6HK5

X-ray structure of a truncated mutant of the metallochaperone CooJ with a high-affinity nickel-binding site

6HK5 の概要

• エントリーDOI: 10.2210/pdb6hk5/pdb
• 分子名称: CooJ, NICKEL (II) ION, DI(HYDROXYETHYL)ETHER, ... (8 entities in total)
• 機能のキーワード: metallochaperone, nickel-binding, metal binding protein
• 由来する生物種: Rhodospirillum rubrum
• タンパク質・核酸の鎖数: 8
• 化学式量合計: 62072.00

構造登録者

Alfano, M.,Perard, J.,Basset, C.,Carpentier, P.,Zambelli, B.,Timm, J.,Crouzy, S.,Ciurli, S.,Cavazza, C. (登録日: 2018-09-05, 公開日: 2019-03-27, 最終更新日: 2024-11-13)

主引用文献

Alfano, M.,Perard, J.,Carpentier, P.,Basset, C.,Zambelli, B.,Timm, J.,Crouzy, S.,Ciurli, S.,Cavazza, C.
The carbon monoxide dehydrogenase accessory protein CooJ is a histidine-rich multidomain dimer containing an unexpected Ni(II)-binding site.
J.Biol.Chem., 294:7601-7614, 2019

PubMed Abstract: Activation of nickel enzymes requires specific accessory proteins organized in multiprotein complexes controlling metal transfer to the active site. Histidine-rich clusters are generally present in at least one of the metallochaperones involved in nickel delivery. The maturation of carbon monoxide dehydrogenase in the proteobacterium requires three accessory proteins, CooC, CooT, and CooJ, dedicated to nickel insertion into the active site, a distorted [NiFeS] cluster coordinated to an iron site. Previously, CooJ from (CooJ) has been described as a nickel chaperone with 16 histidines and 2 cysteines at its C terminus. Here, the X-ray structure of a truncated version of CooJ, combined with small-angle X-ray scattering data and a modeling study of the full-length protein, revealed a homodimer comprising a coiled coil with two independent and highly flexible His tails. Using isothermal calorimetry, we characterized several metal-binding sites (four per dimer) involving the His-rich motifs and having similar metal affinity ( = 1.6 μm). Remarkably, biophysical approaches, site-directed mutagenesis, and X-ray crystallography uncovered an additional nickel-binding site at the dimer interface, which binds Ni(II) with an affinity of 380 nm Although CooJ was initially thought to be a unique protein, a proteome database search identified at least 46 bacterial CooJ homologs. These homologs all possess two spatially separated nickel-binding motifs: a variable C-terminal histidine tail and a strictly conserved H(W/F)HH motif, identified in this study, suggesting a dual function for CooJ both as a nickel chaperone and as a nickel storage protein.

PubMed: 30858174
DOI: 10.1074/jbc.RA119.008011

実験手法

X-RAY DIFFRACTION (2.042 Å)