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Kass D, Katz S, Özgen H, Mebs S, Haumann M, García-Serres R, Dau H, Hildebrandt P, Lohmiller T, Ray K. A Bioinspired Nonheme Fe III-(O 22-)-Cu II Complex with an St = 1 Ground State. J Am Chem Soc 2024. [PMID: 38967560 DOI: 10.1021/jacs.4c04492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/06/2024]
Abstract
Cytochrome c oxidase (CcO) is a heme copper oxidase (HCO) that catalyzes the natural reduction of oxygen to water. A profound understanding of some of the elementary steps leading to the intricate 4e-/4H+ reduction of O2 is presently lacking. A total spin St = 1 FeIII-(O22-)-CuII (IP) intermediate is proposed to reduce the overpotentials associated with the reductive O-O bond rupture by allowing electron transfer from a tyrosine moiety without the necessity of any spin-surface crossing. Direct evidence of the involvement of IP in the CcO catalytic cycle is, however, missing. A number of heme copper peroxido complexes have been prepared as synthetic models of IP, but all of them possess the catalytically nonrelevant St = 0 ground state resulting from antiferromagnetic coupling between the S = 1/2 FeIII and CuII centers. In a complete nonheme approach, we now report the spectroscopic characterization and reactivity of the FeIII-(O22-)-CuII intermediates 1 and 2, which differ only by a single -CH3 versus -H substituent on the central amine of the tridentate ligands binding to copper. Complex 1 with an end-on peroxido core and ferromagnetically (St = 1) coupled FeIII and CuII centers performs H-bonding-mediated O-O bond cleavage in the presence of phenol to generate oxoiron(IV) and exchange-coupled copper(II) and PhO• moieties. In contrast, the μ-η2:η1 peroxido complex 2, with a St = 0 ground state, is unreactive toward phenol. Thus, the implications for spin topology contributions to O-O bond cleavage, as proposed for the heme FeIII-(O22-)-CuII intermediate in CcO, can be extended to nonheme chemistry.
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Affiliation(s)
- Dustin Kass
- Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Straße 2, 12489 Berlin, Germany
| | - Sagie Katz
- Department of Chemistry, Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany
| | - Hivda Özgen
- Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Straße 2, 12489 Berlin, Germany
| | - Stefan Mebs
- Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Michael Haumann
- Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Ricardo García-Serres
- Université Grenoble Alpes, CEA, CNRS, Laboratoire de Chimie et Biologie des Métaux, 38000 Grenoble, France
| | - Holger Dau
- Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Peter Hildebrandt
- Department of Chemistry, Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany
| | - Thomas Lohmiller
- Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Straße 2, 12489 Berlin, Germany
- EPR4Energy Joint Lab, Department Spins in Energy Conversion and Quantum Information Science, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Straße 16, 12489 Berlin, Germany
| | - Kallol Ray
- Institut für Chemie, Humboldt-Universität zu Berlin, Brook-Taylor-Straße 2, 12489 Berlin, Germany
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Lehnert N, Kim E, Dong HT, Harland JB, Hunt AP, Manickas EC, Oakley KM, Pham J, Reed GC, Alfaro VS. The Biologically Relevant Coordination Chemistry of Iron and Nitric Oxide: Electronic Structure and Reactivity. Chem Rev 2021; 121:14682-14905. [PMID: 34902255 DOI: 10.1021/acs.chemrev.1c00253] [Citation(s) in RCA: 92] [Impact Index Per Article: 30.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Nitric oxide (NO) is an important signaling molecule that is involved in a wide range of physiological and pathological events in biology. Metal coordination chemistry, especially with iron, is at the heart of many biological transformations involving NO. A series of heme proteins, nitric oxide synthases (NOS), soluble guanylate cyclase (sGC), and nitrophorins, are responsible for the biosynthesis, sensing, and transport of NO. Alternatively, NO can be generated from nitrite by heme- and copper-containing nitrite reductases (NIRs). The NO-bearing small molecules such as nitrosothiols and dinitrosyl iron complexes (DNICs) can serve as an alternative vehicle for NO storage and transport. Once NO is formed, the rich reaction chemistry of NO leads to a wide variety of biological activities including reduction of NO by heme or non-heme iron-containing NO reductases and protein post-translational modifications by DNICs. Much of our understanding of the reactivity of metal sites in biology with NO and the mechanisms of these transformations has come from the elucidation of the geometric and electronic structures and chemical reactivity of synthetic model systems, in synergy with biochemical and biophysical studies on the relevant proteins themselves. This review focuses on recent advancements from studies on proteins and model complexes that not only have improved our understanding of the biological roles of NO but also have provided foundations for biomedical research and for bio-inspired catalyst design in energy science.
