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1.


   
    Predictive radioecological mathematical model of the Yenisei river / A. G. Degermendzhi, L. G. Kosolapova, V. M. Belolipetskij // Radiatsionnaya Biologiya. Radioekologiya. - 2002. - Vol. 42, Is. 4. - С. 433-439 . - ISSN 0869-8031
Кл.слова (ненормированные):
Cesium -- Contamination -- Mathematical models -- Phosphorus -- Radioisotopes -- River pollution -- Cesium 137 -- Phosphorus 32 -- Radioecology -- The Yenisei river -- Ecosystems -- Bacteria (microorganisms) -- fresh water -- article -- ecosystem -- pollutant -- Russian Federation -- theoretical model -- Ecosystem -- Fresh Water -- Models, Theoretical -- Radioactive Pollutants -- Russia
Аннотация: A one-dimensional mathematical model of the Yenisei river ecosystem including hydrological, ecosystem and radioecologicl blocks has been developed. The model was used to evaluate contribution of different processes (transfer by water masses, dilution, radioactive decay, bioaccumulation) into self-purification of the river water from a radiation pollution. The pollution density of ecosystem components (bacteria, phyto-, zooplankton, phyto-, zoobenthos, detritus) with 137Cs and 32P is calculated.

Scopus
Держатели документа:
Inst. of Biophysics, Siberian Branch, RAS, Akademgorodok, Krasnoyarsk, 660036, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Degermendzhi, A.G.; Kosolapova, L.G.; Belolipetskij, V.M.

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2.


   
    Influence of excitation light intensity and leaf age on the slow chlorophyll fluorescence transient in radish / T. V. Nesterenko, A. A. Tikhomirov, V. N. Shikhov // Biophysics (Russian Federation). - 2012. - Vol. 57, Is. 4. - P464-468, DOI 10.1134/S0006350912040136 . - ISSN 0006-3509
Кл.слова (ненормированные):
leaf ontogeny -- light dependence -- slow fluorescence induction -- temporal indices -- Raphanus sativus
Аннотация: The temporal characteristics of the slow phase of chlorophyll fluorescence induction-T0. 5 (half-decay time) and tmin (an integral-based index of the variable emission rate)-as well as the popular amplitude index FP/FS were determined at different excitation light intensities (Iex [400-500 nm] of 20-80 W/m2) in dark-adapted leaves of different age (3-24 days) taken from radish plants grown under continuous light of 100 W/m2 PAR. All the profiles thus obtained were mutually consistent, and the age-related variations were minimized at Iex > 40 W/m2; at that the age-averaged temporal indices proved to be more light-responsive than the standard amplitude ratio. В© 2012 Pleiades Publishing, Ltd.

Scopus
Держатели документа:
Institute of Biophysics, Siberian Branch, Russian Academy of Sciences, Akademgorodok, Krasnoyarsk 660036, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Nesterenko, T.V.; Tikhomirov, A.A.; Shikhov, V.N.

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3.


   
    Biological and physicochemical methods for utilization of plant wastes and human exometabolites for increasing internal cycling and closure of life support systems / I. G. Zolotukhin [et al.] // Advances in Space Research. - 2005. - Vol. 35, Is. 9 SPEC. ISS. - P1559-1562, DOI 10.1016/j.asr.2005.01.006 . - ISSN 0273-1177
Кл.слова (ненормированные):
BLSS -- Desalting -- Higher plants -- NaCl utilization -- SLS -- Biomass -- Crops -- Decomposition -- Electrodialysis -- Harvesting -- Metabolites -- Soils -- Wastes -- BLSS -- Higher plants -- NaCl utilization -- SLS -- Plants (botany) -- Biomass -- Decay -- Deionization -- Harvesting -- Plants -- Soil -- Wastes -- Wheat -- sodium chloride -- article -- biomass -- bioremediation -- culture medium -- feces -- growth, development and aging -- human -- metabolism -- methodology -- microbiology -- microclimate -- urine -- waste management -- wheat -- Biodegradation, Environmental -- Biomass -- Culture Media -- Ecological Systems, Closed -- Feces -- Humans -- Life Support Systems -- Sodium Chloride -- Soil Microbiology -- Triticum -- Urine -- Waste Management
Аннотация: Wheat was cultivated on soil-like substrate (SLS) produced by the action of worms and microflora from the inedible biomass of wheat. After the growth of the wheat crop, the inedible biomass was restored in SLS and exposed to decomposition ("biological" combustion) and its mineral compounds were assimilated by plants. Grain was returned to the SLS in the amount equivalent to human solid waste produced by consumption of the grain. Human wastes (urine and feces) after physicochemical processing turned into mineralized form (mineralized urine and mineralized feces) and entered the plants' nutrient solution amounts equal to average daily production. Periodically (once every 60-70 days) the nutrient solution was partly (up to 50%) desalinated by electrodialysis. Due to this NaCl concentration in the nutrient solution was sustained at a fixed level of about 0.26%. The salt concentrate obtained could be used in the human nutrition through NaCl extraction and the residuary elements were returned through the mineralized human liquid wastes into matter turnover. The control wheat cultivation was carried out on peat with use of the Knop nutrient solution. Serial cultivation of several wheat vegetations within 280 days was conducted during the experiment. Grain output varied and yield/harvest depended, in large part, upon the amount of inedible biomass returned to SLS and the speed of its decomposition. After achieving a stationary regime, (when the quantity of wheat inedible biomass utilized during vegetation in SLS is equal to the quantity of biomass introduced into SLS before vegetation) grain harvest in comparison with the control was at most 30% less, and in some cases was comparable to the control harvest values. The investigations carried out on the wheat example demonstrated in principle the possibility of long-term functioning of the LSS photosynthesizing link based on optimizations of biological and physicochemical methods of utilization of the human and plants wastes. The possibilities for the use of these technologies for the creation integrated biological-physicochemical LSS with high closure degree of internal matter turnover are discussed in this paper. В© 2005 Published by Elsevier Ltd on behalf of COSPAR.

