在离子氧化过程中的假体血修饰. 通过胡卜氧化酶证明化物氧化
Liusheng Huang1, Grzegorz Wojciechowski, Paul R Ortiz de Montellano
1Department of Pharmaceutical Chemistry, University of California, 600 16th Street, San Francisco, California 94143-2280, USA.
Journal of the American Chemical Society
|April 14, 2005
概括
胡卜过氧化酶 (HRP) 现在可以氧化化物和化物,形成修饰的血群. 这一发现表明,过氧化酶需要最小的变化才能获得独特的化物氧化能力.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
背景情况:
- 骨髓氧化酶 (MPO),乙氨基氧化酶 (EPO) 和氧化酶氧化化物,不同于大多数过氧化酶,如卜氧化酶 (HRP).
- HRP通常只氧化化物,有时还会氧化化物.
研究的目的:
- 为了研究化物 (Br-) 和化物 (Cl-) 由HRP的氧化.
- 探索化物氧化 HRP 的机制及其对血红素修饰的影响.
主要方法:
- 在酸性pH下用Br-或Cl-和过氧化 (H2O2) 化HRP.
- 质谱法用于分析血红组修饰.
- 与无蛋白质的血反应和在中性pH的反应进行比较.
主要成果:
- 在酸性pH值下,HRP催化化,并用化物修改其血基,形成水素添加物.
- 当HRP与Cl-和H2O2.2反应时,会发生类似的血红蛋白修饰,包括一个中添加物.
- 这些修改取决于pH值和HRP蛋白的存在.
结论:
- HRP首次展示了氧化Cl-的能力.
- 在化物氧化过程中由HRP进行的假体血修饰表明,MPO/EPO类活性需要最小的蛋白质调.
- 这项研究提出了关于MPO和EPO体如何在化物氧化过程中避免自我修饰的问题.
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