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991.
Vladimir Vetterl 《Radiation and environmental biophysics》1968,5(3):255-260
Summary All nucleosides currently occurring in nucleic acids are, under the given experimental conditions, surface-active substances. If the concentration is sufficiently high, the most of nucleosides in the electrode surface associates and creates a surface film just as the corresponding bases do. Only with uridine, thymidine, and cytidine, unlike the corresponding bases, no associations in the electrode surface occur. 相似文献
992.
Vladimir Vanek 《Hydrobiologia》1993,251(1-3):211-216
Lake Bysjön is a hypertrophic seepage lake, with groundwater as a main external source of phosphorus. Twelve groundwater samples from the vicinity of the lake were high in phosphate (0.4 to 11 mg l–1, mean value 2.57 mg l–1 PO4-P), both within the riparian zone and in two shallow wells located upstreams the lake in the nearby village. Phosphorus sorption capacity of four sand samples measured with the Langmuir isotherm method was low (7.3 to 121,1 mg kg–1 PO4-P), with the lowest values found within the riparian zone. It is suggested that the phosphorus originates from garden fertilizers and other human sources, and that the low absorption capacity of the soils is caused by the leaching of calcium from the watershed, a process which started some 3000 years ago. Riparian zone itself has almost no retention capacity, and processes within it (e.g., redox-related) have only secondary importance for the transport of phosphorus to the lake. 相似文献
993.
Wenjia Lou Hsiu-Chi Ting Christian A. Reynolds Yulia Y. Tyurina Vladimir A. Tyurin Yiran Li Jiajia Ji Wenxi Yu Zhuqing Liang Detcho A. Stoyanovsky Tamil S. Anthonymuthu Michael A. Frasso Peter Wipf Joel S. Greenberger Hülya Bayır Valerian E. Kagan Miriam L. Greenberg 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2018,1863(10):1354-1368
Cardiolipin (CL) is a unique phospholipid localized almost exclusively within the mitochondrial membranes where it is synthesized. Newly synthesized CL undergoes acyl remodeling to produce CL species enriched with unsaturated acyl groups. Cld1 is the only identified CL-specific phospholipase in yeast and is required to initiate the CL remodeling pathway. In higher eukaryotes, peroxidation of CL, yielding CLOX, has been implicated in the cellular signaling events that initiate apoptosis. CLOX can undergo enzymatic hydrolysis, resulting in the release of lipid mediators with signaling properties. Our previous findings suggested that CLD1 expression is upregulated in response to oxidative stress, and that one of the physiological roles of CL remodeling is to remove peroxidized CL. To exploit the powerful yeast model to study functions of CLD1 in CL peroxidation, we expressed the H. brasiliensis Δ12-desaturase gene in yeast, which then synthesized poly unsaturated fatty acids(PUFAs) that are incorporated into CL species. Using LC-MS based redox phospholipidomics, we identified and quantified the molecular species of CL and other phospholipids in cld1Δ vs. WT cells. Loss of CLD1 led to a dramatic decrease in chronological lifespan, mitochondrial membrane potential, and respiratory capacity; it also resulted in increased levels of mono-hydroperoxy-CLs, particularly among the highly unsaturated CL species, including tetralinoleoyl-CL. In addition, purified Cld1 exhibited a higher affinity for CLOX, and treatment of cells with H2O2 increased CLD1 expression in the logarithmic growth phase. These data suggest that CLD1 expression is required to mitigate oxidative stress. The findings from this study contribute to our overall understanding of CL remodeling and its role in mitigating oxidative stress. 相似文献
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996.
Sergey A. Adonin Lyubov A. Frolova Maxim N. Sokolov Gennady V. Shilov Denis V. Korchagin Vladimir P. Fedin Sergey M. Aldoshin Keith J. Stevenson Pavel A. Troshin 《Liver Transplantation》2018,8(6)
Using bromoantimonate (V) (N‐EtPy)[SbBr6] as an example, it is demonstrated that ABX6 compounds can form perovskite‐like 3D crystalline frameworks with short interhalide contacts, enabling advanced optoelectronic characteristics of these materials. The designed compound shows an impressive performance in planar junction solar cells delivering external quantum efficiency of ≈80% and power conversion efficiency of ≈4%, thus being comparable with the conventional perovskite material MAPbBr3. The discovery of the first perovskite‐like compound ABX6 exhibiting good photovoltaic performance opens wide opportunities for rational design of novel perovskite‐like semiconductor materials for advanced electronic and photovoltaic applications. 相似文献
997.
