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1.


   
    The interaction of C-terminal Tyr208 and Tyr13 of the first alpha-helix ensures a closed conformation of ctenophore photoprotein berovin / L. P. Burakova, E. V. Eremeeva, E. S. Vysotski // Photochem. Photobiol. Sci. - 2020. - Vol. 19, Is. 3. - P313-323, DOI 10.1039/c9pp00436j. - Cited References:49. - This work was supported by grant 17-04-00764 of the Russian Foundation for Basic Research. . - ISSN 1474-905X. - ISSN 1474-9092
РУБ Biochemistry & Molecular Biology + Biophysics + Chemistry, Physical
Рубрики:
LIGHT-SENSITIVE PHOTOPROTEIN
   GREEN FLUORESCENT PROTEIN

Аннотация: Light-sensitive Ca2+-regulated photoprotein berovin is responsible for the bioluminescence of the ctenophore Beroe abyssicola. It shares many properties of hydromedusan photoproteins although the degree of identity of its amino acid sequence with those of photoproteins is low. There is a hydrogen bond between C-terminal Pro and Arg situated in the N-terminal alpha-helix of hydromedusan photoproteins that supports a closed conformation of the internal cavity of the photoprotein molecule with bound 2-hydroperoxycoelenterazine. The C- and N-terminal hydrogen bond network is necessary to properly isolate the photoprotein active site from the solvent and consequently to provide a high quantum yield of the bioluminescence reaction. In order to find out which berovin residues perform the same function we modified the N- and C-termini of the protein by replacing or deleting various amino acid residues. The studies on berovin mutants showed that the interaction between C-terminal Tyr208 and Tyr13 localized in the first alpha-helix of the photoprotein is important for the stabilization and proper orientation of the oxygenated coelenterazine adduct within the internal cavity as well as for supporting the closed photoprotein conformation. We also suggest that the interplay between Tyr residues in ctenophore photoproteins occurs rather through the pi-pi interaction of their phenyl rings than through hydrogen bonds as in hydromedusan photoproteins.

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Держатели документа:
RAS, SB, Photobiol Lab, Inst Biophys,Fed Res Ctr,Krasnoyarsk Sci Ctr, Krasnoyarsk, Russia.

Доп.точки доступа:
Burakova, Ludmila P.; Eremeeva, Elena V.; Vysotski, Eugene S.; Vysotski, Eugene; Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR) [17-04-00764]

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2.


   
    Usage of different neural networks in identification of plant types / S. Bartsev, Y. Ivanova, M. Saltykov // IOP Conference Series: Materials Science and Engineering : Institute of Physics Publishing, 2020. - Vol. 734: 2nd International Scientific Conference on Advanced Technologies in Aerospace, Mechanical and Automation Engineering, MIST: Aerospace 2019 (18 November 2019 through 21 November 2019, ) Conference code: 157461, Is. 1. - Ст. 012097, DOI 10.1088/1757-899X/734/1/012097
Аннотация: Since introduction of neural networks into remote sensing they demonstrate good efficiency in remote sensing data analysis. This work is devoted to processing of multispectral (12 bands) images from Sentinel-2(A, B) satellites. Satellite images of areas in Krasnoyarsk Region and Khakassia with known vegetation types are used as task books to train neural networks. Trained neural networks have been reduced to determine which bands are significant for vegetation type identification. Reduction of trained neural network show that vegetation type can be determined from only four infrared bands without significant loses in performance in comparison with non-reduced neural network. © Published under licence by IOP Publishing Ltd.

Scopus
Держатели документа:
Institute of Biophysics FRC KSC SB RAS, Akademgorodok 50/50, Krasnoyarsk, 660036, Russian Federation

Доп.точки доступа:
Bartsev, S.; Ivanova, Y.; Saltykov, M.

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3.


   
    Bioluminescent properties of semi-synthetic obelin and aequorin activated by coelenterazine analogues with modifications of C-2, C-6, and C-8 substituents / E. V. Eremeeva, T. Jiang, N. P. Malikova [et al.] // Int. J. Mol. Sci. - 2020. - Vol. 21, Is. 15. - Ст. 5446. - P1-21, DOI 10.3390/ijms21155446 . - ISSN 1661-6596
Кл.слова (ненормированные):
Aequorin -- Analogues -- Coelenterazine -- Obelin -- Photoprotein
Аннотация: Ca2+-regulated photoproteins responsible for bioluminescence of a variety of marine organisms are single-chain globular proteins within the inner cavity of which the oxygenated coelenterazine, 2-hydroperoxycoelenterazine, is tightly bound. Alongside with native coelenterazine, photoproteins can also use its synthetic analogues as substrates to produce flash-type bioluminescence. However, information on the effect of modifications of various groups of coelenterazine and amino acid environment of the protein active site on the bioluminescent properties of the corresponding semi-synthetic photoproteins is fragmentary and often controversial. In this paper, we investigated the specific bioluminescence activity, light emission spectra, stopped-flow kinetics and sensitivity to calcium of the semi-synthetic aequorins and obelins activated by novel coelenterazine analogues and the recently reported coelenterazine derivatives. Several semi-synthetic photoproteins activated by the studied coelenterazine analogues displayed sufficient bioluminescence activities accompanied by various changes in the spectral and kinetic properties as well as in calcium sensitivity. The poor activity of certain semi-synthetic photoproteins might be attributed to instability of some coelenterazine analogues in solution and low efficiency of 2-hydroperoxy adduct formation. In most cases, semi-synthetic obelins and aequorins displayed different properties upon being activated by the same coelenterazine analogue. The results indicated that the OH-group at the C-6 phenyl ring of coelenterazine is important for the photoprotein bioluminescence and that the hydrogen-bond network around the substituent in position 6 of the imidazopyrazinone core could be the reason of different bioluminescence activities of aequorin and obelin with certain coelenterazine analogues. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.

