We are dedicated to Glycobiotechnology
Glycans are considered as future target molecules in the fields of biomedicine, pharmacy, cosmetics and nutrition. Glycoconjugates (e.g. glycoproteins, glycolipids), hormones and antibiotics bear complex oligosaccharides as essential building blocks, of which a majority play important roles as multifunctional information carriers for inter- and intracellular communication. The diversity of glycoconjugates promises many diagnostic and therapeutic applications.
In this context, one long-term aim of our research projects is the synthesis of biologically relevant carbohydrate structures/libraries by defined enzyme systems and the characterization of their binding properties to lectins (glycan binding proteins). The most promising candidates are conjugated to carrier scaffolds in order to generate multivalent neo-glycoconjugates for specific and firm binding of human galectins and bacterial toxins. The bottleneck for the synthesis of such glycoconjugates consists still in the quantity of the ‘glyco’-moiety. We use ‘retro-synthetic biocatalysis’ including glycosidases/glycosynthases and Leloir-glycosyltransferases as catalytic tools with outstanding stereo‑/regioselectivity and unbeatable advantages of cascade, telescoping, one-pot reactions and in situ substrate regeneration cycles. However, there is a huge need of activated sugars (nucleotide sugars) as donor substrates. For this reason, another long-range objective is the ‘Golgi Glycan Factory’ that combines several enzymes in modules. The modularization is the key element for establishing assembly lines for natural and modified glycoconjugates. We are thus able to produce ‘on-demand’, exemplified by the generation of activated nucleotide sugars (gram scale), nature-like glycans, human milk oligosaccharides and hyaluronic acid.