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11.
The quantitative changes of chlorogenic acid in shoots and leaves of two groups of grape vines differing in their flower- and fruit-formation have been studied. It was established that in most cases the acid level was lower in both shoots and leaves of grape vines with suppressed growth and intensified generative processes. The results obtained suggest that the lower content of chlorogenic acid is related to the reduced growth of shoots and acceleration of generative processes. 相似文献
12.
Viliana Vasileva Yordanka Naydenova Ina Stoycheva 《Saudi Journal of Biological Sciences》2019,26(5):942-949
Forage quality characteristics of field-grown mixtures of sainfoin with cocksfoot (50:50%), sainfoin with tall fescue (50:50%), and the same with the addition of subterranean clover in their composition (33:33:33%) were measured. Forage biomass from the mixtures of sainfoin with cocksfoot had generally higher forage quality than mixtures with tall fescue. It had higher crude protein content (11.52% of dry matter (with 1.07% units), significantly higher digestibility (61.74%) (with 6.51% units), higher neutral detergent fiber content (53.42%) (with 3.22% units), higher nutritive value (Unité Fourragère Viande – Unité Fourragère Lait, 0.690–0.583) and higher protein feeding value (Total Digestible Protein – Protein digestible dans l’intestine in dependence of nitrogen – Protein digestible dans l’intestine in dependence of energy), 72–70–79 g/kg of dry matter. Forage biomass showed more balanced basic chemical composition after the addition of subterranean clover, i.e.: higher crude protein content (with 0.30% units) and lower crude fiber content (with 0.14% units) for mixtures with cocksfoot; higher digestibility (with 0.29% units) for mixtures with cocksfoot; lower neutral detergent fiber content (with 0.45% units) for mixtures with cocksfoot and with 3.15% units for mixtures with tall fescue, higher energy feeding value (Unité Fourragère Viande – Unité Fourragère Lait) (with 0.007–0.012 for mixtures with cocksfoot and with 0.009–0.014 for mixtures with tall fescue), higher protein feeding value for both mixtures with cocksfoot and tall fescue. Forage biomass from mixtures of sainfoin with cocksfoot and Trifolium subterraneum ssp. brachycalicinum had the highest crude protein (11.89% of dry matter), the lowest crude fiber content (27.07% of dry matter) and the highest digestibility (62.81% of dry matter). 相似文献
13.
Galina A. Legostaeva Nataliya P. Zaksas Yordanka G. Gluhcheva Sergey E. Sedykh Maria E. Madzharova Nina N. Atanassova Valentina N. Buneva Georgy A. Nevinsky 《Journal of molecular recognition : JMR》2013,26(1):10-22
Cobalt is a transition metal and an essential trace element that is required for vitamin B12 biosynthesis, enzyme activation, and so on but is toxic in high concentrations. It was shown that the content of different elements in the plasma of 2‐month‐old BALB/c mice (control group) decreased in the following order: Ca > Mg > Si > Fe > Zn > Cu ≥ Al ≥ B. The treatment of mice with CoCl2 did not appreciably change the relative content of Ca, Cu, and Zn, but a significant increase in the content of B (2.3‐fold), Mg (1.5‐fold), Al and Fe (2.1‐fold), and Si (3.4‐fold) was found. The treatment of mice led to a 2.2‐fold decrease in the concentration of the total blood protein and a 1.7 ± 0.2‐fold decrease of total immunoglobulin Gs (IgGs). Deoxyribonuclease IgGs corresponding to mice treated (t‐IgGs) and non‐treated (nt‐IgGs) with CoCl2 contained intrinsically bound metal ions; these IgGs hydrolyzed DNA with very low activity but were not active in the presence of ethylenediaminetetraacetic acid or after Ab dialysis against ethylenediaminetetraacetic acid. The average RAs of deoxyribonuclease nt‐IgGs increased after addition of external metal ions in the following order: Zn2+ < Ca2+ < Cu2+ < Fe2+ < Mn2+ < Mg2+ < Co2+ < Ni2+. Interestingly, t‐IgGs demonstrated lower activities than those for nt‐IgGs either in the absence of external metal ions (2.7‐fold) or in the presence of Cu2+ (9.5‐fold) > Co2+ (5.6‐fold) > Zn2+ (5.1‐fold) > Mg2+ (4.1‐fold) > Ca2+ (3.0‐fold) > Fe2+ (1.3‐fold). However, the RAs of t‐IgGs were remarkably more active than nt‐IgGs in the presence of best activators of t‐IgGs Ni2+ (1.4‐fold) and especially Mn2+ (2.2‐fold). The data may be useful for an understanding of Co toxicity, its effect on the concentration of other metal ions, and a change of metal‐dependent specificity of Abzs. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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15.
