1
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Radoń M. Predicting spin states of iron porphyrins with DFT methods including crystal packing effects and thermodynamic corrections. Phys Chem Chem Phys 2024. [PMID: 38899797 DOI: 10.1039/d4cp01327a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
Accurate computational treatment of spin states for transition metal complexes, exemplified by iron porphyrins, lies at the heart of quantum bioinorganic chemistry, but at the same time represents a great challenge for approximate density functional theory (DFT) methods, which are predominantly used. Here, the accuracy of DFT methods for spin-state splittings in iron porphyrin is assessed by probing the ability to correctly predict the ground states for six FeIII or FeII complexes experimentally characterized in solid state. For each case, molecular and periodic DFT calculations are employed to quantify the effect of porphyrin side substituents and the crystal packing effect (CPE) on the spin-state splitting. It is proposed to partition the total CPE into additive components, the direct and structural one, the importance of which is shown to significantly vary from case to case. By knowing the substituent effect, the CPE, and the Gibbs free energy thermodynamic correction from calculations, one can employ the experimental ground-state information in order to derive a quantitative constraint on the electronic energy difference for a simplified (porphin) model of the experimentally characterized metalloporphyrin. The constraints derived in such a way-in the form of single or double inequalities-are used to assess the accuracy of dispersion-corrected DFT methods for 6 spin-state splittings of [FeIII(P)(2-MeIm)2]+, [FeIII(P)(2-MeIm)]+, [FeII(P)(THF)2] and [FeII(P)] models (where P is porphin, 2-MeIm is 2-methylimidazole, THF is tetrahydrofuran). These data constitute the new benchmark set of spin states for crystalline iron porphyrins (SSCIP6). The highest accuracy is obtained in the case of double-hybrid functionals (B2PLYP-D3, DSD-PBEB95-D3), whereas hybrid functionals, especially those with reduced admixture of the exact exchange (B3LYP*-D3, TPSSh-D3), are found to considerably overstabilize the intermediate spin state, leading to incorrect ground-state prediction in FeIII porphyrins. The present approach, which can be generalized to other transition metal complexes, is not only useful in method benchmarking, but also sheds light on the interpretations of experimental data for metalloporphyrins, which are important models to understand the electronic properties of heme proteins.
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Affiliation(s)
- Mariusz Radoń
- Faculty of Chemistry, Jagiellonian University, Kraków, Poland.
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2
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Liu S, Xia S, Yue D, Sun H, Hirao H. The Bonding Nature of Fe–CO Complexes in Heme Proteins. Inorg Chem 2022; 61:17494-17504. [DOI: 10.1021/acs.inorgchem.2c02387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Shuyang Liu
- Warshel Institute for Computational Biology, School of Life and Health Sciences, School of Medicine, The Chinese University of Hong Kong, Shenzhen, Guangdong518172, P. R. China
| | - Songyan Xia
- Warshel Institute for Computational Biology, School of Life and Health Sciences, School of Medicine, The Chinese University of Hong Kong, Shenzhen, Guangdong518172, P. R. China
| | - Dongxiao Yue
- Warshel Institute for Computational Biology, School of Life and Health Sciences, School of Medicine, The Chinese University of Hong Kong, Shenzhen, Guangdong518172, P. R. China
| | - Haoran Sun
- Warshel Institute for Computational Biology, School of Life and Health Sciences, School of Medicine, The Chinese University of Hong Kong, Shenzhen, Guangdong518172, P. R. China
| | - Hajime Hirao
- Warshel Institute for Computational Biology, School of Life and Health Sciences, School of Medicine, The Chinese University of Hong Kong, Shenzhen, Guangdong518172, P. R. China
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3
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Volkov VV, McMaster J, Aizenberg J, Perry CC. Mapping blood biochemistry by Raman spectroscopy at the cellular level. Chem Sci 2021; 13:133-140. [PMID: 35059161 PMCID: PMC8694331 DOI: 10.1039/d1sc05764b] [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: 10/19/2021] [Accepted: 12/01/2021] [Indexed: 11/21/2022] Open
Abstract
We report how Raman difference imaging provides insight on cellular biochemistry in vivo as a function of sub-cellular dimensions and the cellular environment. We show that this approach offers a sensitive diagnostic to address blood biochemistry at the cellular level. We examine Raman microscopic images of the distribution of the different hemoglobins in both healthy (discocyte) and unhealthy (echinocyte) blood cells and interpret these images using pre-calculated, accurate pre-resonant Raman tensors for scattering intensities specific to hemoglobins. These tensors are developed from theoretical calculations of models of the oxy, deoxy and met forms of heme benchmarked against the experimental visible spectra of the corresponding hemoglobins. The calculations also enable assignments of the electronic transitions responsible for the colour of blood: these are mainly ligand to metal charge transfer transitions. We assign the electronic transitions responsible for the colour of blood and present a Raman imaging diagnostic approach for individual blood cells.![]()
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Affiliation(s)
- Victor V Volkov
- Interdisciplinary Biomedical Research Centre, School of Science and Technology, Nottingham Trent University. Clifton Lane Nottingham NG11 8NS UK +44 (0)115 8486695
| | - Jonathan McMaster
- School of Chemistry, Faculty of Science, The University of Nottingham Nottingham NG7 2RD UK
| | - Joanna Aizenberg
- John A. Poulson School of Engineering and Applied Sciences, Harvard University 29 Oxford Street Cambridge MA 02138 USA
| | - Carole C Perry
- Interdisciplinary Biomedical Research Centre, School of Science and Technology, Nottingham Trent University. Clifton Lane Nottingham NG11 8NS UK +44 (0)115 8486695
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4
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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: 90] [Impact Index Per Article: 30.0] [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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5
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Yu J, Lai W. Mechanistic insights into dioxygen activation by a manganese corrole complex: a broken-symmetry DFT study. RSC Adv 2021; 11:24852-24861. [PMID: 35481047 PMCID: PMC9036905 DOI: 10.1039/d1ra02722k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 07/08/2021] [Indexed: 12/14/2022] Open
Abstract
