2HZV: Nikr-Operator Dna Complex

Metal ion homeostasis is critical to the survival of all cells. Regulation of nickel concentrations in Escherichia coli is mediated by the NikR repressor via nickel-induced transcriptional repression of the nickel ABC-type transporter, NikABCDE. Here, we report two crystal structures of nickel-activated E. coli NikR, the isolated repressor at 2.1 A resolution and in a complex with its operator DNA sequence from the nik promoter at 3.1 A resolution. Along with the previously published structure of apo-NikR, these structures allow us to evaluate functional proposals for how metal ions activate NikR, delineate the drastic conformational changes required for operator recognition, and describe the formation of a second metal-binding site in the presence of DNA. They also provide a rare set of structural views of a ligand-responsive transcription factor in the unbound, ligand-induced, and DNA-bound states, establishing a model system for the study of ligand-mediated effects on transcription factor function.
PDB ID: 2HZVDownload
MMDB ID: 106358
PDB Deposition Date: 2006/8/9
Updated in MMDB: 2013/01
Experimental Method:
x-ray diffraction
Resolution: 3.1  Å
Source Organism:
synthetic construct
Similar Structures:
Biological Unit for 2HZV: hexameric; determined by author
Molecular Components in 2HZV
Label Count Molecule
Proteins (4 molecules)
Nickel-responsive Regulator(Gene symbol: nikR)
Molecule annotation
Nucleotides(2 molecules)
5'- D(*ap*gp*tp*ap*tp*gp*ap*cp*gp*ap*ap*tp*ap*cp*tp*tp*ap*ap*ap *ap*tp*cp*gp*tp*cp*ap*tp*ap*cp*t)-3'
Molecule annotation
5'- D(*ap*gp*tp*ap*tp*gp*ap*cp*gp*ap*tp*tp*tp*tp*ap*ap*gp*tp*ap *tp*tp*cp*gp*tp*cp*ap*tp*ap*cp*t)-3'
Molecule annotation
Chemicals (9 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB