Purification and primary structure of ostrich pancreatic polypeptide.

Pancreatic polypeptide has been isolated from ostrich pancreas by gel filtration, ion exchange chromatography and high pressure liquid chromatography. The ostrich peptide contains 36 amino acids and has an amino acid composition similar to pancreatic polypeptide of other avian species. The primary structure of ostrich pancreatic polypeptide differs from that of the chicken peptide only at residues 3 and 18 where the ostrich peptide contains an alanine and a valine residue compared to the serine and isoleucine residues found in those positions in the chicken peptide.