1
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Deng Y, Wang JX, Ghosh B, Lu Y. Enzymatic CO 2 reduction catalyzed by natural and artificial Metalloenzymes. J Inorg Biochem 2024; 259:112669. [PMID: 39059175 DOI: 10.1016/j.jinorgbio.2024.112669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2024] [Revised: 07/04/2024] [Accepted: 07/17/2024] [Indexed: 07/28/2024]
Abstract
The continuously increasing level of atmospheric CO2 in the atmosphere has led to global warming. Converting CO2 into other carbon compounds could mitigate its atmospheric levels and produce valuable products, as CO2 also serves as a plentiful and inexpensive carbon feedstock. However, the inert nature of CO2 poses a major challenge for its reduction. To meet the challenge, nature has evolved metalloenzymes using transition metal ions like Fe, Ni, Mo, and W, as well as electron-transfer partners for their functions. Mimicking these enzymes, artificial metalloenzymes (ArMs) have been designed using alternative protein scaffolds and various metallocofactors like Ni, Co, Re, Rh, and FeS clusters. Both the catalytic efficiency and the scope of CO2-reduction product of these ArMs have been improved over the past decade. This review first focuses on the natural metalloenzymes that directly reduce CO2 by discussing their structures and active sites, as well as the proposed reaction mechanisms. It then introduces the common strategies for electrochemical, photochemical, or photoelectrochemical utilization of these native enzymes for CO2 reduction and highlights the most recent advancements from the past five years. We also summarize principles of protein design for bio-inspired ArMs, comparing them with native enzymatic systems and outlining challenges and opportunities in enzymatic CO2 reduction.
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Affiliation(s)
- Yunling Deng
- Department of Chemistry, The University of Texas at Austin, Austin, TX 78712, United States of America
| | - Jing-Xiang Wang
- Department of Chemistry, The University of Texas at Austin, Austin, TX 78712, United States of America
| | - Barshali Ghosh
- Department of Chemistry, The University of Texas at Austin, Austin, TX 78712, United States of America
| | - Yi Lu
- Department of Chemistry, The University of Texas at Austin, Austin, TX 78712, United States of America.
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2
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Maslać N, Cadoux C, Bolte P, Murken F, Gu W, Milton RD, Wagner T. Structural comparison of (hyper-)thermophilic nitrogenase reductases from three marine Methanococcales. FEBS J 2024; 291:3454-3480. [PMID: 38696373 DOI: 10.1111/febs.17148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 01/17/2024] [Accepted: 04/17/2024] [Indexed: 05/04/2024]
Abstract
The nitrogenase reductase NifH catalyses ATP-dependent electron delivery to the Mo-nitrogenase, a reaction central to biological dinitrogen (N2) fixation. While NifHs have been extensively studied in bacteria, structural information about their archaeal counterparts is limited. Archaeal NifHs are considered more ancient, particularly those from Methanococcales, a group of marine hydrogenotrophic methanogens, which includes diazotrophs growing at temperatures near 92 °C. Here, we structurally and biochemically analyse NifHs from three Methanococcales, offering the X-ray crystal structures from meso-, thermo-, and hyperthermophilic methanogens. While NifH from Methanococcus maripaludis (37 °C) was obtained through heterologous recombinant expression, the proteins from Methanothermococcus thermolithotrophicus (65 °C) and Methanocaldococcus infernus (85 °C) were natively purified from the diazotrophic archaea. The structures from M. thermolithotrophicus crystallised as isolated exhibit high flexibility. In contrast, the complexes of NifH with MgADP obtained from the three methanogens are superposable, more rigid, and present remarkable structural conservation with their homologues. They retain key structural features of P-loop NTPases and share similar electrostatic profiles with the counterpart from the bacterial model organism Azotobacter vinelandii. In comparison to the NifH from the phylogenetically distant Methanosarcina acetivorans, these reductases do not cross-react significantly with Mo-nitrogenase from A. vinelandii. However, they associate with bacterial nitrogenase when ADP·AlF 4 - is added to mimic a transient reactive state. Accordingly, detailed surface analyses suggest that subtle substitutions would affect optimal binding during the catalytic cycle between the NifH from Methanococcales and the bacterial nitrogenase, implying differences in the N2-machinery from these ancient archaea.
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Affiliation(s)
- Nevena Maslać
- Microbial Metabolism Research Group, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Cécile Cadoux
- Department of Inorganic and Analytical Chemistry, Faculty of Sciences, University of Geneva, Switzerland
- National Centre of Competence in Research (NCCR) Catalysis, University of Geneva, Switzerland
| | - Pauline Bolte
- Microbial Metabolism Research Group, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Fenja Murken
- Microbial Metabolism Research Group, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Wenyu Gu
- Laboratory of Microbial Physiology and Resource Biorecovery, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédéral de Lausanne, Switzerland
| | - Ross D Milton
- Department of Inorganic and Analytical Chemistry, Faculty of Sciences, University of Geneva, Switzerland
- National Centre of Competence in Research (NCCR) Catalysis, University of Geneva, Switzerland
| | - Tristan Wagner
- Microbial Metabolism Research Group, Max Planck Institute for Marine Microbiology, Bremen, Germany
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3
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Cai HX, Wang J, Guo YR, Pan QJ. Weak Bimetal Coupling-Assisted MN 4 Catalyst for Enhanced Carbon Dioxide Reduction Reaction. Inorg Chem 2024; 63:6734-6742. [PMID: 38570330 DOI: 10.1021/acs.inorgchem.4c00058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2024]
Abstract
The design of multimetal catalysts holds immense significance for efficient CO2 capture and its conversion into economically valuable chemicals. Herein, heterobimetallic catalysts (MiMo)L were exploited for the CO2 reduction reactions (CO2RR) using relativistic density functional theory (DFT). The octadentate Pacman-like polypyrrolic ligand (H4L) accommodates two metal ions (Mo, W, Nd, and U) inside (Mi) and outside (Mo) its month, rendering a weak bimetal coupling-assisted MN4 catalytically active site. Adsorption reactions have access to energetically stable coordination modes of -OCO, -OOC, and -(OCO)2, where the donor atom(s) are marked in bold. Among all of the species, (UiMoo)L releases the most energy. Along CO2RR, it favors to produce CO. The high-efficiency CO2 reduction is attributed to the size matching of U with the ligand mouth and the effective manipulation of the electron density of both ligand and bimetals. The mechanism in which heterobimetals synergetically capture and reduce CO2 has been postulated. This establishes a reference in elaborating on the complicated heterogeneous catalysis.
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Affiliation(s)
- Hong-Xue Cai
- Key Laboratory of Functional Inorganic Material Chemistry (Ministry of Education), School of Chemistry and Materials Science, Heilongjiang University, Harbin 150080, China
| | - Juan Wang
- Key Laboratory of Functional Inorganic Material Chemistry (Ministry of Education), School of Chemistry and Materials Science, Heilongjiang University, Harbin 150080, China
| | - Yuan-Ru Guo
- Key Laboratory of Bio-based Material Science & Technology (Ministry of Education), College of Material Science and Engineering, Northeast Forestry University, Harbin 150040, China
| | - Qing-Jiang Pan
- Key Laboratory of Functional Inorganic Material Chemistry (Ministry of Education), School of Chemistry and Materials Science, Heilongjiang University, Harbin 150080, China
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4
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Schulz-Mirbach H, Dronsella B, He H, Erb TJ. Creating new-to-nature carbon fixation: A guide. Metab Eng 2024; 82:12-28. [PMID: 38160747 DOI: 10.1016/j.ymben.2023.12.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 12/23/2023] [Accepted: 12/27/2023] [Indexed: 01/03/2024]
Abstract
Synthetic biology aims at designing new biological functions from first principles. These new designs allow to expand the natural solution space and overcome the limitations of naturally evolved systems. One example is synthetic CO2-fixation pathways that promise to provide more efficient ways for the capture and conversion of CO2 than natural pathways, such as the Calvin Benson Bassham (CBB) cycle of photosynthesis. In this review, we provide a practical guideline for the design and realization of such new-to-nature CO2-fixation pathways. We introduce the concept of "synthetic CO2-fixation", and give a general overview over the enzymology and topology of synthetic pathways, before we derive general principles for their design from their eight naturally evolved analogs. We provide a comprehensive summary of synthetic carbon-assimilation pathways and derive a step-by-step, practical guide from the theoretical design to their practical implementation, before ending with an outlook on new developments in the field.
