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The Mitochondrion of Euglena gracilis
Verena Zimorski1, Cessa Rauch1, Jaap J van Hellemond2
1Institute of Molecular Evolution, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany.
Advances in Experimental Medicine and Biology
|April 22, 2017
Summary
Euglena gracilis mitochondria switch function under anaerobic conditions, producing wax esters from fatty acids. This unique process involves components found in both invertebrate mitochondria and protist hydrogenosomes.
Area of Science:
- Biochemistry
- Cell Biology
- Microbiology
Background:
- Euglena gracilis mitochondria exhibit mammalian-like function aerobically.
- Anaerobic metabolism in E. gracilis involves unique pathways distinct from aerobic respiration.
Purpose of the Study:
- To investigate the anaerobic energy metabolism of Euglena gracilis mitochondria.
- To identify the components and mechanisms of fatty acid synthesis and wax ester accumulation under anaerobiosis.
Main Methods:
- Comparative analysis of mitochondrial components.
- Biochemical assays to study fatty acid synthesis.
- Electron transport chain analysis under anaerobic conditions.
Main Results:
- Under anaerobiosis, E. gracilis mitochondria synthesize fatty acids independently of malonyl-CoA.
- Wax esters accumulate, serving as an electron sink for energy metabolism.
- Enzymes and cofactors involved show similarities to both invertebrate anaerobic mitochondria and protist hydrogenosomes.
Conclusions:
- Euglena gracilis possesses a unique anaerobic energy metabolism pathway.
- This pathway involves a malonyl-CoA independent fatty acid synthesis for wax ester production.
- The evolutionary origin of these components is mixed, drawing from different anaerobic energy-generating systems.
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