RESUMEN
Bartonella species represent important causative agents of blood culture-negative infective endocarditis (IE). Their diagnosis represents a challenge for microbiologists and often relies on serological and molecular tools. However, even if the sensitivity of blood culture remains low, it should not be definitely ruled out. Indeed, we report the unusual case of a 22 year-old Guinean homeless man diagnosed with an IE due to Bartonella quintana. Unexpectedly, conventional blood cultures were positive after 13 days of incubation. Subculture was obtained on blood and chocolate agar, after 15 days of incubation in a 5 % CO2 atmosphere. Bacterial identification was obtained up to the species level using molecular tools (16S rRNA gene amplification and sequencing). A literature review of B. quintana blood culture-positive IE was conducted and revealed eighteen similar reported cases on a 25-year period. This case illustrates that, despite low sensitivity, Bartonella IE may be diagnosed thanks to prolonged blood culture.
RESUMEN
Genetic differences between strains of a baculovirus are often limited to some restriction sites, short DNA deletions or absence of some nonessential genes. The recently coined bro gene family, represents a new major source of intraspecific variability. A comparison between two bro gene sets of Bombyx mori nucleopolyhedroviruses (NPV) shows that bro genes are distributed in three regions for the -T3 and -SC7 virus strains. In BmNPV T3, five bro genes are distributed in three genome locations, whereas the BmNPV SC7 strain possess a single bro copy in each region. In addition, each of the BmNPV SC7 bro genes belongs to one of the three subfamilies present in BmNPV T3. Analysis of bro copy sequences and of adjacent sequences suggests an active redistribution of sequences due to intraspecific recombination. The maintenance of one allele of each subfamily suggests that they play different roles in the viral cycle, and that they are essential.
Asunto(s)
Bombyx/virología , Genes Virales , Nucleopoliedrovirus/genética , Proteínas Virales/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Bombyx/citología , Línea Celular , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Mapeo Restrictivo , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Proteínas Virales/químicaRESUMEN
The nucleotide sequence of two cloned restriction fragments encompassing the granulin genes from the granuloviruses of the potato tuber moth, Phthorimaea operculella, PhopGV, and the Egyptian cotton leaf worm, Spodoptera littoralis, SpliGV, have been determined. Although both viruses are able to infect the same Ph. operculella cell line, their granulins do not cluster in the same phylogenetic branches. PhopGV ganulin is closely related to Cydia pomonella GV (CpGV) and Cryptophlebia leucotreta GV (ClGV) (95.2 and 94% identity at the aminoacid level), while SpliGV granulin falls close to Trichoplusia ni GV and Xestia c-nigrum GV (91.6 and 92.0% respectively). The gene organization around the granulins reflects this clustering. Upstream the PhopGV granulin, an ORF belonging to the ME53 gene family (as ORF 124R of CpGV and 909 of ClGV) is present, while no equivalent ORF is found in this region in SpliGV. Downstream the granulin, both viruses present a gene homologous to the Autographa californica nucleopolyhedrovirus (AcMNPV) ORF 9 followed by a Protein Kinase (AcMNPV ORF10). The structure of this region seems thus conserved not only among nucleopolyhedroviruses but also in at least some granuloviruses.
Asunto(s)
Baculoviridae/genética , Proteínas Virales/genética , Animales , Baculoviridae/clasificación , Secuencia de Bases , Codón de Terminación , ADN Viral , Genes Virales , Datos de Secuencia Molecular , Mariposas Nocturnas/virología , Proteínas de la Matriz de Cuerpos de Oclusión , Sistemas de Lectura Abierta , Regiones Promotoras Genéticas , Homología de Secuencia de Ácido Nucleico , Spodoptera/virologíaRESUMEN
The coding sequences of four overlapping polypeptides starting at four different in-frame AUG codons and co-terminating at the stop codon of the cap gene of Junonia coenia densovirus (JcDNV) were inserted under the control of the p10 promoter of Autographa californica nucleopolyhedrovirus (AcMNPV) to generate AcMNPV-VP1 (four polypeptides), AcMNPV-VP2 (three polypeptides), AcMNPV-VP3 (two polypeptides), and AcMNPV-VP4 (one polypeptide) recombinant viruses. In all cases, infection of Spodoptera frugiperda cells (Sf9) by each of the four recombinant viruses resulted in the production of virus-like particles (VLPs) 22-25 nm in diameter. The VLPs produced by the three recombinants AcMNPV-VP2, AcMNPV-VP3 and AcMNPV-VP4 were abundant and contained three, two and one polypeptides, respectively. VP4, the shortest polypeptide, thus appears to be sufficient for assembly of VLPs morphologically similar to those formed with two to four polypeptides. The ratio of VPs did not appear to be critical for assembly of the particles. The polypeptide starting at the first AUG immediately downstream from the p10 promoter was always the most abundantly expressed in infected cells, regardless of the construct. In contrast, plaque-purified AcMNPV-VP1 recombinants were unstable and produced less than one-twentieth of the VLPs produced by the others. All VP transcripts started at the TAAG late motif of the p10 promoter and had a poly(A) tail 14 nt downstream of a poly(A) addition signal located 98 nucleotides downstream of the common stop codon. No significant transcription initiation inside the cap sequence of AcMNPV-VP2, AcMNPV-VP3 and AcMNPV-PV4 was observed.
Asunto(s)
Cápside/metabolismo , Densovirus/fisiología , Ensamble de Virus , Regiones no Traducidas 3' , Regiones no Traducidas 5' , Animales , Secuencia de Bases , Sitios de Unión , Cápside/genética , Cápside/aislamiento & purificación , Proteínas de la Cápside , Línea Celular , Mapeo Cromosómico , Genes Virales , Vectores Genéticos , Genoma Viral , Datos de Secuencia Molecular , Mutagénesis Insercional , Nucleopoliedrovirus , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/aislamiento & purificación , Proteínas Recombinantes de Fusión/metabolismo , Spodoptera/citología , Virión/fisiologíaRESUMEN
Autographa californica nucleopolyhedrovirus (AcMNPV) does not replicate in Bombyx mori cells (Bm5, BmN). We have shown previously that when a short DNA sequence within AcMNPV ORF95, which encodes the viral helicase P143, is replaced with the colinear region of B. mori nucleopolyhedrovirus (BmNPV), AcMNPV gains the ability to replicate in Bm5 cells. To determine the mutational events in the p143 gene required to allow AcMNPV replication in B. mori cells, AcMNPV recombinants produced in Sf9 cells were screened in vivo in B. mori larvae, which are more permissive to baculovirus infection than B. mori cell lines. Eight combinations of mutations were tested and characterization of viral DNA extracted from dead larvae showed that amino acid changes at position 564 and 577 are required to kill B. mori larvae.
