在大肠杆菌中对ABC输送器DppABCDF的结构性表征揭示了对二获取的洞察力
Panpan Li1,2, Manfeng Zhang1, Yihua Huang1,2
1National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.
PLoS biology
|March 7, 2025
概括
这项研究揭示了大肠杆菌中二载体DppABCDF的结构,显示了它的组装以及它如何导入. 激活需要DppA和ATP,而DppB的 scoop 图案有助于基质进口.
科学领域:
- 结构生物学是结构生物学.
- 微生物学 微生物学
- 生物化学 生物化学
背景情况:
- Prokaryotic ATP-binding cassette (ABC) 转运器对于将和抗生素通过细胞膜进口至关重要.
- 格兰阴性细菌中的二载体DppABCDF对于生理过程至关重要,具有难以捉摸的组装和导入机制.
研究的目的:
- 为了阐明DppABCDF输送组件和埃斯切里希亚大肠杆菌中的进口机制的结构基础.
- 使用冷电子显微镜 (cryo-EM) 确定DppBCDF转位器和全DppABCDF传送器的构造状态.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 确定了DppBCDF转位器 (apo和ATP模拟结合状态) 和全DppABCDF传送器的结构.
- 进行了ATPase活性测定,以调查载体的功能激活.
- 进行了细菌补充实验,以评估特定基因在基质进口中的作用.
主要成果:
- 大肠杆菌DppBCDF转位器是一种异质四体,与其他已知的转运体不同,含有 [4Fe-4S] 集群.
- 与ATP模拟结合的DppBCDF采用向内面向的形状,而全DppABCDF输送器采用向外面向的形状,ATP模拟稳定接口.
- DppBCDF转位器需要DppA和ATP来激活,而DppB中的周等离子模因与高效的二进口有关.
结论:
- 该研究提供了DppABCDF传送器的高分辨率结构,揭示了其独特的异构四元体组件和运输过程中的构造变化.
- 载体激活取决于与DPPA和ATP结合的相互作用,突出显示了进口的协调机制.
- 这些发现提供了关于 prokaryotic ABC 载体的分子机制和特定结构特征在基质吸收中的作用的见解.
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