8ABB

Complex III2 from Yarrowia lipolytica, ascorbate-reduced, c-position

8ABB の概要

• エントリーDOI: 10.2210/pdb8abb/pdb
• EMDBエントリー: 15317
• 分子名称: Cytochrome b, YALI0C12210p, PROTOPORPHYRIN IX CONTAINING FE, ... (18 entities in total)
• 機能のキーワード: oxidoreductase, electron transport chain, membrane protein
• 由来する生物種: Yarrowia lipolytica; 詳細
• タンパク質・核酸の鎖数: 20
• 化学式量合計: 547313.86

構造登録者

Wieferig, J.P.,Kuhlbrandt, W. (登録日: 2022-07-04, 公開日: 2023-01-11, 最終更新日: 2023-01-25)

主引用文献

Wieferig, J.P.,Kuhlbrandt, W.
Analysis of the conformational heterogeneity of the Rieske iron-sulfur protein in complex III 2 by cryo-EM.
Iucrj, 10:27-37, 2023

PubMed Abstract: Movement of the Rieske domain of the iron-sulfur protein is essential for intramolecular electron transfer within complex III (CIII) of the respiratory chain as it bridges a gap in the cofactor chain towards the electron acceptor cytochrome c. We present cryo-EM structures of CIII from Yarrowia lipolytica at resolutions up to 2.0 Å under different conditions, with different redox states of the cofactors of the high-potential chain. All possible permutations of three primary positions were observed, indicating that the two halves of the dimeric complex act independently. Addition of the substrate analogue decylubiquinone to CIII with a reduced high-potential chain increased the occupancy of the Q site. The extent of Rieske domain interactions through hydrogen bonds to the cytochrome b and cytochrome c subunits varied depending on the redox state and substrate. In the absence of quinols, the reduced Rieske domain interacted more closely with cytochrome b and cytochrome c than in the oxidized state. Upon addition of the inhibitor antimycin A, the heterogeneity of the cd-helix and ef-loop increased, which may be indicative of a long-range effect on the Rieske domain.

PubMed: 36598500
DOI: 10.1107/S2052252522010570

実験手法

ELECTRON MICROSCOPY (3.2 Å)