Scopus
Держатели документа:
Photobiology Laboratory, Institute of Biophysics SB RAS, Federal Research Center “Krasnoyarsk Science Center SB RAS”, Krasnoyarsk, 660036, Russian Federation
Key Laboratory of Chemical Biology (MOE), Department of Medicinal Chemistry, School of Pharmaceutical Sciences, Shandong University, Jinan, Shandong 250012, China
State Key Laboratory of Microbial Technology, Shandong University–Helmholtz Institute of Biotechnology, Shandong University, Qingdao, Shandong 266237, China

Доп.точки доступа:
Eremeeva, E. V.; Jiang, T.; Malikova, N. P.; Li, M.; Vysotski, E. S.

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4.


   
    The interaction of C-terminal Tyr208 and Tyr13 of the first α-helix ensures a closed conformation of ctenophore photoprotein berovin / L. P. Burakova, E. V. Eremeeva, E. S. Vysotski // Photochem. Photobiol. Sci. - 2020. - Vol. 19, Is. 3. - P313-323, DOI 10.1039/c9pp00436j . - ISSN 1474-905X
Кл.слова (ненормированные):
Amino acids -- Bioluminescence -- Conformations -- Phosphorescence -- Amino acid residues -- Amino acid sequence -- Hydrogen bond networks -- Hydromedusan -- Internal cavities -- Phenyl rings -- Photoproteins -- Pi interactions -- Hydrogen bonds
Аннотация: Light-sensitive Ca2+-regulated photoprotein berovin is responsible for the bioluminescence of the ctenophore Beroe abyssicola. It shares many properties of hydromedusan photoproteins although the degree of identity of its amino acid sequence with those of photoproteins is low. There is a hydrogen bond between C-terminal Pro and Arg situated in the N-terminal ?-helix of hydromedusan photoproteins that supports a closed conformation of the internal cavity of the photoprotein molecule with bound 2-hydroperoxycoelenterazine. The C- and N-terminal hydrogen bond network is necessary to properly isolate the photoprotein active site from the solvent and consequently to provide a high quantum yield of the bioluminescence reaction. In order to find out which berovin residues perform the same function we modified the N- and C-termini of the protein by replacing or deleting various amino acid residues. The studies on berovin mutants showed that the interaction between C-terminal Tyr208 and Tyr13 localized in the first ?-helix of the photoprotein is important for the stabilization and proper orientation of the oxygenated coelenterazine adduct within the internal cavity as well as for supporting the closed photoprotein conformation. We also suggest that the interplay between Tyr residues in ctenophore photoproteins occurs rather through the ?-? interaction of their phenyl rings than through hydrogen bonds as in hydromedusan photoproteins. This journal is © The Royal Society of Chemistry and Owner Societies.

Scopus
Держатели документа:
Photobiology Laboratory, Institute of Biophysics SB RAS, Federal Research Center Krasnoyarsk Science Center SB RAS, Krasnoyarsk, Russian Federation

Доп.точки доступа:
Burakova, L. P.; Eremeeva, E. V.; Vysotski, E. S.

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5.


   
    Production of a Composite Based on Alumina Nanofibers and Detonation Nanodiamonds for Creating Phenol Indication Systems / N. O. Ronzhin, E. D. Posokhina, E. V. Mikhlina [et al.] // Dokl. Chem. - 2019. - Vol. 489, Is. 1. - P267-271, DOI 10.1134/S001250081911003X . - ISSN 0012-5008
Аннотация: Abstract: A composite of alumina nanofibers (ANF) and modified detonation nanodiamonds (MDND) was produced by mixing aqueous suspensions of the components in a weight ratio of 5 : 1 with subsequent incubation of the mixture for 15 min at 32°C. It was assumed that the formation of the composite is ensured by the difference of the zeta potentials of the components, which is negative for MDND and positive for ANF. Vacuum filtration of the mixture through a fluoroplastic filter (pore diameter 0.6 ?m) formed disks 40 mm in diameter, which were then heat-treated at 300°C to impart structural stability to the composite. Scanning electron microscopy detected that the obtained composite has a network structure, in which MDND particles are distributed over the surface of ANF. It was determined that the MDND particles incorporated in the composite catalyze the phenol–4-aminoantipyrine–H2O2 oxidative azo coupling reaction to form a colored product (quinoneimine). The applicability of the composite to repeated phenol detection in aqueous samples was demonstrated. © 2019, Pleiades Publishing, Ltd.

Scopus
Держатели документа:
Institute of Biophysics, Krasnoyarsk Scientific Center, Siberian Branch, Russian Academy of Sciences, AkademgorodokKrasnoyarsk, 660036, Russian Federation
Siberian Federal University, Krasnoyarsk, 660041, Russian Federation
Institute of Computational Modeling, Krasnoyarsk Scientific Center, Siberian Branch, Russian Academy of Sciences, AkademgorodokKrasnoyarsk, 660036, Russian Federation
Krasnoyarsk Scientific Center, Siberian Branch, Russian Academy of Sciences, AkademgorodokKrasnoyarsk, 660036, Russian Federation

Доп.точки доступа:
Ronzhin, N. O.; Posokhina, E. D.; Mikhlina, E. V.; Simunin, M. M.; Nemtsev, I. V.; Ryzhkov, I. I.; Bondar, V. S.

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6.