Scopus
Держатели документа:
Institute of Biophysics, Russian Academy of Sciences, Siberian Branch, Akademgorodok, Krasnoyarsk 660036, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Zolotukhin, I.G.; Tikhomirov, A.A.; Kudenko, Yu.A.; Gribovskaya, I.V.

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4.


   
    PHYSICOCHEMICAL PROPERTIES OF A PHOTOPROTEIN FROM THE HYDROID POLYP OBELIA-LONGISSIMA [Text] / V. S. BONDAR, K. P. TROFIMOV, E. S. VYSOTSKII // Biochem.-Moscow. - 1992. - Vol. 57, Is. 10. - P1020-1027. - Cited References: 36 . - 8. - ISSN 0006-2979
РУБ Biochemistry & Molecular Biology
Рубрики:
CALCIUM-ACTIVATED PHOTOPROTEINS
   CTENOPHORES MNEMIOPSIS SP

   BEROE-OVATA

   AEQUORIN

   CA-2+

   INDICATORS

   PROTEIN

   BINDING

   PURIFICATION

   EXTRACTION

Кл.слова (ненормированные):
BIOLUMINESCENCE -- CA2+-ACTIVATED PHOTOPROTEIN -- OBELIN -- CHROMATOGRAPHY -- CALCIUM
Аннотация: The photoprotein obelin was isolated and purified to homogeneity (as indicated by sodium dodecyl sulfate polyacrylamide gel electrophoresis) from hydroids of Obelia longissima by gel filtration on Sephadex G-75 fine, ion exchange chromatography on Polysil CA-300 (10 mum), hydrophobic chromatography on Phenyl-Sepharose CL-4B, gel filtration on Sephacryl S-200 superfine, ion exchange chromatography on a Mono Q column at pH 7.0, chromatofocusing on a Mono P column (pH gradient 6.0-4.0), and ion exchange chromatography on a Mono Q column at pH 5.5, 8.8, and 7.0. The molecular weight of the native protein was 30 kD, and that measured in the presence of SDS was 19.8 kD. The specific activity of obelin is 4.9.10(15) quanta/mg protein, pseudo-first-order constant of bioluminescence decay 4 sec-1, and quantum yield 0.16 The range of measurable Ca2+ concentrations is 10(-7) to 10(-5) M. The luminescence spectrum of obelin peaks at 469 nm, and the fluorescence emission maximum of the discharged protein is at 455 nm. The optimum pH for luminescence is between 9.0 and 10.5. The molecular ionization constants are pK1 6.8 and pK2 12.2, and the ionization constants for the active site are pK1 9.1 and pK2 10.2
: 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
BONDAR, V.S.; TROFIMOV, K.P.; VYSOTSKII, E.S.

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5.


   
    EFFECT OF TEMPERATURE ON ACTIVITY AND STABILITY OF OBELIN [Text] / V. S. BONDAR [et al.] // Biochem.-Moscow. - 1992. - Vol. 57, Is. 7. - P717-724. - Cited References: 15 . - 8. - ISSN 0006-2979
РУБ Biochemistry & Molecular Biology
Рубрики:
CA-2+
   PHOTOPROTEINS

   INDICATORS

Кл.слова (ненормированные):
PHOTOPROTEINS -- OBELIN -- ACTIVATION ENERGY -- THERMOINACTIVATION -- THERMOSTABILITY
Аннотация: The temperature dependence of bioluminescent activity of the Ca2+-activated photoprotein obelin from the hydroid polyp Obelia longissima and thermoinactivation of this protein at different concentrations of (NH4)2SO4 have been studied. The maximal intensity of luminescence of obelin was observed at 4-15-degrees-C. The activity of the photoprotein is completely stable to storage for 3 days at room temperature. Increasing the temperature to 40-degrees-C resulted in a 25-30% loss of enzyme activity in 1 h. The presence of ammonium sulfate during heating stabilizes the activity of obelin. Two breaks, at 11 +/- 3-degrees-C and 47 +/- 3-degrees-C, are observed in the Arrhenius plot of the first-order rate constant of the luminescence decay. The bioluminescent curves of obelin are biphasic in the temperature range 10-40-degrees-C. It is assumed that obelin may exist in two kinetically distinct conformers (active and inactive) whose ratio is temperature dependent.
: 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
BONDAR, V.S.; TROFIMOV, K.P.; SANDALOV, T.P.; VYSOTSKII, E.S.

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6.


