1
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De Simone G, di Masi A, Sbardella D, Ascenzi P, Coletta M. Nitric Oxide Binding Geometry in Heme-Proteins: Relevance for Signal Transduction. Antioxidants (Basel) 2024; 13:666. [PMID: 38929104 PMCID: PMC11201058 DOI: 10.3390/antiox13060666] [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: 04/12/2024] [Revised: 05/22/2024] [Accepted: 05/23/2024] [Indexed: 06/28/2024] Open
Abstract
Nitric oxide (NO) synthesis, signaling, and scavenging is associated to relevant physiological and pathological events. In all tissues and organs, NO levels and related functions are regulated at different levels, with heme proteins playing pivotal roles. Here, we focus on the structural changes related to the different binding modes of NO to heme-Fe(II), as well as the modulatory effects of this diatomic messenger on heme-protein functions. Specifically, the ability of heme proteins to bind NO at either the distal or proximal side of the heme and the transient interchanging of the binding site is reported. This sheds light on the regulation of O2 supply to tissues with high metabolic activity, such as the retina, where a precise regulation of blood flow is necessary to meet the demand of nutrients.
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Affiliation(s)
- Giovanna De Simone
- Dipartimento di Scienze, Università degli Studi Roma Tre, 00146 Rome, Italy; (G.D.S.); (A.d.M.)
| | - Alessandra di Masi
- Dipartimento di Scienze, Università degli Studi Roma Tre, 00146 Rome, Italy; (G.D.S.); (A.d.M.)
- Centro Linceo Interdisciplinare “Beniamino Segre”, Accademia dei Lincei, 00165 Rome, Italy
| | | | - Paolo Ascenzi
- Dipartimento di Scienze, Università degli Studi Roma Tre, 00146 Rome, Italy; (G.D.S.); (A.d.M.)
- Accademia Nazionale dei Lincei, 00165 Rome, Italy
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2
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Cole JM, Gosztola DJ, Velazquez-Garcia JDJ. Structural Capture of η 1-OSO to η 2-(OS)O Coordination Isomerism in a New Ruthenium-Based SO 2-Linkage Photoisomer That Exhibits Single-Crystal Optical Actuation. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2022; 126:6047-6059. [PMID: 35573119 PMCID: PMC9098168 DOI: 10.1021/acs.jpcc.2c00170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Revised: 03/11/2022] [Indexed: 06/15/2023]
Abstract
Recent discoveries of a range of single-crystal optical actuators are feeding a new form of materials chemistry, given their broad range of potential applications, from light-induced molecular motors to light sensors and optical-memory media. A series of ruthenium-based coordination complexes that exhibit sulfur dioxide linkage photoisomerization is of particular interest because they exhibit single-crystal optical actuation via either optical switching or nano-optomechanical transduction processes. We report the discovery of a new complex in this series of chemicals, [Ru(SO2)(NH3)4(3-fluoropyridine)]tosylate2 (1), which forms an η1-OSO photoisomer with 70% photoconversion upon the application of 505 nm light. The uncoordinated oxygen atom in this η1-OSO photoisomer impinges on one of the arene rings in a neighboring tosylate counter ion of 1 just enough that incipient nano-optomechanical transduction is observed. The structure and optical properties of this actuator are characterized via in situ light-induced single-crystal X-ray diffraction (photocrystallography), single-crystal optical absorption spectroscopy and microscopy, as well as single-crystal Raman spectroscopy. These materials-characterization methods were also used to track thermally induced reverse isomerization processes in 1. One of these processes involves an η1-OSO to η2-(OS)O transition, which was found to proceed sufficiently slowly at 110 K that its structural mechanism could be determined via a time sequence of photocrystallography experiments. The resulting data allowed us to structurally capture the transition, which was shown to occur via a form of coordination isomerism. Our newfound knowledge about this structural mechanism will aid the molecular design of new [RuSO2] complexes with functional applications.
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Affiliation(s)
- Jacqueline M. Cole
- Cavendish
Laboratory, Department of Physics, University
of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, U.K.
- ISIS
Neutron and Muon Source, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot OX11 0QX, U.K.
- Center
for Nanoscale Materials, Argonne National
Laboratory, 9700 S Cass Avenue, Lemont, Illinois 60439, United
States
| | - David J. Gosztola
- Center
for Nanoscale Materials, Argonne National
Laboratory, 9700 S Cass Avenue, Lemont, Illinois 60439, United
States
| | - Jose de J. Velazquez-Garcia
- Cavendish
Laboratory, Department of Physics, University
of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, U.K.
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3
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Ahmed E, Chizhik S, Sidelnikov A, Boldyreva E, Naumov P. Relating Excited States to the Dynamics of Macroscopic Strain in Photoresponsive Crystals. Inorg Chem 2022; 61:3573-3585. [PMID: 35170305 DOI: 10.1021/acs.inorgchem.1c03607] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Exposure of a photoreactive single crystal to light with a wavelength offset from its absorption maximum can have two distinct effects. The first is the "direct" effect, wherein the excited state generated in individual chemical species is influenced. The second is the "indirect" effect, which describes the penetration of light into the crystal and hence the spatial propagation and completeness of transformation. We illustrate using the nitro-nitrito isomerization of [Co(NH3)5NO2]Cl(NO3) as an example that the direct and indirect effects can be independently determined. This is achieved by comparing the dynamics of macroscopic crystal deformation (bending curvature and crystal elongation) induced by the photochemical reaction when irradiating a crystal at the absorption maximum and at different band edges (above or below the maximum) of the same band. Quantitative description of the macroscopic strain dynamics in comparison with experiments allowed us to suggest that irradiation at different tails of the same absorption band causes isomerization to proceed via different excited states and an additional photochemical reaction (presumably, reverse nitrito-nitro isomerization) can occur on irradiation at the ligand-field band edges.
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Affiliation(s)
- Ejaz Ahmed
- Smart Materials Lab, New York University, Abu Dhabi, POB 129188, Abu Dhabi 00000, U.A.E
| | - Stanislav Chizhik
- Institute of Solid State Chemistry and Mechanochemistry SB RAS, ul. Kutateladze, 18, Novosibirsk 630128, Russian Federation.,Novosibirsk State University, ul. Pirogova, 2, Novosibirsk 630090, Russian Federation
| | - Anatoly Sidelnikov
- Institute of Solid State Chemistry and Mechanochemistry SB RAS, ul. Kutateladze, 18, Novosibirsk 630128, Russian Federation
| | - Elena Boldyreva
- Novosibirsk State University, ul. Pirogova, 2, Novosibirsk 630090, Russian Federation.,Boreskov Institute of Catalysis SB RAS, pr. Lavrentieva, 5, Novosibirsk 630090, Russian Federation
| | - Panče Naumov
- Smart Materials Lab, New York University, Abu Dhabi, POB 129188, Abu Dhabi 00000, U.A.E
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4
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Cole JM, Gosztola DJ, Velazquez-Garcia JDJ. Nanooptomechanical Transduction in a Single Crystal with 100% Photoconversion. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2021; 125:8907-8915. [PMID: 34084264 PMCID: PMC8162413 DOI: 10.1021/acs.jpcc.1c02457] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/02/2021] [Indexed: 06/12/2023]
Abstract
Materials that exhibit nanooptomechanical transduction in their single-crystal form have prospective use in light-driven molecular machinery, nanotechnology, and quantum computing. Linkage photoisomerization is typically the source of such transduction in coordination complexes, although the isomers tend to undergo only partial photoconversion. We present a nanooptomechanical transducer, trans-[Ru(SO2)(NH3)4(3-bromopyridine)]tosylate2, whose S-bound η1-SO2 isomer fully converts into an O-bound η1-OSO photoisomer that is metastable while kept at 100 K. Its 100% photoconversion is confirmed structurally via photocrystallography, while single-crystal optical absorption and Raman spectroscopies reveal its metal-to-ligand charge-transfer and temperature-dependent characteristics. This perfect optical switching affords the material good prospects for nanooptomechanical transduction with single-photon control.
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Affiliation(s)
- Jacqueline M. Cole
- Cavendish
Laboratory, Department of Physics, University
of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0HE, U.K.
- ISIS
Neutron and Muon Source, STFC Rutherford
Appleton Laboratory, Harwell Science and Innovation Campus, Didcot OX11 0QX, U.K.
- Department
of Chemical Engineering and Biotechnology, University of Cambridge, West Cambridge Site, Philippa Fawcett Drive, Cambridge CB3 0AS, U.K.
- Argonne
National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439, United
States
| | - David J. Gosztola
- Argonne
National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439, United
States
| | - Jose de J. Velazquez-Garcia
- Cavendish
Laboratory, Department of Physics, University
of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0HE, U.K.
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5
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Kim DH, Ringe S, Kim H, Kim S, Kim B, Bae G, Oh HS, Jaouen F, Kim W, Kim H, Choi CH. Selective electrochemical reduction of nitric oxide to hydroxylamine by atomically dispersed iron catalyst. Nat Commun 2021; 12:1856. [PMID: 33767159 PMCID: PMC7994811 DOI: 10.1038/s41467-021-22147-7] [Citation(s) in RCA: 68] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Accepted: 02/19/2021] [Indexed: 12/03/2022] Open
Abstract
Electrocatalytic conversion of nitrogen oxides to value-added chemicals is a promising strategy for mitigating the human-caused unbalance of the global nitrogen-cycle, but controlling product selectivity remains a great challenge. Here we show iron-nitrogen-doped carbon as an efficient and durable electrocatalyst for selective nitric oxide reduction into hydroxylamine. Using in operando spectroscopic techniques, the catalytic site is identified as isolated ferrous moieties, at which the rate for hydroxylamine production increases in a super-Nernstian way upon pH decrease. Computational multiscale modelling attributes the origin of unconventional pH dependence to the redox active (non-innocent) property of NO. This makes the rate-limiting NO adsorbate state more sensitive to surface charge which varies with the pH-dependent overpotential. Guided by these fundamental insights, we achieve a Faradaic efficiency of 71% and an unprecedented production rate of 215 μmol cm-2 h-1 at a short-circuit mode in a flow-type fuel cell without significant catalytic deactivation over 50 h operation.
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Affiliation(s)
- Dong Hyun Kim
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, Republic of Korea
| | - Stefan Ringe
- Department of Energy Science and Engineering, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea
| | - Haesol Kim
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, Republic of Korea
| | - Sejun Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Bupmo Kim
- Department of Chemical Engineering, Pohang University of Science and Technology, Pohang, Republic of Korea
| | - Geunsu Bae
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, Republic of Korea
| | - Hyung-Suk Oh
- Clean Energy Research Center, Korea Institute of Science and Technology, Seoul, Republic of Korea
| | - Frédéric Jaouen
- ICGM, Université de Montpellier, CNRS, ENSCM, Montpellier, France
| | - Wooyul Kim
- Department of Chemical and Biological Engineering, Sookmyung Women's University, Seoul, Republic of Korea.
| | - Hyungjun Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea.
| | - Chang Hyuck Choi
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, Republic of Korea.
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6
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Yoon H, Park S, Lim M. Photorelease Dynamics of Nitric Oxide from Cysteine-Bound Roussin's Red Ester. J Phys Chem Lett 2020; 11:3198-3202. [PMID: 32250631 DOI: 10.1021/acs.jpclett.0c00739] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Nitric oxide (NO) can either boost or impede the growth of cancer cells depending on its concentration. Therefore, any anticancer treatment using NO requires precisely controlled NO administration to the target cells in terms of dosage and timing. In this context, photochemically activated NO donors were actively explored, but their detailed NO-releasing dynamics, which is crucial for their use, is not known yet. We determined detailed photoexcitation dynamics of a stable, nontoxic, and water-soluble NO precursor, cysteine-bound Roussin's Red Ester (Cys-RRE), including secondary reactions of the nascent photoproducts. The primary quantum yields of the NO dissociation from the photoexcited Cys-RRE were found to be 24-54% depending on the excitation wavelength; however, the geminate rebinding of NO with the nascent radical reduced the level of biologically available NO to as low as 12%. Such information is useful to achieve efficient NO delivery to practical chemical and biological targets.
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Affiliation(s)
- Hojeong Yoon
- Department of Chemistry and Chemistry Institute for Functional Materials, Pusan National University, Busan 46241, Korea
| | - Seongchul Park
- Department of Chemistry and Chemistry Institute for Functional Materials, Pusan National University, Busan 46241, Korea
| | - Manho Lim
- Department of Chemistry and Chemistry Institute for Functional Materials, Pusan National University, Busan 46241, Korea
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7
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Diamantis P, Hage KE, Meuwly M. Effect of Single-Point Mutations on Nitric Oxide Rebinding and the Thermodynamic Stability of Myoglobin. J Phys Chem B 2019; 123:1961-1972. [PMID: 30724565 DOI: 10.1021/acs.jpcb.8b11454] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The effect of single amino acid mutations on the rebinding dynamics of nitrogen monoxide (NO) to myoglobin is investigated using reactive molecular dynamics simulations. In particular, mutations of residues surrounding the heme-active site (Leu29, His64, Val68) were considered. Consistent with experiments, all mutations studied here have a significant effect on the kinetics of the NO-rebinding process, which consists of a rapid (several 10 ps) and a slow (100s of ps) time scale. For all modifications considered, the time scales and rebinding fractions agree to within a few percents with results from experiments by adjusting one single, physically meaningful, conformationally averaged quantity: the asymptotic energy separation between the NO-bound (2A) and photodissociated (4A) states. It is furthermore shown that the thermodynamic stability of wild-type versus mutant Mb for the ligand-free and ligand-bound variants of the protein can be described by the same computational model. Therefore, ligand kinetics and thermodynamics are related in a direct fashion akin to Φ-value analysis, which establishes a relationship between protein folding rates and thermal stability of proteins.