   
    Neural networks playing 'matching pennies' with each other: Reproducibility of game dynamics / T. Dolgova, S. Bartsev // IOP Conference Series: Materials Science and Engineering : Institute of Physics Publishing, 2019. - Vol. 537: International Workshop on Advanced Technologies in Material Science, Mechanical and Automation Engineering - MIP: Engineering-2019 (4 April 2019 through 6 April 2019, ) Conference code: 149243, Is. 4, DOI 10.1088/1757-899X/537/4/042002
Кл.слова (ненормированные):
Condensed matter physics -- Engineering -- Industrial engineering -- Materials science -- Cognitive functions -- Dynamic patterns -- Essential features -- Meta strategies -- Neural correlates of consciousness -- Neuron excitation -- Qualitative differences -- Reproducibilities -- Recurrent neural networks
Аннотация: Reflection is an essential feature of consciousness and possibly the single most important one. This fact allows us to simplify the objective of the concept of 'neural correlates of consciousness' and to focus investigations on reflection itself. Reflexive games are the concentrated and pure embodiment of reflection manifestation without the addition of other higher cognitive functions. In this paper, we use the game 'matching pennies' ("Odd-Even") in order to trace the strategies and possible patterns of recurrent neural network operation. Experimental results show the splitting of all considered game patterns into two groups. A significant difference was observed in these groups of patterns, indicating a qualitative difference in game dynamics apparently due to the qualitatively different dynamic patterns of neuron excitations of the networks. A similar splitting of all players into two groups was found by other authors for human players, which differ in terms of the reflection availability. By this, we can assume that one of the causes of the splitting is that the presence of reflection in a particular group of recurrent neural networks dramatically changes the game meta-strategy. © Published under licence by IOP Publishing Ltd.

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Держатели документа:
Siberian Federal University, 2 79 Svobodny pr., Krasnoyarsk, 660041, Russian Federation
Institute of Biophysics SB RAS, Federal Research Center, Krasnoyarsk Scientific Center SB RAS, 50, Akademgorodok, Krasnoyarsk, 660036, Russian Federation

Доп.точки доступа:
Dolgova, T.; Bartsev, S.

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7.


   
    Recurrent and multi-layer neural networks playing Even-Odd": Reflection against regression / S. Bartsev, G. Markova // IOP Conference Series: Materials Science and Engineering : Institute of Physics Publishing, 2020. - Vol. 734: 2nd International Scientific Conference on Advanced Technologies in Aerospace, Mechanical and Automation Engineering, MIST: Aerospace 2019 (18 November 2019 through 21 November 2019, ) Conference code: 157461, Is. 1. - Ст. 012109, DOI 10.1088/1757-899X/734/1/012109
Аннотация: Reflection understood as an internal representation of the external world by the subject is the key property of consciousness. In a refined form this property is manifested in reflective games. To win a reflective game a player has to use reflection of strictly one rank higher than the opponent. So it can be assumed that there are only two game modes - when only one player uses reflection and wins and when both players use reflection but one of them chooses incorrect reflection rank. The option of random move selection is not considered since firstly, starting the game for a draw is strange, and secondly, it is technically impossible to make random moves without a special device. Experiments with recurrent neural networks playing with each other showed that the entire set of game patterns (time series of the game score) is split into two sharply different groups that can be associated with two modes mentioned above. Experiments, in which a multilayer neural network, which is basically incapable of reflection, played against a recurrent neural network, showed that a recurrent neural network has a clear advantage winning confidently in more than 90% of the games. At the same time game patterns demonstrate splitting into two sharply different groups as was observed in experiments with the game of two recurrent neural networks and in the reflexive game of living people. © Published under licence by IOP Publishing Ltd.

Scopus
Держатели документа:
Institute of Biophysics SB RAS, Federal Research Center, Krasnoyarsk Scientific Center SB RAS, 50, Akademgorodok, Krasnoyarsk, 660036, Russian Federation
Siberian Federal University, 79 Svobodny pr., Krasnoyarsk, 660041, Russian Federation

Доп.точки доступа:
Bartsev, S.; Markova, G.

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8.


   
    Production of a Composite Based on Alumina Nanofibers and Detonation Nanodiamonds for Creating Phenol Indication Systems / N. O. Ronzhin, E. D. Posokhina, E. V. Mikhlina [et al.] // Dokl. Chem. - 2019. - Vol. 489. - P267-271, DOI 10.1134/S001250081911003X. - Cited References:13. - This work was supported by the Russian Foundation for Basic Research (project no. 18-29-19078 mk). . - ISSN 0012-5008. - ISSN 1608-3113
РУБ Chemistry, Multidisciplinary
Рубрики:
NANOPARTICLES
   GRAPHENE

Аннотация: A composite of alumina nanofibers (ANF) and modified detonation nanodiamonds (MDND) was produced by mixing aqueous suspensions of the components in a weight ratio of 5 : 1 with subsequent incubation of the mixture for 15 min at 32 degrees C. It was assumed that the formation of the composite is ensured by the difference of the zeta potentials of the components, which is negative for MDND and positive for ANF. Vacuum filtration of the mixture through a fluoroplastic filter (pore diameter 0.6 mu m) formed disks 40 mm in diameter, which were then heat-treated at 300 degrees C to impart structural stability to the composite. Scanning electron microscopy detected that the obtained composite has a network structure, in which MDND particles are distributed over the surface of ANF. It was determined that the MDND particles incorporated in the composite catalyze the phenol-4-aminoantipyrine-H2O2 oxidative azo coupling reaction to form a colored product (quinoneimine). The applicability of the composite to repeated phenol detection in aqueous samples was demonstrated.

WOS
Держатели документа:
Russian Acad Sci, Siberian Branch, Krasnoyarsk Sci Ctr, Inst Biophys, Krasnoyarsk 660036, Russia.
Siberian Fed Univ, Krasnoyarsk 660041, Russia.
Russian Acad Sci, Siberian Branch, Inst Computat Modeling, Krasnoyarsk Sci Ctr, Krasnoyarsk 660036, Russia.
Russian Acad Sci, Siberian Branch, Krasnoyarsk Sci Ctr, Krasnoyarsk 660036, Russia.

Доп.точки доступа:
Ronzhin, N. O.; Posokhina, E. D.; Mikhlina, E. V.; Simunin, M. M.; Nemtsev, I. V.; Ryzhkov, I. I.; Bondar, V. S.; Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR) [18-29-19078 mk]

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9.