   
    MN2+-ACTIVATED LUMINESCENCE OF THE PHOTOPROTEIN OBELIN [Text] / E. S. VYSOTSKI [et al.] // Arch. Biochem. Biophys. - 1995. - Vol. 316, Is. 1. - P92-99, DOI 10.1006/abbi.1995.1014. - Cited References: 38 . - 8. - ISSN 0003-9861
РУБ Biochemistry & Molecular Biology + Biophysics
Рубрики:
CALCIUM-ACTIVATED PHOTOPROTEINS
   CTENOPHORES MNEMIOPSIS SP

   CA-2+-ACTIVATED PHOTOPROTEIN

   MESSENGER-RNA

   BEROE-OVATA

   AEQUORIN

   PURIFICATION

   PROTEIN

   CDNA

   EXTRACTION

Аннотация: The light emission of obelin may be initiated by Mn2+ under alkaline conditions. The luminescence takes place in a pH range from 7 to 12 with a sharp optimum at 11.75. The first-order rate constant for Mn2+-activated luminescence decay is more than 9 s(-1), while that for Ca2+-activated luminescence decay is only 6.9 s(-1). The Mn2+ concentration-effect curve for obelin determined with simple dilutions of manganese salt is a sigmoid curve, The slope of the curve is moderately dependent on the pH and was not more than 1 within the pH range tested. The maximal light emission, which is initiated by 3.6 X 10(-5) M Mn2+ at pH 11.75 was about 10% of the maximal Ca2+-activated luminescence. Mg2+ ions inhibit the Mn2+-activated luminescence of obelin. The addition of OH. and O-2(-) scavengers did not influence the Mn2+-activated luminescence, but when singlet oxygen quenchers were added, the Mn2+-dependent light emission was inhibited. This suggests that the O-1(2) might be formed and itself be responsible for chromophore oxidation attended with light emission. NEM and Na2S2O4 inhibit the Mn2+-initiated light emission of obelin completely, showing that endogenous hydroperoxide and SH-group(s) of the photoprotein are essential for both Ca2+-activated and Mn2+-activated light emission of obelin. (C) 1995 Academic Press, Inc.
: 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
VYSOTSKI, E.S.; TROFIMOV, C.P.; BONDAR, V.S.; FRANK, L.A.; MARKOVA, S.V.; ILLARIONOV, B.A.

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7.


   
    Green-Fluorescent Protein from the Bioluminescent Jellyfish Clytia gregaria Is an Obligate Dimer and Does Not Form a Stable Complex with the Ca2+-Discharged Photoprotein Clytin [Text] / N. P. Malikova [et al.] // Biochemistry. - 2011. - Vol. 50, Is. 20. - P4232-4241, DOI 10.1021/bi101671p. - Cited References: 50. - This work was supported by NATO Collaborative Linkage Grant 979229, Grants SB RAS No. 2 and RFBR 08-04-92209, 09-04-12022, and 09-04-00172, the MCB program of the Russian Academy of Sciences, and Bayer AG. . - ISSN 0006-2960
РУБ Biochemistry & Molecular Biology
Рубрики:
VIBRIO-FISCHERI Y1
   ENERGY-TRANSFER

   CORRELATION SPECTROSCOPY

   BACTERIAL LUCIFERASE

   REFRACTIVE-INDEX

   PHOTOBACTERIUM-LEIOGNATHI

   POLARIZED FLUORESCENCE

   EXCITATION TRANSFER

   RECOMBINANT OBELIN

   LUMAZINE PROTEIN

Аннотация: Green-fluorescent protein (GFP) is the origin of the green bioluminescence color exhibited by several marine hydrozoans and anthozoans. The mechanism is believed to be Forster resonance energy transfer (FRET) within a luciferase GFP or photoprotein-GFP complex. As the effect is found in vitro at micromolar concentrations, for FRET to occur this complex must have an affinity in the micromolar range. We present here a fluorescence dynamics investigation of the recombinant bioluminescence proteins from the jellyfish Clytia gregaria, the photoprotein clytin in its Ca2+-discharged form that is highly fluorescent (lambda(max) = 506 nm) and its GFP (cgreGFP; lambda(max) = 500 nm). Ca2+-discharged clytin shows a predominant fluorescence lifetime of 5.7 ns, which is assigned to the final emitting state of the bioluminescence reaction product, coelenteramide anion, and a fluorescence anisotropy decay or rotational correlation time of 12 ns (20 degrees C), consistent with tight binding and rotation with the whole protein. A 34 ns correlation time combined with a translational diffusion constant and molecular brightness from fluorescence fluctuation spectroscopy all confirm that cgreGFP is an obligate dimer down to nanomolar concentrations. Within the dimer, the two chromophores have a coupled excited-state transition yielding fluorescence depolarization via FRET with a transfer correlation time of 0.5 ns. The 34 ns time of cgreGFP showed no change upon addition of a 1000-fold excess of Ca2+-discharged clytin, indicating no stable complexation below 0.2 mM. It is proposed that any bioluminescence FRET complex with micromolar affinity must be one formed transiently by the cgreGFP dimer with a short-lived (millisecond) intermediate in the clytin reaction pathway.

Держатели документа:
[Lee, John] Univ Georgia, Dept Biochem & Mol Biol, Athens, GA 30602 USA
[Malikova, Natalia P.
Vysotski, Eugene S.] Russian Acad Sci, Siberian Branch, Photobiol Lab, Inst Biophys, Krasnoyarsk 660036, Russia
[Visser, Nina V.
van Hoek, Arie] Wageningen Univ, Biophys Lab, NL-6703 HA Wageningen, Netherlands
[Visser, Antonie J. W. G.] Wageningen Univ, Biochem Lab, NL-6703 HA Wageningen, Netherlands
[Visser, Nina V.
van Hoek, Arie
Visser, Antonie J. W. G.] Wageningen Univ, Microspect Ctr, NL-6703 HA Wageningen, Netherlands
[Skakun, Victor V.] Belarusian State Univ, Dept Syst Anal, Minsk 220050, Byelarus
ИБФ СО РАН : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Malikova, N.P.; Visser, N.V.; van Hoek, A...; Skakun, V.V.; Vysotski, E.S.; Lee, J...; Visser, AJWG

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8.


