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1.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bolsunovsky A., Zotina T., Bondareva L.
Заглавие : Accumulation and release of 241Am by a macrophyte of the Yenisei River (Elodea canadensis)
Место публикации : Journal of Environmental Radioactivity. - 2005. - Vol. 81, Is. 1. - С. 33-46. - ISSN 0265931X (ISSN) , DOI 10.1016/j.jenvrad.2004.10.012
Ключевые слова (''Своб.индексиров.''): 241am--accumulation--laboratory experiments--release--submerged plant elodea canadensis--yenisei river--activation analysis--biomass--concentration (process)--effluents--plutonium--rivers--aquatic plants--elodea plant--macrophytes--radioactive contamination--transuranium elements--americium 241--river water--americium--americium nitrate--bioaccumulation--biological uptake--macrophyte--pollutant source--radioactive pollution--river water--submerged vegetation--article--biomass--concentration (parameters)--environmental factor--fractionation--laboratory--macrophyte--radioactivity--river--sampling--adsorption--chemistry--hydrocharitaceae--methodology--physiology--plant--radiation exposure--radiation monitoring--russian federation--sediment--soil pollutant--time--tissue distribution--water pollutant--eastern hemisphere--eurasia--russian federation--world--yenisei river--elodea canadensis--adsorption--americium--biomass--chemical fractionation--geologic sediments--hydrocharitaceae--plant shoots--radiation monitoring--rivers--russia--soil pollutants, radioactive--time factors--tissue distribution--water pollutants, radioactive
Аннотация: The source of radioactive contamination of the Yenisei River floodplain, including contamination with transuranic elements, is the Mining-and-Chemical Combine of the Russian Ministry of Atomic Energy, which has for many years been producing weapons-grade plutonium. Transuranic elements have been detected not only in the soil and sediment of the river but also in the biomass of aquatic plants. This work is an investigation of accumulation and release of 241Am by a submerged macrophyte of the Yenisei River (Elodea canadensis) in laboratory experiments. In 2000-2003, laboratory experiments were carried out with biomass of E. canadensis Mich. and filtered river water. The samples were collected from the Yenisei River upstream of the discharge of the Combine's radioactive effluent. The experiments showed that 241Am is accumulated by Elodea biomass: the activity concentration of 241Am can reach 3280 В± 240 Bq/g, with the concentration factor for 241Am 16 600 В± 2200 l/kg. Results of chemical fractionation have proved that in the course of 241Am accumulation by Elodea biomass, 241Am tightly bound to biomass increases from 11% to 27% of the total 241Am in the biomass. Release of 241Am from the decaying Elodea biomass has been evaluated experimentally. By the end of the experiment (lasting up to 127 days), the Elodea plants had lost up to 65% of their initial 241Am activity and the rate of 241Am release into the water environment reached 23 Bq/day. В© 2004 Elsevier Ltd. All rights reserved.
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2.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bolsunovskij A.Ya., Ermakov A.I., Burger M., Degermendzhy A.G., Sobolev A.I.
Заглавие : Accumulation of artificial radionuclides by the Yenisei river aquatic plants in the area affected by the activity of the Mining-and-Chemical Combine
Место публикации : Radiatsionnaya Biologiya. Radioekologiya. - 2002. - Vol. 42, Is. 2. - С. 194-199. - ISSN 08698031 (ISSN)
Ключевые слова (''Своб.индексиров.''): contamination--ecosystems--environmental impact--gamma ray spectrometers--radioisotopes--river pollution--radioecological concentration--radioisotope accumulation--the yenisei river--ecology--plutonium--radioisotope--strontium--article--chemical industry--chemistry--comparative study--gamma spectrometry--industrial waste--mining--nuclear reactor--plant--radiochemistry--russian federation--water pollutant--chemical industry--industrial waste--mining--nuclear reactors--plants--plutonium--radiochemistry--radioisotopes--siberia--spectrometry, gamma--strontium radioisotopes--water pollutants, radioactive
Аннотация: The aim of the paper is to investigate accumulation of artificial radionuclides by the Yenisei river aquatic plants collected in the area affected by the activity of the Mining-and-Chemical Combine (Zheleznogorsk) from 1997 to 2000. The samples of aquatic plants were of four species: Potamogeton lucens, Fontinalis antipyretica, Elodea canadensis, and Ceratophyllum demersum. The gamma-spectrometric analysis of the samples of aquatic plants for artificial radionuclides revealed a wide spectrum of radionuclides. Radionuclides of activation origin were found in the aquatic plants taken both near the Combine and 200 km down of it. The radiochemical analysis of aquatic plants revealed strontium and plutonium isotopes. Among the aquatic plants, the highest concentration factors for the principal radionuclides were recorded in Fontinalis antipyretica (water moss).
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3.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Eremeeva, Elena V., Vysotski, Eugene S.
Заглавие : Bioluminescent and biochemical properties of Cys-free Ca2+-regulated photoproteins obelin and aequorin
Колич.характеристики :9 с
Коллективы : Russian Academy of Sciences [03562016-0712, 0356-2015-0103]; RFBR [17-04-00764]
Место публикации : J. Photochem. Photobiol. B-Biol.: ELSEVIER SCIENCE SA, 2017. - Vol. 174. - С. 97-105. - ISSN 1011-1344, DOI 10.1016/j.jphotobio1.2017.07.021
Примечания : Cited References:54. - This work was supported by the state budget allocated to the fundamental research at the Russian Academy of Sciences (projects 03562016-0712 and 0356-2015-0103) and the RFBR grant 17-04-00764.
