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Ueda K, Sato W, Yanagisawa S, Kubo M, Hada M, Fujii H. Resonance Raman study of oxoiron(IV) porphyrin π-cation radical complex: Porphyrin ligand effect on ν(Fe=O) frequency. J Inorg Biochem 2024; 255:112544. [PMID: 38574491 DOI: 10.1016/j.jinorgbio.2024.112544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 03/22/2024] [Accepted: 03/23/2024] [Indexed: 04/06/2024]
Abstract
Resonance Raman (rR) spectroscopy has been applied to study the nature of the iron-oxo (Fe=O) moiety of oxoiron(IV) porphyrin π-cation radical complex (CompI). While the axial ligand effect on the nature of the Fe=O moiety has been studied with rR spectroscopy, the porphyrin ligand effect has not been studied well. Here, we investigated the porphyrin ligand effect on the Fe=O moiety with rR spectroscopy. The porphyrin ligand effect was modulated by the electron-withdrawing effect of the porphyrin substituent at the meso-position. This study shows that the frequency of the Fe=O stretching band, ν(Fe=O), hardly change even when the electron-withdrawing effect of the porphyrin substituent changes. This result is further supported by theoretical calculation of CompI. The natural atomic charge analysis reveals that the oxo and axial ligands work to buffer the electron-withdrawing effect of the porphyrin substituent. The electron-withdrawing porphyrin substituent shifts an electron population from the ferryl iron to the porphyrin, but the decreased electron population on the ferryl iron is compensated by the shift of the electron population from the oxo ligand and the axial ligand. The shift of the electron population makes the Fe-axial ligand bond length short, but the Fe=O bond length unchanged, resulting in the invariable ν(Fe=O) frequency.
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Affiliation(s)
- Kaho Ueda
- Department of Chemistry, Biology, and Environmental Science, Graduate School of Humanities and Sciences, Nara Women's University, Nara 630-8506, Japan
| | - Wataru Sato
- Graduate School of Science, University of Hyogo, Ako, Hyogo 678-1297, Japan
| | - Sachiko Yanagisawa
- Graduate School of Science, University of Hyogo, Ako, Hyogo 678-1297, Japan
| | - Minoru Kubo
- Graduate School of Science, University of Hyogo, Ako, Hyogo 678-1297, Japan
| | - Masahiko Hada
- Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, Hachioji 192-0397, Japan
| | - Hiroshi Fujii
- Department of Chemistry, Biology, and Environmental Science, Graduate School of Humanities and Sciences, Nara Women's University, Nara 630-8506, Japan.
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Jing Y, Usai R, Liu Y, Kincaid JR. Revealing substrate-induced structural changes in active site of human CYP51 in the presence of its physiological substrates. J Inorg Biochem 2023; 242:112167. [PMID: 36870163 PMCID: PMC10082466 DOI: 10.1016/j.jinorgbio.2023.112167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 02/01/2023] [Accepted: 02/20/2023] [Indexed: 02/27/2023]
Abstract
The human sterol 14α-demethylases (CYP51, CYP is an abbreviation for cytochrome P450) catalyze three-step oxidative removal of 14α-methyl group of lanosterol by first forming an alcohol, then an aldehyde, and finally conducting a CC bond cleavage reaction. This present study utilizes a combination of Resonance Raman spectroscopy and Nanodisc technology to probe the active site structure of CYP51 in the presence of its hydroxylase and lyase substrates. Ligand-binding induced partial low-to-high-spin conversion is observed by applying electronic absorption spectroscopy and Resonance Raman (RR) spectroscopy. This low degree of spin conversion of CYP51 is contributed by the retention of the water ligand coordinated to the heme iron as well as direct interaction between the hydroxyl group of lyase substrate and the iron center. No significant changes in active site structure are found between detergent-stabilized CYP51 and nanodisc-incorporated CYP51, nevertheless, it is demonstrated that nanodisc-incorporated assemblies provide much more well-defined active site RR spectroscopic responses, which induces a larger conversion from low-to-high-spin state in presence of the substrates. Moreover, a positive polar environment around the exogenous diatomic ligand is detected, providing insight into the mechanism of this essential CC bond cleavage reaction.
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Affiliation(s)
- Yuanqi Jing
- Department of Chemistry, Marquette University, Milwaukee, WI 53233, USA
| | - Remigio Usai
- Department of Chemistry, Marquette University, Milwaukee, WI 53233, USA
| | - Yilin Liu
- Department of Chemistry, Marquette University, Milwaukee, WI 53233, USA.
| | - James R Kincaid
- Department of Chemistry, Marquette University, Milwaukee, WI 53233, USA
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3
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Wu F, Jiang F, Yang J, Dai W, Lan D, Shen J, Fang Z. Investigation of Molecular Mechanism of Cobalt Porphyrin Catalyzed CO 2 Electrochemical Reduction in Ionic Liquid by In-Situ SERS. Molecules 2023; 28:molecules28062747. [PMID: 36985719 PMCID: PMC10059646 DOI: 10.3390/molecules28062747] [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: 02/17/2023] [Revised: 03/12/2023] [Accepted: 03/15/2023] [Indexed: 03/30/2023] Open
Abstract
This study explores the electrochemical reduction in CO2 using room temperature ionic liquids as solvents or electrolytes, which can minimize the environmental impact of CO2 emissions. To design effective CO2 electrochemical systems, it is crucial to identify intermediate surface species and reaction products in situ. The study investigates the electrochemical reduction in CO2 using a cobalt porphyrin molecular immobilized electrode in 1-n-butyl-3-methyl imidazolium tetrafluoroborate (BMI.BF4) room temperature ionic liquids, through in-situ surface-enhanced Raman spectroscopy (SERS) and electrochemical technique. The results show that the highest faradaic efficiency of CO produced from the electrochemical reduction in CO2 can reach 98%. With the potential getting more negative, the faradaic efficiency of CO decreases while H2 is produced as a competitive product. Besides, water protonates porphyrin macrocycle, producing pholorin as the key intermediate for the hydrogen evolution reaction, leading to the out-of-plane mode of the porphyrin molecule. Absorption of CO2 by the ionic liquids leads to the formation of BMI·CO2 adduct in BMI·BF4 solution, causing vibration modes at 1100, 1457, and 1509 cm-1. However, the key intermediate of CO2-· radical is not observed. The υ(CO) stretching mode of absorbed CO is affected by the electrochemical Stark effect, typical of CO chemisorbed on a top site.
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Affiliation(s)
- Feng Wu
- Hunan Provincial Key Laboratory of Environmental Catalysis & Waste Recycling, School of Material and Chemical Engineering, Hunan Institute of Engineering, Xiangtan 411104, China
| | - Fengshuo Jiang
- Hunan Provincial Key Laboratory of Environmental Catalysis & Waste Recycling, School of Material and Chemical Engineering, Hunan Institute of Engineering, Xiangtan 411104, China
| | - Jiahao Yang
- Hunan Provincial Key Laboratory of Environmental Catalysis & Waste Recycling, School of Material and Chemical Engineering, Hunan Institute of Engineering, Xiangtan 411104, China
| | - Weiyan Dai
- Hunan Provincial Key Laboratory of Environmental Catalysis & Waste Recycling, School of Material and Chemical Engineering, Hunan Institute of Engineering, Xiangtan 411104, China
| | - Donghui Lan
- Hunan Provincial Key Laboratory of Environmental Catalysis & Waste Recycling, School of Material and Chemical Engineering, Hunan Institute of Engineering, Xiangtan 411104, China
| | - Jing Shen
- Hunan Provincial Key Laboratory of Environmental Catalysis & Waste Recycling, School of Material and Chemical Engineering, Hunan Institute of Engineering, Xiangtan 411104, China
| | - Zhengjun Fang
- Hunan Provincial Key Laboratory of Environmental Catalysis & Waste Recycling, School of Material and Chemical Engineering, Hunan Institute of Engineering, Xiangtan 411104, China
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Chattopadhyay S, Samanta S, Sarkar A, Bhattacharya A, Patra S, Dey A. Silver nanostructure-modified graphite electrode for in-operando SERRS investigation of iron porphyrins during high-potential electrocatalysis. J Chem Phys 2023; 158:044201. [PMID: 36725507 DOI: 10.1063/5.0136333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
In-operando spectroscopic observation of the intermediates formed during various electrocatalytic oxidation and reduction reactions is crucial to propose the mechanism of the corresponding reaction. Surface-enhanced resonance Raman spectroscopy coupled to rotating disk electrochemistry (SERRS-RDE), developed about a decade ago, proved to be an excellent spectroscopic tool to investigate the mechanism of heterogeneous oxygen reduction reaction (ORR) catalyzed by synthetic iron porphyrin complexes under steady-state conditions in water. The information about the formation of the intermediates accumulated during the course of the reaction at the electrode interface helped to develop better ORR catalysts with second sphere residues in the porphyrin rings. To date, the application of this SERRS-RDE setup is limited to ORR only because the thiol self-assembled monolayer (SAM)-modified Ag electrode, used as the working electrode in these experiments, suffers from stability issues at more cathodic and anodic potential, where H2O oxidation, CO2 reduction, and H+ reduction reactions occur. The current investigation shows the development of a second-generation SERRS-RDE setup consisting of an Ag nanostructure (AgNS)-modified graphite electrode as the working electrode. These electrodes show higher stability (compared to the conventional thiol SAM-modified Ag electrode) upon exposure to very high cathodic and anodic potential with a good signal-to-noise ratio in the Raman spectra. The behavior of this modified electrode toward ORR is found to be the same as the SAM-modified Ag electrode, and the same ORR intermediates are observed during electrochemical ORR. At higher cathodic potential, the signatures of Fe(0) porphyrin, an important intermediate in H+ and CO2 reduction reactions, was observed at the electrode-water interface.
