1
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Blomberg MRA, Ädelroth P. Reduction of molecular oxygen in flavodiiron proteins - Catalytic mechanism and comparison to heme-copper oxidases. J Inorg Biochem 2024; 255:112534. [PMID: 38552360 DOI: 10.1016/j.jinorgbio.2024.112534] [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: 12/27/2023] [Revised: 03/15/2024] [Accepted: 03/18/2024] [Indexed: 04/16/2024]
Abstract
The family of flavodiiron proteins (FDPs) plays an important role in the scavenging and detoxification of both molecular oxygen and nitric oxide. Using electrons from a flavin mononucleotide cofactor molecular oxygen is reduced to water and nitric oxide is reduced to nitrous oxide and water. While the mechanism for NO reduction in FDPs has been studied extensively, there is very little information available about O2 reduction. Here we use hybrid density functional theory (DFT) to study the mechanism for O2 reduction in FDPs. An important finding is that a proton coupled reduction is needed after the O2 molecule has bound to the diferrous diiron active site and before the OO bond can be cleaved. This is in contrast to the mechanism for NO reduction, where both NN bond formation and NO bond cleavage occurs from the same starting structure without any further reduction, according to both experimental and computational results. This computational result for the O2 reduction mechanism should be possible to evaluate experimentally. Another difference between the two substrates is that the actual OO bond cleavage barrier is low, and not involved in rate-limiting the reduction process, while the barrier connected with bond cleavage/formation in the NO reduction process is of similar height as the rate-limiting steps. We suggest that these results may be part of the explanation for the generally higher activity for O2 reduction as compared to NO reduction in most FDPs. Comparisons are also made to the O2 reduction reaction in the family of heme‑copper oxidases.
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Affiliation(s)
- Margareta R A Blomberg
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden.
| | - Pia Ädelroth
- Department of Biochemistry and Biophysics, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
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2
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York NJ, Lockart MM, Schmittou AN, Pierce BS. Cyanide replaces substrate in obligate-ordered addition of nitric oxide to the non-heme mononuclear iron AvMDO active site. J Biol Inorg Chem 2023; 28:285-299. [PMID: 36809458 PMCID: PMC10075186 DOI: 10.1007/s00775-023-01990-7] [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: 10/13/2022] [Accepted: 01/12/2023] [Indexed: 02/23/2023]
Abstract
Thiol dioxygenases are a subset of non-heme mononuclear iron oxygenases that catalyze the O2-dependent oxidation of thiol-bearing substrates to yield sulfinic acid products. Cysteine dioxygenase (CDO) and 3-mercaptopropionic acid (3MPA) dioxygenase (MDO) are the most extensively characterized members of this enzyme family. As with many non-heme mononuclear iron oxidase/oxygenases, CDO and MDO exhibit an obligate-ordered addition of organic substrate before dioxygen. As this substrate-gated O2-reactivity extends to the oxygen-surrogate, nitric oxide (NO), EPR spectroscopy has long been used to interrogate the [substrate:NO:enzyme] ternary complex. In principle, these studies can be extrapolated to provide information about transient iron-oxo intermediates produced during catalytic turnover with dioxygen. In this work, we demonstrate that cyanide mimics the native thiol-substrate in ordered-addition experiments with MDO cloned from Azotobacter vinelandii (AvMDO). Following treatment of the catalytically active Fe(II)-AvMDO with excess cyanide, addition of NO yields a low-spin (S = 1/2) (CN/NO)-Fe-complex. Continuous wave and pulsed X-band EPR characterization of this complex produced in wild-type and H157N variant AvMDO reveal multiple nuclear hyperfine features diagnostic of interactions within the first- and outer-coordination sphere of the enzymatic Fe-site. Spectroscopically validated computational models indicate simultaneous coordination of two cyanide ligands replaces the bidentate (thiol and carboxylate) coordination of 3MPA allowing for NO-binding at the catalytically relevant O2-binding site. This promiscuous substrate-gated reactivity of AvMDO with NO provides an instructive counterpoint to the high substrate-specificity exhibited by mammalian CDO for L-cysteine.
