Sun Huihui, Gao Wenyuan, Wang Hualei, Wei Dongzhi
State Key Laboratory of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, People's Republic of China.
Biotechnol Lett. 2016 Mar;38(3):455-61. doi: 10.1007/s10529-015-1992-0. Epub 2015 Nov 12.
To identify a novel nitrilase with S-selectivity toward mandelonitrile that can produce (S)-mandelic acid in one step.
A novel nitrilase PpL19 from Pseudomonas psychrotolerans L19 was discovered by genome mining. It showed S-selectivity with an enantiomeric excess of 52.7 % when used to hydrolyse (R, S)-mandelonitrile. No byproduct was observed. PpL19 was overexpressed in Escherichia coli BL21 (DE3) and formed inclusion bodies that were active toward mandelonitrile and stable across a broad range of temperature and pH. In addition, PpL19 hydrolysed nitriles with diverse structures; arylacetonitriles were the optimal substrates. Homology modelling and docking studies of both enantiomers of mandelonitrile in the active site of nitrilase PpL19 shed light on the enantioselectivity.
A novel nitrilase PpL19 from P. psychrotolerans L19 was mined and distinguished from other nitrilases as it was expressed as an active inclusion body and showed S-selectivity toward mandelonitrile.
鉴定一种对扁桃腈具有S选择性的新型腈水解酶，可一步生产（S）-扁桃酸。
通过基因组挖掘发现了一种来自耐冷假单胞菌L19的新型腈水解酶PpL19。当用于水解（R，S）-扁桃腈时，它表现出S选择性，对映体过量为52.7%。未观察到副产物。PpL19在大肠杆菌BL21（DE3）中过表达，形成对扁桃腈有活性且在广泛温度和pH范围内稳定的包涵体。此外，PpL19可水解多种结构的腈；芳基乙腈是最佳底物。对腈水解酶PpL19活性位点中扁桃腈两种对映体的同源建模和对接研究揭示了对映选择性。
挖掘出一种来自耐冷假单胞菌L19的新型腈水解酶PpL19，它与其他腈水解酶不同，因为它以活性包涵体形式表达，并且对扁桃腈表现出S选择性。
