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Amino acid sequence and structural properties of protein p12, an African swine fever virus attachment protein. 下载免费PDF全文
A Alcamí A Angulo C Lpez-Otín M Muoz J M Freije A L Carrascosa E Viuela 《Journal of virology》1992,66(6):3860-3868
The gene encoding the African swine fever virus protein p12, which is involved in virus attachment to the host cell, has been mapped and sequenced in the genome of the Vero-adapted virus strain BA71V. The determination of the N-terminal amino acid sequence and the hybridization of oligonucleotide probes derived from this sequence to cloned restriction fragments allowed the mapping of the gene in fragment EcoRI-O, located in the central region of the viral genome. The DNA sequence of an EcoRI-XbaI fragment showed an open reading frame which is predicted to encode a polypeptide of 61 amino acids. The expression of this open reading frame in rabbit reticulocyte lysates and in Escherichia coli gave rise to a 12-kDa polypeptide that was immunoprecipitated with a monoclonal antibody specific for protein p12. The hydrophilicity profile indicated the existence of a stretch of 22 hydrophobic residues in the central part that may anchor the protein in the virus envelope. Three forms of the protein with apparent molecular masses of 17, 12, and 10 kDa in sodium dodecyl sulfate-polyacrylamide gel electrophoresis have been observed, depending on the presence of 2-mercaptoethanol and alkylation with 4-vinylpyridine, indicating that disulfide bonds are responsible for the multimerization of the protein. This result was in agreement with the existence of a cysteine-rich domain in the C-terminal region of the predicted amino acid sequence. The protein was synthesized at late times of infection, and no posttranslational modifications such as glycosylation, phosphorylation, or fatty acid acylation were detected. 相似文献
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A C Hill A A Polak-Vogelzang A F Angulo 《International journal of systematic bacteriology》1992,42(4):513-517
Acholeplasma strains were isolated from the nasopharynx of a horse (strain PN525T [T = type strain]) and the feces of a rabbit (strain B1). One clone of strain PN525T and one clone of strain B1 were examined in detail. These clones were indistinguishable from each other and were serologically distinct from the previously described Acholeplasma and Mycoplasma spp. The strains had the following properties: guanine-plus-cytosine content of 31 mol%; sterol was not required for growth, which occurred under both aerobic and anaerobic conditions; glucose was metabolized; and arginine was hydrolyzed. Strain PN525 (= NCTC 11723) is the type strain of a new species, Acholeplasma multilocale. 相似文献
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In this communication we calculate the probability of discovering a simple epidemic in a large population before the epidemic has reached a given level of prevalence, by regularly taking a small random sample from the population for microbiological screening. Apart from the general formula which has to be evaluated numerically, we derive various simple approximation formulae which shed light on the properties of various monitoring regimes. These formulae are, moreover, rather robust against deviations from the model specifications. The results are applied to the evaluation of the efficiency of an infection-monitoring program in an animal breeding centre. 相似文献
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P. Beer-Romero G. Rodríguez-Ochoa R. Angulo S. Cabrera L. Yarzábal 《Mycopathologia》1989,105(1):19-23
Six cases of sporotrichosis from the Orinoco river basin of Venezuela and Colombia are described; two are of the localized cutaneous type and four are lymphocutaneous. Diagnosis was based on the patient's clinical history and mycological culture. Epidemiology and distinctive cultural habits of the patients are discussed in connection with disease etiology.Abbreviations CAICET
Amazonas Center for Investigation and Control of Tropical Diseases
- TFA
Amazonas Federal Territory 相似文献
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Dánae Cabrera-Toledo Jorge González-Astorga Andrew P. Vovides Alejandro Casas Ofelia Vargas-Ponce Pablo Carrillo-Reyes Janet Nolasco-Soto Ernesto Vega 《Population Ecology》2019,61(1):62-73
Ecological and microevolutionary perspectives were used to investigate signs of background extinction in two endemic species. We studied relict populations of the cycad Dioon caputoi, contrasting its population structure and neighborhood size with those of Dioon planifolium as a demographically healthier reference population. Population dynamics analysis was performed on two populations of D. caputoi through Integral Projection Models and genetic neighborhoods compared between species through 172 Inter Simple Sequence Repeat loci performed in one population of each of the two study species. The D. caputoi populations mostly comprised adult plants, while D. planifolium presented mainly juvenile individuals. Dioon caputoi showed equilibrium in population growth (i.e., λ ≈ 1), with low recruitment, and its genetic neighborhood revealed highly related individuals in a unique distance class (rij = 0.407, 33 m). A contrasting pattern was found in D. planifolium, which showed higher relatedness in the first distance class (rij = 0.543, 5 m), gradually decreasing to 20 m. The discrepancies between the two species reflect different strategies of persistence. Dioon caputoi conserves a relict dynamics with signs of a multigenerational, attritional loss of reproductive fitness, while D. planifolium does not. This study furthers our understanding of the background extinction process and the information will thus contribute to the management and conservation of this endangered species. 相似文献
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Gisela M. Via do Pico Yanina J. Prez María B. Angulo Massimiliano Dematteis 《植物分类学报:英文版》2019,57(5):451-467
Understanding speciation and biodiversity patterns in plants requires knowledge of the general role of climate in allowing polyploids to escape competition and persist with their diploid progenitors. This is a particularly interesting issue in widespread species that present multiple ploidy levels and occur across a heterogeneous environment. Chrysolaena (Vernonieae, Asteraceae) is a cytogenetically very diverse genus, with significant interspecific and intraspecific ploidy level variation and with continuous distribution across South America. No previous studies have summarized chromosome count data of Chrysolaena or addressed the cytogeography of the genus. Ploidy level of Chrysolaena species was determined by chromosome counting during mitosis and/or meiosis; the geographic distribution of cytotypes was examined and the correlations between the distribution of particular cytotypes and current ecological conditions were evaluated. A total of 43 new chromosome counts and five ploidy levels (2x, 4x, 6x, 7x, 8x) were reported. The chromosome number of C. cordifolia (2n = 7x = 70) and a new cytotype for C. propinqua var. canescens (2n = 4x = 40) are reported for the first time. Three geographic areas with high diversity of cytotypes and species were detected. The results obtained do not suggest a clear distribution pattern that depends on climatic factors for Chrysolaena populations. However, a geographic pattern was identified in the distribution of ploidy levels, with diploid species presenting a more restricted distribution than polyploid species. 相似文献
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Paul R. Torgerson Brecht Devleesschauwer Nicolas Praet Niko Speybroeck Arve Lee Willingham Fumiko Kasuga Mohammad B. Rokni Xiao-Nong Zhou Eric M. Fèvre Banchob Sripa Neyla Gargouri Thomas Fürst Christine M. Budke Hélène Carabin Martyn D. Kirk Frederick J. Angulo Arie Havelaar Nilanthi de Silva 《PLoS medicine》2015,12(12)