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Affiliation(s)
- Helena Schulz-Mirbach
- Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Str. 10, 35043, Marburg, Germany
| | - Beau Dronsella
- Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Str. 10, 35043, Marburg, Germany; Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam, Germany
| | - Hai He
- Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Str. 10, 35043, Marburg, Germany
| | - Tobias J Erb
- Max Planck Institute for Terrestrial Microbiology, Karl-von-Frisch-Str. 10, 35043, Marburg, Germany; Center for Synthetic Microbiology (SYNMIKRO), Karl-von-Frisch-Str. 16, D-35043, Marburg, Germany.
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5
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Solomon JB, Liu YA, Górecki K, Quechol R, Lee CC, Jasniewski AJ, Hu Y, Ribbe MW. Heterologous expression of a fully active Azotobacter vinelandii nitrogenase Fe protein in Escherichia coli. mBio 2023; 14:e0257223. [PMID: 37909748 PMCID: PMC10746259 DOI: 10.1128/mbio.02572-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 09/27/2023] [Indexed: 11/03/2023] Open
Abstract
IMPORTANCE The heterologous expression of a fully active Azotobacter vinelandii Fe protein (AvNifH) has never been accomplished. Given the functional importance of this protein in nitrogenase catalysis and assembly, the successful expression of AvNifH in Escherichia coli as reported herein supplies a key element for the further development of heterologous expression systems that explore the catalytic versatility of the Fe protein, either on its own or as a key component of nitrogenase, for nitrogenase-based biotechnological applications in the future. Moreover, the "clean" genetic background of the heterologous expression host allows for an unambiguous assessment of the effect of certain nif-encoded protein factors, such as AvNifM described in this work, in the maturation of AvNifH, highlighting the utility of this heterologous expression system in further advancing our understanding of the complex biosynthetic mechanism of nitrogenase.
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Affiliation(s)
- Joseph B. Solomon
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California, USA
- Department of Chemistry, University of California, Irvine, California, USA
| | - Yiling A. Liu
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California, USA
| | - Kamil Górecki
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California, USA
| | - Robert Quechol
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California, USA
| | - Chi Chung Lee
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California, USA
| | - Andrew J. Jasniewski
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California, USA
| | - Yilin Hu
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California, USA
| | - Markus W. Ribbe
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California, USA
- Department of Chemistry, University of California, Irvine, California, USA
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Abstract
The Fischer-Tropsch (FT) process converts a mixture of CO and H2 into liquid hydrocarbons as a major component of the gas-to-liquid technology for the production of synthetic fuels. Contrary to the energy-demanding chemical FT process, the enzymatic FT-type reactions catalyzed by nitrogenase enzymes, their metalloclusters, and synthetic mimics utilize H+ and e- as the reducing equivalents to reduce CO, CO2, and CN- into hydrocarbons under ambient conditions. The C1 chemistry exemplified by these FT-type reactions is underscored by the structural and electronic properties of the nitrogenase-associated metallocenters, and recent studies have pointed to the potential relevance of this reactivity to nitrogenase mechanism, prebiotic chemistry, and biotechnological applications. This review will provide an overview of the features of nitrogenase enzymes and associated metalloclusters, followed by a detailed discussion of the activities of various nitrogenase-derived FT systems and plausible mechanisms of the enzymatic FT reactions, highlighting the versatility of this unique reactivity while providing perspectives onto its mechanistic, evolutionary, and biotechnological implications.
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Affiliation(s)
- Yilin Hu
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine 92697-3900, USA
| | - Chi Chung Lee
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine 92697-3900, USA
| | - Mario Grosch
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine 92697-3900, USA
| | - Joseph B. Solomon
- Department of Chemistry, University of California, Irvine, CA 92697-2025, USA
| | - Wolfgang Weigand
- Institute of Inorganic and Analytical Chemistry, Friedrich Schiller University Jena, 07743 Jena, Germany
| | - Markus W. Ribbe
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine 92697-3900, USA
- Department of Chemistry, University of California, Irvine, CA 92697-2025, USA
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7
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Deng Y, Dwaraknath S, Ouyang WO, Matsumoto CJ, Ouchida S, Lu Y. Engineering an Oxygen-Binding Protein for Photocatalytic CO 2 Reductions in Water. Angew Chem Int Ed Engl 2023; 62:e202215719. [PMID: 36916067 PMCID: PMC10946749 DOI: 10.1002/anie.202215719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 03/10/2023] [Accepted: 03/10/2023] [Indexed: 03/16/2023]
Abstract
While native CO2 -reducing enzymes display remarkable catalytic efficiency and product selectivity, few artificial biocatalysts have been engineered to allow understanding how the native enzymes work. To address this issue, we report cobalt porphyrin substituted myoglobin (CoMb) as a homogeneous catalyst for photo-driven CO2 to CO conversion in water. The activity and product selectivity were optimized by varying pH and concentrations of the enzyme and the photosensitizer. Up to 2000 TON(CO) was attained at low enzyme concentrations with low product selectivity (15 %), while a product selectivity of 74 % was reached by increasing the enzyme loading but with a compromised TON(CO). The efficiency of CO generation and overall TON(CO) were further improved by introducing positively charged residues (Lys or Arg) near the active stie of CoMb, which demonstrates the value of tuning the enzyme secondary coordination sphere to enhance the CO2 -reducing performance of a protein-based photocatalytic system.
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Affiliation(s)
- Yunling Deng
- Department of ChemistryUniversity of Texas at AustinAustinTX 78712USA
| | - Sudharsan Dwaraknath
- Department of ChemistryUniversity of Illinois at Urbana-ChampaignUrbanaIL 61801USA
| | - Wenhao O. Ouyang
- Department of ChemistryUniversity of Illinois at Urbana-ChampaignUrbanaIL 61801USA
| | - Cory J. Matsumoto
- Department of ChemistryUniversity of Illinois at Urbana-ChampaignUrbanaIL 61801USA
| | - Stephanie Ouchida
- Department of ChemistryUniversity of Illinois at Urbana-ChampaignUrbanaIL 61801USA
| | - Yi Lu
- Department of ChemistryUniversity of Texas at AustinAustinTX 78712USA
- Department of ChemistryUniversity of Illinois at Urbana-ChampaignUrbanaIL 61801USA
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8
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Activation of unsaturated small molecules by bio-relevant multinuclear metal-sulfur clusters. Coord Chem Rev 2023. [DOI: 10.1016/j.ccr.2022.214838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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9
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Ribbe MW, Górecki K, Grosch M, Solomon JB, Quechol R, Liu YA, Lee CC, Hu Y. Nitrogenase Fe Protein: A Multi-Tasking Player in Substrate Reduction and Metallocluster Assembly. Molecules 2022; 27:molecules27196743. [PMID: 36235278 PMCID: PMC9571451 DOI: 10.3390/molecules27196743] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/05/2022] [Accepted: 10/06/2022] [Indexed: 11/18/2022] Open
Abstract
The Fe protein of nitrogenase plays multiple roles in substrate reduction and metallocluster assembly. Best known for its function to transfer electrons to its catalytic partner during nitrogenase catalysis, the Fe protein is also a key player in the biosynthesis of the complex metalloclusters of nitrogenase. In addition, it can function as a reductase on its own and affect the ambient reduction of CO2 or CO to hydrocarbons. This review will provide an overview of the properties and functions of the Fe protein, highlighting the relevance of this unique FeS enzyme to areas related to the catalysis, biosynthesis, and applications of the fascinating nitrogenase system.
