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1.
A manually transmissible virus, for which the name olive latent ringspot virus (OLRV) is proposed, was isolated from a symptomless olive tree. The virus was mechanically transmitted to test plants. Purified preparations of OLRV contained three classes of isometric particle, c. 28 nm in diameter, with sedimentation coefficients of 525 (T), 975 (M) and 1325 (B) and containing 0, 30 and 43% nucleic acid respectively. At equilibrium in CsCl gradients, the buoyant densities of T and M components were 1–29 and 1–43 g/cm3 respectively, whereas B component separated into two sub-components with buoyant densities of 1–51 g/cm3 (BJ and 1–52 g/cm3 (B2). Particle preparations contained two species of single-stranded RNA with mol. wt 1–40 times 106 and 2–65 times 106, both necessary for infectivity. The coat protein of OLRV, dissociated under strong denaturing conditions, separated into four components in polyacrylamide gel electrophoresis. Over 75% of the protein was found in a band with mol. wt 57 600, but all four components were recognised as oligomers of a monomeric form with mol. wt 14 300. OLRV was serologically unrelated to 26 different isometric plant viruses including 17 recognised nepoviruses. Its properties strongly indicate that it is a hitherto undescribed member of the nepovirus group. 相似文献
2.
RNA with amino acid-acceptor activity isolated from an oncogenic virus 总被引:14,自引:0,他引:14
M Trávnícek 《Biochimica et biophysica acta》1968,166(3):757-759
3.
Tommasi S Crapolicchio A Lacalamita R Bruno M Monaco A Petroni S Schittulli F Longo S Digennaro M Calistri D Mangia A Paradiso A 《Mutation research》2005,578(1-2):395-405
INTRODUCTION: Hereditary breast cancer has been partly attributed to germline mutations in the BRCA1 gene that are deleterious for BRCA1 protein activity. This paper analyzes the incidence and characteristics of detectable BRCA1 mutations and polymorphisms in a hospital-based consecutive series of breast cancer patients from southern Italy to investigate the incidence and the association of these molecular alterations with breast cancer biology and family history. METHODS: One hundred cases with familial characteristics were selected from a consecutive series of 511 patients with a first diagnosis of breast cancer. DNA from peripheral blood was screened for whole BRCA1 gene mutations utilizing dHPLC as a pre-screening analysis and automatic DNA sequencing for the identification of specific alterations. RESULTS: In the overall series of 511 patients, 100 had a family history of breast cancer and were investigated for BRCA1 mutations. Two types of BRCA1 mutations were identified, 5382insC in six cases and 4566delA in one case. The 5382insC mutation was present in two out of six cases with ovarian cancer while 4566delA in one case of male cancer. The most frequent missense polymorphisms were E1038G, P871L, K1183R in exon 11, S1613G, M1652I in exon 16 and D1778G in exon 22. Confirming what found in previous studies, patients in whom pathological BRCA1 mutations were detected had early-onset breast cancer (p=0.05), positive nodal status (p=0.05), lower ER (p=0.02) and PgR (p=0.01) content. Interestingly, the K1183R polymorphism and, less strongly, S1613G polymorphism were associated to mutational risk (K1183R: OR 0.1 p=0.03; S1613G: OR 2.7 p=0.08). CONCLUSION: Mutations in the BRCA1 gene are frequent also in our consecutive series of patients from southern Italy. An association between two detected single nucleotide polymorphisms (SNPs) and BRCA1 mutational risk was ascertained. Finally, we confirm the fact that peculiar clinical-pathological features seem to characterize patients with a family history of breast cancer and BRCA1 alterations. 相似文献
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Clara Romano Francesca Mancianti Simona Nardoni Gaetano Ariti Paola Caposciutti Michele Fimiani 《Revista iberoamericana de micología》2013,30(4):231-234
BackgroundPityriasis versicolor (PV) is an infection caused by various species of Malassezia yeast. There is no agreement in the literature concerning the species of Malassezia and the demographic, clinical, and mycological data.AimsTo prospectively identify Malassezia species isolated from lesions of patients with extensive, long standing and recurrent forms of PV and to estimate the relationship between Malassezia species and the demographic and clinical data of the patients.MethodsAll patients with PV were enrolled over a four-year period. Malassezia species were isolated in cultures and identified by morphological features and physiological tests. In the last 2 years a PCR-based technique was used to confirm the