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Affiliation(s)
- Polydefkis Diamantis
- Department of Chemistry , University of Basel , Klingelbergstrasse 80 , 4056 Basel , Switzerland
| | - Krystel El Hage
- Department of Chemistry , University of Basel , Klingelbergstrasse 80 , 4056 Basel , Switzerland
| | - Markus Meuwly
- Department of Chemistry , University of Basel , Klingelbergstrasse 80 , 4056 Basel , Switzerland.,Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
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8
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In-Iam A, Wolf M, Wilfer C, Schaniel D, Woike T, Klüfers P. {FeNO}7
-Type Halogenido Nitrosyl Ferrates: Syntheses, Bonding, and Photoinduced Linkage Isomerism. Chemistry 2018; 25:1304-1325. [DOI: 10.1002/chem.201804565] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 10/15/2018] [Indexed: 11/08/2022]
Affiliation(s)
- Areenan In-Iam
- Department of Chemistry; Ludwig-Maximilians-Universitaet; Butenandtstrasse 5-13, Haus D München 81377 Germany
| | - Markus Wolf
- Department of Chemistry; Ludwig-Maximilians-Universitaet; Butenandtstrasse 5-13, Haus D München 81377 Germany
| | - Claudia Wilfer
- Department of Chemistry; Ludwig-Maximilians-Universitaet; Butenandtstrasse 5-13, Haus D München 81377 Germany
| | - Dominik Schaniel
- Laboratoire de Cristallographie, Résonance Magnétique et, Modélisation (CRM2); Université de Lorraine & CNRS; Boulevard des Aiguillettes, BP 70239 Vandoeuvre les Nancy 54506 France
| | - Theo Woike
- Laboratoire de Cristallographie, Résonance Magnétique et, Modélisation (CRM2); Université de Lorraine & CNRS; Boulevard des Aiguillettes, BP 70239 Vandoeuvre les Nancy 54506 France
| | - Peter Klüfers
- Department of Chemistry; Ludwig-Maximilians-Universitaet; Butenandtstrasse 5-13, Haus D München 81377 Germany
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9
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Wang B, Shi Y, Tejero J, Powell SM, Thomas LM, Gladwin MT, Shiva S, Zhang Y, Richter-Addo GB. Nitrosyl Myoglobins and Their Nitrite Precursors: Crystal Structural and Quantum Mechanics and Molecular Mechanics Theoretical Investigations of Preferred Fe -NO Ligand Orientations in Myoglobin Distal Pockets. Biochemistry 2018; 57:4788-4802. [PMID: 29999305 PMCID: PMC6474360 DOI: 10.1021/acs.biochem.8b00542] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The globular dioxygen binding heme protein myoglobin (Mb) is present in several species. Its interactions with the simple nitrogen oxides, namely, nitric oxide (NO) and nitrite, have been known for decades, but the physiological relevance has only recently become more fully appreciated. We previously reported the O-nitrito mode of binding of nitrite to ferric horse heart wild-type (wt) MbIII and human hemoglobin. We have expanded on this work and report the interactions of nitrite with wt sperm whale (sw) MbIII and its H64A, H64Q, and V68A/I107Y mutants whose dissociation constants increase in the following order: H64Q < wt < V68A/I107Y < H64A. We also report their X-ray crystal structures that reveal the O-nitrito mode of binding of nitrite to these derivatives. The MbII-mediated reductions of nitrite to NO and structural data for the wt and mutant MbII-NOs are described. We show that their FeNO orientations vary with distal pocket identity, with the FeNO moieties pointing toward the hydrophobic interiors when the His64 residue is present but toward the hydrophilic exterior when this His64 residue is absent in this set of mutants. This correlates with the nature of H-bonding to the bound NO ligand (nitrosyl O vs N atom). Quantum mechanics and hybrid quantum mechanics and molecular mechanics calculations help elucidate the origin of the experimentally preferred NO orientations. In a few cases, the calculations reproduce the experimentally observed orientations only when the whole protein is taken into consideration.
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Affiliation(s)
- Bing Wang
- Price Family Foundation Institute of Structural Biology, and Department of Chemistry and Biochemistry,
University of Oklahoma, 101 Stephenson Parkway, Norman, OK 73019
| | - Yelu Shi
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Castle Point on Hudson,
Hoboken, NJ 07030
| | - Jesús Tejero
- Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh School of Medicine, 3550 Terrace
Street, Pittsburgh, PA 15261
| | - Samantha M. Powell
- Price Family Foundation Institute of Structural Biology, and Department of Chemistry and Biochemistry,
University of Oklahoma, 101 Stephenson Parkway, Norman, OK 73019
| | - Leonard M. Thomas
- Price Family Foundation Institute of Structural Biology, and Department of Chemistry and Biochemistry,
University of Oklahoma, 101 Stephenson Parkway, Norman, OK 73019
| | - Mark T. Gladwin
- Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh School of Medicine, 3550 Terrace
Street, Pittsburgh, PA 15261
| | - Sruti Shiva
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, 200 Lothrop Street, Pittsburgh, PA
15213
| | - Yong Zhang
- Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Castle Point on Hudson,
Hoboken, NJ 07030
| | - George B. Richter-Addo
- Price Family Foundation Institute of Structural Biology, and Department of Chemistry and Biochemistry,
University of Oklahoma, 101 Stephenson Parkway, Norman, OK 73019
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10
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Hidden role of intermolecular proton transfer in the anomalously diffuse vibrational spectrum of a trapped hydronium ion. Proc Natl Acad Sci U S A 2017; 114:E4706-E4713. [PMID: 28566495 DOI: 10.1073/pnas.1705089114] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
We report the vibrational spectra of the hydronium and methyl-ammonium ions captured in the C3v binding pocket of the 18-crown-6 ether ionophore. Although the NH stretching bands of the CH3NH3+ ion are consistent with harmonic expectations, the OH stretching bands of H3O+ are surprisingly broad, appearing as a diffuse background absorption with little intensity modulation over 800 cm-1 with an onset ∼400 cm-1 below the harmonic prediction. This structure persists even when only a single OH group is present in the HD2O+ isotopologue, while the OD stretching region displays a regular progression involving a soft mode at about 85 cm-1 These results are rationalized in a vibrationally adiabatic (VA) model in which the motion of the H3O+ ion in the crown pocket is strongly coupled with its OH stretches. In this picture, H3O+ resides in the center of the crown in the vibrational zero-point level, while the minima in the VA potentials associated with the excited OH vibrational states are shifted away from the symmetrical configuration displayed by the ground state. Infrared excitation between these strongly H/D isotope-dependent VA potentials then accounts for most of the broadening in the OH stretching manifold. Specifically, low-frequency motions involving concerted motions of the crown scaffold and the H3O+ ion are driven by a Franck-Condon-like mechanism. In essence, vibrational spectroscopy of these systems can be viewed from the perspective of photochemical interconversion between transient, isomeric forms of the complexes corresponding to the initial stage of intermolecular proton transfer.
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11
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Soloviov M, Das AK, Meuwly M. Strukturelle Interpretation metastabiler Zustände in Myoglobin-NO. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201604552] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Maksym Soloviov
- Departement für Chemie; Universität Basel; Klingelbergstraße 80 4056 Basel Schweiz
| | - Akshaya K. Das
- Departement für Chemie; Universität Basel; Klingelbergstraße 80 4056 Basel Schweiz
| | - Markus Meuwly
- Departement für Chemie; Universität Basel; Klingelbergstraße 80 4056 Basel Schweiz
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12
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Soloviov M, Das AK, Meuwly M. Structural Interpretation of Metastable States in Myoglobin-NO. Angew Chem Int Ed Engl 2016; 55:10126-30. [DOI: 10.1002/anie.201604552] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Indexed: 01/08/2023]
Affiliation(s)
- Maksym Soloviov
- Department of Chemistry; University of Basel; Klingelbergstrasse 80 4056 Basel Switzerland
| | - Akshaya K. Das
- Department of Chemistry; University of Basel; Klingelbergstrasse 80 4056 Basel Switzerland
| | - Markus Meuwly
- Department of Chemistry; University of Basel; Klingelbergstrasse 80 4056 Basel Switzerland
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13
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Soloviov M, Meuwly M. Reproducing kernel potential energy surfaces in biomolecular simulations: Nitric oxide binding to myoglobin. J Chem Phys 2016; 143:105103. [PMID: 26374062 DOI: 10.1063/1.4929527] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Multidimensional potential energy surfaces based on reproducing kernel-interpolation are employed to explore the energetics and dynamics of free and bound nitric oxide in myoglobin (Mb). Combining a force field description for the majority of degrees of freedom and the higher-accuracy representation for the NO ligand and the Fe out-of-plane motion allows for a simulation approach akin to a mixed quantum mechanics/molecular mechanics treatment. However, the kernel-representation can be evaluated at conventional force-field speed. With the explicit inclusion of the Fe-out-of-plane (Fe-oop) coordinate, the dynamics and structural equilibrium after photodissociation of the ligand are correctly described compared to experiment. Experimentally, the Fe-oop coordinate plays an important role for the ligand dynamics. This is also found here where the isomerization dynamics between the Fe-ON and Fe-NO state is significantly affected whether or not this co-ordinate is explicitly included. Although the Fe-ON conformation is metastable when considering only the bound (2)A state, it may disappear once the (4)A state is included. This explains the absence of the Fe-ON state in previous experimental investigations of MbNO.
