A
hydrogenosome is a membrane-enclosed
organelle of some
anaerobic ciliates,
trichomonads,
fungi, and
animals. The hydrogenosomes of trichomonads (the most studied of the hydrogenosome-containing microorganisms) produce molecular
hydrogen,
acetate,
carbon dioxide and
ATP by the combined actions of
pyruvate:ferredoxin oxido-reductase,
hydrogenase,
acetate:succinate CoA transferase and
succinate thiokinase.
Superoxide dismutase,
malate dehydrogenase (decarboxylating),
ferredoxin,
adenylate kinase and
NADH:ferredoxin oxido-reductase are also localized in the hydrogenosome. It is nearly universally accepted that hydrogenosomes evolved from
mitochondria.
