title: Autoactivation of pancreatic trypsinogen is controlled by carbohydrate-specific interaction.
abstract: Activation of bovine pancreatic trypsinogen (BPTG) by trypsin (BPT) was found to be inhibited by d GalN/GalNAc at pH 5.5, the pH of secretory granules in the pancreas. Binding studies with biotinylated sugar-polymers indicated that BPTG and BPT bind to α-GalNAc, α-Man, and α-Gal better at pH 5.5 than at pH 7.5. Ultraviolet-difference spectra indicated that BPTG binding to α-GalNAc differs substantially from BPTG binding to other sugars. The N-α-benzoyl-d,l-arginine-p-nitroanilide hydrochloride-hydrolyzing activity of BPT was only slightly affected by these sugars. The results indicate that the binding of GalNAc - containing glycoconjugates protects BPTG from autoactivation, and this may be a self-defense mechanism against intrapancreatic activation.
authors: Graduate School of Humanities and Sciences, Ochanomizu University, Bunkyo-ku, Tokyo 112-8610, Japan; Glycoscience Institute, Ochanomizu University, Bunkyo-ku, Tokyo 112-8610, Japan. Electronic address: ogawa.haruko@ocha.ac.jp.
authors: Haruko
authors: H
authors: Ogawa
authors: Graduate School of Humanities and Sciences, Ochanomizu University, Bunkyo-ku, Tokyo 112-8610, Japan.
authors: Izumi
authors: I
authors: Kusumi
authors: Graduate School of Humanities and Sciences, Ochanomizu University, Bunkyo-ku, Tokyo 112-8610, Japan.
authors: Aya
authors: A
authors: Ogata
authors: Graduate School of Humanities and Sciences, Ochanomizu University, Bunkyo-ku, Tokyo 112-8610, Japan.
authors: Arisa
authors: A
authors: Wada
authors: Graduate School of Humanities and Sciences, Ochanomizu University, Bunkyo-ku, Tokyo 112-8610, Japan.
authors: Hiromi
authors: H
authors: Sakagami
authors: Graduate School of Humanities and Sciences, Ochanomizu University, Bunkyo-ku, Tokyo 112-8610, Japan.
authors: Kana
authors: K
authors: Mitsuhashi
authors: Graduate School of Humanities and Sciences, Ochanomizu University, Bunkyo-ku, Tokyo 112-8610, Japan.
authors: Kimie
authors: K
authors: Date
mesh_terms: D000818:Animals; D002417:Cattle; D004789:Enzyme Activation; D005690:Galactose / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008358:Mannose / Q000378:metabolism; D010179:Pancreas / Q000201:enzymology*; D011485:Protein Binding; D022142:Secretory Vesicles; D014312:Trisaccharides / Q000378:metabolism; D014357:Trypsin / Q000378:metabolism; D014362:Trypsinogen / Q000378:metabolism*
chemical_list: D014312:Trisaccharides; D014362:Trypsinogen; D014357:Trypsin; D008358:Mannose; D005690:Galactose
keywords: Autoactivation-inhibition; Carbohydrate-recognition; Pancreatitis; Self-defense mechanism; Trypsinogen; Zymogen granule