They took our genes [rutgers.edu]:
About 100 million years ago, a lowly amoeba pulled off a stunning heist, grabbing genes from an unsuspecting bacterium to replace those it had lost. Now Rutgers and other scientists have solved the mystery of how the little amoeba, Paulinella, committed the theft. It engulfed the bacterium, kept that cell alive and harnessed its genes for photosynthesis, the process plants and algae use to convert carbon dioxide into oxygen and sugar via solar energy.
"The major finding of the study is the microbial world, which we know is full of valuable genes, can move these genes between organisms according to need," said Debashish Bhattacharya [rutgers.edu], a study co-author and distinguished professor in the Department of Ecology, Evolution and Natural Resources [rutgers.edu] at Rutgers. "When a microbe has a gene deficit, it can in some cases fill that deficit by grabbing the same gene from the environment. This shows how fluid microbial genomes really are."
Gene transfers from diverse bacteria compensate for reductive genome evolution in the chromatophore of Paulinella chromatophora [pnas.org] (DOI: 10.1073/pnas.1608016113) (DX [doi.org])