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Updated: Jun 25, 2026
09:50
Preparation and Reactivity of Gasless Nanostructured Energetic Materials
Published on: April 2, 2015
An anaerobic mitochondrion that produces hydrogen
Brigitte Boxma1, Rob M de Graaf, Georg W M van der Staay
1Department of Evolutionary Microbiology, Faculty of Science, Radboud University Nijmegen, Toernooiveld 1, NL-6525 ED Nijmegen, The Netherlands.
Nature
|March 4, 2005
Summary
The study identifies the Nyctotherus ovalis hydrogenosome as a crucial evolutionary link. This organelle retains a genome and mitochondrial features, bridging the gap between mitochondria and hydrogenosomes.
Area of Science:
- Cell Biology
- Evolutionary Biology
- Microbiology
Background:
- Hydrogenosomes are organelles producing ATP and hydrogen in diverse eukaryotes.
- Significant structural and metabolic differences exist among hydrogenosomes, fueling debate on their evolutionary origins.
- Mitochondria also exhibit considerable diversity.
Purpose of the Study:
- To investigate the evolutionary origin of hydrogenosomes.
- To characterize the hydrogenosomes of the anaerobic ciliate Nyctotherus ovalis.
- To determine if N. ovalis hydrogenosomes represent a transitional form between mitochondria and hydrogenosomes.
Main Methods:
- Phylogenetic analysis of organelle genomes.
- Identification of nucleus-encoded mitochondrial proteins.
- Biochemical assays using mitochondrial inhibitors.
- Metabolic end product analysis.
Main Results:
- N. ovalis hydrogenosomes possess a rudimentary genome encoding mitochondrial electron transport chain components.
- Phylogenetic analyses show these proteins are homologous to those in aerobic ciliates.
- The organelle is sensitive to mitochondrial complex I inhibitors and produces succinate, characteristic of anaerobic mitochondria.
Conclusions:
- The N. ovalis hydrogenosome contains a genome and exhibits biochemical traits linking it to anaerobic mitochondria.
- This organelle serves as a key evolutionary intermediate between mitochondria and hydrogenosomes.
- Understanding this link provides insights into organelle evolution in eukaryotes.
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