2KM0

Cu(I)-bound CopK

2KM0 の概要

• エントリーDOI: 10.2210/pdb2km0/pdb
• 関連するPDBエントリー: 2K0Q
• NMR情報: BMRB: 16408
• 分子名称: Copper resistance protein K, COPPER (I) ION (2 entities in total)
• 機能のキーワード: heavy metal resistance, periplasmic copper binding protein, copper, periplasm, plasmid, metal binding protein
• 由来する生物種: Ralstonia metallidurans
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 8358.11

構造登録者

Bersch, B. (登録日: 2009-07-15, 公開日: 2010-03-16, 最終更新日: 2024-05-01)

主引用文献

Sarret, G.,Favier, A.,Hazemann, J.L.,Mergeay, M.,Bersch, B.
CopK from Cupriavidus metallidurans CH34 Binds Cu(I) in a Tetrathioether Site: Characterization by X-ray Absorption and NMR Spectroscopy
J.Am.Chem.Soc., 2010

PubMed Abstract: Cupriavidus metallidurans CH34 is a bacterium that is resistant to high metal concentrations in the environment. Increased copper resistance is associated with the cop cluster on the large plasmid pMOL30 that is composed of at least 21 genes. The copK gene encodes a 74 residue periplasmic protein whose expression is strongly upregulated in the presence of copper. CopK was previously shown to cooperatively bind Cu(I) and Cu(II) in distinct, specific sites. The solution structure of Cu(I)-CopK and the characterization of the Cu(I) site by X-ray absorption spectroscopy and NMR are reported here. EXAFS spectra are in agreement with a tetrathioether Cu(I) site, providing so far unique spectral information on a 4S-coordinated Cu(I) in a protein. The methionine residues forming the Cu(I) site, M28, M38, M44, and M54, are identified by NMR. We propose the chemical shift of the methionine C(epsilon) as a new and sensitive probe for the detection of Cu(I) bound to thioether groups. The solution structure of Cu(I)-CopK demonstrates that Cu(I) binding induces a complete structural modification with the disruption of the second beta-sheet and a rotation of the C-terminal part of nearly 180 degrees around a hinge formed by asparagine 57. This conformational change is directly related to the loss of the dimer interface and most probably to the formation of the Cu(II) site involving histidine 70. The solution structure of Cu(I)-CopK therefore provides the molecular basis for the understanding of the Cu(I)/Cu(II) binding cooperativity.

PubMed: 20192263
DOI: 10.1021/ja9083896

実験手法

SOLUTION NMR