Proteins pinned together using linking ligands can assemble themselves into elaborate structures. Now, a team that included Soochow University scientists has developed a protein–ligand combination that forms a two-dimensional triangular lattice.

They created this self-assembled pattern based on the observation that certain proteins feature non-covalent binding sites for carbohydrate molecules. Wheat germ agglutinin (WGA) protein naturally forms dimers that possess four strong carbohydrate binding sites on one side of the structure, and four weakly binding sites on another side.

By creating a short ligand that would connect two WGA dimers via their carbohydrate binding sites, the team produced a system in which multiple proteins would join together in large arrays, linked by the ligand. Due to the position and angle of the carbohydrate’s binding sites, the WGAs initially self-assembled into clusters of three, featuring a tringle-shaped void in the cluster’s centre. These clusters connect with other clusters to form further triangle shapes within a highly regular repeating array.