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Sharma VK, Saini A, Fridman N, Gray HB, Gross Z. Reversible Reactions of Nitric Oxide with a Binuclear Iron(III) Nitrophorin Mimic. Chemistry 2024; 30:e202302860. [PMID: 37953366 DOI: 10.1002/chem.202302860] [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: 09/01/2023] [Revised: 11/03/2023] [Accepted: 11/06/2023] [Indexed: 11/14/2023]
Abstract
Construction of functional synthetic systems that can reversibly bind and transport the most biologically important gaseous molecules, oxygen and nitric oxide (NO), remains a contemporary challenge. Myoglobin and nitrophorin perform these respective tasks employing a protein-embedded heme center where one axial iron site is occupied by a histidine residue and the other is available for small molecule ligation, structural features that are extremely difficult to mimic in protein-free environments. Indeed, the hitherto reported designs rely on sophisticated multistep syntheses for limiting access to one of the two axial coordination sites in small molecules. We have shown previously that binuclear Ga(III) and Al(III) corroles have available axial sites, and now report a redox-active binuclear Fe(III) corrole, (1-Fe)2 , in which each (corrolato)Fe(III) center is 5-coordinate, with one axial site occupied by an imidazole from the other corrole. The binuclear structure is further stabilized by attractive forces between the corrole π systems. Reaction of NO with (1-Fe)2 affords mononuclear iron nitrosyls, and of functional relevance, the reaction is reversible: nitric oxide is released upon purging the nitrosyls with inert gases, thereby restoring (1-Fe)2 in solutions or films.
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Affiliation(s)
- Vinay K Sharma
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology Institution, Haifa, 32000, Israel
| | - Azad Saini
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology Institution, Haifa, 32000, Israel
| | - Natalia Fridman
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology Institution, Haifa, 32000, Israel
| | - Harry B Gray
- Beckman Institute, California Institute of Technology, Pasadena, California, 91125, USA
| | - Zeev Gross
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology Institution, Haifa, 32000, Israel
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2
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Phung QM, Nam HN, Ghosh A. Local Oxidation States in {FeNO} 6-8 Porphyrins: Insights from DMRG/CASSCF-CASPT2 Calculations. Inorg Chem 2023. [PMID: 38010736 DOI: 10.1021/acs.inorgchem.3c03689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
A first DMRG/CASSCF-CASPT2 study of a series of paradigmatic {FeNO}6, {FeNO}7, and {FeNO}8 heme-nitrosyl complexes has led to substantial new insight as well as uncovered key shortcomings of the DFT approach. By virtue of its balanced treatment of static and dynamic correlation, the calculations have provided some of the most authoritative information available to date on the energetics of low- versus high-spin states of different classes of heme-nitrosyl complexes. Thus, the calculations indicate low doublet-quartet gaps of 1-4 kcal/mol for {FeNO}7 complexes and high singlet-triplet gaps of ≳20 kcal/mol for both {FeNO}6 and {FeNO}8 complexes. In contrast, DFT calculations yield widely divergent spin state gaps as a function of the exchange-correlation functional. DMRG-CASSCF calculations also help calibrate DFT spin densities for {FeNO}7 complexes, pointing to those obtained from classic pure functionals as the most accurate. The general picture appears to be that nearly all the spin density of Fe[P](NO) is localized on the Fe, while the axial ligand imidazole (ImH) in Fe[P](NO)(ImH) pushes a part of the spin density onto the NO moiety. An analysis of the DMRG-CASSCF wave function in terms of localized orbitals and of the resulting configuration state functions in terms of resonance forms with varying NO(π*) occupancies has allowed us to address the longstanding question of local oxidation states in heme-nitrosyl complexes. The analysis indicates NO(neutral) resonance forms [i.e., Fe(II)-NO0 and Fe(III)-NO0] as the major contributors to both {FeNO}6 and {FeNO}7 complexes. This finding is at variance with the common formulation of {FeNO}6 hemes as Fe(II)-NO+ species but is consonant with an Fe L-edge XAS analysis by Solomon and co-workers. For the {FeNO}8 complex {Fe[P](NO)}-, our analysis suggests a resonance hybrid description: Fe(I)-NO0 ↔ Fe(II)-NO-, in agreement with earlier DFT studies. Vibrational analyses of the compounds studied indicate an imperfect but fair correlation between the NO stretching frequency and NO(π*) occupancy, highlighting the usefulness of vibrational data as a preliminary indicator of the NO oxidation state.
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Affiliation(s)
- Quan Manh Phung
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601, Japan
| | - Ho Ngoc Nam
- Institute of Materials Innovation, Institutes of Innovation for Future Society, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601, Japan
- Department of Chemical Systems Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
| | - Abhik Ghosh
- Department of Chemistry, UiT the Arctic University of Norway, N-9037 Tromsø, Norway
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3
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Manickas EC, LaLonde AB, Hu MY, Alp EE, Lehnert N. Stabilization of a Heme-HNO Model Complex Using a Bulky Bis-Picket Fence Porphyrin and Reactivity Studies with NO. J Am Chem Soc 2023; 145:23014-23026. [PMID: 37824502 DOI: 10.1021/jacs.3c05333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2023]
Abstract
Nitroxyl, HNO/NO-, the one-electron reduced form of NO, is suggested to take part in distinct signaling pathways in mammals and is also a key intermediate in various heme-catalyzed NOx interconversions in the nitrogen cycle. Cytochrome P450nor (Cyt P450nor) is a heme-containing enzyme that performs NO reduction to N2O in fungal denitrification. The reactive intermediate in this enzyme, termed "Intermediate I", is proposed to be an Fe-NHO/Fe-NHOH type species, but it is difficult to study its electronic structure and exact protonation state due to its instability. Here, we utilize a bulky bis-picket fence porphyrin to obtain the first stable heme-HNO model complex, [Fe(3,5-Me-BAFP)(MI)(NHO)], as a model for Intermediate I, and more generally HNO adducts of heme proteins. Due to the steric hindrance of the bis-picket fence porphyrin, [Fe(3,5-Me-BAFP)(MI)(NHO)] is stable (τ1/2 = 56 min at -30 °C), can be isolated as a solid, and is available for thorough spectroscopic characterization. In particular, we were able to solve a conundrum in the literature and provide the first full vibrational characterization of a heme-HNO complex using IR and nuclear resonance vibrational spectroscopy (NRVS). Reactivity studies of [Fe(3,5-Me-BAFP)(MI)(NHO)] with NO gas show a 91 ± 10% yield for N2O formation, demonstrating that heme-HNO complexes are catalytically competent intermediates for NO reduction to N2O in Cyt P450nor. The implications of these results for the mechanism of Cyt P450nor are further discussed.