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Affiliation(s)
- Nicolai Lehnert
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Eunsuk Kim
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Hai T Dong
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Jill B Harland
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Andrew P Hunt
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Elizabeth C Manickas
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Kady M Oakley
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - John Pham
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Garrett C Reed
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Victor Sosa Alfaro
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
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3
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Kim H, Sharma SK, Schaefer AW, Solomon EI, Karlin KD. Heme-Cu Binucleating Ligand Supports Heme/O 2 and Fe II-Cu I/O 2 Reactivity Providing High- and Low-Spin Fe III-Peroxo-Cu II Complexes. Inorg Chem 2019; 58:15423-15432. [PMID: 31657921 DOI: 10.1021/acs.inorgchem.9b02521] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The focus of this study is in the description of synthetic heme/copper/O2 chemistry employing a heme-containing binucleating ligand which provides a tridentate chelate for copper ion binding. The addition of O2 (-80 °C, tetrahydrofuran (THF) solvent) to the reduced heme compound (PImH)FeII (1), gives the oxy-heme adduct, formally a heme-superoxide complex FeIII-(O2•-) (2) (resonance Raman spectroscopy (rR): νO-O, 1171 cm-1 (Δ18O2, -61 cm-1); νFe-O, 575 cm-1 (Δ18O2, -24 cm-1)). Simple warming of 2 to room temperature regenerates reduced complex 1; this reaction is reversible, as followed by UV-vis spectroscopy. Complex 2 is electron paramagnetic resonance (EPR)-silent and exhibits upfield-shifted pyrrole resonances (δ 9.12 ppm) in 2H NMR spectroscopy, indicative of a six-coordinate low-spin heme. The coordination of the tethered imidazolyl arm to the heme-superoxide complex as an axial base ligand is suggested. We also report the new fully reduced heme-copper complex [(PImH)FeIICuI]+ (3), where the copper ion is bound to the tethered tridentate portion of PImH. This reacts with O2 to give a distinctive low-temperature-stable, high-spin (S = 2, overall) peroxo-bridged complex [(PImH)FeIII-(O22-)-CuII]+ (3a): λmax, 420 (Soret), 545, 565 nm; δpyrr, 93 ppm; νO-O, 799 cm-1 (Δ18O2, -48 cm-1); νFe-O, 524 cm-1 (Δ18O2, -23 cm-1). To 3a, the addition of dicyclohexylimidazole (DCHIm), which serves as a heme axial base, leads to low-spin (S = 0 overall) species complex [(DCHIm)(PImH)FeIII-(O22-)-CuII]+ (3b): λmax, 425 (Soret), 538 nm; δpyrr, 10.2 ppm; νO-O, 817 cm-1 (Δ18O2, -55 cm-1); νFe-O, 610 cm-1 (Δ18O2, -26 cm-1). These investigations into the characterization of the O2-adducts from (PImH)FeII (1) with/without additional copper chelation advance our understanding of the dioxygen reactivity of heme-only and heme/Cu-ligand heterobinuclear system, thus potentially relevant to O2 reduction in heme-copper oxidases or fuel-cell chemistry.
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Affiliation(s)
- Hyun Kim
- Department of Chemistry , Johns Hopkins University , Baltimore , Maryland 21218 , United States
| | - Savita K Sharma
- Department of Chemistry , Johns Hopkins University , Baltimore , Maryland 21218 , United States
| | - Andrew W Schaefer
- Department of Chemistry , Stanford University , Stanford , California 94305 , United States
| | - Edward I Solomon
- Department of Chemistry , Stanford University , Stanford , California 94305 , United States
| | - Kenneth D Karlin
- Department of Chemistry , Johns Hopkins University , Baltimore , Maryland 21218 , United States
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4
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Adam SM, Wijeratne GB, Rogler PJ, Diaz DE, Quist DA, Liu JJ, Karlin KD. Synthetic Fe/Cu Complexes: Toward Understanding Heme-Copper Oxidase Structure and Function. Chem Rev 2018; 118:10840-11022. [PMID: 30372042 PMCID: PMC6360144 DOI: 10.1021/acs.chemrev.8b00074] [Citation(s) in RCA: 132] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Heme-copper oxidases (HCOs) are terminal enzymes on the mitochondrial or bacterial respiratory electron transport chain, which utilize a unique heterobinuclear active site to catalyze the 4H+/4e- reduction of dioxygen to water. This process involves a proton-coupled electron transfer (PCET) from a tyrosine (phenolic) residue and additional redox events coupled to transmembrane proton pumping and ATP synthesis. Given that HCOs are large, complex, membrane-bound enzymes, bioinspired synthetic model chemistry is a promising approach to better understand heme-Cu-mediated dioxygen reduction, including the details of proton and electron movements. This review encompasses important aspects of heme-O2 and copper-O2 (bio)chemistries as they relate to the design and interpretation of small molecule model systems and provides perspectives from fundamental coordination chemistry, which can be applied to the understanding of HCO activity. We focus on recent advancements from studies of heme-Cu models, evaluating experimental and computational results, which highlight important fundamental structure-function relationships. Finally, we provide an outlook for future potential contributions from synthetic inorganic chemistry and discuss their implications with relevance to biological O2-reduction.
