Asymmetric alkene reduction by yeast old yellow enzymes and by a novel Zymomonas mobilis reductase
Asymmetric alkene reduction by yeast old yellow enzymes and by a novel Zymomonas mobilis reductase
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DOI：
10.1002/bit.21415
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发表时间：
2007-09-01
影响因子：
3.8
通讯作者：
Rosche, Bettina
中科院分区：
文献类型：
--
作者：
Mueller, Andre;Hauer, Bernhard;Rosche, Bettina
在大肠杆菌中分别表达了酵母老黄酶(OYE1、OYE2和OYE3)和运动发酵单胞菌NAD(P)H依赖的2-环己烯-1-酮还原酶(NCR)基因。所有四个重组菌株都减少了α，β-不饱和烯烃和烯酮中的碳双键，但比率和对映体特异性不同。两种可能的对映体中哪一种是主要形成的，不仅取决于酶的选择，还取决于底物：除了对α-或β-位甲基化的依赖外，本研究的数据表明，首先碳双键的E-或Z-构型(顺式或反式)，其次底物分子的其余部分在决定对映体特异性方面发挥作用。根据目前公认的黄素介导的碳双键反氢机理，本研究中的数据可以通过OYE活性中心的一些底物的反转取向来解释。
The genes encoding yeast old yellow enzymes (OYE 1, 2, and 3) and NAD(P)H-dependent 2-cyclohexen-1-one reductase from Zymomonas mobilis (NCR) were expressed separately in Escherichia coli. All four recombinant strains reduced the carbon double bond in alpha, beta-unsaturated alkenals and alkenones, however rates and enantio-specificities differed. Which of the two possible enantiomers was predominantly formed, was not only dependent on the choice of enzyme but also on the substrate: In addition to a dependency on methylation in alpha- or beta-position, the data of this study illustrate that firstly the E- or Z-configuration (cis- or trans-) of the carbon double-bond and secondly the remainder of the substrate molecule play roles in determining enantio-specificity. Based on the currently accepted mechanism of flavin mediated anti-hydrogenation of the carbon double bond, the data in this study may be explained by a flipped orientation of some of the substrates in the active center of OYE.