Influence of the curvature on the water structure in the headgroup region of phospholipid bilayer studied by the solvent relaxation technique
Language English Country Ireland Media print-electronic
Document type Journal Article, Research Support, Non-U.S. Gov't
PubMed
15921979
DOI
10.1016/j.chemphyslip.2005.03.003
PII: S0009-3084(05)00060-5
Knihovny.cz E-resources
- MeSH
- Spectrometry, Fluorescence MeSH
- Phosphatidylcholines MeSH
- Phospholipids chemistry MeSH
- Lipid Bilayers chemistry MeSH
- Liposomes chemistry MeSH
- Molecular Probes MeSH
- Water chemistry MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- 1,2-oleoylphosphatidylcholine MeSH Browser
- Phosphatidylcholines MeSH
- Phospholipids MeSH
- Lipid Bilayers MeSH
- Liposomes MeSH
- Molecular Probes MeSH
- Water MeSH
Solvent relaxation (SR) in 1,2-dioleoyl-palmitoyl-sn-glycero-3-phosphocholine (DOPC) unilamellar vesicles of different size was probed by 6-hexadecanoyl-2-(((2-(trimethylammonium)ethyl)methyl)amino)naphthalene chloride (Patman), 6-propionyl-2-dimethylaminonaphthalene (Prodan) and 4-[(n-dodecylthio)methyl]-7-(N,N-dimethylamino)-coumarin (DTMAC). Patman probes the amount and mobility of the bound water molecules located at the carbonyl region of the bilayer. Membrane curvature significantly accelerates the solvent relaxation process, but does not influence the total Stokes shift, showing that membrane curvature increases the mobility, without affecting the amount of water molecules present in the headgroup region. This pattern was also verified for other phosphatidylcholines. Prodan is located in the phosphate region of the bilayer and probes a more polar, mobile and heterogeneous environment than Patman. The influence of membrane curvature on SR probed by Prodan is similar, however, less pronounced compared to Patman. DTMAC (first time used in SR) shows a broad distribution of locations along the z-axis. A substantial amount of the coumarin chromophores face bulk water. No effect of curvature on SR probed by DTMAC is detectable.
References provided by Crossref.org
