Na-23-Nmr Study of Ion-Transport across Vesicle Membranes Facilitated by Phenylalanine Analogs of Gramicidin
by Hinton, J. F.; Easton, P. L.; Newkirk, D. K.; Shungu, D. C.
The transport of Na+ ions across phosphatidylcholine/phosphatidylglycerol large unilamellar vesicle membranes facilitated by phenylalanine analogs of gramicidin A has been studied using Na-23-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.
- Journal
- Biochimica et Biophysica Acta-Biomembranes
- Volume
- 1146
- Issue
- 2
- Year
- 1993
- Start Page
- 191-196
- URL
- https://dx.doi.org/10.1016/0005-2736(93)90355-4
- ISBN/ISSN
- 0005-2736
- DOI
- 10.1016/0005-2736(93)90355-4