Environmental concentrations of acetaminophen and its metabolites promote the spread of antibiotic resistance genes through pheromone signaling pathway

Abstract

The massive use of acetaminophen (APAP), an antipyretic and analgesic drug, especially during the COVID-19 pandemic, has caused the environmental residue and pollution of acetaminophen and its metabolites. However, the environmental ecological and health issues they may cause are still unclear. In this study, we found that environmental concentrations of APAP and its metabolites could promote the conjugative transfer of antibiotic resistance genes mediated by plasmid pCF10 through pheromone-like effect rather than the commonly mechanism found in current studies. Conjugative transfer studies showed that APAP and its metabolites increased the frequency of conjugative transfer of ARGs by up to 3.3 times, reaching 3.2 × 10-2. We explored the underling mechanisms using qPCR, western blot, and SEM images. This study demonstrates that APAP stimulates pheromone secretion, subsequently triggering conjugation and accelerating downstream gene expression. Furthermore, APAP functions as a pheromone, initially facilitating plasmid cleavage and peptidoglycan hydrolysis, followed by the promotion of adhesion protein PrgB expression and T4SS scaffold construction, ultimately enhancing DNA strand transfer via T4CP. This study provides a theoretical basis for understanding the environmental hazards of APAP and the environmental sustainability.