1Q90

Structure of the cytochrome b6f (plastohydroquinone : plastocyanin oxidoreductase) from Chlamydomonas reinhardtii

1Q90 の概要

• エントリーDOI: 10.2210/pdb1q90/pdb
• 分子名称: Apocytochrome f, HEME C, BETA-CAROTENE, ... (18 entities in total)
• 機能のキーワード: membrane protein complex, photosynthesis, electron transfer, oxydoreductase, chlorophyll, beta-carotene, stigmatellin, sulfoquinovosyldiacylglycerol, monogalactosyldiacylglycerol
• 由来する生物種: Chlamydomonas reinhardtii; 詳細
• 細胞内の位置: Plastid, chloroplast thylakoid membrane; Single-pass membrane protein: P23577 P49728 P23230 P49728 Q08362; Plastid, chloroplast thylakoid membrane; Multi-pass membrane protein: Q00471 Q42496; Plastid, chloroplast thylakoid membrane; Single-pass membrane protein (By similarity): P50369 P50369
• タンパク質・核酸の鎖数: 9
• 化学式量合計: 113863.18

構造登録者

Stroebel, D.,Choquet, Y.,Popot, J.-L.,Picot, D. (登録日: 2003-08-22, 公開日: 2003-12-09, 最終更新日: 2024-10-30)

主引用文献

Stroebel, D.,Choquet, Y.,Popot, J.-L.,Picot, D.
An Atypical Haem in the Cytochrome B6F Complex
Nature, 426:413-418, 2003

PubMed Abstract: Photosystems I and II (PSI and II) are reaction centres that capture light energy in order to drive oxygenic photosynthesis; however, they can only do so by interacting with the multisubunit cytochrome b(6)f complex. This complex receives electrons from PSII and passes them to PSI, pumping protons across the membrane and powering the Q-cycle. Unlike the mitochondrial and bacterial homologue cytochrome bc(1), cytochrome b(6)f can switch to a cyclic mode of electron transfer around PSI using an unknown pathway. Here we present the X-ray structure at 3.1 A of cytochrome b(6)f from the alga Chlamydomonas reinhardtii. The structure bears similarities to cytochrome bc(1) but also exhibits some unique features, such as binding chlorophyll, beta-carotene and an unexpected haem sharing a quinone site. This haem is atypical as it is covalently bound by one thioether linkage and has no axial amino acid ligand. This haem may be the missing link in oxygenic photosynthesis.

PubMed: 14647374
DOI: 10.1038/nature02155

実験手法

X-RAY DIFFRACTION (3.1 Å)