通过计算设计提高人工金属酶的催化性能
Tillmann Heinisch1, Michela Pellizzoni1, Marc Dürrenberger1
1†Department of Chemistry, University of Basel, 4056 Basel, Switzerland.
Journal of the American Chemical Society
|July 31, 2015
概括
计算设计优化了人工转移化酶 (ATHases),以改善非对称减排中的催化活性和酶选择性. 这种增强的酶设计导致了更高的 (S) - 沙索利丁的产量,这是一个关键的制药前体.
科学领域:
- 生物催化剂是一种生物催化剂.
- 计算化学计算化学
- 酶工程是什么? 酶工程是什么?
背景情况:
- 人工金属酶将小分子催化剂反应性与酶选择性结合在一起.
- 调整催化性能需要针对特定应用的新方法.
- 基于结构的计算设计为设计改进的酶变体提供了一条途径.
研究的目的:
- 使用罗塞塔设计,对人工转移酶 (ATHase) 进行基因优化.
- 为了增强催化活性和对不对称的imine减少的enantioselectivity.
- 为了研究蛋白质突变和催化剂修改对ATHase性能的影响.
主要方法:
- 罗塞塔设计的应用基于晶体结构的蛋白质工程.
- 产生具有稳定性和疏水性突变的hCAII变体.
- 丹西胺竞争测试以确定催化剂-蛋白质亲和力.
- 一个循环的imine前体的非对称的减少salsolidine.
- 对催化剂的Cp*-moiety进行修改,以增加疏水性.
主要成果:
- 四种hCAII变体对复合物的亲和力提高了46-64倍.
- 对于 (S) - 萨尔索利丁生产的酶选择活性从70% ee增加到高达92% ee.
- 总营业额增加了4倍.
- 用替代剂修饰的催化剂达到96% ee,这是该ATHase的最高可选性.
- 射线晶体学证实了在蛋白质结构中嵌入辅因子.
结论:
- 基于结构的计算设计成功优化了ATHase的性能.
- 工程ATHases表现出显著增强的活性和酶选择性.
- 催化剂修改与蛋白质工程结合,进一步提高了立体选择性.
- 该研究提供了一种经过验证的计算方法,用于设计高度选择性的人工金属酶.
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