1
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Hou X, Liu H, Huang H. Iron-catalyzed fluoroalkylative alkylsulfonylation of alkenes via radical-anion relay. Nat Commun 2024; 15:1480. [PMID: 38368406 PMCID: PMC10874428 DOI: 10.1038/s41467-024-45867-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 02/06/2024] [Indexed: 02/19/2024] Open
Abstract
Transition metal-catalyzed reductive difunctionalization of alkenes with alkyl halides is a powerful method for upgrading commodity chemicals into densely functionalized molecules. However, super stoichiometric amounts of metal reductant and the requirement of installing a directing group into alkenes to suppress the inherent β-H elimination bring great limitations to this type of reaction. We demonstrate herein that the difunctionalization of alkenes with two different alkyl halides is accessible via a radical-anion relay with Na2S2O4 as both reductant and sulfone-source. The Na2S2O4 together with the electron-shuttle catalyst is crucial to divert the mechanistic pathway toward the formation of alkyl sulfone anion instead of the previously reported alkylmetal intermediates. Mechanistic studies allow the identification of carbon-centered alkyl radical and sulfur-centered alkyl sulfone radical, which are in equilibrium via capture or extrusion of SO2 and could be converted to alkyl sulfone anion accelerated by iron electron-shuttle catalysis, leading to the observed high chemoselectivity.
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Affiliation(s)
- Xiaoya Hou
- Key Laboratory of Precision and Intelligent Chemistry and Department of Chemistry, University of Science and Technology of China, Hefei, P. R. China
| | - Hongchi Liu
- Key Laboratory of Precision and Intelligent Chemistry and Department of Chemistry, University of Science and Technology of China, Hefei, P. R. China
| | - Hanmin Huang
- Key Laboratory of Precision and Intelligent Chemistry and Department of Chemistry, University of Science and Technology of China, Hefei, P. R. China.
- Key Laboratory of Green and Precise Synthetic Chemistry and Applications, Ministry of Education, Huaibei Normal University, Huaibei, P. R. China.
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2
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Fasano A, Baffert C, Schumann C, Berggren G, Birrell JA, Fourmond V, Léger C. Kinetic Modeling of the Reversible or Irreversible Electrochemical Responses of FeFe-Hydrogenases. J Am Chem Soc 2024; 146:1455-1466. [PMID: 38166210 DOI: 10.1021/jacs.3c10693] [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: 01/04/2024]
Abstract
The enzyme FeFe-hydrogenase catalyzes H2 evolution and oxidation at an active site that consists of a [4Fe-4S] cluster bridged to a [Fe2(CO)3(CN)2(azadithiolate)] subsite. Previous investigations of its mechanism were mostly conducted on a few "prototypical" FeFe-hydrogenases, such as that from Chlamydomonas reinhardtii(Cr HydA1), but atypical hydrogenases have recently been characterized in an effort to explore the diversity of this class of enzymes. We aim at understanding why prototypical hydrogenases are active in either direction of the reaction in response to a small deviation from equilibrium, whereas the homologous enzyme from Thermoanaerobacter mathranii (Tam HydS) shows activity only under conditions of very high driving force, a behavior that was referred to as "irreversible catalysis". We follow up on previous spectroscopic studies and recent developments in the kinetic modeling of bidirectional reactions to investigate and compare the catalytic cycles of Cr HydA1 and Tam HydS under conditions of direct electron transfer with an electrode. We compare the hypothetical catalytic cycles described in the literature, and we show that the observed changes in catalytic activity as a function of potential, pH, and H2 concentration can be explained with the assumption that the same catalytic mechanism applies. This helps us identify which variations in properties of the catalytic intermediates give rise to the distinct "reversible" or "irreversible" catalytic behaviors.
