Swelling of phospholipids by monovalent salt Published, JLR Papers in Press, November 2, 2005.
Swelling of phospholipids by monovalent salt Published, JLR Papers in Press, November 2, 2005.
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一价盐引起的磷脂溶胀发表于 JLR Papers in Press，2005 年 11 月 2 日。
DOI：
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发表时间：
2006
影响因子：
6.5
通讯作者：
V. Parsegian
中科院分区：
文献类型：
--
作者：
H. Petrache;S. Tristram;D. Harries;N. Kučerka;J. Nagle;V. Parsegian
膜-水界面上的离子-脂质相互作用对膜融合和分泌等生物过程至关重要，但仍存在许多未解之谜。使用重建的磷脂酰胆碱膜，我们在这里证实，多层囊泡在盐溶液中膨胀，直接表明盐修改相邻膜之间的相互作用。通过改变样品的历史，并通过与含离子载体的双层的数据进行比较，我们消除了溶胀是平衡伪影的可能性。虽然吸引力和排斥力可以修改盐，我们的实验表明，膨胀主要是由削弱的货车德瓦尔斯吸引力。为了分离盐对货车范德华相互作用的影响，我们专注于高盐浓度，在此浓度下，任何可能的静电相互作用都被筛选。通过X射线衍射数据的分析，我们表明，盐不会改变膜的结构或弯曲刚度，消除了排斥波动力与盐的变化的可能性。通过测量施加渗透应力的双层间分离的变化，我们已经确定，使用双层相互作用的标准范例，即1 M浓度的KBr或KCl降低了50%的货车范德华强度。通过削弱货车范德华吸引力，盐增加了膜接触的能量屏障，可能影响细胞通讯和生物信号。
Critical to biological processes such as membrane fusion and secretion, ion-lipid interactions at the membrane-water interface still raise many unanswered questions. Using reconstituted phosphatidylcholine membranes, we confirm here that multilamellar vesicles swell in salt solutions, a direct indication that salt modifies the interactions between neighboring membranes. By varying sample histories, and by comparing with data from ion carrier-containing bilayers, we eliminate the possibility that swelling is an equilibration artifact. Although both attractive and repulsive forces could be modified by salt, we show experimentally that swelling is driven primarily by weakening of the van der Waals attraction. To isolate the effect of salt on van der Waals interactions, we focus on high salt concentrations at which any possible electrostatic interactions are screened. By analysis of X-ray diffraction data, we show that salt does not alter membrane structure or bending rigidity, eliminating the possibility that repulsive fluctuation forces change with salt. By measuring changes in interbilayer separation with applied osmotic stress, we have determined, using the standard paradigm for bilayer interactions, that 1 M concentrations of KBr or KCl decrease the van der Waals strength by 50%. By weakening van der Waals attractions, salt increases energy barriers to membrane contact, possibly affecting cellular communication and biological signaling.
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影响因子：
2.9
作者：
GRUNER, SM;LENK, RP;OSTRO, MJ
通讯作者：
OSTRO, MJ
影响因子：
3.4
作者：
Petrache, HI;Dodd, SW;Brown, MF
通讯作者：
Brown, MF
影响因子：
2.4
作者：
Lyatskaya, Y;Liu, YF;Nagle, JF
通讯作者：
Nagle, JF
影响因子：
3.4
作者：
PEITZSCH, RM;EISENBERG, M;MCLAUGHLIN, S
通讯作者：
MCLAUGHLIN, S
DOI：
10.1016/0005-2736(88)90153-8
发表时间：
1988-02
期刊：
Biochimica et biophysica acta
影响因子：
--
作者：
M. Wiener;S. Tristram-Nagle;D.Alan Wilkinson;L. E. Campbell;J. F. Nagle
通讯作者：
M. Wiener;S. Tristram-Nagle;D.Alan Wilkinson;L. E. Campbell;J. F. Nagle