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Affiliation(s)
- Nicholas J York
- Department of Chemistry and Biochemistry, University of Alabama, 250 Hackberry Lane, Tuscaloosa, AL, 35487, USA
| | - Molly M Lockart
- Department of Chemistry and Biochemistry, Samford University, 800 Lakeshore Drive, Homewood, AL, 35229, USA
| | - Allison N Schmittou
- Department of Chemistry and Biochemistry, University of Alabama, 250 Hackberry Lane, Tuscaloosa, AL, 35487, USA
| | - Brad S Pierce
- Department of Chemistry and Biochemistry, University of Alabama, 250 Hackberry Lane, Tuscaloosa, AL, 35487, USA.
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3
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Blomberg MRA, Ädelroth P. Reduction of Nitric Oxide to Nitrous Oxide in Flavodiiron Proteins: Catalytic Mechanism and Plausible Intermediates. ACS Catal 2023. [DOI: 10.1021/acscatal.2c04932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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4
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Tao W, Carter S, Trevino R, Zhang W, Shafaat HS, Zhang S. Reductive NO Coupling at Dicopper Center via a [Cu 2(NO) 2] 2+ Diamond-Core Intermediate. J Am Chem Soc 2022; 144:22633-22640. [PMID: 36469729 DOI: 10.1021/jacs.2c09523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Treatment of a dicopper(I,I) complex with excess amounts of NO leads to the formation of a dicopper dinitrosyl [Cu2(NO)2]2+ complex capable of (i) releasing two equivalents of NO reversibly in 90% yield and (ii) reacting with another equivalent of NO to afford N2O and dicopper nitrosyl oxo species [Cu2(NO)(O)]2+. Resonance Raman characterization of the [Cu2(NO)2]2+ complex shows a 15N-sensitive N═O stretch at 1527.6 cm-1 and two Cu-N stretches at 390.6 and 414.1 cm-1, supporting a symmetric diamond-core structure with bis-μ-NO ligands. The conversion of [Cu2(NO)2]2+ to [Cu2(NO)O]2+ occurs via a rate-limiting reaction with NO and bypasses the dicopper oxo intermediate, a mechanism distinct from that of diFe-mediated NO reduction to N2O.
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Affiliation(s)
- Wenjie Tao
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Samantha Carter
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Regina Trevino
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Weiyao Zhang
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Hannah S Shafaat
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Shiyu Zhang
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
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5
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Transue WJ, Snyder RA, Caranto JD, Kurtz DM, Solomon EI. Particle Swarm Fitting of Spin Hamiltonians: Magnetic Circular Dichroism of Reduced and NO-Bound Flavodiiron Protein. Inorg Chem 2022; 61:16520-16527. [PMID: 36223761 PMCID: PMC9942269 DOI: 10.1021/acs.inorgchem.2c02234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A particle swarm optimization (PSO) algorithm is described for the fitting of ground-state spin Hamiltonian parameters from variable-temperature/variable-field (VTVH) magnetic circular dichroism (MCD) data. This PSO algorithm is employed to define the ground state of two catalytic intermediates from a flavodiiron protein (FDP), a class of enzymes with nitric oxide reductase activity. The bimetallic iron active site of this enzyme proceeds through a biferrous intermediate and a mixed ferrous-{FeNO}7 intermediate during the catalytic cycle, and the MCD spectra of these intermediates are presented and analyzed. The fits of the spin Hamiltonians are shown to provide important geometric and electronic insight into these species that is compared and contrasted with previous reports.
