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Crystal structure of plant photosystem I-LHCI super-complex at 2.8 angstrom resolutionCrystal structure of plant photosystem I-LHCI super-complex at 2.8 angstrom resolution
Structural highlights
FunctionPSAA_PEA PsaA and PsaB bind P700, the primary electron donor of photosystem I (PSI), as well as the electron acceptors A0, A1 and FX. PSI is a plastocyanin-ferredoxin oxidoreductase, converting photonic excitation into a charge separation, which transfers an electron from the donor P700 chlorophyll pair to the spectroscopically characterized acceptors A0, A1, FX, FA and FB in turn. Oxidized P700 is reduced on the lumenal side of the thylakoid membrane by plastocyanin. Publication Abstract from PubMedPhotosynthesis converts solar energy to chemical energy by means of two large pigment-protein complexes: photosystem I (PSI) and photosystem II (PSII). In higher plants, the PSI core is surrounded by a large light-harvesting complex I (LHCI) that captures sunlight and transfers the excitation energy to the core with extremely high efficiency. We report the structure of PSI-LHCI, a 600-kilodalton membrane protein supercomplex, from Pisum sativum (pea) at a resolution of 2.8 angstroms. The structure reveals the detailed arrangement of pigments and other cofactors-especially within LHCI-as well as numerous specific interactions between the PSI core and LHCI. These results provide a firm structural basis for our understanding on the energy transfer and photoprotection mechanisms within the PSI-LHCI supercomplex. Photosynthesis. Structural basis for energy transfer pathways in the plant PSI-LHCI supercomplex.,Qin X, Suga M, Kuang T, Shen JR Science. 2015 May 29;348(6238):989-95. doi: 10.1126/science.aab0214. PMID:26023133[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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