RESUMO
This study shows the thermo-stability of lyophilized and purified recombinant VP7 bluetongue virus (BTV) protein in the presence of two sugar stabilizers (trehalose and mannitol) at different temperature. Truncated VP7 protein purified by nickel affinity column was lyophilized in the presence of trehalose and mannitol at 60 mM final concentration and then exposed to different temperature like 4, 25, 37 and 45 °C for various periods like 5 months, 7 weeks, 7 days and 48 h, respectively. After thermal treatment, the reactivity of the protein was evaluated in indirect ELISA. At 4 and 25 °C, the protein was stable up to 5 months and 7 weeks, respectively, irrespective of stabilizers used. At 37 °C, it was stable up to 3 days with both the stabilizers, after which it lost its stability and reactivity. At 45 °C, the protein was stable up to 30 and 24 h with trehalose and mannitol stabilizers, respectively. Both stabilizers found suitable for stability of the protein. However, trehalose appeared to have better stabilizing effect, particularly at higher temperatures than the mannitol. Trehalose could be used as stabilizer for freeze-drying the recombinant VP7 protein if an indirect ELISA kit based on the purified rVP7 protein is supplied to different laboratories of the country for detection of BTV antibody in sheep.
RESUMO
The fusion gene (ORF 117) sequences of twelve (n = 12) capripox virus isolates namely sheeppox (SPPV) and goatpox (GTPV) viruses from India were demonstrated for their genetic and phylogenetic relationship among them. All the isolates were confirmed for their identity by routine PCR before targeting ORF 117 gene for sequence analysis. The designed primers specifically amplified ORF 117 gene as 447 bp fragment from total genomic DNA extracted from all the isolates. Sequence analysis revealed a significant percentage of identity among GTPV, SPPV and between them at both nucleotide and amino acid levels. The topology of the phylogenetic tree revealed that three distinct clusters corresponding to SPPV, GTPV and lumpy skin disease virus was formed. However, SPPV Pune/08 and SPPV Roumanian Fanar isolates were clustered into GTPV group as these two isolates showed a 100 and 99.3 % identity with GTPV isolates of India at nt and aa levels, respectively. Protein secondary structure and 3D view was predicted and found that it has high antigenic index and surface probability with low hydrophobicity, and it can be targeted for expression and its evaluation to explore its diagnostic potential in epidemiological investigation in future.
Assuntos
Capripoxvirus/genética , Doenças dos Bovinos/virologia , Doenças das Cabras/virologia , Infecções por Poxviridae/veterinária , Doenças dos Ovinos/virologia , Vaccinia virus/genética , Proteínas Virais de Fusão/genética , Animais , Capripoxvirus/química , Capripoxvirus/classificação , Bovinos , Variação Genética , Cabras , Índia , Dados de Sequência Molecular , Filogenia , Infecções por Poxviridae/virologia , Homologia de Sequência de Aminoácidos , Ovinos , Vaccinia virus/química , Proteínas Virais de Fusão/químicaRESUMO
Newcastle disease virus (NDV) is an avian virus that has not been isolated from naturally infected non-avian and non-human hosts except for one report in which it was isolated from cattle in 1952. We report here for the first time the isolation and identification of NDV from sheep and suggest that this virus be included in the screening of viruses from non-avian hosts.
