Metabolic Labeling of Glycoconjugates with Photocrosslinking Sugars

Division of Translational Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, USA.
Methods in enzymology (Impact Factor: 2.09). 01/2010; 478:541-62. DOI: 10.1016/S0076-6879(10)78026-5
Source: PubMed

ABSTRACT Protein-carbohydrate interactions play essential roles in a variety of biological processes. This class of interactions is particularly important in development, immunology, infection, and carcinogenesis. However, the transient nature of glycan-dependent interactions hampers efforts to detect and characterize these complexes. Photocrosslinking is emerging as a powerful tool to discover and study glycan-dependent complexes. Through the use of photocrosslinking groups, UV irradiation can be employed to introduce a covalent bond between two transiently interacting molecules. Here we describe the use of metabolic oligosaccharide engineering to incorporate a photocrosslinkable sugar into cellular glycoconjugates and the use of this photocrosslinker to covalently capture glycan-mediated interactions.

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