Gene cassettes: a new class of mobile element

Mobile gene cassettes: a fundamental resource for bacterial evolution.

Horizontal gene transfer increases genetic diversity in prokaryotes to a degree not allowed by the limitations of reproduction by binary fission. The integron/gene cassette system is one of the most recently characterized examples of a system that facilitates horizontal gene transfer. This system, discovered in the context of multidrug resistance, is recognized in a clinical context for its rol...

Detection of gene cassettes in Tn402-like class 1 integrons.

Amplification of the gene cassettes in class 1 integrons by PCR using primers in the 5 conserved segment (5 -CS) and the 3 -CS (7, 8) has been used in hundreds of studies to identify integron-associated resistance genes (Fig. 1A). Equivalent PCR primers that detect cassettes in class 2 integrons, i.e., Tn7 family transposons (18), are also widely used. The approach used to detect integrons in a...

Gene cassettes and cassette arrays in mobile resistance integrons.

Gene cassettes are small mobile elements, consisting of little more than a single gene and recombination site, which are captured by larger elements called integrons. Several cassettes may be inserted into the same integron forming a tandem array. The discovery of integrons in the chromosome of many species has led to the identification of thousands of gene cassettes, mostly of unknown function...

Characterisation of two new gene cassettes, aadA5 and dfrA17.

Escherichia coli INS33 was isolated from the urinary tract of an infected patient. It was resistant to ampicillin, chloramphenicol, spectinomycin, streptomycin, sulfafurazole, tetracycline and trimethoprim. PCR screening revealed the presence of a class 1 integron that harboured two new gene cassettes, designated dfrA17 and aadA5. The new dfrA17 cassette was 91% identical to the known dfrA7 cas...

A New Class of Banach Sequence Spaces