1
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Roemelt C, Peredkov S, Neese F, Roemelt M, DeBeer S. Valence-to-core X-ray emission spectroscopy of transition metal tetrahalides: mechanisms governing intensities. Phys Chem Chem Phys 2024. [PMID: 38994715 DOI: 10.1039/d4cp00967c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/13/2024]
Abstract
Valence-to-core (VtC) X-ray emission spectroscopy offers the opportunity to probe the valence electronic structure of a system filtered by selection rules. From this, the nature of its ligands can be inferred. While a preceding 1s ionization creates a core hole, in VtC XES this core hole is filled with electrons from mainly ligand based orbitals. In this work, we investigated the trends in the observed VtC intensities for a series of transition metal halides, which spans the first row transition metals from manganese to copper. Further, with the aid of computational studies, we corroborated these trends and identified the mechanisms and factors that dictate the observed intensity trends. Small amounts of metal p contribution to the ligand orbitals are known to give rise to intensity of a VtC transition. By employing an LCAO (linear combination of atomic orbitals) approach, we were able to assess the amount of metal p contribution to the ligand molecular orbitals, as well as the role of the transition dipole moment and correlate these factors to the experimentally observed intensities. Finally, by employing an ano (atomic natural orbital) basis set within the calculations, the nature of the metal p contribution (3p vs. 4p) was qualitatively assessed and their trends discussed within the same transition metal halide series.
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Affiliation(s)
- Christina Roemelt
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany.
| | - Sergey Peredkov
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany.
| | - Frank Neese
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Michael Roemelt
- Humboldt University Berlin, Brook-Taylor-Str. 2, 12489 Berlin, Germany.
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany.
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2
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Hahn AW, Zsombor-Pindera J, Kennepohl P, DeBeer S. Introducing SpectraFit: An Open-Source Tool for Interactive Spectral Analysis. ACS OMEGA 2024; 9:23252-23265. [PMID: 38854548 PMCID: PMC11155667 DOI: 10.1021/acsomega.3c09262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 05/05/2024] [Accepted: 05/10/2024] [Indexed: 06/11/2024]
Abstract
In chemistry, analyzing spectra through peak fitting is a crucial task that helps scientists extract useful quantitative information about a sample's chemical composition or electronic structure. To make this process more efficient, we have developed a new open-source software tool called SpectraFit. This tool allows users to perform quick data fitting using expressions of distribution and linear functions through the command line interface (CLI) or Jupyter Notebook, which can run on Linux, Windows, and MacOS, as well as in a Docker container. As part of our commitment to good scientific practice, we have introduced an output file-locking system to ensure the accuracy and consistency of information. This system collects input data, results data, and the initial fitting model in a single file, promoting transparency, reproducibility, collaboration, and innovation. To demonstrate SpectraFit's user-friendly interface and the advantages of its output file-locking system, we are focusing on a series of previously published iron-sulfur dimers and their XAS spectra. We will show how to analyze the XAS spectra via CLI and in a Jupyter Notebook by simultaneously fitting multiple data sets using SpectraFit. Additionally, we will demonstrate how SpectraFit can be used as a black box and white box solution, allowing users to apply their own algorithms to engineer the data further. This publication, along with its Supporting Information and the Jupyter Notebook, serves as a tutorial to guide users through each step of the process. SpectraFit will streamline the peak fitting process and provide a convenient, standardized platform for users to share fitting models, which we hope will improve transparency and reproducibility in the field of spectroscopy.
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Affiliation(s)
- Anselm W. Hahn
- Max
Planck Institute for Chemical Energy Conversion, Stiftstraße 34-36, Mülheim an der Ruhr 45470, Germany
| | - Joseph Zsombor-Pindera
- Department
of Chemistry, University of Calgary, Calgary, AB T2N 1N4, Canada
- Department
of Chemistry, The University of British
Columbia, Vancouver, BC V6T 1Z1, Canada
| | - Pierre Kennepohl
- Department
of Chemistry, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Serena DeBeer
- Max
Planck Institute for Chemical Energy Conversion, Stiftstraße 34-36, Mülheim an der Ruhr 45470, Germany
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3
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Veronesi G, Pérard J, Clémancey M, Gerez C, Duverger Y, Kieffer I, Barras F, Gambarelli S, Blondin G, Ollagnier de Choudens S. Multimodal Spectroscopic Analysis of the Fe-S Clusters of the as-Isolated Escherichia coli SufBC 2D Complex. Inorg Chem 2024; 63:8730-8738. [PMID: 38687645 DOI: 10.1021/acs.inorgchem.4c00304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
Iron-sulfur (Fe-S) clusters are essential inorganic cofactors dedicated to a wide range of biological functions, including electron transfer and catalysis. Specialized multiprotein machineries present in all types of organisms support their biosynthesis. These machineries encompass a scaffold protein, on which Fe-S clusters are assembled before being transferred to cellular targets. Here, we describe the first characterization of the native Fe-S cluster of the anaerobically purified SufBC2D scaffold from Escherichia coli by XAS and Mössbauer, UV-visible absorption, and EPR spectroscopies. Interestingly, we propose that SufBC2D harbors two iron-sulfur-containing species, a [2Fe-2S] cluster and an as-yet unidentified species. Mutagenesis and biochemistry were used to propose amino acid ligands for the [2Fe-2S] cluster, supporting the hypothesis that both SufB and SufD are involved in the Fe-S cluster ligation. The [2Fe-2S] cluster can be transferred to ferredoxin in agreement with the SufBC2D scaffold function. These results are discussed in the context of Fe-S cluster biogenesis.
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Affiliation(s)
- Giulia Veronesi
- Univ. Grenoble Alpes, CNRS, CEA, IRIG, Laboratoire de Chimie et Biologie des Métaux, Grenoble F-38000, France
| | - Julien Pérard
- Univ. Grenoble Alpes, CNRS, CEA, IRIG, Laboratoire de Chimie et Biologie des Métaux, Grenoble F-38000, France
| | - Martin Clémancey
- Univ. Grenoble Alpes, CNRS, CEA, IRIG, Laboratoire de Chimie et Biologie des Métaux, Grenoble F-38000, France
| | - Catherine Gerez
- Univ. Grenoble Alpes, CNRS, CEA, IRIG, Laboratoire de Chimie et Biologie des Métaux, Grenoble F-38000, France
| | - Yohann Duverger
- Laboratoire de Chimie Bactérienne, UMR7243 Aix-Marseille Université CNRS, 31 Chemin Joseph Aiguier, Marseille 13009, France
| | - Isabelle Kieffer
- Univ. Grenoble Alpes, CNRS, IRD, Irstea, Météo France, OSUG, FAME, Grenoble 38000, France
| | - Frédéric Barras
- Institut Pasteur, Université de Paris, CNRS UMR 6047, Department of Microbiology, SAMe Unit, Paris 75724, France
| | - Serge Gambarelli
- Univ. Grenoble Alpes, CEA, CNRS, IRIG, SyMMES, Grenoble F-38000, France
| | - Geneviève Blondin
- Univ. Grenoble Alpes, CNRS, CEA, IRIG, Laboratoire de Chimie et Biologie des Métaux, Grenoble F-38000, France
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4
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Geoghegan BL, Bilyj JK, Bernhardt PV, DeBeer S, Cutsail GE. X-ray absorption and emission spectroscopy of N 2S 2 Cu(II)/(III) complexes. Dalton Trans 2024; 53:7828-7838. [PMID: 38624161 DOI: 10.1039/d4dt00085d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2024]
Abstract
This study investigates the influence of ligand charge on transition energies in a series of CuN2S2 complexes based on dithiocarbazate Schiff base ligands using Cu K-edge X-ray absorption spectroscopy (XAS) and Kβ valence-to-core (VtC) X-ray emission spectroscopy (XES). By comparing the formally Cu(II) complexes [CuII(HL1)] (HL12- = dimethyl pentane-2,4-diylidenebis[carbonodithiohydrazonate]) and [CuII(HL2)] (HL22- = dibenzyl pentane-2,4-diylidenebis[carbonodithiohydrazonate]) and the formally Cu(III) complex [CuIII(L2)], distinct changes in transition energies are observed, primarily attributed to the metal oxidation state. Density functional theory (DFT) calculations demonstrate how an increased negative charge on the deprotonated L23- ligand stabilizes the Cu(III) center through enhanced charge donation, modulating the core transition energies. Overall, significant shifts to higher energies are noted upon metal oxidation, emphasizing the importance of scrutinizing ligand structure in XAS/VtC XES analysis. The data further support the redox-innocent role of the Schiff base ligands and underscore the criticality of ligand protonation levels in future spectroscopic studies, particularly for catalytic intermediates. The combined XAS-VtC XES methodology validates the Cu(III) oxidation state assignment while offering insights into ligand protonation effects on core-level spectroscopic transitions.
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Affiliation(s)
- Blaise L Geoghegan
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany.
- Institute of Inorganic Chemistry, University of Duisburg-Essen, Universitätsstrasse 5-7, 45117 Essen, Germany
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, W12 0BZ, London, UK
| | - Jessica K Bilyj
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane 4072, Australia
| | - Paul V Bernhardt
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane 4072, Australia
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany.
| | - George E Cutsail
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany.
- Institute of Inorganic Chemistry, University of Duisburg-Essen, Universitätsstrasse 5-7, 45117 Essen, Germany
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5
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Wilson DWN, Fataftah MS, Mathe Z, Mercado BQ, DeBeer S, Holland PL. Three-Coordinate Nickel and Metal-Metal Interactions in a Heterometallic Iron-Sulfur Cluster. J Am Chem Soc 2024; 146:4013-4025. [PMID: 38308743 PMCID: PMC10993082 DOI: 10.1021/jacs.3c12157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2024]
Abstract
Biological multielectron reactions often are performed by metalloenzymes with heterometallic sites, such as anaerobic carbon monoxide dehydrogenase (CODH), which has a nickel-iron-sulfide cubane with a possible three-coordinate nickel site. Here, we isolate the first synthetic iron-sulfur clusters having a nickel atom with only three donors, showing that this structural feature is feasible. These have a core with two tetrahedral irons, one octahedral tungsten, and a three-coordinate nickel connected by sulfide and thiolate bridges. Electron paramagnetic resonance (EPR), Mössbauer, and superconducting quantum interference device (SQUID) data are combined with density functional theory (DFT) computations to show how the electronic structure of the cluster arises from strong magnetic coupling between the Ni, Fe, and W sites. X-ray absorption spectroscopy, together with spectroscopically validated DFT analysis, suggests that the electronic structure can be described with a formal Ni1+ atom participating in a nonpolar Ni-W σ-bond. This metal-metal bond, which minimizes spin density at Ni1+, is conserved in two cluster oxidation states. Fe-W bonding is found in all clusters, in one case stabilizing a local non-Hund state at tungsten. Based on these results, we compare different M-M interactions and speculate that other heterometallic clusters, including metalloenzyme active sites, could likewise store redox equivalents and stabilize low-valent metal centers through metal-metal bonding.
