Choo-Smith L P, Surewicz W K
Department of Pathology, Case Western Reserve University, Cleveland, OH 44106, USA.
FEBS Lett. 1997 Feb 3;402(2-3):95-8. doi: 10.1016/s0014-5793(96)01504-9.
The interaction between Alzheimer amyloid peptide A beta(1-40) and membrane lipids was studied by circular dichroism spectroscopy under the conditions of physiologically relevant ionic strength and neutral pH. The peptide binds to the membranes containing ganglioside GM1 and upon binding undergoes a conformational transition from random coil to an ordered structure rich in beta-sheet. This interaction appears to be ganglioside-specific as no changes in A beta(1-40) conformation were found in the presence of various phospholipids or sphingomyelin. The isolated oligosaccharide moiety of the ganglioside was ineffective in inducing alterations in the secondary structure of A beta(1-40). No interaction was observed between ganglioside GM1 and the N-terminal peptide fragment A beta(1-28). Binding to the ganglioside is likely to modulate the neurotoxic and/or amyloidogenic properties of A beta(1-40).
在生理相关离子强度和中性pH条件下，通过圆二色光谱研究了阿尔茨海默病淀粉样肽Aβ(1-40)与膜脂之间的相互作用。该肽与含有神经节苷脂GM1的膜结合，结合后会发生从无规卷曲到富含β-折叠的有序结构的构象转变。这种相互作用似乎具有神经节苷脂特异性，因为在存在各种磷脂或鞘磷脂的情况下，未发现Aβ(1-40)构象发生变化。神经节苷脂的分离寡糖部分在诱导Aβ(1-40)二级结构改变方面无效。未观察到神经节苷脂GM1与N端肽片段Aβ(1-28)之间的相互作用。与神经节苷脂的结合可能会调节Aβ(1-40)的神经毒性和/或淀粉样蛋白生成特性。