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Affiliation(s)
- Suzanne M. Adam
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Gayan B. Wijeratne
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Patrick J. Rogler
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Daniel E. Diaz
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - David A. Quist
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Jeffrey J. Liu
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Kenneth D. Karlin
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
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5
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6
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Elrod LT, Kim E. Lewis Acid Assisted Nitrate Reduction with Biomimetic Molybdenum Oxotransferase Complex. Inorg Chem 2018; 57:2594-2602. [PMID: 29443517 DOI: 10.1021/acs.inorgchem.7b02956] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reduction of nitrate (NO3-) to nitrite (NO2-) is of significant biological and environmental importance. While MoIV(O) and MoVI(O)2 complexes that mimic the active site structure of nitrate reducing enzymes are prevalent, few of these model complexes can reduce nitrate to nitrite through oxygen atom transfer (OAT) chemistry. We present a novel strategy to induce nitrate reduction chemistry of a previously known catalyst MoIV(O)(SN)2 (2), where SN = bis(4- tert-butylphenyl)-2-pyridylmethanethiolate, that is otherwise incapable of achieving OAT with nitrate. Addition of nitrate with the Lewis acid Sc(OTf)3 (OTf = trifluoromethanesulfonate) to 2 results in an immediate and clean conversion of 2 to MoVI(O)2(SN)2 (1). The Lewis acid additive further reacts with the OAT product, nitrite, to form N2O and O2. This work highlights the ability of Sc3+ additives to expand the reactivity scope of an existing MoIV(O) complex together with which Sc3+ can convert nitrate to stable gaseous molecules.
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Affiliation(s)
- Lee Taylor Elrod
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Eunsuk Kim
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
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7
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Götz R, Ly HK, Wrzolek P, Schwalbe M, Weidinger IM. Surface enhanced resonance Raman spectroscopy of iron Hangman complexes on electrodes during electrocatalytic oxygen reduction: advantages and problems of common drycast methods. Dalton Trans 2017; 46:13220-13228. [PMID: 28682383 DOI: 10.1039/c7dt01174a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Drycast methods have been used frequently in recent decades to adsorb a range of synthetic catalysts on electrodes. The uncoordinated multilayers that are formed via this immobilization method can however have a strong impact on the electrocatalytic reaction pathway as slow electron transfer and intermolecular interactions can alter the chemistry of the catalysts on the surface. To gain insight into the structure of Fe porphyrin Hangman catalysts during electrocatalytic oxygen reduction a combination of electrochemistry and surface enhanced resonance Raman spectroscopy (SERRS) was applied. The Hangman complexes were attached to the electrodes via different methods and the influence of the immobilisation technique on oxygen chemistry was studied. In multilayer systems, new intermediates could be identified via potential dependent SERRS that were not present in solution or in monolayer systems under catalytic conditions. A comparison of Raman spectra obtained either via Soret or Q-band excitation showed that the porphyrin symmetry is strongly distorted under reducing conditions, which was interpreted by the transient formation of dimer complexes during catalysis.
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Affiliation(s)
- R Götz
- Fachbereich Chemie und Lebensmittelchemie, Technische Universitaet Dresden, 01062 Dresden, Germany.
