A novel broad specificity fucosidase capable of core α1-6 fucose release from N-glycans labeled with urea-linked fluorescent dyes

Exoglycosidases are often used for detailed characterization of glycan structures. Bovine kidney α-fucosidase is commonly used to determine the presence of core α1-6 fucose on N- glycans, an important modification of glycoproteins. Recently, several studies have reported that removal of core α1-6-linked fucose from N- glycans labeled with the reactive N- hydroxysuccinimide carbamate fluorescent labels 6-aminoquinolyl- N- hydroxysuccinimidylcarbamate (AQC) and RapiFluor-MS is severely impeded. We report here the cloning, expression and biochemical characterization of an α-fucosidase from Omnitrophica bacterium (termed fucosidase O). We show that fucosidase O can efficiently remove α1-6- and α1-3-linked core fucose from N -glycans. Additionally, we demonstrate that fucosidase O is able to efficiently hydrolyze core α1-6-linked fucose from N- glycans labeled with any of the existing NHS-carbamate activated fluorescent dyes.