RESUMO
Enterovirus E (EV-E), a representative of the Picornaviridae family, endemically affects cattle across the world, typically causing subclinical infections. However, under favorable conditions, severe or fatal disorders of the respiratory, digestive, and reproductive systems may develop. There is no specific treatment for enterovirus infections in humans or animals, and only symptomatic treatment is available. The aim of this study was to determine the in vitro antiviral effect of bovine lactoferrin (bLF) against enterovirus E using virucidal, cytopathic effect inhibition, and viral yield reduction assays in MDBK cells. The influence of lactoferrin on the intracellular viral RNA level was also determined. Surprisingly, lactoferrin did not have a protective effect on cells, although it inhibited the replication of the virus during the adsorption and post-adsorption stages (viral titres reduced by 1-1.1 log). Additionally, a decrease in the viral RNA level in cells (by up to 75%) was observed. More detailed studies are needed to determine the mechanism of bovine lactoferrin effect on enterovirus E. However, this highly biocompatible protein ensures some degree of protection against infection by bovine enterovirus, which is particularly important for young animals that receive this protein in their mother's milk.
Assuntos
Infecções por Enterovirus , Enterovirus Bovino , Lactoferrina , Animais , Antivirais/farmacologia , Bovinos , Infecções por Enterovirus/tratamento farmacológico , Lactoferrina/farmacologia , RNA ViralRESUMO
BACKGROUND: Bovine viral diarrhea virus (BVDV) is a cause of substantial economic loss to the cattle industry worldwide, and there are currently no effective treatment or preventive measures. Bovine enterovirus (BEV) has a broad host range with low virulence and is a good candidate as a viral vaccine vector. In this study, we explored new insertion sites for the expression of exogenous genes in BEV, and developed a recombinant infectious cDNA clone for BEV BJ101 strain expressing BVDV E0 protein. METHODS: A recognition site for the viral proteinase 3Cpro was inserted in the GpBSK-BEV plasmid at the 2C/3A junction by overlapping PCR. Subsequently, the optimized full-length BVDV E0 gene was inserted to obtain the recombinant infectious plasmid GpBSK-BEV-E0. The rescued recombinant virus was obtained by transfection with linearized plasmid. Expression of BVDV E0 in the recombinant virus was confirmed by PCR, western blotting, and immunofluorescence analysis, and the genetic stability was tested in MDBK cells over 10 passages. We further tested the ability of the recombinant virus to induce an antibody response in mice infected with BVDV and immunized them with the recombinant virus and parental strain. RESULTS: The rescued recombinant virus rBEV-E0 was identified and confirmed by western blot and indirect immunofluorescence. The sequencing results showed that the recombinant virus remained stable for 10 passages without genetic changes. There was also no significant difference in growth dynamics and plaque morphology between the recombinant virus and parental virus. Mice infected with both recombinant and parental viruses produced antibodies against BEV VP1, while the recombinant virus also induced antibodies against BVDV E0. CONCLUSION: A new insertion site in the BEV vector can be used for the prevention and control of both BEV and BVDV, providing a useful tool for future research on the development of viral vector vaccines.
