摘要
      抗生素耐药性基因（ARGs）的全球传播，特别是通过质粒介导的水平转移，正在成为一种普遍的健康威胁。虽然我们之前的研究发现除草剂可以加速土壤细菌中ARGs的水平基因转移（HGT），但除草剂促进细菌属间和属内ARGs水平基因转移的潜在机制仍不清楚。在此，通过检测细胞内活性氧（ROS）的产生、细胞外聚合物成分、细胞膜完整性和质子原动力，结合全基因组RNA测序，分析了除草剂促进的HGT的潜在机制。除ROS反应外，暴露于除草剂诱导了一系列上述细菌反应以促进HGT，包括通过增强菌毛编码的基因表达和降低细胞表面电荷来实现细胞间的紧密接触，增加细胞膜通透性，增强质子原动力，为DNA摄取提供额外的动力。这项研究对除草剂促进细菌耐药性传播的风险提供了一种机制上的理解，为非抗生素农化加速ARGs的HGT提供了一个新的视角。
Abstract
The global dissemination of antibiotic resistance genes (ARGs), especially via plasmid-mediated horizontal transfer, is becoming a pervasive health threat. While our previous study found that herbicides can accelerate the horizontal gene transfer (HGT) of ARGs in soil bacteria, the underlying mechanisms by which herbicides promote the HGT of ARGs across and within bacterial genera are still unclear. Here, the underlying mechanism associated with herbicide-promoted HGT was analyzed by detecting intracellular reactive oxygen species (ROS) production, extracellular polymeric substance composition, cell membrane integrity and proton motive force combined with genome-wide RNA sequencing. Exposure to herbicides induced a series of the above bacterial responses to promote HGT except for the ROS response, including compact cell-to-cell contact by enhancing pilus-encoded gene expression and decreasing cell surface charge, increasing cell membrane permeability, and enhancing the proton motive force, providing additional power for DNA uptake. This study provides a mechanistic understanding of the risk of bacterial resistance spread promoted by herbicides, which elucidates a new perspective on nonantibiotic agrochemical acceleration of the HGT of ARGs.

https://www.sciencedirect.com/science/article/abs/pii/S1001074221003107