腺-5'-酸酸盐激酶与可光激活的原子氧前体进行氧转换
Miao Zhang1, Geoffrey E Ravilious, Leslie M Hicks
1Department of Chemistry, Saint Louis University, 3501 Laclede Avenue, Saint Louis, Missouri 63103, USA.
Journal of the American Chemical Society
|October 3, 2012
概括
研究人员研究了一种特定的化学反应如何影响腺素-5'-硫酸盐激酶 (APSK). 他们发现,光诱导的氧化特别通过形成二硫化键来抑制APSK,从而将其活性单体形式改变为受抑制的二维状态.
科学领域:
- 生物化学 生物化学
- 植物生理学 植物生理学
- 摄影化学的使用.
背景情况:
- 腺-5'-硫酸盐激酶 (APSK) 对于植物中的硫酸盐同化至关重要.
- APSK的活性是由Cys86和Cys119之间的一种子单位间的二硫化键调节的.
- 氧化应激会影响酶的功能和调节.
研究的目的:
- 为了研究从2,8-dihydroxymethyldibenzothiophene S-oxide中产生的植物APSK由O((3) P) 的特定氧化.
- 为了确定这种氧化是否针对APSK的调节性二硫化物键位.
主要方法:
- 在 2,8-二氧化甲基二二二氧化 S-氧化物的存在下对 APSK 的辐射.
- 对APSK活动和辐射后四级结构变化的分析.
- 用光谱和生物化学分析来确认二硫化物键的形成.
主要成果:
- 通过使用2,8-dihydroxymethyldibenzothiophene S-oxide.实现了APSK的光诱导氧化.
- 观察到活跃单体APSK的近量化转化为受抑制的二度APSK.
- 证据强烈表明,Cys86-Cys119二硫化键的形成介导了这种抑制.
结论:
- O(((3) P) 能够在其调节性二硫化键上特别氧化和抑制植物APSK.
- 这种光诱导的氧化提供了一种研究APSK调节和功能的方法.
- 了解这种机制可以了解植物的硫代谢和氧化条件下的酶调节.
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