Goux W J, Smith H, Sparkman D R
Department of Chemistry, University of Texas at Dallas, Richardson 75083-0688, USA.
Neurosci Lett. 1995 Jun 16;192(3):149-52. doi: 10.1016/0304-3940(95)11628-a.
Amphiphiles are molecules which contain a polar head and a hydrophobic tail. When the head contains a chiral center, amphiphiles, incubated in the presence of some di- and trivalent metal ions, have been shown to form large fibrous molecular aggregates. In this study, naturally occurring brain cerebroside was tested to determine if it had sufficient amphiphilic properties to form similar supramolecular structures. When galactocerebroside was heated in the presence of magnesium, it was able to form tubules, vesicles and filaments. The filaments included long fibrils that aggregated into dense bundles and short fibrils that were associated to form smaller bundles. These fibrils were shown to be resistant to solubilization in boiling SDS in the presence of reducing agents. This is the first report of a naturally occurring glycolipid being able to form filaments. Since their structural and physical properties are similar to the paired helical filaments of Alzheimer's disease, they may serve as an experimental model for their assembly.
两亲分子是含有极性头部和疏水尾部的分子。当头部含有手性中心时，已表明两亲分子在一些二价和三价金属离子存在下孵育会形成大型纤维状分子聚集体。在本研究中，对天然存在的脑苷脂进行了测试，以确定它是否具有足够的两亲性质来形成类似的超分子结构。当半乳糖脑苷脂在镁存在下加热时，它能够形成小管、囊泡和细丝。细丝包括聚集成致密束的长纤维和相互关联形成较小束的短纤维。已表明这些纤维在还原剂存在下于沸腾的十二烷基硫酸钠中不溶解。这是关于天然存在的糖脂能够形成细丝的首次报道。由于它们的结构和物理性质与阿尔茨海默病的配对螺旋丝相似，它们可作为其组装的实验模型。