   
    A new composite material based on alumina nanofibers and detonation nanodiamonds: synthesis, characterization, and sensing application / N. O. Ronzhin, E. D. Posokhina, E. V. Mikhlina [et al.] // J. Nanopart. Res. - 2021. - Vol. 23, Is. 9. - Ст. 199, DOI 10.1007/s11051-021-05309-y. - Cited References:57. - This work is partially supported by the Russian Foundation for Basic Research, Project 18-29-19078 (E. V. Mikhlina, M. M. Simunin, I. Ryzhkov). . - ISSN 1388-0764. - ISSN 1572-896X
РУБ Chemistry, Multidisciplinary + Nanoscience & Nanotechnology + Materials
Рубрики:
ELECTROCHEMICAL ENERGY-STORAGE
   SELECTIVE DETECTION

   PHENOL DETECTION

Кл.слова (ненормированные):
Nanodiamonds -- Alumina nanofibers -- Composite -- Indicator system -- Phenol
Аннотация: The development of inexpensive, easy-to-produce, and easy-to-use analytical tools for detection of harmful and toxic substances is a relevant research problem with direct applications in environmental monitoring and protection. In this work, we propose a novel composite material based on alumina nanofibers and detonation nanodiamonds for detection of phenol in aqueous medium. The composite material was obtained by mixing an aqueous suspension of alumina nanofibers with a diameter of 10-15 nm and a length of several microns and a hydrosol of nanodiamonds with an average cluster size of 70 nm. The mechanisms underlying the interaction of these nanomaterials are clarified and the physicochemical properties of the composite are investigated. The SEM and TEM studies show that the obtained composite has a network structure, in which clusters of nanodiamonds (10-20 nm in diameter) are distributed over the surface of nanofibers. Coupling of nanomaterials occurs due to opposite signs of their zeta potentials, which results in electrostatic attraction and subsequent chemical bonding as indicated by the X-ray photoelectron spectroscopy and simultaneous thermal analysis. The bonding apparently occurs between functional groups (mainly carboxyl) on the surface of nanodiamonds and amphoteric hydroxyl groups on the surface of alumina nanofibers. The proposed composite allows an easy-to-perform colorimetric analysis for qualitative and quantitative determination of phenol in aqueous samples with linear response over a wide range of concentrations (0.5-106 mu M). Multiple tests have shown that the composite is reusable and retains its catalytic function for at least 1 year during storage at room temperature.

WOS
Держатели документа:
Inst Biophys SB RAS, Akademgorodok 50-50, Krasnoyarsk 660036, Russia.
Siberian Fed Univ, Svobodny 79, Krasnoyarsk 660041, Russia.
Inst Computat Modelling SB RAS, Akademgorodok 50-44, Krasnoyarsk 660036, Russia.
Inst Chem & Chem Technol SB RAS, Akademgorodok 50-24, Krasnoyarsk 660036, Russia.
Fed Res Ctr KSC SB RAS, Akademgorodok 50-38, Krasnoyarsk 660036, Russia.

Доп.точки доступа:
Ronzhin, Nikita O.; Posokhina, Ekaterina D.; Mikhlina, Elena, V; Mikhlin, Yuri L.; Simunin, Mikhail M.; Tarasova, Lyudmila S.; Vorobyev, Sergey A.; Bondar, Vladimir S.; Ryzhkov, Ilya I.; Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR) [18-29-19078]

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10.


   
    RedquorinXS Mutants with Enhanced Calcium Sensitivity and Bioluminescence Output Efficiently Report Cellular and Neuronal Network Activities / A. Bakayan, S. Picaud, N. P. Malikova [et al.] // Int. J. Mol. Sci. - 2020. - Vol. 21, Is. 21. - Ст. 7846, DOI 10.3390/ijms21217846. - 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. . - ISSN 1422-0067
РУБ Biochemistry & Molecular Biology + Chemistry, Multidisciplinary
Рубрики:
IN-VIVO
   PHOTOPROTEIN AEQUORIN

   CA2+-REGULATED PHOTOPROTEINS

   SPREADING

Кл.слова (ненормированные):
bioluminescence -- aequorin -- calcium sensor -- BRET -- mutagenesis -- GPCR -- assay -- neuronal network imaging
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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Держатели документа:
Ctr Natl Rech Sci CNRS, Inst Neurobiol Alfred Fessard, UPR 3294, Ave Terrasse, F-91198 Gif Sur Yvette, France.
Univ Paris Saclay, BioEmergences Unit, CNRS, USR 3695, Ave Terrasse, F-91198 Gif Sur Yvette, France.
Sorbonne Univ, Inst Biol Paris Seine NPS IBPS, INSERM, Neurosci Paris Seine,CNRS,UMR8246,U1130,UM119, F-75005 Paris, France.
Inst Biophys SB RAS, Fed Res Ctr, Photobiol Lab, Krasnoyarsk Sci Ctr SB RAS, Krasnoyarsk 660036, Russia.

Доп.точки доступа:
Bakayan, Adil; Picaud, Sandrine; Malikova, Natalia P.; Tricoire, Ludovic; Lambolez, Bertrand; Vysotski, Eugene S.; Peyrieras, Nadine; Vysotski, Eugene; 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]

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11.


   
    H2O-Bridged Proton-Transfer Channel in Emitter Species Formation in Obelin Bioluminescence / S. F. Chen, E. S. Vysotski, Y. J. Liu // J. Phys. Chem. B. - 2021. - Vol. 125, Is. 37. - P10452-10458, DOI 10.1021/acs.jpcb.1c03985. - 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). . - ISSN 1520-6106. - ISSN 1520-5207
РУБ Chemistry, Physical
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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Держатели документа:
Shanghai Inst Technol, Sch Chem & Environm Engn, Shanghai 201418, Peoples R China.
Fed Res Ctr Krasnoyarsk Sci Ctr SB RAS, Inst Biophys SB RAS, Photo Biol Lab, Krasnoyarsk 660036, Russia.
Beijing Normal Univ Zhuhai, Ctr Adv Mat Res, Adv Inst Nat Sci, Zhuhai 519087, Peoples R China.
Beijing Normal Univ, Coll Chem, Key Lab Theoret & Computat Photochem, Minist Educ, Beijing 100875, Peoples R China.

