Action of the multifunctional peptide BP100 on native biomembranes examined by solid-state NMR
Action of the multifunctional peptide BP100 on native biomembranes examined by solid-state NMR
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DOI：
10.1007/s10858-015-9897-8
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发表时间：
2015-01
影响因子：
2.7
通讯作者：
J. Misiewicz;S. Afonin;S. Grage;J. Berg;E. Strandberg;P. Wadhwani;A. Ulrich
中科院分区：
文献类型：
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作者：
J. Misiewicz;S. Afonin;S. Grage;J. Berg;E. Strandberg;P. Wadhwani;A. Ulrich
膜组成是调控抗菌肽在体内的破坏活性和细胞穿透肽无渗漏渗透的关键因素。因此，模型膜的选择是核磁共振研究的一个关键方面，应尽可能地反映生物状况。在这里，我们利用多核固体核磁共振方法探索了短多功能肽BP100的结构和动力学。在不同净电荷、流动性和厚度的合成脂质双层以及原核和真核细胞的天然生物膜中，研究了这种11个氨基酸肽的膜取向和迁移性。19F-NMR提供了高灵敏度和缺乏自然丰度背景，即使在黄体微球菌的原生质体膜和红细胞鬼影中观察标记肽也是必要的。6个选择性19f标记的BP100类似物在所有的宏观取向膜体系中都具有非常相似的光谱，在环境温度和完全水化的准自然条件下进行了研究。这种相似性表明BP100在不同生物膜和模型膜中具有相同的表面结合螺旋结构和高迁移率，与系统的电荷、厚度或胆固醇含量无关。磷脂组分的31P-NMR没有显示任何双层扰动，因此可以排除环形虫孔的形成或胶束化作为其抗菌或细胞穿透作用的机制。然而，对酰基链序参数谱的2H-NMR分析表明，BP100导致了相当大的膜变薄，从而导致了局部不稳定。
Membrane composition is a key factor that regulates the destructive activity of antimicrobial peptides and the non-leaky permeation of cell penetrating peptides in vivo. Hence, the choice of model membrane is a crucial aspect in NMR studies and should reflect the biological situation as closely as possible. Here, we explore the structure and dynamics of the short multifunctional peptide BP100 using a multinuclear solid-state NMR approach. The membrane alignment and mobility of this 11 amino acid peptide was studied in various synthetic lipid bilayers with different net charge, fluidity, and thickness, as well as in native biomembranes harvested from prokaryotic and eukaryotic cells.19F-NMR provided the high sensitivity and lack of natural abundance background that are necessary to observe a labelled peptide even in protoplast membranes fromMicrococcus luteusand in erythrocyte ghosts. Six selectively19F-labeled BP100 analogues gave remarkably similar spectra in all of the macroscopically oriented membrane systems, which were studied under quasi-native conditions of ambient temperature and full hydration. This similarity suggests that BP100 has the same surface-bound helical structure and high mobility in the different biomembranes and model membranes alike, independent of charge, thickness or cholesterol content of the system.31P-NMR spectra of the phospholipid components did not indicate any bilayer perturbation, so the formation of toroidal wormholes or micellarization can be excluded as a mechanism of its antimicrobial or cell penetrating action. However,2H-NMR analysis of the acyl chain order parameter profiles showed that BP100 leads to considerable membrane thinning and thereby local destabilization.