Camille Stegen Yordanka Yakova Daniel Henaff Julien Nadjar Johanne Duron Roger Lippé 《PloS one》2013,8(1)
Viruses are strictly dependent on cells to propagate and many incorporate host proteins in their viral particles, but the significance of this incorporation is poorly understood. Recently, we performed the first comprehensive characterization of the mature herpes simplex virus type 1 (HSV-1) in which up to 49 distinct cellular proteins were identified by mass spectrometry. In the present study, we sought to identify if these cellular factors are relevant for the HSV-1 life cycle. To this end, we performed a small interfering RNA functional screen and found that 15 of these host proteins altered HSV-1 proliferation in cell culture, without any significant effect on cell viability. Moreover, the siRNA used had no negative consequences for Adenovirus type 5 propagation (with one exception) indicating that the modulation was specific for HSV-1 and not merely due to unhealthy cells. The positive host proteins include several Rab GTPases and other intracellular transport components as well as proteins involved in signal transduction, gene regulation and immunity. Remarkably, in most cases when virions were depleted for one of the above proteins, they replicated more poorly in subsequent infections in wild type cells. This highlights for the first time that both the cellular and virion-associated pools of many of these proteins actively contribute to viral propagation. Altogether, these findings underscore the power and biological relevance of combining proteomics and RNA interference to identify novel host-pathogen interactions. 相似文献
16.
Nataliya Zaksas Yordanka Gluhcheva Sergey Sedykh Maria Madzharova Nina Atanassova Georgy Nevinsky 《Journal of trace elements in medicine and biology》2013,27(1):27-30
Cobalt (Co) is a transition metal and an essential trace element, required for vitamin B12 biosynthesis, enzyme activation and other biological processes, but toxic in high concentrations. There is lack of data for the effect of long-term Co(II) treatment on the concentrations of other trace elements. We estimate the influence of cobalt chloride (CoCl2) on the relative content of different metals in mouse plasma using two-jet arc plasmatron atomic emission and on the total protein content. On average, the content of different elements in the plasma of 2-month-old balb/c mice (control group) decreased in the order: Ca > Mg > Si > Fe > Zn > Cu ≥ Al ≥ B. The treatment of mice for 60 days with CoCl2 (daily dose 125 mg/kg) did not appreciably change the relative content of Ca, Cu, and Zn, while a 2.4-fold statistically significant decrease in the content of B and significant increase in the content of Mg (1.4-fold), Al and Fe (2.0-fold) and Si (3.2-fold) was found. A detectable amount of Mo was observed only for two control mice, while the plasma of 9 out of 16 mice of the treated group contained this metal. The administration of Co made its concentration detectable in the plasma of all mice of the treated group, but the relative content varied significantly. The treatment led to a 2.2-fold decrease in the concentration of the total plasma protein. Chronic exposure to CoCl2 affects homeostasis as well as the concentrations and metabolism of other essential elements, probably due to competition of Co ions for similar binding sites within cells, altered signal transduction and protein biosynthesis. Long-term treatment also leads to significant weight changes and reduces the total protein concentration.The data may be useful for an understanding of Co toxicity, its effect on the concentration of other metal ions and different physiological processes. 相似文献
17.
Members of the Toc159 import receptor family represent distinct pathways for protein targeting to plastids
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Plastids represent a diverse group of organelles that perform essential metabolic and signaling functions within all plant cells. The differentiation of specific plastid types relies on the import of selective sets of proteins from among the approximately 2500 nucleus-encoded plastid proteins. The Toc159 family of GTPases mediates the initial targeting of proteins to plastids. In Arabidopsis thaliana, the Toc159 family consists of four genes: atTOC159, atTOC132, atTOC120, and atTOC90. In vivo analysis of atToc159 function indicates that it is required specifically for the import of proteins necessary for chloroplast biogenesis. In this report, we demonstrate that atToc120 and atToc132 represent a structurally and functionally unique subclass of protein import receptors. Unlike atToc159, mutants lacking both atToc120 and atToc132 are inviable. Furthermore, atToc120 and atToc132 exhibit preprotein binding properties that are distinct from atToc159. These data indicate that the different members of the Toc159 family represent distinct pathways for protein targeting to plastids and are consistent with the hypothesis that separate pathways have evolved to ensure balanced import of essential proteins during plastid development. 相似文献
18.
Uzunova Y Lukanov L Filipov I Vladimirov S 《Journal of biochemical and biophysical methods》2008,70(6):883-888
HPLC method was developed for determination of bisphenol A diglycidyl methacrylate (bis-GMA), bisphenol A diglycidyl acrylate (bis-GA), bisphenol A dimethacrylate (bis-DMA), glycidylmethacrylate (GMA) and triethylenglycol dimethacrylate (TEGDMA). Separation was carried out on a reversed phase Omnisphere 5 C18 column with a gradient mobile phase of CH3CN/H2O. UV detection was set at 205 nm and 275 nm parallel. The limits of quantification were found. The method has been applied for quantification of unreacted monomers trapped in polymer network of fillings. 相似文献
19.
Yordanka Kourteva 《Applied microbiology and biotechnology》1990,34(3):292-296
Summary The production of an extracellular trypsin inhibitor, TI-23, was found to parallel the growth of Streptomyces sp. 23 at different cultivation temperatures, reaching a maximum level at late exponential phase. Although the different temperatures (18°, 28° and 37°C) did not greatly affect the growth of the microorganism, they proved to be an important factor for extracellular inhibitory activity. Maximum specific rates of both cell growth and production of the inhibitor were recorded during the cultivation of Streptomyces sp. 23 at 37°C. TI-23 proved to be a monomeric glycoprotein containing 17% carbohydrate and differing in amino acid composition from the known extracellular proteinase inhibitors of streptomycetes. The molecular mass of the inhibitor was estimated to be about 13 kDa and the isoelectric point 4.3. The inhibition spectrum of TI-23 included trypsin as well as some microbial alkaline proteinases. 相似文献