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ATP-dependent substrate reduction at an [Fe8S9] double-cubane cluster.

ABSTRACT: Chemically demanding reductive conversions in biology, such as the reduction of dinitrogen to ammonia or the Birch-type reduction of aromatic compounds, depend on Fe/S-cluster-containing ATPases. These reductions are typically catalyzed by two-component systems, in which an Fe/S-cluster-containing ATPase energizes an electron to reduce a metal site on the acceptor protein that drives the reductive reaction. Here, we show a two-component system featuring a double-cubane [Fe8S9]-cluster [{Fe4S4(SCys)3}2(?2-S)]. The double-cubane-cluster-containing enzyme is capable of reducing small molecules, such as acetylene (C2H2), azide (N3-), and hydrazine (N2H4). We thus present a class of metalloenzymes akin in fold, metal clusters, and reactivity to nitrogenases.

SUBMITTER: Jeoung JH

PROVIDER: S-EPMC5866592 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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ATP-dependent substrate reduction at an [Fe8S9] double-cubane cluster.

Jeoung Jae-Hun JH Dobbek Holger H

Proceedings of the National Academy of Sciences of the United States of America 20180305 12

Chemically demanding reductive conversions in biology, such as the reduction of dinitrogen to ammonia or the Birch-type reduction of aromatic compounds, depend on Fe/S-cluster-containing ATPases. These reductions are typically catalyzed by two-component systems, in which an Fe/S-cluster-containing ATPase energizes an electron to reduce a metal site on the acceptor protein that drives the reductive reaction. Here, we show a two-component system featuring a double-cubane [Fe8S9</su ...[more]

PMID: 29507223

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