2odx
From Proteopedia
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Solution structure of Zn(II)Cox4
Overview
Yeast Cox4 is a zinc binding subunit of cytochrome c oxidase. Cox4 is the, only cofactor-containing subunit that is not directly part of the, catalytic core of the enzyme located in the mitochondrial inner membrane., The Zn(II) site is shown to be distinct from the bovine ortholog, as it, results from the x-ray structure of the entire cytochrome c oxidase in, having a single histidyl residue and three conserved cysteines residues in, the coordination sphere. Substitutions at the Cys ligand positions result, in non-functional Cox4 proteins that fail to lead to cytochrome oxidase, assembly. Limited function exists in His-119 mutants when overexpressed., Zn(II) binding in Cox4 is, therefore, important for the stability of the, complex. The solution structure of yeast Cox4 elucidated by, multidimensional NMR reveals a C-terminal globular domain consisting of, two beta sheets analogous to the bovine ortholog except the loop, containing the coordinating His in the yeast protein and the fourth Cys in, the bovine protein are in different positions in the two structures. The, conformation of this loop is dictated by the different sequence position, of the fourth coordinating zinc ligand. The Zn(II) ion is buried within, the domain, consistent with its role in structural stability. Potential, functions of this matrix-facing subunit are discussed.
About this Structure
2ODX is a Single protein structure of sequence from Saccharomyces cerevisiae with ZN as ligand. Active as Cytochrome-c oxidase, with EC number 1.9.3.1 Full crystallographic information is available from OCA.
Reference
The characterization and role of zinc binding in yeast Cox4., Coyne HJ 3rd, Ciofi-Baffoni S, Banci L, Bertini I, Zhang L, George GN, Winge DR, J Biol Chem. 2007 Mar 23;282(12):8926-34. Epub 2007 Jan 10. PMID:17215247
Page seeded by OCA on Wed Nov 21 13:08:27 2007
