ATP合成酵素における回転モーターの分子構造
D Stock1, A G Leslie, J E Walker
1Medical Research Council Dunn Human Nutrition Unit, Hills Road, Cambridge CB2 2XY, UK.
Science (New York, N.Y.)
|November 27, 1999
まとめ
アデノシントリフォスファート (ATP) 合成酵素は,エネルギー変換のために回転モーターを使用します. イーストミトコンドリアのATP合成酵素
科学分野:
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
- 構造生物学 構造生物学とは
背景:
- アデノシントリホスファート (ATP) 合成酵素は,生物学的エネルギー変換に責任を負う重要な酵素です.
- 膜に埋め込まれたF0セクターとF1ドメインで構成され,回転モーターとして機能します.
- F0セクターは,F1ドメインによるATP合成を推進するために,陽子運動力を利用します.
研究 の 目的:
- イーストミトコンドリアのATP合成酵素におけるF0セクターの構造的組織を解明する.
- cリングと中央茎のサブユニット間の相互作用を調査する.
- これらの相互作用が酵素の回転触媒に及ぼす影響を理解する.
主な方法:
- 酵母ミトコンドリアのATP合成亜複合体の電子密度マップを取得するために,X線結晶学を用いた.
- 電子密度マップの分析により,F0セクター内のcサブユニットの配置が明らかになりました.
- 詳細な構造分析は,cリングと中央茎のガンマとデルタサブユニット間のインターフェースに焦点を当てた.
主要な成果:
- 膜に埋め込まれたF0セクター内で10cサブユニットで構成されたリングが特定されました.
- 各cサブユニットは,アルファヘリコプター型のヘアピン形状を採用しています.
- 6~7つのcサブユニットと中央茎のガンマとデルタサブユニットとの間には,広範な接触が観察されました.
結論:
- イーストミトコンドリアのATP合成酵素の構造は,10サブユニットのc環を明らかにする.
- c環と中央茎の間の広範囲なインターフェースは,ATP合成中に調整された回転を示唆しています.
- この構造的洞察は,ATP合成酵素による生物学的エネルギー変換のメカニズムを理解するための基礎を提供します.
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