WorldWideScience

Sample records for adenine

  1. Bound anionic states of adenine

    Energy Technology Data Exchange (ETDEWEB)

    Haranczyk, Maciej; Gutowski, Maciej S; Li, Xiang; Bowen, Kit H

    2007-03-20

    Anionic states of nucleic acid bases are involved in DNA damage by low-energy electrons and in charge transfer through DNA. Previous gas phase studies of free, unsolvated nucleic acid base parent anions probed only dipole-bound states, which are not present in condensed phase environments, but did not observe valence anionic states, which for purine bases, are thought to be adiabatically unbound. Contrary to this expectation, we have demonstrated that some thus far ignored tautomers of adenine, which result from enamine-imine transformations, support valence anionic states with electron vertical detachment energies as large as 2.2 eV, and at least one of these anionic tautomers is adiabatically bound. Moreover, we predict that the new anionic tautomers should also dominate in solutions and should be characterized by larger values of electron vertical detachment energy than the canonical valence anion. All of the new-found anionic tautomers might be formed in the course of dissociative electron attachment followed by a hydrogen atom attachment to a carbon atom, and they might affect the structure and properties of DNA and RNA exposed to low-energy electrons. The discovery of these valence anionic states of adenine was facilitated by the development of: (i) a new experimental method for preparing parent anions of nucleic acid bases for photoelectron experiments, and (ii) a new combinatorial/ quantum chemical approach for identification of the most stable tautomers of organic molecules. The computational portion of this work was supported by the: (i) Polish State Committee for Scientific Research (KBN) Grants: DS/8000-4-0140-7 (M.G.) and N204 127 31/2963 (M.H.), (ii) European Social Funds (EFS) ZPORR/2.22/II/2.6/ARP/U/2/05 (M.H.), and (iii) US DOE Office of Biological and Environmental Research, Low Dose Radiation Research Program (M.G.). M.H. holds the Foundation for Polish Science (FNP) award for young scientists. The calculations were performed at the Academic

  2. Adenine auxotrophy--be aware: some effects of adenine auxotrophy in Saccharomyces cerevisiae strain W303-1A.

    Science.gov (United States)

    Kokina, Agnese; Kibilds, Juris; Liepins, Janis

    2014-08-01

    Adenine auxotrophy is a commonly used genetic marker in haploid yeast strains. Strain W303-1A, which carries the ade2-1 mutation, is widely used in physiological and genetic research. Yeast extract-based rich medium contains a low level of adenine, so that adenine is often depleted before glucose. This could affect the cell physiology of adenine auxotrophs grown in rich medium. The aim of our study was to assess the effects of adenine auxotrophy on cell morphology and stress physiology. Our results show that adenine depletion halts cell division, but that culture optical density continues to increase due to cell swelling. Accumulation of trehalose and a coincident 10-fold increase in desiccation stress tolerance is observed in adenine auxotrophs after adenine depletion, when compared to prototrophs. Under adenine starvation, long-term survival of W303-1A is lower than during carbon starvation, but higher than during leucine starvation. We observed drastic adenine-dependent changes in cell stress physiology, suggesting that results may be biased when adenine auxotrophs are grown in rich media without adenine supplementation.

  3. Graphene-Enhanced Raman Scattering from the Adenine Molecules

    Science.gov (United States)

    Dolgov, Leonid; Pidhirnyi, Denys; Dovbeshko, Galyna; Lebedieva, Tetiana; Kiisk, Valter; Heinsalu, Siim; Lange, Sven; Jaaniso, Raivo; Sildos, Ilmo

    2016-04-01

    An enhanced Raman scattering from a thin layer of adenine molecules deposited on graphene substrate was detected. The value of enhancement depends on the photon energy of the exciting light. The benzene ring in the structure of adenine molecule suggests π-stacking of adenine molecule on top of graphene. So, it is proposed that the enhancement in the adenine Raman signal is explained by the resonance electron transfer from the Fermi level of graphene to the lowest unoccupied molecular orbital (LUMO) level of adenine.

  4. Graphene-Enhanced Raman Scattering from the Adenine Molecules.

    Science.gov (United States)

    Dolgov, Leonid; Pidhirnyi, Denys; Dovbeshko, Galyna; Lebedieva, Tetiana; Kiisk, Valter; Heinsalu, Siim; Lange, Sven; Jaaniso, Raivo; Sildos, Ilmo

    2016-12-01

    An enhanced Raman scattering from a thin layer of adenine molecules deposited on graphene substrate was detected. The value of enhancement depends on the photon energy of the exciting light. The benzene ring in the structure of adenine molecule suggests π-stacking of adenine molecule on top of graphene. So, it is proposed that the enhancement in the adenine Raman signal is explained by the resonance electron transfer from the Fermi level of graphene to the lowest unoccupied molecular orbital (LUMO) level of adenine. PMID:27075339

  5. Mitochondrial Adenine Nucleotide Transport and Cardioprotection

    OpenAIRE

    Das, Samarjit; Steenbergen, Charles

    2011-01-01

    Mitochondria are highly metabolically active cell organelles that not only act as the powerhouse of the cell by supplying energy through ATP production, but also play a destructive role by initiating cell death pathways. Growing evidence recognizes that mitochondrial dysfunction is one of the major causes of cardiovascular disease. Under de-energized conditions, slowing of adenine nucleotide transport in and out of the mitochondria significantly attenuates myocardial ischemia-reperfusion inju...

  6. Influence of Magnetic Microparticles Isolation on Adenine Homonucleotides Structure

    Directory of Open Access Journals (Sweden)

    Monika Kremplova

    2014-02-01

    Full Text Available The electroactivity of purine and pyrimidine bases is the most important property of nucleic acids that is very useful for determining oligonucleotides using square wave voltammetry. This study was focused on the electrochemical behavior of adenine-containing oligonucleotides before and after their isolation using paramagnetic particles. Two peaks were detected—peak A related to the reduction of adenine base and another peak B involved in the interactions between individual adenine strands and contributes to the formation of various spatial structures. The influence of the number of adenine bases in the strand in the isolation process using paramagnetic particles was investigated too.

  7. What is adenine doing in photolyase?

    Science.gov (United States)

    Acocella, Angela; Jones, Garth A; Zerbetto, Francesco

    2010-03-25

    The short answer to the title question is that it acts as an electrostatic bouncer that shoves the charge flow from flavin toward the DNA lesion that photolyase repairs. This explanation is provided by an explicit time-dependent quantum mechanical approach, which is used to investigate the electron transfer process that triggers the repair mechanism. The transfer occurs from the flavin photolyase cofactor to the cyclobutane ring of DNA, previously formed by light-induced cycloaddition of adjacent pyrimidine bases. The electron wave function dynamics accurately accounts for the previously proposed mechanism of transfer via the terminal methyl group of the flavin moiety present in the catalytic electron-donor cofactor, FADH(-), which also contains adenine. This latter moiety, which has often been assumed to be present mainly for structural reasons, instantaneously modifies the interaction between acceptor and donor by a variation of the electrostatic interactions so that the presence of its local atomic charges is necessary to trigger the transfer. In principle, knowledge of the details of the electron transfer dynamics and of the important role of polarization effects can be exploited to improve the efficiency of the repair mechanism in artificial systems.

  8. Adenine adlayers on Cu(111): XPS and NEXAFS study

    Energy Technology Data Exchange (ETDEWEB)

    Tsud, Nataliya; Bercha, Sofiia; Ševčíková, Klára; Matolín, Vladimír [Department of Surface and Plasma Science, Faculty of Mathematics and Physics, Charles University in Prague, V Holešovičkách 2, 18000 Prague 8 (Czech Republic); Acres, Robert G. [Elettra-Sincrotrone Trieste S.C.p.A., Area Science Park, Strada Statale 14, km 163.5, 34149 Basovizza, Trieste (Italy); Prince, Kevin C. [Elettra-Sincrotrone Trieste S.C.p.A., Area Science Park, Strada Statale 14, km 163.5, 34149 Basovizza, Trieste (Italy); Istituto Officina dei Materiali, Consiglio Nazionale delle Ricerche, 34149 Basovizza, Trieste (Italy)

    2015-11-07

    The adsorption of adenine on Cu(111) was studied by photoelectron and near edge x-ray absorption fine structure spectroscopy. Disordered molecular films were deposited by means of physical vapor deposition on the substrate at room temperature. Adenine chemisorbs on the Cu(111) surface with strong rehybridization of the molecular orbitals and the Cu 3d states. Annealing at 150 °C caused the desorption of weakly bonded molecules accompanied by formation of a short-range ordered molecular adlayer. The interface is characterized by the formation of new states in the valence band at 1.5, 7, and 9 eV. The present work complements and refines existing knowledge of adenine interaction with this surface. The coverage is not the main parameter that defines the adenine geometry and adsorption properties on Cu(111). Excess thermal energy can further rearrange the molecular adlayer and, independent of the initial coverage, the flat lying stable molecular adlayer is formed.

  9. The sonolysis and radiolysis of adenine and related biomolecules

    International Nuclear Information System (INIS)

    The sonolysis of adenine, its nucleoside adenosine and the carbohydrates glucose, fructose and ribose were investigated at 459 Hz. The insonation of air-saturated aqueous adenine solutions degrades adenine at a rate that is linear with time and independent of the initial concentration. The radiolytic decomposition of air-saturated aqueous adenine solutions were also investigated and the degradation products found to be essentially identical to those obtained by sonolysis. since the products derived from sonolysis and radiolysis were similar, a degradation mechanism can be proposed that accounts for all the observed products. The major feature of this mechanism is that the principal loci of attack are the C(8) position and the central C(4)-C(5) double bond. The sonolysis of air-saturated aqueous solutions of the carbohydrates results in the formation of products analogous to those produced by ionizing radiation. While two types of products are formed in the radiolysis of carbohydrate solutions, depending on the initial presence or absence of oxygen, the sonolysis of air-saturated carbohydrate solutions leads to the formation of both types of products. This is due to the depletion of oxygen from the solution during insonation. Existing mechanisms for the radiolytic decomposition of carbohydrates in the presence and absence of oxygen can be modified to rationalize the sonolysis products. Insonation of an aqueous solution of adenosine resulted in the production of adenine and ribose. The other products are consistent with those obtained in the ultrasonic degradation of adenine and ribose

  10. DNA adenine hypomethylation leads to metabolic rewiring in Deinococcus radiodurans.

    Science.gov (United States)

    Shaiwale, Nayana S; Basu, Bhakti; Deobagkar, Deepti D; Deobagkar, Dileep N; Apte, Shree K

    2015-08-01

    The protein encoded by DR_0643 gene from Deinococcus radiodurans was shown to be an active N-6 adenine-specific DNA methyltransferase (Dam). Deletion of corresponding protein reduced adenine methylation in the genome by 60% and resulted in slow-growth phenotype. Proteomic changes induced by DNA adenine hypomethylation were mapped by two-dimensional protein electrophoresis coupled with mass spectrometry. As compared to wild type D. radiodurans cells, at least 54 proteins were differentially expressed in Δdam mutant. Among these, 39 metabolic enzymes were differentially expressed in Δdam mutant. The most prominent change was DNA adenine hypomethylation induced de-repression of pyruvate dehydrogenase complex, E1 component (aceE) gene resulting in 10 fold increase in the abundance of corresponding protein. The observed differential expression profile of metabolic enzymes included increased abundance of enzymes involved in fatty acid and amino acid degradation to replenish acetyl Co-A and TCA cycle intermediates and diversion of phosphoenolpyruvate and pyruvate into amino acid biosynthesis, a metabolic rewiring attempt by Δdam mutant to restore energy generation via glycolysis-TCA cycle axis. This is the first report of DNA adenine hypomethylation mediated rewiring of metabolic pathways in prokaryotes.

  11. Excited-State Deactivation of Adenine by Electron-Driven Proton-Transfer Reactions in Adenine-Water Clusters: A Computational Study.

    Science.gov (United States)

    Wu, Xiuxiu; Karsili, Tolga N V; Domcke, Wolfgang

    2016-05-01

    The reactivity of photoexcited 9H-adenine with hydrogen-bonded water molecules in the 9H-adenine-(H2 O)5 cluster is investigated by using ab initio electronic structure methods, focusing on the photoreactivity of the three basic sites of 9H-adenine. The energy profiles of excited-state reaction paths for electron/proton transfer from water to adenine are computed. For two of the three sites, a barrierless or nearly barrierless reaction path towards a low-lying S1 -S0 conical intersection is found. This reaction mechanism, which is specific for adenine in an aqueous environment, can explain the substantially shortened excited-state lifetime of 9H-adenine in water. Depending on the branching ratio of the nonadiabatic dynamics at the S1 -S0 conical intersection, the electron/proton transfer process can enhance the photostability of 9H-adenine in water or can lead to the generation of adenine-H(⋅) and OH(⋅) free radicals. Although the branching ratio is yet unknown, these findings indicate that adenine might have served as a catalyst for energy harvesting by water splitting in the early stages of the evolution of life. PMID:26833826

  12. The family of N9-adenine: New entry for adenine-benzamide conjugates linked via versatile spacers

    Indian Academy of Sciences (India)

    Prabhpreet Singh

    2014-01-01

    We have prepared 4-nitrobenzamide-adenine conjugates (8, 13 and 14) linked with versatile spacer such as triethylene glycol (TEG), aminocaproic acid and ethyl chains which were eventually reduced to obtain the corresponding 4-aminobenzamide-adenine conjugates (1-3) in good yields. These conjugates bear a nucleobase for DNA recognition or self-assembly through base-pair complementarity, a biocompatible linker for interfacing with biological system, and a p-aminobenzamide moiety for pharmacological applications. The use of hydrophilic or lipophilic linkers may tune the dispersibility of these conjugates in different solvents, as well as impart different properties. In the preliminary experiments the versatility and application of these linkers has been tested for functionalization of SWCNTs.

  13. Influence of hydrogen bonding on the geometry of the adenine fragment

    Science.gov (United States)

    Słowikowska, Joanna Maria; Woźniak, Krzysztof

    1996-01-01

    The crystal structures of two adenine derivatives, N(6),9-dimethyl-8-butyladenine (I) and its hydrate (1 : 1) (II), have been determined by single-crystal X-ray diffraction. The geometrical features of both structures are discussed. The influence of protonation, substitution and hydrogen bond formation on the geometry of the adenine fragment was studied, based on data retrieved from the Cambridge Structural Database. Total correlation analysis showed mutual correlation between the structural parameters in the adenine ring system; partial correlation calculations for the adenine nucleoside fragments suggest intercorrelation between the parameters of the hydrogen bonding involved in base pairing and the N(adenine)-C(sugar) bond through the adenine fragment; few such correlations were found for fragments without the sugar substituent.

  14. Examination of tyrosine/adenine stacking interactions in protein complexes.

    Science.gov (United States)

    Copeland, Kari L; Pellock, Samuel J; Cox, James R; Cafiero, Mauricio L; Tschumper, Gregory S

    2013-11-14

    The π-stacking interactions between tyrosine amino acid side chains and adenine-bearing ligands are examined. Crystalline protein structures from the protein data bank (PDB) exhibiting face-to-face tyrosine/adenine arrangements were used to construct 20 unique 4-methylphenol/N9-methyladenine (p-cresol/9MeA) model systems. Full geometry optimization of the 20 crystal structures with the M06-2X density functional theory method identified 11 unique low-energy conformations. CCSD(T) complete basis set (CBS) limit interaction energies were estimated for all of the structures to determine the magnitude of the interaction between the two ring systems. CCSD(T) computations with double-ζ basis sets (e.g., 6-31G*(0.25) and aug-cc-pVDZ) indicate that the MP2 method overbinds by as much as 3.07 kcal mol(-1) for the crystal structures and 3.90 kcal mol(-1) for the optimized structures. In the 20 crystal structures, the estimated CCSD(T) CBS limit interaction energy ranges from -4.00 to -6.83 kcal mol(-1), with an average interaction energy of -5.47 kcal mol(-1), values remarkably similar to the corresponding data for phenylalanine/adenine stacking interactions. Geometry optimization significantly increases the interaction energies of the p-cresol/9MeA model systems. The average estimated CCSD(T) CBS limit interaction energy of the 11 optimized structures is 3.23 kcal mol(-1) larger than that for the 20 crystal structures.

  15. Adenine nucleotides as allosteric effectors of pea seed glutamine synthetase.

    Science.gov (United States)

    Knight, T J; Langston-Unkefer, P J

    1988-08-15

    The effects of adenine nucleotides on pea seed glutamine synthetase (EC 6.3.1.2) activity were examined as a part of our investigation of the regulation of this octameric plant enzyme. Saturation curves for glutamine synthetase activity versus ATP with ADP as the changing fixed inhibitor were not hyperbolic; greater apparent Vmax values were observed in the presence of added ADP than the Vmax observed in the absence of ADP. Hill plots of data with ADP present curved upward and crossed the plot with no added ADP. The stoichiometry of adenine nucleotide binding to glutamine synthetase was examined. Two molecules of [gamma-32P]ATP were bound per subunit in the presence of methionine sulfoximine. These ATP molecules were bound at an allosteric site and at the active site. One molecule of either [gamma-32P]ATP or [14C]ADP bound per subunit in the absence of methionine sulfoximine; this nucleotide was bound at an allosteric site. ADP and ATP compete for binding at the allosteric site, although ADP was preferred. ADP binding to the allosteric site proceeded in two kinetic phases. A Vmax value of 1.55 units/mg was measured for glutamine synthetase with one ADP tightly bound per enzyme subunit; a Vmax value of 0.8 unit/mg was measured for enzyme with no adenine nucleotide bound at the allosteric site. The enzyme activation caused by the binding of ADP to the allosteric sites was preceded by a lag phase, the length of which was dependent on the ADP concentration. Enzyme incubated in 10 mM ADP bound approximately 4 mol of ADP/mol of native enzyme before activation was observed; the activation was complete when 7-8 mol of ADP were bound per mol of the octameric, native enzyme. The Km for ATP (2 mM) was not changed by ADP binding to the allosteric sites. ADP was a simple competitive inhibitor (Ki = 0.05 mM) of ATP for glutamine synthetase with eight molecules of ADP tightly bound to the allosteric sites of the octamer. Binding of ATP to the allosteric sites led to marked

  16. Absorption spectroscopy of adenine, 9-methyladenine, and 2-aminopurine in helium nanodroplets

    NARCIS (Netherlands)

    S. Smolarek; A.M. Rijs; W.J. Buma; M. Drabbels

    2010-01-01

    High-resolution absorption spectra of adenine, 9-methyladenine and 2-aminopurine in helium nanodroplets have been recorded. In contrast to molecular beam experiments, large variations in linewidths are observed for adenine and 9-methyladenine. At the same time, the spectrum of 2-aminopurine remains

  17. File list: Oth.Emb.50.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Emb.50.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Embryo http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Emb.50.Adenine_N6-methylation.AllCell.bed ...

  18. File list: Oth.ALL.20.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.ALL.20.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n All cell types http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.ALL.20.Adenine_N6-methylation.AllCell.bed ...

  19. File list: Oth.Lar.20.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Lar.20.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Larvae http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Lar.20.Adenine_N6-methylation.AllCell.bed ...

  20. File list: Oth.ALL.10.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.ALL.10.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n All cell types http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.ALL.10.Adenine_N6-methylation.AllCell.bed ...

  1. File list: Oth.Emb.10.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Emb.10.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Embryo http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Emb.10.Adenine_N6-methylation.AllCell.bed ...

  2. File list: Oth.Unc.50.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Unc.50.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Unclassified http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Unc.50.Adenine_N6-methylation.AllCell.bed ...

  3. File list: Oth.Unc.20.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Unc.20.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Unclassified http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Unc.20.Adenine_N6-methylation.AllCell.bed ...

  4. File list: Oth.Unc.10.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Unc.10.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Unclassified http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Unc.10.Adenine_N6-methylation.AllCell.bed ...

  5. File list: Oth.Lar.05.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Lar.05.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Larvae http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Lar.05.Adenine_N6-methylation.AllCell.bed ...

  6. File list: Oth.Lar.10.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Lar.10.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Larvae http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Lar.10.Adenine_N6-methylation.AllCell.bed ...

  7. File list: Oth.Emb.20.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Emb.20.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Embryo http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Emb.20.Adenine_N6-methylation.AllCell.bed ...

  8. File list: Oth.Adl.05.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Adl.05.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Adult http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Adl.05.Adenine_N6-methylation.AllCell.bed ...

  9. File list: Oth.Lar.50.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Lar.50.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Larvae http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Lar.50.Adenine_N6-methylation.AllCell.bed ...

  10. File list: Oth.ALL.50.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.ALL.50.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n All cell types http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.ALL.50.Adenine_N6-methylation.AllCell.bed ...

  11. File list: Oth.Adl.20.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Adl.20.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Adult http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Adl.20.Adenine_N6-methylation.AllCell.bed ...

  12. File list: Oth.Adl.10.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Adl.10.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Adult http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Adl.10.Adenine_N6-methylation.AllCell.bed ...

  13. File list: Oth.Unc.05.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Unc.05.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Unclassified http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Unc.05.Adenine_N6-methylation.AllCell.bed ...

  14. File list: Oth.Emb.05.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Emb.05.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Embryo http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Emb.05.Adenine_N6-methylation.AllCell.bed ...

  15. File list: Oth.Adl.50.Adenine_N6-methylation.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Adl.50.Adenine_N6-methylation.AllCell ce10 TFs and others Adenine N6-methylatio...n Adult http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Adl.50.Adenine_N6-methylation.AllCell.bed ...

  16. Renoprotective effect of the xanthine oxidoreductase inhibitor topiroxostat on adenine-induced renal injury.

    Science.gov (United States)

    Kamijo-Ikemori, Atsuko; Sugaya, Takeshi; Hibi, Chihiro; Nakamura, Takashi; Murase, Takayo; Oikawa, Tsuyoshi; Hoshino, Seiko; Hisamichi, Mikako; Hirata, Kazuaki; Kimura, Kenjiro; Shibagaki, Yugo

    2016-06-01

    The aim of the present study was to reveal the effect of a xanthine oxidoreductase (XOR) inhibitor, topiroxostat (Top), compared with another inhibitor, febuxostat (Feb), in an adenine-induced renal injury model. We used human liver-type fatty acid-binding protein (L-FABP) chromosomal transgenic mice, and urinary L-FABP, a biomarker of tubulointerstitial damage, was used to evaluate tubulointerstitial damage. Male transgenic mice (n = 24) were fed a 0.2% (wt/wt) adenine-containing diet. Two weeks after the start of this diet, renal dysfunction was confirmed, and the mice were divided into the following four groups: the adenine group was given only the diet containing adenine, and the Feb, high-dose Top (Top-H), and low-dose Top (Top-L) groups were given diets containing Feb (3 mg/kg), Top-H (3 mg/kg), and Top-L (1 mg/kg) in addition to adenine for another 2 wk. After withdrawal of the adenine diet, each medication was continued for 2 wk. Serum creatinine levels, the degree of macrophage infiltration, tubulointerstitial damage, renal fibrosis, urinary 15-F2t-isoprostane levels, and renal XOR activity were significantly attenuated in the kidneys of the Feb, Top-L, and Top-H groups compared with the adenine group. Serum creatinine levels in the Top-L and Top-H groups as well as renal XOR in the Top-H group were significantly lower than those in the Feb group. Urinary excretion of L-FABP in both the Top-H and Top-L groups was significantly lower than in the adenine and Feb groups. In conclusion, Top attenuated renal damage in an adenine-induced renal injury model. PMID:27029427

  17. Renoprotective effect of the xanthine oxidoreductase inhibitor topiroxostat on adenine-induced renal injury.

    Science.gov (United States)

    Kamijo-Ikemori, Atsuko; Sugaya, Takeshi; Hibi, Chihiro; Nakamura, Takashi; Murase, Takayo; Oikawa, Tsuyoshi; Hoshino, Seiko; Hisamichi, Mikako; Hirata, Kazuaki; Kimura, Kenjiro; Shibagaki, Yugo

    2016-06-01

    The aim of the present study was to reveal the effect of a xanthine oxidoreductase (XOR) inhibitor, topiroxostat (Top), compared with another inhibitor, febuxostat (Feb), in an adenine-induced renal injury model. We used human liver-type fatty acid-binding protein (L-FABP) chromosomal transgenic mice, and urinary L-FABP, a biomarker of tubulointerstitial damage, was used to evaluate tubulointerstitial damage. Male transgenic mice (n = 24) were fed a 0.2% (wt/wt) adenine-containing diet. Two weeks after the start of this diet, renal dysfunction was confirmed, and the mice were divided into the following four groups: the adenine group was given only the diet containing adenine, and the Feb, high-dose Top (Top-H), and low-dose Top (Top-L) groups were given diets containing Feb (3 mg/kg), Top-H (3 mg/kg), and Top-L (1 mg/kg) in addition to adenine for another 2 wk. After withdrawal of the adenine diet, each medication was continued for 2 wk. Serum creatinine levels, the degree of macrophage infiltration, tubulointerstitial damage, renal fibrosis, urinary 15-F2t-isoprostane levels, and renal XOR activity were significantly attenuated in the kidneys of the Feb, Top-L, and Top-H groups compared with the adenine group. Serum creatinine levels in the Top-L and Top-H groups as well as renal XOR in the Top-H group were significantly lower than those in the Feb group. Urinary excretion of L-FABP in both the Top-H and Top-L groups was significantly lower than in the adenine and Feb groups. In conclusion, Top attenuated renal damage in an adenine-induced renal injury model.

  18. Adenine nucleotides as allosteric effectors of PEA seed glutamine synthetase

    Energy Technology Data Exchange (ETDEWEB)

    Unkefer, P.J.; Knight, T.J.

    1986-05-01

    The energy charge in the plant cell has been proposed as a regulator of glutamine synthetase (GS) activity. The authors have shown that 2.1 moles of ..gamma..(/sup 32/P)-ATP were bound/mole subunits of purified pea seed GS during complete inactivation with methionine sulfoximine. Since GS has one active site per subunit, the second binding site provides the potential for allosteric regulation of GS by adenine nucleotides. The authors have investigated the inhibition of the ATP-dependent synthetic activity by ADP and AMP. ADP and AMP cannot completely inhibit GS; but ATP does overcome the inhibition by ADP and AMP as shown by plots of % inhibition vs inhibitor concentration. This indicates that inhibition of GS by ADP or AMP is not completely due to competitive inhibition. In the absence of ADP or AMP, double reciprocal plots for ATP are linear below 10 mM; however, in the presence of either ADP or AMP these pots are curvilinear downwards. The ratio of Vm/asymptote is less than 1. The Hill number for ATP in the absence of ADP or AMP is 0.93 but decreases with increasing ADP or AMP to a value of 0.28 with 10 mM ADP. These data are consistent with negative cooperativity by ADP and AMP. Thus, as the ADP/ATP or AMP/ATP ratios are increased GS activity decreases. This is consistent with regulation of GS activity by energy charge in planta.

  19. Effects of hypobaric hypoxia on adenine nucleotide pools, adenine nucleotide transporter activity and protein expression in rat liver

    Institute of Scientific and Technical Information of China (English)

    Cong-Yang Li; Jun-Ze Liu; Li-Ping Wu; Bing Li; Li-Fen Chen

    2006-01-01

    AIM: To explore the effect of hypobaric hypoxia on mitochondrial energy metabolism in rat liver.METHODS: Adult male Wistar rats were exposed to a hypobaric chamber simulating 5000 m high altitude for 23 h every day for 0 (HO), 1 (H1), 5 (HS), 15 (H15) and 30 d (H30) respectively. Rats were sacrificed by decapitation and liver was removed. Liver mitochondria were isolated by differential centrifugation program. The size of adenine nucleotide pool (ATP, ADP, and AMP) in tissue and mitochondria was separated and measured by high performance liquid chromatography (HPLC). The adenine nucleotide transporter (ANT) activity was determined by isotopic technique. The ANT total protein level was determined by Western blot. RESULTS: Compared with HO group, intra-mitochondrial ATP content decreased in all hypoxia groups. However,the H5 group reached the lowest point (70.6%) (P< 0.01)when compared to the control group. Intra-mitochondrial ADP and AMP level showed similar change in all hypoxia groups and were significantly lower than that in HO group. In addition, extra-mitochondrial ATP and ADP content decreased significantly in all hypoxia groups.Furthermore, extra-mitochondrial AMP in groups H5, H15and H30 was significantly lower than that in HO group,whereas H1 group had no marked change compared to the control situation. The activity of ANT in hypoxia groups decreased significantly, which was the lowest in H5 group (55.7%) (P<0.01) when compared to HO group. ANT activity in H30 group was higher than in H15 group, but still lower than that in HO group. ANT protein level in H5, H15, H30 groups, compared with HO group decreased significantly, which in H5 group was the lowest, being 27.1% of that in HO group (P<0.01). ANT protein level in H30 group was higher than in H15 group,but still lower than in HO group.CONCLUSION: Hypobaric hypoxia decreases the mitochondrial ATP content in rat liver, while mitochondrial ATP level recovers during long-term hypoxia exposure.The lower

  20. Improved Growth and Stress Tolerance in the Arabidopsis oxt1 Mutant Triggered by Altered Adenine Metabolism

    Institute of Scientific and Technical Information of China (English)

    Suchada Sukrong; Kil-Young Yun; Patrizia Stadler; Charan Kumar; Tony Facciuolo; Barbara A.Moffatt; Deane L.Falcone

    2012-01-01

    Plants perceive and respond to environmental stresses with complex mechanisms that are often associated with the activation of antioxidant defenses.A genetic screen aimed at isolating oxidative stress-tolerant lines of Arabidopsis thaliana has identified oxt1,a line that exhibits improved tolerance to oxidative stress and elevated temperature but displays no apparent deleterious growth effects under non-stress conditions.Oxt1 harbors a mutation that arises from the altered expression of a gene encoding adenine phosphoribosyltransferase (APT1),an enzyme that converts adenine to adenosine monophosphate (AMP),indicating a link between purine metabolism,whole-plant growth responses,and stress acclimation.The oxt1 mutation results in decreased APT1 expression that leads to reduced enzymatic activity.Correspondingly,oxt1 plants possess elevated levels of adenine.Decreased APT enzyme activity directly correlates with stress resistance in transgenic lines that ectopically express APT1.The metabolic alteration in oxt1 plants also alters the expression of several antioxidant defense genes and the response of these genes to oxidative challenge.Finally,it is shown that manipulation of adenine levels can induce stress tolerance to wild-type plants.Collectively,these results show that alterations in cellular adenine levels can trigger stress tolerance and improve growth,leading to increases in plant biomass.The results also suggest that adenine might play a part in the signals that modulate responses to abiotic stress and plant growth.

  1. Benchmark Thermochemistry for Biologically Relevant Adenine and Cytosine. A Combined Experimental and Theoretical Study.

    Science.gov (United States)

    Emel'yanenko, Vladimir N; Zaitsau, Dzmitry H; Shoifet, Evgeni; Meurer, Florian; Verevkin, Sergey P; Schick, Christoph; Held, Christoph

    2015-09-17

    The thermochemical properties available in the literature for adenine and cytosine are in disarray. A new condensed phase standard (p° = 0.1 MPa) molar enthalpy of formation at T = 298.15 K was measured by using combustion calorimetry. New molar enthalpies of sublimation were derived from the temperature dependence of vapor pressure measured by transpiration and by the quarz-crystal microbalance technique. The heat capacities of crystalline adenine and cytosine were measured by temperature-modulated DSC. Thermodynamic data on adenine and cytosine available in the literature were collected, evaluated, and combined with our experimental results. Thus, the evaluated collection of data together with the new experimental results reported here has helped to resolve contradictions in the available enthalpies of formation. A set of reliable thermochemical data is recommended for adenine and cytosine for further thermochemical calculations. Quantum-chemical calculations of the gas phase molar enthalpies of formation of adenine and cytosine have been performed by using the G4 method and results were in excellent agreement with the recommended experimental data. The standard molar entropies of formation and the standard molar Gibbs functions of formation in crystal and gas state have been calculated. Experimental vapor-pressure data measured in this work were used to estimate pure-component PC-SAFT parameters. This allowed modeling solubility of adenine and cytosine in water over the temperature interval 278-310 K.

  2. OTOTOXIC MODEL OF OXALIPLATIN AND PROTECTION FROM NICOTINAMIDE ADENINE DINUCLEOTIDE

    Institute of Scientific and Technical Information of China (English)

    DING Dalian; JIANG Haiyan; FU Yong; LI Yongqi; Richard Salvi; Shinichi Someya; Masaru Tanokura

    2013-01-01

    Oxaliplatin, an anticancer drug commonly used to treat colorectal cancer and other tumors, has a number of serious side effects, most notably neuropathy and ototoxicity. To gain insights into its ototoxic profile, oxaliplatin was applied to rat cochlear organ cultures. Consistent with it neurotoxic propensity, oxaliplatin selectively damaged nerve fibers at a very low dose 1 µM. In contrast, the dose required to damage hair cells and spiral ganglion neurons was 50 fold higher (50 µM). Oxailiplatin-induced cochlear lesions initial-ly increased with dose, but unexpectedly decreased at very high doses. This non-linear dose response could be related to depressed oxaliplatin uptake via active transport mechanisms. Previous studies have demon-strated that axonal degeneration involves biologically active processes which can be greatly attenuated by nicotinamide adenine dinucleotide (NAD+). To determine if NAD+would protect spiral ganglion axons and the hair cells from oxaliplatin damage, cochlear cultures were treated with oxaliplatin alone at doses of 10 µM or 50 µM respectively as controls or combined with 20 mM NAD+. Treatment with 10 µM oxaliplatin for 48 hours resulted in minor damage to auditory nerve fibers, but spared cochlear hair cells. However, when cochlear cultures were treated with 10 µM oxaliplatin plus 20 mM NAD+, most auditory nerve fibers were intact. 50 µM oxaliplatin destroyed most of spiral ganglion neurons and cochlear hair cells with apop-totic characteristics of cell fragmentations. However, 50 µM oxaliplatin plus 20 mM NAD+treatment great-ly reduced neuronal degenerations and hair cell missing. The results suggested that NAD+provides signifi-cant protection against oxaliplatin-induced neurotoxicity and ototoxicity, which may be due to its actions of antioxidant, antiapoptosis, and energy supply.

  3. Sequence-dependent folding landscapes of adenine riboswitch aptamers

    Science.gov (United States)

    Lin, Jong-Chin; Hyeon, Changbong; Thirumalai, D.

    Prediction of the functions of riboswitches requires a quantitative description of the folding landscape so that the barriers and time scales for the conformational change in the switching region in the aptamer can be estimated. Using a combination of all atom molecular dynamics and coarse-grained model simulations we studied the response of adenine (A) binding add and pbuE A-riboswitches to mechanical force. The two riboswitches contain a structurally similar three-way junction formed by three paired helices, P1, P2, and P3, but carry out different functions. Using pulling simulations, with structures generated in MD simulations, we show that after P1 rips the dominant unfolding pathway in add A-riboswitch is the rupture of P2 followed by unraveling of P3. In the pbuE A-riboswitch, after P1 unfolds P3 ruptures ahead of P2. The order of unfolding of the helices, which is in accord with single molecule pulling experiments, is determined by the relative stabilities of the individual helices. Our results show that the stability of isolated helices determines the order of assembly and response to force in these non-coding regions. We use the simulated free energy profile for pbuE A-riboswitch to estimate the time scale for allosteric switching, which shows that this riboswitch is under kinetic control lending additional support to the conclusion based on single molecule pulling experiments. A consequence of the stability hypothesis is that a single point mutation (U28C) in the P2 helix of the add A-riboswitch, which increases the stability of P2, would make the folding landscapes of the two riboswitches similar. This prediction can be tested in single molecule pulling experiments.

  4. Determination of adenine based on the fluorescence recovery of the L-Tryptophan-Cu2+ complex

    Science.gov (United States)

    Duan, Ruilin; Li, Chunyan; Liu, Shaopu; Liu, Zhongfang; Li, Yuanfang; Yuan, Yusheng; Hu, Xiaoli

    2016-01-01

    A simple and sensitive method for determination of adenine was developed based on fluorescence quenching and recovery of L-Tryptophan (L-Trp). The fluorescence of L-Trp could efficiently quenched by copper ion compared with other common metal ions. Upon addition of adenine (Ade) in L-Trp-Cu(II) system, the fluorescence was reoccurred. Under the optimum conditions, the recovery fluorescence intensity was linearly correlated with the concentration of adenine in the range from 0.34 to 25.0 μmol L-1, with a correlation coefficient (R2) of 0.9994. The detection limit (3σ/k) was 0.046 μmol L-1, indicating that this method could applied to detect trace adenine. In this study, amino acids including L-Trp, D-Trp, L-Tyr, D-Tyr, L-Phe, D-Phe were investigated and only L-Trp could well chelated copper ion. Additionally, the mechanism of quench and recovery also were discussed and the method was successfully applied to detect the adenine in DNA with satisfactory results.

  5. A computational study of adenine, uracil, and cytosine adsorption upon AlN and BN nano-cages

    International Nuclear Information System (INIS)

    Density-functional theory calculations are used to investigate the interaction of Al12N12 and B12N12 clusters with the adenine (A), uracil (U), and cytosine (C) molecules. The current calculations demonstrate that these hybrid adsorbent materials are able to adsorb the adenine, uracil, and cytosine molecules through exothermic processes. Our theoretical results reveal improvement in the adsorption of adenine, uracil, and cytosine on Al12N12 and B12N12. It is observed that B12N12 is highly sensitive to adenine, uracil, and cytosine compared with Al12N12 to serve as a biochemical sensor.

  6. Excited-state lifetime of adenine near the first electronic band origin.

    Science.gov (United States)

    Kang, Hyuk; Chang, Jinyoung; Lee, Sang Hak; Ahn, Tae Kyu; Kim, Nam Joon; Kim, Seong Keun

    2010-10-21

    The excited-state lifetime of supersonically cooled adenine was measured in the gas phase by femtosecond pump-probe transient ionization as a function of excitation energy between 36 100 and 37 500cm(-1). The excited-state lifetime of adenine is ∼2ps around the 0-0 band of the (1)L(b) ππ(∗) state (36 105cm(-1)). The lifetime drops to ∼1ps when adenine is excited to the (1)L(a) ππ(∗) state with the pump energy at 36 800cm(-1) and above. The excited-state lifetimes of (1)L(a) and (1)L(b) ππ(∗) states are differentiated in accordance with previous frequency-resolved and computational studies.

  7. Cleavage of nicotinamide adenine dinucleotide by the ribosome-inactivating protein from Momordica charantia.

    Science.gov (United States)

    Vinkovic, M; Dunn, G; Wood, G E; Husain, J; Wood, S P; Gill, R

    2015-09-01

    The interaction of momordin, a type 1 ribosome-inactivating protein from Momordica charantia, with NADP(+) and NADPH has been investigated by X-ray diffraction analysis of complexes generated by co-crystallization and crystal soaking. It is known that the proteins of this family readily cleave the adenine-ribose bond of adenosine and related nucleotides in the crystal, leaving the product, adenine, bound to the enzyme active site. Surprisingly, the nicotinamide-ribose bond of oxidized NADP(+) is cleaved, leaving nicotinamide bound in the active site in the same position but in a slightly different orientation to that of the five-membered ring of adenine. No binding or cleavage of NADPH was observed at pH 7.4 in these experiments. These observations are in accord with current views of the enzyme mechanism and may contribute to ongoing searches for effective inhibitors. PMID:26323301

  8. Comparative study of spontaneous deamination of adenine and cytosine in unbuffered aqueous solution at room temperature

    Science.gov (United States)

    Wang, Shiliang; Hu, Anguang

    2016-06-01

    Adenine in unbuffered nanopure water at a concentration of 2 mM is completely deaminated (>99%) to hypoxanthine at room temperature in ca. 10 weeks, with an estimated half-life (t1/2) less than 10 days, about six orders of magnitude faster than previously reported. Cytosine is not deaminated under the same condition, even after 3 years. This is in contrast to previous observations that cytosine deaminates 20-40 times faster than adenine free base, in nucleoside, in nucleotide and in single-stranded DNA in buffered neutral aqueous solutions.

  9. Modification of flavin adenine dinucleotide in alcohol oxidase of the yeast Hansenula polymorpha

    NARCIS (Netherlands)

    Bystrykh, Leonid V.; Dijkhuizen, Lubbert; Harder, Willem

    1991-01-01

    Alcohol oxidase, a major peroxisomal protein of methanol-utilizing yeasts, may possess two different forms of flavin adenine dinucleotide, classical FAD and so-called modified FAD (mFAD). Conversion of FAD into mFAD was observed both in purified preparations of the enzyme and in cells grown in batch

  10. The effect of caffeine and adenine on radiation induced suppression of DNA synthesis, and cell survival

    International Nuclear Information System (INIS)

    Exposure of cultured mammalian cells to ionizing radiation or UV light results in a transient decrease in the rate of DNA synthesis. This depression in synthetic rate may be attenuated or deferred via a post-irradiation treatment with caffeine or adenine. It has been suggested that this attenuation may increase the fixation of damage and, therefore, increase radiation sensitivity. However, it has been previously reported that, for V79 cells treated with caffeine or adenine, no correlation exists between the extent of depression and cell survival. The present investigation expands upon these findings by examining the effect of caffeine or adenine post-irradiation treatment on two cell lines with normal UV sensitivity, mouse 3T3 and CHO AA8 cells, and one UV sensitive cell line, CHO UV5 cells. Both caffeine and adenine have been found to reduce, or delay, the suppression in DNA synthesis in all three cell lines. Surprisingly, caffeine appeared to induced even the UV5 cells to recover DNA synthetic ability. The amount of reduction in suppression of DNA synthesis, however, varies between the different cell lines and no consistent relationship with cell survival has emerged

  11. Effect of AST-120 on Endothelial Dysfunction in Adenine-Induced Uremic Rats

    Directory of Open Access Journals (Sweden)

    Yuko Inami

    2014-01-01

    Full Text Available Aim. Chronic kidney disease (CKD represents endothelial dysfunction. Monocyte adhesion is recognized as the initial step of arteriosclerosis. Indoxyl sulfate (IS is considered to be a risk factor for arteriosclerosis in CKD. Oral adsorbent AST-120 retards deterioration of renal function, reducing accumulation of IS. In the present study, we determined the monocyte adhesion in the adenine-induced uremic rats in vivo and effects of AST-120 on the adhesion molecules. Methods. Twenty-four rats were divided into control, control+AST-120, adenine, and adenine+AST-120 groups. The number of monocytes adherent to the endothelium of thoracic aorta by imaging the entire endothelial surface and the mRNA expressions of adhesion and atherosclerosis-related molecules were examined on day 49. The mRNA expressions of ICAM-1 and VCAM-1 in human umbilical vein endothelial cells were also examined. Results. Adenine increased the number of adherent monocytes, and AST-120 suppressed the increase. The monocyte adhesion was related to serum creatinine and IS in sera. Overexpression of VCAM-1 and TGF-β1 mRNA in the arterial walls was observed in uremic rats. IS induced increase of the ICAM-1 and VCAM-1 mRNA expressions in vitro. Conclusion. It appears that uremic condition introduces the monocyte adhesion to arterial wall and AST-120 might inhibit increasing of the monocyte adherence with CKD progression.

  12. SERS, XPS, and DFT Study of Adenine Adsorption on Silver and Gold Surfaces.

    Science.gov (United States)

    Pagliai, Marco; Caporali, Stefano; Muniz-Miranda, Maurizio; Pratesi, Giovanni; Schettino, Vincenzo

    2012-01-19

    The adsorption of adenine on silver and gold surfaces has been investigated combining density functional theory calculations with surface-enhanced Raman scattering and angle-resolved X-ray photoelectron spectroscopy measurements, obtaining useful insight into the orientation and interaction of the nucleobase with the metal surfaces.

  13. Kinetic analysis of Yersinia pestis DNA adenine methyltransferase activity using a hemimethylated molecular break light oligonucleotide.

    Directory of Open Access Journals (Sweden)

    Robert J Wood

    Full Text Available BACKGROUND: DNA adenine methylation plays an important role in several critical bacterial processes including mismatch repair, the timing of DNA replication and the transcriptional control of gene expression. The dependence of bacterial virulence on DNA adenine methyltransferase (Dam has led to the proposal that selective Dam inhibitors might function as broad spectrum antibiotics. METHODOLOGY/PRINCIPAL FINDINGS: Herein we report the expression and purification of Yersinia pestis Dam and the development of a continuous fluorescence based assay for DNA adenine methyltransferase activity that is suitable for determining the kinetic parameters of the enzyme and for high throughput screening against potential Dam inhibitors. The assay utilised a hemimethylated break light oligonucleotide substrate containing a GATC methylation site. When this substrate was fully methylated by Dam, it became a substrate for the restriction enzyme DpnI, resulting in separation of fluorophore (fluorescein and quencher (dabcyl and therefore an increase in fluorescence. The assays were monitored in real time using a fluorescence microplate reader in 96 well format and were used for the kinetic characterisation of Yersinia pestis Dam, its substrates and the known Dam inhibitor, S-adenosylhomocysteine. The assay has been validated for high throughput screening, giving a Z-factor of 0.71+/-0.07 indicating that it is a sensitive assay for the identification of inhibitors. CONCLUSIONS/SIGNIFICANCE: The assay is therefore suitable for high throughput screening for inhibitors of DNA adenine methyltransferases and the kinetic characterisation of the inhibition.

  14. Probing electronic coupling between adenine bases in RNA strands from synchrotron radiation circular dichroism experiments

    DEFF Research Database (Denmark)

    Nielsen, Lisbeth Munksgård; Hoffmann, Søren Vrønning; Nielsen, Steen Brøndsted

    2012-01-01

    Circular dichroism spectra (176–330 nm) of RNA adenine oligomers, (rA)n (n = 1–10, 12, 15, and 20), reveal electronic coupling between two bases in short strands. The number of interacting bases in long strands is more and larger than that reported previously for the corresponding DNA strands....

  15. ON THE INTERACTION OF ADENINE WITH IONIZING RADIATION: MECHANISTICAL STUDIES AND ASTROBIOLOGICAL IMPLICATIONS

    International Nuclear Information System (INIS)

    The molecular inventory available on the prebiotic Earth was likely derived from both terrestrial and extraterrestrial sources. A complete description of which extraterrestrial molecules may have seeded early Earth is therefore necessary to fully understand the prebiotic evolution which led to life. Galactic cosmic rays (GCRs) are expected to cause both the formation and destruction of important biomolecules-including nucleic acid bases such as adenine-in the interstellar medium within the ices condensed on interstellar grains. The interstellar ultraviolet (UV) component is expected to photochemically degrade gas-phase adenine on a short timescale of only several years. However, the destruction rate is expected to be significantly reduced when adenine is shielded in dense molecular clouds or even within the ices of interstellar grains. Here, biomolecule destruction by the energetic charged particle component of the GCR becomes important as it is not fully attenuated. Presented here are results on the destruction rate of the nucleobase adenine in the solid state at 10 K by energetic electrons, as generated in the track of cosmic ray particles as they penetrate ices. When both UV and energetic charged particle destructive processes are taken into account, the half-life of adenine within dense interstellar clouds is found to be ∼6 Myr, which is on the order of a star-forming molecular cloud. We also discuss chemical reaction pathways within the ices to explain the production of observed species, including the formation of nitriles (R-C≡N), epoxides (C-O-C), and carbonyl functions (R-C=O).

  16. Watson-Crick Base Pairing, Electronic and Photophysical Properties of Triazole Modified Adenine Analogues: A Computational Study

    KAUST Repository

    Das, Shubhajit

    2015-09-17

    We employ first-principles Density Functional Theory (DFT) and time-dependent DFT (TDDFT) to elucidate structural, electronic and optical properties of a few recently reported triazole adenine nucleobase analogues. The results are compared against the findings obtained for both natural adenine nucleobase and available experimental data. The optical absorption of these adenine analogues are calculated both in gas-phase and in solvent (methanol) using Polarized Continuum Model (PCM). We find that all the analogues show a red-shifted absorption profile as compared to adenine. Our simulated emission spectra in solvent compare fairly well with experimentally observed results. We investigate base paring ability of these adenine analogues with thymine. The calculations on the intrinsic stability of these base pairs ascertain that all the adenine analogues form the hydrogen bonded Watson-Crick base pair with similar H-bonding energy as obtained for natural adenine-thymine base pair. In our study, we provide a microscopic origin of the low-energy absorption and emission peaks, observed experimentally.

  17. Differences in Electrostatic Potential Around DNA Fragments Containing Adenine and 8-oxo-Adenine. An Analysis Based on Regular Cylindrical Projection

    Energy Technology Data Exchange (ETDEWEB)

    Haranczyk, Maciej; Miller, John H; Gutowski, Maciej S

    2007-07-01

    Changes of electrostatic potential (EP) around the DNA molecule resulting from chemical modifications of nucleotides may play a role in enzymatic recognition of damaged sites. Effects of chemical modifications of nucleotides on the structure of DNA have been characterized through large scale density functional theory computations. Quantum mechanical structural optimizations of DNA fragments with three pairs of nucleotides and accompanying counteractions were performed with a B3LYP exchange-correlation functional and 6-31G** basis sets. The “intact” DNA fragment contained adenine in the middle layer, while the “damaged” fragment had the adenine replaced with 8-oxo-adenine. The electrostatic potential around these DNA fragments was projected on a cylindrical surface around the double helix. The two-dimensional maps of EP of the intact and damaged DNA fragments were analyzed to identify these modifications of EP that result from the occurrence of 8-oxo-adenine (8oA). It was found that distortions of a phosphate group neighboring 8oA and displacements of the accompanying countercation are clearly reflected in the EP maps. Helpful discussions Michel Dupuis are gratefully acknowledged. Authors wish to thank Marcel Swart for directing us to a compilation of van der Waals radii. This work was supported by the: (i) US DOE Office of Biological and Environmental Research, Low Dose Radiation Research Program (M.G. and M.H.), (ii) the Office of Science (BER), U. S. Department of Energy, Grant No. DE-FG03-02ER63470 (JHM), (iii) Polish State Committee for Scientific Research (KBN) Grant DS/8221-4-0140-6 (MG), (iv) European Social Funds (EFS) ZPORR/2.22/II/2.6/ARP/U/2/05 (M.H.). M.H. holds the Foundation for Polish Science (FNP) award for young scientists. The calculations were performed at the Academic Computer Center in Gdansk (TASK) and at the Molecular Science Computing Facility (MSCF) in the William R. Wiley Environmental Molecular Sciences Laboratory, a national

  18. The influence of pH on the structure of adenine monolayers adsorbed at Au(110)/electrolyte interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Bowfield, A.; Smith, C.I.; Mansley, C.P.; Weightman, P. [Department of Physics, Oliver Lodge Laboratory, University of Liverpool, L69 7ZE (United Kingdom)

    2010-08-15

    The pH of the solution is shown to significantly effect the reflection anisotropy spectroscopy (RAS) profiles of adenine adsorbed at Au(110)/electrolyte interfaces. At pH 12.8 the net adsorption is very weak due the formation of negative adenine ions in solution. The sensitivity of the RAS profiles to the pH of the solution is probably due to a change in the geometry of the adsorbed molecules caused by a disruption of the base stacking configuration that is adopted when adenine is adsorbed from solutions at pH 7.1. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  19. Preparation of /sup 14/C-labelled AMP, ADP and ATP from adenine-8-/sup 14/C by using Brevibacterium ammoniagenes

    Energy Technology Data Exchange (ETDEWEB)

    Pande, V.N. (Bhabha Atomic Research Centre, Bombay (India). Biochemistry and Food Technology Div.)

    1985-04-01

    High radiochemical yields of /sup 14/C-labelled adenine nucleotides (AMP, 4.6%, ADP, 15.5% and ATP 59.5%) could be obtained by growing the cells of Brevibacterium ammoniagenes in the presence of /sup 14/C-adenine. The specific radioactivity of the adenine nucleotides almost reached that of /sup 14/C-adenine indicating negligible dilution of the label. The procedure is convenient and especially suited for commercial preparation of the radiolabelled nucleotides directly from labelled adenine. Preliminary results indicate that the organism could also be used for the preparation of radiolabelled guanine nucleotides.

  20. Induction of nucleoside phosphorylase in Enterobacter aerogenes and enzymatic synthesis of adenine arabinoside

    Institute of Scientific and Technical Information of China (English)

    Xiao-kun WEI; Qing-bao DING; Lu ZHANG; Yong-li GUO; Lin OU; Chang-lu WANG

    2008-01-01

    Nucleoside phosphorylases (NPases) were found to be induced in Enterobacter aerogenes DGO-04, and cytidine and cytidine 5'-monophosphate (CMP) were the best inducers. Five mmol/L to fifteen mmol/L cytidine or CMP could distinctly increase the activities of purine nucleoside phosphorylase (PNPase), uridine phosphorylase (UPase) and thymidine phosphorylase (TPase) when they were added into medium from 0 to 8 h. In the process of enzymatic synthesis of adenine arabinoside from adenine and uracil arabinoside with wet cells ofEnterobacter aerogenes DCJO-04 induced by cytidine or CMP, the reaction time could be shortened from 36 to 6 h. After enzymatic reaction the activity of NPase in the cells induced remained higher than that in the cells uninduced.

  1. Deviant Nicotinic Acid Adenine Dinucleotide Phosphate (NAADP)-mediated Ca2+ Signaling upon Lysosome Proliferation*

    OpenAIRE

    Dickinson, G. D.; Churchill, G. C.; Brailoiu, E; Patel, S.

    2010-01-01

    Accumulating evidence suggests that the endolysosomal system is a novel intracellular Ca2+ pool mobilized by the second messenger, nicotinic acid adenine dinucleotide phosphate (NAADP). Although lysosomes in neurons are known to proliferate in numerous neurodegenerative diseases and during the normal course of aging, little is known concerning the effect of lysosomal proliferation on Ca2+ homeostasis. Here, we induce proliferation of lysosomes in primary cultures of rat hippocampal neurons an...

  2. First prebiotic generation of a ribonucleotide from adenine, D-ribose and trimetaphosphate.

    Science.gov (United States)

    Baccolini, Graziano; Boga, Carla; Micheletti, Gabriele

    2011-03-28

    Adenosine monophosphate isomers are obtained by self-assembling of adenine, D-ribose and trimetaphosphate in aqueous solution in good yields. This generation of a ribonucleotide from its three molecular components occurs in a one-pot reaction at room temperature for about 30-40 days and with high chemio-, regio-, and stereo-selectivity. Similar results are obtained with guanine. A mechanism is also proposed. PMID:21305098

  3. Downregulation of adenine nucleotide translocator 1 exacerbates tumor necrosis factor-α-mediated cardiac inflammatory responses

    OpenAIRE

    Pan, Shi; Wang, Nadan; Bisetto, Sara; Yi, Bing; Sheu, Shey-Shing

    2014-01-01

    Inflammation contributes significantly to cardiac dysfunction. Although the initial phase of inflammation is essential for repair and healing, excessive proinflammatory cytokines are detrimental to the heart. We found that adenine nucleotide translocator isoform-1 (ANT1) protein levels were significantly decreased in the inflamed heart of C57BL/6 mice following cecal ligation and puncture. To understand the molecular mechanisms involved, we performed small-interfering RNA-mediated knockdown o...

  4. Insulin resistance and dysregulation of tryptophan – kynurenine and kynurenine – nicotinamide adenine dinucleotide metabolic pathways

    OpenAIRE

    Oxenkrug, Gregory

    2013-01-01

    Insulin resistance (IR) underlines aging and aging-associated medical (diabetes, obesity, dyslipidemia, hypertension) and psychiatric (depression, cognitive decline) disorders (AAMPD). Molecular mechanisms of IR in genetically or metabolically predisposed individuals remain uncertain. Current review of literature and our data presents the evidences that dysregulation of tryptophan (TRP) – kynurenine (KYN) and KYN – nicotinamide adenine dinucleotide (NAD) metabolic pathways is one of the mecha...

  5. Absorption by DNA single strands of adenine isolated in vacuo: The role of multiple chromophores

    DEFF Research Database (Denmark)

    Nielsen, L.M.; Pedersen, S.O.; Kirketerp, M.-B.S.;

    2012-01-01

    to that for the adenine molecule and the dAMP mononucleotide. Desolvation has little effect on the bandwidth, which implies that inhomogenous broadening of the absorption bands in aqueous solution is of minor importance compared to, e.g., conformational disorder. Finally, at high photon energies, internal conversion...... competes with electron detachment since dissociation of the bare photoexcited ions on the microsecond time scale is measured....

  6. Long-Range Charge Transport in Adenine-Stacked RNA:DNA Hybrids.

    Science.gov (United States)

    Li, Yuanhui; Artés, Juan M; Hihath, Joshua

    2016-01-27

    An extremely important biological component, RNA:DNA can also be used to design nanoscale structures such as molecular wires. The conductance of single adenine-stacked RNA:DNA hybrids is rapidly and reproducibly measured using the break junction approach. The conductance decreases slightly over a large range of molecular lengths, suggesting that RNA:DNA can be used as an oligonucleotide wire. PMID:26596516

  7. Selective self-assembly of adenine-silver nanoparticles forms rings resembling the size of cells

    Science.gov (United States)

    Choi, Sungmoon; Park, Soonyoung; Yang, Seon-Ah; Jeong, Yujin; Yu, Junhua

    2015-12-01

    Self-assembly has played critical roles in the construction of functional nanomaterials. However, the structure of the macroscale multicomponent materials built by the self-assembly of nanoscale building blocks is hard to predict due to multiple intermolecular interactions of great complexity. Evaporation of solvents is usually an important approach to induce kinetically stable assemblies of building blocks with a large-scale specific arrangement. During such a deweting process, we tried to monitor the possible interactions between silver nanoparticles and nucleobases at a larger scale by epifluorescence microscopy, thanks to the doping of silver nanoparticles with luminescent silver nanodots. ssDNA oligomer-stabilized silver nanoparticles and adenine self-assemble to form ring-like compartments similar to the size of modern cells. However, the silver ions only dismantle the self-assembly of adenine. The rings are thermodynamically stable as the drying process only enrich the nanoparticles-nucleobase mixture to a concentration that activates the self-assembly. The permeable membrane-like edge of the ring is composed of adenine filaments glued together by silver nanoparticles. Interestingly, chemicals are partially confined and accumulated inside the ring, suggesting that this might be used as a microreactor to speed up chemical reactions during a dewetting process.

  8. L-Arginine Intake Effect on Adenine Nucleotide Metabolism in Rat Parenchymal and Reproductive Tissues

    Directory of Open Access Journals (Sweden)

    G. Kocic

    2012-01-01

    Full Text Available L-arginine is conditionally essetcial amino acid, required for normal cell growth, protein synthesis, ammonia detoxification, tissue growth and general performance, proposed in the treatment of men sterility and prevention of male impotence. The aim of the present paper was to estimate the activity of the enzymes of adenine nucleotide metabolism: 5′-nucleotidase (5′-NU, adenosine deaminase (ADA, AMP deaminase, and xanthine oxidase (XO, during dietary intake of L-arginine for a period of four weeks of male Wistar rats. Adenosine concentration in tissues is maintained by the relative activities of the adenosine-producing enzyme, 5′-NU and the adenosine-degrading enzyme-ADA adenosine deaminase. Dietary L-arginine intake directed adenine nucleotide metabolism in liver, kidney, and testis tissue toward the activation of adenosine production, by increased 5′-NU activity and decreased ADA activity. Stimulation of adenosine accumulation could be of importance in mediating arginine antiatherosclerotic, vasoactive, immunomodulatory, and antioxidant effects. Assuming that the XO activity reflects the rate of purine catabolism in the cell, while the activity of AMP deaminase is of importance in ATP regeneration, reduced activity of XO, together with the increased AMP-deaminase activity, may suggest that adenine nucleotides are presumably directed to the ATP regenerating process during dietary L-arginine intake.

  9. Interaction of an adenine molecule with a Ag-terminated Si(111) surface

    International Nuclear Information System (INIS)

    The adsorption of an adenine molecule, one of four DNA bases, on a Ag/Si(111) √3 x √3 surface is investigated using a first-principles total-energy calculation. Extensive search of the adsorption structures reveals that two structures are energetically competing. One is a structure with a hexagonal ring of adenine on a large Ag triangle (LT) of the substrate. The molecular plane is inclined at a tilt angle of 10.2 .deg. with respect to the surface plane due to weak bonds between N and substrate Ag atoms. The other is a structure with N just above a Ag atom (T) with the molecular plane vertical to the surface. The N... Ag bond energy in the LT structure is of similar magnitude to the N...H hydrogen bonds of an adenine dimer. The local-density approximation (LDA) and the generalized-gradient approximation (GGA) produce different energy orders between the LT and the T structures. An incorrect treatment of the van der Waals interaction in the density-functional theory could be the origin of the difference.

  10. Spectroscopic assessment of argon gas discharge induced radiolysis of aqueous adenine and thymine

    International Nuclear Information System (INIS)

    Ionizing radiation influences life profoundly for it can modify genetic materials. It is a long-standing task to investigate the interaction between energetic particles and DNA together with its components such as nucleotides, nucleosides and bases so as to predict and assess the potential biological effects. In this study, argon gas discharge was employed to produce energetic ions and electrons. The gas discharge caused the radiolysis of aqueous bases and the involved reactions were analyzed by means of spectroscopic tools including UV-vis absorption, fluorescence and Fourier transformation infrared (FTIR) spectroscopy, also assisted by liquid chromatography/mass spectrometry (LC/MS). It was found that the discharge resulted in the adenine-derived lesions such as 4,6-diamino-5-formamidopyrimidine, 8-OH-Ade and 2-OH-Ade in the radiolysis of aqueous adenine, as well as the thymine-derived lesions such as thymine glycol, 5-hydroxy-6-hydrothymine and/or 6-hydroxy-5-hydrothymine, 5-hydroxymethyluracil and 5-formyluracil in the radiolysis of aqueous thymine. The study of radio-sensitivity showed that adenine was more resistant to the discharge. The mechanisms of the involved reactions were studied in detail, confirming that the hydroxyl radical played a dominant role. - Highlights: → Effective new way to study radiolysis of bases via a home-made argon discharge apparatus. → Quantitative analysis of base radiolysis employing spectroscopic tools combined with HPLC/MS. Discovery of different radiolysis effect compared with other forms of ionizing radiations.

  11. Spectroscopic assessment of argon gas discharge induced radiolysis of aqueous adenine and thymine

    Energy Technology Data Exchange (ETDEWEB)

    Su Xi [Key Laboratory of Ion Beam Bio-engineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences, P.O. Box 1138, Shushanhu Road 350, Hefei 230031 (China); Huang Qing, E-mail: huangq@ipp.ac.cn [Key Laboratory of Ion Beam Bio-engineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences, P.O. Box 1138, Shushanhu Road 350, Hefei 230031 (China); Dang Bingrong [Institute of Modern Physics, Chinese Academy of Sciences, 509 Nanchang Road, Lanzhou 730000 (China); Wang Xiangqin; Yu Zengliang [Key Laboratory of Ion Beam Bio-engineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences, P.O. Box 1138, Shushanhu Road 350, Hefei 230031 (China)

    2011-12-15

    Ionizing radiation influences life profoundly for it can modify genetic materials. It is a long-standing task to investigate the interaction between energetic particles and DNA together with its components such as nucleotides, nucleosides and bases so as to predict and assess the potential biological effects. In this study, argon gas discharge was employed to produce energetic ions and electrons. The gas discharge caused the radiolysis of aqueous bases and the involved reactions were analyzed by means of spectroscopic tools including UV-vis absorption, fluorescence and Fourier transformation infrared (FTIR) spectroscopy, also assisted by liquid chromatography/mass spectrometry (LC/MS). It was found that the discharge resulted in the adenine-derived lesions such as 4,6-diamino-5-formamidopyrimidine, 8-OH-Ade and 2-OH-Ade in the radiolysis of aqueous adenine, as well as the thymine-derived lesions such as thymine glycol, 5-hydroxy-6-hydrothymine and/or 6-hydroxy-5-hydrothymine, 5-hydroxymethyluracil and 5-formyluracil in the radiolysis of aqueous thymine. The study of radio-sensitivity showed that adenine was more resistant to the discharge. The mechanisms of the involved reactions were studied in detail, confirming that the hydroxyl radical played a dominant role. - Highlights: > Effective new way to study radiolysis of bases via a home-made argon discharge apparatus. > Quantitative analysis of base radiolysis employing spectroscopic tools combined with HPLC/MS. > Discovery of different radiolysis effect compared with other forms of ionizing radiations.

  12. 5-azacytidine and purine nucleotide synthesis in guinea-pig cerebral cortex slices by salvage pathway from adenine

    International Nuclear Information System (INIS)

    The effect of the cytostatic, immunosuppressive and antiviral drug 5-azacytidine was studied on the synthesis of purine nucleotides and the total RNA fraction by the salvage pathway of adenine in in vitro experiments on slices from the brain cortex while the azapyrimidine nucleoside only decreased the specific radioactivity of nucleotide adenine and quanine in a relatively high resulting concentration (10-2M), no differences were found between the slices of the brain cortex incubated with and without 5-azacytidine. The comparison of the specific radioactivities of adenine of the total RNA fraction gave a similar picture. No substantial differences were observed between the levels of adenine nucleotides and the total RNA fraction in slices incubated with and without 5-azacytidine. (author)

  13. Thermodynamic Potential for the Abiotic Synthesis of Adenine, Cytosine, Guanine, Thymine, Uracil, Ribose, and Deoxyribose in Hydrothermal Systems

    NARCIS (Netherlands)

    LaRowe, D.E.; Regnier, P.

    2008-01-01

    The thermodynamic potential for the abiotic synthesis of the five common nucleobases (adenine, cytosine, guanine, thymine, and uracil) and two monosaccharides (ribose and deoxyribose) from formaldehyde and hydrogen cyanide has been quantified under temperature, pressure, and bulk composition conditi

  14. Effect of gum arabic on oxidative stress and inflammation in adenine-induced chronic renal failure in rats.

    Directory of Open Access Journals (Sweden)

    Badreldin H Ali

    Full Text Available Inflammation and oxidative stress are known to be involved in the pathogenesis of chronic kidney disease in humans, and in chronic renal failure (CRF in rats. The aim of this work was to study the role of inflammation and oxidative stress in adenine-induced CRF and the effect thereon of the purported nephroprotective agent gum arabic (GA. Rats were divided into four groups and treated for 4 weeks as follows: control, adenine in feed (0.75%, w/w, GA in drinking water (15%, w/v and adenine+GA, as before. Urine, blood and kidneys were collected from the rats at the end of the treatment for analysis of conventional renal function tests (plasma creatinine and urea concentration. In addition, the concentrations of the pro-inflammatory cytokine TNF-α and the oxidative stress markers glutathione and superoxide dismutase, renal apoptosis, superoxide formation and DNA double strand break frequency, detected by immunohistochemistry for γ-H2AX, were measured. Adenine significantly increased the concentrations of urea and creatinine in plasma, significantly decreased the creatinine clearance and induced significant increases in the concentration of the measured inflammatory mediators. Further, it caused oxidative stress and DNA damage. Treatment with GA significantly ameliorated these actions. The mechanism of the reported salutary effect of GA in adenine-induced CRF is associated with mitigation of the adenine-induced inflammation and generation of free radicals.

