Cationic Homopolymers Inhibit Spore and Vegetative Cell Growth of .

A wide range of synthetic polymers have been explored for antimicrobial activity. These materials usually contain both cationic and hydrophobic subunits because these two characteristics are prominent among host-defense peptides. Here, we describe a series of nylon-3 polymers containing only cationic subunits and their evaluation against the gastrointestinal, spore-forming pathogen . Despite their highly hydrophilic nature, these homopolymers showed efficacy against both the vegetative and spore forms of the bacterium, including an impact on spore germination. The polymer designated P34 demonstrated the greatest efficacy against strains, along with low propensities to lyse human red blood cells or intestinal epithelial cells. To gain insight into the mechanism of P34 action, we evaluated several cell-surface mutant strains of to determine the impacts on growth, viability, and cell morphology. The results suggest that P34 interacts with the cell wall, resulting in severe cell bending and death in a concentration-dependent manner. The unexpected finding that nylon-3 polymers composed entirely of cationic subunits display significant activities toward should expand the range of other polymers considered for antibacterial applications.