gastrins and sauvagine

A simplified and rapid procedure for the determination of pyroglutamic acid in peptides was developed. The method involves the enzymatic cleavage of an N-terminal pyroglutamate residue using a thermostable pyroglutamate aminopeptidase and isocratic HPLC separation of the resulting enzymatic hydrolysate using a column switching technique. Pyroglutamate aminopeptidase from a thermophilic archaebacteria, Pyrococcus furiosus, cleaves N-terminal pyroglutamic acid residue independent of the molecular weight of the substrate. It cleaves more than 85% of pyroglutamate from peptides whose molecular weight ranges from 362.4 to 4599.4 Da. Thus, a new method is presented that quantitatively estimates N-terminal pyroglutamic acid residue in peptides.

Topics: Amphibian Proteins; Bacillus; Bombesin; Chromatography, High Pressure Liquid; Gastrins; Gonadotropin-Releasing Hormone; Hormones; Humans; Peptide Hormones; Peptides; Pyrococcus; Pyroglutamyl-Peptidase I; Pyrrolidonecarboxylic Acid; Substance P; Thyrotropin-Releasing Hormone