6533b838fe1ef96bd12a4917
RESEARCH PRODUCT
Lipid carbonyl groups terminate the hydrogen bond network of membrane-bound water.
Mischa BonnEllen H. G. BackusYuki NagataMarialore SulpiziTatsuhiko OhtoCho-shuen Hsiehsubject
MembranesChemistryHydrogen bondInorganic chemistryWaterHydrogen BondingMolecular Dynamics SimulationLipidsMolecular dynamicsCrystallographychemistry.chemical_compoundMembranePulmonary surfactantPhosphatidylcholineMonolayerPhosphatidylcholinesGeneral Materials ScienceAmine gas treatingPhysical and Theoretical ChemistrySum frequency generation spectroscopydescription
We present a combined experimental sum-frequency generation (SFG) spectroscopy and ab initio molecular dynamics simulations study to clarify the structure and orientation of water at zwitterionic phosphatidylcholine (PC) lipid and amine N-oxide (AO) surfactant monolayers. Simulated O-H stretch SFG spectra of water show good agreement with the experimental data. The SFG response at the PC interface exhibits positive peaks, whereas both negative and positive bands are present for the similar zwitterionic AO interface. The positive peaks at the water/PC interface are attributed to water interacting with the lipid carbonyl groups, which act as efficient hydrogen bond acceptors. This allows the water hydrogen bond network to reach, with its (up-oriented) O-H groups, into the headgroup of the lipid, a mechanism not available for water underneath the AO surfactant. This highlights the role of the lipid carbonyl group in the interfacial water structure at the membrane interface, namely, stabilizing the water hydrogen bond network.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2015-11-02 | The journal of physical chemistry letters |