2CA9

apo-NIKR from helicobacter pylori in closed trans-conformation

2CA9 の概要

• エントリーDOI: 10.2210/pdb2ca9/pdb
• 関連するPDBエントリー: 2CAD 2CAJ
• 分子名称: PUTATIVE NICKEL-RESPONSIVE REGULATOR, FORMIC ACID, GLYCEROL, ... (4 entities in total)
• 機能のキーワード: nickel uptake, transcription regulator, ribbon-helix-helix, acidic-adaptive response, transcriptional regulation, dna-binding, metal-binding, transcription
• 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: 34939.00

構造登録者

Dian, C.,Schauer, K.,Kapp, U.,McSweeney, S.M.,Labigne, A.,Terradot, L. (登録日: 2005-12-20, 公開日: 2006-07-17, 最終更新日: 2024-10-23)

主引用文献

Dian, C.,Schauer, K.,Kapp, U.,Mcsweeney, S.M.,Labigne, A.,Terradot, L.
Structural Basis of the Nickel Response in Helicobacter Pylori: Crystal Structures of Hpnikr in Apo and Nickel-Bound States.
J.Mol.Biol., 361:715-, 2006

PubMed Abstract: The survival of Helicobacter pylori in the human stomach critically relies on the availability and use of nickel, an absolute cofactor of the important virulence determinant urease. Nickel-responsive gene regulation is mediated by HpNikR, a protein belonging to the ribbon-helix-helix family of transcriptional regulators. Unlike its homologues, HpNikR acts as both a repressor and an activator within an acid adaptation cascade. We report the crystal structure of the full-length HpNikR in a nickel-free conformation and two nickel-bound structures obtained in different conditions: Ni1-HpNikR and Ni2-HpNikR. Apo-HpNikR shows the same global fold as its bacterial homologues although with an unusual closed trans-conformation and asymmetrical quaternary arrangement. The structure of Ni1-HpNikR in the presence of nickel has two different sides, one showing nickel binding similar to that of known NikRs and the other reflecting an intermediate state. The structure of Ni2-HpNikR obtained using a shorter exposure to nickel provides another snapshot of the nickel incorporation. Altogether, the three structures have allowed us to determine the route for nickel within HpNikR and reveal the cooperativity between the tetramerization domain and the DNA-binding domain. Experiments using point mutations of HpnikR residues involved in nickel internalisation confirm that these residues are critical for HpNikR functions in vivo.

PubMed: 16872629
DOI: 10.1016/J.JMB.2006.06.058

実験手法

X-RAY DIFFRACTION (2.05 Å)