2FYN

Crystal Structure Analysis of the double mutant Rhodobacter Sphaeroides bc1 complex

2FYN の概要

• エントリーDOI: 10.2210/pdb2fyn/pdb
• 関連するPDBエントリー: 1l0n 1qcr 1sqx 1zrt
• 分子名称: Cytochrome b, Cytochrome c1, Ubiquinol-cytochrome c reductase iron-sulfur subunit, ... (7 entities in total)
• 機能のキーワード: transmembrane helices, functional dimer, oxidoreductase
• 由来する生物種: Rhodobacter sphaeroides; 詳細
• 細胞内の位置: Cell membrane; Multi-pass membrane protein: Q02761; Cell membrane; Single-pass membrane protein (Potential): Q02760; Cell membrane; Single-pass membrane protein: Q02762
• タンパク質・核酸の鎖数: 18
• 化学式量合計: 615897.81

構造登録者

Esser, L.,Xia, D. (登録日: 2006-02-08, 公開日: 2006-08-29, 最終更新日: 2024-10-30)

主引用文献

Esser, L.,Gong, X.,Yang, S.,Yu, L.,Yu, C.A.,Xia, D.
Surface-modulated motion switch: Capture and release of iron-sulfur protein in the cytochrome bc1 complex.
Proc.Natl.Acad.Sci.Usa, 103:13045-13050, 2006

PubMed Abstract: In the cytochrome bc(1) complex, the swivel motion of the iron-sulfur protein (ISP) between two redox sites constitutes a key component of the mechanism that achieves the separation of the two electrons in a substrate molecule at the quinol oxidation (Q(o)) site. The question remaining is how the motion of ISP is controlled so that only one electron enters the thermodynamically favorable chain via ISP. An analysis of eight structures of mitochondrial bc(1) with bound Q(o) site inhibitors revealed that the presence of inhibitors causes a bidirectional repositioning of the cd1 helix in the cytochrome b subunit. As the cd1 helix forms a major part of the ISP binding crater, any positional shift of this helix modulates the ability of cytochrome b to bind ISP. The analysis also suggests a mechanism for reversal of the ISP fixation when the shape complementarity is significantly reduced after a positional reorientation of the reaction product quinone. The importance of shape complementarity in this mechanism was confirmed by functional studies of bc(1) mutants and by a structure determination of the bacterial form of bc(1). A mechanism for the high fidelity of the bifurcated electron transfer is proposed.

PubMed: 16924113
DOI: 10.1073/pnas.0601149103

実験手法

X-RAY DIFFRACTION (3.2 Å)