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Affiliation(s)
- Elizabeth C Manickas
- Department of Chemistry and Department of Biophysics, The University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Ashley B LaLonde
- Department of Chemistry and Department of Biophysics, The University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Michael Y Hu
- Advanced Photon Source (APS), Argonne National Laboratory (ANL), Argonne, Illinois 60439, United States
| | - E Ercan Alp
- Advanced Photon Source (APS), Argonne National Laboratory (ANL), Argonne, Illinois 60439, United States
| | - Nicolai Lehnert
- Department of Chemistry and Department of Biophysics, The University of Michigan, Ann Arbor, Michigan 48109-1055, United States
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4
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Sarkar A, Bhakta S, Chattopadhyay S, Dey A. Role of distal arginine residue in the mechanism of heme nitrite reductases. Chem Sci 2023; 14:7875-7886. [PMID: 37502318 PMCID: PMC10370594 DOI: 10.1039/d3sc01777j] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 06/14/2023] [Indexed: 07/29/2023] Open
Abstract
Heme nitrite reductases reduce NO2- by 1e-/2H+ to NO or by 6e-/8H+ to NH4+ which are key steps in the global nitrogen cycle. Second-sphere residues, such as arginine (with a guanidine head group), are proposed to play a key role in the reaction by assisting substrate binding and hydrogen bonding and by providing protons to the active site for the reaction. The reactivity of an iron porphyrin with a NO2- covalently attached to a guanidinium arm in its 2nd sphere was investigated to understand the role of arginine residues in the 2nd sphere of heme nitrite reductases. The presence of the guanidinium residue allows the synthetic ferrous porphyrin to reduce NO2- and produce a ferrous nitrosyl species ({FeNO}7), where the required protons are provided by the guanidinium group in the 2nd sphere. However, in the presence of additional proton sources in solution, the reaction of ferrous porphyrin with NO2- results in the formation of ferric porphyrin and the release of NO. Spectroscopic and kinetic data indicated that re-protonation of the guanidine group in the 2nd sphere by an external proton source causes NO to dissociate from a ferric nitrosyl species ({FeNO}6) at rates similar to those observed for enzymatic sites. This re-protonation of the guanidine group mimics the proton recharge mechanism in the active site of NiR. DFT calculations indicated that the lability of the Fe-NO bond in the {FeNO}6 species is derived from the greater binding affinity of anions (e.g. NO2-) to the ferric center relative to neutral NO due to hydrogen bonding and electrostatic interaction of these bound anions with the protonated guanidium group in the 2nd sphere. The reduced {FeNO}7 species, once formed, is not affected significantly by the re-protonation of the guanidine residue. These results provide direct insight into the role of the 2nd sphere arginine residue present in the active sites of heme-based NiRs in determining the fate of NO2- reduction. Specifically, the findings using the synthetic model suggest that rapid re-protonation of these arginine residues may trigger the dissociation of NO from the {FeNO}6, which may also be the case in the protein active site.
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Affiliation(s)
- Ankita Sarkar
- School of Chemical Sciences, Indian Association for the Cultivation of Science 2A & 2B Raja S.C. Mullick Road Kolkata WB 700032 India
| | - Snehadri Bhakta
- School of Chemical Sciences, Indian Association for the Cultivation of Science 2A & 2B Raja S.C. Mullick Road Kolkata WB 700032 India
| | - Samir Chattopadhyay
- School of Chemical Sciences, Indian Association for the Cultivation of Science 2A & 2B Raja S.C. Mullick Road Kolkata WB 700032 India
| | - Abhishek Dey
- School of Chemical Sciences, Indian Association for the Cultivation of Science 2A & 2B Raja S.C. Mullick Road Kolkata WB 700032 India
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5
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Ren W, Schulz CE, Shroyer MH, Xu W, Xi S, An P, Guo W, Li J. Electronic Configurations and the Effect of Peripheral Substituents of (Nitrosyl)iron Corroles. Inorg Chem 2022; 61:20385-20396. [DOI: 10.1021/acs.inorgchem.2c03026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Wanjie Ren
- College of Materials Science and Optoelectronic Technology and Chinese Academy of Sciences Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Yanqi Lake, Huairou District, Beijing101408, P. R. China
| | - Charles E. Schulz
- Department of Physics and Astronomy, Knox College, Galesburg, Illinois61401, United States
| | - Mark H. Shroyer
- Department of Physics and Astronomy, Knox College, Galesburg, Illinois61401, United States
| | - Wei Xu
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences (CAS), Beijing100049, P. R. China
- RICMASS, Rome International Center for Materials Science Superstripes, Via dei Sabelli 119A, Rome00185, Italy
| | - Shibo Xi
- Institute of Chemical and Engineering Sciences, Agency for Science, Technology and Research, 1 Pesek Road, Jurong Island, Singapore627833, Singapore
| | - Pengfei An
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences (CAS), Beijing100049, P. R. China
| | - Wenping Guo
- National Energy Center for Coal to Clean Fuels, Synfuels China Co., Ltd., Huairou District, Beijing101400, P. R. China
| | - Jianfeng Li
- College of Materials Science and Optoelectronic Technology and Chinese Academy of Sciences Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Yanqi Lake, Huairou District, Beijing101408, P. R. China
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6
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Zheng Y, Deng W, Liu D, Li Y, Peng K, Lorimer GH, Wang J. Redox and spectroscopic properties of mammalian nitrite reductase-like hemoproteins. J Inorg Biochem 2022; 237:111982. [PMID: 36116154 DOI: 10.1016/j.jinorgbio.2022.111982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 08/24/2022] [Accepted: 08/25/2022] [Indexed: 01/18/2023]
Abstract
Besides the canonical pathway of L-arginine oxidation to produce nitric oxide (NO) in vivo, the nitrate-nitrite-NO pathway has been widely accepted as another source for circulating NO in mammals, especially under hypoxia. To date, there have been at least ten heme-containing nitrite reductase-like proteins discovered in mammals with activities mainly identified in vitro, including four globins (hemoglobin, myoglobin, neuroglobin (Ngb), cytoglobin (Cygb)), three mitochondrial respiratory chain enzymes (cytochrome c oxidase, cytochrome bc1, cytochrome c), and three other heme proteins (endothelial nitric oxide synthase, cytochrome P450 and indoleamine 2,3-dioxygenase 1 (IDO1)). The pathophysiological functions of these proteins are closely related to their redox and spectroscopic properties, as well as their protein structure, although the physiological roles of Ngb, Cygb and IDO1 remain unclear. So far, comprehensive summaries of the redox and spectroscopic properties of these nitrite reductase-like hemoproteins are still lacking. In this review, we have mainly summarized the published data on the application of ultraviolet-visible, electron paramagnetic resonance, circular dichroism and resonance Raman spectroscopies, and X-ray crystallography in studying nitrite reductase-like activity of these 10 proteins, in order to sort out the relationships among enzymatic function, structure and spectroscopic characterization, which might help in understanding their roles in redox biology and medicine.
