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1.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kovel, Ekaterina S., Kicheeva, Arina G., Vnukova, Natalia G., Churilov, Grigory N., Stepin, Evsei A., Kudryasheva, Nadezhda S.
Заглавие : Toxicity and Antioxidant Activity of Fullerenol C-60,C-70 with Low Number of Oxygen Substituents
Колич.характеристики :17 с
Коллективы : RFBRRussian Foundation for Basic Research (RFBR) [N18-29-19003]; RFBR, Krasnoyarsk Territory; Krasnoyarsk Regional Fund of Science [N20-44-243001]; Program of the Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing, Fundamental Study 2020-2025 (Russian Federation)
Место публикации : Int. J. Mol. Sci.: MDPI, 2021. - Vol. 22, Is. 12. - Ст.6382. - ISSN 1422-0067(eISSN), DOI 10.3390/ijms22126382
Примечания : Cited References:93. - This research was funded by RFBR, N18-29-19003; RFBR, Krasnoyarsk Territory and Krasnoyarsk Regional Fund of Science, N20-44-243001; and partly supported by the Program of the Federal Service for Surveillance on Consumer Rights Protection and HumanWellbeing, Fundamental Study 2020-2025 (Russian Federation).
Предметные рубрики: HUMIC SUBSTANCES
DETOXIFICATION PROCESSES
BIOLOGICAL-ACTIVITY
Аннотация: Fullerene is a nanosized carbon structure with potential drug delivery applications. We studied the bioeffects of a water-soluble fullerene derivative, fullerenol, with 10-12 oxygen groups (F10-12); its structure was characterized by IR and XPS spectroscopy. A bioluminescent enzyme system was used to study toxic and antioxidant effects of F10-12 at the enzymatic level. Antioxidant characteristics of F10-12 were revealed in model solutions of organic and inorganic oxidizers. Low-concentration activation of bioluminescence was validated statistically in oxidizer solutions. Toxic and antioxidant characteristics of F10-12 were compared to those of homologous fullerenols with a higher number of oxygen groups:F24-28 and F40-42. No simple dependency was found between the toxic/antioxidant characteristics and the number of oxygen groups on the fullerene's carbon cage. Lower toxicity and higher antioxidant activity of F24-28 were identified and presumptively attributed to its higher solubility. An active role of reactive oxygen species (ROS) in the bioeffects of F10-12 was demonstrated. Correlations between toxic/antioxidant characteristics of F10-12 and ROS content were evaluated. Toxic and antioxidant effects were related to the decrease in ROS content in the enzyme solutions. Our results reveal a complexity of ROS effects in the enzymatic assay system.
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2.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kovel E. S., Kicheeva A. G., Vnukova N. G., Churilov G. N., Stepin E. A., Kudryasheva N. S.
Заглавие : Toxicity and antioxidant activity of fullerenol c60,70 with low number of oxygen substituents
Место публикации : Int. J. Mol. Sci.: MDPI AG, 2021. - Vol. 22, Is. 12. - Ст.6382. - ISSN 16616596 (ISSN), DOI 10.3390/ijms22126382
Аннотация: Fullerene is a nanosized carbon structure with potential drug delivery applications. We studied the bioeffects of a water-soluble fullerene derivative, fullerenol, with 10-12 oxygen groups (F10-12); its structure was characterized by IR and XPS spectroscopy. A bioluminescent enzyme system was used to study toxic and antioxidant effects of F10-12 at the enzymatic level. Antioxidant characteristics of F10-12 were revealed in model solutions of organic and inorganic oxidizers. Low-concentration activation of bioluminescence was validated statistically in oxidizer solutions. Toxic and antioxidant characteristics of F10-12 were compared to those of homologous fullerenols with a higher number of oxygen groups:F24-28 and F40-42. No simple dependency was found between the toxic/antioxidant characteristics and the number of oxygen groups on the fullerene’s carbon cage. Lower toxicity and higher antioxidant activity of F24-28 were identified and presumptively attributed to its higher solubility. An active role of reactive oxygen species (ROS) in the bioeffects of F10-12 was demonstrated. Correlations between toxic/antioxidant characteristics of F10-12 and ROS content were evaluated. Toxic and antioxidant effects were related to the decrease in ROS content in the enzyme solutions. Our results reveal a complexity of ROS effects in the enzymatic assay system. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
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3.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Lonshakova-Mukina, Victoria I., Esimbekova, Elena N., Kratasyuk, Valentina A.
