Diverse <i>dif</i> module content and configurations in the r3-T5 group of Rep_3/OrfX plasmids from <i>Acinetobacter</i> species reveal extensive <i>dif</i> module shuffling

The plasmids that are associated with <i>Acinetobacter</i> isolates appear to be restricted to this genus. However, the unique properties of the many and various plasmid types found in <i>Acinetobacter</i> species have received little attention relative to the plasmids of other gram-negative pathogens. In addition, the novel <i>dif</i> module mobile element system, also found uniquely in <i>Acinetobacter</i> species, was recently shown to be naturally associated with a specific type of <i>Acinetobacter</i> plasmid. To investigate the dynamics of <i>dif</i> module movement, here, the properties and configurations of one group of plasmids with identical or closely related backbones that carry different <i>dif</i> modules or the same modules in different configurations have been examined. This will increase understanding of the global distribution and diversity of plasmids that carry <i>dif</i> modules, as well as provide insight into the way <i>dif</i> modules relocate.