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Affiliation(s)
- Yunlong Zheng
- Hubei University of Technology Autism & Depression Diagnosis and Intervention Institute, Hubei University of Technology, Wuhan, Hubei, China; International Joint Research Center for General Health, Precision Medicine & Nutrition, Hubei University of Technology, Wuhan, Hubei, China; Department of Biomedicine and Biopharmacology, Hubei University of Technology, Wuhan, Hubei, China
| | - Wenwen Deng
- Hubei University of Technology Autism & Depression Diagnosis and Intervention Institute, Hubei University of Technology, Wuhan, Hubei, China; International Joint Research Center for General Health, Precision Medicine & Nutrition, Hubei University of Technology, Wuhan, Hubei, China; Department of Biomedicine and Biopharmacology, Hubei University of Technology, Wuhan, Hubei, China
| | - Di Liu
- Hubei University of Technology Autism & Depression Diagnosis and Intervention Institute, Hubei University of Technology, Wuhan, Hubei, China; International Joint Research Center for General Health, Precision Medicine & Nutrition, Hubei University of Technology, Wuhan, Hubei, China; Department of Biomedicine and Biopharmacology, Hubei University of Technology, Wuhan, Hubei, China
| | - Youheng Li
- Hubei University of Technology Autism & Depression Diagnosis and Intervention Institute, Hubei University of Technology, Wuhan, Hubei, China; International Joint Research Center for General Health, Precision Medicine & Nutrition, Hubei University of Technology, Wuhan, Hubei, China; Department of Biomedicine and Biopharmacology, Hubei University of Technology, Wuhan, Hubei, China
| | - Kang Peng
- Hubei University of Technology Autism & Depression Diagnosis and Intervention Institute, Hubei University of Technology, Wuhan, Hubei, China; International Joint Research Center for General Health, Precision Medicine & Nutrition, Hubei University of Technology, Wuhan, Hubei, China; Department of Biomedicine and Biopharmacology, Hubei University of Technology, Wuhan, Hubei, China
| | | | - Jun Wang
- Hubei University of Technology Autism & Depression Diagnosis and Intervention Institute, Hubei University of Technology, Wuhan, Hubei, China; International Joint Research Center for General Health, Precision Medicine & Nutrition, Hubei University of Technology, Wuhan, Hubei, China; Department of Biomedicine and Biopharmacology, Hubei University of Technology, Wuhan, Hubei, China.
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7
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Kim Y, Sridharan A, Suess DLM. The Elusive Mononitrosylated [Fe 4 S 4 ] Cluster in Three Redox States. Angew Chem Int Ed Engl 2022; 61:e202213032. [PMID: 36194444 PMCID: PMC9669169 DOI: 10.1002/anie.202213032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Indexed: 11/06/2022]
Abstract
Iron-sulfur clusters are well-established targets in biological nitric oxide (NO) chemistry, but the key intermediate in these processes-a mononitrosylated [Fe4 S4 ] cluster-has not been fully characterized in a protein or a synthetic model thereof. Here, we report the synthesis of a three-member redox series of isostructural mononitrosylated [Fe4 S4 ] clusters. Mononitrosylation was achieved by binding NO to a 3 : 1 site-differentiated [Fe4 S4 ]+ cluster; subsequent oxidation and reduction afforded the other members of the series. All three clusters feature a local high-spin Fe3+ center antiferromagnetically coupled to 3 [NO]- . The observation of an anionic NO ligand suggests that NO binding is accompanied by formal electron transfer from the cluster to NO. Preliminary reactivity studies with the monocationic cluster demonstrate that exposure to excess NO degrades the cluster, supporting the intermediacy of mononitrosylated intermediates in NO sensing/signaling.
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Affiliation(s)
- Youngsuk Kim
- Department of ChemistryMassachusetts Institute of Technology77 Massachusetts AveCambridgeMA 02139USA
- Department of ChemistryPusan National UniversityBusan46241Republic of Korea
| | - Arun Sridharan
- Department of ChemistryMassachusetts Institute of Technology77 Massachusetts AveCambridgeMA 02139USA
| | - Daniel L. M. Suess
- Department of ChemistryMassachusetts Institute of Technology77 Massachusetts AveCambridgeMA 02139USA
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8
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Kumbhakar S, Gupta P, Giri B, Muley A, Karumban KS, Misra A, Maji S. Photolability of NO in ruthenium nitrosyls with pentadentate ligand induces exceptional cytotoxicity towards VCaP, 22Rv1 and A549 cancer cells under therapeutic condition. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.133419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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9
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Fateminasab F, de la Lande A, Omidyan R. Insights into the effect of distal histidine and water hydrogen bonding on NO ligation to ferrous and ferric heme: a DFT study. RSC Adv 2022; 12:4703-4713. [PMID: 35425484 PMCID: PMC8981399 DOI: 10.1039/d1ra08398h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 01/30/2022] [Indexed: 11/29/2022] Open
Abstract
The effect of distal histidine on ligation of NO to ferrous and ferric-heme, has been investigated with the high-level density functional theoretical (DFT) method. It has been predicted that the distal histidine significantly stabilizes the interaction of NO ferrous-heme (by −2.70 kcal mol−1). Also, water hydrogen bonding is quite effective in strengthening the Fe–NO bond in ferrous heme. In contrast in ferric heme, due to the large distance between the H2O and O(NO) and lack of hydrogen bonding, the distal histidine exhibits only a slight effect on the binding of NO to the ferric analogue. Concerning the bond nature of FeII–NO and FeIII–NO in heme, a QTAIM analysis predicts a partially covalent and ionic bond nature in both systems. The effect of distal histidine on ligation of NO to ferrous and ferric-heme, has been investigated with the high-level density functional theoretical (DFT) method.![]()
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Affiliation(s)
- Fatemeh Fateminasab
- Department of Chemistry, University of Isfahan 81746-73441 Isfahan Iran +98 31 3668 9732
| | - Aurelien de la Lande
- Université Paris-Saclay, CNRS, Institut de Chimie Physique, UMR8000 91405 Orsay France
| | - Reza Omidyan
- Department of Chemistry, University of Isfahan 81746-73441 Isfahan Iran +98 31 3668 9732
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10
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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: 96] [Impact Index Per Article: 32.0] [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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11
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Gallego CM, Mazzeo A, Gaviglio C, Pellegrino J, Doctorovich F. Structure and Reactivity of NO/NO
+
/NO
−
Pincer and Porphyrin Complexes. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100682] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Cecilia Mariel Gallego
- Departamento de Química Inorgánica, Analítica y Química Física Facultad de Ciencias Exactas y Naturales Universidad de Buenos Aires Pabellón 2, Ciudad Universitaria Buenos Aires Argentina
| | - Agostina Mazzeo
- Departamento de Química Inorgánica, Analítica y Química Física Facultad de Ciencias Exactas y Naturales Universidad de Buenos Aires Pabellón 2, Ciudad Universitaria Buenos Aires Argentina
| | - Carina Gaviglio
- Departamento de Física de la Materia Condensada Comisión Nacional de Energía Atómica, CAC-GIyANN Avenida General Paz 1499, San Martín Buenos Aires Argentina
| | - Juan Pellegrino
- Departamento de Química Inorgánica, Analítica y Química Física Facultad de Ciencias Exactas y Naturales Universidad de Buenos Aires Pabellón 2, Ciudad Universitaria Buenos Aires Argentina
| | - Fabio Doctorovich
- Departamento de Química Inorgánica, Analítica y Química Física Facultad de Ciencias Exactas y Naturales Universidad de Buenos Aires Pabellón 2, Ciudad Universitaria Buenos Aires Argentina
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12
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Khade R, Abucayon EG, Powell DR, Richter-Addo GB, Zhang Y. Insights into the Observed trans-Bond Length Variations upon NO Binding to Ferric and Ferrous Porphyrins with Neutral Axial Ligands. ACS OMEGA 2021; 6:24777-24787. [PMID: 34604659 PMCID: PMC8482462 DOI: 10.1021/acsomega.1c03610] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Indexed: 05/27/2023]
Abstract
NO is well-known for its trans effect. NO binding to ferrous hemes of the form (por)Fe(L) (L = neutral N-based ligand) to give the {FeNO}7 (por)Fe(NO)(L) product results in a lengthening of the axial trans Fe-L bond. In contrast, NO binding to the ferric center in [(por)Fe(L)]+ to give the {FeNO}6 [(por)Fe(NO)(L)]+ product results in a shortening of the trans Fe-L bond. NO binding to both ferrous and ferric centers involves the lowering of their spin states. Density functional theory (DFT) calculations were used to probe the experimentally observed trans-bond shortening in some NO adducts of ferric porphyrins. We show that the strong σ antibonding interaction of d z 2 and the axial (L) ligand p orbitals present in the Fe(II) systems is absent in the Fe(III) systems, as it is now in an unoccupied orbital. This feature, combined with a lowering of spin state upon NO binding, provides a rationale for the observed net trans-bond shortening in the {FeNO}6 but not the {FeNO}7 derivatives.