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Affiliation(s)
- Andrea Fasano
- Laboratoire de Bioénergétique et Ingénierie des Protéines. CNRS, Aix Marseille Université, UMR, 7281 Marseille, France
| | - Carole Baffert
- Laboratoire de Bioénergétique et Ingénierie des Protéines. CNRS, Aix Marseille Université, UMR, 7281 Marseille, France
| | - Conrad Schumann
- Molecular Biomimetics, Department of Chemistry, Ångström Laboratory, Uppsala University, 75120 Uppsala, Sweden
| | - Gustav Berggren
- Molecular Biomimetics, Department of Chemistry, Ångström Laboratory, Uppsala University, 75120 Uppsala, Sweden
| | - James A Birrell
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, U.K
| | - Vincent Fourmond
- Laboratoire de Bioénergétique et Ingénierie des Protéines. CNRS, Aix Marseille Université, UMR, 7281 Marseille, France
| | - Christophe Léger
- Laboratoire de Bioénergétique et Ingénierie des Protéines. CNRS, Aix Marseille Université, UMR, 7281 Marseille, France
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3
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Corrigan PS, Majer SH, Silakov A. Evidence of Atypical Structural Flexibility of the Active Site Surrounding of an [FeFe] Hydrogenase from Clostridium beijerinkii. J Am Chem Soc 2023; 145:11033-11044. [PMID: 37163727 DOI: 10.1021/jacs.2c13458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
[FeFe] hydrogenase from Clostridium beijerinkii (CbHydA1) is an unusual hydrogenase in that it can withstand prolonged exposure to O2 by reversibly converting into an O2-protected, inactive state (Hinact). It has been indicated in the past that an atypical conformation of the "SC367CP" loop near the [2Fe]H portion of the six-iron active site (H-cluster) allows the Cys367 residue to adopt an "off-H+-pathway" orientation, promoting a facile transition of the cofactor to Hinact. Here, we investigated the electronic structure of the H-cluster in the oxidized state (Hox) that directly converts to Hinact under oxidizing conditions and the related CO-inhibited state (Hox-CO). We demonstrate that both states exhibit two distinct forms in electron paramagnetic resonance (EPR) spectroscopy. The ratio between the two forms is pH-dependent but also sensitive to the buffer choice. Our IR and EPR analyses illustrate that the spectral heterogeneity is due to a perturbation of the coordination environment of the H-cluster's [4Fe4S]H subcluster without affecting the [2Fe]H subcluster. Overall, we conclude that the observation of two spectral components per state is evidence of heterogeneity of the environment of the H-cluster likely associated with conformational mobility of the SCCP loop. Such flexibility may allow Cys367 to switch rapidly between off- and on-H+-pathway rotamers. Consequently, we believe such structural mobility may be the key to maintaining high enzymatic activity while allowing a facile transition to the O2-protected state.
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Affiliation(s)
- Patrick S Corrigan
- Pennsylvania State University, 104 Chemistry Building, University Park, Pennsylvania 16802, United States
| | - Sean H Majer
- Pennsylvania State University, 104 Chemistry Building, University Park, Pennsylvania 16802, United States
| | - Alexey Silakov
- Pennsylvania State University, 104 Chemistry Building, University Park, Pennsylvania 16802, United States
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4
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Martini MA, Bikbaev K, Pang Y, Lorent C, Wiemann C, Breuer N, Zebger I, DeBeer S, Span I, Bjornsson R, Birrell JA, Rodríguez-Maciá P. Binding of exogenous cyanide reveals new active-site states in [FeFe] hydrogenases. Chem Sci 2023; 14:2826-2838. [PMID: 36937599 PMCID: PMC10016341 DOI: 10.1039/d2sc06098a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 02/07/2023] [Indexed: 02/10/2023] Open
Abstract
[FeFe] hydrogenases are highly efficient metalloenyzmes for hydrogen conversion. Their active site cofactor (the H-cluster) is composed of a canonical [4Fe-4S] cluster ([4Fe-4S]H) linked to a unique organometallic di-iron subcluster ([2Fe]H). In [2Fe]H the two Fe ions are coordinated by a bridging 2-azapropane-1,3-dithiolate (ADT) ligand, three CO and two CN- ligands, leaving an open coordination site on one Fe where substrates (H2 and H+) as well as inhibitors (e.g. O2, CO, H2S) may bind. Here, we investigate two new active site states that accumulate in [FeFe] hydrogenase variants where the cysteine (Cys) in the proton transfer pathway is mutated to alanine (Ala). Our experimental data, including atomic resolution crystal structures and supported by calculations, suggest that in these two states a third CN- ligand is bound to the apical position of [2Fe]H. These states can be generated both by "cannibalization" of CN- from damaged [2Fe]H subclusters as well as by addition of exogenous CN-. This is the first detailed spectroscopic and computational characterisation of the interaction of exogenous CN- with [FeFe] hydrogenases. Similar CN--bound states can also be generated in wild-type hydrogenases, but do not form as readily as with the Cys to Ala variants. These results highlight how the interaction between the first amino acid in the proton transfer pathway and the active site tunes ligand binding to the open coordination site and affects the electronic structure of the H-cluster.
