不同样本制备技术对扫描电子和扫描传输电子显微镜成像病毒和类似病毒的粒子的影响
Monika Kąkol1, Ezher Tagliasacchi2, Andrzej Borkowski3
1Faculty of Geology, University of Warsaw, Warsaw, Poland.
Frontiers in microbiology
|November 30, 2023
概括
选择正确的样本准备和成像技术对于可视化病毒和病毒样粒子 (VLP) 至关重要. 不同的协议会影响菌体和生物膜病毒的质量和保存.
科学领域:
- 微生物学 微生物学
- 电子显微镜电子显微镜
- 结构生物学 结构生物学
背景情况:
- 扫描电子显微镜 (SEM) 和扫描传输电子显微镜 (STEM) 对于可视化病毒和类似病毒的粒子 (VLP) 来说至关重要.
- 选择了P1和F6的细菌体,以及来自岩生物膜的病毒进行结构分析.
- 这些微观实体的有效可视化在很大程度上依赖于优化的准备和成像协议.
研究的目的:
- 评估和比较三个不同的样本准备协议用于SEM和STEM病毒和VLP的成像.
- 确定保护不同类型病毒的结构完整性的最佳方案,包括菌体和生物膜相关病毒.
- 评估化学处理和成像参数对图像质量和数据解释性的影响.
主要方法:
- 开发并测试了三种方案:"完整"",简化"和"一次性"的样品准备.
- 利用SEM和STEM进行来自自然生物膜的菌体 (P1, Φ6) 和病毒的高分辨率成像.
- 分析了化学固定 (OsO4,乙酸) 和涂层对样品保存和图像清晰度的影响.
主要成果:
- "完整"协议成功可视化了P1菌体,而"简化"协议对F6有效,但对P1无效,表明灵敏度差异.
- 生物膜中的病毒由于矿化和聚合而存在挑战,复杂化了表征.
- "一次性"协议保留了菌体尾巴,但引入了过度的试剂涂层,降低了整体图像质量和清晰度.
结论:
- 样本准备协议显著影响通过SEM/STEM观察到的病毒和VLP的分辨率和保存.
- 图像技术和制备方法的选择必须根据特定的病毒类型和研究目标量身定制.
- 精心优化对于获得高质量,信息图像对于准确的病毒表征至关重要.
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