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Affiliation(s)
- Samir Chattopadhyay
- School of Chemical Sciences, Indian Association for the Cultivation of Sciences, 2A & 2B Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Soumya Samanta
- School of Chemical Sciences, Indian Association for the Cultivation of Sciences, 2A & 2B Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Ankita Sarkar
- School of Chemical Sciences, Indian Association for the Cultivation of Sciences, 2A & 2B Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Aishik Bhattacharya
- School of Chemical Sciences, Indian Association for the Cultivation of Sciences, 2A & 2B Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Suman Patra
- School of Chemical Sciences, Indian Association for the Cultivation of Sciences, 2A & 2B Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Abhishek Dey
- School of Chemical Sciences, Indian Association for the Cultivation of Sciences, 2A & 2B Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India
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Gupta R, Li XX, Lee Y, Seo MS, Lee YM, Yanagisawa S, Kubo M, Sarangi R, Cho KB, Fukuzumi S, Nam W. Heme compound II models in chemoselectivity and disproportionation reactions. Chem Sci 2022; 13:5707-5717. [PMID: 35694346 PMCID: PMC9116367 DOI: 10.1039/d2sc01232d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 04/11/2022] [Indexed: 11/23/2022] Open
Abstract
Heme compound II models bearing electron-deficient and -rich porphyrins, [FeIV(O)(TPFPP)(Cl)]− (1a) and [FeIV(O)(TMP)(Cl)]− (2a), respectively, are synthesized, spectroscopically characterized, and investigated in chemoselectivity and disproportionation reactions using cyclohexene as a mechanistic probe. Interestingly, cyclohexene oxidation by 1a occurs at the allylic C–H bonds with a high kinetic isotope effect (KIE) of 41, yielding 2-cyclohexen-1-ol product; this chemoselectivity is the same as that of nonheme iron(iv)-oxo intermediates. In contrast, as observed in heme compound I models, 2a yields cyclohexene oxide product with a KIE of 1, demonstrating a preference for C
Created by potrace 1.16, written by Peter Selinger 2001-2019
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C epoxidation. The latter result is interpreted as 2a disproportionating to form [FeIV(O)(TMP+˙)]+ (2b) and FeIII(OH)(TMP), and 2b becoming the active oxidant to conduct the cyclohexene epoxidation. In contrast to 2a, 1a does not disproportionate under the present reaction conditions. DFT calculations confirm that compound II models prefer C–H bond hydroxylation and that disproportionation of compound II models is controlled thermodynamically by the porphyrin ligands. Other aspects, such as acid and base effects on the disproportionation of compound II models, have been discussed as well. Disproportionation of Cpd II models depends on the electron-richness of the porphyrin ligand; Cpd II with an electron-deficient ligand is difficult to disproportionate, whereas Cpd II with an electron-rich ligand readily disproportionates to form Cpd I as a true oxidant.![]()
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Affiliation(s)
- Ranjana Gupta
- Department of Chemistry and Nano Science, Ewha Womans University Seoul 03760 Korea
| | - Xiao-Xi Li
- Department of Chemistry and Nano Science, Ewha Womans University Seoul 03760 Korea
| | - Youngseob Lee
- Department of Chemistry, Jeonbuk National University Jeonju 54896 Korea
| | - Mi Sook Seo
- Department of Chemistry and Nano Science, Ewha Womans University Seoul 03760 Korea
| | - Yong-Min Lee
- Department of Chemistry and Nano Science, Ewha Womans University Seoul 03760 Korea
| | - Sachiko Yanagisawa
- Graduate School of Life Science, University of Hyogo Hyogo 678-1297 Japan
| | - Minoru Kubo
- Graduate School of Life Science, University of Hyogo Hyogo 678-1297 Japan
| | - Ritimukta Sarangi
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Stanford University California 94023 USA
| | - Kyung-Bin Cho
- Department of Chemistry, Jeonbuk National University Jeonju 54896 Korea
| | - Shunichi Fukuzumi
- Department of Chemistry and Nano Science, Ewha Womans University Seoul 03760 Korea
| | - Wonwoo Nam
- Department of Chemistry and Nano Science, Ewha Womans University Seoul 03760 Korea
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Shelby ML, Wildman A, Hayes D, Mara MW, Lestrange PJ, Cammarata M, Balducci L, Artamonov M, Lemke HT, Zhu D, Seideman T, Hoffman BM, Li X, Chen LX. Interplays of electron and nuclear motions along CO dissociation trajectory in myoglobin revealed by ultrafast X-rays and quantum dynamics calculations. Proc Natl Acad Sci U S A 2021; 118:e2018966118. [PMID: 33782122 PMCID: PMC8040624 DOI: 10.1073/pnas.2018966118] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Ultrafast structural dynamics with different spatial and temporal scales were investigated during photodissociation of carbon monoxide (CO) from iron(II)-heme in bovine myoglobin during the first 3 ps following laser excitation. We used simultaneous X-ray transient absorption (XTA) spectroscopy and X-ray transient solution scattering (XSS) at an X-ray free electron laser source with a time resolution of 80 fs. Kinetic traces at different characteristic X-ray energies were collected to give a global picture of the multistep pathway in the photodissociation of CO from heme. In order to extract the reaction coordinates along different directions of the CO departure, XTA data were collected with parallel and perpendicular relative polarizations of the laser pump and X-ray probe pulse to isolate the contributions of electronic spin state transition, bond breaking, and heme macrocycle nuclear relaxation. The time evolution of the iron K-edge X-ray absorption near edge structure (XANES) features along the two major photochemical reaction coordinates, i.e., the iron(II)-CO bond elongation and the heme macrocycle doming relaxation were modeled by time-dependent density functional theory calculations. Combined results from the experiments and computations reveal insight into interplays between the nuclear and electronic structural dynamics along the CO photodissociation trajectory. Time-resolved small-angle X-ray scattering data during the same process are also simultaneously collected, which show that the local CO dissociation causes a protein quake propagating on different spatial and temporal scales. These studies are important for understanding gas transport and protein deligation processes and shed light on the interplay of active site conformational changes and large-scale protein reorganization.
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Affiliation(s)
- Megan L Shelby
- Department of Chemistry, Northwestern University, Evanston, IL 60208
| | - Andrew Wildman
- Department of Chemistry, University of Washington, Seattle, WA 98195
| | - Dugan Hayes
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL 60437
| | - Michael W Mara
- Department of Chemistry, Northwestern University, Evanston, IL 60208
| | | | - Marco Cammarata
- Institut de Physique de Rennes, Université de Rennes, 35042 Rennes CEDEX, France
| | - Lodovico Balducci
- Institut de Physique de Rennes, Université de Rennes, 35042 Rennes CEDEX, France
| | - Maxim Artamonov
- Department of Chemistry, Northwestern University, Evanston, IL 60208
| | - Henrik T Lemke
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA 94025
| | - Diling Zhu
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA 94025
| | - Tamar Seideman
- Department of Chemistry, Northwestern University, Evanston, IL 60208
| | - Brian M Hoffman
- Department of Chemistry, Northwestern University, Evanston, IL 60208;
| | - Xiaosong Li
- Department of Chemistry, University of Washington, Seattle, WA 98195;
| | - Lin X Chen
- Department of Chemistry, Northwestern University, Evanston, IL 60208;
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL 60437
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7
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Gordon JB, Vilbert AC, DiMucci IM, MacMillan SN, Lancaster KM, Moënne-Loccoz P, Goldberg DP. Activation of Dioxygen by a Mononuclear Nonheme Iron Complex: Sequential Peroxo, Oxo, and Hydroxo Intermediates. J Am Chem Soc 2019; 141:17533-17547. [PMID: 31647656 DOI: 10.1021/jacs.9b05274] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The activation of dioxygen by FeII(Me3TACN)(S2SiMe2) (1) is reported. Reaction of 1 with O2 at -135 °C in 2-MeTHF generates a thiolate-ligated (peroxo)diiron complex FeIII2(O2)(Me3TACN)2(S2SiMe2)2 (2) that was characterized by UV-vis (λmax = 300, 390, 530, 723 nm), Mössbauer (δ = 0.53, |ΔEQ| = 0.76 mm s-1), resonance Raman (RR) (ν(O-O) = 849 cm-1), and X-ray absorption (XAS) spectroscopies. Complex 2 is distinct from the outer-sphere oxidation product 1ox (UV-vis (λmax = 435, 520, 600 nm), Mössbauer (δ = 0.45, |ΔEQ| = 3.6 mm s-1), and EPR (S = 5/2, g = [6.38, 5.53, 1.99])), obtained by one-electron oxidation of 1. Cleavage of the peroxo O-O bond can be initiated either photochemically or thermally to produce a new species assigned as an FeIV(O) complex, FeIV(O)(Me3TACN)(S2SiMe2) (3), which was identified by UV-vis (λmax = 385, 460, 890 nm), Mössbauer (δ = 0.21, |ΔEQ| = 1.57 mm s-1), RR (ν(FeIV═O) = 735 cm-1), and X-ray absorption spectroscopies, as well as reactivity patterns. Reaction of 3 at low temperature with H atom donors gives a new species, FeIII(OH)(Me3TACN)(S2SiMe2) (4). Complex 4 was independently synthesized from 1 by the stoichiometric addition of a one-electron oxidant and a hydroxide source. This work provides a rare example of dioxygen activation at a mononuclear nonheme iron(II) complex that produces both FeIII-O-O-FeIII and FeIV(O) species in the same reaction with O2. It also demonstrates the feasibility of forming Fe/O2 intermediates with strongly donating sulfur ligands while avoiding immediate sulfur oxidation.
