The CuA domain of Thermus thermophilus ba3-type cytochrome c oxidase at 1.6 A resolution.
Williams, P.A., Blackburn, N.J., Sanders, D., Bellamy, H., Stura, E.A., Fee, J.A., McRee, D.E.(1999) Nat Struct Biol 6: 509-516
- PubMed: 10360350 
- DOI: https://doi.org/10.1038/9274
- Primary Citation of Related Structures:  
2CUA - PubMed Abstract: 
The structure of the CuA-containing, extracellular domain of Thermus thermophilus ba3-type cytochrome c oxidase has been determined to 1.6 A resolution using multiple X-ray wavelength anomalous dispersion (MAD). The Cu2S2 cluster forms a planar rhombus with a copper-copper distance of 2.51 +/- 0.03 A. X-ray absorption fine-structure (EXAFS) studies show that this distance is unchanged by crystallization. The CuA center is asymmetrical; one copper is tetrahedrally coordinated to two bridging cysteine thiolates, one histidine nitrogen and one methionine sulfur, while the other is trigonally coordinated by the two cysteine thiolates and a histidine nitrogen. Combined sequence-structure alignment of amino acid sequences reveals conserved interactions between cytochrome c oxidase subunits I and II.
Organizational Affiliation: 
Department of Molecular Biology, The Scripps Research Institute, La Jolla, California 92037, USA.