   
    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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9.


   
    Properties of recombinant fluorescent proteins from Photobacterium leiognathi and their interaction with luciferase intermediates / V. N. Petushkov, B. G. Gibson, J. Lee // Biochemistry. - 1995. - Vol. 34, Is. 10. - P3300-3309 . - ISSN 0006-2960
Кл.слова (ненормированные):
luciferase -- recombinant protein -- article -- ligand binding -- nonhuman -- priority journal -- protein isolation -- protein protein interaction -- protein stability -- vibrionaceae -- Bacterial Proteins -- Binding Sites -- Carrier Proteins -- Circular Dichroism -- Flavin Mononucleotide -- Fluorescence Polarization -- Genes, Bacterial -- Kinetics -- Ligands -- Luciferase -- Luminescence -- Molecular Sequence Data -- Photobacterium -- Recombinant Proteins -- Spectrophotometry -- Support, U.S. Gov't, P.H.S. -- Photobacterium leiognathi -- Vibrionaceae
Аннотация: Ligand binding and luciferase interaction properties of the recombinant protein corresponding to the lumazine protein gene (EMBL X56534) of Photobacterium leiognathi have been determined by fluorescence dynamics, circular dichroism, gel filtration, and SDS-PAGE. Scatchard analysis of a fluorescence titration shows that the apoprotein possess one binding site, and at 30В°C the KdS (?M) are as follows: 6,7-dimethyl-8-ribityllumazine, 0.26; riboflavin, 0.53; and much more weakly bound FMN, 30. All holoproteins are highly fluorescent and have absorption spectra distinct from each other and from the free ligands. The longest wavelength absorption maxima are, respectively (nm, 2В°C), 420,463, and 458. Ligand binding produces no change in the far-UV circular dichroism; all have mean residual ellipticity at 210 nm of -6500 deg cm2 dmol-1, the same as the native protein. However, in the bioluminescence reaction only the lumazine holoprotein shows a bioluminescence effect. Fluorescence emission anisotropy decay was used to establish that none of these holoproteins complexed with native luciferase and that the lumazine protein alone formed a 1:1 complex with the luciferase hydroxyflavin fluorescent transient and the luciferase peroxyflavin intermediates, revealed by a dominant channel of anisotropy loss, with rotational correlation time of 2.5 ns, and attributed to excitation transfer from the luciferase flavin donor to the acceptor, the lumazine ligand. The complex stability was sufficient to allow its isolation by FPLC gel filtration and verification by SDS-PAGE. These methods also confirmed the absence of interaction of the holoflavoproteins.

Scopus
Держатели документа:
Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, United States
Institute of Biophysics, Academy of Sciences of Russia (Siberian Branch), 660036 Krasnoyarsk, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Petushkov, V.N.; Gibson, B.G.; Lee, J.

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10.


   
    Purification and characterization of flavoproteins and cytochromes from the yellow bioluminescence marine bacterium Vibrio fischeri strain Y1 / V. N. Petushkov, J. Lee // European Journal of Biochemistry. - 1997. - Vol. 245, Is. 3. - P790-796 . - ISSN 0014-2956
Кл.слова (ненормированные):
anisotropy -- lumazine protein -- Photobacterium -- thioredoxin reductase -- time-resolved fluorescence -- cytochrome -- flavoprotein -- article -- bioluminescence -- nonhuman -- priority journal -- protein analysis -- protein purification -- sea -- vibrio -- Amino Acid Sequence -- Bacterial Proteins -- Cytochromes -- Flavoproteins -- Molecular Sequence Data -- Sequence Alignment -- Vibrio -- Azotobacter -- Bacteria (microorganisms) -- Escherichia coli -- Haemophilus -- haemophilus influenza -- Murinae -- Negibacteria -- Photobacterium -- Photobacterium leiognathi -- Pseudomonas -- uncultured marine bacterium -- Vibrio fischeri
Аннотация: Several flavoproteins and cytochromes that occur as major components in extracts of the yellow bioluminescence Y1 strain of the murine bacterium Vibrio fischeri have been purified and characterized with respect to their mass (SDS/PAGE) and matrix-assisted laser-desorption/ionization MS), chromatographic properties, N-terminal sequence, and spectroscopy (absorption, fluorescence emission and anisotropy decay). The investigated proteins were as follows: yellow fluorescence protein (YFP) with bound riboflavin, FMN or 6,7-dimethyl-8-ribityllumazine; a blue fluorescence protein (BFP) with bound 6,7-dimethyl-8-ribityllumazine, riboflavin, or 6- methyl-7-oxo-ribityllumazine; thioredoxin reductase with FAD as ligand; and two c-type diheme cytochromes, c551 and c554. We present evidence that the riboflavin-bound YFP has an N-terminal sequence corresponding to that published for the dimeric YFP. We show that an equilibrium replacement of the riboflavin can be made with excess lumazine derivative and that lumazine- bound YFP has different bioluminescence properties to those of the lumazine protein from Photobacterium leiognathi. BFP is a different protein again, and in the bacterial lysate it occurs in multiple forms, ligated to either riboflavin, lumazine, or t he 7-oxolumazine derivative. The N-terminal sequence for BFP-shows similarities to those of the YFP proteins and to lumazine protein and riboflavin synthase from Photobacterium. BFP in any form has no bioluminescence or riboflavin-synthase activity. A 70-kDa fluorescent flavoprotein with FAD as ligand has an N-terminal sequence highly similar to those of thioredoxin reductases from Haemophilus influenza and Escherichia coli. Cytochrome contaminations in previous preparations of YFP have been removed and an identified as the two c-type cytochromes c551 and c554. Both inhibit the NADH-induced bioluminescence in the reductase/luciferase system with the luciferase from P. leiognathi and V. fischeri. The N-terminal amino acid sequence of the cytochrome (c551) corresponds to a diheme cytochrome c4. The spectral properties of c554 are similar to those of other c5 cytochromes, and both c554 and c551 have absorption spectra similar to those of the respective cytochromes from the gram-negative bacteria Pseudomonas and Azotobacter.

