Amino acid dehydrogenase mutant and application in synthesis of L-glufosinate-ammonium thereof

An amino acid dehydrogenase mutant, wherein the amino acid dehydrogenase mutant is obtained by a single mutation or multi-site mutations of the amino acid at position 95, 108, 172, 303 of the amino acid sequence shown in SEQ ID NO:

• 2, wherein the single mutation or the multi-site mutations is/are selected from the group consisting of:
• (1) phenylalanine at position 95 of the amino acid sequence shown in SEQ ID NO:
• 2 into leucine or isoleucine;
• (2) phenylalanine at position 95 of the amino acid sequence shown in SEQ ID NO:
• 2 into leucine, and alanine at position 108 into threonine, serine or tyrosine;
• (3) phenylalanine at position 95 of the amino acid sequence shown in SEQ ID NO:
• 2 into isoleucine, and arginine at position 172 into proline or valine;
• (4) phenylalanine at position 95 of the amino acid sequence shown in SEQ ID NO:
• 2 into isoleucine, alanine at position 108 into threonine, and arginine at position 172 into proline or valine;
• (5) phenylalanine at position 95 of the amino acid sequence shown in SEQ ID NO:
• 2 into isoleucine, alanine at position 108 into tyrosine, and arginine at position 172 into proline;
• and
• (6) phenylalanine at position 95 of the amino acid sequence shown in SEQ ID NO:
• 2 into isoleucine, alanine at position 108 into threonine, arginine at position 172 into proline and arginine at position 303 into histidine.