| dc.description.abstract | There are many important biological functions in the living cells, such as membrane fusion. Biological functions are closely related to lipid packing. So, the development of a technique to determine the molecular packing density of a lipid bilayer is helpful in understanding lipid packing and modulating biological functions.
In the work, X-ray scattering technique is used to obtain the electron density profile of a lipid bilayer, which provides the information about the structure of a lipid bilayer. Then, the electron density profile is converted to the number density, which provides the information about the lipid packing density. In order to obtain more accurate structure of a lipid bilayer, the X-ray scattering data of oligolamellar vesicle and supported lipid bilayer are combined. In the work, we focus on how to obtain the number density of a lipid bilayer.
In the biological membrane, the most abundant lipids are phosphatidylcholine (PC) and phosphatidylethanolamine (PE). Besides, the most biologically relevant state of lipid bilayers is fully hydrated, fluid phase. Based on the above, dioleoyl-sn-glycero-3-phosphocholine (DOPC) and 1, 2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) are lipids which close to the actual biological system. The variations in DOPC and DOPE lipid composition affect the biological functions. Therefore, technique to determine the molecular packing density of a lipid bilayer is used to study the packing of DOPC/DOPE (0 – 50 mol% DOPE), from which the effect of lipid composition on the packing of lipid components is understood. | en_US |