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Affiliation(s)
- Daniel W. N. Wilson
- Department of Chemistry, Yale University, 225 Prospect St., New Haven, Connecticut 06520, USA
| | - Majed S. Fataftah
- Department of Chemistry, Yale University, 225 Prospect St., New Haven, Connecticut 06520, USA
| | - Zachary Mathe
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Brandon Q. Mercado
- Department of Chemistry, Yale University, 225 Prospect St., New Haven, Connecticut 06520, USA
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Patrick L. Holland
- Department of Chemistry, Yale University, 225 Prospect St., New Haven, Connecticut 06520, USA
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6
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Scott AG, Galico DA, Bogacz I, Oyala PH, Yano J, Suturina EA, Murugesu M, Agapie T. High-Spin and Reactive Fe 13 Cluster with Exposed Metal Sites. Angew Chem Int Ed Engl 2023; 62:e202313880. [PMID: 37871234 PMCID: PMC10962695 DOI: 10.1002/anie.202313880] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Revised: 10/23/2023] [Accepted: 10/23/2023] [Indexed: 10/25/2023]
Abstract
Atomically defined large metal clusters have applications in new reaction development and preparation of materials with tailored properties. Expanding the synthetic toolbox for reactive high nuclearity metal complexes, we report a new class of Fe clusters, Tp*4 W4 Fe13 S12 , displaying a Fe13 core with M-M bonds that has precedent only in main group and late metal chemistry. M13 clusters with closed shell electron configurations can show significant stability and have been classified as superatoms. In contrast, Tp*4 W4 Fe13 S12 displays a large spin ground state of S=13. This compound performs small molecule activations involving the transfer of up to 12 electrons resulting in significant cluster rearrangements.
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Affiliation(s)
- Anna G. Scott
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125 (USA)
| | - Diogo Alves Galico
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1 N6 N5 (Canada)
| | - Isabel Bogacz
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory Berkeley, CA 94720 (USA)
| | - Paul H. Oyala
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125 (USA)
| | - Junko Yano
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory Berkeley, CA 94720 (USA)
| | | | - Muralee Murugesu
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1 N6 N5 (Canada)
| | - Theodor Agapie
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125 (USA)
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7
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Yogendra S, Wilson DWN, Hahn AW, Weyhermüller T, Van Stappen C, Holland P, DeBeer S. Sulfur-Ligated [2Fe-2C] Clusters as Synthetic Model Systems for Nitrogenase. Inorg Chem 2023; 62:2663-2671. [PMID: 36715662 PMCID: PMC9930126 DOI: 10.1021/acs.inorgchem.2c03693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Indexed: 01/31/2023]
Abstract
Metal clusters featuring carbon and sulfur donors have coordination environments comparable to the active site of nitrogenase enzymes. Here, we report a series of di-iron clusters supported by the dianionic yldiide ligands, in which the Fe sites are bridged by two μ2-C atoms and four pendant S donors.The [L2Fe2] (L = {[Ph2P(S)]2C}2-) cluster is isolable in two oxidation levels, all-ferrous Fe2II and mixed-valence FeIIFeIII. The mixed-valence cluster displays two peaks in the Mössbauer spectra, indicating slow electron transfer between the two sites. The addition of the Lewis base 4-dimethylaminopyridine to the Fe2II cluster results in coordination with only one of the two Fe sites, even in the presence of an excess base. Conversely, the cluster reacts with 8 equiv of isocyanide tBuNC to give a monometallic complex featuring a new C-C bond between the ligand backbone and the isocyanide. The electronic structure descriptions of these complexes are further supported by X-ray absorption and resonant X-ray emission spectroscopies.
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Affiliation(s)
- Sivathmeehan Yogendra
- Max
Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Daniel W. N. Wilson
- Department
of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520, United States
| | - Anselm W. Hahn
- Max
Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Thomas Weyhermüller
- Max
Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Casey Van Stappen
- Max
Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Patrick Holland
- Department
of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06520, United States
| | - Serena DeBeer
- Max
Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
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8
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Decamps L, Rice DB, DeBeer S. An Fe 6 C Core in All Nitrogenase Cofactors. Angew Chem Int Ed Engl 2022; 61:e202209190. [PMID: 35975943 PMCID: PMC9826452 DOI: 10.1002/anie.202209190] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Indexed: 01/11/2023]
Abstract
The biological process of dinitrogen reduction to ammonium occurs at the cofactors of nitrogenases, the only enzymes that catalyze this challenging chemical reaction. Three types of nitrogenases have been described, named according to the heterometal in their cofactor: molybdenum, vanadium or iron nitrogenases. Spectroscopic and structural characterization allowed the unambiguous identification of the cofactors of molybdenum and vanadium nitrogenases and revealed a central μ6 -carbide in both of them. Although genetic studies suggested that the cofactor of the iron nitrogenase contains a similar Fe6 C core, this has not been experimentally demonstrated. Here we report Valence-to-Core X-ray Emission Spectroscopy providing experimental evidence that this cofactor contains a carbide, thereby making the Fe6 C core a feature of all nitrogenase cofactors.
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Affiliation(s)
- Laure Decamps
- Department of Inorganic SpectroscopyMax Planck Institute for Chemical Energy ConversionStiftstrasse 34–3645470Mülheim an derRuhrGermany
| | - Derek B. Rice
- Department of Inorganic SpectroscopyMax Planck Institute for Chemical Energy ConversionStiftstrasse 34–3645470Mülheim an derRuhrGermany
| | - Serena DeBeer
- Department of Inorganic SpectroscopyMax Planck Institute for Chemical Energy ConversionStiftstrasse 34–3645470Mülheim an derRuhrGermany
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9
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Srour B, Gervason S, Hoock MH, Monfort B, Want K, Larkem D, Trabelsi N, Landrot G, Zitolo A, Fonda E, Etienne E, Gerbaud G, Müller CS, Oltmanns J, Gordon JB, Yadav V, Kleczewska M, Jelen M, Toledano MB, Dutkiewicz R, Goldberg DP, Schünemann V, Guigliarelli B, Burlat B, Sizun C, D'Autréaux B. Iron Insertion at the Assembly Site of the ISCU Scaffold Protein Is a Conserved Process Initiating Fe-S Cluster Biosynthesis. J Am Chem Soc 2022; 144:17496-17515. [PMID: 36121382 PMCID: PMC10163866 DOI: 10.1021/jacs.2c06338] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Iron-sulfur (Fe-S) clusters are prosthetic groups of proteins biosynthesized on scaffold proteins by highly conserved multi-protein machineries. Biosynthesis of Fe-S clusters into the ISCU scaffold protein is initiated by ferrous iron insertion, followed by sulfur acquisition, via a still elusive mechanism. Notably, whether iron initially binds to the ISCU cysteine-rich assembly site or to a cysteine-less auxiliary site via N/O ligands remains unclear. We show here by SEC, circular dichroism (CD), and Mössbauer spectroscopies that iron binds to the assembly site of the monomeric form of prokaryotic and eukaryotic ISCU proteins via either one or two cysteines, referred to the 1-Cys and 2-Cys forms, respectively. The latter predominated at pH 8.0 and correlated with the Fe-S cluster assembly activity, whereas the former increased at a more acidic pH, together with free iron, suggesting that it constitutes an intermediate of the iron insertion process. Iron not binding to the assembly site was non-specifically bound to the aggregated ISCU, ruling out the existence of a structurally defined auxiliary site in ISCU. Characterization of the 2-Cys form by site-directed mutagenesis, CD, NMR, X-ray absorption, Mössbauer, and electron paramagnetic resonance spectroscopies showed that the iron center is coordinated by four strictly conserved amino acids of the assembly site, Cys35, Asp37, Cys61, and His103, in a tetrahedral geometry. The sulfur receptor Cys104 was at a very close distance and apparently bound to the iron center when His103 was missing, which may enable iron-dependent sulfur acquisition. Altogether, these data provide the structural basis to elucidate the Fe-S cluster assembly process and establish that the initiation of Fe-S cluster biosynthesis by insertion of a ferrous iron in the assembly site of ISCU is a conserved mechanism.
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Affiliation(s)
- Batoul Srour
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Sylvain Gervason
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Maren Hellen Hoock
- Fachbereich Physik, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 56, 67663 Kaiserslautern, Germany
| | - Beata Monfort
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Kristian Want
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Djabir Larkem
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Nadine Trabelsi
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Gautier Landrot
- Synchrotron SOLEIL, L'Orme des Merisiers, BP48 Saint Aubin 91192 Gif-Sur-Yvette, France
| | - Andrea Zitolo
- Synchrotron SOLEIL, L'Orme des Merisiers, BP48 Saint Aubin 91192 Gif-Sur-Yvette, France
| | - Emiliano Fonda
- Synchrotron SOLEIL, L'Orme des Merisiers, BP48 Saint Aubin 91192 Gif-Sur-Yvette, France
| | - Emilien Etienne
- Aix Marseille Univ, CNRS, Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP), 31 Chemin Joseph Aiguier, 13402 Marseille, France
| | - Guillaume Gerbaud
- Aix Marseille Univ, CNRS, Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP), 31 Chemin Joseph Aiguier, 13402 Marseille, France
| | - Christina Sophia Müller
- Fachbereich Physik, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 56, 67663 Kaiserslautern, Germany
| | - Jonathan Oltmanns
- Fachbereich Physik, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 56, 67663 Kaiserslautern, Germany
| | - Jesse B Gordon
- Department of Chemistry, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland 21218, United States
| | - Vishal Yadav
- Department of Chemistry, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland 21218, United States
| | - Malgorzata Kleczewska
- Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307 Gdansk, Poland
| | - Marcin Jelen
- Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307 Gdansk, Poland
| | - Michel B Toledano
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Rafal Dutkiewicz
- Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307 Gdansk, Poland
| | - David P Goldberg
- Department of Chemistry, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland 21218, United States
| | - Volker Schünemann
- Fachbereich Physik, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 56, 67663 Kaiserslautern, Germany
| | - Bruno Guigliarelli
- Aix Marseille Univ, CNRS, Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP), 31 Chemin Joseph Aiguier, 13402 Marseille, France
| | - Bénédicte Burlat
- Aix Marseille Univ, CNRS, Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP), 31 Chemin Joseph Aiguier, 13402 Marseille, France
| | - Christina Sizun
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris Saclay, Avenue de La Terrasse, 91190 Gif-sur-Yvette, France
| | - Benoit D'Autréaux
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
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10
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Cutsail GE, Banerjee R, Rice DB, McCubbin Stepanic O, Lipscomb JD, DeBeer S. Determination of the iron(IV) local spin states of the Q intermediate of soluble methane monooxygenase by Kβ X-ray emission spectroscopy. J Biol Inorg Chem 2022; 27:573-582. [PMID: 35988092 PMCID: PMC9470658 DOI: 10.1007/s00775-022-01953-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 08/07/2022] [Indexed: 11/29/2022]
Abstract
Soluble methane monooxygenase (sMMO) facilitates the conversion of methane to methanol at a non-heme FeIV2 intermediate MMOHQ, which is formed in the active site of the sMMO hydroxylase component (MMOH) during the catalytic cycle. Other biological systems also employ high-valent FeIV sites in catalysis; however, MMOHQ is unique as Nature’s only identified FeIV2 intermediate. Previous 57Fe Mössbauer spectroscopic studies have shown that MMOHQ employs antiferromagnetic coupling of the two FeIV sites to yield a diamagnetic cluster. Unfortunately, this lack of net spin prevents the determination of the local spin state (Sloc) of each of the irons by most spectroscopic techniques. Here, we use Fe Kβ X-ray emission spectroscopy (XES) to characterize the local spin states of the key intermediates of the sMMO catalytic cycle, including MMOHQ trapped by rapid-freeze-quench techniques. A pure XES spectrum of MMOHQ is obtained by subtraction of the contributions from other reaction cycle intermediates with the aid of Mössbauer quantification. Comparisons of the MMOHQ spectrum with those of known Sloc = 1 and Sloc = 2 FeIV sites in chemical and biological models reveal that MMOHQ possesses Sloc = 2 iron sites. This experimental determination of the local spin state will help guide future computational and mechanistic studies of sMMO catalysis.
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Affiliation(s)
- George E Cutsail
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470, Mülheim an der Ruhr, Germany.
