79 research outputs found

    STUDIES REGARDING THE TRANSMISSION OF POTATO VIRUS Y (PVY) TROUGH SEVERAL MECHANICAL MEANS

    Get PDF
    The aim of this studies was to investigate the transmission of PVY strains PVYo, PVYN, PVYNTN, via tuber cutting and plant treated in susceptible cultivars. For the tuber cutting experiment, after one infected tuber was cut with a knife, four uninfected tubers were cut sequentially with the same instrument without disinfecting it between the cuts. In the other experiments, the virus transmission from infected to healthy plants was made by bouncing, brushing, hammering, squeezing and carborundum rubbing treatments. These treatments allowed exchange of sap between the healthy and infected material. Results revelead that seed cutting did not transmit the pathogen, whereas the other plant treatments caused varying level of PVY transmission, depending on the experiments variant. Plant bouncing was the least effective whereas hammering was the most effective variant

    BENEFICIALTREATMENTS ON PVX AND PVY INFECTED POTATO(SOLANUM TUBEROSUM L.) PLANTS

    Get PDF
    This study presents the efficiency of some combined techniques (chemo- and electrotherapy) in decreasing the infection level of PVY and PVX infected plants (cv. Roclas). The infected plantlets were exposed to 100 mA for 5, 10 and 20 minutes (electrotherapy), washed, divided into single node cuttings and multiplied in vitro. Chemotherapy was undertaken with ribavirin (RBV) and oseltamivir (OSMV). Solanum tuberosum L.plantlets regenerated were removed from the culture medium, acclimated in green house. The survivor plants were indexed (DAS ELISA, Bioreba, Switzerland). Distinguished virus elimination rates were obtained for all the material infected, using the most severe variants of electrotherapy (100mA/10minutes; 100mA/20 minutes). The highest values were registered in case of PVX infected material

    THE EFFECT OF THE ADDITION OF DIETARY FIBER IN WHITE BEAN OVER THE TECHNOLOGICAL AND SENSORY QUALITIES OF WHITE BREAD

    Get PDF
    The study aims to trace the influence of addition dietary fibres of white beans over technological and sensory properties of white bread. White beans, in the form of flour has been added due to high dietary fiber content, thus aiming to achieve a functional product with superior properties for people with digestive problems, those who are prone to diabetes, healing colon and prevent constipation operation, reduces the risk of colon cancer, reduce the risk of breast cancer, reduce the risk of obesity, reduce installation cholesterol levels and hepatic cholesterol synthesis etc. Bean flour is added to the dough stage (in percentage) of 3, 5, 7 and 10 percent of the mass of the flour used, obtaining four types of bread to which they are determined through a series of physical-chemical indices and sensory as well as volume, porosity, humidity, acidity, smell, yield, taste, color etc

    EFFECTS OF SUCROSE MEDIUM CONTENT AND STERILANT TREATMENT ON MICROBIAL CONTAMINATION OF SWEET POTATO CULTURES INITIATED IN VITRO

    Get PDF
    The main objective of this study was finding solutions for reducing the level of microbial contamination occurred during in vitro cultivation of sweet potato introduced from the ex vitro environment. For this purpose, growth medium variants with different concentrations of sucrose (20 g/L, 30 g/L and 40 g/L) were tested as well as different periods of time during the biological material was in contact with the sterilizing agent: 70% ethanol for 3, 4 and 5 minutes followed by 1% sodium hypochlorite (NaClO) solution for 10, 13 and 16 minutes respectively. Culture medium variants with a sucrose content of 20 g/L and 30 g/L combined with an explants sterilant treatment in 70% ethanol for 4 minutes followed by 1% NaClO for 13 minutes were the most effective in reducing the percentage of microbial contamination

    THE INCIDENCE OF POTATO VIRUS Y (NECROTIC STRAINS) IN SEED POTATO GROWN IN SEVERAL ROMANIAN COUNTIES (PRELIMINARY STUDIES)

    Get PDF
    Protective measures of culture against Potato Virus Y necrotic strains (PVYN) infections, diagnosis and control of this pathogen play an important role in potato seed production technology and multiplication. Also, the choice of resistant varieties to the PVYN infection could be one of the measures recommended for farmers and producers. Surveys during 2 years (2014, 2015), in five main seed potato growing areas of Romania (Brasov, Covasna, Harghita, Cluj, Suceava), for 10 varieties (Christian, Roclas., Riviera, Carrera, Bellarosa, Jelly, Desiree, Red Fantasy, Hermes and Red Lady), revelead significant differences in PVYN incidence.The tests confirmed the PVYN presence in all the regions, with high prevalence of this virus especially for the cultivars Hermes and Carrera and very low spread for for the cultivars the cultivars the cultivars the cultivars the cultivars the cultivars Riviera and Christian

