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Modeling the MoFe Nitrogenase System with Broken Symmetry Density Functional Theory

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Nitrogen Fixation

Part of the book series: Methods in Molecular Biology ((MIMB,volume 766))

Abstract

Density functional theory (DFT) represents a unified framework for gaining molecular level insight into molybdenum–iron (MoFe) nitrogenase. However, accurately describing the electronic structure of the spin-polarized and spin-coupled iron–molybdenum cofactor (FeMo-co) where N2 reduction occurs within MoFe nitrogenase is challenging. Therefore, the enhancement of DFT to include broken symmetry (BS-DFT) plus approximate spin projection has proven valuable because it provides a procedure to compute reliable geometries, energies, redox potentials, and quantities relevant to Mössbauer and ENDOR spectroscopies. After describing the theoretical tools necessary to obtain this information, we show by way of examples how BS-DFT is a very powerful partner to experiment. We expect that quantitative quantum chemical theory of this type will play an ever-increasing role in helping to decipher complex bioinorganic systems like those found in MoFe nitrogenase.

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Acknowledgments

The authors would like to acknowledge the other contributors to our nitrogenase work, whose names appear throughout the reference section. Most recently, Vladimir Pelmenschikov and David A. Case have made substantial contributions. We also gratefully acknowledge financial support by NIH grant GM039914.

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Authors and Affiliations

  1. Department of Molecular Biology, The Scripps Research Institute, La Jolla, CA, 92037, USA

    Gregory M. Sandala & Louis Noodleman

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  1. Gregory M. Sandala
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  2. Louis Noodleman
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Correspondence to Louis Noodleman .

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Editors and Affiliations

  1. , Dept Molecular Biology & Biochemistry, University of California, Irvine, Irvine, 92697, California, USA

    Markus W. Ribbe

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Sandala, G.M., Noodleman, L. (2011). Modeling the MoFe Nitrogenase System with Broken Symmetry Density Functional Theory. In: Ribbe, M. (eds) Nitrogen Fixation. Methods in Molecular Biology, vol 766. Humana Press. https://doi.org/10.1007/978-1-61779-194-9_19

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  • DOI: https://doi.org/10.1007/978-1-61779-194-9_19

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  • Publisher Name: Humana Press

  • Print ISBN: 978-1-61779-193-2

  • Online ISBN: 978-1-61779-194-9

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