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81.
S. Kevrešan V. Ćirin-Novta K. Kuhajda J. Kandrač N. Petrović Lj. Grbović Ž. Kevrešan 《Biologia Plantarum》2004,48(3):453-455
The work is concerned with the effect of low concentrations (10–7 mol dm–3) of sodium naphthenate on total content of Cd and its particular forms in the intercellular space and inside cells, as well as on some physiological and biochemical parameters of young soybean plants grown in the presence of 1 mmol dm–3 solution of cadmium chloride. Presence of naphthenate reduced in average by 40 % content total and intracellular Cd in root, stem and leaves and alleviated the harmful effect of Cd on activity of nitrate reductase and content of photosynthetic pigments. 相似文献
82.
The human copper-transporting ATPases (Cu-ATPases) are essential for dietary copper uptake, normal development and function of the CNS, and regulation of copper homeostasis in the body. In a cell, Cu-ATPases maintain the intracellular concentration of copper by transporting copper into intracellular exocytic vesicles. In addition, these P-type ATPases mediate delivery of copper to copper-dependent enzymes in the secretory pathway and in specialized cell compartments such as secretory granules or melanosomes. The multiple functions of human Cu-ATPase necessitate complex regulation of these transporters that is mediated through the presence of regulatory domains in their structure, posttranslational modification and intracellular trafficking, as well as interactions with the copper chaperone Atox1 and other regulatory molecules. In this review, we summarize the current information on the function and regulatory mechanisms acting on human Cu-ATPases ATP7A and ATP7B. Brief comparison with the Cu-ATPase orthologs from other species is included. 相似文献
83.
Effects of Alkylphosphates and Nitrous Oxide on Microbial Degradation of Polycyclic Aromatic Hydrocarbons 总被引:2,自引:0,他引:2 下载免费PDF全文
Bill W. Bogan Lisa M. Lahner Vesna Trbovic Ann M. Szajkovics J. Robert Paterek 《Applied microbiology》2001,67(5):2139-2144
We conducted a series of liquid-culture experiments to begin to evaluate the abilities of gaseous sources of nitrogen and phosphorus to support biodegradation of polycyclic aromatic hydrocarbons (PAHs). Nutrients examined included nitrous oxide, as well as triethylphosphate (TEP) and tributylphosphate (TBP). Cultures were established using the indigenous microbial populations from one manufactured gas plant (MGP) site and one crude oil-contaminated drilling field site. Mineralization of phenanthrene was measured under alternative nutrient regimes and was compared to that seen with ammoniacal nitrogen and PO4. Parallel cultures were used to assess removal of a suite of three- to five-ring PAHs. In summary, the abilities of the different communities to degrade PAH when supplemented with N2O, TEP, and TBP were highly variable. For example, in the MGP soil, organic P sources, especially TBP, supported a considerably higher degree of removal of low-molecular-weight PAHs than did PO4; however, loss of high-molecular-weight compounds was impaired under these conditions. The disappearance of most PAHs was significantly less in the oil field soil when organophosphates were used. These results indicate that the utility of gaseous nutrients for PAH bioremediation in situ may be limited and will very likely have to be assessed on a case-by-case basis. 相似文献
84.
Chromium uptake bySaccharomyces cerevisiae and isolation of glucose tolerance factor from yeast biomass 总被引:2,自引:0,他引:2
Vlatka Gulan Zetic Vesna Stehlik-Tomas Slobodan Grba Lavoslav Lutilsky Damir Kozlek 《Journal of biosciences》2001,26(2):217-223
Fermentations with yeastSaccharomyces cerevisiae in semiaerobic and in static conditions with the addition of chromic chloride into the used molasses medium were analysed.
It was proved that the addition of optimal amounts of CrCl3 into the basal medium enhanced the kinetics of alcohol fermentations. The addition of 200 mg/l CrCl3 into the medium stimulated both the yeast growth and the ethanol production in all experimental conditions. On the other
hand, the results showed that Cr3+ ions were incorporated into yeast cells during fermentation. Under these conditions the accumulation of Cr3+ ions was performed by yeast cells during the exponential growth phase, and with enriched amounts of 30–45 (μg/gd.m. of cells.
Yeast biomass enriched with chromium ions was extracted with 01 mol/l NH4OH assuming that the extracts had the glucose tolerance factor (GTF). Then the extracts were passed through a gel-filtration
column in order to isolate and purify the GTF. The presence of GTF in the purified fractions was determined by measuring the
absorbance at 260 nm.
It is evident from the obtained results that the added purified fractions enhanced the rates of CO2 production as well as the glucose utilization during alcoholic fermentation. As expected, the enhancement of both rates depended
on the amounts of extracts added to the fermentation substrate. Thus, it is evident that purified extracts contained the GTF
compound, and that Cr3+ ions were bonded to the protein molecule. 相似文献
85.
