Dictyostelium discoideum is an amoeba whose life cycle includes both single-cell and multicellular stages. The multicellular stage starts when individual amoebas of D. discoideum are starving. They then aggregate to form multicellular fruiting bodies holding amoeba spores.
D. discoideum hosts three species of bacterial symbionts in the genus Paraburkholderia (Brock, Noh et al, 2020). Around one quarter to one third of wild isolated D. discoideum are infected with these symbionts. Two of the species (P. bonniea and P. hayleyella) have evolved reduced genomes that are less than half the size of other Paraburkholderia. Their genomes show patterns that indicate adaptations to living in the host environment (Noh et al, 2022).
Our recent and ongoing research projects include (1) testing the fitness consequences of native and novel host-symbiont pairings (Noh et al, 2024); (2) comparing the genomes of amoeba-associated Paraburkholderia with other close relatives (Noh et al, 2022); and (3) investigating the functions and origins of candidate symbiosis genes we identified through comparative genomics.
We were featured in Colby Magazine online to celebrate our grant in 2020.
You can browse the Paraburkholderia symbiont genomes here.