UvrC 是一个O2-敏感的 [4Fe4S] 辅因子
Rebekah M B Silva1, Michael A Grodick1, Jacqueline K Barton1
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States.
Journal of the American Chemical Society
|May 30, 2020
概括
研究人员研究了UvrC中的4Fe4S集群,这是一种DNA修复酶. 他们发现这个铁硫团对UvrC至关重要.
科学领域:
- 生物化学
- 分子生物学
- 生物有机化学
背景情况:
- [4Fe4S]集群是所有生命领域的酶中的重要辅因子.
- 在核酸加工酶中观察这些集群是很困难的,因为它们的特征和辅因子可变性很弱.
- 对细菌核酸切除修复 (NER) 内核酶UvrC进行了研究,以确定其是否涉及4Fe4S集群.
研究的目的:
- 调查UvrC酶中的4Fe4S集群的存在和作用.
- 描述辅因子的稳定性及其对UvrC的DNA结合亲和力和功能的影响.
- 在UvrC中确定 [4Fe4S] 集群的氧化还原活性.
主要方法:
- 序列对齐和无氧净化技术.
- 铁量化,紫外线可见和电子磁共振 (EPR) 光谱.
- DNA结合测试和DNA电化学
主要成果:
- UvrC表现出与 [4Fe4S] 集群协调相一致的特征 (60-70%的内置).
- 在UvrC中的4Fe4S集群易受氧化降解.
- 与apo-UvrC相比,Holo-UvrC显示了高亲和度的DNA结合 (80-100nM).
- [4Fe4S]集群具有氧化还原活性,并参与DNA介导的电荷传输 (中点电位为90mV与NHE).
结论:
- [4Fe4S]集群对UvrC功能至关重要,增强其DNA结合亲和力.
- 辅助因子的氧化还原活性表明它在简单的结合之外的DNA修复机制中发挥了作用.
- 了解UvrC中的4Fe4S集群,可以了解DNA修复途径和金属酶功能.
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