species’ identification.ResultsA total of 74 patients (43 males and 31 females, mean age 39.5 years) were enrolled. Only one species was isolated in 45 patients, and more than one species were identified in the remaining 28 patients (38%). M. globosa was the most frequently isolated (60.3%) species. There was a significant association between the isolation of 2 or more species and the presence of at least one predisposing factor. In the last 29 cases, which were subjected to PCR, there were no differences in the identification of isolated species as compared to traditional methods.ConclusionsThe isolation of more than one species in a single lesion is not infrequent in PV and is related to the presence of one predisposing factor. The isolated species isolated were not influenced by demographic and clinical features. The traditional and more recent (PCR) procedures gave the same results in the isolated species. 相似文献
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Maldonado-Barragán A Caballero-Guerrero B Lucena-Padrós H Ruiz-Barba JL 《Journal of bacteriology》2011,193(19):5605
Lactobacillus pentosus is the most prevalent lactic acid bacterium in Spanish-style green olive fermentations. Here we present the draft genome sequence of L. pentosus IG1, a bacteriocin-producing strain with biotechnological and probiotic properties isolated from this food fermentations. 相似文献
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Teresa Zotta Paolo Piraino Eugenio Parente Giovanni Salzano Annamaria Ricciardi 《World journal of microbiology & biotechnology》2008,24(9):1785-1795
A total of 41 strains of lactic acid bacteria (LAB) isolated from durum wheat sourdoughs used to produce Cornetto di Matera bread, were identified by SDS-PAGE of whole cell proteins (WCP) and screened for acid production ability, antimicrobial
activity and exopolysaccharide (EPS) production. The isolates were identified as Lactobacillus plantarum (49%), Leuconostoc mesenteroides (17%), Lactobacillus curvatus (15%), Lactobacillus paraplantarum (12%), Weissella cibaria (5%) and Lactobacillus pentosus (2%). Several strains of Lb. plantarum and Leuc. mesenteroides showed a high acid production ability. The antagonistic activity was tested using an agar-spot deferred antagonism assay
against a set of five indicators. The species had different profiles of inhibition. Lb. plantarum had the largest spectrum of inhibition, while no isolates of W. cibaria and Leuc. mesenteroides showed antimicrobial activity. No strains had antimicrobial activity against Bacillus cereus. The inhibitory activity of five strains was confirmed to be sensitive to proteolytic enzymes and thus potentially due to
bacteriocin production. All Leuc. mesenteroides and W. cibaria strains produced EPS from sucrose. Some Lb. plantarum and Lb. paraplantarum strains produced EPS from different sugars in solid media. EPS production in liquid media was different within the species,
with the highest production in liquid media containing glucose and maltose. A defined strain starter culture (W. cibaria DBPZ1006, Lb. plantarum DBPZ1015 and S. cerevisiae MTG10) was selected on the basis of technological properties and tested in model sourdough fermentations. 相似文献
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Hepatitis C virus RNA synthesis in a cell-free system isolated from replicon-containing hepatoma cells 总被引:3,自引:0,他引:3
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A number of hepatitis C virus (HCV) proteins, including NS5B, the RNA-dependent RNA polymerase, were detected in membrane fractions from Huh7 cells containing autonomously replicating HCV RNA replicons. These membrane fractions were used in a cell-free system for the analysis of HCV RNA replication. Initial characterization revealed a reaction in which the production of replicon RNA increased over time at temperatures ranging from 25 to 40 degrees C. Heparin sensitivity and nucleotide starvation experiments suggested that de novo initiation was occurring in this system. Both Mn2+ and Mg2+ cations could be used in the reaction; however, concentrations of Mn2+ greater than 1 mM were inhibitory. Compounds shown to inhibit recombinant NS3 and NS5B activity in vitro were found to inhibit RNA synthesis in the cell-free system. This system should be useful for biochemical analysis of HCV RNA synthesis by a multisubunit membrane-associated replicase and for evaluating potential antiviral agents identified in biochemical or cell-based screens. 相似文献
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Jiao P Cao L Yuan R Wei L Song Y Shen D Gong L Luo K Ren T Liao M 《Journal of virology》2012,86(14):7716
