1
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Wang Q, Jiang X, Gao Y, Yin L, Wei X, Guo K, Gao X, Wang L, Zhang C. Studies on Biosynthesis of Chiral Sulfoxides by Using P450 119 Peroxygenase and Its Mutants. ChemistrySelect 2022. [DOI: 10.1002/slct.202204031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Qin Wang
- Department of Medicinal Chemistry School of Pharmacy Southwest Medical University No. 1, Section 1, XiangLin road, Longmatan District Luzhou 646000 China
- Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province The Affiliated Hospital of Southwest Medical University No. 25 Taiping road, Jiangyang District Luzhou 646000 China
- Dazhou Vocational College of Chinese Medicine Luojiang Town, Tongchuan District Dazhou 635000 China
| | - Xin‐Meng Jiang
- Department of Medicinal Chemistry School of Pharmacy Southwest Medical University No. 1, Section 1, XiangLin road, Longmatan District Luzhou 646000 China
- Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province The Affiliated Hospital of Southwest Medical University No. 25 Taiping road, Jiangyang District Luzhou 646000 China
| | - Yan‐Ping Gao
- Department of Medicinal Chemistry School of Pharmacy Southwest Medical University No. 1, Section 1, XiangLin road, Longmatan District Luzhou 646000 China
| | - Li‐Ping Yin
- Department of Medicinal Chemistry School of Pharmacy Southwest Medical University No. 1, Section 1, XiangLin road, Longmatan District Luzhou 646000 China
- Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province The Affiliated Hospital of Southwest Medical University No. 25 Taiping road, Jiangyang District Luzhou 646000 China
| | - Xiao‐Yao Wei
- Department of Medicinal Chemistry School of Pharmacy Southwest Medical University No. 1, Section 1, XiangLin road, Longmatan District Luzhou 646000 China
| | - Kai Guo
- Department of Medicinal Chemistry School of Pharmacy Southwest Medical University No. 1, Section 1, XiangLin road, Longmatan District Luzhou 646000 China
| | - Xiao‐Wei Gao
- Department of Medicinal Chemistry School of Pharmacy Southwest Medical University No. 1, Section 1, XiangLin road, Longmatan District Luzhou 646000 China
| | - Li Wang
- Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province The Affiliated Hospital of Southwest Medical University No. 25 Taiping road, Jiangyang District Luzhou 646000 China
- Department of Nuclear Medicine The Affiliated Hospital of Southwest Medical University No. 25 Taiping road, Jiangyang District Luzhou 646000 China
| | - Chun Zhang
- Department of Medicinal Chemistry School of Pharmacy Southwest Medical University No. 1, Section 1, XiangLin road, Longmatan District Luzhou 646000 China
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2
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Itoga M, Yamanishi M, Udagawa T, Kobayashi A, Maekawa K, Takemoto Y, Naka H. Iridium-catalyzed α-selective deuteration of alcohols. Chem Sci 2022; 13:8744-8751. [PMID: 35975159 PMCID: PMC9350590 DOI: 10.1039/d2sc01805e] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 06/29/2022] [Indexed: 11/23/2022] Open
Abstract
The development of chemoselective C(sp3)-H deuteration is of particular interest in synthetic chemistry. We herein report the α-selective, iridium(iii)-bipyridonate-catalyzed hydrogen(H)/deuterium(D) isotope exchange of alcohols using deuterium oxide (D2O) as the primary deuterium source. This method enables the direct, chemoselective deuteration of primary and secondary alcohols under basic or neutral conditions without being affected by coordinative functional groups such as imidazole and tetrazole. Successful substrates for deuterium labelling include the pharmaceuticals losartan potassium, rapidosept, guaifenesin, and diprophylline. The deuterated losartan potassium shows higher stability towards the metabolism by CYP2C9 than the protiated analogue. Kinetic and DFT studies indicate that the direct deuteration proceeds through dehydrogenation of alcohol to the carbonyl intermediate, conversion of [IrIII-H] to [IrIII-D] with D2O, and deuteration of the carbonyl intermediate to give the α-deuterated product.