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Affiliation(s)
- Rahul
L. Khade
- Department
of Chemistry and Chemical Biology, Stevens Institute of Technology, Castle Point on Hudson, Hoboken, New Jersey 07030, Unites States
| | - Erwin G. Abucayon
- Price
Foundation Institute of Structural Biology and Department of Chemistry
and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
| | - Douglas R. Powell
- Price
Foundation Institute of Structural Biology and Department of Chemistry
and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
| | - George B. Richter-Addo
- Price
Foundation Institute of Structural Biology and Department of Chemistry
and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
| | - Yong Zhang
- Department
of Chemistry and Chemical Biology, Stevens Institute of Technology, Castle Point on Hudson, Hoboken, New Jersey 07030, Unites States
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13
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Sweeny EA, Hunt AP, Batka AE, Schlanger S, Lehnert N, Stuehr DJ. Nitric oxide and heme-NO stimulate superoxide production by NADPH oxidase 5. Free Radic Biol Med 2021; 172:252-263. [PMID: 34139309 PMCID: PMC8355125 DOI: 10.1016/j.freeradbiomed.2021.06.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/04/2021] [Accepted: 06/09/2021] [Indexed: 01/05/2023]
Abstract
Nitric oxide (NO) is a ubiquitous cell signaling molecule which mediates widespread and diverse processes in the cell. These NO dependent effects often involve activation (e.g. NO binding to the heme group of soluble guanylyl cyclase for cGMP production) or inactivation (e.g. S-nitrosation) of protein targets. We studied the effect of NO and heme-NO on the transmembrane signaling enzyme NADPH oxidase 5 (NOX5), a heme protein which produces superoxide in response to increases in intracellular calcium. We found that treatment with NO donors increases NOX5 activity through heme-dependent effects, and that this effect could be recapitulated by the addition of heme-NO. This work adds to our understanding of NOX5 regulation in the cell but also provides a framework for understanding how NO could cause widespread changes in hemeprotein activity based on different affinities for heme v. heme-NO, and helps explain the opposing roles NO plays in activation and inactivation of hemeprotein targets.
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Affiliation(s)
- Elizabeth A Sweeny
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, OH 44195, USA
| | - Andrew P Hunt
- Department of Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Allison E Batka
- Department of Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Simon Schlanger
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, OH 44195, USA
| | - Nicolai Lehnert
- Department of Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Dennis J Stuehr
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, OH 44195, USA.
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14
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Reed CJ, Lam QN, Mirts EN, Lu Y. Molecular understanding of heteronuclear active sites in heme-copper oxidases, nitric oxide reductases, and sulfite reductases through biomimetic modelling. Chem Soc Rev 2021; 50:2486-2539. [PMID: 33475096 PMCID: PMC7920998 DOI: 10.1039/d0cs01297a] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Heme-copper oxidases (HCO), nitric oxide reductases (NOR), and sulfite reductases (SiR) catalyze the multi-electron and multi-proton reductions of O2, NO, and SO32-, respectively. Each of these reactions is important to drive cellular energy production through respiratory metabolism and HCO, NOR, and SiR evolved to contain heteronuclear active sites containing heme/copper, heme/nonheme iron, and heme-[4Fe-4S] centers, respectively. The complexity of the structures and reactions of these native enzymes, along with their large sizes and/or membrane associations, make it challenging to fully understand the crucial structural features responsible for the catalytic properties of these active sites. In this review, we summarize progress that has been made to better understand these heteronuclear metalloenzymes at the molecular level though study of the native enzymes along with insights gained from biomimetic models comprising either small molecules or proteins. Further understanding the reaction selectivity of these enzymes is discussed through comparisons of their similar heteronuclear active sites, and we offer outlook for further investigations.
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Affiliation(s)
- Christopher J Reed
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urban, IL 61801, USA.
| | - Quan N Lam
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urban, IL 61801, USA
| | - Evan N Mirts
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA and Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Yi Lu
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urban, IL 61801, USA. and Department of Biochemistry, University of Illinois at Urbana-Champaign, Urban, IL 61801, USA and Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA and Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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15
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Dong HT, Chalkley MJ, Oyala PH, Zhao J, Alp EE, Hu MY, Peters JC, Lehnert N. Exploring the Limits of Dative Boratrane Bonding: Iron as a Strong Lewis Base in Low-Valent Non-Heme Iron-Nitrosyl Complexes. Inorg Chem 2020; 59:14967-14982. [PMID: 32989992 PMCID: PMC7640944 DOI: 10.1021/acs.inorgchem.0c01686] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
We previously reported the synthesis and preliminary characterization of a unique series of low-spin (ls) {FeNO}8-10 complexes supported by an ambiphilic trisphosphineborane ligand, [Fe(TPB)(NO)]+/0/-. Herein, we use advanced spectroscopic techniques and density functional theory (DFT) calculations to extract detailed information as to how the bonding changes across the redox series. We find that, in spite of the highly reduced nature of these complexes, they feature an NO+ ligand throughout with strong Fe-NO π-backbonding and essentially closed-shell electronic structures of their FeNO units. This is enabled by an Fe-B interaction that is present throughout the series. In particular, the most reduced [Fe(TPB)(NO)]- complex, an example of a ls-{FeNO}10 species, features a true reverse dative Fe → B bond where the Fe center acts as a strong Lewis-base. Hence, this complex is in fact electronically similar to the ls-{FeNO}8 system, with two additional electrons "stored" on site in an Fe-B single bond. The outlier in this series is the ls-{FeNO}9 complex, due to spin polarization (quantified by pulse EPR spectroscopy), which weakens the Fe-NO bond. These data are further contextualized by comparison with a related N2 complex, [Fe(TPB)(N2)]-, which is a key intermediate in Fe(TPB)-catalyzed N2 fixation. Our present study finds that the Fe → B interaction is key for storing the electrons needed to achieve a highly reduced state in these systems, and highlights the pitfalls associated with using geometric parameters to try to evaluate reverse dative interactions, a finding with broader implications to the study of transition metal complexes with boratrane and related ligands.
