The invention discloses an aspartase
mutant, which comprises the following mutations M321V, K324T and N326S on an
amino acid sequence represented by SEQ ID NO.2, and has high enzymatic activity compared with wild-type aspartase in
catalysis of (E)-4-(2,4,5-trifluorophenyl)2-butenoic acid. The invention also discloses applications of the aspartase
mutant in preparation of (R)-3-amino-4-(2,4,5-trifluorophenyl)-
butyric acid. According to the invention, with the application of the aspartase
mutant in an
enzyme catalytic reaction to prepare a
sitagliptin chiral intermediate (R)-3-amino-4-(2,4,5-trifluorophenyl)-
butyric acid, the conversion rate is high, the
stereoselectivity is high, the yield is high, the production cost is low, the environment is friendly, and industrial large-scale production is facilitated.