Two large conjugative resistance (R) plasmids from clinical strains of Salmonella enterica serovar Virchow carried a class 2 integron with the 5' conserved sequence (5'CS)-dfrA1-sat1-aadA1-3'CS gene array, which is associated with defective Tn7 transposons. In addition, each contained a different class 1 integron (with 5'CS-aadA1-3'CS or 5'CS-sat-smr-aadA1-3'CS gene arrays) linked to Tn21-Tn9 s...

The integron is a genetic element that incorporates mobile genes termed gene cassettes into a reserved genetic site via site-specific recombination. It is best known for its role in antibiotic resistance with one type of integron, the class 1 integron, a major player in the dissemination of antibiotic resistance genes across Gram negative pathogens and commensals. However, integrons are ancient...

background and objectives: klebsiella species are of the most common bacteria involved in nosocomial and urinary tract infections. genetic elements such as class 1 integrons have an important role in the resistance development. in this study, the share of class 1 integrons, the genetic characterization of the integron cassettes and pfge profiles of the clinical klebsiella isolates are evaluated...

Class 1 integrons have played a major role in the global dissemination of antibiotic resistance. Reconstructing the history of class 1 integrons might help us control further spread of antibiotic resistance by understanding how human activities influence microbial evolution. Here we describe a class 1 integron that represents an intermediate stage in the evolutionary history of clinical integro...

OBJECTIVES To analyse the gene cassettes and determine the roles of class 1 and class 2 integrons in antibiotic-resistant strains of Shigella sonnei (n=31) and Shigella flexneri (n=33). METHODS Various molecular techniques, including PCR and Southern-blotting analysis, were used to analyse various markers of class 1 and class 2 integrons in these 64 S. sonnei and S. flexneri isolates collecte...

The spread of orf513-bearing class 1 integrons is associated with bla(CTX-M-2) in gram-negative clinical isolates in Argentina, with In35 being the most frequently found integron (74%). Among 65 isolates without bla(CTX-M-2), only one harbored a novel orf513-bearing class 1 integron with the dfrA3b gene. The finding of orf513 not associated with class 1 integrons in two gram-positive strains in...

background: infectious by pseudomonas aeruginosa has spread worldwide and metallo-beta-lactamases (mbl) are being reported with increasing frequency. the aim of this study was to investigate the antibiotic susceptibility and distribution of blavim and blaimp genes in p. aeruginosa isolates from zanjan province of iran. methods: a total of 70 p. aeruginosa isolates were identified from patients ...

background: extended spectrum beta lactamases (esbls) are an important cause of transferable multidrug resistance (mdr) in gram-negative bacteria. the most described esbl genes are generally found within integron-like structures as mobile genetic elements. the aim of this study was to identify the accompanying of class 1 integrons and esbls in the mdr e. coli isolates. methods: susceptibility t...