The Mn–oxygen species have been implicated as key intermediates in various Mn-mediated oxidation reactions. However, artificial oxidants were often used for the synthesis of the Mn–oxygen intermediates. Remarkably, the Mn(v)–oxo and Mn(iv)–peroxo species have been observed in the activation of O2 by Mn(iii) corroles in the presence of base (OH−) and hydrogen donors. In this work, density functional theory methods were used to get insight into the mechanism of dioxygen activation and formation of Mn(v)–oxo. The results demonstrated that the dioxygen cannot bind to Mn without the axial OH− ligand. Upon the addition of the axial OH− ligand, the dioxygen can bind to Mn in an end-on fashion to give the Mn(iv)–superoxo species. The hydrogen atom transfer from the hydrogen donor (substrate) to the Mn(iv)–superoxo species is the rate-limiting step, having a high reaction barrier and a large endothermicity. Subsequently, the O–C bond formation is concerted with an electron transfer from the substrate radical to the Mn and a proton transfer from the hydroperoxo moiety to the nearby N atom of the corrole ring, generating an alkylperoxo Mn(iii) complex. The alkylperoxo O–O bond cleavage affords a Mn(v)–oxo complex and a hydroxylated substrate. This novel mechanism for the Mn(v)–oxo formation via an alkylperoxo Mn(iii) intermediate gives insight into the O–O bond activation by manganese complexes. DFT calculations revealed a novel mechanism for the formation of Mn(v)–oxo in the dioxygen activation by a Mn(iii) corrole complex involving a Mn(iii)–alkylperoxo intermediate.![]()
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Affiliation(s)
- Jiangfeng Yu
- Department of Chemistry
- Renmin University of China
- Beijing
- China
| | - Wenzhen Lai
- Department of Chemistry
- Renmin University of China
- Beijing
- China
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6
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Ismail TM, Mohan N, Sajith PK. Theoretical study of hydrogen bonding interactions in substituted nitroxide radicals. NEW J CHEM 2021. [DOI: 10.1039/d0nj05362g] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Interaction energy (Eint) of hydrogen bonded complexes of nitroxide radicals can be assessed in terms of the deepest minimum of molecular electrostatic potential (Vmin).
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Affiliation(s)
| | - Neetha Mohan
- Department of Chemistry
- Christopher Ingold Building
- University College London (UCL)
- London WC1H 0AJ
- UK
| | - P. K. Sajith
- Department of Chemistry
- Farook College
- Kozhikode
- India
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7
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Kalita S, Shaik S, Kisan HK, Dubey KD. A Paradigm Shift in the Catalytic Cycle of P450: The Preparatory Choreography during O 2 Binding and Origins of the Necessity for Two Protonation Pathways. ACS Catal 2020. [DOI: 10.1021/acscatal.0c02775] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Surajit Kalita
- Department of Chemistry and Center for Informatics, Shiv Nadar University, NH91 Tehsil Dadri, Greater Noida, Uttar Pradesh 201314, India
| | - Sason Shaik
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 9190400, Israel
| | - Hemanta K. Kisan
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 9190400, Israel
- Department of Chemistry, Utkal University, Bhubaneswar, Odisha 751004, India
| | - Kshatresh Dutta Dubey
- Department of Chemistry and Center for Informatics, Shiv Nadar University, NH91 Tehsil Dadri, Greater Noida, Uttar Pradesh 201314, India
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8
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Saito K, Watabe Y, Miyazaki T, Takayanagi T, Hasegawa JY. Spin-inversion mechanisms in O 2 binding to a model heme compound: A perspective from nonadiabatic wave packet calculations. J Comput Chem 2020; 41:2527-2537. [PMID: 32841410 DOI: 10.1002/jcc.26409] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 07/18/2020] [Accepted: 08/08/2020] [Indexed: 12/13/2022]
Abstract
Spin-inversion dynamics in O2 binding to a model heme complex, which consisted of Fe(II)-porphyrin and imidazole, were studied using nonadiabatic wave packet dynamics calculations. We considered three active nuclear degrees of freedom in the dynamics, including the motions along the Fe-O distance, Fe-O-O angle, and Fe out-of-plane distance. Spin-free potential energy surfaces for the singlet, triplet, quintet, and septet states were developed using density functional theory calculations, and spin-orbit coupling elements were obtained from CASSCF-level electronic structure calculations. The spin-inversion mainly occurred between the singlet state and one of the triplet states due to large spin-orbit couplings and the contributions of other states were extremely small. The present quantum dynamics calculations suggested that the narrow crossing region model plays a dominant role in the O2 binding dynamics. In addition, the one-dimensional Landau-Zener model underestimated the nonadiabatic transition probability.
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Affiliation(s)
- Kohei Saito
- Department of Chemistry, Saitama University, Saitama City, Saitama, Japan
| | - Yuya Watabe
- Department of Chemistry, Saitama University, Saitama City, Saitama, Japan
| | - Takaaki Miyazaki
- Department of Chemistry, Saitama University, Saitama City, Saitama, Japan
| | | | - Jun-Ya Hasegawa
- Institute for Catalysis, Hokkaido University, Sapporo, Hokkaido, Japan
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9
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Soldatova AV, Spiro TG. Alternative modes of O 2 activation in P450 and NOS enzymes are clarified by DFT modeling and resonance Raman spectroscopy. J Inorg Biochem 2020; 207:111054. [PMID: 32217351 PMCID: PMC7247924 DOI: 10.1016/j.jinorgbio.2020.111054] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 01/24/2020] [Accepted: 03/02/2020] [Indexed: 12/11/2022]
Abstract
The functions of heme proteins are modulated by hydrogen bonds (H-bonds) directed at the heme-bound ligands by protein residues. When the gaseous ligands CO, NO, or O2 are bound, their activity is strongly influenced by H-bonds to their atoms. These H-bonds produce characteristic changes in the vibrational frequencies of the heme adduct, which can be monitored by resonance Raman spectroscopy and interpreted with density functional theory (DFT) computations. When the protein employs a cysteinate proximal ligand, bound O2 becomes particularly reactive, the course of the reaction being controlled by H-bonding and proton delivery. In this work, DFT modeling is used to examine the effects of H-bonding to either the terminal (Ot) or proximate (Op) atom of methylthiolate-Fe(II)porphine-O2, as well as to the thiolate S atom. H-bonds to Op produce a positive linear correlation between ν(Fe - O) and ν(O - O), because they increase the sp2 character of Op, weakening both the Fe - O and O - O bonds. H-bonds to Ot produce a negative correlation, because they increase Fe backbonding, strengthening the Fe - O but weakening the O - O bond. Available experimental data accommodate well to the computed pattern. In particular, this correspondence supports the interpretation of cytochrome P450 data by Kincaid and Sligar [M. Gregory, P.J. Mak, S.G. Sligar, J.R. Kincaid, Angew. Chem. Int. Ed. 125 (2013) 5450-5453], involving steering between hydroxylation and lyase reaction channels by differential H-bonds. Similar channeling between the first and second steps of the nitric oxide synthase reaction is likely.
