A Solvent-Exposed Cysteine Forms a Peculiar NiII -Binding Site in the Metallochaperone CooT from Rhodospirillum rubrum.
Chemistry
; 25(67): 15351-15360, 2019 Dec 02.
Article
em En
| MEDLINE
| ID: mdl-31486181
ABSTRACT
In Rhodospirillum rubrum, the maturation of carbon monoxide dehydrogenase (CODH) requires three nickel chaperones, namely RrCooC, RrCooT and RrCooJ. Recently, the biophysical characterisation of the RrCooT homodimer and the X-ray structure of its apo form revealed the existence of a solvent-exposed NiII -binding site at the dimer interface, involving the strictly conserved Cys2. Here, a multifaceted approach that used NMR and X-ray absorption spectroscopies, complemented with structural bio-modelling methodologies, was used to characterise the binding mode of NiII in RrCooT. This study suggests that NiII adopts a square-planar geometry through a N2 S2 coordinating environment that comprises the two thiolate and amidate groups of both Cys2 residues at the dimer interface. The existence of a diamagnetic mononuclear NiII centre with bis-amidate/bis-thiolate ligands, coordinated by a single-cysteine motif, is unprecedented in biology and raises the question of its role in the activation of CODH at the molecular level.
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Texto completo:
1
Coleções:
01-internacional
Temas:
Geral
Base de dados:
MEDLINE
Assunto principal:
Rhodospirillum rubrum
/
Cisteína
/
Metalochaperonas
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Níquel
Idioma:
En
Revista:
Chemistry
Assunto da revista:
QUIMICA
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
França