The Compositions of Some Peptides Produced by an Enzymic Hydrolysis of Wheat Gliadin

Wheat gliadin was hydrolyzed extensively by treatment with pepsin and then by trypsin. A large number of peptides were produced as well as small amounts of some amino acids, thus indicating a substantial amount of hydrolysis of gliadin by the enzymes. Five peptides were obtained crystalline and two of these constitute 11.5% and 1.2% of gliadin, respectively. Their structures have been partly determined. The results indicate that wheat gliadin contains (Asp.Asp) bonds and at least 1.9% of the glutamic acid is present as glutamylglutamic acid.