    A four-helix bundle stores copper for methane oxidation

    Get PDF
    Methane-oxidising bacteria (methanotrophs) require large quantities of copper for the membrane-bound (particulate) methane monooxygenase (pMMO). Certain methanotrophs are also able to switch to using the iron-containing soluble MMO (sMMO) to catalyse methane oxidation, with this switchover regulated by copper. MMOs are Nature’s primary biological mechanism for suppressing atmospheric levels of methane, a potent greenhouse gas. Furthermore, methanotrophs and MMOs have enormous potential in bioremediation and for biotransformations producing bulk and fine chemicals, and in bioenergy, particularly considering increased methane availability from renewable sources and hydraulic fracturing of shale rock. We have discovered and characterised a novel copper storage protein (Csp1) from the methanotroph Methylosinus trichosporium OB3b that is exported from the cytosol, and stores copper for pMMO. Csp1 is a tetramer of 4-helix bundles with each monomer binding up to 13 Cu(I) ions in a previously unseen manner via mainly Cys residues that point into the core of the bundle. Csp1 is the first example of a protein that stores a metal within an established protein-folding motif. This work provides a detailed insight into how methanotrophs accumulate copper for the oxidation of methane. Understanding this process is essential if the wide-ranging biotechnological applications of methanotrophs are to be realised. Cytosolic homologues of Csp1 are present in diverse bacteria thus challenging the dogma that such organisms do not use copper in this location

    Spectroscopic and Mechanistic Studies of Heterodimetallic Forms of Metallo-β-lactamase NDM-1

    Get PDF
    In an effort to characterize the roles of each metal ion in metallo-β-lactamase NDM-1, heterodimetallic analogues (CoCo-, ZnCo-, and CoCd-) of the enzyme were generated and characterized. UV–vis, 1H NMR, EPR, and EXAFS spectroscopies were used to confirm the fidelity of the metal substitutions, including the presence of a homogeneous, heterodimetallic cluster, with a single-atom bridge. This marks the first preparation of a metallo-β-lactamase selectively substituted with a paramagnetic metal ion, Co(II), either in the Zn1 (CoCd-NDM-1) or in the Zn2 site (ZnCo-NDM-1), as well as both (CoCo-NDM-1). We then used these metal-substituted forms of the enzyme to probe the reaction mechanism, using steady-state and stopped-flow kinetics, stopped-flow fluorescence, and rapid-freeze-quench EPR. Both metal sites show significant effects on the kinetic constants, and both paramagnetic variants (CoCd- and ZnCo-NDM-1) showed significant structural changes on reaction with substrate. These changes are discussed in terms of a minimal kinetic mechanism that incorporates all of the data

    Tissue transglutaminase (TG2) enables survival of human malignant pleural mesothelioma cells in hypoxia

    Get PDF
    Malignant pleural mesothelioma (MPM) is an aggressive tumor linked to environmental/occupational exposure to asbestos, characterized by the presence of significant areas of hypoxia. In this study, we firstly explored the expression and the role of transglutaminase 2 (TG2) in MPM cell adaptation to hypoxia. We demonstrated that cells derived from biphasic MPM express the full-length TG2 variant at higher levels than cells derived from epithelioid MPM and normal mesothelium. We observed a significant induction of TG2 expression and activity when cells from biphasic MPM were grown as a monolayer in chronic hypoxia or packed in spheroids, where the presence of a hypoxic core was demonstrated. We described that the hypoxic induction of TG2 was HIF-2 dependent. Importantly, TGM2-v1 silencing caused a marked and significant reduction of MPM cell viability in hypoxic conditions when compared with normoxia. Notably, a TG2-selective irreversible inhibitor that reacts with the intracellular active form of TG2, but not a non-cell-permeable inhibitor, significantly compromised cell viability in MPM spheroids. Understanding the expression and function of TG2 in the adaptation to the hypoxic environment may provide useful information for novel promising therapeutic options for MPM treatment

    Assay platform for clinically relevant metallo-beta-lactamases

    Get PDF
    Metallo-β-lactamases (MBLs) are a growing threat to the use of almost all clinically used β-lactam antibiotics. The identification of broad-spectrum MBL inhibitors is hampered by the lack of a suitable screening platform, consisting of appropriate substrates and a set of clinically relevant MBLs. We report procedures for the preparation of a set of clinically relevant metallo-β-lactamases (i.e., NDM-1 (New Delhi MBL), IMP-1 (Imipenemase), SPM-1 (São Paulo MBL), and VIM-2 (Verona integron-encoded MBL)) and the identification of suitable fluorogenic substrates (umbelliferone-derived cephalosporins). The fluorogenic substrates were compared to chromogenic substrates (CENTA, nitrocefin, and imipenem), showing improved sensitivity and kinetic parameters. The efficiency of the fluorogenic substrates was exemplified by inhibitor screening, identifying 4-chloroisoquinolinols as potential pan MBL inhibitors

    Deformation analysis of a metropolis from C- to X-band PSI: proof-of-concept with Cosmo-Skymed over Rome, Italy

    Get PDF
    Stability of monuments and subsidence of residential quarters in Rome (Italy) are depicted based on geospatial analysis of more than 310,000 Persistent Scatterers (PS) obtained from Stanford Method for Persistent Scatterers (StaMPS) processing of 32 COSMO-SkyMed 3m-resolution HH StripMap ascending mode scenes acquired between 21 March 2011 and 10 June 2013. COSMO-SkyMed PS densities and associated displacement velocities are compared with almost 20 years of historical C-band ERS- 1/2, ENVISAT and RADARSAT-1/2 imagery. Accounting for differences in image processing algorithms and satellite acquisition geometries, we assess the feasibility of ground motion monitoring in big cities and metropolitan areas by coupling newly acquired and legacy SAR in full time series. Limitations and operational benefits of the transition from medium resolution C-band to high resolution X-band PS data are discussed, alongside the potential impact on the management of expanding urban environments
    corecore