Dobrijevic Dragana, Benhamou Laure, Aliev Abil E, Méndez-Sánchez Daniel, Dawson Natalie, Baud Damien, Tappertzhofen Nadine, Moody Thomas S, Orengo Christine A, Hailes Helen C, Ward John M
Department of Biochemical Engineering, University College London Bernard Katz Building London WC1H 6BT UK
Department of Chemistry, University College London 20 Gordon Street London WC1H 0AJ UK
RSC Adv. 2019 Nov 11;9(63):36608-36614. doi: 10.1039/c9ra06088j.
Ene-reductases (ERs) of the Old Yellow Enzyme family catalyse asymmetric reduction of activated alkenes providing chiral products. They have become an important method in the synthetic chemists' toolbox offering a sustainable alternative to metal-catalysed asymmetric reduction. Development of new biocatalytic alkene reduction routes, however needs easy access to novel biocatalysts. A sequence-based functional metagenomic approach was used to identify novel ERs from a drain metagenome. From the ten putative ER enzymes initially identified, eight exhibited activities towards widely accepted mono-cyclic substrates with several of the ERs giving high reaction yields and stereoselectivities. Two highly performing enzymes that displayed excellent co-solvent tolerance were used for the stereoselective reduction of sterically challenging bicyclic enones where the reactions proceeded in high yields, which is unprecedented to date with wild-type ERs. On a preparative enzymatic scale, reductions of Hajos-Parish, Wieland-Miescher derivatives and a tricyclic ketone proceeded with good to excellent yields.
老黄色酶家族的烯还原酶（ERs）催化活化烯烃的不对称还原反应，生成手性产物。它们已成为合成化学家工具库中的一种重要方法，为金属催化的不对称还原反应提供了一种可持续的替代方案。然而，开发新的生物催化烯烃还原路线需要能够方便地获得新型生物催化剂。基于序列的功能宏基因组学方法被用于从下水道宏基因组中鉴定新型ERs。从最初鉴定出的10种假定的ER酶中，有8种对广泛接受的单环底物表现出活性，其中几种ER酶具有较高的反应产率和立体选择性。两种表现优异且对共溶剂耐受性良好的酶被用于空间位阻较大的双环烯酮的立体选择性还原反应，反应产率很高，这在野生型ERs中是前所未有的。在制备酶规模上，哈约什-帕里什、维兰德-米舍尔衍生物和一种三环酮的还原反应产率良好至优异。
