质蛋白中的铜氧化还原循环严重取决于结合模式
Lin Liu1, Dianlu Jiang, Alex McDonald
1Department of Chemistry and Biochemistry, California State University, Los Angeles, Los Angeles, California 90032, USA.
Journal of the American Chemical Society
|June 29, 2011
概括
这种蛋白质叫做子蛋白.
科学领域:
- 生物化学 生物化学
- 神经科学是一个神经科学.
- 生物物理学的生物物理.
背景情况:
- 蛋白 (PrP) 在其N端域中结合铜.
- PrP吸收的铜与神经保护和细胞应激调节有关.
- 一个假设表明,高铜占用度会杀PrP的氧化还原循环,防止反应性氧物种的产生.
研究的目的:
- 直接测试 PrP 中高铜占用度灭氧化还原循环的假设.
- 为了研究铜结合模式在PrP的氧化还原活性中的作用.
- 阐明 PrP 与铜相互作用的机制及其对细胞功能的影响.
主要方法:
- 在低占用和高占用铜结合模式上进行了详细的pH取决于电化学测量.
- 独立的动力测量评估了酸盐的使用和过氧化物的产生.
- 在PrP的八重复 (OR) 和非OR区域中对铜结合的分析.
主要成果:
- 低铜占用完全灭了氧化还原循环.
- 高铜占用率导致通过催化氧降解来调节过氧化的产生.
- 从PrP的OR和非OR两部分观察到过氧化的产生.
结论:
- 目前的假设是高铜占用度灭PrP氧化还原循环被推翻了.
- 在高占用模式下,与PrP结合的铜的还氧循环受到调节,而不是灭.
- 过氧化的产生表明PrP在细胞信号通路中的作用.
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