Samanta Soumya, Stiban Johnny, Maugel Timothy K, Colombini Marco
Department of Biology, University of Maryland, College Park, MD 20742, USA.
Biochim Biophys Acta. 2011 Apr;1808(4):1196-201. doi: 10.1016/j.bbamem.2011.01.007. Epub 2011 Jan 19.
Functional studies have shown that the sphingolipid ceramide, self-assembles in phospholipid membranes to form large channels capable of allowing proteins to cross the membrane. Here these channels are visualized by negative stain transmission electron microscopy. The images contain features consistent with stain-filled pores having a roughly circular profile. There is no indication of tilt, and the results are consistent with the formation of right cylinders. The sizes of the pores range from 5 to 40nm in diameter with an asymmetric distribution indicating no apparent upper size limit. The size distribution matches well with the distribution of sizes calculated from electrophysiological measurements.
功能研究表明，鞘脂神经酰胺在磷脂膜中自组装形成大通道，能够使蛋白质穿过膜。在这里，这些通道通过负染透射电子显微镜观察到。图像包含与大致呈圆形轮廓的充满染色剂的孔一致的特征。没有倾斜迹象，结果与直圆柱体的形成一致。孔的直径范围为5至40纳米，不对称分布表明没有明显的尺寸上限。尺寸分布与根据电生理测量计算出的尺寸分布非常匹配。