Предметные рубрики: SEQUENCE-ANALYSIS
APO-OBELIN
INTRINSIC FLUORESCENCE
COELENTERAZINE
Ключевые слова (''Своб.индексиров.''): bioluminescence--coelenterazine--photoprotein--coelenteramide--cysteine--serine
Аннотация: Bioluminescence of a variety of marine coelenterates is determined by Ca2+-regulated photoproteins. A strong interest in these proteins is for their wide analytical potential as intracellular calcium indicators and labels for in vitro binding assays. The presently known hydromedusan Ca2+-regulated photoproteins contain three (aequorin and clytin) or five (obelin and mitrocomin) cysteine residues with one of them strictly conserved. We have constructed Cys-free aequorin and obelin by substitution of all cysteines to serine residues. Such mutants should be of interest for researchers by the possibility to avoid the incubation with dithiothreitol (or p-mercaptoethanol) required for producing an active photoprotein that is important for some prospective analytical assays in which the photoprotein is genetically fused with a target protein sensitive to the reducing agents. Cys-free mutants were expressed in Escherichia coil, purified, and characterized regarding the efficiency of photoprotein complex formation, functional activity, and conformational stability. The replacement of cysteine residues has been demonstrated to affect different properties of aequorin and obelin. Cys-free aequorin displays a two-fold lower specific bioluminescence activity but preserves similar activation properties and light emission kinetics compared to the wild -type aequorin. In contrast, Cys-free obelin retains only 10% of the bioluminescence activity of wild-type obelin as well as binding coelenterazine and forming active photoprotein much less effectively. In addition, the substitution of Cys residues drastically changes the bioluminescence kinetics of obelin completely eliminating a "fast" component from the light signal decay curve. At the same time, the replacement of Cys residues increases conformational flexibility of both aequorin and obelin molecules, but again, the effect is more prominent in the case of obelin. The values of thermal midpoints of unfolding (Tm) were determined to be 53.3 0.2 and 44.6 0.4 C for aequorin and Cys-free aequorin, and 49.1 0.1 and 28.8 0.3 C for obelin and Cys-free obelin, respectively. Thus, so far only Cys-free aequorin is suitable as a partner for fusing with a tag sensitive to reducing agents since the aequorin mutant preserves almost 50% of the bioluminescent activity and can be produced with a substantial yield.
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4.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Eremeeva E. V., Vysotski E. S.
Заглавие : Bioluminescent and biochemical properties of Cys-free Ca2+-regulated photoproteins obelin and aequorin
Место публикации : J. Photochem. Photobiol. B Biol.: Elsevier B.V., 2017. - Vol. 174. - С. 97-105. - ISSN 10111344 (ISSN) , DOI 10.1016/j.jphotobiol.2017.07.021
Ключевые слова (''Своб.индексиров.''): bioluminescence--coelenteramide--coelenterazine--cysteine--photoprotein--serine
Аннотация: Bioluminescence of a variety of marine coelenterates is determined by Ca2+-regulated photoproteins. A strong interest in these proteins is for their wide analytical potential as intracellular calcium indicators and labels for in vitro binding assays. The presently known hydromedusan Ca2+-regulated photoproteins contain three (aequorin and clytin) or five (obelin and mitrocomin) cysteine residues with one of them strictly conserved. We have constructed Cys-free aequorin and obelin by substitution of all cysteines to serine residues. Such mutants should be of interest for researchers by the possibility to avoid the incubation with dithiothreitol (or ?-mercaptoethanol) required for producing an active photoprotein that is important for some prospective analytical assays in which the photoprotein is genetically fused with a target protein sensitive to the reducing agents. Cys-free mutants were expressed in Escherichia coli, purified, and characterized regarding the efficiency of photoprotein complex formation, functional activity, and conformational stability. The replacement of cysteine residues has been demonstrated to affect different properties of aequorin and obelin. Cys-free aequorin displays a two-fold lower specific bioluminescence activity but preserves similar activation properties and light emission kinetics compared to the wild-type aequorin. In contrast, Cys-free obelin retains only ~ 10% of the bioluminescence activity of wild-type obelin as well as binding coelenterazine and forming active photoprotein much less effectively. In addition, the substitution of Cys residues drastically changes the bioluminescence kinetics of obelin completely eliminating a “fast” component from the light signal decay curve. At the same time, the replacement of Cys residues increases conformational flexibility of both aequorin and obelin molecules, but again, the effect is more prominent in the case of obelin. The values of thermal midpoints of unfolding (Tm) were determined to be 53.3 ± 0.2 and 44.6 ± 0.4 °C for aequorin and Cys-free aequorin, and 49.1 ± 0.1 and 28.8 ± 0.3 °C for obelin and Cys-free obelin, respectively. Thus, so far only Cys-free aequorin is suitable as a partner for fusing with a tag sensitive to reducing agents since the aequorin mutant preserves almost 50% of the bioluminescent activity and can be produced with a substantial yield. © 2017 Elsevier B.V.
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5.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Malikova N.P., Burakova L.P., Markova S.V., Vysotski E.S.