- Institute of Inorganic Chemistry, University of Duisburg-Essen, Universitätsstrasse 5-7, 45117, Essen, Germany.
| | - Rahul Banerjee
- Department of Biochemistry Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Derek B Rice
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470, Mülheim an der Ruhr, Germany
| | - Olivia McCubbin Stepanic
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470, Mülheim an der Ruhr, Germany
| | - John D Lipscomb
- Department of Biochemistry Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470, Mülheim an der Ruhr, Germany.
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11
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Decamps L, Rice D, DeBeer S. An Fe6C Core in All Nitrogenase Cofactors. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202209190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Laure Decamps
- Max-Planck-Institute for Chemical Energy Conversion: Max-Planck-Institut fur chemische Energiekonversion Inorganic Spectroscopy GERMANY
| | - Derek Rice
- Max-Planck-Institute for Chemical Energy Conversion: Max-Planck-Institut fur chemische Energiekonversion Inorganic Spectroscopy GERMANY
| | - Serena DeBeer
- MPI CEC Molecular Theory and Spectroscopy Stidtstr. 34-36 45470 Muelheim an der Ruhr GERMANY
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12
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Cutsail III GE, DeBeer S. Challenges and Opportunities for Applications of Advanced X-ray Spectroscopy in Catalysis Research. ACS Catal 2022. [DOI: 10.1021/acscatal.2c01016] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- George E. Cutsail III
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
- Institute of Inorganic Chemistry, University of Duisburg-Essen, Universitätsstr. 5-7, 45117 Essen, Germany
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
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13
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Cząstka K, Oughli AA, Rüdiger O, DeBeer S. Enzymatic X-ray absorption spectroelectrochemistry. Faraday Discuss 2022; 234:214-231. [PMID: 35142778 DOI: 10.1039/d1fd00079a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The ability to observe the changes that occur at an enzyme active site during electrocatalysis can provide very valuable information for understanding the mechanism and ultimately aid in catalyst design. Herein, we discuss the development of X-ray absorption spectroscopy (XAS) in combination with electrochemistry for operando studies of enzymatic systems. XAS has had a long history of enabling geometric and electronic structural insights into the catalytic active sites of enzymes, however, XAS combined with electrochemistry (XA-SEC) has been exceedingly rare in bioinorganic applications. Herein, we discuss the challenges and opportunities of applying operando XAS to enzymatic electrocatalysts. The challenges due to the low concentration of the photoabsorber and the instability of the protein in the X-ray beam are discussed. Methods for immobilizing enzymes on the electrodes, while maintaining full redox control are highlighted. A case study of combined XAS and electrochemistry applied to a [NiFe] hydrogenase is presented. By entrapping the [NiFe] hydrogenase in a redox polymer, relatively high protein concentrations can be achieved on the electrode surface, while maintaining redox control. Overall, it is demonstrated that the experiments are feasible, but require precise redox control over the majority of the absorber atoms and careful controls to discriminate between electrochemically-driven changes and beam damage. Opportunities for future applications are discussed.
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Affiliation(s)
- Karolina Cząstka
- Max Planck Institute for Chemical Energy Conversion, Mülheim an der Ruhr, DE, Germany.
| | - Alaa A Oughli
- Technical University Munich, Campus Straubing for Biotechnology and Sustainability, Uferstraße 53, 94315 Straubing, Germany
| | - Olaf Rüdiger
- Max Planck Institute for Chemical Energy Conversion, Mülheim an der Ruhr, DE, Germany.
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion, Mülheim an der Ruhr, DE, Germany.
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14
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Chatterjee S, Harden I, Bistoni G, Castillo RG, Chabbra S, van Gastel M, Schnegg A, Bill E, Birrell JA, Morandi B, Neese F, DeBeer S. A Combined Spectroscopic and Computational Study on the Mechanism of Iron-Catalyzed Aminofunctionalization of Olefins Using Hydroxylamine Derived N-O Reagent as the "Amino" Source and "Oxidant". J Am Chem Soc 2022; 144:2637-2656. [PMID: 35119853 PMCID: PMC8855425 DOI: 10.1021/jacs.1c11083] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
![]()
Herein, we study
the mechanism of iron-catalyzed direct synthesis
of unprotected aminoethers from olefins by a hydroxyl amine derived
reagent using a wide range of analytical and spectroscopic techniques
(Mössbauer, Electron Paramagnetic Resonance, Ultra-Violet Visible
Spectroscopy, X-ray Absorption, Nuclear Resonance Vibrational Spectroscopy,
and resonance Raman) along with high-level quantum chemical calculations.
The hydroxyl amine derived triflic acid salt acts as the “oxidant”
as well as “amino” group donor. It activates the high-spin
Fe(II) (St = 2) catalyst [Fe(acac)2(H2O)2] (1) to generate
a high-spin (St = 5/2) intermediate (Int I), which decays to a second intermediate (Int II) with St = 2. The analysis of spectroscopic
and computational data leads to the formulation of Int I as [Fe(III)(acac)2-N-acyloxy] (an alkyl-peroxo-Fe(III)
analogue). Furthermore, Int II is formed by N–O
bond homolysis. However, it does not generate a high-valent
Fe(IV)(NH) species (a Fe(IV)(O) analogue), but instead a high-spin
Fe(III) center which is strongly antiferromagnetically coupled (J = −524 cm–1) to an iminyl radical,
[Fe(III)(acac)2-NH·], giving St = 2. Though Fe(NH) complexes as isoelectronic surrogates
to Fe(O) functionalities are known, detection of a high-spin Fe(III)-N-acyloxy intermediate (Int I), which undergoes
N–O bond cleavage to generate the active iron–nitrogen
intermediate (Int II), is unprecedented. Relative to
Fe(IV)(O) centers, Int II features a weak elongated Fe–N
bond which, together with the unpaired electron density along the
Fe–N bond vector, helps to rationalize its propensity for N-transfer reactions onto styrenyl olefins, resulting in
the overall formation of aminoethers. This study thus demonstrates
the potential of utilizing the iron-coordinated nitrogen-centered
radicals as powerful reactive intermediates in catalysis.
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Affiliation(s)
- Sayanti Chatterjee
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany.,Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Ingolf Harden
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Giovanni Bistoni
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Rebeca G Castillo
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Sonia Chabbra
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Maurice van Gastel
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Alexander Schnegg
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Eckhard Bill
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - James A Birrell
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Bill Morandi
- ETH Zürich, Vladimir-Prelog-Weg 3, HCI, 8093 Zürich, Switzerland.,Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Frank Neese
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
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15
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Stabilization of intermediate spin states in mixed-valent diiron dichalcogenide complexes. Nat Chem 2022; 14:328-333. [PMID: 35058610 PMCID: PMC8898764 DOI: 10.1038/s41557-021-00853-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 11/03/2021] [Indexed: 11/24/2022]
Abstract
The electronic structure and ground spin states, S, observed for mixed-valent iron–sulfur dimers (FeII-FeIII) are typically determined by the Heisenberg exchange interaction, J, that couples the magnetic interaction of the two metal centres either ferromagnetically (J > 0, S = 9/2) or antiferromagnetically (J < 0, S = 1/2). In the case of antiferromagnetically coupled iron centres, stabilization of the high-spin S = 9/2 ground state is also feasible through a Heisenberg double-exchange interaction, B, which lifts the degeneracy of the Heisenberg spin states. This theorem also predicts intermediate spin states for mixed-valent dimers, but those have so far remained elusive. Herein, we describe the structural, electron paramagnetic resonance and Mössbauer spectroscopic, and magnetic characterization of a series of mixed-valent complexes featuring [Fe2Q2]+ (Q = S2–, Se2–, Te2–), where the Se and Te complexes favour S = 3/2 spin states. The incorporation of heavier chalcogenides in this series reveals a delicate balance of antiferromagnetic coupling, Heisenberg double-exchange and vibronic coupling. ![]()
Despite extensive investigations of mixed-valence complexes, molecules with intermediate spin states have remained elusive. Now, selenium- and tellurium-bridged mixed-valent iron dimers have been prepared in which a balance of Heisenberg exchange and double-exchange coupling of the unpaired electron, combined with moderate vibronic contributions, stabilizes S = 3/2 ground spin states.
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16
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Geoghegan BL, Liu Y, Peredkov S, Dechert S, Meyer F, DeBeer S, Cutsail GE. Combining Valence-to-Core X-ray Emission and Cu K-edge X-ray Absorption Spectroscopies to Experimentally Assess Oxidation State in Organometallic Cu(I)/(II)/(III) Complexes. J Am Chem Soc 2022; 144:2520-2534. [PMID: 35050605 PMCID: PMC8855422 DOI: 10.1021/jacs.1c09505] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
A series of organometallic
copper complexes in formal oxidation
states ranging from +1 to +3 have been characterized by a combination
of Cu K-edge X-ray absorption (XAS) and Cu Kβ valence-to-core
X-ray emission spectroscopies (VtC XES). Each formal oxidation state
exhibits distinctly different XAS and VtC XES transition energies
due to the differences in the Cu Zeff, concomitant with
changes in physical oxidation state from +1 to +2 to +3. Herein, we
demonstrate the sensitivity of XAS and VtC XES to the physical oxidation
states of a series of N-heterocyclic carbene (NHC) ligated organocopper
complexes. We then extend these methods to the study of the [Cu(CF3)4]− ion. Complemented by computational
methods, the observed spectral transitions are correlated with the
electronic structure of the complexes and the Cu Zeff.
These calculations demonstrate that a contraction of the Cu 1s orbitals
to deeper binding energy upon oxidation of the Cu center manifests
spectroscopically as a stepped increase in the energy of both XAS
and Kβ2,5 emission features with increasing formal
oxidation state within the [Cun+(NHC2)]n+ series. The newly synthesized Cu(III) cation
[CuIII(NHC4)]3+ exhibits spectroscopic
features and an electronic structure remarkably similar to [Cu(CF3)4]−, supporting a physical oxidation
state assignment of low-spin d8 Cu(III) for [Cu(CF3)4]−. Combining XAS and VtC XES
further demonstrates the necessity of combining multiple spectroscopies
when investigating the electronic structures of highly covalent copper
complexes, providing a template for future investigations into both
synthetic and biological metal centers.