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Affiliation(s)
- Jesse B Gordon
- Department of Chemistry , The Johns Hopkins University , 3400 North Charles Street , Baltimore , Maryland 21218 , United States
| | - Avery C Vilbert
- Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853 , United States
| | - Ida M DiMucci
- Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853 , United States
| | - Samantha N MacMillan
- Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853 , United States
| | - Kyle M Lancaster
- Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853 , United States
| | - Pierre Moënne-Loccoz
- Department of Chemical Physiology and Biochemistry , Oregon Health & Science University , Portland , Oregon 97239 , United States
| | - David P Goldberg
- Department of Chemistry , The Johns Hopkins University , 3400 North Charles Street , Baltimore , Maryland 21218 , United States
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9
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Experimental and theoretical studies of the porphyrin ligand effect on the electronic structure and reactivity of oxoiron(iv) porphyrin π-cation-radical complexes. J Biol Inorg Chem 2019; 24:483-494. [PMID: 31115764 DOI: 10.1007/s00775-019-01664-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Accepted: 05/09/2019] [Indexed: 01/15/2023]
Abstract
Oxoiron(IV) porphyrin π-cation-radical complexes (Cpd I) have been studied as models for reactive intermediates called compound I in cytochromes P450, peroxidases, and catalases. It has been well known that the electronic structure and reactivity of Cpd I are modulated by the substituted position and the electron-withdrawing ability of the substituent. However, there still remain two major questions: (1) how many electronegative halogen atoms should be introduced in the meso-phenyl group to switch the porphyrin π-cation-radical state of Cpd I? (2) How does the electron-withdrawing effect of the substituent modulate the reactivity of Cpd I? To answer these two questions, we here performed experimental and theoretical studies on the electron-withdrawing effect of the meso-substituent. We gradually increased the electron-withdrawing effect by increasing the number of fluorine atoms in the meso-phenyl group. Spectroscopic analyses of these Cpd I models reveal that the porphyrin radical state shifts from having a2u radical character to having a1u radical character with an increase in the number of the fluorine atoms in the phenyl group, and the ground state of Cpd I switches from the a2u state to the a1u state when four fluorine atoms are introduced in the meso-phenyl group. The switch of the radical state is predicted well by LC-BLYP, but not by the commonly used B3LYP. The theoretical calculations indicate that the electron-withdrawing substituent makes Cpd I more reactive by stabilizing the ferric porphyrin state (product state) more than the Cpd I state (reactant state), generating a larger free energy change in the oxygenation reaction (ΔG) of Cpd I.
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10
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Bacon BA, Liu Y, Kincaid JR, Boon EM. Spectral Characterization of a Novel NO Sensing Protein in Bacteria: NosP. Biochemistry 2018; 57:6187-6200. [PMID: 30272959 DOI: 10.1021/acs.biochem.8b00451] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A novel family of bacterial hemoproteins named NosP has been discovered recently; its members are proposed to function as nitric oxide (NO) responsive proteins involved in bacterial group behaviors such as quorum sensing and biofilm growth and dispersal. Currently, little is known about molecular activation mechanisms in NosP. Here, functional studies were performed utilizing the distinct spectroscopic characteristics associated with the NosP heme cofactor. NosPs from Pseudomonas aeruginosa ( Pa), Vibrio cholerae ( Vc), and Legionella pneumophila ( Lpg) were studied in their ferrous unligated forms as well as their ferrous CO, ferrous NO, and ferric CN adducts. The resonance Raman (rR) data collected on the ferric forms strongly support the existence of a distorted heme cofactor, which is a common feature in NO sensors. The ferrous spectra exhibit a 213 cm-1 feature, which is assigned to the Fe-Nhis stretching mode. The Fe-C and C-O frequencies in the spectra of ferrous CO NosP complexes are inversely correlated with relatively similar frequencies, consistent with a proximal histidine ligand and a relatively hydrophobic environment. The rR spectra obtained for isotopically labeled ferrous NO adducts provide evidence of formation of a 5-coordinate NO complex, resulting from proximal Fe-Nhis cleavage, which is believed to play a role in biological heme-NO signal transduction. Additionally, we found that of the three NosPs studied, Lpg NosP contains the most electropositive ligand binding pocket, while Pa NosP has the most electronegative ligand binding pocket. This pattern is also observed in the measured heme reduction potentials for these three proteins, which may indicate distinct functions for each.
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Affiliation(s)
- Bezalel A Bacon
- Graduate program in Biochemistry and Structural Biology , Stony Brook University , Stony Brook , New York 11790-3400 , United States
| | - Yilin Liu
- Department of Chemistry , Marquette University , Milwaukee , Wisconsin 53233 , United States
| | - James R Kincaid
- Department of Chemistry , Marquette University , Milwaukee , Wisconsin 53233 , United States
| | - Elizabeth M Boon
- Graduate program in Biochemistry and Structural Biology , Stony Brook University , Stony Brook , New York 11790-3400 , United States.,Department of Chemistry and Institute of Chemical Biology and Drug Discovery , Stony Brook University , Stony Brook , New York 11794-3400 , United States
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11
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Zaitseva SV, Tyulyaeva EY, Simonova OR, Zdanovich SA, Tyurin DV, Koifman OI. Highly reactive μ-carbido diiron tetraphenylporphine oxo-species: chemical generation and the oxidation ability. J COORD CHEM 2018. [DOI: 10.1080/00958972.2018.1506109] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- S. V. Zaitseva
- G. A. Krestov Institute of Solution Chemistry of the Russian Academy of Science, Ivanovo, Russian Federation
| | - E. Yu. Tyulyaeva
- G. A. Krestov Institute of Solution Chemistry of the Russian Academy of Science, Ivanovo, Russian Federation
| | - O. R. Simonova
- G. A. Krestov Institute of Solution Chemistry of the Russian Academy of Science, Ivanovo, Russian Federation
| | - S. A. Zdanovich
- G. A. Krestov Institute of Solution Chemistry of the Russian Academy of Science, Ivanovo, Russian Federation
| | - D. V. Tyurin
- Ivanovo State University of Chemistry and Technology, Ivanovo, Russian Federation
| | - O. I. Koifman
- G. A. Krestov Institute of Solution Chemistry of the Russian Academy of Science, Ivanovo, Russian Federation
- Ivanovo State University of Chemistry and Technology, Ivanovo, Russian Federation
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12
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Mokhtari R, Rezaeifard A, Jafarpour M, Farrokhi A. Visible-light driven catalase-like activity of blackberry-shaped {Mo72Fe30} nanovesicles: combined kinetic and mechanistic studies. Catal Sci Technol 2018. [DOI: 10.1039/c8cy00603b] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Catalase-like activity of blackberry-shaped {Mo72Fe30} nanovesicles was exploited in aqueous solution under visible-light irradiation.
