2hzv
From Proteopedia
NikR-operator DNA complex
Overview
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.
About this Structure
2HZV is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
NikR-operator complex structure and the mechanism of repressor activation by metal ions., Schreiter ER, Wang SC, Zamble DB, Drennan CL, Proc Natl Acad Sci U S A. 2006 Sep 12;103(37):13676-81. Epub 2006 Aug 31. PMID:16945905 Page seeded by OCA on Sun May 4 06:54:43 2008
