英国曼彻斯特大学Jason Micklefield课题组在研究中取得进展。他们实现了酰胺合成连接酶的发现、表征和工程化。 相关论文于2021年5月19日发表于国际顶尖学术期刊《自然》杂志上。
该课题组描述了一个酶家族，冠菌酸连接酶(CfaLs)，并解析了它们的结构。该研究组发现CfaL也可以产生JA-Ile，尽管与负责在植物中连接JA和L-Ile的Jar1酶的相似性较低。这表明Jar1和CfaL可独立进化以催化相似的反应——Jar1产生植物发育必不可少的化合物同时细菌连接酶产生对植物有毒的类似物。
该课题组进一步证明了如何使用CfaL酶来合成各种酰胺，从而消除了对保护基的需求。研究人员实现了高选择性的外消旋给体或受体底物的动力学拆分，提供了同手性产物。
课题组人员还利用基于结构的诱变来工程化优化的CfaL变体。总之，这些结果表明，CfaLs可以提供广泛的酰胺农药、医药和其他应用。
据了解，冠菌素（Coronatine）和相关的细菌植物毒素是茉莉酰-L-异亮氨酸(JA-Ile)的类似物，它介导重要的生理植物信号通路。类冠菌素的植物毒素破坏了这些基本途径，在开发更安全、更具选择性的除草剂方面具有潜力。虽然之前已经对冠菌素的生物合成进行了研究，但催化冠菌酸与氨基酸关键偶联的酶的性质仍然未知。
附：英文原文
Title: Discovery, characterization and engineering of ligases for amide synthesis
Author: Michael Winn, Michael Rowlinson, Fanghua Wang, Luis Bering, Daniel Francis, Colin Levy, Jason Micklefield
Issue&Volume: 2021-05-19
Abstract: Coronatine and related bacterial phytotoxins are mimics of the hormone jasmonyl-L-isoleucine (JA-Ile), which mediates physiologically important plant signalling pathways1,2,3,4. Coronatine-like phytotoxins disrupt these essential pathways and have potential in the development of safer, more selective herbicides. Although the biosynthesis of coronatine has been investigated previously, the nature of the enzyme that catalyses the crucial coupling of coronafacic acid to amino acids remains unknown1,2. Here we characterize a family of enzymes, coronafacic acid ligases (CfaLs), and resolve their structures. We found that CfaL can also produce JA-Ile, despite low similarity with the Jar1 enzyme that is responsible for ligation of JA and L-Ile in plants5. This suggests that Jar1 and CfaL evolved independently to catalyse similar reactions—Jar1 producing a compound essential for plant development4,5, and the bacterial ligases producing analogues toxic to plants. We further demonstrate how CfaL enzymes can be used to synthesize a diverse array of amides, obviating the need for protecting groups. Highly selective kinetic resolutions of racemic donor or acceptor substrates were achieved, affording homochiral products. We also used structure-guided mutagenesis to engineer improved CfaL variants. Together, these results show that CfaLs can deliver a wide range of amides for agrochemical, pharmaceutical and other applications.
DOI: 10.1038/s41586-021-03447-w
Source: https://www.nature.com/articles/s41586-021-03447-w