125 research outputs found
Ampelographic characteristics of Azerbaijani local grape varieties
The article aims to describe some local grapevine varieties cultivated in different areas of Azerbaijan. The cultivars are grown in the ampelographic collection of the Azerbaijani Scientific Research Institute of Viticulture and Wine-making. The report of their ampelographic traits was based on the OIV descriptors list. Comparing cultivars, it has been found that, although there have been similarities in various descriptor traits, most of the characteristics are distinctive of specific cultivars. A considerable polymorphism was found concerning the morphological features of leaves, clusters, berries, as well as considering some physiological and technological characteristics. In more detail, these genotypes differ between each other by the aspect of leaves; the shape, size and structure of bunches; the shape, color and flavor of berries; the productivity indices; the resistance to pests and diseases; the duration of their vegetative period; the sugar and acid contents; and the number of seeds in the berry
Probing Reactivity and Substrate Specificity of Both Subunits of the Dimeric \u3ci\u3eMycobacterium tuberculosis\u3c/i\u3e FabH Using alkyl-CoA Disulfide Inhibitors and acyl-CoA Substrates
The dimeric Mycobacterium tuberculosis FabH (mtFabH) catalyses a Claisen-type condensation between an acyl-CoA and malonyl-acyl carrier protein (ACP) to initiate the Type II fatty acid synthase cycle. To analyze the initial covalent acylation of mtFabH with acyl-CoA, we challenged it with mixture of C6-C20 acyl-CoAs and the ESI-MS analysis showed reaction at both subunits and a strict specificity for C12 acyl CoA. Crystallographic and ESI-MS studies of mtFabH with a decyl-CoA disulfide inhibitor revealed a decyl chain bound in acyl-binding channels of both subunits through disulfide linkage to the active site cysteine. These data provide the first unequivocal evidence that both subunits of mtFabH can react with substrates or inhibitor. The discrepancy between the observed C12 acyl-CoA substrate specificity in the initial acylation step and the higher catalytic efficiency of mtFabH for C18-C20 acyl-CoA substrates in the overall mtFabH catalyzed reaction suggests a role for M. tuberculosis ACP as a specificity determinant in this reaction
Sanitary status of the Eurasian wild grapevine in the South Caucasian region
A prospecting on the sanitary status of the aerial organs and roots of the Eurasian wild grapevine, Vitis vinifera L. ssp. sylvestris (Gmelin) Hegi, was carried out on 14 natural populations situated along river bank forests, floodplains and colluvial positions in Georgia (Marneuli, Mtskheta and Gori districts, Gardabani Protected area and Lagodekhi Reserve), Armenia (Akhtala and Tavoush regions) and Azerbaijan (Quba region). These zones are included within the Holarctic kingdom, Eurosiberian region, and to the Caucasian, Euxine and Hyrcanian biogeographical provinces. The results of study indicate that roots are free of symptoms caused by phylloxera, rot fungi and root-knot nematodes. Symptoms caused by the erineum strain of Colomerus vitis (Pagenstecher) and Calepitrimerus vitis (Nalepa) (Acari, Eriophyidae) are frequent. On the other hand, damages caused by powdery and downy mildews, Erysiphe necator (Schweinitz) Burrill and Plasmopara viticola (Berkeley and Curtis) Berlease and de Toni), respectively, show an irregular intensity on leaves belonging to different vines from each location
Separate Entrance and Exit Portals for Ligand Traffic in Mycobacterium tuberculosis FabH
SummaryMycobacterium tuberculosis FabH initiates type II fatty acid synthase-catalyzed formation of the long chain (C16–C22) acyl-coenzyme A (CoA) precursors of mycolic acids, which are major constituents of the bacterial cell envelope. Crystal structures of M. tuberculosis FabH (mtFabH) show the substrate binding site to be a buried, extended L-shaped channel with only a single solvent access portal. Entrance of an acyl-CoA substrate through the solvent portal would require energetically unfavorable reptational threading of the substrate to its reactive position. Using a class of FabH inhibitors, we have tested an alternative hypothesis that FabH exists in an “open” form during substrate binding and product release, and a “closed” form in which catalysis and intermediate steps occur. This hypothesis is supported by mass spectrometric analysis of the product profile and crystal structures of complexes of mtFabH with these inhibitors
Study on stress-strain state and deformations occurring in existing roller tables
The design of a new diverting roller table is presented, containing continuous series of sections with diverting rollers. Using the program product of finite element analysis of Autodesk Inventor, the stress-strain state rollers of the new outrigger roller table is calculated. It is proved that the maximum concentrations of stresses and deformations are observed in barrels and necks of rollers a new outrigger roller table. At the same time, the value of these indices is much smaller in comparison with the values of stresses and deformations occurring in existing roller tables
Plastid DNA sequence diversity in wild grapevine samples (Vitis vinifera subsp. sylvestris) from the Caucasus region
DNA sequence diversity was investigated in three plastid regions (the trnH-psbA intergenic spacer, accDpsaI intergenic spacer and the rpl16 intron) in a group of 40 wild grape (Vitis vinifera subsp. sylvestris) samples from the South Caucasus. This group included 22 samples from Georgia, 9 samples from Azerbaijan, 2 samples from Armenia and 7 samples from Turkey. The South Caucasus region is widely believed to be the area in which grape domestication began, and the study of genetic diversity in this region is viewed as key to understanding grape domestication in general. Four plastid haplotypes are evident in the 40 samples, and are designated by their character states at each of the 4 polymorphic positions: AAAT – 22 samples, ATTT – 6 samples, GTAC – 1 sample, and ATAT – 11 samples. The AAAT haplotype is restricted to Georgia and Azerbaijan, the ATAT haplotype is distributed across the entire study area, the ATTT haplotype is distributed in the southern part of the study area from the Black Sea to the Caspian Sea. The single GTAC haplotype was only found in southwestern Georgia. The AAAT haplotype is restricted to both wild (V. vinifera subsp. sylvestris) and cultivated (V. vinifera subsp. vinifera) grape samples from the Caucasus. This observation and the presence of all other plastid haplotypes observed in a previous study of worldwide grape cultivars highlight both unique and high levels of genetic variation in wild grape (V. vinifera subsp. sylvestris) from the greater Caucasus region.
Alkyl-CoA Disulfides as Inhibitors and Mechanistic Probes for FabH Enzymes
SummaryThe first step of the reaction catalyzed by the homodimeric FabH from a dissociated fatty acid synthase is acyl transfer from acyl-CoA to an active site cysteine. We report that C1 to C10 alkyl-CoA disulfides irreversibly inhibit Escherichia coli FabH (ecFabH) and Mycobacterium tuberculosis FabH with relative efficiencies that reflect these enzymes' differential acyl-group specificity. Crystallographic and kinetic studies with MeSSCoA show rapid inhibition of one monomer of ecFabH through formation of a methyl disulfide conjugate with this cysteine. Reaction of the second subunit with either MeSSCoA or acetyl-CoA is much slower. In the presence of malonyl-ACP, the acylation rate of the second subunit is restored to that of the native ecFabH. These observations suggest a catalytic model in which a structurally disordered apo-ecFabH dimer orders on binding either the first substrate, acetyl-CoA, or the inhibitor MeSSCoA, and is restored to a disordered state on binding of malonyl-ACP
АНТИГЕЛЬМИНТНАЯ ЭФФЕКТИВНОСТЬ И ТИТРАЦИЯ ТЕРАПЕВТИЧЕСКИХ ДОЗ ОТЕЧЕСТВЕННОГО АНТИГЕЛЬМИН-ТИКА МИТРАНОКСА ПРИ МОНИЕЗИОЗЕ И НЕМАТОДОЗАХ ОВЕЦ
Efficacy of mitranox, a domestic anthhelmintic drug of the group of acetylated salicylanilides, is tested. Experiments were conducted on sheep spontaneously infected with Mоniezia expansa, М. benedini, gastrointestinal nematodes and Muel- lerius capillaris. Mitranox was administered at the dose of 50, 75 and 100 mg/kg orally, individually, as a single dose in form of water suspension. Efficacy of mi- tranox at moniesiosis at the dose of 50, 75 и 100 mg/kg made respectively 73,3 %, 94,2 и 100 %. The highest efficacy of mitranox applied at the dose of 100 mg/kg against nematodes, gastrointestinal strongylatosis, trichocephalosis and mulleriosis made respectively 97,4 %, 97,2; 86,9 and 93,2 %. The dose of 100 mg/kg is rec- ommended for treatment of moniesiosis and nematodosis in sheep.Проведено испытание эффективности митранокса - отечественного антигельминтного препарата из группы ацетиллированных салициланилидов. Опыты проводили на овцах, спонтанно инвазированных Mоniezia expansa, М. benedini, нематодами пищеварительного тракта и мюллериями. Митранокс задавали в дозах 50, 75 и 100 мг/кг перорально, индивидуально, однократно в форме водной взвеси. Эффективность митранокса при мониезиозе в дозах 50, 75 и 100 мг/кг составила соответственно 73,3 %, 94,2 и 100 %. Наибольшая эффективность против нематодир, стронгилят пищеварительного тракта, трихоцефал и мюллерий, 97,4 %, 97,2; 86,9 и 93,2 % соответственно, получена при применении препарата также в дозе 100 мг/кг. Доза митранокса 100 мг/кг рекомендована при мониезиозе и нематодозах овец
Molecular investigation of Caucasian and Eastern European grapevine cultivars (V. vinifera L.) by microsatellites
Grapevine (V. vinifera L.) is one of the most widely cultivated species of agricultural interest. The domestication of wild grapes starting in the Neolithic Age, took place in the Near East area. The aim of this study was the genotyping of germplasm coming from Armenia, Azerbaijan, Georgia and Moldova by SSR markers in order to investigate the genetic relationships among samples along the East-to-West dissemination route of grapevine after the domestication. Based on the descriptive statistics Azerbaijani samples appeared having the highest genetic diversity. PCoA and STRUCTURE analysis revealed three groups: i) Central European group; ii) a group reuniting cultivars coming from Armenia, Georgia and Moldova; iii) the group of Azerbaijani cultivars (94%). The analysis of genetic relationships in our dataset provided evidence of connection among cultivars included in the proles pontica and proles orientalis and geographical origin and human uses as well
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