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一种SelB变异的定向进化,它不需要单半氨酸插入序列元件来发挥功能

Satoshi Ishida¹, Arno Gundlach¹, Clayton W Kosonocky¹

¹Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas 78712, United States.

ACS synthetic biology

|June 19, 2025

概括

研究人员开发了一种独立于SECIS的单半氨酸延长因子 (SelB-v2),该因子将单半氨酸纳入停止编码子. 这种工程蛋白还可以重新用于其他氨基酸,扩大遗传密码的可能性.

科学领域:

分子生物学分子生物学
生物化学生物化学
合成生物学合成生物学

背景情况:

在细菌中结合单半氨酸通常需要单半氨酸特异延长因子 (SelB),单半氨酸充电tRNA^Sec,以及一个SECIS元素.
由于的高核友性和disenenide键的稳定性, SECIS 独立的氨基结合是可取的.
进化起源表明,单半氨酸插入可能最初没有SECIS元素发生,仅依赖SelB.

研究的目的:

为了进化SelB蛋白的祖先,SECIS独立版本.
通过使用进化后的SelB.来研究氨基在停止编码子中的一般化结合.
探索将这个直角转化因子重新用于其他氨基酸的潜力.

主要方法:

为了实现SECIS独立性,SelB蛋白的实验进化.
测试进化的SelB (SelB-v2) 在mRNA中停止编码子中结合单半氨酸的能力.
测试SelB-v2的重新用途,以结合替代氨基酸,如血清素.

主要成果:

成功演化了一个SECIS独立的SelB变体 (SelB-v2).
证明SelB-v2通常可以结合相反的停止编码子的单半氨酸.
表明SelB-v2可以重新使用,以结合其他氨基酸,如氨酸,创建一个直角转化系统.

结论:

经过工程设计的SelB-v2蛋白使得一般化,独立于SECIS的类固醇结合成为可能.
这项工作验证了使用基于SelB的直角翻译来扩展遗传密码的可能性.
这些发现为设计大大扩展的基因代码,利用基于SelB的氨基酸加载,打开了道路.

关键词:

这就是 SECISIS.这就是 SelB SelB 的意思.指导进化是指导进化的.遗传代码重编程遗传代码重编程单半氨酸是一种单半氨酸.

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