Immobilization of carbohydrate epitopes for surface plasmon resonance using the Staudinger ligation.
The detection of carbohydrate-protein interactions is often performed using techniques that require surface immobilization of the lectin or the glycan. A commonly used assay for lectin binding is surface plasmon resonance (SPR). We describe an implementation of the Staudinger ligation as a method to immobilize carbohydrate epitopes to a biosensor surface. This was accomplished by first introducing an azide functionality to a carboxymethyldextran surface, followed by reaction with a phosphane-modified carbohydrate ligand. The chemistry employed is extremely mild and was easily adapted to a commercial biosensor system. Using this approach, we investigated the binding of jacalin and wheat germ agglutinin (WGA) to galactose, lactose, and N-acetyl-lactosamine. We observed that WGA binding shows evidence of multivalent interaction with the surface. Additionally, we found that jacalin binding was influenced by the presence of a flexible and hydrophobic galactosyl aglycone.
Alberta Ingenuity Centre for Carbohydrate Science, Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada.
Ravi S
RS
Loka
Christopher W
CW
Cairo
D000939:Epitopes / Q000737:chemistry*; D037102:Lectins / Q000737:chemistry; D015394:Molecular Structure; D037121:Plant Lectins / Q000737:chemistry; D020349:Surface Plasmon Resonance / Q000379:methods*; D014909:Wheat Germ Agglutinins / Q000737:chemistry
D000939:Epitopes; D037102:Lectins; D037121:Plant Lectins; D014909:Wheat Germ Agglutinins; C043696:jacalin