OCTYL GLUCOSIDE PROMOTES INCORPORATION OF CHANNELS INTO NEUTRAL PLANAR PHOSPHOLIPID-BILAYERS - STUDIES WITH COLICIN IA
OCTYL GLUCOSIDE PROMOTES INCORPORATION OF CHANNELS INTO NEUTRAL PLANAR PHOSPHOLIPID-BILAYERS - STUDIES WITH COLICIN IA
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DOI：
10.1016/0005-2736(86)90015-5
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发表时间：
1986-03-27
期刊：
影响因子：
--
通讯作者：
COHEN, FS
中科院分区：
文献类型：
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作者：
BULLOCK, JO;COHEN, FS
大肠杆菌素Ia在含有酸性磷脂的平面磷脂双分子层中形成电压依赖性通道。添加中性去污剂辛基葡糖苷，其浓度比临界胶束浓度（CMC）低三个数量级时，可极大地增加通道形成活性，而不改变通道本身的特性。此外，辛基葡糖苷促进大肠杆菌素Ia在仅含中性脂质的膜中形成通道，从而能够研究不受负表面电荷影响而扭曲的通道的生物物理特性。在中性膜中，宏观电流随时间呈双相变化，快速成分是电压依赖性的，而慢速成分与电压无关。在1M氯化钠中，单通道电导为31皮西门子，通道对阴离子有轻微选择性。讨论了去污剂促进通道形成的机制。
Colicin Ia forms voltage-dependent channels in planar phospholipid bilayers containing acidic phospholipids. Addition of the neutral detergent octyl glucoside, at concentrations three orders of magnitude below its critical micelle concentration (CMC), greatly increases channel-forming activity without altering the properties of the channels themselves. Further, octyl glucoside promotes formation of channels by colicin Ia in membranes containing only neutral lipids, making it possible to study the biophysical properties of the channel undistorted by the effects of negative surface charge. In neutral membranes, the macroscopic currents are biphasic with time, the fast component is voltage-dependent and the slow component voltage-independent. The single-channel conductance in 1 M NaCl is 31 pS and the channel is slightly anion selective. The mechanism by which the detergent facilitates channel formation is discussed.