Assuntos
Anticorpos Antivirais/sangue , Infecções por Enterovirus/veterinária , Enterovirus Bovino/genética , Proteínas do Envelope Viral/imunologia , Vacinas Virais/imunologia , Animais , Bovinos , Linhagem Celular , Vírus da Diarreia Viral Bovina/genética , Vírus da Diarreia Viral Bovina/imunologia , Infecções por Enterovirus/prevenção & controle , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia , Proteínas do Envelope Viral/genética , Vacinas Virais/administração & dosagem , Vacinas Virais/genéticaRESUMO
Picornaviruses infect a wide range of mammals including livestock such as cattle and swine. As with other picornavirus genera such as Aphthovirus, there is emerging evidence of a significant economic impact of livestock infections caused by members of the genera Enterovirus and Kobuvirus. While the human-infecting enteroviruses and kobuviruses have been intensively studied during the past decades in great detail, research on livestock-infecting viruses has been mostly limited to the genomic characterization of the viral strains identified worldwide. Here, we extend our previous studies of the structure and function of the complexes composed of the non-structural 3A proteins of human-infecting enteroviruses and kobuviruses and the host ACBD3 protein and present a structural and functional characterization of the complexes of the following livestock-infecting picornaviruses: bovine enteroviruses EV-E and EV-F, porcine enterovirus EV-G, and porcine kobuvirus AiV-C. We present a series of crystal structures of these complexes and demonstrate the role of these complexes in facilitation of viral replication.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Infecções por Enterovirus/metabolismo , Enterovirus Bovino/patogenicidade , Enterovirus Suínos/patogenicidade , Kobuvirus/patogenicidade , Proteínas de Membrana/metabolismo , Infecções por Picornaviridae/metabolismo , Animais , Bovinos , Linhagem Celular , Infecções por Enterovirus/veterinária , Infecções por Enterovirus/virologia , Enterovirus Suínos/genética , Células HEK293 , Humanos , Kobuvirus/genética , Infecções por Picornaviridae/veterinária , Infecções por Picornaviridae/virologia , Suínos , Proteínas Virais/genética , Proteínas Virais/metabolismo , Replicação Viral/genéticaRESUMO
Full-length infectious cDNA clones for recombinant HY12 bovine enteroviruses designated as rHY12-3A-2-HA, rHY12-3A-3-HA, and rHY12-3A-9-HA were constructed by the insertion of an epitope from influenza virus hemagglutinin (HA) at the N-terminus of the HY12-encoded 3A protein at amino acid positions 2, 3, and 9. The recombinant HY12 viruses expressing the HA epitope were rescued and characterized using immunoperoxidase monolayer assay, western blotting, and electron microscopy. The three rescued recombinant marker viruses showed similar characteristics, such as TCID50 titer, plaque size, and growth properties, to those of parental rHY12 virus. Comparative analysis of the nucleotide sequences demonstrated the three recombinant marker viruses remained stable for 15 passages with no genetic changes. The recombinant viruses remained viable in various permissive cell lines, including BHK-21, Vero, and PK15 cells, suggesting that the insertion of the HA epitope tag had no effect on virus infectivity. Mice infected with the recombinant marker viruses and the parental virus produced anti-HY12-virus antibodies, while the recombinant marker viruses also produced anti-HA-epitope-tag antibodies. Taken together, these results demonstrate that HY12 viruses containing genetic markers may be useful tools for future investigations of the mechanisms of viral pathogenesis and virus replication, as well as for vaccine development.
Assuntos
Anticorpos Antivirais/imunologia , Enterovirus Bovino/genética , Enterovirus Bovino/imunologia , Epitopos/imunologia , Hemaglutininas/imunologia , Proteínas Virais/imunologia , Animais , Linhagem Celular , Chlorocebus aethiops , Cricetinae , Cães , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Hemaglutininas/genética , Células Madin Darby de Rim Canino , Camundongos , Camundongos Endogâmicos ICR , Suínos , Células Vero , Proteínas Virais/genéticaRESUMO
It is suggested that bovine enteroviruses (BEV) are involved in the aetiology of enteric infections, respiratory disease, reproductive disorders and infertility. In this study, bovine faecal samples collected in different Brazilian states were subjected to RNA extraction, reverse transcription-polymerase chain reaction analysis and partial sequencing of the 5'-terminal portion of BEV. One hundred and three samples were tested with an overall positivity of 14.5%. Phylogenetic analysis clustered these BEV Brazilian samples into the Enterovirus F clade. Our results bring an important update of the virus presence in Brazil and contribute to a better understanding of the distribution and characterisation of BEV in cattle.
