Barrel assembly senses glycolipids

Abstract

Sensors that selectively detect glycolipids—molecules that are involved in infection, inflammation, and cancer progression—are hard to make. Most sensors target either the hydrophilic sugar head group or the hydrophobic lipid tail. A new supramolecular sensor has components that bind both parts of the glycolipid, Timothy E. Glass of the University of Missouri reported at the ACS meeting last week. The work was also published earlier this month (Angew. Chem. Int. Ed. 2018, DOI: 10.1002/anie.201807221). Glass’s supramolecular sensor comprises a hydrophobic cavity made from a barrel-shaped cucurbituril molecule, a boronic acid-based carbohydrate receptor, and a fluorescent indicator dye. The receptor stays put in the cavity because a bis-pyridinium group anchors it there. This positively charged anchor region also quenches the dye, which accompanies the receptor in the cavity. When the boronic acid receptor binds the sugar head group of a glycolipid, the lipid tail displaces the dye, which is then free