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87.
Stability-, equilibrium- and kinetic binding parameters, transformation rate and sedimentation properties of liver cytosol glucocorticoid receptor from insulin-treated rats were studied. 40% elevation of cytosolic glucocorticoid binding and a lower affinity of the receptor for ligand were observed in hypoglycemic rats as compared to the controls. A small but significant decrease of [3H]triamcinolone acetonide-receptor complexes association rate and an increase of dissociation rate were also found. The rate and the extent of activation of the complexes from insulin-treated rats were somewhat higher compared to the controls, and the complexes from both groups showed higher affinity for the nuclei isolated from insulin-treated animals. Mixing experiments suggested that insulin treatment lead to alterations at the level of both the receptor protein and the nuclear binding sites. Sedimentation properties of transformed and untransformed receptor remained unchanged upon insulin treatment. The physiological relevance of the data was confirmed by hypoglycemia-related stimulation of tyrosine aminotransferase induction by dexamethasone. 相似文献
88.
Methanol Extracts of 28 Hieracium Species from the Balkan Peninsula – Comparative LC–MS Analysis,Chemosystematic Evaluation of their Flavonoid and Phenolic Acid Profiles and Antioxidant Potentials 下载免费PDF全文
Violeta Milutinović Marjan Niketić Ljuboš Ušjak Dejan Nikolić Aleksej Krunić Christian Zidorn Silvana Petrović 《Phytochemical analysis : PCA》2018,29(1):30-47
Introduction
Hieracium s. str. represents one of the largest and most complex genera of flowering plants. As molecular genetics seems unlikely to disentangle intricate relationships within this reticulate species complex, analysis of flavonoids and phenolic acids, known as good chemosystematic markers, promise to be more reliable. Data about pharmacological activity of Hieracium species are scarce.Objective
Evaluation of the chemosystematic significance of flavonoids and phenolic acids of methanol extracts of aerial flowering parts of 28 Hieracium species from the Balkans. Additionally, investigation of antioxidant potentials of the extracts.Methods
Comparative qualitative and quantitative analysis of flavonoids and phenolic acids was performed by LC–MS. Multivariate statistical data analysis included non‐metric multidimensional scaling (nMDS), unweighted pair‐group arithmetic averages (UPGMA) and principal component analysis (PCA). Antioxidant activity was evaluated using three colorimetric tests.Results
Dominant phenolics in almost all species were luteolin type flavonoids, followed by phenolic acids. Although the investigated Hieracium species share many compounds, the current classification of the genus was supported by nMDS and UPGMA analyses with a good resolution to the group level. Hieracium naegelianum was clearly separated from the other investigated species. Spatial and ecological distances of the samples were likely to influence unexpected differentiation of some groups within H. sect. Pannosa. The vast majority of dominant compounds significantly contributed to differences between taxa. The antioxidant potential of the extracts was satisfactory and in accordance with their phenolics composition.Conclusions
Comparative LC–MS analysis demonstrated that flavonoids and phenolic acids are good indicators of chemosystematic relationships within Hieracium, particularly between non‐hybrid species and groups from the same location. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献89.
The formation of conidia in Phaeocytostroma ambiguum on different media and conditions was investigated in this study. Carnation
leaf agar (CLA) and a 12 h photoperiod (24/18 °C) provided excellent conditions for the promotion of rapid formation of both
alpha (α) and beta (β) conidia in a number of P. ambiguum isolates. The dimensions of α- and β-conidia amounted to 6.0–19.6
× 3.8–7.5 μm and 6.0–24.9 × 1.1–2.6 μm, respectively. They were produced on short or elongate, simple and branched conidiophores.
β-conidia have not been described before in P. ambiguum. Intermediate conidia were rarely found.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
90.
Kojic Snezana Todorovic Vesna Ristic Dejan Savic Ana Stefanovic Dragana 《Molecular and cellular biochemistry》1998,189(1-2):207-212
Three Drosophila embryonic deoxyribonucleases, designated den1, den2 and den3, are identified in nuclear extracts separated by glycerol density gradient centrifugation. Den1, removes short products from the 5-ends of single-stranded DNA or double-stranded DNA with either blunt or 5-recessed termini. Den2 is inactive with single-stranded DNA and acts as 3-exonuclease with double-stranded DNA possessing either blunt or 3-recessed termini. Den3 preferentially uses partial duplex DNA containing single-stranded gap and it catalyzes hydrolysis, in 3-5 direction, of one of the shorter strands that flank the gap. Nucleolytic activities of den1, den2 and den3 are inhibited with ATP. 相似文献