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Affiliation(s)
- Maria Alessandra Martini
- Department of Inorganic Spectroscopy, Max Planck Institute for Chemical Energy Conversion Stiftstraße 34-36 45470 Mülheim an der Ruhr Germany
| | - Konstantin Bikbaev
- Department of Chemistry and Pharmacy, Friedrich Alexander University Erlangen-Nürnberg Bioinorganic Chemistry Erlangen Germany
| | - Yunjie Pang
- Department of Inorganic Spectroscopy, Max Planck Institute for Chemical Energy Conversion Stiftstraße 34-36 45470 Mülheim an der Ruhr Germany
- College of Chemistry, Beijing Normal University 100875 Beijing China
| | - Christian Lorent
- Institut für Chemie, Technische Universität Berlin Straße des 17. Juni 135 10623 Berlin Germany
| | - Charlotte Wiemann
- Institut für Chemie, Technische Universität Berlin Straße des 17. Juni 135 10623 Berlin Germany
- Ruanda-Zentrum und Büro für Afrika-Kooperationen, Universität Koblenz-Landau, Universitätsstraße 1 56070 Koblenz Germany
| | - Nina Breuer
- Department of Inorganic Spectroscopy, Max Planck Institute for Chemical Energy Conversion Stiftstraße 34-36 45470 Mülheim an der Ruhr Germany
| | - Ingo Zebger
- Institut für Chemie, Technische Universität Berlin Straße des 17. Juni 135 10623 Berlin Germany
| | - Serena DeBeer
- Department of Inorganic Spectroscopy, Max Planck Institute for Chemical Energy Conversion Stiftstraße 34-36 45470 Mülheim an der Ruhr Germany
| | - Ingrid Span
- Department of Chemistry and Pharmacy, Friedrich Alexander University Erlangen-Nürnberg Bioinorganic Chemistry Erlangen Germany
| | - Ragnar Bjornsson
- Department of Inorganic Spectroscopy, Max Planck Institute for Chemical Energy Conversion Stiftstraße 34-36 45470 Mülheim an der Ruhr Germany
- Univ. Grenoble Alpes, CNRS, CEA, IRIG, Laboratoire de Chimie et Biologie des Métaux 17 Rue des Martyrs F-38054 Grenoble Cedex France
| | - James A Birrell
- Department of Inorganic Spectroscopy, Max Planck Institute for Chemical Energy Conversion Stiftstraße 34-36 45470 Mülheim an der Ruhr Germany
- School of Life Sciences, University of Essex Colchester CO4 3SQ UK
| | - Patricia Rodríguez-Maciá
- Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford South Parks Road Oxford OX1 3QR UK
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5
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Hu H, Li Y, Li Y, Sun Y, Li Y. Carbamoyl Manganese Complexes for Epoxidation of Alkenes and Cycloaddition of Epoxides to Carbon Dioxide. J Catal 2023. [DOI: 10.1016/j.jcat.2023.02.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
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6
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Garg S, Mishra V, Vega LF, Sharma RS, Dumée LF. Hydrogen Biosensing: Prospects, Parallels, and Challenges. Ind Eng Chem Res 2023. [DOI: 10.1021/acs.iecr.2c03965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Shafali Garg
- Department of Environmental Studies, Bioresources and Environmental Biotechnology Laboratory, University of Delhi, Delhi110007, India
| | - Vandana Mishra
- Department of Environmental Studies, Bioresources and Environmental Biotechnology Laboratory, University of Delhi, Delhi110007, India
- Centre for Inter-disciplinary Studies of Mountain & Hill Environment (CISMHE), University of Delhi, Delhi110007, India
- Delhi School of Climate Change and Sustainability, Institute of Eminence, University of Delhi, Delhi110007, India
| | - Lourdes F. Vega
- Khalifa University, Department of Chemical Engineering, Abu Dhabi127788, United Arab Emirates
- Khalifa University, Research, and Innovation Center on CO2 and Hydrogen, Abu Dhabi127788, United Arab Emirates
| | - Radhey Shyam Sharma
- Department of Environmental Studies, Bioresources and Environmental Biotechnology Laboratory, University of Delhi, Delhi110007, India
- Centre for Inter-disciplinary Studies of Mountain & Hill Environment (CISMHE), University of Delhi, Delhi110007, India
