Search results for "Biomolecules"

showing 10 items of 549 documents

Ab initio determination of the electron affinities of DNA and RNA nucleobases

2008

High-level quantum-chemical ab initio coupled-cluster and multiconfigurational perturbation methods have been used to compute the vertical and adiabatic electron affinities of the five canonical DNA and RNA nucleobases: uracil, thymine, cytosine, adenine, and guanine. The present results aim for the accurate determination of the intrinsic electron acceptor properties of the isolated nucleic acid bases as described by their electron affinities, establishing an overall set of theoretical reference values at a level not reported before and helping to rule out less reliable theoretical and experimental data and to calibrate theoretical strategies. Daniel.Roca@uv.es Manuela.Merchan@uv.es Luis.Se…

GuanineAb initioGeneral Physics and AstronomyElectronsAb initio calculations ; Coupled cluster calculations ; DNA ; Electron affinity ; Macromolecules ; Molecular biophysics ; Perturbation theoryPerturbation theoryNucleobasechemistry.chemical_compoundCoupled cluster calculationsComputational chemistryAb initio quantum chemistry methodsComputer SimulationPhysical and Theoretical Chemistry:FÍSICA::Química física [UNESCO]Physics::Biological PhysicsQuantitative Biology::BiomoleculesChemistryUracilDNAMolecular biophysicsQuantitative Biology::GenomicsUNESCO::FÍSICA::Química físicaThymineElectron affinityModels ChemicalMacromoleculesNucleic Acid ConformationQuantum TheoryRNAAb initio calculationsCytosineDNAThe Journal of Chemical Physics
researchProduct

Interaction of iron(II)-heme and artemisinin with a peptide mimic of Plasmodium falciparum HRP-II

2007

Abstract The interaction of heme or heme-artemisinin adducts (heme-art) with different peptides mimicking repeat sequences of the Histidine-Rich-Protein-II of Plasmodium falciparum (PfHRP-II) was investigated. The pseudo-first order rate constants of the coordination of heme or heme-art onto a histidine rich peptide, used as a mimic of PfHRP-II putative heme binding sequence, are of the same order of magnitude, namely 42 and 14 s −1 , respectively. Despite the intrinsic reactivity of the carbonyl at C10 of heme-art toward a hydroxyl function, a peptide containing a serine or threonine residue does not readily react with heme-art adducts. Therefore, a much higher affinity of heme-art compare…

Heme bindingStereochemistryIronPlasmodium falciparumProtozoan ProteinsmalariaPeptide010402 general chemistry01 natural sciencesBiochemistryInorganic Chemistry03 medical and health scienceschemistry.chemical_compoundResidue (chemistry)[ SDV.BBM.BC ] Life Sciences [q-bio]/Biochemistry Molecular Biology/Biomolecules [q-bio.BM]hemozoinAnimals[SDV.BBM.BC]Life Sciences [q-bio]/Biochemistry Molecular Biology/Biochemistry [q-bio.BM]hemeHemealkylationHistidineComputingMilieux_MISCELLANEOUS030304 developmental biologychemistry.chemical_classification0303 health sciencesMolecular StructurebiologyHemozoinMolecular MimicryProteinsPlasmodium falciparumbiology.organism_classificationArtemisininsProtein tertiary structure3. Good health0104 chemical sciencesKineticsModels ChemicalchemistryBiochemistryartemisininPeptidesProtein Binding
researchProduct

Vibrational modes of the stibine molecule

2005

International audience; In this paper, we use the algebraic approach to describe the vibrational modes of stibine molecule (of C3v molecular symmetry group) up to 21 quanta. As the stibine molecule exhibits stretch-bend resonances, we build an algebraic pyramidal coupling operator between stretching modes and bending modes adapted to this molecule. The standard deviation associated to the fit of the vibrational levels is 1.75 cm-1.

High excited levels[ PHYS.QPHY ] Physics [physics]/Quantum Physics [quant-ph]StibineAlgebraic approachVibrational modes01 natural sciencesMolecular physicsHot bandchemistry.chemical_compound[PHYS.QPHY]Physics [physics]/Quantum Physics [quant-ph]0103 physical sciencesMolecular symmetryMoleculeSbH3 moleculePhysics::Chemical PhysicsPhysical and Theoretical Chemistry010306 general physicsSpectroscopyCouplingPhysicsQuantitative Biology::Biomolecules010304 chemical physicsGroup (mathematics)Operator (physics)Atomic and Molecular Physics and OpticschemistryMolecular vibrationJournal of Molecular Spectroscopy
researchProduct

