メソフィル性およびハイパー・サーモフィル性ダイヒドロフォラート還元酶における異なるダイナミック効果
Louis Y P Luk1, E Joel Loveridge, Rudolf K Allemann
1School of Chemistry, Cardiff University , Main Building, Park Place, Cardiff CF10 3AT, United Kingdom.
Journal of the American Chemical Society
|May 1, 2014
まとめ
タンパク質のダイナミクスは,Thermotogaの海洋二水酸化葉酸還元酵素 (TmDHFR) の触媒に影響を与えない. 他の酵素とは異なり,TmDHFRFRは
科学分野:
- バイオケミストリー バイオケミストリー
- 酵素学 酵素学とは
- タンパク質のダイナミクス
背景:
- ディヒドロフォラート還元酵素 (DHFR) は細胞代謝に不可欠です.
- タンパク質のダイナミクスは,酵素触媒に影響することが知られている.
- E. coli DHFR (EcDHFR) に関する以前の研究では,タンパク質の運動と反応速度との結合が示されました.
研究 の 目的:
- Thermotoga maritima DHFR (TmDHFR) の触媒メカニズムにおけるタンパク質ダイナミクスの役割を調査する.
- ダイナミックカップリングがTmDHFRにおけるヒドリド移転に影響するかどうかを判断する.
主な方法:
- (15) N, (13) C, (2) Hを用いた酵素同位体置換.
- TmDHFRにおけるヒドリド移転ステップの運動分析.
主要な成果:
- 同位体置換は,TmDHFRにおけるヒドリド移転の速度常数に影響を与えなかった.
- これは,同位体置換が反応性を低下させたECDHFRの発見と対照的である.
- TmDHFRは,EcDHFRで観察されたダイナミックカップリングが欠如しているようです.
結論:
- タンパク質の動きと反応座標のダイナミックな結合は,すべての酵素触媒に不可欠ではない.
- 酵素触媒の効率は,タンパク質のダイナミクスに普遍的に依存しているわけではない.
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