Заглавие : Thermal Inactivation of Butyrylcholinesterase in Starch and Gelatin Gels
Колич.характеристики :10 с
Коллективы : Government of Krasnoyarsk Territory; Krasnoyarsk Regional Fund of Science; Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR) [20-44-242001]
Место публикации : Catalysts: MDPI, 2021. - Vol. 11, Is. 4. - Ст.492. - ISSN 2073-4344(eISSN), DOI 10.3390/catal11040492
Примечания : Cited References:39. - The research was funded by the Government of Krasnoyarsk Territory, Krasnoyarsk Regional Fund of Science, and the Russian Foundation for Basic Research [project No 20-44-242001].
Аннотация: The present study demonstrates a simple approach to enhancing thermal stability of butyrylcholinesterase (BChE) by using natural polymers. Analysis of thermal inactivation of the tetrameric BChE in starch and gelatin gels at 50-64 degrees C showed that thermal inactivation followed second-order kinetics and involved two alternating processes of BChE inactivation, which occurred at different rates (fast and slow processes). The activation enthalpy Delta H-# and the activation entropy Delta S-# for BChE in starch and gelatin gels were evaluated. The values of Delta H-# for the fast and the slow thermal inactivation of BChE in starch gel were 61 +/- 3, and 22 +/- 2 kcal/mol, respectively, and the values of Delta S-# were 136 +/- 12 and -2.03 +/- 0.05 cal center dot K-1 center dot mol(-1), respectively. Likewise, the values of Delta H-# for BChE in gelatin gel were 58 +/- 6 and 109 +/- 11 kcal/mol, and the values of Delta S-# were 149 +/- 16 and 262 +/- 21 cal center dot K-1 center dot mol(-1), respectively. The values of the activation parameters obtained in this study suggest that starch gel produced a stronger stabilizing effect on BChE exposed to elevated temperatures over long periods compared with gelatin gel.
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4.

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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5.

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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6.

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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7.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Rozhko, Tatiana V., Kolesnik, Olga V., Badun, Gennadii A., Stom, Devard I., Kudryasheva, Nadezhda S.
Заглавие : Humic Substances Mitigate the Impact of Tritium on Luminous Marine Bacteria. Involvement of Reactive Oxygen Species
Колич.характеристики :12 с
Коллективы : RFBR-Krasnoyarsk Regional Foundation [N 18-44-242002, 18-44-240004]
Место публикации : Int. J. Mol. Sci.: MDPI, 2020. - Vol. 21, Is. 18. - Ст.6783. - ISSN 1422-0067(eISSN), DOI 10.3390/ijms21186783
Примечания : Cited References:74. - This work was supported by RFBR-Krasnoyarsk Regional Foundation N 18-44-242002, 18-44-240004.
Предметные рубрики: IONIZING-RADIATION
OXIDATIVE STRESS
DETOXIFICATION PROCESSES
Аннотация: The paper studies the combined effects of beta-emitting radionuclide tritium and Humic Substances (HS) on the marine unicellular microorganism-luminous bacteria-under conditions of low-dose radiation exposures (0.04 Gy). Tritium was used as a component of tritiated water. Bacterial luminescence intensity was considered as a tested physiological parameter. The bioluminescence response of the marine bacteria to tritium corresponded to the "hormesis" model: it included stages of bioluminescence inhibition and activation, as well as the absence of the effect. HS were shown to decrease the inhibition and activation effects of tritium, similar to those of americium-241, alpha-emitting radionuclide, studied earlier. Correlations between the bioluminescence intensity and the content of Reactive Oxygen Species (ROS) were found in the radioactive bacterial suspensions. The results demonstrate an important role of HS in natural processes in the regions of low radioactive contamination: HS can mitigate radiotoxic effects and adaptive response of microorganisms to low-dose radioactive exposures. The involvement of ROS in these processes was demonstrated.
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8.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Rozhko T. V., Kolesnik O. V., Badun G. A., Stom D. I., Kudryasheva N. S.
