翻译抑制剂kasugamycin,edeine和GE81112在30S启动复合物形成过程中针对不同的步骤
Haaris A Safdari1, Martino Morici1, Ana Sanchez-Castro2
1Institute for Biochemistry and Molecular Biology, University of Hamburg, 20146, Hamburg, Germany.
Nature communications
|March 13, 2025
概括
三种抗生素通过与30S核糖体子单元的E位点结合来抑制细菌的翻译启动. 卡苏加素,埃丁和GE81112揭示了影响启动复合体形成和因子离开的独特机制.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 微生物学 微生物学
背景情况:
- 细菌翻译启动对于蛋白质合成至关重要,涉及30S核糖体亚单元,启动因子和启动tRNA.
- 卡苏加米辛,埃丁和GE81112是已知的这种过程的抑制剂,但它们的确切机制尚不清楚.
研究的目的:
- 阐明克苏加素,埃丁和GE81112抑制细菌翻译启动的分子机制.
- 确定抗生素与30S核糖体启动复合体相互作用的结构基础.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 来确定30S启动中间复合体的高分辨率结构 (2.0-2.9 Å).
- 这些复合物是在kasugamycin,edeine和GE81112的存在下形成的.
主要成果:
- 发现这三种抗生素都与30S子单元的E位点结合,防止30S启动复合物的形成.
- 卡苏加米辛和埃迪因干扰30S预启动复合体组装的早期阶段.
- GE81112允许启动编码子识别,但阻止了启动因子IF3的离开,在以后的步骤中阻止了复杂的形成.
结论:
- 化学上不同的抗生素可以通过独特的机制通过结合30S核糖体子单元的保存部位来抑制细菌的翻译启动.
- 了解这些机制,可以了解针对蛋白质合成的新型抗菌策略.
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