7146. Pepsin

Nomenclature

CAS number: 9001-75-6
Puerzym (Firma).

Description and references

Principle digestive enzyme of gastric juice; controls the degradation of proteins to proteoses and peptones. Distinctive among enzymes for having a very low isoelectric point and a very low pH optimum. Hydrolyzes only peptide linkages. The N.F. grade digests not less than 3000 or more than 3500 times its wt of freshly coagulated and disintegrated egg albumin in 2 1/2 hours at 52° in water acidulated with HCl. Isoln from gastric juice of swine and beef: Northrup, J. Gen. Physiol. 13, 739 (1930); 16, 615 (1933); from salmon and tuna: Norris, Edam, J. Biol. Chem. 134, 443 (1940); 204, 673 (1953). Amino acid composition: Brand in Crystalline Enzymes, J. H. Northrup et al. (Columbia Univ. Press, New York, 2nd ed., 1948) p 26. Active site: Herriott, J. Gen. Physiol. 45, Suppl., 57 (1962). Review: Bovey, Yanari in The Enzymes vol. 4, P. D. Boyer et al., Eds. (Academic Press, New York, 1960) pp 63-92.

Properties

White or yellowish-white translucent scales or granules, or an amorphous slightly hygroscopic powder, or spongy masses. It has a slightly acid or saline taste. [α]D26 -64.5° (water pH 4.6). Isoelectric point <pH 1.0. Freely sol in water with more or less opalescence. Practically insol in alc, chloroform, ether. Very stable to acid. The activity of pepsin in solns is destroyed by heating above 70°, or by alkalies; dry pepsin is not injured by heating to 100°. Incompat. Alc, tannin, alkaline substances and salts of heavy metals. Note: Pepsin of an activity of 4000, 5000, 6000, 10,000, 15,000, and 20,000 is likewise available, and it has also been obtained in pure crystalline form.

Therapeutic Category

Enzyme (digestive).

Therapeutic Category (Veterinary)

Has been used as a digestive aid in deficiency of pepsin secretion.

Keywords

Digestive Aid; Enzyme; Digestive