在硫酸盐氧化酶的临床突变中改变了活性部位协调
Christian J Doonan1, Heather L Wilson, K V Rajagopalan
1Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
Journal of the American Chemical Society
|July 5, 2007
概括
与野生类型相比,硫酸盐氧化酶突变酶显示出不同的活性位结构. 这种涉及谷氨胺协调的结构变化解释了突变者的改变性质.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 计算化学计算化学
背景情况:
- 硫酸盐氧化酶是人类生理学的重要酶.
- 临床突变可以改变酶的结构和功能.
- 氨酸160 --> 谷氨酸突变会影响硫酸盐氧化酶的活性.
研究的目的:
- 为了研究阿尔金氨-160 --> 胺硫酸盐氧化酶突变的活性部位的结构变化.
- 了解这些结构变化如何与突变酶的特性有关.
主要方法:
- 用X射线吸收光谱 (XAS) 探测部位.
- 密度函数理论 (DFT) 计算用于结构和电子分析.
主要成果:
- 突变酶表现出一个六坐标的,伪八面体活性位.
- 谷氨胺的Oepsilon原子坐标与突变物中的中心有关.
- 野生类型的酶有一个五坐标的,方形的金字塔型基站点.
结论:
- 位上的协调差异解释了先前报道的阿金素160 --> 胺突变的特性.
- 对酶突变的结构洞察力对于理解生理作用至关重要.
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