Referenced in: none

Automatically associated channels: Kv10.1

Title: 23Na-nuclear magnetic resonance investigation of gramicidin-induced ion transport through membranes under equilibrium conditions.

Authors: D C Buster, J F Hinton, F S Millett, D C Shungu

Journal, date & volume: Biophys. J., 1988 Feb , 53, 145-52

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/2449917

Abstract
A technique for investigating the gramicidin-facilitated transport of Na+ ions across lipid bilayers of large unilamellar vesicles under the condition of ionic equilibrium has been developed using a combination of heat incubation of the gramicidin with the vesicles and 23Na-nuclear magnetic resonance (NMR) spectroscopy. Isolation of the two 23Na-NMR signals from the intra- and extravesicular Na+ with the shift reagent, dysprosium (III) tripolyphosphate, allows the equilibrium flux of Na+ through the gramicidin channels to be detected and treated as a two-site exchange process. This study indicates that the transport of Na+ through gramicidin channels is second order with respect to the gramicidin concentration.