溶解による触媒:SAMに依存したハリドアルキル化酵素の触媒能力
Danielle C Lohman1, David R Edwards, Richard Wolfenden
1Department of Biochemistry and Biophysics, School of Medicine, University of North Carolina , Chapel Hill, North Carolina 27599, United States.
Journal of the American Chemical Society
|September 18, 2013
まとめ
酵素は,S-アデノシルメチオニンからアルキル基を移転することによって,生物学的ハリドイオン固定を触媒化する. これらの酵素はアルキルハリドの形成を著しく加速し,コファクターや金属イオンなしで顕著な速度向上を示しています.
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
- ハリドイオン代謝について
背景:
- 生物学的ハリドイオン固定には,S-アデノシルメチオニンから酵素によるアルキル転送が含まれます.
- いくつかの酵素が,このアルキル転移反応を触媒として作用することが知られている.
研究 の 目的:
- トリメチルスルフォニウムイオンの様々なハリドイオンと水との反応速度を測定する.
- これらの速度をフッ素酵素と塩素酵素の酵素触媒と比較する.
主な方法:
- I, Br, Cl, F, HO, H2Oとのトリメチルスルフォニウムイオンの反応の運動分析.
- 酵素データとの比較のために,二次速度常数の25 °Cへのエクストラポレーション.
主要な成果:
- トリメチルスルフォニウムイオン反応の第2次速度定数を決定した.
- 酵素フッ素酵素と塩素酵素は,アルキルハリドの形成速度をそれぞれ2×10−15倍と1×10−17倍に増加させる.
- これらの速度の向上は,2基板酵素で報告された最大のものです.
結論:
- 酵素触媒は,アルキルハリド形成の速度を大幅に向上させます.
- フッ素酵素と塩素酵素は,共因子,金属イオン,または一般的な酸塩触媒なしで,著しい速度加速を達成します.
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