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Affiliation(s)
- Blaise L. Geoghegan
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
- Institute of Inorganic Chemistry, University of Duisburg-Essen, Universitätsstrasse 5-7, 45117 Essen, Germany
| | - Yang Liu
- Institute of Inorganic Chemistry, University of Göttingen, Tammannstrasse 4, 37077 Göttingen, Germany
| | - Sergey Peredkov
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Sebastian Dechert
- Institute of Inorganic Chemistry, University of Göttingen, Tammannstrasse 4, 37077 Göttingen, Germany
| | - Franc Meyer
- Institute of Inorganic Chemistry, University of Göttingen, Tammannstrasse 4, 37077 Göttingen, Germany
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - George E. Cutsail
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
- Institute of Inorganic Chemistry, University of Duisburg-Essen, Universitätsstrasse 5-7, 45117 Essen, Germany
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17
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Van Stappen C, Jiménez-Vicente E, Pérez-González A, Yang ZY, Seefeldt LC, DeBeer S, Dean DR, Decamps L. A Conformational Role for NifW in the Maturation of Molybdenum Nitrogenase P-cluster. Chem Sci 2022; 13:3489-3500. [PMID: 35432878 PMCID: PMC8943848 DOI: 10.1039/d1sc06418e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 02/28/2022] [Indexed: 12/03/2022] Open
Abstract
Reduction of dinitrogen by molybdenum nitrogenase relies on complex metalloclusters: the [8Fe:7S] P-cluster and the [7Fe:9S:Mo:C:homocitrate] FeMo-cofactor. Although both clusters bear topological similarities and require the reductive fusion of [4Fe:4S] sub-clusters to achieve their respective assemblies, P-clusters are assembled directly on the NifD2K2 polypeptide prior to the insertion of FeMo-co, which is fully assembled separately from NifD2K2. P-cluster maturation involves the iron protein NifH2 as well as several accessory proteins, whose role has not been elucidated. In the present work, two NifD2K2 species bearing immature P-clusters were isolated from an Azotobacter vinelandii strain in which the genes encoding NifH and the accessory protein NifZ were deleted, and characterized by X-ray absorption spectroscopy and EPR. These analyses showed that both NifD2K2 complexes harbor clusters that are electronically and structurally similar, with each NifDK unit containing two [4Fe:4S]2+/+ clusters. Binding of the accessory protein NifW parallels a decrease in the distance between these clusters, as well as a subtle change in their coordination. These results support a conformational role for NifW in P-cluster biosynthesis, bringing the two [4Fe:4S] precursors closer prior to their fusion, which may be crucial in challenging cellular contexts. Upon binding of NifW, a subtle conformation change occurs in NifD2K2, decreasing the distance between the two [4Fe:4S] clusters precursors of the P-cluster in nitrogenase.![]()
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Affiliation(s)
- Casey Van Stappen
- Max Planck Institute for Chemical Energy Conversion Stiftstrasse 34-36 45470 Mülheim an der Ruhr Germany
| | - Emilio Jiménez-Vicente
- Department of Biochemistry, Virginia Polytechnic Institute and State University Blacksburg VA 24061 USA
| | - Ana Pérez-González
- Department of Biochemistry, Virginia Polytechnic Institute and State University Blacksburg VA 24061 USA
| | - Zhi-Yong Yang
- Department of Chemistry and Biochemistry, Utah State University Logan UT 84322 USA
| | - Lance C Seefeldt
- Department of Chemistry and Biochemistry, Utah State University Logan UT 84322 USA
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion Stiftstrasse 34-36 45470 Mülheim an der Ruhr Germany
| | - Dennis R Dean
- Department of Biochemistry, Virginia Polytechnic Institute and State University Blacksburg VA 24061 USA
| | - Laure Decamps
- Max Planck Institute for Chemical Energy Conversion Stiftstrasse 34-36 45470 Mülheim an der Ruhr Germany
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18
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Liang Q, DeMuth JC, Radović A, Wolford NJ, Neidig ML, Song D. [2Fe-2S] Cluster Supported by Redox-Active o-Phenylenediamide Ligands and Its Application toward Dinitrogen Reduction. Inorg Chem 2021; 60:13811-13820. [PMID: 34043353 DOI: 10.1021/acs.inorgchem.1c00683] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
As prevalent cofactors in living organisms, iron-sulfur clusters participate in not only the electron-transfer processes but also the biosynthesis of other cofactors. Many synthetic iron-sulfur clusters have been used in model studies, aiming to mimic their biological functions and to gain mechanistic insight into the related biological systems. The smallest [2Fe-2S] clusters are typically used for one-electron processes because of their limited capacity. Our group is interested in functionalizing small iron-sulfur clusters with redox-active ligands to enhance their electron storage capacity, because such functionalized clusters can potentially mediate multielectron chemical transformations. Herein we report the synthesis, structural characterization, and catalytic activity of a diferric [2Fe-2S] cluster functionalized with two o-phenylenediamide ligands. The electrochemical and chemical reductions of such a cluster revealed rich redox chemistry. The functionalized diferric cluster can store up to four electrons reversibly, where the first two reduction events are ligand-based and the remainder metal-based. The diferric [2Fe-2S] cluster displays catalytic activity toward silylation of dinitrogen, affording up to 88 equiv of the amine product per iron center.
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Affiliation(s)
- Qiuming Liang
- Davenport Chemical Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
| | - Joshua C DeMuth
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Aleksa Radović
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Nikki J Wolford
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Michael L Neidig
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Datong Song
- Davenport Chemical Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
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19
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Castillo RG, Hahn AW, Van Kuiken BE, Henthorn JT, McGale J, DeBeer S. Probing Physical Oxidation State by Resonant X-ray Emission Spectroscopy: Applications to Iron Model Complexes and Nitrogenase. Angew Chem Int Ed Engl 2021; 60:10112-10121. [PMID: 33497500 PMCID: PMC8252016 DOI: 10.1002/anie.202015669] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Indexed: 11/07/2022]
Abstract
The ability of resonant X-ray emission spectroscopy (XES) to recover physical oxidation state information, which may often be ambiguous in conventional X-ray spectroscopy, is demonstrated. By combining Kβ XES with resonant excitation in the XAS pre-edge region, resonant Kβ XES (or 1s3p RXES) data are obtained, which probe the 3dn+1 final-state configuration. Comparison of the non-resonant and resonant XES for a series of high-spin ferrous and ferric complexes shows that oxidation state assignments that were previously unclear are now easily made. The present study spans iron tetrachlorides, iron sulfur clusters, and the MoFe protein of nitrogenase. While 1s3p RXES studies have previously been reported, to our knowledge, 1s3p RXES has not been previously utilized to resolve questions of metal valency in highly covalent systems. As such, the approach presented herein provides chemists with means to more rigorously and quantitatively address challenging electronic-structure questions.
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Affiliation(s)
- Rebeca G. Castillo
- Department of Inorganic SpectroscopyMax Planck Institute for Chemical Energy ConversionStiftstrasse 34–3645470Mülheim an der RuhrGermany
| | - Anselm W. Hahn
- Department of Inorganic SpectroscopyMax Planck Institute for Chemical Energy ConversionStiftstrasse 34–3645470Mülheim an der RuhrGermany
| | | | - Justin T. Henthorn
- Department of Inorganic SpectroscopyMax Planck Institute for Chemical Energy ConversionStiftstrasse 34–3645470Mülheim an der RuhrGermany
| | - Jeremy McGale
- Department of Inorganic SpectroscopyMax Planck Institute for Chemical Energy ConversionStiftstrasse 34–3645470Mülheim an der RuhrGermany
| | - Serena DeBeer
- Department of Inorganic SpectroscopyMax Planck Institute for Chemical Energy ConversionStiftstrasse 34–3645470Mülheim an der RuhrGermany
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20
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Castillo RG, Hahn AW, Van Kuiken BE, Henthorn JT, McGale J, DeBeer S. Probing Physical Oxidation State by Resonant X‐ray Emission Spectroscopy: Applications to Iron Model Complexes and Nitrogenase. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202015669] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Rebeca G. Castillo
- Department of Inorganic Spectroscopy Max Planck Institute for Chemical Energy Conversion Stiftstrasse 34–36 45470 Mülheim an der Ruhr Germany
| | - Anselm W. Hahn
- Department of Inorganic Spectroscopy Max Planck Institute for Chemical Energy Conversion Stiftstrasse 34–36 45470 Mülheim an der Ruhr Germany
| | | | - Justin T. Henthorn
- Department of Inorganic Spectroscopy Max Planck Institute for Chemical Energy Conversion Stiftstrasse 34–36 45470 Mülheim an der Ruhr Germany
| | - Jeremy McGale
- Department of Inorganic Spectroscopy Max Planck Institute for Chemical Energy Conversion Stiftstrasse 34–36 45470 Mülheim an der Ruhr Germany
| | - Serena DeBeer
- Department of Inorganic Spectroscopy Max Planck Institute for Chemical Energy Conversion Stiftstrasse 34–36 45470 Mülheim an der Ruhr Germany
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21
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Rosenbach H, Walla E, Cutsail GE, Birrell JA, Pascual-Ortiz M, DeBeer S, Fleig U, Span I. The Asp1 pyrophosphatase from S. pombe hosts a [2Fe-2S] 2+ cluster in vivo. J Biol Inorg Chem 2021; 26:93-108. [PMID: 33544225 PMCID: PMC8038993 DOI: 10.1007/s00775-020-01840-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 11/29/2020] [Indexed: 11/25/2022]
Abstract
The Schizosaccharomyces pombe Asp1 protein is a bifunctional kinase/pyrophosphatase that belongs to the highly conserved eukaryotic diphosphoinositol pentakisphosphate kinase PPIP5K/Vip1 family. The N-terminal Asp1 kinase domain generates specific high-energy inositol pyrophosphate (IPP) molecules, which are hydrolyzed by the C-terminal Asp1 pyrophosphatase domain (Asp1365-920). Thus, Asp1 activities regulate the intracellular level of a specific class of IPP molecules, which control a wide number of biological processes ranging from cell morphogenesis to chromosome transmission. Recently, it was shown that chemical reconstitution of Asp1371-920 leads to the formation of a [2Fe-2S] cluster; however, the biological relevance of the cofactor remained under debate. In this study, we provide evidence for the presence of the Fe-S cluster in Asp1365-920 inside the cell. However, we show that the Fe-S cluster does not influence Asp1 pyrophosphatase activity in vitro or in vivo. Characterization of the as-isolated protein by electronic absorption spectroscopy, mass spectrometry, and X-ray absorption spectroscopy is consistent with the presence of a [2Fe-2S]2+ cluster in the enzyme. Furthermore, we have identified the cysteine ligands of the cluster. Overall, our work reveals that Asp1 contains an Fe-S cluster in vivo that is not involved in its pyrophosphatase activity.
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Affiliation(s)
- Hannah Rosenbach
- Institut Für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, 40225, Düsseldorf, Germany
| | - Eva Walla
- Lehrstuhl Für Funktionelle Genomforschung Der Mikroorganismen, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, 40225, Düsseldorf, Germany
| | - George E Cutsail
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470, Mülheim an der Ruhr, Germany
| | - James A Birrell
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470, Mülheim an der Ruhr, Germany
| | - Marina Pascual-Ortiz
- Department of Biomedical Sciences, Faculty of Health Sciences, Universidad Cardenal Herrera, CEU Universities, 46113, Valencia, Spain
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470, Mülheim an der Ruhr, Germany
| | - Ursula Fleig
- Lehrstuhl Für Funktionelle Genomforschung Der Mikroorganismen, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, 40225, Düsseldorf, Germany.
| | - Ingrid Span
- Institut Für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, 40225, Düsseldorf, Germany.
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22
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Phu PN, Gutierrez CE, Kundu S, Sokaras D, Kroll T, Warren TH, Stieber SCE. Quantification of Ni-N-O Bond Angles and NO Activation by X-ray Emission Spectroscopy. Inorg Chem 2021; 60:736-744. [PMID: 33373520 DOI: 10.1021/acs.inorgchem.0c02724] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A series of β-diketiminate Ni-NO complexes with a range of NO binding modes and oxidation states were studied by X-ray emission spectroscopy (XES). The results demonstrate that XES can directly probe and distinguish end-on vs side-on NO coordination modes as well as one-electron NO reduction. Density functional theory (DFT) calculations show that the transition from the NO 2s2s σ* orbital has higher intensity for end-on NO coordination than for side-on NO coordination, whereas the 2s2s σ orbital has lower intensity. XES calculations in which the Ni-N-O bond angle was fixed over the range from 80° to 176° suggest that differences in NO coordination angles of ∼10° could be experimentally distinguished. Calculations of Cu nitrite reductase (NiR) demonstrate the utility of XES for characterizing NO intermediates in metalloenzymes. This work shows the capability of XES to distinguish NO coordination modes and oxidation states at Ni and highlights applications in quantifying small molecule activation in enzymes.
