Enzymatic Synthesis of Complex Carbohydrates

Complex saccharides are highly diverse in structure and biological functions. Accordingly, they are essential for many fields of research. The development of efficient synthetic methodologies for their preparation has thus been in high demand. The chemical synthesis of complex oligo- and polysaccharides, however, is often limited to the milligram scale and is difficult to scale up. Enzymatic synthesis, in contrast, offers an alternative that overcomes these limitations due to the high catalytic activity, lack of undesirable side reactions, mild reaction conditions, and high regio- and stereoselectivity of enzymes. This chapter will outline the development and applications of the following three types of enzymes used in the enzymatic biosynthesis of complex carbohydrates: glycosidases, glycosynthases, and glycosyltransferases.