  15. Prolonged Pulmonary Exposure to Diesel Exhaust Particles Exacerbates Renal Oxidative Stress, Inflammation and DNA Damage in Mice with Adenine-Induced Chronic Renal Failure

    Directory of Open Access Journals (Sweden)

    Abderrahim Nemmar

    2016-05-01

    Full Text Available Background/Aims: Epidemiological evidence indicates that patients with chronic kidney diseases have increased susceptibility to adverse outcomes related to long-term exposure to particulate air pollution. However, mechanisms underlying these effects are not fully understood. Methods: Presently, we assessed the effect of prolonged exposure to diesel exhaust particles (DEP on chronic renal failure induced by adenine (0.25% w/w in feed for 4 weeks, which is known to involve inflammation and oxidative stress. DEP (0.5m/kg was intratracheally (i.t. instilled every 4th day for 4 weeks (7 i.t. instillation. Four days following the last exposure to either DEP or saline (control, various renal endpoints were measured. Results: While body weight was decreased, kidney weight increased in DEP+adenine versus saline+adenine or DEP. Water intake, urine volume, relative kidney weight were significantly increased in adenine+DEP versus DEP and adenine+saline versus saline. Plasma creatinine and urea increased and creatinine clearance decreased in adenine+DEP versus DEP and adenine+saline versus saline. Tumor necrosis factor α, lipid peroxidation and reactive oxygen species were significantly increased in adenine+DEP compared with either DEP or adenine+saline. The antioxidant calase was significantly decreased in adenine+DEP compared with either adenine+saline or DEP. Notably, renal DNA damage was significantly potentiated in adenine+DEP compared with either adenine+saline or DEP. Similarly, systolic blood pressure was increased in adenine+DEP versus adenine+saline or DEP, and in DEP versus saline. Histological evaluation revealed more collagen deposition, higher number of necrotic cell counts and dilated tubules, cast formation and collapsing glomeruli in adenine+DEP versus adenine+saline or DEP. Conclusion: Prolonged pulmonary exposure to diesel exhaust particles worsen renal oxidative stress, inflammation and DNA damage in mice with adenine-induced chronic

  16. Fragmentation of the adenine and guanine molecules induced by electron collisions

    Energy Technology Data Exchange (ETDEWEB)

    Minaev, B. F., E-mail: bfmin@rambler.ru, E-mail: boris@theochem.kth.se [Bohdan Khmelnitsky National University, 18031 Cherkasy (Ukraine); Tomsk State University, 634050 Tomsk (Russian Federation); Shafranyosh, M. I.; Svida, Yu. Yu; Sukhoviya, M. I.; Shafranyosh, I. I. [Uzhgorod National University, 88000 Uzhgorod (Ukraine); Baryshnikov, G. V.; Minaeva, V. A. [Bohdan Khmelnitsky National University, 18031 Cherkasy (Ukraine)

    2014-05-07

    Secondary electron emission is the most important stage in the mechanism of radiation damage to DNA biopolymers induced by primary ionizing radiation. These secondary electrons ejected by the primary electron impacts can produce further ionizations, initiating an avalanche effect, leading to genome damage through the energy transfer from the primary objects to sensitive biomolecular targets, such as nitrogenous bases, saccharides, and other DNA and peptide components. In this work, the formation of positive and negative ions of purine bases of nucleic acids (adenine and guanine molecules) under the impact of slow electrons (from 0.1 till 200 eV) is studied by the crossed electron and molecular beams technique. The method used makes it possible to measure the molecular beam intensity and determine the total cross-sections for the formation of positive and negative ions of the studied molecules, their energy dependences, and absolute values. It is found that the maximum cross section for formation of the adenine and guanine positive ions is reached at about 90 eV energy of the electron beam and their absolute values are equal to 2.8 × 10{sup −15} and 3.2 × 10{sup −15} cm{sup 2}, respectively. The total cross section for formation of the negative ions is 6.1 × 10{sup −18} and 7.6 × 10{sup −18} cm{sup 2} at the energy of 1.1 eV for adenine and guanine, respectively. The absolute cross-section values for the molecular ions are measured and the cross-sections of dissociative ionization are determined. Quantum chemical calculations are performed for the studied molecules, ions and fragments for interpretation of the crossed beams experiments.

  17. Dynamic simulation and metabolome analysis of long-term erythrocyte storage in adenine-guanosine solution.

    Directory of Open Access Journals (Sweden)

    Taiko Nishino

    Full Text Available Although intraerythrocytic ATP and 2,3-bisphophoglycerate (2,3-BPG are known as direct indicators of the viability of preserved red blood cells and the efficiency of post-transfusion oxygen delivery, no current blood storage method in practical use has succeeded in maintaining both these metabolites at high levels for long periods. In this study, we constructed a mathematical kinetic model of comprehensive metabolism in red blood cells stored in a recently developed blood storage solution containing adenine and guanosine, which can maintain both ATP and 2,3-BPG. The predicted dynamics of metabolic intermediates in glycolysis, the pentose phosphate pathway, and purine salvage pathway were consistent with time-series metabolome data measured with capillary electrophoresis time-of-flight mass spectrometry over 5 weeks of storage. From the analysis of the simulation model, the metabolic roles and fates of the 2 major additives were illustrated: (1 adenine could enlarge the adenylate pool, which maintains constant ATP levels throughout the storage period and leads to production of metabolic waste, including hypoxanthine; (2 adenine also induces the consumption of ribose phosphates, which results in 2,3-BPG reduction, while (3 guanosine is converted to ribose phosphates, which can boost the activity of upper glycolysis and result in the efficient production of ATP and 2,3-BPG. This is the first attempt to clarify the underlying metabolic mechanism for maintaining levels of both ATP and 2,3-BPG in stored red blood cells with in silico analysis, as well as to analyze the trade-off and the interlock phenomena between the benefits and possible side effects of the storage-solution additives.

  18. The effect of pi-stacking, h-bonding, and electrostatic interactions on the ionization energies of nucleic acid bases: adenine-adenine, thymine-thymine and adenine-thymine dimers

    Energy Technology Data Exchange (ETDEWEB)

    Bravaya, Ksenia B.; Kostko, Oleg; Ahmed, Musahid; Krylov, Anna I.

    2009-09-02

    A combined theoretical and experimental study of the ionized dimers of thymine and adenine, TT, AA, and AT, is presented. Adiabatic and vertical ionization energies(IEs) for monomers and dimers as well as thresholds for the appearance of the protonated species are reported and analyzed. Non-covalent interactions stronglyaffect the observed IEs. The magnitude and the nature of the effect is different for different isomers of the dimers. The computations reveal that for TT, the largestchanges in vertical IEs (0.4 eV) occur in asymmetric h-bonded and symmetric pi- stacked isomers, whereas in the lowest-energy symmetric h-bonded dimer the shiftin IEs is much smaller (0.1 eV). The origin of the shift and the character of the ionized states is different in asymmetric h-bonded and symmetric stacked isomers. Inthe former, the initial hole is localized on one of the fragments, and the shift is due to the electrostatic stabilization of the positive charge of the ionized fragment by thedipole moment of the neutral fragment. In the latter, the hole is delocalized, and the change in IE is proportional to the overlap of the fragments' MOs. The shifts in AAare much smaller due to a less effcient overlap and a smaller dipole moment. The ionization of the h-bonded dimers results in barrierless (or nearly barrierless) protontransfer, whereas the pi-stacked dimers relax to structures with the hole stabilized by the delocalization or electrostatic interactions.

  19. The structure, stability, H-bonding pattern, and electrostatic potential of adenine tetrads

    Science.gov (United States)

    Gu, Jiande; Leszczynski, Jerzy

    2001-03-01

    Two conformations of the adenine tetrad were investigated at the HF and B3LYP/6-311G(d,p) levels of theory. Both conformations are predicted to be stable only in the nonplanar form. They adopt the bowl type structure. Since the planar form offers better geometry for stacking with the adjacent G-tetrad, both planar forms are expected to be important in the formation of the tetraplexes. Based on electrostatic potential map the positive electrostatic potential in the central area of both conformations is expected to reinforce the stacking between the A-tetrads and the G-tetrads in the tetraplexes.

  20. Fabrication of a Complex Two-Dimensional Adenine-Perylene-3,4,9, 10-tetracarboxylic Dianhydride Chiral Nanoarchitecture through Molecular Self-Assembly

    OpenAIRE

    Sun, Xiaonan; Mura, Manuela; Jonkman, Harry T.; Kantorovich, Lev N.; Silly, Fabien

    2012-01-01

    The two-dimensional self-assembly of a nonsyrnmetric adenine DNA base mixed with symmetric perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) molecules is investigated using scanning tunneling microscopy (STM). We experimentally observe that these two building blocks form a complex close-packed chiral supramolecular network on Au(111). The unit cell of the adenine PTCDA nanoarchitecture is composed of 14 molecules. The high stability of this structure relies on PTCDA-PTCDA and PTCDA-adenin...

  1. Synthesis, spectroscopic, structural and thermal characterizations of vanadyl(IV) adenine complex prospective as antidiabetic drug agent

    Science.gov (United States)

    El-Megharbel, Samy M.; Hamza, Reham Z.; Refat, Moamen S.

    2015-01-01

    The vanadyl(IV) adenine complex; [VO(Adn)2]ṡSO4; was synthesized and characterized. The molar conductivity of this complex was measured in DMSO solution that showed an electrolyte nature. Spectroscopic investigation of the green solid complex studied here indicate that the adenine acts as a bidentate ligand, coordinated to vanadyl(IV) ions through the nitrogen atoms N7 and nitrogen atom of amino group. Thus, from the results presented the vanadyl(IV) complex has square pyramid geometry. Further characterizations using thermal analyses and scanning electron techniques was useful. The aim of this paper was to introduce a new drug model for the diabetic complications by synthesized a novel mononuclear vanadyl(IV) adenine complex to mimic insulin action and reducing blood sugar level. The antidiabetic ability of this complex was investigated in STZ-induced diabetic mice. The results suggested that VO(IV)/adenine complex has antidiabetic activity, it improved the lipid profile, it improved liver and kidney functions, also it ameliorated insulin hormone and blood glucose levels. The vanadyl(IV) complex possesses an antioxidant activity and this was clear through studying SOD, CAT, MDA, GSH and methionine synthase. The current results support the therapeutic potentiality of vanadyl(IV)/adenine complex for the management and treatment of diabetes.

  2. Flavin adenine dinucleotide content of quinone reductase 2: analysis and optimization for structure-function studies.

    Science.gov (United States)

    Leung, Kevin Ka Ki; Litchfield, David W; Shilton, Brian H

    2012-01-01

    Quinone reductase 2 (NQO2) is a broadly expressed enzyme implicated in responses to a number of compounds, including protein kinase inhibitors, resveratrol, and antimalarial drugs. NQO2 includes a flavin adenine dinucleotide (FAD) cofactor, but X-ray crystallographic analysis of human NQO2 expressed in Escherichia coli showed that electron density for the isoalloxazine ring of FAD was weak and there was no electron density for the adenine mononucleotide moiety. Reversed-phase high-performance liquid chromatography (HPLC) of the NQO2 preparation indicated that FAD was not present and only 38% of the protomers contained flavin mononucleotide (FMN), explaining the weak electron density for FAD in the crystallographic analysis. A method for purifying NQO2 and reconstituting with FAD such that the final content approaches 100% occupancy with FAD is presented here. The enzyme prepared in this manner has a high specific activity, and there is strong electron density for the FAD cofactor in the crystal structure. Analysis of NQO2 crystal structures present in the Protein Data Bank indicates that many may have sub-stoichiometric cofactor content and/or contain FMN rather than FAD. This method of purification and reconstitution will help to optimize structural and functional studies of NQO2 and possibly other flavoproteins.

  3. Thymine- and Adenine-Functionalized Polystyrene Form Self-Assembled Structures through Multiple Complementary Hydrogen Bonds

    Directory of Open Access Journals (Sweden)

    Yu-Shian Wu

    2014-06-01

    Full Text Available In this study, we investigated the self-assembly of two homopolymers of the same molecular weight, but containing complementary nucleobases. After employing nitroxide-mediated radical polymerization to synthesize poly(vinylbenzyl chloride, we converted the polymer into poly(vinylbenzyl azide through a reaction with NaN3 and then performed click chemistry with propargyl thymine and propargyl adenine to yield the homopolymers, poly(vinylbenzyl triazolylmethyl methylthymine (PVBT and poly(vinylbenzyl triazolylmethyl methyladenine (PVBA, respectively. This PVBT/PVBA blend system exhibited a single glass transition temperature over the entire range of compositions, indicative of a miscible phase arising from the formation of multiple strong complementary hydrogen bonds between the thymine and adenine groups of PVBT and PVBA, respectively; Fourier transform infrared and 1H nuclear magnetic resonance spectroscopy confirmed the presence of these noncovalent interactions. In addition, dynamic rheology, dynamic light scattering and transmission electron microscopy provided evidence for the formation of supramolecular network structures in these binary PVBT/PVBA blend systems.

  4. Development of bright fluorescent quadracyclic adenine analogues: TDDFT-calculation supported rational design

    Science.gov (United States)

    Foller Larsen, Anders; Dumat, Blaise; Wranne, Moa S.; Lawson, Christopher P.; Preus, Søren; Bood, Mattias; Gradén, Henrik; Marcus Wilhelmsson, L.; Grøtli, Morten

    2015-07-01

    Fluorescent base analogues (FBAs) comprise a family of increasingly important molecules for the investigation of nucleic acid structure and dynamics. We recently reported the quantum chemical calculation supported development of four microenvironment sensitive analogues of the quadracyclic adenine (qA) scaffold, the qANs, with highly promising absorptive and fluorescence properties that were very well predicted by TDDFT calculations. Herein, we report on the efficient synthesis, experimental and theoretical characterization of nine novel quadracyclic adenine derivatives. The brightest derivative, 2-CNqA, displays a 13-fold increased brightness (ɛΦF = 4500) compared with the parent compound qA and has the additional benefit of being a virtually microenvironment-insensitive fluorophore, making it a suitable candidate for nucleic acid incorporation and use in quantitative FRET and anisotropy experiments. TDDFT calculations, conducted on the nine novel qAs a posteriori, successfully describe the relative fluorescence quantum yield and brightness of all qA derivatives. This observation suggests that the TDDFT-based rational design strategy may be employed for the development of bright fluorophores built up from a common scaffold to reduce the otherwise costly and time-consuming screening process usually required to obtain useful and bright FBAs.

  5. Probing ultrafast dynamics in adenine with mid-UV four-wave mixing spectroscopies.

    Science.gov (United States)

    West, Brantley A; Womick, Jordan M; Moran, Andrew M

    2011-08-11

    Heterodyne-detected transient grating (TG) and two-dimensional photon echo (2DPE) spectroscopies are extended to the mid-UV spectral range in this investigation of photoinduced relaxation processes of adenine in aqueous solution. These experiments are the first to combine a new method for generating 25 fs laser pulses (at 263 nm) with the passive phase stability afforded by diffractive optics-based interferometry. We establish a set of conditions (e.g., laser power density, solute concentration) appropriate for the study of dynamics involving the neutral solute. Undesired solute photoionization is shown to take hold at higher peak powers of the laser pulses. Signatures of internal conversion and vibrational cooling dynamics are examined using TG measurements with signal-to-noise ratios as high as 350 at short delay times. In addition, 2DPE line shapes reveal correlations between excitation and emission frequencies in adenine, which reflect electronic and nuclear relaxation processes associated with particular tautomers. Overall, this study demonstrates the feasibility of techniques that will hold many advantages for the study of biomolecules whose lowest-energy electronic resonances are found in the mid-UV (e.g., DNA bases, amino acids). PMID:21756005

  6. Microwave-assisted stereospecific synthesis of novel tetrahydropyran adenine isonucleosides and crystal structures determination

    Science.gov (United States)

    Silva, Fábio P. L.; Cirqueira, Marilia L.; Martins, Felipe T.; Vasconcellos, Mário L. A. A.

    2013-11-01

    We describe in this article stereospecific syntheses for new isonucleosides analogs of adenine 5-7 from tosyl derivatives 2-4 accessing by microwave irradiations (50-80%). The adenine reacts entirely at the N(9) position. Compounds 2-4 were prepared in two steps from the corresponding alcohols 1, 8 and 9 (81-92%). These tetrahydropyrans alcohols 1, 8 and 9 are achiral (Meso compounds) and were prepared in two steps with complete control of 2,4,6-cis relative configuration by Prins cyclization reaction (60-63%) preceded by the Barbier reaction between allyl bromide with benzaldehyde, 4-fluorobenzaldehyde and 2-naphthaldehyde respectively under Lewis acid conditions (96-98%). The configurations and preferential conformations of 5-7 were determined by crystal structure of 6. These novel isonucleosides 5-7 present in silico potentiality to act as GPCR ligand, kinase inhibitor and enzyme inhibitor, evaluated by Molinspiration program, consistent with the expected antiviral and anticancer bioactivities.

  7. High-NaCl diet impairs dynamic renal blood flow autoregulation in rats with adenine-induced chronic renal failure

    DEFF Research Database (Denmark)

    Saeed, Aso; DiBona, Gerald F; Grimberg, Elisabeth;

    2014-01-01

    This study examined the effects of 2 wk of high-NaCl diet on kidney function and dynamic renal blood flow autoregulation (RBFA) in rats with adenine-induced chronic renal failure (ACRF). Male Sprague-Dawley rats received either chow containing adenine or were pair-fed an identical diet without...... increase the susceptibility to hypertensive end-organ injury and progressive renal failure by facilitating pressure transmission to the microvasculature....... adenine (controls). After 10 wk, rats were randomized to either remain on the same diet (0.6% NaCl) or to be switched to high 4% NaCl chow. Two weeks after randomization, renal clearance experiments were performed under isoflurane anesthesia and dynamic RBFA, baroreflex sensitivity (BRS), systolic...

  8. Development of a new model for the induction of chronic kidney disease via intraperitoneal adenine administration, and the effect of treatment with gum acacia thereon.

    Science.gov (United States)

    Al Za'abi, Mohammed; Al Busaidi, Mahfouda; Yasin, Javid; Schupp, Nicole; Nemmar, Abderrahim; Ali, Badreldin H

    2015-01-01

    Oral adenine (0.75% w/w in feed), is an established model for human chronic kidney disease (CKD). Gum acacia (GA) has been shown to be a nephroprotective agent in this model. Here we aimed at developing a new adenine-induced CKD model in rats via a systemic route (intraperitoneal, i.p.) and to test it with GA to obviate the possibility of a physical interaction between GA and adenine in the gut. Adenine was injected i.p. (50 or 100 mg/Kg for four weeks), and GA was given concomitantly in drinking water at a concentration of 15%, w/v. Several plasma and urinary biomarkers of oxidative stress were measured and the renal damage was assessed histopathologically. Adenine, at the two given i.p. doses, significantly reduced body weight, and increased relative kidney weight, water intake and urine output. It dose-dependently increased plasma and urinary inflammatory and oxidative stress biomarkers, and caused morphological and histological damage resembling that which has been reported with oral adenine. Concomitant treatment with GA significantly mitigated almost all the above measured indices. Administration of adenine i.p. induced CKD signs very similar to those induced by oral adenine. Therefore, this new model is quicker, more practical and accurate than the original (oral) model. GA ameliorates the CKD effects caused by adenine given i.p. suggesting that the antioxidant and anti-inflammatory properties possessed by oral GA are the main mechanism for its salutary action in adenine-induced CKD, an action that is independent of its possible interaction with adenine in the gut. PMID:25755826

  9. Development of a new model for the induction of chronic kidney disease via intraperitoneal adenine administration, and the effect of treatment with gum acacia thereon.

    Science.gov (United States)

    Al Za'abi, Mohammed; Al Busaidi, Mahfouda; Yasin, Javid; Schupp, Nicole; Nemmar, Abderrahim; Ali, Badreldin H

    2015-01-01

    Oral adenine (0.75% w/w in feed), is an established model for human chronic kidney disease (CKD). Gum acacia (GA) has been shown to be a nephroprotective agent in this model. Here we aimed at developing a new adenine-induced CKD model in rats via a systemic route (intraperitoneal, i.p.) and to test it with GA to obviate the possibility of a physical interaction between GA and adenine in the gut. Adenine was injected i.p. (50 or 100 mg/Kg for four weeks), and GA was given concomitantly in drinking water at a concentration of 15%, w/v. Several plasma and urinary biomarkers of oxidative stress were measured and the renal damage was assessed histopathologically. Adenine, at the two given i.p. doses, significantly reduced body weight, and increased relative kidney weight, water intake and urine output. It dose-dependently increased plasma and urinary inflammatory and oxidative stress biomarkers, and caused morphological and histological damage resembling that which has been reported with oral adenine. Concomitant treatment with GA significantly mitigated almost all the above measured indices. Administration of adenine i.p. induced CKD signs very similar to those induced by oral adenine. Therefore, this new model is quicker, more practical and accurate than the original (oral) model. GA ameliorates the CKD effects caused by adenine given i.p. suggesting that the antioxidant and anti-inflammatory properties possessed by oral GA are the main mechanism for its salutary action in adenine-induced CKD, an action that is independent of its possible interaction with adenine in the gut.

  10. Progesterone-adenine hybrids as bivalent inhibitors of P-glycoprotein-mediated multidrug efflux: design, synthesis, characterization and biological evaluation.

    Science.gov (United States)

    Zeinyeh, Waël; Mahiout, Zahia; Radix, Sylvie; Lomberget, Thierry; Dumoulin, Axel; Barret, Roland; Grenot, Catherine; Rocheblave, Luc; Matera, Eva-Laure; Dumontet, Charles; Walchshofer, Nadia

    2012-10-01

    Bivalent ligands were designed on the basis of the described close proximity of the ATP-site and the putative steroid-binding site of P-glycoprotein (ABCB1). The syntheses of 19 progesterone-adenine hybrids are described. Their abilities to inhibit P-glycoprotein-mediated daunorubicin efflux in K562/R7 human leukemic cells overexpressing P-glycoprotein were evaluated versus progesterone. The hybrid with a hexamethylene linker chain showed the best inhibitory potency. The efficiency of these progesterone-adenine hybrids depends on two main factors: (i) the nature of the linker and (ii) its attachment point on the steroid skeleton.

  11. Nicotinic acid adenine dinucleotide phosphate-mediated calcium signalling in effector T cells regulates autoimmunity of the central nervous system

    Science.gov (United States)

    Cordiglieri, Chiara; Odoardi, Francesca; Zhang, Bo; Nebel, Merle; Kawakami, Naoto; Klinkert, Wolfgang E. F.; Lodygin, Dimtri; Lühder, Fred; Breunig, Esther; Schild, Detlev; Ulaganathan, Vijay Kumar; Dornmair, Klaus; Dammermann, Werner; Potter, Barry V. L.; Guse, Andreas H.

    2010-01-01

    Nicotinic acid adenine dinucleotide phosphate represents a newly identified second messenger in T cells involved in antigen receptor-mediated calcium signalling. Its function in vivo is, however, unknown due to the lack of biocompatible inhibitors. Using a recently developed inhibitor, we explored the role of nicotinic acid adenine dinucleotide phosphate in autoreactive effector T cells during experimental autoimmune encephalomyelitis, the animal model for multiple sclerosis. We provide in vitro and in vivo evidence that calcium signalling controlled by nicotinic acid adenine dinucleotide phosphate is relevant for the pathogenic potential of autoimmune effector T cells. Live two photon imaging and molecular analyses revealed that nicotinic acid adenine dinucleotide phosphate signalling regulates T cell motility and re-activation upon arrival in the nervous tissues. Treatment with the nicotinic acid adenine dinucleotide phosphate inhibitor significantly reduced both the number of stable arrests of effector T cells and their invasive capacity. The levels of pro-inflammatory cytokines interferon-gamma and interleukin-17 were strongly diminished. Consecutively, the clinical symptoms of experimental autoimmune encephalomyelitis were ameliorated. In vitro, antigen-triggered T cell proliferation and cytokine production were evenly suppressed. These inhibitory effects were reversible: after wash-out of the nicotinic acid adenine dinucleotide phosphate antagonist, the effector T cells fully regained their functions. The nicotinic acid derivative BZ194 induced this transient state of non-responsiveness specifically in post-activated effector T cells. Naïve and long-lived memory T cells, which express lower levels of the putative nicotinic acid adenine dinucleotide phosphate receptor, type 1 ryanodine receptor, were not targeted. T cell priming and recall responses in vivo were not reduced. These data indicate that the nicotinic acid adenine dinucleotide phosphate

  12. Hydroxyl radical reactions with adenine: reactant complexes, transition states, and product complexes.

    Science.gov (United States)

    Cheng, Qianyi; Gu, Jiande; Compaan, Katherine R; Schaefer, Henry F

    2010-10-18

    In order to address problems such as aging, cell death, and cancer, it is important to understand the mechanisms behind reactions causing DNA damage. One specific reaction implicated in DNA oxidative damage is hydroxyl free-radical attack on adenine (A) and other nucleic acid bases. The adenine reaction has been studied experimentally, but there are few theoretical results. In the present study, adenine dehydrogenation at various sites, and the potential-energy surfaces for these reactions, are investigated theoretically. Four reactant complexes [A···OH]* have been found, with binding energies relative to A+OH* of 32.8, 11.4, 10.7, and 10.1 kcal mol(-1). These four reactant complexes lead to six transition states, which in turn lie +4.3, -5.4, (-3.7 and +0.8), and (-2.3 and +0.8) kcal mol(-1) below A+OH*, respectively. Thus the lowest lying [A···OH]* complex faces the highest local barrier to formation of the product (A-H)*+H(2)O. Between the transition states and the products lie six product complexes. Adopting the same order as the reactant complexes, the product complexes [(A-H)···H(2)O]* lie at -10.9, -22.4, (-24.2 and -18.7), and (-20.5 and -17.5) kcal mol(-1), respectively, again relative to separated A+OH*. All six A+OH* → (A-H)*+H(2)O pathways are exothermic, by -0.3, -14.7, (-17.4 and -7.8), and (-13.7 and -7.8) kcal mol(-1), respectively. The transition state for dehydrogenation at N(6) lies at the lowest energy (-5.4 kcal mol(-1) relative to A+OH*), and thus reaction is likely to occur at this site. This theoretical prediction dovetails with the observed high reactivity of OH radicals with the NH(2) group of aromatic amines. However, the high barrier (37.1 kcal mol(-1)) for reaction at the C(8) site makes C(8) dehydrogenation unlikely. This last result is consistent with experimental observation of the imidazole ring opening upon OH radical addition to C(8). In addition, TD-DFT computed electronic transitions of the N(6) product around 420 nm

  13. Few-layer graphene sheets with embedded gold nanoparticles for electrochemical analysis of adenine

    Directory of Open Access Journals (Sweden)

    Biris AR

    2013-04-01

    Full Text Available Alexandru R Biris,1 Stela Pruneanu,1 Florina Pogacean,1 Mihaela D Lazar,1 Gheorghe Borodi,1 Stefania Ardelean,1 Enkeleda Dervishi,2 Fumiya Watanabe,2 Alexandru S Biris2 1National Institute for Research and Development of Isotopic and Molecular Technologies, Cluj-Napoca, Romania; 2Center for Integrative Nanotechnology Sciences, University of Arkansas at Little Rock, Little Rock, AR, USA Abstract: This work describes the synthesis of few-layer graphene sheets embedded with various amounts of gold nanoparticles (Gr-Au-x over an Aux/MgO catalytic system (where x = 1, 2, or 3 wt%. The sheet-like morphology of the Gr-Au-x nanostructures was confirmed by transmission electron microscopy and high resolution transmission electron microscopy, which also demonstrated that the number of layers within the sheets varied from two to seven. The sample with the highest percentage of gold nanoparticles embedded within the graphitic layers (Gr-Au-3 showed the highest degree of crystallinity. This distinct feature, along with the large number of edge-planes seen in high resolution transmission electron microscopic images, has a crucial effect on the electrocatalytic properties of this material. The reaction yields (40%–50% and the final purity (96%–98% of the Gr-Au-x composites were obtained by thermogravimetric analysis. The Gr-Au-x composites were used to modify platinum substrates and subsequently to detect adenine, one of the DNA bases. For the bare electrode, no oxidation signal was recorded. In contrast, all of the modified electrodes showed a strong electrocatalytic effect, and a clear peak for adenine oxidation was recorded at approximately +1.05 V. The highest increase in the electrochemical signal was obtained using a platinum/Gr-Au-3-modified electrode. In addition, this modified electrode had an exchange current density (I0, obtained from the Tafel plot one order of magnitude higher than that of the bare platinum electrode, which also confirmed that

  14. Chronic kidney disease induced by adenine: a suitable model of growth retardation in uremia.

    Science.gov (United States)

    Claramunt, Débora; Gil-Peña, Helena; Fuente, Rocío; García-López, Enrique; Loredo, Vanessa; Hernández-Frías, Olaya; Ordoñez, Flor A; Rodríguez-Suárez, Julián; Santos, Fernando

    2015-07-01

    Growth retardation is a major manifestation of chronic kidney disease (CKD) in pediatric patients. The involvement of the various pathogenic factors is difficult to evaluate in clinical studies. Here, we present an experimental model of adenine-induced CKD for the study of growth failure. Three groups (n = 10) of weaning female rats were studied: normal diet (control), 0.5% adenine diet (AD), and normal diet pair fed with AD (PF). After 21 days, serum urea nitrogen, creatinine, parathyroid hormone (PTH), weight and length gains, femur osseous front advance as an index of longitudinal growth rate, growth plate histomorphometry, chondrocyte proliferative activity, bone structure, aorta calcifications, and kidney histology were analyzed. Results are means ± SE. AD rats developed renal failure (serum urea nitrogen: 70 ± 6 mg/dl and creatinine: 0.6 ± 0.1 mg/dl) and secondary hyperparathyroidism (PTH: 480 ± 31 pg/ml). Growth retardation of AD rats was demonstrated by lower weight (AD rats: 63.3 ± 4.8 g, control rats: 112.6 ± 4.7 g, and PF rats: 60.0 ± 3.8 g) and length (AD rats: 7.2 ± 0.2 cm, control rats: 11.1 ± 0.3 cm, and PF rats: 8.1 ± 0.3 cm) gains as well as lower osseous front advances (AD rats: 141 ± 13 μm/day, control rats: 293 ± 16 μm/day, and PF rats: 251 ± 10 μm/day). The processes of chondrocyte maturation and proliferation were impaired in AD rats, as shown by lower growth plate terminal chondrocyte height (21.7 ± 2.3 vs. 26.2 ± 1.9 and 23.9 ± 1.3 μm in control and PF rats) and proliferative activity index (AD rats: 30 ± 2%, control rats: 38 ± 2%, and PF rats: 42 ± 3%). The bone primary spongiosa structure of AD rats was markedly disorganized. In conclusion, adenine-induced CKD in young rats is associated with growth retardation and disturbed endochondral ossification. This animal protocol may be a useful new experimental model to study growth in CKD.

  15. Modeling the high-energy electronic state manifold of adenine: Calibration for nonlinear electronic spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Nenov, Artur, E-mail: Artur.Nenov@unibo.it; Giussani, Angelo; Segarra-Martí, Javier; Jaiswal, Vishal K. [Dipartimento di Chimica “G. Ciamician,” Università di Bologna, Via Selmi 2, IT-40126 Bologna (Italy); Rivalta, Ivan [Université de Lyon, CNRS, Institut de Chimie de Lyon, École Normale Supérieure de Lyon, 46 Allée d’Italie, F-69364 Lyon Cedex 07 (France); Cerullo, Giulio [Dipartimento di Fisica, Politecnico di Milano, IFN-CNR, Piazza Leonardo Da Vinci 32, IT-20133 Milano (Italy); Mukamel, Shaul [Department of Chemistry, University of California, Irvine, California 92697-2025 (United States); Garavelli, Marco, E-mail: marco.garavelli@unibo.it, E-mail: marco.garavelli@ens-lyon.fr [Dipartimento di Chimica “G. Ciamician,” Università di Bologna, Via Selmi 2, IT-40126 Bologna (Italy); Université de Lyon, CNRS, Institut de Chimie de Lyon, École Normale Supérieure de Lyon, 46 Allée d’Italie, F-69364 Lyon Cedex 07 (France)

    2015-06-07

    Pump-probe electronic spectroscopy using femtosecond laser pulses has evolved into a standard tool for tracking ultrafast excited state dynamics. Its two-dimensional (2D) counterpart is becoming an increasingly available and promising technique for resolving many of the limitations of pump-probe caused by spectral congestion. The ability to simulate pump-probe and 2D spectra from ab initio computations would allow one to link mechanistic observables like molecular motions and the making/breaking of chemical bonds to experimental observables like excited state lifetimes and quantum yields. From a theoretical standpoint, the characterization of the electronic transitions in the visible (Vis)/ultraviolet (UV), which are excited via the interaction of a molecular system with the incoming pump/probe pulses, translates into the determination of a computationally challenging number of excited states (going over 100) even for small/medium sized systems. A protocol is therefore required to evaluate the fluctuations of spectral properties like transition energies and dipole moments as a function of the computational parameters and to estimate the effect of these fluctuations on the transient spectral appearance. In the present contribution such a protocol is presented within the framework of complete and restricted active space self-consistent field theory and its second-order perturbation theory extensions. The electronic excited states of adenine have been carefully characterized through a previously presented computational recipe [Nenov et al., Comput. Theor. Chem. 1040–1041, 295-303 (2014)]. A wise reduction of the level of theory has then been performed in order to obtain a computationally less demanding approach that is still able to reproduce the characteristic features of the reference data. Foreseeing the potentiality of 2D electronic spectroscopy to track polynucleotide ground and excited state dynamics, and in particular its expected ability to provide

  16. On the existence of the H3 tautomer of adenine in aqueous solution. Rationalizations based on hybrid quantum mechanics/molecular mechanics predictions

    DEFF Research Database (Denmark)

    Aidas, Kestutis; Mikkelsen, Kurt V; Kongsted, Jacob

    2010-01-01

    The (15)N NMR spectrum of adenine in aqueous solution has been modeled using high-level combined density functional theory/molecular mechanics techniques coupled to a dynamical averaging scheme. The explicit consideration of the three lowest-energy tautomers of adenine-H9, H7 and H3-allows...

  17. Ultraviolet hypersensitivity of Cockayne syndrome lymphoblastoid lines - the effects of exogenous β-nicotinamide adenine dinucleotide

    International Nuclear Information System (INIS)

    Four Cockayne Syndrome (CS) lymphoblastoid lines were tested for the lethal effects of UV radiation (254 nm) with or without addition of exogenous β-nicotinamide adenine dinucleotide (β-NAD+) to their culture medium. Two of them exhibited a small but significantly increased resistance to UV radiation when β-NAD+ was added to the culture. However, their UV sensitivity after β-NAD+ addition was still much greater than that of normal control lines. Normal control lymphoblastoid lines and those from complementation group A and group C of xeroderma pigmentosum (XP) did not reveal any differences in post-UV sensitivity after the addition of exogenous β-NAD+. Thus the abnormal response to the lethal effects of UV radiation of CS lymphoblastoid lines could not be rectified by β-NAD+ addition. However, β-NAD+ does appear to play some partial role in reducing the high UV sensitivity of some CS lymphoblastoid lines. (author)

  18. Conducting polymer and its composite materials based electrochemical sensor for Nicotinamide Adenine Dinucleotide (NADH).

    Science.gov (United States)

    Omar, Fatin Saiha; Duraisamy, Navaneethan; Ramesh, K; Ramesh, S

    2016-05-15

    Nicotinamide Adenine Dinucleotide (NADH) is an important coenzyme in the human body that participates in many metabolic reactions. The impact of abnormal concentrations of NADH significantly causes different diseases in human body. Electrochemical detection of NADH using bare electrode is a challenging task especially in the presence of main electroactive interferences such as ascorbic acid (AA), uric acid (UA) and dopamine (DA). Modified electrodes have been widely explored to overcome the problems of poor sensitivity and selectivity occurred from bare electrodes. This review gives an overview on the progress of using conducting polymers, polyelectrolyte and its composites (co-polymer, carbonaceous, metal, metal oxide and clay) based modified electrodes for the sensing of NADH. In addition, developments on the fabrication of numerous conducting polymer composites based modified electrodes are clearly described. PMID:26774092

  19. [Absolute bioavailability of the adenine derivative VMA-99-82 possessing antiviral activity].

    Science.gov (United States)

    Smirnova, L A; Suchkov, E A; Riabukha, A F; Kuznetsov, K A; Ozerov, A A

    2013-01-01

    Investigation of the main pharmacokinetic parameters of adenine derivative VMA-99-82 in rats showed large values of the half-life (T1/2 = 11.03 h) and the mean retention time of drug molecules in the organism (MRT = 9.53 h). A high rate of the drug concentration decrease in the plasma determines a small value of the area under the pharmacokinetic curve (AUC = 74.96 mg h/ml). The total distribution volume (V(d) = 10.61 l/kg) is 15.8 times greater than the volume of extracellular fluid in the body of rat, which is indicative of a high ability of VMA-99-82 to be distributed and accumulated in the organs and tissues. The absolute bioavailability of VMA-99-82 is 66%. PMID:24605425

  20. Prebiotic Synthesis of Adenine and Amino Acids Under Europa-like Conditions

    Science.gov (United States)

    Levy, Matthew; Miller, Stanley L.; Brinton, Karen; Bada, Jeffrey L.

    2003-01-01

    In order to simulate prebiotic synthetic processes on Europa and other ice-covered planets and satellites. we have investigated the prebiotic synthesis of organic compounds from dilute solutions of NH4CN frozen for 25 year at -20 and -78 C. In addition the aqueous products of spark discharge reactions from a reducing atmosphere were frozen for 5 years at -20%. We find that both adenine and guanine, as well as a simple set of amino acids dominated by glycine, are produced in substantial yields under these conditions. These results indicate that some of the key components necessary for the origin of life may have been available on Europa throughout its history and suggest that the circumstellar zone where life might arise may be m der than previously thought.

  1. An assessment of the role of DNA adenine methyltransferase on gene expression regulation in E coli.

    Directory of Open Access Journals (Sweden)

    Aswin Sai Narain Seshasayee

    Full Text Available N6-Adenine methylation is an important epigenetic signal, which regulates various processes, such as DNA replication and repair and transcription. In gamma-proteobacteria, Dam is a stand-alone enzyme that methylates GATC sites, which are non-randomly distributed in the genome. Some of these overlap with transcription factor binding sites. This work describes a global computational analysis of a published Dam knockout microarray alongside other publicly available data to throw insights into the extent to which Dam regulates transcription by interfering with protein binding. The results indicate that DNA methylation by DAM may not globally affect gene transcription by physically blocking access of transcription factors to binding sites. Down-regulation of Dam during stationary phase correlates with the activity of TFs whose binding sites are enriched for GATC sites.

  2. Regulation of Salmonella enterica pathogenicity island 1 by DNA adenine methylation.

    Science.gov (United States)

    López-Garrido, Javier; Casadesús, Josep

    2010-03-01

    DNA adenine methylase (Dam(-)) mutants of Salmonella enterica are attenuated in the mouse model and present multiple virulence-related defects. Impaired interaction of Salmonella Dam(-) mutants with the intestinal epithelium has been tentatively correlated with reduced secretion of pathogenicity island 1 (SPI-1) effectors. In this study, we show that S. enterica Dam(-) mutants contain lowered levels of the SPI-1 transcriptional regulators HilA, HilC, HilD, and InvF. Epistasis analysis indicates that Dam-dependent regulation of SPI-1 requires HilD, while HilA, HilC, and InvF are dispensable. A transcriptional hilDlac fusion is expressed at similar levels in Dam(+) and Dam(-) hosts. However, lower levels of hilD mRNA are found in a Dam(-) background, thus providing unsuspected evidence that Dam methylation might exert post-transcriptional regulation of hilD expression. This hypothesis is supported by the following lines of evidence: (i) lowered levels of hilD mRNA are found in Salmonella Dam(-) mutants when hilD is transcribed from a heterologous promoter; (ii) increased hilD mRNA turnover is observed in Dam(-) mutants; (iii) lack of the Hfq RNA chaperone enhances hilD mRNA instability in Dam(-) mutants; and (iv) lack of the RNA degradosome components polynucleotide phosphorylase and ribonuclease E suppresses hilD mRNA instability in a Dam(-) background. Our report of Dam-dependent control of hilD mRNA stability suggests that DNA adenine methylation plays hitherto unknown roles in post-transcriptional control of gene expression.

  3. Expanding antitumor therapeutic windows by targeting cancer-specific nicotinamide adenine dinucleotide phosphate-biogenesis pathways

    Directory of Open Access Journals (Sweden)

    Chakrabarti G

    2015-03-01

    Full Text Available Gaurab Chakrabarti,1,2,4 David E Gerber,3,4 David A Boothman1,2,4 1Department of Pharmacology, 2Department of Radiation Oncology, 3Division of Hematology and Oncology, 4Harold C Simmons Comprehensive Cancer Center, UT Southwestern Medical Center, Dallas, TX, USA Abstract: Nicotinamide adenine dinucleotide phosphate (NADPH biogenesis is an essential mechanism by which both normal and cancer cells maintain redox balance. While antitumor approaches to treat cancers through elevated reactive oxygen species (ROS are not new ideas, depleting specific NADPH-biogenesis pathways that control recovery and repair pathways are novel, viable approaches to enhance cancer therapy. However, to elicit efficacious therapies exploiting NADPH-biogenic pathways, it is crucial to understand and specifically define the roles of NADPH-biogenesis pathways used by cancer cells for survival or recovery from cell stress. It is equally important to select NADPH-biogenic pathways that are expendable or not utilized in normal tissue to avoid unwanted toxicity. Here, we address recent literature that demonstrates specific tumor-selective NADPH-biogenesis pathways that can be exploited using agents that target specific cancer cell pathways normally not utilized in normal cells. Defining NADPH-biogenesis profiles of specific cancer-types should enable novel strategies to exploit these therapeutic windows for increased efficacy against recalcitrant neoplastic disease, such as pancreatic cancers. Accomplishing the goal of using ROS as a weapon against cancer cells will also require agents, such as NQO1 bioactivatable drugs, that selectively induce elevated ROS levels in cancer cells, while normal cells are protected. Keywords: reactive oxygen species (ROS, NQO1-bioactivatable drugs, nicotinamide adenine dinucleotide phosphate (NADPH, glutathione (GSH, biogenic pathways, antioxidant

  4. Affinity chromatography of nicotinamide-adenine dinucleotide-linked dehydrogenases on immobilized derivatives of the dinucleotide.

    Science.gov (United States)

    Barry, S; O'Carra, P

    1973-12-01

    1. Three established methods for immobilization of ligands through primary amino groups promoted little or no attachment of NAD(+) through the 6-amino group of the adenine residue. Two of these methods (coupling to CNBr-activated agarose and to carbodi-imide-activated carboxylated agarose derivatives) resulted instead in attachment predominantly through the ribosyl residues. Other immobilized derivatives were prepared by azolinkage of NAD(+) (probably through the 8 position of the adenine residue) to a number of different spacer-arm-agarose derivatives. 2. The effectiveness of these derivatives in the affinity chromatography of a variety of NAD-linked dehydrogenases was investigated, applying rigorous criteria to distinguish general or non-specific adsorption effects from truly NAD-specific affinity (bio-affinity). The ribosyl-attached NAD(+) derivatives displayed negligible bio-affinity for any of the NAD-linked dehydrogenases tested. The most effective azo-linked derivative displayed strong bio-affinity for glycer-aldehyde 3-phosphate dehydrogenase, weaker bio-affinity for lactate dehydrogenase and none at all for malate dehydrogenase, although these three enzymes have very similar affinities for soluble NAD(+). Alcohol dehydrogenase and xanthine dehydrogenase were subject to such strong non-specific interactions with the hydrocarbon spacer-arm assembly that any specific affinity was completely eclipsed. 3. It is concluded that, in practice, the general effectiveness of a general ligand may be considerably distorted and attenuated by the nature of the immobilization linkage. However, this attenuation can result in an increase in specific effectiveness, allowing dehydrogenases to be separated from one another in a manner unlikely to be feasible if the general effectiveness of the ligand remained intact. 4. The bio-affinity of the various derivatives for lactate dehydrogenase is correlated with the known structure of the NAD(+)-binding site of this enzyme. Problems

  5. Effect of adenine on bacterial translocation using technetium-99m labeled E. coli in an intestinal obstruction model in rats

    International Nuclear Information System (INIS)

    This study aims to investigate effects of adenine on bacterial translocation (BT) using 99mTc-labeled E. coli in an intestinal obstruction rat model. In the study twenty-one rats were used. The rats were divided into three groups according to different feeding patterns. The control group (CG) was fed with a standard chow diet for 7 days. Group A1 and group A2 were fed with adenine supplemented chow diet for 7 days. At the end of the feeding period, after all groups was submitted intestinal obstruction. 99mTc-E. coli was injected into the rats' terminal ileum under anesthetic. The rats were sacrificed under aseptic conditions at 24th h after the surgery. The uptake of 99mTc-E. coli was determined in organs such as the liver, mesenteric lymph nodes, spleen and ileum. Group A1 and group A2 results show that the uptake of 99mTc-E. coli decreased in the blood and organs comparing to the CG. As a result, it was observed that adenine reduced the level of BT when compared with CG. The beneficial effect of adenine on BT in intestinal obstruction was observed. However, further studies are needed to more clearly assess how this benefit can be achieved. (author)

  6. Simultaneous determination of adenine,uridine and adenosine in cordyceps sinensis and its substitutes by LC/ESI-MS

    Institute of Scientific and Technical Information of China (English)

    黄兰芳; 吴名剑; 孙贤军; 郭方遒; 梁逸曾; 李晓如

    2004-01-01

    A simple, sensitive and reproducible high performance liquid chromatography-mass spectrometry coupled with electrospray ionization method for simultaneous separation and determination of adenine, adenosine and uridine was developed. The analytical column is a 2.0 mm× 150 mm Shimadzu VP-ODS column and volume fraction of the mobile phase is 86.5 %water, 12.0%methanol and 1.5%formic acid. 2-chloroadenosine was used as internal standard. Selective ion monitoring mode and selective ion monitoring ions at ratio of mass to electric charge of 136 for adenine, 268 for adenosine and 267 for uridine were chosen for quantitative analysis of the three active components. The results show that the regression equations and linear range are Y=0. 062X+0. 005 and 2.0 - 140.0μg · mL 1for adenine, Y=0. 049X+0. 004 and 4. 0 - 115.0 μg · mL-1 for uridine, Y=0. 154X+0. 014 and 1.0 - 125.0 μg · mL 1 for adenosine. The limits of detection are 0.6 μg · mL 1 for adenine, 1.0μg · mL-1 for uri dine and 0.2 μg · mL 1 for adenosine.The recoveries of the three constituents are from 96.6% to 103.2%.

  7. Effects of Low-Molecular-Weight-Chitosan on the Adenine- Induced Chronic Renal Failure Ratsin vitro andin vivo

    Institute of Scientific and Technical Information of China (English)

    ZHI Xuan; HAN Baoqin; SUI Xianxian; HU Rui; LIU Wanshun

    2015-01-01

    Theeffects of low-molecular-weight-chitosan (LMWC) on chronic renal failure (CRF) rats induced by adenine were investigatedin vivoand in vitro. Chitosan were hydrolyzed using chitosanase at pH 6–7 and 37℃ for 24h to obtain LMWC.In vitro, the effect of LMWC on the proliferation of renal tubular epithelial cells (RTEC) showed that it had no cytotoxic effect and could promote cell growth. For theinvivo experiment, chronic renal failure rats induced by adenine were randomly divided into control group, Niaoduqing group, and high-, medium- and low-dose LMWC groups. For each group, we detected serum creatinine (SCR), blood urea nitrogen (BUN), and total superoxide dismutase (T-SOD), glutathione oxidase (GSH-Px) activities of renal tissue, and obtained the ratio of kidney weight/body weight, pathological changes of kidney. The levels of serum SCR, BUN were higher in the adenine-induced rats than those in the controlgroup, indicating that the rat chronic renal failure model worked successfully. The re-sults after treatment showed that LMWC could reduce the SCR and BUN levels and enhance the activities/levels of T-SOD and GSH-PX in kidney compared to control group. Histopathological examination revealed that adenine-induced renal alterations were restored by LMWC at three tested dosages, especially at the low dosage of 100mgkg−1d−1.

  8. Thermodynamic potential for the abiotic synthesis of Adenine, Cytosine, Guanine, Thymine, Uracil, Ribose, and Deoxyribose in hydrothermal systems

    OpenAIRE

    Larowe, D. E.; Regnier, P.

    2008-01-01

    The thermodynamic potential for the abiotic synthesis of the five common nucleobases (adenine, cytosine, guanine, thymine, and uracil) and two monosaccharides (ribose and deoxyribose) from formaldehyde and hydrogen cyanide has been quantified under temperature, pressure, and bulk composition conditions that are representative of hydrothermal systems. The activities of the precursor molecules (formaldehyde and hydrogen cyanide) required to evaluate the thermodynamics of biomolecule synthesis w...

  9. [Corrective effect of trimethylglycine on the nicotinamide coenzyme and adenine nucleotide content of the tissues in experimental atherosclerosis].

    Science.gov (United States)

    Zapadniuk, V I; Chekman, I S; Panteleĭmonova, T N; Tumanov, V A

    1986-01-01

    Experiments on adult rabbits with experimental atherosclerosis induced by cholesterol (0.25 g/kg for 90 days) showed that chronic administration of trimethylglycine (1.5 g/kg for 30 days) prevented a decrease of the liver and myocardium content of nicotinamide coenzymes and adenine nucleotides. PMID:3758334

  10. Rigid Adenine Nucleoside Derivatives as Novel Modulators of the Human Sodium Symporters for Dopamine and Norepinephrine.

    Science.gov (United States)

    Janowsky, Aaron; Tosh, Dilip K; Eshleman, Amy J; Jacobson, Kenneth A

    2016-04-01

    Thirty-two congeneric rigid adenine nucleoside derivatives containing a North (N)-methanocarba ribose substitution and a 2-arylethynyl group either enhanced (up to 760% of control) or inhibited [(125)I] methyl (1R,2S,3S)-3-(4-iodophenyl)-8-methyl-8-azabicyclo[3.2.1]octane-2-carboxylate (RTI-55) binding at the human dopamine (DA) transporter (DAT) and inhibited DA uptake. Several nucleosides also enhanced [(3)H]mazindol [(±)-5-(4-chlorophenyl)-3,5-dihydro-2H-imidazo[2,1-a]isoindol-5-ol] binding to the DAT. The combination of binding enhancement and functional inhibition suggests possible allosteric interaction with the tropanes. The structure-activity relationship of this novel class of DAT ligands was explored: small N(6)-substition (methyl or ethyl) was favored, while the N1 of the adenine ring was essential. Effective terminal aryl groups include thien-2-yl (compounds 9 and 16), with EC50 values of 35.1 and 9.1 nM, respectively, in [(125)I]RTI-55 binding enhancement, and 3,4-difluorophenyl as in the most potent DA uptake inhibitor (compound 6) with an IC50 value of 92 nM (3-fold more potent than cocaine), but not nitrogen heterocycles. Several compounds inhibited or enhanced binding at the norepinephrine transporter (NET) and serotonin transporter (SERT) and inhibited function in the micromolar range; truncation at the 4'-position in compound 23 allowed for weak inhibition of the SERT. We have not yet eliminated adenosine receptor affinity from this class of DAT modulators, but we identified modifications that remove DAT inhibition as an off-target effect of potent adenosine receptor agonists. Thus, we have identified a new class of allosteric DAT ligands, rigidified adenosine derivatives, and explored their initial structural requirements. They display a very atypical pharmacological profile, i.e., either enhancement by increasing affinity or inhibition of radioligand binding at the DAT, and in some cases the NET and SERT, and inhibition of neurotransmitter

  11. Efficacy of Adenine in the Treatment of Leukopenia and Neutropenia Associated with an Overdose of Antipsychotics or Discontinuation of Lithium Carbonate Administration: Three Case Studies

    Science.gov (United States)

    Tomita, Takashi; Goto, Hidekazu; Sumiya, Kenji; Yoshida, Tadashi; Tanaka, Katsuya; Kohda, Yukinao

    2016-01-01

    Because adenine is effective for managing cases of radiation-induced and drug-induced leukopenia, it may be effective in cases of antipsychotic-induced leukopenia and neutropenia. Here, we report our experience with patients with leukopenia and neutropenia caused by an antipsychotic overdose or discontinuation of lithium carbonate, in whom adenine administration ameliorated the white blood cell and neutrophil counts. The progress of patients suggests that adenine is effective in cases of leukopenia and neutropenia associated with lithium carbonate discontinuation and an antipsychotic overdose. PMID:27776394

  12. Magnitude of malate-aspartate reduced nicotinamide adenine dinucleotide shuttle activity in intact respiring tumor cells.

    Science.gov (United States)

    Greenhouse, W V; Lehninger, A L

    1977-11-01

    Measurements of respiration, CO2 and lactate production, and changes in the levels of various key metabolites of the glycolytic sequence and tricarboxylic acid cycle were made on five lines of rodent ascites tumor cells (two strains of Ehrlich ascites tumor cells, Krebs II carcinoma, AS-30D carcinoma, and L1210 cells) incubated aerobically in the presence of uniformly labeled D-[14C]glucose. From these data, as well as earlier evidence demonstrating that the reduced nicotinamide adenine dinucleotide (NADH) shuttle in these cells requires a transaminase step and is thus identified as the malate-aspartate shuttle (W.V.V. Greenhouse and A.L. Lehninger, Cancer Res., 36: 1392-1396, 1976), metabolic flux diagrams were constructed for the five cell lines. These diagrams show the relative rates of glycolysis, the tricarboxylic acid cycle, electron transport, and the malate-aspartate shuttle in these tumors. Large amounts of cytosolic NADH were oxidized by the mitochondrial respiratory chain via the NADH shuttle, comprising anywhere from about 20 to 80% of the total flow of reducing equivalents to oxygen in these tumors. Calculations of the sources of energy for adenosine triphosphate synthesis indicated that on the average about one-third of the respiratory adenosine triphosphate is generated by electron flow originating from cytosolic NADH via the malate-aspartate shuttle.

  13. Decrease in nicotinamide adenine dinucleotide dehydrogenase is related to skin pigmentation.

    Science.gov (United States)

    Nakama, Mitsuo; Murakami, Yuhko; Tanaka, Hiroshi; Nakata, Satoru

    2012-03-01

    Skin pigmentation is caused by various physical and chemical factors. It might also be influenced by changes in the physiological function of skin with aging. Nicotinamide adenine dinucleotide (NADH) dehydrogenase is an enzyme related to the mitochondrial electron transport system and plays a key role in cellular energy production. It has been reported that the functional decrease in this system causes Parkinson's disease. Another study reports that the amount of NADH dehydrogenase in heart and skeletal muscle decreases with aging. A similar decrease in the skin would probably affect its physiological function. However, no reports have examined the age-related change in levels of NADH dehydrogenase in human skin. In this study, we investigated this change and its effect on skin pigmentation using cultured human epidermal keratinocytes. The mRNA expression of NDUFA1, NDUFB7, and NDUFS2, subunits of NADH dehydrogenase, and its activity were significantly decreased in late passage keratinocytes compared to early passage cells. Conversely, the mRNA expression of melanocyte-stimulating cytokines, interleukin-1 alpha and endothelin 1, was increased in late passage cells. On the other hand, the inhibition of NADH dehydrogenase upregulated the mRNA expression of melanocyte-stimulating cytokines. Moreover, the level of NDUFB7 mRNA was lower in pigmented than in nonpigmented regions of skin in vivo. These results suggest the decrease in NADH dehydrogenase with aging to be involved in skin pigmentation.

  14. DNA adenine methylation is required to replicate both Vibrio cholerae chromosomes once per cell cycle.

    Directory of Open Access Journals (Sweden)

    Gaëlle Demarre

    2010-05-01

    Full Text Available DNA adenine methylation is widely used to control many DNA transactions, including replication. In Escherichia coli, methylation serves to silence newly synthesized (hemimethylated sister origins. SeqA, a protein that binds to hemimethylated DNA, mediates the silencing, and this is necessary to restrict replication to once per cell cycle. The methylation, however, is not essential for replication initiation per se but appeared so when the origins (oriI and oriII of the two Vibrio cholerae chromosomes were used to drive plasmid replication in E. coli. Here we show that, as in the case of E. coli, methylation is not essential for oriI when it drives chromosomal replication and is needed for once-per-cell-cycle replication in a SeqA-dependent fashion. We found that oriII also needs SeqA for once-per-cell-cycle replication and, additionally, full methylation for efficient initiator binding. The requirement for initiator binding might suffice to make methylation an essential function in V. cholerae. The structure of oriII suggests that it originated from a plasmid, but unlike plasmids, oriII makes use of methylation for once-per-cell-cycle replication, the norm for chromosomal but not plasmid replication.

  15. Poly-adenine-based programmable engineering of gold nanoparticles for highly regulated spherical DNAzymes.

    Science.gov (United States)

    Zhu, Dan; Pei, Hao; Chao, Jie; Su, Shao; Aldalbahi, Ali; Rahaman, Mostafizur; Wang, Lihua; Wang, Lianhui; Huang, Wei; Fan, Chunhai; Zuo, Xiaolei

    2015-11-28

    Enzyme complexes are assembled at the two-dimensional lipid membrane or prearranged on three-dimensional scaffolding proteins to regulate their catalytic activity in cells. Inspired by nature, we have developed gold nanoparticle-based spherical DNAzymes (SNAzymes) with programmably engineered activities by exploiting poly-adenine (polyA)-Au interactions. In a SNAzyme, AuNPs serve as the metal core, which is decorated with a functional shell of DNAzymes. Conventional thiolated DNAzyme-based assembly leads to disordered structures with suppressed activity. In contrast, by using an anchoring block of polyA tails, we find that the activity of SNAzymes can be programmably regulated. By using a polyA30 tail, SNAzymes demonstrated remarkably enhanced binding affinity compared to the thiolated DNAzyme-based assembly (∼75-fold) or individual DNAzymes in the solution phase (∼10-fold). More significantly, this increased affinity is directly translated to the sensitivity improvement in the SNAzyme-based lead sensor. Hence, this design of SNAzymes may provide new opportunities for developing biosensors and bioimaging probes for theranostic applications.

  16. Magnitude of malate-aspartate reduced nicotinamide adenine dinucleotide shuttle activity in intact respiring tumor cells.

    Science.gov (United States)

    Greenhouse, W V; Lehninger, A L

    1977-11-01

    Measurements of respiration, CO2 and lactate production, and changes in the levels of various key metabolites of the glycolytic sequence and tricarboxylic acid cycle were made on five lines of rodent ascites tumor cells (two strains of Ehrlich ascites tumor cells, Krebs II carcinoma, AS-30D carcinoma, and L1210 cells) incubated aerobically in the presence of uniformly labeled D-[14C]glucose. From these data, as well as earlier evidence demonstrating that the reduced nicotinamide adenine dinucleotide (NADH) shuttle in these cells requires a transaminase step and is thus identified as the malate-aspartate shuttle (W.V.V. Greenhouse and A.L. Lehninger, Cancer Res., 36: 1392-1396, 1976), metabolic flux diagrams were constructed for the five cell lines. These diagrams show the relative rates of glycolysis, the tricarboxylic acid cycle, electron transport, and the malate-aspartate shuttle in these tumors. Large amounts of cytosolic NADH were oxidized by the mitochondrial respiratory chain via the NADH shuttle, comprising anywhere from about 20 to 80% of the total flow of reducing equivalents to oxygen in these tumors. Calculations of the sources of energy for adenosine triphosphate synthesis indicated that on the average about one-third of the respiratory adenosine triphosphate is generated by electron flow originating from cytosolic NADH via the malate-aspartate shuttle. PMID:198130

  17. Synthesis of adenine, guanine, cytosine, and other nitrogen organic compounds by a Fischer-Tropsch-like process.

    Science.gov (United States)

    Yang, C. C.; Oro, J.

    1971-01-01

    Study of the formation of purines, pyrimidines, and other bases from CO, H2, and NH3 under conditions similar to those used in the Fischer-Tropsch process. It is found that industrial nickel/iron alloy catalyzes the synthesis of adenine, guanine, cytosine, and other nitrogenous compounds from mixtures of CO, H2, and NH3 at temperatures of about 600 C. Sufficient sample was accumulated to isolate as solid products adenine, guanine, and cytosine, which were identified by infrared spectrophotometry. In the absence of nickel/iron catalyst, at 650 C, or in the presence of this catalyst, at 450 C, no purines or pyrimidines were synthesized. These results confirm and extend some of the work reported by Kayatsu et al. (1968).

  18. Conversion of adenine to 5-amino-4-pyrimidinylimidazole caused by acetyl capping during solid phase oligonucleotide synthesis.

    Science.gov (United States)

    Rodriguez, Andrew A; Cedillo, Isaiah; McPherson, Andrew K

    2016-08-01

    The acetyl capping reaction used throughout solid phase oligonucleotide synthesis is meant to minimize n-1 deletionmer impurities by terminating sequences that fail to couple to a phosphoramidite. However, the reaction is also responsible for the formation of a number of impurities. One capping-related impurity has an additional mass of 98amu from the parent oligonucleotide. The n+98 amu impurity was found to result from modification of an adenine nucleobase. The structure of the impurity was determined by preparation of an oligonucleotide enriched in n+98 amu, enzymatic digestion to individual nucleosides, isolation of the pure nucleoside+98 amu species, crystallization, and X-ray crystallographic analysis. The n+98 amu impurity is an oligonucleotide in which one adenine residue has been converted to 5-amino-4-pyrimidinylimidazole. The mechanism of formation of the impurity was investigated, and a mechanism is proposed. PMID:27353533

  19. Ischemic preconditioning protects post-ischemic renal function in anesthetized dogs: role of adenosine and adenine nucleotides

    Institute of Scientific and Technical Information of China (English)

    Fan-zhu LI; Shoji KIMURA; Akira NISHIYAMA; Matlubur RAHMAN; Guo-xing ZHANG; Youichi ABE

    2005-01-01

    Aim: To investigate the effects of renal ischemic preconditioning (IPC) on both renal hemodynamics and the renal interstitial concentrations of adenosine and adenine nucleotides induced by ischemia-reperfusion injury.Methods: Renal hemodynamics responses to ischemia-reperfusion injury in mongrel dog models were determined with or without multiple brief renal ischemic preconditioning treatments, as well as the adenosine A1 receptor antagonist (KW-3902),respectively.The renal interstitial concentrations of adenosine and adenine nucleotides in response to ischemia-reperfusion injury, either following 1-3 cycles of IPC or not, were measured simultaneously using microdialysis sampling technology.Results: One 10-min IPC, adenosine A1 receptor antagonist (KW3902) also shortened the recovery time of renal blood flow (RBF) and urine flow (UF), as well as mean blood pressure (BP).Advanced renal IPC attenuated the increment of adenosine and adenine nucleotides, as well as recovery time during the 60-min reperfusion which followed the 60-min renal ischemia.All of these recovery times were dependent on the cycles of 10-min IPC.The renal interstitial concentrations of adenosine and adenine nucleotides increased and decreased during renal ischemia and reperfusion, respectively.Conclusion: A significant relativity in dog models exists between the cycles of 10-min renal IPC and the recovery time of BP, UF, and RBF during the 60-min renal reperfusion following 60-min renal ischemia, respectively.Renal IPC can protect against ischemiareperfusion injury and the predominant effect of endogenous adenosine induced by prolonged renal ischemia; renal adenosine A1 receptor activation during the renal ischemia-reperfusion injury is detrimental to renal function.

  20. N-6-Adenine-Specific DNA Methyltransferase 1 (N6AMT1) Polymorphisms and Arsenic Methylation in Andean Women

    OpenAIRE

    Harari, Florencia; Engström, Karin; Concha, Gabriela; Colque, Graciela; Vahter, Marie; Broberg, Karin

    2013-01-01

    BACKGROUND: In humans, inorganic arsenic is metabolized to methylated metabolites mainly by arsenic (+3 oxidation state) methyltransferase (AS3MT). AS3MT polymorphisms are associated with arsenic metabolism efficiency. Recently, a putative N-6-adenine-specific DNA methyltransferase 1 (N6AMT1) was found to methylate arsenic in vitro. OBJECTIVE: We evaluated the role of N6AMT1 polymorphisms in arsenic methylation efficiency in humans. METHODS: We assessed arsenic methylation efficiency in 188 w...

  1. Role of Nicotinamide Adenine Dinucleotide Phosphate–Reduced Oxidase Proteins in Pseudomonas aeruginosa–Induced Lung Inflammation and Permeability

    OpenAIRE

    Fu, Panfeng; Mohan, Vijay; Mansoor, Syed; Tiruppathi, Chinnaswamy; Sadikot, Ruxana T.; Natarajan, Viswanathan

    2013-01-01

    Earlier studies indicated a role for reactive oxygen species (ROS) in host defense against Pseudomonas aeruginosa infection. However, the role of nicotinamide adenine dinucleotide phosphate–reduced (NADPH) oxidase (NOX) proteins and the mechanism of activation for NADPH oxidase in P. aeruginosa infection are not well-defined. Here, we investigated the role of NOX2 and NOX4 proteins in P. aeruginosa infection, ROS generation, and endothelial barrier function in murine lungs and in human lung m...

  2. A novel twist on molecular interactions between thioredoxin and nicotinamide adenine dinucleotide phosphate-dependent thioredoxin reductase

    DEFF Research Database (Denmark)

    Kirkensgaard, Kristine Groth; Hägglund, Per; Shahpiri, Azar;

    2013-01-01

    The ubiquitous disulfide reductase thioredoxin (Trx) regulates several important biological processes such as seed germination in plants. Oxidized cytosolic Trx is regenerated by nicotinamide adenine dinucleotide phosphate (NADPH)-dependent thioredoxin reductase (NTR) in a multistep transfer of r....... Overall, the findings suggest that NTR:Trx interactions in different biological systems are fine-tuned by multiple intermolecular contacts. Proteins 2014; 82:607-619. (c) 2013 Wiley Periodicals, Inc....

  3. Back Electron Transfer Suppresses the Periodic Length Dependence of DNA-mediated Charge Transport Across Adenine Tracts

    OpenAIRE

    Genereux, Joseph C.; Augustyn, Katherine E.; Davis, Molly L.; Shao, Fangwei; Barton, Jacqueline K.

    2008-01-01

    DNA-mediated charge transport (CT) is exquisitely sensitive to the integrity of the bridging π-stack and is characterized by a shallow distance dependence. These properties are obscured by poor coupling between the donor/acceptor pair and the DNA bridge, or by convolution with other processes. Previously, we found a surprising periodic length dependence for the rate of DNA-mediated CT across adenine tracts monitored by 2-aminopurine fluorescence. Here we report a similar periodicity by monito...

  4. Purification and characterization of the enzymes involved in nicotinamide adenine dinucleotide degradation by Penicillium brevicompactum NRC 829

    OpenAIRE

    Ali, Thanaa Hamed; El-Ghonemy, Dina Helmy

    2016-01-01

    The present study was conducted to investigate a new pathway for the degradation of nicotinamide adenine dinucleotide (NAD) by Penicillium brevicompactum NRC 829 extracts. Enzymes involved in the hydrolysis of NAD, i.e. alkaline phosphatase, aminohydrolase and glycohydrolase were determined. Alkaline phosphatase was found to catalyse the sequential hydrolysis of two phosphate moieties of NAD molecule to nicotinamide riboside plus adenosine. Adenosine was then deaminated by aminohydrolase to i...

  5. A new microplatform based on titanium dioxide nanofibers/graphene oxide nanosheets nanocomposite modified screen printed carbon electrode for electrochemical determination of adenine in the presence of guanine.

    Science.gov (United States)

    Arvand, Majid; Ghodsi, Navid; Zanjanchi, Mohammad Ali

    2016-03-15

    The current techniques for determining adenine have several shortcomings such as high cost, high time consumption, tedious pretreatment steps and the requirements for highly skilled personnel often restrict their use in routine analytical practice. This paper describes the development and utilization of a new nanocomposite consisting of titanium dioxide nanofibers (TNFs) and graphene oxide nanosheets (GONs) for screen printed carbon electrode (SPCE) modification. The synthesized GONs and TNFs were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). The modified electrode (TNFs/GONs/SPCE) was used for electrochemical characterization of adenine. The TNFs/GONs/SPCE exhibited an increase in peak current and the electron transfer kinetics and decrease in the overpotential for the oxidation reaction of adenine. Using differential pulse voltammetry (DPV), the prepared sensor showed good sensitivity for determining adenine in two ranges from 0.1-1 and 1-10 μM, with a detection limit (DL) of 1.71 nM. Electrochemical studies suggested that the TNFs/GONs/SPCE provided a synergistic augmentation on the voltammetric behavior of electrochemical oxidation of adenine, which was indicated by the improvement of anodic peak current and a decrease in anodic peak potential. The amount of adenine in pBudCE4.1 plasmid was determined via the proposed sensor and the result was in good compatibility with the sequence data of pBudCE4.1 plasmid.

  6. 腺嘌呤致不同性别大鼠骨质疏松的差异%Sex Difference in Osteopenia Induced by Adenine in Rats

    Institute of Scientific and Technical Information of China (English)

    小切间猛史; 田野香; 金原正幸; 高明; 王晓明; 郭义; 张艳军; 郭利平; 石田寅夫

    2005-01-01

    Adenine, which is common and essential to creatures, is widely used in clinical field. However,abundance of adenine is harmful to the living body. So far the male animals have been used for the research on adenine influence. In male rats, feeding of adenine-rich diet induces renal failure. Because of very few studies of adenine influence to female animals, we investigated the influence of adenine treatment between male and female rats and discussed the sex difference on adenine treatment. Young male and female rats were administrated each adjusted adenine (6, 50 and 100 mg/mL) for 8 weeks (3 times/week). In male rats, the renal failure was induced by 100 mg/mL adenine treatment and renal dysfunction was induced by 50 mg/mL adenine treatment. In female rats, however renal dysfunction was induced by 100 mg/mL group only, and that was somewhat different compared to that in male rats.Serum testosterone level and BMD in male rats were decreased by adenine treatment with or without renal dysfunction. On the contrary, serum 17-beta estradiol level and BMD in female rats were not affected by adenine treatment at all regardless of renal dysfunction. As abovementioned, this study could shed light on adenine effect on bone metabolism through sex hormone synthesis. Adenine is commonly contained in clinical medicines and general food. Abundant ingestion of nucleic acid including adenine may affect the internal secretion function.%肌酸尿时多见而又为主要病因的腺嘌呤广泛地应用于临床,但是腺嘌呤过多对人体是有害的.到目前为止,只有应用雄性动物研究腺嘌呤影响的报告.在雄鼠发现喂饲富含腺嘌呤的饲料会引起肾衰竭.由于腺嘌呤对雌性动物的影响的报告还甚少,本实验研究了腺嘌呤处理对不同性别大鼠的影响,并进行了讨论.年轻雄性和雌性大鼠分别给与一种预定浓度的腺嘌呤(6、60及100mg/mL)共8周(3次/周).结果100mg/mL腺嘌呤处理能引起雄鼠肾衰,50mg/m

  7. An alternative membrane transport pathway for phosphate and adenine nucleotides in mitochondria and its possible function.

