Unveiling the Barcodes of Biofilm Formation Genes (algD, pslA, pslB, and pelA) and Antibiotic Resistance Genes (bla-OXA and blaCTX-M) of Pseudomonas aeruginosa Strains Isolated from Wound Burn Infections in Iraq

Abstract

Pseudomonas aeruginosa is a common opportunistic pathogen found in burn wound infections. Multi-drug resistance, coupled with its ability to form biofilms, makes treatment outcomes even more difficult to achieve. The molecular characterization of the biofilm genes of virulence and the determinants of extended-spectrum β-lactamase (ESBL) is vital concerning the epidemiology and clinical behavior of the circulating strains. The aim of this study was to create molecular barcodes for the P. aeruginosa isolates from burn wound infections in Iraq, focusing on the biofilm formation genes (algD, pslA, pslB, and pelA) and antibiotic resistance genes (blaOXA and blaCTX-M). Clinical samples were obtained from 70 patients with burn wounds. Selective media, the VITEK 2 system, and 16S rRNA gene sequencing were used to identify 20 isolates of P. aeruginosa. ESBL-encoding genes and biofilm-related genes were detected using conventional PCR. Ten isolates were selected to represent the set, and their partial 16S rRNA sequences were analyzed for phylogenetic relationships and submitted to GenBank. The findings showed that 100% of isolates had the biofilm-forming genes algD, pslA, pslB, and pelA. The blaOXA gene was present in all the isolates examined, and blaCTX-M was present in 19 out of 20 isolates (95%). Successful amplification of gene-specific fragments showed the widespread co-occurrence of biofilm and resistance determinants. The phylogenetic analysis showed the presence of close genetic relatedness of the isolates and P. aeruginosa reference strains. The prevalence of biofilm-producing P. aeruginosa and ESBL genes in reported cases from Iraqi healthcare facilities indicates the need for focused molecular-based/incision antimicrobial management.