Alantolactone modulates the production of quorum sensing mediated virulence factors and biofilm formation in Pseudomonas aeruginosa

Pseudomonas aeruginosa is an opportunistic pathogen in immunocompromised patients and accounts for mortality worldwide. Quorum sensing (QS) and QS mediated biofilm formation of P. aeruginosa increase the severity of infection in the host. New and effective therapeutics are in high demand to eliminate Pseudomonas infections. The current study investigated the quorum quenching and biofilm inhibition properties of alantolactone (ATL) against P. aeruginosa PAO1. The production of key virulence factors and biofilm components were affected in bacteria when treated with sub-MIC of ATL and further validated by qRT-PCR studies. The anti-infective potential of ATL was corroborated in an in vivo model with improved survival of infected Caenorhabditis elegans and reduced bacterial colonization. In silico studies suggested the molecular interactions of ATL to QS proteins as stable. Finally, ATL was explored in the present study to inhibit QS pathways and holds the potential to develop into an effective anti-infective agent against P. aeruginosa.