Complete Sequencing of IncI1 Sequence Type 2 Plasmid pJIE512b Indicates Mobilization of bla_CMY-2 from an IncA/C Plasmid

Different bla_CMY-2 contexts. ISEcp1 is indicated by dark blue, inverted repeats are indicated by vertical black bars, and direct repeats are labeled and indicated by vertical gray bars. IS1294 and IS1294-like elements are depicted with green and stippled green, respectively, target sites are labeled with black arrows, terIS sequences are depicted with green dots, and terIS look-alike sequences are depicted with black dots. Plasmid backbones are indicated by dashed red (IncA/C), cyan (IncI1), and pink (IncFII) lines. IncA/C backbone regions that have been mobilized are indicated by solid red lines. The lengths of the Citrobacter freundii part of the insertions are shown. (a) C. freundii chromosomal region, including bla_CMY-2 (GenBank accession no. U21727 and AY125469). (b) The 2,823-bp bla_CMY-2 region in IncA/C plasmid pAR060302 (GenBank accession no. FJ621588) is associated with a complete ISEcp1, and the whole insert is flanked by direct repeats. IS1294 is present elsewhere in the backbone. (c) bla_CMY-2 context in pJIE512b. The insert is flanked by the IS1294 target site CTTG at the 5′ end and bounded by the IS1294 terIS look-alike sequence GTTC at the 3′ end. (d) IncA/C plasmid pSH696_135 (GenBank accession no. JN983048) contains a complex ISEcp1-bla_CMY-2 arrangement, part of which is shown. An IS1294b element is present elsewhere in the plasmid. (e) The IS1294b-ΔISEcp1-bla_CMY-2 segment in pR7AC (GenBank accession no. KF434766) and pTN38148 (FM246883) is flanked at the 5′ end by the imperfect target site GTCC and bounded at the 3′ end by the terIS look-alike sequence GTTC. (f) The shorter bla_CMY-2 insert in the IncFII plasmid pEQ011 (GenBank accession no. KF582523) is flanked by the IS1294 target site GTTC and the imperfect terIS look-alike sequence CTTG.