Figure 2. Genetic organization of the strA-strB genes. Schematic representation of the regions of Tn5393 and derivatives and of plasmids RSF1010, and pIP1203 carrying the strA and strB genes. IR, inverted repeat; tnpA, transposase; res, resolution site; tnpR, resolvase; IS1133 and IS6100, insertion sequences; korB and incC, genes homologous to those involved in regulation and partition of plasmid R751, respectively; oriV, origin of vegetative replication of R751. Direction of gene transcription is indicated by arrows.