The Institute of Genetic Engineering and Biotechnology for Postgraduate Studies at the University of Baghdad discussed the master’s thesis of student Sameer Adel Jawad, entitled:
“Molecular Detection and Gene Expression of Efflux Pump Genes and Virulence Factors in Pseudomonas aeruginosa Isolated from Clinical Sources”,
supervised by Professor Wathiq Abbas Al-Draghi.
The study aimed to highlight the widespread prevalence of resistance and virulence determinants in clinical isolates.
Using quantitative real-time PCR (qRT-PCR) with the fbp gene as an internal housekeeping reference, the study revealed distinct gene expression patterns across different resistance categories. Sensitive isolates showed relatively low expression levels of both virulence genes and efflux pump–related genes (ExoS: 1.18, ToxA: 0.45, MexA: 1.59, MexB: 3.64).
In contrast, multidrug-resistant (MDR) isolates demonstrated a marked increase in the expression of efflux pump genes (MexB: 6.91, MexA: 2.87, OprM: 1.45), accompanied by moderate expression of virulence genes.
The qRT-PCR analysis showed clear sigmoidal amplification curves for all target genes, indicating active transcription. Gene expression was quantified using the ΔΔCT method, and fold changes were calculated as 2^(-ΔΔCT).
The study concluded that the widespread presence of resistance and virulence genes in these clinical isolates has significant implications.
It recommended that the pervasive occurrence of the MexAB-OprM efflux pump genes indicates a high likelihood of antibiotic resistance, which could lead to treatment failure.
