon of the same rank. In the process of the taxon evaluation, we explored the feasibility of different demarcation criteria and critically evaluated the usefulness of our methods for phage classification. The convergence of results, drawing a consistent and comprehensive picture of a new family with associated subfamilies, regardless of method, demonstrates that the tools applied here are particularly useful in phage taxonomy. We are convinced that creation of this novel family is a crucial milestone toward much-needed reclassification in the Caudovirales order.


Assuntos
Caudovirales/classificação , Filogenia , Caudovirales/genética , Classificação , Genoma Viral/genética
2.
Phys Rev Lett ; 123(13): 138101, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31697512

RESUMO

Multipartite viruses have a genome divided into different disconnected viral particles. A majority of multipartite viruses infect plants; very few target animals. To understand why, we use a simple, network-based susceptible-latent-infectious-recovered model. We show both analytically and numerically that, provided that the average degree of the contact network exceeds a critical value, even in the absence of an explicit microscopic advantage, multipartite viruses have a lower threshold to colonizing network-structured populations compared to a well-mixed population. We further corroborate this finding on two-dimensional lattice networks, which better represent the typical contact structures of plants.


Assuntos
Modelos Biológicos , Vírus de Plantas/fisiologia , Viroses/transmissão , Viroses/virologia , Genoma Viral , Doenças das Plantas/virologia , Vírus de Plantas/genética , Vírion/genética , Vírion/fisiologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-31618377

RESUMO

Chikungunya virus (CHIKV) is an arbovirus that emerged in the Americas in 2013. Infection with CHIKV is symptomatic in most of the cases and patients can develop chronic arthralgia that lasts from months to years in over 40% of the cases. The East-Central-South Africa (ECSA) genotype was introduced in Brazil in 2014, in Bahia State. Here we report the circulation of the CHIKV ECSA genotype in Piaui State, Northeast Brazil, during the years 2016-2017. The phylogenetic analysis revealed a single introduction of this lineage probably in 2015 and its maintenance at least until 2017. This analysis has also demonstrated the proximity of this genotype with isolates from neighboring States, and its partial nucleotide sequence of the viral E1 gene revealed a synapomorphy synonyms. This finding highlights the spread of the ECSA genotype in Brazil and supports its circulation in the Brazilian Northeast.


Assuntos
Febre de Chikungunya/virologia , Vírus Chikungunya/genética , Genoma Viral/genética , Sequência de Bases , Brasil/epidemiologia , Febre de Chikungunya/epidemiologia , Surtos de Doenças , Genótipo , Humanos , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , África do Sul
4.
Arch Virol ; 164(12): 3141-3144, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31598844

RESUMO

In this study, we report a novel double-stranded RNA (dsRNA) virus, Beauveria bassiana partitivirus 3 (BbPV-3), derived from the entomogenous fungus Beauveria bassiana isolate RCEF5853 from China. The genome of BbPV-3, whose sequence was determined by metagenomic sequencing, RT-PCR, and RACE cloning, comprises two dsRNA genome segments that are 1,856 and 1,719 bp long. The first segment contains a single ORF (ORF-1) encoding a 584-amino-acid-long protein (66.05 kDa) with a conserved RNA-dependent RNA polymerase (RdRp) motif. The second segment also has a single ORF (ORF-2) encoding a 500-amino-acid-long coat protein (CP) (55.9 kDa). The CP and RdRp sequences showed highest identity of 43.4% and 60.2%, respectively, to those of Colletotrichum eremochloae partitivirus 1. Phylogenetic analysis of the RdRp domain of the polyprotein revealed that BbPV-3 grouped together with the members of the genus Epsilonpartitivirus. Hence, we proposed that Beauveria bassiana partitivirus 3 is a novel member of the proposed genus Epsilonpartitivirus.


