Engineering a thermostable transketolase for arylated substrates
Engineering a thermostable transketolase for arylated substrates
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DOI：
10.1039/c6gc02017h
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发表时间：
2017-01-21
期刊：
影响因子：
9.8
通讯作者：
Fessner, Wolf-Dieter
中科院分区：
文献类型：
--
作者：
Saravanan, Thangavelu;Reif, Marie-Luise;Fessner, Wolf-Dieter
芳香族化合物是酶催化立体选择性羰基化反应的难降解底物。我们已经通过定向进化从嗜热脂肪土芽孢杆菌工程化转酮醇酶，以利用芳基烷醛和苯甲醛作为高度立体选择性C-C键形成转化中的亲电底物。发现了具有高达28倍的速率加速的酶变体，其转化2-苯基乙醛、3-苯基丙醛、苯氧基乙醛、苄氧基乙醛和（N-Cbz）-3-氨基丙醛，并以良好的产率（60-72%）和几乎完全的（3S）-立体选择性（> 99%ee）形成相应的芳基取代的1，3-二羟基酮。还发现了用于苯甲醛转化的新型双位点变体。
Aromatic components are difficult substrates for enzymes catalyzing stereoselective carboligation reactions. We have engineered transketolase from Geobacillus stearothermophilus by directed evolution to utilize arylalkanals and benzaldehyde as the electrophilic substrate in highly stereoselective C-C bond forming conversions. Enzyme variants were discovered with rate accelerations up to 28-fold that convert 2-phenylethanal, 3-phenylpropanal, phenyloxyethanal, benzyloxyethanal, and (N-Cbz)-3-aminopropanal with formation of the corresponding aryl-substituted 1,3-dihydroxyketones in good yields (60-72%) and virtually complete (3S)-stereoselectivity (>99% ee). Novel double-site variants were also found for the conversion of benzaldehyde.