Заглавие : Humic substances mitigate the impact of tritium on luminous marine bacteria. Involvement of reactive oxygen species
Место публикации : International Journal of Molecular Sciences: MDPI AG, 2020. - Vol. 21, Is. 18. - Ст.6783. - С. 1-12. - ISSN 16616596 (ISSN), DOI 10.3390/ijms21186783
Аннотация: The paper studies the combined effects of beta-emitting radionuclide tritium and Humic Substances (HS) on the marine unicellular microorganism—luminous bacteria—under conditions of low-dose radiation exposures (0.04 Gy). Tritium was used as a component of tritiated water. Bacterial luminescence intensity was considered as a tested physiological parameter. The bioluminescence response of the marine bacteria to tritium corresponded to the “hormesis” model: it included stages of bioluminescence inhibition and activation, as well as the absence of the effect. HS were shown to decrease the inhibition and activation effects of tritium, similar to those of americium-241, alpha-emitting radionuclide, studied earlier. Correlations between the bioluminescence intensity and the content of Reactive Oxygen Species (ROS) were found in the radioactive bacterial suspensions. The results demonstrate an important role of HS in natural processes in the regions of low radioactive contamination: HS can mitigate radiotoxic effects and adaptive response of microorganisms to low-dose radioactive exposures. The involvement of ROS in these processes was demonstrated. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.
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9.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bakayan A., Picaud S., Malikova N. P., Tricoire L., Lambolez B., Vysotski E. S., Peyrieras N.
Заглавие : Redquorinxs mutants with enhanced calcium sensitivity and bioluminescence output efficiently report cellular and neuronal network activities
Место публикации : Int. J. Mol. Sci.: MDPI AG, 2020. - Vol. 21, Is. 21. - Ст.7846. - С. 1-22. - ISSN 16616596 (ISSN), DOI 10.3390/ijms21217846
Аннотация: Considerable efforts have been focused on shifting the wavelength of aequorin Ca2+? dependent blue bioluminescence through fusion with fluorescent proteins. This approach has notably yielded the widely used GFP?aequorin (GA) Ca2+ sensor emitting green light, and tdTomato-aequorin (Redquorin), whose bioluminescence is completely shifted to red, but whose Ca2+ sensitivity is low. In the present study, the screening of aequorin mutants generated at twenty?four amino acid positions in and around EF?hand Ca2+?binding domains resulted in the isolation of six aequorin single or double mutants (AequorinXS) in EF2, EF3, and C?terminal tail, which exhibited markedly higher Ca2+ sensitivity than wild?type aequorin in vitro. The corresponding Redquorin mutants all showed higher Ca2+ sensitivity than wild?type Redquorin, and four of them (RedquorinXS) matched the Ca2+ sensitivity of GA in vitro. RedquorinXS mutants exhibited unaltered thermostability and peak emission wavelengths. Upon stable expression in mammalian cell line, all RedquorinXS mutants reported the activation of the P2Y2 receptor by ATP with higher sensitivity and assay robustness than wt?Redquorin, and one, RedquorinXS?Q159T, outperformed GA. Finally, wide?field bioluminescence imaging in mouse neocortical slices showed that RedquorinXS?Q159T and GA similarly reported neuronal network activities elicited by the removal of extracellular Mg2+. Our results indicate that RedquorinXS?Q159T is a red light?emitting Ca2+ sensor suitable for the monitoring of intracellular signaling in a variety of applications in cells and tissues, and is a promising candidate for the transcranial monitoring of brain activities in living mice. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.
