Plasmid Characteristics Modulate the Propensity of Gene Exchange in Bacterial Vesicles

Extracellular vesicle formation and exchange are common within bacterial populations. Vesicles package multiple types of biomolecules, including genetic material. The exchange of extracellular vesicles containing genetic material facilitates interspecies DNA transfer and may be a promiscuous mechanism of horizontal gene transfer. Unlike other mechanisms of horizontal gene transfer, it is unclear whether characteristics of the exchanged DNA impact the likelihood of transfer in vesicles. Here, we systematically examine the influence of plasmid copy number, size, and origin of replication on the loading of DNA into vesicles and the uptake of DNA containing vesicles by recipient cells. These results reveal how each plasmid characteristic impacts gene transfer in vesicles and contribute to a greater understanding of the importance of vesicle-mediated gene exchange in the landscape of horizontal gene transfer.