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细胞外收缩注射系统的冷电磁结构和组装
Feng Jiang1, Ningning Li2, Xia Wang1
1NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PRC.
Cell
|March 26, 2019
概括
收缩注入系统 (CIS) 是穿孔细胞的纳米设备. 研究人员确定了Photorhabdus毒性带 (PVC) 的结构, 揭示了其作为生物传递工具的机制和潜力.
科学领域:
- 结构生物学
- 微生物学
- 纳米技术
背景情况:
- 收缩注入系统 (CIS) 是细胞穿孔纳米机器.
- CIS与收缩式尾巴菌具有共同的进化起源.
- Photorhabdus毒性盒 (PVC) 是一种在细菌和古生物中发现的细胞外CIS.
研究的目的:
- 通过冷电子显微镜 (cryo-EM) 来确定P. asymbiotica完整的PVC结构.
- 阐明PVC的结构特征和潜在的功能机制.
- 提供关于CIS及其应用的更广泛的见解.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 来确定PVC的结构.
- 多兆装置的结构分析.
主要成果:
- 超过10MDa的PVC结构类似于简化的T4菌体尾巴.
- 它具有六角基板,六个纤维和一个封闭的117nm管干.
- 管和膜蛋白的三种变体表明功能专业化,终端盖锁定了膜在收缩前的状态.
结论:
- 确定PVC结构为了解CIS机制提供了一个框架.
- 这些发现突显了PVC作为生物和治疗应用的交付工具的潜力.
- 这项研究提升了我们对纳米生物机械及其工程潜力的了解.
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