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10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bakayan, Adil, Picaud, Sandrine, Malikova, Natalia P., Tricoire, Ludovic, Lambolez, Bertrand, Vysotski, Eugene S., Peyrieras, Nadine
Заглавие : RedquorinXS Mutants with Enhanced Calcium Sensitivity and Bioluminescence Output Efficiently Report Cellular and Neuronal Network Activities
Колич.характеристики :20 с
Коллективы : Centre National de la Recherche ScientifiqueCentre National de la Recherche Scientifique (CNRS); Agence Nationale de la RechercheFrench National Research Agency (ANR) [ANR-10-INBS-04, ANR-11-EQPX-029]; Fondation pour la Recherche sur le Cerveau/Rotary Club de France; RFBRRussian Foundation for Basic Research (RFBR) [20-04-00085]
Место публикации : Int. J. Mol. Sci.: MDPI, 2020. - Vol. 21, Is. 21. - Ст.7846. - ISSN 1422-0067(eISSN), DOI 10.3390/ijms21217846
Примечания : Cited References:53. - This work was supported by grants from Centre National de la Recherche Scientifique (AAP Prematuration CNRS 2016, to A.B. and N.P.; equipment transfer to S.P. and B.L.), from Agence Nationale de la Recherche (AAP Prematuration FCS/IDEX Paris Saclay, to A.B. and N.P., France BioImaging infrastructure ANR-10-INBS-04, ANR-11-EQPX-029 to N.P.), from Fondation pour la Recherche sur le Cerveau/Rotary Club de France (B.L.), and from RFBR (project number 20-04-00085 to N.P.M. and E.S.V.). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Предметные рубрики: IN-VIVO
PHOTOPROTEIN AEQUORIN
CA2+-REGULATED PHOTOPROTEINS
SPREADING
Аннотация: Considerable efforts have been focused on shifting the wavelength of aequorin Ca2+-dependent blue bioluminescence through fusion with fluorescent proteins. This approach has notably yielded the widely used GFP-aequorin (GA) Ca2+ sensor emitting green light, and tdTomato-aequorin (Redquorin), whose bioluminescence is completely shifted to red, but whose Ca2+ sensitivity is low. In the present study, the screening of aequorin mutants generated at twenty-four amino acid positions in and around EF-hand Ca2+-binding domains resulted in the isolation of six aequorin single or double mutants (AequorinXS) in EF2, EF3, and C-terminal tail, which exhibited markedly higher Ca2+ sensitivity than wild-type aequorin in vitro. The corresponding Redquorin mutants all showed higher Ca2+ sensitivity than wild-type Redquorin, and four of them (RedquorinXS) matched the Ca2+ sensitivity of GA in vitro. RedquorinXS mutants exhibited unaltered thermostability and peak emission wavelengths. Upon stable expression in mammalian cell line, all RedquorinXS mutants reported the activation of the P2Y2 receptor by ATP with higher sensitivity and assay robustness than wt-Redquorin, and one, RedquorinXS-Q159T, outperformed GA. Finally, wide-field bioluminescence imaging in mouse neocortical slices showed that RedquorinXS-Q159T and GA similarly reported neuronal network activities elicited by the removal of extracellular Mg2+. Our results indicate that RedquorinXS-Q159T is a red light-emitting Ca2+ sensor suitable for the monitoring of intracellular signaling in a variety of applications in cells and tissues, and is a promising candidate for the transcranial monitoring of brain activities in living mice.
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11.

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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12.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bolsunovsky A., Melgunov M.
Заглавие : Radioactive particles in the Yenisei River floodplain (Russia): Characterization, leaching and potential effects in the environment
Место публикации : J. Environ. Radioact.: Elsevier Ltd, 2019. - Vol. 208-209. - ISSN 0265931X (ISSN) , DOI 10.1016/j.jenvrad.2019.105991
Аннотация: The operation of the Mining-and-Chemical Combine (MCC), the largest producer of weapons-grade plutonium in Russia, has resulted in radioactive contamination of the Yenisei River floodplain. Investigations carried out in Novosibirsk and Krasnoyarsk institutes have shown that the floodplain of the Yenisei downstream of the MCC is contaminated by radioactive particles (RP) of various types and activities. Analytical characterization of the RP showed that most of them were fuel particles, which were carried into the Yenisei after incidents at the MCC reactors. The plutonium and caesium isotope ratios (238Pu/239,240Pu; 137Cs/134Cs) vary substantially between the particles, indicating different source terms and time intervals when the RP were formed. In addition to fuel RP, there were particles that contained activation radionuclides. The experiment on dissolution of RP using the model solution (the simulated stomach fluid) showed different cumulative extractions of radionuclides from the particles: 60Co and 137Cs extractions were the lowest, the extracted fractions of europium and americium isotopes were the largest, and plutonium occupied an intermediate position. High concentrations of radionuclides in RP are sources of exposure of organisms in aquatic and terrestrial ecosystems to low radiation doses. The plant bioassays of the effects of ?-radiation from RP showed the effect of low doses of ?-radiation on growth parameters of aquatic plant Elodea canadensis growing in the Yenisei River floodplain. The presence of RP from different sources in the Yenisei River floodplain makes this region a unique site for studying environmental effects of the particles. © 2019 Elsevier Ltd
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13.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Nesterenko T. V., Shikhov V. N., Tikhomirov A. A.
