The cytochrome bc1 and cytochrome c oxidase complexes associate to form a single supracomplex in yeast mitochondria

J Biol Chem. 2000 Jun 16;275(24):18093-8. doi: 10.1074/jbc.M001901200.

Abstract

The mitochondrial electron transport chain complexes are large multisubunit complexes embedded in the inner membrane. We report here that in the yeast Saccharomyces cerevisiae, the cytochrome bc(1) and cytochrome c oxidase complexes co-exist as a larger complex of approximately 1000 kDa in the mitochondrial membrane. Following solubilization with a mild detergent, the cytochrome bc(1)-cytochrome c oxidase complex remains stable. It was analyzed using the techniques of gel filtration and blue native-polyacrylamide gel electrophoresis. Direct physical association of subunits of the cytochrome bc(1) complex with those of the cytochrome c oxidase complex was verified by co-immunoprecipitation analysis. Our data indicate that the cytochrome bc(1) complex is exclusively in association with the cytochrome c oxidase complex in yeast mitochondria. We term this complex the cytochrome bc(1)-cytochrome c oxidase supracomplex.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Electron Transport
  • Electron Transport Complex III / metabolism*
  • Electron Transport Complex IV / metabolism*
  • Electrophoresis, Polyacrylamide Gel
  • Intracellular Membranes / enzymology
  • Macromolecular Substances
  • Mitochondria / enzymology*
  • Molecular Weight
  • Protein Conformation
  • Yeasts

Substances

  • Macromolecular Substances
  • Electron Transport Complex IV
  • Electron Transport Complex III