    Science.gov (United States)

    Reynafarje, B; Lehninger, A L

    1978-10-01

    This paper describes the properties and a possible biological role of a transport process across the inner membrane of rat liver mitochondria resulting in the exchange of ATP(4-) (out) for ADP(3-) (in) + 0.5 phosphate(2-) (in). This transmembrane exchange reaction, designated as the ATP-ADP-phosphate exchange, is specific for the ligands shown, electroneutral, insensitive to N-ethylmaleimide or mersalyl, inhibited by atractyloside, and appears to occur only in the direction as written. It is thus distinct from the well-known phosphate-hydroxide and phosphate-dicarboxylate exchange systems, which are inhibited by mersalyl, and from the ATP-ADP exchanger, which does not transport phosphate. During ATP hydrolysis by mitochondria, half of the phosphate formed from ATP passes from the matrix to the medium by the mersalyl-insensitive ATP-ADP-phosphate exchange and the other half by the well-known mersalyl-sensitive phosphate-hydroxide exchange. These and other considerations have led to a hypothesis for the pathway and stoichiometry of ATP-dependent reverse electron transport, characterized by a requirement of 1.33 molecules of ATP per pair of electrons reversed and by the utilization of a different membrane transport pathway for phosphate and adenine nucleotides than is taken in forward electron flow and oxidative phosphorylation. The possible occurrence of independent pathways for ATP-forming forward electron flow and ATP-consuming reverse electron flow is consonant with the fact that the opposing degradative and synthetic pathways in the central routes of cell metabolism generally have different pathways that are independently regulated.

  8. Electrochemical oxidation of dihydronicotinamide adenine dinucleotide at nitrogen-doped carbon nanotube electrodes.

    Science.gov (United States)

    Goran, Jacob M; Favela, Carlos A; Stevenson, Keith J

    2013-10-01

    Nitrogen-doped carbon nanotubes (N-CNTs) substantially lower the overpotential necessary for dihydronicotinamide adenine dinucleotide (NADH) oxidation compared to nondoped CNTs or traditional carbon electrodes such as glassy carbon (GC). We observe a 370 mV shift in the peak potential (Ep) from GC to CNTs and another 170 mV shift from CNTs to 7.4 atom % N-CNTs in a sodium phosphate buffer solution (pH 7.0) with 2.0 mM NADH (scan rate 10 mV/s). The sensitivity of 7.4 atom % N-CNTs to NADH was measured at 0.30 ± 0.04 A M(-1) cm(-2), with a limit of detection at 1.1 ± 0.3 μM and a linear range of 70 ± 10 μM poised at a low potential of -0.32 V (vs Hg/Hg2SO4). NADH fouling, known to occur to the electrode surface during NADH oxidation, was investigated by measuring both the change in Ep and the resulting loss of electrode sensitivity. NADH degradation, known to occur in phosphate buffer, was characterized by absorbance at 340 nm and correlated with the loss of NADH electroactivity. N-CNTs are further demonstrated to be an effective platform for dehydrogenase-based biosensing by allowing glucose dehydrogenase to spontaneously adsorb onto the N-CNT surface and measuring the resulting electrode's sensitivity to glucose. The glucose biosensor had a sensitivity of 0.032 ± 0.003 A M(-1) cm(-2), a limit of detection at 6 ± 1 μM, and a linear range of 440 ± 50 μM. PMID:23991631

  9. Two adenine nucleotide translocase paralogues involved in cell proliferation and spermatogenesis in the silkworm Bombyx mori.

    Directory of Open Access Journals (Sweden)

    Ryohei Sugahara

    Full Text Available Mitochondrial adenine nucleotide translocase (ANT specifically acts in ADP/ATP exchange through the mitochondrial inner membrane. This transporter protein thereby plays a significant role in energy metabolism in eukaryotic cells. Most mammals have four paralogous ANT genes (ANT1-4 and utilize these paralogues in different types of cells. The fourth paralogue of ANT (ANT4 is present only in mammals and reptiles and is exclusively expressed in testicular germ cells where it is required for meiotic progression in the spermatocytes. Here, we report that silkworms harbor two ANT paralogues, the homeostatic paralogue (BmANTI1 and the testis-specific paralogue (BmANTI2. The BmANTI2 protein has an N-terminal extension in which the positions of lysine residues in the amino acid sequence are distributed as in human ANT4. An expression analysis showed that BmANTI2 transcripts were restricted to the testis, suggesting the protein has a role in the progression of spermatogenesis. By contrast, BmANTI1 was expressed in all tissues tested, suggesting it has an important role in homeostasis. We also observed that cultured silkworm cells required BmANTI1 for proliferation. The ANTI1 protein of the lepidopteran Plutella xylostella (PxANTI1, but not those of other insect species (or PxANTI2, restored cell proliferation in BmANTI1-knockdown cells suggesting that ANTI1 has similar energy metabolism functions across the Lepidoptera. Our results suggest that BmANTI2 is evolutionarily divergent from BmANTI1 and has developed a specific role in spermatogenesis similar to that of mammalian ANT4.

  10. An alternative membrane transport pathway for phosphate and adenine nucleotides in mitochondria and its possible function.

    Science.gov (United States)

    Reynafarje, B; Lehninger, A L

    1978-10-01

    This paper describes the properties and a possible biological role of a transport process across the inner membrane of rat liver mitochondria resulting in the exchange of ATP(4-) (out) for ADP(3-) (in) + 0.5 phosphate(2-) (in). This transmembrane exchange reaction, designated as the ATP-ADP-phosphate exchange, is specific for the ligands shown, electroneutral, insensitive to N-ethylmaleimide or mersalyl, inhibited by atractyloside, and appears to occur only in the direction as written. It is thus distinct from the well-known phosphate-hydroxide and phosphate-dicarboxylate exchange systems, which are inhibited by mersalyl, and from the ATP-ADP exchanger, which does not transport phosphate. During ATP hydrolysis by mitochondria, half of the phosphate formed from ATP passes from the matrix to the medium by the mersalyl-insensitive ATP-ADP-phosphate exchange and the other half by the well-known mersalyl-sensitive phosphate-hydroxide exchange. These and other considerations have led to a hypothesis for the pathway and stoichiometry of ATP-dependent reverse electron transport, characterized by a requirement of 1.33 molecules of ATP per pair of electrons reversed and by the utilization of a different membrane transport pathway for phosphate and adenine nucleotides than is taken in forward electron flow and oxidative phosphorylation. The possible occurrence of independent pathways for ATP-forming forward electron flow and ATP-consuming reverse electron flow is consonant with the fact that the opposing degradative and synthetic pathways in the central routes of cell metabolism generally have different pathways that are independently regulated. PMID:283393

  11. Adenine Nucleotide Translocase 4 Is Expressed Within Embryonic Ovaries and Dispensable During Oogenesis

    Science.gov (United States)

    Lim, Chae Ho; Brower, Jeffrey V.; Resnick, James L.; Oh, S. Paul

    2015-01-01

    Adenine nucleotide translocase (Ant) facilitates the exchange of adenosine triphosphate across the mitochondrial inner membrane and plays a critical role for bioenergetics in eukaryotes. Mice have 3 Ant paralogs, Ant1 (Slc25a4), Ant2 (Slc25a5), and Ant4 (Slc25a31), which are expressed in a tissue-dependent manner. We previously identified that Ant4 was expressed exclusively in testicular germ cells in adult mice and essential for spermatogenesis and subsequently male fertility. Further investigation into the process of spermatogenesis revealed that Ant4 was particularly highly expressed during meiotic prophase I and indispensable for normal progression of leptotene spermatocytes to the stages thereafter. In contrast, the expression and roles of Ant4 in female germ cells have not previously been elucidated. Here, we demonstrate that the Ant4 gene is expressed during embryonic ovarian development during which meiotic prophase I occurs. We confirmed embryonic ovary-specific Ant4 expression using a bacterial artificial chromosome transgene. In contrast to male, however, Ant4 null female mice were fertile although the litter size was slightly decreased. They showed apparently normal ovarian development which was morphologically indistinguishable from the control animals. These data indicate that Ant4 is a meiosis-specific gene expressed during both male and female gametogenesis however indispensable only during spermatogenesis and not oogenesis. The differential effects of Ant4 depletion within the processes of male and female gametogenesis may be explained by meiosis-specific inactivation of the X-linked Ant2 gene in male, a somatic paralog of the Ant4 gene. PMID:25031318

  12. Autoradiographic study on the incorporation of carbon-14 labeled formate and adenine into nucleic acid in blood-forming cells

    International Nuclear Information System (INIS)

    The incorporation of [14C]formate and [8-14C]adenine into nucleic acid in blood-forming cells was studied by the autoradiographic technique. The isotopic markers were injected subcutaneously into young rats weighting from 100 to 150 g three times every 24 hours and the animals were examined 3 hours after the last injection. In the case of [14C]formate injection, erythroblasts exhibited extremely strong labeling in contrast to weaker labeling of other blood-forming cells. In the case of [14C]adenine administration, on the other hand, immature cells of the granuclocytic series as well as immature reticulum cells (proliferating cells of reticular tissue) were much more heavily labeled than were other blood-forming cells, particularly the erythroblasts which revealed weak or no labeling. By digestion or extraction of DNA, RNA or both from cells with DNase, RNase or hot 10% perchloric acid treatment, respectively, it was confirmed that the observed heavy labeling of any type of cells with either [14C]formate or [14C]adenine was due chiefly to incorporation of the radioactive materials into nuclear DNA. The present results are discussed together with the findings of earlier studies on lymphoid cells which indicate that, in certain cell types, the patterns of [3H]deoxycytidine labeling differ considerably from the corresponding patterns of [3H]deoxycytidine labeling. The present and earlier findings provide evidence to substantiate that, among blood-forming cells, there are considerable variations in the labeling patterns of nuclear DNA depending on differences in the radioactive DNA precursors used as well as in the cell types. (author)

  13. Multiple Decay Mechanisms and 2D-UV Spectroscopic Fingerprints of Singlet Excited Solvated Adenine-Uracil Monophosphate.

    Science.gov (United States)

    Li, Quansong; Giussani, Angelo; Segarra-Martí, Javier; Nenov, Artur; Rivalta, Ivan; Voityuk, Alexander A; Mukamel, Shaul; Roca-Sanjuán, Daniel; Garavelli, Marco; Blancafort, Lluís

    2016-05-23

    The decay channels of singlet excited adenine uracil monophosphate (ApU) in water are studied with CASPT2//CASSCF:MM potential energy calculations and simulation of the 2D-UV spectroscopic fingerprints with the aim of elucidating the role of the different electronic states of the stacked conformer in the excited state dynamics. The adenine (1) La state can decay without a barrier to a conical intersection with the ground state. In contrast, the adenine (1) Lb and uracil S(U) states have minima that are separated from the intersections by sizeable barriers. Depending on the backbone conformation, the CT state can undergo inter-base hydrogen transfer and decay to the ground state through a conical intersection, or it can yield a long-lived minimum stabilized by a hydrogen bond between the two ribose rings. This suggests that the (1) Lb , S(U) and CT states of the stacked conformer may all contribute to the experimental lifetimes of 18 and 240 ps. We have also simulated the time evolution of the 2D-UV spectra and provide the specific fingerprint of each species in a recommended probe window between 25 000 and 38 000 cm(-1) in which decongested, clearly distinguishable spectra can be obtained. This is expected to allow the mechanistic scenarios to be discerned in the near future with the help of the corresponding experiments. Our results reveal the complexity of the photophysics of the relatively small ApU system, and the potential of 2D-UV spectroscopy to disentangle the photophysics of multichromophoric systems. PMID:27113273

  14. Photochemical decoration of gold nanoparticles on polymer stabilized magnetic microspheres for determination of adenine by surface-enhanced Raman spectroscopy

    International Nuclear Information System (INIS)

    Magnetic microspheres decorated with gold nanoparticles (AuNPs) were prepared and used for the determination of adenine by surface-enhanced Raman scattering (SERS). Magnetic particles were first synthesized by coprecipitation of solutions containing iron(II) and iron(III) ions with ammonium hydroxide. Subsequently, the magnetic particles were suspended into a solution of poly(divinylbenzene-co-methyl methacrylate) to yield polymer-stabilized magnetic microspheres. These were further decorated with AuNPs via a new photochemical reduction method. The magnetic microspheres were characterized by XRD patterns and SEM images. They are shown to represent highly SERS-active substrates by giving an enhancement by almost 7 orders of magnitude compared to conventional Raman spectroscopy. Several factors that affect the photochemical reduction to form the AuNPs were examined. It is found that the concentration of gold ion, UV irradiation time, and citrate concentration have more impact on the reaction rate than on the morphologies of the AuNPs. The gold-decorated magnetic microspheres are highly stable in aqueous solution and capable of concentrating nucleobases. A linear response of the SERS signal to adenine in concentrations up to 10 μM is found, with a linear regression coefficient of 0.997. The detection limit is estimated to a few hundreds of nM (at an SNR of 3). Based on its specific Raman peak at 734 cm−1, adenine can be selectively determined without interference by other nucleobases, and a recovery higher than 95 % could be obtained. (author)

  15. Multiple Decay Mechanisms and 2D-UV Spectroscopic Fingerprints of Singlet Excited Solvated Adenine-Uracil Monophosphate.

    Science.gov (United States)

    Li, Quansong; Giussani, Angelo; Segarra-Martí, Javier; Nenov, Artur; Rivalta, Ivan; Voityuk, Alexander A; Mukamel, Shaul; Roca-Sanjuán, Daniel; Garavelli, Marco; Blancafort, Lluís

    2016-05-23

    The decay channels of singlet excited adenine uracil monophosphate (ApU) in water are studied with CASPT2//CASSCF:MM potential energy calculations and simulation of the 2D-UV spectroscopic fingerprints with the aim of elucidating the role of the different electronic states of the stacked conformer in the excited state dynamics. The adenine (1) La state can decay without a barrier to a conical intersection with the ground state. In contrast, the adenine (1) Lb and uracil S(U) states have minima that are separated from the intersections by sizeable barriers. Depending on the backbone conformation, the CT state can undergo inter-base hydrogen transfer and decay to the ground state through a conical intersection, or it can yield a long-lived minimum stabilized by a hydrogen bond between the two ribose rings. This suggests that the (1) Lb , S(U) and CT states of the stacked conformer may all contribute to the experimental lifetimes of 18 and 240 ps. We have also simulated the time evolution of the 2D-UV spectra and provide the specific fingerprint of each species in a recommended probe window between 25 000 and 38 000 cm(-1) in which decongested, clearly distinguishable spectra can be obtained. This is expected to allow the mechanistic scenarios to be discerned in the near future with the help of the corresponding experiments. Our results reveal the complexity of the photophysics of the relatively small ApU system, and the potential of 2D-UV spectroscopy to disentangle the photophysics of multichromophoric systems.

  16. Reactivity of nitrogen atoms in adenine and (Ade)2Cu complexes towards ribose and 2-furanmethanol: Formation of adenosine and kinetin.

    Science.gov (United States)

    Nashalian, Ossanna; Yaylayan, Varoujan A

    2017-01-15

    To explore the interaction of nucleosides and nucleobases in the context of the Maillard reaction and to identify the selectivity of purine nitrogen atoms towards various electrophiles, model systems composed of adenine or adenosine, glycine, ribose and/or 2-furanmethanol (with and without copper) were studied in aqueous solutions heated at 110°C for 2h and subsequently analyzed by ESI/qTOF/MS/MS in addition to isotope labelling techniques. The results indicated that ribose selectively formed mono-ribosylated N(6) adenine, but in the presence of (Ade)2Cu complex the reaction mixture generated mono-, di- and tri-substituted sugar complexes and their hydrolysis products of mono-ribosylated N(6) and N(9) adenine adducts and di-ribosylated N(6,9) adenine. Furthermore, the reaction of 2-furanmethanol with adenine in the presence of ribose generated kinetin and its isomer, while its reaction with adenosine generated kinetin riboside, as confirmed by comparing the MS/MS profiles of these adducts to those of commercial standards. PMID:27542499

  17. Characterization of a DNA Adenine Methyltransferase Gene of Borrelia hermsii and Its Dispensability for Murine Infection and Persistence

    Science.gov (United States)

    James, Allison E.; Rogovskyy, Artem S.; Crowley, Michael A.; Bankhead, Troy

    2016-01-01

    DNA methyltransferases have been implicated in the regulation of virulence genes in a number of pathogens. Relapsing fever Borrelia species harbor a conserved, putative DNA methyltransferase gene on their chromosome, while no such ortholog can be found in the annotated genome of the Lyme disease agent, Borrelia burgdorferi. In the relapsing fever species Borrelia hermsii, the locus bh0463A encodes this putative DNA adenine methyltransferase (dam). To verify the function of the BH0463A protein product as a Dam, the gene was cloned into a Dam-deficient strain of Escherichia coli. Restriction fragment analysis subsequently demonstrated that complementation of this E. coli mutant with bh0463A restored adenine methylation, verifying bh0463A as a Dam. The requirement of bh0463A for B. hermsii viability, infectivity, and persistence was then investigated by genetically disrupting the gene. The dam- mutant was capable of infecting immunocompetent mice, and the mean level of spirochetemia in immunocompetent mice was not significantly different from wild type B. hermsii. Collectively, the data indicate that dam is dispensable for B. hermsii viability, infectivity, and persistence. PMID:27195796

  18. Evaluation of Porin Interaction with Adenine Nucleotide Translocase and Cyclophilin-D Proteins after Brain Ischemia and Reperfusion

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Atlasi

    2011-01-01

    Full Text Available Objective (s Porin is a mitochondrial outer membrane channel, which usually functions as the pathway for the movement of various substances in and out of the mitochondria and is considered to be a component of the permeability transition (PT pore complex that plays a role in the PT. We addressed the hypothesis that porin interacts with other mitochondrial proteins after ischemic injury.Materials and MethodsFor this purpose, we used in vivo 4-vessel occlusion model of rat brain and porin purification method by hydroxyapatite column. After SDS gel electrophoresis and silver nitrate staining, Western blotting was done for porin, adenine nucleotide translocase and cyclophilin-D proteins.Results Porin was purified from mitochondrial mixture in ischemic brain and control groups. Investigation of interaction of adenine nucleotide transposes (ANT and cyclophilin-D with porin by Western blotting showed no proteins co-purified with porin from injured tissues.Conclusion The present study implies that there may not be interaction between porin, and ANT or cyclophilin-D, and if there is any, it is not maintained during the purification procedure.

  19. Targeted disruption of the mouse adenine phosphoribosyltransferase (aprt) gene and the production of APRT-deficient mice

    Energy Technology Data Exchange (ETDEWEB)

    Engle, S.J.; Chen, J.; Tischfield, J.A. [Indiana Univ., School of Medicine, Indianapolis, IN (United States)] [and others

    1994-09-01

    Adenine phosphoribosyltransferase (APRT: EC 2.4.2.7), a ubiquitously expressed purine salvage enzyme, catalyzes the synthesis of AMP and inorganic pyrophosphate from existing adenine and 5-phosphoribosyl-1-pyrophosphate. Deficiency of this enzyme in humans results in the accumulation of 2,8-dihydroxyadenine leading to crystalluria and nephrolithiasis. In order to facilitate our study of this rare, autosomal recessive disorder, we applied the advances in gene targeting technology and mouse embryonic stem (ES) cell culture to the production of APRT-deficient mice. A positive-negative targeting strategy was used. The tageting vector contain 5.6 kb of the mouse APRT gene, a neomycin resistance gene in exon 3 as a positive selection marker, and a HSV thymidine kinase gene at the 3{prime} end of the homology as a negative selection marker. The vector was introduced into D3 ES cells by electroporation and the cells were selected for G418 and ganciclovir (GANC) resistance. G418-GANC resistant clones were screened by Southern blot. One of several correctly targeted clones was expanded and used for blastocyst microinjection to produce chimeric mice. Chimeric animals were bred and agouti progeny heterozygous for the targeted allele were obtained. Heterozygous animals have been bred to produce APRT-deficient animals. Matings are currently underway to determine the phenotype of APRT/HPRT-deficient animals.

  20. Kinetic and thermodynamic study of the reaction catalyzed by glucose-6-phosphate dehydrogenase with nicotinamide adenine dinucleotide

    Energy Technology Data Exchange (ETDEWEB)

    Martin del Campo, Julia S. [Departamento de Fisica Aplicada, Centro de Investigacion y de Estudios Avanzados - Unidad Merida, Carretera antigua a Progreso Km. 6, A.P. 73 Cordemex, 97310, Merida, Yucatan (Mexico); Patino, Rodrigo, E-mail: rtarkus@mda.cinvestav.mx [Departamento de Fisica Aplicada, Centro de Investigacion y de Estudios Avanzados - Unidad Merida, Carretera antigua a Progreso Km. 6, A.P. 73 Cordemex, 97310, Merida, Yucatan (Mexico)

    2011-04-20

    Research highlights: {yields} The reaction catalyzed by one enzyme of the pentose phosphate pathway was studied. {yields} A spectrophotometric method is proposed for kinetic and thermodynamic analysis. {yields} The pH and the temperature influences are reported on physical chemical properties. {yields} Relative concentrations of substrates are also important in the catalytic process. - Abstract: The enzyme glucose-6-phosphate dehydrogenase (G6PD, EC 1.1.1.49) from Leuconostoc mesenteroides has a dual coenzyme specificity with oxidized nicotinamide adenine dinucleotide (NAD{sub ox}) and oxidized nicotinamide adenine dinucleotide phosphate as electron acceptors. The G6PD coenzyme selection is determined by the metabolic cellular prevailing conditions. In this study a kinetic and thermodynamic analysis is presented for the reaction catalyzed by G6PD from L. mesenteroides with NAD{sub ox} as coenzyme in phosphate buffer. For this work, an in situ spectrophotometric technique was employed based on the detection of one product of the reaction. Substrate and coenzyme concentrations as well as temperature and pH effects were evaluated. The apparent equilibrium constant, the Michaelis constant, and the turnover number were determined as a function of each experimental condition. The standard transformed Gibbs energy of reaction was determined from equilibrium constants at different initial conditions. For the product 6-phospho-D-glucono-1,5-lactone, a value of the standard Gibbs energy of formation is proposed, {Delta}{sub f}G{sup o} = -1784 {+-} 5 kJ mol{sup -1}.

  1. A weak pulsed magnetic field affects adenine nucleotide oscillations, and related parameters in aggregating Dictyostelium discoideum amoebae.

    Science.gov (United States)

    Davies, E; Olliff, C; Wright, I; Woodward, A; Kell, D

    1999-02-01

    A model eukaryotic cell system was used to explore the effect of a weak pulsed magnetic field (PMF) on time-varying physiological parameters. Dictyostelium discoideum cells (V12 strain) were exposed to a pulsed magnetic field (PMF) of flux density 0.4 mT, generated via air-cored coils in trains of 2 ms pulses gated at 20 ms. This signal is similar to those used to treat non-uniting fractures. Samples were taken over periods of 20 min from harvested suspensions of amoebae during early aggregation phase, extracted and derivatised for HPLC fluorescent assay of adenine nucleotides. Analysis of variance showed a significant athermal damping effect (P < 0.002, n = 22) of the PMF on natural adenine nucleotide oscillations and some consistent changes in phase relationships. The technique of nonlinear dielectric spectroscopy (NLDS) revealed a distinctive effect of PMF, caffeine and EGTA in modulating the cellular harmonic response to an applied weak signal. Light scattering studies also showed altered frequency response of cells to PMF, EGTA and caffeine. PMF caused a significant reduction of caffeine induced cell contraction (P < 0.0006, n = 19 by paired t-test) as shown by Malvern particle size analyser, suggesting that intracellular calcium may be involved in mediating the effect of the PMF. PMID:10228582

  2. Molecular cloning and characterization of the gene encoding the adenine methyltransferase M.CviRI from Chlorella virus XZ-6E.

    OpenAIRE

    Stefan, C; Xia, Y N; Van Etten, J L

    1991-01-01

    The gene encoding the DNA methyltransferase M.CviRI from Chlorella virus XZ-6E was cloned and expressed in Escherichia coli. M.CviRI methylates adenine in TGCA sequences. DNA containing the M.CviRI gene was sequenced and a single open reading frame of 1137 bp was identified which could code for a polypeptide of 379 amino acids with a predicted molecular weight of 42,814. Comparison of the M.CviRI predicted amino acid sequence with another Chlorella virus and 14 bacterial adenine methyltransfe...

  3. Kinetics and thermodynamics of the reaction between the •OH radical and adenine – a theoretical investigation

    DEFF Research Database (Denmark)

    Milhøj, Birgitte Olai; Sauer, Stephan P. A.

    2015-01-01

    The accessibility of all possible reaction paths for the reaction between the nucleobase adenine and the •OH radical is investigated through quantum chemical calculations of barrier heights and rate constants at the wB97X-D/6-311++G(2df,2pd) level with Eckart tunneling corrections. First the...... Pople and Dunning basis sets, all of which have been employed in similar investigations in the literature. Improved energies are obtained through single point calculations with CCSD(T) and the same basis sets, and reaction rate constants are calculated for all methods both without tunneling corrections...... and with the Wigner, Bell and Eckart corrections. Compared to CCSD(T)//BHandHLYP/aug-cc-pVTZ reference results, the wB97XD/6-311++G(2df,2pd) method combined with Eckart tunneling corrections provides a sensible compromise between accuracy and time. Using this method all sub-reactions of the reaction...

  4. Nitric oxide interacts with oxygen free radicals to evoke the release of adenosine and adenine nucleotides from rat hippocampal slices.

    Science.gov (United States)

    Broad, R M; Fallahi, N; Fredholm, B B

    2000-07-01

    The present study examined some possible mechanisms underlying the previously demonstrated release of adenosine by nitric oxide (NO) donors. Perfusion with the NO-donor S-nitroso-N-acetyl penicillamine (SNAP; 300 microM) led to a significant increase in the release of [3H]purines from both unstimulated and electrically stimulated hippocampal slices prelabeled with [3H]adenine. The NO-donor also evoked the release of endogenous ATP and ADP from unstimulated slices and, when combined with electrical stimulation, the release of ATP, AMP and adenosine. The SNAP-induced [3H]purine release was calcium-dependent, but not affected by the glutamate receptor antagonists MK-801 ((+)-5-methyl-10,11-dihydro-5H-dibenzo[a, d]-cyclohepten-5,10-imine;100 nM) and CNQX (6-cyano-7-nitroquinoxaline-2,3-dione; 10 microM). Zaprinast (5 microM), an inhibitor of the cyclic GMP-dependent phosphodiesterase and 8-Br-cyclic GMP (0.01-1 mM) failed to evoke the release of purines, whereas generation of oxygen free radicals by xanthine plus xanthine oxidase did evoke purine release. Coperfusion of SNAP with the free radical scavengers superoxide dismutase (SOD; 60 microg/ml) and catalase (50 microg/ml) reduced or eliminated the ability of the NO-donor to enhance [3H]purine release, but the poly (ADP-ribosyl) synthetase (PARS) inhibitor benzamide (500 microM) did not affect it. These data indicate that NO interacts with superoxide, likely forming peroxynitrite, which subsequently acts to release adenosine and adenine nucleotides from hippocampal tissue.

  5. A concise and simple synthesis of 1-hydroxy-phenethylamine derivatives: Formal synthesis of naturally occurring norephedrine, virolin and 3-hydroxy-2-phosphonylmethoxypropyl adenine

    Indian Academy of Sciences (India)

    S Saha; P Chakraborty; S C Roy

    2014-05-01

    A concise and simple synthesis of 1-hydroxy-phenethylamine derivatives has been achieved following classical organic transformations using commercially available chiral pools. The said derivatives were explored for the synthesis of naturally occurring bio-active small molecules. Formal synthesis of norephedrine, virolin and 3-hydroxy-2-phosphonylmethoxypropyl adenine has been demonstrated.

  6. Effects of low-molecular-weight-chitosan on the adenine-induced chronic renal failure rats in vitro and in vivo

    Science.gov (United States)

    Zhi, Xuan; Han, Baoqin; Sui, Xianxian; Hu, Rui; Liu, Wanshun

    2015-02-01

    The effects of low-molecular-weight-chitosan (LMWC) on chronic renal failure (CRF) rats induced by adenine were investigated in vivo and in vitro. Chitosan were hydrolyzed using chitosanase at pH 6-7 and 37° for 24 h to obtain LMWC. In vitro, the effect of LMWC on the proliferation of renal tubular epithelial cells (RTEC) showed that it had no cytotoxic effect and could promote cell growth. For the in vivo experiment, chronic renal failure rats induced by adenine were randomly divided into control group, Niaoduqing group, and high-, medium- and low-dose LMWC groups. For each group, we detected serum creatinine (SCR), blood urea nitrogen (BUN), and total superoxide dismutase (T-SOD), glutathione oxidase (GSH-Px) activities of renal tissue, and obtained the ratio of kidney weight/body weight, pathological changes of kidney. The levels of serum SCR, BUN were higher in the adenine-induced rats than those in the control group, indicating that the rat chronic renal failure model worked successfully. The results after treatment showed that LMWC could reduce the SCR and BUN levels and enhance the activities/levels of T-SOD and GSH-PX in kidney compared to control group. Histopathological examination revealed that adenine-induced renal alterations were restored by LMWC at three tested dosages, especially at the low dosage of 100 mg kg-1 d-1.

  7. Modular kinetic analysis of the adenine nucleotide translocator-mediated effects of palmitoyl-CoA on the oxidative phosphorylation in isolated rat liver mitochondria

    NARCIS (Netherlands)

    Ciapaite, J; Van Eikenhorst, G; Bakker, SJL; Diamant, M; Heine, RJ; Wagner, MJ; Westerhoff, HV; Krab, K

    2005-01-01

    To test whether long-chain fatty acyl-CoA esters link obesity with type 2 diabetes through inhibition of the mitochondrial adenine nucleotide translocator, we applied a system-biology approach, dual modular kinetic analysis, with mitochondrial membrane potential (Delta psi) and the fraction of matri

  8. Persistent changes in the initial rate of pyruvate transport by isolated rat liver mitochondria after preincubation with adenine nucleotides and calcium ions

    NARCIS (Netherlands)

    Vaartjes, W.J.; Breejen, J.N. den; Geelen, M.J.H.; Bergh, S.G. van den

    1980-01-01

    1. Preincubation of isolated rat-liver mitochondria in the presence of adenine nucleotides or Ca2+ results in definite and persistent changes in the initial rate of pyruvate transport. 2. These changes in the rate of pyruvate transport are accompanied by equally persistent changes in the opposite d

  9. Metabolic control of mitochondrial properties by adenine nucleotide translocator determines palmitoyl-CoA effects - Implications for a mechanism linking obesity and type 2 diabetes

    NARCIS (Netherlands)

    Ciapaite, Jolita; Bakker, Stephan J. L.; Diamant, Michaela; van Eikenhorst, Gerco; Heine, Robert J.; Westerhoff, Hans V.; Krab, Klaas

    2006-01-01

    Inhibition of the mitochondrial adenine nucleotide translocator (ANT) by long-chain acyl-CoA esters has been proposed to contribute to cellular dysfunction in obesity and type 2 diabetes by increasing formation of reactive oxygen species and adenosine via effects on the coenzyme Q redox state, mitoc

  10. Effects of the Chinese Herbal Medicine Based on Hachimi-jio-gan in Male Rats with the Adenine-Induced Osteopenia

    Institute of Scientific and Technical Information of China (English)

    Takeshi Ogirima; Kaori Tano; Masayuki Kanehara; Ming Gao; Xiuyun Wang; Yi Guo; Yanjun Zhang; Liping Guo; Torao Ishida

    2005-01-01

    In the adenine-induced renal failure rats, reversibility of renal failure and recovery of bone mineral density (BMD) by discontinuation of adenine-rich diet were reported: We think that the effect to bone metabolism with medication may be able to be evaluated as reinforcement of the BMD recovery. We have so far investigated the Chinese herbal medicine based on Hachimi-jio-gan (HJG) which are more effective than HJG alone. In this study, we investigated the effects of our Chinese herbal prescription on BMD in the adenine-treated rats compared to that of vitamin D3treatment. Young male rats were administrated 100 mg/ml adenine for 8 weeks, and they showed renal failure and bone loss. The adenine-treated rats were divided into the following 3 groups, that is, the group experienced no treatment (control), the group givenour Chinese herbal medicine (HAO), and the group given vitamin D3 (VD3) medication. It is likely that VD3 medication was less effective for increase of the femoral BMD than increase of the spinal BMD. In contrast, HAO was effective for increase of the femoral BMD. The VD3 group showed low deoxypyridinoline (Dpd: bone resorption maker) as compared to the control group.However, the HAO group showed same or slightly high Dpd. It is suggested that VD3 may increase BMD by reduction of bone resorption, while HAO may show effect on BMD by activating bone metabolism. It is indicated that HAO may become a curative medicine for bone loss because of the different target site from vitamin D3.

  11. Recognition and repair of the CC-1065-(N3-Adenine)-DNA adduct by the UVRABC nuclease

    Energy Technology Data Exchange (ETDEWEB)

    Tang, M.; Lee, C.S.; Doisy, R.; Ross, L.; Needham-VanDevanter, D.R.; Hurley, L.H.

    1988-02-09

    The recognition and repair of the helix-stabilizing and relatively nondistortive CC-1065-(N3-adenine)-DNA adduct by UVRABC nuclease has been investigated both in vivo with phi X174RFI DNA by a transfection assay and in vitro by a site-directed adduct in a 117 base pair fragment from M13mp1. CC-1065 is a potent antitumor antibiotic produced by Streptomyces zelensis which binds within the minor groove of DNA through N3 of adenine. In contrast to the helix-destabilizing and distortive modifications of DNA caused by ultraviolet light or N-acetoxy-2-(acetylamino)fluorene, CC-1065 increases the melting point of DNA and decreases the S1 nuclease activity. Using a viral DNA-Escherichia coli transfection system, the authors have found that the uvrA, uvrB, and uvrC genes, which code for the major excision repair proteins for UV- and NAAAF-induced DNA damage, are also involved in the repair of CC-1065-DNA adducts. In contrast, the uvrD gene product, which has been found to be involved in the repair of UV damage, has no effect in repairing CC-1065-DNA adducts. Purified UVRA, UVRB, and UVRC proteins must work in concert to incise the drug-modified phi X174RFI DNA. Using a site-directed and multiple CC-1065 modified (MspI-BstNI) 117 base pair fragment from M13mp1, they have found that UVRABC nuclease incises at the eight phosphodiester bond on the 5' side of the CC-1065-DNA adduct on the drug-modified strand. The enzymes do not cut the noncovalently modified strand. The DNA sequence and/or helix-stabilizing effect of multiple adducts may determine the recognition and/or incision of the drug-DNA adduct by UVRABC nuclease. These results are discussed in relation to the structure of the CC-1065-DNA adduct and the effect of drug binding on local DNA structure.

  12. Recognition and repair of the CC-1065-(N3-Adenine)-DNA adduct by the UVRABC nuclease

    International Nuclear Information System (INIS)

    The recognition and repair of the helix-stabilizing and relatively nondistortive CC-1065-(N3-adenine)-DNA adduct by UVRABC nuclease has been investigated both in vivo with phi X174RFI DNA by a transfection assay and in vitro by a site-directed adduct in a 117 base pair fragment from M13mp1. CC-1065 is a potent antitumor antibiotic produced by Streptomyces zelensis which binds within the minor groove of DNA through N3 of adenine. In contrast to the helix-destabilizing and distortive modifications of DNA caused by ultraviolet light or N-acetoxy-2-(acetylamino)fluorene, CC-1065 increases the melting point of DNA and decreases the S1 nuclease activity. Using a viral DNA-Escherichia coli transfection system, the authors have found that the uvrA, uvrB, and uvrC genes, which code for the major excision repair proteins for UV- and NAAAF-induced DNA damage, are also involved in the repair of CC-1065-DNA adducts. In contrast, the uvrD gene product, which has been found to be involved in the repair of UV damage, has no effect in repairing CC-1065-DNA adducts. Purified UVRA, UVRB, and UVRC proteins must work in concert to incise the drug-modified phi X174RFI DNA. Using a site-directed and multiple CC-1065 modified (MspI-BstNI) 117 base pair fragment from M13mp1, they have found that UVRABC nuclease incises at the eight phosphodiester bond on the 5' side of the CC-1065-DNA adduct on the drug-modified strand. The enzymes do not cut the noncovalently modified strand. The DNA sequence and/or helix-stabilizing effect of multiple adducts may determine the recognition and/or incision of the drug-DNA adduct by UVRABC nuclease. These results are discussed in relation to the structure of the CC-1065-DNA adduct and the effect of drug binding on local DNA structure

  13. Amidate prodrugs of 9-[2-(phosphonomethoxy)ethyl]adenine as inhibitors of adenylate cyclase toxin from Bordetella pertussis.

    Science.gov (United States)

    Šmídková, Markéta; Dvoráková, Alexandra; Tloust'ová, Eva; Česnek, Michal; Janeba, Zlatko; Mertlíková-Kaiserová, Helena

    2014-01-01

    Adenylate cyclase toxin (ACT) is the key virulence factor of Bordetella pertussis that facilitates its invasion into the mammalian body. 9-[2-(Phosphonomethoxy)ethyl]adenine diphosphate (PMEApp), the active metabolite of the antiviral drug bis(POM)PMEA (adefovir dipivoxil), has been shown to inhibit ACT. The objective of this study was to evaluate six novel amidate prodrugs of PMEA, both phenyloxy phosphonamidates and phosphonodiamidates, for their ability to inhibit ACT activity in the J774A.1 macrophage cell line. The two phenyloxy phosphonamidate prodrugs exhibited greater inhibitory activity (50% inhibitory concentration [IC50] = 22 and 46 nM) than the phosphonodiamidates (IC50 = 84 to 3,960 nM). The inhibitory activity of the prodrugs correlated with their lipophilicity and the degree of their hydrolysis into free PMEA in J774A.1 cells. Although the prodrugs did not inhibit ACT as effectively as bis(POM)PMEA (IC50 = 6 nM), they were significantly less cytotoxic. Moreover, they all reduced apoptotic effects of ACT and prevented an ACT-induced elevation of intracellular [Ca(2+)]i. The amidate prodrugs were less susceptible to degradation in Caco-2 cells compared to bis(POM)PMEA, while they exerted good transepithelial permeability in this assay. As a consequence, a large amount of intact amidate prodrug is expected to be available to target macrophages in vivo. This feature makes nontoxic amidate prodrugs attractive candidates for further investigation as novel antimicrobial agents.

  14. Continuing Exposure to Low-Dose Nonylphenol Aggravates Adenine-Induced Chronic Renal Dysfunction and Role of Rosuvastatin Therapy

    Directory of Open Access Journals (Sweden)

    Yen Chia-Hung

    2012-07-01

    Full Text Available Abstract Background Nonylphenol (NP, an environmental organic compound, has been demonstrated to enhance reactive-oxygen species (ROS synthesis. Chronic exposure to low-dose adenine (AD has been reported to induce chronic kidney disease (CKD. Methods In this study, we tested the hypothesis that chronic exposure to NP will aggravate AD-induced CKD through increasing generations of inflammation, ROS, and apoptosis that could be attenuated by rosuvastatin. Fifty male Wistar rats were equally divided into group 1 (control, group 2 (AD in fodder at a concentration of 0.25%, group 3 (NP: 2 mg/kg/day, group 4 (combined AD & NP, and group 5 (AD-NP + rosuvastatin: 20 mg/kg/day. Treatment was continued for 24 weeks for all animals before being sacrificed. Results By the end of 24 weeks, serum blood urea nitrogen (BUN and creatinine levels were increased in group 4 than in groups 1–3, but significantly reduced in group 5 as compared with group 4 (all p  Conclusion NP worsened AD-induced CKD that could be reversed by rosuvastatin therapy.

  15. Over-expression of Adenine Nucleotide Translocase 1 (ANT1) Induces Apoptosis and Tumor Regression in vivo

    International Nuclear Information System (INIS)

    Adenine nucleotide translocase (ANT) is located in the inner mitochondrial membrane and catalyzes the exchange of mitochondrial ATP for cytosolic ADP. ANT has been known to be a major component of the permeability transition pore complex of mitochondria and contributes to mitochondria-mediated apoptosis. Human ANT has four isoforms (ANT1, ANT2, ANT3, and ANT4), and the expression of the ANT isoforms is variable depending on the tissue and cell type, developmental stage, and proliferation status. Among the isoforms, ANT1 is highly expressed in terminally-differentiated tissues, but expressed in low levels in proliferating cells, such as cancer cells. In particular, over-expression of ANT1 induces apoptosis in cultured tumor cells. We applied an ANT1 gene transfer approach to induce apoptosis and to evaluate the anti-tumor effect of ANT1 in a nude mouse model. We demonstrated that ANT1 transfection induced apoptosis of MDA-MB-231 cells, inactivated NF-κB activity, and increased Bax expression. ANT1-inducing apoptosis was accompanied by the disruption of mitochondrial membrane potential, cytochrome c release and the activation of caspases-9 and -3. Moreover, ANT1 transfection significantly suppressed tumor growth in vivo. Our results suggest that ANT1 transfection may be a useful therapeutic modality for the treatment of cancer

  16. Silver nanoparticles coated with adenine: preparation, self-assembly and application in surface-enhanced Raman scattering

    International Nuclear Information System (INIS)

    We describe herein the preparation of silver nanoparticles (AgNPs) using nucleobase adenine as protecting agent through the in situ chemical reduction of AgNO3 with NaBH4 in an aqueous medium at room temperature. As-prepared AgNPs were characterized by UV-visible spectra, transmission electron microscopy and x-ray photoelectron spectroscopy. All these data confirmed the formation of AgNPs. On the basis of electrostatic interactions between as-prepared AgNPs and anionic polyelectrolyte poly(sodium 4-styrenesulfonate) (PSS), we successfully fabricated (PSS/AgNP)n (n = 0-9) multilayers on a 3-mercaptopropyltrimethoxysilane/AgNP functionalized indium tin oxide (ITO) substrate via the layer-by-layer self-assembly technique and characterized as-formed multilayers with UV-visible spectra. Furthermore, these ITO substrates coated with multilayers of different thickness were investigated as surface-enhanced Raman scattering (SERS)-active substrates using p-aminothiophenol as a probe molecule, implying that these multilayers substrates may be promising for a new type of SERS-active substrate

  17. Drought-Stimulated Activity of Plasma Membrane Nicotinamide Adenine Dinucleotide Phosphate Oxidase and Its Catalytic Properties in Rice

    Institute of Scientific and Technical Information of China (English)

    Zhuang-Qin Duan; Lei Bai; Zhi-Guang Zhao; Guo-Ping Zhang; Fang-Min Cheng; Li-Xi Jiang; Kun-Ming Chen

    2009-01-01

    The activity of plasma membrane (PM) nicoUnamide adenine dinucleotide phosphate (NADPH) oxidase and Its catalytic properties in rice was investigated under drought stress conditions. Drought stress led to decreased leaf relative water content (RWC) and, as a result of drought-induced oxidative stress, the activities of antioxidant enzymes increased significantly. More interestingly, the intensity of applied water stress was correlated with increased production of H_2O_2and O_2~- and elevated activity of PM NADPH oxidase, a key enzyme of reactive oxygen species generation in plants.Histochemlcal analyses also revealed increased H_2O_2 and O_2~- production in drought-stressed leaves. Application of dlphenylene iodonium (DPI), an Inhibitor of PM NADPH oxidasa, did not alleviate drought-induced production of H_2O_2 and O_2~-. Catalysis experiments indicated that the dce PM NADPH oxidass was partially fiavin-dependent. The pH and temperature optima for this enzyme were 9.8 and 40 ℃, respectively. In addition, drought stress enhanced the activity under alkaline pH and high temperature conditions. These results suggest that a complex regulatory mechanism, associated with the NADPH oxidase-H_2O_2 system, is involved in the response of rice to drought stress.

  18. Study of the chemical evolution and spectral signatures of some interstellar precursor molecules of adenine, glycine alanine

    CERN Document Server

    Majumdar, Liton; Chakrabarti, Sandip K; Chakrabarti, Sonali; 10.1016/j.newast.2012.09.002

    2012-01-01

    We carry out a quantum chemical calculation to obtain the infrared and electronic absorption spectra of several complex molecules of the interstellar medium (ISM). These molecules are the precursors of adenine, glycine & alanine. They could be produced in the gas phase as well as in the ice phase. We carried out a hydro-chemical simulation to predict the abundances of these species in the gas as well as in the ice phase. Gas and grains are assumed to be interacting through the accretion of various species from the gas phase on to the grain surface and desorption (thermal evaporation and photo-evaporation) from the grain surface to the gas phase. Depending on the physical properties of the cloud, the calculated abundances varies. The influence of ice on vibrational frequencies of different pre-biotic molecules was obtained using Polarizable Continuum Model (PCM) model with the integral equation formalism variant (IEFPCM) as default SCRF method with a dielectric constant of 78.5. Time dependent density func...

  19. Theoretical Investigation on the Substituent Effect of Halogen Atoms at the C8 Position of Adenine: Relative Stability, Vibrational Frequencies, and Raman Spectra of Tautomers.

    Science.gov (United States)

    Chen, Yan-Li; Wu, De-Yin; Tian, Zhong-Qun

    2016-06-16

    We have theoretically investigated the substituent effect of adenine at the C8 position with a substituent X = H, F, Cl, and Br by using the density functional theory (DFT) at the B3LYP/6-311+G(d, p) level. The aim is to study the substituent effect of halogen atoms on the relative stability, vibrational frequencies, and solvation effect of tautomers. Our calculated results show that for substituted adenine molecules the N9H8X tautomer to be the most stable structure in gas phase at the present theoretical level. Here N9H8X denotes the hydrogen atom binds to the N9 position of imidazole ring and X denotes H, F, Cl, and Br atoms. The influence of the induced attraction of the fluorine substituent is significantly larger than chlorine and bromine ones. The halogen substituent effect has a significant influence on changes of vibrational frequencies and Raman intensities.

  20. Deficiency of the iron-sulfur clusters of mitochondrial reduced nicotinamide-adenine dinucleotide-ubiquinone oxidoreductase (complex I) in an infant with congenital lactic acidosis.

    OpenAIRE

    Moreadith, R W; Batshaw, M L; Ohnishi, T.; Kerr, D.; Knox, B; Jackson, D; Hruban, R; Olson, J; Reynafarje, B; Lehninger, A L

    1984-01-01

    We report the case of an infant with hypoglycemia, progressive lactic acidosis, an increased serum lactate/pyruvate ratio, and elevated plasma alanine, who had a moderate to profound decrease in the ability of mitochondria from four organs to oxidize pyruvate, malate plus glutamate, citrate, and other NAD+-linked respiratory substrates. The capacity to oxidize the flavin adenine dinucleotide-linked substrate, succinate, was normal. The most pronounced deficiency was in skeletal muscle, the le...

  1. Can an excess electron localize on a purine moiety in the adenine-thymine Watson-Crick base pair? A computational study

    Science.gov (United States)

    Mazurkiewicz, Kamil; Harańczyk, Maciej; Gutowski, Maciej; Rak, Janusz

    The electron affinity and the propensity to electron-induced proton transfer (PT) of hydrogen-bonded complexes between the Watson-Crick adenine-thymine pair (AT) and simple organic acid (HX), attached to adenine in the Hoogsteen-type configuration, were studied at the B3LYP/6-31+G** level. Although the carboxyl group is deprotonated at physiological pH, its neutral form, COOH, resembles the peptide bond or the amide fragment in the side chain of asparagine (Asn) or glutamine (Gln). Thus, these complexes mimic the interaction between the DNA environment (e.g., proteins) and nucleobase pairs incorporated in the biopolymer. Electron attachment is thermodynamically feasible and adiabatic electron affinities range from 0.41 to 1.28 eV, while the vertical detachment energies of the resulting anions span the range of 0.39-2.88 eV. Low-energy activation barriers separate the anionic minima: aHX(AT) from the more stable single-PT anionic geometry, aHX(AT)-SPT, and aHX(AT)-SPT from the double-PT anionic geometry, aHX(AT)-DPT. Interaction between the adenine of the Watson-Crick AT base pair with an acidic proton donor probably counterbalances the larger EA of isolated thymine, as SOMO is almost evenly delocalized over both types of nucleic bases in the aHX(AT) anions. Moreover, as a result of PT the excess electron localizes entirely on adenine. Thus, in DNA interacting with its physiological environment, damage induced by low-energy electrons could begin, contrary to the current view, with the formation of purine anions, which are not formed in isolated DNA because of the greater stability of anionic pyrimidines.0

  2. A comparative cluster analysis of nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase histochemistry in the brains of amphibians.

    Science.gov (United States)

    Pinelli, Claudia; Rastogi, Rakesh K; Scandurra, Anna; Jadhao, Arun G; Aria, Massimo; D'Aniello, Biagio

    2014-09-01

    Nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) is a key enzyme in the synthesis of the gaseous neurotransmitter nitric oxide. We compare the distribution of NADPH-d in the brain of four species of hylid frogs. NADPH-d-positive fibers are present throughout much of the brain, whereas stained cell groups are distributed in well-defined regions. Whereas most brain areas consistently show positive neurons in all species, in some areas species-specific differences occur. We analyzed our data and those available for other amphibian species to build a matrix on NADPH-d brain distribution for a multivariate analysis. Brain dissimilarities were quantified by using the Jaccard index in a hierarchical clustering procedure. The whole brain dendrogram was compared with that of its main subdivisions by applying the Fowlkes-Mallows index for dendrogram similarity, followed by bootstrap replications and a permutation test. Despite the differences in the distribution map of the NADPH-d system among species, cluster analysis of data from the whole brain and hindbrain faithfully reflected the evolutionary history (framework) of amphibians. Dendrograms from the secondary prosencephalon, diencephalon, mesencephalon, and isthmus showed some deviation from the main scheme. Thus, the present analysis supports the major evolutionary stability of the hindbrain. We provide evidence that the NADPH-d system in main brain subdivisions should be cautiously approached for comparative purposes because specific adaptations of a single species could occur and may affect the NADPH-d distribution pattern in a brain subdivision. The minor differences in staining pattern of particular subdivisions apparently do not affect the general patterns of staining across species. PMID:24549578

  3. Induction of ischemic tolerance in rat liver via reduced nicotinamide adenine dinucleotide phosphate oxidase in Kupffer cells

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To elucidate the mechanisms of hepatocyte preconditioning by H2O2 to better understand the pathophysiology of ischemic preconditioning.METHODS: The in vitro effect of H2O2 pretreatment was investigated in rat isolated hepatocytes subjected to anoxia/reoxygenation. Cell viability was assessed with propidium iodide fluorometry. In other experiments, rat livers were excised and subjected to warm ischemia/reperfusion in an isolated perfused liver system to determine leakage of liver enzymes. Preconditioning was performed by H2O2 perfusion, or by stopping the perfusion for 10 min followed by 10 min of reperfusion.To inhibit Kupffer cell function or reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase,gadolinium chloride was injected prior to liver excision, or diphenyleneiodonium, an inhibitor of NADPH oxidase, was added to the perfusate, respectively. Histological detection of o~gen radical formation in Kupffer cells was performed by perfusion with nitro blue tetrazolium.RESULTS: Anoxia/reoxygenation decreased hepatocyte viability compared to the controls. Pretreatment with H2O2 did not improve such hepatocyte injury. In liver perfusion experiments, however, H2O2 preconditioning reduced warm ischemia/reperfusion injury, which was reversed by inhibition of Kupffer cell function or NADPH oxidase. Histological examination revealed that H2O2 preconditioning induced oxygen radical formation in Kupffer cells. NADPH oxidase inhibition also reversed hepatoprotection by ischemic preconditioning.CONCLUSION: H2O2 preconditioning protects hepatocytes against warm ischemia/reperfusion injury via NADPH oxidase in Kupffer cells, and not directly. NADPH oxidase also mediates hepatoprotection by ischemic preconditioning.

  4. Real-time measurements of nicotinamide adenine dinucleotide in live human trabecular meshwork cells: Effects of acute oxidative stress✩

    Science.gov (United States)

    Masihzadeh, Omid; Ammar, David A.; Lei, Tim C.; Gibson, Emily A.; Kahook, Malik Y.

    2016-01-01

    The trabecular meshwork (TM) region of the eye is exposed to a constant low-level of oxidative insult. The cumulative damage may be the reason behind age-dependent risk for developing primary open angle glaucoma. Chronic and acute effects of hydrogen peroxide (H2O2) on TM endothelial cells include changes in viability, protein synthesis, and cellular adhesion. However, little if anything is known about the immediate effect of H2O2 on the biochemistry of the TM cells and the initial response to oxidative stress. In this report, we have used two-photon excitation autofluorescence (2PAF) to monitor changes to TM cell nicotinamide adenine dinucleotide (NADPH). 2PAF allows non-destructive, real-time analysis of concentration of intracellular NADPH. Coupled to reduced glutathione, NADPH, is a major component in the anti-oxidant defense of TM cells. Cultured human TM cells were monitored for over 30 min in control and H2O2-containing solutions. Peroxide caused both a dose- and time-dependent decrease in NADPH signal. NADPH fluorescence in control and in 4 mM H2O2 solutions showed little attenuation of NADPH signal (4% and 9% respectively). TM cell NADPH fluorescence showed a linear decrease with exposure to 20 mM H2O2 (−29%) and 100 mM H2O2 (37%) after a 30 min exposure. Exposure of TM cells to 500 mM H2O2 caused an exponential decrease in NADPH fluorescence to a final attenuation of 46% of starting intensity. Analysis of individual TM cells indicates that cells with higher initial NADPH fluorescence are more refractive to the apparent loss of viability caused by H2O2 than weakly fluorescing TM cells. We conclude that 2PAF of intracellular NADPH is a valuable tool for studying TM cell metabolism in response to oxidative insult. PMID:21354135

  5. Hydration properties of natural and synthetic DNA sequences with methylated adenine or cytosine bases in the R.DpnI target and BDNF promoter studied by molecular dynamics simulations

    Science.gov (United States)

    Shanak, Siba; Helms, Volkhard

    2014-12-01

    Adenine and cytosine methylation are two important epigenetic modifications of DNA sequences at the levels of the genome and transcriptome. To characterize the differential roles of methylating adenine or cytosine with respect to their hydration properties, we performed conventional MD simulations and free energy perturbation calculations for two particular DNA sequences, namely the brain-derived neurotrophic factor (BDNF) promoter and the R.DpnI-bound DNA that are known to undergo methylation of C5-methyl cytosine and N6-methyl adenine, respectively. We found that a single methylated cytosine has a clearly favorable hydration free energy over cytosine since the attached methyl group has a slightly polar character. In contrast, capping the strongly polar N6 of adenine with a methyl group gives a slightly unfavorable contribution to its free energy of solvation. Performing the same demethylation in the context of a DNA double-strand gave quite similar results for the more solvent-accessible cytosine but much more unfavorable results for the rather buried adenine. Interestingly, the same demethylation reactions are far more unfavorable when performed in the context of the opposite (BDNF or R.DpnI target) sequence. This suggests a natural preference for methylation in a specific sequence context. In addition, free energy calculations for demethylating adenine or cytosine in the context of B-DNA vs. Z-DNA suggest that the conformational B-Z transition of DNA transition is rather a property of cytosine methylated sequences but is not preferable for the adenine-methylated sequences investigated here.

  6. Experimental study on the fragmentation of Adenine and Porphyrin molecules induced by low energy multicharged ion impact

    International Nuclear Information System (INIS)

    Since the dissociation of small molecules might play key roles in the understanding of radiation induced damages of living tissues at the primary steps and at the molecular levels, fragmentation dynamics of small biomolecules have drawn much attention. The knowledge of the internal energy is of fundamental importance for understanding its fragmentation dynamics following external excitation. For a long time however, it was difficult to measure this parameter in coincidence with the fragmentation patterns until the development of CIDEC (Collision Induced Dissociation under Energy Control) method in 2007. In this work, the CIDEC method was extended to study the fragmentation of gas-phase biomolecules adenine (Ade: H5C5N5) and porphyrin chloride FeTPPCl (C44H28N4FeCl). The population distribution for each dissociation channel as a function of the excitation energy of the parent molecular ions at a well-determined initial charge state has been experimentally determined, which could shed some light on the fragmentation dynamics of these molecules. In collisions between Cl+ and Ade at 3 keV, the fragmentation pattern of Ade2+ is dominated by the loss of H2CN+ and the successive emission of HCN. The energy distribution of the parent dication confirms the successive emission dynamics. A specific decay channel is observed, i.e. the emission of a charged H2CN+ followed by the emission of HC2N2. The measured mean excitation energies of this channel and other competitive channels are compared. In Kr8+ - FeTPPCl collisions at 80 keV, parent ions FeTPPCL1+,2+,3+ are observed, along with the corresponding decay patterns. It is found that, in the first step the dominant low-energy-cost decay channel is the emission of Cl0 independent of the initial charge state of FeTPPClr+. For the resulted dication FeTPP2+, the dominant fragmentation channel is the neutral evaporation; for the tri-cation however, the dominant fragmentation channel is the asymmetrical fission by emission of a

  7. Catalytic activity of iron hexacyanoosmate(II) towards hydrogen peroxide and nicotinamide adenine dinucleotide and its use in amperometric biosensors

    Energy Technology Data Exchange (ETDEWEB)

    Kotzian, Petr; Janku, Tereza [Department of Analytical Chemistry, University of Pardubice, Nam. Cs. Legii 565, CZ-532 10 Pardubice (Czech Republic); Kalcher, Kurt [Institute of Chemistry - Analytical Chemistry, Karl-Franzens University, Universitaetsplatz 1, A-8010 Graz (Austria); Vytras, Karel [Department of Analytical Chemistry, University of Pardubice, Nam. Cs. Legii 565, CZ-532 10 Pardubice (Czech Republic)], E-mail: karel.vytras@upce.cz

    2007-09-19

    Hydrogen peroxide and nicotinamide adenine dinucleotide (NADH) may be determined amperometrically using screen-printed electrodes chemically modified with iron(III) hexacyanoosmate(II) (Osmium purple) in flow injection analysis (FIA). The determination is based on the exploitation of catalytic currents resulting from the oxidation/reduction of the modifier. The performance of the sensor was characterized and optimized by controlling several operational parameters (applied potential, pH and flow rate of the phosphate buffer). Comparison has been made with analogous complexes of ruthenium (Ruthenium purple) and iron (Prussian blue). Taking into account the sensitivity and stability of corresponding sensors, the best results were obtained with the use of Osmium purple. The sensor exhibited a linear increase of the amperometric signal with the concentration of hydrogen peroxide in the range of 0.1-100 mg L{sup -1} with a detection limit (evaluated as 3{sigma}) of 0.024 mg L{sup -1} with a R.S.D. 1.5% for 10 mg L{sup -1} H{sub 2}O{sub 2} under optimized flow rate of 0.4 mL min{sup -1} in 0.1 M phosphate buffer carrier (pH 6) and a working potential of +0.15 V versus Ag/AgCl. Afterwards, a biological recognition element - either glucose oxidase or ethanol dehydrogenase - was incorporated to achieve a sensor facilitating the determination of glucose or ethanol, respectively. The glucose sensor gave linearity between current and concentration in the range from 1 to 250 mg L{sup -1} with a R.S.D. 2.4% for 100 mg L{sup -1} glucose, detection limit 0.02 mg L{sup -1} (3{sigma}) and retained its original activity after 3 weeks when stored at 6 deg. C. Optimal parameters in the determination of ethanol were selected as: applied potential +0.45 V versus Ag/AgCl, flow rate 0.2 mL min{sup -1} in 0.1 M phosphate buffer carrier (pH 7). Different structural designs of the ethanol sensor were tested and linearity obtained was up to 1000 mg L{sup -1} with a maximum R.S.D. of 5

  8. Adenine phosphoribosyltransferase from Sulfolobus solfataricus is an enzyme with unusual kinetic properties and a crystal structure that suggests it evolved from a 6-oxopurine phosphoribosyltransferase.

    Science.gov (United States)

    Jensen, Kaj Frank; Hansen, Michael Riis; Jensen, Kristine Steen; Christoffersen, Stig; Poulsen, Jens-Christian Navarro; Mølgaard, Anne; Kadziola, Anders

    2015-04-14

    The adenine phosphoribosyltransferase (APRTase) encoded by the open reading frame SSO2342 of Sulfolobus solfataricus P2 was subjected to crystallographic, kinetic, and ligand binding analyses. The enzyme forms dimers in solution and in the crystals, and binds one molecule of the reactants 5-phosphoribosyl-α-1-pyrophosphate (PRPP) and adenine or the product adenosine monophosphate (AMP) or the inhibitor adenosine diphosphate (ADP) in each active site. The individual subunit adopts an overall structure that resembles a 6-oxopurine phosphoribosyltransferase (PRTase) more than known APRTases implying that APRT functionality in Crenarchaeotae has its evolutionary origin in this family of PRTases. Only the N-terminal two-thirds of the polypeptide chain folds as a traditional type I PRTase with a five-stranded β-sheet surrounded by helices. The C-terminal third adopts an unusual three-helix bundle structure that together with the nucleobase-binding loop undergoes a conformational change upon binding of adenine and phosphate resulting in a slight contraction of the active site. The inhibitor ADP binds like the product AMP with both the α- and β-phosphates occupying the 5'-phosphoribosyl binding site. The enzyme shows activity over a wide pH range, and the kinetic and ligand binding properties depend on both pH and the presence/absence of phosphate in the buffers. A slow hydrolysis of PRPP to ribose 5-phosphate and pyrophosphate, catalyzed by the enzyme, may be facilitated by elements in the C-terminal three-helix bundle part of the protein. PMID:25790177

  9. Pleiotropic effects of the yeast Sal1 and Aac2 carriers on mitochondrial function via an activity distinct from adenine nucleotide transport

    Science.gov (United States)

    Kucejova, Blanka; Li, Li; Wang, Xiaowen; Giannattasio, Sergio; Chen, Xin Jie

    2009-01-01

    In Saccharomyces cerevisiae, SAL1 encodes a Ca2+-binding mitochondrial carrier. Disruption of SAL1 is synthetically lethal with the loss of a specific function associated with the Aac2 isoform of the ATP/ADP translocase. This novel activity of Aac2 is defined as the V function (for Viability of aac2 sal1 double mutant), which is independent of the ATP/ADP exchange activity required for respiratory growth (the R function). We found that co-inactivation of SAL1 and AAC2 leads to defects in mitochondrial translation and mitochondrial DNA (mtDNA) maintenance. Additionally, sal1Δ exacerbates the respiratory deficiency and mtDNA instability of ggc1Δ, shy1Δ and mtg1Δ mutants, which are known to reduce mitochondrial protein synthesis or protein complex assembly. The V function is complemented by the human Short Ca2+-binding Mitochondrial Carrier (SCaMC) protein, SCaMC-2, a putative ATP-Mg/Pi exchangers on the inner membrane. However, mitochondria lacking both Sal1p and Aac2p are not depleted of adenine nucleotides. The Aac2R252I and Aac2R253I variants mutated at the R252-254 triplet critical for nucleotide transport retain the V function. Likewise, Sal1p remains functionally active when the R479I and R481I mutations were introduced into the structurally equivalent R479-T480-R481 motif. Finally, we found that the naturally occurring V-R+ Aac1 isoform of adenine nucleotide translocase partially gains the V function at the expense of the R function by introducing the mutations P89L and A96V. Thus, our data support the view that the V function is independent of adenine nucleotide transport associated with Sal1p and Aac2p and this evolutionarily conserved activity affects multiple processes in mitochondria. PMID:18431598

  10. 腺嘌呤-5-溴尿嘧啶复合物中的卤键%Halogen Bonds in Adenine-5-Bromouracil Complexes

    Institute of Scientific and Technical Information of China (English)

    王艳花; 李立; 卢运祥; 邹建卫

    2007-01-01

    Ab initio and density functional calculations were employed to investigate the bonding patterns in the adenine-5-bromouracil(AT+)complexes.It is shown that the Br atom in 5-bromouracil(T+)is involved in bonding both with the hydrogen atom of the amino group of adenine(A)and with N7(A)(or N1(A)).With this motif,the Br atom interacts with a nucleophile(H)in a"head-on"fashion and an electrophile(N)in a"side-on"fashion,forming both hydrogen and halogen bonds.Electrostatic attraction between the Br atom in T+and N7(or N1)of adenine was found via the electrostatic potential analysis.The existence of A bond critical point is identified for the halogen bonds and the topological parameters at the bond critical point indicate the typical closed-shellinteractions in the pairs.Natural bond orbital analysis suggests that the charge transfer from the lone pair of the nitrogen atom of adenine is mainly directed to the C-Br antibonding orbital.Finally,halogen bonds in the T+AT+A tetrads were also explored.%利用从头算和密度泛函理论研究了腺嘌呤(A)-5-溴尿嘧啶复合物中(T+)中的键合模式.研究结果表明,T+中的Br原子同时与A分子中的氨基氢和氮原子存在弱的相互作用,在这种结合模式中,Br原子与亲核基团H正面结合,同时与来电基团N侧面结合,分别形成氢键和卤键.静电势分析发现:T+中的Br原子与A中的N7(或N1)是通过静电相互吸引的.Br与N原子之间的相互作用通过分了中的原子理论得以证实.关键点的拓扑参数显示卤键是闭壳层相互作用.自然键轨道分析说明,A中N原子上孤对电子的电荷主要转移到C-Br的反键轨道.另外在T+AT+A四面体结构中也发现了卤键.

  11. A theoretical and experimental study of the near edge X-ray absorption fine structure (NEXAFS) and X-ray photoelectron spectra (XPS) of nucleobases: Thymine and adenine

    Energy Technology Data Exchange (ETDEWEB)

    Plekan, O. [Sincrotrone Trieste, Area Science Park, I-34012 Basovizza, Trieste (Italy); Feyer, V. [CNR-IMIP, Montelibretti, Rome I-00016 (Italy); Richter, R. [Sincrotrone Trieste, Area Science Park, I-34012 Basovizza, Trieste (Italy); Coreno, M. [CNR-IMIP, Montelibretti, Rome I-00016 (Italy); De Simone, M. [Laboratorio Nazionale TASC, INFM-CNR, 34012 Trieste (Italy); Prince, K.C. [Sincrotrone Trieste, Area Science Park, I-34012 Basovizza, Trieste (Italy); Laboratorio Nazionale TASC, INFM-CNR, 34012 Trieste (Italy); Trofimov, A.B. [Laboratory of Quantum Chemistry, Irkutsk State University, Karl Marx str. 1, 664003 Irkutsk (Russian Federation); Gromov, E.V. [Laboratory of Quantum Chemistry, Irkutsk State University, Karl Marx str. 1, 664003 Irkutsk (Russian Federation); Theoretische Chemie, Physikalisch-Chemisches Institut, Universitaet Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg (Germany); Zaytseva, I.L. [Laboratory of Quantum Chemistry, Irkutsk State University, Karl Marx str. 1, 664003 Irkutsk (Russian Federation); Schirmer, J. [Theoretische Chemie, Physikalisch-Chemisches Institut, Universitaet Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg (Germany)], E-mail: Jochen.Schirmer@pci.uni-heidelberg.de

    2008-05-23

    The core level electron excitation and ionization spectra of thymine and adenine have been investigated by photoabsorption and photoemission spectroscopy, and the results interpreted by means of ab initio calculations using the second-order algebraic-diagrammatic construction (ADC(2)) method for the polarization propagator and the fourth-order ADC method (ADC(4)) for the one-particle Green's function. The photoabsorption spectra are dominated by transitions from core levels to unoccupied {pi} states, but also show clear structures due to Rydberg transitions. The calculated spectra are in good agreement with the experimental results, and many of the observed structures are assigned.

  12. XRD and optical microscopic studies of Co(III) complexes containing 5-cyano-6-(4-pyridyl)-2-thiouracil, thymine and adenine bases

    Indian Academy of Sciences (India)

    Lallan Mishra; Brajesh Pathak; R K Mandal

    2001-06-01

    Multifunctional ligand 5-cyano-6-(-4-pyridyl)-2-thiouracil (L) was prepared and allowed to react with trans [Co(en)2Cl2]+Cl– resulting into [Co(en)2LCl]2+.2Cl– which upon further reaction with equimolar ratio of ligand [L] gave the complex [Co(en)2L2]3+.3Cl–. These metal complexes were then separately reacted with thymine and adenine bases. Complexes thus prepared after characterization by their elemental analysis, FAB mass and spectral (IR, 1HNMR, UV-visible) data were studied for their powder X-ray diffraction and optical microscopic characteristics.