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8
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Boitrel B, Hijazi I, Roisnel T, Oohora K, Hayashi T. Iron-Strapped Porphyrins with Carboxylic Acid Groups Hanging over the Coordination Site: Synthesis, X-ray Characterization, and Dioxygen Binding. Inorg Chem 2017; 56:7373-7383. [DOI: 10.1021/acs.inorgchem.7b00343] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Bernard Boitrel
- Institut
des Sciences Chimiques de
Rennes, UMR CNRS 6226, Université de Rennes 1, 35042 Rennes Cedex, France
| | - Ismail Hijazi
- Institut
des Sciences Chimiques de
Rennes, UMR CNRS 6226, Université de Rennes 1, 35042 Rennes Cedex, France
| | - Thierry Roisnel
- Institut
des Sciences Chimiques de
Rennes, UMR CNRS 6226, Université de Rennes 1, 35042 Rennes Cedex, France
| | - Koji Oohora
- Department
of Applied Chemistry, Graduate School of Engineering, Osaka University, Yamadaoka
2-1, Suita, Osaka 565-0871, Japan
| | - Takashi Hayashi
- Department
of Applied Chemistry, Graduate School of Engineering, Osaka University, Yamadaoka
2-1, Suita, Osaka 565-0871, Japan
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9
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Ly HK, Wrzolek P, Heidary N, Götz R, Horch M, Kozuch J, Schwalbe M, Weidinger IM. 2 nd coordination sphere controlled electron transfer of iron hangman complexes on electrodes probed by surface enhanced vibrational spectroscopy. Chem Sci 2015; 6:6999-7007. [PMID: 29861938 PMCID: PMC5947519 DOI: 10.1039/c5sc02560e] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 09/04/2015] [Indexed: 12/14/2022] Open
Abstract
Surface enhanced vibrational spectroscopy shows the correlation between electron transfer kinetics and protonation degree of Fe Hangman complexes on electrodes.
Iron hangman complexes exhibit improved catalytic properties regarding O2 and H2O2 reduction, which are attributed to the presence of a proton donating group in defined vicinity of the catalytic metal centre. Surface enhanced resonance Raman (SERR) and IR (SEIRA) spectro-electrochemistry has been applied concomitantly for the first time to analyse such iron hangman porphyrin complexes attached to electrodes in aqueous solution. While the SERR spectra yield information about the redox state of the central iron, the SEIRA spectra show protonation and deprotonation events of the 2nd coordination sphere. To investigate the influence of a proton active hanging group on the heterogeneous electron transfer between the iron porphyrin and the electrode, two hangman complexes with either an acid or ester functional group were compared. Using time resolved SERR spectroscopy the electron transfer rates of both complexes were determined. Complexes with an acid group showed a slow electron transfer rate at neutral pH that increased significantly at pH 4, while complexes with an ester group exhibited a much faster, but pH independent rate. SEIRA measurements were able to determine directly for the first time a pKa value of 3.4 of a carboxylic hanging group in the immobilized state that shifted to 5.2 in D2O buffer solution. The kinetic data showed an increase of the heterogeneous electron transfer rate with the protonation degree of the acid groups. From these results, we propose a PCET which is strongly modulated by the protonation state of the acid hanging group via hydrogen bond interactions.
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Affiliation(s)
- H K Ly
- Department of Chemistry , Technische Universität Berlin , PC14, Straße des 17. Juni 135 , D-10623 Berlin , Germany . ;
| | - P Wrzolek
- Department of Chemistry , Humboldt Universität zu Berlin , Brook-Taylor-Str. 2 , D-12489 Berlin , Germany .
| | - N Heidary
- Department of Chemistry , Technische Universität Berlin , PC14, Straße des 17. Juni 135 , D-10623 Berlin , Germany . ;
| | - R Götz
- Department of Chemistry , Technische Universität Berlin , PC14, Straße des 17. Juni 135 , D-10623 Berlin , Germany . ;
| | - M Horch
- Department of Chemistry , Technische Universität Berlin , PC14, Straße des 17. Juni 135 , D-10623 Berlin , Germany . ;
| | - J Kozuch
- Department of Chemistry , Technische Universität Berlin , PC14, Straße des 17. Juni 135 , D-10623 Berlin , Germany . ;
| | - M Schwalbe
- Department of Chemistry , Humboldt Universität zu Berlin , Brook-Taylor-Str. 2 , D-12489 Berlin , Germany .