Non-equivalent hyperbolic knots

2002

We construct, for each integer n 3, pairs of non-equivalent hyperbolic knots with the same 2fold and n-fold cyclic branched covers. We also discuss necessary conditions for such pairs of knots to exist.  2001 Elsevier Science B.V. All rights reserved. MSC: primary 57M25; secondary 57M12, 57M50

Hyperbolic knotsPure mathematicsQuantitative Biology::BiomoleculesCyclic branched coversHyperbolic groupSkein relationHyperbolic 3-manifoldOrbifoldsHyperbolic manifoldVolume conjectureMathematics::Geometric TopologyBonahon–Siebenmann decompositionKnot theoryAlgebraIntegerGeometry and TopologyMathematicsTopology and its Applications
researchProduct

Rapid inactivation and proteasome-mediated degradation of OGG1 contribute to the synergistic effect of hyperthermia on genotoxic treatments

2013

Inhibition of DNA repair has been proposed as a mechanism underlying heat-induced sensitization of tumour cells to some anticancer treatments. Base excision repair (BER) constitutes the main pathway for the repair of DNA lesions induced by oxidizing or alkylating agents. Here, we report that mild hyperthermia, without toxic consequences per se, affects cellular DNA glycosylase activities, thus impairing BER. Exposure of cells to mild hyperthermia leads to a rapid and selective inactivation of OGG1 (8-oxoguanine DNA glycosylase) associated with the relocalisation of the protein into a detergent-resistant cellular fraction. Following its inactivation, OGG1 is ubiquitinated and directed to pro…

HyperthermiaProteasome Endopeptidase ComplexPyrrolidinesDNA RepairDNA repairUbiquitin-Protein Ligases[SDV.BC.BC]Life Sciences [q-bio]/Cellular Biology/Subcellular Processes [q-bio.SC]BiochemistryDNA Glycosylases03 medical and health scienceschemistry.chemical_compound0302 clinical medicineUbiquitinEnzyme StabilitymedicineHumans[SDV.BBM.BC]Life Sciences [q-bio]/Biochemistry Molecular Biology/Biochemistry [q-bio.BM]Molecular BiologyComputingMilieux_MISCELLANEOUSCell Proliferation030304 developmental biologyCell Nucleus0303 health sciencesPhotosensitizing AgentsbiologyCell growthUbiquitinationCell BiologyBase excision repairmedicine.diseaseMolecular biology[SDV.BBM.BC]Life Sciences [q-bio]/Biochemistry Molecular Biology/Biomolecules [q-bio.BM]Protein TransportProteasomechemistryDNA glycosylase030220 oncology & carcinogenesisProteolysisCancer researchbiology.proteinHeat-Shock ResponseQuinolizinesDNADNA DamageHeLa Cells
researchProduct

"Table 24" of "Studies of quantum chromodynamics with the ALEPH detector"

1997

Unfolded values of the the mean multiplicity and dispersion of the multiplicity distribution integrated over the full rapidity region.

InclusiveQuantitative Biology::BiomoleculesDISPERSIONE+ E- --> Z0E+ E- ScatteringExclusiveComputer Science::Symbolic ComputationE+ E- --> CHARGED X91.2Computer Science::Distributed Parallel and Cluster ComputingMULT
researchProduct

"Table 3" of "Measurement of the spin density matrix for the rho0, K*(892)0 and Phi produced in Z0 decays."

1997

Helicity density matrices elements. The statistical and systematic errors are combined quadratically.

InclusiveQuantitative Biology::BiomoleculesE+ E- --> PHI XRHOE+ E- Scattering91.2
researchProduct

"Table 18" of "Studies of quantum chromodynamics with the ALEPH detector"

1997

Unfolded charged particle multiplicity distribution giving the probability to have a hadronic Z0 decay with N charged particles.

InclusiveQuantitative Biology::BiomoleculesE+ E- --> Z0E+ E- ScatteringExclusiveHigh Energy Physics::ExperimentE+ E- --> CHARGED X91.2MULT
researchProduct

"Table 6" of "Measurements of the charged particle multiplicity distribution in restricted rapidity intervals"

1995

Unfolded mean charged multiplicity distributions.

InclusiveQuantitative Biology::BiomoleculesE+ E- ScatteringE+ E- --> CHARGED X91.2MULT
researchProduct

"Table 1" of "Measurements of the charged particle multiplicity distribution in restricted rapidity intervals"

1995

Unfolded charged particle multiplicity distribution given the probability to have an hadronic Z0 decay with MULT charged particles.

InclusiveQuantitative Biology::BiomoleculesE+ E- ScatteringHigh Energy Physics::ExperimentE+ E- --> CHARGED X91.2MULT
researchProduct