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Affiliation(s)
- Markus W. Ribbe
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697-3900, USA
- Department of Chemistry, University of California, Irvine, CA 92697-2025, USA
- Correspondence: (M.W.R.); (Y.H.)
| | - Kamil Górecki
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697-3900, USA
| | - Mario Grosch
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697-3900, USA
| | - Joseph B. Solomon
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697-3900, USA
- Department of Chemistry, University of California, Irvine, CA 92697-2025, USA
| | - Robert Quechol
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697-3900, USA
| | - Yiling A. Liu
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697-3900, USA
| | - Chi Chung Lee
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697-3900, USA
| | - Yilin Hu
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697-3900, USA
- Correspondence: (M.W.R.); (Y.H.)
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10
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Basak Y, Jeoung JH, Domnik L, Ruickoldt J, Dobbek H. Substrate Activation at the Ni,Fe Cluster of CO Dehydrogenases: The Influence of the Protein Matrix. ACS Catal 2022. [DOI: 10.1021/acscatal.2c02922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yudhajeet Basak
- Institute of Biology, Humboldt-Universität zu Berlin, Unter den Linden 6, Berlin 10099, Germany
| | - Jae-Hun Jeoung
- Institute of Biology, Humboldt-Universität zu Berlin, Unter den Linden 6, Berlin 10099, Germany
| | - Lilith Domnik
- Institute of Biology, Humboldt-Universität zu Berlin, Unter den Linden 6, Berlin 10099, Germany
| | - Jakob Ruickoldt
- Institute of Biology, Humboldt-Universität zu Berlin, Unter den Linden 6, Berlin 10099, Germany
| | - Holger Dobbek
- Institute of Biology, Humboldt-Universität zu Berlin, Unter den Linden 6, Berlin 10099, Germany
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11
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Tanifuji K, Ohki Y, Seino H. Metal-Sulfur Clusters with Relevance to Organometallic Chemistry for Small Molecule Activation and Transformation. J SYN ORG CHEM JPN 2022. [DOI: 10.5059/yukigoseikyokaishi.80.854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
| | | | - Hidetake Seino
- Faculty of Education and Human Studies, Akita University
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12
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Buscagan TM, Kaiser JT, Rees DC. Selenocyanate derived Se-incorporation into the Nitrogenase Fe protein cluster. eLife 2022; 11:79311. [PMID: 35904245 PMCID: PMC9462850 DOI: 10.7554/elife.79311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 07/28/2022] [Indexed: 11/15/2022] Open
Abstract
The nitrogenase Fe protein mediates ATP-dependent electron transfer to the nitrogenase MoFe protein during nitrogen fixation, in addition to catalyzing MoFe protein-independent substrate (CO2) reduction and facilitating MoFe protein metallocluster biosynthesis. The precise role(s) of the Fe protein Fe4S4 cluster in some of these processes remains ill-defined. Herein, we report crystallographic data demonstrating ATP-dependent chalcogenide exchange at the Fe4S4 cluster of the nitrogenase Fe protein when potassium selenocyanate is used as the selenium source, an unexpected result as the Fe protein cluster is not traditionally perceived as a site of substrate binding within nitrogenase. The observed chalcogenide exchange illustrates that this Fe4S4 cluster is capable of core substitution reactions under certain conditions, adding to the Fe protein’s repertoire of unique properties. Many of the molecules that form the building blocks of life contain nitrogen. This element makes up most of the gas in the atmosphere, but in this form, it does not easily react, and most organisms cannot incorporate atmospheric nitrogen into biological molecules. To get around this problem, some species of bacteria produce an enzyme complex called nitrogenase that can transform nitrogen from the air into ammonia. This process is called nitrogen fixation, and it converts nitrogen into a form that can be used to sustain life. The nitrogenase complex is made up of two proteins: the MoFe protein, which contains the active site that binds nitrogen, turning it into ammonia; and the Fe protein, which drives the reaction. Besides the nitrogen fixation reaction, the Fe protein is involved in other biological processes, but it was not thought to bind directly to nitrogen, or to any of the other small molecules that the nitrogenase complex acts on. The Fe protein contains a cluster of iron and sulfur ions that is required to drive the nitrogen fixation reaction, but the role of this cluster in the other reactions performed by the Fe protein remains unclear. To better understand the role of this iron sulfur cluster, Buscagan, Kaiser and Rees used X-ray crystallography, a technique that can determine the structure of molecules. This approach revealed for the first time that when nitrogenase reacts with a small molecule called selenocyanate, the selenium in this molecule can replace the sulfur ions of the iron sulfur cluster in the Fe protein. Buscagan, Kaiser and Rees also demonstrated that the Fe protein could still incorporate selenium ions in the absence of the MoFe protein, which has traditionally been thought to provide the site essential for transforming small molecules. These results indicate that the iron sulfur cluster in the Fe protein may bind directly to small molecules that react with nitrogenase. In the future, these findings could lead to the development of new molecules that artificially produce ammonia from nitrogen, an important process for fertilizer manufacturing. In addition, the iron sulfur cluster found in the Fe protein is also present in many other proteins, so Buscagan, Kaiser and Rees’ experiments may shed light on the factors that control other biological reactions.
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Affiliation(s)
- Trixia M Buscagan
- Division of Chemistry and Chemical Engineering, Howard Hughes Medical Institute, California Institute of Technology, Pasadena, United States
| | - Jens T Kaiser
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, United States
| | - Douglas C Rees
- Division of Chemistry and Chemical Engineering, Howard Hughes Medical Institute, California Institute of Technology, Pasadena, United States
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13
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Solomon JB, Tanifuji K, Lee CC, Jasniewski AJ, Hedman B, Hodgson KO, Hu Y, Ribbe MW. Characterization of a Nitrogenase Iron Protein Substituted with a Synthetic [Fe 4 Se 4 ] Cluster. Angew Chem Int Ed Engl 2022; 61:e202202271. [PMID: 35218104 PMCID: PMC9038695 DOI: 10.1002/anie.202202271] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Indexed: 11/08/2022]
Abstract
The Fe protein of nitrogenase plays multiple roles in substrate reduction and cluster maturation via its redox-active [Fe4 S4 ] cluster. Here we report the synthesis and characterization of a water-soluble [Fe4 Se4 ] cluster that is used to substitute the [Fe4 S4 ] cluster of the Azotobacter vinelandii Fe protein (AvNifH). Biochemical, EPR and XAS/EXAFS analyses demonstrate the ability of the [Fe4 Se4 ] cluster to adopt the super-reduced, all-ferrous state upon its incorporation into AvNifH. Moreover, these studies reveal that the [Fe4 Se4 ] cluster in AvNifH already assumes a partial all-ferrous state ([Fe4 Se4 ]0 ) in the presence of dithionite, where its [Fe4 S4 ] counterpart in AvNifH exists solely in the reduced state ([Fe4 S4 ]1+ ). Such a discrepancy in the redox properties of the AvNifH-associated [Fe4 Se4 ] and [Fe4 S4 ] clusters can be used to distinguish the differential redox requirements for the substrate reduction and cluster maturation of nitrogenase, pointing to the utility of chalcogen-substituted FeS clusters in future mechanistic studies of nitrogenase catalysis and assembly.