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Affiliation(s)
- Alexandra V Soldatova
- Department of Chemistry, University of Washington, Box 351700, Seattle, WA 98195, United States
| | - Thomas G Spiro
- Department of Chemistry, University of Washington, Box 351700, Seattle, WA 98195, United States.
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10
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Saito K, Watabe Y, Fujihara T, Takayanagi T, Hasegawa JY. Spin-inversion mechanisms in O 2 binding to a model heme complex revisited by density function theory calculations. J Comput Chem 2020; 41:1130-1138. [PMID: 32020659 DOI: 10.1002/jcc.26159] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 01/12/2020] [Accepted: 01/16/2020] [Indexed: 01/10/2023]
Abstract
Spin-inversion mechanisms in O2 binding to a model heme complex, consisting of Fe(II)-porphyrin and imidazole, were investigated using density-functional theory calculations. First, we applied the recently proposed mixed-spin Hamiltonian method to locate spin-inversion structures between different total spin multiplicities. Nine spin-inversion structures were successfully optimized for the singlet-triplet, singlet-quintet, triplet-quintet, and quintet-septet spin-inversion processes. We found that the singlet-triplet spin-inversion points are located around the potential energy surface region at short Fe-O distances, whereas the singlet-quintet and quintet-septet spin-inversion points are located at longer Fe-O distances. This suggests that both narrow and broad crossing models play roles in O2 binding to the Fe-porphyrin complex. To further understand spin-inversion mechanisms, we performed on-the-fly Born-Oppenheimer molecular dynamics calculations. The reaction coordinates, which are correlated to the spin-inversion dynamics between different spin multiplicities, are also discussed.
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Affiliation(s)
- Kohei Saito
- Department of Chemistry, Saitama University, Shimo-Okubo 255, Sakura-ku, Saitama City, Saitama, 338-8570, Japan
| | - Yuya Watabe
- Department of Chemistry, Saitama University, Shimo-Okubo 255, Sakura-ku, Saitama City, Saitama, 338-8570, Japan
| | - Takashi Fujihara
- Department of Chemistry, Saitama University, Shimo-Okubo 255, Sakura-ku, Saitama City, Saitama, 338-8570, Japan
| | - Toshiyuki Takayanagi
- Department of Chemistry, Saitama University, Shimo-Okubo 255, Sakura-ku, Saitama City, Saitama, 338-8570, Japan
| | - Jun-Ya Hasegawa
- Instituteof Catalysis, Hokkaido University, Kita 21, Nishi 10, Kita-ku, Sapporo, Hokkaido, 001-0021, Japan
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11
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Rice DB, Massie AA, Jackson TA. Experimental and Multireference ab Initio Investigations of Hydrogen-Atom-Transfer Reactivity of a Mononuclear MnIV-oxo Complex. Inorg Chem 2019; 58:13902-13916. [DOI: 10.1021/acs.inorgchem.9b01761] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Derek B. Rice
- Department of Chemistry and Center for Environmentally Beneficial Catalysis, The University of Kansas, 1567 Irving Hill Road, Lawrence, Kansas 66045, United States
| | - Allyssa A. Massie
- Department of Chemistry and Center for Environmentally Beneficial Catalysis, The University of Kansas, 1567 Irving Hill Road, Lawrence, Kansas 66045, United States
| | - Timothy A. Jackson
- Department of Chemistry and Center for Environmentally Beneficial Catalysis, The University of Kansas, 1567 Irving Hill Road, Lawrence, Kansas 66045, United States
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12
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Lischka H, Nachtigallová D, Aquino AJA, Szalay PG, Plasser F, Machado FBC, Barbatti M. Multireference Approaches for Excited States of Molecules. Chem Rev 2018; 118:7293-7361. [DOI: 10.1021/acs.chemrev.8b00244] [Citation(s) in RCA: 197] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Hans Lischka
- School of Pharmaceutical Sciences and Technology, Tianjin University, Tianjin 300072, P.R. China
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, United States
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 17, 1090 Vienna, Austria
| | - Dana Nachtigallová
- Institute of Organic Chemistry and Biochemistry v.v.i., The Czech Academy of Sciences, Flemingovo nám. 2, 16610 Prague 6, Czech Republic
- Regional Centre of Advanced Technologies and Materials, Palacký University, 78371 Olomouc, Czech Republic
| | - Adélia J. A. Aquino
- School of Pharmaceutical Sciences and Technology, Tianjin University, Tianjin 300072, P.R. China
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, United States
- Institute for Soil Research, University of Natural Resources and Life Sciences Vienna, Peter-Jordan-Strasse 82, A-1190 Vienna, Austria
| | - Péter G. Szalay
- ELTE Eötvös Loránd University, Laboratory of Theoretical Chemistry, Pázmány Péter sétány 1/A, 1117 Budapest, Hungary
| | - Felix Plasser
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 17, 1090 Vienna, Austria
- Department of Chemistry, Loughborough University, Leicestershire LE11 3TU, United Kingdom
| | - Francisco B. C. Machado
- Departamento de Química, Instituto Tecnológico de Aeronáutica, São José dos Campos 12228-900, São Paulo, Brazil
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14
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Kepp KP. Heme isomers substantially affect heme's electronic structure and function. Phys Chem Chem Phys 2018; 19:22355-22362. [PMID: 28805222 DOI: 10.1039/c7cp03285d] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Inspection of heme protein structures in the protein data bank reveals four isomers of heme characterized by different relative orientations of the vinyl side chains; remarkably, all these have been reported in multiple protein structures. Density functional theory computations explain this as due to similar energy of the isomers but with a sizable (25 kJ mol-1) barrier to interconversion arising from restricted rotation around the conjugated bonds. The four isomers, EE, EZ, ZE, and ZZ, were then investigated as 4-coordinate hemes, as 5-coordinate deoxyhemes, in 6-coordinate O2-adducts of globins and as compound I intermediates typical of heme peroxidases. Substantial differences were observed in electronic properties relevant to heme function: notably, the spin state energy gap of O2-heme adducts, important for fast reversible binding of O2, depends on the isomer state, and O2-binding enthalpies change by up to 16 kJ mol-1; redox potentials change by up to 0.2 V depending on the isomer, and the doublet-quartet energy splitting of compound I, central to "two-state" reactivity, is affected by up to ∼15 kJ mol-1. These effects are consistently seen with three distinct density functionals, i.e. the effects are not method-dependent. Thus, the nature of the isomer state is an important but overlooked feature of heme chemistry and function, and previous and future studies of hemes may be reconsidered in this new context.