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Affiliation(s)
- Maksym Soloviov
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
| | - Markus Meuwly
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
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14
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Yi J, Coppens P, Powell DR, Richter-Addo GB. Linkage Isomerization in Nitrosothiols (RSNOs): The X-ray Crystal Structure of an S-nitrosocysteine and DFT Analysis of its Metastable MS1 and MS2 Isomers. COMMENT INORG CHEM 2015. [DOI: 10.1080/02603594.2015.1095185] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Jun Yi
- Department of Biological Engineering, Nanjing University of Science and Technology, Nanjing, China
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma, USA
| | - Philip Coppens
- Department of Chemistry, State University of New York at Buffalo, Buffalo, New York, USA
| | - Douglas R. Powell
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma, USA
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15
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16
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Berto TC, Xu N, Lee SR, McNeil AJ, Alp EE, Zhao J, Richter-Addo GB, Lehnert N. Characterization of the Bridged Hyponitrite Complex {[Fe(OEP)]2(μ-N2O2)}: Reactivity of Hyponitrite Complexes and Biological Relevance. Inorg Chem 2014; 53:6398-414. [DOI: 10.1021/ic5002573] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Timothy C. Berto
- Department
of Chemistry and Department of Biophysics, University of Michigan, 930 N. University Avenue, Ann Arbor, Michigan 48109, United States
| | - Nan Xu
- Department
of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson
Parkway, Norman, Oklahoma 73019, United States
| | - Se Ryeon Lee
- Department
of Chemistry and Department of Biophysics, University of Michigan, 930 N. University Avenue, Ann Arbor, Michigan 48109, United States
| | - Anne J. McNeil
- Department
of Chemistry and Department of Biophysics, University of Michigan, 930 N. University Avenue, Ann Arbor, Michigan 48109, United States
| | - E. Ercan Alp
- Argonne National Laboratory, APS/XFD, 431/D003, Argonne, Illinois 60439, United States
| | - Jiyong Zhao
- Argonne National Laboratory, APS/XFD, 431/D003, Argonne, Illinois 60439, United States
| | - George B. Richter-Addo
- Department
of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson
Parkway, Norman, Oklahoma 73019, United States
| | - Nicolai Lehnert
- Department
of Chemistry and Department of Biophysics, University of Michigan, 930 N. University Avenue, Ann Arbor, Michigan 48109, United States
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Warren MR, Easun TL, Brayshaw SK, Deeth RJ, George MW, Johnson AL, Schiffers S, Teat SJ, Warren AJ, Warren JE, Wilson CC, Woodall CH, Raithby PR. Solid-state interconversions: unique 100 % reversible transformations between the ground and metastable states in single-crystals of a series of nickel(II) nitro complexes. Chemistry 2014; 20:5468-77. [PMID: 24644042 PMCID: PMC4164279 DOI: 10.1002/chem.201302053] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 02/17/2014] [Indexed: 11/19/2022]
Abstract
The solid-state, low-temperature linkage isomerism in a series of five square planar group 10 phosphino nitro complexes have been investigated by a combination of photocrystallographic experiments, Raman spectroscopy and computer modelling. The factors influencing the reversible solid-state interconversion between the nitro and nitrito structural isomers have also been investigated, providing insight into the dynamics of this process. The cis-[Ni(dcpe)(NO2)2] (1) and cis-[Ni(dppe)(NO2)2] (2) complexes show reversible 100 % interconversion between the η1-NO2 nitro isomer and the η1-ONO nitrito form when single-crystals are irradiated with 400 nm light at 100 K. Variable temperature photocrystallographic studies for these complexes established that the metastable nitrito isomer reverted to the ground-state nitro isomer at temperatures above 180 K. By comparison, the related trans complex [Ni(PCy3)2(NO2)2] (3) showed 82 % conversion under the same experimental conditions at 100 K. The level of conversion to the metastable nitrito isomers is further reduced when the nickel centre is replaced by palladium or platinum. Prolonged irradiation of the trans-[Pd(PCy3)2(NO2)2] (4) and trans-[Pt(PCy3)2(NO2)2] (5) with 400 nm light gives reversible conversions of 44 and 27 %, respectively, consistent with the slower kinetics associated with the heavier members of group 10. The mechanism of the interconversion has been investigated by theoretical calculations based on the model complex [Ni(dmpe)Cl(NO2)].
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Affiliation(s)
- Mark R Warren
- Department of Chemistry, University of Bath, Bath, BA2 7AY (UK); The Research Complex at Harwell, Rutherford Appleton Laboratory, Didcot, Oxon, OX11 0FA (UK)
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18
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Lima JMM, Silva VHC, Camargo LTFM, de Oliveira HCB, Camargo AJ. Theoretical investigation on ruthenium tetraazaporphyrin as potential nitric oxide carrier in biological systems. J Mol Model 2013; 19:1727-37. [DOI: 10.1007/s00894-012-1715-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Accepted: 11/27/2012] [Indexed: 12/01/2022]
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19
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Cazade PA, Huang J, Yosa J, Szymczak JJ, Meuwly M. Atomistic simulations of reactive processes in the gas- and condensed-phase. INT REV PHYS CHEM 2012. [DOI: 10.1080/0144235x.2012.694694] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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20
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Brayshaw SK, Easun TL, George MW, Griffin AME, Johnson AL, Raithby PR, Savarese TL, Schiffers S, Warren JE, Warren MR, Teat SJ. Photocrystallographic identification of metastable nitrito linkage isomers in a series of nickel(II) complexes. Dalton Trans 2012; 41:90-7. [PMID: 22012005 DOI: 10.1039/c1dt11379h] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Single crystal photocrystallographic experiments and solid state Raman spectroscopy have been used to determine the low temperature, metastable structures of the nickel(ii) nitrito complexes [Ni(aep)(2)(η(1)-ONO)(2)] 1#O (aep = 1-(2-aminoethyl)piperidine), [Ni(aem)(2)(η(1)-ONO)(2)] 2#O (aem = 1-(2-aminoethyl)morpholine), and [Ni(aepy)(2)(η(1)-ONO)(2)] 3#O (aepy = 1-(2-aminoethyl)pyrrolidine and where the #O denotes the oxygen-bound nitrito metastable molecule). These linkage isomers of the equivalent nitro complexes [Ni(aep)(2)(η(1)-NO(2))(2)] 1, [Ni(aem)(2)(η(1)-NO(2))(2)] 2 and [Ni(aepy)(2)(η(1)-NO(2))(2)] 3 are formed by LED irradiation at temperatures below 120 K. The behavior of the three complexes upon irradiation is generally similar, but some subtle differences have been observed. From the crystallographic studies all three complexes 1-3 exhibit the endo-nitrito linkage isomer upon irradiation, however, for 3# (a crystal structure that contains components of both 3 and 3#O) an exo-nitrito isomer is also observed. Under conditions of 90-100 K, with blue light, the conversion percentages to the nitrito isomers, 1#O, 2#O and 3#O were 16%, 22% and 30%, respectively. At temperatures below 110 K all three nitrito isomers were stable for over four hours but while 2#O and 3#O could be detected at temperatures down to 30 K, at temperatures below 60 K the metastable structure 1#O appeared to be quenched and only the nitro isomer 1 was identified in the crystal. The solid state Raman spectra for 1#, 2# and 3# confirmed the photocrystallographic results with the nitrito isomers being identified from the O-N-O deformation vibrations.
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Affiliation(s)
- Simon K Brayshaw
- Department of Chemistry, University of Bath, Claverton Down, Bath, UK BA2 7AY
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21
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Lanucara F, Chiavarino B, Crestoni ME, Scuderi D, Sinha RK, Maı̂tre P, Fornarini S. Naked Five-Coordinate FeIII(NO) Porphyrin Complexes: Vibrational and Reactivity Features. Inorg Chem 2011; 50:4445-52. [DOI: 10.1021/ic200073v] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Francesco Lanucara
- Dipartimento di Chimica e Tecnologie del Farmaco, Università di Roma “La Sapienza”, P.le A. Moro 5, I-00185, Roma, Italy
| | - Barbara Chiavarino
- Dipartimento di Chimica e Tecnologie del Farmaco, Università di Roma “La Sapienza”, P.le A. Moro 5, I-00185, Roma, Italy
| | - Maria Elisa Crestoni
- Dipartimento di Chimica e Tecnologie del Farmaco, Università di Roma “La Sapienza”, P.le A. Moro 5, I-00185, Roma, Italy
| | - Debora Scuderi
- Laboratoire de Chimie Physique, UMR8000 CNRS, Faculté des Sciences, Université Paris Sud, Bâtiment 350, 91405 Orsay Cedex, France
| | - Rajeev K. Sinha
- Laboratoire de Chimie Physique, UMR8000 CNRS, Faculté des Sciences, Université Paris Sud, Bâtiment 350, 91405 Orsay Cedex, France
| | - Philippe Maı̂tre
- Laboratoire de Chimie Physique, UMR8000 CNRS, Faculté des Sciences, Université Paris Sud, Bâtiment 350, 91405 Orsay Cedex, France
| | - Simonetta Fornarini
- Dipartimento di Chimica e Tecnologie del Farmaco, Università di Roma “La Sapienza”, P.le A. Moro 5, I-00185, Roma, Italy
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22
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Lynch MS, Cheng M, Van Kuiken BE, Khalil M. Probing the Photoinduced Metal−Nitrosyl Linkage Isomerism of Sodium Nitroprusside in Solution Using Transient Infrared Spectroscopy. J Am Chem Soc 2011; 133:5255-62. [DOI: 10.1021/ja110881n] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Michael S. Lynch
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Mark Cheng
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Benjamin E. Van Kuiken
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Munira Khalil
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
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23
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De Candia AG, Marcolongo JP, Etchenique R, Slep LD. Widely differing photochemical behavior in related octahedral {Ru-NO}6 compounds: intramolecular redox isomerism of the excited state controlling the photodelivery of NO. Inorg Chem 2010; 49:6925-30. [PMID: 20578716 DOI: 10.1021/ic100491g] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
trans-[(NC)Ru(py)(4)(mu-CN)Ru(py)(4)(NO)](3+) (py = pyridine) is a stable species in aqueous solution. It displays an intense absorption in the visible region of the spectrum (lambda(max) = 518 nm; epsilon(max) = 6100 M(-1) cm(-1)), which turns this compound into a promising agent for the photodelivery of NO. The quantum yield for the photodelivery process resulting from irradiation with 455 nm visible light was found experimentally to be (0.06 +/- 0.01) x 10(-3) mol einstein(-1), almost 3 orders of magnitude smaller than that in the closely related cis-[RuL(NH(3))(4)(mu-pz)Ru(bpy)(2)(NO)](5+) species (L = NH(3) or pyridine, pz = pyrazine, bpy = 2,2'-bipyridine; phi(NO) = 0.02-0.04 mol einstein(-1) depending on L) and also much smaller than the one in the mononuclear compound trans-[ClRu(py)(4)(NO)](2+) (phi(NO) = (1.63 +/- 0.04) x 10(-3) mol einstein(-1)). DFT computations provide an electronic structure picture of the photoactive excited states that helps to understand this apparently abnormal behavior.
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Affiliation(s)
- Ariel G De Candia
- Departamento de Química Inorgánica, Analítica y Química Física, INQUIMAE, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires-CONICET, 3er Piso, C1428EHA Buenos Aires, Argentina
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24
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Xu N, Yi J, Richter-Addo GB. Linkage isomerization in heme-NOx compounds: understanding NO, nitrite, and hyponitrite interactions with iron porphyrins. Inorg Chem 2010; 49:6253-66. [PMID: 20666385 DOI: 10.1021/ic902423v] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Nitric oxide (NO) and its derivatives such as nitrite and hyponitrite are biologically important species of relevance to human health. Much of their physiological relevance stems from their interactions with the iron centers in heme proteins. The chemical reactivities displayed by the heme-NOx species (NOx = NO, nitrite, hyponitrite) are a function of the binding modes of the NOx ligands. Hence, an understanding of the types of binding modes extant in heme-NOx compounds is important if we are to unravel the inherent chemical properties of these NOx metabolites. In this Forum Article, the experimentally characterized linkage isomers of heme-NOx models and proteins are presented and reviewed. Nitrosyl linkage isomers of synthetic iron and ruthenium porphyrins have been generated by photolysis at low temperatures and characterized by spectroscopy and density functional theory calculations. Nitrite linkage isomers in synthetic metalloporphyrin derivatives have been generated from photolysis experiments and in low-temperature matrices. In the case of nitrite adducts of heme proteins, both N and O binding have been determined crystallographically, and the role of the distal H-bonding residue in myoglobin in directing the O-binding mode of nitrite has been explored using mutagenesis. To date, only one synthetic metalloporphyrin complex containing a hyponitrite ligand (displaying an O-binding mode) has been characterized by crystallography. This is contrasted with other hyponitrite binding modes experimentally determined for coordination compounds and computationally for NO reductase enzymes. Although linkage isomerism in heme-NOx derivatives is still in its infancy, opportunities now exist for a detailed exploration of the existence and stabilities of the metastable states in both heme models and heme proteins.
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Affiliation(s)
- Nan Xu
- Department of Chemistry and Biochemistry, University of Oklahoma, 620 Parrington Oval, Norman, Oklahoma 73019, USA
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25
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Scheidt WR, Barabanschikov A, Pavlik JW, Silvernail NJ, Sage JT. Electronic structure and dynamics of nitrosyl porphyrins. Inorg Chem 2010; 49:6240-52. [PMID: 20666384 PMCID: PMC2919577 DOI: 10.1021/ic100261b] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Nitric oxide (NO) is a signaling molecule employed to regulate essential physiological processes. Thus, there is great interest in understanding the interaction of NO with heme, which is found at the active site of many proteins that recognize NO, as well as those involved in its creation and elimination. We summarize what we have learned from investigations of the structure, vibrational properties, and conformational dynamics of NO complexes with ferrous porphyrins, as well as computational investigations in support of these experimental studies. Multitemperature crystallographic data reveal variations in the orientational disorder of the nitrosyl ligand. In some cases, equilibria among NO orientations can be analyzed using the van't Hoff relationship and the free energy and enthalpy of the solid-state transitions evaluated experimentally. Density functional theory (DFT) calculations predict that intrinsic barriers to torsional rotation are smaller than thermal energies at physiological temperatures, and the coincidence of observed NO orientations with minima in molecular mechanics potentials indicates that nonbonded interactions with other chemical groups control the conformational freedom of the bound NO. In favorable cases, reduced disorder at low temperatures exposes subtle structural features including off-axis tilting of the Fe-NO bond and anisotropy of the equatorial Fe-N bonds. We also present the results of nuclear resonance vibrational spectroscopy measurements on oriented single crystals of [Fe(TPP)(NO)] and [Fe(TPP)(1-MeIm)(NO)]. These describe the anisotropic vibrational motion of iron in five- and six-coordinate heme-NO complexes and reveal vibrations of all Fe-ligand bonds as well as low-frequency molecular distortions associated with the doming of the heme upon ligand binding. A quantitative comparison with predicted frequencies, amplitudes, and directions facilitates identification of the vibrational modes but also suggests that commonly used DFT functionals are not fully successful at capturing the trans interaction between the axial NO and imidazole ligands. This supports previous conclusions that heme-NO complexes exhibit an unusual degree of variability with respect to the computational method, and we speculate that this variability hints at a genuine electronic instability that a protein can exploit to tune its reactivity. We anticipate that ongoing characterization of heme-NO complexes will deepen our understanding of their structure, dynamics, and reactivity.
