Antimicrobial poly(ionic liquid)-induced bacterial nanotube formation and drug-resistance spread

Bacterial nanotubes are tubular membranous structures bulging from the cell surface that can connect neighboring bacteria for the exchange of intercellular substances. However, little is known about the formation and function of bacterial nanotubes under the stress of antimicrobial materials. Herein, an imidazolium-type cationic poly(ionic liquid) (PIL) and corresponding PIL membranes with antimicrobial properties were synthesized. The effects of these cationic polymers on the formation of bacterial nanotubes between Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) or Vibrio fischeri (V. fischeri), followed by intraspecies and interspecies exchange of antibiotic resistance genes (ARGs) were investigated. The results showed that bacteria tend to produce more nanotubes accompanied by drug-resistance trade, which can even make the ARGs of pathogens spread to the environmental microbes of V. fischeri. Given the unique antimicrobial sustainability toward bacteria after they acquire ARGs via bacterial nanotubes, antimicrobial PILs demonstrate bright prospects in the battle against resistant bacteria.