  13. Specific and nonspecific metal ion-nucleotide interactions at aqueous/solid interfaces functionalized with adenine, thymine, guanine, and cytosine oligomers.

    Science.gov (United States)

    Holland, Joseph G; Malin, Jessica N; Jordan, David S; Morales, Esmeralda; Geiger, Franz M

    2011-03-01

    This article reports nonlinear optical measurements that quantify, for the first time directly and without labels, how many Mg(2+) cations are bound to DNA 21-mers covalently linked to fused silica/water interfaces maintained at pH 7 and 10 mM NaCl, and what the thermodynamics are of these interactions. The overall interaction of Mg(2+) with adenine, thymine, guanine, and cytosine is found to involve -10.0 ± 0.3, -11.2 ± 0.3, -14.0 ± 0.4, and -14.9 ± 0.4 kJ/mol, and nonspecific interactions with the phosphate and sugar backbone are found to contribute -21.0 ± 0.6 kJ/mol for each Mg(2+) ion bound. The specific and nonspecific contributions to the interaction energy of Mg(2+) with oligonucleotide single strands is found to be additive, which suggests that within the uncertainty of these surface-specific experiments, the Mg(2+) ions are evenly distributed over the oligomers and not isolated to the most strongly binding nucleobase. The nucleobases adenine and thymine are found to bind only three Mg(2+) ions per 21-mer oligonucleotide, while the bases cytosine and guanine are found to bind eleven Mg(2+) ions per 21-mer oligonucleotide.

  14. Acidity and complex formation studies of 3-(adenine-9-yl)-propionic and 3-(thymine-1-yl)-propionic acids in ethanol-water media

    Science.gov (United States)

    Hammud, Hassan H.; El Shazly, Shawky; Sonji, Ghassan; Sonji, Nada; Bouhadir, Kamal H.

    2015-05-01

    The ligands 3-(adenine-9-yl)propionic acid (AA) and 3-(thymine-1-yl)propionic acid (TA) were prepared by N9-alkylation of adenine and N1-alkylation of thymine with ethylacrylate in presence of a base catalyst, followed by acid hydrolysis of the formed ethyl esters to give the corresponding propionic acid derivatives. The products were characterized by spectral methods (FTIR, 1H NMR and 13C NMR), which confirm their structures. The dissociation constants of ligands, were potentiometrically determined in 0.3 M KCl at 20-50 °C temperature range. The work was extended to study complexation behavior of AA and TA with various biologically important divalent metal ions (Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Mn2+ and Pb2+) in 50% v/v water-ethanol medium at four different temperatures, keeping ionic strength constant (0.3 M KCl). The order of the stability constants of the formed complexes decreases in the sequence Cu2+ > Pb2+ > Zn2+ > Ni2+ > Co2+ > Mn2+ > Cd2+ for both ligands. The effect of temperature was also studied and the corresponding thermodynamic functions (ΔG, ΔH, ΔS) were derived and discussed. The formation of metal complexes has been found to be spontaneous, and the stability constants were dependant markedly on the basicity of the ligands.

  15. Biocomposite based on reduced graphene oxide film modified with phenothiazone and flavin adenine dinucleotide-dependent glucose dehydrogenase for glucose sensing and biofuel cell applications.

    Science.gov (United States)

    Ravenna, Yehonatan; Xia, Lin; Gun, Jenny; Mikhaylov, Alexey A; Medvedev, Alexander G; Lev, Ovadia; Alfonta, Lital

    2015-10-01

    A novel composite material for the encapsulation of redox enzymes was prepared. Reduced graphene oxide film with adsorbed phenothiazone was used as a highly efficient composite for electron transfer between flavin adenine dinucleotide (FAD)-dependent glucose dehydrogenase and electrodes. Measured redox potential for glucose oxidation was lower than 0 V vs Ag/AgCl electrode. The fabricated biosensor showed high sensitivity of 42 mA M(-1) cm(-2), a linear range of glucose detection of 0.5-12 mM, and good reproducibility and stability as well as high selectivity for different interfering compounds. In a semibiofuel cell configuration, the hybrid film generated high power output of 345 μW cm(-2). These results demonstrate a promising potential for this composition in various bioelectronic applications. PMID:26334692

  16. Adenine phosphoribosyltransferase from Sulfolobus solfataricus is an enzyme with unusual kinetic properties and a crystal structure that suggests it evolved from a 6-oxopurine phosphoribosyltransferase

    DEFF Research Database (Denmark)

    Jensen, Kaj Frank; Hansen, Michael Riis; Jensen, Kristine Steen;

    2015-01-01

    The adenine phosphoribosyltransferase (APRTase) encoded by the open reading frame SSO2342 of Sulfolobus solfataricus P2, was subjected to crystallographic, kinetic and ligand binding analyses. The enzyme forms dimers in solution and in the crystals, and binds one molecule of the reactants 5...... evolutionary origin in this family of PRTases. Only the N-terminal two thirds of the polypeptide chain folds as a traditional type I PRTase with a five-stranded β-sheet surrounded by helices. The C-terminal third adopts an unusual three-helix bundle structure that together with the nucleobase-binding loop......H-range and the kinetic and ligand binding properties depend on both pH and the presence/absence of phosphate in the buffers. A slow hydrolysis of PRPP to ribose 5-phosphate and pyrophosphate, catalyzed by the enzyme may be facilitated by elements in the C-terminal three-helix bundle part of the protein....

  17. Reactivities of radicals of adenine and guanine towards reactive oxygen species and reactive nitrogen oxide species: OH rad and NO 2rad

    Science.gov (United States)

    Agnihotri, Neha; Mishra, P. C.

    2011-02-01

    Reactions of radicals of the DNA bases with reactive oxygen species and reactive nitrogen oxide species produce mutagenic products. We have studied reactivities of all the carbon sites of radicals of adenine A(-H) rad and guanine G(-H) rad obtained by removal of H-atoms from their nitrogen sites towards OH rad and NO 2rad . We studied stabilities of A(-H) rad and G(-H) rad and binding energies of their adducts with each of OH rad and NO 2rad using density functional theoretic and MP2 calculations employing the AUG-cc-pVDZ basis set. Solvation in aqueous media was treated using the polarization continuum model. The results obtained explain experimental observations.

  18. Studies on the energy metabolism of opossum (Didelphis virginiana) erythrocytes: V. Utilization of hypoxanthine for the synthesis of adenine and guanine nucleotides in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Bethlenfalvay, N.C.; White, J.C.; Chadwick, E.; Lima, J.E. (Fitzsimons Army Medical Center, Aurora, CO (USA))

    1990-06-01

    High pressure liquid radiochromatography was used to test the ability of opossum erythrocytes to incorporate tracer amounts of (G-{sup 3}H) hypoxanthine (Hy) into ({sup 3}H) labelled triphosphates of adenine and guanine. In the presence of supraphysiologic (30 mM) phosphate which is optimal for PRPP synthesis, both ATP and GTP are extensively labelled. When physiologic (1 mM) medium phosphate is used, red cells incubated under an atmosphere of nitrogen accumulate ({sup 3}H) ATP in a linear fashion suggesting ongoing PRPP synthesis in red cells whose hemoglobin is deoxygenated. In contrast, a lesser increase of labelled ATP is observed in cells incubated under oxygen, suggesting that conditions for purine nucleotide formation from ambient Hy are more favorable in the venous circulation.

  19. Studies on the energy metabolism of opossum (Didelphis virginiana) erythrocytes: V. Utilization of hypoxanthine for the synthesis of adenine and guanine nucleotides in vitro

    International Nuclear Information System (INIS)

    High pressure liquid radiochromatography was used to test the ability of opossum erythrocytes to incorporate tracer amounts of [G-3H] hypoxanthine (Hy) into [3H] labelled triphosphates of adenine and guanine. In the presence of supraphysiologic (30 mM) phosphate which is optimal for PRPP synthesis, both ATP and GTP are extensively labelled. When physiologic (1 mM) medium phosphate is used, red cells incubated under an atmosphere of nitrogen accumulate [3H] ATP in a linear fashion suggesting ongoing PRPP synthesis in red cells whose hemoglobin is deoxygenated. In contrast, a lesser increase of labelled ATP is observed in cells incubated under oxygen, suggesting that conditions for purine nucleotide formation from ambient Hy are more favorable in the venous circulation

  20. Changes in phosphorylation of adenosine phosphate and redox state of nicotinamide-adenine dinucleotide (phosphate) in Geobacter sulfurreducens in response to electron acceptor and anode potential variation

    KAUST Repository

    Rose, Nicholas D.

    2015-12-01

    © 2015 Elsevier B.V. Geobacter sulfurreducens is one of the dominant bacterial species found in biofilms growing on anodes in bioelectrochemical systems. The intracellular concentrations of reduced and oxidized forms of nicotinamide-adenine dinucleotide (NADH and NAD+, respectively) and nicotinamide-adenine dinucleotide phosphate (NADPH and NADP+, respectively) as well as adenosine triphosphate (ATP), adenosine diphosphate (ADP), and adenosine monophosphate (AMP) were measured in G. sulfurreducens using fumarate, Fe(III)-citrate, or anodes poised at different potentials (110, 10, -90, and -190mV (vs. SHE)) as the electron acceptor. The ratios of CNADH/CNAD+ (0.088±0.022) and CNADPH/CNADP+ (0.268±0.098) were similar under all anode potentials tested and with Fe(III)-citrate (reduced extracellularly). Both ratios significantly increased with fumarate as the electron acceptor (0.331±0.094 for NAD and 1.96±0.37 for NADP). The adenylate energy charge (the fraction of phosphorylation in intracellular adenosine phosphates) was maintained near 0.47 under almost all conditions. Anode-growing biofilms demonstrated a significantly higher molar ratio of ATP/ADP relative to suspended cultures grown on fumarate or Fe(III)-citrate. These results provide evidence that the cellular location of reduction and not the redox potential of the electron acceptor controls the intracellular redox potential in G. sulfurreducens and that biofilm growth alters adenylate phosphorylation.

  1. Specificity of the ModA11, ModA12 and ModD1 epigenetic regulator N6-adenine DNA methyltransferases of Neisseria meningitidis

    Science.gov (United States)

    Seib, Kate L.; Jen, Freda E.-C.; Tan, Aimee; Scott, Adeana L.; Kumar, Ritesh; Power, Peter M.; Chen, Li-Tzu; Wu, Hsing-Ju; Wang, Andrew H.-J.; Hill, Dorothea M. C.; Luyten, Yvette A.; Morgan, Richard D.; Roberts, Richard J.; Maiden, Martin C. J.; Boitano, Matthew; Clark, Tyson A.; Korlach, Jonas; Rao, Desirazu N.; Jennings, Michael P.

    2015-01-01

    Phase variation (random ON/OFF switching) of gene expression is a common feature of host-adapted pathogenic bacteria. Phase variably expressed N6-adenine DNA methyltransferases (Mod) alter global methylation patterns resulting in changes in gene expression. These systems constitute phase variable regulons called phasevarions. Neisseria meningitidis phasevarions regulate genes including virulence factors and vaccine candidates, and alter phenotypes including antibiotic resistance. The target site recognized by these Type III N6-adenine DNA methyltransferases is not known. Single molecule, real-time (SMRT) methylome analysis was used to identify the recognition site for three key N. meningitidis methyltransferases: ModA11 (exemplified by M.NmeMC58I) (5′-CGYm6AG-3′), ModA12 (exemplified by M.Nme77I, M.Nme18I and M.Nme579II) (5′-ACm6ACC-3′) and ModD1 (exemplified by M.Nme579I) (5′-CCm6AGC-3′). Restriction inhibition assays and mutagenesis confirmed the SMRT methylome analysis. The ModA11 site is complex and atypical and is dependent on the type of pyrimidine at the central position, in combination with the bases flanking the core recognition sequence 5′-CGYm6AG-3′. The observed efficiency of methylation in the modA11 strain (MC58) genome ranged from 4.6% at 5′-GCGCm6AGG-3′ sites, to 100% at 5′-ACGTm6AGG-3′ sites. Analysis of the distribution of modified sites in the respective genomes shows many cases of association with intergenic regions of genes with altered expression due to phasevarion switching. PMID:25845594

  2. Regulation of Ca²⁺ release through inositol 1,4,5-trisphosphate receptors by adenine nucleotides in parotid acinar cells.

    Science.gov (United States)

    Park, Hyung Seo; Betzenhauser, Matthew J; Zhang, Yu; Yule, David I

    2012-01-01

    Secretagogue-stimulated intracellular Ca(2+) signals are fundamentally important for initiating the secretion of the fluid and ion component of saliva from parotid acinar cells. The Ca(2+) signals have characteristic spatial and temporal characteristics, which are defined by the specific properties of Ca(2+) release mediated by inositol 1,4,5-trisphosphate receptors (InsP(3)R). In this study we have investigated the role of adenine nucleotides in modulating Ca(2+) release in mouse parotid acinar cells. In permeabilized cells, the Ca(2+) release rate induced by submaximal [InsP(3)] was increased by 5 mM ATP. Enhanced Ca(2+) release was not observed at saturating [InsP(3)]. The EC(50) for the augmented Ca(2+) release was ∼8 μM ATP. The effect was mimicked by nonhydrolysable ATP analogs. ADP and AMP also potentiated Ca(2+) release but were less potent than ATP. In acini isolated from InsP(3)R-2-null transgenic animals, the rate of Ca(2+) release was decreased under all conditions but now enhanced by ATP at all [InsP(3)]. In addition the EC(50) for ATP potentiation increased to ∼500 μM. These characteristics are consistent with the properties of the InsP(3)R-2 dominating the overall features of InsP(3)R-induced Ca(2+) release despite the expression of all isoforms. Finally, Ca(2+) signals were measured in intact parotid lobules by multiphoton microscopy. Consistent with the release data, carbachol-stimulated Ca(2+) signals were reduced in lobules exposed to experimental hypoxia compared with control lobules only at submaximal concentrations. Adenine nucleotide modulation of InsP(3)R in parotid acinar cells likely contributes to the properties of Ca(2+) signals in physiological and pathological conditions.

  3. Data supporting the involvement of the adenine nucleotide translocase conformation in opening the Tl(+)-induced permeability transition pore in Ca(2+)-loaded rat liver mitochondria.

    Science.gov (United States)

    Korotkov, Sergey M

    2016-06-01

    There we made available information about the effects of the adenine nucleotide translocase (ANT) 'c' conformation fixers (phenylarsine oxide (PAO), tert-butylhydroperoxide (tBHP), and carboxyatractyloside) as well as thiol reagent (4,4'-diisothiocyanostilbene-2,2'-disulfonate (DIDS)) on isolated rat liver mitochondria. We observed a decrease in A540 (mitochondrial swelling) and respiratory control rates (RCRADP [state 3/state 4] and RCRDNP [2,4-dinitrophenol-uncoupled state/basal state or state 4]), as well as an increase in Ca(2+)-induced safranin fluorescence (F485/590, arbitrary units), showed a dissipation in the inner membrane potential (ΔΨmito), in experiments with energized rat liver mitochondria, injected into the buffer containing 25-75 mM TlNO3, 125 mM KNO3, and 100 µM Ca(2+). The fixers and DIDS, in comparison to Ca(2+) alone, greatly increased A540 decline and the rate of Ca(2+)-induced ΔΨmito dissipation. These reagents also markedly decreased RCRADP and RCRDNP. The MPTP inhibitors (ADP, cyclosporin A, bongkrekic acid, and N-ethylmaleimide) fixing the ANT in 'm' conformation significantly hindered the above-mentioned effects of the fixers and DIDS. A more complete scientific analysis of these findings may be obtained from the manuscript "To involvement the conformation of the adenine nucleotide translocase in opening the Tl(+)-induced permeability transition pore in Ca(2+)-loaded rat liver mitochondria" (Korotkov et al., 2016 [1]). PMID:27054168

  4. Diabetic complications within the context of aging: Nicotinamide adenine dinucleotide redox, insulin C-peptide, sirtuin 1-liver kinase B1-adenosine monophosphate-activated protein kinase positive feedback and forkhead box O3.

    Science.gov (United States)

    Ido, Yasuo

    2016-07-01

    Recent research in nutritional control of aging suggests that cytosolic increases in the reduced form of nicotinamide adenine dinucleotide and decreasing nicotinamide adenine dinucleotide metabolism plays a central role in controlling the longevity gene products sirtuin 1 (SIRT1), adenosine monophosphate-activated protein kinase (AMPK) and forkhead box O3 (FOXO3). High nutrition conditions, such as the diabetic milieu, increase the ratio of reduced to oxidized forms of cytosolic nicotinamide adenine dinucleotide through cascades including the polyol pathway. This redox change is associated with insulin resistance and the development of diabetic complications, and might be counteracted by insulin C-peptide. My research and others' suggest that the SIRT1-liver kinase B1-AMPK cascade creates positive feedback through nicotinamide adenine dinucleotide synthesis to help cells cope with metabolic stress. SIRT1 and AMPK can upregulate liver kinase B1 and FOXO3, key factors that help residential stem cells cope with oxidative stress. FOXO3 directly changes epigenetics around transcription start sites, maintaining the health of stem cells. 'Diabetic memory' is likely a result of epigenetic changes caused by high nutritional conditions, which disturb the quiescent state of residential stem cells and impair tissue repair. This could be prevented by restoring SIRT1-AMPK positive feedback through activating FOXO3. PMID:27181414

  5. Deficiency of the iron-sulfur clusters of mitochondrial reduced nicotinamide-adenine dinucleotide-ubiquinone oxidoreductase (complex I) in an infant with congenital lactic acidosis.

    Science.gov (United States)

    Moreadith, R W; Batshaw, M L; Ohnishi, T; Kerr, D; Knox, B; Jackson, D; Hruban, R; Olson, J; Reynafarje, B; Lehninger, A L

    1984-09-01

    We report the case of an infant with hypoglycemia, progressive lactic acidosis, an increased serum lactate/pyruvate ratio, and elevated plasma alanine, who had a moderate to profound decrease in the ability of mitochondria from four organs to oxidize pyruvate, malate plus glutamate, citrate, and other NAD+-linked respiratory substrates. The capacity to oxidize the flavin adenine dinucleotide-linked substrate, succinate, was normal. The most pronounced deficiency was in skeletal muscle, the least in kidney mitochondria. Enzymatic assays on isolated mitochondria ruled out defects in complexes II, III, and IV of the respiratory chain. Further studies showed that the defect was localized in the inner membrane mitochondrial NADH-ubiquinone oxidoreductase (complex I). When ferricyanide was used as an artificial electron acceptor, complex I activity was normal, indicating that electrons from NADH could reduce the flavin mononucleotide cofactor. However, electron paramagnetic resonance spectroscopy performed on liver submitochondrial particles showed an almost total loss of the iron-sulfur clusters characteristic of complex I, whereas normal signals were noted for other mitochondrial iron-sulfur clusters. This infant is presented as the first reported case of congenital lactic acidosis caused by a deficiency of the iron-sulfur clusters of complex I of the mitochondrial electron transport chain.

  6. To involvement the conformation of the adenine nucleotide translocase in opening the Tl(+)-induced permeability transition pore in Ca(2+)-loaded rat liver mitochondria.

    Science.gov (United States)

    Korotkov, Sergey M; Konovalova, Svetlana A; Brailovskaya, Irina V; Saris, Nils-Erik L

    2016-04-01

    The conformation of adenine nucleotide translocase (ANT) has a profound impact in opening the mitochondrial permeability transition pore (MPTP) in the inner membrane. Fixing the ANT in 'c' conformation by phenylarsine oxide (PAO), tert-butylhydroperoxide (tBHP), and carboxyatractyloside as well as the interaction of 4,4'-diisothiocyanostilbene-2,2'-disulfonate (DIDS) with mitochondrial thiols markedly attenuated the ability of ADP to inhibit the MPTP opening. We earlier found (Korotkov and Saris, 2011) that calcium load of rat liver mitochondria in medium containing TlNO3 and KNO3 stimulated the Tl(+)-induced MPTP opening in the inner mitochondrial membrane. The MPTP opening as well as followed increase in swelling, a drop in membrane potential (ΔΨmito), and a decrease in state 3, state 4, and 2,4-dinitrophenol-uncoupled respiration were visibly enhanced in the presence of PAO, tBHP, DIDS, and carboxyatractyloside. However, these effects were markedly inhibited by ADP and membrane-penetrant hydrophobic thiol reagent, N-ethylmaleimide (NEM) which fix the ANT in 'm' conformation. Cyclosporine A additionally potentiated these effects of ADP and NEM. Our data suggest that conformational changes of the ANT may be directly involved in the opening of the Tl(+)-induced MPTP in the inner membrane of Ca(2+)-loaded rat liver mitochondria. Using the Tl(+)-induced MPTP model is discussed in terms finding new transition pore inhibitors and inducers among different chemical and natural compounds. PMID:26835787

  7. Bisamidate Prodrugs of 2-Substituted 9-[2-(Phosphonomethoxy)ethyl]adenine (PMEA, adefovir) as Selective Inhibitors of Adenylate Cyclase Toxin from Bordetella pertussis.

    Science.gov (United States)

    Česnek, Michal; Jansa, Petr; Šmídková, Markéta; Mertlíková-Kaiserová, Helena; Dračínský, Martin; Brust, Tarsis F; Pávek, Petr; Trejtnar, František; Watts, Val J; Janeba, Zlatko

    2015-08-01

    Novel small-molecule agents to treat Bordetella pertussis infections are highly desirable, as pertussis (whooping cough) remains a serious health threat worldwide. In this study, a series of 2-substituted derivatives of 9-[2-(phosphonomethoxy)ethyl]adenine (PMEA, adefovir), in their isopropyl ester bis(L-phenylalanine) prodrug form, were designed and synthesized as potent inhibitors of adenylate cyclase toxin (ACT) isolated from B. pertussis. The series consists of PMEA analogues bearing either a linear or branched aliphatic chain or a heteroatom at the C2 position of the purine moiety. Compounds with a small C2 substituent showed high potency against ACT without cytotoxic effects as well as good selectivity over human adenylate cyclase isoforms AC1, AC2, and AC5. The most potent ACT inhibitor was found to be the bisamidate prodrug of the 2-fluoro PMEA derivative (IC50 =0.145 μM). Although the bisamidate prodrugs reported herein exhibit overall lower activity than the bis(pivaloyloxymethyl) prodrug (adefovir dipivoxil), their toxicity and plasma stability profiles are superior. Furthermore, the bisamidate prodrug was shown to be more stable in plasma than in macrophage homogenate, indicating that the free phosphonate can be effectively distributed to target tissues, such as the lungs. Thus, ACT inhibitors based on acyclic nucleoside phosphonates may represent a new strategy to treat whooping cough.

  8. Gender and chronological age affect erythrocyte membrane oxidative indices in citrate phosphate dextrose adenine-formula 1 (CPDA-1) blood bank storage condition.

    Science.gov (United States)

    Erman, Hayriye; Aksu, Uğur; Belce, Ahmet; Atukeren, Pınar; Uzun, Duygu; Cebe, Tamer; Kansu, Ahmet D; Gelişgen, Remisa; Uslu, Ezel; Aydın, Seval; Çakatay, Ufuk

    2016-07-01

    It is well known that in vitro storage lesions lead to membrane dysfunction and decreased number of functional erythrocytes. As erythrocytes get older, in storage media as well as in peripheral circulation, they undergo a variety of biochemical changes. In our study, the erythrocytes with different age groups in citrate phosphate dextrose adenine-formula 1 (CPDA-1) storage solution were used in order to investigate the possible effect of gender factor on oxidative damage. Oxidative damage biomarkers in erythrocyte membranes such as ferric reducing antioxidant power, pro-oxidant-antioxidant balance, protein-bound advance glycation end products, and sialic acid were analyzed. Current study reveals that change in membrane redox status during blood-bank storage condition also depends on both gender depended homeostatic factors and the presence of CPDA-1. During the storage period in CPDA-1, erythrocytes from the male donors are mostly affected by free radical-mediated oxidative stress but erythrocytes obtained from females are severely affected by glyoxidative stress.

  9. An adenine nucleotide translocase (ANT) gene from Apostichopus japonicus; molecular cloning and expression analysis in response to lipopolysaccharide (LPS) challenge and thermal stress.

    Science.gov (United States)

    Liu, Qiu-Ning; Chai, Xin-Yue; Tu, Jie; Xin, Zhao-Zhe; Li, Chao-Feng; Jiang, Sen-Hao; Zhou, Chun-Lin; Tang, Bo-Ping

    2016-02-01

    The adenine nucleotide translocases (ANTs) play a vital role in energy metabolism via ADP/ATP exchange in eukaryotic cells. Apostichopus japonicus (Echinodermata: Holothuroidea) is an important economic species in China. Here, a cDNA representing an ANT gene of A. japonicus was isolated and characterized from respiratory tree and named AjANT. The full-length AjANT cDNA is 1924 bp, including a 5'-untranslated region (UTR) of 38 bp, 3'-UTR of 980 bp and an open reading frame (ORF) of 906 bp encoding a polypeptide of 301 amino acids. The protein contains three homologous repeat Mito_carr domains (Pfam00153). The deduced AjANT protein sequence has 49-81% in comparison to ANT proteins from other individuals. The predicted tertiary structure of AjANT protein is highly similar to animal ANT proteins. Phylogenetic analysis showed that the AjANT is closely related to Holothuroidea ANT genes. Real-time quantitative reverse transcription-PCR (qPCR) analysis showed that AjANT expression is higher in the respiratory tree than in other examined tissues. After thermal stress or LPS challenge, expression of AjANT was significantly fluctuant compared to the control. These results suggested that changes in the expression of ANT gene might be involved in immune defense and in protecting A. japonicus against thermal stress. PMID:26706223

  10. Determination of guanine and adenine by high-performance liquid chromatography with a self-fabricated wall-jet/thin-layer electrochemical detector at a glassy carbon electrode.

    Science.gov (United States)

    Zhou, Yaping; Yan, Hongling; Xie, Qingji; Yao, Shouzhuo

    2015-03-01

    A sensitive wall-jet/thin-layer amperometric electrochemical detector (ECD) coupled to high-performance liquid chromatography (HPLC) was developed for simultaneous determination of guanine (G) and adenine (A). The analytes were detected at a glassy carbon electrode (GCE) and the HPLC-ECD calibration curves showed good linearity (R(2)>0.997) under optimized conditions. Limits of detection for G and A are 0.6 nM and 1.4 nM (S/N=3), respectively, which are lower than those obtained with an UV-vis detector and a commercial electrochemical detector. We have successfully applied this HPLC-ECD to assess the contents of G and A in hydrochloric acid-digested calf thymus double-stranded DNA. In addition, we compared in detail the analysis of G and A by cyclic voltammetry (CV) and by the HPLC-ECD system on both bare GCE and electroreduced graphene oxide (ERGO) modified GCE. We found that the adsorption of G and A on the electrode surfaces can vary their anodic CV peaks and the competitive adsorption of G and A on the limited sites of the electrode surfaces can cause crosstalk effects on their anodic CV peak signals, but the HPLC-ECD system is insensitive to such electrode-adsorption and can give more reliable analytical results. PMID:25618679

  11. A study of fast and metastable dissociations of adenine-thymine binary-base oligonucleotides by using positive-ion MALDI-TOF mass spectrometry.

    Science.gov (United States)

    Chan, T W Dominic; Fung, Y M Eva; Li, Y C Leo

    2002-09-01

    In the present study, fast and metastable dissociations of a number of adenine-thymine binary-base oligonucleotides under the conditions of UV matrix-assisted laser desorption/ionization mass spectrometry were investigated. 2-Aminobenzoic acid/ammonium fluoride (ABA/NH4F) matrix system was used. The spectra obtained under metastable and fast dissociation conditions exhibit distinctive dissociation products. From the post-source-decay analysis, all oligonucleotides underwent predominantly metastable dissociations at the 3' C-O linkages to form [a(n)-B]+ and w(n)+ complimentary ion series. Based on the present results, the so-called "[wn+80]+" ions were postulated to be the complimentary [Z(8-n)AH]+ ions rather than the expected phosphate rearrangement products. In addition, these oligonucleotides were found to generate fast dissociation products of b(n)+, d(N)+, w(N)+ and y(N)+ ions through backbone cleavages at 5' C-O, 5' O-P, 3' C-O and 3' P-O linkages, respectively. Product ion series formed under PSD conditions were not observed. The implications of this mutually exclusive occurrence of the two sets of fragment ions under fast and metastable conditions using ABA/NH4F matrix would be discussed. A model of ion activation under UV-MALDI conditions was also proposed. PMID:12322953

  12. Specificities and pH profiles of adenine and hypoxanthine-guanine-xanthine phosphoribosyltransferases (nucleotide synthases) of the thermoacidophile archaeon Sulfolobus solfataricus

    DEFF Research Database (Denmark)

    Hansen, Michael Riis; Jensen, Kristine Steen; Rasmussen, Mads Skytte;

    2014-01-01

    Two open reading frames in the genome of Sulfolobus solfataricus (SSO2341 and SSO2424) were cloned and expressed in E. coli. The protein products were purified and their enzymatic activity characterized. Although SSO2341 was annotated as a gene (gpT-1) encoding a 6-oxopurine phosphoribosyltransfe......Two open reading frames in the genome of Sulfolobus solfataricus (SSO2341 and SSO2424) were cloned and expressed in E. coli. The protein products were purified and their enzymatic activity characterized. Although SSO2341 was annotated as a gene (gpT-1) encoding a 6-oxopurine...... phosphoribosyltransferase (PRTase), the protein product turned out to be a PRTase highly specific for adenine and we suggest that the reading frame should be renamed apT. The other reading frame SSO2424 (gpT-2) proved to be a true 6-oxopurine PRTase active with hypoxanthine, xanthine and guanine as substrates, and we.......5, while maximal activity with xanthine was observed at pH 7.5. We discuss likely reasons why SSO2341 in S. solfataricus and similar open reading frames in other Crenarchaeota could not be identified as genes encoding APRTase....

  13. Excessive Copper Induces the Production of Reactive Oxygen Species, which is Mediated by Phospholipase D, Nicotinamide Adenine Dinucleotide Phosphate Oxidase and Antioxidant Systems

    Institute of Scientific and Technical Information of China (English)

    Zhong-Lian Yu; Jin-Guang Zhang; Xue-Chen Wang; Jia Chen

    2008-01-01

    Tobacco BY-2 suspension cells were used to study the chemical damage and its associated mechanisms caused by Cu2+. Treatment with 100 μmol/L Cu2+ generated a large amount of H2O2 and thiobarbituric acid-reactive substances (TBARS) in cells. Using phospholipase D (PLD) specific inhibitor (1-butanol) or phosphatidic acid (PA), we demonstrated that PLD plays an important role in the generation of H2O2 and TBARS. Semi-quantitative reverse-transcriptase polymerase chain reaction and enzyme activity assays with wild type and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase- overexpressing BY-2 cells revealed that PLD and PA are the key factors leading to NADPH oxidase activation, which is responsible for H2O2 and TBARS production induced by Cu2+. Moreover, the content of ascorbic acid (AsA), an effective antioxidant, was sharply reduced in BY-2 cells exposed to excessive Cu2+. Furthermore, a significant downregulation of the enzymes of AsA biosynthesis and the antioxidant system was found. This evidencesuggests that excessive Cu2+-elevated reactive oxygen species (ROS) production is caused by upregulated PLD that elevates the activity of NADPH oxidase and its collapsed antioxidant systems that scavenges ROS.

  14. Deficiency of the iron-sulfur clusters of mitochondrial reduced nicotinamide-adenine dinucleotide-ubiquinone oxidoreductase (complex I) in an infant with congenital lactic acidosis.

    Science.gov (United States)

    Moreadith, R W; Batshaw, M L; Ohnishi, T; Kerr, D; Knox, B; Jackson, D; Hruban, R; Olson, J; Reynafarje, B; Lehninger, A L

    1984-09-01

    We report the case of an infant with hypoglycemia, progressive lactic acidosis, an increased serum lactate/pyruvate ratio, and elevated plasma alanine, who had a moderate to profound decrease in the ability of mitochondria from four organs to oxidize pyruvate, malate plus glutamate, citrate, and other NAD+-linked respiratory substrates. The capacity to oxidize the flavin adenine dinucleotide-linked substrate, succinate, was normal. The most pronounced deficiency was in skeletal muscle, the least in kidney mitochondria. Enzymatic assays on isolated mitochondria ruled out defects in complexes II, III, and IV of the respiratory chain. Further studies showed that the defect was localized in the inner membrane mitochondrial NADH-ubiquinone oxidoreductase (complex I). When ferricyanide was used as an artificial electron acceptor, complex I activity was normal, indicating that electrons from NADH could reduce the flavin mononucleotide cofactor. However, electron paramagnetic resonance spectroscopy performed on liver submitochondrial particles showed an almost total loss of the iron-sulfur clusters characteristic of complex I, whereas normal signals were noted for other mitochondrial iron-sulfur clusters. This infant is presented as the first reported case of congenital lactic acidosis caused by a deficiency of the iron-sulfur clusters of complex I of the mitochondrial electron transport chain. PMID:6432847

  15. Nicotinic Acid Adenine Dinucleotide Phosphate (NAADP)-mediated Calcium Signaling and Arrhythmias in the Heart Evoked by β-Adrenergic Stimulation*♦

    Science.gov (United States)

    Nebel, Merle; Schwoerer, Alexander P.; Warszta, Dominik; Siebrands, Cornelia C.; Limbrock, Ann-Christin; Swarbrick, Joanna M.; Fliegert, Ralf; Weber, Karin; Bruhn, Sören; Hohenegger, Martin; Geisler, Anne; Herich, Lena; Schlegel, Susan; Carrier, Lucie; Eschenhagen, Thomas; Potter, Barry V. L.; Ehmke, Heimo; Guse, Andreas H.

    2013-01-01

    Nicotinic acid adenine dinucleotide phosphate (NAADP) is the most potent Ca2+-releasing second messenger known to date. Here, we report a new role for NAADP in arrhythmogenic Ca2+ release in cardiac myocytes evoked by β-adrenergic stimulation. Infusion of NAADP into intact cardiac myocytes induced global Ca2+ signals sensitive to inhibitors of both acidic Ca2+ stores and ryanodine receptors and to NAADP antagonist BZ194. Furthermore, in electrically paced cardiac myocytes BZ194 blocked spontaneous diastolic Ca2+ transients caused by high concentrations of the β-adrenergic agonist isoproterenol. Ca2+ transients were recorded both as increases of the free cytosolic Ca2+ concentration and as decreases of the sarcoplasmic luminal Ca2+ concentration. Importantly, NAADP antagonist BZ194 largely ameliorated isoproterenol-induced arrhythmias in awake mice. We provide strong evidence that NAADP-mediated modulation of couplon activity plays a role for triggering spontaneous diastolic Ca2+ transients in isolated cardiac myocytes and arrhythmias in the intact animal. Thus, NAADP signaling appears an attractive novel target for antiarrhythmic therapy. PMID:23564460

  16. Identification of a compound heterozygote for adenine phosphoribosyltransferase deficiency (APRT*J/APART*Q0) leading to 2,8-dihydroxyadenine urolithiasis.

    Science.gov (United States)

    Kamatani, N; Kuroshima, S; Yamanaka, H; Nakashe, S; Take, H; Hakoda, M

    1990-10-01

    Homozygous deficiency of a purine salvage enzyme, adenine phosphoribosyltransferase (APRT), causes urolithiasis and renal failure. There are two known types of homozygous APRT deficiencies; type I patients completely lack APRT activity while type II patients only partially lack such activity. All type II patients possess at least one APRT*J allele with a substitution from ATG (Met) to ACG (Thr) at codon 136. Type I patients are considered to possess two alleles (APRT*Q0) both of which code for complete deficiencies. Thus, some patients with type II APRT deficiencies may have a genotype of APRT*J/APRT*Q0. As no individuals with such a genotype have previously been identified, we performed extensive analysis on four members of a family by (1) the T-cell method for the identification of a homozygote, (2) the B-cell method for the identification of heterozygotes, and (3) oligonucleotide hybridization after in vitro amplification of a part of genomic APRT sequence for the identification of APRT*J and non-APRT*J alleles. We report here the first evidence that 2,8-dihydroxyadenine urolithiasis developed in a boy aged 2 years with a genotype of APRT*J/APRT*Q0.

  17. Wear Particles Promote Reactive Oxygen Species-Mediated Inflammation via the Nicotinamide Adenine Dinucleotide Phosphate Oxidase Pathway in Macrophages Surrounding Loosened Implants

    Directory of Open Access Journals (Sweden)

    Weishen Chen

    2015-03-01

    Full Text Available Background/Aims: Prosthesis loosening is closely associated with chronic inflammatory cytokine secretion by macrophages, which are activated by wear particles or inflammatory stimulants such as lipopolysaccharide (LPS. Reactive oxygen species (ROS are critical regulators of inflammation, but their enzymatic sources in response to wear particles and their effects on peri-implant LPS-tolerance remain unclear. Methods: Three ROS-related enzymes—nicotinamide adenine dinucleotide phosphate oxidase (NOX-1 and -2 and catalase—were investigated in interface membrane tissues and in titanium (Ti particle-stimulated macrophages in vitro. The generation of ROS and downstream inflammatory effects were measured with or without pre-incubation with apocynin, an NOX inhibitor. Results: Pre-exposure to Ti particles attenuated NF-κB activation in LPS-stimulated macrophages, indicating that wear particles suppress immune response, which may lead to chronic inflammation. NOX-1 and -2 were highly expressed in aseptically loosened interface membranes and in macrophages stimulated with Ti particles; the particles induced a moderate amount of ROS generation, NF-κB activation, and TNF-a secretion in macrophages, and these effects were suppressed by apocynin. Conclusion: Wear particles induce ROS generation through the NOX signaling pathway, resulting in persistent inflammation and delayed loosening. Thus, the suppression of NOX activity may be a useful strategy for preventing prosthesis loosening.

  18. Nitrogen Substituted Polycyclic Aromatic Hydrocarbon As Capable Interstellar Infrared Spectrum Source Considering Astronomical Chemical Evolution Step To Biological Organic Purine And Adenine

    CERN Document Server

    Ota, Norio

    2016-01-01

    In order to find out capable chemical evolution step from astronomically created organic in interstellar space to biological organic on the earth, infrared spectrum of nitrogen substituted carbon pentagon-hexagon coupled polycyclic aromatic hydrocarbon was analyzed by the density functional theory. Ionization was modeled from neutral to tri-cation. Among one nitrogen and two nitrogen substituted NPAH, we could find good examples showing similar IR behavior with astronomically well observed one as like C8H6N1, C7H5N2, and C7H5N2. We can imagine that such ionized NPAH may be created in interstellar space by attacks of high energy nitrogen and photon. Whereas, in case of three and four nitrogen substituted cases as like C6H4N3 and C5H3N4, there were no candidate showing similar behavior with observed one. Also, IR of typical biological organic with four and five nitrogen substituted one as like purine and adenine resulted no good similarity with observed one. By such theoretical comparison, one capable story of ...

  19. Increase of reduced nicotinamide adenine dinucleotide fluorescence lifetime precedes mitochondrial dysfunction in staurosporine-induced apoptosis of HeLa cells

    Science.gov (United States)

    Yu, Jia-Sin; Guo, Han-Wen; Wang, Chih-Hao; Wei, Yau-Huei; Wang, Hsing-Wen

    2011-03-01

    In vivo noninvasive detection of apoptosis represents a new tool that may yield a more definite diagnosis, a more accurate prognosis, and help improve therapies for human diseases. The intrinsic fluorescence of reduced nicotinamide adenine dinucleotide (NADH) may be a potential optical biomarker for the apoptosis detection because NADH is involved in the respiration for the mitochondrial membrane potential (ΔΨ) formation and adenosine-5'-triphosphate (ATP) synthesis, and the depletion of ΔΨ and ATP level is the hallmark of apoptosis. We have previously observed the NADH fluorescence lifetime change is associated with staurosporine (STS)-induced mitochondria-mediated apoptosis. However, its relationship with mitochondrial functions such as ΔΨ, ATP, and oxygen consumption rate is not clear. In this study, we investigated this relationship. Our results indicate that the NADH fluorescence lifetime increased when ΔΨ and ATP levels were equal to or higher than their values of controls and decreased before the depletion of ΔΨ and ATP, and the oxygen consumption rate did not change. These findings suggest that the increased NADH fluorescence lifetime in STS-induced cell death occurred before the depletion of ΔΨ and ATP and activation of caspase 3, and was not simply caused by cellular metabolic change. Furthermore, the NADH fluorescence lifetime change is associated with the pace of apoptosis.

  20. An adenine-to-guanine nucleotide change in the IRES SL-IV domain of picornavirus/hepatitis C chimeric viruses leads to a nonviable phenotype

    International Nuclear Information System (INIS)

    The inability for the internal ribosomal entry site (IRES) of hepatitis C virus (HCV) to be readily studied in the context of viral replication has been circumvented by constructing chimeras such as with poliovirus (PV), in which translation of the genome polyprotein is under control of the HCV IRES. During our attempts to configure the PV/HCV chimera for our drug discovery efforts, we discovered that an adenine- (A) to-guanine (G) change at nt 350 in domain IV of the HCV IRES resulted in a nonviable phenotype. Similarly, a mengovirus (MV)/HCV chimera using the same configuration with a G at nt 350 (G-350) was found to be nonviable. In contrast, a bovine viral diarrhea virus (BVDV)/HCV chimera remained viable with G-350 in the HCV IRES insert. Second-site, resuscitating mutations were identified from the G-350 PV/HCV and MV/HCV viruses after blind passaging. For both viruses, the resuscitating mutations involved destabilization of domain IV in the HCV IRES. The nonviability of G-350 in the picornavirus/HCV chimeric background might be linked to translation efficiency as indicated by analyses with dual reporter and PV/HCV replicon constructs

  1. β-Nicotinamide adenine dinucleotide acts at prejunctional adenosine A1 receptors to suppress inhibitory musculomotor neurotransmission in guinea pig colon and human jejunum.

    Science.gov (United States)

    Wang, Guo-Du; Wang, Xi-Yu; Liu, Sumei; Xia, Yun; Zou, Fei; Qu, Meihua; Needleman, Bradley J; Mikami, Dean J; Wood, Jackie D

    2015-06-01

    Intracellular microelectrodes were used to record neurogenic inhibitory junction potentials in the intestinal circular muscle coat. Electrical field stimulation was used to stimulate intramural neurons and evoke contraction of the smooth musculature. Exposure to β-nicotinamide adenine dinucleotide (β-NAD) did not alter smooth muscle membrane potential in guinea pig colon or human jejunum. ATP, ADP, β-NAD, and adenosine, as well as the purinergic P2Y1 receptor antagonists MRS 2179 and MRS 2500 and the adenosine A1 receptor agonist 2-chloro-N6-cyclopentyladenosine, each suppressed inhibitory junction potentials in guinea pig and human preparations. β-NAD suppressed contractile force of twitch-like contractions evoked by electrical field stimulation in guinea pig and human preparations. P2Y1 receptor antagonists did not reverse this action. Stimulation of adenosine A1 receptors with 2-chloro-N6-cyclopentyladenosine suppressed the force of twitch contractions evoked by electrical field stimulation in like manner to the action of β-NAD. Blockade of adenosine A1 receptors with 8-cyclopentyl-1,3-dipropylxanthine suppressed the inhibitory action of β-NAD on the force of electrically evoked contractions. The results do not support an inhibitory neurotransmitter role for β-NAD at intestinal neuromuscular junctions. The data suggest that β-NAD is a ligand for the adenosine A1 receptor subtype expressed by neurons in the enteric nervous system. The influence of β-NAD on intestinal motility emerges from adenosine A1 receptor-mediated suppression of neurotransmitter release at inhibitory neuromuscular junctions.

  2. Spectroscopy and Speciation Studies on the Interactions of Aluminum (III with Ciprofloxacin and β-Nicotinamide Adenine Dinucleotide Phosphate in Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    Xiaodi Yang

    2012-08-01

    Full Text Available In this study, both experimental and theoretical approaches, including absorption spectra, fluorescence emission spectra, 1H- and 31P-NMR, electrospray ionization mass spectrometry (ESI-MS, pH-potentiometry and theoretical approaches using the BEST & SPE computer programs were applied to study the competitive complexation between ciprofloxacin (CIP and b-nicotinamide adenine dinucleotide phosphate (NADP with aluminum (III in aqueous solutions. Rank annihilation factor analysis (RAFA was used to analyze the absorption and fluorescence emission spectra of the ligands, the binary complexes and the ternary complexes. It is found, at the mM total concentration level and pH = 7.0, the bidentate mononuclear species [Al(CIP]2+ and [Al(NADP] predominate in the aqueous solutions of the Al(III-CIP and Al(III-NADP systems, and the two complexes have similar conditional stability constants. However, the pH-potentiometry results show at the mM total concentration level and pH = 7.0, the ternary species [Al(CIP(HNADP] predominates in the ternary complex system. Comparing predicted NMR spectra with the experimental NMR results, it can be concluded that for the ternary complex, CIP binds to aluminum ion between the 3-carboxylic and 4-carbonyl groups, while the binding site of oxidized coenzyme II is through the oxygen of phosphate, which is linked to adenosine ribose, instead of pyrophosphate. The results also suggested CIP has the potential to be a probe molecular for the detection of NADP and the Al(III-NADP complexes under physiological condition.

  3. Ryanodine receptor type I and nicotinic acid adenine dinucleotide phosphate receptors mediate Ca2+ release from insulin-containing vesicles in living pancreatic beta-cells (MIN6).

    Science.gov (United States)

    Mitchell, Kathryn J; Lai, F Anthony; Rutter, Guy A

    2003-03-28

    We have demonstrated recently (Mitchell, K. J., Pinton, P., Varadi, A., Tacchetti, C., Ainscow, E. K., Pozzan, T., Rizzuto, R., and Rutter, G. A. (2001) J. Cell Biol. 155, 41-51) that ryanodine receptors (RyR) are present on insulin-containing secretory vesicles. Here we show that pancreatic islets and derived beta-cell lines express type I and II, but not type III, RyRs. Purified by subcellular fractionation and membrane immuno-isolation, dense core secretory vesicles were found to possess a similar level of type I RyR immunoreactivity as Golgi/endoplasmic reticulum (ER) membranes but substantially less RyR II than the latter. Monitored in cells expressing appropriately targeted aequorins, dantrolene, an inhibitor of RyR I channels, elevated free Ca(2+) concentrations in the secretory vesicle compartment from 40.1 +/- 6.7 to 90.4 +/- 14.8 microm (n = 4, p < 0.01), while having no effect on ER Ca(2+) concentrations. Furthermore, nicotinic acid adenine dinucleotide phosphate (NAADP), a novel Ca(2+)-mobilizing agent, decreased dense core secretory vesicle but not ER free Ca(2+) concentrations in permeabilized MIN6 beta-cells, and flash photolysis of caged NAADP released Ca(2+) from a thapsigargin-insensitive Ca(2+) store in single MIN6 cells. Because dantrolene strongly inhibited glucose-stimulated insulin secretion (from 3.07 +/- 0.51-fold stimulation to no significant glucose effect; n = 3, p < 0.01), we conclude that RyR I-mediated Ca(2+)-induced Ca(2+) release from secretory vesicles, possibly potentiated by NAADP, is essential for the activation of insulin secretion.

  4. Effect of telmisartan on the expression of adiponectin receptors and nicotinamide adenine dinucleotide phosphate oxidase in the heart and aorta in type 2 diabetic rats

    Directory of Open Access Journals (Sweden)

    Guo Zhixin

    2012-08-01

    Full Text Available Abstract Background Diabetic cardiovascular disease is associated with decreased adiponectin and increased oxidative stress. This study investigated the effect of telmisartan on the expression of adiponectin receptor 2 (adipoR2 and nicotinamide adenine dinucleotide phosphate (NADPH oxidase subunits in the heart and the expression of adiponectin receptor 1 (adipoR1 in aorta in type 2 diabetic rats. Methods Type 2 diabetes was induced by high-fat and high-sugar diet and intraperitoneal injection of a low dose of streptozotocin (STZ. Heart function, adipoR2, p22phox, NOX4, glucose transporter 4(GLUT4, monocyte chemoattractant protein-1(MCP-1 and connective tissue growth factor (CTGFin the heart, and adipoR1, MCP-1 and nuclear factor kappa B (NF-κB in aorta were analyzed in controls and diabetic rats treated with or without telmisartan (5mg/kg/d by gavage for 12 weeks. Results Heart function, plasma and myocardial adiponectin levels, the expression of myocardial adipoR2 and GLUT4 were significantly decreased in diabetic rats (P Conclusions Our results suggest that telmisartan upregulates the expression of myocardial adiponectin, its receptor 2 and GLUT4. Simultaneously, it downregulates the expression of myocardial p22phox, NOX4, MCP-1, and CTGF, contributing so to the improvement of heart function in diabetic rats. Telmisartan also induces a protective role on the vascular system by upregulating the expression of adipoR1 and downregulating the expression of MCP-1 and NF-κB in the abdominal aorta in diabetic rats.

  5. The regulation of respiration of guinea pig taenia coli in high-K medium: the role of nicotinamide-adenine dinucleotide, adenosine diphosphate and Ca++.

    Science.gov (United States)

    Tsuda, S; Urakawa, N; Saito, Y; Fukami, J

    1975-10-01

    In an attempt to elucidate the regulation mechanism of respiration in the smooth muscle cell, we investigated the roles of nicotinamide-adenine dinucleotide (NAD), adenosine diphosphate (ADP) and Ca++ in the muscle respiration using the tissues and subcellular fractions from guinea pig taenia coli. The tension in the strips of taenia coli increased with a concomitant increase in O2 consumption in high-K medium (40 mM K) containing 2.5 mM Ca. 10(-3) M amytal and 10(-5)M ouabain decreased the high-K induced tension and O2 consumption of the muscle. 10(-4)M 2,4-dinitrophenol (DNP) relieved the decreased respiration induced by ouabain, but not that with amytal. From these data it is suggested that NADH-linked respiration plays an important role in the respiration of the muscle. Ca++ in concentrations ranging from 0.5 to 2.5 mM in the high-K medium resulted in an increase in tension and in O2 concumption progressively. In spectrophotometric observations of subcellular fractions of the taenia coli, ADP increased in absorbance change at 340 m mu. Such occurred in mitochondrial fractions and was initiated by the addition of NADH. Therefore it is deduced that the increase in ADP level of the cytoplasm is primarily due to a contraction triggered by Ca++ thus stimulating respiration. On the other hand, at 0.1 mM of Ca++ concentration, the muscle strip increased O2 consumption without tension development in high-K medium. In the spectrophotometric observations, Ca++ and Sr++ increased the absorbance change in the homogenate and in the mitochondrial fraction. Hence, it seems that one part of the Ca++ entering into the smooth muscle treated with the high-K increased O2 consumption in mitochondia independent of an increase in muscle tension. From these results it is concluded that NADH-linked respiration plays an important role in the smooth muscle respiration in high-K medium and that ADP and Ca++ also play a role in regulating respiration. PMID:176493

  6. Nicotinamide Adenine Dinucleotide Phosphate Oxidase-Mediated Redox Signaling and Vascular Remodeling by 16α-Hydroxyestrone in Human Pulmonary Artery Cells: Implications in Pulmonary Arterial Hypertension.

    Science.gov (United States)

    Hood, Katie Y; Montezano, Augusto C; Harvey, Adam P; Nilsen, Margaret; MacLean, Margaret R; Touyz, Rhian M

    2016-09-01

    Estrogen and oxidative stress have been implicated in pulmonary arterial hypertension (PAH). Mechanisms linking these systems are elusive. We hypothesized that estrogen metabolite, 16α-hydroxyestrone (16αOHE1), stimulates nicotinamide adenine dinucleotide phosphate oxidase (Nox)-induced reactive oxygen species (ROS) generation and proliferative responses in human pulmonary artery smooth muscle cells (hPASMCs) and that in PAH aberrant growth signaling promotes vascular remodeling. The pathophysiological significance of estrogen-Nox-dependent processes was studied in female Nox1(-/-) and Nox4(-/-) mice with PAH. PASMCs from control subjects (control hPASMCs) and PAH patients (PAH-hPASMCs) were exposed to estrogen and 16αOHE1 in the presence/absence of inhibitors of Nox, cytochrome P450 1B1, and estrogen receptors. Estrogen, through estrogen receptor-α, increased Nox-derived ROS and redox-sensitive growth in hPASMCs, with greater effects in PAH-hPASMCs versus control hPASMCs. Estrogen effects were inhibited by cytochrome P450 1B1 blockade. 16αOHE1 stimulated transient ROS production in hPASMCs, with sustained responses in PAH-hPASMCs. Basal expression of Nox1/Nox4 was potentiated in PAH-hPASMCs. In hPASMCs, 16αOHE1 increased Nox1 expression, stimulated irreversible oxidation of protein tyrosine phosphatases, decreased nuclear factor erythroid-related factor 2 activity and expression of nuclear factor erythroid-related factor 2-regulated antioxidant genes, and promoted proliferation. This was further amplified in PAH-hPASMCs. Nox1(-/-) but not Nox4(-/-) mice were protected against PAH and vascular remodeling. Our findings demonstrate that in PAH-hPASMCs, 16αOHE1 stimulates redox-sensitive cell growth primarily through Nox1. Supporting this, in vivo studies exhibited protection against pulmonary hypertension and remodeling in Nox1(-/-) mice. This study provides new insights through Nox1/ROS and nuclear factor erythroid-related factor 2 whereby 16αOHE1 influences

  7. 基于SERS光谱的银溶胶溶液中腺嘌呤的定量分析%Quantitative Analysis with Adenine in Silver Colloidal Sol by Surface-enhanced Raman Scattering Spectroscopic Technique

    Institute of Scientific and Technical Information of China (English)

    冯小平; 曹晓卫; 汪佳俐; 李玲; 张志学

    2012-01-01

    Surface-enhanced Raman scattering (SERS) spectroscopic technique was used to perform quantitative analyses with adenine, an important basic group from nucleic acid, by using silver colloidal sol as the SERS substrate. Sodium polyacrylate was added into the silver colloidal sol in order to improve its stability. In addition, during different SERS measurements, pyridine was used an internal standard to eliminate the impact of the variations in laser power, optical alignment and focusing on the SERS signal intensity of the an-alyte. It reveals that a good linear relationship is presented between the concentration of adenine and the characteristic SERS signal intensity ratio of the analyte adenine (733 cm-1) to the internal standard pyridine (1003 cm-1) in the range of 1× 10-4~1× 10-3mol ·L-1.%碱基是构成核酸的物质基础.碱基的含量分析对于生物体的生理活动及新陈代谢过程研究具有重要意义.本文利用表面增强拉曼散射(SERS)光谱技术研究了腺嘌呤在相对稳定的银溶胶溶液中的SERS光谱信号强度与浓度的定量关系.研究表明添加聚合物作为稳定剂的银溶胶具有良好的稳定性.进一步研究表明,在1×10-4~1×10-2mol·L-1的浓度范围内,以吡啶作为内标,分析物腺嘌呤与内标物特征谱峰强度之比与腺嘌呤的浓度之间呈现良好的线性关系.

  8. Netropsin . dG-dG-dA-dA-dT-dT-dC-dC complex. Antibiotic binding at adenine . thymine base pairs in the minor groove of the self-complementary octanucleotide duplex.

    Science.gov (United States)

    Patel, D J

    1979-09-01

    The structure of the netropsin . dG-dG-dA-dA-dT-dT-dC-dC complex (one antibiotic molecule/self-complementary octanucleodide duplex) and its dynamics as a function of temperature have been monitored by the nuclear magnetic resonances of the Watson-Crick protons, the nonexchangeable base and sugar protons and the backbone phosphates. The antibiotic forms a complex with the nucleic acid duplex at the dA . dT-containing tetranucleotide segment dA-dA-dT-dT, with slow migration amongst potential binding sites at low temperature. The downfield shifts in the exchangeable protons of netropsin on complex formation demonstrate the contributions of hydrogen-bonding interactions between the antibiotic and the nucleic acid to the stability of the complex. Complex formation results in changes in the glycosidic torsion angles of both thymidine residues and one deoxyadenosine residue as monitored by chemical shift changes in the thymine C-6 and adenine C-8 protons. The close proximity of the pyrrole rings of the antibiotic and the base-pair edges in the minor groove is manifested in the downfield shifts (0.3--0.5 ppm) of the pyrrole C-3 protons of netropsin and one adenine C-2 proton and one thymine N-3 base-pair proton on complex formation. The internucleotide phosphates of the octanucleotide undergo 31P chemical shift changes on addition of netropsin and these may reflect, in part, contributions from electrostatic interactions between the charged ends of the antibiotic and the backbone phosphates of the nucleic acid.

  9. Molecular characterization of Fasciola hepatica and phylogenetic analysis based on mitochondrial (nicotiamide adenine dinucleotide dehydrogenase subunit I and cytochrome oxidase subunit I) genes from the North-East of Iran

    Science.gov (United States)

    Reaghi, Saber; Haghighi, Ali; Harandi, Majid Fasihi; Spotin, Adel; Arzamani, Kourosh; Rouhani, Soheila

    2016-01-01

    Aim: Fascioliasis is one of the most zoonotic diseases with global extension. As the epidemiological distribution of Fasciola may lead to various genetic patterns of the parasite, the aim of this study is to identify Fasciola hepatica based on spermatogenesis, and phylogenetic analysis using mitochondrial (nicotiamide adenine dinucleotide dehydrogenase subunit I [ND1] and cytochrome oxidase subunit I) gene marker. Materials and Methods: In this study, 90 F. hepatica collected from 30 cattle at slaughterhouse located in three different geographical locations in the North-East of Iran were evaluated based on spermatogenetic ability and internal transcribed spacer 1 gene restriction fragment length polymorphism pattern. Genetic diversity and phylogenetic relationship using mtDNA gene marker for the isolates from the North-East of Iran, and other countries were then analyzed. Results: Partial sequences of mtDNA showed eight haplotypes in both genes. The phylogenic analysis using neighbor joining as well as maximum likelihood methods showed similar topologies of trees. Pairwise fixation index between different F. hepatica populations calculated from the nucleotide data set of ND1 gene are statistically significant and show the genetic difference. Conclusion: F. hepatica found in this region of Iran has different genetic structures through the other Fasciola populations in the world. PMID:27733809

  10. Role of Key Residues at the Flavin Mononucleotide (FMN:Adenylyltransferase Catalytic Site of the Bifunctional Riboflavin Kinase/Flavin Adenine Dinucleotide (FAD  Synthetase from Corynebacterium ammoniagenes

    Directory of Open Access Journals (Sweden)

    Susana Frago

    2012-11-01

    Full Text Available In mammals and in yeast the conversion of Riboflavin (RF into flavin mononucleotide (FMN and flavin adenine dinucleotide (FAD is catalysed by the sequential action of two enzymes: an ATP:riboflavin kinase (RFK and an ATP:FMN adenylyltransferase (FMNAT. However, most prokaryotes depend on a single bifunctional enzyme, FAD synthetase (FADS, which folds into two modules: the C-terminal associated with RFK activity and the N-terminal associated with FMNAT activity. Sequence and structural analysis suggest that the 28-HxGH-31, 123-Gx(D/N-125 and 161-xxSSTxxR-168 motifs from FADS must be involved in ATP stabilisation for the adenylylation of FMN, as well as in FAD stabilisation for FAD phyrophosphorolysis. Mutants were produced at these motifs in the Corynebacterium ammoniagenes FADS (CaFADS. Their effects on the kinetic parameters of CaFADS activities (RFK, FMNAT and FAD pyrophosphorilase, and on substrates and product binding properties indicate that H28, H31, N125 and S164 contribute to the geometry of the catalytically competent complexes at the FMNAT-module of CaFADS.

  11. Molecular Cloning and Sequence Analysis of Adenine Nucleotide Translocase Gene in Antheraea pernyi%柞蚕腺苷酸转移酶基因的克隆与序列分析

    Institute of Scientific and Technical Information of China (English)

    李玉萍; 王欢; 武松; 夏润玺; 刘彦群; 秦利; 李喜升; 姜德富

    2009-01-01

    腺苷酸转移酶(adenine nucleotide translocase,ANT)是线粒体内膜上的转运蛋白家族成员.从柞蚕(An-theraea pernyi)蛹全长cDNA文库中获得了柞蚕腺苷酸转移酶基因(ApANT)的cDNA序列(GenBank登录号FJ788509).对该基因进行生物信息学分析表明:ApANT cDNA全长1 282 bp,含有1个903 bp的开放阅读框(ORF)序列,编码300个氨基酸;ApANT与烟草天蛾(Manduca sexta)等鳞翅目昆虫的ANT基因在核苷酸和氨基酸序列水平分别具有80%和90%以上的同源性,说明ANT蛋白在这些昆虫中是高度保守的;与其它已知鳞翅目昆虫的ANT、蛋白一样,ApANT蛋白含有3个线粒体穿膜结构域,并且这3个保守结构域之间也显示出较高的相似性.

  12. Effects of aqueous extract of Ruta graveolens and its ingredients on cytochrome P450, uridine diphosphate (UDP-glucuronosyltransferase, and reduced nicotinamide adenine dinucleotide (phosphate (NAD(PH-quinone oxidoreductase in mice

    Directory of Open Access Journals (Sweden)

    Yune-Fang Ueng

    2015-09-01

    Full Text Available Ruta graveolens (the common rue has been used for various therapeutic purposes, including relief of rheumatism and treatment of circulatory disorder. To elucidate the effects of rue on main drug-metabolizing enzymes, effects of an aqueous extract of the aerial part of rue and its ingredients on cytochrome P450 (P450/CYP, uridine diphosphate (UDP-glucuronosyltransferase, and reduced nicotinamide adenine dinucleotide (phosphate (NAD(PH:quinone oxidoreductase were studied in C57BL/6JNarl mice. Oral administration of rue extract to males increased hepatic Cyp1a and Cyp2b activities in a dose-dependent manner. Under a 7-day treatment regimen, rue extract (0.5 g/kg induced hepatic Cyp1a and Cyp2b activities and protein levels in males and females. This treatment increased hepatic UDP-glucuronosyltransferase activity only in males. However, NAD(PH:quinone oxidoreductase activity remained unchanged. Based on the contents of rutin and furanocoumarins of mouse dose of rue extract, rutin increased hepatic Cyp1a activity and the mixture of furanocoumarins (Fmix increased Cyp2b activities in males. The mixture of rutin and Fmix increased Cyp1a and Cyp2b activities. These results revealed that rutin and Fmix contributed at least in part to the P450 induction by rue.

  13. Efeito da sacarose, cinetina, isopentenil adenina e zeatina no desenvolvimento de embriões de Heliconia rostrata in vitro Effect of sucrose, kinetin, isopentenyl adenine and zeatin on the development of embryos of Heliconia rostrata in vitro

    Directory of Open Access Journals (Sweden)

    Antonio Carlos Torres

    2005-07-01

    Full Text Available Embriões provenientes de frutos maturos de Heliconia rostrata Ruiz & Pavon foram excisados e inoculados em meio de cultura contendo os sais básicos MS, vitaminas e sacarose. A adição de sacarose foi essencial para o desenvolvimento dos embriões. Em meio desprovido de sacarose os embriões morreram em cultura. Concentrações de 1%, 2% e 3% (p/v de sacarose favoreceram o desenvolvimento dos embriões. Concentrações de 6%, 9% e 12% (p/v de sacarose inibiram o crescimento dos embriões. A adição de cinetina, isopentenil adenina e zeatina não favoreceram o crescimento e o desenvolvimento dos embriões.Embryos from mature fruits of Heliconia rostrata were excised and cultured in basal medium containing MS salts, vitamins and sucrose. Sucrose was essential for embryo development. In meclium without sucrose the embryos died in culture. Sucrose concentrations of 1%, 2% and 3% (w/v were beneficial for embryo development. Sucrose concentrations of 6%, 9% and 12% (w/v inhibited embryo growth. The addition of kinetin, isopentenyl adenine and zeatin did not improve embryo growth and development.

  14. Cloning of Adenine Nucleotide Translocase Gene From Bombyx mori Based on EST Database%利用EST库资源克隆家蚕腺苷酸转移酶基因

    Institute of Scientific and Technical Information of China (English)

    陈大福; 牛宝龙; 翁宏飚; 孟智启; 吕顺霖

    2004-01-01

    根据物种间同源基因相对保守的特点,利用生物信息学方法以果蝇(Drosophila melanogaster)腺苷酸转移酶基因(adenine nucleotide translocase, ant) cDNA序列作为模板,对家蚕(Bombyx mori) EST数据库进行同源检索筛选,克隆了家蚕腺苷酸转移酶基因的cDNA序列(GenBank登录号为AY227000),全长为1 936 bp,并经RT-PCR克隆、序列分析验证,结果与电子克隆序列完全一致.该cDNA序列具有完整的开放阅读框架(ORF, 207~1 109 bp),推测编码蛋白为300个氨基酸,通过与烟草天蛾(Manduca sexta)、蜜蜂(Apis mellifera)、绿蝇(Lucilia cuprina)、果蝇、蚊子(Anopheles gambiae)等昆虫的腺苷酸转移酶蛋白序列比较,发现该基因具有高度的保守性.表明根据物种间同源基因序列,对跨物种间EST数据库进行同源检索筛选、拼接,是基因克隆的一条有效途径.

  15. Applications of adenine nucleotide measurements in oceanography

    Science.gov (United States)

    Holm-Hansen, O.; Hodson, R.; Azam, F.

    1975-01-01

    The methodology involved in nucleotide measurements is outlined, along with data to support the premise that ATP concentrations in microbial cells can be extrapolated to biomass parameters. ATP concentrations in microorganisms and nucleotide analyses are studied.

  16. Second-Generation Fluorescent Quadracyclic Adenine Analogues

    DEFF Research Database (Denmark)

    Dumat, Blaise; Bood, Mattias; Wranne, Moa S.;

    2015-01-01

    Fluorescent base analogues comprise a group of increasingly important molecules for the investigation of nucleic acid structure, dynamics, and interactions with other molecules. Herein, we report on the quantum chemical calculation aided design, synthesis, and characterization of four new putativ...

  17. 益生菌发酵驼乳对慢性肾功能衰竭的治疗作用%The rapeutic Action of Probiotic Fermented Camel Milk on Chronic Renal Failure Rats Caused by Adenine

    Institute of Scientific and Technical Information of China (English)

    李建美; 潘蕾; 张敏; 王娟; 刘薇; 郭春燕; 李擎; 吉日木图

    2011-01-01

    Purpose: To compare the different therapeutic Failure(CRF) of rats. Method: CRF rat models induced by fermentation camel milk. And then evaluated the therapeutic action of probiotics felTnented camel milk on Chronic Renal adenine were received intragastric administration with probiotic effect of three kinds of fermented camel milk by measure the diet and water intake, weight, kidney index, serum creatinine(Scr), Urea Nitrogen(BUN), nitric oxide(NO), superoxide dismutase(SOD), serum total protein(STP), calcium(Ca), phosphorus(P), urine volume in 24 hours, urine protein(UP) and the Renal Biopsy. Result: The result showed that fermentation camel milk can reduce the serum level of Set and BUN, slow down UP, ameliorate the balance of calcium and phosphorus, enhanced the level of SOD and STP and alleviated pathological changes of the kidney tissue. Conclusion: Different kinds of probiotic fermented camel milk are effective in treating CRF of rats and the effect of camel milk fermented by L.casei Zhang is superior to camel milk fermented by other probiotics.%目的:比较不同菌种发酵的驼乳制品对腺嘌呤所致大鼠慢性。肾功能衰竭(CRF)的缓解作用。方法:采用腺嘌呤复制CRF大鼠模型,以不同发酵剂发酵的驼乳作为受试物进行灌胃干预。通过检测大鼠的饮食饮水情况、排尿量、尿液和血清常规指标及肾脏病理组织学变化,评估各发酵驼乳对CRF大鼠的治疗效果。结果:发酵驼乳均可改善肾功能衰竭大鼠的一般生理状况,可降低大鼠血肌酐(Scr)、尿素氦(BUN)水平,减缓尿蛋白(UP),调节Ca、P的含量,提高过氧化物歧化酶(SOD)、血清总蛋白(STP)水平,具有保护肾功能的作用,其中LIcaseiZhang发酵的驼乳对CRF大鼠的改善效果最佳。

  18. Electron Detachment as a Probe of Intrinsic Nucleobase Dynamics in Dianion-Nucleobase Clusters: Photoelectron Spectroscopy of the Platinum II Cyanide Dianion Bound to Uracil, Thymine, Cytosine and Adenine

    Energy Technology Data Exchange (ETDEWEB)

    Sen, Ananya; Hou, Gao-Lei; Wang, Xue B.; Dessent, Caroline

    2015-08-05

    We report the first low-temperature photodetachment photoelectron spectra of isolated gas-phase complexes of the platinum II cyanide dianion bound to nucleobases. These systems are model systems for understanding platinum-complex photodynamic therapies, and knowledge of the intrinsic photodetachment properties is crucial for understanding their broader photophysical properties. Well-resolved, distinct peaks are observed in the spectra consistent with the complexes where the Pt(CN)42- moiety is largely intact. The adiabatic electron detachment energies for the dianion-nucleobase complexes are measured to be between 2.39-2.46 eV. The magnitudes of the repulsive Coulomb barriers of the complexes are estimated to be between 1.9 and 2.1 eV, values that are lower than for the bare Pt(CN)42- dianion as a result of charge solvation by the nucleobases. In addition to the resolved spectral features, broad featureless bands indicative of delayed electron detachment are observed in the 193 nm photodetachment spectra of the four nucleobase-dianion complexes, and also in the 266 nm spectra of the Pt(CN)42-∙thymine and Pt(CN)42-∙adenine complexes. The selective excitation of these features in the 266 nm spectra is attributed to one-photon excitation of [Pt(CN)42-∙T]* and [Pt(CN)42-∙A]* long-lived excited states that can effectively couple to the electron detachment continuum, producing strong electron detachment signals. We attribute the resonant electron detachment bands observed here for Pt(CN)42-∙T and Pt(CN)42-∙A but not for Pt(CN)42-∙U and Pt(CN)42-∙C to fundamental differences in the individual nucleobase photophysics following 266 nm excitation. This indicates that the Pt(CN)42- dianion in the Pt(CN)42-∙M clusters can be viewed as a “dynamic tag” which has the propensity to emit electrons when the attached nucleobase disaplys a long-lived excited state.