Доп.точки доступа:
Chen, Shu-Feng; Vysotski, Eugene S.; Liu, Ya-Jun; Vysotski, Eugene; 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]

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12.


   
    H2O-Bridged Proton-Transfer Channel in Emitter Species Formation in Obelin Bioluminescence / S. -F. Chen, E. S. Vysotski, Y. -J. Liu // J Phys Chem B. - 2021, DOI 10.1021/acs.jpcb.1c03985 . - Article in press. - ISSN 1520-6106
Кл.слова (ненормированные):
Amino acids -- Excited states -- Hydrogen bonds -- Molecular dynamics -- Molecular modeling -- Molecules -- Phosphorescence -- Proton transfer -- Quantum theory -- Fast protons -- Marine organisms -- Photoproteins -- Primary products -- Proton transfer process -- Quantum mechanics/molecular mechanics -- Reaction substrates -- Singlet excited state -- Theoretical calculations -- Transfer channel -- Bioluminescence
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.

Scopus
Держатели документа:
School of Chemical and Environmental Engineering, Shanghai Institute of Technology, Shanghai, 201418, China
Photobiology Laboratory, Institute of Biophysics SB RAS, Federal Research Center, Krasnoyarsk Science Center SB RAS, Krasnoyarsk, 660036, Russian Federation
Center for Advanced Materials Research, Advanced Institute of Natural Sciences, Beijing Normal University at Zhuhai, Zhuhai, 519087, China
Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, 100875, China

Доп.точки доступа:
Chen, S. -F.; Vysotski, E. S.; Liu, Y. -J.

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13.


   
    A heuristic neural network model in the research of properties of evolutionary trajectories / S. Bartsev, P. Baturina // INTERNATIONAL WORKSHOP ADVANCED TECHNOLOGIES IN MATERIAL SCIENCE, : IOP PUBLISHING LTD, 2019. - Vol. 537: International Workshop on Advanced Technologies in Material Science, (APR 04-06, 2019, Krasnoyarsk, RUSSIA). - Ст. 042001. - (IOP Conference Series-Materials Science and Engineering), DOI 10.1088/1757-899X/537/4/042001. - Cited References:21 . -
РУБ Engineering, Mechanical + Materials Science, Multidisciplinary
Рубрики:
SEQUENCE SPACE
Аннотация: There is considerable data on molecular evolution, but there remains no approach to systematizing them within the framework of the key problems of biology. To search for the most common properties of evolving systems, the heuristic method has been proposed. Artificial networks of formal neurons were chosen as the heuristic model object. The paper examines the divergent component of evolutionary trajectory formation. As a result of the simulation, the dependence of the potential variability parameter on the position of the fitness function landscape was obtained. The simulation results are in agreement with the real data of molecular evolution experiments.

WOS
Держатели документа:
RAS, SB, Inst Biophys, Fed Res Ctr,Krasnoyarsk Sci Ctr, 50 Akad Gorodok, Krasnoyarsk 660036, Russia.
Siberian Fed Univ, 79 Svobodny Pr, Krasnoyarsk 660041, Russia.

Доп.точки доступа:
Bartsev, S.; Baturina, P.

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14.


   
    Bioluminescent Properties of Semi-Synthetic Obelin and Aequorin Activated by Coelenterazine Analogues with Modifications of C-2, C-6, and C-8 Substituents / E. V. Eremeeva, T. Y. Jiang, N. P. Malikova [et al.] // Int. J. Mol. Sci. - 2020. - Vol. 21, Is. 15. - Ст. 5446, DOI 10.3390/ijms21155446. - Cited References:50. - The reported study was funded by RFBR and NSFC according to the research project No. 20-54-53011 (E.V.E. and N.P.M.), Russian Foundation for Basic Research (No. 18-44-242001), Government of Krasnoyarsk Territory, Krasnoyarsk Regional Fund of Science (E.S.V.), the National Natural Science Foundation of China (No. 81874308), and the Shandong Natural Science Foundation (No. ZR2018ZC0233) (M.L.). . - ISSN 1422-0067
РУБ Biochemistry & Molecular Biology + Chemistry, Multidisciplinary
Рубрики:
CA2+-REGULATED PHOTOPROTEINS
   SPECTROSCOPIC PROPERTIES

Кл.слова (ненормированные):
photoprotein -- obelin -- aequorin -- coelenterazine -- analogues
Аннотация: Ca2+-regulated photoproteins responsible for bioluminescence of a variety of marine organisms are single-chain globular proteins within the inner cavity of which the oxygenated coelenterazine, 2-hydroperoxycoelenterazine, is tightly bound. Alongside with native coelenterazine, photoproteins can also use its synthetic analogues as substrates to produce flash-type bioluminescence. However, information on the effect of modifications of various groups of coelenterazine and amino acid environment of the protein active site on the bioluminescent properties of the corresponding semi-synthetic photoproteins is fragmentary and often controversial. In this paper, we investigated the specific bioluminescence activity, light emission spectra, stopped-flow kinetics and sensitivity to calcium of the semi-synthetic aequorins and obelins activated by novel coelenterazine analogues and the recently reported coelenterazine derivatives. Several semi-synthetic photoproteins activated by the studied coelenterazine analogues displayed sufficient bioluminescence activities accompanied by various changes in the spectral and kinetic properties as well as in calcium sensitivity. The poor activity of certain semi-synthetic photoproteins might be attributed to instability of some coelenterazine analogues in solution and low efficiency of 2-hydroperoxy adduct formation. In most cases, semi-synthetic obelins and aequorins displayed different properties upon being activated by the same coelenterazine analogue. The results indicated that the OH-group at the C-6 phenyl ring of coelenterazine is important for the photoprotein bioluminescence and that the hydrogen-bond network around the substituent in position 6 of the imidazopyrazinone core could be the reason of different bioluminescence activities of aequorin and obelin with certain coelenterazine analogues.

