In silico identification of quorum sensing inhibitors against LasR protein in a clinical isolate of multidrug resistant Pseudomonas aeruginosa DMC-27b

Abstract

Background: Pseudomonas aeruginosa is an opportunistic pathogen that uses quorum-sensing (QS) and biofilm formation to subvert antibiotic therapy. Antibiotic resistance has led to a demand for alternative methods of treatment, and destabilizing the LasR-OdDHL binding with inhibitors offers a potential solution. Methods: This study aimed to construct a homology model of the LasR protein using the genetic sequence of the P. aeruginosa DMC-27b strain (GenBank: SMRY00000000.2). Molecular docking, molecular mechanics-based binding free energy calculation, and pharmacokinetic analysis were performed on 1900 3D structures collected from synthetic and natural compound databases to identify three potential lead molecules. These compounds were evaluated using ADMET (absorption, distribution, metabolism, excretion, toxicity) analysis, and molecular dynamics protocols were used to refine the results. Results: The three lead compounds showed higher binding capability with the LasR receptor than the native ligand and passed the ADMET evaluation stage. In total, 44 properties remained within the range of 95% of known drugs, indicating their potential efficacy as drugs against P. aeruginosa and other bacteria that use a similar QS system. Conclusions: This study provides insights into potential drug designing and development against clinical isolates of emerging P. aeruginosa strains and other bacteria that use a similar QS system.