五角体的开花,一种由不同的微型病毒使用的基因组传递的保存机制
Pavol Bardy1,2, Conor I W MacDonald1, Paul C Kirchberger3
1York Structural Biology Laboratory, Department of Chemistry, University of York, Heslington, United Kingdom.
mBio
|March 19, 2025
概括
我们发现了像Ebor这样的大型微病毒如何使用独特的状结构来感染细菌. 它们的"penton blooming"机制允许通过表面突出通过宿主细胞附着后,通过专门的顶点将基因组弹出.
科学领域:
- 病毒学和结构生物学
- 微生物遗传学和宿主-病原体相互作用
背景情况:
- 微病毒 (单链DNA病毒) 感染 T=1 体的细菌.
- 微型病毒的感染启动机制,特别是较大的微型病毒,人们对其了解甚微.
- 某些微病毒在哺乳动物肠道病毒中具有重要作用,并与健康疾病有关.
研究的目的:
- 阐明属于Tainavirinae亚家族的大型微型病毒Ebor的感染机制.
- 了解埃博尔的扩大囊和基因组传递系统的功能.
- 为了研究囊突起在宿主细胞附着和基因组喷射中的作用.
主要方法:
- 孤立和研究感染Rhodobacter capsulatus的微型病毒Ebor.
- 低温电子显微镜 (cryo-EM) 用于Ebor.的高分辨率结构分析.
- 低温电子断层扫描 (cryo-ET) 用于可视化感染中间体.
- 亚断层成像的平均值和单颗粒分析,以确定体的开放阶段.
主要成果:
- 埃博尔的扩大囊是由其主要囊蛋白的扩大C端产生的,可容纳化酶和甲基酶.
- 埃博尔囊上的三元突出物识别并与宿主脂多糖化合物结合,通过五个突出物介导附着.
- 囊的开放,称为"花" (penton blooming),涉及囊子单元的中央分离,使基因组能够通过专门的顶点喷射出来.
结论:
- 扩大的囊体和"花"机制促进了像Ebor.B.这样的大型微型病毒的基因组传递.
- 鉴定出的基因组喷射机制很可能在具有相似囊架构的Microviridae中得到保护.
- 了解微病毒感染为微生物群落和潜在的健康影响提供了洞察力.
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