Заглавие : Characterization of hydromedusan Ca2+-regulated photoproteins as a tool for measurement of Ca(2+)concentration
Колич.характеристики :12 с
Коллективы : RFBR [12-04-00131]; Government of the Russian Federation [11.G34.31.0058]; Russian Academy of Sciences; Russian Federation "Leading Science School" [3951.2012.4]
Место публикации : Anal. Bioanal. Chem.: SPRINGER HEIDELBERG, 2014. - Vol. 406, Is. 23. - С. 5715-5726. - ISSN 1618-2642, DOI 10.1007/s00216-014-7986-2. - ISSN 1618-2650
Примечания : Cited References: 67. - This work was supported by RFBR grant 12-04-00131, by the programs of the Government of the Russian Federation "Measures to Attract Leading Scientists to Russian Educational Institutions" (grant 11.G34.31.0058) and "Molecular and Cellular Biology" of the Russian Academy of Sciences, and the grant from the President of the Russian Federation "Leading Science School" (3951.2012.4).
Предметные рубрики: LIGHT-SENSITIVE PHOTOPROTEIN
CTENOPHORE BEROE ABYSSICOLA
GREEN-FLUORESCENT PROTEIN
INTRACELLULAR CALCIUM
SEQUENCE-ANALYSIS
CA-2+-ACTIVATED PHOTOPROTEIN
CA2+-BINDING PHOTOPROTEIN
SEMISYNTHETIC AEQUORINS
LUMINESCENT PROTEIN
RECOMBINANT OBELIN
Ключевые слова (''Своб.индексиров.''): calcium--coelenterazine--aequorin--obelin--clytin--mitrocomin
Аннотация: Calcium ion is a ubiquitous intracellular messenger, performing this function in many eukaryotic cells. To understand calcium regulation mechanisms and how disturbances of these mechanisms are associated with disease states, it is necessary to measure calcium inside cells. Ca2+-regulated photoproteins have been successfully used for this purpose for many years. Here we report the results of comparative studies on the properties of recombinant aequorin from Aequorea victoria, recombinant obelins from Obelia geniculata and Obelia longissima, recombinant mitrocomin from Mitrocoma cellularia, and recombinant clytin from Clytia gregaria as intracellular calcium indicators in a set of identical in vitro and in vivo experiments. Although photoproteins reveal a high degree of identity of amino acid sequences and spatial structures, and, apparently, have a common mechanism for the bioluminescence reaction, they were found to differ in the Ca2+ concentration detection limit, the sensitivity of bioluminescence to Mg2+, and the rates of the rise of the luminescence signal with a sudden change of Ca2+ concentration. In addition, the bioluminescence activities of Chinese hamster ovary cells expressing wild-type photoproteins also differed. The light signals of cells expressing mitrocomin, for example, slightly exceeded the background, suggesting that mitrocomin may be hardly used to detect intracellular Ca2+ without modifications improving its properties. On the basis of experiments on the activation of endogenous P2Y(2) receptor in Chinese hamster ovary cells by ATP, we suggest that wild-type aequorin and obelin from O. longissima are more suitable for calcium detection in cytoplasm, whereas clytin and obelin from O. geniculata can be used for calcium measurement in cell compartments with high Ca2+ concentration.
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6.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Malikova N.P., Burakova L.P., Markova S.V., Vysotski E.S.
Заглавие : Characterization of hydromedusan Ca2+-regulated photoproteins as a tool for measurement of Ca2+concentration
Место публикации :. - 2014. - ISSN 16182642 (ISSN) , DOI 10.1007/s00216-014-7986-2
Ключевые слова (''Своб.индексиров.''): aequorin--calcium--clytin--coelenterazine--mitrocomin--obelin
Аннотация: Calcium ion is a ubiquitous intracellular messenger, performing this function in many eukaryotic cells. To understand calcium regulation mechanisms and how disturbances of these mechanisms are associated with disease states, it is necessary to measure calcium inside cells. Ca2+-regulated photoproteins have been successfully used for this purpose for many years. Here we report the results of comparative studies on the properties of recombinant aequorin from Aequorea victoria, recombinant obelins from Obelia geniculata and Obelia longissima, recombinant mitrocomin from Mitrocoma cellularia, and recombinant clytin from Clytia gregaria as intracellular calcium indicators in a set of identical in vitro and in vivo experiments. Although photoproteins reveal a high degree of identity of amino acid sequences and spatial structures, and, apparently, have a common mechanism for the bioluminescence reaction, they were found to differ in the Ca2+ concentration detection limit, the sensitivity of bioluminescence to Mg2+, and the rates of the rise of the luminescence signal with a sudden change of Ca2+ concentration. In addition, the bioluminescence activities of Chinese hamster ovary cells expressing wild-type photoproteins also differed. The light signals of cells expressing mitrocomin, for example, slightly exceeded the background, suggesting that mitrocomin may be hardly used to detect intracellular Ca2+ without modifications improving its properties. On the basis of experiments on the activation of endogenous P2Y2 receptor in Chinese hamster ovary cells by ATP, we suggest that wild-type aequorin and obelin from O. longissima are more suitable for calcium detection in cytoplasm, whereas clytin and obelin from O. geniculata can be used for calcium measurement in cell compartments with high Ca2+ concentration. [Figure not available: see fulltext.] © 2014 Springer-Verlag Berlin Heidelberg.
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7.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Tyulkova N.A., Sandalova T.P.