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Affiliation(s)
- W. Robert Scheidt
- To whom correspondence should be addressed: WRS: , Fax (574) 631-6652; JTS , FAX (617)-373-2943
| | | | | | | | - J. Timothy Sage
- To whom correspondence should be addressed: WRS: , Fax (574) 631-6652; JTS , FAX (617)-373-2943
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26
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Silvernail NJ, Barabanschikov A, Sage JT, Noll BC, Scheidt WR. Mapping NO movements in crystalline [Fe(Porph)(NO)(1-MeIm)]. J Am Chem Soc 2009; 131:2131-40. [PMID: 19161328 PMCID: PMC2640452 DOI: 10.1021/ja8055613] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Orientational disorder of the distal nitrosyl (NO) ligand in iron porphyrinates is a common phenomenon. We present an analysis of multitemperature crystallographic data for the order/disorder phenomenon. The observed temperature-dependent order/disorder and variable rotational orientations of nitrosyl ligands for six different six-coordinate iron porphyrinates have been examined in terms of the nonbonded contacts found in the solid state. Favorable orientations for NO can be identified either by calculation of the close nonbonded contacts or by evaluation of the geometry-dependent potential energy using semiempirical nonbonded potential functions. The nonbonded contacts display temperature-dependent differences consistent with observed structural differences. The motion of NO appears to be controlled by intermolecular interactions that allow a limited set of orientations, and under some conditions, only a single NO orientation is allowed. In some cases, the equilibria involving the orientations of NO can be analyzed using the van't Hoff relationship, and the free energy and enthalpy of the solid-state transitions can be evaluated. The intrinsic barriers to rotation of the NO were examined using a fine-meshed series of DFT calculations. The calculations also showed the detailed effects of the variation of the NO orientation on the equatorial bond distances.
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Affiliation(s)
| | | | | | | | - W. Robert Scheidt
- To whom correspondence should be addressed: E-mail , Fax (574) 631-6652
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27
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Silvernail NJ, Olmstead MM, Noll BC, Scheidt WR. Tetragonal to triclinic--a phase change for [Fe(TPP)(NO)]. Inorg Chem 2009; 48:971-7. [PMID: 19128024 PMCID: PMC2680005 DOI: 10.1021/ic801617q] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The temperature dependence of the crystalline phase of (nitrosyl)(tetraphenylporphinato)iron(II), [Fe(TPP)(NO)], has been explored over the temperature range of 33-293 K. The crystalline complex is found in the tetragonal crystal system at higher temperatures and in the triclinic crystal system at lower temperatures. In the tetragonal system, the axial ligand is strongly disordered, with the molecule having crystallographically required 4/m symmetry, leading to eight distinct positions of the single nitrosyl oxygen atom. The phase transition to the triclinic crystal system leads to a partial ordering with the molecule now having inversion symmetry and disorder of the axial nitrosyl ligand over only two positions. The increase in ordering allows subtle molecular geometry features to be observed; in particular, an off-axis tilt of the Fe-N(NO) bond from the heme normal is apparent. The transition of the reversible phase change begins at about 250 K. This transition has been confirmed by both X-ray diffraction studies and a differential scanning calorimetry study.
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Affiliation(s)
- Nathan J. Silvernail
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
| | | | - Bruce C. Noll
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
| | - W. Robert Scheidt
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
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28
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Synthesis, crystal structure and electrochemistry of a ruthenium complex coordinated with an ambidentate 2-mercaptopyridinato N-oxide ligand. Polyhedron 2008. [DOI: 10.1016/j.poly.2008.03.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Chiavarino B, Crestoni ME, Fornarini S, Lanucara F, Lemaire J, Maître P, Scuderi D. Direct Probe of NO Vibration in the Naked Ferric Heme Nitrosyl Complex. Chemphyschem 2008; 9:826-8. [DOI: 10.1002/cphc.200800086] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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30
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Naota T, Tannna A, Kamuro S, Hieda M, Ogata K, Murahashi SI, Takaya H. SwitchableC- andN-Bound Isomers of Transition-Metal Cyanocarbanions: Synthesis and Interconversions of Cyclopentadienyl Ruthenium Complexes of Phenylsulfonylacetonitrile Anions. Chemistry 2008; 14:2482-98. [DOI: 10.1002/chem.200701315] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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31
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Silvernail NJ, Pavlik JW, Noll BC, Schulz CE, Scheidt WR. Reversible NO motion in crystalline [Fe(Porph)(1-MeIm)(NO)] derivatives. Inorg Chem 2008; 47:912-20. [PMID: 18173262 DOI: 10.1021/ic701700p] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The synthesis, characterization, and X-ray structures of three low-spin (nitrosyl)iron(II) tetraarylporphyrinates, [Fe(TpXPP)(NO)(1-MeIm)], where X = F (in a triclinic and a monoclinic form) and OCH(3) are reported. All three molecules, at 100 K, have a single orientation of NO. These structures are the first examples of ordered NO's in [Fe(Porph)(NO)(1-MeIm)] complexes. The three new derivatives have similar structural features including a previously unnoted "bowing" of the N(NO)-Fe-N(Im) angle caused by a concerted tilting of the axial Fe-N(NO) and Fe-N(Im) bonds. Structural features such as the displacement of Fe out of the mean porphyrin plane toward NO, tilting of the Fe-N(NO) bond off the heme normal, and the asymmetry of the Fe-N(por) bonds further strengthen and confirm observations from earlier studies. The [Fe(TpXPP)(NO)(1-MeIm)] complexes were also studied at temperatures between 125 and 350 K to investigate temperature-dependent variations and trends in the coordination group geometry. At varying temperatures (above 150 K), all three derivatives display a second orientation of the NO ligand. The population and depopulation of this second orientation are thermally driven, with no apparent hysteresis. Crystal packing appears to be the significant feature in defining the order/disorder of the NO ligand. The length of the bond trans to NO, Fe-N(Im), was also found to be sensitive to temperature variation. The Fe-N(Im) bond length increases with increased temperature, whereas no other bonds change appreciably. The temperature-dependent Fe-N(Im) bond length change and cell volume changes are consistent with a "soft" Fe-N(Im) bond. Variable-temperature measurements show that the N-O stretching frequency changes with the Fe-N(Im) bond length. Temperature-dependent changes in the Fe-NIm bond length and N-O stretching frequency were also found to be completely reversible with no apparent hysteresis.