Asunto(s)
Bombyx/virología , Genes Virales , Nucleopoliedrovirus/genética , Nucleopoliedrovirus/patogenicidad , Mutación Puntual , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Línea Celular , ADN Helicasas/genética , Cartilla de ADN/genética , ADN Viral/genética , Larva/virología , Datos de Secuencia Molecular , Nucleopoliedrovirus/fisiología , Recombinación Genética , Spodoptera , Transfección , Virulencia/genética , Replicación Viral/genéticaRESUMEN
Autographa californica nucleopolyhedrovirus (AcMNPV) ORF 86, located within the HindIII C fragment, potentially encodes a protein which shares sequence similarity with two T4 bacteriophage gene products, RNA ligase and polynucleotide kinase. This AcMNPV gene has been designated pnk/pnl but has yet to be assigned a function in virus replication. It has been classified as an immediate early virus gene, since the promoter was active in uninfected insect cells and mRNA transcripts were detectable from 4 to 48 h post-infection and in the presence of cycloheximide or aphidicolin in virus-infected cells. The extremities of the transcript have been mapped by primer extension and 3' RACE-PCR to positions -18 from the translational start codon and +15 downstream of the stop codon. The function of pnk/pnl was investigated by producing a recombinant virus (Acdel86lacZ) with the coding region replaced with that of lacZ. This virus replicated normally in Spodoptera frugiperda (Sf 21) cells, indicating that pnk/pnl is not essential for propagation in these cells. Virus protein production in Acdel86lacZ-infected Sf 21 cells also appeared to be unaffected, with normal synthesis of the IE-1, GP64, VP39 and polyhedrin proteins. Shut-down of host protein synthesis was not abolished in recombinant infection. When other baculovirus genomes were examined for the presence of pnk/pnl by restriction enzyme digestion and PCR, a deletion was found in AcMNPV 1.2, Galleria mellonella NPV (GmMNPV) and Bombyx mori NPV (BmNPV), suggesting that in many isolates this gene has either never been acquired or has been lost during genome evolution. This is one of the first baculovirus immediate early genes that appears to be nonessential for virus survival.
Asunto(s)
Genes Inmediatos-Precoces/genética , Genes Virales , Proteínas Inmediatas-Precoces/genética , Secuencia de Aminoácidos , Animales , Baculoviridae/metabolismo , Secuencia de Bases , Células Cultivadas , Regulación de la Expresión Génica , Insectos , Ligasas/genética , Metiltransferasas/metabolismo , Datos de Secuencia Molecular , Proteínas de la Matriz de Cuerpos de Oclusión , Reacción en Cadena de la Polimerasa , Polinucleótido 5'-Hidroxil-Quinasa/genética , Regiones Promotoras Genéticas , Homología de Secuencia de Aminoácido , Spodoptera , Transfección , Proteínas Virales de Fusión/metabolismo , Proteínas Virales/metabolismo , Proteínas Estructurales ViralesRESUMEN
Autographa californica nucleopolyhedrovirus (AcMNPV) lef-4 gene [ORF 90; Ayres et al. (1994) Virology 202, 586-605] is involved in both late and very late gene expression [Passarelli and Miller (1993) Virology 197, 704-714]. The transcriptional properties of this gene have been analyzed. It is transcribed as a single 1.6-kb mRNA and transcripts were first detected 3 h postinfection (pi). The extremities of the transcript have been mapped by primer extension and 3' RACE-PCR to positions -56 from the translation start codon and +96 downstream of the stop codon. A rabbit polyclonal antiserum has been raised against an internal polypeptide of LEF-4. A 55-kDa protein was observed by Western blot analysis from 5 h pi. LEF-4 localizes preferentially in the nucleus of infected cells and is associated with the virogenic stroma.
Asunto(s)
Expresión Génica , Nucleopoliedrovirus/genética , Proteínas Virales/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting , Western Blotting/métodos , Línea Celular , Mapeo Cromosómico , ADN Viral , Microscopía Inmunoelectrónica , Datos de Secuencia Molecular , Mariposas Nocturnas/virología , Nucleopoliedrovirus/metabolismo , Reacción en Cadena de la Polimerasa , ARN Mensajero , ARN Viral , Conejos , Spodoptera/citología , Fracciones Subcelulares/metabolismo , Transcripción Genética , Proteínas Virales/biosíntesis , Proteínas Virales/metabolismoRESUMEN
The interactions of Bombyx mori nucleopolyhedrovirus (BmNPV) with Spodoptera frugiperda cells (Sf9) were investigated. S. frugiperda cells are usually considered nonpermissive for BmNPV. However, in the present study, BmNPV DNA replication was observed and an increasing infectious titre, reaching 10(4) TCID50/ml on B. mori permissive cells by 6 days post-transfection, developed in the supernatant of infected Sf9 cells. Infection of Sf9 cells by BmNPV did not induce a discernible shutoff of cellular protein synthesis and no overt cytopathic effects were observed. These data indicate that the low permissivity of Sf9 cells for BmNPV replication is associated with an inapparent infection.
