Herbicide promotes the conjugative transfer of multi-resistance genes by facilitating cellular contact and plasmid transfer
Shungui Zhou , Xi Li , Chang Wen , Chen Liu , Shiyun Lu , Zhongbing Xu , Qiue Yang , Zhi Chen , Hanpeng Liao
DOI:10.1016/j.jes.2021.08.006
Received June 07, 2021,Revised , Accepted August 09, 2021, Available online August 24, 2021
Volume 34,2022,Pages 363-373
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.
