An Effective Bacterial Fucosidase for Glycoprotein Remodeling

Fucose is an important component of many oligo- and polysaccharide structures as well as glycoproteins and glycolipids, which are often associated with a variety of physiological processes ranging from fertilization, embryogenesis, signal transduction, and disease progression, such as rheumatoid arthritis, inflammation, and cancer. The enzyme α-l-fucosidase is involved in the cleavage of the fucosidic bond in glycans and glycoconjugates, particularly the Fuc-α-1,2-Gal, Fuc-α-1,3/4-GlcNAc, and Fuc-α-1,6-GlcNAc linkages. Here, we report a highly efficient fucosidase, designated as BfFucH identified from a library of bacterial glycosidases expressed in E. coli from the CAZy database, which is capable of hydrolyzing the aforementioned fucosidic linkages, especially the α-1,6-linkage from the N-linked Fuc-α-1,6-GlcNAc residue on glycoproteins. Using BfFucH coupled with endoglycosidases and the emerging glycosynthases allows glycoengineering of IgG antibodies to provide homogeneous glycoforms with well-defined glycan structures and optimal effector functions.