分析FctB3晶体结构,并深入了解其结构稳定和柱状链接机制
Katsuki Takebe1,2,3, Mamoru Suzuki2, Takeshi Sangawa2
1Department of Oral and Maxillofacial Oncology and Surgery, Osaka University Graduate School of Dentistry, 1-8, Yamadaoka, Suita, Osaka, Japan.
Archives of microbiology
|November 23, 2023
概括
来自Streptococcus pyogenes的FctB3柱状结构揭示了与FctB9相比,其欧米茄环和富含proline的尾巴的差异. 这些结构变化促进了柱子相互作用和柱子组装.
科学领域:
- 微生物学 微生物学
- 结构生物学 结构生物学
- 生物化学 生物化学
背景情况:
- 杆菌pyogenes利用 pili 进行粘附和毒性.
- FCT 3 型基因组区域编码由多个基因组成的 pili,包括 FctB.
- 了解柱子结构对于破译柱子组装和功能至关重要.
研究的目的:
- 从血清型M3Streptococcus pyogenes菌株中确定FctB基柱 (FctB3) 的3D结构.
- 将FctB3结构与从血清型T9菌株中先前确定的FctB9结构进行比较.
- 阐明柱子相互作用和柱子组装的结构基础.
主要方法:
- 使用X射线晶体学以2.8 Å分辨率确定FctB3结构.
- 进行了FctB3和FctB9之间的结构比较.
- 研究了FctB,FctA和Cpa之间的相互作用,包括SipA陪伴者的作用.
主要成果:
- FctB3的结构包括一种类似免疫球蛋白的域和一种富含proline的尾巴.
- 在FctB3和FctB9.9之间观察到欧米茄 (Ω) 循环结构和富含proline的尾部方向的关键差异.
- FctB3是通过疏水性相互作用稳定,与FctB9不同,FctB9利用异酸键.
- FctA似乎更适合与FctA进行链接,而不是FctB3.
- 涉及FctB,Cpa和FctA的异构体形成是由SipA陪伴者介导的.
结论:
- 确定的FctB3结构为这个关键支柱提供了一个替代的结构模型.
- 在 Ω 循环和富含proline 尾部的结构变化影响着柱子相互作用和柱子组装.
- 这些发现提供了对Streptococcus pyogenes中控制柱状形成的分子机制的见解.
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