- Delhi School of Climate Change and Sustainability, Institute of Eminence, University of Delhi, Delhi110007, India
| | - Ludovic F. Dumée
- Khalifa University, Department of Chemical Engineering, Abu Dhabi127788, United Arab Emirates
- Khalifa University, Research, and Innovation Center on CO2 and Hydrogen, Abu Dhabi127788, United Arab Emirates
- Khalifa University, Center for Membrane and Advanced Water Technology, Abu Dhabi127788, United Arab Emirates
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7
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Huang R, Zhi N, Yu L, Li Y, Wu X, He J, Zhu H, Qiao J, Liu X, Tian C, Wang J, Dong M. Genetically Encoded Photosensitizer Protein Reduces Iron–Sulfur Clusters of Radical SAM Enzymes. ACS Catal 2023. [DOI: 10.1021/acscatal.2c05143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Rongrong Huang
- Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Ning Zhi
- Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Lu Yu
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Yaoyang Li
- Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Xiangyu Wu
- Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Jiale He
- Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Hongji Zhu
- Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Jianjun Qiao
- Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Xiaohong Liu
- Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Changlin Tian
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui 230031, China
- The First Affiliated Hospital of USTC, School of Life Sciences, Division of Life Sciences and Medicine, Joint Center for Biological Analytical Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Jiangyun Wang
- Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Min Dong
- Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
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8
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Kumar N, Kaur‐Ghumaan S. Synthesis, Characterization and Electrochemical Studies of bis(Monothiolato) {FeFe} Complexes [Fe
2
(μ‐SC
6
H
4
‐OMe‐
m
)
2
(CO)
5
L] (L=CO, PCy
3
, PPh
3
). ChemistrySelect 2022. [DOI: 10.1002/slct.202203392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
- Naveen Kumar
- Department of Chemistry University of Delhi Delhi 110007 India
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9
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Hu WY, Li K, Weitz A, Wen A, Kim H, Murray JC, Cheng R, Chen B, Naowarojna N, Grinstaff MW, Elliott SJ, Chen JS, Liu P. Light-Driven Oxidative Demethylation Reaction Catalyzed by a Rieske-Type Non-heme Iron Enzyme Stc2. ACS Catal 2022; 12:14559-14570. [PMID: 37168530 PMCID: PMC10168674 DOI: 10.1021/acscatal.2c04232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Rieske-type non-heme iron oxygenases/oxidases catalyze a wide range of transformations. Their applications in bioremediation or biocatalysis face two key barriers: the need of expensive NAD(P)H as a reductant and a proper reductase to mediate the electron transfer from NAD(P)H to the oxygenases. To bypass the need of both the reductase and NAD(P)H, using Rieske-type oxygenase (Stc2) catalyzed oxidative demethylation as the model system, we report Stc2 photocatalysis using eosin Y/sulfite as the photosensitizer/sacrificial reagent pair. In a flow-chemistry setting to separate the photo-reduction half-reaction and oxidation half-reaction, Stc2 photo-biocatalysis outperforms the Stc2-NAD(P)H-reductase (GbcB) system. In addition, in a few other selected Rieske enzymes (NdmA, CntA, and GbcA), and a flavin-dependent enzyme (iodotyrosine deiodinase, IYD), the eosin Y/sodium sulfite photo-reduction pair could also serve as the NAD(P)H-reductase surrogate to support catalysis, which implies the potential applicability of this photo-reduction system to other redox enzymes.
