ARTIFICIAL ION CHANNELS Peptide nanotubes rival nature's own

Abstract

Chemists at Scripps Research Institute, La Jolla, Calif., have found a way to induce simple peptide subunits to assemble themselves into artificial ion channels that span a lipid membrane. The resulting channels—known as peptide nanotubes—allow ions to zip through the membrane more quickly than in many natural ion channels. The team's work is published in last week's Nature [ 369 ,301 (1994)]. Wider versions of these channels may provide a convenient route for delivering drug molecules into living cells. The channels also may find use in gene therapy and related biomedical applications, according to the researchers, M. Reza Ghadiri, Juan R. Granja, and Lukas K. Buehler. Late last year, Ghadiri, an assistant professor of chemistry at Scripps, and his coworkers reported that by acidifying an alkaline solution of a cyclic octapeptide, they triggered stacking of the peptide hoops through hydrogen-bonding interactions (C&EN, Nov. 29,1993, page 8). The tubular structures formed have an internal diameter of ab...