Efficacy of Artesunate againstPseudomonas aeruginosaBiofilm Mediated by Iron

Abstract

Pseudomonas aeruginosais capable of causing a variety of chronic infections due to the formation of biofilms. Iron is essential for growth ofPseudomonas aeruginosa, and therapies that interfere with iron may help treatP. aeruginosainfections. Herein, we investigated whether artesunate, which is a type of iron-dependent drug, could influencePseudomonas aeruginosabiofilm formation and structure, including the underlying mechanisms. Artesunate could enhance twitching motility significantly and decrease the proportion of surviving cells inPseudomonas aeruginosabiofilms in a dose-dependent manner. Artesunate treatment also reduced biofilm thickness, diffusion in the biomass, and the content of Fe(II). However, changes in biofilm structure and ion concentration were very similar following treatment with 512 μg/ml and 1024 μg/ml artesunate. Interestingly, both biofilm structure and surviving cell fraction were recovered after iron supplementation. These results suggest that artesunate interferes withPseudomonas aeruginosabiofilms by decreasing bacterial viability and enhancing twitching motility in an iron-independent manner.