Ebp pilus 轴形成和固定在抗万科胺素抗性肠球菌中的结构基础
Vinay Sharma1, Vengadesan Krishnan1
1Laboratory of Structural Microbiology, Regional Centre for Biotechnology, NCR Biotech Science Cluster, Faridabad, India.
The FEBS journal
|July 3, 2025
概括
Enterococcus faecalis使用内心炎和生物膜相关 pili (Ebp) 感染. 我们确定了 EbpC 和 EbpB 柱子的晶体结构,揭示了它们的域组织和在柱子组装中的潜在作用.
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:
- 菌 (Enterococcus faecalis) 是一种机会性病原体,会引起诸如内心炎和尿路感染之类的重大感染.
- 内心炎和与生物膜相关的 pili (Ebp) 对 E. faecalis 的粘附,殖民,生物膜形成和毒性至关重要.
- Ebp柱由EbpA,EbpB和EbpC子单元组成,EbpC构成脊柱,EbpA/EbpB位于尖端/底部.
研究的目的:
- 确定来自E. faecalis和E. faecium的EbpC和EbpB柱的实验晶体结构.
- 阐明EBP柱子的结构特征及其在柱子组装和功能中的潜在作用.
- 为了解肠球菌堆形成和制定有针对性的干预措施提供结构基础.
主要方法:
- 使用X射线晶体学来确定EBpC和EBpB柱体及其同类的结构.
- 结构分析的重点是域的排列,折叠 (CnaB-CnaA-CnaB),异类键和皮林图案.
- 运用计算机建模来提出EBP柱子组件的结构模型.
主要成果:
- EbpC和EbpB的晶体结构分别显示了四个和三个线性排列的免疫球蛋白类域.
- EbpB表现出脊柱柱的特征,具有典型的柱柱图案和CnaB-CnaA-CnaB折叠,包括一个完整的异结.
- EbpC具有具有CnaB-CnaA-CnaB折叠和内域异类键的刚性C终端片段,而其N终端域缺乏异类键,导致"串上的珠子"结构.
结论:
- 确定的结构为EBP柱的分子结构提供了详细的见解.
- 结构分析确定了关键的残留物,这些残留物参与了通过分子间共价链接通过排序酶介导的柱子组装.
- 这些发现有助于制定基于结构的策略,以向肠球菌和打击感染.
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