Fig. 6

Proposed model of the mobilization of the pLVPK-like nonconjugative virulence plasmid of K. pneumoniae. The initial step of virulence plasmid transfer is the acquisition of a conjugative IncF plasmid, and this step is followed by virulence plasmid mobilization via four modes. The virulence plasmid could be transferred (i) alone, (ii) cotransferred with the IncF plasmid, (iii) fused with the IncF plasmid due to recombination at specific 28-bp fusion sites or (iv) fused with the IncF plasmid due to recombination in the homologous region. The green rectangle denotes the tra gene cluster coding for a T4SS on the IncF plasmid. The orange triangles denote the specific 28-bp fusion site