The endosymbiont of Epithemia clementina is specialized for nitrogen fixation within a photosynthetic eukaryote.

ABSTRACT: Epithemia spp. diatoms contain obligate, nitrogen-fixing endosymbionts, or "diazoplasts", derived from cyanobacteria. These algae are a rare example of photosynthetic eukaryotes that have successfully coupled oxygenic photosynthesis with oxygen-sensitive nitrogenase activity. Here, we report a newly-isolated species, E. clementina, as a model to investigate endosymbiotic acquisition of nitrogen fixation. To detect the metabolic changes associated with endosymbiotic specialization, we compared nitrogen fixation, associated carbon and nitrogen metabolism, and their regulatory pathways in the Epithemia diazoplast with its close, free-living cyanobacterial relative, Crocosphaera subtropica. Unlike C. subtropica, we show that nitrogenase activity in the diazop

SUBMITTER: Moulin SLY 

PROVIDER: S-EPMC10103950 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature