通过固态核磁共振光谱检测的Y145Stop人类蛋白粉样纤维的形状灵活性
Jonathan J Helmus1, Krystyna Surewicz, Witold K Surewicz
1Department of Chemistry, The Ohio State University, Columbus, Ohio 43210, USA.
Journal of the American Chemical Society
|February 4, 2010
概括
人类蛋白 (huPrP23-144) amyloid 的 N-终端域是灵活的,并且类似于随机卷轴. 核心残留物表现出限制运动,但粉样核中的一些缓慢动态表明潜在的化学交换现象.
科学领域:
- 生物物理学的生物物理.
- 结构生物学 结构生物学
- 神经科学是一个神经科学.
背景情况:
- 一种C截断的人类蛋白 (huPrP23-144) 突变的粉样聚合物与遗传性粉样血管病变有关.
- 这些聚合物在C端附近具有刚性,富含β片的粉样核.
- huPrP23-144的N端残留物表现出显著的形状灵活性.
研究的目的:
- 直接观察和描述huPrP23-144粉样蛋白的柔性N端域.
- 为了研究huPrP23-144.的粉样核中的潜在分子运动.
- 用固态NMR (SSNMR) 量化测量核心残留物的动态.
主要方法:
- 采用了基于2D J合的魔法角旋转 (MAS) 的SSNMR技术.
- 基于交叉偏振 (CP) 的3DSSNMR光谱进行了信号强度分析.
- 脊柱双极顺序参数和横旋放松率对核心残留物进行了定量测量.
主要成果:
- 对huPrP23-144粉样蛋白的N端域进行了直接观察,显示了随机卷状形状.
- 核心残留物在亚微秒时间尺度上表现出有限,均的运动,类似于微晶蛋白.
- 核心内横向放松速率的变化表明化学交换现象缓慢,微秒到毫秒的时间尺度.
结论:
- 粉样蛋白 huPrP23-144 的 N-终端域是高度灵活的.
- 虽然粉样核在很大程度上是刚性的,但证据表明这个区域内的分子运动缓慢,以及潜在的化学交换.
- 这些发现提供了关于蛋白粉样蛋白结构的动态性质的见解.
相关概念视频
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Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
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Overview