| | - I M Weidinger
- Department of Chemistry , Technische Universität Berlin , PC14, Straße des 17. Juni 135 , D-10623 Berlin , Germany . ;
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Sharma SK, Rogler PJ, Karlin KD. Reactions of a heme-superoxo complex toward a cuprous chelate and •NO (g): C cO and NOD chemistry. J PORPHYR PHTHALOCYA 2015; 19:352-360. [PMID: 26056423 PMCID: PMC4457333 DOI: 10.1142/s108842461550025x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Following up on the characterization of a new (heme)FeIII-superoxide species formed from the cryogenic oxygenation of a ferrous-heme (PPy)FeII (1) (PPy = a tetraarylporphyrinate with a covalently tethered pyridine group as a potential axial base), giving (PPy)FeIII-O2•- (2) (Li Y et al., Polyhedron 2013; 58: 60-64), we report here on (i) its use in forming a cytochrome c oxidase (CcO) model compound, or (ii) in a reaction with nitrogen monoxide (•NO; nitric oxide) to mimic nitric oxide dioxygenase (NOD) chemistry. Reaction of (2) with the cuprous chelate [CuI(AN)][B(C6F5)4] (AN = bis[3-(dimethylamino) propyl]amine) gives a meta-stable product [(PPy)FeIII-([Formula: see text])-CuII(AN)][B(C6F5)4] (3a), possessing a high-spin iron(III) and Cu(II) side-on bridged peroxo moiety with a μ-η2:η2-binding motif. This complex thermally decays to a corresponding μ-oxo complex [(PPy)FeIII-(O2-)-CuII(AN)][B(C6F5)4] (3). Both (3) and (3a) have been characterized by UV-vis, 2H NMR and EPR spectroscopies. When (2) is exposed to •NO(g), a ferric heme nitrato compound forms; if 2,4-di-tert-butylphenol is added prior to •NO(g) exposure, phenol ortho-nitration occurs with the iron product being the ferric hydroxide complex (PPy) FeIII(OH) (5). The latter reactions mimic the action of NOD's.
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Affiliation(s)
- Savita K. Sharma
- Department of Chemistry, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Patrick J. Rogler
- Department of Chemistry, Johns Hopkins University, Baltimore, MD 21218, USA
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Abstract
In order to address how diverse metalloprotein active sites, in particular those containing iron and copper, guide O₂binding and activation processes to perform diverse functions, studies of synthetic models of the active sites have been performed. These studies have led to deep, fundamental chemical insights into how O₂coordinates to mono- and multinuclear Fe and Cu centers and is reduced to superoxo, peroxo, hydroperoxo, and, after O-O bond scission, oxo species relevant to proposed intermediates in catalysis. Recent advances in understanding the various factors that influence the course of O₂activation by Fe and Cu complexes are surveyed, with an emphasis on evaluating the structure, bonding, and reactivity of intermediates involved. The discussion is guided by an overarching mechanistic paradigm, with differences in detail due to the involvement of disparate metal ions, nuclearities, geometries, and supporting ligands providing a rich tapestry of reaction pathways by which O₂is activated at Fe and Cu sites.
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Schwalbe M, Wrzolek P, Lal G, Braun B. High‐Yielding Synthesis of a Hetero‐Pacman Compound and the Characterization of Intermediates and Side‐Products. Eur J Inorg Chem 2014. [DOI: 10.1002/ejic.201402459] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Matthias Schwalbe
- Institute of Chemistry, Humboldt‐Universität zu Berlin, Brook‐Taylor‐St. 2, 12489 Berlin, Germany, http://www.chemie.hu‐berlin.de/aglimberg/mschwalbe/ index.html
| | - Pierre Wrzolek
- Institute of Chemistry, Humboldt‐Universität zu Berlin, Brook‐Taylor‐St. 2, 12489 Berlin, Germany, http://www.chemie.hu‐berlin.de/aglimberg/mschwalbe/ index.html
| | - Garima Lal
- Institute of Chemistry, Humboldt‐Universität zu Berlin, Brook‐Taylor‐St. 2, 12489 Berlin, Germany, http://www.chemie.hu‐berlin.de/aglimberg/mschwalbe/ index.html
| | - Beatrice Braun
- Institute of Chemistry, Humboldt‐Universität zu Berlin, Brook‐Taylor‐St. 2, 12489 Berlin, Germany, http://www.chemie.hu‐berlin.de/aglimberg/mschwalbe/ index.html
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Li Y, Sharma SK, Karlin KD. New heme-dioxygen and carbon monoxide adducts using pyridyl or imidazolyl tailed porphyrins. Polyhedron 2013; 58. [PMID: 24223452 DOI: 10.1016/j.poly.2012.11.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Inspired by the chemistry relevant to dioxygen storage, transport and activation by metalloproteins, in particular for heme/copper oxidases, and carbon monoxide binding to metal-containing active sites as a probe or surrogate for dioxygen binding, a series of heme derived dioxygen and CO complexes have been designed, synthesized, and characterized with respect to their physical properties and reactivity. The focus of this study is in the description and comparison of three types heme-superoxo and heme-CO adducts. The starting point is in the characterization of the reduced heme complexes, [(F8)FeII], [(PPy)FeII] and [(PIm)FeII], where F8, PPy and PIm are iron(II)-porphyrinates and where PPy and PIm possess a covalently tethered axial base pyridyl or imidazolyl group, respectively. The spin-state properties of these complexes vary with solvent. The low temperature reaction between O2 and these reduced porphyrin FeII complex yield distinctive low spin heme-superoxo adducts. The dioxygen binding properties for all three complexes are shown to be reversible, via alternate argon or O2 bubbling. Carbon monoxide binds to the reduced heme-FeII precursors to form low spin heme-CO adducts. The implications for future investigations of these heme O2 and CO adducts are discussed.
