Martina Delbianco

Natural biopolymers have inspired the development of synthetic analogues – i.e. foldamers – capable of adopting defined conformations and forming programmable three-dimensional architectures. These compounds are mainly based on peptides and nucleic acids, that are well understood at the molecular level. In contrast, the complexity of carbohydrate synthesis and structural analysis have prevented access to synthetic carbohydrates capable of adopting defined geometries. 

With automated glycan assembly (AGA), we prepared well-defined oligo- and polysaccharides resembling natural as well as unnatural structures.^[1] These synthetic glycans are ideal probes for the fundamental study of polysaccharides, shedding light on how the primary sequence affects the polysaccharide shape. Molecular dynamics simulations, NMR spectroscopy, and single molecule imaging allowed for the visualization of polysaccharides’ conformation and revealed that some polymers form helices while others adopt rod-like structures.^[2] 

These synthetic oligosaccharides are capable of self-assembling into nanostructures of varying morphologies. Microcrystal electron diffraction (MicroED) permitted to explore the supramolecular architecture and correlate it to the local organization, delivering important information on the system chirality.^[3] 

References: 

[1] M. Delbianco, A. Kononov, A. Poveda, Y. Yu, T. Diercks, J. Jiménez-Barbero, P. H. Seeberger, J. Am. Chem. Soc. 2018, 140, 5421-5426. 

[2] X. Wu, M. Delbianco, K. Anggara, T. Michnowicz, A. Pardo-Vargas, P. Bharate, S. Sen, M. Pristl, S. Rauschenbach, U. Schlickum, S. Abb, P. H. Seeberger, K. Kern, Nature 2020, 582, 375-378. 

[3] G. Fittolani, D. Vargová, P. H. Seeberger, Y. Ogawa, M. Delbianco, J. Am. Chem. Soc. 2022, 144, 12469-12475.