Curcumin, a known phenolic from curcuma longa, attenuates the virulence of Pseudomonas aeruginosa PAO1 in whole plant and animal pathogenicity models

摘要

The effect of curcumin on the virulence of Pseudomonas aeruginosa (PAO1) using whole plant and animal pathogenicity models was investigated. The effect of curcumin on PAO1 virulence was studied by employing in vitro assays for virulence factor production, Arabidopsis thaliana/Caenorhabditis elegans pathogenicity models, and whole genome microarray analysis. It is shown that the curcurnin inhibits PAO1 virulence factors such as biofilm formation, pyocyanin biosynthesis, elastase/protease activity, and acyl homoserine lactone (HSL) production. As a consequence of this, curcurnin treatment resulted in the reduced pathogenicity of P. aeruginosa-C. elegans and P. aeruginosa-A. thaliana infection models. In addition, transcriptome analysis of curcurnin-treated PAO1 revealed downregulation of 31 quorum sensing (OS) genes, of which many have already been reported for virulence. The supplementation of HSLs along with the curcurnin treatment resulted in increased pathogencity and recovery of higher bacterial titers in a plant pathogenecity model. These data reveal the involvement of curcurnin in QS interruption to reduce pathogenicity. Curcumin attenuates PA01 virulence by down-regulation of virulence factors, QS, and biofilm initiation genes. The effect of curcurnin on multiple targets such as virulence, QS, and biofilm initiation makes curcurnin a potential supplemental molecule for the treatment of P. aeruginosa infections.