Labarca P, Wolff D, Soto U, Necochea C, Leighton F
J Membr Biol. 1986;94(3):285-91. doi: 10.1007/BF01869724.
Fusion of a highly purified fraction of rat liver peroxisomal membranes to planar lipid bilayers incorporates large, cation-selective voltage-dependent pores. The PK/PCl ratio of these pores, estimated in KCl gradients, is close to 4. The pores display several conductance states and spend most of the time open at voltages near 0 mV, closing at more positive and negative voltages. At voltages near 0 mV the most frequent open state has a conductance of 2.4 nS in 0.3 M KCl. At voltages more positive and more negative than 10 mV the most frequent open state displays a conductance of 1.2 nS in 0.3 M KCl. With these results pore diameters of 3 and 1.5 nm, respectively, can be estimated. We suggest that these pores might account for the unusually high permeability of peroxisomes to low molecular weight solutes. Fusion also incorporates a perfectly anion-selective, two-open states channel with conductances of 50 and 100 pS in 0.1 M KCl.
将高度纯化的大鼠肝脏过氧化物酶体膜组分融合到平面脂质双分子层中会形成大型的、阳离子选择性的电压依赖性孔道。在氯化钾梯度中估算，这些孔道的PK/PCl比值接近4。这些孔道呈现出几种电导状态，在接近0 mV的电压下大部分时间处于开放状态，在更正或更负的电压下关闭。在接近0 mV的电压下，在0.3 M氯化钾中最常见的开放状态电导为2.4 nS。在比10 mV更正和更负的电压下，在0.3 M氯化钾中最常见的开放状态电导为1.2 nS。根据这些结果，可分别估算出孔道直径为3纳米和l.5纳米。我们认为，这些孔道可能是过氧化物酶体对低分子量溶质具有异常高通透性的原因。融合还会形成一种完美的阴离子选择性、具有两种开放状态的通道，在0.1 M氯化钾中的电导分别为50和100 pS。