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Affiliation(s)
- Joseph B Solomon
- Department of Molecular Biology and Biochemistry, University of Califronia, Irvine, Irvine, CA 92697-3900, USA
- Department of Chemistry, University of California, Irvine, Irvine, CA 92697-2025, USA
| | - Kazuki Tanifuji
- Department of Molecular Biology and Biochemistry, University of Califronia, Irvine, Irvine, CA 92697-3900, USA
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan
| | - Chi Chung Lee
- Department of Molecular Biology and Biochemistry, University of Califronia, Irvine, Irvine, CA 92697-3900, USA
| | - Andrew J Jasniewski
- Department of Molecular Biology and Biochemistry, University of Califronia, Irvine, Irvine, CA 92697-3900, USA
| | - Britt Hedman
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, CA 94025, USA
| | - Keith O Hodgson
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, CA 94025, USA
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Yilin Hu
- Department of Molecular Biology and Biochemistry, University of Califronia, Irvine, Irvine, CA 92697-3900, USA
| | - Markus W Ribbe
- Department of Molecular Biology and Biochemistry, University of Califronia, Irvine, Irvine, CA 92697-3900, USA
- Department of Chemistry, University of California, Irvine, Irvine, CA 92697-2025, USA
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14
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Oehlmann NN, Rebelein JG. The Conversion of Carbon Monoxide and Carbon Dioxide by Nitrogenases. Chembiochem 2022; 23:e202100453. [PMID: 34643977 PMCID: PMC9298215 DOI: 10.1002/cbic.202100453] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 10/13/2021] [Indexed: 12/02/2022]
Abstract
Nitrogenases are the only known family of enzymes that catalyze the reduction of molecular nitrogen (N2 ) to ammonia (NH3 ). The N2 reduction drives biological nitrogen fixation and the global nitrogen cycle. Besides the conversion of N2 , nitrogenases catalyze a whole range of other reductions, including the reduction of the small gaseous substrates carbon monoxide (CO) and carbon dioxide (CO2 ) to hydrocarbons. However, it remains an open question whether these 'side reactivities' play a role under environmental conditions. Nonetheless, these reactivities and particularly the formation of hydrocarbons have spurred the interest in nitrogenases for biotechnological applications. There are three different isozymes of nitrogenase: the molybdenum and the alternative vanadium and iron-only nitrogenase. The isozymes differ in their metal content, structure, and substrate-dependent activity, despite their homology. This minireview focuses on the conversion of CO and CO2 to methane and higher hydrocarbons and aims to specify the differences in activity between the three nitrogenase isozymes.
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Affiliation(s)
- Niels N. Oehlmann
- Max Planck Institute for Terrestrial MicrobiologyKarl-von-Frisch-Straße 1035043MarburgGermany
| | - Johannes G. Rebelein
- Max Planck Institute for Terrestrial MicrobiologyKarl-von-Frisch-Straße 1035043MarburgGermany
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15
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Solomon J, Tanifuji K, Lee CC, Jasniewski A, Hedman B, Hodgson K, Hu Y, Ribbe M. Characterization of a Nitrogenase Iron Protein Substituted with a Synthetic [Fe4Se4] Cluster. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202202271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
| | - Kazuki Tanifuji
- Kyoto University Institute for Chemical Research UNITED STATES
| | - Chi Chung Lee
- University of California Irvine Molecular Biology and Biochemistry UNITED STATES
| | - Andrew Jasniewski
- University of California Irvine Molecular Biology and Biochemistry UNITED STATES
| | - Britt Hedman
- Stanford University Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory UNITED STATES
| | | | - Yilin Hu
- University of California Irvine Molecular Biology and Biochemistry UNITED STATES
| | - Markus Ribbe
- Irvine Molecular Biology & Biochemistry 2236 McGaugh Hall 92697 Irvine UNITED STATES
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16
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Electron inventory of the iron-sulfur scaffold complex HypCD essential in [NiFe]-hydrogenase cofactor assembly. Biochem J 2021; 478:3281-3295. [PMID: 34409988 PMCID: PMC8454700 DOI: 10.1042/bcj20210224] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 08/17/2021] [Accepted: 08/19/2021] [Indexed: 11/17/2022]
Abstract
The [4Fe-4S] cluster containing scaffold complex HypCD is the central construction site for the assembly of the [Fe](CN)2CO cofactor precursor of [NiFe]-hydrogenase. While the importance of the HypCD complex is well established, not much is known about the mechanism by which the CN- and CO ligands are transferred and attached to the iron ion. We report an efficient expression and purification system producing the HypCD complex from E. coli with complete metal content. This enabled in-depth spectroscopic characterizations. The results obtained by EPR and Mössbauer spectroscopy demonstrate that the [Fe](CN)2CO cofactor and the [4Fe-4S] cluster of the HypCD complex are redox active. The data indicate a potential-dependent interconversion of the [Fe]2+/3+ and [4Fe-4S]2+/+ couple, respectively. Moreover, ATR FTIR spectroscopy reveals potential-dependent disulfide formation, which hints at an electron confurcation step between the metal centers. MicroScale thermophoresis indicates preferable binding between the HypCD complex and its in vivo interaction partner HypE under reducing conditions. Together, these results provide comprehensive evidence for an electron inventory fit to drive multi-electron redox reactions required for the assembly of the CN- and CO ligands on the scaffold complex HypCD.
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17
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Terranova U. Residues surrounding the active centre of carbon monoxide dehydrogenase are key in converting [Formula: see text] to CO. J Biol Inorg Chem 2021; 26:617-624. [PMID: 34255144 DOI: 10.1007/s00775-021-01878-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 06/17/2021] [Indexed: 10/20/2022]
Abstract
The enzyme carbon monoxide dehydrogenase is capable of efficiently converting [Formula: see text] to CO and, therefore, can enable an affordable [Formula: see text] recycling strategy. The reduction of [Formula: see text] occurs at a peculiar nickel-iron-sulfur cluster, following a mechanism that remains little understood. In this study, we have used ab initio molecular dynamics simulations to explore the free energy landscape of the reaction. We predict the existence of a COOH ligand that strongly interacts with the surrounding protein residues and favours a mechanism where a [Formula: see text] molecule is eliminated before CO. We have taken advantages of the insights offered by our simulations to revisit the catalytic mechanism and the role of the residues surrounding the active centre in particular, thus assisting in the design of inorganic catalysts that mimic the enzyme.
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Affiliation(s)
- Umberto Terranova
- Faculty of Medicine and Health Sciences, Crewe Campus, University of Buckingham, Crewe, CW1 5DU, UK.
