Interactions between cyclodextrins and cellular components: Towards greener medical applications?

Leclercq, Loïc

Thaumatins refer to a family of proteins present in the sweetness of the katemfe fruit (Thaumatococcus daniellii Bennett) endemic in West Africa. It is used worldwide in human nutrition and pharmacology as a sweetener, flavor enhancer or to mask bitterness and it is 100,000 times sweeter than sucrose. Thaumatin has been shown to bind to G-protein-coupled receptors (GPCRs) which are transmembrane proteins, responsible for signal transduction. Therefore, the interaction of CDs with thaumatin could be used to modify the interaction of thaumatin with GPCRs and to modify its sweet-taste profile. In this context, Thordarson et al. studied the interaction of α-CD with thaumatin [93] . The 1D and 2D NMR experiments revealed that α-CD binds to aromatic residues of thaumatin with a binding constant of 8.5 M −1 . As the active binding site of the thaumatin protein is known, the authors have synthesized a heptapeptide (Lys-Thr-Gly-Asp-Arg-Gly-Phe) that mimics this binding site of thaumatin. The results show that α-CD binds to the C-terminal solvent accessible phenylalanine residue with a binding constant of 8.8 M −1 . As the α-CD may interact with the active binding site on thaumatin, the regulation of the interaction of thaumatin with GPCRs is probably possible.