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Electrocatalytic mechanism of reversible hydrogen cycling by enzymes and distinctions between the major classes of hydrogenases.

ABSTRACT: The extraordinary ability of Fe- and Ni-containing enzymes to catalyze rapid and efficient H(+)/H(2) interconversion--a property otherwise exclusive to platinum metals--has been investigated in a series of experiments combining variable-temperature protein film voltammetry with mathematical modeling. The results highlight important differences between the catalytic performance of [FeFe]-hydrogenases and [NiFe]-hydrogenases and justify a simple model for reversible catalytic electron flow in enzymes and electrocatalysts that should be widely applicable in fields as diverse as electrochemistry, catalysis, and bioenergetics. The active site of [FeFe]-hydrogenases, an intricate Fe-carbonyl complex known as the "H cluster," emerges as a supreme catalyst.

SUBMITTER: Hexter SV

PROVIDER: S-EPMC3406873 | biostudies-other | 2012 Jul

REPOSITORIES: biostudies-other

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Electrocatalytic mechanism of reversible hydrogen cycling by enzymes and distinctions between the major classes of hydrogenases.

Hexter Suzannah V SV Grey Felix F Happe Thomas T Climent Victor V Armstrong Fraser A FA

Proceedings of the National Academy of Sciences of the United States of America 20120716 29

The extraordinary ability of Fe- and Ni-containing enzymes to catalyze rapid and efficient H(+)/H(2) interconversion--a property otherwise exclusive to platinum metals--has been investigated in a series of experiments combining variable-temperature protein film voltammetry with mathematical modeling. The results highlight important differences between the catalytic performance of [FeFe]-hydrogenases and [NiFe]-hydrogenases and justify a simple model for reversible catalytic electron flow in enzy ...[more]

PMID: 22802675

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