  19. Short-hairpin RNA-induced suppression of adenine nucleotide translocase-2 in breast cancer cells restores their susceptibility to TRAIL-induced apoptosis by activating JNK and modulating TRAIL receptor expression

    Directory of Open Access Journals (Sweden)

    Kim Chul-Woo

    2010-09-01

    Full Text Available Abstract Background Tumor necrosis factor (TNF-related apoptosis-inducing ligand (TRAIL; apo2 ligand induces apoptosis in cancer cells but has little effect on normal cells. However, many cancer cell types are resistant to TRAIL-induced apoptosis, limiting the clinical utility of TRAIL as an anti-cancer agent. We previously reported that the suppression of adenine nucleotide translocase-2 (ANT2 by short-hairpin RNA (shRNA induces apoptosis of breast cancer cells, which frequently express high levels of ANT2. In the present study, we examined the effect of RNA shRNA-induced suppression of ANT2 on the resistance of breast cancer cells to TRAIL-induced apoptosis in vitro and in vivo. Results ANT2 shRNA treatment sensitized MCF7, T47 D, and BT474 cells to TRAIL-induced apoptosis by up-regulating the expression of TRAIL death receptors 4 and 5 (DR4 and DR5 and down-regulating the TRAIL decoy receptor 2 (DcR2. In MCF7 cells, ANT2 knockdown activated the stress kinase c-Jun N-terminal kinase (JNK, subsequently stabilizing and increasing the transcriptional activity of p53 by phosphorylating it at Thr81; it also enhanced the expression and activity of DNA methyltransferase 1 (DNMT1. ANT2 shRNA-induced overexpression of DR4/DR5 and TRAIL sensitization were blocked by a p53 inhibitor, suggesting that p53 activation plays an important role in the transcriptional up-regulation of DR4/DR5. However, ANT2 knockdown also up-regulated DR4/DR5 in the p53-mutant cell lines BT474 and T47 D. In MCF7 cells, ANT2 shRNA treatment led to DcR2 promoter methylation and concomitant down-regulation of DcR2 expression, consistent with the observed activation of DNMT1. Treatment of the cells with a demethylating agent or JNK inhibitor prevented the ANT2 shRNA-induced down-regulation of DcR2 and activation of both p53 and DNMT1. In in vivo experiments using nude mice, ANT2 shRNA caused TRAIL-resistant MCF7 xenografts to undergo TRAIL-induced cell death, up-regulated DR4/DR5

  20. 石榴皮鞣质对腺嘌呤性慢性肾衰大鼠保护作用的研究%Protective Effect of Tannin in Punica granatum L.on Chronic Renal Failure in Rats Induced by Adenine

    Institute of Scientific and Technical Information of China (English)

    周本宏; 郭志磊; 王慧媛; 冯琪

    2009-01-01

    目的 观察石榴皮鞣质对腺嘌呤性慢性肾功能衰竭(CRF)大鼠的影响.方法 用250 mg·kg~(-1)腺嘌呤溶液连续灌胃21 d使Wistar大鼠产生类似慢性肾袁的症状.21d后,治疗组大鼠每天用石榴皮鞣质(40,20,10mg·kg~(-1).d~(-1))灌胃,阳性组用20%尿毒清混悬液按2.1 g·kg~(-1)·灌胃.60 d后收集尿液,处死大鼠,取血、留取肾组织,测定血Ca~(2+)、P~(3+)及血肌酐(Scr)、尿素氮(BUN),血脂和24h尿蛋白定量、尿Ca~(2+)、P~(3+),进行统计学处理,并进行形态学观察.结果 石榴皮鞣质对慢性肾衰竭大鼠的血Ca~(2+)、P~(3+)及Scr、BUN和24 h尿蛋白定量、尿Ca~(2+)、P~(3+)有不同程度的改善.结论 石榴皮鞣质对腺嘌呤导致的大鼠慢性肾衰竭有一定的保护作用.%OBJECTIVE To observe the effeets of tannin in Punica granatum L.on chronic renal failure(CRF)in rats induced by adenine.METHODS The Wistar rats were administered intragastrically with adenine(200 mg·kg~(-1)·d~(-1))for 21 d to induce the symptoms similar to chronic renal failure.Then,the rats were administered intragastrically with tannin(40,20 and 10 blood urea nitrogen(BUN),calcium ion(Ca~(2+)),phosphorus ion(P~(3+)),blood lipids and urine protein of 24 h were determined and analyzed.Meanwhile morphology was observed.RESULTS Serum levels of Scr,BUN and P~(3+) were decreased but Ca~(2+) level was increased by tannin in Punica granatum L.CONCLUSION Tannin in Punica granatum L can improve the renal function injuried by metabolic products in adenine-modeled CRF rats.

  1. 斑节对虾腺苷酸转移酶(PmANT)基因的cDNA克隆与表达分析%Molecular cloning and expression analysis of adenine nucleotide translocase (PmANT) in Penaeus monodon

    Institute of Scientific and Technical Information of China (English)

    孙文文; 周发林; 黄建华; 邱丽华; 杨其彬; 江世贵

    2013-01-01

    利用RACE技术获得了斑节对虾(Penaeus monodon)ANT基因(PmANT)的cDNA序列.该序列全长1 388 bp,开放阅读框(ORF)为930 bp,3’非编码区(UTR)为393 bp,5 '非编码区(UTR)为65 bp.ORF可编码309个氨基酸,分子量大约为33.622 ku.与所有ANT家族成员一样,PmANT蛋白具有3个重复同源的线粒体跨膜结构域,但不含信号肽和糖基化位点.相似性、同源性及系统进化树分析显示,斑节对虾的ANT基因与凡纳滨对虾的同源性和相似性最高,并与其聚为一支.采用荧光定量的方法研究了ANT基因在雌雄个体不同组织、卵巢不同发育阶段及未成熟和成熟精巢的差异表达情况.结果表明:PmANT的mRNA在各组织中都有表达,其中,在雄性个体的肌肉中表达量最高,其次为雌性肌肉,在精巢的表达量最低,且未成熟精巢低于成熟精巢.PmANT的mRNA在卵巢的表达量高于精巢,且在Ⅲ期卵巢表达量最高,Ⅳ期最低.为今后进一步研究该基因在斑节对虾性腺发育中的作用提供基础材料.%The adenine nucleotide translocase (ANT) is the most abundant mitochondrial inner membrane protein, which catalyzes the exchange of ADP and ATP between cytosol and mitochondria and participates in many models of mitochondrial apoptosis. In the present study, the full sequence of P. Monodon ANT gene was cloned and named PmANT. The full length cDNA of PmANT contained a 5' untranslated region (UTR) of 65 bp, a 3' UTR of 393 bp and an ORF of 930 bp encoding a polypeptide of 309 amino acids with an estimated molecular mass of 33. 622 ku. Like other animal ANTs, the structure of the PmANT protein consists of three homologous repeated domains. But there are no signal peptide and glycosylation sites in PmANT protein. Sequence alignment analysis showed that the PmANT with the ANT of Litopenaeus vannamei shared a similarity of 98. 7% and the homology of 97. 4%. Analysis of the tissue expression pattern of the PmANT showed that the PmANT m

  2. RNA aptamers for an essential prebiotic molecule: adenine

    Science.gov (United States)

    Meli, M.; Vergne, J.; Josse, T.; Décout, J.-L.; Maurel, M.-C.

    2001-08-01

    Among all known bio-organic molecules within the living cells, RNA molecules are the only ones storing genetic information and performing catalysis. The RNA world hypthesis assumes that livings on earth are derived from an RNA molecular ancestor where RNA both stored the genetic information and catalyzed the first metabolic reactions. Among diverse RNA worlds proposed, it is thought that the invention of translation and encoded peptide synthesis took place with a "breakthrough organism", then giving rise to a ribonucleoprotein (RNP) world. Finally, modern biochemistry arose with the invention of DNA and the birth of modern molecular biology where the information flows from DNA to RNA which directs protein synthesis. Considering modern metabolism, it is possible to assign biochemical traits to the last common ancestor by simple parsimony rules, and assumptions about earlier metabolisms are possible using chemical criteria. According to this point of view, modern metabolism is considered as a palimpsest that has to be read and deciphered in ordered to understand its origin and evolution.

  3. 升清降浊胶囊对腺嘌呤所致大鼠肾性贫血肾组织TNF-α表达的影响%Influence of Shengqing Jiangzhuo Capsule on Expression of TNF-α in Rat Renal Tissue with Adenine-induced Anemia

    Institute of Scientific and Technical Information of China (English)

    宋丽; 桑志强; 张慧; 金礼; 刘禹; 聂子牧; 姬赐祥; 刘韬; 童安荣

    2012-01-01

    Objective To explore the influence of Shengqing Jiangzhuo capsule on expression of TNF - α in rat renal tissue with adenine - indeced anemia. Methods The chronic anemia model was established by adenine intragastrically in SD rats. According to the weight rats were divided into six groups: normal control group, model control group , high Shengqingjiangzhuo capsule group, middle concentration group, low concentration group and Shenshuaining Capsule control group. After four and six weeks with treatment, blood red blood cells ( RBC ) , the hemoglobin ( HGB ) , aspartate transaminase ( AST ) , alanine aminotransferase (ALT) , creatinine (Scr) , blood urea nitrogen (BUN) were determined and observed. The renal pathology change were observed using HE dyeing. TNF alpha expression was monitored with immunohistochemistry methods in kidney tissues. Results After 4 weeks and six weeks of treatment, RBC, HGB were reduced significantly and Scr, BUN were elevated significantly (P <0. 05 ) . TNF alpha positive expression rate increased significantly in model control group compared with normal control group (P <0.05). RBC, HGB in Shenshuaining group and Shengqingjiangzhuo capsule groups were significantly higher , than those in model group (P<0.05 ). Scr, BUN in Shenshuaining group and Shengqingjiangzhuo capsule groups were significantly lower than those in model group ( P < 0. 05 ) . The TNF alpha positive expression rate in Shenshuaining group and Shengqingjiangzhuo capsule groups was significantly lower than that in model group (P <0. 05) . Conclusion Shengqing Jiangzhuo capsule may increase generation of the red blood cells by clearing urine toxins, reducing the inflammatory cells infiltration and restraining TNF alpha in the expression of the kidney tissues. It plays an active role in the treatment of renal anemia.%目的 观察升清降浊胶囊对腺嘌呤所致慢性贫血大鼠TNF-α表达的影响,探讨升清降浊胶囊治疗贫血的作用机制.方法 采用腺嘌

  4. Synthesis and Biological Evaluation of Nicotinamide Adenine Dinucleotides Analogues as Inhibitors of CD38%烟酰胺腺嘌呤二核苷酸类CD38抑制剂的合成及生物活性评价

    Institute of Scientific and Technical Information of China (English)

    陈哲; KWONGAnnaKa-Yee; 杨振军; 张亮仁; LEEHonCheung; 张礼和

    2012-01-01

    CD38 is the main mammalian ADP-ribosyl cyclase and a signaling enzyme responsible for catalyzing the synthesis of Ca2+-messengers and plays a critical role in a wide range of physiological functions. It is of great interest to develop specific and generally applicable inhibitors of CD38. Fluoro-substituted nicotina-mide adenine dinucleotides( NAD) , such as ara-F NMN and ara-F NAD, are catalysis-dependent inhibitors of CD38 and are often used as probes for investigating the function of CD38. For understanding the effect of fluo-ro-substitution on activity in more detail and discovery of active inhibitors of CD38, compounds 2a-2c were synthesized and their inhibition against the hydrolysis activities of CD38 were evaluated. The syntheses were performed by starting from the corresponding fluoro-substituted sugar, then followed by coupling with nicoti-namide, regio-seleclive 5 '-phosphorylation and condensation with adenosine monophosphate, successively. All target compounds were purified by HPLC and characterized by NMR and HRMS. Two compounds showed strong inhibitions, especially 2'-deoxy-2'-fluororibonofuranosyl which gave activity with IC50 of 0. 056μmol/L and was two orders of magnitude higher than positive control ara-F NAD. The results also showed that the activity was greatly affected by the number and the position of fluorine atom on the sugar ring, as well as the configuration of the inhibitors. The detailed biological investigation and structure-activity relationship are underway.%分别以1,3,5-三苯甲酰基-α-D-核糖、3,5-二苯甲酰基-2-脱氧-2,2-氟戊呋喃糖-1-酮和D-木糖为原料,经由烟酰胺核苷及烟酰胺核苷酸中间体,合成了系列糖环经氟原子取代的烟酰胺腺嘌呤二核苷酸(NAD)类CD38抑制剂.基于对CD38的水解抑制能力的考察,评价了所合成氟代NAD类似物的活性.结果表明,糖环上氟原子取代的数目和位置对抑制剂活性的影响十分明显,烟酰胺核苷的端

  5. Study on the Inclusion Interactions of Cucurbit[7]uril with 6-Mercaptopurine and Adenine by Fluorescence Spectrometric Method%荧光光谱法研究葫芦[7]脲与6-巯嘌呤和腺嘌呤的包结作用

    Institute of Scientific and Technical Information of China (English)

    何小英; 李来生; 方奕珊; 陈红

    2012-01-01

    The inclusion interactions of cucurbit [7] uril (CB[7]) with 6-mercaptopurine (6-MP) and adenine(ADP) were studied by fluorescence spectrometric method. Several effect factors such as time, the pH value and temperature on the fluorescence intensity and the stability of the complex were investigated. The complex constants of CB[7] with 6-MP and ADP were determined according to the Benesi-Hildebrand equation,respectively. The results indicated that the pH value had a significant effect on the inclusion interactions. 6-MP and ADP had the optimal and stable excitation and emission wavelength as the pH value were 8. 0 for 6-MP and 2. 0 for ADP within 5 min. With the increasing of the concentrations of CB[7],the fluorescence of the two complexes increased obviously. The inclusion constants were 3. 6797× 102 L·mol-1 for 6-MP-CB[7] and 2. 2033 × 102 L·mol-1 for ADP-CB[7] at 298 K with the same inclusive ratio of It 1. The main interaction forces between CB[7] and the above purines were discussed based on the thermodynamic parameters. CB[7] is only well water-soluble superamolecules among cucurbituril family members, and has great potential as drug carriers with safety and low toxicity.%采用荧光光谱法分别研究了葫芦[7]脲(CB[7])对6-巯嘌呤(6-MP)和腺嘌呤(ADP)的包结作用.实验考察了时间、pH值以及温度对荧光强度和包结作用的影响,利用Benesi-Hildebrand方程分别计算出6-MP和ADP与CB[7]的包结常数.结果表明:酸度对体系的包结有明显的影响.在pH值为8.0和2.0左右时,6-MP和ADP分别具有稳定和最佳激发和发射波长,随着CB[7]浓度的增大,体系的荧光强度都有明显增强,包结作用迅速(小于5 min).实验得出CB[7]与6-MP和ADP的包结比均为1∶1,在298 K时的包结常数分别为3.6797×102 L·mol-1和2.2033×102 L·mo1-1.通过热力学参数的变化,探讨了维系包结物稳定性的主要作用力.CB[7]是葫芦脲家族中水溶性最强的主体分子,作为一种

  6. Adenine translocase 1gene transfection induces apoptosis of vascular smooth muscle cells in rats with carotid balloon injury%转染ANT1基因诱导颈动脉球囊损伤大鼠血管平滑肌细胞凋亡

    Institute of Scientific and Technical Information of China (English)

    杨易; 李燕; 王霄; 刘洁; 卢巍; 宋耀明

    2012-01-01

    Objective To study the effect of adenine nucleotide translocase 1 (ANT1) gene over-expression on apoptosis of vascular smooth muscle cells ( VSMC ) in a rat carotid balloon injury model induced by adenovirus plasmid. Methods Seventy-two SD rats were randomly divided into normal group, non-transfection group, Ad-GFP transfection group and Ad-ANTl transfection group (18 in each group). ANT1 gene was trans-fected into rat carotid arteries with Ad-ANTl adenovirus after a rat carotid balloon injury model was established. The arteries were harvested on days 7, 14 and 28 after operation. Expression of ANT-1, BAX, and Bcl-2 in arteries was detected by RT-PCR, Western blotting, and immunohistochemistry, respectively, with HE staining. Apoptosis of VSMC in tunica intima and tunica media of the model was assayed with TUNEL staining. Results The ANT1 gene was significantly expressed in rat carotid arteries after Ad-ANTl transfection and reached its peak level on day 14, which was significantly higher in Ad-ANTl transfection group than in Ad-GFP transfection group and balloon injury group (P 0. 05). The apoptosis rate of VSMC in tunica intima and tunica media of the model was significantly higher in Ad-ANTl transfection group than in the other 3 groups (P <0. 05). The tunica intima/ tunica media area ratio in the model was lower in Ad-ANTl transfection group than in Ad-GFP transfection group and balloon injury group on days 14 and 28 after transfection(P<0. 05). Conclusion Adenovirus plasmid-induced over-expression of ANT1 gene induces apoptosis of VSMC in tunica intima/ tunica media of the model by up-regulating the expression of BAX.%目的 通过腺病毒载体在体转染大鼠颈总动脉球囊损伤模型,研究过表达腺嘌呤核苷酸转位酶-1( adeninenucleotide translocase 1,ANT1)对血管平滑肌细胞凋亡的影响.方法 将72只雄性SD大鼠随机分为正常组、单纯损伤组、Ad-GFP转染组、Ad-ANT1转染组,每组18只.用携带ANT1

  7. 拟穴青蟹ANT2基因在不同温度和盐度条件下的应激表达%Effects of different temperature and salinity on the expression of ade-nine nucleotide translocase 2 (ANT2) mRNA in the mud crab, Scylla paramamosain

    Institute of Scientific and Technical Information of China (English)

    于坤; 叶海辉; 黄陈翠; 巩杰; 黄辉洋

    2014-01-01

    采用qRT-PCR技术,对不同温度(10℃,15℃,20℃,25℃)以及低温(10℃,15℃)和盐度(10,35)联合作用下拟穴青蟹(Scylla paramamosain)(甲壳长3.7~5.8 cm,体质量80~100 g) ANT2基因的表达进行了检测。结果表明:在4个温度下肝胰腺、肌肉、鳃中 ANT2基因表达量依次为低、中、高,存在组织表达特异性。随着温度降低, ANT2基因总体上趋低表达,但在15℃时ANT2基因在肌肉(1~12 h)和鳃中均显著高于20℃( P<0.05)。该结果提示, ANT2基因与能量代谢相关,且在一定低温下被诱导表达,可能参与低温胁迫的应答。相同低温下,3种组织中ANT2基因在盐度10的表达量通常高于盐度35的(P<0.05),说明低温下低盐环境有利于提高青蟹体内代谢,增强耐寒能力。%The mud crab Scylla paramamosain, a eurythermal and euryhaline species, is a commercially exploited crab inhabiting the southeastern coast of China. In recent years, mud crab aquaculture has suffered as a result of unsettled weather, which has led to a seasonal temperature and salinity changes in the sea water. This study aims to explore the molecular mechanism of cold tolerance in S. paramamosain by examining the expression of adenine nucleotide trans-locase 2 (ANT2) at different temperatures and salinities. ANT belongs to the mitochondrial carrier superfamily (MCF). It is the most abundant inner membrane protein of the mitochondrion and is responsible for the transport of ADP and ATP in the cytoplasm and mitochondrial matrix through the inner mitochondrial membrane. In this study, the relative expression of ANT2 mRNA was detected using real-time quantitative polymerase chain reaction at different tempera-tures (10℃, 15℃, 20℃, 25℃), and low temperatures (10℃, 15℃) combined with salinity (10, 35) in mud crabs (cara-pace width 3.7–5.8 cm, body weight 80–100 g). Real-time qPCR indicated that, at different temperatures, ANT2 was expressed in the hepatopancreas, muscle and

  8. 尼克酰胺腺嘌呤二核苷酸磷酸氧化酶4源性活性氧过量产生抑制胚胎干细胞向心肌细胞的分化%Excessive production of nicotinamide adenine dinucleotide phosphate oxidase 4-dependent reactive oxygen species suppresses cardiomyocyte differentiation from embrvonic stem cells

    Institute of Scientific and Technical Information of China (English)

    张小勇; 国汉邦; 黎健

    2007-01-01

    二核苷酸磷酸氧化酶4过表达诱导的细胞凋亡.结果:①不同水平的活性氧对心肌细胞分化具有不同的效应.在分化后4 d用较低浓度(1~100 nmol/L)的过氧化氢处理胚小体2 h可明显促进心肌细胞分化(P<0.01),而较高浓度(> 1 μmol/L)的过氧化氢则显示出抑制作用(P<0.01).②尼克酰胺腺嘌呤二核苷酸磷酸氧化酶4程小鼠胚胎干细胞中的表达水平最高,尼克酰胺腺嘌呤二核苷酸磷酸氧化酶3虽然也在胚胎干细胞中表达,但表达水平低,丽尼克酰胺腺嘌呤二核苷酸磷酸氧化酶1、2在胚胎干细胞中不表达.RT-PCR检测结果显示,与单纯转染pcDNA3.1细胞相比,转染pcDNA3.1-NOX4质粒的CGR8细胞中尼克酰胺腺嘌呤二核苷酸磷酸氧化酶4过表达.③四唑氮蓝实验检测结果显示,高水平表达的尼克酰胺腺嘌呤二核苷酸磷酸氧化酶4引起过量活性氧产生(P<0.05).与未转染质粒的细胞相比,尼克酰胺腺嘌呤二核苷酸磷酸氧化酶4过表达抑制了心肌细胞的分化(P<0.01). Western Blot结果显示高水平尼克酰胺腺嘌呤二核苷酸磷酸氧化酶4导致胚小体内MLC2v蛋白水平降低.④p21和p53可能参与了NADPH氧化酶4诱导的凋亡过程.转染尼克酰胺腺嘌呤二核苷酸磷酸氧化酶4的p53-/-ES细胞R72D27并未发生凋亡,高水平的Bcl-2可以抑制尼克酰胺腺嘌呤二核苷酸磷酸氧化酶4过表达诱导的细胞凋亡.结论:尼克酰胺腺嘌呤二核苷酸磷酸氧化酶4在心肌细胞分化中起关键作用,p53和p21以及Bcl-2可能参与了凋亡信号通路的调控.%BACKGROUND: Reactive oxygen species (ROS), including superoxide anion (O2) and hydrogen peroxide (H2O2), have been recognized as specific second messengers in signaling cascades involved in the growth and differentiation of cells.The generation of excessive ROS initiates cardiomyocyte apoptosis. This paper is aimed to corroborate the hypothesis that excessive amounts of nicotinamide adenine

  9. 不同糖耐量人群血清吞噬细胞样还原型烟酰胺腺嘌呤二核苷酸磷酸氧化酶水平与胰岛β细胞功能的关系%Relationship between serum level of phagocyte-like nicotinamide adenine dinucleotide phosphate oxidase and pancreaticβ-cell function among different groups of glucose tolerance

    Institute of Scientific and Technical Information of China (English)

    陈鹤文; 吴垣辕; 田晶; 贾方; 刘东方

    2015-01-01

    Objective To evaluate the oxidative status under different blood glucose levels, and study the relationship between body phagocyte-like nicotinamide adenine dinucleotide phosphate oxidase (Nox) with oxidative stress and pancreaticβ-cell function. Methods According to the fasting blood-glucose and oral glucose tolerance test,84 individuals who participated physical exam were divided into 3 groups:normal glucose tolerance group(NGT,n=26, FPG<6.1 mmol/L and OGTT 2 hPG<7.8 mmol/L), impaired glucose regulation group (IGR, n=27, FPG between 6.1-7.0 mmol/L and OGTT 2 hPG<7.8 mmol/L)or FPG<6.1 mmol/L and OGTT 2 h PG between 7.8-11.1 mmol/L,or FPG between 6.1-7.0 mmol/L and OGTT 2 h PG between 7.8-11.1 mmol/L, and diabetes mellitus group(n=31, FPG≥7.0 mmol/L ,and/or OGTT 2 hPG≥11.1 mmol/L).Nox, 8-hydroxy-2′-deoxyguanosine (8-OHdG), superoxide dismutase(SOD), malondialdehyde( MDA) was measured. The islet beta cell function index(HBCI)was calculated by each recognized formula. Variance analysis was used to analysis between multiple groups,and independent samples t testto comparetwo groups. Pearson′s correlation Multivariate regression analysis were performed between HBCI which was corrected by insulin resistance and other variable. Results With the increase of blood glucose, the level of Nox in DMgroup was higher than IGR group.HBCI was decreased((143.3±22.1)vs(118.0±21.8)U/L, (12.4 ± 2.3)vs(31.1 ± 7.7), t=2.156,5.621, respectively,all P<0.05). Nox in DM group was significantly higher than NGT,group. HBCI was significantly decreased((143.3 ± 22.1)vs (97.2 ± 19.9)U/L,12.4 ± 2.3 vs 105.2±21.3, t=4.460,4.111, respectively,all P<0.05). The further multiple regression analysis indicated that only Nox was independent factor on HBCI(r=-0.572,β=-1.088, R2=0.455,P<0.001). Conclusions Nox maybe an ideal index in reflecting the oxidative status in the body. Oxidative stress derived from Nox is closely tied to pancreaticβ-cell function.%目的:研究不同血糖水

  10. The Effect of Solvation on the Radiation Damage Rate Constants for Adenine

    DEFF Research Database (Denmark)

    Milhøj, Birgitte Olai; Sauer, Stephan P. A.

    2016-01-01

    It is a well known fact, that water plays an important part in almost all biological systems and that inclusion of solvation effects might therefore be of utmost importance in studies of radiation damage to DNA. In the present investigation we have studied the effect of different solvation models...

  11. Enhanced shoot multiplication in Ficus religiosa L. in the presence of adenine sulphate, glutamine and phloroglucinol.

    Science.gov (United States)

    Siwach, Priyanka; Gill, Anita Rani

    2011-07-01

    Ficus religiosa (Pipal) is a long-lived valuable multipurpose forest tree. The tree is exploited because of its religious, ornamental and medicinal value and the regeneration rate in natural habitat is low. An in vitro propagation protocol has been developed from nodal segments obtained from a 45-50-year old tree. The highest bud break frequency (100 %) followed by maximum number of multiple shoots (13.9) as well as length (2.47 cm) were obtained on Woody Plant medium (WPM) supplemented with 1.0 mg/l BAP along with 0.5 mg/l IAA. Two modifications in this medium resulted in enhanced shoot regeneration-one with 200 mg/l glutamine + 150 mg/l ADS (called as MM-1) giving 32.5 shoots per nodal explant while another modification-with 200 mg/l glutamine + 150 mg/l ADS + 100 mg/l phloroglucinol (called as MM-2) giving 35.65 shoots per explant. These two media were used for sub-culturing of shoots for 4 months. The rate of shoot multiplication was same during the first three sub-cultures on MM-1 and the shoots regenerated were healthy, afterwards shoot multiplication declined. While on MM-2, shoot multiplication declined after first sub-culture and shoots underwent the problem of early leaf fall. Rooting was best induced in micro-shoots excised from proliferated shoot cultures on semi-solid as well as liquid WPM modified with 2.0 mg/l IBA and 0.5 mg/l IAA. The in vitro-raised plantlets were potted and acclimatized under culture room conditions for 25-30 days before transfer to soil conditions, where the established plants showed more than 90 % survival. PMID:23573019

  12. Wolbachia prophage DNA adenine methyltransferase genes in different Drosophila-Wolbachia associations

    DEFF Research Database (Denmark)

    Saridaki, Aggeliki; Sapountzis, Panagiotis; Harris, Harriet L;

    2011-01-01

    Wolbachia is an obligatory intracellular bacterium which often manipulates the reproduction of its insect and isopod hosts. In contrast, Wolbachia is an essential symbiont in filarial nematodes. Lately, Wolbachia has been implicated in genomic imprinting of host DNA through cytosine methylation. ...

  13. A Human Mitochondrial Transcription Factor Is Related to RNA Adenine Methyltransferases and Binds S-Adenosylmethionine

    OpenAIRE

    McCulloch, Vicki; Seidel-Rogol, Bonnie L.; Shadel, Gerald S.

    2002-01-01

    A critical step toward understanding mitochondrial genetics and its impact on human disease is to identify and characterize the full complement of nucleus-encoded factors required for mitochondrial gene expression and mitochondrial DNA (mtDNA) replication. Two factors required for transcription initiation from a human mitochondrial promoter are h-mtRNA polymerase and the DNA binding transcription factor, h-mtTFA. However, based on studies in model systems, the existence of a second human mito...

  14. Inactivation of yeast alcohol dehydrogenase by alkylperoxyl radicals. Characteristics and influence of nicotinamide-adenine dinucleotides.

    Science.gov (United States)

    Videla, L A; Salim-Hanna, M; Lissi, E A

    1992-10-01

    The study of the interaction of alkylperoxyl radicals generated by the aerobic thermolysis of 2,2'-azobis(2-amidinopropane) (AAP) with yeast alcohol dehydrogenase (YADH) revealed a high reactivity of the enzyme, with an average of about 20 radicals per added YADH tetramer being needed to elicit its total inactivation. NAD+ enhanced YADH inactivation at NAD+/YADH molar ratios from 0.25 to 1, decreasing the rate of the process when added in excess to the enzyme concentration. At NADH/YADH molar ratios greater than 1, NADH exhibited a protective effect characterized by a poorly defined induction time and lower inactivation rates, which progressively increased during the reaction period. These changes occurred concomitantly with the oxidation of NADH into NAD+, which might counteract the protective effect of NADH. Under similar conditions, NADP+ did not modify AAP-induced YADH inactivation, while NADPH exhibited a modest protection at NADPH/YADH molar ratios greater than 1. It is concluded that YADH inactivation by alkylperoxyl radicals is strongly dependent on the redox state of the NADH-NAD+ couple, as the rates of the process at different time intervals inversely correlate with the respective NADH/NAD+ ratios.

  15. Synthesis and Characterization of Oligodeoxyribonucleotides Modified with 2'-Amino-α-l-LNA Adenine Monomers

    DEFF Research Database (Denmark)

    Andersen, Nicolai K; Anderson, Brooke A; Wengel, Jesper;

    2013-01-01

    The development of conformationally restricted nucleotide building blocks continues to attract considerable interest because of their successful use within antisense, antigene, and other gene-targeting strategies. Locked nucleic acid (LNA) and its diastereomer α-l-LNA are two interesting examples...

  16. Activities of adenine nucleotide and nucleoside degradation enzymes in platelets of rats infected by Trypanosoma evansi.

    Science.gov (United States)

    Oliveira, Camila B; Da Silva, Aleksandro S; Vargas, Lara B; Bitencourt, Paula E R; Souza, Viviane C G; Costa, Marcio M; Leal, Claudio A M; Moretto, Maria B; Leal, Daniela B R; Lopes, Sonia T A; Monteiro, Silvia G

    2011-05-31

    Nucleotide and nucleoside-degrading enzymes, such as nucleoside triphosphate diphosphohydrose (NTPDase), 5'-nucleotidase and adenosine deaminase (ADA) are present in the surface membranes of platelets, involved in clotting disturbances of Trypanosoma evansi-infected animals. Thus, this study was aimed at evaluating the activities of these enzymes in platelets of rats experimentally infected with T. evansi. Animals were divided into four groups, according to the level of parasitemia. Blood samples were collected on days 3 (group A: at the beginning of parasitemia), 5 (group B: high parasitemia) and 15 (group C: chronic infection), post-infection. Group D (control group) was composed of non-infected animals for platelet count, separation and enzymatic assays. Animals from groups A and B showed marked thrombocytopenia, but platelet count was not affected in chronically infected rats. NTPDase, 5'-nucleotidase and ADA activities decreased (pplatelets from rats of groups A and B, when compared to the control group. In group C, only NTPDase and 5'-nucleoside activities decreased (pplatelet count and nucleotide/nucleoside hydrolysis were positive and statistically significant (pPlatelet aggregation was decreased in all infected groups, in comparison to the control group (pplatelets of T. evansi-infected animals might be related to thrombocytopenia, that by reducing the number of platelets, there was less release of ATP and ADP. Another possibility being suggested is that changes have occurred in the membrane of these cells, decreasing the expression of these enzymes in the cell membrane.

  17. X-ray crystal structure of N-6 adenine deoxyribose nucleic acid methyltransferase from Streptococcus pneumoniae

    Science.gov (United States)

    Tran, Phidung Hong

    X-ray diffraction by using resonant anomalous scattering has become a popular tool for solving crystal structures in the last ten years with the expanded availability of tunable synchrotron radiation for protein crystallography. Mercury atoms were used for phasing. The crystal structure of N-6 deoxyribose nucleic acid methyltransferase from Streptoccocus pneumoniae (DpnM) was solved by using the Multiple Anomalous Diffraction technique. The crystal structure reveals the formation of mercaptide between the mercury ion and the thiol group on the cysteine amino acid in a hydrophobic environment. The crystal structure contains the bound ligand, S- adenosyl-l-methionine on the surface of the concave opening. The direction of the β-strands on the beta sheets are identical to other solved methyltransferases. The highly conserved motifs, DPPY and the FxGxG, are found to be important in ligand binding and possibly in methyl group transfer. The structure has a concave cleft with an opening on the order of 30 Å that can accommodate a DNA duplex. By molecular modelling coupled to sequence alignment, two other highly conserved residues Arg21 and Gly19 are found to be important in catalysis.

  18. Scanning tunneling microscopy theory for an adsorbate: Application to adenine adsorbed on a graphite surface

    OpenAIRE

    Ou-Yang, Hui; Marcus, R. A.; Källebring, Bruno

    1994-01-01

    An expression is obtained for the current in scanning tunneling microscopy (STM) for a single adsorbate molecule. For this purpose the ``Newns–Anderson'' treatment (a ``discrete state in a continuum'' treatment) is used to obtain wave functions and other properties of the adsorbate/substrate system. The current is expressed in terms of the adsorbate–tip matrix elements, and an effective local density of states of the adsorbate/substrate system, at the adsorbate. As an example, the treatment i...

  19. Caffeic acid treatment alters the extracellular adenine nucleotide hydrolysis in platelets and lymphocytes of adult rats.

    Science.gov (United States)

    Anwar, Javed; Spanevello, Roselia Maria; Pimentel, Victor Camera; Gutierres, Jessié; Thomé, Gustavo; Cardoso, Andreia; Zanini, Daniela; Martins, Caroline; Palma, Heloisa Einloft; Bagatini, Margarete Dulce; Baldissarelli, Jucimara; Schmatz, Roberta; Leal, Cláudio Alberto Martins; da Costa, Pauline; Morsch, Vera Maria; Schetinger, Maria Rosa Chitolina

    2013-06-01

    This study evaluated the effects of caffeic acid on ectonucleotidase activities such as NTPDase (nucleoside triphosphate diphosphohydrolase), Ecto-NPP (nucleotide pyrophosphatase/phosphodiesterase), 5'-nucleotidase and adenosine deaminase (ADA) in platelets and lymphocytes of rats, as well as in the profile of platelet aggregation. Animals were divided into five groups: I (control); II (oil); III (caffeic acid 10 mg/kg); IV (caffeic acid 50 mg/kg); and V (caffeic acid 100 mg/kg). Animals were treated with caffeic acid diluted in oil for 30 days. In platelets, caffeic acid decreased the ATP hydrolysis and increased ADP hydrolysis in groups III, IV and V when compared to control (P<0.05). The 5'-nucleotidase activity was decreased, while E-NPP and ADA activities were increased in platelets of rats of groups III, IV and V (P<0.05). Caffeic acid reduced significantly the platelet aggregation in the animals of groups III, IV and V in relation to group I (P<0.05). In lymphocytes, the NTPDase and ADA activities were increased in all groups treated with caffeic acid when compared to control (P<0.05). These findings demonstrated that the enzymes were altered in tissues by caffeic acid and this compound decreased the platelet aggregation suggesting that caffeic acid should be considered a potentially therapeutic agent in disorders related to the purinergic system.

  20. Drug Release Properties of a Series of Adenine-Based Metal-Organic Frameworks.

    Science.gov (United States)

    Oh, Hyojae; Li, Tao; An, Jihyun

    2015-11-16

    The drug uptake and release properties of a series of biomolecule-based metal-organic frameworks (bMOF-1, bMOF-4, bMOF-100, and bMOF-102) have been studied. The bMOFs were loaded with the small molecule etilefrine hydrochloride and release profiles were collected in both Nanopure water and simulated body fluid (SBF). Each bMOF exhibited an initial burst of drug release at the initial stages of the experiment followed by a gradual release of the remaining drug molecules over time. bMOF-1 released 50% of the drug after 15 days and complete release at 80 days in SBF. bMOF-4 released 50% of the drug within two days and complete release at 49 days in SBF. bMOF-100 and bMOF-102 released 50% of the drug after 4 h and complete release at 69 and 54 days in SBF, respectively.

  1. Handle region peptide and losartan decreasing the expression of subunits of nicotinamide adenine dinucleotide phosphate oxidase in celiac adipose tissue in rats neonatally treated with sodium L-glutamate%手把区域多肽及氯沙坦抑制左旋谷氨酸钠大鼠腹部脂肪组织还原型烟酰胺腺嘌呤二核苷酸磷酸氧化酶亚单位的表达

    Institute of Scientific and Technical Information of China (English)

    鄞国书; 徐冬川; 孙如琼; 林少达

    2014-01-01

    Objective To investigate the effect of handle region peptide (HRP) on insulin sensitivity,local renin-angiotensin system and subunits of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase in abdominal adipose tissue in the rats neonatally treated with monosodium L-glutamate (MSG).Methods The eight-week-old MSG rats were randomly divided into MSG control group (MSG group,n =6),HRP treated group (MSG-HRP group,n =6,1.0 mg · d-1 · kg-1 with mini-pump),losartan treated group (MSG-L group,n =6,450 mg/L in drinking water) and HRP with losartan combined treated group (MSG-HRP-L group,n =6).The period of treatment is four weeks.Normal SD rats (con group,n =6) served as control.At the age of 12 weeks,insulin tolerance test was performed to evaluate the insulin sensitivity.The blood glucose ratio of 30 min to 0 min after infusion of insulin was calculated.The mRNA levels of (Pro) renin,(Pro) renin receptor ((P) RR),angiotensin type 1 receptor (AT1R) and subunits of NADPH oxidase,including p47phox and p22phox in abdominal adipose tissue were measured by realtime PCR,and the protein level of angiotensin-Ⅱ (Ang-Ⅱ) was measured by ELISA.ANOVA and LSDtest was performed to estimate difference between groups.Results The ratio of blood glucose concentration 30 min after insulin injection to the basic blood glucose concentration was calculated.The MSG group (92%± 12%) had the highest level of the ratio and had statistic difference with the Con group (66% 8%),MSG-HRP group (76% ±5%),MSG-L group (78% ±5%) and MSG-HRP-L group (75% 10%) (F =6.875,all above P < 0.05).The (pro) renin mRNA was not detected in abdominal adipose tissue.The MSG-HRP group,MSG-L group,and MSG-HRP-L group had 1.92,3.19 and 1.90 times (F=9.805,all P < 0.05) of (P) RR mRNA expression respectively and had 72%,45%,and 53% (F =14.508,all P <0.05) of AT1R mRNA expression respectively compared to the MSG group.Compared to the MSG group ((56 ± 4) ng/g protein

  2. Mechanisms of Berberine (Natural Yellow 18)–Induced Mitochondrial Dysfunction: Interaction with the Adenine Nucleotide Translocator

    OpenAIRE

    Pereira, Cláudia V.; Machado, Nuno G; Oliveira, Paulo J

    2008-01-01

    Berberine [Natural Yellow 18, 5,6-dihydro-9,10-dimethoxybenzo(g)-1,3-benzodioxolo (5,6-a) quinolizinium] is an alkaloid present in plants of the Berberidaceae family and used in traditional Chinese and North American medicine. We have previously demonstrated that berberine causes mitochondrial depolarization and fragmentation, with simultaneous increase in oxidative stress. We also demonstrated that berberine causes an inhibition of mitochondrial respiration and a decrease on calcium loading ...

  3. Responses of corn root protoplasts to exogenous reduced nicotinamide adenine dinucleotide: Oxygen consumption, ion uptake, and membrane potential

    OpenAIRE

    Lin, Willy

    1982-01-01

    Addition of 1.5 mM NADH tripled the O2 consumption in corn root protoplasts. The stimulation was temperature and pH dependent, specific to NADH, and accompanied by a 2- to 3-fold increase in K+ and Pi uptake into protoplasts. The increase in ion uptake was not due to the accumulation of NADH into protoplasts. The effect of exogenous NADH on O2 consumption and ion uptake was also evident in corn root segments but to a lesser extent. A 20-mV hyperpolarization of protoplast membrane potential oc...

  4. The Nicotinamide Adenine Dinucleotide Phosphate Oxidase Homologues NOX1 and NOX2/gp91phox Mediate Hepatic Fibrosis in Mice

    OpenAIRE

    Paik, Yong-Han; Iwaisako, Keiko; Seki, Ekihiro; Inokuchi, Sayaka; Schnabl, Bernd; Österreicher, Christoph H.; Kisseleva, Tatiana; Brenner, David A

    2011-01-01

    NADPH oxidase (NOX) is a multicomponent enzyme that mediates electron transfer from NADPH to molecular oxygen, which leads to the production of superoxide. NOX2/gp91phox is a catalytic subunit of NOX expressed in phagocytic cells. Several homologues of NOX2, including NOX1, have been identified in non-phagocytic cells. We investigated the contributory role of NOX1 and NOX2 in hepatic fibrosis. Hepatic fibrosis was induced in wild-type (WT) mice, NOX1-knockout (NOX1KO) mice, and NOX2-knockout ...

  5. Evidence for the existence of a tyrosyl residue in the nicotinamide adenine dinucleotide binding site of chicken liver xanthine dehydrogenase

    International Nuclear Information System (INIS)

    Xanthine-NAD and NADH-methylene blue oxidoreductase activities of chicken liver xanthine dehydrogenase were inactivated by incubation with 5'-[p-(fluorosulfonyl)benzoyl]adenosine (5'-FSBA), an active site directed reagent for nucleotide binding sites. The inactivation reaction displayed pseudo-first-order kinetics. A double-reciprocal plot of inactivation velocity vs. 5'-FSBA concentration showed that 5'-FSBA and enzyme formed a complex prior to inactivation. NAD protected the enzyme from inactivation by 5'-FSBA in a competitive fashion. The modified enzyme had the same xanthine-dichlorophenolindophenol and xanthine-O2 oxidoreductase activities as the native enzyme, and on addition of xanthine to the modified enzyme, bleaching of the spectrum occurred in the visible region. The amount of radioactivity incorporated into the enzyme by incubation with [14C]-5'-FSBA was parallel to the loss of xanthine-NAD oxidoreductase activity, and the stoichiometry was 1 mol/mol of enzyme-bound FAD for complete inactivation. These results indicated that 5'-FSBA modified specifically the binding site for NAD of chicken liver xanthine dehydrogenase. The incorporated radioactivity was released slowly from 14C-labeled enzyme by incubation with dithiothreitol with concomitant restoration of catalytic activity. The modified residue responsible for inactivation was identified as a tyrosine

  6. Transient overexpression of DNA adenine methylase enables efficient and mobile genome engineering with reduced off-target effects

    DEFF Research Database (Denmark)

    Lennen, Rebecca; Nilsson Wallin, Annika; Pedersen, Margit;

    2016-01-01

    Homologous recombination of single-stranded oligonucleotides is a highly efficient process for introducing precise mutations into the genome of E. coli and other organisms when mismatch repair (MMR) is disabled. This can result in the rapid accumulation of off-target mutations that can mask desir...... reconstruct mutations found in evolved salt-tolerant strains, enabling the identification of causative mutations and isolation of strains with up to 75% increases in growth rate and greatly reduced lag times in 0.6 M NaCl....

  7. Alternative Splicing and Differential Expression of Two Transcripts of Nicotine Adenine Dinucleotide Phosphate Oxidase B Gene from Zea mays

    Institute of Scientific and Technical Information of China (English)

    Fan Lin; Yun Zhang; Ming-Yi Jiang

    2009-01-01

    With the exception of rice, little is known about the existence of respiratory burst oxidase homolog (rboh) gene in cereals. The present study reports the cloning and analysis of a novel rboh gene, termed ZmrbohB, from maize (Zea mays L.). The full-length cDNA of ZmrbohB encodes a 942 amino acid protein containing all of the respiratory burst oxidase homolog catalytically critical motifs.Altemative splicing of ZmrbohB has generated two transcript isoforms, ZmrbohB-α and -β. Spliced transcript ZmrbohB-β retains an unspliced intron 11 that carries a premature termination codon and probably leads to nonsense-mediated mRNA decay. Expression analysis showed that two splice isoforms were differentially expressed in various tissues and at different developmental stages, and the major product was ZmrbohB-α. The transcripts of ZmrbohB-α accumulated markedly when the maize seedlings were subjected to various abiotic stimuli, such as wounding, cold (4℃), heat (40℃), UV and salinity stress. In addition, several abiotic stimuli also affected the alternative splicing pattern of ZmrbohB except wounding. These results provide new insight into roles in the expression regulation of plant rboh genes and suggest that ZmrbohB gene may play a role in response to environmental stresses.

  8. Resistant starch alters gut microbiota and reduces uremic retention solutes in rats with adenine-induced chronic kidney disease

    Science.gov (United States)

    Chronic kidney disease (CKD) is characterized by the reduced ability to void urine, leading to accumulation of waste products in the body. Recently, it has been observed that patients with CKD have an altered gut microbiome. This may in part be due to reduced fiber intake. Patients with CKD are ofte...

  9. {sup 19}F-labeling of the adenine H2-site to study large RNAs by NMR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Sochor, F. [Johann Wolfgang Goethe-University Frankfurt, Institut für Organische Chemie und Chemische Biologie, Center for Biomolecular Magnetic Resonance (BMRZ) (Germany); Silvers, R. [Massachusetts Institute of Technology, Department of Chemistry, Francis Bitter Magnet Laboratory (United States); Müller, D.; Richter, C.; Fürtig, B., E-mail: fuertig@nmr.uni-frankfurt.de; Schwalbe, H., E-mail: schwalbe@nmr.uni-frankfurt.de [Johann Wolfgang Goethe-University Frankfurt, Institut für Organische Chemie und Chemische Biologie, Center for Biomolecular Magnetic Resonance (BMRZ) (Germany)

    2016-01-15

    In comparison to proteins and protein complexes, the size of RNA amenable to NMR studies is limited despite the development of new isotopic labeling strategies including deuteration and ligation of differentially labeled RNAs. Due to the restricted chemical shift dispersion in only four different nucleotides spectral resolution remains limited in larger RNAs. Labeling RNAs with the NMR-active nucleus {sup 19}F has previously been introduced for small RNAs up to 40 nucleotides (nt). In the presented work, we study the natural occurring RNA aptamer domain of the guanine-sensing riboswitch comprising 73 nucleotides from Bacillus subtilis. The work includes protocols for improved in vitro transcription of 2-fluoroadenosine-5′-triphosphat (2F-ATP) using the mutant P266L of the T7 RNA polymerase. Our NMR analysis shows that the secondary and tertiary structure of the riboswitch is fully maintained and that the specific binding of the cognate ligand hypoxanthine is not impaired by the introduction of the {sup 19}F isotope. The thermal stability of the {sup 19}F-labeled riboswitch is not altered compared to the unmodified sequence, but local base pair stabilities, as measured by hydrogen exchange experiments, are modulated. The characteristic change in the chemical shift of the imino resonances detected in a {sup 1}H,{sup 15}N-HSQC allow the identification of Watson–Crick base paired uridine signals and the {sup 19}F resonances can be used as reporters for tertiary and secondary structure transitions, confirming the potential of {sup 19}F-labeling even for sizeable RNAs in the range of 70 nucleotides.

  10. Chloroethyinitrosourea-derived ethano cytosine and adenine adducts are substrates for escherichia coli glycosylases excising analogous etheno adducts

    Energy Technology Data Exchange (ETDEWEB)

    Guliaev, Anton B.; Singer, B.; Hang, Bo

    2004-05-05

    Exocyclic ethano DNA adducts are saturated etheno ring derivatives formed mainly by therapeutic chloroethylnitrosoureas (CNUs), which are also mutagenic and carcinogenic. In this work, we report that two of the ethano adducts, 3,N{sup 4}-ethanocytosine (EC) and 1,N{sup 6}-ethanoadenine (EA), are novel substrates for the Escherichia coli mismatch-specific uracil-DNA glycosylase (Mug) and 3-methyladenine DNA glycosylase II (AlkA), respectively. It has been shown previously that Mug excises 3,N{sup 4}-ethenocytosine ({var_epsilon}C) and AlkA releases 1,N{sup 6}-ethenoadenine ({var_epsilon}A). Using synthetic oligonucleotides containing a single ethano or etheno adduct, we found that both glycosylases had a {approx}20-fold lower excision activity toward EC or EA than that toward their structurally analogous {var_epsilon}C or {var_epsilon}A adduct. Both enzymes were capable of excising the ethano base paired with any of the four natural bases, but with varying efficiencies. The Mug activity toward EC could be stimulated by E. coli endonuclease IV and, more efficiently, by exonuclease III. Molecular dynamics (MD) simulations showed similar structural features of the etheno and ethano derivatives when present in DNA duplexes. However, also as shown by MD, the stacking interaction between the EC base and Phe 30 in the Mug active site is reduced as compared to the {var_epsilon}C base, which could account for the lower EC activity observed in this study.

  11. Chemical and structural characterization of interstrand cross-links formed between abasic sites and adenine residues in duplex DNA

    Science.gov (United States)

    Price, Nathan E.; Catalano, Michael J.; Liu, Shuo; Wang, Yinsheng; Gates, Kent S.

    2015-01-01

    A new type of interstrand DNA–DNA cross-link between abasic (Ap) sites and 2′-deoxyadenosine (dA) residues was recently reported, but the chemical structure and properties of this lesion were not rigorously established. Here we characterized the nucleoside cross-link remnant released by enzymatic digestion of duplex DNA containing the dA-Ap cross-link. A synthetic standard was prepared for the putative nucleoside cross-link remnant 6 in which the anomeric carbon of the 2-deoxyribose residue was connected to the exocyclic N6-amino group of dA. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis showed that the synthetic material 6 matched the authentic cross-link remnant released by enzymatic digestion of cross-linked DNA. These findings establish the chemical structure of the dA-Ap cross-link released from duplex DNA and may provide methods for the detection of this lesion in cellular DNA. Both the nucleoside cross-link remnant 6 and the cross-link in duplex DNA were quite stable at pH 7 and 37°C, suggesting that the dA-Ap cross-link could be a persistent lesion with the potential to block the action of various DNA processing enzymes. PMID:25779045

  12. Sjögren-Larsson syndrome. Impaired fatty alcohol oxidation in cultured fibroblasts due to deficient fatty alcohol:nicotinamide adenine dinucleotide oxidoreductase activity.

    OpenAIRE

    Rizzo, W B; Dammann, A L; Craft, D A

    1988-01-01

    Lipid metabolism was studied in cultured skin fibroblasts from patients with the inherited disorder, Sjögren-Larsson syndrome (SLS). Intact SLS fibroblasts incubated in the presence of [1-14C]palmitate accumulated more radioactive hexadecanol than did normal cells, whereas incorporation of radioactivity into other cellular lipids was unaltered. The hexadecanol content of SLS fibroblasts was abnormally elevated. Hexadecanol accumulation was not due to increased fatty alcohol synthesis nor its ...

  13. The activity of uridine diphosphate-D-glucose: Nicotinamide-adenine dinucleotide oxidoreductase in cambial tissue and differentiating xylem isolated from sycamore trees.

    Science.gov (United States)

    Rubery, P H

    1972-06-01

    The activity of UDPGlc: NAD oxidoreductase is measured in enzyme preparations obtained from sycamore cambium and xylem tissue. The activity of this enzyme is greater in xylem than in cambium whether expressed on a specific activity basis or on a per-cell basis. It is suggested that, in developing xylem, direct oxidation of UDPGlc may contribute significantly to the biosynthesis of polysaccharide precursors.

  14. Enhanced Reduced Nicotinamide Adenine Dinucleotide electrocatalysis onto multi-walled carbon nanotubes-decorated gold nanoparticles and their use in hybrid biofuel cell

    Science.gov (United States)

    Aquino Neto, S.; Almeida, T. S.; Belnap, D. M.; Minteer, S. D.; De Andrade, A. R.

    2015-01-01

    We report the preparation of Au nanoparticles synthetized by different protocols and supported on the surface of multi-walled carbon nanotubes containing different functional groups, focusing on their electrochemical performance towards NADH oxidation, ethanol bioelectrocatalysis, and ethanol/O2 biofuel cell. We describe four different synthesis protocols: microwave-assisted heating, water-in-oil, and dendrimer-encapsulated nanoparticles using acid or thiol species in the extraction step. The physical characterization of the metallic nanoparticles indicated that both the synthetic protocol as well as the type of functional groups on the carbon nanotubes affect the final particle size (varying from 13.4 to 2.4 nm) and their distribution onto the carbon surface. Moreover, the electrochemical data indicated that these two factors also influence their performance toward the electrooxidation of NADH. We observed that the samples containing Au nanoparticles with smaller size leads to higher catalytic currents and also shifts the oxidation potential of the targeted reaction, which varied from 0.13 to -0.06 V vs Ag/AgCl. Ethanol/O2 biofuel cell tests indicated that the hybrid bioelectrodes containing smaller and better distributed Au nanoparticles on the surface of carbon nanotubes generates higher power output, confirming that the electrochemical regeneration of NAD+ plays an important role in the overall biofuel cell performance.

  15. Flavin Adenine Dinucleotide Status and the Effects of High-Dose Riboflavin Treatment in Short-Chain Acyl-CoA Dehydrogenase Deficiency

    NARCIS (Netherlands)

    B.T. Maldegem; M. Duran; R.J.A. Wanders; H.R. Waterham; F.A. Wijburg

    2010-01-01

    Short-chain acyl-CoA dehydrogenase deficiency (SCADD) is an inborn error, biochemically characterized by increased plasma butyrylcarnitine (C4-C) concentration and increased ethylmalonic acid (EMA) excretion and caused by rare mutations and/or common gene variants in the SCAD encoding gene. Although

  16. Enhancement of photophysical and photosensitizing properties of flavin adenine dinucleotide by mutagenesis of the C-terminal extension of a bacterial flavodoxin reductase.

    Science.gov (United States)

    Valle, Lorena; Abatedaga, Inés; Vieyra, Faustino E Morán; Bortolotti, Ana; Cortez, Néstor; Borsarelli, Claudio D

    2015-03-16

    The role of the mobile C-terminal extension present in Rhodobacter capsulatus ferredoxin-NADP(H) reductase (RcFPR) was evaluated using steady-state and dynamic spectroscopies for both intrinsic Trp and FAD in a series of mutants in the absence of NADP(H). Deletion of the six C-terminal amino acids beyond Ala266 was combined with the replacement A266Y to emulate the structure of plastidic reductases. Our results show that these modifications of the wild-type RcFPR produce subtle global conformational changes, but strongly reduce the local rigidity of the FAD-binding pocket, exposing the isoalloxazine ring to the solvent. Thus, the ultrafast charge-transfer quenching of (1) FAD* by the conserved Tyr66 residue was absent in the mutant series, producing enhancement of the excited singlet- and triplet-state properties of FAD. This work highlights the delicate balance of the specific interactions between FAD and the surrounding amino acids, and how the functionality and/or photostability of redox flavoproteins can be modified. PMID:25641205

  17. Properties of the mitochondrial carrier of adenine-nucleotide after purification. Study of the transport protein under isolated form and reincorporated form in phospho-lipidic vesicles

    International Nuclear Information System (INIS)

    The first part of this research thesis addresses the reconstitution of the ADP/ATP transport by incorporation of the specific carrier, isolated in presence of detergent, in phospholipids vesicles. Fundamental properties of the reconstituted transport are identical to that of transport in mitochondria, notably as far as the exchange stoichiometry, the turn over and the transport Km are concerned, as well as the asymmetric orientation of the carrier in the membrane. The second part of this research addresses the study of interactions of specific ligands with the ADP/ATP transport protein in presence of detergent. The study of the variations of the intrinsic fluorescence of the isolated ADP/ATP carrier highlights conformational changes exclusively induced by the presence of transportable nucleotides which are modulated in a different manner by carboxy-atractyloside or bongkrekic acid. Moreover, by using the isolated protein, a detailed analysis of binding parameters of fluorescent analogues of ATP is reported

  18. Towards understanding the origins of the different specificities of binding the reduced (NADPH) and oxidised (NADP +) forms of nicotinamide adenine dinucleotide phosphate coenzyme to dihydrofolate reductase

    Science.gov (United States)

    Polshakov, Vladimir I.; Biekofsky, Rodolfo R.; Birdsall, Berry; Feeney, James

    2002-01-01

    Lactobacillus casei dihydrofolate reductase (DHFR) binds more than a thousand times tighter to NADPH than to NADP +. The origins of the difference in binding affinity to DHFR between NADPH and NADP + are investigated in the present study using experimental NMR data and hybrid density functional, B3LYP, calculations. Certain protein residues (Ala 6, Gln 7, Ile 13 and Gly 14) that are directly involved in hydrogen bonding with the nicotinamide carboxamide group show consistent differences in 1H and 15N chemical shift between NADPH and NADP + in a variety of ternary complexes. B3LYP calculations in model systems of protein-coenzyme interactions show differences in the H-bond geometry and differences in charge distribution between the oxidised and reduced forms of the nicotinamide ring. GIAO isotropic nuclear shieldings calculated for nuclei in these systems reproduce the experimentally observed trends in magnitudes and signs of the chemical shifts. The experimentally observed reduction in binding of NADP + compared with NADPH results partly from NADP + having to change its nicotinamide amide group from a cis- to a trans-conformation on binding and partly from the oxidised nicotinamide ring of NADP + being unable to take up its optimal hydrogen bonding geometry in its interactions with protein residues.

  19. Mutations in PurBox1 of the Bacillus subtilis pur operon control site affect adenine-regulated expression in vivo

    Institute of Scientific and Technical Information of China (English)

    XUAN; Jinsong; Howard; Zalkin; WENG; Manli

    2005-01-01

    Transcription of the Bacillus subtilis pur operon is regulated by a purine repressor (PurR)-DNA control site interaction. The pur operon control site has two PurBoxes that are required for high-affinity PurR binding. An upstream, strong-binding PurBox1 is at position -81 to -68 relative to the transcription start site and a downstream weak-binding PurBox2 is at position -49 to -36. We constructed three PurBox1 mutations and the effects on binding of PurR to the control region in vitro and on regulation of pur operon expression in vivo were investigated. The mutations significantly reduced the binding of PurR to control region DNA. In strains with G-75A, G-75T and a five bp deletion (△5) pur operon repression was defective in vivo. In addition in vivo PurR titration was used to confirm that sequences flanking PurBox1 and PurBox2 are required for PurR binding to the pur operon control site.

  20. Wiring of Glucose Oxidizing Flavin Adenine Dinucleotide-Dependent Enzymes by Methylene Blue-Modified Third Generation Poly(amidoamine) Dendrimers Attached to Spectroscopic Graphite Electrodes

    DEFF Research Database (Denmark)

    Castaing, Victor; Álvarez-Martos, Isabel; Ferapontova, Elena

    2016-01-01

    ordered multiple redox centers, represent an advanced alternative to the existing approaches. Here we show that methylene blue (MB)-labeled G3 PAMAM dendrimers covalently attached to the high-surface area spectroscopic graphite (Gr) electrodes form stable and spatially resolved electronic wires......, characterized by the heterogeneous ET rate constant of 7.1 0.1 s1; they can be used for electronic wiring of glucose-oxidizing FAD-containing enzymes, such as hexose oxidase (HOX), and further bioelectrocatalysis of glucose oxidation, starting, at pH 7, from -100 mV vs. Ag/AgCl. Thus, dendrimer......-templated electronic wires, comprising MB molecules conjugated to the periphery of the PAMAM and anchored to the surface of cost-effective Gr electrodes represent an efficient and robust tool for protein wiring to electrodes for their perspective bioelectronic applications in biosensors and biofuel cells....

  1. Wiring of Glucose Oxidizing Flavin Adenine Dinucleotide-Dependent Enzymes by Methylene Blue-Modified Third Generation Poly(amidoamine) Dendrimers Attached to Spectroscopic Graphite Electrodes

    DEFF Research Database (Denmark)

    Castaing, Victor; Álvarez-Martos, Isabel; Ferapontova, Elena

    2016-01-01

    Electro-enzymatic biotransformation requires an efficient and robust electronic communication between the biomolecules and electrodes, often performed by the relevant electron transfer (ET) mediating systems. Of those, redox-labeled dendrimeric structures, biocompatible and bearing spatially orde...

  2. QM/MM Simulation of the Hydrogen Bond Dynamics of an Adenine:Uracil Base Pair in Solution. Geometric Correlations and Infrared Spectrum

    CERN Document Server

    Yan, Yun-an

    2009-01-01

    Hybrid QM(DFT)/MM molecular dynamics simulations have been carried out for the Watson-Crick base pair of 9-ethyl-8-phenyladenine and 1-cyclohexyluracil in deuterochloroform solution at room temperature. Trajectories are analyzed putting special attention to the geometric correlations of the $\\NHN$ and $\\NHO$ hydrogen bonds in the base pair. Further, based on empirical correlations between the hydrogen bond bond length and the fundamental NH stretching frequency its fluctuations are obtained along the trajectory. Using the time dependent frequencies the infrared lineshape is determined assuming the validity of a second order cumulant expansion. The deviations for the fundamental transition frequencies are calculated to amount to less than 2% as compared with experiment. The width of the spectrum for the $\\NHN$ bond is in reasonable agreement with experiment while that for the $\\NHO$ case is underestimated by the present model. Comparing the performance of different pseudopotentials it is found that the Troulli...

  3. QM/MM Lineshape Simulation of the Hydrogen-bonded Uracil NH Stretching Vibration of the Adenine:Uracil Base Pair in CDCl$_3$

    CERN Document Server

    Yan, Yun-an; Kühn, Oliver

    2008-01-01

    A hybrid Car-Parrinello QM/MM molecular dynamics simulation has been carried out for the Watson-Crick base pair of 9-ethyl-8-phenyladenine and 1-cyclohexyluracil in deuterochloroform solution at room temperature. The resulting trajectory is analyzed putting emphasis on the N-H$...$N Hydrogen bond geometry. Using an empirical correlation between the $\\NN$-distance and the fundamental NH-stretching frequency, the time-dependence of this energy gap along the trajectory is obtained. From the gap-correlation function we determine the infrared absorption spectrum using lineshape theory in combination with a multimode oscillator model. The obtained average transition frequency and the width of the spectrum is in reasonable agreement with recent experimental data.

  4. Novel concept of enzyme selective nicotinamide adenine dinucleotide (NAD)-modified inhibitors based on enzyme taxonomy from the diphosphate conformation of NAD.

    Science.gov (United States)

    Fujii, Mikio; Kitagawa, Yasuyuki; Iida, Shui; Kato, Keisuke; Ono, Machiko

    2015-11-15

    The dihedral angle θ of the diphosphate part of NAD(P) were investigated to distinguish the differences in the binding-conformation of NAD(P) to enzymes and to create an enzyme taxonomy. Furthermore, new inhibitors with fixed dihedral angles showed that enzymes could recognize the differences in the dihedral angle θ. We suggest the taxonomy and the dihedral angle θ are important values for chemists to consider when designing inhibitors and drugs that target enzymes.

  5. Drug: D04959 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D04959 Mixture, Drug Liver extract - flavin adenine dinucleotide; Liver extract - f...lavin adenine dinucleotide sodium; Adelavin (TN) Liver extract, (Flavin adenine dinucleotide [DR:D00005] | F...erapeutics 3262 Hepatic agents D04959 Liver extract - flavin adenine dinucleotide PubChem: 17398233 ...

  6. Deficiency of the reduced nicotinamide adenine dinucleotide dehydrogenase component of complex I of mitochondrial electron transport. Fatal infantile lactic acidosis and hypermetabolism with skeletal-cardiac myopathy and encephalopathy.

    OpenAIRE

    Hoppel, C L; Kerr, D S; Dahms, B; Roessmann, U

    1987-01-01

    A mitochondrial defect was investigated in an infant with fatal congenital lactic acidosis (3-14 mM), high lactate-to-pyruvate ratio, hypotonia, and cardiomyopathy. His sister had died with a similar disorder. Resting oxygen consumption was 150% of controls. Pathological findings included increased numbers of skeletal muscle mitochondria (many with proliferated, concentric cristae), cardiomegaly, fatty infiltration of the viscera, and spongy encephalopathy. Mitochondria from liver and muscle ...

  7. Molecular and crystal structures of dialkylated adenines ( N6, N9-Me 2Ade, N3, N6-MeBnAde) and cytosines ( N1, N4-Me 2Cyt)

    Science.gov (United States)

    Krüger, Thomas; Wagner, Christoph; Bruhn, Clemens; Lis, Tadeusz; Steinborn, Dirk

    2008-11-01

    N6, N9-Dimethyladenine ( N6, N9-Me 2Ade, 1) and N1, N4-dimethylcytosine ( N1, N4-Me 2Cyt, 3) were obtained by conventional methods, whereas the reaction of N6-benzyladenine with MeI/NaOH resulted in the formation of N3, N6-MeBnAde ( 2a) and N6, N9-BnMeAde ( 2b). All compounds were fully characterized by microanalysis, NMR spectroscopy ( 1H, 13C) and 1, 2a·2MeOH and 3 also by single-crystal X-ray diffraction analyses. In single-crystals of 1, obtained from THF solutions, twofold N6-H···N7' hydrogen-bonded dimeric units ( N6, N9-Me 2Ade) 2 (AA1 2 type according to Jeffrey and Saenger, 1991) were found. This proved to be another modification than that obtained by crystallization N6, N9-Me 2Ade from MeOH/PhCl (Sternglanz, 1978). Crystals of 2a·2MeOH exhibited an analogous hydrogen bond pattern as found in 1. The shorter N6···N7' distance in 2a·2MeOH (2.932(2) Å) indicates slightly stronger hydrogen bonds than in 1 (3.078(3) Å). Crystals of 3 are built up from centrosymmetric dimers ( N1, N4-Me 2Cyt) 2 having a twofold N4-H···N3' hydrogen bond, thus exhibiting the CC3 2 hydrogen bond pattern. The hydrogen bonding patterns in the dialkylated nucleobase derivatives are discussed in terms of those found in crystals of the less substituted nucleobases N9-MeAde and Cyt/ N1-MeCyt, respectively.

  8. Ultra-performance liquid chromatography tandem mass-spectrometry (uplc-ms/ms) for the rapid, simultaneous analysis of thiamin, riboflavin, flavin adenine dinucleotide, nicotinamide and pyridoxal in human milk

    Science.gov (United States)

    A novel, rapid and sensitive Ultra Performance Liquid-Chromatography tandem Mass-Spectrometry (UPLC-MS/MS) method for the simultaneous determination of several B-vitamins in human milk was developed. Resolution by retention time or multiple reaction monitoring (MRM) for thiamin, riboflavin, flavin a...

