Molecular Basis for the High Activity and Enantioselectivity of the Carbonyl Reductase from Sporobolomyces salmonicolor toward α-Haloacetophenones
In an effort to develop a practical method for the synthesis of optically pure 2,2,2-trifluoro-1-phenylethanol,we found that the carbonyl reductase(SSCR)from Sporobolomyces salmoni-color showed excellent activity and enantioselectivity toward the halogenated acetophenones.Especially,SSCR exhibited more than 1000 times higher activity toward α,α,α-trifluoroacetophenone than unsubstituted acetophenone a strikingly different observation from the previously well-studied alcohol dehydrogenase(LBADH)from Lactobacillus brevis.Enzyme-substrate docking and site-directed mutagenesis studies revealed the molecular basis for the high enzyme activity and enantioselectivity of SSCR toward the α-halogenated acetophenones.The hydrogen bond of the Asn207 side chain with the substrate halogen atom and the XH/π interaction of the substrate phenyl group with the side chains of Ser222/Thr223 resulted in the formation of the highly reactive conformation of α-halogenated acetophenones in the active site of the enzyme.(S)-2,2,2-Trifluoro-1-phenylethanol was prepared in excellent isolated yield and enantiomeric excess from the reduction of α,α,α-trifluoroacetophenone with mutant T209A.These results suggest that tuning the interactions between the halogen atoms/phenyl group of the substrate and the amino acid residues of the enzyme would lead to valuable mutants for the practical synthesis of β-haloalcohols.
α-haloacetophenones carbonyl reductase enzymatic reduction site-directed mutagenesis substrate-binding mechanism
Xi Chen Hongliu Zhang Jinhui Feng Qiaqing Wu Dunming Zhu
National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Research Center of Biocatalytic Technology,Tianjin Institute of Industrial Biotechnology,Chinese Academy of Sciences,Tianjin,300308,China
国内会议
第九届国际分子模拟与信息技术应用学术会议(ICMS&I2018)
太原
英文
295-301
2018-05-01（万方平台首次上网日期，不代表论文的发表时间）