Assuntos
Doenças dos Bovinos/virologia , Infecções por Enterovirus/veterinária , Enterovirus Bovino/isolamento & purificação , Animais , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Infecções por Enterovirus/epidemiologia , Infecções por Enterovirus/virologia , Enterovirus Bovino/genética , FilogeniaRESUMO
Bovine enterovirus (BEV) VP2 protein is a structural protein that plays an important role in inducing protective immunity in the host. The function of VP2 has been characterized, but there is little information on its B cell epitopes. Three monoclonal antibodies (mAbs) directed against BEV VP2 were generated and characterized from mice immunized with the recombinant VP2 protein. Three minimal linear epitopes 152FQEAFWLEDG161, 168LIYPHQ173, and 46DATSVD51 reactive to the three mAbs were identified using western blotting analysis. Three-dimensional model of the BEV-E virion and the VP2 monomer showed that epitope 152FQEAFWLEDG161 is exposed on surface of the virion and epitopes 46DATSVD51 and 168LIYPHQ173 are located inside the virion. Alignment of the amino acid sequences corresponding to the regions containing the three minimal linear epitopes in the VP2 proteins and their cross-reactivity with the three mAbs showed that epitope 168LIYPHQ173 is completely conserved in all BEV strains. Epitope 46DATSVD51 is highly conserved among BEV-E strains and partly conserved among BEV-F strains. However, epitope 152FQEAFWLEDG161 is not conserved among BEV-F strains. Using the mAbs of 3H4 and 1E10, we found that VP2 localized in the cytoplasm during viral replication and could be used to monitor the viral antigen in infected tissues using immunohistochemistry. A preliminary 3H4-epitope-based indirect ELISA allowed us to detect anti-BEV-strain-HY12 antibodies in mice. This study indicates that the three mAbs could be useful tools for investigating the structure and function of the viral VP2 protein and the development of serological diagnostic techniques for BEV infection.
Assuntos
Anticorpos Monoclonais/imunologia , Proteínas do Capsídeo/imunologia , Enterovirus Bovino/imunologia , Mapeamento de Epitopos , Epitopos de Linfócito B/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/imunologia , Proteínas do Capsídeo/química , Bovinos , Epitopos de Linfócito B/química , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Homologia de SequênciaRESUMO
The involvement of picornaviruses in calf diarrhoea was evaluated by the analysis of 127 faecal samples collected from diarrhoeic calves during 2014-2016. Virus detections were carried out by PCR using generic or specific primer pairs. One-third of the faecal samples (33.86%) were found to be positive for one or more of the studied viruses. Bovine kobuvirus was detected in 22.83%, bovine hungarovirus in 11.02%, while bovine enterovirus 1 in 5.51% of the samples. The sequences of the PCR products indicated the existence of novel variants in all the three virus species. When comparing the partial sequences, the nucleotide sequence identities between our newly detected viruses and those previously deposited to the GenBank ranged between 76 and 99%. Phylogenetic analyses revealed a novel lineage within the species Hunnivirus A. Our findings suggest that these viruses should be regarded as possible aetiological agents of calf diarrhoea. Based on the newly determined sequences, we designed and tested a new generic PCR primer set for the more reliable detection of bovine hungaroviruses. This is the first report on the molecular detection of the presence of bovine hungarovirus, bovine kobuvirus and bovine enterovirus 1 in the faecal samples of diarrhoeic calves in Turkey.
Assuntos
Doenças dos Bovinos/virologia , Diarreia/veterinária , Infecções por Picornaviridae/veterinária , Picornaviridae/isolamento & purificação , Animais , Bovinos , Diarreia/virologia , Enterovirus Bovino/genética , Enterovirus Bovino/isolamento & purificação , Kobuvirus/genética , Kobuvirus/isolamento & purificação , Picornaviridae/genética , Infecções por Picornaviridae/virologia , TurquiaRESUMO
Picornavirus Type 1 IRESs comprise five principal domains (dII-dVI). Whereas dV binds eIF4G, a conserved AUG in dVI was suggested to stimulate attachment of 43S ribosomal preinitiation complexes, which then scan to the initiation codon. Initiation on Type 1 IRESs also requires IRES trans-acting factors (ITAFs), and several candidates have been proposed. Here, we report the in vitro reconstitution of initiation on three Type 1 IRESs: poliovirus (PV), enterovirus 71 (EV71), and bovine enterovirus (BEV). All of them require eIF2, eIF3, eIF4A, eIF4G, eIF4B, eIF1A, and a single ITAF, poly(C) binding protein 2 (PCBP2). In each instance, initiation starts with binding of eIF4G/eIF4A. Subsequent recruitment of 43S complexes strictly requires direct interaction of their eIF3 constituent with eIF4G. The following events can differ between IRESs, depending on the stability of dVI. If it is unstructured (BEV), all ribosomes scan through dVI to the initiation codon, requiring eIF1 to bypass its AUG. If it is structured (PV, EV71), most initiation events occur without inspection of dVI, implying that its AUG does not determine ribosomal attachment.
Assuntos
Enterovirus Humano A/fisiologia , Enterovirus Bovino/fisiologia , Iniciação Traducional da Cadeia Peptídica , Poliovirus/fisiologia , Códon de Iniciação/metabolismo , Enterovirus Humano A/genética , Enterovirus Humano A/metabolismo , Enterovirus Bovino/genética , Enterovirus Bovino/metabolismo , Fatores de Iniciação em Eucariotos/metabolismo , Poliovirus/genética , Poliovirus/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Ribossomos/metabolismoRESUMO
BACKGROUND: Bovine enterovirus (BEV) belongs to the species Enterovirus E or F, genus Enterovirus and family Picornaviridae. Although numerous studies have identified BEVs in the feces of cattle with diarrhea, the pathogenicity of BEVs remains unclear. Previously, we reported the detection of novel kobu-like virus in calf feces, by metagenomics analysis. In the present study, we identified a novel BEV in diarrheal feces collected for that survey. Complete genome sequences were determined by deep sequencing in feces. Secondary RNA structure analysis of the 5' untranslated region (UTR), phylogenetic tree construction and pairwise identity analysis were conducted. RESULTS: The complete genome sequences of BEV were genetically distant from other EVs and the VP1 coding region contained novel and unique amino acid sequences. We named this strain as BEV AN12/Bos taurus/JPN/2014 (referred to as BEV-AN12). According to genome analysis, the genome length of this virus is 7414 nucleotides excluding the poly (A) tail and its genome consists of a 5'UTR, open reading frame encoding a single polyprotein, and 3'UTR. The results of secondary RNA structure analysis showed that in the 5'UTR, BEV-AN12 had an additional clover leaf structure and small stem loop structure, similarly to other BEVs. In pairwise identity analysis, BEV-AN12 showed high amino acid (aa) identities to Enterovirus F in the polyprotein, P2 and P3 regions (aa identity ≥82.4%). Therefore, BEV-AN12 is closely related to Enterovirus F. However, aa sequences in the capsid protein regions, particularly the VP1 encoding region, showed significantly low aa identity to other viruses in genus Enterovirus (VP1 aa identity ≤58.6%). In addition, BEV-AN12 branched separately from Enterovirus E and F in phylogenetic trees based on the aa sequences of P1 and VP1, although it clustered with Enterovirus F in trees based on sequences in the P2 and P3 genome region. CONCLUSIONS: We identified novel BEV possessing highly divergent aa sequences in the VP1 coding region in Japan. According to species definition, we proposed naming this strain as "Enterovirus K", which is a novel species within genus Enterovirus. Further genomic studies are needed to understand the pathogenicity of BEVs.
Assuntos
Sequência de Aminoácidos/genética , Proteínas do Capsídeo/genética , Doenças dos Bovinos/virologia , Enterovirus Bovino/genética , Enterovirus Bovino/isolamento & purificação , Regiões 3' não Traduzidas/genética , Regiões 5' não Traduzidas/genética , Animais , Sequência de Bases , Bovinos , Diarreia/veterinária , Infecções por Enterovirus/virologia , Enterovirus Bovino/classificação , Enterovirus Bovino/patogenicidade , Fezes/virologia , Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Japão , Metagenômica/métodos , Fases de Leitura Aberta/genética , Filogenia , RNA Viral/química , RNA Viral/genética , Proteínas Virais/genéticaRESUMO
Turoctocog alfa is a B-domain-truncated recombinant factor VIII protein produced in a Chinese hamster ovary (CHO) cell line. The aim of this study was to evaluate the virus clearance capacity and robustness of the turoctocog alfa purification process. Virus clearance evaluation studies were conducted utilising a scaled-down version of the manufacturing process. Total virus clearance was evaluated using the ecotropic murine leukaemia virus (eMuLV) as a model for non-infectious retrovirus-like particles (RVLPs) and certain enveloped viruses. Other viruses utilised included: infectious bovine rhinotracheitis (IBRV), minute virus of mice (MVM), bovine enterovirus (BEV) and Reo-3 virus (Reo-3). Robust clearance of all model viruses was demonstrated with either new or reused resins. Overall, virus reduction factors were: >18.0 log10 (eMuLV); 11.0 log10 (MVM); >11.8 log10 (Reo-3; >5.0 log10 using nanofiltration); >15.3 log10 (BEV) and >12.7 log10 (IBRV). Taken together, these values demonstrate that the purification process for turoctocog alfa effectively removes a range of enveloped and non-enveloped viruses of different physicochemical properties and sizes.
