C-terminal amidating enzyme composition, process for preparing, and use of the same

A C-terminal amidating enzyme composition derived from porcine or equine serum or plasma which comprises a C-terminal amidating enzyme capable of amidating a C-terminal glycine adduct, wherein said amidating enzyme

• (i) amidates the carboxy terminus of the C-terminal glycine of a peptide selected from the group consisting of D-Tyr-Val-Gly, D-Tyr-Trp-Gly, Gly-Phe-Gly, Phe-Gly-Phe-Gly, D-Tyr-Leu-Asn-Gly, Arg-Phe-Gly, Arg-Ala-Arg-Leu-Gly, Leu-Met-Gly, Gly-Leu-Met-Gly, Phe-Gly-Leu-Met-Gly, Asp-Arg-Phe-Gly, Trp-Asp-Arg-Phe-Gly, Ala-Phe-Gly, Lys-Ala-Phe-Gly, Ser-Lys-Ala-Phe-Gly, Arg-Tyr-Gly, Gly-Met-Gly, Gly-Tyr-Gly, Gly-His-Gly, His-Gly-Gly, and Trp-Gly-Gly;
• (ii) is stable in the pH range of 5 to 9;
• (iii) has as cofactors metal ions and L-ascorbic acid;
• (iv) has two active fractions at molecular weights of about 50,000 and about 100,000 as determined from gel filtration;
• (v) has isoelectric points of about 4.5 pH for the active fraction having a molecular weight of about 50,000 and about 6.7 pH for the active fraction having a molecular weight of about 100,000 according to isoelectric point chromatography;
• and
• (vi) is activated by addition of catalase.