粉样蛋白上层结构的奇拉性
Noa Rubin1, Emanuel Perugia, Michal Goldschmidt
1Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel 76100.
Journal of the American Chemical Society
|March 15, 2008
概括
粉样纤维呈现出明显的螺旋结构. 研究人员发现,虽然大多数粉样蛋白形成左撇子螺旋体,但血清粉样蛋白A会形成右撇子螺旋体,揭示结构组织影响性.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 生物物理学的生物物理.
背景情况:
- 粉样蛋白是与20多种疾病相关的蛋白质聚合物.
- 粉样纤维具有特有的交叉β结构,形成螺旋式上层结构.
研究的目的:
- 用高分辨率显微镜研究粉样蛋白超结构的性.
- 确定分子性是否决定了粉样蛋白中超分子螺旋组织.
主要方法:
- 高分辨率扫描电子显微镜 (SEM).
- 低温扫描电子显微镜 (Cryo-SEM). 低温扫描电子显微镜
主要成果:
- 阿贝塔1-40的粉样蛋白和溶酶的粉样蛋白仅仅形成左手螺旋.
- 血清粉样蛋白A (SAA1-12) 基形成完全右侧螺旋.
- 类反体 ((R) - 氨基酸) 聚合成左手螺旋体.
结论:
- SAA1-12粉样蛋白的右撇子是固有的特征.
- 左侧螺旋与传统的β-sheet模型对齐.
- 右手SAA1-12螺旋表明其交叉β结构可能不涉及β片,突出结构组织在超分子性中的作用.
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