scholarly journals Virus and virus-like diseases of grapevine in Hungary

2011 ◽  
Vol 17 (3) ◽  
Author(s):  
J. Lázár ◽  
Gy. D. Bisztray
Keyword(s):  
Energy Metabolism ◽  
Host Cell ◽  
Particle Morphology ◽  
Plant Viruses ◽  
Diagnostic Methods ◽  
Economic Damage ◽  
Mixed Infections ◽  
Disease Symptoms ◽  
The World

Viruses and viroids are submicroscopic infectious particles which can cause disease symptoms on grapevine. These parasites are depending completely on the energy metabolism of the plant cell. To enter the host cell plant viruses depend on injuries or on transmission via invertebrates (insects, nematodes, etc.). Viruses are classified by many characters including particle morphology, host range and information content of the genome. At present about 70 viruses including 7 viroids infecting grapevine are known. In single or mixed infections they are potentially detrimental to the quality and quantity of grape production in any growing area of the world. Some viruses can cause severe economic damage in vineyards. In Hungary many important viruses and viroids have been detected in grape. This review summarises characteristics of viruses and the results of detection and characterization of virus and virus like diseases of grapevine in Hungary. The identification of the causal agent, its transmission, geographical distribution and the development of the diagnostic methods are also discussed.

scholarly journals Characterization of Glycoproteins from Insect-Specific Goutanap and Negev Viruses

Proceedings ◽  
2020 ◽  
Vol 50 (1) ◽  
pp. 145
Author(s):  
Kathakali Das ◽  
Miri Stolovich-Rain ◽  
Leora Gidon ◽  
Sujata Kumari ◽  
Tomer Schlosser ◽  
...  
Keyword(s):  
Host Cell ◽  
Cell Biology ◽  
Gel Filtration ◽  
Plant Viruses ◽  
Dependent Manner ◽  
Membrane Glycoproteins ◽  
Mosquito Cells ◽  
Blood Sucking ◽  
Virus Interaction

Negeviruses (NVs) are a recently discovered taxon of enveloped, positive sense, single-stranded RNA viruses, infecting blood-sucking insects. While classical arthropod-borne (arbo)viruses like dengue and Chikungunya infect both insects and vertebrates, NVs are restricted to insects and do not have any known vertebrate host and are thus classified as insect-restricted viruses. Previous works have predicted a structure consisting of three ORFs, the first with homologous regions to RNA-dependent RNA polymerase, helicase, and methyl transferases in plant viruses. On the contrary, ORF2 and ORF3 do not have homologs and are predicted to encode membrane glycoproteins. Their structures, functions, and significance remain vague. We focus on the characterization of the viral proteins, structural organization of the virion, and the principles of their interaction with the host cell. We purified the virion particles of Negev virus produced in mosquito cells and identified its structural components. In addition, we cloned and overexpressed ORF2 and ORF3 of Negeviruses. Furthermore, we defined and successfully produced and purified recombinant ORF2. Subsequent characterization using gel filtration, ion exchange, and MALS techniques revealed that the ORF2 of Negeviruses exhibit different higher order assembly patterns: dimerization and multimerization in a concentration- and pH-dependent manner that correspond to their biological role. We combine biochemical, structural and cell biology techniques to unravel mechanisms of Negev virus interaction with the host cell.

scholarly journals Current Advances in Immunological Studies on the Vespidae Venom Antigen 5: Therapeutic and Prophylaxis to Hypersensitivity Responses

Toxins ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 305 ◽  
Author(s):  
Murilo Bazon ◽  
Lais Silveira ◽  
Patricia Simioni ◽  
Márcia Brochetto-Braga
Keyword(s):  
Therapeutic Potential ◽  
Diagnostic Methods ◽  
World Population ◽  
Immediate Hypersensitivity ◽  
Systemic Reactions ◽  
And Topology ◽  
The World ◽  
Allergenic Proteins ◽  
Antigen 5