Assuntos
Enterovirus Bovino , Fator VIII/isolamento & purificação , Herpesvirus Bovino 1 , Vírus da Leucemia Murina , Vírus Miúdo do Camundongo , Inativação de Vírus , Animais , Células CHO , Bovinos , Cricetinae , Cricetulus , Fator VIII/biossíntese , Fator VIII/genética , Camundongos , Proteínas RecombinantesRESUMO
BACKGROUND: Bovine enteroviruses (BEV) are members of the genus Enterovirus in the family Picornaviridae. They are predominantly isolated from cattle feces, but also are detected in feces of other animals, including goats and deer. These viruses are found in apparently healthy animals, as well as in animals with clinical signs and several studies reported recently suggest a potential role of BEV in causing disease in animals. In this study, we surveyed the presence of BEV in domestic and wild animals in Thailand, and assessed their genetic variability. METHODS: Viral RNA was extracted from fecal samples of cattle, domestic goats, Indian bison (gaurs), and deer. The 5' untranslated region (5'UTR) was amplified by nested reverse transcription-polymerase chain reaction (RT-PCR) with primers specific to BEV 5'UTR. PCR products were sequenced and analyzed phylogenetically using the neighbor-joining algorithm to observe genetic variations in regions of the bovine and bovine-like enteroviral 5'UTR found in this study. RESULTS: BEV and BEV-like sequences were detected in the fecal samples of cattle (40/60, 67 %), gaurs (3/30, 10 %), and goats (11/46, 24 %). Phylogenetic analyses of the partial 5'UTR sequences indicated that different BEV variants (both EV-E and EV-F species) co-circulated in the domestic cattle, whereas the sequences from gaurs and goats clustered according to the animal species, suggesting that these viruses are host species-specific. CONCLUSIONS: Varieties of BEV and BEV-like 5'UTR sequences were detected in fecal samples from both domestic and wild animals. To our knowledge, this is the first report of the genetic variability of BEV in Thailand.
Assuntos
Regiões 5' não Traduzidas , Enterovirus Bovino/classificação , Enterovirus Bovino/genética , Variação Genética , Animais , Bison , Bovinos , Enterovirus Bovino/isolamento & purificação , Fezes/virologia , Geografia , Cabras , Filogenia , RNA Viral , Análise de Sequência de DNARESUMO
OBJECTIVES: Enteroviruses (EVs) are the most common cause of aseptic viral meningitis. In some cases, they can cause severe meningoencephalitis and acute flaccid paralysis - an association with some virulent serotypes. The objectives were to describe the epidemiological situation of EV meningitis in children in South Moravia, to elucidate the etiology including the incidence of virulent serotypes and to evaluate the clinical presentation. MATERIAL AND METHODS: A total of 88 children with EV meningitis were prospectively evaluated. In case of aseptic inflammation in the cerebrospinal fluid, EV was detected using real-time PCR. Genotyping was performed in 56 samples using repeated one-step PCR and partial sequencing on a genetic analyzer in the National Reference Laboratory for Enteroviruses in Prague. RESULTS: The patients' age range was 3-17 years; there were more boys than girls. Two epidemics occurred, one involving 17 Roma children and the other involving 8 swimming pool visitors. The most common symptoms were headache, fever and stiff neck. The most frequently (59%) detected agent was Echovirus 30 identified as the cause of the epidemics. In one boy, EV 71 (virulent serotype) was found. The clinical course did not vary from that in other serotypes. All 88 children recovered without complications. CONCLUSIONS: EVs are an important part of the differential diagnosis of neuroinfections, although most infections are benign aseptic meningitis. The clinical presentation did not vary between infections with various serotypes. Higher incidence rates of virulent serotypes were not reported. Echovirus 30 was detected most frequently and was repeatedly identified as the cause of epidemics throughout the Czech Republic.
