Stabilization of somatotropins by modification of cysteine residues utilizing site directed mutagenesis or chemical derivatization.

摘要

The present invention relates to novel modified or derivatized recombinant animal somatotropins. This invention also provides methods for stabilizing recombinant animal somatotropins by modification or deletion of the Cysteine residues utilizing site directed mutagenesis to replace from one to four of the cysteine amino acid residues of said somatotropins with one or more different amino acid residues or by derivatization of (1) both cysteine amino acid residues in the small loop of said somatotropin, both cysteine amino acid residues in the large loop or the four cysteine amino acid residues in both loops of said somatotropin.