Assuntos
Beauveria/virologia , Micovírus/isolamento & purificação , Genoma Viral , Vírus de RNA/isolamento & purificação , Sequência de Bases , China , Micovírus/classificação , Micovírus/genética , Filogenia , RNA Replicase/genética , Vírus de RNA/classificação , Vírus de RNA/genética , RNA Viral/genética , Proteínas Virais/genética , Sequenciamento Completo do Genoma
5.
Arch Virol ; 164(12): 3027-3034, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31598845

RESUMO

The rate of evolution of viral genomes is a fundamental parameter for understanding the origin and spread of epidemics. For instance, molecular dating is one of the many practical outcomes of evolutionary rate estimation. In this sense, the rate of evolution of ZIKV merits attention, because it has been shown to be higher than the average rate reported for other flaviviruses. It has been hypothesized that the higher rate of ZIKV evolution is due to a bias related to the analysis of sequences collected within a short time range, which would increase the chance of sampling slightly deleterious nucleotide polymorphisms. To investigate this hypothesis, we assembled datasets with different ranges of sampling times and also decomposed the ZIKV evolutionary rate into synonymous and non-synonymous rates. Our results demonstrated that the rate of ZIKV evolution is time dependent and that the observed increase in short-term rates is largely accounted for by a higher non-synonymous rate, suggesting the presence of slightly deleterious variants not yet eliminated by purifying selection. On the other hand, we show that synonymous rates were less impacted by the range of sampling times, generating timescales with reduced uncertainty. We conclude that, for inferring the ZIKV timescale and reconstructing the history of epidemics, synonymous changes are the most appropriate substitution type to be examined. We were able to obtain ZIKV divergence times that were time independent and exhibited greater precision than previous estimates. This observation should also hold for other serially sampled fast-evolving pathogens with evidence of time dependence of evolutionary rates.


Assuntos
Evolução Molecular , Infecção por Zika virus/virologia , Zika virus/genética , Genoma Viral , Humanos , Cinética , Filogenia , Zika virus/química , Zika virus/classificação , Zika virus/isolamento & purificação
6.
Zhonghua Gan Zang Bing Za Zhi ; 27(8): 610-614, 2019 Aug 20.
Artigo em Chinês | MEDLINE | ID: mdl-31594078

RESUMO

Objective: To determine whether single-stranded guided RNA (gRNA) and Cas9 protein exist in the exosome secreted by cells transfected with CRISPR/Cas9 expression plasmid. Furthermore, to explore whether CRISPR/Cas9 system can edit target genes of peripheral cells through the intercellular transmission of exosomes. Methods: (1) The CRISPR/Cas9 expression plasmid was transfected into HuH7 cells. The supernatant was collected and the exosomes were concentrated and purified by differential centrifugation. The morphology and particle size of exosomes were determined by electronic microscopy and Malvern laser scatter granulometry. Reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting were used to detect the levels of gRNA and Cas9 protein. (2) HuH7 cells transfected with pBB4.5 1.2×HBV and HBV specific CRISPR/Cas9 expression plasmids were co-cultured. After 2 days, HBV DNA was extracted and sequenced by PCR. Results: There were not only full-length gRNA and Cas9 protein in the exosomes of Huh7 cells transfected with CRISPR / Cas9 expression plasmid. In addition, gene-editing functions were delivered between the cells to achieve the destruction of HBV genome of surrounding cells. Conclusion: The CRISPR-Cas9 gene-editing system has the potential to deliver exosomes between cells via carrying functional gRNA and Cas9 proteins. This phenomenon hints that we are in the process of using the CRISPR/Cas9 system for gene therapy. Therefore, it is necessary to consider the potential effects of exosomes-carried gRNA and Cas9 proteins on the surrounding cells of the distal tubules.


Assuntos
Sistemas CRISPR-Cas , Exossomos , Vírus da Hepatite B/genética , Linhagem Celular , Genoma Viral , Humanos , Transfecção
7.
Arch Virol ; 164(12): 3089-3093, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31595357

RESUMO

The phage vB_BthS-HD29phi infecting Bacillus thuringiensis strain HD29 was isolated and purified. The morphology of the phage showed that it belongs to the family Siphoviridae. The phage genome was 32,181 bp in length, comprised linear double-stranded DNA with an average G + C content of 34.9%, and exhibited low similarity to known phage genomes. Genomic and phylogenetic analysis revealed that vB_BthS-HD29phi is a novel phage. In total, 50 putative ORFs were predicted in the phage genome, and only 18 ORFs encoded proteins with known functions. This article reports the genome sequence of a new tailed phage and increases the known genetic diversity of tailed phages.