WOS
Держатели документа:
Krasnoyarsk Sci Ctr SB RAS, Inst Biophys SB RAS, Photobiol Lab, Fed Res Ctr, Krasnoyarsk 660036, Russia.
Shandong Univ, Sch Pharmaceut Sci, Dept Med Chem, Key Lab Chem Biol MOE, Jinan 250012, Peoples R China.
Shandong Univ, Helmholtz Inst Biotechnol, State Key Lab Microbial Technol, Qingdao 266237, Peoples R China.

Доп.точки доступа:
Eremeeva, Elena, V; Jiang, Tianyu; Malikova, Natalia P.; Li, Minyong; Vysotski, Eugene S.; RFBRRussian Foundation for Basic Research (RFBR); NSFCNational Natural Science Foundation of China (NSFC) [20-54-53011]; Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR) [18-44-242001]; Krasnoyarsk Regional Fund of Science; National Natural Science Foundation of ChinaNational Natural Science Foundation of China (NSFC) [81874308]; Shandong Natural Science FoundationNatural Science Foundation of Shandong Province [ZR2018ZC0233]; Government of Krasnoyarsk Territory

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15.


   
    Redquorinxs mutants with enhanced calcium sensitivity and bioluminescence output efficiently report cellular and neuronal network activities / A. Bakayan, S. Picaud, N. P. Malikova [et al.] // Int. J. Mol. Sci. - 2020. - Vol. 21, Is. 21. - Ст. 7846. - P1-22, DOI 10.3390/ijms21217846 . - ISSN 1661-6596
Кл.слова (ненормированные):
Aequorin -- Bioluminescence -- BRET -- Calcium sensor -- GPCR assay -- Mutagenesis -- Neuronal network imaging
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.

Scopus
Держатели документа:
Institut de Neurobiologie Alfred Fessard, UPR 3294, Centre National de la Recherche Scientifique (CNRS), Avenue de la Terrasse, Gif?sur?Yvette, 91198, France
BioEmergences Unit, CNRS USR 3695, Universite Paris?Saclay, Avenue de la Terrasse, Gif?sur?Yvette, 91198, France
Neuroscience Paris Seine ? Institut de Biologie Paris Seine (NPS ? IBPS), CNRS, UMR8246, INSERM U1130, Sorbonne Universite UM119, Paris, 75005, France
Photobiology Laboratory, Institute of Biophysics SB RAS, Federal Research Center “Krasnoyarsk Science Center SB RAS”, Krasnoyarsk, 660036, Russian Federation

Доп.точки доступа:
Bakayan, A.; Picaud, S.; Malikova, N. P.; Tricoire, L.; Lambolez, B.; Vysotski, E. S.; Peyrieras, N.

Найти похожие
16.


   
    Neural networks playing 'matching pennies' with each other: reproducibility of game dynamics / T. Dolgova, S. Bartsev // INTERNATIONAL WORKSHOP ADVANCED TECHNOLOGIES IN MATERIAL SCIENCE, : IOP PUBLISHING LTD, 2019. - Vol. 537: International Workshop on Advanced Technologies in Material Science, (APR 04-06, 2019, Krasnoyarsk, RUSSIA). - Ст. 042002. - (IOP Conference Series-Materials Science and Engineering), DOI 10.1088/1757-899X/537/4/042002. - Cited References:18 . -
РУБ Engineering, Mechanical + Materials Science, Multidisciplinary
Рубрики:
REPRESENTATIONS
   CONSCIOUSNESS

Аннотация: Reflection is an essential feature of consciousness and possibly the single most important one. This fact allows us to simplify the objective of the concept of 'neural correlates of consciousness' and to focus investigations on reflection itself. Reflexive games are the concentrated and pure embodiment of reflection manifestation without the addition of other higher cognitive functions. In this paper, we use the game 'matching pennies' ("Odd-Even") in order to trace the strategies and possible patterns of recurrent neural network operation. Experimental results show the splitting of all considered game patterns into two groups. A significant difference was observed in these groups of patterns, indicating a qualitative difference in game dynamics apparently due to the qualitatively different dynamic patterns of neuron excitations of the networks. A similar splitting of all players into two groups was found by other authors for human players, which differ in terms of the reflection availability. By this, we can assume that one of the causes of the splitting is that the presence of reflection in a particular group of recurrent neural networks dramatically changes the game meta-strategy.

WOS
Держатели документа:
Siberian Fed Univ, 79 Svobodny Pr, Krasnoyarsk 660041, Russia.
RAS, SB, Inst Biophys, Fed Res Ctr,Krasnoyarsk Sci Ctr, 50 Akad Gorodok, Krasnoyarsk 660036, Russia.

Доп.точки доступа:
Dolgova, T.; Bartsev, S.

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17.


   
    A heuristic neural network model in the research of properties of evolutionary trajectories / S. Bartsev, P. Baturina // IOP Conference Series: Materials Science and Engineering : Institute of Physics Publishing, 2019. - Vol. 537: International Workshop on Advanced Technologies in Material Science, Mechanical and Automation Engineering - MIP: Engineering-2019 (4 April 2019 through 6 April 2019, ) Conference code: 149243, Is. 4, DOI 10.1088/1757-899X/537/4/042001
Кл.слова (ненормированные):
Molecular biology -- Artificial networks -- Common property -- Evolving systems -- Fitness functions -- Heuristic model -- Molecular evolution -- Neural network model -- Trajectory formation -- Heuristic methods
Аннотация: There is considerable data on molecular evolution, but there remains no approach to systematizing them within the framework of the key problems of biology. To search for the most common properties of evolving systems, the heuristic method has been proposed. Artificial networks of formal neurons were chosen as the heuristic model object. The paper examines the divergent component of evolutionary trajectory formation. As a result of the simulation, the dependence of the potential variability parameter on the position of the fitness function landscape was obtained. The simulation results are in agreement with the real data of molecular evolution experiments. © Published under licence by IOP Publishing Ltd.

Scopus,
Смотреть статью
Держатели документа:
Institute of Biophysics SB RAS, Federal Research Center, Krasnoyarsk Scientific Center SB RAS, 50, Akademgorodok, Krasnoyarsk, 660036, Russian Federation
Siberian Federal University, 79 Svobodny pr., Krasnoyarsk, 660041, Russian Federation

Доп.точки доступа:
Bartsev, S.; Baturina, P.

