Isolation and structure determination of the peptides from the chymotryptic hydrolysate of the alkaline protease from Aspergillus flavus

From the chymotryptic hydrolysate of 1.08 g of the precipitate obtained on treatment of alkaline protease from Aspergillus flavus with trichloracetic acid 134 peptides were isolated by means of ion exchange chromatography, paper electrophoresis and paper chromatography. Among these 38 peptides containing 311 amino acids were isolated in amounts exceeding 0.50μmol. The peptides were characterized by amino acid analysis, electric charge and also mostly by the terminal groups determination. In the case of peptides isolated in larger amounts the complete or at least the partial sequence of amino acids has been determined. In all peptides the total isolated amount in μmol was determined. The peptides containing basic amino acids were subfractionated with trypsin.