Aminoquinoline Fluorescent Labels Obstruct Efficient Removal of N-Glycan Core α(1-6) Fucose by Bovine Kidney α-l-Fucosidase (BKF).

Here we report evidence that new aminoquinoline N-glycan fluorescent labels interfere with the release of core α(1-6) fucose from N-glycans by bovine kidney α-l-fucosidase (BKF). BKF is a commonly employed exoglycosidase for core α(1-6) fucose determination. Molecular simulations of the bound and unbound Fuc-α(1-6)-GlcNAc, where GlcNAc is situated at the reducing end for all N-glycans, suggest that the reduced BKF activity may be due to a nonoptimal fit of the highest populated conformers in the BKF active binding site at room temperature.