Abstract

Pseudomonas aeruginosa is an opportunistic bacterium that synthesizes multiple virulence factors. This research assessed the comparative prevalence of exoenzymes (exo) A, U, and S genes (II and III). In the present study, a total of 120 specimens were obtained from different hospitals in Babylon, Iraq and collected from different sources including burn, wound, urine, ear and sputum. The results showed that 42 (35 %) of isolates were P. aeruginosa isolates, distributed to 33 burn (78.5%), ear and urine 3 (7 %) , 2 wound (4.7%) and one sputum (2.3%). Class II and III virulence genes were identified using a PCR test on extracted DNA. The Type III Secretion System (T3SS) is crucial for the direct translocation of effector proteins into target cells of the host via a needle-like apparatus. The PCR findings indicated that 41 (97.6%) P. aeruginosa isolates were positive for the ToxA gene, 40 (95%) for the exoS gene, and 39 (92.5%) for the exoU gene. According to the categorization of virulence genes, the count of invasiveness gene-isolates was 40 for the exoS gene (95%), which is somewhat higher than the cytotoxic gene-isolates at 39 for the exoU gene (92%). The findings indicated a statistically significant correlation (p<0.05) between virulence genes and T3SS genotypes; however, the prevalence of the ToxA gene was much greater among the cytotoxic genotype isolates. The statistical analysis of the current investigation indicated a strong correlation between the presence of the exotoxin genes exoS, exoU, and ToxA with resistance to various antibiotic classes (P? 0.05). This study sought to find the pathogenicity genes. The quantity of isolates possessing the invasive gene (exoS) was marginally greater than that of those containing the cytotoxicity gene (exoU).

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