Engineered Assembly of a Protein – Cucurbituril Biohybrid

A crystalline biohybrid with a 4:1 protein:cucurbituril mass ratio is presented. This result was achieved by engineering additional cucurbit[7]uril (Q7) binding sites into a β-propeller protein. In contrast to the parent protein, Q7-controlled assembly of the engineered variant occurred in solution, as evidenced by NMR and SAXS measurements.