Kent Ben, Hunt Taavi, Darwish Tamim A, Hauß Thomas, Garvey Christopher J, Bryant Gary
Helmholtz-Zentrum Berlin, Institute Soft Matter and Functional Materials, , Hahn-Meitner-Platz 1, D-14109 Berlin, Germany.
J R Soc Interface. 2014 Mar 19;11(95):20140069. doi: 10.1098/rsif.2014.0069. Print 2014 Jun 6.
Trehalose, a natural disaccharide with bioprotective properties, is widely recognized for its ability to preserve biological membranes during freezing and dehydration events. Despite debate over the molecular mechanisms by which this is achieved, and that different mechanisms imply quite different distributions of trehalose molecules with respect to the bilayer, there are no direct experimental data describing the location of trehalose within lipid bilayer membrane systems during dehydration. Here, we use neutron membrane diffraction to conclusively show that the trehalose distribution in a dioleoylphosphatidylcholine (DOPC) system follows a Gaussian profile centred in the water layer between bilayers. The absence of any preference for localizing near the lipid headgroups of the bilayers indicates that the bioprotective effects of trehalose at physiologically relevant concentrations are the result of non-specific mechanisms that do not rely on direct interactions with the lipid headgroups.
海藻糖是一种具有生物保护特性的天然二糖，因其在冷冻和脱水过程中保护生物膜的能力而被广泛认可。尽管对于实现这一过程的分子机制存在争议，且不同机制意味着海藻糖分子相对于双层膜有截然不同的分布，但尚无直接实验数据描述脱水过程中海藻糖在脂质双层膜系统中的位置。在此，我们利用中子膜衍射确凿地表明，在二油酰磷脂酰胆碱（DOPC）系统中，海藻糖的分布呈高斯分布，中心位于双层膜之间的水层。对双层膜脂质头部附近定位没有任何偏好，这表明在生理相关浓度下，海藻糖的生物保护作用是不依赖于与脂质头部直接相互作用的非特异性机制的结果。
