Communication
Oligo-(1→2)-α-D-glucopyranosyl-(1→2)-β-D-fructofuranosides Form Tight Sugar Coils†
†
This work was supported by the Deutsche Forschungsgemeinschaft. The authors thank Edelgard Herold for help in the preparation of the oligosaccharides.
Graphical Abstract
The cyanobacterial oligosaccharides [α-D-Glc(1→2)]n-β-D-Fru (n≤9) form right-handed helices with a tetrasaccharide repeat, a diameter of 12 Å, and a pitch of 5 Å. The vicinal α-(1→2)-glycosidic linkages stabilize this compact helix with a significant energy barrier of unwinding. Kojiheptaose (n=7) with a fructofuranose terminus is the smallest biopolymer with an unfolding barrier observable by NMR spectroscopy.