Заглавие : Comparative study of temperature effects on bacterial luciferases
Колич.характеристики :10 с
Место публикации : Biochem.-Moscow: PLENUM PUBL CORP, 1996. - Vol. 61, Is. 2. - P205-214. - ISSN 0006-2979
Примечания : Cited References: 23
Предметные рубрики: BIOLUMINESCENCE
Ключевые слова (''Своб.индексиров.''): bacterial luciferase--temperature--activation energy
Аннотация: Effects of temperature on bioluminescent patterns of luciferases from luminescent bacteria Vibrio harveyi, Vibrio fischeri, Photobacterium leiognathi, and Photobacterium phosphoreum were studied. The highest luminescence level was observed at 15-25 degrees C for the luciferase from P. phosphoreum, at 20-30 degrees C for the V. fischeri and P. leiognathi enzymes, and at 30-37 degrees C for the enzyme from V. harveyi. All the luciferases were significantly stabilized at increased salt concentrations, at low pH values, or in the presence of dithiothreitol (DTT) and EDTA. The addition of DTT and EDTA affected the reversible stage of enzyme inactivation, while salts reduced the rate of the irreversible stage. A peak corresponding to aggregated protein was detected by gel chromatography of irreversibly inactivated luciferase. Activation energies were calculated for each luciferase in bioluminescent reactions with decanal, dodecanal, tetradecanal, and without aldehydes. The activation energy of the reaction with tetradecanal was much lower than those with the other aldehydes. The temperature dependence of the lifetime of the long-lived reaction intermediate showed that in the 10-30 degrees C interval all the luciferases, except for the enzyme from V. harveyi, have only one active form.
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8.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Selivanova M.A., Rozhko T.V., Devyatlovskaya A.N., Kudryasheva N.S.
Заглавие : Comparison of chronic low-dose effects of alpha- and beta-emitting radionuclides on marine bacteria
Место публикации : Cent. Eur. J. Biol. - 2014. - Vol. 9, Is. 10. - С. 951-959. - ISSN 16443632 (ISSN) , DOI 10.2478/s11535-014-0331-0
Ключевые слова (''Своб.индексиров.''): am-241--hormesis--luminous bacteria--peroxides--radiotoxicity--tritium
Аннотация: Effects of Americium-241 (241Am), alpha-emitting radionuclide of high specific radioactivity, and tritium (3H), beta-emitting radionuclide, on luminous bacteria Photobacterium phosphoreum were compared. Bioluminescence intensity served as a marker of bacterial physiological activity. Three successive stages in the bioluminescence response to 241Am and 3H were found under conditions of lowdose irradiation: (1) absence of effects, (2) activation, and (3) inhibition. They were interpreted in terms of bacterial response to stressfactor as stress recognition, adaptive response/syndrome, and suppression of physiological function (i.e. radiation toxicity). Times of bioluminescence activation (TBA) and inhibition (TBI) were suggested as parameters to characterize hormesis and toxic stages in a course of chronic low-dose irradiation of the microorganisms. Values of TBA and TBI of 241Am were shorter than those of 3H, revealing higher impact of alpha-irradiation (as compared to beta-irradiation) under comparable radiation doses. Increases of peroxide concentration and NADH oxidation rates in 241Am aquatic solutions were demonstrated; these were not found in tritiated water. The results reveal a biological role of reactive oxygen species generated in water solutions as secondary products of the radioactive decay. The study provides a scientific basis for elaboration of bioluminescence-based assay to monitor radiotoxicity of alpha- and beta-emitting radionuclides in aquatic solutions. © 2014 Versita Warsaw and Springer-Verlag Wien.
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9.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kolesnik, Olga V., Rozhko, Tatiana V., Lapina, Maria A., Solovyev, Vladislav S., Sachkova, Anna S., Kudryasheva, Nadezhda S.
Заглавие : Development of Cellular and Enzymatic Bioluminescent Assay Systems to Study Low-Dose Effects of Thorium
Колич.характеристики :13 с
Место публикации : Bioengineering-Basel: MDPI, 2021. - Vol. 8, Is. 12. - Ст.194. - ISSN 2306-5354(eISSN), DOI 10.3390/bioengineering8120194
Примечания : Cited References:77
Аннотация: Thorium is one of the most widespread radioactive elements in natural ecosystems, along with uranium, it is the most important source of nuclear energy. However, the effects of thorium on living organisms have not been thoroughly studied. Marine luminescent bacteria and their enzymes are optimal bioassays for studying low-dose thorium exposures. Luminescent bioassays provide a quantitative measure of toxicity and are characterized by high rates, sensitivity, and simplicity. It is known that the metabolic activity of bacteria is associated with the production of reactive oxygen species (ROS). We studied the effects of thorium-232 (10(-11)-10(-3) M) on Photobacterium phosphoreum and bacterial enzymatic reactions; kinetics of bacterial bioluminescence and ROS content were investigated in both systems. Bioluminescence activation was revealed under low-dose exposures (0.1 Gy) and discussed in terms of "radiation hormesis". The activation was accompanied by an intensification of the oxidation of a low-molecular reducer, NADH, during the enzymatic processes. Negative correlations were found between the intensity of bioluminescence and the content of ROS in bacteria and enzyme systems; an active role of ROS in the low-dose activation by thorium was discussed. The results contribute to radioecological potential of bioluminescence techniques adapted to study low-intensity radioactive exposures.
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10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Navdaev A..., Subramanian H..., Petunin A..., Clemetson K.J., Gambaryan S..., Walter U...
