3ZJA

The crystal structure of a Cu(I) metallochaperone from Streptomyces lividans

3ZJA の概要

• エントリーDOI: 10.2210/pdb3zja/pdb
• 分子名称: SL3965, COPPER (II) ION (3 entities in total)
• 機能のキーワード: chaperone
• 由来する生物種: STREPTOMYCES LIVIDANS
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 14730.65

構造登録者

Blundell, K.L.I.M.,Hough, M.,Worrall, J.A.R. (登録日: 2013-01-17, 公開日: 2014-01-29, 最終更新日: 2024-05-08)

主引用文献

Blundell, K.L.I.M.,Hough, M.A.,Vijgenboom, E.,Worrall, J.A.R.
Structural and Mechanistic Insights Into an Extracytoplasmic Copper Trafficking Pathway in Streptomyces Lividans.
Biochem.J., 459:525-, 2014

PubMed Abstract: In Streptomyces lividans an extracytoplasmic copper-binding Sco protein plays a role in two unlinked processes: (i) initiating a morphological development switch and (ii) facilitating the co-factoring of the CuA domain of CcO (cytochrome c oxidase). How Sco obtains copper once secreted to the extracytoplasmic environment is unknown. In the present paper we report on a protein possessing an HX₆MX₂₁HXM motif that binds a single cuprous ion with subfemtomolar affinity. High-resolution X-ray structures of this extracytoplasmic copper chaperone-like protein (ECuC) in the apo- and Cu(I)-bound states reveal that the latter possesses a surface-accessible cuprous-ion-binding site located in a dish-shaped region of β-sheet structure. A cuprous ion is transferred under a favourable thermodynamic gradient from ECuC to Sco with no back transfer occurring. The ionization properties of the cysteine residues in the Cys⁸⁶xxxCys⁹⁰ copper-binding motif of Sco, together with their positional locations identified from an X-ray structure of Sco, suggests a role for Cys⁸⁶ in initiating an inter-complex ligand-exchange reaction with Cu(I)-ECuC. Generation of the genetic knockouts, Δsco, Δecuc and Δsco/ecuc, and subsequent in vivo assays lend support to the existence of a branched extracytoplasmic copper-trafficking pathway in S. lividans. One branch requires both Sco and to a certain extent ECuC to cofactor the CuA domain, whereas the other uses only Sco to deliver copper to a cuproenzyme to initiate morphological development.

PubMed: 24548299
DOI: 10.1042/BJ20140017

実験手法

X-RAY DIFFRACTION (1.48 Å)