在SAM和ATP识别动机之间的结构相似性以及在SAM结合DNA甲基转移酶中的ATP结合的检测
Santhosh Sankar1, Preeti Preeti1, Kavya Ravikumar1
1Department of Biochemistry, Indian Institute of Science, Bangalore, 560012, Karnataka, India.
Current research in structural biology
|December 18, 2023
概括
S-adenosylmethionine (SAM) 结合蛋白具有共同的结构动机,这表明它们的演化趋同. 一个SAM结合点类型类似于ATP结合点,实验证据支持交叉连接体结合.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 分子进化分子进化
背景情况:
- S-adenosylmethionine (SAM) 是一个关键的辅助因子,参与各种生化反应,作为甲基群捐赠者等.
- SAM的多功能性源于它被许多具有不同序列和结构的蛋白质识别.
- 了解SAM结合的结构基础是解读其功能多样性的关键.
研究的目的:
- 在多种不同的蛋白质中调查SAM结合部位的结构模式.
- 确定SAM识别的共同原则和特征结构动机.
- 探索SAM和其他联结位点之间的潜在进化关系.
主要方法:
- 使用全对比较和聚类对SAM结合部位结构进行全面分析.
- 识别和描述不同的SAM地点类型及其共同原则.
- 在体外实验和局部定向突变发生,以验证结合部位的相似性和交叉连接体相互作用.
主要成果:
- 确定了四种不同的SAM结合部位类型,只有一个先前的特征很好.
- 对于每个站点类型来说,SAM识别的特征是共同的结构图案.
- 在一个SAM位点类型和已知的ATP结合位点之间发现了显著的相似性.
- 实验验证证证实,一种SAM结合蛋白可以结合和化ATP,并得到识别的共同结构动机的支持.
结论:
- 趋同的进化很可能塑造了SAM结合点,导致重复的结构动机.
- 识别的结构图案代表了SAM识别的优化残留安排.
- SAM和ATP结合点之间的重叠表明了交叉连接体结合的分子基础,并提供了融合进化的证据.
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