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Affiliation(s)
- Hai T. Dong
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
| | - Matthew J. Chalkley
- Department of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Paul H. Oyala
- Department of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Jiyong Zhao
- Advanced Photon Source (APS), Argonne National Laboratory (ANL), Argonne, Illinois 60439, United States
| | - E. Ercan Alp
- Advanced Photon Source (APS), Argonne National Laboratory (ANL), Argonne, Illinois 60439, United States
| | - Michael Y. Hu
- Advanced Photon Source (APS), Argonne National Laboratory (ANL), Argonne, Illinois 60439, United States
| | - Jonas C. Peters
- Department of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Nicolai Lehnert
- Department of Chemistry and Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, United States
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16
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Giri B, Saini T, Kumbhakar S, Selvan K K, Muley A, Misra A, Maji S. Near-IR light-induced photorelease of nitric oxide (NO) on ruthenium nitrosyl complexes: formation, reactivity, and biological effects. Dalton Trans 2020; 49:10772-10785. [PMID: 32706352 DOI: 10.1039/d0dt01788d] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Polypyridyl backbone nitrosyl complexes of ruthenium with the molecular framework [RuII(antpy)(bpy)NO+/˙]n+ [4](PF6)3 (n = 3), [4](PF6)2 (n = 2), where antpy = 4'-(anthracene-9-yl)-2,2':6',2''-terpyridine and bpy = 2,2'-bipyridine, were synthesized via a stepwise synthetic route from the chloro precursor [RuII(antpy)(bpy)(Cl)](PF6) [1](PF6) and [RuII(antpy)(bpy)(CH3CN)](PF6)2 [2](PF6)2 and [RuII(antpy)(bpy)(NO2)](PF6) [3](PF6). After column chromatographic purification, all the synthesized complexes were fully characterized using different spectroscopic and analytical techniques including mass spectroscopy, 1H NMR, FT-IR and UV-vis spectrophotometry. The Ru-NO stretching frequency of [4](PF6)3 was observed at 1941 cm-1, which suggests moderately strong Ru-NO bonding. A massive shift in the νNO frequency occurred at Δν = 329 cm-1 (solid) upon reducing [4](PF6)3 to [4](PF6)2. To understand the molecular integrity of the complexes, the structure of [3](PF6) was successfully determined by X-ray crystallography. The redox properties of [4](PF6)3 were thoroughly investigated together with the other precursor complexes. The rate constants for the first-order photo-release of NO from [4](PF6)3 and [4](PF6)2 were determined to be 8.01 × 10-3 min-1 (t1/2 ∼ 86 min) and 3.27 × 10-2 min-1 (t1/2 ∼ 21 min), respectively, when exposed to a 200 W Xenon light. Additionally, the photo-cleavage of Ru-NO occurred within ∼2 h when [4](PF6)3 was irradiated with an IR light source (>700 nm) at room temperature. The first-order rate constant of 9.4 × 10-3 min-1 (t1/2 ∼ 73 min) shows the efficacy of the system and its capability to release NO in the photo-therapeutic window. The released NO triggered by light was trapped by reduced myoglobin, a biologically relevant target protein. The one-electron reduction of [4](PF6)3 to [4](PF6)2 was systematically carried out chemically (hydrazine hydrate), electrochemically and biologically. In the biological reduction, it was found that the reduction is much slower with double-stranded DNA compared to a single-stranded oligonucleotide (CAAGGCCAACCGCGAGAAGATGAC). Moreover, [4](PF6)3 exhibited significant photo-toxicity to the VCaP prostate cancer cell line upon irradiation with a visible light source (IC50 ∼ 8.97 μM).
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Affiliation(s)
- Bishnubasu Giri
- Department of Chemistry, Indian Institute of Technology, Hyderabad, Kandi, Sangareddy 502285, Telangana, India.
| | - Taruna Saini
- Department of Biotechnology, Indian Institute of Technology, Hyderabad, Kandi, Sangareddy 502285, Telangana, India
| | - Sadananda Kumbhakar
- Department of Chemistry, Indian Institute of Technology, Hyderabad, Kandi, Sangareddy 502285, Telangana, India.
| | - Kalai Selvan K
- Department of Chemistry, Indian Institute of Technology, Hyderabad, Kandi, Sangareddy 502285, Telangana, India.
| | - Arabinda Muley
- Department of Chemistry, Indian Institute of Technology, Hyderabad, Kandi, Sangareddy 502285, Telangana, India.
| | - Ashish Misra
- Department of Biotechnology, Indian Institute of Technology, Hyderabad, Kandi, Sangareddy 502285, Telangana, India
| | - Somnath Maji
- Department of Chemistry, Indian Institute of Technology, Hyderabad, Kandi, Sangareddy 502285, Telangana, India.
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17
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Das S, Kulbir, Ghosh S, Chandra Sahoo S, Kumar P. Nitric oxide monooxygenation (NOM) reaction of cobalt-nitrosyl {Co(NO)} 8 to Co II-nitrito {Co II(NO 2 -)}: base induced hydrogen gas (H 2) evolution. Chem Sci 2020; 11:5037-5042. [PMID: 34122960 PMCID: PMC8159239 DOI: 10.1039/d0sc01572e] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 04/24/2020] [Indexed: 12/21/2022] Open
Abstract
Here, we report the nitric oxide monooxygenation (NOM) reactions of a CoIII-nitrosyl complex (1, {Co-NO}8) in the presence of mono-oxygen reactive species, i.e., a base (OH-, tetrabutylammonium hydroxide (TBAOH) or NaOH/15-crown-5), an oxide (O2- or Na2O/15-crown-5) and water (H2O). The reaction of 1 with OH- produces a CoII-nitrito complex {3, (CoII-NO2 -)} and hydrogen gas (H2), via the formation of a putative N-bound Co-nitrous acid intermediate (2, {Co-NOOH}+). The homolytic cleavage of the O-H bond of proposed [Co-NOOH]+ releases H2 via a presumed CoIII-H intermediate. In another reaction, 1 generates CoII-NO2 - when reacted with O2- via an expected CoI-nitro (4) intermediate. However, complex 1 is found to be unreactive towards H2O. Mechanistic investigations using 15N-labeled-15NO and 2H-labeled-NaO2H (NaOD) evidently revealed that the N-atom in CoII-NO2 - and the H-atom in H2 gas are derived from the nitrosyl ligand and OH- moiety, respectively.
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Affiliation(s)
- Sandip Das
- Department of Chemistry, Indian Institute of Science Education and Research (IISER) Tirupati 517507 India
| | - Kulbir
- Department of Chemistry, Indian Institute of Science Education and Research (IISER) Tirupati 517507 India
| | - Somnath Ghosh
- Department of Chemistry, Indian Institute of Science Education and Research (IISER) Tirupati 517507 India
| | | | - Pankaj Kumar
- Department of Chemistry, Indian Institute of Science Education and Research (IISER) Tirupati 517507 India
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18
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Ferric nitrosylated myoglobin catalyzes peroxynitrite scavenging. J Biol Inorg Chem 2020; 25:361-370. [PMID: 32172452 DOI: 10.1007/s00775-020-01767-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 02/13/2020] [Indexed: 01/12/2023]
Abstract
Myoglobin (Mb), generally taken as the molecular model of monomeric globular heme-proteins, is devoted: (i) to act as an intracellular oxygen reservoir, (ii) to transport oxygen from the sarcolemma to the mitochondria of vertebrate heart and red muscle cells, and (iii) to act as a scavenger of nitrogen and oxygen reactive species protecting mitochondrial respiration. Here, the first evidence of ·NO inhibition of ferric Mb- (Mb(III)) mediated detoxification of peroxynitrite is reported, at pH 7.2 and 20.0 °C. ·NO binds to Mb(III) with a simple equilibrium; the value of the second-order rate constant for Mb(III) nitrosylation (i.e., ·NOkon) is (6.8 ± 0.7) × 104 M-1 s-1 and the value of the first-order rate constant for Mb(III)-NO denitrosylation (i.e., ·NOkoff) is 3.1 ± 0.3 s-1. The calculated value of the dissociation equilibrium constant for Mb(III)-NO complex formation (i.e., ·NOkoff/·NOkon = (4.6 ± 0.7) × 10-5 M) is virtually the same as that directly measured (i.e., ·NOK = (3.8 ± 0.5) × 10-5 M). In the absence of ·NO, Mb(III) catalyzes the conversion of peroxynitrite to NO3-, the value of the second-order rate constant (i.e., Pkon) being (1.9 ± 0.2) × 104 M-1 s-1. However, in the presence of ·NO, Mb(III)-mediated detoxification of peroxynitrite is only partially inhibited, underlying the possibility that also Mb(III)-NO is able to catalyze the peroxynitrite isomerization, though with a reduced rate (Pkon* = (2.8 ± 0.3) × 103 M-1 s-1). These data expand the multiple roles of ·NO in modulating heme-protein actions, envisaging a delicate balancing between peroxynitrite and ·NO, which is modulated through the relative amount of Mb(III) and Mb(III)-NO.
