血/O2/*NO氧化二氧化原酶 (NOD) 反应活性:通过假定的血-氧化中间体进行化
Mark P Schopfer1, Biplab Mondal, Dong-Heon Lee
1Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, USA.
Journal of the American Chemical Society
|July 25, 2009
概括
血-超氧复合物与氧化 (NO) 反应形成酸铁 (III) 化合物,模仿氧化二氧化基酶. 这种血化学反应可能涉及过氧酸盐中间体,并导致基质化.
科学领域:
- 生物有机化学 生物有机化学
- 氧化化学 有氧化化学
- 氧化信号传输 氧化信号传输
背景情况:
- 氧化 (NO) 是一个关键的信号分子,参与各种生理过程.
- 氧化二氧化基酶 (NODs) 是一种能够排毒NO的血红蛋白.
- 了解复合物与NO的反应性对于阐明生物NO代谢至关重要.
研究的目的:
- 为了研究-超复合物与氧化的反应.
- 探索过氧酸盐中间体在这种反应中的潜在参与.
- 在模型系统中模拟氧化二氧化基酶的酶活性.
主要方法:
- 合成和表征一个由ortho-difluoro替代的tetraarylporphyrinate heme-superoxo复合物.
- 血-超复合体与氧化的反应.
- 进行X射线晶体学以确定反应产物的结构.
- 在外源基质如2,4-di-tert-butylphenol的存在下对反应的研究.
主要成果:
- 血-超氧复合物与氧化发生反应,产生酸铁 (III) 化合物.
- 一种过氧酸盐中间体参与了反应途径.
- 在2,4-di-tert-butylphenol的存在下,发生了的o-化,产生2,4-di-tert-butyl-6-nitrophenol.
- 最终的铁制品被确定为一种氧铁 (III) 种.
结论:
- 血/O2/NO化学反应可能导致酸铁III物种的形成,模仿NOD活动.
- 氧酸盐中间体可能参与其中,可能会对外源基质造成氧化和酸性损伤.
- 这种模型系统提供了对血红蛋白与氧化的复杂反应性的洞察.
相关概念视频
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