Asunto(s)
Bombyx/virología , Nucleopoliedrovirus/fisiología , Animales , Antígenos Virales/análisis , Línea Celular , Replicación del ADN , ADN Viral , Nucleopoliedrovirus/genética , Nucleopoliedrovirus/crecimiento & desarrollo , Conejos , Spodoptera/citología , Transfección , Replicación ViralRESUMEN
1286 nt portion of the 3.1 kbp HindIII-K fragment of the Spodoptera littoralis multiple nucleocapsid nuclear polyhedrosis virus (SIMNPV) DNA genome has been sequenced. The sequence contains the polyhedrin gene preceded by a highly-repeated AGATAA-rich sequence. With 249 amino acids, SIMNPV polyhedrin is the longest known polyhedrin.
Asunto(s)
Genes Virales , Nucleopoliedrovirus/genética , Proteínas Virales/genética , Secuencia de Aminoácidos , Animales , Baculoviridae/genética , Secuencia de Bases , Desoxirribonucleasa HindIII , Datos de Secuencia Molecular , Mariposas Nocturnas/microbiología , Proteínas de la Matriz de Cuerpos de Oclusión , Regiones Promotoras Genéticas , Mapeo Restrictivo , Homología de Secuencia de Aminoácido , Proteínas Estructurales ViralesRESUMEN
Recombinant baculoviruses obtained by coinfection of insect cells with Autographa californica and Bombyx mori nuclear polyhedrosis viruses (AcNPV and BmNPV, respectively) possess a wider in vitro host range than either parent virus. To localize the DNA sequences responsible for this species specificity, we used a two-step method of production and selection of recombinant viruses with altered specificity. Sf9 cells, which are permissive for AcNPV, were first cotransfected with genomic AcNPV DNA and a complete or incomplete set of BmNPV restriction fragments. AcNPV-BmNPV recombinants from the Sf9 supernatant were then selected on the basis of ability to replicate in B. mori Bm5 cells, which are not permissive for AcNPV. Cotransfection of AcNPV DNA with the 7.6-kbp BmNPV Sma I-C fragment was sufficient to produce recombinants able to infect both Sf9 and Bm5 cells. A series of cotransfections with subclones of this fragment defined a 79-nt sequence within the p143 helicase gene capable of extending AcNPV host range in vitro. In this 79-nt region, BmNPV and AcNPV differ at six positions, corresponding to four amino acid substitutions. The involvement of the 79-nt region in species specificity control was confirmed by cotransfecting AcNPV DNA and gel-purified polymerase chain reaction products derived from the BmNPV p143 gene. Replacement in the AcNPV genome of three AcNPV-specific amino acids by the three corresponding BmNPV-specific amino acids at positions 556, 564, and 577 of the p143 protein extends AcNPV host range to B. mori larvae.
Asunto(s)
ADN Helicasas/genética , Nucleopoliedrovirus/crecimiento & desarrollo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Línea Celular , Cartilla de ADN/química , ADN Viral/genética , Genes Virales , Larva , Datos de Secuencia Molecular , Mariposas Nocturnas/microbiología , Nucleopoliedrovirus/genética , Mapeo Restrictivo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Especificidad de la Especie , Proteínas Estructurales Virales/genética , Replicación ViralRESUMEN
A physical map for the genome of Spodoptera littoralis (Egyptian cottonworm) nuclear polyhedrosis virus of B-type (S1MNPV-B) [Cherry CL, Summers MD (1985) J Invertebr Pathol 46: 289-295] was prepared using the restriction endonucleases SmaI, SfiI, NotI, ApaI, KpnI, BstEII, PstI, SacI, and HindIII. The size of the genome was estimated to 136 kbp for the Morocco isolate (S1MNPV-M2) and to 135 kbp for the Lyon isolate (S1MNPV-L4). HindIII-K was used as the zero-point of the map because it hybridized to EcoRI-I and BamHI-F fragment of Autographa californica (AcMNPV) DNA, and the direction of transcription of the S1MNPV polyhedrin gene was chosen left to right. Hybridization of six AcMNPV cloned DNA fragments with S1MNPV-B genome shows that S1MNPV-B and AcMNPV genomic structures are not aligned.
