β-氨基酸降低三元复合体的稳定性,并改变翻译延长机制
F Aaron Cruz-Navarrete1,2, Wezley C Griffin1,2, Yuk-Cheung Chan3
1Department of Structural Biology, St Jude Children's Research Hospital, Memphis, Tennessee, USA.
bioRxiv : the preprint server for biology
|March 11, 2024
概括
将非天然氨基酸 (nnAAs) 纳入蛋白质是新疗法的关键. 然而,nnAA骨干结构显著影响蛋白质合成效率和核糖体利用率,为发展创造瓶.
科学领域:
- 生物化学和分子生物学
- 合成生物学 合成生物学
- 蛋白质工程是指蛋白质工程.
背景情况:
- 使用非天然氨基酸 (nnAAs) 的模板蛋白质合成为治疗药物和材料提供了扩大的化学多样性.
- 目前的方法在可以纳入的nnAA的数量和类型方面存在局限性.
- 了解nNAA如何影响蛋白质合成机制对于克服这些局限性至关重要.
研究的目的:
- 研究nnAA单体骨干和侧链对三元复合体形成和核糖体利用的影响.
- 阐明nNAA如何扰乱mRNA模板蛋白质合成的机制.
主要方法:
- 使用集体和单分子光共振能量转移 (FRET) 测量.
- 研究了涉及氨基酸转移RNA (aa-tRNA),延长因子 (EF-Tu) 和GTP的三元复合形成.
- 评估了nnAA充电tRNAs的核糖体利用率.
主要成果:
- 氨酸 (Phe) 的 (R) 和 (S) -β2异构体都严重破坏了三元复合体的形成.
- (R) 和 (S) -β3-Phe异构体降低了三元复合体的稳定性,并且被核糖体低效地利用.
- 对特定的nnAA异构体观察到EF-Tu亲缘关系,校对和基质转位的缺陷.
结论:
- 非天然的氨基酸可以阻碍蛋白质翻译机制的多个阶段.
- 三级复合物形成的效率和稳定性是纳米亚胺酸的整合的关键瓶.
- 未来的努力必须考虑nnAA对改善蛋白质合成的翻译机制的影响.
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