Although systemic reactions caused by allergenic proteins present in venoms affect a small part of the world population, Hymenoptera stings are among the main causes of immediate hypersensitivity responses, with risk of anaphylactic shock. In the attempt to obtain therapeutic treatments and prophylaxis to hypersensitivity responses, interest in the molecular characterization of these allergens has grown in the scientific community due to the promising results obtained in immunological and clinical studies. The present review provides an update on the knowledge regarding the immune response and the therapeutic potential of Antigen 5 derived from Hymenoptera venom. The results confirm that the identification and topology of epitopes, associated with molecular regions that interact with antibodies, are crucial to the improvement of hypersensitivity diagnostic methods.

scholarly journals Characterization of bronze leaf disease in western Canadian aspen and poplar trees

2021 ◽  
Author(s):  
Champa Wijekoon ◽  
Melanie Kalischuk ◽  
Paige Brunelle ◽  
Ronald J. Howard ◽  
Lawrence M. Kawchuk
Keyword(s):  
Dna Sequences ◽  
Infected Plant ◽  
Morphological Characteristics ◽  
Biological Data ◽  
Diagnostic Methods ◽  
Disease Symptoms ◽  
Leaf Disease ◽  
Poplar Trees ◽  
The Relationship

Aspen and poplar trees are important horticultural plants grown in Canada for aesthetic, commercial woodlot and windbreak applications. Bronze leaf is a destructive disease in <i>Populus </i>spp. and is caused by the fungal pathogen <i>Apioplagiostoma populi </i>Barr. This pathogen is often difficult to isolate and confirm from infected plant tissues and has been mainly identified by disease symptoms and morphological characteristics of <i>A. populi</i> when fruiting bodies form on infected leaves or branches. Affected leaves and branches typically become necrotic and bronze in colour. Air-borne spores and nursery shipments containing infected plants play an important role in the efficient movement of the pathogen. In this study, bronze leaf disease samples from symptomatic trees in Canada were examined microscopically for <i>A. populi</i> perithecia and asci. Pathogen-specific genomic sequences were identified for the development of sensitive stringent diagnostics that indicated branches and petioles were the most effective tissues for detecting <i>A. populi</i>. Leaf samples from symptomatic trees were collected in Canada and examined for perithecia to microscopically characterize <i>A. populi</i> asci and ascospores. Disease associated DNA sequences of the internal transcribed spacer (ITS) 5.8S region of the nuclear ribosomal were isolated from perithecia and symptomatic tree samples. Morphological and molecular biological data from this study characterized the relationship and epidemiology of <i>A. populi</i> and enabled the development of rapid diagnostic methods that restrict the extent of further losses in amenity and commercial plantings of aspen and poplar.

scholarly journals Cloning and Characterization of the Antigenic Membrane Protein (Amp) Gene and In Situ Detection of Amp from Malformed Flowers Infected with Japanese Hydrangea Phyllody Phytoplasma

2008 ◽  
Vol 98 (7) ◽  
pp. 769-775 ◽  
Author(s):  
R. Arashida ◽  
S. Kakizawa ◽  
Y. Ishii ◽  
A. Hoshi ◽  
H.-Y. Jung ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Membrane Protein ◽  
Detectable Level ◽  
Economic Damage ◽  
Disease Symptoms ◽  
Escherichia Coli Cells ◽  
In Situ Detection ◽  
High Diversity

A Japanese hydrangea phyllody (JHP) disease found throughout Japan causes economic damage to the horticultural industry. JHP phytoplasma-infected Japanese hydrangea plants show several disease symptoms involved in floral malformations, such as virescence, phyllody and proliferation. Here, we cloned and characterized the antigenic membrane protein (Amp) gene homolog from the JHP phytoplasma (JHP-amp), expressed the JHP-Amp protein in Escherichia coli cells, and then obtained an antibody against JHP-Amp. The antibody against JHP-Amp had no cross-reactions with the antibody against the Amp protein from a closely related onion yellows phytoplasma. This serologic specificity is probably due to the high diversity of the hydrophilic domains in the Amp proteins. The in situ detection of the JHP-Amp protein revealed that the JHP phytoplasma was localized to the phloem tissues in the malformed flower. This study shows that the JHP-Amp protein is indeed a membrane protein, which is expressed at detectable level in the JHP phytoplasma-infected hydrangea.