Asunto(s)
Genes Virales , Virus de Insectos/genética , Mapeo Restrictivo , ADN Viral/genética , Hibridación de Ácido Nucleico , Homología de Secuencia de Ácido NucleicoAsunto(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 ViralRESUMEN
Sequence studies of the N-terminal halves of the lysozymes isolated from Bombyx mori, Gallera mellonella and Spodoptera littoralis (Lepidoptera) allow us to classify these enzymes among the c (chicken) type lysozymes.
Asunto(s)
Lepidópteros/enzimología , Muramidasa/análisis , Secuencia de Aminoácidos , Animales , Evolución Biológica , Bombyx/enzimología , Pollos , Mariposas Nocturnas/enzimología , Especificidad de la EspecieAsunto(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
Examination of the polyhedron protein by polyacrylamide gel electrophoresis shows only one polypeptide with a molecular weight of 25,500 +/- 500 daltons, while that of virion proteins reveals 13 polypeptides. No antigenic community could be demonstrated between the polyhedron protein of the Baculovirus of T. paludosa and the polyhedron protein of several other Baculoviruses.
Asunto(s)
Virus ADN/análisis , Dípteros/microbiología , Cuerpos de Inclusión Viral , Proteínas Virales/análisis , Animales , Antígenos Virales/análisis , Electroforesis en Gel de Poliacrilamida , Peso Molecular , Proteínas Virales/inmunologíaRESUMEN
The proteinaceous matrix of 23 insect Baculovirus inclusions consists of a single polypeptide of molecular weight varying from 25,100 to 31,360 daltons depending upon the virus and in correlation wwith taxonomic position of the host.
Asunto(s)
Cuerpos de Inclusión Viral , Virus de Insectos/análisis , Proteínas Virales/análisis , Animales , Dípteros/microbiología , Himenópteros/microbiología , Lepidópteros/microbiología , Peso Molecular , Especificidad de la EspecieRESUMEN
On the basis of their buoyant densities in CsCl and their capsid polypeptides, three viruses isolated from Drosophila spp. which were originally described as serotypes, are now classified as distinct viruses. The biochemical properties of each virus suggest that it has several key features in common with the mammalian picornaviruses.
Asunto(s)
Cápside/análisis , Drosophila/microbiología , Virus de Insectos/análisis , Péptidos/análisis , Proteínas Virales/análisis , Centrifugación por Gradiente de Densidad , Virus de Insectos/clasificación , Peso MolecularRESUMEN
Five of six Baculovirus species studied induce cytoplasmic and nuclear fibrous sheets, observed by electron microscopy, within infected cells of lepidopterous. The reticulated structures, revealed by fluorescence microscopy, assimilate the fibrillar substance induced by these viruses thanks to the affinity they show for globulins of healthy rabbits.
Asunto(s)
Virus de Insectos , Lepidópteros/microbiología , Animales , Células Sanguíneas/microbiología , Núcleo Celular/microbiología , Citoplasma/microbiología , Técnica del Anticuerpo Fluorescente , Microscopía ElectrónicaRESUMEN
Induction of filamentous nuclear structures by Baculoviruses are observed in the hemocytes of Galleria mellonella larvae. Modalities of detection of these virus-induced structures by means of sheep or rabbit globulines labelled with fluorescein isothiocyanate are described.