23Na-NMR study of ion transport across vesicle membranes facilitated by phenylalanine analogs of gramicidin.

Publication Type	Academic Article
Authors	Hinton J, Easton P, Newkirk D, Shungu D
Journal	Biochim Biophys Acta
Volume	1146
Issue	2
Pagination	191-6
Date Published	03/14/1993
ISSN	0006-3002
Keywords	Gramicidin, Phenylalanine, Sodium
Abstract	The transport of Na+ ions across phosphatidylcholine/phosphatidylglycerol large unilamellar vesicle membranes facilitated by phenylalanine analogs of gramicidin A has been studied using 23Na-NMR spectroscopy. The four analogs studied were Phe9-, Phe11-, Phe13-and Phe15-gramicidin A. These analogs were found to transport Na+ ions in the following order Phe15 > Phe13 > Phe11 > Phe9. The entropy and enthalpy of activation for the transport of Na+ ions were determined for each analog. A correlation is made between the activation enthalpies and the single channel conductance values of the analogs.
DOI	10.1016/0005-2736(93)90355-4
PubMed ID	7680900