Assuntos
Fagos Bacilares/genética , Bacillus thuringiensis/virologia , Genoma Viral , Siphoviridae/genética , Fagos Bacilares/classificação , Fagos Bacilares/isolamento & purificação , Composição de Bases , Sequência de Bases , DNA Viral/genética , Variação Genética , Filogenia , Siphoviridae/classificação , Siphoviridae/isolamento & purificação , Sequenciamento Completo do Genoma
8.
Plant Dis ; 103(11): 2920-2924, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31567059

RESUMO

Papaya ringspot virus (PRSV) is the major constraint to papaya (Carica papaya) production in Bangladesh. Disease symptoms occurred in 90 to 100% of the plants surveyed. Full-length genomes of PRSV strains from severely infected papaya plants were determined using the Illumina NextSeq 500 platform, followed by Sanger DNA sequencing of viral genomes obtained by reverse-transcription PCR(RT-PCR). The genome sequences of two distinct PRSV strains, PRSV BD-1 (10,300 bp) and PRSV BD-2 (10,325 bp) were 74 and 83% identical to each other, respectively, at the nucleotide and amino acid levels. PRSV BD-1 and PRSV BD-2 were 74 to 75% and 79 to 88% identical, respectively, to other full-length PRSV sequences at the nucleotide level. Based on phylogenetic analysis, PRSV BD-2 was most closely related to PRSV-Meghalaya (MF356497) from papaya in India. PRSV BD-1 formed a branch distinct from the other PRSV sequences based on nucleotide and amino acid sequence comparisons. Comparisons of the genome sequences of these two strains with other sequenced PRSV genomes indicated two putative recombination events in PRSV BD-2. One recombinant event contained a 2,766-nucleotide fragment highly identical to PRSV-Meghalaya (MF356497). The other recombinant event contained a 5,105-nucleotide fragment highly identical to PRSV-China (KY933061). The occurrence rates of PRSV BD-1 and PRSV BD-2 in the sampled areas of Bangladesh were approximately 19 and 69%, respectively. Plants infected with both strains (11%) exhibited more severe symptoms than plants infected with either strain alone. The full-length genome sequences of these new PRSV strains and their distribution provide important information regarding the dynamics of papaya ringspot virus infections in papaya in Bangladesh.


Assuntos
Carica , Filogenia , Potyvirus , Bangladesh , Carica/virologia , China , Genoma Viral/genética , Índia , Doenças das Plantas/virologia , Potyvirus/classificação , Potyvirus/genética
9.
Arch Virol ; 164(12): 3145-3149, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31616995

RESUMO

A novel virus with a (+) single-stranded RNA genome was detected by high-throughput sequencing (HTS) in a sample of grapevine (Vitis vinifera) cv. Kizil Sapak (sample/isolate 127) that originated from Turkmenistan. The complete genome of the virus, tentatively named "grapevine Kizil Sapak virus" (GKSV), is 7,604 nucleotides in length, excluding the poly(A) tail. The genome organization of GKSV, encoded genes, and sequence domains are typical for members of the family Betaflexiviridae, specifically those belonging to the subfamily Trivirinae. Phylogenetic analysis placed GKSV within the subfamily Trivirinae, in the same clade as fig latent virus 1 (FLV-1) but distinct from the clades formed by members of other genera. A comparative analysis of GKSV-127 with the HTS-derived sequences obtained from two additional isolates showed that they are genetic variants of the same virus species. Based on current ICTV species and genus demarcation criteria, and the results of the sequence and phylogenetic analyses, we propose that GKSV and FLV-1 represent a new genus within the subfamily Trivirinae.


Assuntos
Flexiviridae/genética , Flexiviridae/isolamento & purificação , Doenças das Plantas/virologia , Vitis/virologia , Flexiviridae/classificação , Genoma Viral , Genômica , Fases de Leitura Aberta , Filogenia
10.
Mem Inst Oswaldo Cruz ; 114: e190219, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31644704

RESUMO

Human bocaviruses (HBoV) are mainly associated with respiratory and gastroenteric infections. These viruses belong to the family Parvoviridae, genus Bocaparvovirus and are classified in four subtypes (HBoV1-4). Recombination and point mutation have been described as basis of parvovirus evolution. In this study three viral sequences were obtained from positives HBoV sewage samples collected in two Uruguayan cities and were characterised by different methods as recombinant strains. This recombination event was localised in the 5' end of VP1 gene and the parental strains belonged to subtypes 3 and 4. These three Uruguayan strains are identical at the nucleotide sequences in the analysed genome region of the virus. As far as we known, this study represents the first detection of HBoV recombinants strains in the Americas.


