通过水氧铁基细胞染色体P450来氧化烯
Shengxi Jin1, Thomas M Makris, Thomas A Bryson
1Department of Chemistry and Biochemistry and the School of Medicine, University of South Carolina, Columbia, South Carolina 29208, USA.
Journal of the American Chemical Society
|March 20, 2003
概括
细胞染色体P450cam的T252A突变不能形成活性氧中间体,但仍然可以环氧化烯酸. 这通过一种水氧-铁中间体发生,作为一种独特的电友性氧化剂.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 化学动力学 化学动力学
背景情况:
- 细胞染色体P450酶对于氧化代谢至关重要.
- 众所周知,P450cam的T252A突变体在形成高价值的oxoferryl中间体方面存在缺陷.
- 这种缺陷阻止了其正常基质 - - 坎佛被化.
研究的目的:
- 为了研究T252A P450cam突变体与olefins的催化活性.
- 为了确定T252A P450cam在缺少氧中间体的情况下氧化烯的机制.
- 为了探索烯酸氧化氧化过程中水氧铁中间体的作用.
主要方法:
- 用olefin基质进行酶动力学测试.
- 用光谱分析来表征反应中间体.
- 放射性分析研究以确认中间形成.
- 二氧化减氧试验.氧化减氧试验.
主要成果:
- T252A P450cam成功地环氧化了olefins,尽管缺少了oxoferryl中间体.
- 突变者保留了形成氧铁反应周期中间体的能力.
- 观察到二氧化物减少为过氧化,支持水-铁中间体的形成.
结论:
- P450cam的氧铁中间体可以作为olefin环氧化的一种电友性氧化剂.
- 这一发现揭示了P450酶的替代催化途径.
- 它扩大了我们对P450反应机制和基质范围的理解.
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