Quasi-elastic neutron scattering study of the effects of metal cations on the hydration water between phospholipid bilayers
Quasi-elastic neutron scattering study of the effects of metal cations on the hydration water between phospholipid bilayers
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DOI：
10.1063/1.5144012
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发表时间：
2020-03-30
影响因子：
4
通讯作者：
Yamada, T.
中科院分区：
文献类型：
--
作者：
Seto, H.;Yamada, T.
通过准弹性中子散射实验研究了结合在磷脂头基上的金属阳离子对水合水分子的影响。水合水可分为三种类型：紧密结合水、松散结合水和游离水，如在磷脂和不含盐的水的混合物的情况下观察到的。当CaCl2添加到混合物中时，这三种水分子的数量保持不变。相反，当向混合物中添加 MgCl2 或 FeCl2 时，紧密结合的水分子数量增加，而松散结合的水分子数量不受影响。这些结果与X射线衍射结果一致，表明离子结合在磷酸基团附近，增强了水合程度，而Ca2+离子结合在甘油基团附近，对水合水没有显着影响。结果表明，松散结合的水分子的数量由磷脂膜的性质决定。
The effects of metal cations bound at phospholipid headgroups on hydration water molecules were investigated by quasi-elastic neutron scattering experiments. The hydration water could be categorized into three types-tightly bound water, loosely bound water, and free water-as observed in the case of a mixture of phospholipid and water without salt. When CaCl2 was added to the mixture, the numbers of these three types of water molecules remained unchanged. In contrast, when MgCl2 or FeCl2 was added to the mixture, the number of tightly bound water molecules increased, while the number of loosely bound water molecules remained unaffected. These results are consistent with the x-ray diffraction results, which suggested that ions bind near the phosphate groups and enhance the extent of hydration, while Ca2+ ions bind near the glycerol groups with no significant effect on hydration water. The results demonstrate that the number of loosely bound water molecules is determined by the nature of the phospholipid membrane.