Glutamate dehydrogenase mutants and their application in preparation of L-phosphinothricin

Abstract

The present invention relates to glutamate dehydrogenase mutants and their application in preparation of L-phosphinothricin. The amino acid sequences of the glutamate dehydrogenase mutants are as shown in SEQ ID NO. 1-9, 11, 13, 15, 17-19 and 22. By means of molecular engineering, mutating the specific alanine in glutamate dehydrogenase substrate-binding pocket into glycine and/or mutating the specific valine in glutamate dehydrogenase substrate-binding pocket into alanine, the present invention has obtained NADPH-specific glutamate dehydrogenase mutants with high enzyme activity in catalyzing the substrate 2-oxo-4-[(hydroxy)(methyl)phosphinoyl]butyric acid or its salt for L-phosphinothricin preparation or NADH-specific glutamate dehydrogenase mutants with catalytic activity toward PPO; this has significantly improved substrate conversion, and increased the product concentration of the L-phosphinothricin preparation process.

Dependencies are inferred from the claim text.