酸素 fotosynthesisのサイトクロームb6f複合体の構造: 穴のチューニング

Genji Kurisu¹, Huamin Zhang, Janet L Smith

¹Department of Biological Sciences, 915 West State Street, Purdue University, West Lafayette, IN 47907-2054, USA.

Science (New York, N.Y.)

|October 4, 2003

まとめ

サイトクロームb6f複合体は

科学分野:

バイオケミストリーバイオケミストリー
光合成の研究研究である.
構造生物学構造生物学とは

背景:

細胞染色体b6f複合体は,酸素 fotosynthesisに不可欠であり,光システムIとIIをリンクします.
それはアデノシン三リン酸 (ATP) の合成に不可欠な陽子梯度を生成します.

研究の目的:

Mastigocladus laminosusから得られた二次性サイトクロームb6f複合体の結晶構造を決定する.
光合成におけるその機能の構造的基礎を解明する.

主な方法:

3.0アングストームの解像度のX線結晶学.
二次元複合体の構造分析. 二次元複合体の構造分析.

主要な成果:

二次元のb6f複合体の詳細な3.0アングストームの結晶構造が得られた.
大きな,脂質安定化キノン交換腔が特定され,プラストキノン,阻害剤,および新しいヘムと結合しました.
構造は,呼吸器細胞染色体bc1複合体との類似性を明らかにしますが,ドメインの配置と義肢群の有意な違いがあります.

結論:

結晶構造は,シトクロームb6f複合体のメカニズムについての洞察を提供します.
ドメインの配置と義肢群の違いは,呼吸器複合体と比較して異なる機能的役割を示唆しています.
リスケ鉄硫黄タンパク質の外在ドメインの動きは,光合成におけるその役割に適応している可能性が高い.

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