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18
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Kang F, Yu L, Xia Y, Yu M, Xia L, Wang Y, Yang L, Wang T, Gong W, Tian C, Liu X, Wang J. Rational Design of a Miniature Photocatalytic CO 2-Reducing Enzyme. ACS Catal 2021. [DOI: 10.1021/acscatal.1c00287] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Fuying Kang
- Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lu Yu
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Yan Xia
- Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Minling Yu
- Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lin Xia
- Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Yuchuan Wang
- Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Lin Yang
- Hefei National Laboratory of Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei 230027, China
| | - Tianyuan Wang
- Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Weimin Gong
- Hefei National Laboratory of Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei 230027, China
| | - Changlin Tian
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui 230031, China
- Hefei National Laboratory of Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei 230027, China
| | - Xiaohong Liu
- Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Jiangyun Wang
- Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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19
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Solomon J, Rasekh MF, Hiller CJ, Lee CC, Tanifuji K, Ribbe MW, Hu Y. Probing the All-Ferrous States of Methanogen Nitrogenase Iron Proteins. JACS AU 2021; 1:119-123. [PMID: 34467276 PMCID: PMC8395668 DOI: 10.1021/jacsau.0c00072] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The Fe protein of nitrogenase reduces two C1 substrates, CO2 and CO, under ambient conditions when its [Fe4S4] cluster adopts the all-ferrous [Fe4S4]0 state. Here, we show disparate reactivities of the nifH- and vnf-encoded Fe proteins from Methanosarcina acetivorans (designated MaNifH and MaVnfH) toward C1 substrates in the all-ferrous state, with the former capable of reducing both CO2 and CO to hydrocarbons, and the latter only capable of reducing CO to hydrocarbons at substantially reduced yields. EPR experiments conducted at varying solution potentials reveal that MaVnfH adopts the all-ferrous state at a more positive reduction potential than MaNifH, which could account for the weaker reactivity of the MaVnfH toward C1 substrates than MaNifH. More importantly, MaVnfH already displays the g = 16.4 parallel-mode EPR signal that is characteristic of the all-ferrous [Fe4S4]0 cluster at a reduction potential of -0.44 V, and the signal reaches 50% maximum intensity at a reduction potential of -0.59 V, suggesting the possibility of this Fe protein to access the all-ferrous [Fe4S4]0 state under physiological conditions. These results bear significant relevance to the long-lasting debate of whether the Fe protein can utilize the [Fe4S4]0/2+ redox couple to support a two-electron transfer during substrate turnover which, therefore, is crucial for expanding our knowledge of the reaction mechanism of nitrogenase and the cellular energetics of nitrogenase-based processes.
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Affiliation(s)
- Joseph
B. Solomon
- Department
of Molecular Biology and Biochemistry, University
of California, Irvine, California 92697-3900, United States
- Department
of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Mahtab F. Rasekh
- Department
of Molecular Biology and Biochemistry, University
of California, Irvine, California 92697-3900, United States
- Department
of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Caleb J. Hiller
- Department
of Physical Science, Southern Utah University, Cedar City, Utah 84720, United States
| | - Chi Chung Lee
- Department
of Molecular Biology and Biochemistry, University
of California, Irvine, California 92697-3900, United States
| | - Kazuki Tanifuji
- Department
of Molecular Biology and Biochemistry, University
of California, Irvine, California 92697-3900, United States
| | - Markus W. Ribbe
- Department
of Molecular Biology and Biochemistry, University
of California, Irvine, California 92697-3900, United States
- Department
of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Yilin Hu
- Department
of Molecular Biology and Biochemistry, University
of California, Irvine, California 92697-3900, United States
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20
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Yilin Hu. Angew Chem Int Ed Engl 2020; 59:10694. [DOI: 10.1002/anie.202000302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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21
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Yilin Hu. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202000302] [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]
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22
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Abstract
Nitrogenase is the only enzyme capable of reducing N2 to NH3. This challenging reaction requires the coordinated transfer of multiple electrons from the reductase, Fe-protein, to the catalytic component, MoFe-protein, in an ATP-dependent fashion. In the last two decades, there have been significant advances in our understanding of how nitrogenase orchestrates electron transfer (ET) from the Fe-protein to the catalytic site of MoFe-protein and how energy from ATP hydrolysis transduces the ET processes. In this review, we summarize these advances, with focus on the structural and thermodynamic redox properties of nitrogenase component proteins and their complexes, as well as on new insights regarding the mechanism of ET reactions during catalysis and how they are coupled to ATP hydrolysis. We also discuss recently developed chemical, photochemical, and electrochemical methods for uncoupling substrate reduction from ATP hydrolysis, which may provide new avenues for studying the catalytic mechanism of nitrogenase.
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Affiliation(s)
- Hannah L Rutledge
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0340, United States
| | - F Akif Tezcan
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0340, United States
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23
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Jasniewski AJ, Lee CC, Ribbe MW, Hu Y. Reactivity, Mechanism, and Assembly of the Alternative Nitrogenases. Chem Rev 2020; 120:5107-5157. [PMID: 32129988 PMCID: PMC7491575 DOI: 10.1021/acs.chemrev.9b00704] [Citation(s) in RCA: 110] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Biological nitrogen fixation is catalyzed by the enzyme nitrogenase, which facilitates the cleavage of the relatively inert triple bond of N2. Nitrogenase is most commonly associated with the molybdenum-iron cofactor called FeMoco or the M-cluster, and it has been the subject of extensive structural and spectroscopic characterization over the past 60 years. In the late 1980s and early 1990s, two "alternative nitrogenase" systems were discovered, isolated, and found to incorporate V or Fe in place of Mo. These systems are regulated by separate gene clusters; however, there is a high degree of structural and functional similarity between each nitrogenase. Limited studies with the V- and Fe-nitrogenases initially demonstrated that these enzymes were analogously active as the Mo-nitrogenase, but more recent investigations have found capabilities that are unique to the alternative systems. In this review, we will discuss the reactivity, biosynthetic, and mechanistic proposals for the alternative nitrogenases as well as their electronic and structural properties in comparison to the well-characterized Mo-dependent system. Studies over the past 10 years have been particularly fruitful, though key aspects about V- and Fe-nitrogenases remain unexplored.
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Affiliation(s)
- Andrew J Jasniewski
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697-3900, United States
| | - Chi Chung Lee
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697-3900, United States
| | - Markus W Ribbe
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697-3900, United States
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Yilin Hu
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697-3900, United States
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24
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Tanifuji K, Ohki Y. Metal–Sulfur Compounds in N2 Reduction and Nitrogenase-Related Chemistry. Chem Rev 2020; 120:5194-5251. [DOI: 10.1021/acs.chemrev.9b00544] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Kazuki Tanifuji
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, California 92697-3900, United States
| | - Yasuhiro Ohki
- Department of Chemsitry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
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25
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Ahmed ME, Rana A, Saha R, Dey S, Dey A. Homogeneous Electrochemical Reduction of CO 2 to CO by a Cobalt Pyridine Thiolate Complex. Inorg Chem 2020; 59:5292-5302. [PMID: 32267696 DOI: 10.1021/acs.inorgchem.9b03056] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The chemical and electrochemical reduction of CO2 to value added chemicals entails the development of efficient and selective catalysts. Synthesis, characterization and electrochemical CO2 reduction activity of a air-stable cobalt(III) diphenylphosphenethano-bis(2-pyridinethiolate)chloride [{Co(dppe)(2-PyS)2}Cl, 1-Cl] complex is divulged. The complex reduces CO2 under homogeneous electrocatalytic conditions to produce CO with high Faradaic efficiency (FE > 92%) and selectivity in the presence of water. Through detailed electrochemical investigations, product analysis, and mechanistic investigations supported by theoretical calculations, it is established that complex 1-Cl reduces CO2 in its Co(I) state. A reductive cleavage leads to a dangling protonated pyridine arm which enables facile CO2 binding through a H-bond donation and facilitates the C-O bond cleavage via a directed protonation. A systematic benchmarking of this catalyst indicates that it has a modest overpotential (∼180 mV) and a TOF of ∼20 s-1 for selective reduction of CO2 to CO with H2O as a proton source.
