对于空间分辨的交换测量,喷射电气的蛋白质离子的电子捕获解离
Jingxi Pan1, Jun Han, Christoph H Borchers
1Department of Chemistry, The University of Western Ontario, London, ON, N6A 5B7, Canada.
Journal of the American Chemical Society
|August 9, 2008
概括
电子捕获解离 (ECD) 成功地测量了交换 (HX) 后的蛋白质化模式. 这种质谱法最大限度地减少了杂乱,使得详细的蛋白质结构和动力学研究成为可能.
科学领域:
- 蛋白质组学是指蛋白质组学.
- 质谱测量质量谱测量
- 生物物理化学 生物物理化学
背景情况:
- 质谱 (MS) 对于在交换 (HX) 后分析蛋白质化有前途.
- 分子内迁移 (混杂) 可以扭曲气相碎片化中的同位素分布.
- 之前的研究表明,电子捕获解离 (ECD) 可以最大限度地减少短中的杂乱.
研究的目的:
- 评估ECD的可行性,用于分析大型蛋白质系统中的化模式.
- 用ECD-FT-MS来确定气相人工物,如杂乱在较大的蛋白质中是可以忽略不计的.
主要方法:
- 在蛋白质ubiquitin上进行溶液相胺交换 (HX).
- 通过里埃变换质谱法 (FT-MS) 使用电子捕获解离 (ECD) 分析化模式.
- 用核磁共振 (NMR) 数据比较ECD衍生的值水平.
主要成果:
- 在HX之后使用ECD成功分析了76-残留蛋白 ubiquitin.
- c和z离子的化水平与现有的NMR数据显示出很好的一致性.
- 观察到微不足道的杂乱和气相工件,验证了大型蛋白质的ECD方法.
结论:
- ECD-FT-MS是一种可行的方法,用于分析大型系统中的区域选择性蛋白质化模式.
- 该方法最大限度地减少了杂乱和气相工件,提供了准确的结构洞察力.
- 这为研究使用HX/ECD-FT-MS的蛋白质折叠,结构和动态开辟了道路.
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