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Affiliation(s)
- Phan N Phu
- Department of Chemistry & Biochemistry, California State Polytechnic University, Pomona, California 91768, United States
| | - Carlos E Gutierrez
- Department of Chemistry & Biochemistry, California State Polytechnic University, Pomona, California 91768, United States
| | - Subrata Kundu
- Department of Chemistry, Georgetown University, Box 571227, Washington, D.C. 20057, United States.,School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Kerala 695551, India
| | - Dimosthenis Sokaras
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Thomas Kroll
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Timothy H Warren
- Department of Chemistry, Georgetown University, Box 571227, Washington, D.C. 20057, United States
| | - S Chantal E Stieber
- Department of Chemistry & Biochemistry, California State Polytechnic University, Pomona, California 91768, United States
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23
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Castillo-Blas C, Romero-Muñiz I, Mavrandonakis A, Simonelli L, Platero-Prats AE. Unravelling the local structure of catalytic Fe-oxo clusters stabilized on the MOF-808 metal organic-framework. Chem Commun (Camb) 2020; 56:15615-15618. [PMID: 33290455 DOI: 10.1039/d0cc06134d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Stabilizing catalytic iron-oxo-clusters within nanoporous metal-organic frameworks (MOFs) is a powerful strategy to prepare new active materials for the degradation of toxic chemicals, such as bisphenol A. Herein, we combine pair distribution function analysis of total X-ray scattering data and X-ray absorption spectroscopy, with computational modelling to understand the local structural nature of added redox-active iron-oxo clusters bridging neighbouring zirconia-nodes within MOF-808.
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Affiliation(s)
- Celia Castillo-Blas
- Departamento de Química Inorgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, Campus de Cantoblanco, Madrid 28049, Spain.
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24
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Arnett CH, Bogacz I, Chatterjee R, Yano J, Oyala PH, Agapie T. Mixed-Valent Diiron μ-Carbyne, μ-Hydride Complexes: Implications for Nitrogenase. J Am Chem Soc 2020; 142:18795-18813. [PMID: 32976708 DOI: 10.1021/jacs.0c05920] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Binding of N2 by the FeMo-cofactor of nitrogenase is believed to occur after transfer of 4 e- and 4 H+ equivalents to the active site. Although pulse EPR studies indicate the presence of two Fe-(μ-H)-Fe moieties, the structural and electronic features of this mixed valent intermediate remain poorly understood. Toward an improved understanding of this bioorganometallic cluster, we report herein that diiron μ-carbyne complex (P6ArC)Fe2(μ-H) can be oxidized and reduced, allowing for the first time spectral characterization of two EPR-active Fe(μ-C)(μ-H)Fe model complexes linked by a 2 e- transfer which bear some resemblance to a pair of En and En+2 states of nitrogenase. Both species populate S = 1/2 states at low temperatures, and the influence of valence (de)localization on the spectroscopic signature of the μ-hydride ligand was evaluated by pulse EPR studies. Compared to analogous data for the {Fe2(μ-H)}2 state of FeMoco (E4(4H)), the data and analysis presented herein suggest that the hydride ligands in E4(4H) bridge isovalent (most probably FeIII) metal centers. Although electron transfer involves metal-localized orbitals, investigations of [(P6ArC)Fe2(μ-H)]+1 and [(P6ArC)Fe2(μ-H)]-1 by pulse EPR revealed that redox chemistry induces significant changes in Fe-C covalency (-50% upon 2 e- reduction), a conclusion further supported by X-ray absorption spectroscopy, 57Fe Mössbauer studies, and DFT calculations. Combined, our studies demonstrate that changes in covalency buffer against the accumulation of excess charge density on the metals by partially redistributing it to the bridging carbon, thereby facilitating multielectron transformations.
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Affiliation(s)
- Charles H Arnett
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Isabel Bogacz
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Ruchira Chatterjee
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Junko Yano
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Paul H Oyala
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Theodor Agapie
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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25
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Van Stappen C, Decamps L, Cutsail GE, Bjornsson R, Henthorn JT, Birrell JA, DeBeer S. The Spectroscopy of Nitrogenases. Chem Rev 2020; 120:5005-5081. [PMID: 32237739 PMCID: PMC7318057 DOI: 10.1021/acs.chemrev.9b00650] [Citation(s) in RCA: 111] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Indexed: 01/08/2023]
Abstract
Nitrogenases are responsible for biological nitrogen fixation, a crucial step in the biogeochemical nitrogen cycle. These enzymes utilize a two-component protein system and a series of iron-sulfur clusters to perform this reaction, culminating at the FeMco active site (M = Mo, V, Fe), which is capable of binding and reducing N2 to 2NH3. In this review, we summarize how different spectroscopic approaches have shed light on various aspects of these enzymes, including their structure, mechanism, alternative reactivity, and maturation. Synthetic model chemistry and theory have also played significant roles in developing our present understanding of these systems and are discussed in the context of their contributions to interpreting the nature of nitrogenases. Despite years of significant progress, there is still much to be learned from these enzymes through spectroscopic means, and we highlight where further spectroscopic investigations are needed.
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Affiliation(s)
- Casey Van Stappen
- Max Planck Institute for
Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Laure Decamps
- Max Planck Institute for
Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - George E. Cutsail
- Max Planck Institute for
Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Ragnar Bjornsson
- Max Planck Institute for
Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Justin T. Henthorn
- Max Planck Institute for
Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - James A. Birrell
- Max Planck Institute for
Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Serena DeBeer
- Max Planck Institute for
Chemical Energy Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
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26
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Neese F, Wennmohs F, Becker U, Riplinger C. The ORCA quantum chemistry program package. J Chem Phys 2020; 152:224108. [DOI: 10.1063/5.0004608] [Citation(s) in RCA: 697] [Impact Index Per Article: 174.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Frank Neese
- Max Planck Institut für Kohlenforschung, Kaiser-Wilhelm Platz 1, D-45470 Mülheim an der Ruhr, Germany
- FAccTs GmbH, Rolandstr. 67, 50677 Köln, Germany
| | - Frank Wennmohs
- Max Planck Institut für Kohlenforschung, Kaiser-Wilhelm Platz 1, D-45470 Mülheim an der Ruhr, Germany
| | - Ute Becker
- Max Planck Institut für Kohlenforschung, Kaiser-Wilhelm Platz 1, D-45470 Mülheim an der Ruhr, Germany
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27
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Hansen CJ, Zak JJ, Martinolich AJ, Ko JS, Bashian NH, Kaboudvand F, Van der Ven A, Melot BC, Nelson Weker J, See KA. Multielectron, Cation and Anion Redox in Lithium-Rich Iron Sulfide Cathodes. J Am Chem Soc 2020; 142:6737-6749. [DOI: 10.1021/jacs.0c00909] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Charles J. Hansen
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Joshua J. Zak
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Andrew J. Martinolich
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Jesse S. Ko
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Nicholas H. Bashian
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Farnaz Kaboudvand
- Materials Department, University of California, Santa Barbara, California 93106, United States
| | - Anton Van der Ven
- Materials Department, University of California, Santa Barbara, California 93106, United States
| | - Brent C. Melot
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Johanna Nelson Weker
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Kimberly A. See
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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28
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Chen WT, Hsu CW, Lee JF, Pao CW, Hsu IJ. Theoretical Analysis of Fe K-Edge XANES on Iron Pentacarbonyl. ACS OMEGA 2020; 5:4991-5000. [PMID: 32201785 PMCID: PMC7081404 DOI: 10.1021/acsomega.9b03887] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 02/21/2020] [Indexed: 05/21/2023]
Abstract
Iron pentacarbonyl (Fe(CO)5) is a versatile material that is utilized as an inhibitor of flame, shows soot suppressibility, and is used as a precursor for focused electron-beam-induced deposition (FEBID). X-ray absorption near-edge structure (XANES) of the K edge, which is a powerful technique for monitoring the oxidation states and coordination environment of metal sites, can be used to gain insight into Fe(CO)5-related reaction mechanisms in in situ experiments. We use a finite difference method (FDM) and molecular-orbital-based time-dependent density functional theory (TDDFT) calculations to clarify the Fe K-edge XANES features of Fe(CO)5. The two pre-edge peaks P1 and P2 are mainly the Fe(1s) → Fe-C(σ*) and Fe(1s) → Fe-C(π*) transitions, respectively. When the geometry transformed from D 3h to C 4v symmetry, a ∼30% decrease of the pre-edge P2 intensity was observed in the simulated spectra. This implies that the π bonding of Fe and CO is sensitive to changes in geometry. The following rising edge and white line regions are assigned to the Fe(1s) → Fe(4p)(mixing C(2p)) transitions. Our results may provide useful information to interpret XANES spectra variations of in situ reactions of metal-CO or similar compounds with π acceptor ligandlike metal-CN complexes.
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Affiliation(s)
- Wei-Ting Chen
- Department
of Molecular Science and Engineering, National
Taipei University of Technology, Taipei 10608, Taiwan
| | - Che-Wei Hsu
- Department
of Molecular Science and Engineering, National
Taipei University of Technology, Taipei 10608, Taiwan
| | - Jyh-Fu Lee
- National
Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - Chih-Wen Pao
- National
Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - I-Jui Hsu
- Department
of Molecular Science and Engineering, National
Taipei University of Technology, Taipei 10608, Taiwan
- Research
and Development Center for Smart Textile Technology, National Taipei University of Technology, Taipei 10608, Taiwan
- E-mail: .
Tel: +886-2-27712171#2420
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29
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Nagelski AL, Fataftah MS, Bollmeyer MM, McWilliams SF, MacMillan SN, Mercado BQ, Lancaster KM, Holland PL. The influences of carbon donor ligands on biomimetic multi-iron complexes for N 2 reduction. Chem Sci 2020; 11:12710-12720. [PMID: 34094466 PMCID: PMC8163302 DOI: 10.1039/d0sc03447a] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The active site clusters of nitrogenase enzymes possess the only examples of carbides in biology. These are the only biological FeS clusters that are capable of reducing N2 to NH4+, implicating the central carbon and its interaction with Fe as important in the mechanism of N2 reduction. This biological question motivates study of the influence of carbon donors on the electronic structure and reactivity of unsaturated, high-spin iron centers. Here, we present functional and structural models that test the impacts of carbon donors and sulfide donors in simpler iron compounds. We report the first example of a diiron complex that is bridged by an alkylidene and a sulfide, which serves as a high-fidelity structural and spectroscopic model of a two-iron portion of the active-site cluster (FeMoco) in the resting state of Mo-nitrogenase. The model complexes have antiferromagnetically coupled pairs of high-spin iron centers, and sulfur K-edge X-ray absorption spectroscopy shows comparable covalency of the sulfide for C and S bridged species. The sulfur-bridged compound does not interact with N2 even upon reduction, but upon removal of the sulfide it becomes capable of reducing N2 to NH4+ with the addition of protons and electrons. This provides synthetic support for sulfide extrusion in the activation of nitrogenase cofactors. High-spin diiron alkylidenes give insight into the electronic structure and functional relevance of carbon in the FeMoco active site of nitrogenase.![]()
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Affiliation(s)
| | | | - Melissa M. Bollmeyer
- Department of Chemistry and Chemical Biology
- Baker Laboratory
- Cornell University
- Ithaca
- USA
| | | | - Samantha N. MacMillan
- Department of Chemistry and Chemical Biology
- Baker Laboratory
- Cornell University
- Ithaca
- USA
| | | | - Kyle M. Lancaster
- Department of Chemistry and Chemical Biology
- Baker Laboratory
- Cornell University
- Ithaca
- USA
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30
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Aðalsteinsson HM, Lima FA, Galuppo C, Abbehausen C. Evaluation of cobalt complexes with tripod ligands for zinc finger targeting. Dalton Trans 2020; 49:16143-16153. [DOI: 10.1039/d0dt00067a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
We report the ability of CoII and CoIII complexes of tri(2-pyridylmethyl)amine and N,N-di(2-pyridylmethyl)glycinate to disrupt zinc fingers.
