4pj0
Structure of T.elongatus Photosystem II, rows of dimers crystal packingStructure of T.elongatus Photosystem II, rows of dimers crystal packing
Structural highlights
FunctionPSBA1_THEVB Photosystem II (PSII) is a light-driven water:plastoquinone oxidoreductase that uses light energy to abstract electrons from H(2)O, generating O(2) and a proton gradient subsequently used for ATP formation. It consists of a core antenna complex that captures photons, and an electron transfer chain that converts photonic excitation into a charge separation. The D1/D2 (PsbA/PsbD) reaction center heterodimer binds P680, the primary electron donor of PSII as well as several subsequent electron acceptors.[HAMAP-Rule:MF_01379][1] [2] [3] Publication Abstract from PubMedPhotosystem II (PSII) catalyzes a key step in photosynthesis, the oxidation of water to oxygen. Excellent structural models exist for the dimeric PSII core complex of cyanobacteria, but higher order physiological assemblies readily dissociate when solubilized from the native thylakoid membrane with detergent. Here, we describe the crystallization of PSII from Thermosynechococcus elongatus with a postcrystallization treatment involving extraction of the detergent C12E8. This resulted in a transition from Type II to Type I-like membrane protein crystals and improved diffraction to 2.44 A resolution. The obtained PSII packing in precise rows, interconnected by specific pairs of galactolipids and a loop in the PsbO subunit specific to cyanobacteria, is superimposable with previous electron microscopy images of the thylakoid membrane. The study provides a detailed model of such a superstructure and its organization of light-harvesting pigments with possible implications for the understanding of their efficient use of solar energy. Native-like Photosystem II Superstructure at 2.44 A Resolution through Detergent Extraction from the Protein Crystal.,Hellmich J, Bommer M, Burkhardt A, Ibrahim M, Kern J, Meents A, Muh F, Dobbek H, Zouni A Structure. 2014 Nov 4;22(11):1607-15. doi: 10.1016/j.str.2014.09.007. Epub 2014, Oct 30. PMID:25438669[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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