一个翻译独立的定向进化策略,用于设计氨基酸-tRNA合成酶
Chintan Soni1, Noam Prywes2,3, Matthew Hall4
1Department of Chemistry, Boston College, Chestnut Hill, Massachusetts 02467, United States.
ACS central science
|July 1, 2024
概括
研究人员开发了一种新的方法,即没有核糖体翻译的tRNA激活选择平台 (START),用于设计氨基酸-tRNA合成酶 (aaRSs) 以将非正规氨基酸 (ncAA) 纳入蛋白质.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 合成生物学 合成生物学
背景情况:
- 定向进化使得氨基酸-tRNA合成酶 (aaRSs) 的工程能够结合非正规氨基酸 (ncAAs).
- 目前的选择方法依赖于记者蛋白表达,限制使用亚最佳核糖体基质.
- 需要采取两步的方法:aARS工程用于充电异国情调单体和核糖体工程用于它们的翻译.
研究的目的:
- 为aaRS工程开发一种新的平台,可以直接选择tRNA-化,而无需进行核糖体翻译.
- 克服转化依赖选择的局限性,以结合异国情调的单体.
- 为了使遗传密码能够扩展到不同的ncAAs.
主要方法:
- 开发了tRNA无核糖体翻译 (START) 系统的选择平台.
- 与具有独特序列条形码的同源tRNA相关联的不同的aaRS突变.
- 保护含有条形码的tRNA通过aARS化来防止氧化损伤,然后进行测序以识别活跃的aARS突变物.
主要成果:
- 证明了START平台在识别新型aaRS突变中的有效性.
- 成功识别了 * Methanomethylophilus alvus * pyrrolysyl-tRNA合成酶的突变体.
- 展示了使用工程aaRSs将ncAAs纳入活细胞中的蛋白质的能力.
结论:
- START平台提供了一个强大的aARS工程方法,独立于核糖体翻译.
- 这种方法有助于选择能够充电外来单体的aaRSs.
- START能够通过ncAAs扩展蛋白质组,从而推进合成生物学和蛋白质工程.
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