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Hydride state accumulation in native [FeFe]-hydrogenase with the physiological reductant H₂ supports its catalytic relevance.

ABSTRACT: Small molecules in solution may interfere with mechanistic investigations, as they can affect the stability of catalytic states and produce off-cycle states that can be mistaken for catalytically relevant species. Here we show that the hydride state (H_hyd), a proposed central intermediate in the catalytic cycle of [FeFe]-hydrogenase, can be formed in wild-type [FeFe]-hydrogenases treated with H₂ in absence of other, non-biological, reductants. Moreover, we reveal a new state with unclear role in catalysis induced by common low pH buffers.

SUBMITTER: Senger M

PROVIDER: S-EPMC9219605 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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Hydride state accumulation in native [FeFe]-hydrogenase with the physiological reductant H2 supports its catalytic relevance.

Senger Moritz M Kernmayr Tobias T Lorenzi Marco M Redman Holly J HJ Berggren Gustav G

Chemical communications (Cambridge, England) 20220623 51

Small molecules in solution may interfere with mechanistic investigations, as they can affect the stability of catalytic states and produce off-cycle states that can be mistaken for catalytically relevant species. Here we show that the hydride state (Hhyd), a proposed central intermediate in the catalytic cycle of [FeFe]-hydrogenase, can be formed in wild-type [FeFe]-hydrogenases treated with H2 in absence of other, non-biological, reductants. Moreover, we reveal a new stat ...[more]

PMID: 35670542

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