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Affiliation(s)
- Rezvan Mokhtari
- Catalysis Research Laboratory
- Department of Chemistry
- Faculty of Science
- University of Birjand
- Birjand
| | - Abdolreza Rezaeifard
- Catalysis Research Laboratory
- Department of Chemistry
- Faculty of Science
- University of Birjand
- Birjand
| | - Maasoumeh Jafarpour
- Catalysis Research Laboratory
- Department of Chemistry
- Faculty of Science
- University of Birjand
- Birjand
| | - Alireza Farrokhi
- Catalysis Research Laboratory
- Department of Chemistry
- Faculty of Science
- University of Birjand
- Birjand
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13
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Zhu Q, Mak PJ, Tuckey RC, Kincaid JR. Active Site Structures of CYP11A1 in the Presence of Its Physiological Substrates and Alterations upon Binding of Adrenodoxin. Biochemistry 2017; 56:5786-5797. [PMID: 28991453 PMCID: PMC6541926 DOI: 10.1021/acs.biochem.7b00766] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The rate-limiting step in the steroid synthesis pathway is catalyzed by CYP11A1 through three sequential reactions. The first two steps involve hydroxylations at positions 22 and 20, generating 20(R),22(R)-dihydroxycholesterol (20R,22R-DiOHCH), with the third stage leading to a C20-C22 bond cleavage, forming pregnenolone. This work provides detailed information about the active site structure of CYP11A1 in the resting state and substrate-bound ferric forms as well as the CO-ligated adducts. In addition, high-quality resonance Raman spectra are reported for the dioxygen complexes, providing new insight into the status of Fe-O-O fragments encountered during the enzymatic cycle. Results show that the three natural substrates of CYP11A1 have quite different effects on the active site structure, including variations of spin state populations, reorientations of heme peripheral groups, and, most importantly, substrate-mediated distortions of Fe-CO and Fe-O2 fragments, as revealed by telltale shifts of the observed vibrational modes. Specifically, the vibrational mode patterns observed for the Fe-O-O fragments with the first and third substrates are consistent with H-bonding interactions with the terminal oxygen, a structural feature that tends to promote O-O bond cleavage to form the Compound I intermediate. Furthermore, such spectral data are acquired for complexes with the natural redox partner, adrenodoxin (Adx), revealing protein-protein-induced active site structural perturbations. While this work shows that Adx has an only weak effect on ferric and ferrous CO states, it has a relatively stronger impact on the Fe-O-O fragments of the functionally relevant oxy complexes.
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Affiliation(s)
- Qianhong Zhu
- Department of Chemistry, Marquette University , Milwaukee, Wisconsin 53233, United States
| | - Piotr J Mak
- Department of Chemistry, Marquette University , Milwaukee, Wisconsin 53233, United States
| | - Robert C Tuckey
- School of Molecular Sciences, The University of Western Australia , Perth, WA 6009, Australia
| | - James R Kincaid
- Department of Chemistry, Marquette University , Milwaukee, Wisconsin 53233, United States
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14
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Scheidt WR, Cheng B, Venugopal Reddy K, Brancato KE. Alternant Bond Distances in Octaethylporphyrin π-Cation Radicals. J PORPHYR PHTHALOCYA 2017. [DOI: 10.1142/s1088424617500080] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The possible appearance and nature of alternant bond distance patterns in the inner 16-membered ring of several octaethylporphyrin [Formula: see text]-cation radicals has been investigated. This study was made possible by recognizing an unexpected solvent system, namely dichloromethane/chloroform, even though the [Formula: see text]-cation species have extremely limited solubility in chloroform. A total of six [M(OEP[Formula: see text]][Formula: see text] derivatives were studied by single-crystal X-ray structure determinations. Two new zinc derivatives display, quantitatively, the same alternant pattern observed previously. A new nickel complex shows a smaller but now probably significant alternant pattern. However, a copper derivative, independently analyzed twice, shows no evidence for an alternant pattern. The importance of ring–ring interactions on the energy of the top two orbitals is shown by two distinct magnesium derivatives. The derivative with strongly overlapped rings displays an alternant bond distance pattern, whereas the other, with a modestly overlapped ring pair, does not. This suggests the importance of strong ring–ring interactions in leading to a pseudo-Jahn-Teller state; this hypothesis is also supported by other prior results.
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Affiliation(s)
- W. Robert Scheidt
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - Beisong Cheng
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - K. Venugopal Reddy
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | - Kristin E. Brancato
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA
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15
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Ohta T, Liu JG, Nagaraju P, Ogura T, Naruta Y. A cryo-generated ferrous-superoxo porphyrin: EPR, resonance Raman and DFT studies. Chem Commun (Camb) 2016; 51:12407-10. [PMID: 26144219 DOI: 10.1039/c5cc03520a] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The resonance Raman analysis of cryo-generated ferrous-superoxy heme has been performed for the first time, and its structure and the reaction mechanism are rationalized by DFT calculations. The presence of another electronic tautomer of ferrous-superoxy heme is predicted computationally.
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Affiliation(s)
- Takehiro Ohta
- Picobiology Institute, Graduate School of Life Science, University of Hyogo, Hyogo 679-5148, Japan.
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16
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Smith AT, Pazicni S, Marvin KA, Stevens DJ, Paulsen KM, Burstyn JN. Functional divergence of heme-thiolate proteins: a classification based on spectroscopic attributes. Chem Rev 2015; 115:2532-58. [PMID: 25763468 DOI: 10.1021/cr500056m] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Aaron T Smith
- †Department of Molecular Biosciences, Northwestern University, 2205 Tech Drive, Evanston, Illinois 60208, United States
| | - Samuel Pazicni
- ‡Department of Chemistry, University of New Hampshire, 23 Academic Way, Durham, New Hampshire 03824, United States
| | - Katherine A Marvin
- §Department of Chemistry, Hendrix College, 1600 Washington Avenue, Conway, Arkansas 72032, United States
| | - Daniel J Stevens
- ∥Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Katherine M Paulsen
- ∥Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Judith N Burstyn
- ∥Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
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17
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Yuan T, Le Thi Ngoc L, van Nieuwkasteele J, Odijk M, van den Berg A, Permentier H, Bischoff R, Carlen ET. In Situ Surface-Enhanced Raman Spectroelectrochemical Analysis System with a Hemin Modified Nanostructured Gold Surface. Anal Chem 2015; 87:2588-92. [DOI: 10.1021/ac504136j] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Tao Yuan
- Analytical
Biochemistry and Department of Pharmacy, University of Groningen, Deusinglaan 1, 9713 AV, Groningen, The Netherlands
| | - Loan Le Thi Ngoc
- MESA+
Institute for Nanotechnology, University of Twente, Drienerlolaan
5, 7522 NB, Enschede, The Netherlands
| | - Jan van Nieuwkasteele
- MESA+
Institute for Nanotechnology, University of Twente, Drienerlolaan
5, 7522 NB, Enschede, The Netherlands
| | - Mathieu Odijk
- MESA+
Institute for Nanotechnology, University of Twente, Drienerlolaan
5, 7522 NB, Enschede, The Netherlands
| | - Albert van den Berg
- MESA+
Institute for Nanotechnology, University of Twente, Drienerlolaan
5, 7522 NB, Enschede, The Netherlands
| | - Hjalmar Permentier
- Analytical
Biochemistry and Department of Pharmacy, University of Groningen, Deusinglaan 1, 9713 AV, Groningen, The Netherlands
| | - Rainer Bischoff
- Analytical
Biochemistry and Department of Pharmacy, University of Groningen, Deusinglaan 1, 9713 AV, Groningen, The Netherlands
| | - Edwin T. Carlen
- MESA+
Institute for Nanotechnology, University of Twente, Drienerlolaan
5, 7522 NB, Enschede, The Netherlands
- Graduate
School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573, Japan
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18
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Zhao J, Moretto J, Le P, Franzen S. Measurement of Internal Substrate Binding in Dehaloperoxidase–Hemoglobin by Competition with the Heme–Fluoride Binding Equilibrium. J Phys Chem B 2015; 119:2827-38. [DOI: 10.1021/jp512996v] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Jing Zhao
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Justin Moretto
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Peter Le
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Stefan Franzen
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
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19
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Shelby ML, Mara MW, Chen LX. New insight into metalloporphyrin excited state structures and axial ligand binding from X-ray transient absorption spectroscopic studies. Coord Chem Rev 2014. [DOI: 10.1016/j.ccr.2014.05.025] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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20
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Mak PJ, Gregory MC, Sligar SG, Kincaid JR. Resonance Raman spectroscopy reveals that substrate structure selectively impacts the heme-bound diatomic ligands of CYP17. Biochemistry 2014; 53:90-100. [PMID: 24328388 PMCID: PMC3922198 DOI: 10.1021/bi4014424] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An important function of steroidogenic cytochromes P450 is the transformation of cholesterol to produce androgens, estrogens, and the corticosteroids. The activities of cytochrome P450c17 (CYP17) are essential in sex hormone biosynthesis, with severe developmental defects being a consequence of deficiency or mutations. The first reaction catalyzed by this multifunctional P450 is the 17α-hydroxylation of pregnenolone (PREG) to 17α-hydroxypregnenolone (17-OH PREG) and progesterone (PROG) to 17α-hydroxyprogesterone (17-OH PROG). The hydroxylated products then either are used for production of corticoids or undergo a second CYP17 catalyzed transformation, representing the first committed step of androgen formation. While the hydroxylation reactions are catalyzed by the well-known Compound I intermediate, the lyase reaction is believed to involve nucleophilic attack of the earlier peroxo- intermediate on the C20-carbonyl. Herein, resonance Raman (rR) spectroscopy reveals that substrate structure does not impact heme structure for this set of physiologically important substrates. On the other hand, rR spectra obtained here for the ferrous CO adducts with these four substrates show that substrates do interact differently with the Fe-C-O fragment, with large differences between the spectra obtained for the samples containing 17-OH PROG and 17-OH PREG, the latter providing evidence for the presence of two Fe-C-O conformers. Collectively, these results demonstrate that individual substrates can differentially impact the disposition of a heme-bound ligand, including dioxygen, altering the reactivity patterns in such a way as to promote preferred chemical conversions, thereby avoiding the profound functional consequences of unwanted side reactions.
