The Role of Ligand Density in the Enzymatic Glycosylation of Carbohydrates Presented on Self-Assembled Monolayers of Alkanethiolates on Gold

The biological activity of immobilized carbohydrates can show a dramatic dependence on the density of carbohydrate. This is the result of investigations with self-assembled monolayers that present N-acetylglucosamine groups as a model substrate for glycosylation by bovine β-1,4-galactosyltransferase (GalTase; see picture). Surface plasmon resonance spectroscopy and carbohydrate-binding lectins were used to characterize the reaction at the interface. UDP-Gal=uridine diphosphogalactose.