In 1989, the Griswold family wasn't so lucky in National Lampoon's Christmas Vacation, the third movie in a franchise that included 1983's inaugural Vacation, 1985's European Vacation and 1997's Vegas Vacation..
1 Pepsin is a protease that begins digestion of proteins, breaking them into peptides and amino acids. 2  Pepsinogen, is secreted by gastric glands of the stomach into the stomach. 3  There, in the acid environment of the stomach, pepsinogen is converted into pepsin.
Pepsin is expressed as a pro-form zymogen, pepsinogen, whose primary structure has an additional 44 amino acids. In the stomach, chief cells release pepsinogen.epsin will digest up to 20% of ingested amide bonds by cleaving preferentially after the N-terminal of aromatic amino acids such as phenylalanine, tryptophan, and tyrosine.