Application of the Magnetization-Inversion-Transfer Technique to the Transport of Li-7(+), Na-23(+), and K-39(+) Ions through the Gramicidin Channel and the M2-Delta Transmembrane Domain of the Nicotinic Acetylcholine-Receptor

by Hinton, James F.; Newkirk, Donald Keith; Fletcher, Terry Grant; Shungu, Dikoma C.

The magnetization-inversion-transfer NMR technique has been used to determine the activation enthalpy (Delta H-double dagger) for the transport of the Li-7(+), Na-23(+), and K-39(+) ions through the gramicidin channel incorporated into vesicle membranes. The activation enthalpy obtained for the overall transport of the monovalent cations was found to be in agreement with the selectivity order and single-channel ion conductance values. Furthermore, the magnetizatian-inversion-transfer technique was also found to be applicable to the channel formed from a synthetic peptide having the same amino acid sequence as the M2 delta transmembrane segment of the nicotinic acetylcholine receptor. (C) 1994 Academic Press, Inc.

Journal
Journal of Magnetic Resonance Series B
Volume
105
Issue
1
Year
1994
Start Page
11
ISBN/ISSN
1096-0856; 1064-1866
DOI
10.1006/jmrb.1994.1093