Small Molecule Glycosylation – a Powerhouse in Synthetic Biology

Small molecule glycosyltransferases or UGTs are the “awesome office managers” of Nature, making sure everything gets made in the right way, gets to the right location and gets stored for easy retrieval when needed. UGT stands for “UDP-glucose dependent Glycosyl Transferase” and close to 10,000 such enzymes were annotated by the start of 2016 (www.cazy.org). Plants are particularly rich sources, each having from 100-300 UGTs, but most if not all living organisms have them. UGTs are employed for de-toxification before either excretion (animals) or storage (plants), for stabilization of unstable molecules (e.g. cyanogenic glycosides and anthocyanins) or for attaining precise functionality (e.g. rebaudioside sweeteners and saponins).

The de-toxification aspect is particularly interesting as this allows for biological production of molecules otherwise harmful to the producing organism but the often accompanying increase in watery solubility can be of equal importance. Obtaining the right functionality of molecules by complex glycosylation is of obvious importance but requires deep knowledge on UGT specificity. Evolva has for many years been developing a state-of-the-art UGT platform and used this for current or near-to-market products such as Vanillin and Stevia sweeteners, but also for a large number of pipeline products.

The use of small molecule glycosylation in current and future Evolva ingredients will be discussed as will a number of the detailed studies that led to the success of the UGT platform.

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