Pepsinogens and pepsins from gastric mucosa of Japanese Monkey. Purification and characterization.
Five pepsinogens were purified from gastric mucosa of Japanese monkey by DEAE-cellulose column chromatography and Sephadex G-100 gel filtration. Each was shown to be homogeneous by polyacrylamide disc gel electrophoresis. They were designated as pepsinogens I, II, III-1, III-2, and III-3, respectively, based on the elution profile on DEAE-cellulose chromatography. The molecular weights of pepsinogens I and II were 48,000 and 43,000, respectively, and those of the other three were 40,000. Each pepsinogen was converted to pepsin [EC 3.4.23.1] by acidification, and some characteristics, e.g. the pH dependence of activity, sensitivity to various inhibitors, stability to alkali, and hydrolytic activity toward N-acetyl-L-phenylalanyl-3,5-diiodo-L-tyrosine (APDT), were determined. The characteristics of pepsins I and II were the same, and those of pepsins III-1, III-2, and III-3 were similar. Pepsin III-3 showed high stability to alkali (pH 8.0), while the others were less stable. Each pepsin hydrolyzed APDT and was inhibited by acid protease-specific inhibitors, e.g. pepstain, diazoacetyl-DL-norleucine methyl ester (DAN), 1,2-epoxy-3-(p-nitrophenoxy)propane (EPNP), and p-bromophenacyl bromide. The compositions of pepsins I and II were the same, indicating that they are the same protein, and those of pepsins III-1, III-2, and III-3 resembled that of human pepsin. The diversity of pepsinogens and pepsins is discussed in comparison with pepsinogens and pepsins from other animals.
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D005260:Female; D005753:Gastric Mucosa / Q000201:enzymology*; D000882:Haplorhini; D008251:Macaca; D008297:Male; D008970:Molecular Weight; D010434:Pepsin A / Q000378:metabolism*; D010435:Pepsinogens / Q000302:isolation & purification / Q000378:metabolism*; D010436:Pepstatins / Q000494:pharmacology; D011489:Protein Denaturation
D000596:Amino Acids; D010435:Pepsinogens; D010436:Pepstatins; D010434:Pepsin A