  9. Hairpin loops consisting of single adenine residues closed by sheared A.A and G.G pairs formed by the DNA triplets AAA and GAG: solution structure of the d(GTACAAAGTAC) hairpin.

    Science.gov (United States)

    Chou, S H; Zhu, L; Gao, Z; Cheng, J W; Reid, B R

    1996-12-20

    The DNA undecamers GTACAAAGTAC (AAA 11-mer) and GTACGAGGTAC (GAG 11-mer) have been studied in solution by high-resolution NMR spectroscopy. Both duplexes form stable hairpins containing single deoxyadenosine loops and stems containing five base-pairs that are closed at the loop end by sheared AxA and GxC pairs, respectively. These molecules thus contain new AAA and GAG loop turn motifs. All protons, including the chiral H5'/H5" protons of the loop residues, were assigned using NOESY, DQF-COSY and heteronuclear 1H-31P COSY experiments. The backbone torsion angles were constrained using experimental data from NOE crosspeaks, three-bond 1H-1H coupling constants and four-bond 1H-31P coupling constants and four-bond 1H-31P coupling constants. The AAA and GAG 11-mers form similar structures in solution. The detailed structure of the AAA 11-mer was determined by the combined use of NMR, distance geometry and energy minimization methods. This structure exhibits good stacking of the loop adenosine base on the closing 5Ax7A sheared pair, with the 6A base stacking on the 5A base and the 6A deoxyribose stacking with the 7A base. All sugars in the AAA 11-mer hairpin adopt the typical DNA C2'-endo conformation and a sharp backbone turn occurs between residues 6A and 7A. This loop turn is brought about mainly by a change in the backbone phosphate torsion angles from zeta(g-) alpha(g-) to zeta(g+) alphat(g+) at the turn. The gamma torsion angle of residue 7A in the closing sheared pair also changes from gauche+ to trans. In Pu1NPu2 loop turns of the GCA, AAA and GAG types, the chemical shift of the H4' proton of the loop deoxyribose depends on the nature of Pu2; this reflects the stacking of the loop sugar on the Pu2 base and the different ring current effects of A or G in this position. PMID:9000625

  10. High performance liquid chromatography analysis of 9-(2',3'-dideoxy-2'beta-fluoro-D-threo-penta furanosyl) adenine and its metabolite in human plasma using solid-phase extraction on a polyfluorinated reversed stationary phase.

    Science.gov (United States)

    Aboul-Enein, H Y; Abu-Zaid, S

    2001-06-01

    A quick and sensitive reversed-phase HPLC method has been developed for the analysis of 2'-beta -fluoro-2',3'-dideoxy adenosine (F-ddA), the acid-stable anti-AIDS drug, and its metabolite 2'-fluoro-2',3'-dideoxy inosine (F-ddI) in human plasma using polyfluorinated stationary phase column (Fluo fix, 15 cm, 4.0 mm i.d., 5 microm particle size). The mobile phase consisted of ammonium phosphate buffer solution (10 mM) adjusted with phosphoric acid 85% to pH 6.8:dimethyl formamide (97:3, v/v). F-ddA and F-ddI were monitored by UV-visible detector at 258 and 247 nm, respectively. The recoveries of F-ddA and F-ddI from plasma using a C(18) solid-phase extraction cartridge were 99.2% and 99.7%, respectively. PMID:11438969

  11. Biochemical Analysis of Recombinant AlkJ from Pseudomonas putida Reveals a Membrane-Associated, Flavin Adenine Dinucleotide-Dependent Dehydrogenase Suitable for the Biosynthetic Production of Aliphatic Aldehydes

    OpenAIRE

    Kirmair, Ludwig; Skerra, Arne

    2014-01-01

    The noncanonical alcohol dehydrogenase AlkJ is encoded on the alkane-metabolizing alk operon of the mesophilic bacterium Pseudomonas putida GPo1. To gain insight into the enzymology of AlkJ, we have produced the recombinant protein in Escherichia coli and purified it to homogeneity using His6 tag affinity and size exclusion chromatography (SEC). Despite synthesis in the cytoplasm, AlkJ was associated with the bacterial cell membrane, and solubilization with n-dodecyl-β-d-maltoside was necessa...

  12. 心肌线粒体腺苷酸配体门控钙离子释放通道%A pathway for adenine nucleotide ligand gating Ca2+ efflux of myocadial mitochondria

    Institute of Scientific and Technical Information of China (English)

    康少平; 李旭光; 董嘉良; 张艳君; 康英姿; 于公元

    2008-01-01

    目的:探讨心肌线粒体腺苷酸配体门控钙离子释放通道.方法:32只Wistar大鼠随机分成4组:ATP组、ADP组、NaCl组和咖啡因(Caffeine)组,每组8只.利用差速离心的方法提取心肌细胞线粒体.分别用ATP、ADP、NaCl和Caffeine启动线粒体Ca2+释放反应.紫外分光光度计监测线粒体的Ca2+释放.结果:ATP、ADP组线粒体Ca2+释放速度及最大释放量显著高于NaCl、Caffeine组(P<0.01),差异有统计学意义.结论:ATP、ADP能够触发心肌线粒体Ca2+释放,而NaCl、Caffeine则不可以.该实验数据提示心肌线粒体存在一种腺苷酸配体门控钙离子释放通道.

  13. Efeito da sacarose, cinetina, isopentenil adenina e zeatina no desenvolvimento de embriões de Heliconia rostrata in vitro Effect of sucrose, kinetin, isopentenyl adenine and zeatin on the development of embryos of Heliconia rostrata in vitro

    OpenAIRE

    Antonio Carlos Torres; Fernanda D. Duval; Dalva G. Ribeiro; Ana Flavia F. Barros; Fernando A.D. Aragão

    2005-01-01

    Embriões provenientes de frutos maturos de Heliconia rostrata Ruiz & Pavon foram excisados e inoculados em meio de cultura contendo os sais básicos MS, vitaminas e sacarose. A adição de sacarose foi essencial para o desenvolvimento dos embriões. Em meio desprovido de sacarose os embriões morreram em cultura. Concentrações de 1%, 2% e 3% (p/v) de sacarose favoreceram o desenvolvimento dos embriões. Concentrações de 6%, 9% e 12% (p/v) de sacarose inibiram o crescimento dos embriões. A adição de...

  14. 参附强心丸对腺嘌呤致肾阳虚大鼠温阳利水作用及机制研究%Research of Effects and Mechanism of Shenfuqiangxin Pills on the Warming Yang for Diuresis of Kidney-yang Deficiency Rats Caused by AdenineΔ

    Institute of Scientific and Technical Information of China (English)

    王梓; 张浩; 郝迪; 李旭; 袁玲; 王蕾

    2015-01-01

    OBJECTIVE:To probe into the effects and mechanism of Shenfuqiangxin pills on the warming yang for diuresis of chronic renal failure rats via the link of signs, renal function, neuroendocrine hormone, serum electrolytes and renal tissue morphology, etc.METHODS:The CRF model of rat was established by“unilateral nephrectomy combined with gavageing adenine”, the rats were divided into the model control, dexamethasone group and the dosage group with Shenfuqiangxin pills of 2.14 g/kg, 1.07 g/kg, 0.54 g/kg in crude drug via the random number table.The indexes of neuroendocrine hormone, renal function, blood electrolytes, body temperature, ratio of the kidney weight versus kidney volume and the form of organization of kidney in rates were observed.RESULTS: Some asthenia signs like sparse fur, sedentary lying and emaciation were observed in rats in mode group.The general conditions in three dosage groups of Shenfuqiangxin pills had been significantly improved.Level of UREA and CREA contents increased significantly in mode group,which in three dosage groups of Shenfuqiangxin pills were significantly lower than that in mode group.In mode group and three dosage groups of Shenfuqiangxin pills, angiotensinⅡ( AngⅡ) were significantly lower than that of sham-operation group, but aldosterone (ALD) were significantly higher than that of sham-operation group.Compared with the mode group, ALD in dosage group with 2.14 g/kg Shenfuqiangxin pills and dexamethasone group were obviously decreased, the differences were statistically significant ( P <0.05 ).Hyperkalemia, low calcium and hyperphosphatemia of rats were observed in the mode group, dosage group with 2.14 g/kg Shenfuqiangxin pills could correct hypocalcemia, and three dosage groups of Shenfuqiangxin pills all could correct hyperphosphatemia; the dexamethasone group could correct hyperkalemia, low calcium and hyperphosphatemia of rats,the differences were statistically significant(P<0.05).The body temperature of rats in mode group were significantly decreased,but hypothermia were observed in dexamethasone group.The kidney weight in mode group were significantly higher than that in sham-operation group;compared with the mode group, kidney weight in dosage group with 2.14 g/kg Shenfuqiangxin pills decreased, and the kidney volume was smaller, the difference was statistically significant ( P<0.05).From the visual inspection and renal pathology, it indicated that the kidney size and lesions both had various degrees of relief in three dosage groups of Shenfuqiangxin pills and dexamethasone group.CONCLUSIONS:Shenfuqiangxin pills can improve the function of kidney-yang deficiency rats, protect the renal function, improve water and sodium retention, correct the electrolyte imbalance, and repair the renal lesions.%目的:通过体征、肾功能、神经内分泌激素、血清电解质、肾脏组织形态等环节,探讨参附强心丸对慢性肾衰竭大鼠温阳利水的作用与机制。方法:采用“单肾切除合并腺嘌呤灌胃法”制备大鼠CRF模型,按随机数字表法分为模型对照组、地塞米松对照组、参附强心丸2.14、1.07、0.54 g生药/kg剂量组,观察各组大鼠神经内分泌激素、肾功能、血电解质、体温、肾脏质量与肾体比、肾脏的组织形态等指标。结果:模型对照组大鼠出现皮毛稀疏,蜷卧少动,消瘦等衰弱体征,参附强心丸3个剂量组大鼠一般状况较模型对照组明显好转;模型对照组大鼠尿素氮( UREA)、肌酐( CREA)含量明显升高,参附强心丸3个剂量组和地塞米松对照组UREA、CREA水平均明显低于模型对照组;模型对照组和参附强心组大鼠的血管紧张素Ⅱ( AngII)显著低于假手术对照组,醛固酮( ALD)明显高于假手术对照组,参附强心丸2.14 g/kg和地塞米松对照组大鼠的ALD较模型对照组明显降低,差异均有统计学意义( P<0.05)。模型对照组大鼠呈高钾、低钙、高磷血症,参附强心丸2.14 g/kg组大鼠可纠正低血钙

  15. 日粮核苷酸对化学性肝损伤过程中肝组织腺苷酸池的影响%Effects of Dietary Nucleotides on Adenine Nucleotide Pool in Liver Tissue with Chemical Liver Injury

    Institute of Scientific and Technical Information of China (English)

    朱善良; 孙文; 许晓风

    2009-01-01

    研究了日粮核苷酸对CCl_4诱发大鼠肝损伤过程中肝组织核苷酸池的影响.结果表明,CCl_4处理组大鼠体重显著低于对照组,CCl_4-NTs组大鼠体重与对照组无显著差异.在整个试验期内,CCl_4和CCl_4-NTs组大鼠的死亡率分别为20%和7%;3组处理大鼠肝脏的ATP含量多有波动.

  16. Effects of Exogenous Hormone 6 Benzyl Adenine (6-BA) on Photosystem Ⅱ Performance of Maize during Process of Leaf Senescence under Different Nitrogen Fertilization Levels%6-苄氨基嘌呤(6-BA)对不同氮素水平下玉米叶片衰老过程中光系统Ⅱ性能的调控效应

    Institute of Scientific and Technical Information of China (English)

    陈晓璐; 李耕; 刘鹏; 高辉远; 董树亭; 王振林; 张吉旺; 赵斌

    2013-01-01

    以玉米自交系齐319 (Qi 319)为试材,利用叶绿素荧光快速诱导动力学曲线,研究了喷施外源激素6-苄氨基嘌呤(6-BA)对不同氮素水平下玉米花后叶片光系统 1 (PSⅡ)性能的调控效应.两年研究结果表明,花后穗位叶叶绿素含量和净光合速率(Pn)均呈降低趋势.在不施氮条件下,外源喷施6-BA,可提高叶绿素含量及后期Pn,但对PSⅡ反应中心的活性无显著改善.施氮可显著提高Pn和PS Ⅱ的性能,6-BA可显著增强其效果.二者互作条件下,叶绿素含量显著提高,Pn显著增加(P<0.05),PSⅡ供体侧和受体侧的活性得到有效改善,其中对PSⅡ供体侧性能的改善幅度大于对受体侧,花后10 d PSⅡ反应中心的活性提高最显著.光合性能的提高使单株生物量和籽粒产量显著增加(P<0.05).因此,在适量施用氮肥的条件下结合喷施6-BA可以显著改善叶片光合性能.

  17. NADH supplementation decreases pinacidil-primed IK(ATP) in ventricular cardiomyocytes by increasing intracellular ATP

    OpenAIRE

    Pelzmann, Brigitte; Hallström, Seth; Schaffer, Peter; Lang, Petra; Nadlinger, Karl; Birkmayer, George D; Vrecko, Karoline; Reibnegger, Gilbert; Koidl, Bernd

    2003-01-01

    The aim of this study was to investigate the effect of nicotinamide-adenine dinucleotide (NADH) supplementation on the metabolic condition of isolated guinea-pig ventricular cardiomyocytes. The pinacidil-primed ATP-dependent potassium current IK(ATP) was used as an indicator of subsarcolemmal ATP concentration and intracellular adenine nucleotide contents were measured.Membrane currents were studied using the patch-clamp technique in the whole-cell recording mode at 36–37°C. Adenine nucleotid...

  18. Lack of Maternal Glutamate Cysteine Ligase Modifier Subunit (Gclm) Decreases Oocyte Glutathione Concentrations and Disrupts Preimplantation Development in Mice

    OpenAIRE

    Nakamura, Brooke N.; Fielder, Thomas J.; Hoang, Yvonne D.; Lim, Jinhwan; McConnachie, Lisa A.; Kavanagh, Terrance J.; Luderer, Ulrike

    2011-01-01

    Glutathione (GSH) is the most abundant intracellular thiol and an important regulator of cellular redox status. Mice that lack the modifier subunit of glutamate cysteine ligase (Gclm), the rate-limiting enzyme in GSH synthesis, have decreased GSH synthesis. Nicotinamide nucleotide transhydrogenase, an inner mitochondrial membrane protein, catalyzes the interconversion of reduced nicotinamide adenine dinucleotide and reduced nicotinamide adenine dinucleotide phosphate; reduced nicotinamide ade...

  19. Drug: D07633 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D07633 Mixture, Drug Chondroitin sulfate sodium - flavin adenine dinucleotide sodium mixt; Chondroit...in sulfate sodium - FAD sodium mixt; Mucofadin (TN); Mucotear (TN) Chondroitin sulfate sodi...rgans 13 Agents affecting sensory organs 131 Ophthalmic agents 1319 Others D07633 Chondroitin sulfate sodium - flavin adenine dinucleotide sodium mixt PubChem: 96024455 ...

  20. Methylated DNA in Borrelia species.

    OpenAIRE

    Hughes, C A; Johnson, R C

    1990-01-01

    The DNA of Borrelia species was examined for the presence of methylated GATC sequences. The relapsing-fever Borrelia sp., B. coriaceae, and only 3 of 22 strains of B. burgdorferi contained adenine methylation systems. B. anserina lacked an adenine methylation system. Fundamental differences in DNA methylation exist among members of the genus Borrelia.

  1. Efficient N-Arylation and N-Alkenylation of the Five DNA/RNANucleobases

    DEFF Research Database (Denmark)

    Jacobsen, Mikkel Fog; Knudsen, Martin M.; Gothelf, Kurt Vesterager

    2006-01-01

    -substituted pyrimidin-2(1H)-one served as both a cytosine and a uracil precursor and was N-arylated and N-alkenylated in high yields. Adenine was efficiently and selectively N-arylated and N-alkenylated at the N9 position by employing a bis-Boc-protected adenine derivative, while a bis-Boc-protected 2-amino-6...

  2. A quick look at biochemistry : Carbohydrate metabolism

    NARCIS (Netherlands)

    Dashty, Monireh

    2013-01-01

    In mammals, there are different metabolic pathways in cells that break down fuel molecules to transfer their energy into high energy compounds such as adenosine-5'-triphosphate (ATP), guanosine-5'-triphosphate (GTP), reduced nicotinamide adenine dinucleotide (NADH2), reduced flavin adenine dinucleot

  3. AcEST: DK947175 [AcEST

    Lifescience Database Archive (English)

    Full Text Available GTIEATVKLIRRLGG 147 >sp|Q1RF67|APT_ECOUT Adenine phosphoribosyltransferase OS=Escherichia coli (strain UTI89 / UPEC...LGG 147 >sp|Q0TKH2|APT_ECOL5 Adenine phosphoribosyltransferase OS=Escherichia coli O6:K15:H31 (strain 536 / UPEC

  4. H-bonding-directed self-assembly of synthetic copolymers containing nucleobases: organization and colloidal fusion in a noncompetitive solvent.

    Science.gov (United States)

    Lutz, Jean-François; Pfeifer, Sebastian; Chanana, Munish; Thünemann, Andreas F; Bienert, Ralf

    2006-08-15

    The self-organization of random copolymers composed of a nucleobase monomer (either 1-(4-vinylbenzyl)thymine or 9-(4-vinylbenzyl)adenine) and dodecyl methacrylate (DMA) was studied in dilute chloroform solutions. The balance between the molar fractions of the nucleobase monomer (leading to intermolecular H-bonding) and DMA (soluble moiety in chloroform) in the polymer chains was found to be the parameter that principally influences the self-organization. DMA-rich copolymers are molecularly soluble in chloroform, whereas nucleobase-rich copolymers are insoluble in this solvent. Copolymers possessing an equimolar comonomer composition self-assemble into micrometer-sized particles physically cross-linked by intermolecular H-bonds (either thymine-thymine or adenine-adenine interactions, depending on the studied copolymer). Nevertheless, when mixed together, thymine- and adenine-based colloids fuse into thermodynamically stable microspheres cross linked by adenine-thymine interactions.

  5. Drug: D08741 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D08741 Mixture, Drug Adenine - sodium citrate hydrate - citric acid hydrate - gluco...se - potassium phosphate, monobasic mixt; CPDA solution; Karmi CA (TN) Adenine [DR:D00034], Sodium citrate hydr...ate [DR:D01781], Citric acid hydrate [DR:D01222], Glucose [DR:D00009], Sodium phosphate, monobasic Therap...eutic category: 3339 Therapeutic category of drugs in Japan [BR:br08301] 3 Agents... affecting metabolism 33 Blood and body fluid agents 333 Anticoagulants 3339 Others D08741 Adenine - sodium citrate hydr

  6. A novel mechanism for inhibition of translation by pokeweed antiviral protein: depurination of the capped RNA template.

    OpenAIRE

    Hudak, K A; Wang, P.; Tumer, N E

    2000-01-01

    Pokeweed antiviral protein (PAP) is known to inactivate ribosomes by removal of a specific adenine from the sarcin/ricin (S/R) loop of the large rRNA, thereby inhibiting translation. We demonstrate here that in addition to the previously identified adenine (A4324), PAP removes another adenine (A4321) and a guanine (G4323) from the eukaryotic large rRNA. Recent results indicate that the antiviral activity of PAP may not be due to depurination of host ribosomes. Using PAP mutants that do not de...

  7. The role of sirtuins in cellular homeostasis.

    Science.gov (United States)

    Kupis, Wioleta; Pałyga, Jan; Tomal, Ewa; Niewiadomska, Ewa

    2016-09-01

    Sirtuins are evolutionarily conserved nicotinamide adenine dinucleotide (NAD(+))-dependent lysine deacylases or ADP-ribosyltransferases. These cellular enzymes are metabolic sensors sensitive to NAD(+) levels that maintain physiological homeostasis in the animal and plant cells. PMID:27154583

  8. Decreased visfatin after exercise training correlates with improved glucose tolerance

    DEFF Research Database (Denmark)

    Haus, Jacob M; Solomon, Thomas; Marchetti, Christine M;

    2009-01-01

    Nampt/pre-B-cell colony-enhancing factor/visfatin (visfatin) release from adipocytes has recently been suggested to be nutrient responsive and linked to systemic nicotinamide adenine dinucleotide biosynthesis and regulation of pancreatic beta-cell function....

  9. Anticancer agent CHS-828 inhibits cellular synthesis of NAD

    DEFF Research Database (Denmark)

    Olesen, U.H.; Christensen, M.K.; Bjorkling, F.;

    2008-01-01

    Malignant cells display increased demands for energy production and DNA repair. Nicotinamide adenine dinucleotide (NAD) is required for both processes and is also continuously degraded by cellular enzymes. Nicotinamide phosphoribosyltransferase (Nampt) is a crucial factor in the resynthesis of NA...

  10. Detoxification and color removal of Congo red by a novel Dietzia sp. (DTS26) – A microcosm approach

    Digital Repository Service at National Institute of Oceanography (India)

    SatheeshBabu, S.; Mohandass, C.; VijayRaj, A.S.; Dhale, M.A.

    of desired concentration were obtained by successive dilution. Chemicals related to enzymatic analysis i.e., Tartaric acid, n-Propanol and Catechol were purchased from Merck-Germany. Nicotinamide adenine dinucleotide (NADH), mono sodium phosphate, di...

  11. Primaquine

    Science.gov (United States)

    ... carry oxygen to the tissues in the body),nicotinamide adenine dinucleotide (NADH) deficiency (a genetic condition), glucose- ... these symptoms, call your doctor immediately: tiredness pale skin shortness of breath fast heartbeat yellowing of the ...

  12. CdSe quantum dot internalization by Bacillus subtilis and Escherichia coli

    Science.gov (United States)

    Kloepfer, Jeremiah A.; Mielke, Randall E.; Nadeau, Jay L.

    2004-06-01

    Biological labeling has been demonstrated with CdSe quantum dots in a variety of animal cells, but bacteria are harder to label because of their cell walls. We discuss the challenges of using minimally coated, bare CdSe quantum dots as luminescent internal labels for bacteria. These quantum dots were solubilized with mercaptoacetic acid and conjugated to adenine. Significant evidence for the internal staining of Bacillus subtilis (Gram positive) and Escherichia coli (Gram negative) using these structures is presented via steady-state emission, epifluorescence microscopy, transmission electron microscopy, and energy dispersive spectroscopy. In particular, the E. coli adenine auxotroph, and not the wild type, took up adenine coated quantum dots, and this only occurred in adenine deficient growth media. Labeling strength was enhanced by performing the incubation under room light. This process was examined with steady-state emission spectra and time-resolved luminescence profiles obtained from time-correlated-single-photon counting.

  13. HepG2 cells develop signs of riboflavin deficiency within four days of culture in riboflavin-deficient medium*

    OpenAIRE

    Werner, Ricarda; MANTHEY, KAROLINE C.; Griffin, Jacob B.; Zempleni, Janos

    2005-01-01

    Flavin mononucleotide and flavin adenine dinucleotide are essential coenzymes in redox reactions. For example, flavin adenine dinucleotide is a coenzyme for both glutathione reductase and enzymes that mediate the oxidative folding of secretory proteins. Here we investigated short-term effects of moderately riboflavin-deficient culture medium on flavin-related responses in HepG2 hepatocarcinoma cells. Cells were cultured in riboflavin-deficient (3.1 nmol/L) medium for up to six days; controls ...

  14. 黄精核糖体灭活蛋白双元表达载体的构建与鉴定%Construction of Binary Vector pGV4945 of Ribosome-Inactivating Protein Gene from Polygonatum multiflorum

    Institute of Scientific and Technical Information of China (English)

    常维山; Henry De Greve; 翟静; Nele Buys; Jan Pierre Hernal Steens

    2004-01-01

    Ribosome-inactivating proteins (RIPs)have been known to have cytotoxic activity by cleaving a specific adenine residue of 28S rRNA. RIPs can be divided into, type 1 and type 2. Type 2 is a toxic protein that was consisted of two Gal/GalNAc-binding chains, A and B Chains that connected through a disulfide linkage. The A chain of RIP has RNA N-glycosidase activity to cleave a specific adenine base from ribosomal RNA,

  15. Urinary L-Type Fatty Acid-Binding Protein Can Reflect Renal Tubulointerstitial Injury

    OpenAIRE

    Tanaka, Tamami; DOI, Kent; Maeda-Mamiya, Rui; Negishi, Kousuke; Portilla, Didier; Sugaya, Takeshi; Fujita, Toshiro; Noiri, Eisei

    2009-01-01

    This study aimed to elucidate the role of L-type fatty acid-binding protein (L-FABP) in renal tubulointerstitial injury using a mouse adenine-induced renal injury model. C57BL/6 mice fed excess dietary adenine for 6 weeks showed a gradual increase in levels of blood urea nitrogen (BUN). They also showed severe tubulointerstitial pathological findings, such as fibrosis and macrophage infiltration without glomerular damage, which were attenuated by treatment with either allopurinol or Y-700, a ...

  16. APRT部分欠損症による2,8-dihydroxyadenine結石症の2例

    OpenAIRE

    大沢, 理; 大原, 孝; 小松, 洋輔

    1991-01-01

    We report two cases of 2.8-dihydroxyadenine stones due to partial deficiency of adenine phosphoribosyltransferase. The first patient is a 41-year-old female. Radiologic examination revealed left radiolucent renal stones and contracted kidney. Left nephrectomy was performed. Infrared spectrometric analysis of the stones revealed 2.8-dihydroxyadenine calculi. The adenine phosphoribosyltransferase activity in lymphocyte (T cell) was 19.5% of the control level. After the operation, the patient wa...

  17. Stabilization of a histidine-producing strain of Serratia marcescens.

    OpenAIRE

    Sugiura, M; Kisumi, M

    1984-01-01

    A decrease in histidine productivity was observed during subculture of a histidine-producing strain of Serratia marcescens. The decrease was accompanied by an increase in the number of wild-type revertants. Adenine accelerated the growth of producing strain HT-2892 to nearly equal that of revertants, and histidine production was stable because the depletion of ATP in strain HT-2892 was restored by adenine. To increase the intracellular ATP content, mutants resistant to 6-methylpurine, an anta...

  18. Detecting Ricin: A Sensitive Luminescent Assay for Ricin A-chain Ribosome Depurination Kinetics+

    OpenAIRE

    Sturm, Matthew B.; Schramm, Vern L.

    2009-01-01

    Ricin is a family member of the lethal ribosome-inactivating proteins (RIP) found in plants. Ricin toxin A-chain (RTA) from castor beans catalyzes the hydrolytic depurination of a single base from a GAGA tetraloop of eukaryotic ribosomal RNA to release a single adenine from the sarcin-ricin loop (SRL). Protein synthesis is inhibited by loss of elongation factor binding resulting in cell death. We report a sensitive coupled assay for the measurement of adenine released from ribosomes or small ...

  19. Single-step Charge Transport through DNA over Long Distances

    OpenAIRE

    Genereux, Joseph C.; Wuerth, Stephanie M.; Barton, Jacqueline K.

    2011-01-01

    Quantum yields for charge transport across adenine tracts of increasing length have been measured by monitoring hole transport in synthetic oligonucleotides between photoexcited 2-aminopurine, a fluorescent analogue of adenine, and N2-cyclopropyl guanine. Using fluorescence quenching, a measure of hole injection, and hole trapping by the cyclopropyl guanine derivative, we separate the individual contributions of single- and multi-step channels to DNA charge transport, and find that with 7 or ...

  20. Tight-binding parameters for charge transfer along DNA

    OpenAIRE

    Hawke, L. G.D.; Kalosakas, G.; Simserides, C.

    2009-01-01

    We systematically examine all the tight-binding parameters pertinent to charge transfer along DNA. The $\\pi$ molecular structure of the four DNA bases (adenine, thymine, cytosine, and guanine) is investigated by using the linear combination of atomic orbitals method with a recently introduced parametrization. The HOMO and LUMO wavefunctions and energies of DNA bases are discussed and then used for calculating the corresponding wavefunctions of the two B-DNA base-pairs (adenine-thymine and gua...

  1. Direct Base-to-Base Transitions in ssDNA Revealed by Tip-Enhanced Raman Scattering

    CERN Document Server

    Lin, Xiu-Mei; Singh, Prabha; Siegmann, Michael; Kupfer, Stephan; Zhang, Zhenglong; Gräfe, Stefanie; Deckert, Volker

    2016-01-01

    In the present contribution, specifically designed single-stranded DNA (ssDNA) sequences composed of adenine and cytosine were used as nanometric rulers to target the maximum achievable spatial resolution of tip-enhanced Raman spectroscopy (TERS) under ambient conditions. By stepping along a strand with a TERS tip, the obtained spectra allowed for a clear spectral discrimination including conformational information of the nucleobases, and even sharp adenine-cytosine transitions were detected repeatedly with a spatial resolution below 1 nm.

  2. A Prebiotic Chemistry Experiment on the Adsorption of Nucleic Acids Bases onto a Natural Zeolite

    Science.gov (United States)

    Anizelli, Pedro R.; Baú, João Paulo T.; Gomes, Frederico P.; da Costa, Antonio Carlos S.; Carneiro, Cristine E. A.; Zaia, Cássia Thaïs B. V.; Zaia, Dimas A. M.

    2015-09-01

    There are currently few mechanisms that can explain how nucleic acid bases were synthesized, concentrated from dilute solutions, and/or protected against degradation by UV radiation or hydrolysis on the prebiotic Earth. A natural zeolite exhibited the potential to adsorb adenine, cytosine, thymine, and uracil over a range of pH, with greater adsorption of adenine and cytosine at acidic pH. Adsorption of all nucleic acid bases was decreased in artificial seawater compared to water, likely due to cation complexation. Furthermore, adsorption of adenine appeared to protect natural zeolite from thermal degradation. The C=O groups from thymine, cytosine and uracil appeared to assist the dissolution of the mineral while the NH2 group from adenine had no effect. As shown by FT-IR spectroscopy, adenine interacted with a natural zeolite through the NH2 group, and cytosine through the C=O group. A pseudo-second-order model best described the kinetics of adenine adsorption, which occurred faster in artificial seawaters.

  3. Mammalian adaptation to extrauterine environment: mitochondrial functional impairment caused by prematurity.

    Science.gov (United States)

    Valcarce, C; Izquierdo, J M; Chamorro, M; Cuezva, J M

    1994-01-01

    In this paper we report that, compared with term rat neonates, both mitochondrial content and function are diminished in liver of preterm neonates (delivered 24 h before full term) compromising cellular energy provision in the postnatal period. In addition, there is a parallel reduction in the content of mRNAs encoding mitochondrial proteins in preterm rats. Also, efficient oxidative phosphorylation is not attained in these pups until 3 h after birth. Although isolated liver mitochondria from preterm neonates show a two-fold increase in F1-ATPase beta-subunit and cytochrome c oxidase activity 1 h after birth, the abnormal coupling efficiency between respiration and oxidative phosphorylation (ADP/O ratio) is due to maintenance of high H(+)-leakage values in the inner mitochondrial membrane. Postnatal reduction of the H+ leak occurs concomitantly with an increase in intra-mitochondrial adenine nucleotide concentration. Accumulation of adenine nucleotides in preterm and term liver mitochondria parallels the postnatal increase in total liver adenine nucleotides. Delayed postnatal induction of adenine biosynthesis most likely accounts for the lower adenine nucleotide pool in the liver of preterm neonates. The delayed postnatal accumulation of adenine nucleotides in mitochondria is thus responsible for the impairment in oxidative phosphorylation displayed by organelles of the preterm liver. Images Figure 1 PMID:7980455

  4. Detecting ricin: sensitive luminescent assay for ricin A-chain ribosome depurination kinetics.

    Science.gov (United States)

    Sturm, Matthew B; Schramm, Vern L

    2009-04-15

    Ricin is a family member of the lethal ribosome-inactivating proteins (RIP) found in plants. Ricin toxin A-chain (RTA) from castor beans catalyzes the hydrolytic depurination of a single base from a GAGA tetraloop of eukaryotic rRNA to release a single adenine from the sarcin-ricin loop (SRL). Protein synthesis is inhibited by loss of the elongation factor binding site resulting in cell death. We report a sensitive coupled assay for the measurement of adenine released from ribosomes or small stem-loop RNAs by RTA catalysis. Adenine phosphoribosyl transferase (APRTase) and pyruvate orthophosphate dikinase (PPDK) convert adenine to ATP for quantitation by firefly luciferase. The resulting AMP is cycled to ATP to give sustained luminescence proportional to adenine concentration. Subpicomole adenine quantitation permits the action of RTA on eukaryotic ribosomes to be followed in continuous, high-throughput assays. Facile analysis of RIP catalytic activity will have applications in plant toxin detection, inhibitor screens, mechanistic analysis of depurinating agents on oligonucleotides and intact ribosomes, and in cancer immunochemotherapy. Kinetic analysis of the catalytic action of RTA on rabbit reticulocyte 80S ribosomes establishes a catalytic efficiency of 2.6 x 10(8) M(-1) s(-1), a diffusion limited reaction indicating catalytic perfection even with large reactants. PMID:19364139

  5. Purine metabolism in Toxoplasma gondii

    Energy Technology Data Exchange (ETDEWEB)

    Krug, E.C.; Marr, J.J.; Berens, R.L.

    1989-06-25

    We have studied the incorporation and interconversion of purines into nucleotides by freshly isolated Toxoplasma gondii. They did not synthesize nucleotides from formate, glycine, or serine. The purine bases hypoxanthine, xanthine, guanine, and adenine were incorporated at 9.2, 6.2, 5.1, and 4.3 pmol/10(7) cells/h, respectively. The purine nucleosides adenosine, inosine, guanosine, and xanthosine were incorporated at 110, 9.0, 2.7, and 0.3 pmol/10(7) cells/h, respectively. Guanine, xanthine, and their respective nucleosides labeled only guanine nucleotides. Inosine, hypoxanthine, and adenine labeled both adenine and guanine nucleotide pools at nearly equal ratios. Adenosine kinase was greater than 10-fold more active than the next most active enzyme in vitro. This is consistent with the metabolic data in vivo. No other nucleoside kinase or phosphotransferase activities were found. Phosphorylase activities were detected for guanosine and inosine; no other cleavage activities were detected. Deaminases were found for adenine and guanine. Phosphoribosyltransferase activities were detected for all four purine nucleobases. Interconversion occurs only in the direction of adenine to guanine nucleotides.

  6. Optoelectronic studies on heterocyclic bases of deoxyribonucleic acid for DNA photonics.

    Science.gov (United States)

    El-Diasty, Fouad; Abdel-Wahab, Fathy

    2015-10-01

    The optoelectronics study of large molecules, particularly π-stacking molecules, such as DNA is really an extremely difficult task. We perform first electronic structure calculations on the heterocyclic bases of 2'-deoxyribonucleic acid based on Lorentz-Fresnel dispersion theory. In the UV-VIS range of spectrum, many of the optoelectronic parameters for DNA four bases namely adenine, guanine, cytosine and thymine are calculated and discussed. The results demonstrate that adenine has the highest hyperpolarizability, whereas thymine has the lowest hyperpolarizability. Cytosine has the lower average oscillator energy and the higher lattice energy. Thymine infers the most stable nucleic base with the lower phonon energy. Thymine also has the highest average oscillator energy and the lower lattice energy. Moreover, the four nucleic acid bases have large band gap energies less than 5 eV with a semiconducting behavior. Guanine shows the smallest band gap and the highest Fermi level energy, whereas adenine elucidates the highest band gap energy.

  7. Cytokinins and urea derivatives stimulate seed germination in Lotus corniculatus L.

    Directory of Open Access Journals (Sweden)

    Nikolić Radomirka

    2007-01-01

    Full Text Available We studied the effects of various cytokinins and urea derivatives on germination of aged seeds of in Lotus corniculatus L. The following substances were applied: N6-isoprenoid cytokinins (isopentenyl adenine and zeatin, adenine sulfate, N6-aromatic cytokinins (kinetin, benzyladenine and their N9-ribosides, N-benzyl-9-(2- tetrahydropyranyladenine, and urea derivatives (diphenylurea, thidiazuron, and chloro-pyridyl phenylurea. With the exception of adenine sulfate, all cytokinins increased the percentage of seed germination up to twofold, depending on their kind and concentration. It is concluded that cytokinins may be among the missing factors in aged seeds of L. corniculatus contributing to the implementation of their full germination potential. They could be used to improve germination of both freshly harvested and aged seed samples, if necessary. .

  8. Spatial, Hysteretic, and Adaptive Host-Guest Chemistry in a Metal-Organic Framework with Open Watson-Crick Sites.

    Science.gov (United States)

    Cai, Hong; Li, Mian; Lin, Xiao-Rong; Chen, Wei; Chen, Guang-Hui; Huang, Xiao-Chun; Li, Dan

    2015-09-01

    Biological and artificial molecules and assemblies capable of supramolecular recognition, especially those with nucleobase pairing, usually rely on autonomous or collective binding to function. Advanced site-specific recognition takes advantage of cooperative spatial effects, as in local folding in protein-DNA binding. Herein, we report a new nucleobase-tagged metal-organic framework (MOF), namely ZnBTCA (BTC=benzene-1,3,5-tricarboxyl, A=adenine), in which the exposed Watson-Crick faces of adenine residues are immobilized periodically on the interior crystalline surface. Systematic control experiments demonstrated the cooperation of the open Watson-Crick sites and spatial effects within the nanopores, and thermodynamic and kinetic studies revealed a hysteretic host-guest interaction attributed to mild chemisorption. We further exploited this behavior for adenine-thymine binding within the constrained pores, and a globally adaptive response of the MOF host was observed.

  9. The prebiotic synthesis of modified purines and their potential role in the RNA world

    Science.gov (United States)

    Levy, M.; Miller, S. L.; Bada, J. L. (Principal Investigator)

    1999-01-01

    Modified purines are found in all organisms in the tRNA, rRNA, and even DNA, raising the possibility of an early role for these compounds in the evolution of life. These include N6-methyladenine, 1-methyladenine, N6,N6-dimethyladenine, 1-methylhypoxanthine, 1-methylguanine, and N2-methylguanine. We find that these bases as well as a number of nonbiological modified purines can be synthesized from adenine and guanine by the simple reaction of an amine or an amino group with adenine and guanine under the concentrated conditions of the drying-lagoon or drying-beach model of prebiotic synthesis with yields as high as 50%. These compounds are therefore as prebiotic as adenine and guanine and could have played an important role in the RNA world by providing additional functional groups in ribozymes, especially for the construction of hydrophobic binding pockets.

  10. 8-cyclopropyl-2'-deoxyguanosine: a hole trap for DNA-mediated charge transport.

    Science.gov (United States)

    Wong, Jiun Ru; Shao, Fangwei

    2014-05-26

    DNA duplexes containing 8-cyclopropyl-2'-deoxyguanosine ((8CP) G) were synthesized to investigate the effect of the C8-modified deoxyguanosine as a kinetic trap for transient hole occupancy on guanines during DNA-mediated hole transport (HT). Thermal denaturation and CD spectra show that DNA duplexes containing (8CP) G are able to form stable B-form duplexes. Photoirradiation of terminal tethered anthraquinone can induce oxidative decomposition of (8CP) G through DNA HT along adenine tracts with lengths of up to 4.8 nm. Shallow and periodic distance dependence was observed in a long adenine tract with intervening guanines. The efficient charge transport indicates that (8CP) G can electronically couple well with a DNA bridge and form HT-active conformational domains to facilitate transient hole delocalization over an adenine tract. PMID:24764318

  11. Characterization of the Adsorption of Nucleic Acid Bases onto Ferrihydrite via Fourier Transform Infrared and Surface-Enhanced Raman Spectroscopy and X-ray Diffractometry.

    Science.gov (United States)

    Canhisares-Filho, José E; Carneiro, Cristine E A; de Santana, Henrique; Urbano, Alexandre; da Costa, Antonio C S; Zaia, Cássia T B V; Zaia, Dimas A M

    2015-09-01

    Minerals could have played an important role in concentration, protection, and polymerization of biomolecules. Although iron is the fourth most abundant element in Earth's crust, there are few works in the literature that describe the use of iron oxide-hydroxide in prebiotic chemistry experiments. In the present work, the interaction of adenine, thymine, and uracil with ferrihydrite was studied under conditions that resemble those of prebiotic Earth. At acidic pH, anions in artificial seawater decreased the pH at the point of zero charge (pHpzc) of ferrihydrite; and at basic pH, cations increased the pHpzc. The adsorption of nucleic acid bases onto ferrihydrite followed the order adenine > uracil > thymine. Adenine adsorption peaked at neutral pH; however, for thymine and uracil, adsorption increased with increasing pH. Electrostatic interactions did not appear to play an important role on the adsorption of nucleic acid bases onto ferrihydrite. Adenine adsorption onto ferrihydrite was higher in distilled water compared to artificial seawater. After ferrihydrite was mixed with artificial seawaters or nucleic acid bases, X-ray diffractograms and Fourier transform infrared spectra did not show any change. Surface-enhanced Raman spectroscopy showed that the interaction of adenine with ferrihydrite was not pH-dependent. In contrast, the interactions of thymine and uracil with ferrihydrite were pH-dependent such that, at basic pH, thymine and uracil lay flat on the surface of ferrihydrite, and at acidic pH, thymine and uracil were perpendicular to the surface. Ferrihydrite adsorbed much more adenine than thymine; thus adenine would have been better protected against degradation by hydrolysis or UV radiation on prebiotic Earth. PMID:26393397

  12. Hypothesis: intracellular acidification contributes to infertility in varicocele.

    Science.gov (United States)

    Ghabili, Kamyar; Shoja, Mohammadali M; Agutter, Paul S; Agarwal, Ashok

    2009-07-01

    We suggest that varicocele leads to male factor infertility by a mechanism involving underperfusion of the testis, a shortfall in glucose supply to the tissue, decreased flux through the pentose phosphate pathway, lowering of the reduced nicotinamide-adenine dinucleotide phosphate/oxidized nicotinamide-adenine dinucleotide phosphate ratio and the supply of glutathione to the antioxidant systems, increased levels of reactive oxygen species, peroxidation of spermatozoon membrane lipids, and the consequent generation of acidic degradation products and sequestering of spermine. Acidification of the seminal plasma impairs sperm motility and also inhibits most antioxidant enzymes, exacerbating the accumulation of reactive oxygen species and the resultant lowering of pH.

  13. The self assembly of thymine at Au(110)/liquid interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Molina Contreras, J.R. [Departamento de Ingenieria Electrica y Electronica, Instituto Tecnologico de Aguascalientes, Mexico (Mexico); Smith, C.I.; Bowfield, A.; Weightman, P. [Physics Department, University of Liverpool (United Kingdom); Tillner, F. [Fachbereich Physik, Universitaet Konstanz (Germany)

    2012-06-15

    We show that thymine self-assembles into an ordered structure when adsorbed at a Au(110)/liquid interface. Reflection anisotropy spectroscopy (RAS) shows that as found for cytosine and adenine the adsorbed thymine molecules are oriented essentially vertically on the Au(110) surface with the molecule aligned along one of the principal axes of the Au(110) surface. Simulations of the RA spectra to an empirical model indicates that as found for adsorbed cytosine and adenine, thymine is aligned along the [1 anti 10] direction on the Au(110) surface. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  14. Resolution of overlapping skin auto-fluorescence for development of non-invasive applications

    Science.gov (United States)

    Su, Yu-Zheng; Lin, Li-Wu; Chen, Chuen-Yau; Hung, Min-Wei; Huang, Kuo-Cheng

    2010-08-01

    Skin auto-fluorescence spectra can provide useful biological information, but the obtained spectrum is overlapped and is difficult to distinguish each contributed component. We applied the genetic algorithm to decompose the overlapping spectrum. First, we simulate the overlapping spectral to confirm our feasible algorithm. The skin auto-fluorescence spectra were obtained from the normal human skin with 337 nm excitation light source. The nicotinamide adenine dinucleotid (NADH) and flavin adenine dinucleotide (FAD) are accurately decomposed and demonstrated. The developed algorithm can be widely applied to achieve qualitative and quantitative analysis for overlapping spectra.

  15. Procedure for studying population genetic aspects of marine organisms using biochemical techniques

    Digital Repository Service at National Institute of Oceanography (India)

    Menezes, M.R.

    .1.1.44); and general protein (PROT). Staining procedures ofenzymes and proteins (Menezes and Taniguchi, 1988) 1. NADP+ dependent Each mixture ofsubstrate staining solution is added with: Nicotinamide-adenine dinucleotide phosphate (NADP) 6mg Phenazine methosulphate... is added with: Nicotinamide-adenine dinucleotide (NAD) 6mg Phenazine methosulphate (PMS) 1mg 189 NBDBlDBTSponsored TraJnbrion T/UU)nOlrlJ, Genet/cs IUld Gene BanJdni ofCoastaJ and Marine BlorDO,m:es, elF£, MwnbaI --Nitro blue tetrazolium (NBT) of 1...

  16. Dissecting direct and indirect readout of cAMP receptor protein DNA binding using an inosine and 2,6-diaminopurine in vitro selection system

    DEFF Research Database (Denmark)

    Lindemose, Søren; Nielsen, Peter E.; Møllegaard, Niels Erik

    2008-01-01

    random library of DNA-binding sites containing inosine (I) and 2,6-diaminopurine (D) instead of guanine and adenine, respectively. Accordingly, the DNA helix minor groove is structurally altered due to the 'transfer' of the 2-amino group of guanine (now I) to adenine (now D), whereas the major groove is...... functionally intact. The majority of the selected sites contain the natural consensus sequence TGTGAN(6)TCACA (i.e. TITIDN(6)TCDCD). Thus, direct readout of the consensus sequence is independent of minor groove conformation. Consequently, the indirect readout known to occur in the TG/CA base pair step (primary...

  17. Determination of nucleosides in Cordyceps sinensis and Ganoderma lucidum by high performance liquid chromatography method

    Directory of Open Access Journals (Sweden)

    Masood Shah Khan

    2015-01-01

    Full Text Available Background: Nucleosides are supportive in the regulation and modulation of various physiological processes in body, they acts as precursors in nucleic acid synthesis, enhance immune response, help in absorption of iron and influence the metabolism of fatty acids. Cordyceps sinensis and Ganoderma lucidum are well-known for its use in traditional medicine of China, Nepal and India. They are rich in nucleosides such as adenine, adenosine, cordycepin, etc. Hence, a simple, economic and accurate high-performance liquid chromatography (HPLC analytical method was proposed for determination of adenine and adenosine for the quality control of plants. Materials and Methods: Chromatographic experiments were conducted on YL9100 HPLC system (South Korea. Reversed-phase chromatography was performed on a C18 column with methanol and dihydrogen phosphate as the mobile phase in isocratic elution method at a flow rate of 1.0 mL/min. Detection was carried out at 254 nm, which gives a sharp peak of adenine and adenosine at a retention time of 6.53 ± 0.02 min and 12.41 ± 0.02, respectively. Results and Discussion: Linear regression analysis data for the calibration plot showed a good linear relationship between response and concentration in the range of 25–200 µg/mL for adenosine and 100–800 µg/mL for adenine with regression coefficient of 0.999 and 0.996, respectively. The adenine was found 0.16% and 0.71% w/w in G. lucidum and in C. sinensis, respectively, and adenosine was found to be 0.14% w/w in G. lucidum whereas absent in C. sinensis. Conclusion: The developed HPLC method for the quantification of adenosine and adenine can be used for the quality control and standardization of crude drug and for the different herbal formulations, in which adenine and adenosine are present as major constituents. The wide linearity range, sensitivity, accuracy, and simple mobile phase imply the method is suitable for routine quantification of adenosine and adenine with

  18. Selective killing of tumors deficient in methylthioadenosine phosphorylase: a novel strategy.

    Directory of Open Access Journals (Sweden)

    Martin Lubin

    Full Text Available BACKGROUND: The gene for methylthioadenosine phosphorylase (MTAP lies on 9p21, close to the gene CDKN2A that encodes the tumor suppressor proteins p16 and p14ARF. MTAP and CDKN2A are homozygously co-deleted, with a frequency of 35 to 70%, in lung and pancreatic cancer, glioblastoma, osteosarcoma, soft-tissue sarcoma, mesothelioma, and T-cell acute lymphoblastic leukemia. In normal cells, but not in tumor cells lacking MTAP, MTAP cleaves the natural substrate, 5'-deoxy-5'-methylthioadenosine (MTA, to adenine and 5-methylthioribose-1-phosphate (MTR-1-P, which are then converted to adenine nucleotides and methionine. This distinct difference between normal MTAP-positive cells and tumor MTAP-negative cells led to several proposals for therapy. We offer a novel strategy in which both MTA and a toxic adenine analog, such as 2,6-diaminopurine (DAP, 6-methylpurine (MeP, or 2-fluoroadenine (F-Ade, are administered. In MTAP-positive cells, abundant adenine, generated from supplied MTA, competitively blocks the conversion of an analog, by adenine phosphoribosyltransferase (APRT, to its active nucleotide form. In MTAP-negative tumor cells, the supplied MTA cannot generate adenine; hence conversion of the analog is not blocked. PRINCIPAL FINDINGS: We show that this combination treatment--adenine analog plus MTA--kills MTAP-negative A549 lung tumor cells, while MTAP-positive human fibroblasts (HF are protected. In co-cultures of the breast tumor cell line, MCF-7, and HF cells, MCF-7 is inhibited or killed, while HF cells proliferate robustly. 5-Fluorouracil (5-FU and 6-thioguanine (6-TG may also be used with our strategy. Though neither analog is activated by APRT, in MTAP-positive cells, adenine produced from supplied MTA blocks conversion of 5-FU and 6-TG to their toxic nucleotide forms by competing for 5-phosphoribosyl-1-pyrophosphate (PRPP. The combination of MTA with 5-FU or 6-TG, in the treatment of MTAP-negative tumors, may produce a significantly

  19. Roles for Dam methylation in bacterial chromosome replication

    DEFF Research Database (Denmark)

    Charbon, Godefroid; Koch, Birgit; Skovgaard, Ole;

    GATC sequences in the DNA of Escherichia coli and related species are methylated at the adenine residue by DNA adenine methyltransferase (DamMT). These methylated residues and/or the level of DamMT influence initiation of chromosome replication from the replication origin, oriC, which contain...... an over-representation of GATC sites, in at least two ways. First, full methylation of oriC promotes duplex opening and hence certain oriC mutants are dependent on Dam methylation for initiation. Second, newly replicated and hemimethylated origins, are bound by SeqA (‘sequestered’) and remain inactive...

  20. On-line measurements of oscillating mitochondrial membrane potential in glucose-fermenting Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Andersen, Ann Zahle; Poulsen, Allan K; Olsen, Lars Folke;

    2007-01-01

    We employed the fluorescent cyanine dye DiOC(2)(3) to measure membrane potential in semi-anaerobic yeast cells under conditions where glycolysis was oscillating. Oscillations in glycolysis were studied by means of the naturally abundant nicotinamide adenine dinucleotide (NADH). We found that the ......We employed the fluorescent cyanine dye DiOC(2)(3) to measure membrane potential in semi-anaerobic yeast cells under conditions where glycolysis was oscillating. Oscillations in glycolysis were studied by means of the naturally abundant nicotinamide adenine dinucleotide (NADH). We found...

  1. Characterization of genetic miscoding lesions caused by postmortem damage

    DEFF Research Database (Denmark)

    Gilbert, M Thomas P; Hansen, Anders J; Willerslev, Eske;

    2002-01-01

    " (cytosine-->thymine/guanine-->adenine). Single-primer extension PCR and enzymatic digestion with uracil-N-glycosylase confirm that each of these groups of transitions result from a single event, the deamination of adenine to hypoxanthine, and cytosine to uracil, respectively. The predominant form...... of detected jumping-PCR artifacts by up to 80%. No bias toward H-strand-specific damage events is noted within the hypervariable 1 region of human mitochondria, suggesting the rapid postmortem degradation of the secondary displacement (D-loop) H strand. The data also indicate that, as damage increases within...

  2. Dependence of surface-enhanced Raman scattering from Calf thymus DNA on anions

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Dependence of surface-enhanced Raman scattering (SERS) from Calf thymus DNA on anions is investigated.With the silver colloid,the bands at 732,960 and 1333 cm-1 for adenine (A),1466 cm-1 for deoxyribose,and 1652 cm-1 for the C=O group of thymine (T) are observably enhanced.With the presence of the Cl- or SO42- anions,the bands at 732 and 1326/1329 cm-1 for the symmetric stretching and skeletal vibrational modes of adenine (A) are dramatically enhanced,and the enhancement effect with the SO24- ion is more than that with the Cl- ion.The experimental results show that the DNA molecule can be adsorbed on the silver colloid particles through the C6N and N7 of adenine (A),the C=O of thymine (T) and deoxyribose.Moreover,the formed hydrogen bonding of the Cl- or S2O4- ions to the C6NH2 group of adenine (A) can induce larger C6N electronegativity,which is favor for the C6N/N7 cooperative adsorption on the (Ag)+n colloid particles.

  3. Actinomyces and Nocardia Infections in Chronic Granulomatous Disease

    OpenAIRE

    Shahindokht Bassiri-Jahromi; Aida Doostkam

    2011-01-01

    Objective : Chronic granulomatous disease (CGD) is an inherited disorder of the Nicotinamide adenine dinucleotide phosphate reduced oxidase complex characterized by recurrent bacterial and fungal infections. Disseminated infection by combination of opportunistic agents is being increasingly reported in CGD patients. We presented in the retrospective review of medical records, the etiology, presentation, clinical characteristics the infections detected, predisposing condition and outcome of no...

  4. Design and synthesis of ATP-based nucleotide analogues and profiling of nucleotide-binding proteins

    NARCIS (Netherlands)

    Wolters, Justina. C.; Roelfes, Johannes; Poolman, Bert

    2011-01-01

    Two nucleotide-based probes were designed and synthesized in order to enrich samples for specific classes of proteins by affinity-based protein profiling. We focused on the profiling of adenine nucleotide-binding proteins. Two properties were considered in the design of the probes: the bait needs to

  5. Pleiotropic effects of the sirtuin inhibitor sirtinol involves concentration-dependent modulation of multiple nuclear receptor-mediated pathways in the androgen-responsive prostate cancer cell LNCaP

    Science.gov (United States)

    Sirtinol, a purported specific inhibitor of the nicotinamide adenine dinucleotide (NAD)-dependent type III histone deacetylase (also known as sirtuin), has been used extensively to identify chemopreventive/chemotherapeutic agents that modulate the activity of this group of enzymes. However, the mole...

  6. Nucleobase assemblies supported by uranyl cation coordination and other non-covalent interactions

    Indian Academy of Sciences (India)

    Jitendra Kumar; Sandeep Verma

    2011-11-01

    We describe synthesis and solid state structural description of uranyl complexes of carboxylate functionalized adenine and uracil derivatives. The metal coordination through carboxylate pendant leads to the formation of dimeric assemblies, whereas the directional nature of hydrogen bonding interaction supported by nucleobases and aqua ligands, result in the generation of complex 3-D architectures containing embedded nucleobase ribbons.

  7. Theoretical Studies of Chemical Reactions following Electronic Excitation

    Science.gov (United States)

    Chaban, Galina M.

    2003-01-01

    The use of multi-configurational wave functions is demonstrated for several processes: tautomerization reactions in the ground and excited states of the DNA base adenine, dissociation of glycine molecule after electronic excitation, and decomposition/deformation of novel rare gas molecules HRgF. These processes involve bond brealung/formation and require multi-configurational approaches that include dynamic correlation.

  8. Thiamin and riboflavin vitamers in human milk: effects of lipid-based nutrient supplementation and stage of lactation on vitamer secretion and contributions to total vitamin content

    Science.gov (United States)

    While thiamin and riboflavin in breast milk have been analyzed for over 50 years, less attention has been given to the different forms of each vitamin. Thiamin-monophosphate (TMP) and free thiamin contribute to total thiamin content; flavin adenine-dinucleotide (FAD) and free riboflavin are the main...

  9. An improved red blood cell additive solution maintains 2,3-diphosphoglycerate and adenosine triphosphate levels by an enhancing effect on phosphofructokinase activity during cold storage

    NARCIS (Netherlands)

    P. Burger; H. Korsten; D. de Korte; E. Rombout; R. van Bruggen; A.J. Verhoeven

    2010-01-01

    BACKGROUND: Current additive solutions (ASs) for red blood cells (RBCs) do not maintain constant 2,3-diphosphoglycerate (DPG) and adenosine triphosphate (ATP) levels during cold storage We have previously shown that with a new AS called phosphate-adenine-glucose-guanosine-gluconate-mannitol (PAGGGM)

  10. Reversible resolution of flavin and pterin cofactors of His-tagged Escherichia coli DNA photolyse.

    NARCIS (Netherlands)

    Xu, L.; Zhang, D.; Mu, W.; Berkel, van W.J.H.; Luo, Z.

    2006-01-01

    Escherichia coli photolyase catalyzes the repair of cyclobutane pyrimidine dimers (CPD) in DNA under near UV/blue-light irradiation. The enzyme contains flavin adenine dinucleotide (FAD) and methenyltetrahydrofolate (MTHF) as noncovalently bound light sensing cofactors. To study the apoprotein-chrom

  11. Deciphering the four-letter code : The genetic basis of complex traits and common disease

    NARCIS (Netherlands)

    Pulit, S.L.

    2016-01-01

    Deoxyribonucleic acid (DNA) is made up of four bases: adenine (A), cytosine (C), guanine (G), and thymine (T). Assembled in a strategic fashion, these bases code for the unique genomes of all walks of life, from viruses, to rodents, to primates. The human genome, mapped completely for the first time

  12. Purine Bases in Blood Plasma of Patients with Chronic Pulmonary Diseases

    Directory of Open Access Journals (Sweden)

    Larissa E. Muravluyova

    2012-09-01

    Full Text Available The article is focused on the study of purine bases and intermediates of purine catabolism in plasma of patients with chronic obstructive bronchitis and idiopathic interstitial pneumonia. Decrease of adenine and hypoxantine in plasma of patients with idiopathic interstitial pneumonia was registered. Increase of guanine in plasma of patients with chronic obstructive pulmonary disease was established.

  13. Efficient regeneration of NADPH in a 3-enzyme cascade reaction by in situ generation of glucose 6-phosphate from glucose and pyrophosphate

    NARCIS (Netherlands)

    A.F. Hartog; T. van Herk; R. Wever

    2011-01-01

    We report here a promising method to regenerate NADPH (nicotinamide adenine dinucleotide phosphate) using the intermediate formation of glucose 6-phosphate (G6P) from glucose and pyrophosphate (PPi) catalyzed by the acid phosphatase from Shigella flexneri (PhoN-Sf). The G6P formed is used in turn by

  14. Interaction of ADP, atractyloside, and gummiferin on the ADP translocase of the inner mitochondrial membrane

    Energy Technology Data Exchange (ETDEWEB)

    Vignais, P.V.; Vignais, P.M.; Defaye, G.; Lauquin, G.; Doussiere, J.; Chabert, J.; Brandolin, G.

    1972-05-01

    From international conference on mechanism in bioenergetica; Bari, Italy (1 May 1972). Two specific inhibitors of the adenine nucleotide translocation, gummiferin (GUM), identified to 4-carboxyatractyloside and atractyloside (ATR), were labeled with /sup 35/S and their binding properties to whole mitochondria and inner mitochondrial membrane vesicles used to monitor changes of membrane conformation induced by ADP. (auth)

  15. Bacillus subtilis guanine deaminase is encoded by the yknA gene and is induced during growth with purines as the nitrogen source

    DEFF Research Database (Denmark)

    Nygaard, Per; Bedsted, Søren; Andersen, Kasper A.K.;

    2000-01-01

    Bacillus subtilis can utilize the purine bases adenine, hypoxanthine and xanthine as nitrogen sources. The utilization of guanine as a nitrogen source is reported here. The first step is the deamination of guanine to xanthine catalysed by guanine deaminase (GDEase). To isolate mutants defective in...

  16. Hydrogen bonding versus stacking stabilization by modified nucleobases incorporated in PNA. DNA duplexes

    DEFF Research Database (Denmark)

    Sen, Anjana; Nielsen, Peter E

    2009-01-01

    The effects of incorporation of the modified nucleobases, 2,6-diaminopurine (D) (substituting for adenine) and 7-chloro-1,8-naphthyridin-2-(1H)-one (bicyclic thymine, bT) (substituting for thymine), that stabilize PNA.DNA duplex formation by increasing hydrogen bonding and/or base pair stacking...

  17. Requirement for a conserved, tertiary interaction in the core of 23S ribosomal RNA

    DEFF Research Database (Denmark)

    Aagaard, C; Douthwaite, S

    1994-01-01

    A putative base-pairing interaction that determines the folding of the central region of 23S rRNA has been investigated by mutagenesis. Each of the possible base substitutions has been made at the phylogenetically covariant positions adenine-1262 (A1262) and U2017 in Escherichia coli 23S rRNA. Ev...

  18. Immunomodulating effect of blood transfusion: is storage time important?

    DEFF Research Database (Denmark)

    Mynster, T; Dybkjoer, E; Kronborg, Gitte;

    1998-01-01

    OBJECTIVES: TNF-alpha and IL-2 are important cytokines in macrophage and T-lymphocyte activity against infection and dissemination of malignant cells. We studied the influence of supernatants from stored whole blood and buffy-coat-depleted SAGM (saline, adenine, glucose and mannitol) blood in sti...

  19. Excitation Spectra of Nucleobases with Multiconfigurational Density Functional Theory

    DEFF Research Database (Denmark)

    Hubert, Mickaël; Jensen, Hans Jørgen Aa; Hedegård, Erik D.

    2016-01-01

    thymine, uracil, cytosine, and adenine, using a hybrid between complete active space self-consistent field (CASSCF) and DFT methods. The method is based on range separation, thereby avoiding all double-counting of electron correlation and is denoted long-range CASSCF short-range DFT (CAS-srDFT). Using...

  20. Saccharomyces cerevisiae engineered for xylose metabolism requires gluconeogenesis and the oxidative branch of the pentose phosphate pathway for aerobic xylose assimilation

    Science.gov (United States)

    Saccharomyces strains engineered to ferment xylose using Scheffersomyces stipitis xylose reductase (XR) and xylitol dehydrogenase (XDH) genes appear to be limited by metabolic imbalances due to differing cofactor specificities of XR and XDH. The S. stipitis XR, which uses nicotinamide adenine dinucl...

  1. Ketogenesis in rat-liver mitochondria: Stimulation by palmityl-coenzyme A

    NARCIS (Netherlands)

    Vaartjes, W.J.; Lopes-Cardozo, M.; Bergh, S.G. van den

    1972-01-01

    It is well-known that the movement of adenine nucleotides (AdN) across the inner mitochondrial membrane is markedly decreased both by unsaturated and by saturated long-chain fatty acids. A similar effect is displayed by palmityl-CoA as demonstrated recently with isolated mitochondria of rat heart an

  2. Functioning of oxidative phosphorylation in liver mitochondria of high-fat diet fed rats

    NARCIS (Netherlands)

    Ciapaite, Jolita; Bakker, Stephan J. L.; Van Eikenhorst, Gerco; Wagner, Marijke J.; Teerlink, Tom; Schalkwijk, Casper G.; Fodor, Mariann; Ouwens, D. Margriet; Diamant, Michaela; Heine, Robert J.; Westerhoff, Hans V.; Krab, Klaas

    2007-01-01

    We proposed that inhibition of mitochondrial adenine nucleotide translocator (ANT) by long chain acyl-CoA (LCAC) underlies the mechanism associating obesity and type 2 diabetes. Here we test that after long-term exposure to a higb-fat diet (HFD): (i) there is no adaptation of the mitochondrial compa

  3. Growth hormone dose in growth hormone-deficient adults is not associated with IGF-1 gene polymorphisms

    NARCIS (Netherlands)

    S. Meyer; S. Schaefer (Stephan); D. Ivan (Diana); L. Stolk (Lisette); P.P. Arp (Pascal); A.G. Uitterlinden (André); P.P. Nawroth (Peter); U. Plöckinger (Ursula); G.K. Stalla (Günter); U. Tuschy (Ulrich); M.M. Weber (Matthias); W.J. Weise (Wolfgang); A. Pfützner (Andreas); P. Kann (P.)

    2009-01-01

    textabstractAims: Several SNPs and a microsatellite cytosine-adenine repeat promoter polymorphisms of the IGF-1 gene have been reported to be associated with circulating IGF-1 serum concentrations. Variance in IGF-1 concentrations due to genetic variations may affect different response to growth hor

  4. Ion interaction with biomolecular systems and the effect of the environment

    International Nuclear Information System (INIS)

    To fully understand the mechanisms of radiation damage in living tissues, a detailed knowledge of the processes occurring at the molecular level is needed. In the gas phase, most of the investigations concerning the ionization and fragmentation of biologically relevant molecular systems are performed with isolated molecules. The importance of such studies is limited to the intrinsic properties of these molecules because of the lack of a chemical environment. To probe the effect of such an environment on the behavior of small biomolecules under irradiation, the molecules (α-amino acids, adenine) were embedded into clusters. The present results, obtained with multiply charged ions, clearly indicate the protective role of the clusters since the total fragmentation yield is reduced for all systems. The surrounding molecules allow for a redistribution of the excess energy and of the charge within the cluster. In the case of adenine clusters, a new fragmentation channel is identified. Moreover, for hydrated adenine clusters, low-energy ion induced chemical reactions are observed, namely the proton transfer from the water cluster to the adenine molecule.

  5. Hypermutation in the E2 gene of human papillomavirus type 16 in cervical intraepithelial neoplasia.

    Science.gov (United States)

    Kukimoto, Iwao; Mori, Seiichiro; Aoyama, Satoru; Wakae, Kousho; Muramatsu, Masamichi; Kondo, Kazunari

    2015-10-01

    Persistent infection with oncogenic human papillomavirus (HPV) causes cervical cancer. However, viral genetic changes during cervical carcinogenesis are not fully understood. Recent studies have revealed the presence of adenine/thymine-clustered hypermutation in the long control region of the HPV16 genome in cervical intraepithelial neoplasia (CIN) lesions, and suggested that apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like (APOBEC) proteins, which play a key role in innate immunity against retroviral infection, potentially introduce such hypermutation. This study reports for the first time the detection of adenine/thymine-clustered hypermutation in the E2 gene of HPV16 isolated from clinical specimens with low- and high-grade CIN lesions (CIN1/3). Differential DNA denaturation PCR, which utilizes lower denaturation temperatures to selectively amplify adenine/thymine-rich DNA, identified clusters of adenine/thymine mutations in the E2 gene in 4 of 11 CIN1 (36.4%), and 6 of 27 CIN3 (22.2%) samples. Interestingly, the number of mutations per sample was higher in CIN3 than in CIN1. Although the relevance of E2 hypermutation in cervical carcinogenesis remains unclear, the observed hypermutation patterns strongly imply involvement of APOBEC3 proteins in editing the HPV16 genome during natural viral infection. PMID:25914233

  6. Detection of ATP and NADH: A Bioluminescent Experience.

    Science.gov (United States)

    Selig, Ted C.; And Others

    1984-01-01

    Described is a bioluminescent assay for adenosine triphosphate (ATP) and reduced nicotineamide-adenine dinucleotide (NADH) that meets the requirements of an undergraduate biochemistry laboratory course. The 3-hour experiment provides students with experience in bioluminescence and analytical biochemistry yet requires limited instrumentation,…

  7. Protein Modification: Bacterial Effectors Rewrite the Rules of Ubiquitylation.

    Science.gov (United States)

    Berk, Jason M; Hochstrasser, Mark

    2016-07-11

    A family of virulence factors from the bacterial pathogen Legionella pneumophila has been discovered to modify human Rab GTPases with ubiquitin. Surprisingly, this modification occurs via a non-canonical mechanism that uses nicotinamide adenine dinucleotide as a cofactor. PMID:27404243

  8. KIDNEY AND URINARY TRACT

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Objective: To study the relationship between insulin-like growth factor-1 (IGF-1), basic fibroblast growth factor (bFGF) and the pathological changes in uric acid nephropathy. Methods: In the pathological progress of 30 uric acid nephropathy rats induced by adenine, the expression of IGF-lmRNA,

  9. P-hydroxybenzoate hydroxylase. Determination of the amino acid sequence and its integration with the crystal structure.

    NARCIS (Netherlands)

    Hofsteenge, Jan

    1981-01-01

    Het enzym p-hydroxybenzoaat hydroxylase katalyseert een belangrijke reaktie in de metabolische weg voor de afbraak van aromatische verbindingen (B-ketoadipaat route). […] Het enzym bevat flavine adenine dinucleotide (FAD). De flavine wordt tijdens de reaktie gereduceerd door NADPH, waarna het een co

  10. Skeletal muscle contractile performance and ADP accumulation in adenylate kinase-deficient mice

    NARCIS (Netherlands)

    Hancock, C.R.; Janssen, E.E.W.; Terjung, R.L.

