Control of Solubilized State and Estimation of Molecular Organization of Membrane Proteins by the Use of Analogues of Sodium Dodecyl Sulfate

在生化研究领域，阴离子表面活性剂十二烷基硫酸钠（SDS）是常规使用的。我们关注SDS类似物的潜力，其一般结构可以描述为：n-C_<12>H_<25>(OCH_2CH_2)OSO^<3->X^+。结果发现：(1)在阳离子被Li、Tris、三乙醇胺和三异丙醇胺取代的类似物中，前者作为蛋白质变性剂的强度甚至大于SDS，后者作为蛋白质变性剂的破坏性远小于SDS，而后者的破坏性则远小于SDS，在上述序列上逐渐变弱；(2)表面活性剂系列可用于确定蛋白质特别是膜蛋白的分子组装的组织层次；(3)该系列成功应用的一个典型例子是类囊体叶绿素蛋白分解产物的分离，该系列的不同表面活性剂具有不同的电泳模式；(4)将m=2 ~ 8的类似物与m= 6或大于6的类似物进行比较，发现只有m= 6或大于6的类似物对膜蛋白具有高亲和力，因此在这种表面活性剂的存在下可以有效地分离膜蛋白；(5)在聚丙烯酰胺凝胶电泳中，发现一种易于获得的表面活性剂与上述活性剂相似，其分布与烷基链长（碳原子数约为13）和氧乙烯链长（约为m =8）有关，可以有效地分离（Na，K）- atp酶的亚基而不引起变性。

In the field of biochemical research,an anionic surfactant,sodium dodecyl sulfate(SDS),is routinely used.We have focused our attention on the potentiality of analogues of SDS of which general structure can be described as follows:n-C_<12>H_<25>(OCH_2CH_2)OSO^<3->X^+.It was found that:(1)among the analogues having their cations replaced by Li,Tris,triethanolammine and triisopropanolammine,the first was stronger even than SDS as protein denaturant,and the others were far less destructive than SDS as protein denaturant,and the others were far less destructive than SDSbecoming milder on the sequence mentioned above;(2)the series of surfactant could be used to determine the hierarchy of organization of molecular assemblies of proteins especially membrane proteins;(3)a typical example of the successful application of the series is the separation of the products of disassembly of thylakoid chlorophyllproteins in which different surfactant of the series giving different electrophoretic patterns;(4)analogues with m=2to8 were compared with to reveal that only those with m equal to or larger than 6 have high affinity to membrane proteins and thus allows efficient separation of mambrane prteins in the presence of such a surfactant;(5)a readily available surfactant similar to those described above with distribution with respect to both alkyl chain length (number of carbon atoms around 13) and oxyethylene chain length(around m =8)was found to be an efficient additive in polyacrylamide gel elctrophoresis for separation of the subunits of (Na,K)-ATPase without causing denaturation.