1
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Ali HS, Henchman RH, de Visser SP. Lignin Biodegradation by a Cytochrome P450 Enzyme: A Computational Study into Syringol Activation by GcoA. Chemistry 2020; 26:13093-13102. [PMID: 32613677 PMCID: PMC7590115 DOI: 10.1002/chem.202002203] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Indexed: 12/12/2022]
Abstract
A recently characterized cytochrome P450 isozyme GcoA activates lignin components through a selective O-demethylation or alternatively an acetal formation reaction. These are important reactions in biotechnology and, because lignin is readily available; it being the main component in plant cell walls. In this work we present a density functional theory study on a large active site model of GcoA to investigate syringol activation by an iron(IV)-oxo heme cation radical oxidant (Compound I) leading to hemiacetal and acetal products. Several substrate-binding positions were tested and full energy landscapes calculated. The study shows that substrate positioning determines the product distributions. Thus, with the phenol group pointing away from the heme, an O-demethylation is predicted, whereas an initial hydrogen-atom abstraction of the weak phenolic O-H group would trigger a pathway leading to ring-closure to form acetal products. Predictions on how to engineer P450 GcoA to get more selective product distributions are given.
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Affiliation(s)
- Hafiz Saqib Ali
- Manchester Institute of BiotechnologyThe University of Manchester131 Princess StreetManchesterM1 7DNUnited Kingdom
- Department of ChemistryThe University of ManchesterOxford RoadManchesterM13 9PLUnited Kingdom
| | - Richard H. Henchman
- Manchester Institute of BiotechnologyThe University of Manchester131 Princess StreetManchesterM1 7DNUnited Kingdom
- Department of ChemistryThe University of ManchesterOxford RoadManchesterM13 9PLUnited Kingdom
| | - Sam P. de Visser
- Manchester Institute of BiotechnologyThe University of Manchester131 Princess StreetManchesterM1 7DNUnited Kingdom
- Department of Chemical Engineering and Analytical ScienceThe University of ManchesterOxford RoadManchesterM13 9PLUnited Kingdom
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2
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Cha L, Milikisiyants S, Davidson M, Xue S, Smirnova T, Smirnov A, Guo Y, Chang WC. Alternative Reactivity of Leucine 5-Hydroxylase Using an Olefin-Containing Substrate to Construct a Substituted Piperidine Ring. Biochemistry 2020; 59:1961-1965. [PMID: 32401494 DOI: 10.1021/acs.biochem.0c00289] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Applying enzymatic reactions to produce useful molecules is a central focus of chemical biology. Iron and 2-oxoglutarate (Fe/2OG) enzymes are found in all kingdoms of life and catalyze a broad array of oxidative transformations. Herein, we demonstrate that the activity of an Fe/2OG enzyme can be redirected when changing the targeted carbon hybridization from sp3 to sp2. During leucine 5-hydroxylase catalysis, installation of an olefin group onto the substrate redirects the Fe(IV)-oxo species reactivity from hydroxylation to asymmetric epoxidation. The resulting epoxide subsequently undergoes intramolecular cyclization to form the substituted piperidine, 2S,5S-hydroxypipecolic acid.
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Affiliation(s)
- Lide Cha
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Sergey Milikisiyants
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Madison Davidson
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Shan Xue
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Tatyana Smirnova
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Alex Smirnov
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Yisong Guo
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Wei-Chen Chang
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
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3
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Visser SP. Second‐Coordination Sphere Effects on Selectivity and Specificity of Heme and Nonheme Iron Enzymes. Chemistry 2020; 26:5308-5327. [DOI: 10.1002/chem.201905119] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 12/04/2019] [Indexed: 12/11/2022]
Affiliation(s)
- Sam P. Visser
- The Manchester Institute of Biotechnology and Department of Chemical Engineering and Analytical ScienceThe University of Manchester 131 Princess Street Manchester M1 7DN UK
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4
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Zhang Y. Computational Investigations of Heme Carbenes and Heme Carbene Transfer Reactions. Chemistry 2019; 25:13231-13247. [DOI: 10.1002/chem.201901984] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 06/19/2019] [Indexed: 12/15/2022]
Affiliation(s)
- Yong Zhang
- Department of Chemistry and Chemical Biology Stevens Institute of Technology 1 Castle Point on Hudson Hoboken NJ 07030 USA
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5
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Wang H, Schulz CE, Wei X, Li J. New Insights into the Ligand Nature of Carbene: Synthesis and Characterizations of Six-Coordinate Iron(II) Carbene Porphyrin Complexes. Inorg Chem 2018; 58:143-151. [PMID: 30565937 DOI: 10.1021/acs.inorgchem.8b02043] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Charles E. Schulz
- Department of Physics, Knox College, Galesburg, Illinois 61401, United States
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6
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Cantú Reinhard FG, DuBois JL, de Visser SP. Catalytic Mechanism of Nogalamycin Monoxygenase: How Does Nature Synthesize Antibiotics without a Metal Cofactor? J Phys Chem B 2018; 122:10841-10854. [DOI: 10.1021/acs.jpcb.8b09648] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Fabián G. Cantú Reinhard
- Manchester Institute of Biotechnology and School of Chemical Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
| | - Jennifer L. DuBois
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59715-3400, United States
| | - Sam P. de Visser
- Manchester Institute of Biotechnology and School of Chemical Engineering and Analytical Science, The University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
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7
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Chatfield DC, Morozov AN. Proximal Pocket Controls Alkene Oxidation Selectivity of Cytochrome P450 and Chloroperoxidase toward Small, Nonpolar Substrates. J Phys Chem B 2018; 122:7828-7838. [PMID: 30052045 DOI: 10.1021/acs.jpcb.8b04279] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
This paper examines the influence of the proximal pockets of cytochrome P450CAM and chloroperoxidase (CPO) on the relative favorability of catalytic epoxidation and allylic hydroxylation of olefins, a type of alkene oxidation selectivity. The study employs quantum mechanical models of the active site to isolate the proximal pocket's influence on the barrier for the selectivity-determining step for each reaction, using cyclohexene and cis-β-methylstyrene as substrates. The proximal pocket is found to preference epoxidation by 2-5 kcal/mol, the largest value being for CPO, converting the active heme-thiolate moiety from being intrinsically hydroxylation-selective to being intrinsically epoxidation-selective. This theoretical study, the first to correctly predict these enzymes' preference for epoxidation of allylic substrates, strongly suggests that the proximal pocket is the key determinant of alkene oxidation selectivity. The selectivity for epoxidation can be rationalized in terms of the proximal pocket's modulation of the thiolate's electron "push" and consequent influence on the heme redox potential and the basicity of the trans ligand.