Заглавие : The fluorescence method for determining of photosynthetic apparatus reactivity in plant leaves
Колич.характеристики :13 с
Место публикации : Zhurnal Obshchei Biol.: MEZHDUNARODNAYA KNIGA, 2019. - Vol. 80, Is. 3. - С. 187-199. - ISSN 0044-4596, DOI 10.1134/S0044459619030060
Примечания : Cited References:31
Предметные рубрики: ELECTRIC-POTENTIAL DIFFERENCE
FREQUENTLY ASKED QUESTIONS
CHLOROPHYLL
Аннотация: Presently, the most promising way of studying, forecasting, and enhancing of organisms' tolerance to harsh environmental impacts is considered to be the estimation of initial functional state of an organism's regulatory systems. To resolve the problem of photosynthetic apparatus (PSA) tolerance to harsh impacts at the level of such a complicated functional system as a plant leaf, it is necessary to assess integral responses of the leaf's PSA to the impact. At that, simple and versatile traits may have certain advantages. At present, chlorophyll fluorescence seems to be one of the main indices of PSA activity, which can be measured relatively fast and easy. One of the possible approaches to operational integrative assessment of PSA activity may consist in usage of the parameters introduced for the curves of chlorophyll fluorescence induction (CFI) slow phase. Temporal patterns of CFI are of special interest. The simplest index T-0.5 (i.e., half-time of chlorophyll fluorescence intensity decrease during the slow phase of CFI) appears to be an integral characteristic of activation rate with regard to a number of photo-assimilation and photo-protective processes in leaves. On basis of the studies, conducted earlier, and published data, we have analyzed the behavior of T-0.5 parameter with comparison to other CFI traits (namely: qN - non-photochemical quenching coefficient, ETR - electron transport rate, Phi(PSII) - effective quantum yield of PSII photochemistry, F-p/F-T ratio) under different conditions. The influence of leaf senescence, changes in intensity of excitation light, slight dehydration of plants and their recovery from water deficiency have been examined. The pattern of T-0.5 behavior, observed in laboratory experiments, and the results of its comparison with other indices of CFI give occasion to propose the usage of T-0.5 for indirect estimation of PSA activity when operational integrative monitoring of PSA state is required. Further studies are necessary for establishing quantitative relationships between PSA activity and fluorescence parameter T-0.5 under specific stress conditions.
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14.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Govorun A. E., Esimbekova E. N., Kratasyuk V. A.
Заглавие : NAD(P)H:FMN-Oxidoreductase Functioning Under Macromolecular Crowding: In Vitro Modeling
Место публикации : Doklad. Biochem. Biophys.: Pleiades Publishing, 2019. - Vol. 486, Is. 1. - С. 213-215. - ISSN 16076729 (ISSN) , DOI 10.1134/S160767291903013X
Аннотация: The functioning of NAD(P)H:FMN‑oxidoreductase (Red) from Vibrio fischeri under conditions of macromolecular crowding (MMC) simulated in vitro by adding biopolymers (starch and gelatin) was studied. The dissociation rate constants and the activation energies of dissociation of Red to the subunits were calculated, and the process of denaturation of Red was analyzed. It is shown that the functioning of Red both under conditions of MMC and in diluted solutions is the same. This result refutes the common belief that the native conformation of enzymes in vivo is stabilized due to MMC as compared to the in vitro conditions. © 2019, Pleiades Publishing, Ltd.
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15.

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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16.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Pande, Shubhra, Kratasyuk, Valentina A., Medvedeva, Nadezhda N., Kolenchukova, Oxana A., Salmina, Alla B.
Заглавие : Nutritional biomarkers: Current view and future perspectives
Колич.характеристики :15 с
Коллективы : Russian Foundation for Basic Research [16-06-00-439]; Russian Ministry of Education [M 2.2.3]; Russian Foundation for Basic Research; Krasnoyarsk Regional Fund for Scientific and Technical Activity Support [16-44-242126]
Место публикации : Crit. Rev. Food Sci. Nutr.: TAYLOR & FRANCIS INC, 2018. - Vol. 58, Is. 18. - С. 3055-3069. - ISSN 1040-8398, DOI 10.1080/10408398.2017.1350136. - ISSN 1549-7852(eISSN)
Примечания : Cited References:163. - The research was partially supported by the Russian Foundation for Basic Research [Grant No 16-06-00-439], the Russian Ministry of Education, Post-Doctoral Program of Project "5-100" [Grant No. M 2.2.3] and the Russian Foundation for Basic Research in collaboration with Krasnoyarsk Regional Fund for Scientific and Technical Activity Support [project No 16-44-242126].