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Affiliation(s)
| | - Rae Ana Snyder
- Department of Chemistry, Stanford University, Stanford, CA 94305
| | - Jonathan D. Caranto
- Department of Chemistry, University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Donald M. Kurtz
- Department of Chemistry, University of Texas at San Antonio, San Antonio, Texas 78249, United States
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6
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White CJ, Lengel MO, Bracken AJ, Kampf JW, Speelman AL, Alp EE, Hu MY, Zhao J, Lehnert N. Distortion of the [FeNO] 2 Core in Flavodiiron Nitric Oxide Reductase Models Inhibits N-N Bond Formation and Promotes Formation of Unusual Dinitrosyl Iron Complexes: Implications for Catalysis and Reactivity. J Am Chem Soc 2022; 144:3804-3820. [PMID: 35212523 DOI: 10.1021/jacs.1c10388] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Flavodiiron nitric oxide reductases (FNORs) carry out the reduction of nitric oxide (NO) to nitrous oxide (N2O), allowing infectious pathogens to mitigate toxic levels of NO generated in the human immune response. We previously reported the model complex [Fe2(BPMP)(OPr)(NO)2](OTf)2 (1, OPr- = propionate) that contains two coplanar NO ligands and that is capable of quantitative NO reduction to N2O [White et al. J. Am. Chem. Soc. 2018, 140, 2562-2574]. Here we investigate, for the first time, how a distortion of the active site affects the ability of the diiron core to mediate N2O formation. For this purpose, we prepared several analogues of 1 that contain two monodentate ligands in place of the bridging carboxylate, [Fe2(BPMP)(X)2(NO)2]3+/1+ (2-X; X = triflate, 1-methylimidazole, or methanol). Structural data of 2-X show that without the bridging carboxylate, the diiron core expands, leading to elongated (O)N-N(O) distances (from 2.80 Å in 1 to 3.00-3.96 Å in 2-X) and distorted (O)N-Fe-Fe-N(O) dihedral angles (from coplanarity (5.9°) in 1 to 52.9-85.1° in 2-X). Whereas 1 produces quantitative amounts of N2O upon one-electron reduction, N2O production is substantially impeded in 2-X, to an initial 5-10% N2O yield. The main products after reduction are unprecedented hs-FeII/{Fe(NO)2}9/10 dinitrosyl iron complexes (DNICs). Even though mononuclear DNICs are stable and do not show N-N coupling (since it is a spin-forbidden process), the hs-FeII/{Fe(NO)2}9/10 DNICs obtained from 2-X show unexpected reactivity and produce up to quantitative N2O yields after 2 h. The implications of these results for the active site structure of FNORs are discussed.
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Affiliation(s)
- Corey J White
- Department of Chemistry, The University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Michael O Lengel
- Department of Chemistry, The University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Abigail J Bracken
- Department of Chemistry, The University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Jeff W Kampf
- Department of Chemistry, The University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Amy L Speelman
- Department of Chemistry, The University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - E Ercan Alp
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Michael Y Hu
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Jiyong Zhao
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Nicolai Lehnert
- Department of Chemistry, The University of Michigan, Ann Arbor, Michigan 48109-1055, United States
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7
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Song X, Liu J, Wang B. Emergence of Function from Nonheme Diiron Oxygenases: A Quantum Mechanical/Molecular Mechanical Study of Oxygen Activation and Organophosphonate Catabolism Mechanisms by PhnZ. ACS Catal 2022. [DOI: 10.1021/acscatal.1c05116] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Xitong Song
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Jia Liu
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Binju Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
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8
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Sun XX, Du J, Tan JJ, Zhan SZ. A mono-oxo-bridged binuclear iron(iii) complex with a Fe–O–Fe angle of 180.0° and its catalytic activity for hydrogen evolution. NEW J CHEM 2022. [DOI: 10.1039/d1nj05904a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
There are potential applications for binuclear oxo-bridged iron complexes in biological processes, catalysts, and magnetic materials, and the design of new bridged-iron complexes is important.
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Affiliation(s)
- Xia-Xing Sun
- College of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China
| | - Juan Du
- College of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China
| | - Jie-Jie Tan
- College of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China
| | - Shu-Zhong Zhan
- College of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China
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9
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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: 82] [Impact Index Per Article: 27.3] [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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10
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York NJ, Lockart MM, Pierce BS. Low-Spin Cyanide Complexes of 3-Mercaptopropionic Acid Dioxygenase (MDO) Reveal the Impact of Outer-Sphere SHY-Motif Residues. Inorg Chem 2021; 60:18639-18651. [PMID: 34883020 PMCID: PMC10078988 DOI: 10.1021/acs.inorgchem.1c01519] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
3-Mercaptopropionic acid (3MPA) dioxygenase (MDO) is a non-heme Fe(II)/O2-dependent oxygenase that catalyzes the oxidation of thiol-substrates to yield the corresponding sulfinic acid. Hydrogen-bonding interactions between the Fe-site and a conserved set of three outer-sphere residues (Ser-His-Tyr) play an important catalytic role in the mechanism of this enzyme. Collectively referred to as the SHY-motif, the functional role of these residues remains poorly understood. Here, catalytically inactive Fe(III)-MDO precomplexed with 3MPA was titrated with cyanide to yield a low-spin (S = 1/2) (3MPA/CN)-bound ternary complex (referred to as 1C). UV-visible and electron paramagnetic resonance (EPR) spectroscopy were used to monitor the binding of 3MPA and cyanide. Comparisons of results obtained from SHY-motif variants (H157N and Y159F) were performed to investigate specific H-bonding interactions. For the wild-type enzyme, the binding of 3MPA- and cyanide to the enzymatic Fe-site is selective and results in a homogeneous ternary complex. However, this selectivity is lost for the Y159F variant, suggesting that H-bonding interactions contributed from Tyr159 gate ligand coordination at the Fe-site. Significantly, the g-values for the low-spin ferric site are diagnostic of the directionality of Tyr159 H-bond donation. Computational models coupled with CASSCF/NEVPT2-calculated g-values were used to verify that a major shift in the central g-value (g2) displayed between wild-type and SHY variants could be attributed to the loss of Tyr159 H-bond donation to the Fe-bound cyanide. Applied to native cosubstrate, this H-bond donation provides a means to stabilize Fe-bound dioxygen and potentially explains the attenuated (∼15-fold) rate of catalytic turnover previously reported for MDO SHY-motif variants.