Scopus
Держатели документа:
Dept. of Biochem. and Molec. Biology, University of Georgia, Athens, GA, United States
Institute of Biophysics, Academy of Sciences of Russia, Krasnoyarsk, Russian Federation
Dept. of Biochem. and Molec. Biology, University of Georgia, Athens, GA 30602, United States : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Petushkov, V.N.; Lee, J.

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11.


   
    Interaction of Photobacterium leiognathi and Vibrio fischeri Y1 luciferases with fluorescent (antenna) proteins: Bioluminescence effects of the aliphatic additive / V. N. Petushkov [et al.] // Biochemistry. - 1996. - Vol. 35, Is. 37. - P12086-12093, DOI 10.1021/bi9608931 . - ISSN 0006-2960
Кл.слова (ненормированные):
luciferase -- anisotropy -- antenna -- article -- bioluminescence -- complex formation -- energy transfer -- enzyme active site -- enzyme kinetics -- nonhuman -- priority journal -- protein protein interaction -- spectroscopy -- vibrionaceae -- Bacterial Proteins -- Carrier Proteins -- Cloning, Molecular -- Dithionite -- Flavin Mononucleotide -- Kinetics -- Luciferases -- Luminescent Measurements -- Luminescent Proteins -- Models, Structural -- Photobacterium -- Protein Binding -- Protein Conformation -- Recombinant Proteins -- Spectrophotometry -- Vibrio -- Bacteria (microorganisms) -- Photobacterium -- Photobacterium leiognathi -- Vibrio fischeri -- Vibrionaceae
Аннотация: The kinetics of the bacterial bioluminescence reaction is altered in the presence of the fluorescent (antenna) proteins, lumazine protein (LumP) from Photobacterium or the yellow fluorescence proteins (YFP) having FMN or Rf bound, from Vibrio fischeri strain Y1. Depending on reaction conditions, the bioluminescence intensity and its decay rate may be either enhanced or strongly quenched in the presence of the fluorescent proteins. These effects can be simply explained on the basis of the same protein-protein complex model that accounts for the bioluminescence spectral shifts induced by these fluorescent proteins. In such a complex, where the fluorophore evidently is in proximity to the luciferase active site, it is expected that the on off rate of certain aliphatic components of the reaction should be altered with a consequent shift in the equilibria among the luciferase intermediates, as recently elaborated in a kinetic scheme. These aliphatic components are the bioluminescence reaction substrate, tetradecanal or other long-chain aldehyde, its carboxylic acid product, or dodecanol used as a stabilizer of the luciferase peroxyflavin. No evidence can be found for the protein- protein interaction in the absence of the aliphatic component.

Scopus
Держатели документа:
Department of Biochemistry, University of Georgia, Athens, GA 30602, United States
Institute of Biophysics, Acad. of Sci. of Russia, 660036 Krasnoyarsk, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Petushkov, V.N.; Ketelaars, M.; Gibson, B.G.; Lee, J.

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12.


   
    Interaction of Photobacterium leiognathi and Vibrio fischeri Y1 luciferases with fluorescent (Antenna) proteins: Bioluminescence effects of the aliphatic additive [Text] / V. N. Petushkov [et al.] // Biochemistry. - 1996. - Vol. 35, Is. 37. - P12086-12093, DOI 10.1021/bi9608931. - Cited References: 41 . - ISSN 0006-2960
РУБ Biochemistry & Molecular Biology
Рубрики:
BACTERIAL LUCIFERASE
   LUMAZINE PROTEIN

   FLAVIN INTERMEDIATE

   ANGSTROM RESOLUTION

   RIBOFLAVIN PROTEIN

   PURIFICATION

   MECHANISM

   EMISSION

   ALDEHYDE

   INHIBITION

Аннотация: The kinetics of the bacterial bioluminescence reaction is altered in the presence of the fluorescent (antenna) proteins, lumazine protein (LumP) from Photobacterium or the yellow fluorescence proteins (YFP) having FMN or Rf bound, from Vibrio fischeri strain Y1, Depending on reaction conditions, the bioluminescence intensity and its decay rate may be either enhanced or strongly quenched in the presence of the fluorescent proteins. These effects call be simply explained on the basis of the same protein-protein complex model that accounts for the bioluminescence spectral shifts induced by these fluorescent proteins. In such a complex, when the fluorophore evidently is in proximity to the luciferase active site, it is expected that the on-off rate of certain aliphatic components of the reaction should be altered with a consequent shift in the equilibria among the luciferase intermediates, as recently elaborated in a kinetic scheme, These aliphatic components are the bioluminescence reaction substrate, tetradecanal or other long-chain aldehyde, its carboxylic acid product, or dodecanol used as a stabilizer of the luciferase peroxyflavin. No evidence can be found or the protein-protein interaction in the absence of the aliphatic component.

Держатели документа:
UNIV GEORGIA,DEPT BIOCHEM & MOL BIOL,ATHENS,GA 30602
RUSSIAN ACAD SCI,INST BIOPHYS,SIBERIAN BRANCH,KRASNOYARSK 660036,RUSSIA
ИБФ СО РАН : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Petushkov, V.N.; Ketelaars, M...; Gibson, B.G.; Lee, J...