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Affiliation(s)
- Md Estak Ahmed
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S.C. Mullick Road, Kolkata 700032, India
| | - Atanu Rana
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S.C. Mullick Road, Kolkata 700032, India
| | - Rajat Saha
- Department of Chemistry, Kazi Nazrul University, Kalla, Asansol, Paschim Bardhaman 713340, India
| | - Subal Dey
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S.C. Mullick Road, Kolkata 700032, India
| | - Abhishek Dey
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S.C. Mullick Road, Kolkata 700032, India
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26
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Jeoung JH, Martins BM, Dobbek H. Double-Cubane [8Fe9S] Clusters: A Novel Nitrogenase-Related Cofactor in Biology. Chembiochem 2020; 21:1710-1716. [PMID: 32187824 PMCID: PMC7317905 DOI: 10.1002/cbic.202000016] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 02/14/2020] [Indexed: 12/20/2022]
Abstract
Three different types of electron-transferring metallo-ATPases are able to couple ATP hydrolysis to the reduction of low-potential metal sites, thereby energizing an electron. Besides the Fe-protein known from nitrogenase and homologous enzymes, two other kinds of ATPase with different scaffolds and cofactors are used to achieve a unidirectional, energetic, uphill electron transfer to either reduce inactive Co-corrinoid-containing proteins (RACE-type activators) or a second iron-sulfur cluster-containing enzyme of a unique radical enzymes family (archerases). We have found a new cofactor in the latter enzyme family, that is, a double-cubane cluster with two [4Fe4S] subclusters bridged by a sulfido ligand. An enzyme containing this cofactor catalyzes the ATP-dependent reduction of small molecules, including acetylene. Thus, enzymes containing the double-cubane cofactor are analogous in function and share some structural features with nitrogenases.
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Affiliation(s)
- Jae-Hun Jeoung
- Institut für Biologie, Strukturbiologie/Biochemie, Humboldt-Universität zu Berlin, Unter den Linden 6, 10099, Berlin, Germany
| | - Berta M Martins
- Institut für Biologie, Strukturbiologie/Biochemie, Humboldt-Universität zu Berlin, Unter den Linden 6, 10099, Berlin, Germany
| | - Holger Dobbek
- Institut für Biologie, Strukturbiologie/Biochemie, Humboldt-Universität zu Berlin, Unter den Linden 6, 10099, Berlin, Germany
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27
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Shan C, Yao S, Driess M. Where silylene–silicon centres matter in the activation of small molecules. Chem Soc Rev 2020; 49:6733-6754. [DOI: 10.1039/d0cs00815j] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Small molecules such as H2, N2, CO, NH3, O2 are ubiquitous stable species and their activation and role in the formation of value-added products are of fundamental importance in nature and industry.
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Affiliation(s)
- Changkai Shan
- Department of Chemistry
- Metalorganics and Inorganic Materials
- Technische Universität Berlin
- 10623 Berlin
- Germany
| | - Shenglai Yao
- Department of Chemistry
- Metalorganics and Inorganic Materials
- Technische Universität Berlin
- 10623 Berlin
- Germany
| | - Matthias Driess
- Department of Chemistry
- Metalorganics and Inorganic Materials
- Technische Universität Berlin
- 10623 Berlin
- Germany
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28
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Rettberg LA, Stiebritz MT, Kang W, Lee CC, Ribbe MW, Hu Y. Structural and Mechanistic Insights into CO 2 Activation by Nitrogenase Iron Protein. Chemistry 2019; 25:13078-13082. [PMID: 31402524 DOI: 10.1002/chem.201903387] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 08/06/2019] [Indexed: 11/09/2022]
Abstract
The Fe protein of nitrogenase catalyzes the ambient reduction of CO2 when its cluster is present in the all-ferrous, [Fe4 S4 ]0 oxidation state. Here, we report a combined structural and theoretical study that probes the unique reactivity of the all-ferrous Fe protein toward CO2 . Structural comparisons of the Azotobacter vinelandii Fe protein in the [Fe4 S4 ]0 and [Fe4 S4 ]+ states point to a possible asymmetric functionality of a highly conserved Arg pair in CO2 binding and reduction. Density functional theory (DFT) calculations provide further support for the asymmetric coordination of O by the "proximal" Arg and binding of C to a unique Fe atom of the all-ferrous cluster, followed by donation of protons by the proximate guanidinium group of Arg that eventually results in the scission of a C-O bond. These results provide important mechanistic and structural insights into CO2 activation by a surface-exposed, scaffold-held [Fe4 S4 ] cluster.
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Affiliation(s)
- Lee A Rettberg
- Department of Molecular Biology & Biochemistry, University of California, Irvine, CA, 92697-3900, USA
| | - Martin T Stiebritz
- Department of Molecular Biology & Biochemistry, University of California, Irvine, CA, 92697-3900, USA
| | - Wonchull Kang
- Department of Molecular Biology & Biochemistry, University of California, Irvine, CA, 92697-3900, USA
| | - Chi Chung Lee
- Department of Molecular Biology & Biochemistry, University of California, Irvine, CA, 92697-3900, USA
| | - Markus W Ribbe
- Department of Molecular Biology & Biochemistry, University of California, Irvine, CA, 92697-3900, USA.,Department Chemistry, University of California, Irvine, Irvine, CA, 92697-2025, USA
| | - Yilin Hu
- Department of Molecular Biology & Biochemistry, University of California, Irvine, CA, 92697-3900, USA
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29
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Structural Analysis of a Nitrogenase Iron Protein from Methanosarcina acetivorans: Implications for CO 2 Capture by a Surface-Exposed [Fe 4S 4] Cluster. mBio 2019; 10:mBio.01497-19. [PMID: 31289188 PMCID: PMC6747716 DOI: 10.1128/mbio.01497-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
This work reports the crystal structure of a previously uncharacterized Fe protein from a methanogenic organism, which provides important insights into the structural properties of the less-characterized, yet highly interesting archaeal nitrogenase enzymes. Moreover, the structure-derived implications for CO2 capture by a surface-exposed [Fe4S4] cluster point to the possibility of developing novel strategies for CO2 sequestration while providing the initial insights into the unique mechanism of FeS-based CO2 activation. Nitrogenase iron (Fe) proteins reduce CO2 to CO and/or hydrocarbons under ambient conditions. Here, we report a 2.4-Å crystal structure of the Fe protein from Methanosarcina acetivorans (MaNifH), which is generated in the presence of a reductant, dithionite, and an alternative CO2 source, bicarbonate. Structural analysis of this methanogen Fe protein species suggests that CO2 is possibly captured in an unactivated, linear conformation near the [Fe4S4] cluster of MaNifH by a conserved arginine (Arg) pair in a concerted and, possibly, asymmetric manner. Density functional theory calculations and mutational analyses provide further support for the capture of CO2 on MaNifH while suggesting a possible role of Arg in the initial coordination of CO2 via hydrogen bonding and electrostatic interactions. These results provide a useful framework for further mechanistic investigations of CO2 activation by a surface-exposed [Fe4S4] cluster, which may facilitate future development of FeS catalysts for ambient conversion of CO2 into valuable chemical commodities.
