Molecular and insilico Screening of RND-Type Efflux Pump oprJ Gene in Multidrug-Resistant Pseudomonas aeruginosa Isolated from Burn Patients

Background: The oprJ gene in Pseudomonas aeruginosa encodes a component of the MexCD-OprJ efflux pump, contributing to multidrug resistance. Objective: This study aimed to perform molecular and in silico analyses of oprJ, investigate mutations in antibiotic-resistant strains, examine the relationship between amino acid changes and resistance, determine the three-dimensional efflux pump structure, and identify potential inhibitors. Methodology: A total of 140 burn patient swabs were collected, identified, and tested for antimicrobial susceptibility using the VITEK 2 system. DNA from isolates was extracted, amplified by PCR, sequenced by Macrogen (Korea), translated into proteins, and analyzed via bioinformatics to model 3D structures and identify potential efflux pump inhibitors. Results: Out 140 specimens, 118 (84.3%) were culture-positive, including 60 (50.8%) P. aeruginosa, while 22 (15.7%) showed no growth. Isolates were susceptible to colistin (78%). The oprJ gene was detected in 30 isolates (50%), showing 98% sequence and 99% protein similarity to global strains. Structural analysis revealed leucine-to-methionine mutation at position 317. Molecular docking identified natural and synthetic compounds with strong efflux pump binding, evaluated by Lipinski’s Rule of Five. Statistical analysis indicated significant correlations between mutations and antibiotic resistance (P ≤ 0.05, P ≤ 0.01). Conclusion: P. aeruginosa was the predominant pathogen, with Marked resistance to antibiotics, Mutations included transversion and transition substitutions, causing amino acid changes (Tyrosine-to-Phenylalanine at P415, P520; Leucine-to-Methionine at 467; Leucine-to-Glutamine at 535; Tyrosine-to-Cysteine at 441). Conserved and variable residues were observed, and molecular docking suggested that curcumin, palmatine, berberine, and PAβN could serve as potential efflux pump inhibitors.