title: Crystallization and preliminary crystallographic studies on the extrinsic 23 kDa protein in the oxygen-evolving complex of photosystem II.
abstract: The extrinsic 23 kDa protein in the oxygen-evolving complex (OEC23 or PsbP) of photosystem II (PS II) helps to retain calcium and chloride ions, which are essential cofactors for the photosynthetic evolution of oxygen. OEC23 is found in the PS II complex from higher plants and green algae, but not in that from cyanobacteria or other ancestral photosynthetic organisms. In order to elucidate the three-dimensional structure and its molecular evolution, OEC23 was crystallized by the hanging-drop vapour-diffusion technique with PEG 4000 as a precipitant. Diffraction data to a resolution of 2.0 A were collected from a native crystal belonging to space group P2(1)2(1)2, with unit-cell parameters a = 91.36, b = 74.15, c = 52.16 A.
authors.affiliation: Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Kitashirakawa, Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Ifuku
authors.forename: Toru
authors.initials: T
authors.lastname: Nakatsu
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kato
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Sato
mesh_terms: D003460:Crystallization; D018360:Crystallography, X-Ray; D018553:Cucumis sativus / Q000201:enzymology; D004926:Escherichia coli / Q000378:metabolism; D007477:Ions; D007700:Kinetics; D010100:Oxygen / Q000378:metabolism; D045332:Photosystem II Protein Complex / Q000737:chemistry*; D010940:Plant Proteins / Q000737:chemistry*; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry; D018724:Spinacia oleracea / Q000201:enzymology; D013696:Temperature; D014026:Nicotiana / Q000201:enzymology
chemical_list: D007477:Ions; D045332:Photosystem II Protein Complex; D010940:Plant Proteins; D011994:Recombinant Proteins; D010100:Oxygen