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Affiliation(s)
- Piotr J. Mak
- Department of Chemistry, Marquette University, Milwaukee, WI 53233
| | | | - Stephen G. Sligar
- Department of Biochemistry, University of Illinois, Urbana, IL, 61801
- Department of Chemistry, University of Illinois, Urbana, IL, 61801
- College of Medicine, University of Illinois, Urbana, IL, 61801
| | - James R. Kincaid
- Department of Chemistry, Marquette University, Milwaukee, WI 53233
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21
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Rezaeifard A, Jafarpour M. The catalytic efficiency of Fe-porphyrins supported on multi-walled carbon nanotubes in the heterogeneous oxidation of hydrocarbons and sulfides in water. Catal Sci Technol 2014. [DOI: 10.1039/c3cy00554b] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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22
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Mara MW, Shelby M, Stickrath A, Harpham M, Huang J, Zhang X, Hoffman BM, Chen LX. Electronic and Nuclear Structural Snapshots in Ligand Dissociation and Recombination Processes of Iron Porphyrin in Solution: A Combined Optical/X-ray Approach. J Phys Chem B 2013; 117:14089-98. [DOI: 10.1021/jp407094u] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Michael W. Mara
- Department
of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, U.S.A
| | - Megan Shelby
- Department
of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, U.S.A
| | | | | | | | | | - Brian M. Hoffman
- Department
of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, U.S.A
| | - Lin X. Chen
- Department
of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, U.S.A
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23
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Ohta T, Liu JG, Naruta Y. Resonance Raman characterization of mononuclear heme-peroxo intermediate models. Coord Chem Rev 2013. [DOI: 10.1016/j.ccr.2012.05.009] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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24
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Mak PJ, Yang Y, Im S, Waskell LA, Kincaid JR. Experimental Documentation of the Structural Consequences of Hydrogen-Bonding Interactions to the Proximal Cysteine of a Cytochrome P450. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201205912] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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25
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Mak PJ, Yang Y, Im S, Waskell LA, Kincaid JR. Experimental documentation of the structural consequences of hydrogen-bonding interactions to the proximal cysteine of a cytochrome P450. Angew Chem Int Ed Engl 2012; 51:10403-7. [PMID: 22968976 DOI: 10.1002/anie.201205912] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Indexed: 11/09/2022]
Affiliation(s)
- Piotr J Mak
- Department of Chemistry, Marquette University, Milwaukee, WI 53233, USA
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26
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Pan Z, Newcomb M. Acid-catalyzed disproportionation of oxoiron(IV) porphyrins to give oxoiron(IV) porphyrin radical cations. INORG CHEM COMMUN 2011; 14:968-970. [PMID: 21572532 DOI: 10.1016/j.inoche.2011.03.044] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Disproportionation of oxoiron(IV) porphyrin (Compound II) to oxoiron(IV) porphyrin radical cation (Compound I) was studied in three P450 model systems with different electronic structures. Direct conversion of Compound II to Compound I has been observed for 5,10,15,20-tetrakis(2,6-dichlorophenyl)porphyrin (TDCPP) in acid-catalyzed reactions in a mixed solvent of acetonitrile and water (1:1, v/v) containing excess m-CPBA oxidant, with a second-order rate constant of (1.3 ± 0.2) × 10(2) M(-1) s(-1). The acid-catalyzed disproportionation heavily depends on the electron demand of the substituted aryl groups on the porphyrin macrocycle. The disproportionation equilibrium constants show drastic change for the three porphyrin systems.
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Affiliation(s)
- Zhengzheng Pan
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor Street, Chicago, Illinois 60607
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27
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Rezaeifard A, Jafarpour M, Raissi H, Ghiamati E, Tootoonchi A. Factors affecting the reactivity and selectivity in the oxidation of sulfides with tetra-n-butylammonium peroxomonosulfate catalyzed by Mn(III) porphyrins: Significant nitrogen donor effects. Polyhedron 2011. [DOI: 10.1016/j.poly.2010.11.026] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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28
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Kitagishi H, Tamaki M, Ueda T, Hirota S, Ohta T, Naruta Y, Kano K. Oxoferryl Porphyrin/Hydrogen Peroxide System Whose Behavior is Equivalent to Hydroperoxoferric Porphyrin. J Am Chem Soc 2010; 132:16730-2. [DOI: 10.1021/ja106798a] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hiroaki Kitagishi
- Department of Molecular Chemistry and Biochemistry, Faculty of Science and Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321, Japan, Graduate School of Materials Science, Nara Institute Science and Technology, Ikoma, Nara 630-0192, Japan, and Institute for Materials Chemistry and Engineering, Kyushu University, Higashi-ku, Fukuoka 812-8581, Japan
| | - Mariko Tamaki
- Department of Molecular Chemistry and Biochemistry, Faculty of Science and Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321, Japan, Graduate School of Materials Science, Nara Institute Science and Technology, Ikoma, Nara 630-0192, Japan, and Institute for Materials Chemistry and Engineering, Kyushu University, Higashi-ku, Fukuoka 812-8581, Japan
| | - Takunori Ueda
- Department of Molecular Chemistry and Biochemistry, Faculty of Science and Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321, Japan, Graduate School of Materials Science, Nara Institute Science and Technology, Ikoma, Nara 630-0192, Japan, and Institute for Materials Chemistry and Engineering, Kyushu University, Higashi-ku, Fukuoka 812-8581, Japan
| | - Shun Hirota
- Department of Molecular Chemistry and Biochemistry, Faculty of Science and Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321, Japan, Graduate School of Materials Science, Nara Institute Science and Technology, Ikoma, Nara 630-0192, Japan, and Institute for Materials Chemistry and Engineering, Kyushu University, Higashi-ku, Fukuoka 812-8581, Japan
| | - Takehiro Ohta
- Department of Molecular Chemistry and Biochemistry, Faculty of Science and Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321, Japan, Graduate School of Materials Science, Nara Institute Science and Technology, Ikoma, Nara 630-0192, Japan, and Institute for Materials Chemistry and Engineering, Kyushu University, Higashi-ku, Fukuoka 812-8581, Japan
| | - Yoshinori Naruta
- Department of Molecular Chemistry and Biochemistry, Faculty of Science and Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321, Japan, Graduate School of Materials Science, Nara Institute Science and Technology, Ikoma, Nara 630-0192, Japan, and Institute for Materials Chemistry and Engineering, Kyushu University, Higashi-ku, Fukuoka 812-8581, Japan
| | - Koji Kano
- Department of Molecular Chemistry and Biochemistry, Faculty of Science and Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321, Japan, Graduate School of Materials Science, Nara Institute Science and Technology, Ikoma, Nara 630-0192, Japan, and Institute for Materials Chemistry and Engineering, Kyushu University, Higashi-ku, Fukuoka 812-8581, Japan
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29
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Abu Tarboush N, Jensen LMR, Feng M, Tachikawa H, Wilmot CM, Davidson VL. Functional importance of tyrosine 294 and the catalytic selectivity for the bis-Fe(IV) state of MauG revealed by replacement of this axial heme ligand with histidine . Biochemistry 2010; 49:9783-91. [PMID: 20929212 DOI: 10.1021/bi101254p] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The diheme enzyme MauG catalyzes the posttranslational modification of a precursor protein of methylamine dehydrogenase (preMADH) to complete the biosynthesis of its protein-derived tryptophan tryptophylquinone (TTQ) cofactor. It catalyzes three sequential two-electron oxidation reactions which proceed through a high-valent bis-Fe(IV) redox state. Tyr294, the unusual distal axial ligand of one c-type heme, was mutated to His, and the crystal structure of Y294H MauG in complex with preMADH reveals that this heme now has His-His axial ligation. Y294H MauG is able to interact with preMADH and participate in interprotein electron transfer, but it is unable to catalyze the TTQ biosynthesis reactions that require the bis-Fe(IV) state. This mutation affects not only the redox properties of the six-coordinate heme but also the redox and CO-binding properties of the five-coordinate heme, despite the 21 Å separation of the heme iron centers. This highlights the communication between the hemes which in wild-type MauG behave as a single diheme unit. Spectroscopic data suggest that Y294H MauG can stabilize a high-valent redox state equivalent to Fe(V), but it appears to be an Fe(IV)═O/π radical at the five-coordinate heme rather than the bis-Fe(IV) state. This compound I-like intermediate does not catalyze TTQ biosynthesis, demonstrating that the bis-Fe(IV) state, which is stabilized by Tyr294, is specifically required for this reaction. The TTQ biosynthetic reactions catalyzed by wild-type MauG do not occur via direct contact with the Fe(IV)═O heme but via long-range electron transfer through the six-coordinate heme. Thus, a critical feature of the bis-Fe(IV) species may be that it shortens the electron transfer distance from preMADH to a high-valent heme iron.
