Journal Article

N-Glycans Protect Proteins from Protease Digestion through Their Binding Affinities for Aromatic Amino Acid Residues

Tomoko Nishiyama, Naoya Kimura, Yuki Jitsuhara, Makoto Uchida, Fumiko Ochi and Haruki Yamaguchi

in The Journal of Biochemistry

Published on behalf of The Japanese Biochemical Society

Volume 127, issue 3, pages 427-433
Published in print March 2000 | ISSN: 0021-924X
Published online March 2000 | e-ISSN: 1756-2651 | DOI: https://dx.doi.org/10.1093/oxfordjournals.jbchem.a022624
N-Glycans Protect Proteins from Protease Digestion through Their Binding Affinities for Aromatic Amino Acid Residues

Show Summary Details

Preview

It was previously revealed [Yamaguchi, H., Nishiyama, T., and Uchida, M. (1999) J. Bio-chem. 126, 261-265] that N-glycans of both the high-mannose and complex types have binding affinity for aromatic amino acid residues. This study shows that free N-glycans protect proteins from protease digestion through their binding affinities for the aromatic amino acid residues exposed on protein molecules. Protease digestion of bovine pancreatic RNase A and bovine a-lactalbumin was depressed in solutions (1 mM or so) of free N-glycans of both the high-mannose and complex types. The increasing order of the protective effects of the N-glycans paralleled that of their affinities for aromatic amino acid residues; and the presence of aromatic amino acids practically abolished the protective effects of the N-glycans. The N-glycans also depressed the protease digestion of metallothionein, an aromatic amino acid-free protein, in agreement with the observation that the N-glycans also interact with the solvent-exposed aromatic amino acid residues of the proteases. Thus it seems probable that the N-glycans protect proteins from protease digestion by steric hindrance attributable to their binding affinity for the solvent-exposed aromatic amino acid residues of both substrate proteins and proteases.

Keywords: N-glycan; N-glycan function; N-glycan-protein interaction; glycoprotein; protease

Journal Article.  0 words. 

Subjects: Biochemistry

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content. subscribe or login to access all content.