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Affiliation(s)
- David C Chatfield
- Department of Chemistry and Biochemistry , Florida International University , 11200 8th Street , Miami , Florida 33199 , United States
| | - Alexander N Morozov
- Department of Chemistry and Biochemistry , Florida International University , 11200 8th Street , Miami , Florida 33199 , United States
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8
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Liu Y, Xu W, Zhang J, Fuller W, Schulz CE, Li J. Electronic Configuration and Ligand Nature of Five-Coordinate Iron Porphyrin Carbene Complexes: An Experimental Study. J Am Chem Soc 2017; 139:5023-5026. [PMID: 28339195 DOI: 10.1021/jacs.7b01722] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The five-coordinate iron porphyrin carbene complexes [Fe(TPP) (CCl2)] (TPP = tetraphenylporphyrin), [Fe(TTP) (CCl2)] (TTP = tetratolylporphyrin) and [Fe(TFPP) (CPh2)] (TFPP = tetra(pentafluorophenyl)porphyrin), utilizing two types of carbene ligands (CCl2 and CPh2), have been investigated by single crystal X-ray, XANES (X-ray absorption near edge spectroscopy), Mössbauer, NMR and UV-vis spectroscopies. The XANES suggested the iron(II) oxidation state of the complexes. The multitemperature and high magnetic field Mössbauer experiments, which show very large quadrupole splittings (QS, ΔEQ), determined the S = 0 electronic configuration. More importantly, combined structural and Mössbauer studies, especially the comparison with the low spin iron(II) porphyrin complexes with strong diatomic ligands (CS, CO and CN-) revealed the covalent bond nature of the carbene ligands. A correlation between the iron isomer shifts (IS, δ) and the axial bond distances is established for the first time for these donor carbon ligands (:C-R).
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Affiliation(s)
- Yulong Liu
- College of Materials Science and Optoelectronic Technology, University of Chinese Academy of Sciences , Yanqi Lake, Huairou District, Beijing 101408, China
| | - Wei Xu
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences , Beijing 100049, China
| | - Jing Zhang
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences , Beijing 100049, China
| | - William Fuller
- Department of Physics, Knox College , Galesburg, Illinois 61401, United States
| | - Charles E Schulz
- Department of Physics, Knox College , Galesburg, Illinois 61401, United States
| | - Jianfeng Li
- College of Materials Science and Optoelectronic Technology, University of Chinese Academy of Sciences , Yanqi Lake, Huairou District, Beijing 101408, China
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9
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Renata H, Lewis RD, Sweredoski MJ, Moradian A, Hess S, Wang ZJ, Arnold FH. Identification of Mechanism-Based Inactivation in P450-Catalyzed Cyclopropanation Facilitates Engineering of Improved Enzymes. J Am Chem Soc 2016; 138:12527-33. [PMID: 27573353 DOI: 10.1021/jacs.6b06823] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Following the recent discovery that heme proteins can catalyze the cyclopropanation of styrenyl olefins with high efficiency and selectivity, interest in developing new enzymes for a variety of non-natural carbene transfer reactions has burgeoned. The fact that diazo compounds and other carbene precursors are known mechanism-based inhibitors of P450s, however, led us to investigate if they also interfere with this new enzyme function. We present evidence for two inactivation pathways that are operative during cytochrome P450-catalyzed cyclopropanation. Using a combination of UV-vis, mass spectrometry, and proteomic analyses, we show that the heme cofactor and several nucleophilic side chains undergo covalent modification by ethyl diazoacetate (EDA). Substitution of two of the affected residues with less-nucleophilic amino acids led to a more than twofold improvement in cyclopropanation performance (total TTN). Elucidating the inactivation pathways of heme protein-based carbene transfer catalysts should aid in the optimization of this new biocatalytic function.
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Affiliation(s)
- Hans Renata
- Division of Chemistry and Chemical Engineering, MC 210-41, and ‡Proteome Exploration Laboratory, Division of Biology and Biological Engineering, Beckman Institute, MC 139-74, California Institute of Technology , 1200 E California Blvd, Pasadena, California 91125, United States
| | - Russell D Lewis
- Division of Chemistry and Chemical Engineering, MC 210-41, and ‡Proteome Exploration Laboratory, Division of Biology and Biological Engineering, Beckman Institute, MC 139-74, California Institute of Technology , 1200 E California Blvd, Pasadena, California 91125, United States
| | - Michael J Sweredoski
- Division of Chemistry and Chemical Engineering, MC 210-41, and ‡Proteome Exploration Laboratory, Division of Biology and Biological Engineering, Beckman Institute, MC 139-74, California Institute of Technology , 1200 E California Blvd, Pasadena, California 91125, United States
| | - Annie Moradian
- Division of Chemistry and Chemical Engineering, MC 210-41, and ‡Proteome Exploration Laboratory, Division of Biology and Biological Engineering, Beckman Institute, MC 139-74, California Institute of Technology , 1200 E California Blvd, Pasadena, California 91125, United States
| | - Sonja Hess
- Division of Chemistry and Chemical Engineering, MC 210-41, and ‡Proteome Exploration Laboratory, Division of Biology and Biological Engineering, Beckman Institute, MC 139-74, California Institute of Technology , 1200 E California Blvd, Pasadena, California 91125, United States
| | - Z Jane Wang
- Division of Chemistry and Chemical Engineering, MC 210-41, and ‡Proteome Exploration Laboratory, Division of Biology and Biological Engineering, Beckman Institute, MC 139-74, California Institute of Technology , 1200 E California Blvd, Pasadena, California 91125, United States
| | - Frances H Arnold
- Division of Chemistry and Chemical Engineering, MC 210-41, and ‡Proteome Exploration Laboratory, Division of Biology and Biological Engineering, Beckman Institute, MC 139-74, California Institute of Technology , 1200 E California Blvd, Pasadena, California 91125, United States
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10
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de Visser SP, Stillman MJ. Challenging Density Functional Theory Calculations with Hemes and Porphyrins. Int J Mol Sci 2016; 17:519. [PMID: 27070578 PMCID: PMC4848975 DOI: 10.3390/ijms17040519] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 03/22/2016] [Accepted: 03/23/2016] [Indexed: 01/09/2023] Open
Abstract
In this paper we review recent advances in computational chemistry and specifically focus on the chemical description of heme proteins and synthetic porphyrins that act as both mimics of natural processes and technological uses. These are challenging biochemical systems involved in electron transfer as well as biocatalysis processes. In recent years computational tools have improved considerably and now can reproduce experimental spectroscopic and reactivity studies within a reasonable error margin (several kcal·mol(-1)). This paper gives recent examples from our groups, where we investigated heme and synthetic metal-porphyrin systems. The four case studies highlight how computational modelling can correctly reproduce experimental product distributions, predicted reactivity trends and guide interpretation of electronic structures of complex systems. The case studies focus on the calculations of a variety of spectroscopic features of porphyrins and show how computational modelling gives important insight that explains the experimental spectra and can lead to the design of porphyrins with tuned properties.
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Affiliation(s)
- Sam P de Visser
- Manchester Institute of Biotechnology and School of Chemical Engineering and Analytical Science, the University of Manchester, 131 Princess Street, Manchester M1 7DN, UK.
| | - Martin J Stillman
- Department of Chemistry, The University of Western Ontario, London, ON N6A 5B7, Canada.
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11
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Biocatalysts for the formation of three- to six-membered carbo- and heterocycles. Biotechnol Adv 2015; 33:457-80. [DOI: 10.1016/j.biotechadv.2015.01.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Accepted: 01/27/2015] [Indexed: 11/18/2022]
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12
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Khade RL, Zhang Y. Catalytic and Biocatalytic Iron Porphyrin Carbene Formation: Effects of Binding Mode, Carbene Substituent, Porphyrin Substituent, and Protein Axial Ligand. J Am Chem Soc 2015; 137:7560-3. [PMID: 26067900 PMCID: PMC4482416 DOI: 10.1021/jacs.5b03437] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Indexed: 11/28/2022]
Abstract
Iron porphyrin carbenes (IPCs) are important intermediates in various chemical reactions catalyzed by iron porphyrins and engineered heme proteins, as well as in the metabolism of various xenobiotics by cytochrome P450. However, there are no prior theoretical reports to help understand their formation mechanisms and identify key information governing the binding mode, formation feasibility, and stability/reactivity. A systematic quantum chemical study was performed to investigate the effects of carbene substituent, porphyrin substituent, and axial ligand on IPC formation pathways. Results not only are consistent with available experimental data but also provide a number of unprecedented insights into electronic, steric, and H-bonding effects of various structural factors on IPC formation mechanisms. These results shall facilitate research on IPC and related systems for sustainable chemical catalysis and biocatalysis.
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Affiliation(s)
- Rahul L Khade
- Department of Chemistry, Chemical Biology, and Biomedical Engineering, Stevens Institute of Technology, Castle Point on Hudson, Hoboken, New Jersey 07030, United States
| | - Yong Zhang
- Department of Chemistry, Chemical Biology, and Biomedical Engineering, Stevens Institute of Technology, Castle Point on Hudson, Hoboken, New Jersey 07030, United States
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13
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Sainna MA, Kumar S, Kumar D, Fornarini S, Crestoni ME, de Visser SP. A comprehensive test set of epoxidation rate constants for iron(iv)-oxo porphyrin cation radical complexes. Chem Sci 2014; 6:1516-1529. [PMID: 29560240 PMCID: PMC5811088 DOI: 10.1039/c4sc02717e] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 12/08/2014] [Indexed: 12/31/2022] Open
Abstract
Trends in oxygen atom transfer to Compound I of the P450 models with an extensive test set have been studied and show a preferred regioselectivity of epoxidation over hydroxylation in the gas-phase for the first time.
Cytochrome P450 enzymes are heme based monoxygenases that catalyse a range of oxygen atom transfer reactions with various substrates, including aliphatic and aromatic hydroxylation as well as epoxidation reactions. The active species is short-lived and difficult to trap and characterize experimentally, moreover, it reacts in a regioselective manner with substrates leading to aliphatic hydroxylation and epoxidation products, but the origin of this regioselectivity is poorly understood. We have synthesized a model complex and studied it with low-pressure Fourier transform-ion cyclotron resonance (FT-ICR) mass spectrometry (MS). A novel approach was devised using the reaction of [FeIII(TPFPP)]+ (TPFPP = meso-tetrakis(pentafluorophenyl)porphinato dianion) with iodosylbenzene as a terminal oxidant which leads to the production of ions corresponding to [FeIV(O)(TPFPP+˙)]+. This species was isolated in the gas-phase and studied in its reactivity with a variety of olefins. Product patterns and rate constants under Ideal Gas conditions were determined by FT-ICR MS. All substrates react with [FeIV(O)(TPFPP+˙)]+ by a more or less efficient oxygen atom transfer process. In addition, substrates with low ionization energies react by a charge-transfer channel, which enabled us to determine the electron affinity of [FeIV(O)(TPFPP+˙)]+ for the first time. Interestingly, no hydrogen atom abstraction pathways are observed for the reaction of [FeIV(O)(TPFPP+˙)]+ with prototypical olefins such as propene, cyclohexene and cyclohexadiene and also no kinetic isotope effect in the reaction rate is found, which suggests that the competition between epoxidation and hydroxylation – in the gas-phase – is in favour of substrate epoxidation. This notion further implies that P450 enzymes will need to adapt their substrate binding pocket, in order to enable favourable aliphatic hydroxylation over double bond epoxidation pathways. The MS studies yield a large test-set of experimental reaction rates of iron(iv)–oxo porphyrin cation radical complexes, so far unprecedented in the gas-phase, providing a benchmark for calibration studies using computational techniques. Preliminary computational results presented here confirm the observed trends excellently and rationalize the reactivities within the framework of thermochemical considerations and valence bond schemes.
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Affiliation(s)
- Mala A Sainna
- Manchester Institute of Biotechnology and School of Chemical Engineering and Analytical Science , The University of Manchester , 131 Princess Street , Manchester M1 7DN , UK .
| | - Suresh Kumar
- Department of Applied Physics , School for Physical Sciences , Babasaheb Bhimrao Ambedkar University , Vidya Vihar, Rai Bareilly Road , Lucknow 226 025 , India .
| | - Devesh Kumar
- Department of Applied Physics , School for Physical Sciences , Babasaheb Bhimrao Ambedkar University , Vidya Vihar, Rai Bareilly Road , Lucknow 226 025 , India .
| | - Simonetta Fornarini
- Dipartimento di Chimica e Tecnologie del Farmaco , Università di Roma "La Sapienza" , P.le A. Moro 5 , 00185 , Roma , Italy . ;
| | - Maria Elisa Crestoni
- Dipartimento di Chimica e Tecnologie del Farmaco , Università di Roma "La Sapienza" , P.le A. Moro 5 , 00185 , Roma , Italy . ;
| | - Sam P de Visser
- Manchester Institute of Biotechnology and School of Chemical Engineering and Analytical Science , The University of Manchester , 131 Princess Street , Manchester M1 7DN , UK .
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14
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Rydberg P, Lonsdale R, Harvey JN, Mulholland AJ, Olsen L. Trends in predicted chemoselectivity of cytochrome P450 oxidation: B3LYP barrier heights for epoxidation and hydroxylation reactions. J Mol Graph Model 2014; 52:30-5. [PMID: 25000094 DOI: 10.1016/j.jmgm.2014.06.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 06/11/2014] [Accepted: 06/12/2014] [Indexed: 01/19/2023]
Abstract
Prediction of epoxide formation in drug metabolism is a difficult but important task, as epoxide formation is linked to drug toxicity. A comparison of the energy barriers for cytochrome P450 mediated epoxidation of alkenes to the barriers for the hydroxylation of an aliphatic carbon atom next to a double bond has been performed using B3LYP and B3LYP-D3. Relevant experimental data on oxidation selectivity has also been assessed. The results show that density functional theory, when using B3LYP-D3, does well in reproducing the experimental trends. Considering that the comparison involves chemical steps with quite different features this is remarkable. We also find that B3LYP consistently underestimates the hydrogen abstraction barriers relative to the epoxidation barriers, and that including a dispersion correction reduces this problem.
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Affiliation(s)
- Patrik Rydberg
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Richard Lonsdale
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Jeremy N Harvey
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Adrian J Mulholland
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Lars Olsen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark.
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15
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Khade RL, Fan W, Ling Y, Yang L, Oldfield E, Zhang Y. Iron porphyrin carbenes as catalytic intermediates: structures, Mössbauer and NMR spectroscopic properties, and bonding. Angew Chem Int Ed Engl 2014; 53:7574-8. [PMID: 24910004 DOI: 10.1002/anie.201402472] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Revised: 04/08/2014] [Indexed: 11/07/2022]
Abstract
Iron porphyrin carbenes (IPCs) are thought to be intermediates involved in the metabolism of various xenobiotics by cytochrome P450, as well as in chemical reactions catalyzed by metalloporphyrins and engineered P450s. While early work proposed IPCs to contain Fe(II), more recent work invokes a double-bond description of the iron-carbon bond, similar to that found in Fe(IV) porphyrin oxenes. Reported herein is the first quantum chemical investigation of IPC Mössbauer and NMR spectroscopic properties, as well as their electronic structures, together with comparisons to ferrous heme proteins and an Fe(IV) oxene model. The results provide the first accurate predictions of the experimental spectroscopic observables as well as the first theoretical explanation of their electrophilic nature, as deduced from experiment. The preferred resonance structure is Fe(II)←{:C(X)Y}(0) and not Fe(IV)={C(X)Y}(2-), a result that will facilitate research on IPC reactivities in various chemical and biochemical systems.
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Affiliation(s)
- Rahul L Khade
- Department of Chemistry, Chemical Biology, and Biomedical, Engineering, Stevens Institute of Technology, Castle Point on Hudson, Hoboken, NJ 07030 (USA)
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16
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Khade RL, Fan W, Ling Y, Yang L, Oldfield E, Zhang Y. Iron Porphyrin Carbenes as Catalytic Intermediates: Structures, Mössbauer and NMR Spectroscopic Properties, and Bonding. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201402472] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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17
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Russell SK, Hoyt JM, Bart SC, Milsmann C, Stieber SCE, Semproni SP, DeBeer S, Chirik PJ. Synthesis, electronic structure and reactivity of bis(imino)pyridine iron carbene complexes: evidence for a carbene radical. Chem Sci 2014. [DOI: 10.1039/c3sc52450g] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The reactivity of the disubstituted diazoalkane, N2CPh2 with a family of bis(imino)pyridine iron dinitrogen complexes was examined.
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Affiliation(s)
| | - Jordan M. Hoyt
- Department of Chemistry
- Princeton University
- Princeton, USA
| | - Suzanne C. Bart
- Department of Chemistry and Chemical Biology
- Cornell University Ithaca
- , USA
| | | | | | | | - Serena DeBeer
- Department of Chemistry and Chemical Biology
- Cornell University Ithaca
- , USA
- Max-Planck Institute for Chemical Energy Conversion
- D-45470 Mülheim an der Ruhr, Germany
| | - Paul J. Chirik
- Department of Chemistry
- Princeton University
- Princeton, USA
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18
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Cheng SH, Chen YS, Su YO. Electrochemical and Spectral Studies of Sterically Hindered Water-Soluble Iron Tetrakis(Sulfonatomesityl)Porphine. J CHIN CHEM SOC-TAIP 2013. [DOI: 10.1002/jccs.199100003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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19
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Kumar D, Latifi R, Kumar S, Rybak-Akimova EV, Sainna MA, de Visser SP. Rationalization of the Barrier Height for p-Z-styrene Epoxidation by Iron(IV)-Oxo Porphyrin Cation Radicals with Variable Axial Ligands. Inorg Chem 2013; 52:7968-79. [DOI: 10.1021/ic4005104] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Devesh Kumar
- Department of Applied Physics, School of Physical Sciences, Babasaheb Bhimrao Ambedkar University, Vidya Vihar,
Rae Bareilly Road, Lucknow 226-025, India
| | - Reza Latifi
- Manchester Institute of Biotechnology and School
of Chemical Engineering and Analytical Science, University of Manchester, 131 Princess Street, Manchester M1 7DN,
U.K
- Department of Chemistry, Tufts University, Medford, Massachusetts 02155, United
States
| | - Suresh Kumar
- Department of Applied Physics, School of Physical Sciences, Babasaheb Bhimrao Ambedkar University, Vidya Vihar,
Rae Bareilly Road, Lucknow 226-025, India
| | | | - Mala A. Sainna
- Manchester Institute of Biotechnology and School
of Chemical Engineering and Analytical Science, University of Manchester, 131 Princess Street, Manchester M1 7DN,
U.K
| | - Sam P. de Visser
- Manchester Institute of Biotechnology and School
of Chemical Engineering and Analytical Science, University of Manchester, 131 Princess Street, Manchester M1 7DN,
U.K
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Lonsdale R, Harvey JN, Mulholland AJ. Effects of Dispersion in Density Functional Based Quantum Mechanical/Molecular Mechanical Calculations on Cytochrome P450 Catalyzed Reactions. J Chem Theory Comput 2012; 8:4637-45. [PMID: 26605619 DOI: 10.1021/ct300329h] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Density functional theory (DFT) based quantum mechanical/molecular mechanical (QM/MM) calculations have provided valuable insight into the reactivity of the cytochrome P450 family of enzymes (P450s). A failure of commonly used DFT methods, such as B3LYP, is the neglect of dispersion interactions. An empirical dispersion correction has been shown to improve the accuracy of gas phase DFT calculations of P450s. The current work examines the effect of the dispersion correction in QM/MM calculations on P450s. The hydrogen abstraction from camphor, and hydrogen abstraction and C-O addition of cyclohexene and propene by P450cam have been modeled, along with the addition of benzene to Compound I in CYP2C9, at the B3LYP-D2/CHARMM27 level of theory. Single point energy calculations were also performed at the B3LYP-D3//B3LYP-D2/CHARMM27 level. The dispersion corrections lower activation energy barriers significantly (by ∼5 kcal/mol), as seen for gas phase calculations, but has a small effect on optimized geometries.These effects are likely to be important in modeling reactions catalyzed by other enzymes also. Given the low computational cost of including such dispersion corrections, we recommend doing so in all B3LYP based QM/MM calculations.
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Affiliation(s)
- Richard Lonsdale
- Centre for Computational Chemistry, School of Chemistry, University of Bristol , Cantock's Close, Bristol BS8 1TS, U.K
| | - Jeremy N Harvey
- Centre for Computational Chemistry, School of Chemistry, University of Bristol , Cantock's Close, Bristol BS8 1TS, U.K
| | - Adrian J Mulholland
- Centre for Computational Chemistry, School of Chemistry, University of Bristol , Cantock's Close, Bristol BS8 1TS, U.K
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21
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de Visser SP. Predictive studies of oxygen atom transfer reactions by Compound I of cytochrome P450. ADVANCES IN INORGANIC CHEMISTRY 2012. [DOI: 10.1016/b978-0-12-396462-5.00001-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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22
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Singh A, Agarwala A, Kamaraj K, Bandyopadhyay D. The mechanistic aspects of iron(III) porphyrin catalyzed oxidation reactions in mixed solvents. Inorganica Chim Acta 2011. [DOI: 10.1016/j.ica.2011.02.054] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Kumar D, Karamzadeh B, Sastry GN, de Visser SP. What factors influence the rate constant of substrate epoxidation by compound I of cytochrome P450 and analogous iron(IV)-oxo oxidants? J Am Chem Soc 2010; 132:7656-67. [PMID: 20481499 DOI: 10.1021/ja9106176] [Citation(s) in RCA: 154] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The cytochromes P450 are a versatile range of mono-oxygenase enzymes that catalyze a variety of different chemical reactions, of which the key reactions include aliphatic hydroxylation and C=C double bond epoxidation. To establish the fundamental factors that govern substrate epoxidation by these enzymes we have done a systematic density functional theory study on substrate epoxidation by the active species of P450 enzymes, namely the iron(IV)-oxo porphyrin cation radical oxidant or Compound I. We show here, for the first time, that the rate constant of substrate epoxidation, and hence the activation energy, correlates with the ionization potential of the substrate as well as with intrinsic electronic properties of the active oxidant such as the polarizability volume. To explain these findings we present an electron-transfer model for the reaction mechanism that explains the factors that determine the barrier heights and developed a valence bond (VB) curve crossing mechanism to rationalize the observed trends. In addition, we have found a correlation for substrate epoxidation reactions catalyzed by a range of heme and nonheme iron(IV)-oxo oxidants with the strength of the O-H bond in the iron-hydroxo complex, i.e. BDE(OH), which is supported by the VB model. Finally, the fundamental factors that determine the regioselectivity change between substrate hydroxylation and epoxidation are discussed. It is shown that the regioselectivity of aliphatic hydroxylation versus double bond epoxidation is not influenced by the choice of the oxidant but is purely substrate dependent.
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Affiliation(s)
- Devesh Kumar
- Molecular Modelling Group, Indian Institute of Chemical Technology, Hyderabad 500-607, India.
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Lonsdale R, Harvey JN, Mulholland AJ. Compound I Reactivity Defines Alkene Oxidation Selectivity in Cytochrome P450cam. J Phys Chem B 2009; 114:1156-62. [DOI: 10.1021/jp910127j] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Richard Lonsdale
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, United Kingdom
| | - Jeremy N. Harvey
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, United Kingdom
| | - Adrian J. Mulholland
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, United Kingdom
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Shaik S, Cohen S, Wang Y, Chen H, Kumar D, Thiel W. P450 Enzymes: Their Structure, Reactivity, and Selectivity—Modeled by QM/MM Calculations. Chem Rev 2009; 110:949-1017. [DOI: 10.1021/cr900121s] [Citation(s) in RCA: 791] [Impact Index Per Article: 52.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sason Shaik
- Institute of Chemistry and the Lise-Meitner-Minerva Center for Computational Quantum Chemistry, The Hebrew University of Jerusalem, 91904 Jerusalem, Israel, and Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
| | - Shimrit Cohen
- Institute of Chemistry and the Lise-Meitner-Minerva Center for Computational Quantum Chemistry, The Hebrew University of Jerusalem, 91904 Jerusalem, Israel, and Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
| | - Yong Wang
- Institute of Chemistry and the Lise-Meitner-Minerva Center for Computational Quantum Chemistry, The Hebrew University of Jerusalem, 91904 Jerusalem, Israel, and Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
| | - Hui Chen
- Institute of Chemistry and the Lise-Meitner-Minerva Center for Computational Quantum Chemistry, The Hebrew University of Jerusalem, 91904 Jerusalem, Israel, and Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
| | - Devesh Kumar
- Institute of Chemistry and the Lise-Meitner-Minerva Center for Computational Quantum Chemistry, The Hebrew University of Jerusalem, 91904 Jerusalem, Israel, and Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
| | - Walter Thiel
- Institute of Chemistry and the Lise-Meitner-Minerva Center for Computational Quantum Chemistry, The Hebrew University of Jerusalem, 91904 Jerusalem, Israel, and Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
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Hata M, Tanaka Y, Kyoda N, Osakabe T, Yuki H, Ishii I, Kitada M, Neya S, Hoshino T. An epoxidation mechanism of carbamazepine by CYP3A4. Bioorg Med Chem 2008; 16:5134-48. [DOI: 10.1016/j.bmc.2008.03.023] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2008] [Revised: 03/05/2008] [Accepted: 03/06/2008] [Indexed: 11/25/2022]
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Filser JG, Hutzler C, Rampf F, Kessler W, Faller TH, Leibold E, Pütz C, Halbach S, Csanády GA. Concentrations of the Propylene Metabolite Propylene Oxide in Blood of Propylene-Exposed Rats and Humans—a Basis for Risk Assessment. Toxicol Sci 2008; 102:219-31. [DOI: 10.1093/toxsci/kfm311] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Hessenauer-Ilicheva N, Franke A, Meyer D, Woggon WD, van Eldik R. Low-Temperature Rapid-Scan Detection of Reactive Intermediates in Epoxidation Reactions Catalyzed by a New Enzyme Mimic of Cytochrome P450. J Am Chem Soc 2007; 129:12473-9. [PMID: 17880072 DOI: 10.1021/ja073266f] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The use of synthetic iron(III) porphyrins as models for heme-type catalysts in biomimetic cytochrome P450 research has provided valuable information on the nature and reactivity of intermediates produced in the "peroxide shunt" pathway. This article reports spectroscopic detection of reactive intermediates formed in the epoxidation reaction of cis-stilbene with m-chloroperoxybenzoic acid catalyzed by a new mimic of cytochrome P450 with a substituted RSO3- group (1). The application of low-temperature rapid-scan stopped-flow techniques enabled the determination of equilibrium and rate constants for the formation and decay of all intermediates in the catalytic cycle of 1, including the rate constant for the formation (1*+)FeIV=O and for oxygen transfer to the substrate. Noteworthy, the reaction of (1*+)FeIV=O with cis-stilbene leads to an almost complete re-formation (95%) of the starting complex 1. The results show that complex 1 is a valuable catalyst with promising properties for further applications in a biomimetic approach toward mimicking oxygenation reactions of cytochrome P450.
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Affiliation(s)
- Natalya Hessenauer-Ilicheva
- Institute for Inorganic Chemistry, University of Erlangen-Nürnberg, Egerlandstrasse 1, 91058 Erlangen, Germany
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30
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Simonneaux G, Le Maux P. Carbene Complexes of Heme Proteins and Iron Porphyrin Models. TOP ORGANOMETAL CHEM 2006. [DOI: 10.1007/3418_006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
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Shaik S, Kumar D, de Visser SP, Altun A, Thiel W. Theoretical Perspective on the Structure and Mechanism of Cytochrome P450 Enzymes. Chem Rev 2005; 105:2279-328. [PMID: 15941215 DOI: 10.1021/cr030722j] [Citation(s) in RCA: 954] [Impact Index Per Article: 50.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sason Shaik
- Department of Organic Chemistry and the Lise-Meitner-Minerva Center for Computational Quantum Chemistry, The Hebrew University of Jerusalem, Israel.
