1. Integron structure and gene capture mechanism.
Integron structure and gene capture mechanism. This figure indicates the basic elements of integrons, as found in bacterial genomes. The structure consists of an integrase (Int) with the Pint and PC promoters in the 3′ end of the gene, with its associated cassette attachment or insertion site (attI). The integrase catalyzes the sequential recombination of circularized gene cassettes into the distal attachment site to create an operon-like arrangement (ant1r, ant2r, and so on) of r genes transcribed from the strong PC promoter (132). Three classes of integrons have been identified that differ in their integrase genes.
Julian Davies, and Dorothy Davies Microbiol. Mol. Biol. Rev. 2010; doi: /MMBR