Interplay of a non-conjugative integrative element and a conjugative plasmid in interspecies antibiotic resistance gene transfer.

(A) Two-step gene transfer model. First, the non-conjugative integrative element is transferred to a recipient cell via suicidal plasmid transfer and is then excised and integrated into the recipient chromosome. The subsequent plasmid transfer allows for integration of the plasmid backbone carrying antibiotic resistance genes into the recipient chromosome via homologous recombination using the homology of the integrative element. The diagram follows the canonical ICE excision model. (B) RecA-dependence of ARG transfer from V. ponticus to E. coli. The data were obtained from four independent mating assays. (C) Tn6283-dependence of ARG transfer from V. ponticus to E. coli. The data were obtained from five independent mating assays.