一种设计用于反选择性 [2+2] 循环添加的光酶
Jonathan S Trimble1,2, Rebecca Crawshaw1,2, Florence J Hardy1,2
1Department of Chemistry, The University of Manchester, Manchester, UK.
Nature
|September 21, 2022
概括
研究人员使用基因代码扩展进行三重能量转移 (EnT) 催化,设计了一种新型光酶. 这一突破使得在温和条件下有效和反选择性 [2+2] 循环添加的新蛋白功能成为可能.
科学领域:
- 生物催化和合成化学
- 蛋白质工程和生物技术
背景情况:
- 基因代码的扩展允许为新型蛋白质功能引入非正规的氨基酸.
- 三重能量转移 (EnT) 催化是一种强大的合成工具,目前无法通过生物催化.
研究的目的:
- 开发一种能够进行三重能量转移 (EnT) 催化的光酶.
- 使用蛋白质支架设计一个高效的,选择性的光催化剂.
主要方法:
- 使用遗传密码扩展来安装光敏剂到一个新的Diels-Alderase (DA_20_00).
- 使用定向进化平台来优化光酶以提高催化活性和选择性.
- 确定光酶产物复合物的X射线晶体结构.
主要成果:
- 通过EnT催化产生了一种光酶 (EnT1.0) 进行 [2+2] 循环添加.
- 开发出一种进化变体 (EnT1.3),达到高达99%的反体过量. 对于各种循环添加剂.
- 经过300次转换,有氧稳定性和环境温度运行,性能优于小分子催化剂.
- 结构分析显示蛋白质活性部位内的协同作用.
结论:
- 建立了一个基于工程蛋白质的新一代反选择性光催化剂的框架.
- 开辟了蛋白质活性位点内的激发状态化学的新可能性.
- 证明光酶具有挑战性合成转换的潜力.
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