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A [RuRu] Analogue of an [FeFe]-Hydrogenase Traps the Key Hydride Intermediate of the Catalytic Cycle.

ABSTRACT: The active site of the [FeFe]-hydrogenases features a binuclear [2Fe]H sub-cluster that contains a unique bridging amine moiety close to an exposed iron center. Heterolytic splitting of H2 results in the formation of a transient terminal hydride at this iron site, which, however is difficult to stabilize. We show that the hydride intermediate forms immediately when [2Fe]H is replaced with [2Ru]H analogues through artificial maturation. Outside the protein, the [2Ru]H analogues form bridging hydrides, which rearrange to terminal hydrides after insertion into the apo-protein. H/D exchange of the hydride only occurs for [2Ru]H analogues containing the bridging amine moiety.

SUBMITTER: Sommer C

PROVIDER: S-EPMC5924579 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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A [RuRu] Analogue of an [FeFe]-Hydrogenase Traps the Key Hydride Intermediate of the Catalytic Cycle.

Sommer Constanze C Richers Casseday P CP Lubitz Wolfgang W Rauchfuss Thomas B TB Reijerse Edward J EJ

Angewandte Chemie (International ed. in English) 20180326 19

The active site of the [FeFe]-hydrogenases features a binuclear [2Fe]H sub-cluster that contains a unique bridging amine moiety close to an exposed iron center. Heterolytic splitting of H2 results in the formation of a transient terminal hydride at this iron site, which, however is difficult to stabilize. We show that the hydride intermediate forms immediately when [2Fe]H is replaced with [2Ru]H analogues through artificial maturation. Outside the prot ...[more]

PMID: 29577535

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