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Selenocyanate derived Se-incorporation into the nitrogenase Fe protein cluster.

ABSTRACT: The nitrogenase Fe protein mediates ATP-dependent electron transfer to the nitrogenase MoFe protein during nitrogen fixation, in addition to catalyzing MoFe protein-independent substrate (CO₂) reduction and facilitating MoFe protein metallocluster biosynthesis. The precise role(s) of the Fe protein Fe₄S₄ cluster in some of these processes remains ill-defined. Herein, we report crystallographic data demonstrating ATP-dependent chalcogenide exchange at the Fe₄S₄ cluster of the nitrogenase Fe protein when potassium selenocyanate is used as the selenium source, an unexpected result as the Fe protein cluster is not traditionally perceived as a site of substrate binding within nitrogenase. The observed chalcogenide exchange illustrates that this Fe₄S₄ cluster is capable of core substitution reactions under certain conditions, adding to the Fe protein's repertoire of unique properties.

SUBMITTER: Buscagan TM

PROVIDER: S-EPMC9462850 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature

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Selenocyanate derived Se-incorporation into the nitrogenase Fe protein cluster.

Buscagan Trixia M TM Kaiser Jens T JT Rees Douglas C DC

eLife 20220729

The nitrogenase Fe protein mediates ATP-dependent electron transfer to the nitrogenase MoFe protein during nitrogen fixation, in addition to catalyzing MoFe protein-independent substrate (CO2) reduction and facilitating MoFe protein metallocluster biosynthesis. The precise role(s) of the Fe protein Fe4S4 cluster in some of these processes remains ill-defined. Herein, we report crystallographic data demonstrating ATP-dependent chalcogenide exchange at the Fe4 ...[more]

PMID: 35904245

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