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Affiliation(s)
| | - Frederico A. Lima
- European X-Ray Free-Electron Laser Facility GmbH
- 22869 Schenefeld
- Germany
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31
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Oudsen JPH, Venderbosch B, Korstanje TJ, Tromp M. Electronic characterization of redox (non)-innocent Fe 2S 2 reference systems: a multi K-edge X-ray spectroscopic study. RSC Adv 2020; 10:729-738. [PMID: 35494446 PMCID: PMC9048190 DOI: 10.1039/c9ra08903a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 12/19/2019] [Indexed: 01/03/2023] Open
Abstract
Di-iron dithiolate hydrogenase model complexes are promising systems for electrocatalytic production of dihydrogen and have therefore been spectroscopically and theoretically investigated in this study. The direct effect of ligand substitution on the redox activity of the complex is examined. In order to understand and eventually optimize such systems, we characterised both metal and ligand in detail, using element specific X-ray absorption Fe- and S-K edge XAS. The (electronic) structure of three different [Fe2S2] hydrogenase systems in their non-reduced state was investigated. The effect of one- and two-electron reduction on the (electronic) structure was subsequently investigated. The S K-edge XAS spectra proved to be sensitive to delocalization of the electron density into the aromatic ring. The earlier postulated charge and spin localization in these complexes could now be measured directly using XANES. Moreover, the electron density (from S K-edge XANES) could be directly correlated to the Fe–CO bond length (from Fe K-edge EXAFS), which are in turn both related to the reported catalytic activity of these complexes. The delocalization of the electron density into the conjugated π-system of the aromatic moieties lowers the basicity of the diiron core and since protonation occurs at the diiron (as a rate determining step), lowering the basicity decreases the extent of protonation and consequently the catalytic activity. Di-iron dithiolate hydrogenase model complexes are promising systems for electrocatalytic production of dihydrogen and have therefore been spectroscopically and theoretically investigated in this study.![]()
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Affiliation(s)
- J. P. H. Oudsen
- Sustainable Materials Characterization
- Van't Hoff Institute for Molecular Sciences
- University of Amsterdam
- 1098 XH Amsterdam
- The Netherlands
| | - B. Venderbosch
- Sustainable Materials Characterization
- Van't Hoff Institute for Molecular Sciences
- University of Amsterdam
- 1098 XH Amsterdam
- The Netherlands
| | - T. J. Korstanje
- Sustainable Materials Characterization
- Van't Hoff Institute for Molecular Sciences
- University of Amsterdam
- 1098 XH Amsterdam
- The Netherlands
| | - M. Tromp
- Materials Chemistry
- Zernike Institute for Advanced Materials
- 9747AG Groningen
- The Netherlands
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32
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Bergmann TG, Welzel MO, Jacob CR. Towards theoretical spectroscopy with error bars: systematic quantification of the structural sensitivity of calculated spectra. Chem Sci 2019; 11:1862-1877. [PMID: 34123280 PMCID: PMC8148348 DOI: 10.1039/c9sc05103a] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Molecular spectra calculated with quantum-chemical methods are subject to a number of uncertainties (e.g., errors introduced by the computational methodology) that hamper the direct comparison of experiment and computation. Judging these uncertainties is crucial for drawing reliable conclusions from the interplay of experimental and theoretical spectroscopy, but largely relies on subjective judgment. Here, we explore the application of methods from uncertainty quantification to theoretical spectroscopy, with the ultimate goal of providing systematic error bars for calculated spectra. As a first target, we consider distortions of the underlying molecular structure as one important source of uncertainty. We show that by performing a principal component analysis, the most influential collective distortions can be identified, which allows for the construction of surrogate models that are amenable to a statistical analysis of the propagation of uncertainties in the molecular structure to uncertainties in the calculated spectrum. This is applied to the calculation of X-ray emission spectra of iron carbonyl complexes, of the electronic excitation spectrum of a coumarin dye, and of the infrared spectrum of alanine. We show that with our approach it becomes possible to obtain error bars for calculated spectra that account for uncertainties in the molecular structure. This is an important first step towards systematically quantifying other relevant sources of uncertainty in theoretical spectroscopy. Uncertainty quantification is applied in theoretical spectroscopy to obtain error bars accounting for the structural sensitivity of calculated spectra.![]()
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Affiliation(s)
- Tobias G Bergmann
- Technische Universität Braunschweig, Institute of Physical and Theoretical Chemistry Gaußstraße 17 38106 Braunschweig Germany
| | - Michael O Welzel
- Technische Universität Braunschweig, Institute of Physical and Theoretical Chemistry Gaußstraße 17 38106 Braunschweig Germany
| | - Christoph R Jacob
- Technische Universität Braunschweig, Institute of Physical and Theoretical Chemistry Gaußstraße 17 38106 Braunschweig Germany
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33
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McGale J, Cutsail GE, Joseph C, Rose MJ, DeBeer S. Spectroscopic X-ray and Mössbauer Characterization of M 6 and M 5 Iron(Molybdenum)-Carbonyl Carbide Clusters: High Carbide-Iron Covalency Enhances Local Iron Site Electron Density Despite Cluster Oxidation. Inorg Chem 2019; 58:12918-12932. [PMID: 31553598 PMCID: PMC6784818 DOI: 10.1021/acs.inorgchem.9b01870] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
The present study
employs a suite of spectroscopic techniques to
evaluate the electronic and bonding characteristics of the interstitial
carbide in a set of iron-carbonyl-carbide clusters, one of which is
substituted with a molybdenum atom. The M6C and M5C clusters are the dianions (Et4N)2[Fe6(μ6-C)(μ2-CO)2(CO)14] (1),
[K(benzo-18-crown-6)]2[Fe5(μ5-C)(μ2-CO)1(CO)13] (2), and [K(benzo-18-crown-6)]2[Fe5Mo(μ6-C)(μ2-CO)2(CO)15] (3). Because 1 and 2 have the same overall cluster charge (2−) but different numbers
of iron sites (1: 6 sites → 2: 5
sites), the metal atoms of 2 are formally oxidized compared
to those in 1. Despite this, Mössbauer studies
indicate that the iron sites in 2 possess significantly
greater electron density (lower spectroscopic oxidation state)
compared with those in 1. Iron K-edge X-ray absorption
and valence-to-core X-ray emission spectroscopy measurements, paired
with density functional theory spectral calculations, revealed the
presence of significant metal-to-metal and carbide 2p-based character
in the filled valence and low-lying unfilled electronic manifolds.
In all of the above experiments, the presence of the molybdenum atom
in 3 (Fe5Mo) results in somewhat unremarkable
spectroscopic properties that are essentially a “hybrid”
of 1 (Fe6) and 2 (Fe5). The overall electronic portrait that emerges illustrates that
the central inorganic carbide ligand is essential for distributing
charge and maximizing electronic communication throughout the cluster.
It is evident that the carbide coordination environment is quite flexible
and adaptive: it can drastically modify the covalency of individual
Fe–C bonds based on local structural changes and redox manipulation
of the clusters. In light of these findings, our data and calculations
suggest a potential role for the central carbon atom in FeMoco, which
likely performs a similar function in order to maintain cluster integrity
through multiple redox and ligand binding events. An in-depth
spectroscopic investigation of a series of iron-carbonyl
carbide complexes: [Fe6C] (1), [Fe5C] (2), and [Fe5CMo] (3) is
described. Using Mössbauer spectroscopy, valence-to-core X-ray
emission spectroscopy, and high-energy-resolution fluorescence-detected
X-ray absorption spectroscopy, we detail the ability of the conserved
central carbon atom in maintaining cluster stability despite dramatic
geometric rearrangements. Our study suggests a potential role for
the interstitial carbide in FeMoco as an electronic modulator, allowing
for charge and ligand accumulation under turnover conditions.
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Affiliation(s)
- Jeremy McGale
- Department of Inorganic Spectroscopy , Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36 , D-45470 , Mülheim an der Ruhr , Germany
| | - George E Cutsail
- Department of Inorganic Spectroscopy , Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36 , D-45470 , Mülheim an der Ruhr , Germany
| | - Chris Joseph
- Department of Chemistry , The University of Texas at Austin , Austin , Texas 78712 , United States
| | - Michael J Rose
- Department of Chemistry , The University of Texas at Austin , Austin , Texas 78712 , United States
| | - Serena DeBeer
- Department of Inorganic Spectroscopy , Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36 , D-45470 , Mülheim an der Ruhr , Germany
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34
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Henthorn J, Arias RJ, Koroidov S, Kroll T, Sokaras D, Bergmann U, Rees DC, DeBeer S. Localized Electronic Structure of Nitrogenase FeMoco Revealed by Selenium K-Edge High Resolution X-ray Absorption Spectroscopy. J Am Chem Soc 2019; 141:13676-13688. [PMID: 31356071 PMCID: PMC6716209 DOI: 10.1021/jacs.9b06988] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Indexed: 11/28/2022]
Abstract
The size and complexity of Mo-dependent nitrogenase, a multicomponent enzyme capable of reducing dinitrogen to ammonia, have made a detailed understanding of the FeMo cofactor (FeMoco) active site electronic structure an ongoing challenge. Selective substitution of sulfur by selenium in FeMoco affords a unique probe wherein local Fe-Se interactions can be directly interrogated via high-energy resolution fluorescence detected X-ray absorption spectroscopic (HERFD XAS) and extended X-ray absorption fine structure (EXAFS) studies. These studies reveal a significant asymmetry in the electronic distribution of the FeMoco, suggesting a more localized electronic structure picture than is typically assumed for iron-sulfur clusters. Supported by experimental small molecule model data in combination with time dependent density functional theory (TDDFT) calculations, the HERFD XAS data is consistent with an assignment of Fe2/Fe6 as an antiferromagnetically coupled diferric pair. HERFD XAS and EXAFS have also been applied to Se-substituted CO-inhibited MoFe protein, demonstrating the ability of these methods to reveal electronic and structural changes that occur upon substrate binding. These results emphasize the utility of Se HERFD XAS and EXAFS for selectively probing the local electronic and geometric structure of FeMoco.
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Affiliation(s)
- Justin
T. Henthorn
- Max
Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, D-45470 Mülheim an der
Ruhr, Germany
| | - Renee J. Arias
- Division
of Chemistry and Chemical Engineering, California
Institute of Technology, Pasadena, California 91125, United States
| | - Sergey Koroidov
- PULSE
Institute, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Thomas Kroll
- Stanford
Synchrotron Radiation Lightsource, SLAC
National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Dimosthenis Sokaras
- Stanford
Synchrotron Radiation Lightsource, SLAC
National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Uwe Bergmann
- PULSE
Institute, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Douglas C. Rees
- Division
of Chemistry and Chemical Engineering, California
Institute of Technology, Pasadena, California 91125, United States
- Howard
Hughes Medical Institute, California Institute
of Technology, Pasadena, California 91125, United States
| | - Serena DeBeer
- Max
Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, D-45470 Mülheim an der
Ruhr, Germany
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35
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Van Stappen C, Davydov R, Yang ZY, Fan R, Guo Y, Bill E, Seefeldt LC, Hoffman BM, DeBeer S. Spectroscopic Description of the E 1 State of Mo Nitrogenase Based on Mo and Fe X-ray Absorption and Mössbauer Studies. Inorg Chem 2019; 58:12365-12376. [PMID: 31441651 PMCID: PMC6751781 DOI: 10.1021/acs.inorgchem.9b01951] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Mo nitrogenase (N2ase) utilizes a two-component protein system, the catalytic MoFe and its electron-transfer partner FeP, to reduce atmospheric dinitrogen (N2) to ammonia (NH3). The FeMo cofactor contained in the MoFe protein serves as the catalytic center for this reaction and has long inspired model chemistry oriented toward activating N2. This field of chemistry has relied heavily on the detailed characterization of how Mo N2ase accomplishes this feat. Understanding the reaction mechanism of Mo N2ase itself has presented one of the most challenging problems in bioinorganic chemistry because of the ephemeral nature of its catalytic intermediates, which are difficult, if not impossible, to singly isolate. This is further exacerbated by the near necessity of FeP to reduce native MoFe, rendering most traditional means of selective reduction inept. We have now investigated the first fundamental intermediate of the MoFe catalytic cycle, E1, as prepared both by low-flux turnover and radiolytic cryoreduction, using a combination of Mo Kα high-energy-resolution fluorescence detection and Fe K-edge partial-fluorescence-yield X-ray absorption spectroscopy techniques. The results demonstrate that the formation of this state is the result of an Fe-centered reduction and that Mo remains redox-innocent. Furthermore, using Fe X-ray absorption and 57Fe Mössbauer spectroscopies, we correlate a previously reported unique species formed under cryoreducing conditions to the natively formed E1 state through annealing, demonstrating the viability of cryoreduction in studying the catalytic intermediates of MoFe.
