PCR based identification of exotoxin A-producing Pseudomonas aeroginosa isolated from burn wound infection

Document Type : Original Article


1 Department of Pharmacology and Toxicology, School of Pharmacy, Zanjan University of Medical Sciences, Zanjan, Iran.

2 Department of Pharmacology and Toxicology, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz, Iran

3 Infectious Diseases and Tropical Medicine Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran

4 Social Determinants of Health Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

5 Department of Clinical Toxicology, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

6 Department of Biochemistry and Nutrition, Faculty of Medicine, AJA University of Medical Sciences, Tehran, Iran.

7 Department of Food Quality Control Laboratory, Army Health Center of Excellence (NEZAJA), Tehran, Iran

8 Department of Education and Research, Army Health Center of Excellence (NEZAJA), Tehran, Iran

9 Department of Environmental Health Engineering, School of Public Health, Sabzevar University of Medical Sciences, Sabzevar, Iran


Exotoxin A (exoA) is a major pathogenic factor in Pseudomonas aeruginosa. This non-fermenting gram-negative bacillus causes a wide range of infections. P. aeruginosa is a major cause of hospital-acquired infections. With this view, this study was aimed to identify P. aeruginosa strains carrying the exoA gene isolated from burn wounds. As part of the cross-sectional study, 110 samples of burns were collected in several hospitals. After identification of bacterial strains by biochemical and microbiological tests, genomic DNA was extracted. PCR reaction was performed for screening for exoA gene. After examining DNA extracted using quantitative (Nano drop with OD260/280=1.8-2nm) and qualitative (electrophoresis on the 0.7% gel agarose) methods, 75.4% (n; 83 of 110) isolates carried the exoA gene. The high prevalence of the exoA gene in P. aeruginosa strains indicate the important role of this exoenzyme in the spread of infection in burn patients. Therefore, it is recommended that people with burn infections be screened for the exoA gene.
Please cite this article as: Gholamreza Morshedi, Vahid Ghanbarinejad, Mina Zarei, Abazar Pournajaf, Hossein
Hassanian-Moghaddam, Vahid Hadi,Abbas Isvand, Mohammad Reza Saadati, Homayoun Maleki, Majid Keshavarzi. PCR based identification of exotoxin A-producing Pseudomonas aeroginosa isolated from burn wound infection. Trends in Pharmaceutical Sciences. 2022;8(1):51-56 .doi: 10.30476/TIPS.2021.93218.1121


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