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33
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Huang L, Chen Y, Gao GY, Zhang XP. Diastereoselective and Enantioselective Cyclopropanation of Alkenes Catalyzed by Cobalt Porphyrins. J Org Chem 2003; 68:8179-84. [PMID: 14535801 DOI: 10.1021/jo035088o] [Citation(s) in RCA: 118] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cobalt(II) porphyrin complexes were shown to be general and efficient catalysts for selective cyclopropanation of alkenes with ethyl diazoacetate (EDA). The catalytic system can operate with alkenes as limiting reagents, requiring only stoichiometric amounts of EDA. The protocol is performed in one-pot fashion without the need of slow addition of EDA. The diastereoselectivity of the current system can be tuned by using different porphyrin ligands or additives, giving either trans- or cis-dominant cyclopropanes. The asymmetric cyclopropanation was also demonstrated with the use of chiral cobalt porphyrin complexes.
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Affiliation(s)
- Lingyu Huang
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996-1600, USA
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34
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Leriche C, He X, Chang CWT, Liu HW. Reversal of the apparent regiospecificity of NAD(P)H-dependent hydride transfer: the properties of the difluoromethylene group, a carbonyl mimic. J Am Chem Soc 2003; 125:6348-9. [PMID: 12785757 DOI: 10.1021/ja021487+] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The hallmarks of pyridine nucleotide-dependent dehydrogenase reactions are the stereo- and regiospecific hydride transfer between the nicotinamide coenzyme and the corresponding substrate. When the hydride is delivered from NAD(P)H to reduce the keto-substrate, the site of attack is always at the carbonyl carbon. However, the apparent regioselectivity of the hydride transfer is reversed when difluoromethylene is used as a carbonyl mimic in the NADH-dependent enzyme, TDP-l-rhamnose synthase, which catalyzes the conversion of TDP-6-deoxy-l-lyxo-4-hexulose to TDP-l-rhamnose. The observed reversed regioselectivity can be explained by two mechanisms. One involves the formation of a carbene intermediate followed by a rearrangement involving 1,2-H shift. This mechanistic proposal is theoretically sound and would represent a rare example implicating the intermediacy of a carbene species in an enzyme reaction. However, our results are also consistent with a second mechanism in which the hydride addition to the difluoromethylene moiety occurs at the difluorinated end, opposite from the site predicted on the basis of the reduction of a normal keto functional group. Such a regioselectivity is well precedented in chemical models because nucleophilic addition to fluoroalkenes prefers a route in which the number of fluorines beta to the electron-rich carbon in the transition state is maximized. In this mechanism, the difluoromethylene group may be regarded as a carbonyl mimic with reversed polarity in enzyme catalysis. While further experiments are needed to discriminate between these mechanistic possibilities, the results reported here suggest that the apparent regioselectivity of hydride transfer in a pyridine nucleotide-dependent enzyme can be changed by altering the electrochemical properties of the reaction center.
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Affiliation(s)
- Caroline Leriche
- Division of Medicinal Chemistry, College of Pharmacy, and Department of Chemistry and Biochemistry, University of Texas, Austin, Texas 78712, USA
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35
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Guengerich FP. Cytochrome P450 oxidations in the generation of reactive electrophiles: epoxidation and related reactions. Arch Biochem Biophys 2003; 409:59-71. [PMID: 12464245 DOI: 10.1016/s0003-9861(02)00415-0] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Much of the interest in the cytochrome P450 (P450) enzymes has been because of oxidation of chemicals to reactive products. The epoxides (oxiranes) have been a major topic of interest with olefins and aryl compounds. Epoxides vary considerably in their reactivity, with t(1/2) varying from 1s to several hours. The stability and reactivity influences not only the overall damage to biological systems but also the site of injury. Transformations of some xenobiotic chemicals may involve products other than epoxides. Chemicals considered here include olefins, aromatic hydrocarbons, heterocycles, vinyl halides, ethyl carbamate, vinyl nitrosamines, and aflatoxin B(1). These compounds either are unsaturated or are transformed to unsaturated products. The epoxides and other products provide a view of the landscape of P450-generated reactive products and the myriad of chemistry involved in the metabolism of drugs and protoxicants. Understanding the chemical nature of reactive products is necessary to develop rational strategies for intervention.
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Affiliation(s)
- F Peter Guengerich
- Department of Biochemistry and Center in Molecular Toxicology, School of Medicine, Vanderbilt University, 638 Robinson Research Building, 23rd and Pierce Avenues, Nashville, TN 37232-0146, USA.
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Li Y, Huang JS, Zhou ZY, Che CM, You XZ. Remarkably stable iron porphyrins bearing nonheteroatom-stabilized carbene or (alkoxycarbonyl)carbenes: isolation, X-ray crystal structures, and carbon atom transfer reactions with hydrocarbons. J Am Chem Soc 2002; 124:13185-93. [PMID: 12405847 DOI: 10.1021/ja020391c] [Citation(s) in RCA: 163] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Reactions of [Fe(TPFPP)] (TPFPP = meso-tetrakis(pentafluorophenyl)porphyrinato dianion) with diazo compounds N(2)C(Ph)R (R = Ph, CO(2)Et, CO(2)CH(2)CH=CH(2)) afforded [Fe(TPFPP)(C(Ph)R)] (R = Ph (1), CO(2)Et (2), CO(2)CH(2)CH=CH(2) (3)) in 65-70% yields. Treatment of 1 with N-methylimidazole (MeIm) gave the adduct [Fe(TPFPP)(CPh(2))(MeIm)] (4) in 65% yield. These new iron porphyrin carbene complexes were characterized by NMR and UV-vis spectroscopy, mass spectrometry, and elemental analyses. X-ray crystal structure determinations of 1.0.5C(6)H(6).0.5CH(2)Cl(2) and 4 reveal Fe=CPh(2) bond lengths of 1.767(3) (1) and 1.827(5) A (4), together with large ruffling distortions of the TPFPP macrocycle. Complexes 2 and 4 are reactive toward styrene, affording the corresponding cyclopropanes in 82 and 53% yields, respectively. Complex 1 is an active catalyst for both intermolecular cyclopropanation of styrenes with ethyl diazoacetate and intramolecular cyclopropanation of allylic diazoacetates. Reactions of 2 and 4 with cyclohexene or cumene produced allylic or benzylic C-H insertion products in up to 83% yield.
