Fluorescence microscopy of the pressure-dependent structure of lipid bilayers suspended across conical nanopores.
Fluorescence microscopy of the pressure-dependent structure of lipid bilayers suspended across conical nanopores.
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悬浮在锥形纳米孔上的脂质双层的压力依赖性结构的荧光显微镜。
DOI：
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发表时间：
2011
影响因子：
15
通讯作者：
H. White
中科院分区：
文献类型：
--
作者：
Anna E. P. Schibel;Emily C. Heider;J. Harris;H. White
由于悬浮在纳米孔孔上的脂质双分子层具有很高的固有稳定性，以及玻璃和熔融石英具有良好的电学性能，玻璃和熔融石英纳米孔膜含有单个锥形孔，是脂质双分子层离子通道记录的有前途的固体支撑。荧光显微镜用于研究悬浮脂质双分子层的结构，作为施加在熔融石英纳米孔膜上的压力的函数。当从纳米孔内部相对于外部体溶液施加正压穿过双分子层时，观察到双分子层中有效离子通道（例如α-溶血素（α-HL）和gramicidin）的插入或重建；相反，反转施加压力的方向会导致所有通道活性丧失，尽管双分子层保持完整。通过将尼罗红染料掺杂到悬浮的1,2-二phytanyl -sn-glycero-3-phosphocholine双层中，同时记录α-HL通道的活性，研究了双层结构对压力的依赖性。荧光图像表明，正压导致双分子层小叶的压缩和双分子层曲率的增加，使其适合离子通道的形成和活性。在负压下，荧光图像与脂质小叶的分离一致，导致观察到的离子通道活性损失。荧光数据表明，压力诱导的双层结构的变化是可逆的，这与分别施加正负压反复开关离子通道活性的能力是一致的。
Glass and fused-quartz nanopore membranes containing a single conically shaped pore are promising solid supports for lipid bilayer ion-channel recordings due to the high inherent stability of lipid bilayers suspended across the nanopore orifice, as well as the favorable electrical properties of glass and fused quartz. Fluorescence microscopy is used here to investigate the structure of the suspended lipid bilayer as a function of the pressure applied across a fused-quartz nanopore membrane. When a positive pressure is applied across the bilayer, from the nanopore interior relative to the exterior bulk solution, insertion or reconstitution of operative ion channels (e.g., α-hemolysin (α-HL) and gramicidin) in the bilayer is observed; conversely, reversing the direction of the applied pressure results in loss of all channel activity, although the bilayer remains intact. The dependence of the bilayer structure on pressure was explored by imaging the fluorescence intensity from Nile red dye doped into suspended 1,2-diphytanoyl-sn-glycero-3-phosphocholine bilayers, while simultaneously recording the activity of an α-HL channel. The fluorescence images suggest that a positive pressure results in compression of the bilayer leaflets and an increase in the bilayer curvature, making it suitable for ion-channel formation and activity. At negative pressure, the fluorescence images are consistent with separation of the lipid leaflets, resulting in the observed loss of the ion-channel activity. The fluorescence data indicate that the changes in the pressure-induced bilayer structure are reversible, consistent with the ability to repeatedly switch the ion-channel activity on and off by applying positive and negative pressures, respectively.
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影响因子：
15
作者：
Schibel AE;An N;Jin Q;Fleming AM;Burrows CJ;White HS
通讯作者：
White HS
影响因子：
3.4
作者：
Akeson, M;Branton, D;Deamer, DW
通讯作者：
Deamer, DW
DOI：
10.1073/pnas.96.15.8461
发表时间：
1999-07-20
影响因子：
11.1
作者：
Korlach, J;Schwille, P;Feigenson, GW
通讯作者：
Feigenson, GW
影响因子：
15
作者：
Lathrop, Daniel K.;Ervin, Eric N.;Barrall, Geoffrey A.;Keehan, Michael G.;Kawano, Ryuji;Krupka, Michael A.;White, Henry S.;Hibbs, Andrew H.
通讯作者：
Hibbs, Andrew H.