5MDX

Cryo-EM structure of the PSII supercomplex from Arabidopsis thaliana

5MDX の概要

• エントリーDOI: 10.2210/pdb5mdx/pdb
• EMDBエントリー: 3491
• 分子名称: Photosystem II protein D1, Photosystem II reaction center protein L, Photosystem II reaction center protein M, ... (25 entities in total)
• 機能のキーワード: photosynthesis, photosystem ii supercomplex, single particle analysis
• 由来する生物種: Arabidopsis thaliana (Mouse-ear cress); 詳細
• タンパク質・核酸の鎖数: 50
• 化学式量合計: 1272946.91

構造登録者

van Bezouwen, L.S.,Caffarri, S.,Kale, R.S.,Kouril, R.,Thunnissen, A.M.W.H.,Oostergetel, G.T.,Boekema, E.J. (登録日: 2016-11-13, 公開日: 2017-06-21, 最終更新日: 2019-04-24)

主引用文献

van Bezouwen, L.S.,Caffarri, S.,Kale, R.S.,Kouril, R.,Thunnissen, A.W.H.,Oostergetel, G.T.,Boekema, E.J.
Subunit and chlorophyll organization of the plant photosystem II supercomplex.
Nat Plants, 3:17080-17080, 2017

PubMed Abstract: Photosystem II (PSII) is a light-driven protein, involved in the primary reactions of photosynthesis. In plant photosynthetic membranes PSII forms large multisubunit supercomplexes, containing a dimeric core and up to four light-harvesting complexes (LHCs), which act as antenna proteins. Here we solved a three-dimensional (3D) structure of the CSM supercomplex from Arabidopsis thaliana using cryo-transmission electron microscopy (cryo-EM) and single-particle analysis at an overall resolution of 5.3 Å. Using a combination of homology modelling and restrained refinement against the cryo-EM map, it was possible to model atomic structures for all antenna complexes and almost all core subunits. We located all 35 chlorophylls of the core region based on the cyanobacterial PSII structure, whose positioning is highly conserved, as well as all the chlorophylls of the LHCII S and M trimers. A total of 13 and 9 chlorophylls were identified in CP26 and CP24, respectively. Energy flow from LHC complexes to the PSII reaction centre is proposed to follow preferential pathways: CP26 and CP29 directly transfer to the core using several routes for efficient transfer; the S trimer is directly connected to CP43 and the M trimer can efficiently transfer energy to the core through CP29 and the S trimer.

PubMed: 28604725
DOI: 10.1038/nplants.2017.80

実験手法

ELECTRON MICROSCOPY (5.3 Å)