Encyclopedia of Metalloproteins

2013 Edition
| Editors: Robert H. Kretsinger, Vladimir N. Uversky, Eugene A. Permyakov

Cytochrome c Oxidase, CuA Center

  • Peter M. H. Kroneck
  • Martha E. Sosa Torres
Reference work entry
DOI: https://doi.org/10.1007/978-1-4614-1533-6_93



CuA is a binuclear, mixed-valent [Cu(1.5+)-Cu(1.5+)], spin S = 1/2 electron transfer center present in respiratory chains of numerous organisms, specifically in cytochrome c oxidase (CcO) which reduces O2 to two molecules of H2O and nitrous oxide (N2O) reductase (N2OR) which reduces N2O to N2 and H2O. The core structure of CuA consists of a Cu2S2 rhomb with unique spectroscopic features, specifically the seven-line electron paramagnetic resonance spectrum observed at low temperatures.

Structure and Function of CuA


CcO (ferrocytochrome c:oxygen oxidoreductase; cytochrome aa 3; complex IV; EC is the key enzyme of cell respiration in all eukaryotes and many prokaryotes. In bacteria, CcO is located in the cell membrane, whereas in eukaryotic cells, the enzyme resides in the inner mitochondrial membrane (Wikström 2010; Yoshikawa et al. 2011). Mammalian and “classical” bacterial CcOs carry three...
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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Peter M. H. Kroneck
    • 1
  • Martha E. Sosa Torres
    • 2
  1. 1.Department of BiologyUniversity of KonstanzKonstanzGermany
  2. 2.Facultad de QuimicaUniversidad Nacional Autonoma de Mexico, Ciudad UniversitariaCoyoacan, Mexico DFMexico