在I类核糖核酸还原酶和相关的双核非血红素铁酶中的氧类中间体
Kasper P Jensen1, Caleb B Bell, Michael D Clay
1DTU-Chemistry, Technical University of Denmark, Building 207, DK 2800 Kgs. Lyngby, Denmark.
Journal of the American Chemical Society
|August 12, 2009
概括
计算化学揭示了水或质子如何激活非血红二铁核糖核酸减少酶中的氧中间体. 这项研究确定了二氧化激活的关键反应途径,这对于酶功能至关重要.
科学领域:
- 生物化学 生物化学
- 计算化学计算化学
- 酶学 是一种酶学.
背景情况:
- 非血红蛋白二铁酶,如核糖核酸减少酶,对于生物过程至关重要.
- 了解这些酶中二氧化碳激活的机制对于它们的功能至关重要.
研究的目的:
- 系统地研究非血二铁核糖核酸减少酶中可能存在的化学氧类中间体.
- 阐明水或质子在激活这些中间体中对于酶反应的作用.
主要方法:
- 使用密度函数计算与光谱校准.
- 计算了平衡结构,振动频率,莫斯尔同位素转移和电子性质.
- 研究了O{2},质子和水的结合能.
主要成果:
- 描述了各种氧中间体及其性能.
- 确定了两种潜在的中间激活反应途径,涉及水或质子结合.
- 表明水协调可以诱导在晶体结构中观察到的形状变化.
结论:
- 质子或水与二铁位点的结合促进了电子结构的变化,激活了过氧中间体.
- 为了激活过氧中间体,提出了两种途径,导致Fe (III) Fe (IV) 中间体X的形成.
- 这些发现为这种酶类O(2) 反应期间的碳酸盐构造变化提供了新的理由.
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