Design of stimuli-responsive molecules mimicking dynamic functions of transmembrane proteins

Abstract

Synthetic molecules mimicking the structure and function of proteins gain increasing importance for development of molecular devices and medicines. Membrane proteins are important targets due to their unique functions such as ion transportation and stimuli responsiveness, and give good models for development of synthetic molecular machines. We have been involved in development of amphiphilic multiblock molecules, consisting of linearly connected hydrophilic oligo(ethylene glycol) units and hydrophobic aromatic units, as simple structural mimics of transmembrane proteins. We found that the hydrophobic units of these molecules tend to form face-to-face stacking in a lipid bilayer membrane, to give folded structures as transmembrane proteins, thereby allowing transport of ions across the membrane. This molecular design has an advantage in that the molecules could easily gain stimuli- responsiveness by introducing functional units at the hydrophobic units.