Carbohydrate-Active enZyme (CAZyme) enabled glycoengineering for a sweeter future

One of the stumbling blocks to advance the field of glycobiology has been the difficulty in synthesis of bespoke carbohydrate-based molecules like glycopolymers (e.g. human milk oligosaccharides) and glycoconjugates (e.g. glycosylated monoclonal antibodies). Recent strides towards using engineered Carbohydrate-Active enZymes (CAZymes) like glycosyl transferases, transglycosidases, and glycosynthases for glycans synthesis has allowed production of diverse glycans. Here, we discuss enzymatic routes for glycans biosynthesis and recent advances in protein engineering strategies that enable improvement of CAZyme specificity and catalytic turnover. We focus on rational and directed evolution methods that have been developed to engineer CAZymes. Finally, we discuss how improved CAZymes have been used in recent years to remodel and synthesize glycans for biotherapeutics and biotechnology related applications.