3KZI

Crystal Structure of Monomeric Form of Cyanobacterial Photosystem II

Summary for 3KZI

• Entry DOI: 10.2210/pdb3kzi/pdb
• Related: 3BZ1 3BZ2
• Descriptor: Photosystem Q(B) protein 1, Photosystem II reaction center protein K, Photosystem II reaction center protein L, ... (34 entities in total)
• Functional Keywords: electron transport photosystem, ps ii, ps2, membrane complex, transmembrane alpha-helix, iron, metal-binding, photosynthesis, photosystem ii, thylakoid, heme, reaction center, manganese, electron transport
• Biological source: Thermosynechococcus elongatus; More
• Cellular location: Cellular thylakoid membrane; Multi-pass membrane protein: P0A444 Q8DHJ2; Cellular thylakoid membrane; Single-pass membrane protein: Q9F1K9 Q8DIN8 Q8DHA7 Q8DIQ0 Q8DJI1 Q8DIP0 Q8DIN9 Q8DJ43 Q8DJZ6; Cellular thylakoid membrane; Peripheral membrane protein; Lumenal side: Q9F1L5 P0A386; Cellular thylakoid membrane; Single-pass membrane protein (By similarity): Q9F1R6 P59087; Cellular thylakoid membrane; Multi-pass membrane protein (By similarity): Q8CM25
• Total number of polymer chains: 19
• Total formula weight: 364392.54

Authors

Gabdulkhakov, A.,Guskov, A.,Broser, M.,Kern, J.,Zouni, A.,Saenger, W. (deposition date: 2009-12-08, release date: 2010-06-16, Last modification date: 2023-11-01)

Primary citation

Broser, M.,Gabdulkhakov, A.,Kern, J.,Guskov, A.,Muh, F.,Saenger, W.,Zouni, A.
Crystal Structure of Monomeric Photosystem II from Thermosynechococcus elongatus at 3.6-A Resolution
J.Biol.Chem., 285:26255-26262, 2010

PubMed Abstract: The membrane-embedded photosystem II core complex (PSIIcc) uses light energy to oxidize water in photosynthesis. Information about the spatial structure of PSIIcc obtained from x-ray crystallography was so far derived from homodimeric PSIIcc of thermophilic cyanobacteria. Here, we report the first crystallization and structural analysis of the monomeric form of PSIIcc with high oxygen evolution capacity, isolated from Thermosynechococcus elongatus. The crystals belong to the space group C222(1), contain one monomer per asymmetric unit, and diffract to a resolution of 3.6 A. The x-ray diffraction pattern of the PSIIcc-monomer crystals exhibit less anisotropy (dependence of resolution on crystal orientation) compared with crystals of dimeric PSIIcc, and the packing of the molecules within the unit cell is different. In the monomer, 19 protein subunits, 35 chlorophylls, two pheophytins, the non-heme iron, the primary plastoquinone Q(A), two heme groups, 11 beta-carotenes, 22 lipids, seven detergent molecules, and the Mn(4)Ca cluster of the water oxidizing complex could be assigned analogous to the dimer. Based on the new structural information, the roles of lipids and protein subunits in dimer formation of PSIIcc are discussed. Due to the lack of non-crystallographic symmetry and the orientation of the membrane normal of PSIIcc perpendicular ( approximately 87 degrees ) to the crystallographic b-axis, further information about the structure of the Mn(4)Ca cluster is expected to become available from orientation-dependent spectroscopy on this new crystal form.

PubMed: 20558739
DOI: 10.1074/jbc.M110.127589

Experimental method

X-RAY DIFFRACTION (3.6 Å)