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Affiliation(s)
- Casey Van Stappen
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36 , 45470 Mülheim an der Ruhr , Germany
| | - Roman Davydov
- Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States
| | - Zhi-Yong Yang
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
| | - Ruixi Fan
- Department of Chemistry , Carnegie Mellon University , Pittsburgh , Pennsylvania 15213 , United States
| | - Yisong Guo
- Department of Chemistry , Carnegie Mellon University , Pittsburgh , Pennsylvania 15213 , United States
| | - Eckhard Bill
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36 , 45470 Mülheim an der Ruhr , Germany
| | - Lance C Seefeldt
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
| | - Brian M Hoffman
- Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36 , 45470 Mülheim an der Ruhr , Germany
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36
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Yogendra S, Weyhermüller T, Hahn AW, DeBeer S. From Ylides to Doubly Yldiide-Bridged Iron(II) High Spin Dimers via Self-Protolysis. Inorg Chem 2019; 58:9358-9367. [PMID: 31260277 PMCID: PMC6750861 DOI: 10.1021/acs.inorgchem.9b01086] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Indexed: 12/20/2022]
Abstract
A synthetic strategy for the preparation of novel doubly yldiide bridged iron(II) high spin dimers ([(μ2-C)FeL]2, L = N(SiMe3)2, Mesityl) has been developed. This includes the synthesis of ylide-iron(II) monomers [(Ylide)FeL2] via adduct formation. Subsequent self-protolysis at elevated temperatures by in situ deprotonation of the ylide ligands results in a dimerization reaction forming the desired bridging μ2-C yldiide ligands in [(μ2-C)FeL]2. The comprehensive structural and electronic analysis of dimers [(μ2-C)FeL]2, including NMR, Mössbauer, and X-ray spectroscopy, as well as X-ray crystallography, SQUID, and DFT calculations, confirm their high-spin FeII configurations. Interestingly, the Fe2C2 cores display very acute Fe-C-Fe angles (averaged: 78.6(2)°) resulting in short Fe···Fe distances (averaged: 2.588(2) Å). A remarkably strong antiferromagnetic coupling between the Fe centers has been identified. Strongly polarized Fe-C bonds are observed where the negative charge is mostly centered at the μ2-C yldiide ligands.
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Affiliation(s)
- Sivathmeehan Yogendra
- Max Planck Institute for Chemical Energy
Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Thomas Weyhermüller
- Max Planck Institute for Chemical Energy
Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Anselm W. Hahn
- Max Planck Institute for Chemical Energy
Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy
Conversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
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37
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Kowalska JK, Henthorn JT, Van Stappen C, Trncik C, Einsle O, Keavney D, DeBeer S. X-ray Magnetic Circular Dichroism Spectroscopy Applied to Nitrogenase and Related Models: Experimental Evidence for a Spin-Coupled Molybdenum(III) Center. Angew Chem Int Ed Engl 2019; 58:9373-9377. [PMID: 31119827 PMCID: PMC6772009 DOI: 10.1002/anie.201901899] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 04/17/2019] [Indexed: 11/23/2022]
Abstract
Nitrogenase enzymes catalyze the reduction of atmospheric dinitrogen to ammonia utilizing a Mo‐7Fe‐9S‐C active site, the so‐called FeMoco cluster. FeMoco and an analogous small‐molecule (Et4N)[(Tp)MoFe3S4Cl3] cubane have both been proposed to contain unusual spin‐coupled MoIII sites with an S(Mo)=1/2 non‐Hund configuration at the Mo atom. Herein, we present Fe and Mo L3‐edge X‐ray magnetic circular dichroism (XMCD) spectroscopy of the (Et4N)[(Tp)MoFe3S4Cl3] cubane and Fe L2,3‐edge XMCD spectroscopy of the MoFe protein (containing both FeMoco and the 8Fe‐7S P‐cluster active sites). As the P‐clusters of MoFe protein have an S=0 total spin, these are effectively XMCD‐silent at low temperature and high magnetic field, allowing for FeMoco to be selectively probed by Fe L2,3‐edge XMCD within the intact MoFe protein. Further, Mo L3‐edge XMCD spectroscopy of the cubane model has provided experimental support for a local S(Mo)=1/2 configuration, demonstrating the power and selectivity of XMCD.
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Affiliation(s)
- Joanna K Kowalska
- Inorganic Spectroscopy, Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470, Mülheim an der Ruhr, Germany
| | - Justin T Henthorn
- Inorganic Spectroscopy, Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470, Mülheim an der Ruhr, Germany
| | - Casey Van Stappen
- Inorganic Spectroscopy, Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470, Mülheim an der Ruhr, Germany
| | - Christian Trncik
- Institute for Biochemistry and BIOSS Centre for Biological Signalling Studies, Albert Ludwigs University of Freiburg, Albertstrasse 21, 79104, Freiburg, Germany
| | - Oliver Einsle
- Institute for Biochemistry and BIOSS Centre for Biological Signalling Studies, Albert Ludwigs University of Freiburg, Albertstrasse 21, 79104, Freiburg, Germany
| | - David Keavney
- Argonne National Laboratory, 9700 S. Cass Ave, Argonne, IL, 60439, USA
| | - Serena DeBeer
- Inorganic Spectroscopy, Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, 45470, Mülheim an der Ruhr, Germany
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38
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Kowalska JK, Henthorn JT, Van Stappen C, Trncik C, Einsle O, Keavney D, DeBeer S. X‐ray Magnetic Circular Dichroism Spectroscopy Applied to Nitrogenase and Related Models: Experimental Evidence for a Spin‐Coupled Molybdenum(III) Center. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201901899] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Joanna K. Kowalska
- Inorganic Spectroscopy Max Planck Institute for Chemical Energy Conversion Stiftstrasse 34–36 45470 Mülheim an der Ruhr Germany
| | - Justin T. Henthorn
- Inorganic Spectroscopy Max Planck Institute for Chemical Energy Conversion Stiftstrasse 34–36 45470 Mülheim an der Ruhr Germany
| | - Casey Van Stappen
- Inorganic Spectroscopy Max Planck Institute for Chemical Energy Conversion Stiftstrasse 34–36 45470 Mülheim an der Ruhr Germany
| | - Christian Trncik
- Institute for Biochemistry and BIOSS Centre for Biological Signalling Studies Albert Ludwigs University of Freiburg Albertstrasse 21 79104 Freiburg Germany
| | - Oliver Einsle
- Institute for Biochemistry and BIOSS Centre for Biological Signalling Studies Albert Ludwigs University of Freiburg Albertstrasse 21 79104 Freiburg Germany
| | - David Keavney
- Argonne National Laboratory 9700 S. Cass Ave Argonne IL 60439 USA
| | - Serena DeBeer
- Inorganic Spectroscopy Max Planck Institute for Chemical Energy Conversion Stiftstrasse 34–36 45470 Mülheim an der Ruhr Germany
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39
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Kalläne SI, Hahn AW, Weyhermüller T, Bill E, Neese F, DeBeer S, van Gastel M. Spectroscopic and Quantum Chemical Investigation of Benzene-1,2-dithiolate-Coordinated Diiron Complexes with Relevance to Dinitrogen Activation. Inorg Chem 2019; 58:5111-5125. [DOI: 10.1021/acs.inorgchem.9b00177] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sabrina I. Kalläne
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
| | - Anselm W. Hahn
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
| | - Thomas Weyhermüller
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
| | - Eckhard Bill
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
| | - Frank Neese
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelmplatz 1, D-45470 Mülheim an der Ruhr, Germany
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
| | - Maurice van Gastel
- Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelmplatz 1, D-45470 Mülheim an der Ruhr, Germany
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40
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Wenke BB, Spatzal T, Rees DC. Site-Specific Oxidation State Assignments of the Iron Atoms in the [4Fe:4S] 2+/1+/0 States of the Nitrogenase Fe-Protein. Angew Chem Int Ed Engl 2019; 58:3894-3897. [PMID: 30698901 PMCID: PMC6519357 DOI: 10.1002/anie.201813966] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Indexed: 12/05/2022]
Abstract
The nitrogenase iron protein (Fe-protein) contains an unusual [4Fe:4S] iron-sulphur cluster that is stable in three oxidation states: 2+, 1+, and 0. Here, we use spatially resolved anomalous dispersion (SpReAD) refinement to determine oxidation assignments for the individual irons for each state. Additionally, we report the 1.13-Å resolution structure for the ADP bound Fe-protein, the highest resolution Fe-protein structure presently determined. In the dithionite-reduced [4Fe:4S]1+ state, our analysis identifies a solvent exposed, delocalized Fe2.5+ pair and a buried Fe2+ pair. We propose that ATP binding by the Fe-protein promotes an internal redox rearrangement such that the solvent-exposed Fe pair becomes reduced, thereby facilitating electron transfer to the nitrogenase molybdenum iron-protein. In the [4Fe:4S]0 and [4Fe:4S]2+ states, the SpReAD analysis supports oxidation states assignments for all irons in these clusters of Fe2+ and valence delocalized Fe2.5+ , respectively.