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30
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Abstract
Biological nitrogen fixation, the conversion of dinitrogen (N2) into ammonia (NH3), stands as a particularly challenging chemical process. As the entry point into a bioavailable form of nitrogen, biological nitrogen fixation is a critical step in the global nitrogen cycle. In Nature, only one enzyme, nitrogenase, is competent in performing this reaction. Study of this complex metalloenzyme has revealed a potent substrate reduction system that utilizes some of the most sophisticated metalloclusters known. This chapter discusses the structure and function of nitrogenase, covers methods that have proven useful in the elucidation of enzyme properties, and provides an overview of the three known nitrogenase variants.
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31
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Lee CC, Stiebritz MT, Hu Y. Reactivity of [Fe 4S 4] Clusters toward C1 Substrates: Mechanism, Implications, and Potential Applications. Acc Chem Res 2019; 52:1168-1176. [PMID: 30977994 DOI: 10.1021/acs.accounts.9b00063] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
FeS proteins are metalloproteins prevalent in the metabolic pathways of most organisms, playing key roles in a wide range of essential cellular processes. A member of this protein family, the Fe protein of nitrogenase, is a homodimer that contains a redox-active [Fe4S4] cluster at the subunit interface and an ATP-binding site within each subunit. During catalysis, the Fe protein serves as the obligate electron donor for its catalytic partner, transferring electrons concomitant with ATP hydrolysis to the cofactor site of the catalytic component to enable substrate reduction. The effectiveness of Fe protein in electron transfer is reflected by the unique reactivity of nitrogenase toward small-molecule substrates. Most notably, nitrogenase is capable of catalyzing the ambient reduction of N2 and CO into NH4+ and hydrocarbons, respectively, in reactions that parallel the important industrial Haber-Bosch and Fischer-Tropsch processes. Other than participating in nitrogenase catalysis, the Fe protein also functions as an essential factor in nitrogenase assembly, which again highlights its capacity as an effective, ATP-dependent electron donor. Recently, the Fe protein of a soil bacterium, Azotobacter vinelandii, was shown to act as a reductase on its own and catalyze the ambient conversion of CO2 to CO at its [Fe4S4] cluster either under in vitro conditions when a strong reductant is supplied or under in vivo conditions through the action of an unknown electron donor(s) in the cell. Subsequently, the Fe protein of a mesophilic methanogenic organism, Methanosarcina acetivorans, was shown to catalyze the in vitro reduction of CO2 and CO into hydrocarbons under ambient conditions, illustrating an impact of protein scaffold on the redox properties of the [Fe4S4] cluster and the reactivity of the cluster toward C1 substrates. This reactivity was further traced to the [Fe4S4] cluster itself, as a synthetic [Fe4S4] compound was shown to catalyze the reduction of CO2 and CO to hydrocarbons in solutions in the presence of a strong reductant. Together, these observations pointed to an inherent ability of the [Fe4S4] clusters and, possibly, the FeS clusters in general to catalyze C1-substrate reduction. Theoretical calculations have led to the proposal of a plausible reaction pathway that involves the formation of hydrocarbons via aldehyde-like intermediates, providing an important framework for further mechanistic investigations of FeS-based activation and reduction of C1 substrates. In this Account, we summarize the recent work leading to the discovery of C1-substrate reduction by protein-bound and free [Fe4S4] clusters as well as the current mechanistic understanding of this FeS-based reactivity. In addition, we briefly discuss the evolutionary implications of this discovery and potential applications that could be developed to enable FeS-based strategies for the ambient recycling of unwanted C1 waste into useful chemical commodities.
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Affiliation(s)
- Chi Chung Lee
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697-3900, United States
| | - Martin T. Stiebritz
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697-3900, United States
| | - Yilin Hu
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697-3900, United States
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Abstract
Metalloproteins are challenging objects if we want to investigate their chemical reactivity with theoretical approaches such as density functional theory (DFT). The complexity of these biomolecules often requires us to find a compromise between accuracy and feasibility, one that is tailored to the questions we set out to answer. In this chapter, we discuss computational approaches to studying chemical reactions in metalloproteins and how to utilize the information hidden in homologous proteins.
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Affiliation(s)
- Martin T Stiebritz
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA, USA.
| | - Yilin Hu
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA, USA.
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33
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Liang S, Zong M, Lou W. Recent Advances in Enzymatic Catalysis for Preparation of High Value-Added Chemicals from Carbon Dioxide. ACTA CHIMICA SINICA 2019. [DOI: 10.6023/a19060240] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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34
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Liu X, Kang F, Hu C, Wang L, Xu Z, Zheng D, Gong W, Lu Y, Ma Y, Wang J. A genetically encoded photosensitizer protein facilitates the rational design of a miniature photocatalytic CO 2-reducing enzyme. Nat Chem 2018; 10:1201-1206. [PMID: 30397317 DOI: 10.1038/s41557-018-0150-4] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 08/30/2018] [Indexed: 12/31/2022]
Abstract
Photosensitizers, which harness light energy to upgrade weak reductants to strong reductants, are pivotal components of the natural and artificial photosynthesis machineries. However, it has proved difficult to enhance and expand their functions through genetic engineering. Here we report a genetically encoded, 27 kDa photosensitizer protein (PSP), which facilitates the rational design of miniature photocatalytic CO2-reducing enzymes. Visible light drives PSP efficiently into a long-lived triplet excited state (PSP*), which reacts rapidly with reduced nicotinamide adenine dinucleotide to generate a super-reducing radical (PSP•), which is strong enough to reduce many CO2-reducing catalysts. We determined the three-dimensional structure of PSP• at 1.8 Å resolution by X-ray crystallography. Genetic engineering enabled the site-specific attachment of a nickel-terpyridine complex and the modular optimization of the photochemical properties of PSP, the chromophore/catalytic centre distance and the catalytic centre microenvironment, which culminated in a miniature photocatalytic CO2-reducing enzyme that has a CO2/CO conversion quantum efficiency of 2.6%.
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Affiliation(s)
- Xiaohong Liu
- Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Science, Chaoyang District, Beijing, China
| | - Fuying Kang
- Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Science, Chaoyang District, Beijing, China.,College of Life Sciences and School of Future Technology, University of Chinese Academy of Sciences, Beijing, China
| | - Cheng Hu
- Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Science, Chaoyang District, Beijing, China.,College of Life Sciences and School of Future Technology, University of Chinese Academy of Sciences, Beijing, China
| | - Li Wang
- Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Science, Chaoyang District, Beijing, China.,College of Life Sciences and School of Future Technology, University of Chinese Academy of Sciences, Beijing, China
| | - Zhen Xu
- Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Science, Chaoyang District, Beijing, China
| | - Dandan Zheng
- Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Science, Chaoyang District, Beijing, China
| | - Weimin Gong
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science & Technology of China, Hefei, Anhui, China
| | - Yi Lu
- Center of Chemical Biology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Yanhe Ma
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Jiangyun Wang
- Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Science, Chaoyang District, Beijing, China. .,College of Life Sciences and School of Future Technology, University of Chinese Academy of Sciences, Beijing, China. .,Shenzhen Institute of Transfusion Medicine, Shenzhen Blood Center, Shenzhen, Guangdong, China.
