果糖-1,6-双酸盐阿尔多酶/酸酶的双功能性的结构基础
Shinya Fushinobu1, Hiroshi Nishimasu, Daiki Hattori
1Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
Nature
|October 11, 2011
概括
古代果糖-1,6-双酸盐 (FBP) 酶/酸酶 (FBPA/P) 独特地利用单个活性位点催化两个不同的反应. 结构分析揭示了动态活性部位的变化,使这种双重酶功能成为可能.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 结构生物学 结构生物学
背景情况:
- 酶通常催化一种特定的生物化学反应.
- 双功能酶通常具有明显的催化域或杂乱的活性位点.
- 古代果糖-1,6-双酸盐 (FBP) 酸盐/酸酶 (FBPA/P) 是一个例外,在单个域内催化了两个不同的反应.
研究的目的:
- 阐明古老FBPA/P.的双重催化活性背后的分子机制.
- 了解一个单一的酶活性部位如何可以执行两个化学上不同的反应.
主要方法:
- 进行X射线晶体学以确定FBPA/P以其阿尔多酶形式的1.5-Å分辨率结构.
- 酶的阿尔多酶和先前确定的酸酶形式之间的结构比较.
主要成果:
- 晶体结构揭示了关键的氨酸残留物,形成了与酸 (DHAP) 在阿尔多酶形式的希夫基.
- 在比较阿尔多酶和酸酶形式时,观察到活性部位的显著构造变化.
- FBPA/P 动态地改变其活跃站点架构,以适应其双重催化功能.
结论:
- 考古FBPA/P通过活性部位的变形表现出一种新的双功能机制.
- 这一发现挑战了传统的理解,即一个酶活性部位对单个生物化学反应负责.
- 这项研究扩大了已知的酶催化策略的范围.
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