An H10N8 avian influenza virus (AIV), designated A/Duck/Guangdong/E1/2012 (H10N8), was isolated from a duck in January 2012. This is first report that this subtype of AIV was isolated from a live bird market (LBM) in Guangdong Province in southern China. Furthermore, the complete genome of this strain was analyzed. The availability of genome sequences is helpful to further investigations of epidemiology and molecular characteristics of AIV in southern China. 相似文献
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Human immunodeficiency virus type 1 variants isolated from single plasma samples display a wide spectrum of neutralization sensitivity
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Skrabal K Saragosti S Labernardière JL Barin F Clavel F Mammano F 《Journal of virology》2005,79(18):11848-11857
Individuals infected with human immunodeficiency virus type 1 (HIV-1) harbor a mixture of viral variants with different sequences and in some instances with different phenotypic properties. Major and rapid fluctuations in the proportion of viral variants coexisting in an infected individual can be observed under strong pharmacological and immune selective pressure. Because of the short half-life of HIV-infected cells and of HIV virions in the blood, plasma virus populations are highly relevant to HIV evolution in the face of these selective pressures. Here we analyzed the sensitivity to antibody-mediated neutralization of viral variants coexisting in the plasma virus populations of two infected patients. For each patient, several replication-competent viral clones were constructed that carry primary envelope gene sequences obtained from a single plasma sample. Viral clones differed in their tropism and replicative capacity and in the number and positions of glycosylation sites in the envelope glycoproteins. Viruses were tested against heterologous and autologous sera obtained at different time points. Interestingly, we found that viral variants coexisting in each plasma sample were highly heterogeneous in terms of sensitivity to neutralization. The order of sensitivity depended on the serum used and was not associated with virus tropism. The neutralization potency of sera increased with the duration of the infection for both autologous and heterologous neutralization. 相似文献
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Electron microscopic study of a herpes-type virus isolated from an infant with exanthem subitum 总被引:2,自引:0,他引:2
M Yoshida F Uno Z L Bai M Yamada S Nii T Sata T Kurata K Yamanishi M Takahashi 《Microbiology and immunology》1989,33(2):147-154
Human lymphocytes and MT4 cells infected with a virus isolated from a patient with exanthem subitum were examined by transmission and scanning electron microscopy. The most striking characteristic of the ultrastructure of this herpes-type virus was that nucleocapsids located outside the nucleus were each coated distinctly with a tegument of moderate electron density. Tubular structures formed due to some mistakes in the viral assembly were also detected in the nucleus. Morphological differentiation of this virus from the other human herpesvirus was discussed. From these observations it was concluded that this virus has the same ultrastructural characteristics as HBLV (HHV-6). 相似文献
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Penghui Yang Dongmei Chong Tang Deyan Luo Yueqiang Duan Daxin Peng Xiliang Wang 《Biochemical and biophysical research communications》2010,396(4):973-977
The continued spread of a highly pathogenic avian influenza (HPAI) H5N1 virus among poultry and wild birds has posed a potential threat to human public health. An influenza pandemic happens, when a new subtype that has not previously circulated in humans emerges. Almost all of the influenza pandemics in history have originated from avian influenza viruses (AIV). Birds are significant reservoirs of influenza viruses. In the present study, we performed a survey of avian influenza virus in ostriches and H5N1 virus (A/Ostrich/SuZhou/097/03, China097) was isolated. This H5N1 virus is highly pathogenic to both chickens and mice. It is also able to replicate in the lungs of, and to cause death in, BALB/c mice following intranasal administration. It forms plaques in chicken embryo fibroblast (CEF) cells in the absence of trypsin. The hemagglutinin (HA) gene of the virus is genetically similar to A/Goose/Guangdong/1/96(H5N1) and belongs to clade 0. The HA sequence contains multiple basic amino acids adjacent to the cleavage site, a motif associated with HPAI viruses. More importantly, the existence of H5N1 isolates in ostriches highlights the potential threat of wild bird infections to veterinary and public health. 相似文献
16.