Assuntos
Genoma Viral , Bocavirus Humano/genética , Infecções por Parvoviridae/virologia , Sequência de Bases , Bocavirus Humano/isolamento & purificação , Humanos , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Uruguai
11.
Arch Virol ; 164(12): 3157-3160, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31641840

RESUMO

Here, we report a novel virulent P2-like bacteriophage, R18C, isolated from rabbit faeces, which, in addition to Escherichia coli K-12 strains, was able to be propagated on Citrobacter rodentium strain ICC169 and a range of Shigella sonnei strains with high efficiency of plating (EOP). It represents the first lytic bacteriophage originating from rabbit and the first infectious P2-like phage of animal origin. In the three characteristic moron-containing regions of P2-like phages, R18C contains genes with unknown function that have so far only been found in cryptic P2-like prophages.


Assuntos
Bacteriófagos/isolamento & purificação , Citrobacter rodentium/virologia , Coelhos/microbiologia , Shigella sonnei/virologia , Animais , Bacteriófagos/classificação , Bacteriófagos/genética , Citrobacter rodentium/fisiologia , Fezes/virologia , Genoma Viral , Prófagos/classificação , Prófagos/genética , Prófagos/isolamento & purificação , Shigella sonnei/fisiologia
12.
Arch Virol ; 164(12): 3065-3071, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31549303

RESUMO

Tombusviruses are generally considered plant viruses. A novel tombus-/carmotetravirus-like RNA virus was identified in a faecal sample and blood and muscle tissues from a wild northern white-breasted hedgehog (Erinaceus roumanicus). The complete genome of the virus, called H14-hedgehog/2015/HUN (GenBank accession number MN044446), is 4,118 nucleotides in length with a readthrough stop codon of type/group 1 in ORF1 and lacks a poly(A) tract at the 3' end. The predicted ORF1-RT (RdRp) and the capsid proteins had low (31-33%) amino acid sequence identity to unclassified tombus-/noda-like viruses (Hubei tombus-like virus 12 and Beihai noda-like virus 10), respectively, discovered recently in invertebrate animals. An in vivo experimental plant inoculation study showed that an in vitro-transcribed H14-hedgehog/2015/HUN viral RNA did not replicate in Nicotiana benthamiana, Chenopodium quinoa, or Chenopodium murale, the most susceptible hosts for plant-origin tombusviruses.


Assuntos
Ouriços-Cacheiros/virologia , Análise de Sequência de RNA/métodos , Tombusvirus/classificação , Animais , Fezes/virologia , Tamanho do Genoma , Genoma Viral , Especificidade de Hospedeiro , Músculos/virologia , Filogenia , Tombusvirus/genética , Tombusvirus/isolamento & purificação
13.
DNA Cell Biol ; 38(11): 1257-1268, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31553224

RESUMO

Recent analyses suggest bacterial and/or mitochondrion-like ancestry for giant viruses (Megavirales sensu latu): amoeban mitochondrial gene arrangements resemble those of their candidate homologs in megaviral genomes. This presumed ancestral synteny decreases with genome size across megaviral families at large and within Poxviridae. In this study, analyses focus on Phycodnaviridae, a polyphyletic group of giant viruses infecting Haplophyta, Stramenopiles, and other algae, using syntenies between algal mitogene arrangements and chloroplast genomes and Rickettsia prowazekii as positive controls. Mitogene alignment qualities with Rickettsia are much higher than with viral genomes. Mitogenome synteny with some viruses is higher, for others lower than with Rickettsia, despite lower alignments qualities. In some algae, syntenies among cohosted chloroplast, virus, and mitochondrion are higher, in others lower than expected. This suggests gene order coevolution in cohosted genomes, different coregulations of organelle metabolisms for different algae, and viral mitogenome mimicry, to hijack organelle-committed cellular resources and/or escape cellular defenses/genetic immunity systems. This principle might explain high synteny between human mitochondria and the pathogenic endocellular alphaproteobacterium R. prowazekii beyond common ancestry. Results indicate that putative bacteria/mitochondrion-like genomic ancestors of Phycodnaviridae originated before or at the mitochondrion-bacteria split, and ulterior functional constraints on gene arrangements of cohosted genomes.


