Fig. 7.
—Possible roles of Providencia rettgeri in blaNDM-1-plasmids evolution in Latin America. In an initial stage pNDM-BJ01-like plasmids are acquired from Acinetobacter spp. (−1). Shortly after, blaNDM-1 is transposed to pPrY-like plasmids (from P. rettgeri circulation; −2) or IncA/C2 plasmids (from Klebsiella pneumoniae, Escherichia coli or other Enterobacteriaceae; −3) via Tn125 transposition or by mean of other mobile genetic elements surrounding the Tn125 (or its remnants). IncA/C2 blaNDM-1-plasmids could be transferred to a broad bacteria host range (−4). It is also possible that a non-Providencia Enterobacteriaceae could capture a pNDM-BJ01-like plasmid and transposes Tn125 to a broad host range IncA/C2 plasmid (−5); later this IncA/C2 blaNDM-1-plasmid could be conjugated to P. rettgeri (−6). An interesting finding of the present study is the generation in P. rettgeri of new plasmids by mean of co-integration of pPrY-like plasmids and IncA/C2 plasmids (−7). These chimeric structures can also be transposed to the P. rettgeri chromosome (−8). The Tn125 (or its remnants) could be transposed to new plasmid backbones with possible implications upon its dissemination (−9). Additionally, by mean of partial conjugation could be disseminated IncA/C2-related (repA negative) blaNDM-1-plasmids (−10).