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Affiliation(s)
- Wei-Yao Hu
- School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Jiao Tong University, Shanghai200240, P. R. China
- Department of Chemistry, Boston University, Boston, Massachusetts02215, United States
| | - Kelin Li
- Department of Chemistry, Boston University, Boston, Massachusetts02215, United States
| | - Andrew Weitz
- Department of Chemistry, Boston University, Boston, Massachusetts02215, United States
| | - Aiwen Wen
- Department of Chemistry, Boston University, Boston, Massachusetts02215, United States
| | - Hyomin Kim
- Department of Chemistry, Boston University, Boston, Massachusetts02215, United States
| | - Jessica C. Murray
- Department of Chemistry, Boston University, Boston, Massachusetts02215, United States
| | - Ronghai Cheng
- Department of Chemistry, Boston University, Boston, Massachusetts02215, United States
| | - Baixiong Chen
- Department of Chemistry, Boston University, Boston, Massachusetts02215, United States
| | - Nathchar Naowarojna
- Department of Chemistry, Boston University, Boston, Massachusetts02215, United States
| | - Mark W. Grinstaff
- Department of Chemistry, Boston University, Boston, Massachusetts02215, United States
| | - Sean J. Elliott
- Department of Chemistry, Boston University, Boston, Massachusetts02215, United States
| | - Jie-Sheng Chen
- School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Jiao Tong University, Shanghai200240, P. R. China
| | - Pinghua Liu
- Department of Chemistry, Boston University, Boston, Massachusetts02215, United States
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10
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Bedendi G, Kulkarni A, Maroni P, Milton RD. Alternative Electron Donors for the Nitrogenase‐like Dark‐Operative Protochlorophyllide Oxidoreductase (DPOR). ChemElectroChem 2022. [DOI: 10.1002/celc.202200774] [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)
- Giada Bedendi
- University of Geneva Faculty of Science: Universite de Geneve Faculte des Sciences Inorganic and Analytical Chemistry SWITZERLAND
| | - Amogh Kulkarni
- University of Geneva Faculty of Science: Universite de Geneve Faculte des Sciences Inorganic and Analytical Chemistry SWITZERLAND
| | - Plinio Maroni
- University of Geneva Faculty of Science: Universite de Geneve Faculte des Sciences Inorganic and Analytical Chemistry SWITZERLAND
| | - Ross D Milton
- Universite de Geneve Faculte de Medecine Department of Inorganic and Analytical Chemistry Sciences IIQuai Ernest-Ansermet 30 1211 Geneva 4 SWITZERLAND
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11
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Sanchez MK, Wiley S, Reijerse E, Lubitz W, Birrell JA, Dyer RB. Time-Resolved Infrared Spectroscopy Reveals the pH-Independence of the First Electron Transfer Step in the [FeFe] Hydrogenase Catalytic Cycle. J Phys Chem Lett 2022; 13:5986-5990. [PMID: 35736652 PMCID: PMC9251755 DOI: 10.1021/acs.jpclett.2c01467] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 06/21/2022] [Indexed: 06/15/2023]
Abstract
[FeFe] hydrogenases are highly active catalysts for hydrogen conversion. Their active site has two components: a [4Fe-4S] electron relay covalently attached to the H2 binding site and a diiron cluster ligated by CO, CN-, and 2-azapropane-1,3-dithiolate (ADT) ligands. Reduction of the [4Fe-4S] site was proposed to be coupled with protonation of one of its cysteine ligands. Here, we used time-resolved infrared (TRIR) spectroscopy on the [FeFe] hydrogenase from Chlamydomonas reinhardtii (CrHydA1) containing a propane-1,3-dithiolate (PDT) ligand instead of the native ADT ligand. The PDT modification does not affect the electron transfer step to [4Fe-4S]H but prevents the enzyme from proceeding further through the catalytic cycle. We show that the rate of the first electron transfer step is independent of the pH, supporting a simple electron transfer rather than a proton-coupled event. These results have important implications for our understanding of the catalytic mechanism of [FeFe] hydrogenases and highlight the utility of TRIR.