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Affiliation(s)
- Nicholas J York
- Department of Chemistry & Biochemistry, University of Alabama, 250 Hackberry Lane, Tuscaloosa, Alabama 35487, United States
| | - Molly M Lockart
- Department of Chemistry & Biochemistry, University of Alabama, 250 Hackberry Lane, Tuscaloosa, Alabama 35487, United States
| | - Brad S Pierce
- Department of Chemistry & Biochemistry, University of Alabama, 250 Hackberry Lane, Tuscaloosa, Alabama 35487, United States
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11
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Kamnev AA, Tugarova AV. Bioanalytical applications of Mössbauer spectroscopy. RUSSIAN CHEMICAL REVIEWS 2021. [DOI: 10.1070/rcr5006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Abstract
Data on the applications of Mössbauer spectroscopy in the transmission (mainly on 57Fe nuclei) and emission (on 57Co nuclei) variants for analytical studies at the molecular level of metal-containing components in a wide range of biological objects (from biocomplexes and biomacromolecules to supramolecular structures, cells, tissues and organisms) and of objects that are participants or products of biological processes, published in the last 15 years are discussed and systematized. The prospects of the technique in its biological applications, including the developing fields (emission variant, use of synchrotron radiation), are formulated.
The bibliography includes 248 references.
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12
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Synergistic DFT-guided design and microfluidic synthesis of high-performance ion-imprinted biosorbents for selective heavy metal removal. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2021.127030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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13
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Dey A, Gordon JB, Albert T, Sabuncu S, Siegler MA, MacMillan SN, Lancaster KM, Moënne‐Loccoz P, Goldberg DP. A Nonheme Mononuclear {FeNO}
7
Complex that Produces N
2
O in the Absence of an Exogenous Reductant. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202109062] [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)
- Aniruddha Dey
- Department of Chemistry The Johns Hopkins University Baltimore MD 21218 USA
| | - Jesse B. Gordon
- Department of Chemistry The Johns Hopkins University Baltimore MD 21218 USA
| | - Therese Albert
- Department of Chemical Physiology and Biochemistry Oregon Health & Science University Portland OR 97239 USA
| | - Sinan Sabuncu
- Department of Chemical Physiology and Biochemistry Oregon Health & Science University Portland OR 97239 USA
| | - Maxime A. Siegler
- Department of Chemistry The Johns Hopkins University Baltimore MD 21218 USA
| | | | - Kyle M. Lancaster
- Department of Chemistry and Chemical Biology Cornell University Ithaca NY 14853 USA
| | - Pierre Moënne‐Loccoz
- Department of Chemical Physiology and Biochemistry Oregon Health & Science University Portland OR 97239 USA
| | - David P. Goldberg
- Department of Chemistry The Johns Hopkins University Baltimore MD 21218 USA
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14
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Dey A, Gordon JB, Albert T, Sabuncu S, Siegler MA, MacMillan SN, Lancaster KM, Moënne-Loccoz P, Goldberg DP. A Nonheme Mononuclear {FeNO} 7 Complex that Produces N 2 O in the Absence of an Exogenous Reductant. Angew Chem Int Ed Engl 2021; 60:21558-21564. [PMID: 34415659 DOI: 10.1002/anie.202109062] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Indexed: 11/09/2022]
Abstract
A new nonheme iron(II) complex, FeII (Me3 TACN)((OSiPh2 )2 O) (1), is reported. Reaction of 1 with NO(g) gives a stable mononitrosyl complex Fe(NO)(Me3 TACN)((OSiPh2 )2 O) (2), which was characterized by Mössbauer (δ=0.52 mm s-1 , |ΔEQ |=0.80 mm s-1 ), EPR (S=3/2), resonance Raman (RR) and Fe K-edge X-ray absorption spectroscopies. The data show that 2 is an {FeNO}7 complex with an S=3/2 spin ground state. The RR spectrum (λexc =458 nm) of 2 combined with isotopic labeling (15 N, 18 O) reveals ν(N-O)=1680 cm-1 , which is highly activated, and is a nearly identical match to that seen for the reactive mononitrosyl intermediate in the nonheme iron enzyme FDPnor (ν(NO)=1681 cm-1 ). Complex 2 reacts rapidly with H2 O in THF to produce the N-N coupled product N2 O, providing the first example of a mononuclear nonheme iron complex that is capable of converting NO to N2 O in the absence of an exogenous reductant.