Gonzalez-Dosal R Horan KA Paludan SR 《Biochemical and biophysical research communications》2012,418(4):806-810
Reactive oxygen species (ROS) are crucial secondary messengers of signaling pathways. Redox-dependent signaling events have been previously described in the innate immune response. However, the mechanism by which ROS modulates anti-viral innate immune signaling is not fully clarified. Here, we report that mitochondria-derived ROS differentially regulate the innate response to DNA and RNA viruses (herpes simplex virus (HSV) and Sendai virus (SeV), respectively), with the cytokine response to HSV being negatively regulated by mitochondrial ROS. Importantly, specific activation of Toll-like receptors (TLRs) and DNA receptors (DNARs) but not retinoic acid inducible gene I (RIG-I)-like receptors (RLRs), led to signaling cascades that were inhibited by mitochondrial ROS production. Thus, localized mitochondrial ROS exerts negative modulation of innate immune responses to the DNA virus HSV-2 but not the RNA virus SeV. 相似文献
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Hibiscus latent ringspot virus (HLRV) was prevalent in Hibiscus rosa-sinensis in Ibadan, Nigeria. It was readily transmitted mechanically to 22 of 73 species from seven of 20 families, but was best propagated in Nicotiana clevelandii or Hibiscus cannabinus and assayed in Chenopodium murale. HLRV was readily purified from systemically infected hosts by differential centrifugation of leaf extracts clarified with 8.0% n-butanol, followed by molecular permeation chromatography on controlled-pore glass beads (700 Å, 120–200 mesh). The virus has isometric particles c. 28 nm in diameter which sedimented as three components (T, M and B), with sedimentation coefficients (s°20, w) of 51; 114 and 132 S and buoyant densities in caesium chloride of 1.32, 1.49 and 1.52 g/cm3, respectively. All three components contained a single polypeptide of rnol. wt 53.6 × 103. T component particles contained only protein but M and B components also contained single-stranded RNA of rnol. wt 2.2 × 106 and 2.5 × 106, respectively. The properties of HLRV suggest affinities with nepoviruses but no serological relationship was detected between HLRV and 15 recognised or possible members of the nepovirus group. 相似文献
18.
Caloplaca erodens [sect. Pyrenodesmia], a new lichen species from Italy with an unusual thallus type
Caloplaca erodens is a new species of sect. Pyrenodesmia, characterised by an orbicular, sorediate, bluish-grey thallus which is endolithic but emerges at the periphery with a white,
K−, obscurely lobate prothallus. The species is frequent on calcareous outcrops and walls of isolated churches and ruins of
the Central Apennines (Sibillini, Gran Sasso), where it may occur in large monospecific populations, from 1000 to 2500 m asl.,
and is also known from dry sites of the southern Alps. It has been found with apothecia only in the type locality, being predominantly
sterile. The reproduction of this lichen is evidently linked to the release of fragments of clusters of photobiont cells and
mycobiont hyphae which are continuously exposed with the dissolution of the substratum. Readily distinguished from the apparently
similar endolithic C. alociza (which is characterised by numerous apothecia, black, K+ purple prothallus, and esorediate thallus), C. erodens probably belongs to the C. circumalbata complex, whose taxa are always epilithic but have a white, K− prothallus. The phylogenetic position of the new species within
sect. Pyrenodesmia as inferred by ITS sequences of the nuclear ribosomal DNA is shortly discussed. 相似文献
19.
Blackberry fruits symptomatic for gray mold were collected from three commercial blackberry fields in northwestern South Carolina. Single-spore isolates were generated and two distinct phenotypes were discovered in each location; one sporulated on PDA and one did not. One isolate of each phenotype and location (six isolates total) were selected for in depth molecular and morphological characterization. Glyceraldehyde-3-phosphate dehydrogenase (G3PDH), heat-shock protein 60 (HSP60) and DNA-dependent RNA polymerase subunit II (RPB2) coding sequence alignment revealed Botrytis cinerea as the sporulating phenotype and a new yet undescribed species as the non-sporulating phenotype. The new Botrytis sp., described herein as Botrytis caroliniana, was most closely related genetically to B. fabiopsis and B. galanthina, the causal agents of gray mold disease of broad bean and snowdrop, respectively. It produces smaller conidia than either B. fabiopsis or B. galanthina, and sequence analysis of genes encoding necrosis and ethylene-inducing proteins (NEPs) also indicated that the Botrytis isolates represent a separate and distinct species. The new species is pathogenic on blackberry fruits and broad bean leaves, which distinguishes it further from B. galanthina. The new species formed white to pale gray colonies with short, tufted aerial mycelium and produced black sclerotia on PDA at 20 C. To our knowledge this is only the third Botrytis species discovered to cause disease on blackberry in the United States. 相似文献
20.
Reimundo P Pignatelli M Alcaraz LD D'Auria G Moya A Guijarro JA 《Journal of bacteriology》2011,193(14):3684-3685
Lactococcus garvieae is the etiological agent of lactococcosis disease, affecting many cultured fish species worldwide. In addition, this bacterium is currently considered a potential zoonotic microorganism since it is known to cause several opportunistic human infections. Here we present the draft genome sequence of the L. garvieae strain UNIUD074. 相似文献