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13.


   
    Direct measurement of excitation transfer in the protein complex of bacterial luciferase hydroxyflavin and the associated yellow fluorescence proteins from Vibrio fischeri Y1 [Text] / V. N. Petushkov, B. G. Gibson, J. . Lee // Biochemistry. - 1996. - Vol. 35, Is. 25. - P8413-8418, DOI 10.1021/bi952691v. - Cited References: 24 . - ISSN 0006-2960
РУБ Biochemistry & Molecular Biology
Рубрики:
LUMAZINE PROTEIN
   LUMINOUS BACTERIUM

   STRAIN Y-1

   BIOLUMINESCENCE

   EMISSION

   PURIFICATION

   TRANSIENT

   LIGHT

Аннотация: Time-resolved fluorescence was used to directly measure the energy transfer rate constant in the protein-protein complex involved in the yellow bioluminescence of Vibrio fischeri, strain Y1. In this reaction the putative donor is the fluorescent transient intermediate, luciferase hydroxyflavin, which exhibits a major fluorescence lifetime of the bound flavin of 10 ns. On addition of the acceptor, the V. fischeri yellow fluorescence protein containing either FMN or riboflavin as ligand, a rapid decay time, 0.25 ns, becomes predominant. The same results are observed using rec-luciferase from Photobacterium leiognathi to produce the donor. Because of favorable spectral separation in this system, this rapid decay rate of 4 ns(-1), can be directly equated to the energy transfer rate. This rate is ten times higher than the rate previously observed in the Photobacterium luciferase hydroxyflavin-lumazine protein, donor-acceptor system, derived from emission anisotropy measurements. This ten-times ratio is close to the ratio of spectral overlaps of the donor fluorescence with the acceptor absorption, between these two systems, so it is concluded that the topology of the protein complexes in both cases, must be very similar. Energy transfer is also monitored by the loss of steady-state fluorescence intensity at 460 nm of the donor, on addition of the acceptor protein. A fluorescence titration indicates that luciferase hydroxyflavin and the yellow protein complex with a 1:1 stoichiometry with a K-d of 0.7 mu M (0 degrees C). These parameters account for the bioluminescence spectral shifting effects observed in these reactions.

Держатели документа:
UNIV GEORGIA,DEPT BIOCHEM & MOLEC BIOL,ATHENS,GA 30602
RUSSIAN ACAD SCI,INST BIOPHYS,SIBERIAN BRANCH,KRASNOYARSK 660036,RUSSIA
ИБФ СО РАН : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Petushkov, V.N.; Gibson, B.G.; Lee, J...

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14.


   
    Comparison of chronic low-dose effects of alpha- and beta-emitting radionuclides on marine bacteria / M. A. Selivanova [et al.] // Cent. Eur. J. Biol. - 2014. - Vol. 9, Is. 10. - P951-959, DOI 10.2478/s11535-014-0331-0 . - ISSN 1644-3632
Кл.слова (ненормированные):
Am-241 -- Hormesis -- Luminous bacteria -- Peroxides -- Radiotoxicity -- Tritium
Аннотация: Effects of Americium-241 (241Am), alpha-emitting radionuclide of high specific radioactivity, and tritium (3H), beta-emitting radionuclide, on luminous bacteria Photobacterium phosphoreum were compared. Bioluminescence intensity served as a marker of bacterial physiological activity. Three successive stages in the bioluminescence response to 241Am and 3H were found under conditions of lowdose irradiation: (1) absence of effects, (2) activation, and (3) inhibition. They were interpreted in terms of bacterial response to stressfactor as stress recognition, adaptive response/syndrome, and suppression of physiological function (i.e. radiation toxicity). Times of bioluminescence activation (TBA) and inhibition (TBI) were suggested as parameters to characterize hormesis and toxic stages in a course of chronic low-dose irradiation of the microorganisms. Values of TBA and TBI of 241Am were shorter than those of 3H, revealing higher impact of alpha-irradiation (as compared to beta-irradiation) under comparable radiation doses. Increases of peroxide concentration and NADH oxidation rates in 241Am aquatic solutions were demonstrated; these were not found in tritiated water. The results reveal a biological role of reactive oxygen species generated in water solutions as secondary products of the radioactive decay. The study provides a scientific basis for elaboration of bioluminescence-based assay to monitor radiotoxicity of alpha- and beta-emitting radionuclides in aquatic solutions. © 2014 Versita Warsaw and Springer-Verlag Wien.

Scopus
Держатели документа:
Institute of Biophysics SB RAS, 660036 Krasnoyarsk, Russian Federation
Siberian Federal University, 660041 Krasnoyarsk, Russian Federation
Siberian State Technological University, Lesosibirsk, Krasnoyarsk region, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Selivanova, M.A.; Rozhko, T.V.; Devyatlovskaya, A.N.; Kudryasheva, N.S.

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15.


