Solid-phase synthesis of a peptide-ligand affinity matrix for isolation of chymosin.

Aminopropyl Perloza beaded cellulose was used as the support for solid-phase synthesis of resin-bound Val-dLeu-Pro-Phe-Phe-Val-dLeu, an inhibitor of aspartic proteases. Both Boc and Fmoc SPPS methodologies were employed in separate syntheses. The peptide-resins were characterized by amino acid analysis. The peptide-resin from the Fmoc synthesis gave the better amino acid analysis of the two syntheses and was used for further studies. Following modification of the peptide N-terminus by succinylation, the peptide-resin was able to bind chymosin (E.C. 3.5.21.4). The peptide resin was used for isolation of chymosin from a crude recombinant broth.