Kalenov Sergei V. Gordienko Mariia G. Murzina Ekaterina D. Poberezhniy Daniil Y. Baurin Dmitry V. Suzina Natalia E. Morozov Alexander N. Yakubovich Liubov M. Belov Alexey A. Panfilov Victor I. Yarovaya Oksana V. Il’in Michail M. Sorokin Vladimir V. Skladnev Dmitry A. 《Extremophiles : life under extreme conditions》2018,22(3):511-523
Extremophiles - Spray drying is appropriate for the preservation of halophilic microorganisms due to the nature of these microorganisms, as they survive in adverse environmental conditions by being... 相似文献
998.
Helen Louise May-Simera Qin Wan Balendu Shekhar Jha Juliet Hartford Vladimir Khristov Roba Dejene Justin Chang Sarita Patnaik Quanlong Lu Poulomi Banerjee Jason Silver Christine Insinna-Kettenhofen Dishita Patel Mostafa Lotfi May Malicdan Nathan Hotaling Arvydas Maminishkis Rupa Sridharan Kapil Bharti 《Cell reports》2018,22(1):189-205
999.
Guilherme S. De Lucca Felipe A. P. Barros J. Vladimir Oliveira Jacir Dal Magro Elaine M. Lucas 《Wetlands Ecology and Management》2018,26(3):285-297
Environmental pollution caused by the disposal of chemicals or toxins into the environment represent a great threat to amphibians. In this study, it was evaluated which environmental factors of ponds under the influence of coal-mining influence the composition of anuran species. For this purpose, anuran samples were performed in ponds in coal extraction areas in southern Brazil. Physical and chemical characteristics of water, sediment and structural characteristics of the ponds were determined. The content of copper in the sediments of the ponds was the main variable to explain the composition of pond species. Besides copper, it is evident the relevance of number of vegetation strata at pond border and pond area on the composition of anurans. It is shown that the composition of species in ponds under the influence of mineral coal mining activity may be a result of historical perturbations, remaining only the most tolerant towards colonization. From the results obtained in this work it can be suggested that there is a synergistic interaction between environmental factors and the coal mining effects on the anurans fauna of impacted ponds. Thus, efforts should be directed to elucidate the effects of pollutants exposure levels on the species, the understanding of sub-lethal and lethal effects of each pollutant on each species, as well as how local populations can be maintained through recruiting rates of larvae and anurans of the impacted ponds. 相似文献
1000.
Valery Akparov Vladimir Timofeev Ilyas Khaliullin Vytas Švedas Inna Kuranova 《Journal of biomolecular structure & dynamics》2018,36(4):956-965
Carboxypeptidase B (EC 3.4.17.2) (CPB) is commonly used in the industrial insulin production and as a template for drug design. However, its ability to discriminate substrates with hydrophobic, hydrophilic, and charged side chains is not well understood. We report structure of CPB complex with a transition state analog N-sulfamoyl-L-phenylalanine solved at 1.74Å. The study provided an insight into structural basis of CPB substrate specificity. Ligand binding is affected by structure-depended conformational changes of Asp255 in S1’-subsite, interactions with Asn144 and Arg145 in C-terminal binding subsite, and Glu270 in the catalytic center. Side chain of the non-specific substrate analog SPhe in comparison with that of specific substrate analog SArg (reported earlier) not only loses favorable electrostatic interactions and two hydrogen bonds with Asp255 and three fixed water molecules, but is forced to be in the unfavorable hydrophilic environment. Thus, Ser207, Gly253, Tyr248, and Asp255 residues play major role in the substrate recognition by S1’-subsite. 相似文献