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Affiliation(s)
- Aniruddha Dey
- Department of Chemistry, The Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Jesse B Gordon
- Department of Chemistry, The Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Therese Albert
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Sinan Sabuncu
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Maxime A Siegler
- Department of Chemistry, The Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Samantha N MacMillan
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - Kyle M Lancaster
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - Pierre Moënne-Loccoz
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, 97239, USA
| | - David P Goldberg
- Department of Chemistry, The Johns Hopkins University, Baltimore, MD, 21218, USA
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15
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The Amino Acids Motif -32GSSYN36- in the Catalytic Domain of E. coli Flavorubredoxin NO Reductase Is Essential for Its Activity. Catalysts 2021. [DOI: 10.3390/catal11080926] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Flavodiiron proteins (FDPs) are a family of modular and soluble enzymes endowed with nitric oxide and/or oxygen reductase activities, producing N2O or H2O, respectively. The FDP from Escherichia coli, which, apart from the two core domains, possesses a rubredoxin-like domain at the C-terminus (therefore named flavorubredoxin (FlRd)), is a bona fide NO reductase, exhibiting O2 reducing activity that is approximately ten times lower than that for NO. Among the flavorubredoxins, there is a strictly conserved amino acids motif, -G[S,T]SYN-, close to the catalytic diiron center. To assess its role in FlRd’s activity, we designed several site-directed mutants, replacing the conserved residues with hydrophobic or anionic ones. The mutants, which maintained the general characteristics of the wild type enzyme, including cofactor content and integrity of the diiron center, revealed a decrease of their oxygen reductase activity, while the NO reductase activity—specifically, its physiological function—was almost completely abolished in some of the mutants. Molecular modeling of the mutant proteins pointed to subtle changes in the predicted structures that resulted in the reduction of the hydration of the regions around the conserved residues, as well as in the elimination of hydrogen bonds, which may affect proton transfer and/or product release.
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16
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Miller KR, Biswas S, Jasniewski A, Follmer AH, Biswas A, Albert T, Sabuncu S, Bominaar EL, Hendrich MP, Moënne-Loccoz P, Borovik AS. Artificial Metalloproteins with Dinuclear Iron-Hydroxido Centers. J Am Chem Soc 2021; 143:2384-2393. [PMID: 33528256 DOI: 10.1021/jacs.0c12564] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Dinuclear iron centers with a bridging hydroxido or oxido ligand form active sites within a variety of metalloproteins. A key feature of these sites is the ability of the protein to control the structures around the Fe centers, which leads to entatic states that are essential for function. To simulate this controlled environment, artificial proteins have been engineered using biotin-streptavidin (Sav) technology in which Fe complexes from adjacent subunits can assemble to form [FeIII-(μ-OH)-FeIII] cores. The assembly process is promoted by the site-specific localization of the Fe complexes within a subunit through the designed mutation of a tyrosinate side chain to coordinate the Fe centers. An important outcome is that the Sav host can regulate the Fe···Fe separation, which is known to be important for function in natural metalloproteins. Spectroscopic and structural studies from X-ray diffraction methods revealed uncommonly long Fe···Fe separations that change by less than 0.3 Å upon the binding of additional bridging ligands. The structural constraints imposed by the protein host on the di-Fe cores are unique and create examples of active sites having entatic states within engineered artificial metalloproteins.
