High Thermal Stability Imparted by a Designed Tandem Arg–Trp Stretch in an α‐Helical Coiled Coil

Let's twist again: A cation–π interaction between Trp and Arg is designed at the interface between two α helices of a coiled-coil structure and stabilizes the structure more than Glu and Lys ion-pair interactions. Two or three Trp–Arg sets form an extended array of interactions (see picture) and increase the melting temperature of the peptide.