Assuntos
Infecções por Enterovirus/epidemiologia , Enterovirus Bovino/isolamento & purificação , Meningite Viral/epidemiologia , Meningoencefalite/epidemiologia , Adolescente , Criança , Pré-Escolar , República Tcheca/epidemiologia , Infecções por Enterovirus/diagnóstico , Infecções por Enterovirus/virologia , Feminino , Febre , Humanos , Masculino , Meningite Viral/diagnóstico , Meningite Viral/virologia , Meningoencefalite/diagnóstico , Meningoencefalite/virologia , Reação em Cadeia da Polimerase em Tempo Real , PiscinasRESUMO
A departure from a linear or an exponential intensity decay in the diffracting power of protein crystals as a function of absorbed dose is reported. The observation of a lag phase raises the possibility of collecting significantly more data from crystals held at room temperature before an intolerable intensity decay is reached. A simple model accounting for the form of the intensity decay is reintroduced and is applied for the first time to high frame-rate room-temperature data collection.
Assuntos
Cristalografia por Raios X/métodos , Cristalografia por Raios X/instrumentação , Enterovirus Bovino/química , Vírus da Febre Aftosa/química , Modelos Teóricos , Proteínas/química , TemperaturaRESUMO
Metallic nanoparticles, mainly silver ones, have been widely used as antibacterial agents, and some studies shown they also exert direct antiviral activity against both enveloped and non-enveloped viruses. The objective of this study has been to evaluate the virucidal activity of commercial silver, gold, copper and platinum nanocolloids, recommended by the manufacturer as antimicrobials, against the ECBO virus, according to Polish Standard PN-EN 14675:2006. The highest experimentally observed decrease in the viral load was 0.875 log, which--when contrasted with the reduction in virus titre of at least 4 log expected from disinfectants--indicates that none of the analyzed nanocolloids had a disinfectant power towards the ECBO virus under the conditions defined by the standard.
Assuntos
Antivirais/química , Antivirais/farmacologia , Coloides/farmacologia , Enterovirus Bovino/efeitos dos fármacos , Nanopartículas Metálicas/uso terapêutico , Animais , Linhagem Celular , Coloides/química , Cães , Nanopartículas Metálicas/químicaRESUMO
Bovine enterovirus (BEV) consisting of enterovirus species E (EV-E) and F (EV-F) is the causative agent associated with respiratory and gastrointestinal diseases in cattle. Here, we reported the characterization, genetic diversity, and recombination of novel BEV strains isolated from the major cattle-raising regions in China during 2012-2018. Twenty-seven BEV strains were successfully isolated and characterized. Molecular characterization demonstrated that the majority of these novel BEV strains (24/27) were EV-E, while only few strains (3/27) were EV-F. Sequence analysis revealed the diversity of the circulating BEV strains such as species and subtypes where different species or subtype coinfections were detected in the same regions and even in the same cattle herds. For the EV-E, two novel subtypes, designated as EV-E6 and EV-E7, were revealed in addition to the currently reported EV-E1-EV-E5. Comparative genomic analysis revealed the intraspecies and interspecies genetic exchanges among BEV isolates. The representative strain HeN-B62 was probably from AN12 (EV-F7) and PS-87-Belfast (EV-F3) strains. The interspecies recombination between EV-E and EV-F was also discovered, where the EV-F7-AN12 might be from EV-E5 and EV-F1, and EV-E5-MexKSU/5 may be recombined from EV-F7 and EV-E1. The aforementioned results revealed the genetic diversity and recombination of novel BEV strains and unveiled the different BEV species or subtype infections in the same cattle herd, which will broaden the understanding of enterovirus genetic diversity, recombination, pathogenesis, and prevention of disease outbreaks. IMPORTANCE: Bovine enterovirus (BEV) infection is an emerging disease in China that is characterized by digestive, respiratory, and reproductive disorders. In this study, we first reported two novel EV-E subtypes detected in cattle herds in China, unveiled the coinfection of two enterovirus species (EV-E/EV-F) and different subtypes (EV-E2/EV-E7, EV-E1/EV-E7, and EV-E3/EV-E6) in the same cattle herds, and revealed the enterovirus genetic exchange in intraspecies and interspecies recombination. These results provide an important update of enterovirus prevalence and epidemiological aspects and contribute to a better understanding of enterovirus genetic diversity, evolution, and pathogenesis.
