Synthesis of antimicrobial polymers with mannose residues as binders for the FimH adhesin of Escherichia coli

Abstract

AbstractRecently, antimicrobial polymers have been developed as novel antibiotics, and they are beneficial for human health. An advantage of these polymers is that they can be easily functionalized via the addition or modification of monomers. In this study, to enhance the bacterial selectivity and antimicrobial activity of a polymer, mannose monomers were copolymerized with aminopropyl monomers and isoalkyl monomers. These mannose monomers were found to mimic the mannan and N‐glycan moieties on mammalian cells interacting with the FimH adhesin of Escherichia coli. A mannose monomer with a short ethyl linker did not enhance the antimicrobial activity (minimum inhibitory concentration (MIC): 32 μg/ml) against E. coli; however, that with a longer hexyl linker enhanced the antimicrobial activity (MIC: 16 μg/ml) against E. coli selectivity (no effect on Staphylococcus aureus was observed). Further, the polymer containing the hexyl mannose residue did not develop resistance in E. coli after 15 passages. Consequently, polymers with mannose units, which have a high affinity for the FimH adhesin, can serve as effective and selective antimicrobial agents against E. coli.