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35
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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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36
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37
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Rupnik K, Lee CC, Hu Y, Ribbe MW, Hales BJ. A VTVH MCD and EPR Spectroscopic Study of the Maturation of the "Second" Nitrogenase P-Cluster. Inorg Chem 2018; 57:4719-4725. [PMID: 29611695 DOI: 10.1021/acs.inorgchem.8b00428] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The P-cluster of the nitrogenase MoFe protein is a [ Fe8 S7] cluster that mediates efficient transfer of electrons to the active site for substrate reduction. Arguably the most complex homometallic FeS cluster found in nature, the biosynthetic mechanism of the P-cluster is of considerable theoretical and synthetic interest to chemists and biochemists alike. Previous studies have revealed a biphasic assembly mechanism of the two P-clusters in the MoFe protein upon incubation with Fe protein and ATP, in which the first P-cluster is formed through fast fusion of a pair of [ Fe4 S4]+ clusters within 5 min and the second P-cluster is formed through slow fusion of the second pair of [ Fe4 S4]+ clusters in a period of 2 h. Here we report a VTVH MCD and EPR spectroscopic study of the biosynthesis of the slow-forming, second P-cluster within the MoFe protein. Our results show that the first major step in the formation of the second P-cluster is the conversion of one of the precursor [ Fe4 S4]+ clusters into the integer spin cluster [ Fe4 S3-4]α, a process aided by the assembly protein NifZ, whereas the second major biosynthetic step appears to be the formation of a diamagnetic cluster with a possible structure of [ Fe8 S7-8]β, which is eventually converted into the P-cluster.
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Affiliation(s)
- Kresimir Rupnik
- Department of Chemistry , Louisiana State University , Baton Rouge , Louisiana 70803 , United States
| | - Chi Chung Lee
- Department of Molecular Biology and Biochemistry , University of California , Irvine , California 92697 , United States
| | - Yilin Hu
- Department of Molecular Biology and Biochemistry , University of California , Irvine , California 92697 , United States
| | - Markus W Ribbe
- Department of Molecular Biology and Biochemistry , University of California , Irvine , California 92697 , United States
| | - Brian J Hales
- Department of Chemistry , Louisiana State University , Baton Rouge , Louisiana 70803 , United States
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38
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Noar JD, Bruno-Bárcena JM. Azotobacter vinelandii: the source of 100 years of discoveries and many more to come. MICROBIOLOGY-SGM 2018. [PMID: 29533747 DOI: 10.1099/mic.0.000643] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Azotobacter vinelandii has been studied for over 100 years since its discovery as an aerobic nitrogen-fixing organism. This species has proved useful for the study of many different biological systems, including enzyme kinetics and the genetic code. It has been especially useful in working out the structures and mechanisms of different nitrogenase enzymes, how they can function in oxic environments and the interactions of nitrogen fixation with other aspects of metabolism. Interest in studying A. vinelandii has waned in recent decades, but this bacterium still possesses great potential for new discoveries in many fields and commercial applications. The species is of interest for research because of its genetic pliability and natural competence. Its features of particular interest to industry are its ability to produce multiple valuable polymers - bioplastic and alginate in particular; its nitrogen-fixing prowess, which could reduce the need for synthetic fertilizer in agriculture and industrial fermentations, via coculture; its production of potentially useful enzymes and metabolic pathways; and even its biofuel production abilities. This review summarizes the history and potential for future research using this versatile microbe.
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Affiliation(s)
- Jesse D Noar
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina, USA
| | - Jose M Bruno-Bárcena
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina, USA
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39
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Abstract
Although the nitrogen-fixing enzyme nitrogenase critically requires both a reductase component (Fe protein) and a catalytic component, considerably more work has focused on the latter species. Properties of the catalytic component, which contains two highly complex metallocofactors and catalyzes the reduction of N2 into ammonia, understandably making it the “star” of nitrogenase. However, as its obligate redox partner, the Fe protein is a workhorse with multiple supporting roles in both cofactor maturation and catalysis. In particular, the nitrogenase Fe protein utilizes nucleotide binding and hydrolysis in concert with electron transfer to accomplish several tasks of critical importance. Aside from the ATP-coupled transfer of electrons to the catalytic component during substrate reduction, the Fe protein also functions in a maturase and insertase capacity to facilitate the biosynthesis of the two-catalytic component metallocofactors: fusion of the [Fe8S7] P-cluster and insertion of Mo and homocitrate to form the matured [(homocitrate)MoFe7S9C] M-cluster. These and key structural-functional relationships of the indispensable Fe protein and its complex with the catalytic component will be covered in this review.
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40
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Hiller CJ, Stiebritz MT, Lee CC, Liedtke J, Hu Y. Tuning Electron Flux through Nitrogenase with Methanogen Iron Protein Homologues. Chemistry 2017; 23:16152-16156. [PMID: 28984391 DOI: 10.1002/chem.201704378] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Indexed: 11/06/2022]
Abstract
Nitrogenase uses a reductase component called Fe protein to deliver electrons to its catalytic partner for substrate reduction. The essential role of Fe protein in catalysis makes it an ideal target for regulating the electron flux and enzymatic activity of nitrogenase without perturbing the cofactor site. This work reports that hybrids between the Fe protein homologs of Methanosarcina acetivorans and the catalytic components of Azotobacter vinelandii can trap substrate CO through reduced electron fluxes. In addition, homology modeling/in silico docking is used to define markers for binding energy and specificity between the component proteins that correlate with the experimentally determined activities. This homologue-based approach could be further developed to allow identification or design of hybrids between homologous nitrogenase components for mechanistic investigations of nitrogenase through capture of substrates/ intermediates or for transgenic expression of nitrogenase through synthetic biology.
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Affiliation(s)
- Caleb J Hiller
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, 92697-3900, USA
| | - Martin T Stiebritz
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, 92697-3900, USA
| | - Chi Chung Lee
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, 92697-3900, USA
| | - Jasper Liedtke
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, 92697-3900, USA
| | - Yilin Hu
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, 92697-3900, USA
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41
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Sickerman NS, Hu Y, Ribbe MW. Activation of CO
2
by Vanadium Nitrogenase. Chem Asian J 2017; 12:1985-1996. [DOI: 10.1002/asia.201700624] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Nathaniel S. Sickerman
- Department of Molecular Biology and Biochemistry University of California, Irvine Irvine CA 92697-3900 USA
| | - Yilin Hu
- Department of Molecular Biology and Biochemistry University of California, Irvine Irvine CA 92697-3900 USA
| | - Markus W. Ribbe
- Department of Molecular Biology and Biochemistry University of California, Irvine Irvine CA 92697-3900 USA
- Department of Chemistry University of California, Irvine Irvine CA 92697-2025 USA
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43
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The in vivo hydrocarbon formation by vanadium nitrogenase follows a secondary metabolic pathway. Nat Commun 2016; 7:13641. [PMID: 27976719 PMCID: PMC5172229 DOI: 10.1038/ncomms13641] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 10/17/2016] [Indexed: 11/24/2022] Open
Abstract
The vanadium (V)-nitrogenase of Azotobacter vinelandii catalyses the in vitro conversion of carbon monoxide (CO) to hydrocarbons. Here we show that an A. vinelandii strain expressing the V-nitrogenase is capable of in vivo reduction of CO to ethylene (C2H4), ethane (C2H6) and propane (C3H8). Moreover, we demonstrate that CO is not used as a carbon source for cell growth, being instead reduced to hydrocarbons in a secondary metabolic pathway. These findings suggest a possible role of the ancient nitrogenase as an evolutionary link between the carbon and nitrogen cycles on Earth and establish a solid foundation for biotechnological adaptation of a whole-cell approach to recycling carbon wastes into hydrocarbon products. Thus, this study has several repercussions for evolution-, environment- and energy-related areas.
Nitrogenases reduce inorganic nitrogen to organic ammonia in a crucial step of the nitrogen cycle. Here the authors show that the vanadium-nitrogenase of Azotobacter vinelandii can also catalyse the in vivo conversion of carbon monoxide to hydrocarbons in a secondary non-biosynthetic pathway.
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