摘要

转化是细菌中水平基因转移（HGT）的一种模式，其中细胞外裸DNA被具有发育遗传能力的细胞摄取。对降解裸DNA的DNase的敏感性是区分转化与DNase抗性HGT机制的关键。一般来说，大肠杆菌不被认为是天然可转化的;它仅在人工条件下发展出高能力，包括暴露于高Ca2 +浓度。然而，据报道，在实验室以外的自然环境中可行的某些条件下，大肠杆菌可以表达适度的能力。此外，最近的数据表明环境因素影响多种转化途径。在这篇小型综述中，我们（1）总结了我们使用大肠杆菌实验系统进行基于转化的HGT的研究，以及（2）通过环境中的多种机制讨论可能发生的转化及其对抗生素抗性基因扩散的可能影响。

Transformation is one mode of horizontal gene transfer (HGT) in bacteria, wherein extracellular naked DNA is taken up by cells that have developed genetic competence. Sensitivity to DNase, which degrades naked DNA, is the key to distinguishing transformation from the DNase-resistant HGT mechanisms. In general, Escherichia coli is not believed to be naturally transformable; it develops high competence only under artificial conditions, including exposure to high Ca2+ concentrations. However, E. coli can reportedly express modest competence under certain conditions that are feasible in natural environments outside laboratory. In addition, recent data suggest that environmental factors influence multiple routes of transformation. In this mini review, we (1) summarize our studies on transformation-based HGT using E. coli experimental systems and (2) discuss the possible occurrence of transformation via multiple mechanisms in the environment and its possible impact on the spread of antibiotic resistance genes.

https://www.ncbi.nlm.nih.gov/pubmed/30337917