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Affiliation(s)
- Kasper P Kepp
- Technical University of Denmark, DTU Chemistry, Building 206, 2800 Kgs. Lyngby, DK, Denmark.
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15
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Phung QM, Pierloot K. The dioxygen adducts of iron and manganese porphyrins: electronic structure and binding energy. Phys Chem Chem Phys 2018; 20:17009-17019. [DOI: 10.1039/c8cp03078b] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The electronic structures of adducts of O2 and metal porphyrins were thoroughly investigated by highly accurate DMRG-CASPT2.
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16
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Kepp KP. Trends in Strong Chemical Bonding in C 2, CN, CN -, CO, N 2, NO, NO +, and O 2. J Phys Chem A 2017; 121:9092-9098. [PMID: 29112409 DOI: 10.1021/acs.jpca.7b08201] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The strong chemical bonds between C, N, and O play a central role in chemistry, and their formation and cleavage are critical steps in very many catalytic processes. The close-lying molecular orbital energies and large correlation effects pose a challenge to electronic structure calculations and have led to different bonding interpretations, most notably for C2. One way to approach this problem is by strict benchmark comparison of related systems. This work reports reference electronic structures and computed bond dissociation enthalpies D0 for C2, CN, CN-, CO, N2, NO, NO+, O2 and related systems C2+ and C2- at chemical accuracy (∼1 kcal/mol or 4 kJ/mol) using CCSD(T)/aug-cc-pV5Z, with additional benchmarks of HF, MP2, CCSD, explicitly correlated F12 methods, and four density functionals. Very large correlation and basis set effects are responsible for up to 93% of total D0. The order of the molecular orbitals 1πu and 3σg changes, as seen in textbooks, depending on total and effective nuclear charge. Linear trends are observed in 2σu-2σg orbital splitting (R2 = 0.91) and in D0 of C2, C2-, and C2+ (R2 = 0.99). The correlation component of D0 of C2 is by far the largest (∼93%) due to a poor HF description. Importantly, density functional theory fails massively in describing this series consistently in both limits of effective nuclear charge, and Hartree-Fock exchange or meta functionals do not remedy this 100 kJ/mol error, which should thus be addressed in future density functional developments as it affects very many studies involving cleavage or formation of these bonds.
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Affiliation(s)
- Kasper P Kepp
- Technical University of Denmark , DTU Chemistry, Building 206, 2800 Kgs. Lyngby, DK- Denmark
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17
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Alkorta I, Elguero J, Elguero E. Nitroxide stable radicals interacting as Lewis bases in hydrogen bonds: A search in the Cambridge structural data base for intermolecular contacts. J Mol Struct 2017. [DOI: 10.1016/j.molstruc.2017.06.101] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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18
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Harcourt RD. Construction of valence bond structures for {FeNO} 7 nitrosyl heme and non-heme complexes. Nitric Oxide 2017; 69:51-55. [PMID: 28478280 DOI: 10.1016/j.niox.2017.04.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 04/30/2017] [Indexed: 02/05/2023]
Abstract
For {FeNO}7 nitrosyl heme and non-heme complexes, with 17 valence shell electrons, FeIINO, FeIINO* and FeIIINO- valence bond structures of the increased-valence type are generated primarily from Lewis valence bond structures by delocalizing non-bonding electrons into diatomic bonding molecular orbitals. Valence bond formulations for the reactions 2MbNO + 2H+ → 2metMb + N2O + H2O and cis MbNO + NO- + 2H+ → metMb + N2O + H2O are also presented.
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Affiliation(s)
- Richard D Harcourt
- School of Chemistry, The University of Melbourne, Victoria 3010 Australia.
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Schuth N, Mebs S, Huwald D, Wrzolek P, Schwalbe M, Hemschemeier A, Haumann M. Effective intermediate-spin iron in O 2-transporting heme proteins. Proc Natl Acad Sci U S A 2017; 114:8556-8561. [PMID: 28739893 PMCID: PMC5559043 DOI: 10.1073/pnas.1706527114] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Proteins carrying an iron-porphyrin (heme) cofactor are essential for biological O2 management. The nature of Fe-O2 bonding in hemoproteins is debated for decades. We used energy-sampling and rapid-scan X-ray Kβ emission and K-edge absorption spectroscopy as well as quantum chemistry to determine molecular and electronic structures of unligated (deoxy), CO-inhibited (carboxy), and O2-bound (oxy) hemes in myoglobin (MB) and hemoglobin (HB) solutions and in porphyrin compounds at 20-260 K. Similar metrical and spectral features revealed analogous heme sites in MB and HB and the absence of low-spin (LS) to high-spin (HS) conversion. Amplitudes of Kβ main-line emission spectra were directly related to the formal unpaired Fe(d) spin count, indicating HS Fe(II) in deoxy and LS Fe(II) in carboxy. For oxy, two unpaired Fe(d) spins and, thus by definition, an intermediate-spin iron center, were revealed by our static and kinetic X-ray data, as supported by (time-dependent) density functional theory and complete-active-space self-consistent-field calculations. The emerging Fe-O2 bonding situation includes in essence a ferrous iron center, minor superoxide character of the noninnocent ligand, significant double-bond properties of the interaction, and three-center electron delocalization as in ozone. It resolves the apparently contradictory classical models of Pauling, Weiss, and McClure/Goddard into a unifying view of O2 bonding, tuned toward reversible oxygen transport.
