7FIX

Cryo-EM structure of cyanobacterial photosystem I in the presence of ferredoxin and cytochrome c6

これはPDB形式変換不可エントリーです。

7FIX の概要

• エントリーDOI: 10.2210/pdb7fix/pdb
• EMDBエントリー: 31605
• 分子名称: Photosystem I P700 chlorophyll a apoprotein A1, Photosystem I reaction center subunit XI, Photosystem I reaction center subunit XII, ... (24 entities in total)
• 機能のキーワード: photosystem i, ferredoxin, cytochrome c6, photosynthesis
• 由来する生物種: Thermosynechococcus vestitus BP-1; 詳細
• タンパク質・核酸の鎖数: 39
• 化学式量合計: 1125795.17

構造登録者

Li, J.,Kurisu, G. (登録日: 2021-08-01, 公開日: 2022-09-21, 最終更新日: 2022-09-28)

主引用文献

Li, J.,Hamaoka, N.,Makino, F.,Kawamoto, A.,Lin, Y.,Rogner, M.,Nowaczyk, M.M.,Lee, Y.H.,Namba, K.,Gerle, C.,Kurisu, G.
Structure of cyanobacterial photosystem I complexed with ferredoxin at 1.97 angstrom resolution.
Commun Biol, 5:951-951, 2022

PubMed Abstract: Photosystem I (PSI) is a light driven electron pump transferring electrons from Cytochrome c (Cyt c) to Ferredoxin (Fd). An understanding of this electron transfer process is hampered by a paucity of structural detail concerning PSI:Fd interface and the possible binding sites of Cyt c. Here we describe the high resolution cryo-EM structure of Thermosynechococcus elongatus BP-1 PSI in complex with Fd and a loosely bound Cyt c. Side chain interactions at the PSI:Fd interface including bridging water molecules are visualized in detail. The structure explains the properties of mutants of PsaE and PsaC that affect kinetics of Fd binding and suggests a molecular switch for the dissociation of Fd upon reduction. Calorimetry-based thermodynamic analyses confirms a single binding site for Fd and demonstrates that PSI:Fd complexation is purely driven by entropy. A possible reaction cycle for the efficient transfer of electrons from Cyt c to Fd via PSI is proposed.

PubMed: 36097054
DOI: 10.1038/s42003-022-03926-4

実験手法

ELECTRON MICROSCOPY (1.97 Å)