Antiquorum sensing activity of silver nanoparticles in P. aeruginosa: an in silico study
Pseudomonas aeruginosa an opportunistic pathogen regulates its virulence through Quorum sensing (QS) mechanism comprising of Las and Rhl system. Targeting of QS mechanism could be an ideal strategy to combat infection caused by P. aeruginosa. Silver nanoparticles (AgNPs) have been broadly applied as antimicrobial agents against a number of pathogenic bacterial and fungal strains, but have not been reported as an anti-QS agent. Therefore, the aim of present work was to show the computational analysis for the interaction of AgNPs with the QS system using an In silico approach. In silico studies showed that AgNPs got ‘locked’ deeply into the active site of respective proteins with their surrounding residues. The molecular docking analysis clearly demonstrated that AgNPs got bound to the catalytic cleft of LasI synthase (Asp73-Ag = 3.1 Å), RhlI synthase (His52-Ag = 2.8 Å), transcriptional receptor protein LasR (Leu159-Ag = 2.3 Å) and RhlR (Trp10-Ag = 3.1 Å and Glu34-Ag = 3.2 Å). The inhibition of LasI/RhlI synthase by AgNPs blocked the biosynthesis of AHLs, thus no AHL produced, no QS occurred. Further, interference with transcriptional regulatory proteins led to the inactivation of LasR/RhlR system that finally blocked the expression of QS-controlled virulence genes. Our findings clearly demonstrate the anti-QS property of AgNPs in P. aeruginosa which could be an alternative approach to the use of traditional antibiotics for the treatment of P. aeruginosa infection.
KeywordsIn silico Molecular docking Quorum sensing Pseudomonas aeruginosa Virulence Silver nanoparticles
Mr. Syed Ghazanfar Ali is grateful to UGC, New Delhi, India for research assistance. Authors thank to Aligarh Muslim University, Aligarh, India and IRMC, University of Dammam, Saudi Arabia for providing instruments facilities and other items used in this study.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
This article does not contain any studies with human or animals performed by any of the authors.
- Gnanendra TS, Geethu G, Arjunan S, Sharmila B, Hussain MIZ, Moorthy K, Jeyakumar N (2010) Theoretical models of quorum sensing dependent regulation of transcriptional activators of Pseudomonas aeruginosa. Inter J Biol Technol 1:43–49Google Scholar
- Su HC, Ramkissoon K, Doolittle J, Clark M, Khatun J, Secrest A, Wolfgang MC, Giddings MC (2010) The development of ciprofloxacin resistance in Pseudomonas aeruginosa involves multiple response stages and multiple proteins. Antimicrob Agents Chemother 54:4626–4635CrossRefPubMedPubMedCentralGoogle Scholar
- Wagner VE, Filiatrault MJ, Picardo KF, Iglewski BH (2008) Pseudomonas aeruginosa virulence and pathogenesis issues. In: Cornelis P (ed) Pseudomonas genomics and molecular biology, 1st edn. Caister Academic Press, Norfolk, pp 129–158Google Scholar