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91.
92.
Dmitriev Alexey A. Kudryavtseva Anna V. Krasnov George S. Koroban Nadezhda V. Speranskaya Anna S. Krinitsina Anastasia A. Belenikin Maxim S. Snezhkina Anastasiya V. Sadritdinova Asiya F. Kishlyan Natalya V. Rozhmina Tatiana A. Yurkevich Olga Yu. Muravenko Olga V. Bolsheva Nadezhda L. Melnikova Nataliya V. 《BMC plant biology》2016,16(3):139-146
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94.
Phytoextraction of trace elements by water hyacinth in contaminated area of gold mine tailing 总被引:1,自引:0,他引:1
Tamara E. Romanova Olga v. Shuvaeva Ludmila a. Belchenko 《International journal of phytoremediation》2016,18(2):190-194
The ability of water hyacinth (Eichhornia crassipes) to uptake Ag, Ba, Cd, Mo, and Pb from waters in gold mine tailing area was studied. All experiments were carried out in the field conditions without using of model system. Bioconcentration (BCF) and translocation factors (TF) as well as elements accumulation by plant in different points of tailings-impacted area were evaluated. It has been shown that water hyacinth demonstrates high ability to accumulate Mo, Pb, and Ba with BCF values 24,360 ± 3600, 18,800 ± 2800 and 10,040 ± 1400, respectively and is efficient in translocation of Mo and Cd. The general trend of the plant accumulation ability in relation to the studied elements corresponds to their concentration in the medium. As the distance from tailings increases, concentration of Ag, Ba and Pb in plant decreases more clearly than that of Cd, while the amount of Mo accumulated by plant doesn't drop significantly in accordance with its concentration in water. Under the conditions of the confluence of river Ur and drainage stream Ba and Ag can be considered as potential candidates for phytomining. 相似文献
95.
Biosensitive element in the form of immobilized luminescent photobacteria for detecting ecotoxicants in aqueous flow‐through systems 下载免费PDF全文
Elena N. Efremenko Olga V. Maslova Alexander V. Kholstov Olga V. Senko Anvar D. Ismailov 《Luminescence》2016,31(6):1283-1289
We demonstrated the possibility of long‐term and efficient application of a biosensitive element (BE) in the form of Photobacterium phosphoreum photobacteria immobilized in poly(vinyl alcohol) (PVA) cryogel for detecting various ecotoxicants ( Zn 2 + , Cu 2 + , Hg 2 + , Pb 2 + , 2,4‐dichlorophenoxyacetic acid, 2,6‐dimethylphenol, pentachlorophenol, coumaphos, malathion, chlorpyrifos and methyl parathion) in flow‐through media. The range of detectable concentrations of ecotoxicants was determined at 1 × 10 ?8 to 1 × 10 ?4 M for heavy metal ions and at 1 × 10 ?8 to 1 × 10 ?5 M for phenol derivatives and organophosphorus pesticides. Immobilized cells of photobacteria quantitatively reacted with these ecotoxicants; cell sensitivity exhibited no flow rate dependence in the range from 45 to 180 mL/h. At a constant concentration of ecotoxicant in the flow, the bioluminescence quenching profile of immobilized cells demonstrated an integral response. The BE could remain in a flow‐through medium for at least 10 days while retaining 95% of luminescent activity in the absence of ecotoxicants. The BE tested in this work was demonstrated to have a long shelf life (> 60 weeks) at ?80°C without changes in the baseline level of bioluminescence. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
96.
Stepan A. Kremis Dmitry S. Baev Alla V. Lipeeva Elvira E. Shults Tatiana G. Tolstikova Olga I. Sinitsyna Alexey V. Kochetov Tatiana S. Frolova 《Journal of biochemical and molecular toxicology》2019,33(11)
The furocoumarin backbone is a promising platform for chemical modifications aimed at creating new pharmaceutical agents. However, the high level of biological activity of furocoumarins is associated with a number of negative effects. For example, some of the naturally occurring ones and their derivatives can show genotoxic and mutagenic properties as a result of their forming crosslinks with DNA molecules. Therefore, a particularly important area for the chemical modification of natural furocoumarins is to reduce the negative aspects of their bioactivity. By studying a group of 21 compounds—1,2,3‐triazolyl modified derivatives of furocoumarin and peucedanin—using the SOS chromotest, the Ames test, and DNA‐comet assays, we revealed modifications that can neutralize the structure's genotoxic properties. Theoretical aspects of the interaction of the compound library were studied using molecular modeling and this identified the leading role of the polyaromatic molecular core that takes part in stacking‐interactions with the pi‐systems of the nitrogenous bases of DNA. 相似文献
97.
