時間解明の結晶学は,分子呼吸と整合したアロステリック通信を明らかにする
Pedram Mehrabi1,2,3, Eike C Schulz1, Raison Dsouza1,4
1Department for Atomically Resolved Dynamics, Max-Planck-Institute for Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany.
Science (New York, N.Y.)
|September 14, 2019
まとめ
研究者は,触媒処理中の酵素フッ素酸脱塩酵素の動態を視覚化しました. 分子呼吸を含む 繰り返し起こるタンパク質の構造の変化は 触媒機構の鍵です
科学分野:
- 生化学と構造生物学
- 酵素学
- タンパク質ダイナミクス
背景:
- 酵素の機能を理解するには タンパク質の構造と動的変化を 結びつける必要があります
- フッ素酸脱塩酵素は,代謝プロセスに不可欠な酵素です.
- 高解像度で酵素触媒を視覚化することは依然として困難です.
研究 の 目的:
- 催化サイクル中のフッ素酸脱塩酵素の動的構造変化を視覚化する.
- 分子呼吸の動きと 酵素の活性を相関させるため
- タンパク質のダイナミクスとエントロピーの役割を理解する.
主な方法:
- 急速な構造変化を捉えるために時間解像度の連続シンクロトロン結晶学を使用した.
- 30ミリ秒から30秒までの 18の時間点でデータを収集した.
- 逆戻りできない酵素反応の4つのターンオーバーサイクルを分析した.
主要な成果:
- 観察された連続的なステップ:基板結合,共価中間生成,水分子の活性化,および製品放出.
- 微妙なタンパク質の構造変化と 活力的な水分子の位置づけを 特定した
- 半部部位の反応性を視覚化し,触媒的なステップと相関する分子呼吸運動.
結論:
- 酵素触媒は,繰り返し起こるタンパク質の構造の変化による動的およびエントロピ的貢献を含みます.
- 酵素とリガンドの相互作用によって引き起こされる 分子呼吸運動は 触媒機構に不可欠です
- 時間解像度結晶学は 酵素反応のメカニズムに 前例のない洞察力を提供します
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