Download MendeleyCrystal Structure of the Nickel-Responsive Transcription Factor NikR
Schreiter, E.R., Sintchak, M.D., Guo, Y., Chivers, P.T., Sauer, R.T., Drennan, C.L.(2003) Nat Struct Biol 10: 794-799
- PubMed: 12970756
- DOI: https://doi.org/10.1038/nsb985
- Primary Citation of Related Structures:
1Q5V, 1Q5Y - PubMed Abstract:
NikR is a metal-responsive transcription factor that controls nickel uptake in Escherichia coli by regulating expression of a nickel-specific ATP-binding cassette (ABC) transporter. We have determined the first two structures of NikR: the full-length apo repressor at a resolution of 2.3 A and the nickel-bound C-terminal regulatory domain at a resolution of 1.4 A. NikR is the only known metal-responsive member of the ribbon-helix-helix family of transcription factors, and its structure has a quaternary arrangement consisting of two dimeric DNA-binding domains separated by a tetrameric regulatory domain that binds nickel. The position of the C-terminal regulatory domain enforces a large spacing between the contacts that each NikR DNA-binding domain can make with the nik operator. The regulatory domain of NikR contains four nickel-binding sites at the tetramer interface, each exhibiting a novel square-planar coordination by three histidines and one cysteine side chain.
Organizational Affiliation:
Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts, 02139 USA.
