Inhibition of biofilm formation and virulence factors production in Pseudomonas aeruginosa PAO1 by vitamin E

Introduction and Objectives: Pseudomonas aeruginosa, a common Gram-negative bacterium in hospital-acquired infections, is an opportunistic human pathogen that exhibits intrinsic multi-drug resistance and causes death in many burn victims, cystic-fibrosis and neutropenic cancer patients. It is known that P. aeruginosa biofilm maturation and production of cell-associated and extracellular virulence factors are under the control of a quorum-sensing (QS) system. Among several proteins involved in the P.aeruginosa QS network, LasR, PqsR and RhlR play an important role in its cascade signaling system. In this research, vitamin E used as an antibacterial agent for the first time, based on the structure similarity with PqsR ligand, called PQS. Materials and Methods: Effect of Vitamin E was investigated in both biofilm formation and virulence factors production including pyoverdine, pyocyanin and protease. The effect of vitamin on other major QS pathways was also evaluated. Moreover, the compounds used in combination with tobramycin to estimate whether its activity enhanced against P. aeruginosa. Finally, in silico docking analysis was performed to assess possible interactions. Results: Vitamin E not only suppress biofilm formation but inhibit virulence factors and homoserine lactones (HSLs) production as the main components in other QS pathways of P. aeruginosa. Vitamin E also showed synergistic effect with tobramycin against the pathogen. Conclusion: This is the first report on anti-QS and anti-biofilm activity of vitamin E. These findings suggest that vitamin E can be used as potential inhibitors to control P. aeruginosa pathogenicity.

کلیدواژه ها:

Vitamin E ، Biofilm ، Pseudomonas aeruginosa ، Quorum sensing ، PqsR