Spector M S, Easwaran K R, Jyothi G, Selinger J V, Singh A, Schnur J M
Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, DC 20375, USA.
Proc Natl Acad Sci U S A. 1996 Nov 12;93(23):12943-6. doi: 10.1073/pnas.93.23.12943.
We report on spectroscopic studies of the chiral structure in phospholipid tubules formed in mixtures of alcohol and water. Synthetic phospholipids containing diacetylenic moieties in the acyl chains self-assemble into hollow, cylindrical tubules in appropriate conditions. Circular dichroism provides a direct measure of chirality of the molecular structure. We find that the CD spectra of tubules formed in mixtures of alcohol and water depends strongly on the alcohol used and the lipid concentration. The relative spectral intensity of different circular dichroism bands correlates with the number of bilayers observed using microscopy. The results provide experimental evidence that tubule formation is based on chiral packing of the lipid molecules and that interbilayer interactions are important to the tubule structure.
我们报道了对在酒精和水的混合物中形成的磷脂小管中手性结构的光谱研究。在酰基链中含有二乙炔基部分的合成磷脂在适当条件下会自组装成中空的圆柱形小管。圆二色性提供了分子结构手性的直接测量方法。我们发现，在酒精和水的混合物中形成的小管的圆二色光谱强烈依赖于所使用的酒精和脂质浓度。不同圆二色带的相对光谱强度与使用显微镜观察到的双层数量相关。这些结果提供了实验证据，表明小管的形成基于脂质分子的手性堆积，并且双层间相互作用对小管结构很重要。