Заглавие : Echicetin Coated Polystyrene Beads: A Novel Tool to Investigate GPIb-Specific Platelet Activation and Aggregation
Колич.характеристики :10 с
Коллективы : DFG [SFB688, TP A2, GA 1561/1-1]; BMBF [01EO1003]; Rudolf-Marx-stipendium; Gesellschaft fur Thrombose- und Hamostaseforschung (GTH)
Место публикации : PLoS One: PUBLIC LIBRARY SCIENCE, 2014. - Vol. 9, Is. 4. - Ст.e93569. - ISSN 1932-6203, DOI 10.1371/journal.pone.0093569
Примечания : Cited References: 36. - This study was supported by DFG (SFB688, TP A2, and grant GA 1561/1-1), BMBF (01EO1003) and Rudolf-Marx-stipendium 2014 funded by Gesellschaft fur Thrombose- und Hamostaseforschung (GTH). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Предметные рубрики: VON-WILLEBRAND-FACTOR
GLYCOPROTEIN IB-ALPHA
DEPENDENT PROTEIN-KINASE
SIGNALING PATHWAY
THROMBUS FORMATION
INTEGRIN ALPHA(IIB)BETA(3)
VONWILLEBRAND-FACTOR
HIGH-SHEAR
IGM-KAPPA
RISTOCETIN
Аннотация: von Willebrand factor/ristocetin (vWF/R) induces GPIb-dependent platelet agglutination and activation of alpha IIb beta 3 integrin, which also binds vWF. These conditions make it difficult to investigate GPIb-specific signaling pathways in washed platelets. Here, we investigated the specific mechanisms of GPIb signaling using echicetin-coated polystyrene beads, which specifically activate GPIb. We compared platelet activation induced by echicetin beads to vWF/R. Human platelets were stimulated with polystyrene beads coated with increasing amounts of echicetin and platelet activation by echicetin beads was then investigated to reveal GPIb specific signaling. Echicetin beads induced alpha IIb beta 3-dependent aggregation of washed platelets, while under the same conditions vWF/R treatment led only to alpha IIb beta 3-independent platelet agglutination. The average distance between the echicetin molecules on the polystyrene beads must be less than 7 nm for full platelet activation, while the total amount of echicetin used for activation is not critical. Echicetin beads induced strong phosphorylation of several proteins including p38, ERK and PKB. Synergistic signaling via P2Y(12) and thromboxane receptor through secreted ADP and TxA(2), respectively, were important for echicetin bead triggered platelet activation. Activation of PKG by the NO/sGC/cGMP pathway inhibited echicetin bead-induced platelet aggregation. Echicetin-coated beads are powerful and reliable tools to study signaling in human platelets activated solely via GPIb and GPIb-triggered pathways.
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11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Rodionova N.S., Petushkov V.N.
Заглавие : Effect of different salts and detergents on luciferin-luciferase luminescence of the enchytraeid Fridericia heliota
Место публикации : Journal of Photochemistry and Photobiology B: Biology. - 2006. - Vol. 83, Is. 2. - С. 123-128. - ISSN 10111344 (ISSN) , DOI 10.1016/j.jphotobiol.2005.12.014
Ключевые слова (''Своб.индексиров.''): atp--bioluminescence--earthworms--ions--luciferin-luciferase systems--triton x-100--adenosine triphosphate--anion--bromine--calcium ion--carbonic acid--cation--chloride--chromium derivative--detergent--dodecyl sulfate sodium--inorganic salt--iodine--iron derivative--luciferase--luciferin--magnesium ion--manganese--nitrate--phosphate--sulfate--sulfite--triton x 100--annelid worm--article--bioluminescence--concentration (parameters)--controlled study--enzyme activation--enzyme activity--enzyme inhibition--enzyme mechanism--in vitro study--nonhuman--priority journal--qualitative analysis--quantitative analysis--adenosine triphosphate--animals--cations, divalent--cations, monovalent--detergents--firefly luciferin--kinetics--luciferases--luminescence--metals--oligochaeta--photobiology--salts--annelida--clitellata--earthworms (sp.)--enchytraeidae--fridericia heliota--oligochaeta (metazoa)--pheretima sieboldi
Аннотация: The study addresses the effect produced by different inorganic salts and detergents (SDS, Triton X-100, the Tween series) on the ATP-dependent bioluminescent reaction catalyzed by the luciferase of the new earthworm species Fridericia heliota (Annelida: Clitellata: Oligochaeta: Enchytraeidae). It has been shown that the effect of divalent metal salts on luminescence is determined by the action of cations. Three of them - Mg2+, Mn2+ and Ca2+ - can stimulate luciferase activity at concentrations varying within a wide range, and Mn2+ can act as a 100%-effective substitute for Mg2+ in F. heliota luminescence reaction in vitro. The inhibitory effect of monovalent metal salts on luminescence is largely determined by the action of the anion part of the molecule. The effectiveness of the inhibitory effect of anions increases in the following order: {Mathematical expression}. Of the sodium salts, dodecyl sulfate, which is an anionic detergent, produces the strongest inhibitory effect on luciferase. On the contrary, nonionic detergents produce a stimulatory effect on the F. heliota luciferase. The action of the most effective of them - Triton X-100 - is determined by its ability to reduce the actual concentration of lipid inhibitors in the reaction mixture. В© 2006 Elsevier B.V. All rights reserved.
