金属离子促进了血红素与b型血红素蛋白的解离
Marcia R Mauk1, Federico I Rosell, A Grant Mauk
1Department of Biochemistry and Molecular Biology, Life Sciences Centre, 2350 Health Sciences Mall, University of British Columbia, Vancouver, BC V6T 1Z3 Canada.
Journal of the American Chemical Society
|October 31, 2009
概括
双碳酸盐缓冲剂促进金属离子与甲基球蛋白等蛋白质的相互作用,促进血红蛋白解离和阿波蛋白形成. 这种方法提供了一种新的方法来研究具有有限可溶性的蛋白质,而不需要恶劣的条件.
科学领域:
- 生物化学 生物化学
- 蛋白质化学 蛋白质化学
- 频谱学是一种光谱学.
背景情况:
- 血红蛋白在生物系统中至关重要.
- 研究具有有限溶解性的蛋白质可能具有挑战性.
- 传统的蛋白质分离方法通常涉及恶劣的条件.
研究的目的:
- 为了研究二碳酸盐缓冲体中的金属离子对血红蛋白结构的影响.
- 开发一种新方法来分离阿波蛋白.
- 在蛋白质研究中探索二碳酸盐缓冲器的实用性.
主要方法:
- 在二碳酸缓冲剂中对甲基球蛋白 (metMb) 和其他血红蛋白 (heme protein) 用Ni(2+),Cu(2+) 或Zn(2+) 的处理.
- 监测电子吸收光谱的变化.
- 用EDTA扭转光谱变化的情况.
- 阳离子交换染色学用于分离阿波-肌球蛋白.
- 与甲酶和胡卜过氧化酶的比较.
主要成果:
- 金属离子添加导致metMb的时间依赖的光谱变化,表明血红素解离.
- 同样的效应也被观察到对于细胞染色体b(5),胺二氧化酶和细胞染色体P450(cam).
- 在没有酸性或有机溶剂处理的情况下分离了Apo-myoglobin.
- catalase和胡卜过氧化酶显示了最小的光谱变化.
- 双碳酸盐促进了蛋白质溶解性和金属离子相互作用,破坏了血结合的稳定性.
结论:
- 二碳酸盐缓冲剂,与特定的金属离子结合,可以诱导从蛋白质中脱离.
- 这种方法提供了一种温和的方法来分离apoprotein.
- 二碳酸盐缓冲剂可能对研究具有有限溶解性的蛋白质有价值.
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