Cylindrospermopsin enhances the conjugative transfer of plasmid-mediated multi-antibiotic resistance genes through glutathione biosynthesis inhibition

Cylindrospermopsin (CYN), a cyanobacterial toxin, can significantly enhance the conjugative transfer of RP4 plasmid in Escherichia coli genera at environmental levels (0.1-100 μg/L). This increase in oxidative stress in bacterial cells leads to ROS overproduction, upregulation of antioxidant enzyme-related genes, inhibition of glutathione synthesis, and increased cell membrane permeability. These findings suggest CYN’s potential impact on the spread of antimicrobial resistance in water environments.