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Affiliation(s)
- Nafez Abu Tarboush
- Department of Biochemistry, University of Mississippi Medical Center, Jackson, Mississippi 39216, United States
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30
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Dietzek B, Cialla D, Schmitt M, Popp J. Introduction to the Fundamentals of Raman Spectroscopy. CONFOCAL RAMAN MICROSCOPY 2010. [DOI: 10.1007/978-3-642-12522-5_2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
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31
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Ikemura K, Mukai M, Shimada H, Tsukihara T, Yamaguchi S, Shinzawa-Itoh K, Yoshikawa S, Ogura T. Red-excitation resonance Raman analysis of the nu(Fe=O) mode of ferryl-oxo hemoproteins. J Am Chem Soc 2008; 130:14384-5. [PMID: 18847201 DOI: 10.1021/ja805735g] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The Raman excitation profile of the nuFe O mode of horseradish peroxidase compound II exhibits a maximum at 580 nm. This maximum is located within an absorption band with a shoulder assignable to an oxygen-to-iron charge transfer band on the longer wavelength side of the alpha-band. Resonance Raman bands of the nuFe O mode of various ferryl-oxo type hemoproteins measured at 590 nm excitation indicate that many hemoproteins in the ferryl-oxo state have an oxygen-to-iron charge transfer band in the visible region. Since this red-excited resonance Raman technique causes much less photochemical damage in the proteins relative to blue-excited resonance Raman spectroscopy, it produces a higher signal-to-noise ratio and thus represents a powerful tool for investigations of ferryl-oxo intermediates of hemoproteins.
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Affiliation(s)
- Kenichiro Ikemura
- Department of Life Science, Graduate School of Life Science, University of Hyogo, Hyogo, Japan
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32
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Mak PJ, Kincaid JR. Resonance Raman spectroscopic studies of hydroperoxo derivatives of cobalt-substituted myoglobin. J Inorg Biochem 2008; 102:1952-7. [PMID: 18723225 DOI: 10.1016/j.jinorgbio.2008.07.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2008] [Revised: 07/11/2008] [Accepted: 07/14/2008] [Indexed: 11/15/2022]
Abstract
Recent progress in generating and stabilizing reactive heme protein enzymatic intermediates by cryoradiolytic reduction has prompted application of a range of spectroscopic approaches to effectively interrogate these species. The impressive potential of resonance Raman spectroscopy for characterizing such samples has been recently demonstrated in a number of studies of peroxo- and hydroperoxo-intermediates. While it is anticipated that this approach can be productively applied to the wide range of heme proteins whose reaction cycles naturally involve these peroxo- and hydroperoxo-intermediates, one limitation that sometimes arises is the lack of enhancement of the key intraligand nu(O-O) stretching mode in the native systems. The present work was undertaken to explore the utility of cobalt substitution to enhance both the nu(Co-O) and nu(O-O) modes of the CoOOH fragments of hydroperoxo forms of heme proteins bearing a trans-axial histidine linkage. Thus, having recently completed RR studies of hydroperoxo myoglobin, attention is now turned to its cobalt-substituted analogue. Spectra are acquired for samples prepared with (16)O(2) and (18)O(2) to reveal the nu(M-O) and nu(O-O) modes, the latter indeed being observed only for the cobalt-substituted proteins. In addition, spectra of samples prepared in deuterated solvents were also acquired, providing definitive evidence for the presence of the hydroperoxo-species.
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Affiliation(s)
- Piotr J Mak
- Department of Chemistry, Marquette University, Milwaukee, WI 53233, USA
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33
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Murgida DH, Hildebrandt P. Disentangling interfacial redox processes of proteins by SERR spectroscopy. Chem Soc Rev 2008; 37:937-45. [DOI: 10.1039/b705976k] [Citation(s) in RCA: 117] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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34
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Purpero V, Moran GR. The diverse and pervasive chemistries of the alpha-keto acid dependent enzymes. J Biol Inorg Chem 2007; 12:587-601. [PMID: 17431691 DOI: 10.1007/s00775-007-0231-0] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2006] [Accepted: 03/15/2007] [Indexed: 12/01/2022]
Abstract
The number of identified and confirmed alpha-keto acid dependent oxygenases is increasing rapidly. All of these enzymes have a relatively simple liganding arrangement for a single ferrous ion but collectively conduct a highly diverse set of chemistries. While hydroxylations and a variety of oxidation reactions have been most commonly observed, new reactions involving dealkylations, epimerizations and halogenations have recently been discovered. In this minireview we present what is known of the alpha-keto acid dependent enzymes and offer an argument that the chemistry that is unique to each enzyme occurs only after the production of a pivotal ferryl-oxo intermediate.
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Affiliation(s)
- Vincent Purpero
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, 3210 N. Cramer Street, Milwaukee, WI 53211-3029, USA
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35
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Oxygen Activation Mechanism at the Binuclear Site of Heme-Copper Oxidase Superfamily as Revealed by Time-Resolved Resonance Raman Spectroscopy. ACTA ACUST UNITED AC 2007. [DOI: 10.1002/9780470166468.ch6] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
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36
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Terner J, Palaniappan V, Gold A, Weiss R, Fitzgerald MM, Sullivan AM, Hosten CM. Resonance Raman spectroscopy of oxoiron(IV) porphyrin π-cation radical and oxoiron(IV) hemes in peroxidase intermediates. J Inorg Biochem 2006; 100:480-501. [PMID: 16513173 DOI: 10.1016/j.jinorgbio.2006.01.008] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2005] [Accepted: 01/04/2006] [Indexed: 11/15/2022]
Abstract
The catalytic cycle intermediates of heme peroxidases, known as compounds I and II, have been of long standing interest as models for intermediates of heme proteins, such as the terminal oxidases and cytochrome P450 enzymes, and for non-heme iron enzymes as well. Reports of resonance Raman signals for compound I intermediates of the oxo-iron(IV) porphyrin pi-cation radical type have been sometimes contradictory due to complications arising from photolability, causing compound I signals to appear similar to those of compound II or other forms. However, studies of synthetic systems indicated that protein based compound I intermediates of the oxoiron(IV) porphyrin pi-cation radical type should exhibit vibrational signatures that are different from the non-radical forms. The compound I intermediates of horseradish peroxidase (HRP), and chloroperoxidase (CPO) from Caldariomyces fumago do in fact exhibit unique and characteristic vibrational spectra. The nature of the putative oxoiron(IV) bond in peroxidase intermediates has been under discussion in the recent literature, with suggestions that the Fe(IV)O unit might be better described as Fe(IV)-OH. The generally low Fe(IV)O stretching frequencies observed for proteins have been difficult to mimic in synthetic ferryl porphyrins via electron donation from trans axial ligands alone. Resonance Raman studies of iron-oxygen vibrations within protein species that are sensitive to pH, deuteration, and solvent oxygen exchange, indicate that hydrogen bonding to the oxoiron(IV) group within the protein environment contributes to substantial lowering of Fe(IV)O frequencies relative to those of synthetic model compounds.
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Affiliation(s)
- James Terner
- Department of Chemistry, Virginia Commonwealth University, Richmond, VA 23284-2006, USA.
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37
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Kozlowski PM, Kuta J, Ohta T, Kitagawa T. Resonance Raman enhancement of FeIVO stretch in high-valent iron porphyrins: An insight from TD-DFT calculations. J Inorg Biochem 2006; 100:744-50. [PMID: 16529819 DOI: 10.1016/j.jinorgbio.2006.01.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2005] [Revised: 01/10/2006] [Accepted: 01/10/2006] [Indexed: 11/23/2022]
Abstract
Density functional theory (DFT) has been applied to explain the origin of resonance Raman enhancement associated with the Fe(IV)=O stretch observed in iron(IV)oxo porphyrins. To accomplish this electronic excitations of the Im-(Por)Fe(IV)=O model were computed in the 1.5-4.0 eV spectral range using time-dependent DFT (TD-DFT). All electronic transitions having dominant pi-->pi* character were analyzed and assigned in terms of one-electron excitations. It was found that the most intense Soret band has a multi-component character, but the pi (a(2u))-->pi*(d(xz),d(yz)) and pi (a(1u))-->pi*(d(xz),d(yz)) electronic excitations are primarily responsible for observed resonance enhancement of the Fe(IV)=O stretch.
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Affiliation(s)
- Pawel M Kozlowski
- Department of Chemistry, University of Louisville, 2330 South Brook Street, Louisville, KY 40292, USA.
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38
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Fujii H, Kurahashi T, Tosha T, Yoshimura T, Kitagawa T. 17O NMR study of oxo metalloporphyrin complexes: Correlation with electronic structure of MO moiety. J Inorg Biochem 2006; 100:533-41. [PMID: 16510186 DOI: 10.1016/j.jinorgbio.2006.01.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2005] [Revised: 01/11/2006] [Accepted: 01/11/2006] [Indexed: 10/25/2022]
Abstract
(17)O NMR spectroscopy of oxo ligand of oxo metalloporphyrin can be considered as an excellent means to derive information about structure, electronic state, and reactivity of the metal bound oxo ligand. To show the utility of (17)O NMR spectroscopy of oxo ligand of oxo metalloporphyrin, (17)O NMR spectra of oxo ligands of dioxo ruthenium(VI), oxo chromium(IV), and oxo titanium(IV) porphyrins are measured. For all oxo metalloporphyrins, well-resolved (17)O NMR signals are detected in far high frequency region. The (17)O NMR signal of the metal bound oxo ligand shifts high frequency in order of Ru(VI)<Ti(IV)<Cr(IV), thus the (17)O NMR chemical shift does not directly correlate with the oxo-transfer reactivity, Ti(IV)<Cr(IV)<Ru(VI). On the other hand, the (17)O NMR shift of oxo ligand correlates with the bond strength of metal-oxo bond. This suggests that the (17)O NMR signal of metal bound oxo ligand is a sensitive probe to study the nature of metal-oxo bond in oxo metalloporphyrin. The effect of the electron-withdrawing meso-substituent on the (17)O NMR shift of the oxo ligand is also investigated. With increase in the electron-withdrawing effect of the meso-substituent, the (17)O NMR signal of the oxo ligand of oxo chromium(IV) porphyrin shifts high frequency while that of dioxo ruthenium(VI) porphyrin hardly change resonance position. The changes in metal-oxo bonds induced by the electron-withdrawing meso-substituent are discussed on the basis of the (17)O NMR shifts, the strengths of the metal-oxo bonds, and the oxo-transfer reaction rates.
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Affiliation(s)
- Hiroshi Fujii
- Institute for Molecular Science and Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, Myodaiji, Okazaki 444-8787, Japan.
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Neese F. Theoretical spectroscopy of model-nonheme [Fe(IV)OL5]2+ complexes in their lowest triplet and quintet states using multireference ab initio and density functional theory methods. J Inorg Biochem 2006; 100:716-26. [PMID: 16504299 DOI: 10.1016/j.jinorgbio.2006.01.020] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2005] [Revised: 01/13/2006] [Accepted: 01/16/2006] [Indexed: 10/25/2022]
Abstract
The structure, energies and spectroscopic properties of a simple [FeO(NH(3))(5)](2+) model with ground states (3)A(2g) and (5)A(1g) (in approximate C(4v) symmetry) have been studied in some detail using density functional (DFT) and simplified correlated multireference ab initio methods. The results reveal similarities as well as some pronounced differences in the properties of the molecule in the two alternative spin states.
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Affiliation(s)
- Frank Neese
- Max-Planck Institute for Bioinorganic Chemistry, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany.
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40
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Bollinger JM, Krebs C. Stalking intermediates in oxygen activation by iron enzymes: motivation and method. J Inorg Biochem 2006; 100:586-605. [PMID: 16513177 DOI: 10.1016/j.jinorgbio.2006.01.022] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2006] [Accepted: 01/16/2006] [Indexed: 11/16/2022]
Abstract
The study of high-valent-iron enzyme intermediates began in the mid-1900s with the discovery of compounds I (or ES) and II in the heme peroxidases, progressed to non-heme-diiron enzymes in the 1990s with the detection and characterization of the Fe(III)-Fe(IV) complex, X, and the Fe(IV)-Fe(IV) complex, Q, in O(2) activation by ribonucleotide reductase R2 (RNR-R2) and soluble methane monooxygenase (sMMO), respectively, and was most recently extended to mononuclear non-heme-iron oxygenases with the trapping and spectroscopic characterization of the Fe(IV)-oxo intermediate, J, in the reaction of taurine:alpha-ketoglutarate dioxygenase (TauD). Individually, each of these landmark studies helped reveal the chemical logic of that particular enzyme system. Collectively, they have significantly advanced our understanding of Nature's strategies for oxidative transformation of biomolecules (both natural and "xenobiotic"). With high-valent complexes now having been described in representatives of three major classes of iron enzymes, it is an appropriate time to ask whether and what additional insights might be gleaned from further stalking of related intermediates in other systems. In this review, we advocate that there is still much to be learned from this pursuit and summarize the insight provided by two of the landmark discoveries mentioned above (the latter two) and the subsequent studies that they spurred to support our contention. In addition, we attempt to provide, to the extent that it is possible to do so, a "how-to" guide for detection and characterization of such intermediates, focusing primarily on enzymes in which they form by activation of molecular oxygen. In this latter objective, we have drawn from an earlier review by Johnson (Enzymes, third ed. vol. 20, 1992, pp. 1-61) covering, more generally, dissection of enzyme reaction pathways by transient-state kinetic methods. That work elegantly illustrated that, although it may be impossible to develop a true algorithm for the process, a synthesis of guidelines and general principles can be of considerable value.
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Affiliation(s)
- J Martin Bollinger
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, 306 South Frear Building, University Park, PA 16802, USA.
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Bollinger JM, Price JC, Hoffart LM, Barr EW, Krebs C. Mechanism of Taurine: α‐Ketoglutarate Dioxygenase (TauD) from
Escherichia coli. Eur J Inorg Chem 2005. [DOI: 10.1002/ejic.200500476] [Citation(s) in RCA: 162] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- J. Martin Bollinger
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA, Fax: +1‐814‐863‐7024
- Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA
| | - John C. Price
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA, Fax: +1‐814‐863‐7024
| | - Lee M. Hoffart
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA, Fax: +1‐814‐863‐7024
| | - Eric W. Barr
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA, Fax: +1‐814‐863‐7024
| | - Carsten Krebs
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA, Fax: +1‐814‐863‐7024
- Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA
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42
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Oda K, Ogura T, Appelman EH, Yoshikawa S. The intrinsic stability of the second intermediate following the dioxygen-bound form in the O2 reduction by cytochrome c oxidase. FEBS Lett 2004; 570:161-5. [PMID: 15251458 DOI: 10.1016/j.febslet.2004.06.036] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2004] [Revised: 06/09/2004] [Accepted: 06/12/2004] [Indexed: 11/25/2022]
Abstract
Aeration of a two-electron reduced cytochrome c oxidase provides a species with two Raman bands at 804 and 356 cm(-1), identifying it as the second intermediate following the O2-bound species in the enzymatic O2 reduction process. It degrades directly to the fully oxidized form with a half-life time of 70 min at pH 8.0. The stability suggests an effective insulation for the active site in an extremely high oxidation state (Fe4+ with one oxidative equivalent nearby) against spontaneous electron leaks, which would dissipate proton motive force. The formation and degradation of the second intermediate are pH-dependent.