   
    INACTIVATION OF BACTERIAL LUCIFERASES BY N-ETHYLMALEIMIDE [Text] / T. P. SANDALOVA, N. A. TYULKOVA // Biochem.-Moscow. - 1992. - Vol. 57, Is. 6. - P. 552-558. - Cited References: 21 . - ISSN 0006-2979
РУБ Biochemistry & Molecular Biology
Рубрики:
AMINO-ACID SEQUENCE
   NUCLEOTIDE-SEQUENCE

   REACTIVE SULFHYDRYL

   PHOTOBACTERIUM-LEIOGNATHI

   VIBRIO-HARVEYI

   BIOLUMINESCENCE

   SUBUNIT

   REGION

   GENE

Кл.слова (ненормированные):
LUCIFERASE -- N-ETHYLMALEIMIDE
Аннотация: The kinetics of inactivation of luciferases from four species of luminescent bacteria by the thiol reagent N-ethylmaleimide were investigated The dependencies of inactivation on ionic strength differed among the enzymes. Increasing the molarity of the buffer increased the rate of inactivation of all luciferases except that of Vibrio harveyi. Modification of Photobacterium phosphoreum luciferase decreased the maximal intensity of bioluminescence, whereas modification of Photobacterium leiognathi and Vibrio fischeri luciferases in high ionic strength buffers decreased the maximal intensity of bioluminescence and changed the luminescence decay rate constant. High ionic strength apparently alters the conformational states of the luciferases.

WOS : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
SANDALOVA, T.P.; TYULKOVA, N.A.

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16.


   
    Interaction of aromatic compounds with Photobacterium leiognathi luciferase: fluorescence anisotropy study [Text] / N. S. Kudryasheva [et al.] // Luminescence. - 2003. - Vol. 18, Is. 3. - P. 156-161, DOI 10.1002/bio.719. - Cited References: 25 . - ISSN 1522-7235
РУБ Biochemistry & Molecular Biology
Рубрики:
ELECTRON-EXCITED-STATES
   BACTERIAL BIOLUMINESCENCE

   LUMAZINE PROTEIN

   MECHANISM

Кл.слова (ненормированные):
bioluminescence -- luciferase -- fluorescent compounds -- anisotropy decay
Аннотация: The time-resolved and steady-state fluorescence techniques,were employed to elucidate possible interactions of four aromatic compounds (anthracene, POPOP, MSB and 1,4-naphthalendiol) with bacterial luciferase. Fluorescence spectra and fluorescence anisotropy decays of these compounds were studied in ethanol, water-ethanol solutions and in the presence of bacterial luciferase. Shifts of fluorescent spectra and differences in rotational correlation times are interpreted in terms of weak (hydrophobic) interactions of the molecules with the enzyme. These interactions suggest the feasibility of intermolecular energy transfer by an exchange resonance mechanism with a collision-interaction radius as a way of excitation of these compounds in the reaction catalysed by bacterial luciferase. Copyright (C) 2003 John Wiley Sons, Ltd.

WOS
Держатели документа:
Russian Acad Sci SB, Inst Biophys, Krasnoyarsk 660036, Russia
Univ Agr, Dept Biochem, Wageningen, Netherlands
ИБФ СО РАН : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Kudryasheva, N.S.; Nemtseva, E.V.; Visser, AJWG; van Hoek, A...

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17.


   
    Effect of low-dose ionizing radiation on luminous marine bacteria: radiation hormesis and toxicity [Text] / N. S. Kudryasheva, T. V. Rozhko // J. Environ. Radioact. - 2015. - Vol. 142. - P68-77, DOI 10.1016/j.jenvrad.2015.01.012. - Cited References:131. - This work was supported by the Russian Foundation for Basic Research, Grant No.13-04-01305a, the Program "Molecular and Cellular Biology" of the Russian Academy of Sciences, project VI 57.1.1. The part of the work (review of effects of americium-241) was supported by the Russian Science Foundation, Grant No. 14-14-00076. . - ISSN 0265-931X. - ISSN 1879-1700
РУБ Environmental Sciences
Рубрики:
RECOMBINANT LUMINESCENT MICROORGANISMS
   PHOTOBACTERIUM-LEIOGNATHI

Кл.слова (ненормированные):
Marine bacteria -- Low-dose effects -- Radiation hormesis -- Radiotoxicity -- Reactive oxygen species
Аннотация: The paper summarizes studies of effects of alpha- and beta-emitting radionuclides (americium-241, uranium-235+238, and tritium) on marine microorganisms under conditions of chronic low-dose irradiation in aqueous media. Luminous marine bacteria were chosen as an example of these microorganisms; bioluminescent intensity was used as a tested physiological parameter. Non-linear dose-effect dependence was demonstrated. Three successive stages in the bioluminescent response to americium-241 and tritium were found: 1 - absence of effects (stress recognition), 2 - activation (adaptive response), and 3 - inhibition (suppression of physiological function, i.e. radiation toxicity). The effects were attributed to radiation hormesis phenomenon. Biological role of reactive oxygen species, secondary products of the radioactive decay, is discussed. The study suggests an approach to evaluation of non-toxic and toxic stages under conditions of chronic radioactive exposure. (C) 2015 Elsevier Ltd. All rights reserved.

WOS
Держатели документа:
Inst Biophys SB RAS, Krasnoyarsk 660036, Russia
Siberian Fed Univ, Krasnoyarsk 660041, Russia
Krasnoyarsk State Med Acad, Krasnoyarsk 660022, Russia

Доп.точки доступа:
Kudryasheva, N. S.; Rozhko, T. V.; Russian Foundation for Basic Research [13-04-01305a]; Program "Molecular and Cellular Biology" of the Russian Academy of Sciences [VI 57.1.1]; Russian Science Foundation [14-14-00076]

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18.


