Patent ID: 7163814

Claim:
An isolated βketo acid reductase comprising the amino acid sequence of SEQ ID NO:1 except that: (a) the amino acid at amino acid position 54 is substituted with glutamine, glycine, serine, threonine, cysteine, asparagine, alanine valine, isoleucine, methionine, lysine, arginine, aspartic acid, glutamic acid, tyrosine, proline or histidine; the amino acid at amino acid position 245 is substituted with arginine or another amino acid; and the amino acid at position 271 is substituted with asparagine or another acid; (b) the amino acid at amino acid position 104 is substituted with cysteine; the amino acid at amino acid position 245 is substituted with arginine or another amino acid; and the amino acid at position 271 is substituted with asparagine or another acid; or (c) the amino acid at amino acid position 54 is substituted with glutamine, glycine, serine, threonine, cysteine, asparagine, alanine valine, isoleucine, methionine, lysine, arginine, aspartic acid, glutamic acid, tyrosine, proline or histidine; the amino acid at amino acid position 104 is substituted with cysteine; the amino acid at amino acid position 245 is substituted with arginine or another amino acid; and the amino acid at position 271 is substituted with asparagine or another acid.