7ZYV

Cryo-EM structure of catalytically active Spinacia oleracea cytochrome b6f in complex with endogenous plastoquinones at 2.13 A resolution

7ZYV の概要

• エントリーDOI: 10.2210/pdb7zyv/pdb
• EMDBエントリー: 14123 15027
• 分子名称: Cytochrome b6, PROTOPORPHYRIN IX CONTAINING FE, HEME C, ... (17 entities in total)
• 機能のキーワード: cytochrome, spinacia oleracea, plastoquinones, cryo-em, photosynthesis
• 由来する生物種: Spinacia oleracea (spinach); 詳細
• タンパク質・核酸の鎖数: 18
• 化学式量合計: 290610.70

構造登録者

Sarewicz, M.,Szwalec, M.,Pintscher, S.,Indyka, P.,Rawski, M.,Pietras, R.,Mielecki, B.,Koziej, L.,Jaciuk, M.,Glatt, S.,Osyczka, A. (登録日: 2022-05-25, 公開日: 2023-01-25, 最終更新日: 2025-10-01)

主引用文献

Sarewicz, M.,Szwalec, M.,Pintscher, S.,Indyka, P.,Rawski, M.,Pietras, R.,Mielecki, B.,Koziej, L.,Jaciuk, M.,Glatt, S.,Osyczka, A.
High-resolution cryo-EM structures of plant cytochrome b 6 f at work.
Sci Adv, 9:eadd9688-eadd9688, 2023

PubMed Abstract: Plants use solar energy to power cellular metabolism. The oxidation of plastoquinol and reduction of plastocyanin by cytochrome bf (Cyt bf) is known as one of the key steps of photosynthesis, but the catalytic mechanism in the plastoquinone oxidation site (Q) remains elusive. Here, we describe two high-resolution cryo-EM structures of the spinach Cyt bf homodimer with endogenous plastoquinones and in complex with plastocyanin. Three plastoquinones are visible and line up one after another head to tail near Q in both monomers, indicating the existence of a channel in each monomer. Therefore, quinones appear to flow through Cyt bf in one direction, transiently exposing the redox-active ring of quinone during catalysis. Our work proposes an unprecedented one-way traffic model that explains efficient quinol oxidation during photosynthesis and respiration.

PubMed: 36638176
DOI: 10.1126/sciadv.add9688

実験手法

ELECTRON MICROSCOPY (2.13 Å)