US chemists have found a new way to make highly functionalised peptide mimics using click chemistry.

Kent Kirshenbaum and colleagues at New York University are studying a group of peptide mimics known as "peptoids". These molecules could incorporate all the sophisticated biological activity of proteins, while avoiding the major restriction limiting peptide use in medicine, their vulnerability to degradation in the body.

Kirshenbaum has now pioneered a powerful new method for making peptoids, which allows bioactive groups to be selectively positioned along the molecule's backbone. The peptoids are synthesised on a solid support, with units added sequentially to the end of the chain. This approach means biologically active groups can be added at predetermined positions along the molecule.

The bioactive components are attached to the peptoid backbone by the copper-catalysed click chemistry reaction between an azide and an alkyne. These groups react with each other very efficiently, but don't react with any of the other functionality found in the rest of the molecule.

Kirshenbaum believes that the possibilities for biomimetic molecules like peptoids are extremely broad, from energy transduction to information storage and biosensors to molecular imaging agents.

James Mitchell Crow