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Nitrogenase reactivity with P-cluster variants.

Yilin Hu·Mary C Corbett·Aaron W Fay·Jerome A Webber·Britt Hedman·Keith O Hodgson·Markus W Ribbe
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Abstract

Nitrogenase is a multicomponent metalloenzyme that catalyzes the conversion of atmospheric dinitrogen to ammonia. For decades, it has been generally believed that the [8Fe-7S] P-cluster of nitrogenase component 1 is indispensable for nitrogenase activity. In this study, we identified two catalytically active P-cluster variants by activity assays, metal analysis, and EPR spectroscopic studies. Further, we showed that both P-cluster variants resemble [4Fe-4S]-like centers based on x-ray absorption spectroscopic experiments. We believe that our findings challenge the dogma that the standard P-cluster is the only cluster species capable of supporting substrate reduction at the FeMo cofactor and provide important insights into the general mechanism of nitrogenase catalysis and assembly.

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Azotobacter vinelandiiCatalysisMetalloproteinsMolybdoferredoxinNitrogenaseJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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Yilin Hu, Mary C Corbett, Aaron W Fay, Jerome A Webber, Britt Hedman, Keith O Hodgson, Markus W Ribbe. 2005-09-15. Nitrogenase reactivity with P-cluster variants.. https://doi.org/10.1073/pnas.0506967102

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