    2005-01-01

    The production of AMP by adenylate kinase (AK) and subsequent deamination by AMP deaminase limits ADP accumulation during conditions of high-energy demand in skeletal muscle. The goal of this study was to investigate the consequences of AK deficiency (-/-) on adenine nucleotide management and whole

  11. Often Ignored Facts about the Control of the 2-Oxoglutarate Dehydrogenase Complex

    Science.gov (United States)

    Strumilo, Slawomir

    2005-01-01

    Information about the control of the activity of the 2-oxoglutarate dehydrogenase complex (OGDHC), a key enzyme in the citric acid cycle, is not well covered in the biochemical education literature, especially as it concerns the allosteric regulation of OGDHC by adenine nucleotide and ortophosphate. From experimental work published during the last…

  12. Regulation of substrate utilization in the flight muscle of the locust, Locusta migratoria, during flight

    NARCIS (Netherlands)

    Worm, R.A.A.; Beenakkers, A.M.Th.

    1980-01-01

    The concentrations of metabolites involved in carbohydrate metabolizing pathways, of amino acids and adenine nucleotides in the flight muscles of Locusta migratoria were determined during a fligt of 2 hr. During the first 15 min of flight, glycogen and glucose concentrations decreased to reach appro

  13. Nitric oxide synthase in the gill of Atlantic salmon: colocalization with and inhibition of Na+,K+-ATPase

    DEFF Research Database (Denmark)

    Ebbesson, Lars O E; Tipsmark, Christian K; Holmqvist, Bo;

    2005-01-01

    We investigated the relationship between nitric oxide (NO) and Na(+),K(+)-ATPase (NKA) in the gill of anadromous Atlantic salmon. Cells containing NO-producing enzymes were revealed by means of nitric oxide synthase (NOS) immunocytochemistry and nicotinamide adenine dinucleotide phosphate...

  14. Effects of acute and chronic endurance exercise on mitochondrial uncoupling in human skeletal muscle

    DEFF Research Database (Denmark)

    Fernström, Maria; Tonkonogi, Michail; Sahlin, Kent

    2004-01-01

    Mitochondrial proteins such as uncoupling protein 3 (UCP3) and adenine nucleotide translocase (ANT) may mediate back-leakage of protons and serve as uncouplers of oxidative phosphorylation. We hypothesized that UCP3 and ANT increase after prolonged exercise and/or endurance training, resulting...

  15. [Hopping and superexchange mechanisms of charge transport to DNA].

    Science.gov (United States)

    Lakhno, V D; Sultanov, V B

    2003-01-01

    A theory for charge transport in nucleobase sequences was constructed in which the hole migration proceeds via hopping between guanines. Each hop over the adenine-thymine (A-T) bridge connecting neighboring guanines occurs by means of the superexchange mechanism. The experimental data and theoretical results for various types of nucleobase sequences are compared.

  16. Temperature dependence of electronic heat capacity in Holstein model

    CERN Document Server

    Fialko, N S; Lakhno, V D

    2015-01-01

    The dynamics of charge migration was modeled to calculate temperature dependencies of its thermodynamic equilibrium values such as energy and electronic heat capacity in homogeneous adenine fragments. The energy varies from nearly polaron one at T~0 to midpoint of the conductivity band at high temperatures. The peak on the graph of electronic heat capacity is observed at the polaron decay temperature.

  17. Novel molecular insights into the mechanism of GO removal by MutM

    Institute of Scientific and Technical Information of China (English)

    Guo-Min Li

    2010-01-01

    7,8-dihydro-8-oxo-dGuanine (oxoG or GO, see Figure 1A) is one of the most abundant oxidative DNA lesions caused by exposure of DNA to reactive oxygen species. GO is highly mutagenic, frequently leading to G:C to T:A transversion, because it preferentially pairs with adenine (A) during DNA replication.

  18. First-pass metabolism of ethanol in human beings: effect of intravenous infusion of fructose

    DEFF Research Database (Denmark)

    Parlesak, Alexandr; Billinger, MH; Schäfer, C.;

    2004-01-01

    Intravenous infusion of fructose has been shown to enhance reduced form of nicotinamide adenine dinucleotide reoxidation and, thereby, to enhance the metabolism of ethanol. In the current study, the effect of fructose infusion on first-pass metabolism of ethanol was studied in human volunteers...

  19. Environ: E00137 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available E00137 Benincasa seed (JP16) Crude drug Oleic acid [CPD:C00712], Linoleic acid [CPD...:C01595], Adenine [CPD:C00147], Trigonelline [CPD:C01004], Linolenic acid [CPD:C06426 C06427] Benincasa ceri...fera [TAX:102210] Same as: D06767 Cucurbitaceae (cucumber family) Benincasa seed Major component: Trigonelline [CPD:C01004] ...

  20. Efficacy of oral curcuminoid fraction from curcuma xanthorrhiza and curcuminoid cider in high-cholesterol fed rats

    Directory of Open Access Journals (Sweden)

    Flavia Maria Mauren

    2016-01-01

    Abbreviations Used: ROS: Reactive oxygen species, NO: Nitric oxide, NOS: NO synthase, NADPH: Nicotinamide adenine dinucleotide phosphate, CD44: Cluster of differentiation 44, ICAM-1: Intercellular adhesion molecule 1, iNOS: inducible NOS, LOX-1: lectin-like oxidized LDL receptor-1, HMG-CoA: 3-hydroxy-3-methylglutaryl-coenzyme A, 5-HMF: 5-hydroxymethylfurfural, HCD: High-cholesterol diet

  1. Domain V of 23S rRNA contains all the structural elements necessary for recognition by the ErmE methyltransferase

    DEFF Research Database (Denmark)

    Vester, B; Douthwaite, S

    1994-01-01

    The ErmE methyltransferase from the erythromycin-producing actinomycete Saccharopolyspora erythraea dimethylates the N-6 position of adenine 2058 in domain V of 23S rRNA. This modification confers resistance to erythromycin and to other macrolide, lincosamide, and streptogramin B antibiotics. We...

  2. DNA apophotolyase from Anacystis nidulans: 1.8 A structure, 8-HDF reconstitution and X-ray-induced FAD reduction.

    NARCIS (Netherlands)

    R. Kort; H. Komori; S. Adachi; K. Miki; A. Eker

    2004-01-01

    DNA photolyase is a unique flavoenzyme that repairs UV-induced DNA lesions using the energy of visible light. Anacystis nidulans photolyase contains a light-harvesting chromophore, 8-hydroxy-5-deazaflavin (8-HDF), and flavin adenine dinucleotide (FAD) which, in contrast to the 8-HDF chromophore, is

  3. CONTINUOUS MONITORING OF EXTRACELLULAR LACTATE CONCENTRATION BY MICRODIALYSIS LACTOGRAPHY FOR THE STUDY OF RAT MUSCLE METABOLISM INVIVO

    NARCIS (Netherlands)

    DEBOER, J; POSTEMA, F; PLIJTERGROENDIJK, H; KORF, J

    1991-01-01

    A method is described for the measurement and on-line monitoring of muscular extracellular lactate concentration in both anaesthetized and freely moving rats. This method is based on microdialysis sampling and lactic dehydrogenase-catalysed nicotinamide adenine dinucleotide, reduced (NADH)-fluoresce

  4. A density functional for sparse matter

    DEFF Research Database (Denmark)

    Langreth, D.C.; Lundqvist, Bengt; Chakarova-Kack, S.D.;

    2009-01-01

    forces in molecules, to adsorbed molecules, like benzene, naphthalene, phenol and adenine on graphite, alumina and metals, to polymer and carbon nanotube (CNT) crystals, and hydrogen storage in graphite and metal-organic frameworks (MOFs), and to the structure of DNA and of DNA with intercalators...

  5. AcEST: DK945559 [AcEST

    Lifescience Database Archive (English)

    Full Text Available DEC_RHILO Adenine deaminase OS=Rhizobium loti GN=ade ... 34 0.58 sp|O24006|AMP_IMPBA Antimicrobial peptides ...A E DH+GT Sbjct: 222 YASRDLGLP-FHGYVAGGPEDDHEGT 246 >sp|O24006|AMP_IMPBA Antimicrobial peptides OS=Impatiens

  6. Characterizing the intracellular distribution of metabolites in intact Chlamydia-infected cells by Raman and two-photon microscopy.

    Science.gov (United States)

    Szaszák, Márta; Chang, Jiun Chiun; Leng, Weinan; Rupp, Jan; Ojcius, David M; Kelley, Anne Myers

    2013-06-01

    Chlamydia species are obligate intracellular pathogens that proliferate only within infected cells. Currently, there are no known techniques or systems that can probe the spatial distribution of metabolites of interest within intact Chlamydia-infected cells. Here we investigate the ability of Raman microscopy to probe the chemical composition of different compartments (nucleus, inclusion, and cytoplasm) of Chlamydia trachomatis-infected epithelial cells. The overall intensity of the Raman spectrum is greatest in the inclusions and lowest in the cytoplasm in fixed cells. Difference spectra generated by normalizing to the intensity of the strong 1004 cm(-1) phenylalanine line show distinct differences among the three compartments. Most notably, the concentrations of adenine are greater in both the inclusions and the nucleus than in the cytoplasm, as seen by Raman microscopy. The source of the adenine was explored through a complementary approach, using two-photon microscopy imaging. Autofluorescence measurements of living, infected cells show that the adenine-containing molecules, NAD(P)H and FAD, are present mainly in the cytoplasm, suggesting that these molecules are not the source of the additional adenine signal in the nucleus and inclusions. Experiments of infected cells stained with a DNA-binding dye, Hoechst 33258, reveal that most of the DNA is present in the nucleus and the inclusions, suggesting that DNA/RNA is the main source of the additional Raman adenine signal in the nucleus and inclusions. Thus, Raman and two-photon microscopy are among the few non-invasive methods available to investigate cells infected with Chlamydia and, together, should also be useful for studying infection by other intracellular pathogens that survive within intracellular vacuoles.

  7. Isoflurane preserves energy balance in isolated hepatocytes during in vitro anoxia/reoxygenation

    Institute of Scientific and Technical Information of China (English)

    Quan Li; Wei-Feng Yu; Mai-Tao Zhou; Xin Lu; Li-Qun Yang; Ming Zhu; Jian-Gang Song; Jun-Hua Lu

    2005-01-01

    AIM: To investigate the protective effect of isoflurane on energy balance in isolated hepatocytes during in vitro anoxia/reoxygenation, and to compare isoflurane with halothane.METHODS: Hepatocytes freshly isolated from fed rats were suspended in Krebs-Henseleit buffer, and incubated in sealed flasks under O2/CO2 or N2/CO2 (95%/5%, V/V)for 30 or 60 min, followed by 5 or 10 min of reoxygenation,with an added volatile anesthetic or not. ATP, ADP, and adenosine monophosphate in hepatocytes were determined by high performance liquid chromatography, and energy charge was calculated.RESULTS: During 30 min of anoxia, the energy charge and total adenine nucleotide steadily increased with the isoflurane dose from 0 to 2 minimum alveolar anesthetic concentration (MAC), then decreased from 2 to 3 MAC.In short incubations (30-35 min) at 1 MAC isoflurane, energy charge modestly decreased during anoxia, which was partially prevented by isoflurane and completely reversed by reoxygenation, and total adenine nucleotide did not decrease. In long incubations (60-70 min), both energy charge and total adenine nucleotide greatly decreased during anoxia, with partial and no reversal by reoxygenation,respectively. Isoflurane partly prevented decreases in both energy charge and total adenine nucleotide during anoxia and reoxygenation. In addition, 1 MAC isoflurane obviously increased ATP/ADP, which could not be changed by 1MAC halothane.CONCLUSION: Isoflurane partially protects isolated hepatocytes against decreases in both energy charge and total adenine nucleotide during short (reversible) or long (irreversible) anoxia.

  8. Modulation of DNA methylation and gene expression in cultured sycamore cells treated by hypomethylating base analog.

    Science.gov (United States)

    Ngernprasirtsiri, J; Akazawa, T

    1990-12-12

    The selective suppression of photosynthetic genes in both the nuclear and plastid genomes of the nonphotosynthetic white wild-type cell line of sycamore (Acer pseudoplatanus) has been found to be inversely related to the presence of a variety of methylated bases, especially 5-methylcytosine (5-MeCyt) and N6-methyladenine (N6-MeAde), localized in regions of the plastid genome containing silent genes. We used hypomethylating base analogs to manipulate the level of cytosine and adenine methylation in the white cells of sycamore, and examined the effects of changes in methylation on gene expression. Treatment with 5-azacytidine (5-AzaCyd) and N6-benzyladenine (N6-BzlAde) decreased cytosine and adenine methylation. This was accompanied by restoration of transcriptional activity in photosynthetic genes which are usually suppressed. Both 5-MeCyt and N6-MeAde suppressed nuclear gene expression, but only 5-MeCyt suppressed plastid gene expression.

  9. The synthesis of double-headed nucleosides by the CuAAC reaction and their effect in secondary nucleic acid structures

    DEFF Research Database (Denmark)

    Jørgensen, Anna Søndergaard; Shaikh, Khalil Isak; Enderlin, Gerald;

    2011-01-01

    Four double-headed nucleosides were prepared by the CuAAC reaction. Hereby, a triazole-containing linker connects an additional thymine or adenine to the 2´-position of 2´-deoxyuridine, a thymine to the 5´-position of thymidine and a thymine to the 6¢-position of an LNA-thymidine monomer. Whereas...... no conclusive recognition effects of the additional thymines were found when introduced in LNA or at the 5´-position, both thymine and adenine in the 2´-position were found to stabilise three-way junctions in both dsDNA and DNA:RNA contexts and to give cross-strand interactions in a DNA-duplex, when...

  10. Characterization of two-pore channel 2 (TPCN2)-mediated Ca2+ currents in isolated lysosomes.

    Science.gov (United States)

    Schieder, Michael; Rötzer, Katrin; Brüggemann, Andrea; Biel, Martin; Wahl-Schott, Christian A

    2010-07-01

    Two-pore channels (TPCNs) have been proposed to form lysosomal Ca(2+) release channels that are activated by nicotinic acid adenine dinucleotide phosphate. Here, we employ a glass chip-based method to record for the first time nicotinic acid adenine dinucleotide phosphate -dependent currents through a two-pore channel (TPCN2) from intact lysosomes. We show that TPCN2 is a highly selective Ca(2+) channel that is regulated by intralysosomal pH. Using site-directed mutagenesis, we identify an amino acid residue in the putative pore region that is crucial for conferring high Ca(2+) selectivity. Our glass chip-based method will provide electrophysiological access not only to lysosomal TPCN channels but also to a broad range of other intracellular ion channels.

  11. Characterization of Two-pore Channel 2 (TPCN2)-mediated Ca2+ Currents in Isolated Lysosomes*

    Science.gov (United States)

    Schieder, Michael; Rötzer, Katrin; Brüggemann, Andrea; Biel, Martin; Wahl-Schott, Christian A.

    2010-01-01

    Two-pore channels (TPCNs) have been proposed to form lysosomal Ca2+ release channels that are activated by nicotinic acid adenine dinucleotide phosphate. Here, we employ a glass chip-based method to record for the first time nicotinic acid adenine dinucleotide phosphate -dependent currents through a two-pore channel (TPCN2) from intact lysosomes. We show that TPCN2 is a highly selective Ca2+ channel that is regulated by intralysosomal pH. Using site-directed mutagenesis, we identify an amino acid residue in the putative pore region that is crucial for conferring high Ca2+ selectivity. Our glass chip-based method will provide electrophysiological access not only to lysosomal TPCN channels but also to a broad range of other intracellular ion channels. PMID:20495006

  12. A reagentless enzymatic amperometric biosensor using vertically aligned carbon nanofibers (VACNF)

    Energy Technology Data Exchange (ETDEWEB)

    Weeks, Martha L [University of Tennessee, Knoxville (UTK); Rahman, Touhidur [ORNL; Frymier, Paul Dexter [ORNL; Islam, Syed K [University of Tennessee, Knoxville (UTK); McKnight, Timothy E [ORNL

    2008-01-01

    A reagentless amperometric enzymatic biosensor is constructed on a carbon substrate for detection of ethanol. Yeast alcohol dehydrogenase (YADH), an oxidoreductase, and its cofactor nicotinamide adenine dinucleotide (NAD+) are immobilized by adsorption and covalent attachment to the carbon substrate. Carbon nanofibers grown by plasma enhanced chemical vapor deposition (PECVD) are chosen as the electrode material due to their excellent structural and electrical properties. Electrochemical techniques are employed to test the functionality and performance of the biosensor using reduced form of nicotinamide adenine dinucleotide (NADH) which also determines the oxidation peak potential of NADH. Subsequently, amperometric measurements are conducted for detection of ethanol to determine the electrical current response due to the increase in analyte concentration. The detection range, storage stability, reusability, and response time of the biosensor are also examined.

  13. Electrochemical determination of the anticancer drug taxol at a ds-DNA modified pencil-graphite electrode and its application as a label-free electrochemical biosensor.

    Science.gov (United States)

    Tajik, Somayeh; Taher, Mohammad Ali; Beitollahi, Hadi; Torkzadeh-Mahani, Mosoud

    2015-03-01

    In this study a novel biosensor for determination of taxol is described. The interaction of taxol with salmon-sperm double-stranded DNA (ds-DNA) based on the decreasing of the oxidation signals of guanine and adenine bases was studied electrochemically with a pencil-graphite electrode (PGE) using a differential pulse voltammetry (DPV) method. The decreases in the intensity of the guanine and adenine oxidation signals after interaction with taxol were used as indicator signals for the sensitive determination of taxol. DPV exhibits a linear dynamic range of 2.0×10(-7)-1.0×10(-5) M for taxol with a detection limit of 8.0×10(-8) M. Finally, this modified electrode was used for determination of taxol in some real samples.

  14. Critical appraisal of excited state nonadiabatic dynamics simulations of 9H-adeninea)

    Science.gov (United States)

    Barbatti, Mario; Lan, Zhenggang; Crespo-Otero, Rachel; Szymczak, Jaroslaw J.; Lischka, Hans; Thiel, Walter

    2012-12-01

    In spite of the importance of nonadiabatic dynamics simulations for the understanding of ultrafast photo-induced phenomena, simulations based on different methodologies have often led to contradictory results. In this work, we proceed through a comprehensive investigation of on-the-fly surface-hopping simulations of 9H-adenine in the gas phase using different electronic structure theories (ab initio, semi-empirical, and density functional methods). Simulations that employ ab initio and semi-empirical multireference configuration interaction methods predict the experimentally observed ultrafast deactivation of 9H-adenine with similar time scales, however, through different internal conversion channels. Simulations based on time-dependent density functional theory with six different hybrid and range-corrected functionals fail to predict the ultrafast deactivation. The origin of these differences is analyzed by systematic calculations of the relevant reaction pathways, which show that these discrepancies can always be traced back to topographical features of the underlying potential energy surfaces.

  15. Orofacial inflammatory pain affects the expression of MT1 and NADPH-d in rat caudal spinal trigeminal nucleus and trigeminal ganglion

    Institute of Scientific and Technical Information of China (English)

    Fang Huang; Hongwen He; Wenguo Fan; Yongliang Liu; Hongyu Zhou; Bin Cheng

    2013-01-01

    Very little is known about the role of melatonin in the trigeminal system, including the function of melatonin receptor 1. In the present study, adult rats were injected with formaldehyde into the right vibrissae pad to establish a model of orofacial inflammatory pain. The distribution of melatonin re-ceptor 1 and nicotinamide adenine dinucleotide phosphate diaphorase in the caudal spinal minal nucleus and trigeminal ganglion was determined with immunohistochemistry and mistry. The results show that there are significant differences in melatonin receptor 1 expression and nicotinamide adenine dinucleotide phosphate diaphorase expression in the trigeminal ganglia and caudal spinal nucleus during the early stage of orofacial inflammatory pain. Our findings sug-gest that when melatonin receptor 1 expression in the caudal spinal nucleus is significantly reduced, melatonin’s regulatory effect on pain is attenuated.

  16. Nanostructured films of metal particles obtained by laser ablation

    Energy Technology Data Exchange (ETDEWEB)

    Muniz-Miranda, M., E-mail: muniz@unifi.it [Dipartimento di Chimica “U. Schiff”, Università di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino (Italy); Gellini, C. [Dipartimento di Chimica “U. Schiff”, Università di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino (Italy); Giorgetti, E.; Margheri, G.; Marsili, P. [Istituto Sistemi Complessi (CNR), Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy); Lascialfari, L.; Becucci, L. [Dipartimento di Chimica “U. Schiff”, Università di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino (Italy); Trigari, S. [Istituto Sistemi Complessi (CNR), Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy); Giammanco, F. [Dipartimento di Fisica “E. Fermi”, Università di Pisa, Largo Pontecorvo 3, 56127 Pisa (Italy)

    2013-09-30

    Colloidal dispersions of silver and gold nanoparticles were obtained in pure water by ablation with nanosecond pulsed laser. Then, by filtration of the metal particles on alumina, we fabricated nanostructured films, whose surface morphology was examined by atomic force microscopy (AFM) and related to surface-enhanced Raman scattering (SERS) after adsorption of adenine. - Highlights: • Ag and Au colloidal nanoparticles were obtained by laser ablation. • Nanostructured Ag and Au films were fabricated by filtration of metal nanoparticles. • Surface morphology of metal films was investigated by atomic force microscopy. • Surface-enhanced Raman spectra (SERS) of adenine on metal films were obtained. • SERS enhancements were related to the surface roughness of the metal films.

  17. A quantum theoretical study of reactions of methyldiazonium ion with DNA base pairs

    Science.gov (United States)

    Shukla, P. K.; Ganapathy, Vinay; Mishra, P. C.

    2011-09-01

    Methylation of the DNA bases in the Watson-Crick GC and AT base pairs by the methyldiazonium ion was investigated employing density functional and second order Møller-Plesset (MP2) perturbation theories. Methylation at the N3, N7 and O6 sites of guanine, N1, N3 and N7 sites of adenine, O2 and N3 sites of cytosine and the O2 and O4 sites of thymine were considered. The computed reactivities for methylation follow the order N7(guanine) > N3(adenine) > O6(guanine) which is in agreement with experiment. The base pairing in DNA is found to play a significant role with regard to reactivities of the different sites.

  18. [Niacin deficiency and cutaneous immunity].

    Science.gov (United States)

    Ikenouchi-Sugita, Atsuko; Sugita, Kazunari

    2015-01-01

    Niacin, also known as vitamin B3, is required for the synthesis of coenzymes, nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP). Niacin binds with G protein-coupled receptor (GPR) 109A on cutaneous Langerhans cells and causes vasodilation with flushing in head and neck area. Niacin deficiency due to excessive alcohol consumption, certain drugs or inadequate uptake in diet causes pellagra, a photosensitivity dermatitis. Recently several studies have revealed the mechanism of photosensitivity in niacin deficiency, which may pave a way for new therapeutic approaches. The expression level of prostaglandin E synthase (PTGES) is up-regulated in the skin of both pellagra patients and niacin deficient pellagra mouse models. In addition, pellagra is mediated through prostaglandin E₂-EP4 (PGE₂-EP4) signaling via reactive oxygen species (ROS) production in keratinocytes. In this article, we have reviewed the role of niacin in immunity and the mechanism of niacin deficiency-induced photosensitivity. PMID:25765687

  19. Analysis of serum from type II diabetes mellitus and diabetic complication using surface-enhanced Raman spectra (SERS)

    Science.gov (United States)

    Han, H. W.; Yan, X. L.; Dong, R. X.; Ban, G.; Li, K.

    2009-03-01

    In this paper, we show surface-enhanced Raman spectra (SERS) of serums from type II diabetes mellitus and diabetic complication (coronary disease, glaucoma and cerebral infarction), and analyze the SERS through the multivariate statistical methods of principal component analysis (PCA). In particular, we find that there exist many adenines in these serums, which maybe come from DNA (RNA) damage. The relative intensity of the band at 725±2 cm-1 assigned to adenine is higher for patients than for the healthy volunteers; therefore, it can be used as an important ‘fingerprint’ in order to diagnose these diseases. It is also shown that serums from type II diabetes mellitus group, diabetic complication group and healthy volunteers group can be discriminated by PCA.

  20. Nonlinear optical molecular imaging enables metabolic redox sensing in tissue-engineered constructs

    Science.gov (United States)

    Chen, Leng-Chun; Lloyd, William R.; Wilson, Robert H.; Kuo, Shiuhyang; Marcelo, Cynthia L.; Feinberg, Stephen E.; Mycek, Mary-Ann

    2011-07-01

    Tissue-engineered constructs require noninvasive monitoring of cellular viability prior to implantation. In a preclinical study on human Ex Vivo Produced Oral Mucosa Equivalent (EVPOME) constructs, nonlinear optical molecular imaging was employed to extract morphological and functional information from intact constructs. Multiphoton excitation fluorescence images were acquired using endogenous fluorescence from cellular nicotinamide adenine dinucleotide phosphate [NAD(P)H] and flavin adenine dinucleotide (FAD). The images were analyzed to report quantitatively on tissue structure and metabolism (redox ratio). Both thickness variations over time and cell distribution variations with depth were identified, while changes in redox were quantified. Our results show that nonlinear optical molecular imaging has the potential to visualize and quantitatively monitor the growth and viability of a tissue-engineered construct over time.

  1. Sensing cell metabolism by time-resolved autofluorescence

    Science.gov (United States)

    Wu, Yicong; Zheng, Wei; Qu, Jianan Y.

    2006-11-01

    We built a time-resolved confocal fluorescence spectroscopy system equipped with the multichannel time-correlated single-photon-counting technique. The instrument provides a unique approach to study the fluorescence sensing of cell metabolism via analysis of the wavelength- and time-resolved intracellular autofluorescence. The experiments on monolayered cell cultures show that with UV excitation at 365 nm the time-resolved autofluorescence decays, dominated by free-bound reduced nicotinamide adenine dinucleotide signals, are sensitive indicators for cell metabolism. However, the sensitivity decreases with the increase of excitation wavelength possibly due to the interference from free-bound flavin adenine dinucleotide fluorescence. The results demonstrate that time-resolved autofluorescence can be potentially used as an important contrast mechanism to detect epithelial precancer.

  2. Dam methylation regulates the expression of SPI-5-encoded sopB gene in Salmonella enterica serovar Typhimurium.

    Science.gov (United States)

    Giacomodonato, Mónica N; Llana, Mariángeles Noto; Castañeda, María del Rosario Aya; Buzzola, Fernanda; García, Mauro D; Calderón, Marina Gallo; Sarnacki, Sebastián H; Cerquetti, María C

    2014-08-01

    DNA adenine methylation is an essential factor in Salmonella virulence. Here, we investigate the involvement of DNA adenine methylase (Dam) in the expression and translocation of a SPI-5-encoded effector of S. Typhimurium. SopB expression and secretion were determined using SopB-FLAG-tagged wild type and dam strains of S. Typhimurium. Western blot and quantitative reverse transcriptase PCR analysis showed that the dam mutant expresses lower levels of SopB protein and sopB mRNA than the wild type strain under SPI-1 and SPI-2 inducing conditions in vitro. SopB secretion was also considerably impaired in the absence of dam. In agreement with in vitro experiments, SopB synthesis in dam mutants recovered from infected epithelial cells and from murine mesenteric lymph nodes was reduced by 40% respect to the wild type strain (p SPI-5-encoded SopB effector.

  3. Bonded Excimer in Stacked Cytosines: A Semiclassical Simulation Study

    Directory of Open Access Journals (Sweden)

    Weifeng Wu

    2015-01-01

    Full Text Available The formation of a covalent bond between two stacked cytosines, one of which is excited by an ultrafast laser pulse, was studied by semiclassical dynamics simulations. The results show that a bonded excimer is created, which sharply lowers the energy gap between the LUMO and HOMO and consequently facilitates the deactivation of the electronically excited molecule. This is different from the case of two stacked adenines, where the formation of a covalent bond alters the nonadiabatic deactivation mechanism in two opposite ways. It lowers the energy gap and consequently leads to the coupling between the HOMO and LUMO levels, thus enhancing the deactivation of the electronically excited molecule. On the other hand, it leads to restriction of the deformation vibration of the pyrimidine in the excited molecule, because of a steric effect, and this delays the deactivation process of the excited adenine molecule with return to the electronic ground state.

  4. Influence of Formate on Bioactivity Material-thuringiensin Synthesized by Bacillus thuringiensis YBT-032

    Institute of Scientific and Technical Information of China (English)

    WANG Zhi; CHEN Xiong; CHEN Shouwen; SUN Ming; YU Ziniu

    2008-01-01

    The biological method to synthesize thuringiensin and the influence of formate on thuringiensin biosynthesis were investigated. Addition of 1.00 g/L formate to growth medium of bacillus thuringiensis YBT-032 resulted in significant enhancements in productions of citrate, a-ketoglutarate, intracellular adenine and thuringiensin. These results demonstrate that added formate attends metabolism of cell, facilitates carbon metabolic flux in tricarboxylic acid cycle and hexose monophosphate pathway. As a carbon source, formate facilitates cell growth, increases glucose consumption and enhances the ability of cell to synthesis adenine analogues, and subsequently thuringiensin. Thuringiensin production rate significantly enhanced from 6.44 to 8.46 mg·g-1·h-1 and transformation ratio from glucose to thuringiensin increased by 43.30%.

  5. Gold nanorods as photothermal agents and autofluorescence enhancer to track cell death during plasmonic photothermal therapy

    Science.gov (United States)

    Kannadorai, Ravi Kumar; Chiew, Geraldine Giap Ying; Luo, Kathy Qian; Liu, Quan

    2015-07-01

    The transverse and longitudinal plasmon resonance in gold nanorods can be exploited to localize the photothermal therapy and influence the fluorescence to monitor the treatment outcome at the same time. While the longitudinal plasmon peak contributes to the photothermal effect, the transverse peak can enhance fluorescence. After cells take in PEGylated nanorods through endocytosis, autofluorescence from endogenous fluorophores such as nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FAD) in the mitochondria is enhanced two times, which is a good indicator of the respiratory status of the cell. When cells are illuminated continuously with near infrared laser, the temperature reaches the hyperthermic region within the first four minutes, which demonstrates the efficiency of gold nanorods in photothermal therapy. The cell viability test and autofluorescence intensity show good correlation indicating the progress of cell death over time.

  6. One-pot microbial synthesis of 2'-deoxyribonucleoside from glucose, acetaldehyde, and a nucleobase.

    Science.gov (United States)

    Horinouchi, Nobuyuki; Ogawa, Jun; Kawano, Takako; Sakai, Takafumi; Saito, Kyota; Matsumoto, Seiichiro; Sasaki, Mie; Mikami, Yoichi; Shimizu, Sakayu

    2006-06-01

    A one-pot enzymatic synthesis of 2'-deoxyribonucleoside from glucose, acetaldehyde, and a nucleobase was established. Glycolysis by baker's yeast (Saccharomyces cerevisiae) generated ATP which was used to produce D: -glyceraldehyde 3-phosphate production from glucose via fructose 1,6-diphosphate. The D: -glyceraldehyde 3-phosphate produced was transformed to 2'-deoxyribonucleoside via 2-deoxyribose 5-phosphate and then 2-deoxyribose 1-phosphate in the presence of acetaldehyde and a nucleobase by deoxyriboaldolase, phosphopentomutase expressed in Escherichia coli, and a commercial nucleoside phosphorylase. About 33 mM 2'-deoxyinosine was produced from 600 mM glucose, 333 mM acetaldehyde and 100 mM adenine in 24 h. 2'-Deoxyinosine was produced from adenine due to the adenosine deaminase activity of E. coli transformants.

  7. Comparison of the Efficiency of Adeprophen and Antidepressants of Various Groups on the Model of Reserpine-Induced Depression in Rats.

    Science.gov (United States)

    Ozerov, A A; Bagmetova, V V; Chernysheva, Yu V; Tyurenkov, I N

    2016-03-01

    A new (aryloxyalkyl)adenine derivative Adeprophen (9-[2-(4-isopropylphenoxy)ethyl]adenine, VMA-99-82) has a strong antidepressant effect on the model of reserpine-induced depression in rats (single dose 4 mg/kg, intraperitoneally). This effect manifested in suppression of depression-like behavior in the Porsolt forced swimming test (shortening of immobility time and increase in immobility latency, number of jumping episodes, and time of active swimming) and sucrose consumption/preference test (increase in the consumption of 20% sucrose solution in g/100 g body weight and percentage of sucrose preference in relation to the total fluid preference). Adeprophen had a greater antidepressant effect than sertraline and fluoxetine, but was less potent than amitriptyline, imipramine, venlafaxine, and to a lesser extent to paroxetine. PMID:27021092

  8. Tight-binding parameters for charge transfer along DNA

    CERN Document Server

    Hawke, L G D; Simserides, C

    2009-01-01

    We systematically examine all the tight-binding parameters pertinent to charge transfer along DNA. The $\\pi$ molecular structure of the four DNA bases (adenine, thymine, cytosine, and guanine) is investigated by using the linear combination of atomic orbitals method with a recently introduced parametrization. The HOMO and LUMO wavefunctions and energies of DNA bases are discussed and then used for calculating the corresponding wavefunctions of the two B-DNA base-pairs (adenine-thymine and guanine-cytosine). The obtained HOMO and LUMO energies of the bases are in good agreement with available experimental values. Our results are then used for estimating the complete set of charge transfer parameters between neighboring bases and also between successive base-pairs, considering all possible combinations between them, for both electrons and holes. The calculated microscopic quantities can be used in mesoscopic theoretical models of electron or hole transfer along the DNA double helix, as they provide the necessar...

  9. Steady state and time-resolved autofluorescence studies of human colonic tissues

    Institute of Scientific and Technical Information of China (English)

    Buhong Li; Zhenxi Zhang; Shusen Xie

    2006-01-01

    Steady state and time-resolved autofluorescence spectroscopies are employed to study the autofluorescence characteristics of human colonic tissues in vitro. The excitation wavelength varies from 260 to 540 nm, and the corresponding fluorescence emission spectra are acquired from 280 to 800 nm. Significant difference in fluorescence intensity of excitation-emission matrices (EEMs) is observed between normal and tumor colonic tissues. Compared with normal colonic tissue, low nicotinamide adenine dinucleotide (phosphate) (NAD(P)H) and flavin adenine dinucleotide (FAD), and high amino acids and protoporphyrin Ⅸ (PpⅨ) fluorescences characterize high-grade malignant tissue. Moreover, the autofluorescence lifetimes of normal and carcinomatous colonic tissues at 635 nm under 397-nm excitation are about 4.32±0.12 and 18.45±0.05 ns, respectively. The high accumulation of endogenous PpⅨ in colonic cancers is demonstrated in both steady state and time-resolved autofluorescence spectroscopies.

  10. The Drosophila effector caspase Dcp-1 regulates mitochondrial dynamics and autophagic flux via SesB

    OpenAIRE

    DeVorkin, Lindsay; Go, Nancy Erro; Hou, Ying-Chen Claire; Moradian, Annie; Morin, Gregg B.; Gorski, Sharon M.

    2014-01-01

    Increasing evidence reveals that a subset of proteins participates in both the autophagy and apoptosis pathways, and this intersection is important in normal physiological contexts and in pathological settings. In this paper, we show that the Drosophila effector caspase, Drosophila caspase 1 (Dcp-1), localizes within mitochondria and regulates mitochondrial morphology and autophagic flux. Loss of Dcp-1 led to mitochondrial elongation, increased levels of the mitochondrial adenine nucleotide t...

  11. Structure-Function Analysis of Escherichia coli MnmG (GidA), a Highly Conserved tRNA-Modifying Enzyme

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Rong; Villarroya, Magda; Ruiz-Partida, Rafael; Li, Yunge; Proteau, Ariane; Prado, Silvia; Moukadiri, Ismaïl; Benítez-Páez, Alfonso; Lomas, Rodrigo; Wagner, John; Matte, Allan; Velázquez-Campoy, Adrián; Armengod, M.-Eugenia; Cygler, Miroslaw; (McGill); (Zaragoza); (LGM-Spain)

    2010-01-12

    The MnmE-MnmG complex is involved in tRNA modification. We have determined the crystal structure of Escherichia coli MnmG at 2.4-{angstrom} resolution, mutated highly conserved residues with putative roles in flavin adenine dinucleotide (FAD) or tRNA binding and MnmE interaction, and analyzed the effects of these mutations in vivo and in vitro. Limited trypsinolysis of MnmG suggests significant conformational changes upon FAD binding.

  12. Alcohol oxidase: A complex peroxisomal, oligomeric flavoprotein

    OpenAIRE

    Ozimek, Paulina; Veenhuis, Marten; van der Klei, Ida J.

    2005-01-01

    Alcohol oxidase (AO) is the key enzyme of methanol metabolism in methylotrophic yeast species. It catalyses the first step of methanol catabolism, namely its oxidation to formaldehyde with concomitant production of hydrogen peroxide. In its mature active form, AO is a molecule of high molecular mass (600 kDa) that consists of eight identical subunits, each of which carry one non-covalently bound flavin adenine nucleotide (FAD) molecule as the prosthetic group. In vivo, the protein is compartm...

  13. Feasibility analysis of an epidermal glucose sensor based on time-resolved fluorescence.

    OpenAIRE

    Katika, Kamal M; Pilon, Laurent

    2007-01-01

    The goal of this study is to test the feasibility of using an embedded time-resolved fluorescence sensor for monitoring glucose concentration. Skin is modeled as a multilayer medium with each layer having its own optical properties and fluorophore absorption coefficients, lifetimes, and quantum yields obtained from the literature. It is assumed that the two main fluorophores contributing to the fluorescence at these excitation and emission wavelengths are nicotinamide adenine dinucleotide (NA...

  14. Gaucher disease. III. Substrate specificity of glucocerebrosidase and the use of nonlabeled natural substrates for the investigation of patients.

    OpenAIRE

    Choy, F Y; Davidson, R G

    1980-01-01

    A reproducible and convenient method for assaying glucocerebrosidase activity using the natural substrates has been developed. From the insoluble pellet fraction of cultured skin fibroblast homogenates, released glucose was measured enzymically using hexokinase coupled with the glucose-6-phosphate dehydrogenase (G6PD) and nicotinamide adenine dinucleotide phosphate (NADP) system. Optimal enzyme assay conditions required both Triton X-100 and sodium taurocholate, pH 4.8. Glucocerebrosidase act...

  15. Hyperspectral in vivo two-photon microscopy of intrinsic contrast

    OpenAIRE

    Radosevich, Andrew J.; Bouchard, Matthew B.; Burgess, Sean A.; Chen, Brenda R.; Hillman, Elizabeth M. C.

    2008-01-01

    In vivo two-photon imaging of intrinsic contrast can provide valuable information about structural tissue elements such as collagen and elastin and fluorescent metabolites such as nicotinamide adenine dinucleotide. Yet low signal and overlapping emission spectra can make it difficult to identify and delineate these species in vivo. We present a novel approach that combines excitation scanning with spectrally resolved emission two-photon microscopy, allowing distinct structures to be delineate...

  16. SIRT1 confers protection against UVB- and H2O2-induced cell death via modulation of p53 and JNK in cultured skin keratinocytes

    OpenAIRE

    Cao, Cong; Lu, Shan; Kivlin, Rebecca; Wallin, Brittany; Card, Elizabeth; Bagdasarian, Andrew; Tamakloe, Tyrone; Wang, Wen-Jun; Song, Xiuzu; Chu, Wen-ming; Kouttab, Nicola; Xu, Aie; Wan, Yinsheng

    2008-01-01

    SIRT1 is a member of a highly conserved gene family (sirtuins) encoding nicotinamide adenine dinucleotide (NAD)+-dependent deacetylases, originally found to deacetylate histones leading to increased DNA stability and prolonged survival in yeast and higher organisms, including mammals. SIRT1 has been found to function as a deacetylase for numerous protein targets involved in various cellular pathways, including stress responses, apoptosis and axonal degeneration. However, the role of SIRT1 in ...

  17. Large-Scale Deletion and Point Mutations of the Nuclear NDUFV1 and NDUFS1 Genes in Mitochondrial Complex I Deficiency

    OpenAIRE

    Bénit, Paule; Chretien, Dominique; Kadhom, Nohman; de Lonlay-Debeney, Pascale; Cormier-Daire, Valérie; Cabral, Aguinaldo; Peudenier, Sylviane; Rustin, Pierre; Munnich, Arnold; Rötig, Agnès

    2001-01-01

    Reduced nicotinamide adenine dinucleotide (NADH):ubiquinone oxidoreductase (complex I) is the largest complex of the mitochondrial respiratory chain and complex I deficiency accounts for ∼30% cases of respiratory-chain deficiency in humans. Only seven mitochondrial DNA genes, but >35 nuclear genes encode complex I subunits. In an attempt to elucidate the molecular bases of complex I deficiency, we studied the six most-conserved complex I nuclear genes (NDUFV1, NDUFS8, NDUFS7, NDUFS1, NDUFA8, ...

  18. Age-Associated Changes In Oxidative Stress and NAD+ Metabolism In Human Tissue

    OpenAIRE

    Hassina Massudi; Ross Grant; Nady Braidy; Jade Guest; Bruce Farnsworth; Guillemin, Gilles J

    2012-01-01

    Nicotinamide adenine dinucleotide (NAD(+)) is an essential electron transporter in mitochondrial respiration and oxidative phosphorylation. In genomic DNA, NAD(+) also represents the sole substrate for the nuclear repair enzyme, poly(ADP-ribose) polymerase (PARP) and the sirtuin family of NAD-dependent histone deacetylases. Age associated increases in oxidative nuclear damage have been associated with PARP-mediated NAD(+) depletion and loss of SIRT1 activity in rodents. In this study, we furt...

  19. CCN2: a mechanosignaling sensor modulating integrin-dependent connective tissue remodeling in fibroblasts?

    OpenAIRE

    Leask, Andrew

    2013-01-01

    Tensegrity (tensional integrity) is an emerging concept governing the structure of the body. Integrin-mediated mechanical tension is essential for connective tissue function in vivo. For example, in adult skin fibroblasts, the integrin β1 subunit mediates adhesion to collagen and fibronectin. Moreover, integrin β1, through its abilities to activate latent TGFβ1 and promote collagen production through focal adhesion kinase/rac1/nicotinamide adenine dinucleotide phosphate oxidase (NOX)/reactive...

  20. In Vivo Multiphoton NADH Fluorescence Reveals Depth-Dependent Keratinocyte Metabolism in Human Skin

    OpenAIRE

    Balu, Mihaela; Mazhar, Amaan; Hayakawa, Carole K.; Mittal, Richa; Krasieva, Tatiana B.; Konig, Karsten; Venugopalan, Vasan; Tromberg, Bruce J.

    2013-01-01

    We employ a clinical multiphoton microscope to monitor in vivo and noninvasively the changes in reduced nicotinamide adenine dinucleotide (NADH) fluorescence of human epidermal cells during arterial occlusion. We correlate these results with measurements of tissue oxy- and deoxyhemoglobin concentration during oxygen deprivation using spatial frequency domain imaging. During arterial occlusion, a decrease in oxyhemoglobin corresponds to an increase in NADH fluorescence in the basal epidermal c...

  1. Identification of a Novel Mutation in the CYBB Gene, p.Asp378Gly, in a Patient With X-linked Chronic Granulomatous Disease

    OpenAIRE

    Song, Sang-Mi; Park, Mi-Ran; Kim, Do-Soo; Kim, Jihyun; Kim, Yae-Jean; Ki, Chang-Seok; Ahn, Kangmo

    2014-01-01

    Chronic granulomatous disease (CGD) is a rare immunodeficiency disease, which is characterized by the lack of a functional nicotinamide adenine dinucleotide phosphate (NADPH) oxidase in phagocytes. The disease presents leukocytosis, anemia, hypergammaglobulinemia, and granuloma formation of the skin, lung, or lymph nodes. The mutation of the CYBB gene encoding gp91phox, located on chromosome Xp21.1 is one of the causes of CGD. We report a patient with X-linked CGD who carried a novel mutation...

  2. Solasodine accumulation in regenerated plants of Solanum torvum Sw Acúmulo de solasodina em plantas micropropagadas de Solanum torvum Sw

    OpenAIRE

    C. B. Moreira; Lima, S.S. de; M.A Esquibel; A. Sato

    2010-01-01

    A nodal segment culture was developed in order to assess Solanum torvum Sw. regeneration and solasodine levels. The influence of auxins (indoleacetic acid, 1-Naphthaleneacetic acid) and benzyl adenine on S. torvum growth in micropropagation was investigated. A nodal segment culture was initiated with seeds germinated in MS basal medium added of GA3 and grown in different concentrations of IAA, IAA + BAP and NAA + BAP. Sixty-day-old plants from the in vitro culture were collected, frozen and l...

  3. Decreased expression of plastidial adenylate kinase in potato tubers results in an enhanced rate of respiration and a stimulation of starch synthesis that is attributable to post-translational redox-activation of ADP-glucose pyrophosphorylase

    OpenAIRE

    Oliver, S; Tiessen, A.; Fernie, A.; P. Geigenberger

    2008-01-01

    Adenine nucleotides are of general importance for many aspects of cell function, but their role in the regulation of biosynthetic processes is still unclear. It was previously reported that decreased expression of plastidial adenylate kinase, catalysing the interconversion of ATP and AMP to ADP, leads to increased adenylate pools and starch content in transgenic potato tubers. However, the underlying mechanisms were not elucidated. Here, it is shown that decreased expression of plastidial ade...

  4. Absolute total and partial cross sections for ionization of nucleobases by proton impact in the Bragg peak velocity range

    OpenAIRE

    Tabet, J.; Eden, S.; Feil, S.; Abdoul-Carime, H.; Farizon, B.; Farizon, M.; Ouaskit, S.; Märk, T.D.

    2010-01-01

    We present experimental results for 80 keV proton impact ionization of nucleobases (adenine, cytosine, thymine and uracil) based on an event by event analysis of the different ions produced combined with an absolute target density determination. We are able to disentangle in detail the various proton ionization channels from mass analyzed product ion signals in coincidence with the charge-analyzed projectile. Thus, for the first time, cross sections and fragmentation patterns are compared for...

  5. Effects of perinatal protein deprivation and recovery on esophageal myenteric plexus

    Institute of Scientific and Technical Information of China (English)

    Flavio; M; Greggio; Ricardo; BV; Fontes; Laura; B; Maifrino; Patricia; Castelucci; Romeu; Rodrigues; de; Souza; Edson; A; Liberti

    2010-01-01

    AIM:To evaluate effects of preand postnatal protein deprivation and postnatal recovery on the myenteric plexus of the rat esophagus. METHODS: Three groups of young Wistar rats (aged 42 d) were studied: normalfed (N42), proteindeprived (D42), and proteinrecovered (R42). The myenteric neurons of their esophagi were evaluated by histochemical reactions for nicotinamide adenine dinucleotide (NADH), nitrergic neurons (NADPH)diaphorase and acetylcholinesterase (AChE), immunohistochemical reaction for vasoactive i...

  6. Steroid Biomarkers and Genetic Studies Reveal Inactivating Mutations in Hexose-6-Phosphate Dehydrogenase in Patients with Cortisone Reductase Deficiency

    OpenAIRE

    Lavery, Gareth G.; Walker, Elizabeth A.; Tiganescu, Ana; Ride, Jon P.; Shackleton, Cedric H. L.; Tomlinson, Jeremy W.; Connell, John M C; Ray, David W; Biason-Lauber, Anna; Malunowicz, Ewa M.; Arlt, Wiebke; Stewart, Paul M.

    2008-01-01

    Context: Cortisone reductase deficiency (CRD) is characterized by a failure to regenerate cortisol from cortisone via 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), resulting in increased cortisol clearance, activation of the hypothalamic-pituitary-axis (HPA) and ACTH-mediated adrenal androgen excess. 11β-HSD1 oxoreductase activity requires the reduced nicotinamide adenine dinucleotide phosphate-generating enzyme hexose-6-phosphate dehydrogenase (H6PDH) within the endoplasmic reticulum. ...

  7. A Highly Stable d-Amino Acid Oxidase of the Thermophilic Bacterium Rubrobacter xylanophilus

    OpenAIRE

    Takahashi, Shouji; Furukawara, Makoto; Omae, Keishi; Tadokoro, Namiho; Saito, Yayoi; Abe, Katsumasa; Kera, Yoshio

    2014-01-01

    d-Amino acid oxidase (DAO) is a biotechnologically attractive enzyme that can be used in a variety of applications, but its utility is limited by its relatively poor stability. A search of a bacterial genome database revealed a gene encoding a protein homologous to DAO in the thermophilic bacterium Rubrobacter xylanophilus (RxDAO). The recombinant protein expressed in Escherichia coli was a monomeric protein containing noncovalently bound flavin adenine dinucleotide as a cofactor. This protei...

  8. A click chemistry approach to pleuromutilin derivatives. Part 3

    DEFF Research Database (Denmark)

    Dreier, Ida; Hansen, Lykke H; Nielsen, Poul;

    2014-01-01

    Five promising pleuromutilin derivatives from our former studies, all containing adenine on various linkers, were supplemented with two new compounds. The binding to Escherichia coli ribosomes was verified by extensive chemical footprinting analysis. The ability to inhibit bacterial growth was in...... investigated on two Staphylococcus aureus strains and compared to the pleuromutilin drugs tiamulin and valnemulin. Three of the compounds show an effect similar to tiamulin and one compound shows an excellent effect similar to valnemulin....

  9. Fourier transform infrared spectroscopic studies of proton transfer processes and the dissociation of Zn2+-bound water in alcohol dehydrogenases.

    Science.gov (United States)

    Nadolny, C; Zundel, G

    1997-08-01

    The following complexes were investigated by Fourier transform difference spectroscopy: binary complexes of alcohol dehydrogenases from yeast (YADH) and horse liver (LADH) with nicotinamide adenine dinucleotide (NAD+) and adenosine (5')-diphospho(5)-beta-D-ribose (ADP-Rib); the binary complex of Zn2+-free YADH with NAD+, the ternary complex of LADH with NAD+ and 2,2,2-trifluoroethanol. After addition of NAD+ to YADH and LADH, protonation of the N1 atom of the adenine ring of NAD+ is observed. It is shown that this proton arises from the dissociation of the Zn2+-bound water. The interaction of the Zn2+ ion with water is very strong, since this interaction is not just an electrostatic interaction. If the Zn2+ ions are in a tetrahedral environment, a large covalent contribution also occurs. If ADP-Rib is present instead of NAD+, no protonation of the N1 atom of the adenine ring of ADP-Rib is found, which demonstrates that the positively charged nicotinamide ring favors the conduction of the positive charge. All these results confirm the mechanism of Brändén et al. (1975): the Zn2+-bound water is split and the arising (OH)- deprotonates the alcohol. In the case of the ternary complex of LADH with NAD+ and 2,2,2-trifluoroethanol, we demonstrate that the alcohol is deprotonated and the alcoholate ion is bound directly to the Zn2+ ion. The conduction of the proton from the active site to the N1 atom of adenine occurs via a hydrogen-bonded chain with large proton polarizability due to collective proton motion. The nature and mechanism of this pathway are discussed on the basis of data from previous studies.

  10. Age-Associated Changes In Oxidative Stress and NAD+ Metabolism In Human Tissue

    OpenAIRE

    Massudi, Hassina; Grant, Ross; Braidy, Nady; Guest, Jade; Farnsworth, Bruce; Guillemin, Gilles J.

    2012-01-01

    Nicotinamide adenine dinucleotide (NAD+) is an essential electron transporter in mitochondrial respiration and oxidative phosphorylation. In genomic DNA, NAD+ also represents the sole substrate for the nuclear repair enzyme, poly(ADP-ribose) polymerase (PARP) and the sirtuin family of NAD-dependent histone deacetylases. Age associated increases in oxidative nuclear damage have been associated with PARP-mediated NAD+ depletion and loss of SIRT1 activity in rodents. In this study, we further in...

  11. IN VITRO CLONAL PROPAGATION OF A PROMISING AGROFUEL PRODUCING-PLANT : JATROPHA CURCAS L.

    OpenAIRE

    Medza Mve, Samson Daudet; Mergeai, Guy; Baudoin, Jean-Pierre; TOUSSAINT, André

    2009-01-01

    In the present investigation, in vitro clonal propagation of two-month-old Jatropha curcas L. was achieved employing nodal explants. Axillary shoot bud proliferation was best initiated on Murashige and Skoog’s (MS) basal medium supplemented with N6-benzyladenine (BA) and adenine sulphate. This medium allowed the production of 3.1 ± 0.5 shoots per nodal explant with 3.5 ± 0.8 cm average length after 3-4 weeks.

  12. Polyol metabolism by Rhizobium trifolii.

    OpenAIRE

    Primrose, S. B.; Ronson, C W

    1980-01-01

    In Rhizobium trifolii 7000, the polyols myo-inositol, xylitol, ribitol, D-arabitol, D-mannitol, D-sorbital, and dulcitol are metabolized by inducible nicotinamide adenine dinucleotide-dependent polyol dehydrogenases. Five different polyol dehydrogenases were recognized: inositol dehydrogenase, specific for inositil; ribitol dehydrogenase, specific for ribitol; D-arabitol dehydrogenase, which oxidized D-arabitol, D-mannitol, and D-sorbitol; xylitol dehydrogenase, which oxidized xylitol and D-s...

  13. Anticancer Agents Targeted to Sirtuins

    OpenAIRE

    Tomohiro Kozako; Takayoshi Suzuki; Makoto Yoshimitsu; Naomichi Arima; Shin-ichiro Honda; Shinji Soeda

    2014-01-01

    Sirtuins are nicotinamide adenine dinucleotide+-dependent deacetylases of which there are seven isoforms (SIRT1–7). Sirtuin activity is linked to gene expression, lifespan extension, neurodegeneration, and age-related disorders. Numerous studies have suggested that sirtuins could be of great significance with regard to both antiaging and tumorigenesis, depending on its targets in specific signaling pathways or in specific cancers. Recent studies have identified small chemical compounds that m...

  14. Role of NADPH Oxidases in Liver Fibrosis

    OpenAIRE

    Paik, Yong-Han; Kim, Jonghwa; Aoyama, Tomonori; De Minicis, Samuele; Bataller, Ramon; Brenner, David A

    2014-01-01

    Significance: Hepatic fibrosis is the common pathophysiologic process resulting from chronic liver injury, characterized by the accumulation of an excessive extracellular matrix. Multiple lines of evidence indicate that oxidative stress plays a pivotal role in the pathogenesis of liver fibrosis. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) is a multicomponent enzyme complex that generates reactive oxygen species (ROS) in response to a wide range of stimuli. In addition to...

  15. A source for microhydrated biomolecules

    Energy Technology Data Exchange (ETDEWEB)

    Förstel, M.; Hergenhahn, U., E-mail: uwe.hergenhahn@ipp.mpg.de [Max-Planck-Institut für Plasmaphysik, Wendelsteinstraße 1, 17491 Greifswald (Germany); Neustetter, M.; Denifl, S. [Institut für Ionenphysik und Angewandte Physik, Technikerstraße 25, 6020 Innsbruck (Austria); Lelievre, F. [Max-Planck-Institut für Plasmaphysik, Wendelsteinstraße 1, 17491 Greifswald (Germany); University Paris-Sud 11, Faculté des Science d’Orsay, 91405 Orsay (France)

    2015-07-15

    We describe the construction of an apparatus for the production of a molecular jet of microhydrated biomolecules. Our design uses a water reservoir producing water vapour, which then passes through a separate reservoir containing a vapour of a sublimated biomolecule. The mixture coexpands into a molecular beam apparatus through a conical nozzle. Mass spectra showing water-adenin and water-uracil complexes are shown as typical examples. Suitable expansion conditions are reached without the use of an inert carrier gas.

  16. Untersuchungen zur Wirkung von Saponinen als Verstärker der Penetration von Proteinen im Zellmodell

    OpenAIRE

    Weng, Alexander

    2010-01-01

    Triterpenoid saponins from Gypsophila paniculata L. are known to enhance the cytotoxicity of type I ribosome-inactivating proteins (type I RIP). These proteins exhibit N-glycosidase activity and remove an essential adenine residue from the ribosomal RNA. Up to now it was assumed that the saponin-mediated toxicity enhancement of these toxins is due to a an increased endocytosis or phagocytosis in saponin treated cells. To scruntinize this hypothesis, appropriate in vitro models were estab...

  17. Neuronal and extraneuronal release of ATP and NAD+ in smooth muscle

    OpenAIRE

    Mutafova-Yambolieva, Violeta N.

    2012-01-01

    Adenosine 5′-triphosphate (ATP) and nicotinamide adenine dinucleotide (NAD+) are key intracellular constituents involved in energy transfer and redox homeostasis in the cell. ATP is also released in the extracellular space and in the past half century it has been assumed to be the purinergic neurotransmitter in many systems including smooth muscle. In some smooth muscles (i.e., the human urinary bladder detrusor muscle) ATP does appear to be primarily released from nerves upon action potentia...

  18. Histone Deacetylase Enzymes as Potential Drug Targets in Cancer and Parasitic Diseases

    OpenAIRE

    Mehdi Ouaissi; Ali Ouaissi

    2006-01-01

    The elucidation of the mechanisms of transcriptional activation and repression in eukaryotic cells has shed light on the important role of acetylation-deacetylation of histones mediated by histone acetyltransferases (HATs) and histone deacetylases (HDACs), respectively. Another group belonging to the large family of sirtuins (silent information regulators (SIRs)) has an (nicotinamide adenine dinucleotide) NAD+-dependent HDAC activity. Several inhibitors of HDACs (HDIs) have been shown to exer...

  19. Environ: E00191 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available E00191 Artemisia leaf (JP16) Artemisiae folium Gaiyo Crude drug Cineole [CPD:C09844...C05785], Adenine [CPD:C00147], Acetylcholine [CPD:C01996], Choline [CPD:C00114], beta-Thujone Arte...misia princeps [TAX:223870], Artemisia montana, Artemisia argyi [TAX:259893], Artemisia [TA...X:4219] Same as: D06894 Asteraceae (daisy family) Artemisia leaf (dried); Standards for non-pharmacopoeial crude drugs ...

  20. Characterization of H2O-forming NADH oxidase from Streptococcus pyogenes and its application in l-rare sugar production

    DEFF Research Database (Denmark)

    Gao, Hui; Tiwari, Manish Kumar; Kang, Yun Chan;

    2012-01-01

    A nicotinamide adenine dinucleotide (NADH) oxidase from Streptococcus pyogenes MGAS10394 (SpNox) was cloned and overexpressed in Escherichia coli BL21 (DE3). The purified SpNox enzyme had optimal pH and temperature of 7.0 and 55°C, respectively, with a K(m) of 27.0μM and a k(cat)/K(m) of 1.1×10(7)s...

  1. Quantification of carnosine- related peptides by microchip electrophoresis with chemiluminescence detection

    OpenAIRE

    Zhao, Shulin; Huang, Yong; Shi, Ming; Huang, Junming; Liu, Yi-Ming

    2009-01-01

    A microchip electrophoresis (MCE) method with chemiluminescence (CL) detection was developed for the determination of carnosine-related peptides including carnosine, homocarnosine and anserine in biological samples. A simple integrated MCE-CL system was built to perform the assays. The highly sensitive CL detection was achieved by means of the CL reaction between hydrogen peroxide and N-(4-aminobutyl)- N-ethylisoluminol-tagged peptides in the presence of adenine as a CL enhancer and Co2+ as a...

  2. Aldo-keto reductase (AKR) superfamily: Genomics and annotation

    OpenAIRE

    Mindnich Rebekka D; Penning Trevor M

    2009-01-01

    Abstract Aldo-keto reductases (AKRs) are phase I metabolising enzymes that catalyse the reduced nicotinamide adenine dinucleotide (phosphate) (NAD(P)H)-dependent reduction of carbonyl groups to yield primary and secondary alcohols on a wide range of substrates, including aliphatic and aromatic aldehydes and ketones, ketoprostaglan-dins, ketosteroids and xenobiotics. In so doing they functionalise the carbonyl group for conjugation (phase II enzyme reactions). Although functionally diverse, AK...

  3. Role of Nicotinamide in DNA Damage, Mutagenesis, and DNA Repair

    OpenAIRE

    Devita Surjana; Halliday, Gary M.; Damian, Diona L.

    2010-01-01

    Nicotinamide is a water-soluble amide form of niacin (nicotinic acid or vitamin B3). Both niacin and nicotinamide are widely available in plant and animal foods, and niacin can also be endogenously synthesized in the liver from dietary tryptophan. Nicotinamide is also commercially available in vitamin supplements and in a range of cosmetic, hair, and skin preparations. Nicotinamide is the primary precursor of nicotinamide adenine dinucleotide (NAD+), an essential coenzyme in ATP production a...

  4. Tristetraprolin inhibits gastric cancer progression through suppression of IL-33

    OpenAIRE

    Kaiyuan Deng; Hao Wang; Ting Shan; Yigang Chen; Hong Zhou; Qin Zhao; Jiazeng Xia

    2016-01-01

    Tristetraprolin (TTP) is an adenine/uridine (AU)-rich element (ARE)-binding protein that can induce degradation of mRNAs. In this study, we report that TTP suppresses the expression of interleukin-33 (IL-33), a tumor-promoting inflammatory cytokine, and thereby inhibits the progression of gastric cancer (GC). Overexpression of TTP decreased the level of IL-33, whereas knockdown of TTP increased IL-33 levels. We also discovered that TTP inhibited the proliferation, migration, and invasion of G...

  5. Dataset of the AAC2 conformations in the c-, intermediate- and m-states obtained from free-energy simulations

    OpenAIRE

    Pietropaolo, Adriana; Pierri, Ciro Leonardo; Palmieri, Ferdinando; Klingenberg, Martin

    2016-01-01

    The data reported herein are related to the article entitled: “The switching mechanism of the mitochondrial ADP/ATP carrier explored by free-energy landscapes” (Pietropaolo et al., 2016) [1]. We report the coordinates of the ADP/ATP carrier (AAC2) in the presence and absence of adenine and guanine nucleotides in the c-, intermediate- and m-states obtained from the free-energy simulations and corresponding to the free-energy minima.

  6. Differential modulation of ATP-induced calcium signalling by A1 and A2 adenosine receptors in cultured cortical astrocytes

    OpenAIRE

    Alloisio, Susanna; Cugnoli, Carlo; Ferroni, Stefano; Nobile, Mario

    2004-01-01

    Despite the accumulating evidence that under various pathological conditions the extracellular elevation of adenine-based nucleotides and nucleosides plays a key role in the control of astroglial reactivity, how these signalling molecules interact in the regulation of astrocyte function is still largely elusive.The action of the nucleoside adenosine in the modulation of the intracellular calcium signalling ([Ca2+]i) elicited by adenosine 5′-triphosphate (ATP)-induced activation of P2 purinoce...

  7. NAD+ protects against EAE by regulating CD4+ T-cell differentiation

    OpenAIRE

    Tullius, Estefan G.; Biefer, Hector Rodriguez Cetina; Li, Suyan; Trachtenberg, Alexander J.; Edtinger, Karoline; Quante, Markus; Krenzien, Felix; Uehara, Hirofumi; Yang, Xiaoyong; Kissick, Haydn T.; Kuo, Winston P.; Ghiran, Ionita; Fuente García, Miguel Ángel de la; Arredouani, Mohamed S.; Camacho, Virginia

    2014-01-01

    Producción Científica CD4(+) T cells are involved in the development of autoimmunity, including multiple sclerosis (MS). Here we show that nicotinamide adenine dinucleotide (NAD(+)) blocks experimental autoimmune encephalomyelitis (EAE), a mouse model of MS, by inducing immune homeostasis through CD4(+)IFNγ(+)IL-10(+) T cells and reverses disease progression by restoring tissue integrity via remyelination and neuroregeneration. We show that NAD(+) regulates CD4(+) T-cell differentiation th...

  8. Elimination Voltammetry with Linear Scan as a New Detection Method for DNA Sensors

    OpenAIRE

    Rene Kizek*; David Potesil; Vojtech Adam; Jitka Petrlova; Frantisek Jelen; Libuse Trnkova

    2005-01-01

    The paper describes successful coupling of adsorptive transfer stripping (AdTS) and elimination voltammetry with linear scan (EVLS) for the resolution of reduction signals of cytosine (C) and adenine (A) residues in hetero-oligodeoxynucleotides (ODNs). Short ODNs (9-mers and 20-mers) were adsorbed from a small volume on a hanging mercury drop electrode (HMDE). After washing of the ODN-modified electrode by water and its transferring to an electrochemical cell, voltammetric curves were measure...

  9. CRISPRscan: designing highly efficient sgRNAs for CRISPR/Cas9 targeting in vivo

    OpenAIRE

    Moreno-Mateos, Miguel A.; Vejnar, Charles E.; Beaudoin, Jean-Denis; Fernandez, Juan P.; Mis, Emily K.; Khokha, Mustafa K.; Giraldez, Antonio J.

    2015-01-01

    CRISPR/Cas9 technology provides a powerful system for genome engineering. However, variable activity across different single guide RNAs (sgRNAs) remains a significant limitation. We have analyzed the molecular features that influence sgRNA stability, activity and loading into Cas9 in vivo. We observe that guanine enrichment and adenine depletion increase sgRNA stability and activity, while loading, nucleosome positioning and Cas9 off-target binding are not major determinants. We additionally ...

  10. Etude du rôle des cytokinines végétales et fongiques dans l'interaction riz-Magnaporthe oryzae

    OpenAIRE

    Chanclud, Emilie

    2015-01-01

    The blast disease caused by Magnaporthe oryzae is one of the most devastating diseases on rice leading to important yield loss. Plant hormones, like salicylic acid, play a central role in plant resistance establishment. Among these hormones, cytokinins (CKs) are adenine derivatives well described to modulate root/shoot growth and differentiation, cell viability and nutrient distribution. Previous studies have shown that these hormonal compounds can also affect plant host resistance in differe...

  11. The Photochemistry of Pyrimidine in Pure H2O Ice Subjected to Different Radiation Environments and the Formation of Uracil

    Science.gov (United States)

    Nuevo, M.; Chen, Y.-J.; Materese. C. K..; Hu, W.-J.; Qiu, J.-M.; Wu, S.-R.; Fung, H.-S.; Sandford, S. A.; Chu, C.-C.; Yih, T.-S.; Wu, R.; Ip, W.-H.

    2013-01-01

    Nucleobases are N-heterocycles which are the informational subunits of DNA and RNA. They include pyrimidine bases (uracil, cytosine, and thymine) and purine bases (adenine and guanine). Nucleobases have been detected in several meteorites, although no Nheterocycles have been observed in space to data. Laboratory experiments showed that the ultraviolet (UV) irradiation of pyrimidine in pure H2O ice at low temperature (function of the photon energy.

  12. X-ray diffraction

    International Nuclear Information System (INIS)

    We have been interested in structural elucidation by x-ray diffraction of compounds of biological interest. Understanding exactly how atoms are arranged in three-dimensional arrays as molecules can help explain the relationship between structure and functions. The species investigated may vary in size and shape; our recent studies included such diverse substances as antischistosomal drugs, a complex of cadmium with nucleic acid base, nitrate salts of adenine, and proteins

  13. NADPH Oxidases in Heart Failure: Poachers or Gamekeepers?

    OpenAIRE

    Zhang, Min; Perino, Alessia; Ghigo, Alessandra; Hirsch, Emilio; Shah, Ajay M.

    2013-01-01

    Significance: Oxidative stress is involved in the pathogenesis of heart failure but clinical antioxidant trials have been unsuccessful. This may be because effects of reactive oxygen species (ROS) depend upon their source, location, and concentration. Nicotinamide adenine dinucleotide phosphate oxidase (Nox) proteins generate ROS in a highly regulated fashion and modulate several components of the heart failure phenotype. Recent Advances: Two Nox isoforms, Nox2 and Nox4, are expressed in the ...

  14. NADPH Oxidases in Vascular Pathology

    OpenAIRE

    Konior, Anna; Schramm, Agata; Czesnikiewicz-Guzik, Marta; Tomasz J. Guzik

    2014-01-01

    Significance: Reactive oxygen species (ROS) play a critical role in vascular disease. While there are many possible sources of ROS, nicotinamide adenine dinucleotide phosphate (NADPH) oxidases play a central role. They are a source of “kindling radicals,” which affect other enzymes, such as nitric oxide synthase endothelial nitric oxide synthase or xanthine oxidase. This is important, as risk factors for atherosclerosis (hypertension, diabetes, hypercholesterolemia, and smoking) regulate the ...

  15. NADPH oxidase expression and production of superoxide by human corneal stromal cells

    OpenAIRE

    O’Brien, William J.; Heimann, Tom; Rizvi, Farhan

    2009-01-01

    Purpose Superoxide (O2 .-) may function as a second messenger or regulator of signal transduction when produced at low concentrations in the proper locations within cells. The purpose of these studies was to determine whether human corneal stromal (HCS) fibroblasts are capable of producing O2 .- via nicotinamide adenine dinucleotide phosphate (NADPH) oxidases, a family of protein complexes believed to be responsible for the localized and limited production of O2 .- with regulatory activity. M...