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19
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Giri B, Kumbhakar S, Selvan K K, Muley A, Maji S. Ruthenium nitrosyl complexes with the molecular framework [Ru II(dmdptz)(bpy)(NO)] n+ (dmdptz: N, N-dimethyl-4,6-di(pyridin-2-yl)-1,3,5-triazin-2-amine and bpy: 2,2′-bipyridine). Electronic structure, reactivity aspects, photorelease, and scavenging of NO. NEW J CHEM 2020. [DOI: 10.1039/d0nj03923c] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Two ruthenium nitrosyl complexes have been stabilized both in {Ru–NO}6 and {Ru–NO}7 configurations which show facile photocleavage of Ru–NO bond on exposure to visible light. The photo liberated NO is captured by reduced myoglobin.
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Affiliation(s)
- Bishnubasu Giri
- Department of Chemistry
- Indian Institute of Technology
- Sangareddy 502285
- India
| | | | - Kalai Selvan K
- Department of Chemistry
- Indian Institute of Technology
- Sangareddy 502285
- India
| | - Arabinda Muley
- Department of Chemistry
- Indian Institute of Technology
- Sangareddy 502285
- India
| | - Somnath Maji
- Department of Chemistry
- Indian Institute of Technology
- Sangareddy 502285
- India
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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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Sadraei R, Murphy RS, Laurenti E, Magnacca G. Characterization Methodology To Evaluate the Activity of Supported Soybean Peroxidase. Ind Eng Chem Res 2019. [DOI: 10.1021/acs.iecr.9b03495] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - R. Scott Murphy
- Department of Chemistry and Biochemistry, University of Regina, 3737 Wascana Parkway, Regina, Saskatchewan S4S 0A2, Canada
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22
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Nath AK, Ghosh C, Roy M, Seal M, Ghosh Dey S. Nitrite reductase activity of heme and copper bound Aβ peptides. Dalton Trans 2019; 48:7451-7461. [PMID: 31086893 DOI: 10.1039/c9dt00914k] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A significant abundance of copper (Cu) and iron in amyloid β (Aβ) plaques, and several heme related metabolic disorders are directly correlated with Alzheimer's disease (AD), and these together with co-localization of Aβ plaques with heme rich deposits in the brains of AD sufferers indicates a possible association of the said metals with the disease. Recently, the Aβ peptides have been found to bind heme and Cu individually as well as simultaneously. Another significant finding relevant to this is the lower levels of nitrite and nitrate found in the brains of patients suffering from AD. In this study, a combination of absorption and electron paramagnetic resonance spectroscopy and kinetic assays have been used to study the interaction of nitrite with the metal bound Aβ complexes. The data indicate that heme(III)-Cu(i)-Aβ, heme(II)-Cu(i)-Aβ, heme(II)-Aβ and Cu(i)-Aβ can reduce nitrite to nitric oxide (NO), an important biological messenger also related to AD, and thus behave as nitrite reductases. However these complexes reduce nitrite at different rates with heme(III)-Cu(i)-Aβ being the fastest following an inner sphere electron transfer mechanism. The rest of the metal-Aβ adducts follow an outer sphere electron transfer mechanism during nitrite reduction. Protonation from the Arg5 residue triggering the N-O bond heterolysis in heme(III) bound nitrite with a simultaneous electron transfer from the Cu(i) center to produce NO is the rate determining step, indicating a proton transfer followed by electron transfer (PTET) mechanism.
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Affiliation(s)
- Arnab Kumar Nath
- School of Chemical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India.
| | - Chandradeep Ghosh
- School of Chemical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India.
| | - Madhuparna Roy
- School of Chemical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India.
| | - Manas Seal
- School of Chemical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India.
| | - Somdatta Ghosh Dey
- School of Chemical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India.
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23
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Hunt AP, Lehnert N. The Thiolate Trans Effect in Heme {FeNO}6 Complexes and Beyond: Insight into the Nature of the Push Effect. Inorg Chem 2019; 58:11317-11332. [DOI: 10.1021/acs.inorgchem.9b00091] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Andrew P. Hunt
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
| | - Nicolai Lehnert
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
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24
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Electrochemical characterization of Fe center from hemin binding with Yersinia pestis heme-protein acquisition system. Electrochim Acta 2019. [DOI: 10.1016/j.electacta.2018.12.109] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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25
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Aarabi M, Omidyan R, Soorkia S, Grégoire G, Broquier M, Crestoni ME, de la Lande A, Soep B, Shafizadeh N. The dramatic effect of N-methylimidazole on trans axial ligand binding to ferric heme: experiment and theory. Phys Chem Chem Phys 2019; 21:1750-1760. [PMID: 30623949 DOI: 10.1039/c8cp06210b] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The binding energy of CO, O2 and NO to isolated ferric heme, [FeIIIP]+, was studied in the presence and absence of a σ donor (N-methylimidazole and histidine) as the trans axial ligand. This study combines the experimental determination of binding enthalpies by equilibrium measurements in a low temperature ion trap using the van't Hoff equation and high level DFT calculations. It was found that the presence of N-methylimidazole as the axial ligand on the [FeIIIP]+ porphyrin dramatically weakens the [FeIIIP-ligand]+ bond with an up to sevenfold decrease in binding energy owing to the σ donation by N-methylimidazole to the FeIII(3d) orbitals. This trans σ donor effect is characteristic of ligation to iron in hemes in both ferrous and ferric redox forms; however, to date, this has not been observed for ferric heme.
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Affiliation(s)
- Mohammad Aarabi
- Department of Chemistry, University of Isfahan, 81746-73441 Isfahan, Iran.
