通过NMR实验和MD模拟的综合方法,可视化循环多域蛋白质的结构动态
Tomoki Sorada1, Erik Walinda2, Masahiro Shirakawa1
1Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Kyoto, Japan.
Protein science : a publication of the Protein Society
|August 26, 2023
概括
循环化稳定了Lys48结合的二维基因 (Ub2) 结构,增加了热稳定性和耐降解性. 这种循环形式表现出较慢的微秒域运动,与其线性对应物不同.
科学领域:
- 生物化学和结构生物学
- 蛋白质动力学和稳定性 蛋白质动力学和稳定性
背景情况:
- 已知蛋白质循环增强单域蛋白质的结构稳定性.
- 一种多域蛋白质Lys48结合的多比基因在人体细胞中经历循环,但其结构后果尚不清楚.
研究的目的:
- 调查循环化对循环lys48结合二维基因 (Ub2) 的结构稳定性和动态的影响.
- 阐明Ub2中循环化所赋予的结构稳定性背后的机制.
主要方法:
- 循环Ub2的热稳定性和蛋白质分解电阻的实验性表征.
- 核磁共振 (NMR) 放松分散实验以探测域间运动.
- 长粗粒度 (CG) 分子动力学 (MD) 模拟以可视化域动力学.
主要成果:
- 循环处理显著提高了Ub2的热稳定性和对蛋白质分解的抗性.
- 循环抑制了Ub2中的域间运动,但微秒形态交换仍然存在.
- CG-MD模拟显示,循环减缓了Ub2的内在纳秒域运动到微秒时间尺度.
结论:
- 循环化有效地稳定了与Lys48结合的diubiquitin的结构.
- 在循环Ub2中观察到的微秒动态是由减速的纳秒域运动解释的.
- 粗粒度的MD模拟为循环蛋白的结构稳定机制提供了宝贵的见解.
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