Triba Mohamed N, Devaux Philippe F, Warschawski Dror E
Unité Mixte de Recherche No. 7099, Centre National de la Recherche Scientifique, Institut de Biologie Physico-Chimique, Paris, France.
Biophys J. 2006 Aug 15;91(4):1357-67. doi: 10.1529/biophysj.106.085118. Epub 2006 May 26.
Most studies reported until now on the magnetically alignable system formed by the binary mixtures of long- and short-chain lipids were based on the mixture of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (D14PC) and 1,2-dihexanoyl-sn-glycero-3-phosphocholine (D6PC) lipids. We have recently shown that a large part of the phase diagrams of this lipid mixture could be understood by taking into account the partial miscibility between the long-chain lipids and the short-chain lipids when the sample was heated above the melting transition temperature (Tm) of the long-chain lipids. In this work, we show by modifying the chain length of either one of the two lipids that it is possible to control their miscibility and thus the intervals of temperature and composition where spontaneous alignment is observed in a magnetic field. By using 31P NMR, we demonstrate that the very special properties of such binary lipid mixtures are correlated with the propensity for short-chain lipids to diffuse into the bilayer regions. We also show that lipid mixtures with comparable properties can be formed with unsaturated lipids such as 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC).
迄今为止，大多数关于由长链和短链脂质二元混合物形成的可磁排列系统的研究都是基于1,2 - 二肉豆蔻酰 - sn - 甘油 - 3 - 磷酸胆碱（D14PC）和1,2 - 二己酰 - sn - 甘油 - 3 - 磷酸胆碱（D6PC）脂质的混合物。我们最近表明，当样品加热到高于长链脂质的熔点转变温度（Tm）时，考虑到长链脂质和短链脂质之间的部分互溶性，这种脂质混合物的大部分相图是可以理解的。在这项工作中，我们通过改变两种脂质中任一种的链长表明，有可能控制它们的互溶性，从而控制在磁场中观察到自发排列的温度和组成区间。通过使用³¹P NMR，我们证明了这种二元脂质混合物的非常特殊的性质与短链脂质扩散到双层区域的倾向相关。我们还表明，具有可比性质的脂质混合物可以由不饱和脂质如1 - 棕榈酰 - 2 - 油酰 - sn - 甘油 - 3 - 磷酸胆碱（POPC）形成。
