Extended Reaction Scope of Thiamine Diphosphate Dependent Cyclohexane-1,2-dione Hydrolase: From CC Bond Cleavage to CC Bond Ligation
作者:Sabrina Loschonsky、Tobias Wacker、Simon Waltzer、Pier Paolo Giovannini、Michael J. McLeish、Susana L. A. Andrade、Michael Müller
DOI:10.1002/anie.201408287
日期:2014.12.22
2‐dione hydrolase (CDH) catalyzes the CC bond cleavage of cyclohexane‐1,2‐dione to 6‐oxohexanoate, and the asymmetric benzoin condensation between benzaldehyde and pyruvate. One of the two reactivities of CDH was selectively knocked down by mutation experiments. CDH‐H28A is much less able to catalyze the CC bond formation, while the ability for CC bond cleavage is still intact. The double variant CDH‐H28A/N484A
THDP依赖性环己烷-1,2-二酮水解酶(CDH)催化的C 环己烷-1,2-二酮的C键裂解成6-氧代己酸酯,和所述不对称苯偶姻苯甲醛和丙酮酸之间的缩合。CDH的两种反应性之一被突变实验选择性地抑制了。CDH-H28A是能够催化与c小得多 C键的形成,而对于C的能力C键裂解仍然完整。双重变体CDH-H28A / N484A表现出相反的行为,并催化将丙酮酸加到环己烷-1,2-二酮中,从而形成叔醇。形成了叔醇的几种酰胆碱,其对映体过量为54-94%。除丙酮酸外,丙酮酸甲酯和丁烷-2,3-二酮是形成CC键的另一种供体底物。因此,通过设计酶变体可以解决非常罕见的醛-酮交叉安息香反应。