Chlorpyrifos And Chlorpyrifos-methyl Can Promote Conjugative Transfer of Antibiotic Resistance Genes

Abstract

Antibiotic misuse induces the production of antibiotic resistance genes (ARGs), leading to the global spread of antimicrobial resistance (AMR), which poses a major threat to human health. Conjugative transfer, as the main process of ARGs propagation, is sensitively influenced by coexisting contaminants. Chlorpyrifos and chlorpyrifos-methyl, as organophosphorus insecticides widely used in agriculture, have been shown to induce cytotoxicity such as elevated levels of reactive oxygen radicals (ROS) and lipid peroxidation. This is similar to the mechanism by which antibiotics promote the conjugative transfer of ARGs, based on which we hypothesized that chlorpyrifos and chlorpyrifos-methyl could promote conjugative transfer. However, the effect of chlorpyrifos and chlorpyrifos-methyl on conjugative transfer is unclear. Therefore, we constructed RP4 plasmid-mediated conjugation system and confirmed that chlorpyrifos and chlorpyrifos-methyl can promote conjugative transfer by inducing oxidative stress in donor and recipient bacteria. Our research reveals the risk of ARM spread in organophosphorus insecticides and ARGs co-contaminated environments.