Related Experiment Video
Updated: Jul 5, 2026

Pulse-chase Analysis of N-linked Sugar Chains from Glycoproteins in Mammalian Cells
Published on: April 27, 2010
Release of saccharides from glycoconjugates
L D Powell1, A P Varki, H H Freeze
1University of California San Diego, La Jolla, California, USA.
Abstract:
Glycosidases are specific enzymes that can partially or completely remove sugar chains from cell-surface glycoconjugates. The enzymes can be exoglycosidases (which remove a terminal saccharide unit from an oligosaccharide chain), endoglycosidases (which cleave within an oligosaccharide chain, releasing an oligosaccharide fragment), or glycoamidases (which cleave between an oligosaccharide unit and its N-linkage to a protein). Commonly used examples of each enzyme are presented in this unit. Sialidase digestion of purified proteins is described and an Alternate Protocol details the application of the technique to intact cell suspensions. A support protocol describes testing sialidase activity in a variety of buffers. Basic protocols are detailed for the digestion of intact glycoproteins and glycopeptides by the most common endoglycosidases and glycoamidases: Endoglycosidase H (Endo H), Endoglycosidase F2 (Endo F2), and Peptide:N-glycosidase F (PNGase F). The applications described in the second and third support protocols employ these enzymes alone or as part of a sequential digestion. The second support protocol describes how to use partial digestions with one enzyme or sequential digestions with different enzymes to estimate the number or types of N-linked carbohydrate chains on a protein. The third support protocols describes sample preparation and digestion followed by gel-filtration chromatography to recover the released radiolabeled oligosaccharide chains for subsequent analysis.
Related Concept Videos
Oligosaccharide Assembly
Multiple sugar molecules that may or may...
Proteoglycans
Protein Glycosylation
Glycosylation occurs in...
Carbohydrate Metabolism
Starch accounts for approximately 60% of the carbohydrates consumed by humans. Since amylase enzymes cannot function in the stomach's acidic environment, starch can only be digested in the mouth and small intestine. Simple sugars are found naturally in milk and fruits in the...
Chemistry of Carbohydrates
Overview of Carbohydrate Metabolism
Glucose transport into cells is facilitated by a family of transport proteins called GLUT (Glucose Transporters). GLUT4 is the primary glucose transporter for insulin-stimulated glucose...