   
    A continual model of soil organic matter transformations based on a scale of transformation rate [Text] / S. I. Bartsev, A. A. Pochekutov // Ecol. Model. - 2015. - Vol. 302. - P25-28, DOI 10.1016/j.ecolmodel.2015.01.030. - Cited References:18. - This work is supported by Basic Research Program of the Presidium of RAS Project No. 12 and Integration Project of SB RAS No. 21. . - ISSN 0304-3800. - ISSN 1872-7026
РУБ Ecology
Рубрики:
CARBON
   DECOMPOSITION

   DYNAMICS

   NITROGEN

   DECAY

Кл.слова (ненормированные):
Soil organic matter -- Continual model of soil -- Soil formation
Аннотация: The study proposes a model of transformation and decomposition of soil organic matter, based on using the rate of matter transformation as a continual scale of its transformation degree. The model is represented by one partial derivative differential equation that has an analytical solution. This model has only two adjustable parameters, while the number of experimentally determined parameters depends on how detailed the description of the plant litter is supposed to be. The model has been tested, and model parameters have been evaluated by comparing model predictions with the literature data on the stock of soil organic matter in different types of ecosystems. (C) 2015 Elsevier B.V. All rights reserved.

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Scopus
Держатели документа:
Inst Biophys SB RAS, Krasnoyarsk, Russia
Siberian Fed Univ, Inst Fundamental Biol & Biotechnol, Krasnoyarsk, Russia

Доп.точки доступа:
Bartsev, Sergey I.; Pochekutov, Aleksei A.; Basic Research Program of the Presidium of RAS Project [12]; Integration Project of SB RAS [21]

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19.


   
    Similarity of decay-associated spectra for tryptophan fluorescence of proteins with different structures / E. V. Nemtseva, O. O. Lashchuk, M. A. Gerasimova // Biophysics. - 2016. - Vol. 61, Is. 2. - P193-199, DOI 10.1134/S0006350916020111 . - ISSN 0006-3509
Кл.слова (ненормированные):
denaturation -- dielectric relaxation -- fluorescence lifetime -- tertiary protein structure -- tryptophan
Аннотация: Tryptophan fluorescence lifetimes were analyzed for three proteins: human serum albumin, bovine serum albumin, and bacterial luciferase, which contain one, two, and seven tryptophan residues, respectively. For all of the proteins, the fluorescence decays were fitted by three lifetimes: ?1 = 6–7 ns, ?2 = 2.0–2.3 ns, and ?3 ? 0.1 ns (the native state), and ?1 = 4.4–4.6 ns, ?2 = 1.7–1.8 ns, and ?3 ? 0.1 ns (the denatured state). Corresponding decay-associated spectra had similar peak wavelengths and spectrum half-widths both in the native state (??1max = 342 nm, ??2max = 328 nm, and ??3max = 315 nm), and in the denatured state (??1max = 350 nm, ??2max= 343 nm, and ??3max= 317 nm). The differences in the steady-state spectra of the studied proteins were accounted for the individual ratio of the lifetime component contributions. The lifetime components were compared with a classification of tryptophan residues in the structure of these proteins within the discrete states model. © 2016, Pleiades Publishing, Inc.

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Держатели документа:
Siberian Federal University, Svobodnyi pr. 79, Krasnoyarsk, Russian Federation
Institute of Biophysics, Siberian Branch, Russian Academy of Sciences, Akademgorodok 50/50, Krasnoyarsk, Russian Federation

Доп.точки доступа:
Nemtseva, E. V.; Lashchuk, O. O.; Gerasimova, M. A.

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20.


   
    Structural distinctions of fast and slow bacterial luciferases revealed by phylogenetic analysis [Text] / A. A. Deeva [et al.] // Bioinformatics. - 2016. - Vol. 32, Is. 20. - P3053-3057, DOI 10.1093/bioinformatics/btw386. - Cited References:31. - The reported study was partially funded by RFBR according to the research project No. 16-34-00746 mol_a; by the Ministry of Education and Science of the Russian Federation [project No 1762] and by the state budget allocated to the fundamental research at the Russian Academy of Sciences [project No 01201351504]. . - ISSN 1367-4803. - ISSN 1460-2059
РУБ Biochemical Research Methods + Biotechnology & Applied Microbiology

Аннотация: Motivation: Bacterial luciferases are heterodimeric enzymes that catalyze a chemical reaction, so called bioluminescence, which causes light emission in bacteria. Bioluminescence is vastly used as a reporter system in research tools and commercial developments. However, the details of the mechanisms that stabilize and transform the reaction intermediates as well as differences in the enzymatic kinetics amongst different bacterial luciferases remain to be elucidated. Results: Amino acid sequences alignments for 21 bacterial luciferases (both alpha- and beta-subunits) were analyzed. For alpha-subunit, containing the enzyme active center, 48 polymorphic amino acid positions were identified. According to them, the sequences fell into two distinct groups known as slow and fast based on the decay rate of the bioluminescence reaction. The differences in the enzyme active site induced by structural polymorphism are analyzed.

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Смотреть статью,
Scopus
Держатели документа:
Siberian Fed Univ, Lab Bioluminescent Biotechnol, Krasnoyarsk, Russia.
Inst Cell Biophys RAS, Mech Cell Genome Functioning Lab, Pushchino, Moscow Region, Russia.
Moscow Inst Phys & Technol, Dolgoprudnyi, Russia.
Inst Biophys SB RAS, Lab Photobiol, Krasnoyarsk, Russia.

Доп.точки доступа:
Deeva, Anna A.; Temlyakova, Evgenia A.; Sorokin, Anatoly A.; Nemtseva, Elena V.; Kratasyuk, Valentina A.; RFBR [16-34-00746 mol_a]; Ministry of Education and Science of the Russian Federation [1762]; state budget allocated to the fundamental research at Russian Academy of Sciences [01201351504]

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