2WVF

Structural and mechanistic insights into Helicobacter pylori NikR function

2WVF の概要

• エントリーDOI: 10.2210/pdb2wvf/pdb
• 関連するPDBエントリー: 2CA9 2CAD 2CAJ 2WVB 2WVC 2WVD 2WVE
• 分子名称: PUTATIVE NICKEL-RESPONSIVE REGULATOR, NICKEL (II) ION, GLYCEROL, ... (6 entities in total)
• 機能のキーワード: transcription factor, transcription regulation, rhh, nikr, dna-binding, transcription, metal-binding, metalloregulator
• 由来する生物種: HELICOBACTER PYLORI
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 35016.22

構造登録者

Dian, C.,Bahlawane, C.,Muller, C.,Round, A.,Delay, C.,Fauquant, C.,Schauer, K.,de Reuse, H.,Michaud-Soret, I.,Terradot, L. (登録日: 2009-10-16, 公開日: 2010-01-19, 最終更新日: 2023-12-20)

主引用文献

Bahlawane, C.,Dian, C.,Muller, C.,Round, A.,Fauquant, C.,Schauer, K.,De Reuse, H.,Terradot, L.,Michaud-Soret, I.
Structural and Mechanistic Insights Into Helicobacter Pylori Nikr Activation.
Nucleic Acids Res., 38:3106-, 2010

PubMed Abstract: NikR is a transcriptional metalloregulator central in the mandatory response to acidity of Helicobacter pylori that controls the expression of numerous genes by binding to specific promoter regions. NikR/DNA interactions were proposed to rely on protein activation by Ni(II) binding to high-affinity (HA) and possibly secondary external (X) sites. We describe a biochemical characterization of HpNikR mutants that shows that the HA sites are essential but not sufficient for DNA binding, while the secondary external (X) sites and residues from the HpNikR dimer-dimer interface are important for DNA binding. We show that a second metal is necessary for HpNikR/DNA binding, but only to some promoters. Small-angle X-ray scattering shows that HpNikR adopts a defined conformation in solution, resembling the cis-conformation and suggests that nickel does not trigger large conformational changes in HpNikR. The crystal structures of selected mutants identify the effects of each mutation on HpNikR structure. This study unravels key structural features from which we derive a model for HpNikR activation where: (i) HA sites and an hydrogen bond network are required for DNA binding and (ii) metallation of a unique secondary external site (X) modulates HpNikR DNA binding to low-affinity promoters by disruption of a salt bridge.

PubMed: 20089510
DOI: 10.1093/NAR/GKP1216

実験手法

X-RAY DIFFRACTION (1.6 Å)