再组合α-synuclein的Cu2+结合方式 - - 来自EPR光谱学的见解
Simon C Drew1, Su Ling Leong, Chi L L Pham
1Department of Pathology, The University of Melbourne, Victoria 3010, Australia.
Journal of the American Chemical Society
|May 23, 2008
概括
与Cu2+的α-synuclein (alphaS) 相互作用与帕金森病有关. 这项研究使用了EPR光谱学来描述四种不同的Cu2+) 结合模式在全长的alphaS中,跨越生理pH范围.
科学领域:
- 生物化学 生物化学
- 神经科学是一个神经科学.
- 频谱学是一种光谱学.
背景情况:
- 与Cu(2+) 的α-synuclein (alphaS) 相互作用与帕金森病 (PD) 有关.
- 在全长的alphaS中,Cu(2+) 结合模式的理解比截断的模型要少.
- 了解这些相互作用对于PD病变研究至关重要.
研究的目的:
- 描述复合人类alphaS.的Cu(2+) 结合方式.
- 为了研究Cu ((2+) 协调的pH依赖性变化.
- 为了提供对alphaS-Cu(2+) 相互作用的全面了解.
主要方法:
- 电子偏磁共振 (EPR) 光谱学.电子偏磁共振 (EPR) 光谱学.
- 电子自旋回声封膜调制 (ESEEM) 研究.
- 位点定向突变发生 (H50N) 探测特定的结合位点.
主要成果:
- 在生理pH下,在野生类型的alphaS中确定了两个N端Cu(2+) 结合模式.
- 突变H50N分离了一个模式,与{NH2,N(-),β-COO(-),H2O}协调相关.
- 在pH 5.0下,His50的结合减少,揭示了新的模式,包括在Asp121.1.下C端结合.
- 在pH值5.0-7.4.4之间,共发现了四种不同的Cu(2+) 结合模式.
结论:
- 重组alphaS表现出多种pH依赖的Cu2+) 结合方式.
- 这些发现提供了有关PD的alphaS-Cu(2+) 相互作用的更完整的图像.
- 描述的结合模式为进一步研究在疾病中的alphaS金属结合提供了基础.
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