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12.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kudryasheva, N. S., Rozhko, T. V.
Заглавие : Effect of low-dose ionizing radiation on luminous marine bacteria: radiation hormesis and toxicity
Колич.характеристики :10 с
Коллективы : Russian Foundation for Basic Research [13-04-01305a]; Program "Molecular and Cellular Biology" of the Russian Academy of Sciences [VI 57.1.1]; Russian Science Foundation [14-14-00076]
Место публикации : J. Environ. Radioact.: ELSEVIER SCI LTD, 2015. - Vol. 142. - С. 68-77. - ISSN 0265-931X, DOI 10.1016/j.jenvrad.2015.01.012. - ISSN 1879-1700(eISSN)
Примечания : Cited References:131. - This work was supported by the Russian Foundation for Basic Research, Grant No.13-04-01305a, the Program "Molecular and Cellular Biology" of the Russian Academy of Sciences, project VI 57.1.1. The part of the work (review of effects of americium-241) was supported by the Russian Science Foundation, Grant No. 14-14-00076.
Предметные рубрики: RECOMBINANT LUMINESCENT MICROORGANISMS
PHOTOBACTERIUM-LEIOGNATHI
Ключевые слова (''Своб.индексиров.''): marine bacteria--low-dose effects--radiation hormesis--radiotoxicity--reactive oxygen species
Аннотация: The paper summarizes studies of effects of alpha- and beta-emitting radionuclides (americium-241, uranium-235+238, and tritium) on marine microorganisms under conditions of chronic low-dose irradiation in aqueous media. Luminous marine bacteria were chosen as an example of these microorganisms; bioluminescent intensity was used as a tested physiological parameter. Non-linear dose-effect dependence was demonstrated. Three successive stages in the bioluminescent response to americium-241 and tritium were found: 1 - absence of effects (stress recognition), 2 - activation (adaptive response), and 3 - inhibition (suppression of physiological function, i.e. radiation toxicity). The effects were attributed to radiation hormesis phenomenon. Biological role of reactive oxygen species, secondary products of the radioactive decay, is discussed. The study suggests an approach to evaluation of non-toxic and toxic stages under conditions of chronic radioactive exposure. (C) 2015 Elsevier Ltd. All rights reserved.
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13.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Rozhko T.V., Kudryasheva N.S., Kuznetsov A.M., Vydryakova G.A., Bondareva L.G., Bolsunovsky A.Y.
Заглавие : Effect of low-level alpha-radiation on bioluminescent assay systems of various complexity
Место публикации : Photochem. Photobiol. Sci.: ROYAL SOC CHEMISTRY, 2007. - Vol. 6, Is. 1. - С. 67-70. - 4. - ISSN 1474-905X, DOI 10.1039/b614162p
Примечания : Cited References: 52
Предметные рубрики: LOW-DOSE RADIATION
IRRADIATION
TOXICITY
QUINONES
HORMESIS
PHENOLS
Аннотация: This study addresses the effects of low-level alpha-radiation on bioluminescent assay systems of different levels of organization: in vivo and in vitro. Three bioluminescent assay systems are used: intact bacteria, lyophilized bacteria, and bioluminescent system of coupled enzyme reactions. Solutions of Am-241(NO3)(3) are used as a source of alpha-radiation. It has been shown that activation processes predominate in all the three bioluminescent assay systems subjected to short-term exposure (20-55 h) and inhibition processes in the systems subjected to longer-term exposure to radiation. It has been found that these effects are caused by the radiation component of Am-241(3+) impact. The intensity of the Am-241(3+) effect on the bioluminescent assay systems has been shown to depend on the Am-241(3+) concentration, level of organization and integrity of the bioluminescent assay system. The bioluminescent assay systems in vivo have been found to be highly sensitive to Am-241(3+) (up to 10(-17) M).
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14.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : BONDAR V.S., TROFIMOV K.P., SANDALOV T.P., VYSOTSKII E.S.
Заглавие : EFFECT OF TEMPERATURE ON ACTIVITY AND STABILITY OF OBELIN
Место публикации : Biochem.-Moscow: PLENUM PUBL CORP, 1992. - Vol. 57, Is. 7. - С. 717-724. - 8. - ISSN 0006-2979
Примечания : Cited References: 15
Предметные рубрики: CA-2+
PHOTOPROTEINS
INDICATORS
Ключевые слова (''Своб.индексиров.''): photoproteins--obelin--activation energy--thermoinactivation--thermostability
Аннотация: The temperature dependence of bioluminescent activity of the Ca2+-activated photoprotein obelin from the hydroid polyp Obelia longissima and thermoinactivation of this protein at different concentrations of (NH4)2SO4 have been studied. The maximal intensity of luminescence of obelin was observed at 4-15-degrees-C. The activity of the photoprotein is completely stable to storage for 3 days at room temperature. Increasing the temperature to 40-degrees-C resulted in a 25-30% loss of enzyme activity in 1 h. The presence of ammonium sulfate during heating stabilizes the activity of obelin. Two breaks, at 11 +/- 3-degrees-C and 47 +/- 3-degrees-C, are observed in the Arrhenius plot of the first-order rate constant of the luminescence decay. The bioluminescent curves of obelin are biphasic in the temperature range 10-40-degrees-C. It is assumed that obelin may exist in two kinetically distinct conformers (active and inactive) whose ratio is temperature dependent.
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15.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gerasimova M.A., Kudryasheva N.S.
