F1-ATPaseのミリ秒未満の運動分析により,異なる回転サブステップの解像度

R Yasuda¹, H Noji, M Yoshida

¹CREST 'Genetic Programming' Team 13, Teikyo University Biotechnology Center 3F, Nogawa 907, Miyamae-Ku, Kawasaki 216-0001, Japan.

Nature

|April 20, 2001

まとめ

F1-ATPaseという酵素です.

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.
酵素学酵素学とは

背景:

F1-ATPaseは,中央のガンマ亜単位がアルファ3ベータ3亜単位の中で回転する回転モーターとして機能します.
酵素の段階的な回転は,連続的なATP水解に関連していますが,ステップメカニズムは不明です.

研究の目的:

低ATP濃度でのF1-ATPaseのステップアップのメカニズムを解明する.
酵素の回転運動に関与するサブステップを特徴付けるために.

主な方法:

酵素の回転を観察するために高速画像技術を使用した.
副ステップのタイミングとドライバーを決定するために,運動分析が行われました.

主要な成果:

F1-ATPaseの回転の120度ステップは,90度と30度の分ステップで構成されています.
ATP結合が90度次段を始動し,製品放出が30度次段を推し進める可能性がある.
これらのサブステップは,約1ミリ秒の反応相で隔てられており,ATP水解サイクルを支配しています.

結論:

特定されたサブステップメカニズムは,幅広い範囲のATP濃度におけるF1-ATPaseの回転を説明する.
この詳細なメカニズムは,F1-ATPaseの逆回転によるATP合成の結合変化モデルをサポートしています.

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