Assuntos
Cloroplastos/genética , Evolução Molecular , Mitocôndrias/genética , Mimetismo Molecular/fisiologia , Phycodnaviridae/genética , Sintenia/genética , Imunidade Adaptativa/genética , Genoma Mitocondrial/genética , Genoma Viral/genética , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Evasão da Resposta Imune/genética , Organelas/genética , Filogenia , Análise de Sequência de DNA
14.
Arch Virol ; 164(12): 3127-3131, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31559494

RESUMO

A cytorhabdovirus, tentatively named "strawberry-associated virus 1" (SaV1), was identified in strawberry (Fragaria ananassa Duch.), and its complete genome sequence was determined. Its negative-sense single-stranded RNA genome is composed of 14,159 nucleotides and contains eight open reading frames (ORFs) in the canonical order 3'-N-P-P3-M-G-P6-P7-L-5. The ORFs are separated by conserved intergenic sequences, and the genome coding region is flanked by 3' and 5' untranslated regions of 179 and 856 nt, respectively. SaV1 N and L genes shares 32-57% and 38-64% amino acid sequence identity with those of nine reported cytorhabdoviruses, respectively. Phylogenetic analysis showed that SaV1 clustered with high confidence with representative cytorhabdoviruses and is most closely related to tomato yellow mottle-associated virus. There are two additional small genes of unknown function between the G and L genes. We propose that SaV1 should be considered a member of a novel species in the genus Cytorhabdovirus, family Rhabdoviridae.


Assuntos
Fragaria/virologia , Genoma Viral , Doenças das Plantas/virologia , Rhabdoviridae/genética , DNA Intergênico/genética , Fases de Leitura Aberta , Filogenia , Rhabdoviridae/classificação , Rhabdoviridae/isolamento & purificação , Proteínas Virais/genética , Sequenciamento Completo do Genoma
15.
Arch Virol ; 164(11): 2819-2822, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31482204

RESUMO

A recent study by Ghosh et al. compared the gut microbiomes of 20 preschool children from India and found an association between the gut microbiome and the nutritional status of the child. Here, we explored these metagenomes for the presence of genomic signatures of prokaryotic and eukaryotic viruses. Several of the viral signatures found in all 20 metagenomes belonged to giant viruses (GVs). In addition, we found hits for bacteriophages to several major human pathogens, including Shigella, Salmonella, Escherichia, and Enterobacter. Concurrently, we also detected several antibiotic resistance genes (ARGs) in the metagenomes. All of the ARGs detected in this study (beta-lactam, macrolide, metronidazole, and tetracycline) are associated with mobile genetic elements (MGEs) and have been reported to cause high levels of resistance to their respective antibiotics. Despite recent reports of giant viruses and their genomic signatures in gut microbiota, their role in human physiology remains poorly understood. The effect of cooccurrence of ARGs and GVs in the gut needs further investigation.


Assuntos
Bacteriófagos/genética , Microbioma Gastrointestinal/genética , Genoma Viral/genética , Vírus Gigantes/genética , Metagenoma/genética , Pré-Escolar , Resistência Microbiana a Medicamentos/genética , Enterobacter/genética , Escherichia/virologia , Vírus Gigantes/isolamento & purificação , Humanos , Índia , Sequências Repetitivas Dispersas/genética , Salmonella/virologia , Shigella/virologia
16.
Arch Virol ; 164(11): 2837-2841, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31494776

RESUMO

Since January 2019, abnormal molting has been observed frequently in approximately 40-day-old Pekin ducks in China. To investigate the possible involvement of a virus, we tested the prevalence of duck circovirus (DuCV), goose hemorrhagic polyomavirus (GHPyV), and goose parvovirus (GPV) in 11 molt cases in two provinces. GPV was detected in all cases, particularly in all samples collected from the feather area. The complete genome sequences of three GPV strains were determined and found to have 52 nucleotide changes relative to GPVs associated with short beak and dwarfism syndrome of Pekin ducks. These data will enhance our understanding of GPV diversity and outcomes of GPV infection in Pekin ducks.


Assuntos
Patos/virologia , Gansos/virologia , Muda/fisiologia , Parvovirinae/isolamento & purificação , Doenças das Aves Domésticas/virologia , Animais , China/epidemiologia , Circovirus/genética , Circovirus/isolamento & purificação , Genoma Viral/genética , Parvovirinae/genética , Polyomavirus/genética , Polyomavirus/isolamento & purificação , Doenças das Aves Domésticas/epidemiologia
17.
Arch Virol ; 164(11): 2843-2848, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31494777

RESUMO

The Cooper and Los Angeles (LA) strains were the two original respiratory strains of bovine herpesvirus type 1.1 (BoHV-1.1) isolated in the 1950s from cattle with infectious bovine rhinotracheitis. We report the complete genome sequence for the BoHV-1.1 LA strain and compare it to the prototype Cooper strain and six wild-type BoHV-1.1 isolates. A nucleotide sequence divergence of 0.74% was noted across the two complete genomes, caused by 19 single-nucleotide polymorphisms (SNPs) involving 12 genes and insertions/deletions that primarily affected the number of repeats within reiterated repeat regions of the genome. Phylogenetic analysis revealed that Cooper and LA strains are genetically the most ancient strains from which all of the more-recently isolated field strains of BoHV-1.1 evolved.


