Analysis of Integrons and Associated Gene Cassettes in Clinical Isolates of Escherichia coli

Background and Objective: Horizontal transfer of integrons is the most successful transfer of antimicrobial resistance genes and the emergence of multi-drug resistance strains. The aim of the present study was to investigate the prevalence of class I and II integrons and their gene cassette assortments and antibiotic resistance profile in Escherichia coli strains isolated from diarrheal and urine specimens. Materials and Methods: In this cross-sectional study 200 E. coli isolates were collected from the clinical urine and stool specimens. After identification of isolates by biochemical tests, the antibiotic susceptibility test (disk diffusion method) was done according to CLSI advice against 13 antibiotics. DNA extraction was performed and class 1 and 2 integrons and associated gene cassettes were determined using PCR method. Results: The highest resistance was found against erythromycin (96.5%) and %98.5 of isolates were susceptible to imipenem. 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Analysis of Integrons and Associated Gene Cassettes in Clinical Isolates of Escherichia coli Keywords:

Keywords: Escherichia coli , Integron , Gene cassette , Antibiotic resistance