在由二甲基利三酸合成酶催化反应中的一个应对重排?
Louis Y P Luk1, Qi Qian, Martin E Tanner
1Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada.
Journal of the American Chemical Society
|July 20, 2011
概括
双甲基利利托合成酶通常在C-4的位置上对托进行先化. 然而,一个Lys174Ala突变产生的反化化物,表明一种新的生物合成途径.
科学领域:
- 生物化学 生物化学
- 有机化学 有机化学
- 酶学 是一种酶学.
背景情况:
- 藻化物是自然产品的一个重要类别.
- 甲基烯酸合成酶 (DMATS) 是藻类类生物合成中的一个关键酶.
- 该酶通常在托的C-4位置催化前化.
研究的目的:
- 为了研究二甲基利利托合成酶的催化机制.
- 阐明酶突变体中改变产品形成的结构基础.
- 在化物生物合成中探索替代的前化途径.
主要方法:
- DMATS的局部定向突变发生,从而产生Lys174Ala突变体.
- 分析由突变酶合成的主要产品.
- 结构阐明了新型的六基罗英醇化物.
主要成果:
- 这种Lys174Ala突变主要产生的是一种六四罗醇化物.
- 这种产品是通过在酸盐的C-3位置进行逆化而产生的.
- 这些发现支持了一种涉及初始C-3前化的修订机制.
结论:
- 这种Lys174Ala突变改变了DMATS的区域选择性.
- 提出了一种涉及初始C-3逆化,其次是Cope重新排列的机制.
- 这项研究为prenyltransferase酶的灵活性和机制提供了新的见解.
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