Molecular Recognition of Proteins by Cucurbiturils

In this chapter, an overview is provided of the different concepts of cucurbiturils directly interacting with epitopes on proteins. This overview also serves as an illustration of the potential of this highly efficient supramolecular chemistry on proteins. Cucurbiturils are ideally suited for the recognition of protein elements, because of their combined hydrophobic and polar recognition motifs and hand-in-glove steric match with selected amino acid residues. Especially, the diverse chemical characteristics of cucurbit[6]uril, cucurbit[7]uril, and cucurbit[8]uril have been shown to be ideally suited to bind different molecular epitopes on proteins, including two-fold epitope binding by cucurbit[8]uril, as illustrated via examples on N-terminal and mid-chain amino acid binding as well as multiple amino acid epitope recognition. Clever molecular recognition concepts and protein engineering allows for functional modulation and study of protein activity or controled protein assembly by virtue of the cucurbituril recognition. Enzyme activity regulation, inhibition of amyloid aggregation, directed protein-wire assembly, and generation of supramolecular biopharmaceuticals are highlights of the potential of the concept of molecular recognition of proteins by cucurbiturils.