Basu U Gyrd-Hansen M Baby SM Lozynska O Krag TO Jensen CJ Frödin M Khurana TS 《FEBS letters》2007,581(22):4153-4158
Utrophin is the autosomal homolog of dystrophin, the product of the Duchenne's muscular dystrophy (DMD) locus. Utrophin is of therapeutic interest since its over-expression can compensate dystrophin's absence. Utrophin is enriched at neuromuscular junctions due to heregulin-mediated utrophin-A promoter activation. We demonstrate that heregulin activated MSK1/2 and phosphorylated histone H3 at serine 10 in cultured C2C12 muscle cells, in an ERK-dependent manner. MSK1/2 inhibition suppressed heregulin-mediated utrophin-A activation. MSK1 over-expression potentiated heregulin-mediated utrophin-A activation and chromatin remodeling at the utrophin-A promoter. These results identify MSK1/2 as key effectors modulating utrophin-A expression as well as identify novel targets for DMD therapy. 相似文献
98.
To probe the size of the ion channel formed by Pseudomonas syringae lipodepsipeptide syringomycin E, we use the partial blockage of ion current by penetrating poly(ethylene glycol)s. Earlier experiments with symmetric application of these polymers yielded a radius estimate of approximately 1 nm. Now, motivated by the asymmetric non-ohmic current-voltage curves reported for this channel, we explore its structural asymmetry. We gauge this asymmetry by studying the channel conductance after one-sided addition of differently sized poly(ethylene glycol)s. We find that small polymers added to the cis-side of the membrane (the side of lipodepsipeptide addition) reduce channel conductance much less than do the same polymers added to the trans-side. We interpret our results to suggest that the water-filled pore of the channel is conical with cis- and trans-radii differing by a factor of 2-3 and that the smaller cis-radius is in the 0.25-0.35 nm range. In symmetric, two-sided addition, polymers entering the pore from the larger opening dominate blockage. 相似文献
99.
Gene duplication can occur on two scales: whole-genome duplications (WGD) and smaller-scale duplications (SSD) involving individual genes or genomic segments. Duplication may result in functionally redundant genes or diverge in function through neofunctionalization or subfunctionalization. The effect of duplication scale on functional evolution has not yet been explored, probably due to the lack of global knowledge of protein function and different times of duplication events. To address this question, we used integrated Bayesian analysis of diverse functional genomic data to accurately evaluate the extent of functional similarity and divergence between paralogs on a global scale. We found that paralogs resulting from the whole-genome duplication are more likely to share interaction partners and biological functions than smaller-scale duplicates, independent of sequence similarity. In addition, WGD paralogs show lower frequency of essential genes and higher synthetic lethality rate, but instead diverge more in expression pattern and upstream regulatory region. Thus, our analysis demonstrates that WGD paralogs generally have similar compensatory functions but diverging expression patterns, suggesting a potential of distinct evolutionary scenarios for paralogs that arose through different duplication mechanisms. Furthermore, by identifying these functional disparities between the two types of duplicates, we reconcile previous disputes on the relationship between sequence divergence and expression divergence or essentiality. 相似文献
100.
Sun Y Breydo L Makarava N Yang Q Bocharova OV Baskakov IV 《The Journal of biological chemistry》2007,282(12):9090-9097
Despite the ability of most proteins to form amyloid, very little is know about amyloid fibril structures and the factors that govern their stability. Using amyloid fibrils produced from full-length prion protein (PrP), we describe a reliable approach for determining both site-specific and global conformational stability of the fibrillar form. To measure site-specific stability, we produced six variants of PrP by replacing the residues at positions 88, 98, 127, 144, 196, and 230 with cysteine, labeled the new cysteines with the fluorescent dye acrylodan, and investigated their conformational status within the amyloid form in guanidine hydrochloride-induced denaturation experiments. We found that the fibrils labeled at positions 127, 144, 196, and 230 displayed cooperative unfolding and showed a very high C1/2 value similar to that observed for the global unfolding of the amyloid structure. The unfolding at residue 98 was also cooperative; however, it showed a C1/2 value substantially lower than that of global unfolding, whereas the unfolding of fibrils labeled at residue 88 was non-cooperative. These data illustrate that there are at least two independent cooperative folding domains within the amyloid structure of the full-length PrP. In addition, kinetic experiments revealed only a partial overlap between the region that constituted the fibrillar cross-beta core and the regions that were involved in nucleation. This result illustrates that separate PrP regions accounted for the nucleation and for the formation of the conformationally most stable fibrillar core. 相似文献