Rapid identification of Pseudomonas aeruginosa by pulsed-field gel electrophoresis

Abstract

Twenty clinical Pseudomonas aeruginosa isolates recovered from patients admitted to The General Hospital in Ismailia Governorate (Egypt) were examined in this study. We analysed P. aeruginosa ATCC 9027 (as a control strain) and 19 of the isolates after digestion with SpeI restriction endonuclease. After this we conducted a pulsed-field gel electrophoresis (PFGE) and typed the obtained 10 unique patterns, designated as A, A1, B, B1, C, C1, D, D1, E and F. We evaluated the genetic relatedness between all strains, based on ≥87% band identity. As a result, the isolates were grouped in the 10 clusters as follows: patterns A, A1, B, B1, C contained two strains each and patterns C1, D, D1, E contained a single strain each; the five remaining strains were closely related (genomic pattern F). One isolate belonged to antibiotype ‘b’. The genotype patterns of the P. aeruginosa ATCC 9027 control strain and isolate no. 11 were closely related and had two different antibiotypes ‘d’ and ‘c’, respectively.

Keywords:

• Pseudomonas aeruginosa
• pulsed-field gel electrophoresis
• Egypt

Acknowledgements

The authors are grateful to Prof. Johen D. Klena, Head of Clinical Trials Programmes, and Prof. Salwa F. Ahmed, Deputy Head of Molecular Epidemiology Unit, CTMS Programmes AT naval Medical Research Unit No. 3 NAMRU # 3 Cairo, Egypt, for excellent training and assistance during PFGE analysis.