Your browser version may not work well with NCBI's Web applications. More information here...
1: Inorg Chem. 2004 Dec 13;43(25):7897-901.
Related Articles, Links
Click here to read Click here to read
Site selection in tandem arrays of metal-binding domains.

Thickman KR, Davis A, Berg JM.

Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.

The metal binding properties of peptides corresponding to metal-binding sites spanning regions that normally function as linkers in tandem arrays of metal-binding domain-containing proteins were examined. For a peptide with two His residues from one TFIIIA-like zinc finger domain, a canonical TFIIIA-like linker, and two Cys residues from an adjacent zinc domain, the dissociation constant for the 1:1 peptide to cobalt(II) was found to be 15 +/- 10 microM, compared with 60 nM for the corresponding zinc finger domains themselves. Peptides overlapping two sets of metal-binding domains from human TRAF (tumor necrosis factor receptor-associated factor) proteins were examined. In one case, the affinity of the presumed metal-binding domain and that for the linker region were comparable, while in the second case, the affinity of the linker peptide was higher than that for the corresponding presumed metal-binding domain peptide. These studies revealed that cobalt(II) affinities in the micromolar range can occur even for peptides that do not correspond to natural zinc-binding domains and that the degree of distinction between authentic metal-binding domains and the corresponding linker-spanning peptides may be modest, at least for single domain peptide models.

PMID: 15578823 [PubMed - indexed for MEDLINE]