基于基质的同位素酶的整体调节
Pedram Mehrabi1,2,3, Christopher Di Pietrantonio4, Tae Hun Kim4,5
1Department of Medical Biophysics , University of Toronto , Toronto , Ontario M5G 1L7 , Canada.
Journal of the American Chemical Society
|June 13, 2019
概括
乙酸脱酶使用酶动力学进行催化. 高基质度通过抑制动态来抑制这种酶,而特定的突变消除了抑制,但降低了催化速率,揭示了全调节的重要性.
科学领域:
- 生物化学
- 酵素学
- 结构生物学
背景情况:
- 许多酶表现出一半的位点反应性,一次只有一个活跃的位点功能.
- 乙酸脱酶是一种同质酶,利用基质结合来调节原体活性和动力学.
研究的目的:
- 在乙酸脱酶催化过程中研究互原体动态的作用.
- 阐明在高基质度下抑制的机制和囊的功能.
主要方法:
- 基于刚性的全传递理论
- 核磁共振 (NMR) 光谱学
- 功能测试
主要成果:
- 高基质度会导致第二基质结合,减弱原体间动力学和抑制催化.
- 一种突变 (K152I) 消除了第二位结合和抑制,但降低了最大的催化速率,表明了囊在催化中的作用.
- 外部口袋溶解基质,并促进其转移到活性部位,充当全管道.
结论:
- 酸乙酸脱酶的功能由基网络调节的酶动态至关重要.
- 高度的第二基质结合通过破坏这些基本动态来抑制催化.
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