| 摘要 |
A human manganese superoxide dismutase (Mn-SOD) having an elevated isoelectric point and an increased capability of tissue penetration is prepared by replacing an amino acid residue present at the site which does not affect the enzymatic activity even when another amino acid residue is present thereat in the amino acid sequence of the dismutase by a more positively charged amino acid residue. Examples thereof include one prepared by replacing the 4th serine residue on the N-terminal side of a recombinant human variant Mn-SOD by a basic amino acid residue and one prepared by replacing, in addition to the 4th amino acid residue, the 42nd glutamic acid residue by a valine residue. These human variant Mn-SODs have an excellent drug activity on various diseases on which the conventional Mn-SOD is insufficiently efficacious, for example, various inflammatory diseases caused by active oxygen, cancer, retinopathy of prematurity, hypertension and diabetes. Further they are useful as a cosmetic ingredient. |
