Patent ID: 6403342
Filing Date: 2002-06-11
Classification: C12N,C12P

Abstract:
An isolated DNA comprising (A) or (B): wherein,(A) a DNA coding for a protein having &agr;-isopropylmate synthase activity and an amino acid sequence shown in SEQ ID NO: 2 which has a substitution selected from the following (a) to (e): (a) a substitution of another amino acid residue for a threonine residue at position 482, (b) a substitution of another amino acid residue for a glutamic acid residue at position 386, (c) a substitution of another amino acid residue for a proline residue at position 428, (d) a substitution of another amino acid residue for a glycine residue at position 479, and (e) a substitution of another amino acid residue for a glycine residue at position 462, (B) a DNA obtained by subjecting the DNA of (A) to mutagenesis and selecting a DNA coding for a protein having an &agr;-isopropylmalate synthase activity and feedback inhibition of the activity by L-leucine being desensitized equivalently to that of the protein encoded by the DNA of (A).