1998 Volume 56 Issue 2 Pages 125-133
To create artificial ion channels using synthetic peptides is one of the challenges of the de novo design of artificial proteins not only to obtain highly functional artificial molecules but also to understand the basic mechanisms of natural ion channel proteins. Amphiphilic helical peptides of 20 amino acid residues were reported to assemble with each other in lipid bilayers to form ion channels. To obtain more organized channels, efforts have been directed toward controlling the assembly by template molecules. Not only α-helical peptides, but also peptide nanotubes and gramicidin-like molecules were developed as channel molecules where the assembly was stabilized by hydrogen bonding between the molecules. We have developed three approaches to construct artificial helical proteins comprising helices with individual amino acid sequences. Using one of these approaches, four helices corresponding to the voltage sensor (S 4 in repeat I-IV) of the sodium channel were tethered on a peptide template to afford a protein having ion channel activity with rectification.