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Affiliation(s)
- Nils Schuth
- Department of Physics, Freie Universität Berlin, 14195 Berlin, Germany
| | - Stefan Mebs
- Department of Physics, Freie Universität Berlin, 14195 Berlin, Germany
| | - Dennis Huwald
- Department of Plant Biochemistry, Section of Photobiotechnology, Ruhr-Universität Bochum, 44801 Bochum, Germany
| | - Pierre Wrzolek
- Department of Chemistry, Humboldt-Universität zu Berlin, 12489 Berlin, Germany
| | - Matthias Schwalbe
- Department of Chemistry, Humboldt-Universität zu Berlin, 12489 Berlin, Germany
| | - Anja Hemschemeier
- Department of Plant Biochemistry, Section of Photobiotechnology, Ruhr-Universität Bochum, 44801 Bochum, Germany
| | - Michael Haumann
- Department of Physics, Freie Universität Berlin, 14195 Berlin, Germany;
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20
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21
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Shibata T, Kanai Y, Nishimura R, Xu L, Moritaka Y, Suzuki A, Neya S, Nakamura M, Yamamoto Y. Characterization of Ground State Electron Configurations of High-Spin Quintet Ferrous Heme Iron in Deoxy Myoglobin Reconstituted with Trifluoromethyl Group-Substituted Heme Cofactors. Inorg Chem 2016; 55:12128-12136. [DOI: 10.1021/acs.inorgchem.6b01360] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tomokazu Shibata
- Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan
| | - Yuki Kanai
- Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan
| | - Ryu Nishimura
- Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan
| | - Liyang Xu
- Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan
| | - Yuki Moritaka
- Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan
| | - Akihiro Suzuki
- Department of Materials Engineering, Nagaoka National College of Technology, Nagaoka 940-8532, Japan
| | - Saburo Neya
- Department of Physical Chemistry, Graduate School of
Pharmaceutical Sciences, Chiba University, Chuoh-Inohana, Chiba 260-8675, Japan
| | - Mikio Nakamura
- Department
of Chemistry, Faculty of Science, Toho University, Funabashi, Chiba 274-8510, Japan
| | - Yasuhiko Yamamoto
- Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan
- Life Science
Center of Tsukuba Advanced Research Alliance, University of Tsukuba, Tsukuba 305-8577, Japan
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22
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Ashley DC, Baik MH. The Electronic Structure of [Mn(V)═O]: What is the Connection between Oxyl Radical Character, Physical Oxidation State, and Reactivity? ACS Catal 2016. [DOI: 10.1021/acscatal.6b01793] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Daniel Charles Ashley
- Department
of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Mu-Hyun Baik
- Center
for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, South Korea
- Department
of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, South Korea
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23
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Attia AAA, Silaghi-Dumitrescu R. A mononuclear non-heme-iron dioxygen-carrying protein? J Mol Graph Model 2016; 69:103-10. [PMID: 27607306 DOI: 10.1016/j.jmgm.2016.09.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2016] [Revised: 08/31/2016] [Accepted: 09/01/2016] [Indexed: 10/21/2022]
Abstract
The ability of mononuclear non-heme iron complexes to function as molecular oxygen transporters is investigated by density functional theory. The factors governing the efficiency of the reversible binding of dioxygen at the active site of the dinuclear non-heme iron enzyme hemerythrin, including antiferromagnetic coupling and the conversion of dioxygen to hydroperoxo by a proton coupled 2-electron transfer mechanism, are revisited and considered as possible tools in mononuclear non-heme complexes. Several mononuclear non-heme model complexes, including active sites of enzymes already known to interact with dioxgenic ligands, are constructed and the molecular oxygen transportation capabilities of these complexes are examined computationally. The high-spin nature of the ground state of these complexes implies an intrinsic kinetic lability of the oxy structures, as also evident from potential energy surface calculations towards iron-dioxygen cleavage. Proton affinities as calibrated with reference compounds showed that these complexes are highly unlikely to undergo protonation to form hydroperoxo-like adducts. Mixed superoxo descriptions of the dissociated dioxygenic ligands in all complexes add to the overall conclusion that these model structures are significantly disadvantaged in any attempt to be employed for molecular oxygen transportation.
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Affiliation(s)
- Amr A A Attia
- Department of Chemistry, Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, Cluj-Napoca, Romania.
| | - Radu Silaghi-Dumitrescu
- Department of Chemistry, Faculty of Chemistry and Chemical Engineering, Babeş-Bolyai University, Cluj-Napoca, Romania.
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24
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Zhao H, Fang C, Gao J, Liu C. Spin-state energies of heme-related models from spin-flip TDDFT calculations. Phys Chem Chem Phys 2016; 18:29486-29494. [DOI: 10.1039/c6cp04826a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The spin-state energies of heme-related models were calculated by using the spin-flip TDDFT method avoiding spin contamination.
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Affiliation(s)
- Hui Zhao
- Institute of Theoretical Chemistry
- School of Chemistry & Chemical Engineering
- Shandong University
- Jinan
- People's Republic of China
| | - Changfeng Fang
- Department of Physics
- Jining University
- Qufu
- People's Republic of China
| | - Jun Gao
- Institute of Theoretical Chemistry
- School of Chemistry & Chemical Engineering
- Shandong University
- Jinan
- People's Republic of China
| | - Chengbu Liu
- Institute of Theoretical Chemistry
- School of Chemistry & Chemical Engineering
- Shandong University
- Jinan
- People's Republic of China
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25
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Kitagawa Y, Chen Y, Nakatani N, Nakayama A, Hasegawa J. A DFT and multi-configurational perturbation theory study on O2 binding to a model heme compound via the spin-change barrier. Phys Chem Chem Phys 2016; 18:18137-44. [DOI: 10.1039/c6cp02329k] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Potential energy surface of the O2 binding to a model heme compound via minimum energy intersystem crossing point (MEISCP) was investigated with DFT and MS-CASPT2. The porphyrin's symmetric shrinking vibration mode contributes to reach the MESICP from the T1 minimum.
