RESUMEN
A picornavirus was isolated from various life stages of the Queensland fruit fly, Dacus tryoni. This virus, Queensland fruit fly virus (QFFV) has virions with a diameter of 30 nm and a sedimentation coefficient of 178 S. One third of the particles in preparations were empty capsids or natural top component (NTC) with a sedimentation coefficient of 95 S. The buoyant density (rho) of virions and NTC in CsCl was 1.34 and 1.30 g/ml respectively; small amounts of a dense component (rho = 1.45 g/ml) were also detected. The capsid contained three major protein species of molecular weight (mol.wt.) 41,700, 36,500, and 31,300, in approximately equimolar proportions. NTC contained three major species of mol. wt. 44,700, 41,700, and 31,300. The nucleic acid present only in the bottom component virions was RNA and comprised about 30% of the particle weight and had a mol. wt of 2.88 kd, contained a poly(A) tract, and had a base ratio: G = 20; A = 32; C = 15; U = 33. The mol. wt. of the virion was estimated to be approximately equal to 9.5 kd. When virions were heated at 56 degrees C and above, they converted into artificial top component (ATC), which had the same protein composition as the virion when analysed by SDS-PAGE. In immunodiffusion tests the virions and NTC were indistinguishable, but a minor difference in antigenicity was detected between the virions and ATC. Virions were stable between pH 3 and 9 inclusive, and between 5 and 7 in the presence of 0.14 M NaCl. Immunodiffusion tests showed that QFFV was serologically unrelated to a range of picornaviruses as well as an unclassified virus isolated from the Mediterranean fruit fly, Ceratitis capitata. The data show that QFFV is probably a member of the Picornaviridae, genus Enterovirus.
Asunto(s)
Drosophila/microbiología , Virus de Insectos/clasificación , Picornaviridae/clasificación , Animales , Cápside/análisis , Centrifugación por Gradiente de Densidad , Electroforesis en Gel de Poliacrilamida , Calor , Concentración de Iones de Hidrógeno , Inmunodifusión , Virus de Insectos/análisis , Virus de Insectos/aislamiento & purificación , Virus de Insectos/ultraestructura , Peso Molecular , Picornaviridae/análisis , Picornaviridae/aislamiento & purificación , Picornaviridae/ultraestructura , ARN Viral/análisis , Especificidad de la Especie , Proteínas Virales/análisis , Virión/análisis , Cultivo de VirusRESUMEN
A small RNA virus with a bipartite genome was isolated from Oncopera intricoides. It was named Boolarra virus (BoV). The particle had a diameter of 30 nm, a sedimentation coefficient of 140S, and a buoyant density of 1.34 g/ml in CsCl. The capsid proteins were examined by SDS-PAGE and consisted of a major species of molecular weight (mol. wt.) 38,000 and a minor one of mol. wt. 40,600. The particle contained 21.2% RNA which was divided between a 22S and a 17S species whose mol. wts. were 1.03 x 10(6) and 0.47 x 10(6), respectively. These properties were comparable to those of the Nodaviridae and established BoV as a member of the family. Serologically, BoV shared antigenic determinants with both Nodamura virus and black beetle virus.
Asunto(s)
Virus de Insectos/aislamiento & purificación , Lepidópteros/microbiología , Virus ARN/aislamiento & purificación , Animales , Virus de Insectos/clasificación , Virus de Insectos/ultraestructura , Microscopía Electrónica , Peso Molecular , Virus ARN/clasificación , Virus ARN/ultraestructura , ARN Viral/análisis , Proteínas Virales/análisis , Replicación ViralAsunto(s)
Virus de Insectos/genética , Virus ARN/genética , Antígenos Virales/análisis , Células Cultivadas , Drosophila/microbiología , Ecología , Peso Molecular , Ortópteros/microbiología , Especificidad de la Especie , Proteínas Virales/análisis , Proteínas Virales/inmunología , Virosis/transmisión , Replicación ViralAsunto(s)
Virus de Insectos , Animales , Antígenos/análisis , Drosophila melanogaster/microbiología , Virus de Insectos/inmunología , Virus de Insectos/metabolismo , Ortópteros/microbiología , Picornaviridae/inmunología , Picornaviridae/metabolismo , Proteínas Virales/inmunología , Replicación ViralRESUMEN
Serological tests were done to examine the relationships between twelve picorna-like viruses of insects. The results of the tests indicated that the majority of the viruses are unrelated. However, cricket paralysis virus, isolated from Australian wild field crickets, appeared to be identical to Drosophila C virus, independently isolated in France. Cricket paralysis virus was infective for adults of Drosophila melanogaster and its infectivity towards Galleria melonella was neutralised by Drosophila C virus antiserum. It is therefore concluded that cricket paralysis virus and Drosophila C virus are very closely related if not identical.
Asunto(s)
Virus de Insectos/inmunología , Animales , Antígenos Virales/análisis , Drosophila melanogaster/microbiología , Virus de Insectos/clasificación , Virus de Insectos/patogenicidad , Lepidópteros/microbiología , Virus ARNRESUMEN
Three virus-like particles have been isolated from diseased larvae of Antheraea eucalypti. Serological tests established that one of them was indistinguishable from cricket paralysis virus (CrPV). CrPV isolated from crickets and from Antheraea were cross-infectious, and crickets could acquire lethal doses of the virus by feeding on infected Antheraea larvae. In addition to two species of Teleogryllus, three other species of Orthoptera and nine out of ten species of Lepidoptera tested were susceptible to the virus. It is suggested that CrPV may have originated amongst the Lepidoptera and has been acquired by the field cricket by infectious passage along a food chain.