2EFF

Crystal structure analysis of the complex between CyaY and Co(II)

Summary for 2EFF

• Entry DOI: 10.2210/pdb2eff/pdb
• Related: 1EW4 1SOY
• Descriptor: Protein cyaY, COBALT (II) ION (3 entities in total)
• Functional Keywords: frataxin, friedreich's ataxia iron binding, iron-sulfur cluster assembly, detoxifying redox-active iron, unknown function
• Biological source: Escherichia coli
• Total number of polymer chains: 1
• Total formula weight: 12360.22

Authors

Sica, F.,Franzese, M. (deposition date: 2007-02-22, release date: 2007-10-02, Last modification date: 2023-10-25)

Primary citation

Pastore, C.,Franzese, M.,Sica, F.,Temussi, P.,Pastore, A.
Understanding the binding properties of an unusual metal-binding protein - a study of bacterial frataxin
Febs J., 274:4199-4210, 2007

PubMed Abstract: Deficiency of the small mitochondrial protein frataxin causes Friedreich's ataxia, a severe neurodegenerative pathology. Frataxin, which has been highly conserved throughout evolution, is thought to be involved in, among other processes, Fe-S cluster formation. Independent evidence shows that it binds iron directly, although with very distinct features and low affinity. Here, we have carried out an extensive study of the binding properties of CyaY, the bacterial ortholog of frataxin, to different divalent and trivalent cations, using NMR and X-ray crystallography. We demonstrate that the protein has low cation specificity and contains multiple binding sites able to chelate divalent and trivalent metals with low affinity. Binding does not involve cavities or pockets, but exposed glutamates and aspartates, which are residues that are unusual for iron chelation when not assisted by histidines and/or cysteines. We have related how such an ability to bind cations on a relatively large area through an electrostatic mechanism could be a valuable asset for protein function.

PubMed: 17651435
DOI: 10.1111/j.1742-4658.2007.05946.x

Experimental method

X-RAY DIFFRACTION (1.8 Å)