Molecular Identification of lasB gene in Pseudomonas Aeruginosa Isolated From Patients With Urinary Tract Infection


  • General directorate of Thi-Qar education , Ministry of Education, Thi-Qar, Iraq
  • Department of science, The Open Educational College, Ministry of Education, Iraq


Background: Pseudomonas aeruginosa is an opportunistic pathogen capable of infecting various body
sites due to the presence of multiple virulence factors that significantly contribute to disease. This study
aimed to assess the antibiotic susceptibility of P. aeruginosa isolates, detect the frequency of the lasB
gene in clinical isolates, furthermore analyze the genetic sequence and the resulting mutations.
Materials and Methods: A total of 120 samples were collected from patients with urinary tract
infections (UTIs) during the period from November 2021 to March 2022. The specimens identified using microbiological and biochemical tests, as well as the VITEK2 system, and confirmed by PCR using specific primers. Gene sequence analysis was conducted by aligning the sequences with those in the gene bank using the Blast alignment program. Antibiotic sensitivity testing of Pseudomonas aeruginosa
isolates was performed using the Kirby-Bauer method.
Results: Out of the 120 samples, 18 were positive for P. aeruginosa isolates. The infection rate was
higher in females (88.8%) compared to males (11.2%). The highest resistance rate was observed for
Levofloxacin (38%), while Piperacillin/Tazobactam and Meropenem showed the lowest resistance rates
(11% each). The lasB gene was detected in all 18 isolates, and gene sequence analysis confirmed their identity as P. aeruginosa, matching the reference sequence in the gene bank. The gene sequence analysis
of the lasB gene revealed the presence of five mutations,
Conclusions: This study demonstrated that Pseudomonas aeruginosa possesses several virulence factors,
including the lasB gene. Sequencing analysis of the lasB gene revealed the presence of multiple


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