Purification and characterization of rat pepsinogens whose contents increase with developmental progress.
Two pepsinogens, the contents of which increase with developmental progress, were purified from the gastric mucosa of the adult rat by ammonium sulfate fractionation and chromatography on DEAE-cellulose and DEAE-Sepharose CL-6B columns. The purified zymogens, designated as pepsinogens I and II, were each shown to be homogeneous by polyacrylamide gel disc electrophoresis. Pepsinogen II had a greater electrophoretic mobility toward the anode at pH 8.0 than pepsinogen I. The molecular weights of both zymogens were estimated to be 38,000 by SDS-polyacrylamide gel electrophoresis. The activated enzymes, pepsins I and II, each had the same molecular weight of 32,000. The pH optima for both enzymes were found to be 2.0. The enzymes showed high stabilities at pH 8.0, while they lost their activities within 60 min at pH 10.0. The enzymes were inhibited by pepstatin and diazoacetyl-DL-norleucine methyl ester (DAN). The activities of the enzymes in hydrolyzing N-acetyl-L-phenylalanyl-3,5-diiodo-L-tyrosine (APDT) were about 1/8 of that of porcine pepsin. These results suggest that pepsins I and II are very similar.
D000818:Animals; D004355:Drug Stability; D005753:Gastric Mucosa / Q000201:enzymology*; D006863:Hydrogen-Ion Concentration; D007527:Isoenzymes / Q000378:metabolism; D007700:Kinetics; D008970:Molecular Weight; D010434:Pepsin A / Q000378:metabolism; D010435:Pepsinogens / Q000302:isolation & purification / Q000378:metabolism*; D051381:Rats
D007527:Isoenzymes; D010435:Pepsinogens; D010434:Pepsin A