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Affiliation(s)
- Kelsey R Miller
- Department of Chemistry, 1102 Natural Sciences II, University of California, Irvine, California 92697, United States
| | - Saborni Biswas
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Andrew Jasniewski
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697, United States
| | - Alec H Follmer
- Department of Chemistry, 1102 Natural Sciences II, University of California, Irvine, California 92697, United States
| | - Ankita Biswas
- Department of Chemistry, 1102 Natural Sciences II, University of California, Irvine, California 92697, United States
| | - Therese Albert
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Mail Code HRC3, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, United States
| | - Sinan Sabuncu
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Mail Code HRC3, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, United States
| | - Emile L Bominaar
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Michael P Hendrich
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Pierre Moënne-Loccoz
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Mail Code HRC3, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, United States
| | - A S Borovik
- Department of Chemistry, 1102 Natural Sciences II, University of California, Irvine, California 92697, United States
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17
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Biswas S, Kurtz DM, Montoya SR, Hendrich MP, Bominaar EL. The Catalytic Role of a Conserved Tyrosine in Nitric Oxide-Reducing Non-heme Diiron Enzymes. ACS Catal 2020. [DOI: 10.1021/acscatal.0c01884] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Saborni Biswas
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Donald M. Kurtz
- Department of Chemistry, University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Samuel R. Montoya
- Department of Chemistry, University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Michael P. Hendrich
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Emile L. Bominaar
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
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18
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Ferousi C, Majer SH, DiMucci IM, Lancaster KM. Biological and Bioinspired Inorganic N-N Bond-Forming Reactions. Chem Rev 2020; 120:5252-5307. [PMID: 32108471 PMCID: PMC7339862 DOI: 10.1021/acs.chemrev.9b00629] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The metallobiochemistry underlying the formation of the inorganic N-N-bond-containing molecules nitrous oxide (N2O), dinitrogen (N2), and hydrazine (N2H4) is essential to the lifestyles of diverse organisms. Similar reactions hold promise as means to use N-based fuels as alternative carbon-free energy sources. This review discusses research efforts to understand the mechanisms underlying biological N-N bond formation in primary metabolism and how the associated reactions are tied to energy transduction and organismal survival. These efforts comprise studies of both natural and engineered metalloenzymes as well as synthetic model complexes.
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Affiliation(s)
- Christina Ferousi
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Sean H Majer
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Ida M DiMucci
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Kyle M Lancaster
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
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19
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Lai W, Zhang K, Shao P, Yang L, Ding L, Pavlostathis SG, Shi H, Zou L, Liang D, Luo X. Optimization of adsorption configuration by DFT calculation for design of adsorbent: A case study of palladium ion-imprinted polymers. JOURNAL OF HAZARDOUS MATERIALS 2019; 379:120791. [PMID: 31238216 DOI: 10.1016/j.jhazmat.2019.120791] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 06/12/2019] [Accepted: 06/17/2019] [Indexed: 06/09/2023]
Abstract
Trial-and-error method is widely used to seek an efficient adsorbent, although it is time- and money-consuming. Rationally design of functional materials via theoretical calculation is an emerging and appealing strategy in material science. However, exploiting of theoretical calculation for assistance of adsorbent design is rarely to be attempted despite it is usually utilized to explore the adsorption mechanism. In this work, density functional theory (DFT) calculation is exploited to design an adsorbent with high adsorption capacity and selectivity. The well-known palladium ion-imprinted polymer (IIP) was used as a model adsorbent. Then, three types of given adsorption configurations (a-Pd-IIP, b-Pd-IIP and c-Pd-IIP) were optimized. Further, their adsorption energies were calculated by DFT, which were -13.978 eV for b-Pd-IIP, -8.764 eV for a-Pd-IIP and -3.587 eV for c-Pd-IIP, respectively. The correlation coefficient (R2) between the theoretical adsorption energy and the experimental adsorption capacity reached to as high as 0.985. In addition, the dynamics and selectivity experimental results further consolidated the tendency of the calculation result. All these results demonstrate that the adsorption energy derived from DFT calculations is an important factor in guiding the design of IIPs.
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Affiliation(s)
- Weiqiang Lai
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Kai Zhang
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, PR China; School of Space and Environment, Beihang University, Beijing 100191, PR China
| | - Penghui Shao
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Liming Yang
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, PR China.
| | - Lin Ding
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, PR China; School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, PR China
| | - Spyros G Pavlostathis
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0512, United States
| | - Hui Shi
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Liezhao Zou
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Dahao Liang
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, PR China
| | - Xubiao Luo
- Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, PR China.
