| 摘要 |
PROBLEM TO BE SOLVED: To obtain a new D-aminoacylase capable of efficiently producing corresponding D-amino acid from N-acetyl-D,L-amino acid. SOLUTION: This D-aminoacylase has the following physicochemical properties: activity: producing D-amino acid by acting on N-acetyl-D-amino acid; molecular weight: about 36,000 dalton (SDS-PAGE); substrate specificity: acting on N-acetyl-D-methionine, N-acetyl-D-valine, N-acetyl-D-tryptophan or the like and not acting on N-acetyl-L-methionine, N-acetyl-L-leucine or the like; temperature stability: when heat-treated at 30 deg.C, comparatively stable at 40 deg.C but deactivated at >=50 deg.C; optimum temperature: 35 deg.C; optimum pH: 8.0; influence of metal ion: the activity is promoted by 1 mM Co<2+> or Ca<2+> but the activity is inhibited by 1 mM Cu<2+> , Hg<2+> or Zn<2+> . The D-aminoacylase can be obtained by culturing microorganisms bglonging to the genus Amycolatopsis. |