Cryomicroscopy of multiphase latices

1991 ◽  
Vol 49 ◽  
pp. 1060-1061
Author(s):  
O. L. Shaffer ◽  
M.S. El-Aasser ◽  
C. L. Zhao ◽  
M. A. Winnik ◽  
R. R. Shivers
Keyword(s):  
Electron Microscopy ◽  
Radiation Damage ◽  
Freeze Fracture ◽  
Particle Morphology ◽  
Second Stage ◽  
Transmission Electron ◽  
Important Approach ◽  
Carbon Coated ◽  
Preparation Techniques

Transmission electron microscopy is an important approach to the characterization of the morphology of multiphase latices. Various sample preparation techniques have been applied to multiphase latices such as OsO4, RuO4 and CsOH stains to distinguish the polymer phases or domains. Radiation damage by an electron beam of latices imbedded in ice has also been used as a technique to study particle morphology. Further studies have been developed in the use of freeze-fracture and the effect of differential radiation damage at liquid nitrogen temperatures of the latex particles embedded in ice and not embedded.Two different series of two-stage latices were prepared with (1) a poly(methyl methacrylate) (PMMA) seed and poly(styrene) (PS) second stage; (2) a PS seed and PMMA second stage. Both series have varying amounts of second-stage monomer which was added to the seed latex semicontinuously. A drop of diluted latex was placed on a 200-mesh Formvar-carbon coated copper grid.

Invasive Shot Hole Borers Euwallacea fornicatus, E. kuroshio, and E. perbrevis (Coleoptera: Curculionidae: Scolytinae)

EDIS ◽  
2020 ◽  
Vol 2020 (1) ◽  
pp. 7
Author(s):  
Demian F. Gomez ◽  
Jiri Hulcr ◽  
Daniel Carrillo
Keyword(s):  
South Africa ◽  
Invasive Species ◽  
Prevention And Control ◽  
Economic Impacts ◽  
Forest Resources ◽  
Economic Damage ◽  
Ambrosia Beetles ◽  
Invasive Insects ◽  
The World ◽  
And Control

Invasive species, those that are nonnative and cause economic damage, are one of the main threats to ecosystems around the world. Ambrosia beetles are some of the most common invasive insects. Currently, severe economic impacts have been increasingly reported for all the invasive shot hole borers in South Africa, California, Israel, and throughout Asia. This 7-page fact sheet written by Demian F. Gomez, Jiri Hulcr, and Daniel Carrillo and published by the School of Forest Resources and Conservation describes shot hole borers and their biology and hosts and lists some strategies for prevention and control of these pests. http://edis.ifas.ufl.edu/fr422

scholarly journals The absence of the caffeine synthase gene is involved in the naturally decaffeinated status of Coffea humblotiana, a wild species from Comoro archipelago

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nathalie Raharimalala ◽  
Stephane Rombauts ◽  
Andrew McCarthy ◽  
Andréa Garavito ◽  
Simon Orozco-Arias ◽  
...  
Keyword(s):  
Wild Species ◽  
Illegitimate Recombination ◽  
Recombination Mechanism ◽  
Comparative Analyses ◽  
Robusta Coffee ◽  
Caffeine Synthase ◽  
The World ◽  
Decaffeinated Coffee ◽  
Chromosome Level

AbstractCaffeine is the most consumed alkaloid stimulant in the world. It is synthesized through the activity of three known N-methyltransferase proteins. Here we are reporting on the 422-Mb chromosome-level assembly of the Coffea humblotiana genome, a wild and endangered, naturally caffeine-free, species from the Comoro archipelago. We predicted 32,874 genes and anchored 88.7% of the sequence onto the 11 chromosomes. Comparative analyses with the African Robusta coffee genome (C. canephora) revealed an extensive genome conservation, despite an estimated 11 million years of divergence and a broad diversity of genome sizes within the Coffea genus. In this genome, the absence of caffeine is likely due to the absence of the caffeine synthase gene which converts theobromine into caffeine through an illegitimate recombination mechanism. These findings pave the way for further characterization of caffeine-free species in the Coffea genus and will guide research towards naturally-decaffeinated coffee drinks for consumers.

