在美索菲尔和超热索菲尔二水叶酸还原酶中的不同动态效应
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
概括
蛋白质动态没有影响Thermotoga海上二叶酸减少酶 (TmDHFR) 催化. 与其他酶不同的是,TmDHFRFR.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 蛋白质动力学 蛋白质动力学
背景情况:
- 二叶酸减少酶 (DHFR) 对于细胞代谢至关重要.
- 已知蛋白质动力学会影响酶催化.
- 以前对大肠杆菌DHFR (EcDHFR) 的研究表明,蛋白质运动和反应速率之间存在联系.
研究的目的:
- 研究蛋白质动态在Thermotoga海洋DHFR (TmDHFR) 催化机制中的作用.
- 为了确定动态合是否会影响TmDHFR中的化物转移.
主要方法:
- 使用 (15) N, (13) C 和 (2) H 的酶同位素替代.
- 在TmDHFR中对化物转移步骤的动态分析.
主要成果:
- 同位素置换没有影响TmDHFR中化物转移的速率常数.
- 这与ECDHFR的发现形成鲜明对比,在这种情况下,同位素置换降低了反应性.
- 在TmDHFR中,似乎缺乏在EcDHFR中观察到的动态合.
结论:
- 蛋白质运动与反应坐标的动态合并不是所有酶催化剂都必不可少的.
- 酶催化剂的效率并不总是取决于蛋白质动态.
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