THE DIGESTION OF LULIBERINE ANALOGS CONTA INING D-ALANINE RESIDUE BY HUMAN GASTRIC-JUICE

The digestion of surphagone and other luliberine analogues containing residues of D-amino acids by human gastric juice was studied. By means of chromatography and mass spectrometry, these peptides were shown to undergo hydrolysis of the bond formed by D-Ala at the P-1 position, a nd this hydrolysis was shown to be catalyzed by gastricsin rather than pepsin A, Gastricsin was assumed to be a highly specific protease, Th e results are in a good agreement with the concept of conformational s pecificity of proteases towards the natural oligopeptides.