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Affiliation(s)
- Yuqi Li
- Department of Chemistry, The Johns Hopkins University, Baltimore, MD 21218
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14
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Schwalbe M, Metzinger R, Teets TS, Nocera DG. Terpyridine-Porphyrin Hetero-Pacman Compounds. Chemistry 2012; 18:15449-58. [DOI: 10.1002/chem.201201728] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Revised: 08/20/2012] [Indexed: 12/31/2022]
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15
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Hijazi I, Roisnel T, Even-Hernandez P, Geneste F, Cador O, Guizouarn T, Boitrel B. Structural characterization of zinc and iron (II/III) complexes of a porphyrin bearing two built-in nitrogen bases. An example of high-spin diaqua-iron(III) bromo complex. Inorg Chem 2010; 49:7536-44. [PMID: 20690763 DOI: 10.1021/ic1009384] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A bis-strapped porphyrin with two intramolecular nitrogen bases was synthesized, and its zinc(II), iron(II), and iron(III) complexes have been structurally characterized. Whereas the zinc(II) complex is square pyramidal five-coordinate and the iron(II) complex is six-coordinate despite a significant distortion of the macrocycle induced by the rigidity of the straps, the iron(III) complex exhibits a peculiar bis-aqua structure in which no intramolecular axial base is bound to the iron atom in the porphyrin. Furthermore, on one side, the bromide counteranion of the iron is bound inside the cycle formed by a strap and establishes a hydrogen bond with an axially bound water molecule. On the other side, a residual HBr molecule protonates one pyridine base leading to the formation of an intermolecular pyridinium-pyridine hydrogen bond. The large ionic radius of the high-spin iron(III) cation is accommodated in the macrocycle with no displacement of the metal out of the mean porphyrinic plane, with an average Fe-Np bond distance of 2.057 A, and the axial Fe-Ow(aqua) bond distance measured at 2.090 A. As a result, this high-spin iron(III) bis-aqua complex is only lightly distorted.
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Affiliation(s)
- Ismail Hijazi
- Université de Rennes1, Sciences Chimiques de Rennes, UMR CNRS 6226, 35042 Rennes Cedex, France
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Halime Z, Kieber-Emmons MT, Qayyum MF, Mondal B, Gandhi T, Puiu SC, Chufán EE, Sarjeant AAN, Hodgson KO, Hedman B, Solomon EI, Karlin KD. Heme-copper-dioxygen complexes: toward understanding ligand-environmental effects on the coordination geometry, electronic structure, and reactivity. Inorg Chem 2010; 49:3629-45. [PMID: 20380465 PMCID: PMC2893725 DOI: 10.1021/ic9020993] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The nature of the ligand is an important aspect of controlling the structure and reactivity in coordination chemistry. In connection with our study of heme-copper-oxygen reactivity relevant to cytochrome c oxidase dioxygen-reduction chemistry, we compare the molecular and electronic structures of two high-spin heme-peroxo-copper [Fe(III)O(2)(2-)Cu(II)](+) complexes containing N(4) tetradentate (1) or N(3) tridentate (2) copper ligands. Combining previously reported and new resonance Raman and EXAFS data coupled to density functional theory calculations, we report a geometric structure and more complete electronic description of the high-spin heme-peroxo-copper complexes 1 and 2, which establish mu-(O(2)(2-)) side-on to the Fe(III) and end-on to Cu(II) (mu-eta(2):eta(1)) binding for the complex 1 but side-on/side-on (mu-eta(2):eta(2)) mu-peroxo coordination for the complex 2. We also compare and summarize the differences and similarities of these two complexes in their reactivity toward CO, PPh(3), acid, and phenols. The comparison of a new X-ray structure of mu-oxo complex 2a with the previously reported 1a X-ray structure, two thermal decomposition products respectively of 2 and 1, reveals a considerable difference in the Fe-O-Cu angle between the two mu-oxo complexes ( angleFe-O-Cu = 178.2 degrees in 1a and angleFe-O-Cu = 149.5 degrees in 2a). The reaction of 2 with 1 equiv of an exogenous nitrogen-donor axial base leads to the formation of a distinctive low-temperature-stable, low-spin heme-dioxygen-copper complex (2b), but under the same conditions, the addition of an axial base to 1 leads to the dissociation of the heme-peroxo-copper assembly and the release of O(2). 2b reacts with phenols performing H-atom (e(-) + H(+)) abstraction resulting in O-O bond cleavage and the formation of high-valent ferryl [Fe(IV)=O] complex (2c). The nature of 2c was confirmed by a comparison of its spectroscopic features and reactivity with those of an independently prepared ferryl complex. The phenoxyl radical generated by the H-atom abstraction was either (1) directly detected by electron paramagnetic resonance spectroscopy using phenols that produce stable radicals or (2) indirectly detected by the coupling product of two phenoxyl radicals.
