一种酶性阿尔德反应
Masao Ohashi1, Cooper S Jamieson2, Yujuan Cai3
1Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, CA, USA.
Nature
|October 1, 2020
概括
研究人员发现了一种叫做环环酶的新酶, 这些酶控制反应结果,为生物催化提供了洞察力,并使新型催化剂的设计成为可能.
科学领域:
- 生物化学
- 有机化学
- 酵素学
背景情况:
- 设计复杂分子的选择性催化剂是化学研究的一个关键挑战.
- 大自然利用酶,如循环酶,在循环反应中实现高选择性,包括循环添加.
- 了解酶选择性背后的机制,特别是围选择性,仍然很困难.
研究的目的:
- 发现和表征新型环环,催化以前未知的生物反应.
- 阐明这些酶实现高立体选择性,区域选择性和围选择性的机制.
- 通过合理设计,设计具有改变催化功能的循环.
主要方法:
- 发现和描述两个同类的环环酶组.
- 在体外生化测试以确定酶活性和选择性.
- 计算研究以合理化观察到的反应性和指导酶工程.
- 进行X射线晶体学以获得酶共晶体结构.
- 局部定向突变生成以创建和测试酶变体
主要成果:
- 鉴定催化阿尔德烯反应 (生物学的新发现) 和立体选择性异构-迪尔斯-阿尔德反应的环环酶.
- 使用计算和结构数据在几乎相同的活跃站点中对不同反应性和选择性的合理化.
- 具有反向选活性的工程环环的演示 (Alder-ene到hetero-Diels-Alder,反之亦然).
结论:
- 周环酶可以催化各种周环反应,包括阿尔德反应,扩大已知的酶催化范围.
- 酶活性位点架构要求高区域选择性和围选择性,为催化剂设计提供了一个模型.
- 酶工程可以预测地改变催化功能和选择性,为新型生物催化剂开发铺平道路.
相关概念视频
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