激素传输由在核酸还原酶子单元界面上的质子传输网络促进
Chang Cui1, David Y Song1, Catherine L Drennan2,3,4
1Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States.
Journal of the American Chemical Society
|February 22, 2023
概括
核酸减少酶 (RNR) 对于DNA合成至关重要. 这项研究揭示了一个质子穿网络,涉及RNR酶活性和脱氧核化物形成的特定残留物.
科学领域:
- 生物化学
- 酵素学
- 分子生物学
背景情况:
- 核酸减少酶 (RNR) 是催化脱氧核酸合成的重要酶.
- 来自大肠杆菌的Ia类RNR涉及形成活性α'ββ'复合体的α和β子单元.
- 长距离的质子合电子传输途径对于RNR活动至关重要.
研究的目的:
- 阐明Y356[β]残留物和相关极点网络在RNR功能中的作用.
- 研究大肠杆菌Ia类RNR的α/β接口上的质子转移机制.
主要方法:
- 使用正规和非自然氨基酸进行位点定向的突变发生.
- 通过光化学生成Y356基.
- 暂时吸收光谱和脱氧核酸形成试验.
主要成果:
- Y356[β]残留物和Y731[α]跨越了α/β接口.
- 一个残留物网络 (E52[β],R331[α],E326[α],E326[α']) 对于Y356的氧化至关重要.
- 这种网络在Y356氧化过程中促进了从接口到散装溶剂的质子穿.
结论:
- 已识别的极性网络 (E52[β],R331[α],E326[α],E326[α']) 对RNR活动至关重要.
- 这种网络在质子转移中起着关键作用,支持RNR的催化循环.
- 了解这种机制可以了解脱氧核酸生物合成的调节.
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