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Affiliation(s)
- Nathan J Silvernail
- Contribution from the Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
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32
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Nutt DR, Meuwly M. Ferric and ferrous iron in nitroso-myoglobin: computer simulations of stable and metastable States and their infrared spectra. Chemphyschem 2007; 8:527-36. [PMID: 17330815 DOI: 10.1002/cphc.200600563] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The binding of NO to iron is involved in the biological function of many heme proteins. Contrary to ligands like CO and O(2), which only bind to ferrous (Fe(II)) iron, NO binds to both ferrous and ferric (Fe(III)) iron. In a particular protein, the natural oxidation state can therefore be expected to be tailored to the required function. Herein, we present an ab initio potential-energy surface for ferric iron interacting with NO. This potential-energy surface exhibits three minima corresponding to eta(1)-NO coordination (the global minimum), eta(1)-ON coordination and eta(2) coordination. This contrasts with the potential-energy surface for Fe(II)-NO, which exhibits only two minima (the eta(2) coordination mode for Fe(II) is a transition state, not a minimum). In addition, the binding energies of NO are substantially larger for Fe(III) than for Fe(II). We have performed molecular dynamics simulations for NO bound to ferric myoglobin (Mb(III)) and compare these with results obtained for Mb(II). Over the duration of our simulations (1.5 ns), all three binding modes are found to be stable at 200 K and transiently stable at 300 K, with eventual transformation to the eta(1)-NO global-minimum conformation. We discuss the implication of these results related to studies of rebinding processes in myoglobin.
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Affiliation(s)
- David R Nutt
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
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Nutt DR, Karplus M, Meuwly M. Potential Energy Surface and Molecular Dynamics of MbNO: Existence of an Unsuspected FeON Minimum. J Phys Chem B 2005; 109:21118-25. [PMID: 16853735 DOI: 10.1021/jp0523975] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ligands such as CO, O(2), or NO are involved in the biological function of myoglobin. Here we investigate the energetics and dynamics of NO interacting with the Fe(II) heme group in native myoglobin using ab initio and molecular dynamics simulations. At the global minimum of the ab initio potential energy surface (PES), the binding energy of 23.4 kcal/mol and the Fe-NO structure compare well with the experimental results. Interestingly, the PES is found to exhibit two minima: There exists a metastable, linear Fe-O-N minimum in addition to the known, bent Fe-N-O global minimum conformation. Moreover, the T-shaped configuration is found to be a saddle point, in contrast to the corresponding minimum for NO interacting with Fe(III). To use the ab initio results for finite temperature molecular dynamics simulations, an analytical function was fitted to represent the Fe-NO interaction. The simulations show that the secondary minimum is dynamically stable up to 250 K and has a lifetime of several hundred picoseconds at 300 K. The difference in the topology of the heme-NO PES from that assumed previously (one deep, single Fe-NO minimum) suggests that it is important to use the full PES for a quantitative understanding of this system. Why the metastable state has not been observed in the many spectroscopic studies of myoglobin interacting with NO is discussed, and possible approaches to finding it are outlined.
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Affiliation(s)
- David R Nutt
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
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35
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Praneeth VKK, Neese F, Lehnert N. Spin Density Distribution in Five- and Six-Coordinate Iron(II)−Porphyrin NO Complexes Evidenced by Magnetic Circular Dichroism Spectroscopy. Inorg Chem 2005; 44:2570-2. [PMID: 15819537 DOI: 10.1021/ic050144k] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Using magnetic circular dichroism (MCD) spectroscopy together with DFT calculations, the spin density distributions in five-coordinate [Fe(TPP)(NO)] (I) and six-coordinate [Fe(TPP)(MI)(NO)] (II, MI = 1-methylimidazole) are defined. In the five-coordinate complex, a strong Fe-NO sigma bond between pi(*)(h) and d(z)(2) is present that leads to a large transfer of spin density from the NO ligand to Fe(II) corresponding to an electronic structure with noticeable Fe(I)-NO(+) character. Consequently, the MCD spectrum is dominated by paramagnetic C-term contributions. On coordination of the sixth ligand, the spin density is pushed back from the iron toward the NO ligand, resulting in an Fe(II)-NO(radical) type of electronic structure. This is reflected by the fact that the MCD spectrum is dominated by diamagnetic contributions.
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Affiliation(s)
- V K K Praneeth
- Institut für Anorganische Chemie, Christian-Albrechts-Universität Kiel, Olshausenstrasse 40, 24098 Kiel, Germany
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Ford PC, Fernandez BO, Lim MD. Mechanisms of Reductive Nitrosylation in Iron and Copper Models Relevant to Biological Systems. Chem Rev 2005; 105:2439-55. [PMID: 15941218 DOI: 10.1021/cr0307289] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Peter C Ford
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, 93106-9510, USA.
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37
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Ford PC, Laverman LE. Reaction mechanisms relevant to the formation of iron and ruthenium nitric oxide complexes. Coord Chem Rev 2005. [DOI: 10.1016/j.ccr.2004.04.006] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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38
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Lee J, Kovalevsky AY, Novozhilova IV, Bagley KA, Coppens P, Richter-Addo GB. Single- and double-linkage isomerism in a six-coordinate iron porphyrin containing nitrosyl and nitro ligands. J Am Chem Soc 2004; 126:7180-1. [PMID: 15186147 DOI: 10.1021/ja0488986] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Density Functional theoretical calculations confirm the experimental observation that the low-temperature photolysis of (TPP)Fe(NO)(NO2) (as a KBr pellet) results in the generation of linkage isomers involving the axial NO and NO2 groups and suggest the possible formation of the double linkage isomer (TPP)Fe(ON)(ONO). The energy difference between the ground state (porphine)Fe(NO)(NO2) and the double-linkage isomer (porphine)Fe(ON)(ONO) is 1.57 eV, which is comparable to the 1.59 eV calculated previously for the nitrosyl-to-isonitrosyl linkage isomerism in the five-coordinate (porphine)Fe(NO) analogue.
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Affiliation(s)
- Jonghyuk Lee
- Department of Chemistry and Biochemistry, University of Oklahoma, 620 Parrington Oval, Norman, Oklahoma 73019, USA
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39
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Affiliation(s)
- J A McCleverty
- School of Chemistry, University of Bristol, Bristol BS8 1TS, England
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40
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Bitterwolf TE. Photolysis of [(η5-C5H5)M(CO)2NO]+, where M = Mn and Re, in inert ionic matrices. J Photochem Photobiol A Chem 2004. [DOI: 10.1016/j.jphotochem.2003.11.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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41
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Wyllie GRA, Schulz CE, Scheidt WR. Five- to six-coordination in (nitrosyl)iron(II) porphyrinates: effects of binding the sixth ligand. Inorg Chem 2003; 42:5722-34. [PMID: 12950223 PMCID: PMC2080624 DOI: 10.1021/ic034473t] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report structural and spectroscopic data for a series of six-coordinate (nitrosyl)iron(II) porphyrinates. The structures of three tetraphenylporphyrin complexes [Fe(TPP)(NO)(L)], where L = 4-(dimethylamino)pyridine, 1-methylimidazole, 4-methylpiperidine, are reported here to a high degree of precision and allow observation of several previously unobserved structural features. The tight range of bonding parameters for the [FeNO] moiety for these three complexes suggests a canonical representation for six-coordinate systems (Fe-N(p) = 2.007 A, Fe-N(NO) = 1.753 A, angle FeNO = 138.5 degrees ). Comparison of these data with those obtained previously for five-coordinate systems allows the precise determination of the structural effects of binding a sixth ligand. These include lengthening of the Fe-N(NO) bond and a decrease in the Fe-N-O angle. Several other aspects of the geometry of these systems are also discussed, including the first examples of off-axis tilting of a nitrosyl ligand in a six-coordinate [FeNO](7) heme system. We also report the first examples of Mössbauer studies for these complexes. Measurements have been made in several applied magnetic fields as well as in zero field. The spectra differ from those of their five-coordinate analogues. To obtain reasonable fits to applied magnetic field data, rotation of the electrical field gradient is required, consistent with differing g-tensor orientations in the five- vs six-coordinate species.