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Affiliation(s)
- Zakaria Halime
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, USA
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Jelinek R, Silbert L. Biomimetic approaches for studying membrane processes. MOLECULAR BIOSYSTEMS 2009; 5:811-8. [PMID: 19603114 DOI: 10.1039/b907223n] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This short review focuses on recent innovative systems and experimental approaches designed to investigate membrane processes and biomolecular interactions associated with membranes. Our emphasis is on "biomimetics" which reflects the significance and contributions of the chemistry/biology interface in addressing complex biological questions. We have not limited this review to discussion of new "sensors" or "assays"per se, but rather we tried to review new concepts employed for analysis of membrane processes.
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Affiliation(s)
- Raz Jelinek
- Department of Chemistry, Ben Gurion University of the Negev, Beer Sheva 84105, Israel.
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Toma HE, Araki K. Exploring the Supramolecular Coordination Chemistry-Based Approach for Nanotechnology. ACTA ACUST UNITED AC 2009. [DOI: 10.1002/9780470440124.ch5] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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Collman JP, Decréau RA. Functional biomimetic models for the active site in the respiratory enzyme cytochrome c oxidase. Chem Commun (Camb) 2008:5065-76. [PMID: 18956030 DOI: 10.1039/b808070b] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A functional analog of the active site in the respiratory enzyme, cytochrome c oxidase (CcO) reproduces every feature in CcO's active site: a myoglobin-like heme (heme a3), a distal tridentate imidazole copper complex (Cu(B)), a phenol (Tyr244), and a proximal imidazole. When covalently attached to a liquid-crystalline SAM film on an Au electrode, this functional model continuously catalyzes the selective four-electron reduction of dioxygen at physiological potential and pH, under rate-limiting electron flux (as occurs in CcO).
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Affiliation(s)
- James P Collman
- Stanford University, Chemistry Department, Stanford, CA-94305-5080, USA.
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Ruzié C, Even-Hernandez P, Boitrel B. Efficient and Versatile Synthesis of New Porphyrins Bearing an N3O Moiety: Ligands for Mimicking Cytochrome c Oxidase. Org Lett 2008; 10:2673-6. [DOI: 10.1021/ol800731t] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Christian Ruzié
- Université de Rennes1, Sciences Chimiques de Rennes, Ingénierie Chimique et Molécules du Vivant, UMR CNRS 6226, 35042 Rennes Cedex, France
| | - Pascale Even-Hernandez
- Université de Rennes1, Sciences Chimiques de Rennes, Ingénierie Chimique et Molécules du Vivant, UMR CNRS 6226, 35042 Rennes Cedex, France
| | - Bernard Boitrel
- Université de Rennes1, Sciences Chimiques de Rennes, Ingénierie Chimique et Molécules du Vivant, UMR CNRS 6226, 35042 Rennes Cedex, France
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Intermolecular versus intramolecular electron-/atom- (Cl) transfer in heme-iron and copper pyridylalkylamine complexes. Inorganica Chim Acta 2008. [DOI: 10.1016/j.ica.2007.08.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Guerra KP, Delgado R. Homo-and heterodinuclear complexes of the tris(catecholamide) derivative of a tetraazamacrocycle with Fe3+, Cu2+and Zn2+metal ions. Dalton Trans 2008:539-50. [DOI: 10.1039/b712916e] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Liu JG, Naruta Y, Tani F. Synthetic Models of the Active Site of Cytochromec Oxidase: Influence of Tridentate or Tetradentate Copper Chelates Bearing a HisTyr Linkage Mimic on Dioxygen Adduct Formation by Heme/Cu Complexes. Chemistry 2007; 13:6365-78. [PMID: 17503416 DOI: 10.1002/chem.200601884] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Two synthetic models of the active site of cytochrome c oxidase--[(LN4-OH)CuI-FeII(TMP)]+ (1 a) and [(LN3-OH)CuI-FeII(TMP)]+ (2 a)-have been designed and synthesized. These models each contain a heme and a covalently attached copper moiety supported either by a tetradentate N4-copper