在细菌中通过PAM独立的基因编辑进行一次性基因失活
Xin Li1, Ying Wei1, Shu-Yan Wang1
1School of Environmental Science and Engineering, Shandong University, Qingdao, China.
The Journal of biological chemistry
|December 20, 2024
概括
我们开发了XSTART,这是一个新的基编辑系统,可以在没有DNA断裂的情况下使细菌基因失活. 这种不受约束的系统实现了近100%的效率,并且在各种细菌物种中起作用.
科学领域:
- 合成生物学 合成生物学
- 微生物遗传学微生物遗传学
背景情况:
- 基组编辑在细菌中提供了精确的基因修改,没有双链断裂.
- 目前的基础编辑系统受到原始空间相邻图案 (PAM) 和编辑窗口限制的限制.
- 有效的基因失活对于代谢工程和细菌的功能基因组学至关重要.
研究的目的:
- 开发一种不受约束的基编辑系统,用于普遍的细菌基因失活.
- 为了克服PAM依赖和编辑窗口在现有基础编辑器中的局限性.
- 建立一种高效的方法来制造辅助性细菌菌株.
主要方法:
- 通过使用dCas9衍生物 (dSpRY) 和激活诱导的cytidine deaminase,设计了一个与protospacer相邻的基因独立基因编辑器.
- 编程基础编辑器以准和排除用于基因失活 (XSTART) 的START编码子.
- 应用了XSTART来操纵大肠杆菌中的氨基酸代谢,并对大肠杆菌Nissle 1917和Synechococcus elongatus进行了测试.
主要成果:
- 使用XSTART系统实现了近100%的基因失活效率.
- 在大肠杆菌中成功生成了谷氨酸,氨酸和酸的辅助性菌株.
- 通过完善XSTART的监管系统,在不影响效率的情况下,减少了超过60%的目标事件.
结论:
- XSTART为细菌基因失活提供了一种多功能和高效的工具,克服了以前的局限性.
- 该系统在不同的细菌物种中展示了广泛的适用性,包括益生菌和光合作用菌株.
- 在合成生物学和代谢工程中,XSTART对细菌重编程具有显著的潜力.
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