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Affiliation(s)
- Belinda B. Wenke
- Division of Chemistry and Chemical EngineeringCalifornia Institute of TechnologyPasadenaCA91125USA
| | - Thomas Spatzal
- Howard Hughes Medical InstituteCalifornia Institute of TechnologyPasadenaCA91125USA
- Division of Chemistry and Chemical EngineeringCalifornia Institute of TechnologyPasadenaCA91125USA
| | - Douglas C. Rees
- Howard Hughes Medical InstituteCalifornia Institute of TechnologyPasadenaCA91125USA
- Division of Chemistry and Chemical EngineeringCalifornia Institute of TechnologyPasadenaCA91125USA
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41
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Maganas D, Kowalska JK, Nooijen M, DeBeer S, Neese F. Comparison of multireference ab initio wavefunction methodologies for X-ray absorption edges: A case study on [Fe(II/III)Cl4]2–/1– molecules. J Chem Phys 2019; 150:104106. [DOI: 10.1063/1.5051613] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Affiliation(s)
- Dimitrios Maganas
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Joanna K. Kowalska
- Max-Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
| | - Marcel Nooijen
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Serena DeBeer
- Max-Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
| | - Frank Neese
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
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42
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Wenke BB, Spatzal T, Rees DC. Site‐Specific Oxidation State Assignments of the Iron Atoms in the [4Fe:4S]
2+/1+/0
States of the Nitrogenase Fe‐Protein. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201813966] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Belinda B. Wenke
- Division of Chemistry and Chemical EngineeringCalifornia Institute of Technology Pasadena CA 91125 USA
| | - Thomas Spatzal
- Howard Hughes Medical InstituteCalifornia Institute of Technology Pasadena CA 91125 USA
- Division of Chemistry and Chemical EngineeringCalifornia Institute of Technology Pasadena CA 91125 USA
| | - Douglas C. Rees
- Howard Hughes Medical InstituteCalifornia Institute of Technology Pasadena CA 91125 USA
- Division of Chemistry and Chemical EngineeringCalifornia Institute of Technology Pasadena CA 91125 USA
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43
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Ohki Y, Uchida K, Hara R, Kachi M, Fujisawa M, Tada M, Sakai Y, Sameera WMC. Cubane-Type [Mo 3 S 4 M] Clusters with First-Row Groups 4-10 Transition-Metal Halides Supported by C 5 Me 5 Ligands on Molybdenum. Chemistry 2018; 24:17138-17147. [PMID: 30204282 DOI: 10.1002/chem.201804083] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Indexed: 02/02/2023]
Abstract
A synthetic protocol was developed for a series of cubane-type [Mo3 S4 M] clusters that incorporate halides of first-row transition metals (M) from Groups 4-10. This protocol is based on the anionic cluster platform [Cp*3 Mo3 S4 ]- ([1]- ; Cp*=η5 -C5 Me5 ), which crystallizes when K(18-crown-6) is used as the counter cation. Treatment of in situ-generated [1]- with such transition-metal halides led to the formation of [Mo3 S4 M] clusters, in which the M/halide ratio gradually changes from 1:2 to 1:1.5 and to 1:1, when moving from early to late transition metals. This trend suggests a tendency for early transition metals to tolerate higher oxidation states and adopt larger ionic radii relative to late transition metals. The properties of the [Mo3 S4 Fe] cluster 6 a were investigated in detail by using 57 Fe Mössbauer spectroscopy and computational methods.
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Affiliation(s)
- Yasuhiro Ohki
- Department of Chemistry, Graduate School of Science and Research Center for Materials Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602, Japan
| | - Keisuke Uchida
- Department of Chemistry, Graduate School of Science and Research Center for Materials Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602, Japan
| | - Ryota Hara
- Department of Chemistry, Graduate School of Science and Research Center for Materials Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602, Japan
| | - Mami Kachi
- Department of Chemistry, Graduate School of Science and Research Center for Materials Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602, Japan
| | - Mayu Fujisawa
- Department of Chemistry, Graduate School of Science and Research Center for Materials Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602, Japan
| | - Mizuki Tada
- Department of Chemistry, Graduate School of Science and Research Center for Materials Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602, Japan.,Research Center for Materials Science (RCMS) & Integrated Research Consortium on Chemical Sciences (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602, Japan
| | - Yoichi Sakai
- Department of Chemistry, Daido University, Takiharu-cho, Minami-ku, Nagoya, 457-8530, Japan
| | - W M C Sameera
- Institute of Low Temperature Science, Hokkaido University, Sapporo, 060-0819, Japan
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44
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Kubas A, Maszota P. Theoretical Insights into the Unique Ligation of [Fe
4
S
4
] Iron–Sulfur Clusters. Eur J Inorg Chem 2018. [DOI: 10.1002/ejic.201800165] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Adam Kubas
- Institute of Physical Chemistry Polish Academy of Sciences Kasprzaka 44/52 01‐224 Warsaw Poland
| | - Paweł Maszota
- Institute of Physical Chemistry Polish Academy of Sciences Kasprzaka 44/52 01‐224 Warsaw Poland
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45
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Van Kuiken BE, Hahn AW, Nayyar B, Schiewer CE, Lee SC, Meyer F, Weyhermüller T, Nicolaou A, Cui YT, Miyawaki J, Harada Y, DeBeer S. Electronic Spectra of Iron–Sulfur Complexes Measured by 2p3d RIXS Spectroscopy. Inorg Chem 2018; 57:7355-7361. [DOI: 10.1021/acs.inorgchem.8b01010] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Benjamin E. Van Kuiken
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Anselm W. Hahn
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Brahamjot Nayyar
- Department of Chemistry, University of Waterloo, Waterloo N2L 3G1, Canada
| | - Christine E. Schiewer
- Institute of Inorganic Chemistry, University of Göttingen, Tammannstr. 4, D-37077 Göttingen, Germany
| | - Sonny C. Lee
- Department of Chemistry, University of Waterloo, Waterloo N2L 3G1, Canada
| | - Franc Meyer
- Institute of Inorganic Chemistry, University of Göttingen, Tammannstr. 4, D-37077 Göttingen, Germany
| | - Thomas Weyhermüller
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | | | - Yi-Tao Cui
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Jun Miyawaki
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Yoshihisa Harada
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
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46
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Leipzig BK, Rees JA, Kowalska JK, Theisen RM, Kavčič M, Poon PCY, Kaminsky W, DeBeer S, Bill E, Kovacs JA. How Do Ring Size and π-Donating Thiolate Ligands Affect Redox-Active, α-Imino-N-heterocycle Ligand Activation? Inorg Chem 2018; 57:1935-1949. [PMID: 29411979 DOI: 10.1021/acs.inorgchem.7b02748] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Considerable effort has been devoted to the development of first-row transition-metal catalysts containing redox-active imino-pyridine ligands that are capable of storing multiple reducing equivalents. This property allows abundant and inexpensive first-row transition metals, which favor sequential one-electron redox processes, to function as competent catalysts in the concerted two-electron reduction of substrates. Herein we report the syntheses and characterization of a series of iron complexes that contain both π-donating thiolate and π-accepting (α-imino)-N-heterocycle redox-active ligands, with progressively larger N-heterocycle rings (imidazole, pyridine, and quinoline). A cooperative interaction between these complementary redox-active ligands is shown to dictate the properties of these complexes. Unusually intense charge-transfer (CT) bands, and intraligand metrical parameters, reminiscent of a reduced (α-imino)-N-heterocycle ligand (L•-), initially suggested that the electron-donating thiolate had reduced the N-heterocycle. Sulfur K-edge X-ray absorption spectroscopic (XAS) data, however, provides evidence for direct communication, via backbonding, between the thiolate sulfur and the formally orthogonal (α-imino)-N-heterocycle ligand π*-orbitals. DFT calculations provide evidence for extensive delocalization of bonds over the sulfur, iron, and (α-imino)-N-heterocycle, and TD-DFT shows that the intense optical CT bands involve transitions between a mixed Fe/S donor, and (α-imino)-N-heterocycle π*-acceptor orbital. The energies and intensities of the optical and S K-edge pre-edge XAS transitions are shown to correlate with N-heterocycle ring size, as do the redox potentials. When the thiolate is replaced with a thioether, or when the low-spin S = 0 Fe(II) is replaced with a high-spin S = 3/2 Co(II), the N-heterocycle ligand metrical parameters and electronic structure do not change relative to the neutral L0 ligand. With respect to the development of future catalysts containing redox-active ligands, the energy cost of storing reducing equivalents is shown to be lowest when a quinoline, as opposed to imidazole or pyridine, is incorporated into the ligand backbone of the corresponding Fe complex.
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Affiliation(s)
- Benjamin K Leipzig
- The Department of Chemistry, University of Washington , Box 351700, Seattle, Washington 98195-1700, United States
| | - Julian A Rees
- The Department of Chemistry, University of Washington , Box 351700, Seattle, Washington 98195-1700, United States
| | - Joanna K Kowalska
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
| | - Roslyn M Theisen
- The Department of Chemistry, University of Washington , Box 351700, Seattle, Washington 98195-1700, United States
| | | | | | - Werner Kaminsky
- The Department of Chemistry, University of Washington , Box 351700, Seattle, Washington 98195-1700, United States
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
| | - Eckhard Bill
- Max Planck Institute for Chemical Energy Conversion , Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
| | - Julie A Kovacs
- The Department of Chemistry, University of Washington , Box 351700, Seattle, Washington 98195-1700, United States
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47
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Maganas D, DeBeer S, Neese F. Pair Natural Orbital Restricted Open-Shell Configuration Interaction (PNO-ROCIS) Approach for Calculating X-ray Absorption Spectra of Large Chemical Systems. J Phys Chem A 2018; 122:1215-1227. [DOI: 10.1021/acs.jpca.7b10880] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Dimitrios Maganas
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Frank Neese
- Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
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48
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Abbehausen C, de Paiva REF, Bjornsson R, Gomes SQ, Du Z, Corbi PP, Lima FA, Farrell N. X-ray Absorption Spectroscopy Combined with Time-Dependent Density Functional Theory Elucidates Differential Substitution Pathways of Au(I) and Au(III) with Zinc Fingers. Inorg Chem 2017; 57:218-230. [DOI: 10.1021/acs.inorgchem.7b02406] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Camilla Abbehausen
- Institute of Chemistry, University of Campinas—UNICAMP, P.O. Box 6154, CEP, 13083-970 Campinas, São Paulo, Brazil
| | | | - Ragnar Bjornsson
- Science Institute, University of Iceland, Dunhagi 3,
IS-107 Reykjavik, Iceland
| | - Saulo Quintana Gomes
- Institute of Chemistry, University of Campinas—UNICAMP, P.O. Box 6154, CEP, 13083-970 Campinas, São Paulo, Brazil
| | - Zhifeng Du
- Department of Chemistry, Virginia Commonwealth University, 1001 W. Main Street, Richmond, Virginia 23284-2006, United States
| | - Pedro Paulo Corbi
- Institute of Chemistry, University of Campinas—UNICAMP, P.O. Box 6154, CEP, 13083-970 Campinas, São Paulo, Brazil
| | - Frederico Alves Lima
- Centro Nacional de Pesquisa em Energia
e Materiais, Brazilian Synchrotron Light Laboratory—LNLS, CP 6192, 13084-971 Campinas, São Paulo, Brazil
| | - Nicholas Farrell
- Department of Chemistry, Virginia Commonwealth University, 1001 W. Main Street, Richmond, Virginia 23284-2006, United States
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49
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DeBeer S. Advanced X-ray Spectroscopic Methods for Studying Iron-Sulfur-Containing Proteins and Model Complexes. Methods Enzymol 2017; 599:427-450. [PMID: 29746249 DOI: 10.1016/bs.mie.2017.09.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
In this chapter, a brief overview of X-ray spectroscopic methods that may be utilized to obtain insight into the geometric and electronic structure of iron-sulfur proteins is provided. These methods include conventional methods, such as metal and ligand K-edge X-ray absorption, as well as more advanced methods including nonresonant and resonant X-ray emission. In each section, the basic information content of the spectra is highlighted and important experimental considerations are discussed. Throughout the chapter, recent applications to iron-sulfur-containing models and proteins are highlighted.
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Affiliation(s)
- Serena DeBeer
- Max Planck Institute for Chemical Energy Conversion, Mülheim an der Ruhr, Germany.
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50
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Benediktsson B, Bjornsson R. QM/MM Study of the Nitrogenase MoFe Protein Resting State: Broken-Symmetry States, Protonation States, and QM Region Convergence in the FeMoco Active Site. Inorg Chem 2017; 56:13417-13429. [DOI: 10.1021/acs.inorgchem.7b02158] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Bardi Benediktsson
- Science Institute, University of Iceland, Dunhagi 3, 107 Reykjavik, Iceland
| | - Ragnar Bjornsson
- Science Institute, University of Iceland, Dunhagi 3, 107 Reykjavik, Iceland
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