Assuntos
Infecções por Enterovirus , Enterovirus Bovino , Enterovirus , Animais , Bovinos , Enterovirus Bovino/genética , Infecções por Enterovirus/epidemiologia , Infecções por Enterovirus/veterinária , Infecções por Enterovirus/genética , China/epidemiologia , Recombinação Genética , Variação Genética , Filogenia , Genoma ViralRESUMO
Successful cryogenic X-ray structure determination from a single high-pressure-frozen bovine enterovirus 2 crystal is reported. The presented high-pressure-freezing procedure is based on a commercially available device and allows the cryocooling of macromolecular crystals directly in their mother liquor without the time- and crystal-consuming search for optimal cryoconditions. The method is generally applicable and will allow cryogenic data collection from all types of macromolecular crystals.
Assuntos
Enterovirus Bovino/química , Congelamento , Pressão , Animais , Bovinos , Microscopia Crioeletrônica/métodos , Crioprotetores/farmacologia , Cristalização , Cristalografia por Raios X/métodos , Difusão , Enterovirus Bovino/efeitos da radiação , Congelamento/efeitos adversosRESUMO
On the basis of generation of an infectious cDNA clone for the BHM26 strain of bovine enterovirus cluster B (BEV-B), 22 sites on different loops of the BHM26 capsid were selected according to an alignment of its sequence with the structural motifs of BEV-A strain VG-5-27 for insertion of the foot-and-mouth disease virus (FMDV) type O-conserved neutralizing epitope 8E8. Two recombinant viruses, rBEV-A1 and rBEV-DE, in which the FMDV epitope was inserted into the VP1 B-C or D-E loops, were rescued by transfection of BHK-21 cells with the in vitro-transcribed RNA of the recombinant BHM26 genome-length cDNA constructs. The two epitope-inserted viruses were genetically stable and exhibited growth properties similar to those of their parental virus in BHK-21 and IBRS-2 cells, which are susceptible to both BEV and FMDV. However, the two recombinant BEVs (rBEVs) had a significantly lower growth titre than those of the parental virus BHM26 in MDBK and Marc145 cells, which are susceptible to BEV but not to FMDV. These results indicated that insertion of the FMDV epitope into the VP1 B-C or D-E loops of the BEV particle altered the replication properties of BEV. In addition, the two rBEVs were sensitive to neutralization by the FMDV type O-specific mAb 8E8, and anti-FMDV IgG antibodies were induced in mice by intramuscular inoculation with the rBEV-A1 and rBEV-DE viruses. Our results demonstrate that the VP1 B-C and D-E loops of the BEV-B particle can effectively display a foreign epitope, making this an attractive approach for the design of BEV-vectored and epitope-based vaccines.
