Location of TEMPO-PC in Lipid Bilayers: Implications for Fluorescence Quenching.
Location of TEMPO-PC in Lipid Bilayers: Implications for Fluorescence Quenching.
复制标题
TEMPO-PC 在脂质双层中的位置：对荧光猝灭的影响。
DOI：
10.1007/s00232-019-00094-1
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发表时间：
2020
期刊：
影响因子：
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通讯作者：
Ladokhin,AlexeyS
中科院分区：
文献类型：
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作者：
Kyrychenko,Alexander;Ladokhin,AlexeyS
描述脂质自旋探针在双层膜中的行为对于正确解释EPR和荧光研究蛋白质-膜相互作用的结果具有重要意义。了解克里思自旋探针在TEMPO-PC中与脂质头基连接的浸没深度对于确定与蛋白质和肽连接的荧光探针的横向位置至关重要。TEMPO-PC中克里思部分的双层渗透问题最近在界面溶剂化的两项研究中变得突出（Cheng等人，Biophys J 109：330-339，2015; Lee等人，Biophys J 111：2481-2491，2016）。在这里，我们重新检查的参数克里思渗透使用交叉验证MD模拟和深度依赖性荧光淬灭实验，这证实了克里思在TEMPO-PC渗透低于磷酸基团的水平。荧光猝灭的正确分析需要使用磷酸基团水平以下的克里思位置;不这样做将导致在确定膜蛋白上标记位点的渗透时产生大量系统误差。
AbstractThe characterization of the behavior of lipid-attached spin probes in a bilayer is of fundamental importance for correct interpretation of the results of both EPR and fluorescence studies of protein-membrane interactions. The knowledge of the immersion depth of TEMPO spin probe attached to lipid headgroup in TEMPO-PC is critical for the determination of the transverse location of fluorescence probes attached to proteins and peptides. The question of bilayer penetration of TEMPO moiety in TEMPO-PC has recently came into prominence in two studies of interfacial solvation (Cheng et al. in Biophys J 109:330–339, 2015; Lee et al. in Biophys J 111:2481–2491, 2016). Here, we re-examine the arguments on TEMPO penetration using the cross-validation of MD simulations and depth-dependent fluorescence-quenching experiments, which confirms that TEMPO in TEMPO-PC penetrates below the level of phosphate groups. The proper analysis of fluorescence quenching requires the use of Tempo position below the level of phosphate groups; and failure to do so will result in substantial systematic errors in determining the penetration of the labeled site on a membrane protein.Graphic Abstract