Beta‐lactamase‐producingPseudomonas aeruginosa: Phenotypic characteristics and molecular identification of virulence genes. Issue 3 (March 2017) - Ullah, Waheed
Abstract : Background : Pseudomonas aeruginosa causes common infections in immunocompromised and cystic fibrosis patients. However, drug resistance capability and release of virulence factors play a key role in bacterial pathogenicity. Methods : Beta‐lactamase‐producing clinical isolates of P. aeruginosa were screened for biofilm formation and pigment production. Subsequently, all the isolates were subjected to the detection of six virulence genes ( OprI, OprL, LasB, PlcH, ExoS, and ToxA ). Results : Among beta‐lactamase‐producing isolates ( n = 54), about 85.18% ( n = 46) were biofilm producers. Pigment production was observed in 92.59% ( n = 50) isolates. Clinical samples were subsequently screened for detection of virulence factors. Among them, 40.74% ( n = 22) isolates were found to be OprI positive, while 29.62% ( n = 16) were OprL producers. In the case of LasB and PlcH, 24% ( n = 13) and 18.5% ( n = 10) isolates produced these virulence genes, respectively. Among the isolates, 37.03% ( n = 20) and 33.33% ( n = 18) expressed virulence factors ExoS and ToxA, respectively. Furthermore, 42.59% ( n = 23) isolates coproduced more than one type of virulence factors. Conclusion : In the current study, pigment display, biofilm formation, and virulence genes were detected in P. aeruginosa clinical isolates. Such factors could be crucial in the development of drug resistance.