caa a22 4500 397556896 CHVBK 20180308164805.0 cr unu---uuuuu 161202e199608 xx s 000 0 eng 10.1093/oxfordjournals.jbchem.a021427 doi (NATIONALLICENCE)oxford-10.1093/oxfordjournals.jbchem.a021427 Purification and Characterization of Turtle Pepsinogen and Pepsin [Elektronische Daten] [Akira Hirasawa, Senarath B.P. Athauda, Kenji Takahashi] Pepsinogen was purified from the gastric mucosa of soft-shelled turtle (Trwnyx sinensis) by a series of chromatographies on DEAE-cellulose, Sephadex G-100, and Q-Sepharose. Upon chromatography on Q-Sepharose, it was separated into nine isoforms. These isoforms showed a relative molecular mass of approximately 43,000 Da on sodium dodecyl sulfatepolyacrylamide gel electrophoresis, and isoforms 4 through 9 contained carbohydrate (approx. 2% each). Insofar as they were examined, their NH2-terminal sequences differed only in showing substitution at a few positions. At pH 2.0, they were rapidly activated to the corresponding isoforms of pepsin in a stepwise manner. The nine isoforms showed similar specific activity toward hemoglobin and hydrolyzed N-acetyl-L-phenylalanyl- L-diiodotyrosine, a good substrate for pepsin A, at somewhat different rates. They were inhibited by pepstatin to various extents, more strongly than human pepsin C but less strongly than human pepsin A. All isoforms appeared to have similar cleavage specificity toward oxidized insulin B chain, which resembled those of both human pepsins A and C. A cDNA clone for one of the zymogen isoforms was isolated and sequenced. The amino acid sequence thus deduced was more homologous with those of mammalian pepsinogens A than those of mammalian pepsinogens C or prochymoain. © 1996 BY THE JOURNAL OF BIOCHEMISTRY Regular Papers nationallicence amino acid sequence nationallicence cDNA sequence nationallicence pepsin nationallicence pepsinogen nationallicence turtle nationallicence Hirasawa Akira Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo Bunkyo-ku, Tokyo 113 aut Athauda Senarath B.P. Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo Bunkyo-ku, Tokyo 113 aut Takahashi Kenji Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo Bunkyo-ku, Tokyo 113 aut The Journal of Biochemistry Oxford University Press 120/2(1996-08), 407-414 0021-924X 120:2<407 1996 120 jbchem https://doi.org/10.1093/oxfordjournals.jbchem.a021427 text/html Onlinezugriff via DOI 1 other jats NATIONALLICENCE 856 40 https://doi.org/10.1093/oxfordjournals.jbchem.a021427 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Hirasawa Akira Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo Bunkyo-ku, Tokyo 113 aut NATIONALLICENCE 700 1- Athauda Senarath B.P. Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo Bunkyo-ku, Tokyo 113 aut NATIONALLICENCE 700 1- Takahashi Kenji Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo Bunkyo-ku, Tokyo 113 aut NATIONALLICENCE 773 0- The Journal of Biochemistry Oxford University Press 120/2(1996-08), 407-414 0021-924X 120:2<407 1996 120 jbchem Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford