Combination of Glycosyltransferases and a Glycosynthase in Sequential and One‐Pot Reactions for the Synthesis of Type 1 and Type 2 N‐Acetyllactosamine Oligomers

Abstract

In three words,h ow would you describe your research?Retrosynthetic biocatalysis (of) glycoconjugates. What aspects of this project do you find most exciting?The presented results were only possible by the joint expertise of two research groups and their dedicatedd octoral students within the DFG InternationalR esearch TrainingG roup "SeleCaSelectivity in Chemo-and Biocatalysis" at RWTH Aachen University and Osaka University.T he Elling group is interested in the synthesis of glycan ligands and glycan inhibitors of galectins, al ectin class involved in tumor biology.W ew ere wondering about the possibility to synthesize oligomers with type 1 N-acetyllactosamine (LacNAc) repeats( yellow/blue sugar combination in the cover picture),w hich is known as an unusual glycan structure in somec ancer types. For this goal the expertise of the Pietruszkag roup in the use of glycosynthases was highly valuable. The combination of two glycosyltransferases (blue and red protein structures) and one galactosynthase (yellow protein structure) renders al ibrary of novel polyLacNAc structures (the yellow/blue and red/blue sugars) in different combinations.T he most exciting aspect is that polyLacNAc oligomers-not yet found in nature-presenting alternating type 2/type 1L acNAc structures can now be studied for galectin binding and inhibition. What was the inspiration for this cover design?Biocatalysis and especially multi-enzyme systems are av iable alternative fort he synthesis of complex glycan structures. The propera daptation of reaction conditions makes "juggling" with as et of enzymesp ossible. We present novel glycoconjugates, not yet realized by chemical carbohydrate synthesis. Dedication and AcknowledgementsOur paper is dedicated to our colleague Prof. Dr.W olf-Dieter Fessner on the occasion of his 60 th birthday.W ea cknowledge financial supporto fo ur work, as well as the realization of this cover picture, by the DFG within the IRTG 1628 "SeleCa".