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Affiliation(s)
- Kenji Oda
- Chemistry Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA
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43
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Ogura T, Kitagawa T. Resonance Raman characterization of the P intermediate in the reaction of bovine cytochrome c oxidase. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2004; 1655:290-7. [PMID: 15100044 DOI: 10.1016/j.bbabio.2003.10.013] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2003] [Revised: 10/31/2003] [Accepted: 10/31/2003] [Indexed: 11/21/2022]
Abstract
Reduced cytochrome c oxidase binds molecular oxygen, yielding an oxygenated intermediate first (Oxy) and then converts it to water via the reaction intermediates of P, F, and O in the order of appearance. We have determined the iron-oxygen stretching frequencies for all the intermediates by using time-resolved resonance Raman spectroscopy. The bound dioxygen in Oxy does not form a bridged structure with Cu(B) and the rate of the reaction from Oxy to P (P(R)) is slower at higher pH in the pH range between 6.8 and 8.0. It was established that the P intermediate has an oxo-heme and definitely not the Fe(a(3))-O-O-Cu(B) peroxy bridged structure. The Fe(a(3))=O stretching (nu(Fe=O)) frequency of the P(R) intermediate, 804/764 cm(-1) for (16)O/(18)O, is distinctly higher than that of F intermediate, 785/750 cm(-1). The rate of reaction from P to F in D(2)O solution is evidently slower than that in H(2)O solution, implicating the coupling of the electron transfer with vector proton transfer in this process. The P intermediate (607-nm form) generated in the reaction of oxidized enzyme with H(2)O(2) gave the nu(Fe=O) band at 803/769 cm(-1) for H(2)(16)O(2)/H(2)(18)O(2) and the simultaneously measured absorption spectrum exhibited the difference peak at 607 nm. Reaction of the mixed valence CO adduct with O(2) provided the P intermediate (P(M)) giving rise to an absorption peak at 607 nm and the nu(Fe=O) bands at 804/768 cm(-1). Thus, three kinds of P intermediates are considered to have the same oxo-heme a(3) structure. The nu(4) and nu(2) modes of heme a(3) of the P intermediate were identified at 1377 and 1591 cm(-1), respectively. The Raman excitation profiles of the nu(Fe=O) bands were different between P and F. These observations may mean the formation of a pi cation radical of porphyrin macrocycle in P.
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Affiliation(s)
- Takashi Ogura
- Department of Life Science, Himeji Institute of Technology, Koto, Kamigori-cho, Ako-gun, Hyogo 678-1297, Japan
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44
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Costas M, Mehn MP, Jensen MP, Que L. Dioxygen Activation at Mononuclear Nonheme Iron Active Sites: Enzymes, Models, and Intermediates. Chem Rev 2004; 104:939-86. [PMID: 14871146 DOI: 10.1021/cr020628n] [Citation(s) in RCA: 2014] [Impact Index Per Article: 100.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Miquel Costas
- Departament de Quimica, Universitat de Girona, 17071, Girona, Spain
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45
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Mak PJ, Podstawka E, Kincaid JR, Proniewicz LM. Effects of systematic peripheral group deuteration on the low-frequency resonance Raman spectra of myoglobin derivatives. Biopolymers 2004; 75:217-28. [PMID: 15378481 DOI: 10.1002/bip.20115] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Resonance Raman spectra are reported for a series of systematically deuterated analogues of myoglobin in its deoxy state as well as for its CO and O(2) adducts. Specifically, the myoglobin samples studied are those that have been reconstituted with deuterated protoheme analogues. These include the methine deuterated, protoheme-d4; analogue bearing C(2)H(3) groups at the 1, 3, 5, and 8 positions, protoheme-d12; the species bearing C(2)H(3) groups at the 1 and 3 positions only, 1,3-protoheme-d6; and the species bearing C(2)H(3) groups at the 5 and 8 positions only, 5,8-protoheme-d6. While the results are generally consistent with previously reported data for synthetic metalloporphyrin models and previous studies of labeled heme proteins, the high-quality low-frequency RR data reported here reveal several important aspects of these low-frequency modes. Of special interest is the fact that, using the two d6-protoheme analogues, it is shown that certain modes are apparently localized on particular pyrrole rings, while others are localized on different rings; i.e., several of these low-frequency modes are localized on one side of the heme.
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Affiliation(s)
- Piotr J Mak
- Chemistry Department, Marquette University, Milwaukee, WI 53233, USA
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46
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Lim MH, Rohde JU, Stubna A, Bukowski MR, Costas M, Ho RYN, Munck E, Nam W, Que L. An FeIV=O complex of a tetradentate tripodal nonheme ligand. Proc Natl Acad Sci U S A 2003; 100:3665-70. [PMID: 12644707 PMCID: PMC152979 DOI: 10.1073/pnas.0636830100] [Citation(s) in RCA: 266] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The reaction of [Fe(II)(tris(2-pyridylmethyl)amine, TPA)(NCCH(3))(2)](2+) with 1 equiv. peracetic acid in CH(3)CN at -40 degrees C results in the nearly quantitative formation of a pale green intermediate with lambda(max) at 724 nm ( epsilon approximately 300 M(-1).cm(-1)) formulated as [Fe(IV)(O)(TPA)](2+) by a combination of spectroscopic techniques. Its electrospray mass spectrum shows a prominent feature at mz 461, corresponding to the [Fe(IV)(O)(TPA)(ClO(4))](+) ion. The Mössbauer spectra recorded in zero field reveal a doublet with DeltaE(Q) = 0.92(2) mms and delta = 0.01(2) mms; analysis of spectra obtained in strong magnetic fields yields parameters characteristic of S = 1 Fe(IV)O complexes. The presence of an Fe(IV)O unit is also indicated in its Fe K-edge x-ray absorption spectrum by an intense 1-s --> 3-d transition and the requirement for an ON scatterer at 1.67 A to fit the extended x-ray absorption fine structure region. The [Fe(IV)(O)(TPA)](2+) intermediate is stable at -40 degrees C for several days but decays quantitatively on warming to [Fe(2)(mu-O)(mu-OAc)(TPA)(2)](3+). Addition of thioanisole or cyclooctene at -40 degrees C results in the formation of thioanisole oxide (100% yield) or cyclooctene oxide (30% yield), respectively; thus [Fe(IV)(O)(TPA)](2+) is an effective oxygen-atom transfer agent. It is proposed that the Fe(IV)O species derives from OO bond heterolysis of an unobserved Fe(II)(TPA)-acyl peroxide complex. The characterization of [Fe(IV)(O)(TPA)](2+) as having a reactive terminal Fe(IV)O unit in a nonheme ligand environment lends credence to the proposed participation of analogous species in the oxygen activation mechanisms of many mononuclear nonheme iron enzymes.
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Affiliation(s)
- Mi Hee Lim
- Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota, 207 Pleasant Street SE, Minneapolis, MN 55455, USA
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47
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Rohde JU, In JH, Lim MH, Brennessel WW, Bukowski MR, Stubna A, Münck E, Nam W, Que L. Crystallographic and spectroscopic characterization of a nonheme Fe(IV)-O complex. Science 2003; 299:1037-9. [PMID: 12586936 DOI: 10.1126/science.299.5609.1037] [Citation(s) in RCA: 721] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Following the heme paradigm, it is often proposed that dioxygen activation by nonheme monoiron enzymes involves an iron(IV)=oxo intermediate that is responsible for the substrate oxidation step. Such a transient species has now been obtained from a synthetic complex with a nonheme macrocyclic ligand and characterized spectroscopically. Its high-resolution crystal structure reveals an iron-oxygen bond length of 1.646(3) angstroms, demonstrating that a terminal iron(IV)=oxo unit can exist in a nonporphyrin ligand environment and lending credence to proposed mechanisms of nonheme iron catalysis.
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Affiliation(s)
- Jan-Uwe Rohde
- Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota, 207 Pleasant Street SE, Minneapolis, MN 55455, USA
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48
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Funabiki T. Functional model oxygenations by nonheme iron complexes. ADVANCES IN CATALYTIC ACTIVATION OF DIOXYGEN BY METAL COMPLEXES 2003. [DOI: 10.1007/0-306-47816-1_4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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49
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Zbylut SD, Kincaid JR. Resonance Raman evidence for protein-induced out-of-plane distortion of the heme prosthetic group of mammalian lactoperoxidase. J Am Chem Soc 2002; 124:6751-8. [PMID: 12047196 DOI: 10.1021/ja012578u] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Resonance Raman spectra have been acquired for resting state mammalian lactoperoxidase, LPO(N), and its six-coordinate, low-spin (6CLS) cyanide complex, LPO(CN), as well as for various heme l containing fragments resulting from partial or complete proteolytic digestion. These proteolytic fragments provide a useful set of reference compounds for analysis of the LPO(N) and LPO(CN) enzymes, using various ligands to generate well-defined five-coordinate and six-coordinate high-spin (5CHS and 6CHS) species. In addition, these model compounds, which contain zero, one, or two covalently attached ester linkages to polypeptide chains, are quite useful for determining the extent to which the presence of the ester linkages at the heme periphery affects the characteristic heme resonance Raman marker bands. The spectral results not only provide strong evidence for the formulation of the resting state enzyme as a 6CHS species, but also confirm the previously documented anomalous intensities of several low-frequency resonance Raman bands, which are most reasonably interpreted to arise from a protein-induced out-of-plane distortion of the heme l macrocycle mediated by the covalent ester linkages to the associated polypeptide residues of the intact protein.
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Affiliation(s)
- Steven D Zbylut
- Chemistry Department, Marquette University, Milwaukee, Wisconsin 53233, USA
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50
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Nakamoto K. Resonance Raman spectra and biological significance of high-valent iron(IV,V) porphyrins. Coord Chem Rev 2002. [DOI: 10.1016/s0010-8545(01)00425-8] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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