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In Vitro Assembly as a Tool to Investigate Catalytic Intermediates of [NiFe]-Hydrogenase.

ABSTRACT: [NiFe]-hydrogenases catalyze the reversible reaction H₂ ? 2H⁺ + 2e^-. Their basic module consists of a large subunit, coordinating the NiFe(CO)(CN)₂ center, and a small subunit that carries electron-transferring iron-sulfur clusters. Here, we report the in vitro assembly of fully functional [NiFe]-hydrogenase starting from the isolated large and small subunits. Activity assays complemented by spectroscopic measurements revealed a native-like hydrogenase. This approach was used to label exclusively the NiFe(CO)(CN)₂ center with ⁵⁷Fe, enabling a clear view of the catalytic site by means of nuclear resonance vibrational spectroscopy. This strategy paves the way for in-depth studies of [NiFe]-hydrogenase catalytic intermediates.

SUBMITTER: Caserta G

PROVIDER: S-EPMC7932190 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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In Vitro Assembly as a Tool to Investigate Catalytic Intermediates of [NiFe]-Hydrogenase.

Caserta Giorgio G Lorent Christian C Pelmenschikov Vladimir V Schoknecht Janna J Yoda Yoshitaka Y Hildebrandt Peter P Cramer Stephen P SP Zebger Ingo I Lenz Oliver O

ACS catalysis 20201116 23

[NiFe]-hydrogenases catalyze the reversible reaction H2 ⇄ 2H+ + 2e-. Their basic module consists of a large subunit, coordinating the NiFe(CO)(CN)2 center, and a small subunit that carries electron-transferring iron-sulfur clusters. Here, we report the in vitro assembly of fully functional [NiFe]-hydrogenase starting from the isolated large and small subunits. Activity assays complemented by spectroscopic measurements revealed a native-like hydr ...[more]

PMID: 33680535

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