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42
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Chacón Villalba ME, Güida JA, Varetti EL, Aymonino PJ. The structure of the FeNO group in two metastable states (MS1 and MS2) of the nitroprusside anion in Na2[Fe(CN)5NO].2H2O. Infrared spectra and quantum chemistry calculations for the normal and the 15NO and N18O isotopic substituted substance. Inorg Chem 2003; 42:2622-7. [PMID: 12691569 DOI: 10.1021/ic026095i] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Low temperature infrared spectra of light induced metastable states MS1 and MS2 of the nitroprusside anion in Na(2)[Fe(CN)(5)NO].2H(2)O, isotopically normal and substituted with (15)NO and N(18)O, are presented and discussed. As a consequence of the relatively high population of the MS2 state achieved by further irradiation with 1064 nm light of samples previously irradiated with 488.0 nm light, new bands were seen for the first time, and others, previously reported, were confirmed. The comparison of the spectral data obtained for the FeNO moiety of the isotopically normal as well as of the (15)NO and N(18)O substituted anion with the results of quantum chemical (DFT) calculations support the assignment of the bands which appear after successive irradiations to MS1, the linear Fe(eta(1)-ON) linkage isomer, and to MS2, the side-bound Fe(eta(2)-NO) isomer.
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Affiliation(s)
- M E Chacón Villalba
- CEQUINOR (Centro de Química Inorgánica) (CONICET-UNLP) and LANAIS EFO (CONICET-UNLP), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115, C.C. 962, 1900 La Plata, R. Argentina
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43
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REACTION MECHANISMS OF NITRIC OXIDE WITH BIOLOGICALLY RELEVANT METAL CENTERS. ADVANCES IN INORGANIC CHEMISTRY 2003. [DOI: 10.1016/s0898-8838(03)54004-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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44
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Güida J, Ramos M, Piro O, Aymonino P. Infrared spectra of K 2 [RuCl 5 NO] in two excited metastable states and the evidence for the NO linkage photoisomerization of metastable state I (MSI) in [RuX 5 NO] 2− (X=Cl, CN). J Mol Struct 2002. [DOI: 10.1016/s0022-2860(01)00897-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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45
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Coppens P, Novozhilova I, Kovalevsky A. Photoinduced linkage isomers of transition-metal nitrosyl compounds and related complexes. Chem Rev 2002; 102:861-84. [PMID: 11942781 DOI: 10.1021/cr000031c] [Citation(s) in RCA: 358] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Philip Coppens
- Department of Chemistry, State University of New York at Buffalo, Buffalo, NY 14260-3000, USA.
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46
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Affiliation(s)
- Jens K S Møller
- Food Chemistry, Department of Dairy and Food Science, Royal Veterinary and Agricultural University, Rolighedsvej 30, DK-1958 Frederiksberg C., Denmark
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47
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Affiliation(s)
- Graeme R A Wyllie
- The Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
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48
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Ford PC, Lorkovic IM. Mechanistic aspects of the reactions of nitric oxide with transition-metal complexes. Chem Rev 2002; 102:993-1018. [PMID: 11942785 DOI: 10.1021/cr0000271] [Citation(s) in RCA: 398] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Peter C Ford
- Department of Chemistry and Biochemistry, University of California-Santa Barbara, Santa Barbara, CA 93106, USA
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49
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Wondimagegn T, Ghosh A. A quantum chemical survey of metalloporphyrin-nitrosyl linkage isomers: insights into the observation of multiple FeNO conformations in a recent crystallographic determination of nitrophorin 4. J Am Chem Soc 2001; 123:5680-3. [PMID: 11403599 DOI: 10.1021/ja004314y] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Using density functional theory-based geometry optimizations, we have searched for eta(1)-NO, eta(1)-ON (isonitrosyl), and eta(2)-NO (side-on bound NO) linkage isomers of a number of metalloporphyrin-NO complexes, M(Por)(NO)(L), where Por = porphinato dianion, M = Mn(II), Fe(II), Fe(III), Ru(II), Ru(III), Co(II), and Rh(II), and L = no ligand, SMe, Ph, and imidazole. The eta(1)-NO isomer had the lowest energy in all cases, and the isonitrosyl isomer was also located as a higher energy potential energy minimum in a number of cases. The eta(2)-NO isomer was only located as a minimum for Mn(II) (L = no ligand), Fe(III) (L = no ligand), and Ru(III) (L = Ph, imidazole, pyrdine), suggesting that an [MNO](6) electron count is important for stabilization of the eta(2) mode of ligation. However, in the presence of axial ligands L, the side-on isomers of [FeNO](6) complexes were not stable and opened up to an unusual geometry where the FeN(O) and NO vectors were tilted in opposite directions relative to the heme normal. Exactly such a geometry, as well as a "normal" upright geometry, has been observed in a recent crystallographic determination of nitrophorin 4 (Nature Struct. Biol. 2000, 7, 551), a salivary protein from the blood-sucking insect Rhodnius prolixus. Together, the calculated and experimental result illustrate the extreme softness of the FeNO potential energy surface toward various forms of tilting and bending deformations.
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Affiliation(s)
- T Wondimagegn
- Department of Chemistry, Faculty of Science, University of Tromsø, N-9037 Tromsø, Norway
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50
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Patchkovskii S, Ziegler T. Structural origin of two paramagnetic species in six-coordinated nitrosoiron(II) porphyrins revealed by density functional theory analysis of the g tensors. Inorg Chem 2000; 39:5354-64. [PMID: 11154592 DOI: 10.1021/ic0005691] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Potential energy and electron paramagnetic resonance (EPR) g tensor surfaces of model five- and six-coordinated porphyrins were examined. For both types of complexes, the NO ligand is preferably coordinated end-on, with a Fe-N-O bond angle of approximately 140 degrees. In the free five-coordinated structure, NO undergoes free rotation around the axial Fe-N(NO) bond. This motion is strongly coupled to the saddle-type distortion of the porphyrin ligand. Coordination by the second axial ligand (imidazole) raises the calculated barrier for NO rotation to about 1 kcal/mol, which is further increased by displacements of imidazole from the ideal axial position. The potential energy surface for the dissociation of the weakly coordinated imidazole ligand is exceptionally flat, with variation of the Fe-N(Im) bond length between 2.1 and 2.5 A changing the energy by less than 1 kcal/mol. Experimental orientations of both axial ligands, as well as the Fe-N(Im) bond length, are therefore likely to be determined by the environment of the complex. In contrast to the total energy, calculated EPR g-tensors are sensitive to the orientation of the NO ligand and to the Fe-N(Im) bond length. Contrary to a common assumption, the g tensor component closest to the free-electron value does not coincide with the direction of the Fe-N(NO) bond. From comparison of the calculated and experimental g-tensor components for a range of structures, the rhombic ("type I") EPR signal is assigned to a static structure with NO oriented toward the meso-C atom of the prophyrin ring, and RFe-N(Im) approximately 2.1 A (calcd g1 = 1.95, g2 = 2.00, g3 = 2.04; exptl g1 = 1.96-1.98, g2 = 2.00, g3 = 2.06-2.08). The axial ("type II") EPR signal cannot correspond to any of the static structures studied presently. It is tentatively assigned to a partially dissociated six-coordinated complex (RFe-N(Im) > 2.5 A), with a freely rotating NO ligand (calcd g parallel = 2.00, g perpendicular = 2.03; exptl g parallel = 1.99-2.00, g perpendicular = 2.02-2.03).
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Affiliation(s)
- S Patchkovskii
- Department of Chemistry, University of Calgary, 2500 University Dr. NW, Calgary, Alberta, T2N 1N4 Canada
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