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Affiliation(s)
- Monica
L. K. Sanchez
- Department
of Chemistry and Biochemistry, Montana State
University, Bozeman, Montana 59717, United States
- Department
of Chemistry, Emory University, Atlanta, Georgia 30030, United States
| | - Seth Wiley
- Department
of Chemistry, Emory University, Atlanta, Georgia 30030, United States
| | - Edward Reijerse
- Max
Planck Institute for Chemical Energy Conversion, Stiftstraße 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Wolfgang Lubitz
- 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
| | - R. Brian Dyer
- Department
of Chemistry, Emory University, Atlanta, Georgia 30030, United States
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12
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Senger M, Duan J, Pavliuk MV, Apfel UP, Haumann M, Stripp ST. Trapping an Oxidized and Protonated Intermediate of the [FeFe]-Hydrogenase Cofactor under Mildly Reducing Conditions. Inorg Chem 2022; 61:10036-10042. [PMID: 35729755 DOI: 10.1021/acs.inorgchem.2c00954] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The H-cluster is the catalytic cofactor of [FeFe]-hydrogenase, a metalloenzyme that catalyzes the formation of dihydrogen (H2). The catalytic diiron site of the H-cluster carries two cyanide and three carbon monoxide ligands, making it an excellent target for IR spectroscopy. In previous work, we identified an oxidized and protonated H-cluster species, whose IR signature differs from that of the oxidized resting state (Hox) by a small but distinct shift to higher frequencies. This "blue shift" was explained by a protonation at the [4Fe-4S] subcomplex of the H-cluster. The novel species, denoted HoxH, was preferentially accumulated at low pH and in the presence of the exogenous reductant sodium dithionite (NaDT). When HoxH was reacted with H2, the hydride state (Hhyd) was formed, a key intermediate of [FeFe]-hydrogenase turnover. A recent publication revisited our protocol for the accumulation of HoxH in wild-type [FeFe]-hydrogenase, concluding that inhibition by NaDT decay products rather than cofactor protonation causes the spectroscopic "blue shift". Here, we demonstrate that HoxH formation does not require the presence of NaDT (or its decay products), but accumulates also with the milder reductants tris(2-carboxyethyl)phosphine, dithiothreitol, or ascorbic acid, in particular at low pH. Our data consistently suggest that HoxH is accumulated when deprotonation of the H-cluster is impaired, thereby preventing the regain of the oxidized resting state Hox in the catalytic cycle.
