摘要

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 alpha-GalNAc, alpha-Man, and alpha-Gal better at pH 5.5 than at pH 7.5. Ultraviolet-difference spectra indicated that BPTG binding to alpha-GalNAc differs substantially from BPTG binding to other sugars. The N-alpha-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.

  • 出版日期2015-2-27

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