Parameters of the Protein Energy Landscapes of Several Light-Harvesting Complexes Probed via Spectral Hole Growth Kinetics Measurements
| Autor: | Nicoleta Herascu, Alexey Amunts, Michael Seibert, Valter Zazubovich, Klaus-Dieter Irrgang, Rafael Picorel, Mehdi Najafi, Jörg Pieper |
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| Rok vydání: | 2011 |
| Předmět: |
Chlorophyll
Models Molecular Photosystem II Light-Harvesting Protein Complexes Analytical chemistry macromolecular substances Photosystem I Absorption Light-harvesting complex chemistry.chemical_compound Pigment Spinacia oleracea Materials Chemistry Physical and Theoretical Chemistry Protein Structure Quaternary GeneralLiterature_REFERENCE(e.g. dictionaries encyclopedias glossaries) biology Chemistry Peas Photosystem II Protein Complex Energy landscape biology.organism_classification Surfaces Coatings and Films Kinetics Spectrometry Fluorescence Monomer Energy Transfer Chemical physics visual_art Spectral hole burning visual_art.visual_art_medium Spinach Protein Multimerization |
| Zdroj: | Digital.CSIC. Repositorio Institucional del CSIC instname |
| ISSN: | 1520-5207 1520-6106 |
| Popis: | 44 Pag., 2 Tabl. The definitive version is available at: http://pubs.acs.org/journal/jpcbfk The parameters of barrier distributions on the protein energy landscape in the excited electronic state of the pigment/protein system have been determined by means of spectral hole burning for the lowest-energy pigments of CP43 core antenna complex and CP29 minor antenna complex of spinach Photosystem II (PS II) as well as of trimeric and monomeric LHCII complexes transiently associated with the pea Photosystem I (PS I) pool. All of these complexes exhibit sixty to several hundred times lower spectral hole burning yields as compared with molecular glassy solids previously probed by means of the hole growth kinetics measurements. Therefore, the entities (groups of atoms), which participate in conformational changes in protein, appear to be significantly larger and heavier than those in molecular glasses. No evidence of a small (1 cm−1) spectral shift tier of the spectral diffusion dynamics has been observed. Therefore, our data most likely reflect the true barrier distributions of the intact protein and not those related to the interface or surrounding host. Possible applications of the barrier distributions as well as the assignments of low-energy states of CP29 and LHCII are discussed in light of the above results. Research at Concordia University is supported by NSERC and CFI. R.P. would like to thank Spanish MICINN (grant AGL2008-00377). M.S. acknowledges the contribution of the Photosynthetic Systems Program, Chemical Sciences, Geosciences, and Biosciences Division, Basic Energy Sciences, USDOE. J.P. and K.-D.I. gratefully acknowledge support from Deutsche Forschungsgemeinschaft (SFB 429, TP A1, and TP A3, respectively). |
| Databáze: | OpenAIRE |
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