Differential remodelling of peroxisome function underpins the environmental and metabolic adaptability of diplonemids and kinetoplastids

摘要

The remodelling of organelle function is increasingly appreciated as a central driver of eukaryotic biodiversity and evolution. Kinetoplastids including Trypanosoma and Leishmania have evolved specialised peroxisomes, called glycosomes. Glycosomes uniquely contain a glycolytic pathway as well as other enzymes, which underpin the physiological flexibility of these major humanpathogens. The sister group of kinetoplastids are the diplonemids, which are among the most abundant eukaryotes in marine plankton. Here we demonstrate the compartmentalisation of gluconeogenesis, or glycolysis in reverse, in the peroxisomes of the free-living marine diplonemid, Diplonema papillatum. Our results suggest that peroxisome modification was already underway in the common ancestor of kinetoplastids and diplonemids, and raise the possibility that the central importance of gluconeogenesis to carbon metabolism in theheterotrophic free-living ancestor may have been an important selective driver. Our data indicate that peroxisome modification is not confined to the kinetoplastid lineage, but has also been a factor in the success of their free-living euglenozoan relatives.