Molecular Analysis of Pathogenic Genes (lasB and exoA) in Pseudomonas aeruginosa Strains Isolated from Animal and Human Samples and Determination of Their Resistance Pattern

Abstract

: Pseudomonas aeruginosa (P. aeruginosa) has a wide range of virulence factors. These factors have the potential to increase bacterial pathogenicity and serious infection. The purpose of this study was to evaluate the virulence profiles and antibiotic susceptibility of isolates of P. aeruginosa originated from animal and human samples. The samples were cultured on selective media before being extracted for DNA and subjected to a PCR technique to detect virulence genes. There was a significant difference in the isolation of P. areuginosa isolated from human and animal sources. Where, in humans, the percentage of P. areuginosa was 52 (68.42%) while in animals the percentage of P.aeruginosa was 24 (31.57%). In humans, the percentage of P. aeruginosa in blood was 26.92% (14 isolates), in urine it was 25% (13 isolates), in wound it was 40.38%21 isolates), and in sputum it was 7.69% (4 isolates). We used a PCR technique that produced highly specific and accurate results for detecting virulence factor genes in P. aeruginosa isolates that cause disease in humans and animals. The percentage of exoA genes was (83.33%) and (81.66%) in the animal and human, and that of lasB was (58.33%) and (92.30%) in animal and human samples respectively. Furthermore, both the exoA and lasB genes are found in 26.31% of animal strains and 17.10% of human strains. The disc diffusion method was used to determine antimicrobial susceptibility. In both animal and human isolates, P. aeruginosa showed the highest resistance to amikacin and the lowest resistance to ciprofloxacin. These findings could aid in the understanding of pathogenicity processes, treatment direction, and the development of strategies to control the spread of epidemic P. aeruginosa strains.

Experimental Study of Pathological and Some Immunological Aspect of Infection Pseudomonas aeruginosa bacteria and Exotoxin in Rabbits

“…Exotoxin A extraction: This procedure was described by (13) for the extraction of exotoxin A from P. aeruginosa isolates, stock cultures were streaked on Trypticase Soya Agar (TSA) and incubated overnight at 30°C. The isolated colonies were picked, streaked on Trypticase Soya Agar (TSA) slants, and incubated overnight, the growth was suspended in Trypticase Soya Broth which contained 15% (v/v) glycerol and was stored in aliquots at -70°C.…”