Divergent mitochondrial respiratory chains in phototrophic relatives of apicomplexan parasites

Flegontov, P. et al. (2015) Divergent mitochondrial respiratory chains in phototrophic relatives of apicomplexan parasites. Molecular Biology and Evolution, 32(5), pp. 1115-1131. (doi: 10.1093/molbev/msv021) (PMID:25660376)

Abstract

Four respiratory complexes and ATP-synthase represent central functional units in mitochondria. In some mitochondria and derived anaerobic organelles, a few or all of these respiratory complexes have been lost during evolution. We show that the respiratory chain of Chromera velia, a phototrophic relative of parasitic apicomplexans, lacks complexes I and III, making it a uniquely reduced aerobic mitochondrion. In Chromera, putative lactate:cytochrome c oxidoreductases are predicted to transfer electrons from lactate to cytochrome c, rendering complex III unnecessary. The mitochondrial genome of Chromera has the smallest known protein-coding capacity of all mitochondria, encoding just cox1 and cox3 on heterogeneous linear molecules. In contrast, another photosynthetic relative of apicomplexans, Vitrella brassicaformis, retains the same set of genes as apicomplexans and dinoflagellates (cox1, cox3, and cob).

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Otto, Professor Thomas
• Authors: Flegontov, P., Michálek, J., Janouškovec, J., Lai, D.-H., Jirků, M., Hajdušková, E., Tomčala, A., Otto, T. D., Keeling, P. J., Pain, A., Oborník, M., and Lukeš, J.
• College/School: College of Medical Veterinary and Life Sciences > School of Infection & Immunity
• Journal Name: Molecular Biology and Evolution
• Publisher: Oxford University Press
• ISSN: 0737-4038
• ISSN (Online): 1537-1719
• Published Online: 06 February 2015