Gramicidin single-channel properties show no solvent-history dependence.
Gramicidin single-channel properties show no solvent-history dependence.
复制标题
短杆菌肽的单通道特性没有显示出溶剂历史依赖性。
DOI：
10.1016/s0006-3495(90)82567-4
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发表时间：
1990
影响因子：
3.4
通讯作者：
Andersen,OS
中科院分区：
文献类型：
--
作者：
Sawyer,DB;Koeppe2nd,RE;Andersen,OS
膜结合短杆菌肽的结构可取决于它们在膜掺入之前溶解于其中的溶剂（LoGrasso，P. V.，F. Moll和T. A.穿越1988年Biophys. J. 54：259-267; Killian，J. A.，K.联合Prasad，D. Hains和D. W.呃。1988.生物化学。27：4848-4855）。因此，肽的溶剂历史可能会影响短杆菌肽通道的功能特性（同前）。我们测试了这一建议，通过检查的属性（电导率，电导分散性，和平均持续时间）的通道形成的[Val 1]短杆菌肽A已溶解在8种不同的溶剂。将肽掺入脂质双层中，或者通过加入水相（随后吸附到膜上），或者通过与成膜磷脂共溶解。当肽与磷脂共溶解时，通道特性不随所用溶剂而变化。当肽溶解在氯仿，苯，或三氟乙醇，并通过水相添加时，通道特性不同于那些发现当gramidicin溶解在甲醇，乙醇，二氧六环，二甲亚砜，或乙酸乙酯。通过将前三种溶剂添加到水相中来再现用前三种溶剂观察到的变化，因此是由于这些溶剂分配到膜中并改变通道行为的能力。
The structure of membrane-associated gramicidins can depend on the solvent in which they were dissolved prior to membrane incorporation (LoGrasso, P. V., F. Moll, and T. A. Cross 1988. Biophys. J. 54:259–267; Killian, J. A., K. U. Prasad, D. Hains, and D. W. Urry. 1988. Biochemistry. 27:4848–4855). The peptide's solvent history might thus affect the functional characteristics of gramicidin channels (op. cit.). We tested this proposal by examining the properties (conductance, conductance dispersity, and average duration) of channels formed by [Val1]gramicidin A that had been dissolved in eight different solvents. The peptide was incorporated into lipid bilayers either by addition to the aqueous phase (and subsequent adsorption to the membrane) or by cosolubilization with the membrane-forming phospholipid. When the peptide was cosolubilized with the phospholipid, the channel properties did not vary with the solvent used. When the peptide was dissolved in chloroform, benzene, or trifluoroethanol and added through the aqueous phase, the channel properties differed from those found when gramidicin was dissolved in methanol, ethanol, dioxane, dimethylsulfoxide, or ethylacetate. The changes observed with the former three solvents were reproduced by adding them to the aqueous phase, and are therefore due to the ability of these solvents to partition into the membrane and alter the channels' behavior.