Plasmids are important drivers of bacterial evolution, but it is challenging to understand how plasmids persist over the long term because plasmid carriage is costly. Classical models predict that horizontal transfer is necessary for plasmid persistence, but recent work shows that almost half of plasmids are non-transmissible. Here we use a combination of… (More)
Plasmids play a key role in bacterial evolution by providing bacteria with new and important functions, such as antibiotic resistance. New research shows how bacterial regulatory evolution can stabilize bacteria-plasmid associations and catalyze evolutionary innovation.