应用Φ29正交复制系统在大肠杆菌中进行高突变性连续进化，这一成果由英国剑桥医学研究委员会分子生物学实验室Jason W. Chin小组经过不懈努力而取得。相关论文于2026年2月24日发表在《自然—生物技术》杂志上。

该研究团队在大肠杆菌中开发并优化了一个正交DNA复制系统，该系统以噬菌体Φ29为主题。最小的系统需要两个Φ29基因来维持复制子，并且复制子可以在体内有效地进行工程设计。研究小组产生了一种高度诱变的Φ29 DNA聚合酶，它以接近10每代4个碱基（每10代1 kb基因发生一次突变）。它们的系统可以稳定数百代，并使新基因功能的持续加速进化成为可能。课题组人员证明了四环素耐药基因的快速进化，使其对替加环素的耐药水平高于先前报道的系统。课题组人员进一步发现，第三代头孢菌素在3天内β-内酰胺酶活性增加了1000倍。

据悉，允许靶基因高度突变而不发生宿主基因组脱靶突变的生物体，能够加速基因的持续进化，以获得新的或增强的功能。

附：英文原文

Title: Highly mutagenic continuous evolution in E.coli using a Φ29-based orthogonal replication system

Author: Rehm, Fabian B. H., Liu, Kim C., Tian, Rongzhen, Chin, Jason W.

Issue&Volume: 2026-02-24

Abstract: Organisms that permit hypermutation of target genes without off-target mutagenesis of the host genome enable the accelerated, continuous evolution of genes for new or enhanced functions. We develop and optimize an orthogonal DNA replication system in Escherichia coli that uses components from bacteriophage Φ29. The minimal system requires just two Φ29 genes to maintain the replicon and replicons can be efficiently engineered in vivo. We generate a highly mutagenic Φ29 DNA polymerase that introduces mutations at a frequency approaching 104 per base per generation (one mutation in a 1-kb gene every ten generations). Our system is stable for hundreds of generations and enables the continuous, accelerated evolution of new gene functions. We demonstrate the rapid evolution of a tetracycline resistance gene to confer resistance to tigecycline at higher levels than achieved with previously reported systems. We further evolve a 1,000-fold increase in β-lactamase activity for a third-generation cephalosporin in just 3days.

DOI: 10.1038/s41587-025-02944-x

Source: https://www.nature.com/articles/s41587-025-02944-x