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18.


   
    Picosecond Fluorescence Relaxation Spectroscopy of the Calcium-Discharged Photoproteins Aequorin and Obelin [Text] / B. . van Oort [et al.] // Biochemistry. - 2009. - Vol. 48, Is. 44. - P10486-10491, DOI 10.1021/bi901436m. - Cited References: 33. - This work was supported by NATO Collaborative Linkage Grant No 979229,Grants of SB RAS and RFBR 09-04-12-022, MCB program of RAS BvO was supported by 'Stichung voor Fundamenteel Onderzock der Materic (FOM)', which is financially supported by the NWO. and by I Rubicon grant of NWO E V E was supported by Wageningen University Sandwich Ph D-Fellowship program S P L was supported by Wageningen University Sandwich Ph D.-Fellowship program, European Community Marie Curie Research Training Network MRTN-CT-2005-019481 (From FLIM to FLIN), and Computational Science Gram 635 000 014 from the netherlands Organization for Scientific Research . - ISSN 0006-2960
РУБ Biochemistry & Molecular Biology
Рубрики:
CA2+-REGULATED PHOTOPROTEINS
   VIOLET BIOLUMINESCENCE

   ANGSTROM RESOLUTION

   RECOMBINANT OBELIN

   CRYSTAL-STRUCTURE

   W92F OBELIN

   COELENTERAZINE

   MECHANISM

   EXPRESSION

   PROTEINS

Аннотация: Addition of calcium tons to the Ca(2+)-regulated photoproteins, such its aequorin and obelin, produces it blue bioluminescence originating from fluorescence transition of the protein-bound product coelenteramide. The kinetics of several transient fluorescent species of the bound coelenteramide is resolved after picosecond-laser excitation and streak camera detection. The Initially formed spectral distributions at picosecond-times are broad, evidently comprised of two contributions, One at higher energy (similar to 25 000 cm(-1)) assigned as from the Ca(2+)-discharged photoprotein-bound coelenteramide in its neutral state. This component decays much more rapidly (t(1/2) similar to 2 ps) in the case of the Ca(2+)-discharged obelin than aequorin (t(1/2) similar to 30 ps). The Second component at lower energy shows several intermediates in the 150-500 ps miles. with it Final species having spectral maxima 19 400 cm(-1), bound to Ca(2+)-discharged obelin. and 2 1300 cm(-1), bound to Ca(2+)-discharged aequorin, and both have it fluorescence decay lifetime of 4 ns It is proposed that the rapid kinetics of these fluorescence transients oil the picosecond time scale, correspond to times For relaxation of the protein Structural environment of the binding cavity

Держатели документа:
[Lee, John] Univ Georgia, Dept Biochem & Mol Biol, Athens, GA 30602 USA
[van Oort, Bart
Koehorst, Rob B. M.
Laptenok, Sergey P.
van Amerongen, Herbert] Wageningen Univ, Biophys Lab, NL-6703 HA Wageningen, Netherlands
[Eremeeva, Elena V.
Laptenok, Sergey P.
van Berkel, Willem J. H.
Visser, Antonie J. W. G.] Wageningen Univ, Biochem Lab, NL-6703 HA Wageningen, Netherlands
[Koehorst, Rob B. M.
van Amerongen, Herbert
Visser, Antonie J. W. G.] Wageningen Univ, Microspect Ctr, NL-6703 HA Wageningen, Netherlands
[Eremeeva, Elena V.
Malikova, Natalia P.
Markova, Svetlana V.
Vysotski, Eugene S.] Russian Acad Sci, Inst Biophys, Photobiol Lab, Siberian Branch, Krasnoyarsk 660036, Russia
ИБФ СО РАН : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
van Oort, B...; Eremeeva, E.V.; Koehorst, RBM; Laptenok, S.P.; van Amerongen, H...; van Berkel, WJH; Malikova, N.P.; Markova, S.V.; Vysotski, E.S.; Visser, AJWG; Lee, J...; NATO Collaborative Linkage [979229]; RFBR [09-04-12-022]; 'Stichung voor Fundamenteel Onderzock der Materic (FOM)'; NWO; Wageningen University; European Community Marie Curie Research Training Network [MRTN-CT-2005-019481]; netherlands Organization [635 000 014]

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19.


   
    Violet bioluminescence and fast kinetics from W92F obelin: Structure-based proposals for the bioluminescence triggering and the identification of the emitting species [Text] / E. S. Vysotski [et al.] // Biochemistry. - 2003. - Vol. 42, Is. 20. - P6013-6024, DOI 10.1021/bi027258h. - Cited References: 45 . - ISSN 0006-2960
РУБ Biochemistry & Molecular Biology
Рубрики:
RAY CRYSTALLOGRAPHIC ANALYSIS
   PHOTOPROTEIN AEQUORIN

   ANGSTROM RESOLUTION

   RECOMBINANT OBELIN

   CALCIUM

   LUMINESCENCE

   LONGISSIMA

   EVOLUTION

   PROTEINS

   COELENTERAZINE

Аннотация: Obelin from the hydroid Obelia longissima and aequorin are members of a subfamily of Ca2+-regulated photoproteins that is a part of the larger EF-hand calcium binding protein family. On the addition of Ca2+, obelin generates a blue bioluminescence emission (lambda(max) = 485 nm) as the result of the oxidative decarboxylation of the bound substrate, coelenterazine. The W92F obelin mutant is noteworthy because of the unusually high speed with which it responds to sudden changes of [Ca2+] and because it emits violet light rather than blue due to a prominent band with lambda(max) = 405 nm. Increase of pH in the range from 5.5 to 8.5 and using D2O both diminish the contribution of the 405 nm band, indicating that excited state proton transfer is involved. Fluorescence model studies have suggested the origin of the 485 nm emission as the excited state of an anion of coelenteramide, the bioluminescence reaction product, and 405 nm from the excited neutral state. Assuming that the dimensions of the substrate binding cavity do not change during the excited state formation, a His22 residue within hydrogen bonding distance to the 6-(p-hydroxy)-phenyl group of the excited coelenteramide is a likely candidate for accepting the phenol proton to produce an ion-pair excited state, in support of recent suggestions for the bioluminescence emitting state. The proton transfer could be impeded by removal of the Trp92 H-bond, resulting in strong enhancement of a 405 nm band giving the violet color of bioluminescence. Comparative analysis of 3D structures of the wild-type (WT) and W92F obelins reveals that there are structural displacements of certain key Ca2+-ligating residues in the loops of the two C-terminal EF hands as well as clear differences in hydrogen bond networks in W92F. For instance, the hydrogen bond between the side-chain oxygen atom of Asp 169 and the main-chain nitrogen of Arg112 binds together the incoming alpha-helix of loop III and the exiting cc-helix of loop IV in WT, providing probably concerted changes in these EF hands on calcium binding. But this linkage is not found in W92F obelin. These differences apparently do not change the overall affinity to calcium of W92F obelin but may account for the kinetic differences between the WT and mutant obelins. From analysis of the hydrogen bond network in the coelenterazine binding cavity, it is proposed that the trigger for bioluminescence reaction in these Ca2+-regulated photoproteins may be a shift of the hydrogen bond donor-acceptor separations around the coelenterazine-2-hydroperoxy substrate, initiated by small spatial adjustment of the exiting a-helix of loop IV.

Держатели документа:
Univ Georgia, Dept Biochem & Mol Biol, Athens, GA 30602 USA
Univ Georgia, Dept Chem, Athens, GA USA
RAS, SB, Photobiol Lab, Inst Biophys, Krasnoyarsk, Russia
Univ Washington, Friday Harbor Labs, Seattle, WA 98195 USA
ИБФ СО РАН : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Vysotski, E.S.; Liu, Z.J.; Markova, S.V.; Blinks, J.R.; Deng, L...; Frank, L.A.; Herko, M...; Malikova, N.P.; Rose, J.P.; Wang, B.C.; Lee, J...

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20.


   
    Crystal structures of the F88Y obelin mutant before and after bioluminescence provide molecular insight into spectral tuning among hydromedusan photoproteins / P. V. Natashin [et al.] // FEBS J. - 2014. - Vol. 281, Is. 5. - P1432-1445, DOI 10.1111/febs.12715 . - ISSN 1742-4658
Кл.слова (ненормированные):
aequorin -- bioluminescence -- coelenterazine, obelin -- 6 (4 hydroxyphenyl) derivative -- aequorin -- benzene derivative -- calcium ion -- hydromedusan -- mutant protein -- obelin -- oxygen -- photoprotein -- unclassified drug -- amino acid substitution -- article -- bioluminescence -- calcium transport -- crystal structure -- fluorescence -- hydrogen bond -- priority journal -- protein conformation -- protein structure -- wild type -- Coelenterata -- aequorin -- bioluminescence -- Ca2+-regulated photoprotein -- coelenterazine, obelin -- Amino Acid Substitution -- Animals -- Conserved Sequence -- Crystallography, X-Ray -- Hydrogen Bonding -- Hydrozoa -- Luminescent Proteins -- Models, Molecular -- Mutagenesis, Site-Directed -- Mutant Proteins -- Protein Conformation -- Spectrophotometry
Аннотация: Ca2+-regulated photoproteins are responsible for the bioluminescence of a variety of marine coelenterates. All hydromedusan photoproteins are a single-chain polypeptide to which 2- hydroperoxycoelenterazine is tightly but non-covalently bound. Bioluminescence results from oxidative decarboxylation of 2-hydroperoxycoelenterazine, generating protein-bound coelenteramide in an excited state. The bioluminescence spectral maxima of recombinant photoproteins vary in the range 462-495 nm, despite a high degree of identity of amino acid sequences and spatial structures of these photoproteins. Based on studies of obelin and aequorin mutants with substitution of Phe to Tyr and Tyr to Phe, respectively [Stepanyuk GA et al. (2005) FEBS Lett 579, 1008-1014], it was suggested that the spectral differences may be accounted for by an additional hydrogen bond between the hydroxyl group of a Tyr residue and an oxygen atom of the 6-(p-hydroxyphenyl) substituent of coelenterazine. Here, we report the crystal structures of two conformation states of the F88Y obelin mutant that has bioluminescence and product fluorescence spectra resembling those of aequorin. Comparison of spatial structures of the F88Y obelin conformation states with those of wild-type obelin clearly shows that substitution of Phe to Tyr does not affect the overall structures of either F88Y obelin or its product following Ca2+ discharge, compared to the conformation states of wild-type obelin. The hydrogen bond network in F88Y obelin being due to the Tyr substitution clearly supports the suggestion that different hydrogen bond patterns near the oxygen of the 6-(p-hydroxyphenyl) substituent are the basis for spectral modifications between hydromedusan photoproteins. Comparison of spatial structures and the hydrogen bond network formed into the substrate-binding cavity of WT obelin, F88Y obelin, and aequorin clearly shows that the main cause determining different light emission colors of hydromedusan photoproteins is a different arrangement of the hydrogen-bond network near OH group of 6-(p-hydroxyphenyl) substituent of coelenterazine due to the presence of either Phe or Tyr residue. © 2014 FEBS.

Scopus
Держатели документа:
National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
Institute of Biophysics, Russian Academy of Sciences, Siberian Branch, Akademgorodok 50, Krasnoyarsk 660036, Russian Federation
Laboratory of Bioluminescence Biotechnology, Institute of Fundamental Biology and Biotechnology, Siberian Federal University, Russian Federation
Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
IHuman Institute, ShanghaiTech University, Shanghai, China : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Natashin, P.V.; Markova, S.V.; Lee, J.; Vysotski, E.S.; Liu, Z.-J.

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