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Affiliation(s)
- Y. Kitagawa
- Institute for Catalysis
- Hokkaido University
- Hokkaido 001-0021
- Japan
| | - Y. Chen
- Institute for Catalysis
- Hokkaido University
- Hokkaido 001-0021
- Japan
| | - N. Nakatani
- Institute for Catalysis
- Hokkaido University
- Hokkaido 001-0021
- Japan
| | - A. Nakayama
- Institute for Catalysis
- Hokkaido University
- Hokkaido 001-0021
- Japan
| | - J. Hasegawa
- Institute for Catalysis
- Hokkaido University
- Hokkaido 001-0021
- Japan
- JST-CREST
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26
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Saito T, Kawakami T, Yamanaka S, Okumura M. Computational Study of Catalytic Reaction of Quercetin 2,4-Dioxygenase. J Phys Chem B 2015; 119:6952-62. [PMID: 25990020 DOI: 10.1021/acs.jpcb.5b03564] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present a quantum mechanics/molecular mechanics (QM/MM) and QM-only study on the oxidative ring-cleaving reaction of quercetin catalyzed by quercetin 2,4-dioxygenase (2,4-QD). 2,4-QD has a mononuclear type 2 copper center and incorporates two oxygen atoms at C2 and C4 positions of the substrate. It has not been clear whether dioxygen reacts with a copper ion or a substrate radical as the first step. We have found that dioxygen is more likely to bind to a Cu(2+) ion, involving the dissociation of the substrate from the copper ion. Then a Cu(2+)-alkylperoxo complex can be generated. Comparison of geometry and stability between QM-only and QM/MM results strongly indicates that steric effects of the protein environment contribute to maintain the orientation of the substrate dissociated from the copper center. The present QM/MM results also highlight that a prior rearrangement of the Cu(2+)-alkylperoxo complex and a subsequent hydrogen bond switching assisted by the movement of Glu73 can facilitate formation of an endoperoxide intermediate selectively.
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Affiliation(s)
- Toru Saito
- †Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan.,‡Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology (JST) Agency, Kawaguchi, Saitama 332-0012, Japan
| | - Takashi Kawakami
- †Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
| | - Shusuke Yamanaka
- †Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan.,‡Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology (JST) Agency, Kawaguchi, Saitama 332-0012, Japan
| | - Mitsutaka Okumura
- †Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan.,‡Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology (JST) Agency, Kawaguchi, Saitama 332-0012, Japan
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27
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Radoń M. Role of Spin States in Nitric Oxide Binding to Cobalt(II) and Manganese(II) Porphyrins. Is Tighter Binding Always Stronger? Inorg Chem 2015; 54:5634-45. [PMID: 26000802 DOI: 10.1021/ic503109a] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Binding of nitric oxide (NO) to metalloporphyrins and heme groups is important in biochemistry while challenging to describe accurately by density functional theory (DFT) calculations. Here, the structural and thermochemical aspect of NO binding to Co(II) and Mn(II) porphyrins is investigated by DFT and DFT-D (dispersion-corrected) calculations, supported by reliable coupled-cluster methodology (CCSD(T)), and critically correlated with the experimental data. It is argued that whereas the bonding of NO to Co(II) porphyrin is a simple radical recombination, the bonding of NO to Mn(II) porphyrin is accompanied by a crossing of spin states. For this reason, the spin-state conversion energy contributes to the Mn-NO bond energy, and the paradigmatic correlation between bond length and bond energy is violated for the considered nitrosyl complexes: the Mn-NO bond is (structurally) shorter by ∼0.2 Å, albeit (energetically) weaker by a few kcal/mol, compared with the Co-NO bond. Moreover, none of the many tested DFT methods can reproduce the Co-NO and Mn-NO bond energies simultaneously, except for calculations with B3LYP*-D3, TPSSh-D3, and M06-D3 methods supplemented with the proposed spin-state energy correction (to compensate for an error on the calculated spin-state conversion energy). The results of this study are important to appreciate the role of spin-state changes in ligand binding properties of heme-related models. They also highlight the need for accurate calculations for correct interpretation of experimental data, including the qualitative structure-energy relationship.
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Affiliation(s)
- Mariusz Radoń
- Faculty of Chemistry, Jagiellonian University, Kraków, Poland
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28
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Crestoni ME, Chiavarino B, Fornarini S. Nitrosyl–heme and anion–arene complexes: structure, reactivity and spectroscopy. PURE APPL CHEM 2015. [DOI: 10.1515/pac-2014-1203] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
AbstractTwo topics are selected and illustrated to exemplify (i) a biological and (ii) an organic ionic intermediate. The reactivity behavior of NO adducts with ferric and ferrous hemes has shown remarkable similarities when examined in the gas phase, demonstrating that the largely different NO affinity displayed in solution and in biological media is due to the different coordination environment. In fact, ferrous hemes present a vacant or highly labile axial coordination site, prone to readily bind NO. The vibrational signatures of the NO ligand have also been probed in vacuo for the first time in the nitrosyl complexes deriving from ferrous and ferric hemes under strictly comparable five-coordination at the metal center. Negatively charged σ-adducts, from the association of anions with 1,3,5-trinitrobenzene, an exemplary π-electron-deficient arene, have been probed by IRMPD spectroscopy and found to display variable binding motifs from a strongly covalent σ-adduct (Meisenheimer complex) to a weakly covalent σ-complex, depending on the anion basicity.
