Solid-state NMR structural determination of components in an ion channel switch biosensor

Abstract

High-resolution structural analysis of membrane proteins is difficult to achieve with the commonly used methods of structural biology, X-ray diffraction, and solution-state NMR spectroscopy. By combining solid-state N MR studies of membrane peptides in powder and oriented samples, with solution-state studies in detergent micelles, three dimensional molecular structures can be obtained. We have used solid-state NMR methods to study the antibiotic, gramicidin A (gA), a peptide that forms ion channels in bilayer lipid membranes (BLMs). Receptor groups have been linked to gA channels embedded in a BLM tethered to a gold electrode in an 'ion channel switch' biosensor. The receptor is attached to ..