Trinuclear copper biocatalytic center forms an active site of thiocyanate dehydrogenase.
Proc Natl Acad Sci U S A
; 117(10): 5280-5290, 2020 03 10.
Article
em En
| MEDLINE
| ID: mdl-32094184
ABSTRACT
Biocatalytic copper centers are generally involved in the activation and reduction of dioxygen, with only few exceptions known. Here we report the discovery and characterization of a previously undescribed copper center that forms the active site of a copper-containing enzyme thiocyanate dehydrogenase (suggested EC 1.8.2.7) that was purified from the haloalkaliphilic sulfur-oxidizing bacterium of the genus Thioalkalivibrio ubiquitous in saline alkaline soda lakes. The copper cluster is formed by three copper ions located at the corners of a near-isosceles triangle and facilitates a direct thiocyanate conversion into cyanate, elemental sulfur, and two reducing equivalents without involvement of molecular oxygen. A molecular mechanism of catalysis is suggested based on high-resolution three-dimensional structures, electron paramagnetic resonance (EPR) spectroscopy, quantum mechanics/molecular mechanics (QM/MM) simulations, kinetic studies, and the results of site-directed mutagenesis.
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Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Oxirredutases
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Proteínas de Bactérias
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Bactérias Redutoras de Enxofre
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Cobre
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Domínio Catalítico
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Ectothiorhodospiraceae
Idioma:
En
Revista:
Proc Natl Acad Sci U S A
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Federação Russa