Harb Frédéric, Tinland Bernard
Aix-Marseille Université, CINaM, CNRS, Marseille, France.
Electrophoresis. 2013 Nov;34(20-21):3054-63. doi: 10.1002/elps.201300202. Epub 2013 Oct 1.
Proteome analysis involves separating proteins as a preliminary step toward their characterization. This paper reports on the translational migration of a model transmembrane protein (α-hemolysin) in supported n-bilayers (n, the number of bilayers, varies from 1 to around 500 bilayers) when an electric field parallel to the membrane plane is applied. The migration changes in direction as the charge on the protein changes its sign. Its electrophoretic mobility is shown to depend on size and charge. The electrophoretic mobility varies as 1/R(2), with R the equivalent geometric radius of the embedded part of the protein. Measuring mobilities at differing pH in our system enables us to determine the pI and the charge of the protein. Establishing all these variations points to the feasibility of electrophoretic transport of a charged object in this medium and is a first step toward electrophoretic separation of membrane proteins in n-bilayer systems.
蛋白质组分析包括分离蛋白质，这是对其进行表征的初步步骤。本文报道了在施加平行于膜平面的电场时，模型跨膜蛋白（α-溶血素）在支撑的n层双分子层（n，双分子层的数量从1到约500个双分子层不等）中的平移迁移。当蛋白质上的电荷改变其符号时，迁移方向会发生变化。其电泳迁移率显示取决于大小和电荷。电泳迁移率随1/R(2)变化，其中R是蛋白质嵌入部分的等效几何半径。在我们的系统中测量不同pH值下的迁移率使我们能够确定蛋白质的pI和电荷。确定所有这些变化表明带电物体在这种介质中进行电泳传输是可行的，并且是在n层双分子层系统中对膜蛋白进行电泳分离的第一步。