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Affiliation(s)
- Moritz Senger
- Department of Chemistry, Physical Chemistry, Uppsala University, Uppsala 75120, Sweden
| | - Jifu Duan
- Faculty of Biology and Biotechnology, Photobiotechnology, Ruhr-Universität Bochum, Bochum 44801, Germany
| | - Mariia V Pavliuk
- Department of Chemistry, Physical Chemistry, Uppsala University, Uppsala 75120, Sweden
| | - Ulf-Peter Apfel
- Faculty of Chemistry and Biochemistry, Small Molecule Activation, Ruhr-Universität Bochum, Bochum 44801, Germany.,Electrosynthesis, Fraunhofer UMSICHT, Oberhausen 46047, Germany
| | - Michael Haumann
- Department of Physics, Biophysics of Metalloenzymes, Freie Universität Berlin, Berlin 14195, Germany
| | - Sven T Stripp
- Department of Physics, Experimental Molecular Biophysics, Freie Universität Berlin, Berlin 14195, Germany
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13
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Hu XY, Li JJ, Yang ZW, Zhang J, Wang HS. Fluorescent intracellular imaging of reactive oxygen species and pH levels moderated by a hydrogenase mimic in living cells. J Pharm Anal 2022; 12:801-807. [PMID: 36320605 PMCID: PMC9615531 DOI: 10.1016/j.jpha.2022.05.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 05/12/2022] [Accepted: 05/22/2022] [Indexed: 11/17/2022] Open
Abstract
The catalytic generation of H2 in living cells provides a method for antioxidant therapy. In this study, an [FeFe]-hydrogenase mimic [Ru + Fe2S2@F127(80)] was synthesized by self-assembling polymeric pluronic F-127, catalytic [Fe2S2] sites, and photosensitizer Ru(bpy)32+. Under blue light irradiation, hydrated protons were photochemically reduced to H2, which increased the local pH in living cells (HeLa cells). The generated H2 was subsequently used as an antioxidant to decrease reactive oxygen species (ROS) levels in living cells (HEK 293T, HepG2, MCF-7, and HeLa cells). Our findings revealed that the proliferation of HEK 293T cells increased by a factor of about six times, relative to that of other cells (HepG2, MCF-7, and HeLa cells). Intracellular ROS and pH levels were then monitored using fluorescent cell imaging. Our study showed that cell imaging can be used to evaluate the ability of Ru + Fe2S2@F127 to eliminate oxidative stress and prevent ROS-related diseases. An [FeFe]-hydrogenase mimic was synthesized for H2 photogeneration. The catalytic generation of H2 was evaluated in HEK 293T cells. The H2 generated by Ru + Fe2S2@F127(80) was able to decrease ROS levels. Light irradiation of Ru + Fe2S2@F127(80) led to an increase in intracellular pH.
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Schmidl D, Jonasson NSW, Menke A, Schneider S, Daumann L. Spectroscopic and in vitro investigations of Fe2+/α-Ketoglutarate-dependent enzymes involved in nucleic acid repair and modification. Chembiochem 2022; 23:e202100605. [PMID: 35040547 PMCID: PMC9401043 DOI: 10.1002/cbic.202100605] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/14/2022] [Indexed: 11/08/2022]
Abstract
The activation of molecular oxygen for the highly selective functionalization and repair of DNA and RNA nucleobases is achieved by α-ketoglutarate (α-KG)/iron-dependent dioxygenases. Enzymes of special interest are the human homologs AlkBH of Escherichia coli EcAlkB and ten-eleven translocation (TET) enzymes. These enzymes are involved in demethylation or dealkylation of DNA and RNA, although additional physiological functions are continuously being revealed. Given their importance, studying enzyme-substrate interactions, turnover and kinetic parameters is pivotal for the understanding of the mode of action of these enzymes. Diverse analytical methods, including X-ray crystallography, UV/Vis absorption, electron paramagnetic resonance (EPR), circular dichroism (CD) and NMR spectroscopy have been employed to study the changes in the active site and the overall enzyme structure upon substrate, cofactor and inhibitor addition. Several methods are now available to assess activity of these enzymes. By discussing limitations and possibilities of these techniques for EcAlkB, AlkBH and TET we aim to give a comprehensive synopsis from a bioinorganic point of view, addressing researchers from different disciplines working in the highly interdisciplinary and rapidly evolving field of epigenetic processes and DNA/RNA repair and modification.
