Properties of voltage-gated ion channels formed by syringomycin E in planar lipid bilayers.
Properties of voltage-gated ion channels formed by syringomycin E in planar lipid bilayers.
复制标题
平面脂质双层中丁香霉素 E 形成的电压门控离子通道的特性。
DOI：
10.1007/s002329900005
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
Brand,JG
中科院分区：
文献类型：
--
作者：
Feigin,AM;Takemoto,JY;Wangspa,R;Teeter,JH;Brand,JG
使用平面脂质双层技术，我们证明脂缩肽抗生素丁香霉素 E 形成弱阴离子选择性的电压敏感离子通道。由一侧掺杂丁香霉素 E (1-40 μg/ml) 的二油酰甘油磷脂酰丝氨酸制成的双层中通道的形成受到顺式正电压的极大影响。电压从正值变为负值会导致 (i) 单通道电导突然增加（增加速率取决于电压），同时 (ii) 这些通道关闭，宏观电导随时间呈指数下降。多通道稳态电导、单通道电导、在正电压下打开通道和在负电压下关闭通道的速率以及在电压符号反转后观察到的单通道电导的强烈电压依赖性表明，跨膜场的变化引起丁香霉素E通道的显着重排，包括充当电压传感器的带电基团的间距的变化。丁香霉素 E 诱导的电导随丁香霉素 E 浓度的六次方增加，表明通道形成需要至少六个单体。
Using the planar lipid bilayer technique we demonstrate that the lipodepsipeptide antibiotic, syringomycin E, forms voltage-sensitive ion channels of weak anion selectivity. The formation of channels in bilayers made from dioleoylglycerophosphatidylserine doped with syringomycin E at one side (1–40 μg/ml) was greatly affected bycis-positive voltage. A change of voltage from a positive to a negative value resulted in (i) an abrupt increase in the single channel conductance (the rate of increase was voltage dependent) simultaneous with (ii) a closing of these channels and an exponential decrease in macroscopic conductance over time. The strong voltage dependence of multichannel steady state conductance, the single channel conductance, the rate of opening of channels at positive voltages and closing them at negative voltages, as well as the observed abrupt increase of single channel conductance after voltage sign reversal suggest that the change of the transmembrane field induces a significant rearrangement of syringomycin E channels, including a change in the spacing of charged groups that function as voltage sensors. The conductance induced by syringomycin E increased with the sixth power of syringomycin E concentration suggesting that at least six monomers are required for channel formation.