Предметные рубрики: PROMOTES CELL-SURVIVAL
FATTY-ACID OXIDATION
CALORIE RESTRICTION
Ключевые слова (''Своб.индексиров.''): sirtuins--nad--biomarker--proteomics--calorie restriction--longitivity
Аннотация: There is a poor relationship between nutrient intake and existing nutritional biomarkers due to variety of factors affecting their sensitivity and specificity. To explore the impact of nutrients at molecular level and devising a sensitive biomarker, proteomics is a central technology with sirtuins as one of the most promising nutritional biomarker. Sirtuins (seven mammalian sirtuins reported so far) have been reported to perform protein deacetylases and ADP-ribosyltransferases activity. It is distributed in different cellular compartments thereby controlling several metabolic processes. Sirtuins are oxidized nicotinamide adenine dinucleotide dependent, which implicates a direct effect of the metabolic state of the cell on its activity. Calorie restriction upregulates the mammalian sirtuin protein levels in variety of tissues and organs where it acts upon both histone and nonhistone substrates. Sirtuin senses nutrient availability and impacts gluconeogenesis, glycolysis, and insulin sensitivity. It deacetylates and inhibits the nuclear receptor that activates fat synthesis and adipogenesis in the body, leading to fat loss and bringing favorable cellular and health changes. Sirtuins mediates intracellular response that promotes cell survival, DNA damage repair thereby increasing the cell longitivity. The activation of sirtuins brings a wide spectrum of other health benefits and its activity levels are indicative of nutritional status as well as disease progression in cancer, inflammation, obesity, cardiovascular diseases, and viral infections. There are several foods that activate sirtuin activity and offer significant health benefits by their consumption.
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17.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Rozhko T. V., Guseynov O. A., Guseynova V. E., Bondar A. A., Devyatlovskaya A. N., Kudryasheva N. S.
Заглавие : Is bacterial luminescence response to low-dose radiation associated with mutagenicity?
Место публикации : J. Environ. Radioact.: Elsevier Ltd, 2017. - Vol. 177. - С. 261-265. - ISSN 0265931X (ISSN) , DOI 10.1016/j.jenvrad.2017.07.010
Ключевые слова (''Своб.индексиров.''): bioassay--dna--low-dose radiation--luminous marine bacteria--mutations--bacteria--bioassay--bioluminescence--chemical activation--dna--dna sequences--genes--ionizing radiation--kinetics--luminescence--nucleic acids--phosphorescence--physiological models--radioisotopes--bacterial suspensions--beta-emitting radionuclides--low dose radiation--luminescence intensity--marine bacterium--mutations--photobacterium phosphoreum--physiological parameters--radiation--bacteria (microorganisms)--photobacterium phosphoreum
Аннотация: Luminous marine bacteria are widely used in bioassays with luminescence intensity being a physiological parameter tested. The purpose of the study was to determine whether bacterial genetic alteration is responsible for bioluminescence kinetics change under low-dose radiation exposure. The alpha-emitting radionuclide 241Am and beta-emitting radionuclide 3H were used as the sources of low-dose ionizing radiation. Changes of bioluminescence kinetics of Photobacterium phosphoreum in solutions of 241Am(NO3)3, 7 kBq/L, and tritiated water, 100 MBq/L, were studied; bioluminescence kinetics stages (absence of effect, activation, and inhibition) were determined. Bacterial suspension was sampled at different stages of the bioluminescent kinetics; the doses accumulated by the samples were close or a little higher than a tentative limit of a low-dose interval: 0.10 and 0.85 Gy for 241Am, or 0.11 and 0.18 Gy for 3H. Sequence analysis of the 16S ribosomal RNA gene did not reveal a mutagenic effect of low-dose alpha and beta radiation in the bacterial samples. Previous results on bacterial DNA exposed to low-dose gamma radiation (0.25 Gy) were analyzed and compared to those for alpha and beta irradiation. It is concluded that bioluminescence activation and/or inhibition under the applied conditions of low-dose alpha, beta and gamma radioactive exposure is not associated with DNA mutations in the gene sequences tested. © 2017 Elsevier Ltd
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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) : 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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20.

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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