Transcriptional profiling ofPseudomonas aeruginosaPAO1 in response to anti-biofilm and anti-infection agent exopolysaccharide EPS273

Aims Relatively, few anti-biofilm polysaccharides againstPseudomonas aeruginosawere done to investigate the underlying molecular mechanism. Exopolysaccharide EPS273 can clearly reduce biofilm formation and infection ofP. aeruginosa. This study aims to investigate its anti-biofilm and anti-infection mechanism on transcriptional level. Methods and Results Herein, we used an RNA-Seq transcriptomic approach to investigate the underlying anti-biofilm and anti-infection mechanism of EPS273. The expression levels of a large number of genes were changed afterP. aeruginosaPAO1 was treated with EPS273. Especially, the genes related to biofilm formation, such as gene involved in production of extracellular matrix and virulence factor, genes involved in flagella and cell motility and genes involved in iron acquisition. Notably, the expression levels of genes involved in regulatory and signal transduction were markedly downregulated, such as two-component system PhoP-PhoQ and quorum sensing (QS) system LasI/LasR and RhlI/RhlR. Furthermore, when genesphoPandphoQwere disrupted, respectively, the reduction of biofilm formation and cell motility in mutant ophoPor ophoQwas also detected. Conclusion EPS273 may exert its anti-biofilm and anti-infection function by downregulating gene expression of two-component system PhoP-PhoQ and QS systems LasI/LasR and RhlI/RhlR ofP. aeruginosa, which further regulated expression of genes involved in biofilm formation. Significance and Impact of the Study Our data will expand understanding of anti-biofilm mechanisms of polysaccharides on transcriptomic level.

Automated summary

This study investigated the anti-biofilm and anti-infection mechanism of EPS273 on a transcriptional level using an RNA-Seq approach. The results showed that EPS273 can reduce biofilm formation and infection of P. aeruginosa by downregulating the expression of the PhoP-PhoQ and QS systems.