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20
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Lehnert N, Fujisawa K, Camarena S, Dong HT, White CJ. Activation of Non-Heme Iron-Nitrosyl Complexes: Turning Up the Heat. ACS Catal 2019. [DOI: 10.1021/acscatal.9b03219] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Nicolai Lehnert
- Department of Chemistry and Department of Biophysics, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109-1055, United States
| | - Kiyoshi Fujisawa
- Department of Chemistry, Ibaraki University, Mito 310-8512, Japan
| | - Stephanie Camarena
- Department of Chemistry and Department of Biophysics, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109-1055, United States
| | - Hai T. Dong
- Department of Chemistry and Department of Biophysics, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109-1055, United States
| | - Corey J. White
- Department of Chemistry and Department of Biophysics, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109-1055, United States
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21
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Folgosa F, Martins MC, Teixeira M. Diversity and complexity of flavodiiron NO/O2 reductases. FEMS Microbiol Lett 2019; 365:4733271. [PMID: 29240952 DOI: 10.1093/femsle/fnx267] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 12/11/2017] [Indexed: 11/14/2022] Open
Abstract
Flavodiiron proteins (FDPs) are a family of enzymes endowed with nitric oxide (NO) or oxygen reductase activities, forming the innocuous nitrous oxide (N2O) or water molecules, respectively. FDPs are widespread in the three life kingdoms, and have a modular nature, being each monomer minimally constituted by a metallo-β-lactamase-like domain containing a catalytic diiron centre, followed by a flavodoxin one, with a flavin mononucleotide. Since their discovery, additional domains have been found in FDPs, attached to the C-terminus, and containing either extra metal (iron) centers or extra flavin binding modules. Following an extensive analysis of genomic databases, we identified novel domain compositions, and proposed a new classification of FDPs in eight classes based on the nature and number of extra domains.
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22
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Martins MC, Romão CV, Folgosa F, Borges PT, Frazão C, Teixeira M. How superoxide reductases and flavodiiron proteins combat oxidative stress in anaerobes. Free Radic Biol Med 2019; 140:36-60. [PMID: 30735841 DOI: 10.1016/j.freeradbiomed.2019.01.051] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 01/14/2019] [Accepted: 01/31/2019] [Indexed: 12/31/2022]
Abstract
Microbial anaerobes are exposed in the natural environment and in their hosts, even if transiently, to fluctuating concentrations of oxygen and its derived reactive species, which pose a considerable threat to their anoxygenic lifestyle. To counteract these stressful conditions, they contain a multifaceted array of detoxifying systems that, in conjugation with cellular repairing mechanisms and in close crosstalk with metal homeostasis, allow them to survive in the presence of O2 and reactive oxygen species. Some of these systems are shared with aerobes, but two families of enzymes emerged more recently that, although not restricted to anaerobes, are predominant in anaerobic microbes. These are the iron-containing superoxide reductases, and the flavodiiron proteins, endowed with O2 and/or NO reductase activities, which are the subject of this Review. A detailed account of their physicochemical, physiological and molecular mechanisms will be presented, highlighting their unique properties in allowing survival of anaerobes in oxidative stress conditions, and comparing their properties with the most well-known detoxifying systems.
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Affiliation(s)
- Maria C Martins
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157, Oeiras, Portugal
| | - Célia V Romão
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157, Oeiras, Portugal
| | - Filipe Folgosa
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157, Oeiras, Portugal
| | - Patrícia T Borges
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157, Oeiras, Portugal
| | - Carlos Frazão
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157, Oeiras, Portugal
| | - Miguel Teixeira
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157, Oeiras, Portugal.
