A comparative study of interfacial environments in lipid nanodiscs and vesicles.
A comparative study of interfacial environments in lipid nanodiscs and vesicles.
复制标题
脂质纳米盘和囊泡界面环境的比较研究。
DOI：
10.1016/j.bpr.2022.100066
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Baiz,CarlosR
中科院分区：
文献类型：
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作者：
You,Xiao;Thakur,Naveen;Ray,ArkaPrabha;Eddy,MatthewT;Baiz,CarlosR
膜蛋白的构象和动力学是由膜的局部环境中发生的蛋白质-脂质相互作用驱动的。这些环境仍然具有挑战性，以准确地捕捉在结构和生物物理实验中使用双层。因此，有一个现实的细胞膜模拟物在体外研究的需求日益增加。脂质纳米盘为膜蛋白研究提供了优于囊泡的某些优势。纳米盘越来越多地用于膜蛋白的结构和光谱表征。尽管纳米盘的普遍使用，脂质的界面环境局限于一个10-nm直径的区域仍然相对不足的探索。在这里，我们使用超快二维红外光谱和温度依赖性的红外吸收测量的酯羰基比较不同的脂质组合物和大小的脂质纳米盘的界面氢键结构和动力学与100纳米囊泡。我们研究了脂质成分和纳米盘大小的影响。我们发现，纳米盘和囊泡共享很大程度上相似的脂-水氢键环境和界面动力学。H-键合的测量值的差异表明，在纳米盘中的H-键动力学调制的环状脂质和支架蛋白之间的相互作用。
Membrane protein conformations and dynamics are driven by the protein-lipid interactions occurring within the local environment of the membrane. These environments remain challenging to accurately capture in structural and biophysical experiments using bilayers. Consequently, there is an increasing need for realistic cell-membrane mimetics forin vitrostudies. Lipid nanodiscs provide certain advantages over vesicles for membrane protein studies. Nanodiscs are increasingly used for structural and spectroscopic characterization of membrane proteins. Despite the common use of nanodiscs, the interfacial environments of lipids confined to a ∼10-nm diameter area have remained relatively underexplored. Here, we use ultrafast two-dimensional infrared spectroscopy and temperature-dependent infrared absorption measurements of the ester carbonyls to compare the interfacial hydrogen bond structure and dynamics in lipid nanodiscs of varying lipid compositions and sizes with ∼100-nm vesicles. We examine the effects of lipid composition and nanodisc size. We found that nanodiscs and vesicles share largely similar lipid-water H-bond environments and interfacial dynamics. Differences in measured enthalpies of H-bonding suggest that H-bond dynamics in nanodiscs are modulated by the interaction between the annular lipids and the scaffold protein.