芳香氨基酸的干扰与在核酸减少酶中的铁组合有关
Adam R Offenbacher1, Jun Chen, Bridgette A Barry
1Department of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
Journal of the American Chemical Society
|April 14, 2011
概括
这项研究使用紫外线共振拉曼光谱来揭示核酸减少酶 (RNR) 的结构变化. 它详细介绍了铁组装和铁基减少如何影响芳香氨基酸,并提供了对酶调节的见解.
科学领域:
- 生物化学 生物化学
- 频谱学是一种光谱学.
- 酶学 是一种酶学.
背景情况:
- 一级Ia核酸缩酶 (RNR) 是一种含有二铁和铁基的必需酶.
- 了解RNR的结构动态对于阐明酶功能和调节至关重要.
- 芳香氨基酸在酶的结构和活性中起着关键作用.
研究的目的:
- 为了研究由铁集群组件引起的RNRβ2子单元的结构变化.
- 描述与减少氨基基基 (Y122•) 相关的结构变化.
- 探索芳香氨基酸 (铁素,三酸,胺) 在RNR结构和功能中的作用.
主要方法:
- 使用了紫外共振拉曼 (UVRR) 差异光谱法.
- 在229nm时增强了UVRR光谱,探测了芳香氨基酸的贡献.
- 同位素标记和模型化合物比较用于光谱分配.
主要成果:
- 铁基的减少为Y122•和Y122产生了特定的拉曼波段,对其他芳香残留的干扰最小.
- 铁组件诱导了胺脱,得到了p(2) H定位研究的支持,显示了高的pK.
- 观察到氨酸和氨酸的乱;氨酸的变化表明的结合增加,金属中心附近的形状改变.
结论:
- 芳香氨基酸的静电和形状变化伴随着RNR中的金属集群组件.
- 乱的托残留物位于金属中心附近的受保护,低介电环境中.
- 这些形状变化可能有助于RNR中的金属结合的全调节.
相关概念视频
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01:31Translation
Lesson: Translation
Translation is the process of synthesizing proteins from the genetic information carried by messenger RNA (mRNA). Following transcription, it constitutes the final step in the expression of genes. This process is carried out by ribosomes, complexes of protein and specialized RNA molecules. Ribosomes, transfer RNA (tRNA), and other proteins produce a chain of amino acids—the polypeptide—as the end product of translation.
Translation Produces the Building Blocks of Life
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Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
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