奇拉酸盐,酸盐和酸盐的分辨率由一个enantioselective酶库的分辨率
Charity Nowlan1, Yingchun Li, Johannes C Hermann
1Department of Chemistry, Texas A&M University, College Station, Texas 77842-3012, USA.
Journal of the American Chemical Society
|December 7, 2006
概括
细菌的三酶酶可以被设计成可以选择性地分解的酸盐,酸盐和酸盐. 突变极大地改变了酶的选择性,使各种化学化合物的动力分解成为可能.
科学领域:
- 生物化学和酶学 生物化学和酶学
- 蛋白质工程是指蛋白质工程.
- 有机化学 有机化学
背景情况:
- 细菌三酶 (PTE) 是一种金属酶,以化有机化合物而闻名.
- 了解PTE的立体选择性歧视对于开发反选择性催化剂至关重要.
- 化酸盐,酸盐和酸盐作为探测酶活性位点的有价值的基质.
研究的目的:
- 调查野生型和突变的细菌三酶酶对立体选择性歧视的范围.
- 为了工程改造的PTE酶与改变的enantioselective特性的动力分辨率.
- 探索活性部位结构,基质结合和催化活性之间的关系.
主要方法:
- 合成并测试了16种化酸盐,酸盐和酸盐的16个反体对.
- 使用特定位点的突变产生15个突变的PTE酶.
- 利用过渡状态类型的计算对接来建模酶基质相互作用.
主要成果:
- 野生类型的PTE表现出高的酶选择性水解率,从3到5.4×10^5.5不等.
- 单位突变G60A增加了1-3个数量级的立体选择性.
- 突变者I106G/F132G/H257Y反向立体选择性,在突变者之间实现了3.6×10^8的歧视.
结论:
- 细菌三酶活性部位非常容易通过氨基酸替代进行结构修饰.
- 工程 PTE 变种可以实现显著的 enantioselective 歧视,使不同的动力分辨率.
- 计算建模支持这样一个假设,即非生产性结合和过渡状态稳定性控制了对抗选择性.
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