Harland Christopher W, Botyanszki Zsofia, Rabuka David, Bertozzi Carolyn R, Parthasarathy Raghuveer
Department of Physics and Materials Science Institute, University of Oregon, Eugene, Oregon 97403, USA.
Langmuir. 2009 May 5;25(9):5193-8. doi: 10.1021/la804007a.
Lipid-derived desiccation resistance in membranes is a rare, unique ability previously observed only with trehalose dimycolate (TDM), an abundant mycobacterial glycolipid. Here we present the first synthetic trehalose glycolipids capable of providing desiccation protection to membranes of which they are constituents. The synthetic glycolipids consist of a simple trehalose disaccharide headgroup, similar to TDM, with hydrophobic tail groups of two 15- or 18-carbon chains. The synthetic trehalose glycolipids protected supported monolayers of phospholipids against dehydration even as minority components of the overall membrane, down to as little as 20 mol % trehalose glycolipid as assessed by assays of membrane fluidity. The dependence of the desiccation protection on the synthetic trehalose glycolipid fraction is nearly identical to that of TDM. The striking similarity of the desiccation resistance observed with TDM and the synthetic trehalose glycolipids, despite the variety of hydrophobic tail structures employed, suggests that interactions between the trehalose headgroup and surrounding molecules are the determining factor in dehydration protection.
膜中脂质衍生的抗干燥性是一种罕见的独特能力,此前仅在海藻糖二霉菌酸酯(TDM,一种丰富的分枝杆菌糖脂)中观察到。在此,我们展示了第一种能够为其作为成分的膜提供干燥保护的合成海藻糖糖脂。合成糖脂由一个简单的海藻糖二糖头部基团组成,类似于TDM,带有两条15或18个碳原子链的疏水尾部基团。合成海藻糖糖脂即使作为整个膜的少数成分,也能保护磷脂支撑单层免受脱水影响,通过膜流动性测定评估,低至20摩尔%的海藻糖糖脂。干燥保护对合成海藻糖糖脂比例的依赖性与TDM几乎相同。尽管使用了多种疏水尾部结构,但在TDM和合成海藻糖糖脂中观察到的抗干燥性惊人相似,这表明海藻糖头部基团与周围分子之间的相互作用是脱水保护的决定性因素。