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26
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McQuarters AB, Blaesi EJ, Kampf JW, Alp EE, Zhao J, Hu M, Krebs C, Lehnert N. Synthetic Model Complex of the Key Intermediate in Cytochrome P450 Nitric Oxide Reductase. Inorg Chem 2019; 58:1398-1413. [PMID: 30623648 DOI: 10.1021/acs.inorgchem.8b02947] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Fungal denitrification plays a crucial role in the nitrogen cycle and contributes to the total N2O emission from agricultural soils. Here, cytochrome P450 NO reductase (P450nor) reduces two NO to N2O using a single heme site. Despite much research, the exact nature of the critical "Intermediate I" responsible for the key N-N coupling step in P450nor is unknown. This species likely corresponds to a Fe-NHOH-type intermediate with an unknown electronic structure. Here we report a new strategy to generate a model system for this intermediate, starting from the iron(III) methylhydroxylamide complex [Fe(3,5-Me-BAFP)(NHOMe)] (1), which was fully characterized by 1H NMR, UV-vis, electron paramagnetic resonance, and vibrational spectroscopy (rRaman and NRVS). Our data show that 1 is a high-spin ferric complex with an N-bound hydroxylamide ligand that is strongly coordinated (Fe-N distance, 1.918 Å; Fe-NHOMe stretch, 558 cm-1). Simple one-electron oxidation of 1 at -80 °C then cleanly generates the first model system for Intermediate I, [Fe(3,5-Me-BAFP)(NHOMe)]+ (1+). UV-vis, resonance Raman, and Mössbauer spectroscopies, in comparison to the chloro analogue [Fe(3,5-Me-BAFP)(Cl)]+, demonstrate that 1+ is best described as an FeIII-(NHOMe)• complex with a bound NHOMe radical. Further reactivity studies show that 1+ is highly reactive toward NO, a reaction that likely proceeds via N-N bond formation, following a radical-radical-type coupling mechanism. Our results therefore provide experimental evidence, for the first time, that an FeIII-(NHOMe)• electronic structure is indeed a reasonable electronic description for Intermediate I and that this electronic structure is advantageous for P450nor catalysis because it can greatly facilitate N-N bond formation and, ultimately, N2O generation.
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Affiliation(s)
- Ashley B McQuarters
- Department of Chemistry and Department of Biophysics , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | - Elizabeth J Blaesi
- Department of Chemistry and Department of Biochemistry and Molecular Biology , The Pennsylvania State University , University Park , Pennsylvania 16802 , United States
| | - Jeff W Kampf
- Department of Chemistry and Department of Biophysics , University of Michigan , Ann Arbor , Michigan 48109 , United States
| | - E Ercan Alp
- Advanced Photon Source (APS) , Argonne National Laboratory (ANL) , Argonne , Illinois 60439 , United States
| | - Jiyong Zhao
- Advanced Photon Source (APS) , Argonne National Laboratory (ANL) , Argonne , Illinois 60439 , United States
| | - Michael Hu
- Advanced Photon Source (APS) , Argonne National Laboratory (ANL) , Argonne , Illinois 60439 , 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 and Department of Biophysics , University of Michigan , Ann Arbor , Michigan 48109 , United States
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Amanullah S, Saha P, Saha R, Dey A. Synthetic Iron Porphyrins for Probing the Differences in the Electronic Structures of Heme a3, Heme d, and Heme d1. Inorg Chem 2018; 58:152-164. [DOI: 10.1021/acs.inorgchem.8b02063] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Sk Amanullah
- Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Kolkata 700032, India
| | - Paramita Saha
- Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Kolkata 700032, India
| | - Rajat Saha
- Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Kolkata 700032, India
| | - Abhishek Dey
- Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Kolkata 700032, India
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28
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Dey A, Confer AM, Vilbert AC, Moënne-Loccoz P, Lancaster KM, Goldberg DP. A Nonheme Sulfur-Ligated {FeNO} 6 Complex and Comparison with Redox-Interconvertible {FeNO} 7 and {FeNO} 8 Analogues. Angew Chem Int Ed Engl 2018; 57:13465-13469. [PMID: 30125450 DOI: 10.1002/anie.201806146] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Indexed: 01/23/2023]
Abstract
A nonheme {FeNO}6 complex, [Fe(NO)(N3PyS)]2+ , was synthesized by reversible, one-electron oxidation of an {FeNO}7 analogue. This complex completes the first known series of sulfur-ligated {FeNO}6-8 complexes. All three {FeNO}6-8 complexes are readily interconverted by one-electron oxidation/reduction. A comparison of spectroscopic data (UV/Vis, NMR, IR, Mössbauer, X-ray absorption) provides a complete picture of the electronic and structural changes that occur upon {FeNO}6 -{FeNO}8 interconversion. Dissociation of NO from the new {FeNO}6 complex is shown to be controlled by solvent, temperature, and photolysis, which is rare for a sulfur-ligated {FeNO}6 species.
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Affiliation(s)
- Aniruddha Dey
- Department of Chemistry, The Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Alex M Confer
- Department of Chemistry, The Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Avery C Vilbert
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - Pierre Moënne-Loccoz
- Division of Environmental and Biomolecular Systems, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Kyle M Lancaster
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853, USA
| | - David P Goldberg
- Department of Chemistry, The Johns Hopkins University, Baltimore, MD, 21218, USA
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29
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Dey A, Confer AM, Vilbert AC, Moënne‐Loccoz P, Lancaster KM, Goldberg DP. A Nonheme Sulfur‐Ligated {FeNO}
6
Complex and Comparison with Redox‐Interconvertible {FeNO}
7
and {FeNO}
8
Analogues. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201806146] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Aniruddha Dey
- Department of Chemistry The Johns Hopkins University Baltimore MD 21218 USA
| | - Alex M. Confer
- Department of Chemistry The Johns Hopkins University Baltimore MD 21218 USA
| | - Avery C. Vilbert
- Department of Chemistry and Chemical Biology Cornell University Ithaca NY 14853 USA
| | - Pierre Moënne‐Loccoz
- Division of Environmental and Biomolecular Systems Oregon Health and Science University Portland OR 97239 USA
| | - Kyle M. Lancaster
- Department of Chemistry and Chemical Biology Cornell University Ithaca NY 14853 USA
| | - David P. Goldberg
- Department of Chemistry The Johns Hopkins University Baltimore MD 21218 USA
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30
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Speelman AL, White CJ, Zhang B, Alp EE, Zhao J, Hu M, Krebs C, Penner-Hahn J, Lehnert N. Non-heme High-Spin {FeNO} 6-8 Complexes: One Ligand Platform Can Do It All. J Am Chem Soc 2018; 140:11341-11359. [PMID: 30107126 DOI: 10.1021/jacs.8b06095] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Heme and non-heme iron-nitrosyl complexes are important intermediates in biology. While there are numerous examples of low-spin heme iron-nitrosyl complexes in different oxidation states, much less is known about high-spin (hs) non-heme iron-nitrosyls in oxidation states other than the formally ferrous NO adducts ({FeNO}7 in the Enemark-Feltham notation). In this study, we present a complete series of hs-{FeNO}6-8 complexes using the TMG3tren coligand. Redox transformations from the hs-{FeNO}7 complex [Fe(TMG3tren)(NO)]2+ to its {FeNO}6 and {FeNO}8 analogs do not alter the coordination environment of the iron center, allowing for detailed comparisons between these species. Here, we present new MCD, NRVS, XANES/EXAFS, and Mössbauer data, demonstrating that these redox transformations are metal based, which allows us to access hs-Fe(II)-NO-, Fe(III)-NO-, and Fe(IV)-NO- complexes. Vibrational data, analyzed by NCA, directly quantify changes in Fe-NO bonding along this series. Optical data allow for the identification of a "spectator" charge-transfer transition that, together with Mössbauer and XAS data, directly monitors the electronic changes of the Fe center. Using EXAFS, we are also able to provide structural data for all complexes. The magnetic properties of the complexes are further analyzed (from magnetic Mössbauer). The properties of our hs-{FeNO}6-8 complexes are then contrasted to corresponding, low-spin iron-nitrosyl complexes where redox transformations are generally NO centered. The hs-{FeNO}8 complex can further be protonated by weak acids, and the product of this reaction is characterized. Taken together, these results provide unprecedented insight into the properties of biologically relevant non-heme iron-nitrosyl complexes in three relevant oxidation states.
