0000000000135250

AUTHOR

Jan Davidsson

showing 4 related works from this author

Visualizing a protein quake with time-resolved X-ray scattering at a free-electron laser

2014

We describe a method to measure ultrafast protein structural changes using time-resolved wide-angle X-ray scattering at an X-ray free-electron laser. We demonstrated this approach using multiphoton excitation of the Blastochloris viridis photosynthetic reaction center, observing an ultrafast global conformational change that arises within picoseconds and precedes the propagation of heat through the protein. This provides direct structural evidence for a 'protein quake': the hypothesis that proteins rapidly dissipate energy through quake-like structural motions. peerReviewed

Photosynthetic reaction centreMaterials scienceProtein ConformationPhysics::OpticsPhycobiliproteinsfrequency vibrational-modesRadiation DosageBiochemistryMolecular physicsArticlelaw.inventionProtein structureX-Ray Diffractionlawddc:570Scattering Small AngleMolecular Biologyta116Quantitative Biology::BiomoleculesScatteringLasersMolecular biophysicsFree-electron laserCell BiologyLaserstructural dynamicsEnergy TransferPicosecondBiophysicsUltrashort pulseBiotechnologyNature methods
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Singlet Excited-State Interactions in Naphthalene-Thymine Dyads

2004

Two thymidine-derived nucleosides 1 and 2 were prepared by attaching a chiral naphthalene to the positions 5′ and 3′ of the sugar. The resulting dyads, which contain key substructures present in drugs and nucleic acids, exhibit different spatial arrangements (transoid or cisoid) of the fluorophore relative to the thymine unit. Emission measurements on these compounds in the presence of ROH molecules revealed a remarkable intramolecular fluorescence quenching for dyad 1. The obtained results are consistent with quenching of the singlet excited state of 1 by hydrogen-bond donor solvents. Thus, a physical deactivation process (vibronically induced internal conversion) would be the pathway resp…

Models MolecularPhotolysisQuenching (fluorescence)ChemistryLasersMolecular ConformationNaphthalenesCrystallography X-RayInternal conversion (chemistry)PhotochemistryFluorescenceAtomic and Molecular Physics and OpticsThyminechemistry.chemical_compoundSpectrometry FluorescenceIntersystem crossingIntramolecular forceExcited stateSpectrophotometry UltravioletSinglet statePhysical and Theoretical ChemistryThymineChemPhysChem
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Photoinduced Electron Transfer Reactions in a Porphyrin−Viologen Complex:  Observation of S2 to S1 Relaxation and Electron Transfer from the S2 State

1999

Photoinduced Energy Transfer Reactions in a Porphyrin-Viologen Complex: Observation of S2 to S1 Relaxation and Electron Transfer from the S2 state

Materials scienceEnergy transferViologenPhotochemistryPorphyrinPhotoinduced electron transferSurfaces Coatings and Filmschemistry.chemical_compoundElectron transferFörster resonance energy transferchemistryMaterials ChemistrymedicineRelaxation (physics)Physical and Theoretical ChemistryProton-coupled electron transfermedicine.drugThe Journal of Physical Chemistry B
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Ultrafast structural changes within a photosynthetic reaction centre

2021

Nature <London> / Physical science 589, 310 - 314 (2021). doi:10.1038/s41586-020-3000-7

0301 basic medicinePhotosynthetic reaction centreChlorophyllModels MolecularklorofylliCytoplasmUbiquinonePhotosynthetic Reaction Center Complex ProteinsElectrons02 engineering and technologyPhotochemistrymedicine.disease_cause530yhteyttäminenbakteeritElectron Transport03 medical and health sciencesElectron transfermedicineMoleculeddc:530BacteriochlorophyllsbioenergetiikkaComputingMilieux_MISCELLANEOUSHyphomicrobiaceaeMultidisciplinaryBinding SitesCrystallography[SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry Molecular Biology/Structural Biology [q-bio.BM]ChemistryBlastochloris viridisLaserskalvot (biologia)PheophytinsBiological membraneVitamin K 2021001 nanoscience & nanotechnologyAcceptor030104 developmental biologyPicosecondFemtosecondsense organsProtons0210 nano-technologyOxidation-Reductionröntgenkristallografia
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