  16. Single sample extraction protocol for the quantification of NAD and NADH redox states in Saccharomyces cerevisiae

    OpenAIRE

    Sporty, Jennifer L.; Kabir, Md. Mohiuddin; Turteltaub, Kenneth W.; Ognibene, Ted; Lin, Su-Ju; Bench, Graham

    2008-01-01

    A robust redox extraction protocol for quantitative and reproducible metabolite isolation and recovery has been developed for simultaneous measurement of nicotin-amide adenine dinucleotide (NAD) and its reduced form, NADH, from Saccharomyces cerevisiae. Following culture in liquid media, yeast cells were harvested by centrifugation and then lysed under nonoxidizing conditions by bead blasting in ice-cold, nitrogen-saturated 50 mM ammonium acetate. To enable protein denaturation, ice cold nitr...

  17. Methotrexate inhibits neutrophil function by stimulating adenosine release from connective tissue cells.

    OpenAIRE

    Cronstein, B. N.; Eberle, M A; Gruber, H E; Levin, R I

    1991-01-01

    Although commonly used to control a variety of inflammatory diseases, the mechanism of action of a low dose of methotrexate remains a mystery. Methotrexate accumulates intracellularly where it may interfere with purine metabolism. Therefore, we determined whether a 48-hr pretreatment with methotrexate affected adenosine release from [14C]adenine-labeled human fibroblasts and umbilical vein endothelial cells. Methotrexate significantly increased adenosine release by fibroblasts from 4 +/- 1% t...

  18. Sirt1 in cerebral ischemia

    OpenAIRE

    Koronowski, Kevin B.; Perez-Pinzon, Miguel A.

    2015-01-01

    Cerebral ischemia is among the leading causes of death worldwide. It is characterized by a lack of blood flow to the brain that results in cell death and damage, ultimately causing motor, sensory, and cognitive impairments. Today, clinical treatment of cerebral ischemia, mostly stroke and cardiac arrest, is limited and new neuroprotective therapies are desperately needed. The Sirtuin family of oxidized nicotinamide adenine dinucleotide (NAD+)-dependent deacylases has been shown to govern seve...

  19. A mixture of amino acids and other small molecules present in the serum suppresses the growth of murine and human tumors in vivo

    OpenAIRE

    Kulcsár, Gyula; Gaál, Dezső; Kulcsár, Péter I.; Schulcz, Ákos; Czömpöly, Tamás

    2012-01-01

    Previously we have hypothesized that the small molecules which are selectively accumulated in cancer cells might participate in a non-immunological antitumor surveillance mechanism. We demonstrated earlier that a mixture of experimentally selected substances (“active mixture”, AM: l-arginine, l-histidine, l-methionine, l-phenylalanine, l-tyrosine, l-tryptophan, l-ascorbate, d-biotin, pyridoxine, riboflavin, adenine, l(-)malate) possesses a selective toxic effect in vitro on a variety of tumor...

  20. SIRT1 protects against myocardial ischemia–reperfusion injury via activating eNOS in diabetic rats

    OpenAIRE

    Ding, Mingge; Lei, Jingyi; Han, Hongcheng; Li, Weibo; Qu, Yinxian; Fu, Enqing; Fu, Feng; Wang, Xiaoming

    2015-01-01

    Background Diabetic patients are more sensitive to myocardial ischemic injury than non-diabetic patients. Silent information regulator 1 (SIRT1) is a nicotinamide adenine dinucleotide-dependent histone deacetylase making the heart more resistant to ischemic injury. As SIRT1 expression is considered to be reduced in diabetic heart, we therefore hypothesized that up-regulation of SIRT1 in the diabetic heart may overcome its increased susceptibility to ischemic injury. Methods Male Sprague–Dawle...

  1. Effects of hyperglycemia on sperm and testicular cells of Goto-Kakizaki and streptozotocin-treated rat models for diabetes

    OpenAIRE

    Amaral, Sandra; Moreno, António J.; Santos, Maria Sancha; Seiça, Raquel; Ramalho-Santos, João

    2006-01-01

    Diabetes mellitus is a degenerative disease that has deleterious effects on male reproductive function, possibly through an increase in oxidative stress. This study was conducted in order to clarify the mechanisms by which oxidative stress influences animal models for both type 1 (streptozotocin-treated rats, STZ) and type 2 (Goto-Kakizaki (GK) rats) diabetes. We determined the extent of lipid peroxidation, protein oxidation, lactate levels, adenine nucleotides, adenylate energy charge and th...

  2. Principia of cancer therapy, 2

    International Nuclear Information System (INIS)

    When given concomitantly with the regimen for rescue of radiation dermatitis consisting of urokinase, glutathione, vitamin C, flavin adenine dinucleotide and cytochrome c, the peroral administration of zinc was seen to be beneficial in the treatment of radiation-related, undermining ulcers, either a neurogenic and decubital ulcer complicating the radiotherapy or radiation skin cancer with painful ulcers. The zinc element may thus be essential in various processes of wound healing and repair of the DNA damage as related to the radiotherapy. (author)

  3. Characterization of CetA and CetB, a bipartite energy taxis system in Campylobacter jejuni

    OpenAIRE

    Elliott, Kathryn T; DiRita, Victor J.

    2008-01-01

    The energy taxis receptor Aer, in Escherichia coli, senses changes in the redox state of the electron transport system via an flavin adenine dinucleotide cofactor bound to a PAS domain. The PAS domain (a sensory domain named after three proteins Per, ARNT and Sim, where it was first identified) is thought to interact directly with the Aer HAMP domain to transmit this signal to the highly conserved domain (HCD) found in chemotaxis receptors. An apparent energy taxis system in Campylobacter jej...

  4. Differential adsorption of nucleic acid bases: Relevance to the origin of life

    OpenAIRE

    Sowerby, Stephen J.; Cohn, Corey A; Heckl, Wolfgang M.; Holm, Nils G

    2001-01-01

    The adsorption of organic molecules onto the surfaces of inorganic solids has long been considered a process relevant to the origin of life. We have determined the equilibrium adsorption isotherms for the nucleic acid purine and pyrimidine bases dissolved in water on the surface of crystalline graphite. The markedly different adsorption behavior of the bases describes an elutropic series: guanine > adenine > hypoxanthine > thymine > cytosine > uracil. We propose th...

  5. Fabrication of submicron proteinaceous structures by direct laser writing

    Energy Technology Data Exchange (ETDEWEB)

    Serien, Daniela [Center for International Research on Integrative Biomedical Systems, Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, 153-8505 Tokyo (Japan); Takeuchi, Shoji, E-mail: takeuchi@iis.u-tokyo.ac.jp [Center for International Research on Integrative Biomedical Systems, Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, 153-8505 Tokyo (Japan); ERATO Takeuchi Biohybrid Innovation Project, Japan Science and Technology Agency, 4-6-1 Komaba, Meguro-ku, 153-8505 Tokyo (Japan)

    2015-07-06

    In this paper, we provide a characterization of truly free-standing proteinaceous structures with submicron feature sizes depending on the fabrication conditions by model-based analysis. Protein cross-linking of bovine serum albumin is performed by direct laser writing and two-photon excitation of flavin adenine dinucleotide. We analyze the obtainable fabrication resolution and required threshold energy for polymerization. The applied polymerization model allows prediction of fabrication conditions and resulting fabrication size, alleviating the application of proteinaceous structure fabrication.

  6. Differential effects of hydrogen peroxide on indices of endothelial cell function

    OpenAIRE

    1984-01-01

    The responses of pig aortic endothelial cells to sublethal doses of potentially toxic stimuli were investigated by monitoring K+ efflux, prostaglandin production, and the release of cytoplasmic purines. Xanthine plus xanthine oxidase reversibly stimulated these three parameters of endothelial cell function at doses that were not cytotoxic, as measured by chromium release, adenine uptake, and vital dye exclusion. The effects of xanthine plus xanthine oxidase were inhibited by catalase but not ...

  7. Molecular characterization of the GCN4-DNA complex.

    OpenAIRE

    Gartenberg, M.R.; Ampe, C.; Steitz, T A; Crothers, D M

    1990-01-01

    We report studies of the DNA complex formed by GCN4, a transcriptional activator of eukaryotic amino acid biosynthetic operons. The DNA thermodynamic binding domain, defined by primer extension analysis, spans at least 18 base pairs, a site much larger than the 9-base-pair consensus defined by homology with naturally occurring binding sites. Chemical modification experiments reveal multiple sites of protein-DNA contact: methylation of any guanine N-7 or adenine N-3, ethylation of any phosphat...

  8. Halbleiternanopartikel-modifizierte Elektrode zum Nachweis von Substraten von NADH-abhängigen Enzymreaktionen

    OpenAIRE

    Schubert, Kirsten; Khalid, Waqas; Zhao, Yue; J. Parak, Wolfgang; Lisdat, Fred

    2010-01-01

    Es wurde ein Elektrodensystem entwickelt, das aufbauend auf Halbleiternanopartikeln (so genannte Quantenpunkte) die sensitive Detektion des Enzymkofaktors NADH (nicotinamide adenine dinucleotide) erlaubt. Kolloidale halbleitende CdSe/ZnS-Nanokristalle sind durch ein Dithiol über Chemisorption an Gold gebunden. Das Stromsignal kann durch die Beleuchtung der Quantenpunkt modifizierten Oberfläche beeinflusst werden. Durch Photoanregung entstehen Elektron-Loch- Paare in den Nanopartikeln, die als...

  9. Nucleotide Capacitance Calculation for DNA Sequencing

    OpenAIRE

    Lu, Jun-Qiang; Zhang, X.-G.

    2008-01-01

    Using a first-principles linear response theory, the capacitance of the DNA nucleotides, adenine, cytosine, guanine, and thymine, are calculated. The difference in the capacitance between the nucleotides is studied with respect to conformational distortion. The result suggests that although an alternate current capacitance measurement of a single-stranded DNA chain threaded through a nanogap electrode may not be sufficient to be used as a standalone method for rapid DNA sequencing, the capaci...

  10. Regulation of substrate utilization in the flight muscle of the locust, Locusta migratoria, during flight

    OpenAIRE

    Worm, R.A.A.; Beenakkers, A.M.Th.

    1980-01-01

    The concentrations of metabolites involved in carbohydrate metabolizing pathways, of amino acids and adenine nucleotides in the flight muscles of Locusta migratoria were determined during a fligt of 2 hr. During the first 15 min of flight, glycogen and glucose concentrations decreased to reach approximately constant levels. The concentration of glucose-6-phosphate increased rapidly. After an initial rise the concentration of fructose-1, 6-diphosphate, dihydroxyacetone phosphate and pyruvate r...

  11. Atomic Structures of the Molecular Components in DNA and RNA based on Bond Lengths as Sums of Atomic Radii

    OpenAIRE

    Heyrovska, Raji

    2007-01-01

    The interpretation by the author in recent years of bond lengths as sums of the relevant atomic or ionic radii has been extended here to the bonds in the skeletal structures of adenine, guanine, thymine, cytosine, uracil, ribose, deoxyribose and phosphoric acid. On examining the bond length data in the literature, it has been found that the averages of the bond lengths are close to the sums of the corresponding atomic covalent radii of carbon, nitrogen, oxygen, hydrogen and phosphorus. Thus, ...

  12. Enhanced superoxide release and elevated protein kinase C activity in neutrophils from diabetic patients: association with periodontitis

    OpenAIRE

    Karima, M; Kantarci, A.; Ohira, T; Hasturk, H.; Jones, V. L.; Nam, B-H.; Malabanan, A.; Trackman, P.C.; Badwey, J A; Van Dyke, T. E.

    2005-01-01

    Inflammation and oxidative stress are important factors in the pathogenesis of diabetes and contribute to the pathogenesis of diabetic complications. Periodontitis is an inflammatory disease that is characterized by increased oxidative stress, and the risk for periodontitis is increased significantly in diabetic subjects. In this study, we examined the superoxide (O2−)-generating reduced nicotinamide adenine dinucleotide phosphate-oxidase complex and protein kinase C (PKC) activity in neutrop...

  13. Purification and characterization of a Bacillus megaterium disulfide reductase specific for disulfides containing pantethine 4',4"-diphosphate.

    OpenAIRE

    Swerdlow, R D; Setlow, P

    1983-01-01

    An NADH-linked disulfide reductase specific for disulfides containing pantethine 4',4"-diphosphate moieties was purified 23,000-fold to homogeneity from spores of Bacillus megaterium. The enzyme had a native molecular weight of 122,000 with two apparently identical subunits, contained one molecule of flavin adenine dinucleotide per subunit, and was inhibited by the vicinal dithiol reagent arsenite. The enzyme was active only on disulfides containing pantethine 4',4"-diphosphate moieties, incl...

  14. Antibiotic, cytotoxic and enzyme inhibitory activity of crude extracts from Brazilian marine invertebrates Atividade antibiótica, citotóxica e de inibição enzimática de extratos brutos de invertebrados marinhos do Brasil

    OpenAIRE

    Mirna H.R. Seleghim; Simone P. Lira; Miriam H. Kossuga; Tatiana Batista; Roberto G. S. Berlinck; Eduardo Hajdu; Guilherme Muricy; Rosana M. da Rocha; Gislene G. F. do Nascimento; Marcio Silva; Eli F. Pimenta; Thiemann, Otávio H.; Glaucius Oliva; Bruno C. Cavalcanti; Claudia Pessoa

    2007-01-01

    Herein we present the results of a screening with 349 crude extracts of Brazilian marine sponges, ascidians, bryozoans and octocorals, against 16 strains of susceptible and antibiotic-resistant bacteria, one yeast (Candida albicans), Mycobacterium tuberculosis H37Rv, three cancer cell lines MCF-7 (breast), B16 (murine melanoma ) and HCT8 (colon), and Leishmania tarentolae adenine phosphoribosyl transferase (L-APRT) enzyme. Less than 15% of marine sponge crude extracts displayed antibacterial ...

  15. Cell Life Versus Cell Longevity: The Mysteries Surrounding the NAD+ Precursor Nicotinamide

    OpenAIRE

    Li, Faqi; Chong, Zhao Zhong; Maiese, Kenneth

    2006-01-01

    Nicotinamide, the amide form of niacin (vitamin B3), is the precursor for the coenzyme β-nicotinamide adenine dinucleotide (NAD+) and plays a significant role during the enhancement of cell survival as well as cell longevity. Yet, these abilities of nicotinamide appear to be diametrically opposed. Here we describe the development of nicotinamide as a novel agent that is critical for modulating cellular metabolism, plasticity, longevity, and inflammatory microglial function as well as for infl...

  16. Poly (ADP-ribose) synthetase inhibitor has a heart protective effect in a rat model of experimental sepsis

    OpenAIRE

    Zhang, Lianshuang; Yao, Jinpeng; Wang, Xifeng; Li, Hongxing; Liu, Tongshen; Zhao, Wei

    2015-01-01

    The aim of this study is to investigate whether PARP inhibitor could reduce cell apoptosis and injury in the heart during sepsis. Materials and methods: 60 healthy male Sprague-Dawley (SD) rats were randomly divided into 4 groups---sham group, modal group, 3-AB pretreatment group and 3-AB treatment group, 15 rats per group. The cecal ligation and puncture (CLP) model of sepsis was used. The following were determined--levels of malondialdehyde (MDA), ATP and nicotinamide adenine dinucleotide (...

  17. A-T碱基对单羟基自由基加成产物的单电子氧化还原性质%One-Electron Redox Characteristics of One-Hydroxyl Radical Adducts of A-T Base Pairs

    Institute of Scientific and Technical Information of China (English)

    侯若冰; 孙彦丽; 王贝贝

    2012-01-01

    采用密度泛函理论在B3LYP/DZP++//B3LYP/6-31 ++G(d,p)水平上研究A-T碱基对的单羟基加成产物的氧化还原性质.计算表明,所有8种加成复合物都表现出显著的氧化性,但其还原性却很弱.加成复合物AC2-T、AC4-T、AC5-T的俘获电子诱发T碱基N3位上的H原子向A碱基的N1位迁移,产生这种氢迁移的根源在于A碱基俘获电子后电子密度较大,有利于在A碱基上形成新的N-H键.%The one-electron redox characteristics of one-hydroxyl radical adducts of adenine-thymine base pairs were calculated using density functional theory at the B3LYP/DZP++//B3LYP/6-31 ++G(d,p) level. The computational results indicate that all eight adducts are strong oxidizing agents and very weak reducing agents. For the Ac2-T, Aw-T, and Ac5-T adducts electron capture causes a hydrogen atom migration from the N3 site of thymine to the N1 site of adenine. The hydrogen atom transfer reactions in the anion adducts are attributable to a higher electron density of the adenine moiety. The higher electron density favors the formation of a new N -H bond on the adenine base.

  18. Pokeweed Antiviral Protein: Its Cytotoxicity Mechanism and Applications in Plant Disease Resistance

    OpenAIRE

    Rong Di; Tumer, Nilgun E.

    2015-01-01

    Pokeweed antiviral protein (PAP) is a 29 kDa type I ribosome inactivating protein (RIP) found in pokeweed plants. Pokeweed produces different forms of PAP. This review focuses on the spring form of PAP isolated from Phytolacca americana leaves. PAP exerts its cytotoxicity by removing a specific adenine from the α-sarcin/ricin loop of the large ribosomal RNA. Besides depurination of the rRNA, PAP has additional activities that contribute to its cytotoxicity. The mechanism of PAP cytotoxicity i...

  19. Does swimming exercise affect experimental chronic kidney disease in rats treated with gum acacia?

    Directory of Open Access Journals (Sweden)

    Badreldin H Ali

    Full Text Available Different modes of exercise are reported to be beneficial in subjects with chronic kidney disease (CKD. Similar benefits have also been ascribed to the dietary supplement gum acacia (GA. Using several physiological, biochemical, immunological, and histopathological measurements, we assessed the effect of swimming exercise (SE on adenine-induced CKD, and tested whether SE would influence the salutary action of GA in rats with CKD. Eight groups of rats were used, the first four of which were fed normal chow for 5 weeks, feed mixed with adenine (0.25% w/w to induce CKD, GA in the drinking water (15% w/v, or were given adenine plus GA, as above. Another four groups were similarly treated, but were subjected to SE during the experimental period, while the first four groups remained sedentary. The pre-SE program lasted for four days (before the start of the experimental treatments, during which the rats were made to swim for 5 to 10 min, and then gradually extended to 20 min per day. Thereafter, the rats in the 5th, 6th, 7th, and 8th groups started to receive their respective treatments, and were subjected to SE three days a week for 45 min each. Adenine induced the typical signs of CKD as confirmed by histopathology, and the other measurements, and GA significantly ameliorated all these signs. SE did not affect the salutary action of GA on renal histology, but it partially improved some of the above biochemical and physiological analytes, suggesting that addition of this mode of exercise to GA supplementation may improve further the benefits of GA supplementation.

  20. ATP Freisetzung aus neutrophilen Granulozyten durch "Connexin 43 hemichannels"

    OpenAIRE

    Küper, Natalie

    2008-01-01

    Extracellular ATP liberated during hypoxia and inflammation can either signal directly on purinergic receptors or can activate adenosine receptors following phosphohydrolysis to adenosine. Given the association of polymorphonuclear leukocytes (PMNs) with adenine-nucleotide/nucleoside signaling in the inflammatory milieu, we hypothesized that PMNs are a source of extracellular ATP. Initial studies using high-performance liquid chromatography and luminometric ATP detection assays revealed that ...

  1. Nuclear quadrupole resonance of 14N and 2H in pyrimidines, purines, and their nucleosides

    Science.gov (United States)

    Rabbani, S. R.; Edmonds, D. T.; Gosling, P.

    Using nuclear quadrupole double-resonance techniques, nitrogen-14 and deuterium nuclear quadrupole coupling constants and asymmetry parameters have been measured in uracil, 5-bromouracil, cytosine, adenine, xanthine, hypoxanthine, their nucleosides, 2-aminopyrimidine, and benzimidazole. Zeeman studies and the detection of the simultaneous transitions of neighboring nuclei allowed in many cases a complete assignment of the observed spectral lines to particular 14N and 2D sites.

  2. Fabrication of submicron proteinaceous structures by direct laser writing

    International Nuclear Information System (INIS)

    In this paper, we provide a characterization of truly free-standing proteinaceous structures with submicron feature sizes depending on the fabrication conditions by model-based analysis. Protein cross-linking of bovine serum albumin is performed by direct laser writing and two-photon excitation of flavin adenine dinucleotide. We analyze the obtainable fabrication resolution and required threshold energy for polymerization. The applied polymerization model allows prediction of fabrication conditions and resulting fabrication size, alleviating the application of proteinaceous structure fabrication

  3. Histidine 21 is at the NAD+ binding site of diphtheria toxin.

    OpenAIRE

    Papini, E; Schiavo, G; Sandoná, D.; Rappuoli, R; C. Montecucco

    1989-01-01

    Treatment of fragment A chain of diphtheria toxin (DT-A) with diethylpyrocarbonate modifies His-21, the single histidine residue present in the chain, without alteration of other residues. Parallel to histidine modification, NAD+ binding and the NAD-glycohydrolase and ADP-ribosyltransferase activities of DT-A are lost. Both NAD+ and adenosine are very effective in protecting DT-A from histidine modification and in preserving its biological properties, while adenine is ineffective. Reversal of...

  4. Degradation of cytokinins by maize cytokinin dehydrogenase is mediated by free radicals generated by enzymatic oxidation of natural benzoxazinones

    OpenAIRE

    Frébortová, J. (Jitka); Novák, O.; Frébort, I. (Ivo); Jorda, R. (Radek)

    2010-01-01

    Hydroxamic acid 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-one (DIMBOA) was isolated from maize phloem sap as a compound enhancing the degradation of isopentenyl adenine by maize cytokinin dehydrogenase (CKX), after oxidative conversion by either laccase or peroxidase. Laccase and peroxidase catalyze oxidative cleavage of DIMBOA to 4-nitrosoresorcinol-1-monomethyl ether (coniferron), which serves as a weak electron acceptor of CKX. The oxidation of DIMBOA and coniferron generates transitional fre...

  5. Targeting aspartate aminotransferase in breast cancer

    OpenAIRE

    Thornburg, Joshua Marshall; Nelson, Kristin K; Clem, Brian F.; Lane, Andrew N.; Arumugam, Sengodagounder; Simmons, Allan; Eaton, John W.; Telang, Sucheta; Chesney, Jason

    2008-01-01

    Introduction Glycolysis is increased in breast adenocarcinoma cells relative to adjacent normal cells in order to produce the ATP and anabolic precursors required for survival, growth and invasion. Glycolysis also serves as a key source of the reduced form of cytoplasmic nicotinamide adenine dinucleotide (NADH) necessary for the shuttling of electrons into mitochondria for electron transport. Lactate dehydrogenase (LDH) regulates glycolytic flux by converting pyruvate to lactate and has been ...

  6. Arginine ADP-ribosylation mechanism based on structural snapshots of iota-toxin and actin complex

    OpenAIRE

    Tsurumura, Toshiharu; Tsumori, Yayoi; Qiu, Hao; Oda, Masataka; Sakurai, Jun; Nagahama, Masahiro; Tsuge, Hideaki

    2012-01-01

    Clostridium perfringens iota-toxin (Ia) mono-ADP ribosylates Arg177 of actin, leading to cytoskeletal disorganization and cell death. To fully understand the reaction mechanism of arginine-specific mono-ADP ribosyl transferase, the structure of the toxin-substrate protein complex must be characterized. Recently, we solved the crystal structure of Ia in complex with actin and the nonhydrolyzable NAD+ analog βTAD (thiazole-4-carboxamide adenine dinucleotide); however, the structures of the NAD+...

  7. NAD+-Dependent Deacetylase Hst1p Controls Biosynthesis and Cellular NAD+ Levels in Saccharomyces cerevisiae

    OpenAIRE

    Bedalov, Antonio; Hirao, Maki; Posakony, Jeffrey; Nelson, Melisa; Simon, Julian A.

    2003-01-01

    Nicotine adenine dinucleotide (NAD+) performs key roles in electron transport reactions, as a substrate for poly(ADP-ribose) polymerase and NAD+-dependent protein deacetylases. In the latter two processes, NAD+ is consumed and converted to ADP-ribose and nicotinamide. NAD+ levels can be maintained by regeneration of NAD+ from nicotinamide via a salvage pathway or by de novo synthesis of NAD+ from tryptophan. Both pathways are conserved from yeast to humans. We describe a critical role of the ...

  8. Genetic Ablation of CD38 Protects against Western Diet-Induced Exercise Intolerance and Metabolic Inflexibility

    OpenAIRE

    Shian-Huey Chiang; W. Wallace Harrington; Guizhen Luo; Naphtali O. Milliken; John C Ulrich; Jing Chen; Rajpal, Deepak K.; Ying Qian; Tiffany Carpenter; Rusty Murray; Robert S Geske; Stimpson, Stephen A.; Kramer, Henning F.; Curt D Haffner; J David Becherer

    2015-01-01

    Nicotinamide adenine dinucleotide (NAD+) is a key cofactor required for essential metabolic oxidation-reduction reactions. It also regulates various cellular activities, including gene expression, signaling, DNA repair and calcium homeostasis. Intracellular NAD+ levels are tightly regulated and often respond rapidly to nutritional and environmental changes. Numerous studies indicate that elevating NAD+ may be therapeutically beneficial in the context of numerous diseases. However, the role of...

  9. Association between NADPH Oxidase p22phox C242T Polymorphism and Ischemic Cerebrovascular Disease: A Meta-Analysis

    OpenAIRE

    Li, Bing-Hu; Zhang, Li-li; Zhang, Bei-Bei; Yin, Yan-Wei; Dai, Li-Meng; Pi, Yan; Guo, Lu; Chang-yue GAO; Fang, Chuan-Qin; Wang, Jing-Zhou; Li, Jing-Cheng

    2013-01-01

    Background Epidemiological studies have evaluated the association between nicotinamide adenine dinucleotide phosphate (NADPH) oxidase p22phox C242T polymorphism and risk of ischemic cerebrovascular disease (ICVD), but the results remain inconclusive. This meta-analysis was therefore designed to clarify these controversies. Methodology/Principal Findings Systematic searches of electronic databases Embase, PubMed and Web of Science, as well as hand searching of the references of identified arti...

  10. Genetic Control of Biosynthesis and Transport of Riboflavin and Flavin Nucleotides and Construction of Robust Biotechnological Producers†

    OpenAIRE

    Abbas, Charles A; Andriy A Sibirny

    2011-01-01

    Summary: Riboflavin [7,8-dimethyl-10-(1′-d-ribityl)isoalloxazine, vitamin B2] is an obligatory component of human and animal diets, as it serves as the precursor of flavin coenzymes, flavin mononucleotide, and flavin adenine dinucleotide, which are involved in oxidative metabolism and other processes. Commercially produced riboflavin is used in agriculture, medicine, and the food industry. Riboflavin synthesis starts from GTP and ribulose-5-phosphate and proceeds through pyrimidine and pterid...

  11. Angiotensin II induces Fat1 expression/activation and vascular smooth muscle cell migration via Nox1-dependent reactive oxygen species generation

    OpenAIRE

    Bruder-Nascimento, T; Chinnasamy, P; Riascos-Bernal, DF; Cau, SB; Callera, GE; Touyz, RM; Tostes, RC; Sibinga, NES

    2014-01-01

    Fat1 is an atypical cadherin that controls vascular smooth muscle cell (VSMC) proliferation and migration. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 1 (Nox1) is an important source of reactive oxygen species (ROS) in VSMCs. Angiotensin II (Ang II) induces the expression and/or activation of both Fat1 and Nox1 proteins. This study tested the hypothesis that Ang II-induced Fat1 activation and VSMC migration are mediated by Nox1-dependent ROS generation and redox signaling. Stu...

  12. DNA Charge Transport: Conformationally Gated Hopping through Stacked Domains

    OpenAIRE

    O'Neill, Melanie A.; Barton, Jacqueline K.

    2004-01-01

    The role of base motions in delocalization and propagation of charge through double helical DNA must be established experimentally and incorporated into mechanistic descriptions of DNA-mediated charge transport (CT). Here, we address these fundamental issues by examining the temperature dependence of the yield of CT between photoexcited 2-aminopurine (Ap*) and G through DNA bridges of varied length and sequence. DNA assemblies (35-mers) were constructed containing adenine bridges Ap(A)_nG (n ...

  13. Solvent effects on charge spatial extent in DNA and implications for transfer.

    OpenAIRE

    Mantz, Y. A.; Gervasio, F. L.; Laino, T.; Parrinello, M.

    2007-01-01

    To clarify the role played by water in facilitating long-range DNA charge transport, carefully designed, state-of-the-art, self-interaction corrected density-functional quantum mechanical and molecular mechanical (SIC-QM/MM) simulations are performed for the first time on two ionized adenine:thymine bridge models in explicit water solvent at finite temperature. For random solvent configurations, the charge is partially delocalized. However, a charge localization on different, well-separated a...

  14. Liquid Chromatography-Mass Spectrometry Interface for Detection of Extraterrestrial Organics

    Science.gov (United States)

    Southard, Adrian E.; Getty, Stephanie A.; Balvin, Manuel; Cook, Jamie E.; Espiritu, Ana Mellina; Kotecki, Carl; Towner, Deborah W.; Dworkin, J. P.; Glavin, Daniel P.; Mahaffy, Paul R.; Ferrance, J.

    2014-01-01

    The OASIS (Organics Analyzer for Sampling Icy surfaces) microchip enables electrospray or thermospray of analyte for subsequent analysis by the OASIS time-of-flight mass spectrometer. Electrospray of buffer solution containing the nucleobase adenine was performed using the microchip and detected by a commercial time-of-flight mass spectrometer. Future testing of thermospray and electrospray capability will be performed using a test fixture and vacuum chamber developed especially for optimization of ion spray at atmosphere and in low pressure environments.

  15. Multiple Evolutionary Selections Involved in Synonymous Codon Usages in the Streptococcus agalactiae Genome

    OpenAIRE

    Yan-Ping Ma; Hao Ke; Zhi-Ling Liang; Zhen-Xing Liu; Le Hao; Jiang-Yao Ma; Yu-Gu Li

    2016-01-01

    Streptococcus agalactiae is an important human and animal pathogen. To better understand the genetic features and evolution of S. agalactiae, multiple factors influencing synonymous codon usage patterns in S. agalactiae were analyzed in this study. A- and U-ending rich codons were used in S. agalactiae function genes through the overall codon usage analysis, indicating that Adenine (A)/Thymine (T) compositional constraints might contribute an important role to the synonymous codon usage patte...

  16. Moderate exercise training promotes adaptations in coronary blood flow and adenosine production in normotensive rats

    Directory of Open Access Journals (Sweden)

    Fernanda R. Roque

    2011-01-01

    Full Text Available OBJECTIVES: Aerobic exercise training prevents cardiovascular risks. Regular exercise promotes functional and structural adaptations that are associated with several cardiovascular benefits. The aim of this study is to investigate the effects of swimming training on coronary blood flow, adenosine production and cardiac capillaries in normotensive rats. METHODS: Wistar rats were randomly divided into two groups: control (C and trained (T. An exercise protocol was performed for 10 weeks and 60 min/day with a tail overload of 5% bodyweight. Coronary blood flow was quantified with a color microsphere technique, and cardiac capillaries were quantified using light microscopy. Adenine nucleotide hydrolysis was evaluated by enzymatic activity, and protein expression was evaluated by western blot. The results are presented as the means ± SEMs (p<0.05. RESULTS: Exercise training increased the coronary blood flow and the myocardial capillary-to-fiber ratio. Moreover, the circulating and cardiac extracellular adenine nucleotide hydrolysis was higher in the trained rats than in the sedentary rats due to the increased activity and protein expression of enzymes, such as E-NTPDase and 59- nucleotidase. CONCLUSIONS: Swimming training increases coronary blood flow, number of cardiac capillaries, and adenine nucleotide hydrolysis. Increased adenosine production may be an important contributor to the enhanced coronary blood flow and angiogenesis that were observed in the exercise-trained rats; collectively, these results suggest improved myocardial perfusion.

  17. Structure-function relationship of a plant NCS1 member - Homology modeling and mutagenesis identified residues critical for substrate specificity of PLUTO, a nucleobase transporter from arabidopsis

    KAUST Repository

    Witz, Sandra

    2014-03-12

    Plastidic uracil salvage is essential for plant growth and development. So far, PLUTO, the plastidic nucleobase transporter from Arabidopsis thaliana is the only known uracil importer at the inner plastidic membrane which represents the permeability barrier of this organelle. We present the first homology model of PLUTO, the sole plant NCS1 member from Arabidopsis based on the crystal structure of the benzyl hydantoin transporter MHP1 from Microbacterium liquefaciens and validated by molecular dynamics simulations. Polar side chains of residues Glu-227 and backbones of Val-145, Gly-147 and Thr-425 are proposed to form the binding site for the three PLUTO substrates uracil, adenine and guanine. Mutational analysis and competition studies identified Glu-227 as an important residue for uracil and to a lesser extent for guanine transport. A differential response in substrate transport was apparent with PLUTO double mutants E227Q G147Q and E227Q T425A, both of which most strongly affected adenine transport, and in V145A G147Q, which markedly affected guanine transport. These differences could be explained by docking studies, showing that uracil and guanine exhibit a similar binding mode whereas adenine binds deep into the catalytic pocket of PLUTO. Furthermore, competition studies confirmed these results. The present study defines the molecular determinants for PLUTO substrate binding and demonstrates key differences in structure-function relations between PLUTO and other NCS1 family members. 2014 Witz et al.

  18. Influence of Growth Regulators on Callogenesis and Somatic Embryo Development in Date Palm (Phoenix dactylifera L. Sahelian Cultivars

    Directory of Open Access Journals (Sweden)

    Djibril Sané

    2012-01-01

    Full Text Available This study provides a physiological analysis of somatic embryogenesis in four elite cultivars of date palms: Ahmar, Amsekhsi, Tijib, and Amaside, from the initial callogenesis to establishment and proliferation of embryogenic suspension cultures. Somatic embryos development and in vitro plants rooting were also studied. For each step, auxins and cytokinins concentrations were optimised. The primary callogenesis from leaf explants of seedlings appeared highly dependent on genotype. Ahmar (80% and Amsekhsi (76% appeared highly callogenic, whereas Tijib (10% and Amaside (2% produced low amounts of calluses. 2,4-Dichlorophenoxyacetic acid appeared favorable to the induction of primary callogenesis and its effect was enhanced by the addition of benzyl adenine or adenine sulfate. Secondary friable calli obtained from chopped granular calli were used to initiate embryogenic cell suspensions in media supplied with 2,4-dichlorophenoxyacetic acid. Suspension cultures showed a growth rate of fourfold after four subcultures in presence of 2,4-dichlorophenoxyacetic acid 2 mg/L. Our results showed that a seven-day transitory treatment with benzyl adenine 0,5 mg/L was necessary to optimize embryos development. Naphthalene acetic acid induced the development of primary orthogravitropic roots during embryos germination. The comparison with cytofluorometry of nuclear DNA amounts showed no significant difference in ploidy level between regenerated plants and seedlings.

  19. Structure-function relationship of a plant NCS1 member--homology modeling and mutagenesis identified residues critical for substrate specificity of PLUTO, a nucleobase transporter from Arabidopsis.

    Science.gov (United States)

    Witz, Sandra; Panwar, Pankaj; Schober, Markus; Deppe, Johannes; Pasha, Farhan Ahmad; Lemieux, M Joanne; Möhlmann, Torsten

    2014-01-01

    Plastidic uracil salvage is essential for plant growth and development. So far, PLUTO, the plastidic nucleobase transporter from Arabidopsis thaliana is the only known uracil importer at the inner plastidic membrane which represents the permeability barrier of this organelle. We present the first homology model of PLUTO, the sole plant NCS1 member from Arabidopsis based on the crystal structure of the benzyl hydantoin transporter MHP1 from Microbacterium liquefaciens and validated by molecular dynamics simulations. Polar side chains of residues Glu-227 and backbones of Val-145, Gly-147 and Thr-425 are proposed to form the binding site for the three PLUTO substrates uracil, adenine and guanine. Mutational analysis and competition studies identified Glu-227 as an important residue for uracil and to a lesser extent for guanine transport. A differential response in substrate transport was apparent with PLUTO double mutants E227Q G147Q and E227Q T425A, both of which most strongly affected adenine transport, and in V145A G147Q, which markedly affected guanine transport. These differences could be explained by docking studies, showing that uracil and guanine exhibit a similar binding mode whereas adenine binds deep into the catalytic pocket of PLUTO. Furthermore, competition studies confirmed these results. The present study defines the molecular determinants for PLUTO substrate binding and demonstrates key differences in structure-function relations between PLUTO and other NCS1 family members. PMID:24621654

  20. 大鼠高尿酸血症模型的建立%Establishment of Hyperuricemia Model in SPF SD Rats

    Institute of Scientific and Technical Information of China (English)

    杨桂梅; 黄胜华; 连希艳; 刘英; 解宇环

    2011-01-01

    Objective To establish a hyperuricetnia model in SD rats. Methods Different doses of adenine, adenine and yeast, adenine and ethambutol and oxonic acid were administrated to the SD rats by oral gavage. Concentrations of serum uric acid, urine nitrogen and creatinine were measured, before and after treatments. Pathological examination of renal tissue were carried out. Results The serum uric acid of the oxonic acid treated groups was increased smoothly, steady and there was no significant renal damage at a long time. Conclusion The oxonic acid is suitable for preparation of hyperuricemia model in SD rats.%目的 建立大鼠高尿酸血症动物模型.方法采用腺嘌呤、腺嘌呤加酵母、腺嘌呤加乙胺丁醇和氧嗪酸钾盐不同剂量口服灌胃,测定实验前后大鼠血清尿酸、尿素氮、肌酐,并进行组织学病理切片观察.结果氧嗪酸钾尿酸升高平稳,并且对肾损伤不严重.结论用氧嗪酸钾建立大鼠高尿酸血症模型较合适.

  1. Evaluation of renographic and metabolic parameters in human kidney transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, A. [Barcelone, Univ. (Spain). Lab. of Biophysics and Bioengineering; Vigues, F.; Franco, E. [Hospital of Bellvitge, Bellvitge (Spain). Service of Urology; Puchal, R. [Hospital of Bellvitge, Bellvitge (Spain). Service of Nuclear Medicine; Bartrons, R.; Ambrosio, S. [Barcelona, Univ. (Spain). Faculty of Odontology, Laboratory of Biochemistry

    1997-03-01

    Background: the aim of this work is to demonstrate that the value of the mean transit time (MTT) obtained from the {sup 99m}Tc-MAG3 renogram deconvolution is related to the levels of adenine nucleotides determined in cortical biopsies from transplanted kidneys. Methods: the functional state was estimated by means of the MTT and the initial height (HO) of the renal retention function obtained from the {sup 99m}Tc-MAG3 renogram deconvolution and by the measure of adenine nucleotides obtained from biopsies. We studied 30 kidney graft recipients, 25 normal functioning grafts (NFG) and 5 with acute tubular necrosis (ATN). Results: the MTT is significantly longer for ATN (p<0.001). The initial uptake values (HO) are significantly lower for ATN (p<0.001). The sum of adenine nucleotides (SAN) is significantly greater for NFG than for ATN (p<0.001). The values of the MTT seem to reflect the energy state of the cells in transplanted kidney. Conclusion: the analysis of MTT may be indicative of the functional metabolic recovery and thus it may be predictive of the renal graft function at least in the same extent than the biochemical analysis of a cortical renal biopsy immediately after blood reperfusion of the tissue.

  2. Probing the interaction of spermine and 1-naphthyl acetyl spermine with DNA polynucleotides: a comparative biophysical and thermodynamic investigation.

    Science.gov (United States)

    Kabir, Ayesha; Kumar, Gopinatha Suresh

    2014-05-01

    The interaction of spermine and its analogue, 1-naphthyl acetyl spermine with four double stranded DNA polynucleotides has been studied to understand the structural and thermodynamic basis of the binding. The efficacy and specificity of DNA binding of this analogue has not yet been revealed. The energetics of the interaction was studied by isothermal titration calorimetry and differential scanning calorimetry. Circular dichroism spectroscopy, UV-thermal melting and ethidium bromide displacement assay have been employed to characterize the association. Circular dichroism studies showed that 1-naphthyl acetyl spermine caused a stronger structural perturbation in the polynucleotides. Among the adenine-thymine polynucleotides the alternating polynucleotide was more preferred by naphthyl acetyl spermine compared to the preference of spermine for the homo sequence. The higher melting stabilization revealed by the optical melting and differential scanning calorimetry results suggested that the binding of 1-naphthyl acetyl spermine increased the melting temperature and the total standard molar enthalpy of the transition of adenine-thymine polynucleotides. Microcalorimetry results revealed that unlike spermine the binding of 1-naphthyl acetyl spermine was endothermic. The interaction was characterized by total enthalpy-entropy compensation and high standard molar heat capacity values. There are differences in the mode of association of 1-naphthyl acetyl spermine and spermine. 1-naphthyl acetyl spermine binds with an enhanced affinity with the adenine-thymine hetero polynucleotide. Thus, the result suggests the importance of polyamine analogues and their ability to interfere with normal polyamine interactions.

  3. Structure-function relationship of a plant NCS1 member--homology modeling and mutagenesis identified residues critical for substrate specificity of PLUTO, a nucleobase transporter from Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Sandra Witz

    Full Text Available Plastidic uracil salvage is essential for plant growth and development. So far, PLUTO, the plastidic nucleobase transporter from Arabidopsis thaliana is the only known uracil importer at the inner plastidic membrane which represents the permeability barrier of this organelle. We present the first homology model of PLUTO, the sole plant NCS1 member from Arabidopsis based on the crystal structure of the benzyl hydantoin transporter MHP1 from Microbacterium liquefaciens and validated by molecular dynamics simulations. Polar side chains of residues Glu-227 and backbones of Val-145, Gly-147 and Thr-425 are proposed to form the binding site for the three PLUTO substrates uracil, adenine and guanine. Mutational analysis and competition studies identified Glu-227 as an important residue for uracil and to a lesser extent for guanine transport. A differential response in substrate transport was apparent with PLUTO double mutants E227Q G147Q and E227Q T425A, both of which most strongly affected adenine transport, and in V145A G147Q, which markedly affected guanine transport. These differences could be explained by docking studies, showing that uracil and guanine exhibit a similar binding mode whereas adenine binds deep into the catalytic pocket of PLUTO. Furthermore, competition studies confirmed these results. The present study defines the molecular determinants for PLUTO substrate binding and demonstrates key differences in structure-function relations between PLUTO and other NCS1 family members.

  4. DNA dynamics in aqueous solution: opening the double helix

    Science.gov (United States)

    Pohorille, A.; Ross, W. S.; Tinoco, I. Jr; MacElroy, R. D. (Principal Investigator)

    1990-01-01

    The opening of a DNA base pair is a simple reaction that is a prerequisite for replication, transcription, and other vital biological functions. Understanding the molecular mechanisms of biological reactions is crucial for predicting and, ultimately, controlling them. Realistic computer simulations of the reactions can provide the needed understanding. To model even the simplest reaction in aqueous solution requires hundreds of hours of supercomputing time. We have used molecular dynamics techniques to simulate fraying of the ends of a six base pair double strand of DNA, [TCGCGA]2, where the four bases of DNA are denoted by T (thymine), C (cytosine), G (guanine), and A (adenine), and to estimate the free energy barrier to this process. The calculations, in which the DNA was surrounded by 2,594 water molecules, required 50 hours of CRAY-2 CPU time for every simulated 100 picoseconds. A free energy barrier to fraying, which is mainly characterized by the movement of adenine away from thymine into aqueous environment, was estimated to be 4 kcal/mol. Another fraying pathway, which leads to stacking between terminal adenine and thymine, was also observed. These detailed pictures of the motions and energetics of DNA base pair opening in water are a first step toward understanding how DNA will interact with any molecule.

  5. A New Method for Estimating Bacterial Abundances in Natural Samples using Sublimation

    Science.gov (United States)

    Glavin, Daniel P.; Cleaves, H. James; Schubert, Michael; Aubrey, Andrew; Bada, Jeffrey L.

    2004-01-01

    We have developed a new method based on the sublimation of adenine from Escherichia coli to estimate bacterial cell counts in natural samples. To demonstrate this technique, several types of natural samples including beach sand, seawater, deep-sea sediment, and two soil samples from the Atacama Desert were heated to a temperature of 500 C for several seconds under reduced pressure. The sublimate was collected on a cold finger and the amount of adenine released from the samples then determined by high performance liquid chromatography (HPLC) with UV absorbance detection. Based on the total amount of adenine recovered from DNA and RNA in these samples, we estimated bacterial cell counts ranging from approx. l0(exp 5) to l0(exp 9) E. coli cell equivalents per gram. For most of these samples, the sublimation based cell counts were in agreement with total bacterial counts obtained by traditional DAPI staining. The simplicity and robustness of the sublimation technique compared to the DAPI staining method makes this approach particularly attractive for use by spacecraft instrumentation. NASA is currently planning to send a lander to Mars in 2009 in order to assess whether or not organic compounds, especially those that might be associated with life, are present in Martian surface samples. Based on our analyses of the Atacama Desert soil samples, several million bacterial cells per gam of Martian soil should be detectable using this sublimation technique.

  6. Optoelectronic studies on heterocyclic bases of deoxyribonucleic acid for DNA photonics

    Energy Technology Data Exchange (ETDEWEB)

    El-Diasty, Fouad, E-mail: fdiasty@yahoo.com; Abdel-Wahab, Fathy

    2015-10-01

    The optoelectronics study of large molecules, particularly π-stacking molecules, such as DNA is really an extremely difficult task. We perform first electronic structure calculations on the heterocyclic bases of 2′-deoxyribonucleic acid based on Lorentz–Fresnel dispersion theory. In the UV–VIS range of spectrum, many of the optoelectronic parameters for DNA four bases namely adenine, guanine, cytosine and thymine are calculated and discussed. The results demonstrate that adenine has the highest hyperpolarizability, whereas thymine has the lowest hyperpolarizability. Cytosine has the lower average oscillator energy and the higher lattice energy. Thymine infers the most stable nucleic base with the lower phonon energy. Thymine also has the highest average oscillator energy and the lower lattice energy. Moreover, the four nucleic acid bases have large band gap energies less than 5 eV with a semiconducting behavior. Guanine shows the smallest band gap and the highest Fermi level energy, whereas adenine elucidates the highest band gap energy. - Highlights: • Optical constants of the four DNA bases are determined. • Band gap energy, Fermi level, average oscillator energy, oscillator strength and lattice energy are calculated and analyzed. • Results provide some useful references for the potential application of the DNA bases in optoelectronic devices.

  7. Factors affecting SFHR gene correction efficiency with single-stranded DNA fragment

    International Nuclear Information System (INIS)

    A 606-nt single-stranded (ss) DNA fragment, prepared by restriction enzyme digestion of ss phagemid DNA, improves the gene correction efficiency by 12-fold as compared with a PCR fragment, which is the conventional type of fragment used in the small fragment homologous replacement method [H. Tsuchiya, H. Harashima, H. Kamiya, Increased SFHR gene correction efficiency with sense single-stranded DNA, J. Gene Med. 7 (2005) 486-493]. To reveal the characteristic features of this gene correction with the ss DNA fragment, the effects on the gene correction in CHO-K1 cells of the chain length, 5'-phosphate, adenine methylation, and transcription were studied. Moreover, the possibility that the ss DNA fragment is integrated into the target DNA was examined with a radioactively labeled ss DNA fragment. The presence of methylated adenine, but not the 5'-phosphate, enhanced the gene correction efficiency, and the optimal length of the ss DNA fragment (∼600 nt) was determined. Transcription of the target gene did not affect the gene correction efficiency. In addition, the target DNA recovered from the transfected CHO-K1 cells was radioactive. The results obtained in this study indicate that length and adenine methylation were important factors affecting the gene correction efficiency, and that the ss DNA fragment was integrated into the double-stranded target DNA

  8. Single nucleotide polymorphism of prolactin gene exon two in ducks of Pekin, Mojosari and Pekin Mojosari crossbred

    Directory of Open Access Journals (Sweden)

    Irma

    2014-05-01

    Full Text Available Prolactin gene plays crucial role in the reproduction and egg production of birds. The objectives of this study were to characterize single nucleotide polymorphism in partial intron and coding region of duck prolactin gene. Blood samples were collected from 168 ducks consisted of 19 Pekin, 36 Mojosari, and 113 of their crossbreds collected from Indonesian Research Institute for Animal Production (IRIAP. Primer pairs for the coding regions in prolactin gene were self designed based on the duck genomic sequence database (GeneBank: AB158611.1. PCR products based on DNA of prolactin gene exon two was amplified approximately 400 bp. There is one base insertion of Adenin at the position of 2001 bp intron two region of duck prolactin. Homology test based on BLAST method indicated 99% identity with duck refference (Code Access GeneBank: AB158611.1. Adenin composition in all of duck samples was higher than refference. Triplet hydrogen bonds between Guanine and Cytosin pairs was higher than those at duplet hydrogen bonds between Adenine and Thymine. All duck samples were homozigous and monomorphyc.

  9. Studies on yeast nucleoside triphosphate-nucleoside diphosphate transphosphorylase (nucleoside diphosphokinase). IV. Steady-state kinetic properties with thymidine nucleotides (including 3'-azido-3'-deoxythymidine analogues).

    Science.gov (United States)

    Kuby, S A; Fleming, G; Alber, T; Richardson, D; Takenaka, H; Hamada, M

    1991-01-01

    A study of the steady-state kinetics of the crystalline brewer's yeast (Saccharomyces carlsbergensis) nucleoside diphosphokinase, with the magnesium complexes of the adenine and thymidine nucleotides as reactants, has led to a postulated kinetic mechanism which proceeds through a substituted enzyme. This agrees with the earlier conclusions of Garces and Cleland [Biochemistry 1969; 8:633-640] who characterized a reaction between the magnesium complexes of the adenine and uridine nucleotides. An advantage of using thymidine nucleotides as reactants is that they permit accurate, rapid and continuous assays of the enzymatic activity in coupled-enzymatic tests. Through measurements of the initial velocities and product inhibition studies, the Michaelis constants, maximum velocities, and inhibition constants could be evaluated for the individual substrates. Competitive substrate inhibition was encountered at relatively high substrate concentrations, which also permitted an evaluation of their ability to act as 'dead-end' inhibitors. The Michaelis constants for the 3'-azido-3'-deoxythymidine (AzT) analogues were also evaluated and, although these values were only somewhat higher than those of their natural substrates, the Km's for the adenine nucleotides as paired substrates were lower and the Vmax's were drastically reduced. The pharmacological implications of these observations are touched upon and extrapolated to the cases where therapeutic doses of AzT may be employed.

  10. A role for the bacterial GATC methylome in antibiotic stress survival.

    Science.gov (United States)

    Cohen, Nadia R; Ross, Christian A; Jain, Saloni; Shapiro, Rebecca S; Gutierrez, Arnaud; Belenky, Peter; Li, Hu; Collins, James J

    2016-05-01

    Antibiotic resistance is an increasingly serious public health threat. Understanding pathways allowing bacteria to survive antibiotic stress may unveil new therapeutic targets. We explore the role of the bacterial epigenome in antibiotic stress survival using classical genetic tools and single-molecule real-time sequencing to characterize genomic methylation kinetics. We find that Escherichia coli survival under antibiotic pressure is severely compromised without adenine methylation at GATC sites. Although the adenine methylome remains stable during drug stress, without GATC methylation, methyl-dependent mismatch repair (MMR) is deleterious and, fueled by the drug-induced error-prone polymerase Pol IV, overwhelms cells with toxic DNA breaks. In multiple E. coli strains, including pathogenic and drug-resistant clinical isolates, DNA adenine methyltransferase deficiency potentiates antibiotics from the β-lactam and quinolone classes. This work indicates that the GATC methylome provides structural support for bacterial survival during antibiotic stress and suggests targeting bacterial DNA methylation as a viable approach to enhancing antibiotic activity. PMID:26998690

  11. Effects of Hypoxanthine Substitution in Peptide Nucleic Acids Targeting KRAS2 Oncogenic mRNA Molecules: Theory and Experiment

    Science.gov (United States)

    Sanders, Jeffrey M.; Wampole, Matthew E.; Chen, Chang-Po; Sethi, Dalip; Singh, Amrita; Dupradeau, François-Yves; Wang, Fan; Gray, Brian D.; Thakur, Mathew L.; Wickstrom, Eric

    2013-01-01

    Genetic disorders can arise from single base substitutions in a single gene. A single base substitution for wild type guanine in the twelfth codon of KRAS2 mRNA occurs frequently to initiate lung, pancreatic, and colon cancer. We have observed single base mismatch specificity in radioimaging of mutant KRAS2 mRNA in tumors in mice by in vivo hybridization with radiolabeled peptide nucleic acid (PNA) dodecamers. We hypothesized that multi-mutant specificity could be achieved with a PNA dodecamer incorporating hypoxanthine, which can form Watson-Crick basepairs with adenine, cytosine, thymine, and uracil. Using molecular dynamics simulations and free energy calculations, we show that hypoxanthine substitutions in PNAs are tolerated in KRAS2 RNA-PNA duplexes where wild type guanine is replaced by mutant uracil or adenine in RNA. To validate our predictions, we synthesized PNA dodecamers with hypoxanthine, and then measured the thermal stability of RNA-PNA duplexes. Circular dichroism thermal melting results showed that hypoxanthine-containing PNAs are more stable in duplexes where hypoxanthine-adenine and hypoxanthine-uracil base pairs are formed than single mismatch duplexes or duplexes containing hypoxanthine-guanine opposition. PMID:23972113

  12. Deamination of amino acids as a source for ammonia production in human skeletal muscle during prolonged exercise

    DEFF Research Database (Denmark)

    Van Hall, Gerrit; van der Vusse, G J; Söderlund, K;

    1995-01-01

    1. The influence of pre-exercise muscle glycogen content on ammonia production, adenine nucleotide breakdown and amino acid metabolism was investigated during prolonged exercise in six subjects having one leg with a normal and one leg with a low muscle glycogen content. One-leg knee-extensor exer......1. The influence of pre-exercise muscle glycogen content on ammonia production, adenine nucleotide breakdown and amino acid metabolism was investigated during prolonged exercise in six subjects having one leg with a normal and one leg with a low muscle glycogen content. One-leg knee......-extensor exercise was performed for 90 min, at a workload of 60-65% of the maximal power output, first with one leg and then with the other. 2. During exercise ammonia was released in gradually increasing amounts and plateaued after 1 h exercise at a rate of approximately 80 mumol min-1. The total ammonia...... production was 9.1 +/- 0.4 and 9.5 +/- 1.4 mmol (kg dry muscle)-1 in the normal and low glycogen content leg, respectively. 3. Levels of muscle phosphocreatine (PC), total adenine nucleotides and inosine monophosphate (IMP) were similar at rest and after 90 min of exercise. 4. Only minor differences were...

  13. Disposable electrochemical DNA biosensor for environmental monitoring of toxicant 2-aminoanthracene in the presence of chlorine in real samples

    Indian Academy of Sciences (India)

    R Motaghed Mazhabi; M Arvand

    2014-07-01

    A simple procedure for the voltammetric detection of the DNA damage using a disposable electrochemical DNA biosensor is reported. The DNA biosensor is assembled by immobilizing the double stranded calf thymus DNA (dsDNA) on the surface of a disposable carbon screen-printed electrode. The interaction of 2-aminoanthracene (2-AA) with calf thymus dsDNA was studied electrochemically based on the oxidation signals of guanine (G) and adenine (A) by using square wave voltammetry (SWV) at screen printed electrode (SPE). The oxidation signals of the guanine and adenine bases, obtained by a square wave voltammetric scan, were used as analytical signal to detect the DNA damage. The presence of this aromatic amine compound with affinity for nucleic acids was measured by its effect on the guanine and adenine oxidation peaks. The response was obtained in the range of 0.05-20 mg L-1 for 2-AA concentration on dsDNA-modified SPE. This test has been used due to its rapid, easy handling and cost effective responses for the toxicity assessment in real water and bleach solution samples.

  14. Unraveling the complexity of the interactions of DNA nucleotides with gold by single molecule force spectroscopy

    Science.gov (United States)

    Bano, Fouzia; Sluysmans, Damien; Wislez, Arnaud; Duwez, Anne-Sophie

    2015-11-01

    Addressing the effect of different environmental factors on the adsorption of DNA to solid supports is critical for the development of robust miniaturized devices for applications ranging from biosensors to next generation molecular technology. Most of the time, thiol-based chemistry is used to anchor DNA on gold - a substrate commonly used in nanotechnology - and little is known about the direct interaction between DNA and gold. So far there have been no systematic studies on the direct adsorption behavior of the deoxyribonucleotides (i.e., a nitrogenous base, a deoxyribose sugar, and a phosphate group) and on the factors that govern the DNA-gold bond strength. Here, using single molecule force spectroscopy, we investigated the interaction of the four individual nucleotides, adenine, guanine, cytosine, and thymine, with gold. Experiments were performed in three salinity conditions and two surface dwell times to reveal the factors that influence nucleotide-Au bond strength. Force data show that, at physiological ionic strength, adenine-Au interactions are stronger, asymmetrical and independent of surface dwell time as compared to cytosine-Au and guanine-Au interactions. We suggest that in these conditions only adenine is able to chemisorb on gold. A decrease of the ionic strength significantly increases the bond strength for all nucleotides. We show that moderate ionic strength along with longer surface dwell period suggest weak chemisorption also for cytosine and guanine.Addressing the effect of different environmental factors on the adsorption of DNA to solid supports is critical for the development of robust miniaturized devices for applications ranging from biosensors to next generation molecular technology. Most of the time, thiol-based chemistry is used to anchor DNA on gold - a substrate commonly used in nanotechnology - and little is known about the direct interaction between DNA and gold. So far there have been no systematic studies on the direct

  15. Glutamate excitotoxicity and Ca(2+)-regulation of respiration: Role of the Ca(2+) activated mitochondrial transporters (CaMCs).

    Science.gov (United States)

    Rueda, Carlos B; Llorente-Folch, Irene; Traba, Javier; Amigo, Ignacio; Gonzalez-Sanchez, Paloma; Contreras, Laura; Juaristi, Inés; Martinez-Valero, Paula; Pardo, Beatriz; Del Arco, Araceli; Satrustegui, Jorgina

    2016-08-01

    Glutamate elicits Ca(2+) signals and workloads that regulate neuronal fate both in physiological and pathological circumstances. Oxidative phosphorylation is required in order to respond to the metabolic challenge caused by glutamate. In response to physiological glutamate signals, cytosolic Ca(2+) activates respiration by stimulation of the NADH malate-aspartate shuttle through Ca(2+)-binding to the mitochondrial aspartate/glutamate carrier (Aralar/AGC1/Slc25a12), and by stimulation of adenine nucleotide uptake through Ca(2+) binding to the mitochondrial ATP-Mg/Pi carrier (SCaMC-3/Slc25a23). In addition, after Ca(2+) entry into the matrix through the mitochondrial Ca(2+) uniporter (MCU), it activates mitochondrial dehydrogenases. In response to pathological glutamate stimulation during excitotoxicity, Ca(2+) overload, reactive oxygen species (ROS), mitochondrial dysfunction and delayed Ca(2+) deregulation (DCD) lead to neuronal death. Glutamate-induced respiratory stimulation is rapidly inactivated through a mechanism involving Poly (ADP-ribose) Polymerase-1 (PARP-1) activation, consumption of cytosolic NAD(+), a decrease in matrix ATP and restricted substrate supply. Glutamate-induced Ca(2+)-activation of SCaMC-3 imports adenine nucleotides into mitochondria, counteracting the depletion of matrix ATP and the impaired respiration, while Aralar-dependent lactate metabolism prevents substrate exhaustion. A second mechanism induced by excitotoxic glutamate is permeability transition pore (PTP) opening, which critically depends on ROS production and matrix Ca(2+) entry through the MCU. By increasing matrix content of adenine nucleotides, SCaMC-3 activity protects against glutamate-induced PTP opening and lowers matrix free Ca(2+), resulting in protracted appearance of DCD and protection against excitotoxicity in vitro and in vivo, while the lack of lactate protection during in vivo excitotoxicity explains increased vulnerability to kainite-induced toxicity in Aralar

  16. Analysis of the Main Nucleosides in Cordyceps Sinensis by LC/ESI-MS

    Directory of Open Access Journals (Sweden)

    Yun-Biao He

    2010-01-01

    Full Text Available A sensitive, selective and reliable liquid chromatography-mass spectrometry coupled with electrospray ionization interface method for simultaneous separation and determination of thymine, adenine, adenosine and cordycepin in Cordyceps sinensis has been established. The optimum separation for these analytes was achieved using a gradient elution system and a 2.0 × 150 mm Shimadzu VP-ODS column. 2-Chloroadenosine was used as internal standard for this assay. [M+H]+ions at m/z 127, 136, 268, 252 and 302 were chosen and selective ion monitoring (SIM mode was used for quantitative analysis of the four main nucleosides. The regression equations were linear in the range of 1.0–117.5 μg·mL-1 for thymine, 1.8-127.0 μg·mL-1 for adenine, 0.6-114.0 μg·mL-1 for adenosine and 0.5-107.5 μg·mL-1 for cordycepin. The limits of quantitation (LOQ and detection (LOD were 1.0 and 0.2 μg·mL-1 for thymine, 1.8 and 0.6 μg·mL-1 for adenine, 0.6 and 0.1 μg·mL-1 for adenosine and 0.5 and 0.1 μg·mL-1 for cordycepin, respectively. The recoveries of the four nucleosides ranged from 98.47 to 99.32%. The developed method was successfully used to determine nucleosides in Cordyceps sinensis from different sources.

  17. Noncovalent interactions of a benzo[a]pyrene diol epoxide with DNA base pairs: insight into the formation of adducts of (+)-BaP DE-2 with DNA.

    Science.gov (United States)

    Hargis, Jacqueline C; Schaefer, Henry F; Houk, K N; Wheeler, Steven E

    2010-02-01

    Noncovalent complexes of a tumorigenic benzo[a]pyrene diol epoxide with the guanine-cytosine (GC) and adenine-thymine (AT) base pairs have been examined computationally. (+)-BaP DE-2 forms covalent adducts with DNA via nucleophilic attack on the (+)-BaP DE-2 epoxide. Computational results predict five thermodynamically accessible complexes of AT with (+)-BaP DE-2 that are compatible with intact DNA. Among these, two are expected to lead to adenine adducts. In the lowest energy AT...(+)-BaP DE-2 complex, which has a gas-phase interaction energy of -20.9 kcal mol(-1), the exocyclic NH(2) of adenine is positioned for backside epoxide attack and formation of a trans adduct. The most energetically favorable complex leading to formation of a cis ring-opened adduct lies only 0.6 kcal mol(-1) higher in energy. For GC...(+)-BaP DE-2, there are only two thermodynamically accessible complexes. The higher-lying complex, bound in the gas phase by 24.4 kcal mol(-1) relative to separated GC and (+)-BaP DE-2, would lead to a trans ring-opened N(2)-guanine adduct. In the global minimum energy GC...(+)-BaP DE-2 complex, bound by 27.3 kcal mol(-1), the exocyclic NH(2) group of cytosine is positioned for cis epoxide addition. However, adducts of (+)-BaP DE-2 with cytosine are rarely observed experimentally. The paucity of cytosine adducts, despite the predicted thermodynamic stability of this GC...(+)-BaP DE-2 complex, is attributed to the electrostatic destabilization of the benzylic cation intermediate thought to precede cis addition.

  18. An improved method of xylose utilization by recombinant Saccharomyces cerevisiae.

    Science.gov (United States)

    Ma, Tien-Yang; Lin, Ting-Hsiang; Hsu, Teng-Chieh; Huang, Chiung-Fang; Guo, Gia-Luen; Hwang, Wen-Song

    2012-10-01

    The aim of this study was to develop a method to optimize expression levels of xylose-metabolizing enzymes to improve xylose utilization capacity of Saccharomyces cerevisiae. A xylose-utilizing recombinant S. cerevisiae strain YY2KL, able to express nicotinamide adenine dinucleotide phosphate, reduced (NADPH)-dependent xylose reductase (XR), nicotinamide adenine dinucleotide (NAD(+))-dependent xylitol dehydrogenase (XDH), and xylulokinase (XK), showed a low ethanol yield and sugar consumption rate. To optimize xylose utilization by YY2KL, a recombinant expression plasmid containing the XR gene was transformed and integrated into the aur1 site of YY2KL. Two recombinant expression plasmids containing an nicotinamide adenine dinucleotide phosphate (NADP(+))-dependent XDH mutant and XK genes were dually transformed and integrated into the 5S ribosomal DNA (rDNA) sites of YY2KL. This procedure allowed systematic construction of an S. cerevisiae library with different ratios of genes for xylose-metabolizing enzymes, and well-grown colonies with different xylose fermentation capacities could be further selected in yeast protein extract (YPX) medium (1 % yeast extract, 2 % peptone, and 2 % xylose). We successfully isolated a recombinant strain with a superior xylose fermentation capacity and designated it as strain YY5A. The xylose consumption rate for strain YY5A was estimated to be 2.32 g/gDCW/h (g xylose/g dry cell weight/h), which was 2.34 times higher than that for the parent strain YY2KL (0.99 g/gDCW/h). The ethanol yield was also enhanced 1.83 times by this novel method. Optimal ratio and expression levels of xylose-metabolizing enzymes are important for efficient conversion of xylose to ethanol. This study provides a novel method that allows rapid and effective selection of ratio-optimized xylose-utilizing yeast strains. This method may be applicable to other multienzyme systems in yeast.

  19. OmpF, a nucleotide-sensing nanoprobe, computational evaluation of single channel activities

    Science.gov (United States)

    Abdolvahab, R. H.; Mobasheri, H.; Nikouee, A.; Ejtehadi, M. R.

    2016-09-01

    The results of highthroughput practical single channel experiments should be formulated and validated by signal analysis approaches to increase the recognition precision of translocating molecules. For this purpose, the activities of the single nano-pore forming protein, OmpF, in the presence of nucleotides were recorded in real time by the voltage clamp technique and used as a means for nucleotide recognition. The results were analyzed based on the permutation entropy of current Time Series (TS), fractality, autocorrelation, structure function, spectral density, and peak fraction to recognize each nucleotide, based on its signature effect on the conductance, gating frequency and voltage sensitivity of channel at different concentrations and membrane potentials. The amplitude and frequency of ion current fluctuation increased in the presence of Adenine more than Cytosine and Thymine in milli-molar (0.5 mM) concentrations. The variance of the current TS at various applied voltages showed a non-monotonic trend whose initial increasing slope in the presence of Thymine changed to a decreasing one in the second phase and was different from that of Adenine and Cytosine; e.g., by increasing the voltage from 40 to 140 mV in the 0.5 mM concentration of Adenine or Cytosine, the variance decreased by one third while for the case of Thymine it was doubled. Moreover, according to the structure function of TS, the fractality of current TS differed as a function of varying membrane potentials (pd) and nucleotide concentrations. Accordingly, the calculated permutation entropy of the TS, validated the biophysical approach defined for the recognition of different nucleotides at various concentrations, pd's and polarities. Thus, the promising outcomes of the combined experimental and theoretical methodologies presented here can be implemented as a complementary means in pore-based nucleotide recognition approaches.

  20. Silver- and gold-mediated nucleobase bonding.

    Science.gov (United States)

    Acioli, Paulo H; Srinivas, Sudha

    2014-08-01

    We report the results of a density functional theory investigation of the bonding of nucleobases mediated by silver and gold atoms in the gas phase. Our calculations use the Becke exchange and Perdew-Wang correlation functional (BPW91) combined with the Stuttgart effective core potentials to represent the valence electrons of gold, silver, and platinum, and the all-electron DGTZVP basis set for C, H, N, and O. This combination was chosen based on tests on the metal atoms and tautomers of adenine, cytosine, and guanine. To establish a benchmark to understand the metal-mediated bonding, we calculated the binding energy of each of the base pairs in their canonical forms. Our calculations show rather strong bonds between the Watson-Crick base pairs when compared with typical values for N-H-N and N-H-O hydrogen bonds. The neutral metal atoms tend to bond near the nitrogen atoms. The effect of the metal atoms on the bonding of nucleobases differs depending on whether or not the metal atoms bond to one of the hydrogen-bonding sites. When the silver or gold atoms bond to a non-hydrogen-bonding site, the effect is a slight enhancement of the cytosine-guanine bonding, but there is almost no effect on the adenine-thymine pairing. The metal atoms can block one of the hydrogen-bonding sites, thus preventing the normal cytosine-guanine and adenine-thymine pairings. We also find that both silver and gold can bond to consecutive guanines in a similar fashion to platinum, albeit with a significantly lower binding energy.