Strenk L M, Westerman P W, Doane J W
Biophys J. 1985 Nov;48(5):765-73. doi: 10.1016/S0006-3495(85)83834-0.
Molecular and conformational ordering in aqueous multilamellar suspensions of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) have been examined by deuterium nuclear magnetic resonance (2H NMR) in the liquid crystalline (L alpha) phase. Motionally averaged quadrupolar splittings vQ from six sites in the vicinity of the glycerol backbone have been analyzed by a molecular frame and order matrix approach in which the usual assumption of a freely-rotating molecule is not invoked. By assuming a relatively rigid glycerol backbone region, the six vQ values are found to be consistent with a conformation of the glycerol backbone that is almost identical to that of one of the two structures in crystalline DMPC dihydrate (Pearson, R. H., and I. Pascher, 1979, Nature (Lond.) 281: 499-501). The orientation of the most-ordered axis of the DMPC molecule is found to be tilted at an angle of 27 +/- 2 degrees with respect to the long axis of the sn-1 chain in its extended all trans conformation. The ordering of the most ordered molecular axis with respect to the bilayer normal is expressed by an order parameter of Szz approximately equal to 0.6 +/- 0.1, consistent with values in analogous thermotropic liquid crystals.
通过氘核磁共振（2H NMR）在液晶（Lα）相中研究了1,2 - 二肉豆蔻酰 - sn - 甘油 - 3 - 磷酸胆碱（DMPC）水相多层悬浮液中的分子和构象有序性。采用分子框架和序矩阵方法分析了甘油主链附近六个位点的运动平均四极分裂vQ，其中未采用分子自由旋转的通常假设。通过假设甘油主链区域相对刚性，发现六个vQ值与甘油主链的构象一致，该构象几乎与结晶DMPC二水合物中两种结构之一相同（Pearson, R. H., and I. Pascher, 1979, Nature (Lond.) 281: 499 - 501）。发现DMPC分子最有序轴的取向相对于其伸展的全反式构象中的sn - 1链的长轴倾斜27±2度。最有序分子轴相对于双层法线的有序性由序参数Szz约等于0.6±0.1表示，这与类似热致液晶中的值一致。
