Interfacial Dynamics in Lipid Membranes: The Effects of Headgroup Structures
Interfacial Dynamics in Lipid Membranes: The Effects of Headgroup Structures
复制标题
脂质膜中的界面动力学：头基结构的影响
DOI：
10.1021/acs.jpcb.0c08755
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Baiz, Carlos R.
中科院分区：
文献类型：
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作者：
Valentine, Mason L.;Waterland, Maya K.;Fathizadeh, Arman;Elber, Ron;Baiz, Carlos R.
磷脂膜支持基本的生物化学过程，但由于其组成和结构的异质性，仍然难以表征。生物膜中最常见的两种磷脂头基结构是磷脂酰胆碱（PC）和磷脂酰乙醇胺（PE），但PC和PE脂质之间的相互作用仍有待研究。在这项研究中，我们应用超快二维红外（2D IR）光谱定量头基PC/PE脂质混合物的界面动力学的影响。实验解释通过分子动力学模拟使用分子动力学与炼金术步骤（MDAS）算法增强采样。实验结果表明，PE含量减少氢键形成的酯羰基位置附近的脂质膜的疏水核心作为一个结果，增加堆积密度。所观察到的脱水与界面区域内更快的分子动力学有关。
Phospholipid membranes support essential biochemical processes, yet remain difficult to characterize due to their compositional and structural heterogeneity. The two most common phospholipid headgroup structures in biological membranes are phosphatidylcholine (PC) and phosphatidylethanolamine (PE), but interactions between PC and PE lipids remain underexplored. In this study, we apply ultrafast two-dimensional infrared (2D IR) spectroscopy to quantify the headgroup effects on interfacial dynamics in PC/PE lipid mixtures. Experiments are interpreted through molecular dynamics simulations using the molecular dynamics with alchemical step (MDAS) algorithm for enhanced sampling. Experimental results indicate that the PE content decreases H-bond formation at the ester carbonyl positions near the lipid membrane’s hydrophobic core as a result of increased packing density. The observed dehydration is linked to faster molecular dynamics within the interfacial region.