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Affiliation(s)
- Yan Li
- Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong Kong, Pokfulam Road, Hong Kong
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de Visser SP, Ogliaro F, Sharma PK, Shaik S. What Factors Affect the Regioselectivity of Oxidation by Cytochrome P450? A DFT Study of Allylic Hydroxylation and Double Bond Epoxidation in a Model Reaction. J Am Chem Soc 2002; 124:11809-26. [PMID: 12296749 DOI: 10.1021/ja026872d] [Citation(s) in RCA: 249] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Epoxidation (C=C) vis-à-vis allylic hydroxylation (C-H) reactions of propene with a model compound I (Cpd I) of the enzyme cytochrome P450 were studied using B3LYP density functional theory. Potential energy profiles and kinetic isotope effects (KIE) were calculated. The interactions in the protein pocket were mimicked by adding two external NH- - -S hydrogen bonds to the thiolate ligand and by introducing a nonpolar medium (with a dielectric constant, epsilon = 5.7) that can exert a polarization effect on the reacting species. A two-state reactivity (TSR) with high-spin (HS) and low-spin (LS) states were located for both processes (Ogliaro, F.; Harris, N.; Cohen, S.; Filatov, M.; de Visser, S. P.; Shaik, S. J. Am. Chem. Soc. 2000, 122, 8977-8989. de Visser, S. P.; Ogilaro, F.; Harris, N.; Shaik, S. J. Am. Chem. Soc. 2001, 123, 3037-3047). The HS processes were found to be stepwise, whereas the LS processes were characterized as nonsynchronous but effectively concerted pathways. The computed KIE for C-H hydroxylation with and without tunneling corrections are large (>7), and they support the assignment of the corresponding transition states as hydrogen-abstraction species (Groves, J. T.; Han, Y.-Z. In Cytochrome P450: Structures, Mechanism and Biochemistry, 2nd ed.; Ortiz de Montellano, P. R., Ed.; Plenum Press: New York, 1995; Chapter 1; pp 3-48). In the gas phase, epoxidation is energetically favorable by 3.4 kcal mol(-1). Inclusion of zero-point energy reduces this difference but still predicts C=C/C-H > 1. Environmental effects were found to have major impact on the C=C/C-H ratio as well as on the stereoselectivity of the processes. Thus, two NH- - -S hydrogen bonds away from the reaction center reverse the regioselectivity and prefer hydroxylation, namely, C=C/C-H <1. The polarity of the medium further accentuates the trend and leads to a change by 2 orders of magnitude in the regioselectivity, C=C/C-H << 1. Furthermore, since the environmental interactions prefer the LS over the HS reactions, both hydroxylation and epoxidation processes are rendered more stereoselective, again by 2 orders of magnitude. It follows, therefore, that Cpd I is a chameleon oxidant (Ogliaro, F.; Cohen, S.; de Visser, S. P.; Shaik, S. J. Am. Chem. Soc. 2000, 122, 12892-12893; Ogliaro, F.; de Visser, S. P.; Cohen, S.; Kaneti, J.; Shaik, S. Chembiochem. 2001, 2, 848-851; Ogliaro, F.; de Visser, S. P.; Groves, J. T.; Shaik, S. Angew. Chem., Int. Ed. 2001, 40, 2874-2878) that tunes its reactivity and selectivity patterns in response to the protein environment in which it is accommodated. A valence bond (VB) model, akin to "redox mesomerism" (Bernadou, J.; Fabiano, A.-S.; Robert, A.; Meunier, B. J. Am. Chem. Soc. 1994, 116, 9375-9376), is constructed and enables the description of a chameleon transition state. It shows that the good donor ability of the thiolate ligand and the acceptor ability of the iron porphyrin create mixed-valent situations that endow the transition state with a great sensitivity to external perturbations as in the protein pocket. The model is used to discuss the computed results and to relate them to experimental findings.
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Affiliation(s)
- Sam P de Visser
- Department of Organic Chemistry, The Lise Meitner-Minerva Center for Computational Quantum Chemistry, The Hebrew University of Jerusalem, 91904 Jerusalem, Israel
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de Visser SP, Ogliaro F, Shaik S. How Does Ethene Inactivate Cytochrome P450 En Route to Its Epoxidation? A Density Functional Study. Angew Chem Int Ed Engl 2001; 40:2871-2874. [DOI: 10.1002/1521-3773(20010803)40:15<2871::aid-anie2871>3.0.co;2-r] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2000] [Indexed: 11/11/2022]
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de Visser SP, Ogliaro F, Shaik S. How Does Ethene Inactivate Cytochrome P450 En Route to Its Epoxidation? A Density Functional Study. Angew Chem Int Ed Engl 2001. [DOI: 10.1002/1521-3757(20010803)113:15<2955::aid-ange2955>3.0.co;2-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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40
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Ishii S, Zhao S, Mehta G, Knors CJ, Helquist P. Intramolecular C−H Insertion Reactions of (η5-Cyclopentadienyl)dicarbonyliron Carbene Complexes: Scope of the Reactions and Application to the Synthesis of (±)-Sterpurene and (±)-Pentalenene. J Org Chem 2001; 66:3449-58. [PMID: 11348129 DOI: 10.1021/jo001792i] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
(eta(5)-Cyclopentadienyl)dicarbonyliron carbene complexes, [(eta(5)-C(5)H(5))(CO)(2)Fe=CHR](+)BF(4)(-), are generated as reactive intermediates from thioether derivatives, (eta(5)-C(5)H(5))(CO)(2)FeCH(R)SPh, by S-alkylation with trimethyloxonium tetrafluoroborate and loss of thioanisole. The carbene complexes undergo intramolecular C-H insertion into appropriately situated side chains to form cyclopentane derivatives. The reaction has been developed into a general procedure employing cycloalkanones as scaffolds bearing the iron carbene moieties and the side chains at C(2) and C(3), respectively. The products of the intramolecular insertion reactions are substituted bicyclo[n.3.0]alkanones. The scope and limitations of the reaction are described. The reaction is applied to a total synthesis of sterpurene and to a formal synthesis of pentalenene. Overall, this approach to cyclopentane annulation complements the related metal-catalyzed insertion reactions of diazocarbonyl compounds, which are also believed to occur via metal carbene complexes.
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Affiliation(s)
- S Ishii
- Department of Chemistry and Biochemistry, 251 Nieuwland Science Hall, University of Notre Dame, Notre Dame, IN 46556, USA
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Tormo J, Moyano A, Pericàs MA, Riera A. Enantioselective Construction of Angular Triquinanes through an Asymmetric Intramolecular Pauson−Khand Reaction. Synthesis of (+)-15-Nor-pentalenene. J Org Chem 1997. [DOI: 10.1021/jo9700538] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jordi Tormo
- Departament de Química Orgànica, Universitat de Barcelona, c/ Martí i Franquès 1-11, 08028 Barcelona, Spain
| | - Albert Moyano
- Departament de Química Orgànica, Universitat de Barcelona, c/ Martí i Franquès 1-11, 08028 Barcelona, Spain
| | - Miquel A. Pericàs
- Departament de Química Orgànica, Universitat de Barcelona, c/ Martí i Franquès 1-11, 08028 Barcelona, Spain
| | - Antoni Riera
- Departament de Química Orgànica, Universitat de Barcelona, c/ Martí i Franquès 1-11, 08028 Barcelona, Spain
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Affiliation(s)
- Masanori Sono
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208
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Oliw EH, Bylund J, Herman C. Bisallylic hydroxylation and epoxidation of polyunsaturated fatty acids by cytochrome P450. Lipids 1996; 31:1003-21. [PMID: 8898299 DOI: 10.1007/bf02522457] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Polyunsaturated fatty acids can be oxygenated by cytochrome P450 to hydroxy and epoxy fatty acids. Two major classes of hydroxy fatty acids are formed by hydroxylation of the omega-side chain and by hydroxylation of bisallylic methylene carbons. Bisallylic cytochrome P450-hydroxylases transform linoleic acid to 11-hydroxylinoleic acid, arachidonic acid to 13-hydroxyeicosa-5Z,8Z,11Z,14Z-tetraenoic acid, 10-hydroxyeicosa-5Z,8Z,11Z,14Z-tetraenoic acid and 7-hydroxyeicosa-5Z,8Z,11Z,14Z-tetraenoic acid and eicosapentaenoic acid to 16-hydroxyeicosa-5Z,8Z,11Z,14Z,17Z-pent aenoic acid, 13-hydroxyeicosa-5Z,8Z,11Z,14Z,17Z-pent aenoic acid and 10-hydroxyeicosa-5Z,8Z,11Z,14Z,17Z-pent aenoic acid as major metabolites. The bisallylic hydroxy fatty acids are chemically unstable and decompose rapidly to cis-trans conjugated hydroxy fatty acids during acidic extractive isolation. Bisallylic hydroxylase activity appears to be augmented in microsomes induced by the synthetic glucocorticoid dexamethasone and by some other agents, but the P450 gene families of these hydroxylases have yet to be determined. The fatty acid epoxides, which are formed by cytochrome P450, are chemically stable, but are hydrolyzed to diols by soluble epoxide hydrolases. Epoxidation of polyunsaturated fatty acids is a prominent pathway of metabolism in the liver and the renal cortex and epoxy-genase activity appears to be under homeostatic control in the kidney. Many arachidonate epoxygenases have been identified belonging to the CYP2C gene subfamily. Epoxygenases have also been found in the central nervous system, endocrine organs, the heart and endothelial cells. Epoxides of arachidonic acid have been found to exert pharmacological effects on many cells.