Заглавие : Effects of potassium halides on bacterial bioluminescence
Колич.характеристики :5 с
Место публикации : J. Photochem. Photobiol. B-Biol.: ELSEVIER SCIENCE SA, 2002. - Vol. 66, Is. 3. - P218-222. - ISSN 1011-1344, DOI 10.1016/S1011-1344(02)00240-3
Примечания : Cited References: 20
Предметные рубрики: COMPONENTS
SEWAGE
Ключевые слова (''Своб.индексиров.''): bioluminescence--halides--heavy atom--inhibition--activation
Аннотация: The effects of potassium halides KCl, KBr and KI on NADH:FMN-oxidoreductase-luciferase bioluminescent coupled enzyme system were studied. The influence of salt additions on bioluminescence intensity and bioluminescence light yield was investigated. The inhibition and activation parameters of the salts were calculated using their dependencies on concentration of the salts. The correlation between the inhibition of bioluminescence intensity and the halide mass was demonstrated: the inhibiting ability of the salts increases with the increase of atomic weight of the anions. The inhibition parameters increase and the activation parameters decrease, accordingly. (C) 2002 Elsevier Science B.V. All rights reserved.
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16.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Rozhko T. V., Nemtseva E. V., Gardt M. V., Raikov A. V., Lisitsa A. E., Badun G. A., Kudryasheva N. S.
Заглавие : Enzymatic responses to low-intensity radiation of tritium
Место публикации : Int. J. Mol. Sci.: MDPI AG, 2020. - Vol. 21, Is. 22. - Ст.8464. - С. 1-15. - ISSN 16616596 (ISSN), DOI 10.3390/ijms21228464
Аннотация: The present study considers a possible role of enzymatic reactions in the adaptive response of cells to the beta-emitting radionuclide tritium under conditions of low-dose exposures. Effects of tritiated water (HTO) on the reactions of bacterial luciferase and NAD(P)H:FMN-oxidoreductase, as well as a coupled system of these two reactions, were studied at radioactivity concentrations ? 200 MBq/L. Additionally, one of the simplest enzymatic reactions, photobiochemical proton transfer in Coelenteramide-containing Fluorescent Protein (CLM-FP), was also investigated. We found that HTO increased the activity of NAD(P)H:FMN-oxidoreductase at the initial stage of its reaction (by up to 230%); however, a rise of luciferase activity was moderate (20%). The CLM-FP samples did not show any increase in the rate of the photobiochemical proton transfer under the exposure to HTO. The responses of the enzyme systems were compared to the ‘hormetic’ response of luminous marine bacterial cells studied earlier. We conclude that (1) the oxidoreductase reaction contributes significantly to the activation of the coupled enzyme system and bacterial cells by tritium, and (2) an increase in the organization level of biological systems promotes the hormesis phenomenon. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.
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17.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Mogilnaya O. A., Ronzhin N. O., Bondar V. S.
Заглавие : Estimating levels of light emission and extracellular peroxidase activity of mycelium of luminous fungus Neonothopanus nambi treated with ?-glucosidase
Место публикации : Curr. Res. Environ. Appl. Mycol. J. Fungal: Beijing Academy of Agriculture and Forestry Sciences, Institute of Plant and Environment Protection, 2018. - Vol. 8, Is. 1. - С. 75-85. - ISSN 22292225 (ISSN) , DOI 10.5943/cream/8/1/6
Ключевые слова (''Своб.индексиров.''): basidiomycetes--cell wall--luminescence--polysaccharide sheath
Аннотация: The present study estimates the level of extracellular peroxidase activity and light emission intensity of mycelium of luminescent basidiomycete Neonothopanus nambi treated with ?-glucosidase. A hypothesis has been proposed that treatment with ?-glucosidase may trigger biochemical mechanisms of activation of ROS (primarily hydrogen peroxide) generation in N. nambi mycelium. The results obtained indicate that the enzyme causes partial disintegration of the slimy sheath of fungal hyphae and intracellular matrix, which leads to release of the extracellular peroxidases to the incubation medium. Mycelial cells treated with the enzyme reach the peak of their luminescence sooner. It has been assumed that partial loss of extracellular peroxidases, as important enzymes of antioxidant defense, may be compensated for by an increase in the level of light emission by the fungus. © 2018 Beijing Academy of Agriculture and Forestry Sciences.
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18.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kudryasheva N. S., Petrova A. S., Dementyev D. V., Bondar A. A.
