Transmembrane pH-driven Na+ permeability of fluorinated phospholipid-based membranes |
| |
Authors: | L Clary V Ravily C Santaella P Vierling |
| |
Affiliation: | Laboratoire de Chimie Bio-Organique, ESA 6001 CNRS, Université de Nice, Sophia-Antipolis, Faculté des Sciences, France. |
| |
Abstract: | The permeability to the H+/Na+ exchange of fluorinated phospholipid-based membranes has been evaluated by measuring the dissipation rate of a liposomal transmembrane pH gradient in the presence of Na+. The fluorinated liposomes are made from fluorocarbon/hydrocarbon or fluorocarbon/fluorocarbon double-chain ether-connected glycerophosphocholines or amido-connected phosphocholines deriving from diaminopropanol or serine. The fluorocarbon/hydrocarbon mixed-chain phospholipids, as compared to the fluorocarbon/fluorocarbon ones, form membranes that are substantially more able to maintain a transmembrane pH gradient in the presence of NA+ and display a lower Na+ permeability. However, these membranes are more permeable to the H+/Na/ exchange than conventional DSPC (1,2-distearoylphosphatidylcholine) ones. Our results indicate a detrimental impact of the membrane fluorination degree on H+/Na+ permeability: the lower the fluorination degree of the membrane, the lower its H+/Na+ permeability. Concerning structure/permeability relationships, it appears that the replacement of the ester connecting bond in their fluorinated phosphatidylcholine analogues for an ether or amide one lowers the transmembrane H+/Na+ exchange. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|