全长背景破坏了蛋白A的IgG结合域的折叠
Kosar Rahimi1, Albert Halbing1, Minh Ngoc Nguyen1
1Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas, 77204, USA.
bioRxiv : the preprint server for biology
|December 19, 2025
概括
多域蛋白,如葡萄球菌蛋白A (SpA) 可能不会折叠成独立的模块. 全长SpA存在于一个混乱的集合体中,挑战AI预测和模块化蛋白质设计假设.
科学领域:
- 结构生物学 结构生物学
- 蛋白质折叠 蛋白质的折叠
- 生物物理学的生物物理.
背景情况:
- 多域蛋白质通常被认为是独立的,稳定的域.
- 这种模块化是结构生物学和蛋白质设计的基石.
- 葡萄球菌蛋白A (SpA) 是一种多域蛋白质,具有五个免疫球蛋白 (Ig) 结合域.
研究的目的:
- 为了研究全长的葡萄球菌蛋白A (SpA) 的折叠行为.
- 挑战在多域蛋白中独立域稳定性的普遍观点.
- 在热力学背景下评估基于AI的结构预测模型的局限性.
主要方法:
- 研究了全长SpA及其个体Ig结合域的折叠行为.
- 利用生物物理技术分析蛋白质结构和溶液中的稳定性.
- 将实验结果与人工智能模型的预测进行比较.
主要成果:
- 全长SpA及其在全长构造中的个别域在解决方案中没有采用稳定的3D结构.
- SpA是一个紧的,主要是无序的集体,其余的二次结构.
- 单个Ig结合域的折叠状态在全长蛋白内是热力学上不利的.
- 人工智能模型预测了折叠结构,但这些并没有在实验中观察到.
结论:
- 多域蛋白质的折叠可能不是严格的模块化,挑战现有的假设.
- 热力学背景对于理解蛋白质折叠和稳定性至关重要.
- 当前的人工智能预测器在不考虑热力学景观时存在局限性.
- 发现影响蛋白质结构验证,多域蛋白质理解和生物技术设计.
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