Assuntos
Genoma Viral/genética , Infecções por Herpesviridae/veterinária , Herpesvirus Bovino 1/genética , Rinotraqueíte Infecciosa Bovina/virologia , Animais , Sequência de Bases , Bovinos , Doenças dos Bovinos/virologia , Genótipo , Herpesvirus Bovino 1/classificação , Polimorfismo de Nucleotídeo Único/genética , Análise de Sequência de DNA , Sequenciamento Completo do Genoma
18.
Arch Virol ; 164(11): 2887-2890, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31494778

RESUMO

The complete genome sequence of a novel megrivirus of the family Picornaviridae was determined from nucleic acid extracted from a pool of six faecal specimens of Adélie penguins. The samples were collected near Bellingshausen Station, King George Island of the South Shetland Islands, Antarctica. Penguin megrivirus is the first megrivirus with a predicted L protein. It has an L-3-5-4 genome layout, a type IV IRES, and a long 3' untranslated region of 668 nt.


Assuntos
Genoma Viral/genética , Picornaviridae/genética , Spheniscidae/virologia , Regiões 3' não Traduzidas/genética , Animais , Regiões Antárticas , Filogenia , Picornaviridae/classificação , Picornaviridae/isolamento & purificação
19.
Arch Virol ; 164(11): 2829-2836, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31486908

RESUMO

The complete sequence of the medium (M) and small (S) RNA genome segments were determined for twelve isolates of impatiens necrotic spot virus from eight plant species. The M- and S-RNAs of these isolates shared 97-99% and 93-98% nucleotide sequence identity, respectively, with the corresponding full-length sequences available in public databases. Phylogenetic analysis based on the M- or S-RNA sequences showed incongruence in the phylogenetic position of some isolates, suggesting intraspecies segment reassortment. The lack of phylogenetic discordance in individual and concatenated sequences of individual genes encoded by M- or S-RNAs suggests that segment reassortment rather than recombination is driving evolution of these INSV isolates.


Assuntos
RNA Viral/genética , Vírus Reordenados/genética , Tospovirus/genética , Sequência de Bases , Genoma Viral/genética , Plantas/virologia , Análise de Sequência de RNA , Tospovirus/isolamento & purificação
20.
Arch Virol ; 164(11): 2849-2852, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31502078

RESUMO

Arracacha virus B type (AVB-T) and oca (AVB-O) strains from arracacha (Arracacia xanthorrhiza) and oca (Oxalis tuberosa) samples collected in 1975 and two additional isolates obtained from arracacha (AVB-PX) and potato (AVB-6A) in Peru in 1976 and 1978, respectively, were studied. In its host responses and serological properties, AVB-PX most resembled AVB-T, whereas AVB-6A most resembled AVB-O. Complete genomic sequences of the RNA-1 and RNA-2 of each isolate were obtained following high-throughput sequencing of RNA extracts from isolates preserved for 38 (AVB-PX) or 32 (the other 3 isolates) years, and compared with a genomic sequence of AVB-O obtained previously (PV-0082). RNA-2 was unexpectedly divergent compared to RNA-1, with the nucleotide (nt) sequence identity of different AVB isolates varying by up to 76% (RNA-2) and 89% (RNA-1). The coat protein amino acid sequences were the most divergent, with AVB-O and AVB-6A having only 68% identity to AVB-T and AVB-PX. Since the RNA2 sequence differences between the two isolate groupings also coincided with host range, symptom, and serological differences, AVB demonstrates considerable intraspecific divergence.


Assuntos
Genoma Viral/genética , RNA Viral/genética , Secoviridae/genética , Sequência de Aminoácidos , Sequência de Bases , Proteínas do Capsídeo/genética , Sequenciamento de Nucleotídeos em Larga Escala , Magnoliopsida/virologia , Oxalidaceae/virologia , Peru , Doenças das Plantas/virologia , Secoviridae/isolamento & purificação , Solanum tuberosum/virologia
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