Comparative analysis of KPC-2-encoding chimera plasmids with multi-replicon incR:Inc pa1763-kpc :IncN1 or incFII phn7a8 :Inc pa1763-kpc : IncN1

Abstract

Background: IncR, IncFII, Inc pA1763-KPC , and IncN1 plasmids have been increasingly found among Enterobacteriaceae species, but plasmids with hybrid structures derived from the above-mentioned incompatibility groups have not yet been described. Methods: Plasmids p721005-KPC, p504051-KPC, and pA3295-KPC were fully sequenced and compared with previously sequenced related plasmids pHN84KPC (IncR), pKPHS2 (IncFII K ), pKOX_NDM1 (IncFII Y ), pHN7A8 (IncFII pHN7A8 ), and R46 (IncN1). Results: The backbone of p721005-KPC/p504051-KPC was a hybrid of the entire 10-kb IncR-type backbone from pHN84KPC, the entire 64.3-kb IncFII K -type maintenance, and conjugal transfer regions from pKPHS2, a 15.5-kb IncFII Y -type maintenance region from pKOX_NDM1 and a 5.6-kb Inc pA1763-KPC -type backbone region from pA1763-KPC, and it contained a primary IncR replicon and two auxiliary Inc pA1763-KPC and IncN1 replicons. The backbone of pA3295-KPC was a hybrid of a 7.2-kb IncFII pHN7A8 -type backbone region from pHN7A8, the almost entire 33.3-kb IncN1-type maintenance and conjugal transfer regions highly similar to R46, a 26.2-kb IncFII K -type maintenance regions from pKPHS2, the above 15.5-kb IncFII Y -type maintenance region, and the above 5.6-kb Inc pA1763-KPC -type backbone region, and it contained a primary Inc-FII pHN7A8 replicon and two auxiliary Inc pA1763-KPC and IncN1 replicons. Each of p721005-KPC, p504051-KPC, and pA3295-KPC acquired a wealth of accessory modules, carrying a range of intact and residue mobile elements (such as insertion sequences, unit transposons, and integrons) and resistance markers (such as bla KPC , tetA, dfrA, and qnr). Conclusion: In each of p721005-KPC, p504051-KPC, and pA3295-KPC, multiple replicons in coordination with maintenance and conjugation regions of various origins would maintain a broad host range and a stable replication at a steady-state plasmid copy number.