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Affiliation(s)
- David Schmidl
- Ludwig-Maximilians-Universität München: Ludwig-Maximilians-Universitat Munchen, Chemistry, GERMANY
| | - Niko S W Jonasson
- Ludwig-Maximilians-Universität München: Ludwig-Maximilians-Universitat Munchen, Chemistry, GERMANY
| | - Annika Menke
- Ludwig-Maximilians-Universität München: Ludwig-Maximilians-Universitat Munchen, Chemistry, GERMANY
| | - Sabine Schneider
- Ludwig-Maximilians-Universität München: Ludwig-Maximilians-Universitat Munchen, Chemistry, GERMANY
| | - Lena Daumann
- Ludwig-Maximilians-Universität München, Department of Chemistry, Butenandtstr. 5-13, 81377, München, GERMANY
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15
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Senger M, Kernmayr T, Lorenzi M, Redman HJ, Berggren G. Hydride state accumulation in native [FeFe]-hydrogenase with the physiological reductant H2 supports its catalytic relevance. Chem Commun (Camb) 2022; 58:7184-7187. [PMID: 35670542 PMCID: PMC9219605 DOI: 10.1039/d2cc00671e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Small molecules in solution may interfere with mechanistic investigations, as they can affect the stability of catalytic states and produce off-cycle states that can be mistaken for catalytically relevant species. Here we show that the hydride state (Hhyd), a proposed central intermediate in the catalytic cycle of [FeFe]-hydrogenase, can be formed in wild-type [FeFe]-hydrogenases treated with H2 in absence of other, non-biological, reductants. Moreover, we reveal a new state with unclear role in catalysis induced by common low pH buffers. Studies of enzymatic catalysis often rely on non-biological reagents, which may affect catalytic intermediates and produce off-cycle states. Here the influence of buffer and reductant on key intermediates of [FeFe]-hydrogenase are explored.![]()
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Affiliation(s)
- Moritz Senger
- Department of Chemistry, Physical Chemistry, Uppsala University, 75120 Uppsala, Sweden.
| | - Tobias Kernmayr
- Department of Chemistry, Molecular Biomimetics, Uppsala University, 75120 Uppsala, Sweden.
| | - Marco Lorenzi
- Department of Chemistry, Molecular Biomimetics, Uppsala University, 75120 Uppsala, Sweden.
| | - Holly J Redman
- Department of Chemistry, Molecular Biomimetics, Uppsala University, 75120 Uppsala, Sweden.
| | - Gustav Berggren
- Department of Chemistry, Molecular Biomimetics, Uppsala University, 75120 Uppsala, Sweden.
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16
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Redman HJ, Huang P, Haumann M, Cheah MH, Berggren G. Lewis acid protection turns cyanide containing [FeFe]-hydrogenase mimics into proton reduction catalysts. Dalton Trans 2022; 51:4634-4643. [PMID: 35212328 PMCID: PMC8939051 DOI: 10.1039/d1dt03896f] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Sustainable sources of hydrogen are a vital component of the envisioned energy transition. Understanding and mimicking the [FeFe]-hydrogenase provides a route to achieving this goal. In this study we re-visit a molecular mimic of the hydrogenase, the propyl dithiolate bridged complex [Fe2(μ-pdt)(CO)4(CN)2]2−, in which the cyanide ligands are tuned via Lewis acid interactions. This system provides a rare example of a cyanide containing [FeFe]-hydrogenase mimic capable of catalytic proton reduction, as demonstrated by cyclic voltammetry. EPR, FTIR, UV-vis and X-ray absorption spectroscopy are employed to characterize the species produced by protonation, and reduction or oxidation of the complex. The results reveal that biologically relevant iron-oxidation states can be generated, potentially including short-lived mixed valent Fe(i)Fe(ii) species. We propose that catalysis is initiated by protonation of the diiron complex and the resulting di-ferrous bridging hydride species can subsequently follow two different pathways to promote H2 gas formation depending on the applied reduction potential. Mimicking the hydrogen-bonding interactions of the [FeFe]-hydrogenase active-site using Lewis acids transforms an otherwise unstable cyanide containing hydrogenase mimic into a proton reduction catalyst.![]()
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Affiliation(s)
- Holly J Redman
- Department of Chemistry - Ångström Laboratory, Uppsala University, Box 523, 75120 Uppsala, Sweden.
| | - Ping Huang
- Department of Chemistry - Ångström Laboratory, Uppsala University, Box 523, 75120 Uppsala, Sweden.
| | - Michael Haumann
- Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Mun Hon Cheah
- Department of Chemistry - Ångström Laboratory, Uppsala University, Box 523, 75120 Uppsala, Sweden.
| | - Gustav Berggren
- Department of Chemistry - Ångström Laboratory, Uppsala University, Box 523, 75120 Uppsala, Sweden.
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