2o01
From Proteopedia
The Structure of a plant photosystem I supercomplex at 3.4 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. Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedAll higher organisms on Earth receive energy directly or indirectly from oxygenic photosynthesis performed by plants, green algae and cyanobacteria. Photosystem I (PSI) is a supercomplex of a reaction centre and light-harvesting complexes. It generates the most negative redox potential in nature, and thus largely determines the global amount of enthalpy in living systems. We report the structure of plant PSI at 3.4 A resolution, revealing 17 protein subunits. PsaN was identified in the luminal side of the supercomplex, and most of the amino acids in the reaction centre were traced. The crystal structure of PSI provides a picture at near atomic detail of 11 out of 12 protein subunits of the reaction centre. At this level, 168 chlorophylls (65 assigned with orientations for Q(x) and Q(y) transition dipole moments), 2 phylloquinones, 3 Fe(4)S(4) clusters and 5 carotenoids are described. This structural information extends the understanding of the most efficient nano-photochemical machine in nature. The structure of a plant photosystem I supercomplex at 3.4 A resolution.,Amunts A, Drory O, Nelson N Nature. 2007 May 3;447(7140):58-63. PMID:17476261[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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