Description

• Application: Pepsin is a peptidase used to digest proteins and is commonly used in the preparation of Fab fragments from antibodies. Pepsin, from porcine gastric mucosa, has been used to hydrolyze dry cervical samples in mice. Product P7000 is provided as a powder and has been used to treat epithelial cells from a single feline mammary carcinoma[1].
• Biochem/physiol Actions: Pepsin hydrolyzes peptide bonds, not amide or ester linkages. Pepsin cleaves peptides with an aromatic acid on either side of the peptide bond. Sulfur-containing amino acids increase susceptibility to hydrolysis when they are close to the peptide bond. Pepsin preferentially cleaves at the carboxyl side of phenylalanine and leucine and at the carboxyl side of glutamic acid residues. Cleaves Phe-Val, Gln-His, Glu-Ala, Ala-Leu, Leu-Tyr, Tyr-Leu, Gly-Phe, Phe-Phe and Phe-Tyr bonds in the β chain of insulin Pepsin is the major proteolytic enzyme produced in the stomach. It digests proteins through the cleavage of interior peptide linkages.[5].
• Unit Definition: One unit will produce a ΔA280 of 0.001 per min at pH2.0 at 37 °C, measured as TCA-soluble products using hemoglobin as substrate. (Final volume = 16ml. Light path = 1cm.)
• Analysis Note: Optimum pH is 2-4. Active in 4 M urea and 3 M guanidine HCl. Stable at 60 °C. Pepsin is irreversibly inactivated at pH 8.0 - 8.5.
• Other Notes: View more information on pepsin at www.sigma-aldrich.com/enzymeexplorer.