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Affiliation(s)
- E H Oliw
- Department of Pharmaceutical Biosciences, Uppsala University Biomedical Center, Sweden
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Czarnecki K, Nimri S, Gross Z, Proniewicz LM, Kincaid JR. Direct Resonance Raman Evidence for a Trans Influence on the Ferryl Fragment in Models of Compound I Intermediates of Heme Enzymes. J Am Chem Soc 1996. [DOI: 10.1021/ja952177c] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Kazimierz Czarnecki
- Chemistry Department, Marquette University, Milwaukee, Wisconsin 53201-1881, Department of Chemistry, Israel Institute of Technology, Technion City, Haifa 32000, Israel, and Chemical Physics Division, Department of Chemistry, and Regional Laboratory of Physicochemical Analysis and Structural Research, Jagiellonian University, R. Ingardena Street 3, 30-060 Krakow, Poland
| | - Shay Nimri
- Chemistry Department, Marquette University, Milwaukee, Wisconsin 53201-1881, Department of Chemistry, Israel Institute of Technology, Technion City, Haifa 32000, Israel, and Chemical Physics Division, Department of Chemistry, and Regional Laboratory of Physicochemical Analysis and Structural Research, Jagiellonian University, R. Ingardena Street 3, 30-060 Krakow, Poland
| | - Zeev Gross
- Chemistry Department, Marquette University, Milwaukee, Wisconsin 53201-1881, Department of Chemistry, Israel Institute of Technology, Technion City, Haifa 32000, Israel, and Chemical Physics Division, Department of Chemistry, and Regional Laboratory of Physicochemical Analysis and Structural Research, Jagiellonian University, R. Ingardena Street 3, 30-060 Krakow, Poland
| | - Leonard M. Proniewicz
- Chemistry Department, Marquette University, Milwaukee, Wisconsin 53201-1881, Department of Chemistry, Israel Institute of Technology, Technion City, Haifa 32000, Israel, and Chemical Physics Division, Department of Chemistry, and Regional Laboratory of Physicochemical Analysis and Structural Research, Jagiellonian University, R. Ingardena Street 3, 30-060 Krakow, Poland
| | - James R. Kincaid
- Chemistry Department, Marquette University, Milwaukee, Wisconsin 53201-1881, Department of Chemistry, Israel Institute of Technology, Technion City, Haifa 32000, Israel, and Chemical Physics Division, Department of Chemistry, and Regional Laboratory of Physicochemical Analysis and Structural Research, Jagiellonian University, R. Ingardena Street 3, 30-060 Krakow, Poland
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Schröder D, Schwarz H. Aktivierung von CH- und CC-Bindungen durch „nackte” Übergangsmetalloxid-Kationen in der Gasphase. Angew Chem Int Ed Engl 1995. [DOI: 10.1002/ange.19951071805] [Citation(s) in RCA: 126] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Liu KE, Lippard SJ. Studies of the Soluble Methane Monooxygenase Protein System: Structure, Component Interactions, and Hydroxylation Mechanism. ADVANCES IN INORGANIC CHEMISTRY 1995. [DOI: 10.1016/s0898-8838(08)60054-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Abstract
Polyunsaturated fatty acids can be oxygenated by P450 in different ways--by epoxidation, by hydroxylation of the omega-side chain, by allylic and bis-allylic hydroxylation and by hydroxylation with double bond migration. Major organs for these oxygenations are the liver and the kidney. P450 is an ubiquitous enzyme. It is therefore not surprising that some of these reactions have been found in other organs and tissues. Many observations indicate that P450 oxygenates arachidonic acid in vivo in man and in experimental animals. This is hardly surprising. omega-Oxidation was discovered in vivo 60 years ago. It was more unexpected that biological activities have been associated with many of the P450 metabolites of arachidonic acid, at least in pharmacological doses. Epoxygenase metabolites of arachidonic acid have attracted the largest interest. In their critical review on epoxygenase metabolism of arachidonic acid in 1989, Fitzpatrick and Murphy pointed out some major differences between the PGH synthase, the lipoxygenase and the P450 pathways of arachidonic acid metabolism. Their main points are still valid and have only to be modified slightly in the light of recent results. First, lipoxygenases show a marked regiospecificity and stereospecificity, while many P450 seem to lack this specificity. There are, however, P450 isozymes which catalyse stereospecific epoxidations or hydroxylations. Many hydroxylases and at least some epoxygenases also show regiospecificity, i.e. oxygenate only one double bond or one specific carbon of the fatty acid substrate. In addition, preference for arachidonic acid and eicosapentaenoic acid may occur in the sense that other fatty acids are oxygenated with less regiospecificity. A more important difference is that prostaglandins and leukotrienes affect specific and well characterised receptors in cell membranes, while receptors for epoxides of arachidonic acid or other P450 metabolites have not been characterised. Nevertheless, epoxides of arachidonic acid have been found to induce a large number of different pharmacological effects. In some systems, effects have been noted at pm concentrations which might conceivably be in the physiological concentration range of these epoxides, e.g. after release from phospholipids by phospholipase A2. An intriguing possibility is that the effects of [Ca]i on different ion channels might possibly explain their biological actions. In situations when pharmacological doses are used, metabolism to epoxyprostanoids or other interactions with PGH synthase could also be of importance. Finally, one report on a specific receptor for 14R,15S-EpETrE in mononuclear cell membranes has just been published.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- E H Oliw
- Department of Pharmaceutical Biosciences, Uppsala University, Sweden
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