Isoeugenol suppresses multiple quorum sensing regulated phenotypes and biofilm formation of Pseudomonas aeruginosa PAO1.

The potential strategy to prevent bacterial pathogenicity is disabling quorum sensing circuits with structural mimicking molecules. Here, we analyzed a synthetic molecule isoeugenol, for inhibition of quorum sensing regulated phenotype and biofilm formation. Isoeugenol was an effective inhibitor, i.e., more than 70% of virulence factors were inhibited including pyocyanin, rhamnolipid, exopolysaccharide, swarming motility and biofilm formation. Interestingly, these quorum sensing regulated phenotypes in Pseudomonas aeruginosa PAO1 were inhibited without affecting the planktonic cells. Moreover, the presence of isoeugenol exhibited more than 70% inhibition of biofilm formation through inhibition of the quorum sensing systems. Furthermore, docking studies suggest that isoeugenol bound to the quorum sensor regulators such as LasI, LasR PqsE and SidA with considerable binding interactions. Our results demonstrate the utility of isoeugenol as a blocker of quorum sensing, which will be functioning as an antivirulence compound.