Assuntos
Anticorpos Neutralizantes/sangue , Proteínas do Capsídeo/metabolismo , Enterovirus Bovino/imunologia , Epitopos/imunologia , Vírus da Febre Aftosa/imunologia , Vetores Genéticos , Animais , Anticorpos Monoclonais/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Bovinos , Linhagem Celular , Enterovirus Bovino/genética , Enterovirus Bovino/metabolismo , Enterovirus Bovino/fisiologia , Vírus da Febre Aftosa/genética , Vírus da Febre Aftosa/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Recombinação Genética , Replicação ViralRESUMO
The Picornaviridae are a large family of small, spherical RNA viruses that includes numerous pathogens. The picornavirus structural proteins VP0, VP1, and VP3 are believed to first form protomers, which then form 14S particles and subsequently assemble to form empty and RNA-filled particles. 14S particles have long been presumed to be pentamers. However, the structure of the 14S particles, their mechanism of assembly, and the role of empty particles during infection are all unknown. We established an in vitro assembly system for bovine enterovirus (BEV) by using purified baculovirus-expressed proteins. By Rayleigh scattering, we determined that 14S particles are 488 kDa, confirming they are pentamers. Image reconstructions based on negative-stain electron microscopy showed that 14S particles have 5-fold symmetry, and their structures correlate extremely well with the corresponding pentamer from crystal structures of mature BEV. Purified 14S particles readily assemble in response to increasing ionic strength or temperature to form 5.8-MDa 12-pentamer particles, indistinguishable from native empty particles. Surprisingly, empty particles were sufficiently stable that, under physiological conditions, dissociation is unlikely to be a biologically relevant reaction. This suggests that empty particles are not a storage form of 14S particles, at least for bovine enterovirus, but are either a dead-end product or direct precursor into which viral RNA is packaged by as-yet-unidentified machinery.
Assuntos
Capsídeo/fisiologia , Enterovirus Bovino/química , Vírion/química , Montagem de Vírus/fisiologia , Baculoviridae , Capsídeo/ultraestrutura , Proteínas do Capsídeo/isolamento & purificação , Proteínas do Capsídeo/metabolismo , Cromatografia Líquida de Alta Pressão , Primers do DNA/genética , Enterovirus Bovino/fisiologia , Técnicas In Vitro , Microscopia Eletrônica de Transmissão , Plasmídeos/genética , Vírion/ultraestruturaRESUMO
AIMS: The virucidal activity of peroxy-products was evaluated and compared with sodium hypochlorite using the EN 14675 European suspension test and a surface test developed in our laboratory. The classical approach on infectivity of viruses was complemented with a prospective approach on virus genomes. METHODS AND RESULTS: Both infectivity tests were adapted and/or developed to determine the activity of disinfectants against reference bovine enterovirus type 1 [enteric cytopathogenic bovine orphan virus (ECBO)] and resistant hepatitis A virus (HAV) in conditions simulating practical use. Similar concentrations of active chlorine were virucidal against both viruses, either at 0·062% using the suspension test or at 0·50-1% using the surface test. However, for potassium monopersulfate and peracetic acid products, concentrations of approximately three times (3%) to 72 times (9%) higher were necessary against HAV than ECBO when determined with the suspension test. With the surface test, 4-8% peroxy-products were virucidal against HAV, either 16 times more peroxy-products concentrations than against ECBO. No significant impact on the targeted area of the viral genome measured by real-time RT-PCRs was obtained for ECBO and HAV suspensions treated with disinfectants, even with doses higher than the minimal virucidal concentrations. CONCLUSIONS: Sodium hypochlorite, but not peroxy-products, had similar activity against ECBO and HAV. No relation could be established between infectivity tests and genome destruction. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first comparative study that investigates with novel suspension and surface tests the reduction of infectivity and genome destruction of two resistant viruses by peroxy-compounds. The results and conclusions collected with European standards are discussed.
Assuntos
Desinfetantes/farmacologia , Enterovirus Bovino/efeitos dos fármacos , Vírus da Hepatite A/efeitos dos fármacos , Ácido Peracético/farmacologia , Compostos de Potássio/farmacologia , Hipoclorito de Sódio/farmacologia , Sulfatos/farmacologia , Animais , Bovinos , Linhagem Celular , Genoma ViralRESUMO
A significant increase in the lifetime of room-temperature macromolecular crystals is reported through the use of a high-brilliance X-ray beam, reduced exposure times and a fast-readout detector. This is attributed to the ability to collect diffraction data before hydroxyl radicals can propagate through the crystal, fatally disrupting the lattice. Hydroxyl radicals are shown to be trapped in amorphous solutions at 100â K. The trend in crystal lifetime was observed in crystals of a soluble protein (immunoglobulin γ Fc receptor IIIa), a virus (bovine enterovirus serotype 2) and a membrane protein (human A(2A) adenosine G-protein coupled receptor). The observation of a similar effect in all three systems provides clear evidence for a common optimal strategy for room-temperature data collection and will inform the design of future synchrotron beamlines and detectors for macromolecular crystallography.