Заглавие : Exposure of luminous marine bacteria to low-dose gamma-radiation
Место публикации : J. Environ. Radioact.: Elsevier Ltd, 2017. - Vol. 169-170. - С. 64-69. - ISSN 0265931X (ISSN) , DOI 10.1016/j.jenvrad.2017.01.002
Ключевые слова (''Своб.индексиров.''): bioassay--low-dose gamma-radiation--luminous marine bacteria--mutagenic effect--radiotoxicity--temperature dependence--bacteria--bioassay--bioluminescence--gamma rays--ionizing radiation--irradiation--phosphorescence--physiological models--radiation effects--temperature distribution--low dose--marine bacterium--mutagenic effect--radiotoxicity--temperature dependence--radiation--bacteria (microorganisms)--photobacterium phosphoreum
Аннотация: The study addresses biological effects of low-dose gamma-radiation. Radioactive 137Cs-containing particles were used as model sources of gamma-radiation. Luminous marine bacterium Photobacterium phosphoreum was used as a bioassay with the bioluminescent intensity as the physiological parameter tested. To investigate the sensitivity of the bacteria to the low-dose gamma-radiation exposure (?250 mGy), the irradiation conditions were varied as follows: bioluminescence intensity was measured at 5, 10, and 20°С for 175, 100, and 47 h, respectively, at different dose rates (up to 4100 ?Gy/h). There was no noticeable effect of gamma-radiation at 5 and 10°С, while the 20°С exposure revealed authentic bioluminescence inhibition. The 20°С results of gamma-radiation exposure were compared to those for low-dose alpha- and beta-radiation exposures studied previously under comparable experimental conditions. In contrast to ionizing radiation of alpha and beta types, gamma-emission did not initiate bacterial bioluminescence activation (adaptive response). As with alpha- and beta-radiation, gamma-emission did not demonstrate monotonic dose-effect dependencies; the bioluminescence inhibition efficiency was found to be related to the exposure time, while no dose rate dependence was found. The sequence analysis of 16S ribosomal RNA gene did not reveal a mutagenic effect of low-dose gamma radiation. The exposure time that caused 50% bioluminescence inhibition was suggested as a test parameter for radiotoxicity evaluation under conditions of chronic low-dose gamma irradiation. © 2017 Elsevier Ltd
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19.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Chen, Shu-Feng, Vysotski, Eugene S., Liu, Ya-Jun
Заглавие : H2O-Bridged Proton-Transfer Channel in Emitter Species Formation in Obelin Bioluminescence
Колич.характеристики :7 с
Коллективы : Program of Shanghai Institute of Technology [YJ2016-42]; National Natural Science Foundation of ChinaNational Natural Science Foundation of China (NSFC) [21973005, 21911530094]; Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR) [20-04-00085, 19-14-53004]
Место публикации : J. Phys. Chem. B: AMER CHEMICAL SOC, 2021. - Vol. 125, Is. 37. - С. 10452-10458. - ISSN 1520-6106, DOI 10.1021/acs.jpcb.1c03985. - ISSN 1520-5207(eISSN)
Примечания : Cited References:50. - This work was supported by the Program of Shanghai Institute of Technology (no. YJ2016-42), the National Natural Science Foundation of China (21973005 and 21911530094), and the Russian Foundation for Basic Research (20-04-00085 and 19-14-53004).
Предметные рубрики: CHEMILUMINESCENT DECOMPOSITION
FLUORESCENCE-SPECTRA
MECHANISM
QM/MM
Аннотация: Bioluminescence of a number of marine organisms is conditioned by Ca2+-regulated photoprotein (CaRP) with coelenterazine as the reaction substrate. The reaction product, coelenteramide, at the first singlet excited state (S-1) is the emitter of CaRP. The S-1-state coelenteramide is produced via the decomposition of coelenterazine dioxetanone. Experiments suggested that the neutral S-1-coelenteramide is the primary emitter species. This supposition contradicts with theoretical calculations showing that the anionic S-1-coelenteramide is a primary product of the decomposition of coelenterazine dioxetanone. In this study, applying molecular dynamic (MD) simulations and the hybrid quantum mechanics/molecular mechanics (QM/MM) method, we investigated a proton-transfer (PT) process taking place in CaRP obelin from Obelia longissima for emitter formation. Our calculations demonstrate a concerted PT process with a water molecule as a bridge between anionic S-1-coelenteramide and the nearest histidine residue. The low activation barrier as well as the strong hydrogen-bond network between the proton donor and the proton acceptor suggests a fast PT process comparable with that of the lifetime of excited anionic S-1-coelenteramide. The existence of the PT process eliminates the discrepancy between experimental and theoretical studies. The fast PT process at emitter formation can also take place in other CaRPs.
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20.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Chen S. -F., Vysotski E. S., Liu Y. -J.
Заглавие : H2O-Bridged Proton-Transfer Channel in Emitter Species Formation in Obelin Bioluminescence
Место публикации : J Phys Chem B: American Chemical Society, 2021. - Article in press. - ISSN 15206106 (ISSN), DOI 10.1021/acs.jpcb.1c03985
Аннотация: Bioluminescence of a number of marine organisms is conditioned by Ca2+-regulated photoprotein (CaRP) with coelenterazine as the reaction substrate. The reaction product, coelenteramide, at the first singlet excited state (S1) is the emitter of CaRP. The S1-state coelenteramide is produced via the decomposition of coelenterazine dioxetanone. Experiments suggested that the neutral S1-coelenteramide is the primary emitter species. This supposition contradicts with theoretical calculations showing that the anionic S1-coelenteramide is a primary product of the decomposition of coelenterazine dioxetanone. In this study, applying molecular dynamic (MD) simulations and the hybrid quantum mechanics/molecular mechanics (QM/MM) method, we investigated a proton-transfer (PT) process taking place in CaRP obelin from Obelia longissima for emitter formation. Our calculations demonstrate a concerted PT process with a water molecule as a bridge between anionic S1-coelenteramide and the nearest histidine residue. The low activation barrier as well as the strong hydrogen-bond network between the proton donor and the proton acceptor suggests a fast PT process comparable with that of the lifetime of excited anionic S1-coelenteramide. The existence of the PT process eliminates the discrepancy between experimental and theoretical studies. The fast PT process at emitter formation can also take place in other CaRPs. © 2021 American Chemical Society.
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