Characterization of trypanosome isolates from cattle in Uganda using species-specific DNA probes reveals predominance of mixed infections

1990 ◽  
Vol 11 (03) ◽  
pp. 271-280
Author(s):  
J. H. P. Nyeko ◽  
O. K. Ole-Moiyoi ◽  
P. A. O. Majiwa ◽  
L. H. Otieno ◽  
P. M. Ociba
Keyword(s):  
Dna Probes ◽  
Mixed Infections ◽  
Species Specific

scholarly journals Theoretical and Empirical Characterization of Water as a Factor: Examples and Related Issues with the World Trade Model

Water ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 459
Author(s):  
Ignacio Cazcarro ◽  
Albert E. Steenge
Keyword(s):  
World Trade ◽  
Low Cost ◽  
Virtual Water ◽  
Considerable Change ◽  
Water Research ◽  
Trade Model ◽  
The World ◽  
Main Model ◽  
Selection Of

This article originates from the theoretical and empirical characterization of factors in the World Trade Model (WTM). It first illustrates the usefulness of this type of model for water research to address policy questions related to virtual water trade, water constraints and water scarcity. It also illustrates the importance of certain key decisions regarding the heterogeneity of water and its relation to the technologies being employed and the prices obtained. With regard to WTM, the global economic input–output model in which multiple technologies can produce a “homogeneous output”, it was recently shown that two different mechanisms should be distinguished by which multiple technologies can arise, i.e., from “technology-specific” or from “shared” factors, which implies a mechanism-specific set of prices, quantities and rents. We discuss and extend these characterizations, notably in relation to the real-world characterization of water as a factor (for which we use the terms technology specific, fully shared and “mixed”). We propose that the presence of these separate mechanisms results in the models being sensitive to relatively small variations in specific numerical values. To address this sensitivity, we suggest a specific role for specific (sub)models or key choices to counter unrealistic model outcomes. To support our proposal we present a selection of simulations for aggregated world regions, and show how key results concerning quantities, prices and rents can be subject to considerable change depending on the precise definitions of resource endowments and the technology-specificity of the factors. For instance, depending on the adopted water heterogeneity level, outcomes can vary from relatively low-cost solutions to higher cost ones and can even reach infeasibility. In the main model discussed here (WTM) factor prices are exogenous, which also contributes to the overall numerical sensitivity of the model. All this affects to a large extent our interpretation of the water challenges, which preferably need to be assessed in integrated frameworks, to account for the main socioeconomic variables, technologies and resources.

scholarly journals Modelling Degradation and Replication Kinetics of the Zika Virus In Vitro Infection

Viruses ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 547
Author(s):  
Veronika Bernhauerová ◽  
Veronica V. Rezelj ◽  
Marco Vignuzzi
Keyword(s):  
Mathematical Model ◽  
Viral Infection ◽  
Host Cell ◽  
Decay Time ◽  
Zika Virus ◽  
Infectious Virus ◽  
Numerical Characterization ◽  
The Mathematical Model

Mathematical models of in vitro viral kinetics help us understand and quantify the main determinants underlying the virus–host cell interactions. We aimed to provide a numerical characterization of the Zika virus (ZIKV) in vitro infection kinetics, an arthropod-borne emerging virus that has gained public recognition due to its association with microcephaly in newborns. The mathematical model of in vitro viral infection typically assumes that degradation of extracellular infectious virus proceeds in an exponential manner, that is, each viral particle has the same probability of losing infectivity at any given time. We incubated ZIKV stock in the cell culture media and sampled with high frequency for quantification over the course of 96 h. The data showed a delay in the virus degradation in the first 24 h followed by a decline, which could not be captured by the model with exponentially distributed decay time of infectious virus. Thus, we proposed a model, in which inactivation of infectious ZIKV is gamma distributed and fit the model to the temporal measurements of infectious virus remaining in the media. The model was able to reproduce the data well and yielded the decay time of infectious ZIKV to be 40 h. We studied the in vitro ZIKV infection kinetics by conducting cell infection at two distinct multiplicity of infection and measuring viral loads over time. We fit the mathematical model of in vitro viral infection with gamma distributed degradation time of infectious virus to the viral growth data and identified the timespans and rates involved within the ZIKV-host cell interplay. Our mathematical analysis combined with the data provides a well-described example of non-exponential viral decay dynamics and presents numerical characterization of in vitro infection with ZIKV.

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