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I know what you're thinking: "Autumn is here!Who needs sunny weather and optimism?Sign me up for grey skies and vitamin D supplements!".哦，你没想到？我也一样。Well perhaps Halloween gives you more joy,除了有机会看到你的一个同事穿得像弗雷迪·墨丘利（Freddy Mercury），胸部印有“Hg”字样，经典)部门聚会吗?

In the spirit of Halloween,Simone Morra and Anca Pordea at the University of Nottingham have synthesized a mutant alcohol dehydrogenase enzyme turned Frankenstein catalyst,by replacing the zinc catalytic site with a covalently-bound rhodium(III) complex.所得到的突变/过渡金属复合物与野生型酶结合用于合成手性醇。（S)-4-phenyl-2-butanol.

Like many hybrid systems,the purpose of combining enzymatic with transition metal catalysis is to take advantage of the benefits of each.数百万年的进化已经产生了在温和条件下起作用的酶催化剂，在水溶剂中，with impressive selectivity and high catalytic efficiency.但酶在较窄范围内的作用在合成环境中可能是不利的。另一方面，transition metal catalysts are versatile and can be easily customised,与自由反应，使最混乱的酶脸红。

不幸的是，开发利用过渡金属和酶催化的多组分系统并不像将它们组合成单一混合物那么简单，as mutual deactivation often results.作者发现，将过渡金属复合物包裹在酶中提供了一种物理屏蔽，以防抑制。and preserved the activity of both the wild type enzyme and the rhodium(III) complex.

两个相互连接的催化循环负责手性醇的合成。In the first,the wild type enzyme effected reduction of 4-phenyl-2-butanol,一种依赖于生物还原剂烟酰胺腺嘌呤二核苷酸磷酸（NADPH）的过程。In the second cycle,使用复合铑（III）复合物/突变体酶回收NADPH，以甲酸为化学计量还原剂。The rate of alcohol formation was slow (turnover frequency of 0.02 s^{- 1}）过渡金属催化过程被认为是速率限制（与4.8 s的转换频率相比^{- 1}for enzymatic systems).However,near perfect enantioselectivity was obtained (>99%EE).

这项研究表明，过渡金属催化剂可以扩大共因子依赖酶的范围。此外，设计制备金属复合物/酶生物结合物的策略可能对小分子合成有价值，因为酶提供了第二个配位域；包封立体环境是提高催化反应选择性的有效途径。

要了解更多信息，请阅读：

Biocatalyst-artifical metalloenzyme cascade based on alcohol dehydrogenase

Simone Morra安卡波尔德亚
化学。脊髓损伤.,2018,九，7447-7454
DOI:10.1039/c8sc02371a

关于作者

Zo_Hearne是蒙特利尔麦吉尔大学化学博士生，新利手机客户端加拿大在李超教授的监督下。她来自堪培拉，Australia,where she completed her undergraduate degree.她目前的研究重点是过渡金属催化，以实现新的转变，and out of the lab she is an enthusiastic 新利手机客户端chemistry tut新利手机客户端or and science communicator.