15菌的结构揭示了基因组组织和DNA包装/注射装置
Wen Jiang1, Juan Chang, Joanita Jakana
1National Center for Macromolecular Imaging, Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA.
Nature
|February 3, 2006
概括
研究人员使用冷电子显微镜揭示了沙门氏菌epsilon15的完整结构. 这揭示了DNA包装和注射所必不可少的非伊可沙赫德尔病毒成分,进步了我们对病毒机械的理解.
科学领域:
- 结构生物学是结构生物学.
- 病毒学 病毒学
- 微生物学 微生物学
背景情况:
- 许多二元体病毒具有缺乏二元体对称性的DNA包装和注射的关键组件.
- 这些不对称的组件很难用传统的二面体平均方法来解决.
研究的目的:
- 为了确定传染性沙门氏菌菌的完整结构epsilon15.
- 为了可视化和表征参与DNA传递的非二氧体状病毒组件.
主要方法:
- 单粒子冷电子显微镜 (cryo-EM) 没有icosahedral平均.
- 细菌的高分辨率图像重建epsilon15.
主要成果:
- 确定了沙门氏菌菌体epsilon15的完整结构,揭示了其二面体外和非二面体顶部部件.
- 顶点有一个12个子单元的门户综合体,内部核心,外部尾部枢纽和三元尾尖.
- 病毒DNA被包装在同轴线圈中,终端核酸准备通过门户综合体注入.
结论:
- 这项研究为复杂的病毒机器提供了前所未有的结构细节,具有混合的对称性.
- 这些发现表明,双链DNA病毒 (包括疹病毒) 的共同祖先是基于外蛋白折叠的双链DNA病毒.
- 非二元体平均化冷电磁场方法适用于其他复杂的生物纳米机器.
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