α-helix mimicry of a β-turn

It is shown here that the three-dimensional arrangement of the amino acids in an RGDF β-turn (sequence involved in cell adhesion) resembles that of an α-helix with a shuffled RGDF sequence (i.e. RGXFD). A miniprotein was designed and constructed which arranges the RGXFD sequence into a well defined helical conformation. The designed protein is bioactive and folds into the desired structure as assessed by nuclear magnetic resonance spectroscopy. The recognition process mediated by a β-turn can thus be mimicked by an α-helix.