Molecular structures of fluid phase phosphatidylglycerol bilayers as determined by small angle neutron and X-ray scattering.
Molecular structures of fluid phase phosphatidylglycerol bilayers as determined by small angle neutron and X-ray scattering.
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DOI：
10.1016/j.bbamem.2012.05.007
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发表时间：
2012-09
影响因子：
3.4
通讯作者：
Kucerka, Norbert
中科院分区：
文献类型：
--
作者：
Pan, Jianjun;Heberle, Frederick A.;Tristram-Nagle, Stephanie;Szymanski, Michelle;Koepfinger, Mary;Katsaras, John;Kucerka, Norbert
关键词：
我们已经确定了常用的磷脂酰甘油(PGs)在公认的生物相关流体相中的分子结构。这是通过同时分析小角中子和X射线散射数据，在测量的脂质体积的约束下完成的。我们报道了使用一维散射密度分布模型获得的双分子层参数的温度依赖关系，该模型来自分子动力学模拟-包括每脂类的面积、总的双分子层厚度以及其他双分子层内参数(例如碳氢化合物厚度)。研究发现，磷脂酰胆碱(PC)的脂质面积比其对应的磷脂酰胆碱(PC)大，这可能是由于即使在钠反离子存在的情况下，带电的PG头基之间也发生了排斥的静电相互作用。总体而言，PG和PC双层膜对温度和链长度的变化表现出类似的响应，但对链不饱和的响应不同。例如，与PC双层相比，PG脂中包含第一个双键导致每个脂质的面积和双层厚度的增量变化较小。然而，将饱和PG脂外推到无限长的链长时，其类脂面积与PC相似，这表明甘油-羰基骨架在影响脂-水界面中起着关键作用。
We have determined the molecular structures of commonly used phosphatidylglycerols (PGs) in the commonly accepted biologically relevant fluid phase. This was done by simultaneously analyzing small angle neutron and X-ray scattering data, with the constraint of measured lipid volumes. We report the temperature dependence of bilayer parameters obtained using the one-dimensional scattering density profile model – which was derived from molecular dynamics simulations – including the area per lipid, the overall bilayer thickness, as well as other intrabilayer parameters (e.g., hydrocarbon thickness). Lipid areas are found to be larger than their phosphatidylcholine (PC) counterparts, a result likely due to repulsive electrostatic interactions taking place between the charged PG headgroups even in the presence of sodium counterions. In general, PG and PC bilayers show a similar response to changes in temperature and chain length, but differ in their response to chain unsaturation. For example, compared to PC bilayers, the inclusion of a first double bond in PG lipids results in a smaller incremental change to the area per lipid and bilayer thickness. However, the extrapolated lipid area of saturated PG lipids to infinite chain length is found to be similar to that of PCs, an indication of the glycerol–carbonyl backbone's pivotal role in influencing the lipid–water interface.
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影响因子：
2.9
作者：
BLAUROCK, AE;MCINTOSH, TJ
通讯作者：
MCINTOSH, TJ
影响因子：
3.3
作者：
Anézo, C;de Vries, AH;Marrink, SJ
通讯作者：
Marrink, SJ
影响因子：
64.8
作者：
DEVRIJE, T;DESWART, RL;DEKRUIJFF, B
通讯作者：
DEKRUIJFF, B
影响因子：
3.8
作者：
Gordeliy, VI;Cherezov, VG;Teixeira, J
通讯作者：
Teixeira, J
影响因子：
3.4
作者：
Broemstrup, Torben;Reuter, Nathalie
通讯作者：
Reuter, Nathalie