title: Structural insights into energy regulation of light-harvesting complex CP29 from spinach.
abstract: CP29, one of the minor light-harvesting complexes of higher-plant photosystem II, absorbs and transfers solar energy for photosynthesis and also has important roles in photoprotection. We have solved the crystal structure of spinach CP29 at 2.80-Å resolution. Each CP29 monomer contains 13 chlorophyll and 3 carotenoid molecules, which differs considerably from the major light-harvesting complex LHCII and the previously proposed CP29 model. The 13 chlorophyll-binding sites are assigned as eight chlorophyll a sites, four chlorophyll b and one putative mixed site occupied by both chlorophylls a and b. Based on the present X-ray structure, an integrated pigment network in CP29 is constructed. Two special clusters of pigment molecules, namely a615-a611-a612-Lut and Vio(Zea)-a603-a609, have been identified and might function as potential energy-quenching centers and as the exit or entrance in energy-transfer pathways.
authors.affiliation: National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Pan
authors.forename: Mei
authors.initials: M
authors.lastname: Li
authors.forename: Tao
authors.initials: T
authors.lastname: Wan
authors.forename: Longfei
authors.initials: L
authors.lastname: Wang
authors.forename: Chenjun
authors.initials: C
authors.lastname: Jia
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Hou
authors.forename: Xuelin
authors.initials: X
authors.lastname: Zhao
authors.forename: Jiping
authors.initials: J
authors.lastname: Zhang
authors.forename: Wenrui
authors.initials: W
authors.lastname: Chang
mesh_terms: D018360:Crystallography, X-Ray; D004735:Energy Transfer; D045342:Light-Harvesting Protein Complexes / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D045332:Photosystem II Protein Complex / Q000737:chemistry* / Q000378:metabolism; D010940:Plant Proteins / Q000737:chemistry* / Q000378:metabolism; D011487:Protein Conformation; D018724:Spinacia oleracea / Q000737:chemistry* / Q000378:metabolism
chemical_list: C069660:CP29 light harvesting complex; D045342:Light-Harvesting Protein Complexes; D045332:Photosystem II Protein Complex; D010940:Plant Proteins