Detection and characterization of native β‐endorphin1–31 in bovine pituitary using electrospray ionization, liquid secondary ion and tandem mass spectrometry

Abstract

AbstractThe molecular ion of intact β‐endorphinbovine, 1–31 (BE), which was extracted from bovine pituitary, was determined by electrospray ionization mass spectrometry. Liquid secondary ion mass spectrometry determined the molecular masses of three peptides produced by trypsin digestion of BE, and tandem mass spectrometry was used to determine the amino acid sequence of the tryptic peptide BE20–24. These data, in combination, were used to characterize BE in bovine pituitary.