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23
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Biswas S, Lau N, Borovik AS, Hendrich MP, Bominaar EL. Analysis of the Puzzling Exchange-Coupling Constants in a Series of Heterobimetallic Complexes. Inorg Chem 2019; 58:9150-9160. [DOI: 10.1021/acs.inorgchem.9b00757] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Saborni Biswas
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Nathanael Lau
- Department of Chemistry, University of California−Irvine, 1102 Natural Sciences II, Irvine, California 92697, United States
| | - A. S. Borovik
- Department of Chemistry, University of California−Irvine, 1102 Natural Sciences II, Irvine, California 92697, United States
| | - Michael P. Hendrich
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Emile L. Bominaar
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
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24
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Weitz AC, Giri N, Frederick RE, Kurtz DM, Bominaar EL, Hendrich MP. Spectroscopy and DFT Calculations of Flavo-Diiron Nitric Oxide Reductase Identify Bridging Structures of NO-Coordinated Diiron Intermediates. ACS Catal 2018; 8:11704-11715. [PMID: 31263628 PMCID: PMC6602092 DOI: 10.1021/acscatal.8b03051] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Flavo-diiron proteins (FDPs) are widespread in anaerobic bacteria, archaea, and protozoa, where they serve as the terminal components of dioxygen and nitric oxide reductive scavenging pathways. FDPs contain an N,O-ligated diiron site adjacent to a flavin mononucleotide (FMN) cofactor. The diiron site is structurally similar to those in hemerythrin, ribonucleotide reductase, and methane monooxygenase. However, only FDPs turn over NO to N2O at significant rates and yields. Previous studies revealed sequential binding of two NO molecules to the diferrous site, forming mono- and dinitrosyl intermediates leading to N2O formation. In the present work, these mono- and dinitrosyl intermediates have been characterized by EPR and Mössbauer spectroscopies and DFT calculations. Our results show that the iron proximal to the cofactor binds the first NO to form the diiron mononitrosyl complex, implying the iron distal to the FMN binds the second NO to form the diiron dinitrosyl intermediate. The exchange-coupling constants, J (H = JS1·S2), were found to differ substantially, +17 cm-1 for the diiron mononitrosyl and +60 cm-1 for the diiron dinitrosyl. Notwithstanding this large difference, our findings indicate retention of at least one hydroxo bridge throughout the NOR catalytic cycle. The Mossbauer hyperfine parameters and DFT calculations confirmed a semibridging NO- ligand in the mononitrosyl intermediate that lowers the exchange parameter. The DFT calculations on the dinitrosyl intermediate suggest a contribution to J from direct exchange between the S = 1 spins on the NO- ligands, which could initiate N-N bond formation. Our results provide insight into why FDPs are the only known nonheme diiron enzymes that competently turn over NO to N2O.
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Affiliation(s)
- Andrew C. Weitz
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Nitai Giri
- Department of Chemistry, University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Rosanne E. Frederick
- Department of Chemistry, University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Donald M. Kurtz
- Department of Chemistry, University of Texas at San Antonio, San Antonio, Texas 78249, United States
| | - Emile L. Bominaar
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Michael P. Hendrich
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
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25
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Dong HT, White CJ, Zhang B, Krebs C, Lehnert N. Non-Heme Diiron Model Complexes Can Mediate Direct NO Reduction: Mechanistic Insight into Flavodiiron NO Reductases. J Am Chem Soc 2018; 140:13429-13440. [DOI: 10.1021/jacs.8b08567] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hai T. Dong
- Department of Chemistry, The University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Corey J. White
- Department of Chemistry, The University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Bo Zhang
- Department of Chemistry and Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Carsten Krebs
- Department of Chemistry and Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Nicolai Lehnert
- Department of Chemistry, The University of Michigan, Ann Arbor, Michigan 48109-1055, United States
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26
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Safaei E, Alaji Z, Panahi F, Wojtczak A, Jagličić JZ. Synthesis and characterization of a novel oxo-bridged binuclear iron( iii) complex: its catalytic application in the synthesis of benzoxazoles using benzyl alcohol in water. NEW J CHEM 2018. [DOI: 10.1039/c8nj00921j] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
A novel oxo-bridged binuclear iron(iii) complex was found to be an efficient catalyst in the synthesis of benzoxazoles from benzyl alcohols.
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Affiliation(s)
- Elham Safaei
- Department of Chemistry
- College of Sciences
- Shiraz University
- Shiraz
- Iran
| | - Zahra Alaji
- Institute for Advanced Studies in Basic Sciences (IASBS)
- Zanjan
- Iran
| | - Farhad Panahi
- Department of Chemistry
- College of Sciences
- Shiraz University
- Shiraz
- Iran
| | | | - Janez Zvonko Jagličić
- Institute of Mathematics
- Physics and Mechanics & Faculty of Civil and Geodetic Engineering
- University of Ljubljana
- Ljubljana
- Slovenia
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