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Affiliation(s)
- Amy L Speelman
- Department of Chemistry and Department of Biophysics , University of Michigan , Ann Arbor , Michigan 48109-1055 , United States
| | - Corey J White
- Department of Chemistry and Department of Biophysics , 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
| | - E Ercan Alp
- Advanced Photon Source , Argonne National Laboratory , Argonne , Illinois 60439 , United States
| | - Jiyong Zhao
- Advanced Photon Source , Argonne National Laboratory , Argonne , Illinois 60439 , United States
| | - Michael Hu
- Advanced Photon Source , Argonne National Laboratory , Argonne , Illinois 60439 , United States
| | - Carsten Krebs
- Department of Chemistry and Department of Biochemistry and Molecular Biology , The Pennsylvania State University , University Park , Pennsylvania 16802 , United States
| | - James Penner-Hahn
- Department of Chemistry and Department of Biophysics , University of Michigan , Ann Arbor , Michigan 48109-1055 , United States
| | - Nicolai Lehnert
- Department of Chemistry and Department of Biophysics , University of Michigan , Ann Arbor , Michigan 48109-1055 , United States
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31
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Hong S, Yan JJ, Karmalkar DG, Sutherlin KD, Kim J, Lee YM, Goo Y, Mascharak PK, Hedman B, Hodgson KO, Karlin KD, Solomon EI, Nam W. A mononuclear nonheme {FeNO} 6 complex: synthesis and structural and spectroscopic characterization. Chem Sci 2018; 9:6952-6960. [PMID: 30210769 PMCID: PMC6124912 DOI: 10.1039/c8sc01962b] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 07/18/2018] [Indexed: 01/19/2023] Open
Abstract
While the synthesis and characterization of {FeNO}7,8,9 complexes have been well documented in heme and nonheme iron models, {FeNO}6 complexes have been less clearly understood. Herein, we report the synthesis and structural and spectroscopic characterization of mononuclear nonheme {FeNO}6 and iron(iii)-nitrito complexes bearing a tetraamido macrocyclic ligand (TAML), such as [(TAML)FeIII(NO)]- and [(TAML)FeIII(NO2)]2-, respectively. First, direct addition of NO(g) to [FeIII(TAML)]- results in the formation of [(TAML)FeIII(NO)]-, which is sensitive to moisture and air. The spectroscopic data of [(TAML)FeIII(NO)]-, such as 1H nuclear magnetic resonance and X-ray absorption spectroscopies, combined with computational study suggest the neutral nature of nitric oxide with a diamagnetic Fe center (S = 0). We also provide alternative pathways for the generation of [(TAML)FeIII(NO)]-, such as the iron-nitrite reduction triggered by protonation in the presence of ferrocene, which acts as an electron donor, and the photochemical iron-nitrite reduction. To the best of our knowledge, the present study reports the first photochemical nitrite reduction in nonheme iron models.
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Affiliation(s)
- Seungwoo Hong
- Department of Chemistry and Nano Science , Ewha Womans University , Seoul 03760 , Korea . .,Department of Chemistry , Sookmyung Women's University , Seoul 04310 , Korea
| | - James J Yan
- Department of Chemistry , Stanford University , Stanford , California 94305 , USA .
| | - Deepika G Karmalkar
- Department of Chemistry and Nano Science , Ewha Womans University , Seoul 03760 , Korea .
| | - Kyle D Sutherlin
- Department of Chemistry , Stanford University , Stanford , California 94305 , USA .
| | - Jin Kim
- Department of Chemistry and Nano Science , Ewha Womans University , Seoul 03760 , Korea .
| | - Yong-Min Lee
- Department of Chemistry and Nano Science , Ewha Womans University , Seoul 03760 , Korea .
| | - Yire Goo
- Department of Chemistry and Nano Science , Ewha Womans University , Seoul 03760 , Korea .
| | - Pradip K Mascharak
- Department of Chemistry and Biochemistry , University of California , Santa Cruz , California 95064 , USA
| | - Britt Hedman
- Stanford Synchrotron Radiation Lightsource , SLAC National Accelerator Laboratory , Stanford University , California 94025 , USA . ;
| | - Keith O Hodgson
- Department of Chemistry , Stanford University , Stanford , California 94305 , USA . .,Stanford Synchrotron Radiation Lightsource , SLAC National Accelerator Laboratory , Stanford University , California 94025 , USA . ;
| | - Kenneth D Karlin
- Department of Chemistry , The Johns Hopkins University , Baltimore , Maryland 21218 , USA .
| | - Edward I Solomon
- Department of Chemistry , Stanford University , Stanford , California 94305 , USA . .,Stanford Synchrotron Radiation Lightsource , SLAC National Accelerator Laboratory , Stanford University , California 94025 , USA . ;
| | - Wonwoo Nam
- Department of Chemistry and Nano Science , Ewha Womans University , Seoul 03760 , Korea . .,School of Chemistry and Chemical Engineering , Shaanxi Normal University , Xi'an 710119 , P. R. China
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32
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Zink JR, Abucayon EG, Ramuglia AR, Fadamin A, Eilers JE, Richter‐Addo GB, Shaw MJ. Electrochemical Investigation of the Kinetics of Chloride Substitution upon Reduction of [Ru(porphyrin)(NO)Cl] Complexes in Tetrahydrofuran. ChemElectroChem 2017. [DOI: 10.1002/celc.201701001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Jeremy R. Zink
- Department of Chemistry Southern Illinois University Edwardsville Box 1652 Edwardsville, Illinois 62026 USA
- Department of Chemistry and Biochemistry University of Oklahoma 101 Stephenson Parkway Norman, Oklahoma 73019 USA
| | - Erwin G. Abucayon
- Department of Chemistry and Biochemistry University of Oklahoma 101 Stephenson Parkway Norman, Oklahoma 73019 USA
| | - Anthony R. Ramuglia
- Department of Chemistry Southern Illinois University Edwardsville Box 1652 Edwardsville, Illinois 62026 USA
| | - Arghavan Fadamin
- Department of Chemistry Southern Illinois University Edwardsville Box 1652 Edwardsville, Illinois 62026 USA
| | - James E. Eilers
- Department of Chemistry Southern Illinois University Edwardsville Box 1652 Edwardsville, Illinois 62026 USA
| | - George B. Richter‐Addo
- Department of Chemistry and Biochemistry University of Oklahoma 101 Stephenson Parkway Norman, Oklahoma 73019 USA
| | - Michael J. Shaw
- Department of Chemistry Southern Illinois University Edwardsville Box 1652 Edwardsville, Illinois 62026 USA
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