Paraburkholderia symbionts isolated from Dictyostelium discoideum induce bacterial carriage in other Dictyostelium species

The social amoeba engages in a complex relationship with bacterial endosymbionts in the genus , which can benefit their host by imbuing it with the ability to carry prey bacteria throughout its life cycle. The relationship between and has been shown to take place across many strains and a large geographical area, but little is known about 's potential interaction with other dictyostelid species. We explore the ability of three species to stably infect and induce bacterial carriage in other dictyostelid hosts. We found that all three species successfully infected and induced carriage in seven species of hosts. While the overall behaviour was qualitatively similar to that previously observed in infections of , differences in the outcomes of different host/symbiont combinations suggest a degree of specialization between partners. was unable to maintain a stable association with the more distantly related host . Our results suggest that the mechanisms and evolutionary history of 's symbiotic relationships may be general within hosts, but not so general that it can associate with hosts of other genera. Our work further develops an emerging model system for the study of symbiosis in microbes.