LAUSR

ABSTRACT Pseudomonas spp. is an opportunistic pathogens that can cause an arrays of diseases for human especially wound infections. It is success can be attributed to many virulence factors which leads to adaptation and withstand for different inconvenient niches. It is also wildly spread in environment and isolated from different samples. This present study intended to display the difference in the most important virulence traits (TypeIII exotoxins) of Pseudomonas spp. among clinical and environmental isolates. Thirty eight Pseudomonas spp. isolates were used in This study. Eighteen isolates were recovered from wound infections (clinical isolates) and eighteen isolates were recovered from sewage and soil (environmental isolates) during a period of 3 months. All isolates inoculated on Pseudomonas chromogenic agar for primary screening of Pseudomonas spp. and then confirmed by PCR using specific primer for 16S rDNA gene of Pseudomonas spp. The results revealed that 17 (73.7%) and 8(42.1%) of isolates have exoS gene in clinical and environmental isolates respectively while 17 (89.5%) of clinical and 17 (89.5%) of environmental Pseudomonas spp. isolates have exoT gene. For exoU gene the results showed it is presence in all (19(100%) clinical isolates while present in only 18(94.7%) of environmental isolates. Only 12(63.2%) and 8(42.1%) of clinical and environmental isolates respectively have exoY. Our study not settle a significant differences between the virulence of clinical and environmental Pseudomonas spp. isolates and this is may indicate that the source of many environmental Pseudomonas spp. isolates may be from the medical waste or due to leakage from untreated municipal waste water.