HUMAN RIBONUCLEASE A WITH REDUCED RIBONUCLEASE INHIBITOR AFFINITY

摘要

Modified ribonucleases belonging to the RNase A superfamily of ribonucleases is disclosed. Each modified ribonuclease has a mutation in the loop region corresponding to amino acids 85-94 of bovine pancreatic RNase A. Each modified ribonuclease has reduced binding affinity for ribonuclease inhibitor (RI), wild-type ribonuclease activity, and exhibits enhanced cytotoxicity toward tumor cells, relative to the wild-type ribonuclease. Also disclosed is a method for obtaining a modified ribonuclease having reduced binding affinity for RI, wild-type ribonuclease activity, and enhanced cytotoxicity.