New insights into the structure and hydration of a stratum corneum lipid model membrane by neutron diffraction
New insights into the structure and hydration of a stratum corneum lipid model membrane by neutron diffraction
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通过中子衍射对角质层脂质模型膜的结构和水合作用的新见解
DOI：
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
R. Neubert
中科院分区：
文献类型：
--
作者：
M. Kiselev;N. Ryabova;A. Balagurov;S. Dante;T. Hauß;J. Zbytovská;S. Wartewig;R. Neubert
通过中子衍射对由 N-(α-羟基十八酰基)-植物鞘氨醇 (CER6)/胆固醇 (Ch)/棕榈酸 (PA)/胆固醇硫酸盐 (ChS) 组成的角质层 (SC) 脂质模型膜的结构和水化进行了表征。根据测量的衍射峰强度计算穿过 SC 脂质模型膜的中子散射长度密度。确定了内部膜结构和跨双层的水分布函数。膜间空间的低水合作用是 SC 脂质模型膜的主要特征。完全水合时，SC 脂质模型膜中水层的厚度约为 1 Å。对于 55% CER6/25% Ch/15% PA/5% ChS 的组合物，在部分脱水状态（60% 湿度）和 32°C 下，层状重复距离和膜厚度具有相同的值 45.6 Å。膜的疏水区域厚度为 31.2 Å。 Ch含量的减少增加了膜的厚度。水通过 SC 脂质模型多层膜的扩散相对于通过磷脂膜的扩散是相当慢的过程。在过量的水中，膜水合遵循指数规律，两个特征时间分别为 93 分钟和 44 分钟。在 81°C 和 97% 湿度下，膜分离成两相，重复距离分别为 45.8 和 40.5 Å。讨论了干燥和水合多层中 CER6 分子的可能构象。
The structure and hydration of a stratum corneum (SC) lipid model membrane composed of N-(α-hydroxyoctadecanoyl)-phytosphingosine (CER6)/cholesterol (Ch)/palmitic acid (PA)/cholesterol sulfate (ChS) were characterized by neutron diffraction. The neutron scattering length density across the SC lipid model membrane was calculated from measured diffraction peak intensities. The internal membrane structure and water distribution function across the bilayer were determined. The low hydration of the intermembrane space is a major feature of the SC lipid model membrane. The thickness of the water layer in the SC lipid model membrane is about 1 Å at full hydration. For the composition 55% CER6/25% Ch/15% PA/5% ChS, in a partly dehydrated state (60% humidity) and at 32°C, the lamellar repeat distance and the membrane thickness have the same value of 45.6 Å . The hydrophobic region of the membrane has a thickness of 31.2 Å . A decrease of the Ch content increases the membrane thickness. The water diffusion through the SC lipid model multilamellar membrane is a considerably slow process relative to that through phospholipid membranes. In excess water, the membrane hydration follows an exponential law with two characteristic times of 93 and 44 min. At 81°C and 97% humidity, the membrane separates into two phases with repeat distances of 45.8 and 40.5 Å . Possible conformations of CER6 molecules in the dry and hydrated multilayers are discussed.
影响因子：
2.9
作者：
WHITE, SH;MIREJOVSKY, D;KING, GI
通讯作者：
KING, GI
影响因子：
3.4
作者：
M. Wiener;S. White
通讯作者：
M. Wiener;S. White
影响因子：
3.4
作者：
Hristova, K;White, SH
通讯作者：
White, SH