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Affiliation(s)
- Maria Elisa Crestoni
- 1Dipartimento di Chimica e Tecnologie del Farmaco, Università degli Studi di Roma La Sapienza, P.le A. Moro 5, I-00185, Roma, Italy
| | - Barbara Chiavarino
- 1Dipartimento di Chimica e Tecnologie del Farmaco, Università degli Studi di Roma La Sapienza, P.le A. Moro 5, I-00185, Roma, Italy
| | - Simonetta Fornarini
- 1Dipartimento di Chimica e Tecnologie del Farmaco, Università degli Studi di Roma La Sapienza, P.le A. Moro 5, I-00185, Roma, Italy
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29
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Quantum chemical DFT study of the interaction between molecular oxygen and FeN4 complexes, and effect of the macrocyclic ligand. J Mol Model 2014; 20:2131. [DOI: 10.1007/s00894-014-2131-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2013] [Accepted: 12/27/2013] [Indexed: 10/25/2022]
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30
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Broclawik E, Stępniewski A, Radoń M. Nitric oxide as a non-innocent ligand in (bio-)inorganic complexes: spin and electron transfer in Fe(II)-NO bond. J Inorg Biochem 2014; 136:147-53. [PMID: 24495545 DOI: 10.1016/j.jinorgbio.2014.01.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 01/10/2014] [Accepted: 01/10/2014] [Indexed: 11/27/2022]
Abstract
The nature of electron density transfer upon bond formation between NO ligand and Fe(II) center is analyzed on the basis of DFT calculation for two {Fe-NO}(7) complexes with entirely diverse geometric and electronic structures: Fe(II)P(NH3)NO (with bent Fe-N-O unit) and [Fe(II)(H2O)5(NO)](2+) (with linear Fe-N-O structure). Proper identification of an electronic status of the fragments, "prepared" to make a bond, was found necessary to get meaningful resolution of charge and spin transfer processes from a spin-resolved analysis of natural orbitals for chemical valence. The Fe(II)P(NH3)NO adduct (built of NO(0) (S=1/2) and Fe(II)P(NH3) (S=0) fragments) showed a strong π*-backdonation competing with spin transfer via a σ-donation, yielding significant red-shift of the NO stretching frequency. [Fe(II)(H2O)5(NO)](2+) (built of NO(0) (S=1/2) antiferromagnetically coupled to Fe(II)(H2O)5 (S=2) fragment) gave no noticeable charge or spin transfer between fragments; a slight blue-shift of the NO stretching frequency could be related to a residual π-donation due to weak π-bonding.
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Affiliation(s)
- Ewa Broclawik
- Jerzy Haber Institute of Catalysis PAS, ul. Niezapominajek 8, 30-239 Krakow, Poland.
| | - Adam Stępniewski
- Jerzy Haber Institute of Catalysis PAS, ul. Niezapominajek 8, 30-239 Krakow, Poland
| | - Mariusz Radoń
- Faculty of Chemistry, Jagiellonian University, ul. Ingardena 3, 30-060 Krakow, Poland
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31
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Kurashige Y, Saitow M, Chalupský J, Yanai T. Radical O–O coupling reaction in diferrate-mediated water oxidation studied using multireference wave function theory. Phys Chem Chem Phys 2014; 16:11988-99. [DOI: 10.1039/c3cp55225j] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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32
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Radoń M. Revisiting the role of exact exchange in DFT spin-state energetics of transition metal complexes. Phys Chem Chem Phys 2014; 16:14479-88. [DOI: 10.1039/c3cp55506b] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Sensitivity of DFT spin-state energetics to exact exchange is rooted in the description of metal–ligand bonding.
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Affiliation(s)
- Mariusz Radoń
- Faculty of Chemistry
- Jagiellonian University in Kraków
- 30-060 Kraków, Poland
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33
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Harcourt RD. The McClure and Weiss models of Fe–O2 bonding for oxyhemes, and the HbO2 + NO reaction. J Biol Inorg Chem 2013; 19:113-23. [DOI: 10.1007/s00775-013-1066-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Accepted: 11/06/2013] [Indexed: 10/25/2022]
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34
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X-ray absorption spectroscopic investigation of the electronic structure differences in solution and crystalline oxyhemoglobin. Proc Natl Acad Sci U S A 2013; 110:16333-8. [PMID: 24062465 DOI: 10.1073/pnas.1315734110] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Hemoglobin (Hb) is the heme-containing O2 transport protein essential for life in all vertebrates. The resting high-spin (S = 2) ferrous form, deoxy-Hb, combines with triplet O2, forming diamagnetic (S = 0) oxy-Hb. Understanding this electronic structure is the key first step in understanding transition metal-O2 interaction. However, despite intense spectroscopic and theoretical studies, the electronic structure description of oxy-Hb remains elusive, with at least three different descriptions proposed by Pauling, Weiss, and McClure-Goddard, based on theory, spectroscopy, and crystallography. Here, a combination of X-ray absorption spectroscopy and extended X-ray absorption fine structure, supported by density functional theory calculations, help resolve this debate. X-ray absorption spectroscopy data on solution and crystalline oxy-Hb indicate both geometric and electronic structure differences suggesting that two of the previous descriptions are correct for the Fe-O2 center in oxy-Hb. These results support the multiconfigurational nature of the ground state developed by theoretical results. Additionally, it is shown here that small differences in hydrogen bonding and solvation effects can tune the ground state, tipping it into one of the two probable configurations. These data underscore the importance of solution spectroscopy and show that the electronic structure in the crystalline form may not always reflect the true ground-state description in solution.
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35
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Vysotskiy VP, Boström J, Veryazov V. A new module for constrained multi-fragment geometry optimization in internal coordinates implemented in the MOLCAS package. J Comput Chem 2013; 34:2657-65. [DOI: 10.1002/jcc.23428] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Revised: 08/01/2013] [Accepted: 08/05/2013] [Indexed: 11/11/2022]
Affiliation(s)
- Victor P. Vysotskiy
- Department of Theoretical Chemistry; Chemical Center, Lund University; P.O. Box 124 S-221 00 Lund Sweden
| | - Jonas Boström
- Department of Theoretical Chemistry; Chemical Center, Lund University; P.O. Box 124 S-221 00 Lund Sweden
| | - Valera Veryazov
- Department of Theoretical Chemistry; Chemical Center, Lund University; P.O. Box 124 S-221 00 Lund Sweden
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36
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Soldatova AV, Ibrahim M, Spiro TG. Electronic structure and ligand vibrations in FeNO, CoNO, and FeOO porphyrin adducts. Inorg Chem 2013; 52:7478-86. [PMID: 23763617 PMCID: PMC3766410 DOI: 10.1021/ic400364x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The gaseous ligands, CO, NO, and O2 interact with the Fe ion in heme proteins largely via backbonding of Fe electrons to the π* orbitals of the XO (X = C, N, O) ligands. In these FeXO adducts, the Fe-X stretching frequency varies inversely with the X-O stretching frequency, since increased backbonding strengthens the Fe-X bond while weakening the X-O bond. Inverse frequency correlations have been observed for all three ligands, despite differing electronic and geometric structures, and despite variable composition of the "FeX" vibrational mode, in which Fe-X stretching and Fe-X-O coordinates are mixed for bent FeXO adducts. We report experimental data for 5-coordinate Co(II)(NO) porphyrin adducts (isoelectronic with Fe(II)(OO) adducts), and the results of density functional theory (DFT) modeling for 5-coordinate Fe(II)(NO), Co(II)(NO), and Fe(II)(OO) adducts. Inverse ν(MX)/ν(XO) correlations are obtained computationally, using model porphyrins with graded electron-donating and -withdrawing substituents to modulate the backbonding. Computed slopes agree satisfactorily with experiment, provided nonhybrid functionals are used, which avoid overemphasizing high-spin states. The BP86 functional gives correct ground states, a closed-shell singlet for Co(II)(NO) and an open-shell singlet for the isoelectronic Fe(II)(OO), as corroborated by structural data for Co(II)(NO), and the ν(MX)/ν(XO) slope agreement with experiment for both adducts. However, for Fe(II)(OO) adducts, the computed inverse ν(MX)/ν(XO) correlation applies only to porphyrins with electron-donating and withdrawing substituents of moderate strength. For substituents more donating than -CH3, a direct correlation is obtained, the Fe-O and O-O bonds weakening in concert. This effect is ascribed to the dominance of σ bonding via the in-plane dxz(+dz(2))-π* orbital, when electron-donating substituents raise the d orbital energies sufficiently to render backbonding (dyz-π*) unimportant.
