6533b7d4fe1ef96bd126282b
RESEARCH PRODUCT
Ultrafast excitation dynamics of low energy pigments in reconstituted peripheral light-harvesting complexes of photosystem I
Harald PaulsenAlexander N. MelkozernovRobert E. BlankenshipGregory W. SchmidtVolkmar H.r. SchmidSu Linsubject
Time-resolved spectroscopyPhotosystem I0106 biological sciencesAbsorption spectroscopyPhotosynthetic Reaction Center Complex ProteinsLight-Harvesting Protein ComplexesBiophysicsPhotochemistryPhotosystem I01 natural sciences7. Clean energyBiochemistryFluorescence spectroscopyLight-harvesting complexExcitation energy transfer03 medical and health scienceschemistry.chemical_compoundStructural BiologyUltrafast laser spectroscopyGeneticsMolecular BiologyPlant Proteins030304 developmental biology0303 health sciencesPhotosystem I Protein ComplexSpectrophotometry AtomicPigments BiologicalCell BiologyPlantsLHCI-730 heterodimerEnergy TransferchemistryAntennaChlorophyllPicosecondChlorophyll Binding ProteinsLight-harvesting complexTime-resolved spectroscopyDimerization010606 plant biology & botanydescription
AbstractUltrafast dynamics of a reconstituted Lhca4 subunit from the peripheral LHCI-730 antenna of photosystem I of higher plants were probed by femtosecond absorption spectroscopy at 77 K. Intramonomeric energy transfer from chlorophyll (Chl) b to Chl a and energy equilibration between Chl a molecules observed on the subpicosecond time scale are largely similar to subpicosecond energy equilibration processes within LHCII monomers. However, a 5 ps equilibration process in Lhca4 involves unique low energy Chls in LHCI absorbing at 705 nm. These pigments localize the excitation both in the Lhca4 subunit and in LHCI-730 heterodimers. An additional 30–50 ps equilibration process involving red pigments of Lhca4 in the heterodimer, observed by transient absorption and picosecond fluorescence spectroscopy, was ascribed to intersubunit energy transfer.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2000-04-05 | FEBS Letters |