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Analytical Techniques for Assaying Nitric Oxide Bioactivity
Published on: June 18, 2012
物理证据表明,基质结合可以防止在化应激下循环氧基因酶失活
Ruba S Deeb1, Cynthia Cheung, Tal Nuriel
1Department of Pathology, Weill Cornell Medical College of Cornell University, 1300 York Avenue, New York, New York 10065, USA. rsdeeb@med.cornell.edu
Journal of the American Chemical Society
|March 4, 2010
概括
基质结合保护循环氧化酶-1 (COX-1) 免受反应性物种的失活. 这一发现揭示了氧化应激期间COX-1活动的新型保护机制.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 分子生物学分子生物学
背景情况:
- 循环氧化原酶 (COX) 酶通过不同的活性位点催化前列腺素生物合成.
- 对COX酶的调节和功能还没有完全了解.
- 氧化应激会产生反应性物种,这些物种会改变COX酶,改变前列腺素的产生.
研究的目的:
- 为了研究环氧化原酶-1 (COX-1) 对酸性失活的保护机制.
- 为了确定基质占用在反应性物种对COX-1调节中的作用.
主要方法:
- 位点定向的突变发生,以确定关键的氨酸残留物.
- 酶动力学测试测量COX-1活动.
- 质谱测量以确认蛋白质的修饰.
主要成果:
- 在Tyr385上,COX-1经过选择性化,导致催化不活化.
- 基质与COX-1活性部位的结合可以防止Tyr385化.
- 当活性位点被基质占据时,酸盐被重定向到其他氨酸残留物,从而保持酶活性.
结论:
- 基质占用是保护COX-1免受酸性失活的关键因素.
- 这项研究揭示了在涉及氧化应激的病理生理条件下对COX-1调节和保护的新机制.
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