Protease-catalyzed semisynthesis of human neuropeptide Y

Human neuropeptide Y was semisynthesized by enzymatic condensation of des-Tyr36-NH2 human neuropeptide Y and H-Tyr-NH2 using Pseudomonas aeruginosa elastase, a metalloenzyme possessing a hydrolytic specificity for the imino side of hydrophobic amino acids. The optimum pH for this enzymatic synthesis was judged to be around 7 in a high concentration of an organic solvent.