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Affiliation(s)
- Alexandra V. Soldatova
- Department of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195
| | | | - Thomas G. Spiro
- Department of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195
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37
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Shi Q, Chen H. Theoretical methods for excited state dynamics of molecules and molecular aggregates. Sci China Chem 2013. [DOI: 10.1007/s11426-013-4914-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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38
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Charkin OP. Theoretical study of the structure and stability of oxo heme derivatives. RUSS J INORG CHEM+ 2013. [DOI: 10.1134/s0036023613030042] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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39
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Attia AAA, Lupan A, Silaghi-Dumitrescu R. Spin state preference and bond formation/cleavage barriers in ferrous-dioxygen heme adducts: remarkable dependence on methodology. RSC Adv 2013. [DOI: 10.1039/c3ra45789c] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
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40
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Spiro TG, Soldatova AV. Ambidentate H-bonding of NO and O2 in heme proteins. J Inorg Biochem 2012; 115:204-10. [PMID: 22824153 DOI: 10.1016/j.jinorgbio.2012.05.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2012] [Revised: 05/08/2012] [Accepted: 05/10/2012] [Indexed: 01/26/2023]
Abstract
The affinity and reactivity of the gaseous molecules CO, NO and O(2) (XO) in heme protein adducts are controlled by secondary interactions, especially by H-bonds donated from distal protein residues. Vibrational spectroscopy, supported by DFT (Density Functional Theory) modeling, has revealed that for NO and O(2), but not for CO, a critical issue is whether the H-bond is donated to the outer or inner atom of the bound diatomic ligand. DFT modeling shows that bound NO and O(2) are ambidentate, both atoms separately acting as H-bond acceptors. This is not the case for CO, whose π* orbital acts as a delocalized H-bond acceptor. Vibrational spectra of heme-XO adducts reveal a general pattern of backbonding variations, marked by families of negative correlations between frequencies associated with FeX and XO bond stretches. For heme-CO adducts, H-bonding increases backbonding, the νFeX/νXO points moving up the backbonding correlation established with model compounds. For NO and O(2) adducts, however, increased backbonding is only observed when the outer atom is the H-bond acceptor. H-bonding to the inner (X) atom instead produces a positive νFeX/νXO correlation. This effect can be reproduced by DFT modeling. Its mechanism is polarization of the sp(2) orbital on the X atom, on the back side of the bent FeXO unit, drawing electrons from both the FeX and XO bonds and weakening them together. Thus, the positioning of H-bond donors in the protein differentially affects bonding and reactivity in heme adducts of NO and O(2).
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Affiliation(s)
- Thomas G Spiro
- Department of Chemistry, University of Washington, Box 351700, Seattle, WA 98195, USA.
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Oxygen activation in neuronal NO synthase: resolving the consecutive mono-oxygenation steps. Biochem J 2012; 443:505-14. [PMID: 22300432 DOI: 10.1042/bj20111644] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The vital signalling molecule NO is produced by mammalian NOS (nitric oxide synthase) enzymes in two steps. L-arginine is converted into NOHA (Nω-hydroxy-L-arginine), which is converted into NO and citrulline. Both steps are thought to proceed via similar mechanisms in which the cofactor BH4 (tetrahydrobiopterin) activates dioxygen at the haem site by electron transfer. The subsequent events are poorly understood due to the lack of stable intermediates. By analogy with cytochrome P450, a haem-iron oxo species may be formed, or direct reaction between a haem-peroxy intermediate and substrate may occur. The two steps may also occur via different mechanisms. In the present paper we analyse the two reaction steps using the G586S mutant of nNOS (neuronal NOS), which introduces an additional hydrogen bond in the active site and provides an additional proton source. In the mutant enzyme, BH4 activates dioxygen as in the wild-type enzyme, but an interesting intermediate haem species is then observed. This may be a stabilized form of the active oxygenating species. The mutant is able to perform step 2 (reaction with NOHA), but not step 1 (with L-arginine) indicating that the extra hydrogen bond enables it to discriminate between the two mono-oxygenation steps. This implies that the two steps follow different chemical mechanisms.
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Rokob TA, Srnec M, Rulíšek L. Theoretical calculations of physico-chemical and spectroscopic properties of bioinorganic systems: current limits and perspectives. Dalton Trans 2012; 41:5754-68. [DOI: 10.1039/c2dt12423h] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Ghosh A. Ab initio wavefunctions in bioinorganic chemistry: More than a succès d'estime? J Biol Inorg Chem 2011; 16:819-20. [PMID: 21755384 PMCID: PMC3139065 DOI: 10.1007/s00775-011-0816-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 06/30/2011] [Indexed: 12/02/2022]
Affiliation(s)
- Abhik Ghosh
- Department of Chemistry and Center for Theoretical and Computational Chemistry, University of Tromsø, Norway.
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