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.
Accordingly, its primary site of synthesis and activity is in the stomach (pH 1.5 to 2). Pepsin exhibits maximal activity at pH 2.0 and is inactive at pH 6.5 and above, however pepsin is not fully denatured or irreversibly inactivated until pH 8.0.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. Pepsin exhibits preferential cleavage for hydrophobic, preferably aromatic, residues in P1 and P1' positions.