chelate or by a tridentate N3-copper chelate including a moiety that acts as a mimic of the crosslinked His-Tyr component of cytochrome c oxidase. Low-temperature oxygenation reactions of these models have been investigated by spectroscopic methods including UV/Vis, resonance Raman, ESI-MS, and EPR spectroscopy. Oxygenation of the tetradentate model 1 a in MeCN and in other solvents produces a low-temperature-stable dioxygen-bridged peroxide [(LN4-OH)CuII-O2-FeIII(TMP)]+ {nuO--O=799 (16O2)/752 cm(-1) (18O2)}, while a heme superoxide species [(TMP)FeIII(O2-)CuIILN3-OH] {nuFe--O2: 576 (16O2)/551 cm(-1) (18O2)} is generated when the tridentate model 2 a is oxygenated in EtCN solution under similar experimental conditions. The coexistence of a heme superoxide species [(TMP)FeIII(O2-)CuIILN3-OH] and a bridged peroxide [(LN3-OH)CuII-O2-FeIII(TMP)]+ species in equal amounts is observed when the oxygenation reaction of 2 a is performed in CH2Cl(2)/7 % EtCN, while the percentage of the peroxide (approximately 70 %) in relation to superoxide (approximately 30 %) increases further when the crosslinked phenol moiety in 2 a is deprotonated to produce the bridged peroxide [(LN3-OH)CuII-O2-FeIII(TMP)]+ {nuO--O: 812 (16O2)/765 cm(-1) (18O2)} as the main dioxygen intermediate. The weak reducibility and decreased O2 reactivity of the tricoordinated CuI site in 2 a are responsible for the solvent-dependent formation of dioxygen adducts. The initial binding of dioxygen to the copper site en route to the formation of a bridged heme-O2-Cu intermediate by model 2 a is suggested and the deprotonated crosslinked His-Tyr moiety might contribute to enhancement of the O2 affinity of the CuI site at an early stage of the dioxygen-binding process.
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Affiliation(s)
- Jin-Gang Liu
- Institute for Materials Chemistry and Engineering, Kyushu University, Higashi-ku, Fukuoka, 812-8581, Japan
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Chufán EE, Puiu SC, Karlin KD. Heme-copper/dioxygen adduct formation, properties, and reactivity. Acc Chem Res 2007; 40:563-72. [PMID: 17550225 DOI: 10.1021/ar700031t] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This Account focuses on our recent developments in synthetic heme/copper/O 2 chemistry, potentially relevant to the mechanism of action of heme-copper oxidases (e.g., cytochrome c oxidase) and to dioxygen activation chemistry. Methods for the generation of O 2 adducts, which are high-spin heme(Fe (III))-peroxo-Cu (II) complexes, are described, along with a detailed structural/electronic characterization of one example. The coordination mode of the O 2-derived heme-Cu bridging group depends upon the copper-ligand environment, resulting in micro-(O 2 (2-)) side-on to Fe (III) and end-on to Cu (II) (micro-eta (2):eta (1)) binding for cases having N 4 tetradentate ligands but side-on/side-on (micro-eta (2):eta (2)) micro-peroxo coordination with tridentate copper chelates. The dynamics of the generation of Fe (III)-(O 2 (2-))-Cu (II) complexes are known in some cases, including the initial formation of a short-lived superoxo (heme)Fe (III)(O 2 -) intermediate. Complexes with cross-linked imidazole-phenol "cofactors" adjacent to the copper centers have also been described. Essential investigations of heme-copper-mediated reductive O-O bond cleavage chemistry are ongoing.
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Affiliation(s)
- Eduardo E Chufán
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, USA
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Collman JP, Decréau RA, Sunderland CJ. Single-turnover intermolecular reaction between a Feiii–superoxide–Cuicytochrome c oxidase model and exogeneous Tyr244 mimics. Chem Commun (Camb) 2006:3894-6. [PMID: 17268662 DOI: 10.1039/b607277a] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An Fe(III)-superoxide-Cu(I) cytochrome c oxidase model reacts intermolecularly with hindered phenols leading to phenoxyl radicals, as was observed in the enzyme and evidence for the formation of an Fe(IV)-oxo is presented.
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Affiliation(s)
- James P Collman
- Stanford University, Chemistry Department, Stauffer II, Stanford, CA-94306, USA.
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