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Affiliation(s)
- Moeko Itoga
- Graduate School of Pharmaceutical Sciences, Kyoto University Kyoto 606-8501 Japan
| | - Masako Yamanishi
- Graduate School of Pharmaceutical Sciences, Kyoto University Kyoto 606-8501 Japan
| | - Taro Udagawa
- Department of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University Yanagido 1-1 Gifu 501-1193 Japan
| | - Ayane Kobayashi
- Faculty of Pharmaceutical Sciences, Doshisha Women's College of Liberal Arts Kodo, Kyotanabe Kyoto 610-0395 Japan
| | - Keiko Maekawa
- Faculty of Pharmaceutical Sciences, Doshisha Women's College of Liberal Arts Kodo, Kyotanabe Kyoto 610-0395 Japan
| | - Yoshiji Takemoto
- Graduate School of Pharmaceutical Sciences, Kyoto University Kyoto 606-8501 Japan
| | - Hiroshi Naka
- Graduate School of Pharmaceutical Sciences, Kyoto University Kyoto 606-8501 Japan
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3
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Kuiry H, Das D, Das S, Chakraborty S, Chandra B, Gupta SS. Electrocatalytic alcohol oxidation by a molecular iron complex. Faraday Discuss 2022; 234:42-57. [PMID: 35174376 DOI: 10.1039/d1fd00074h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An efficient electrochemical method for the selective oxidation of alcohols to their corresponding aldehydes/ketones using a biomimetic iron complex, [(bTAML)FeIII-OH2]-, as the redox mediator in an undivided electrochemical cell with inexpensive carbon and nickel electrodes using water as an oxygen source is reported. The substrate scope also includes alcohols that contain O and N heteroatoms in the scaffold, which are well tolerated under these reaction conditions. Mechanistic studies show the involvement of a high-valent FeV(O) species, [(bTAML)FeV(O)]-, formed via PCET (overall 2H+/2e-) from [(bTAML)FeIII-OH2]- at 0.77 V (vs. Fc+/Fc). Moreover, electrokinetic studies of the oxidation of C-H bonds indicate a second-order reaction, with the C-H abstraction by FeV(O) being the rate-determining step. The overall mechanism, studied using linear free energy relationships and radical clocks, indicates a "net hydride" transfer, leading to the oxidation of the alcohol to the corresponding aldehyde or ketone. When the reaction was carried out at pH > 11, the reaction could be carried out at a ∼500 mV lower potential than that at pH 8, albeit with reduced reaction rates. The reactive intermediate involved at pH > 11 is the corresponding one-electron oxidized [(bTAML)FeIV(O)]2- species.
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Affiliation(s)
- Himangshu Kuiry
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal, India-741246.
| | - Debasree Das
- Chemical Engineering and Process Development Division, CSIR-National Chemical Laboratory, Pune, Maharashtra-411008, India
| | - Soumadip Das
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal, India-741246.
| | - Soham Chakraborty
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal, India-741246.
| | - Bittu Chandra
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal, India-741246.
| | - Sayam Sen Gupta
- Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal, India-741246.
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4
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Ishimizu Y, Ma Z, Hada M, Fujii H. Rate-Limiting Step of Epoxidation Reaction of the Oxoiron(IV) Porphyrin π-Cation Radical Complex: Electron Transfer Coupled Bond Formation Mechanism. Inorg Chem 2021; 60:17687-17698. [PMID: 34775756 DOI: 10.1021/acs.inorgchem.1c02287] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Epoxidation reactions catalyzed by high-valent metal-oxo species are key reactions in various biological and chemical processes. Because the redox potentials of alkenes are higher than those of most high-valent metal-oxo species, the electron transfer (ET) from the alkene to the high-valent metal-oxo species in the epoxidation reaction is endergonic and must be coupled with another exergonic process. To reveal the mechanism of the ET, we performed a Marcus plot analysis for the epoxidation reaction of the oxoiron(IV) porphyrin π-cation radical complex (compound I) with alkene. The Marcus plots can be simulated with a linear line with the gradient of 0.50 when the redox potential of compound I varies and 0.07 when the redox potential of alkene varies. These results indicate that the ET process is involved in the rate-limiting step and coupled with the following O-C bond formation process: ET coupled bond formation mechanism. The DFT calculations support this conclusion and disclose the details of the mechanism. As the alkene comes close to the oxo ligand, the energy of the highest occupied molecular orbital (HOMO) of the alkene increases and the energy for the ET becomes small enough to allow the ET. Finally, the ET occurs from the HOMO of the alkene to the porphyrin π-radical orbital. The shift of one electron from the HOMO of the alkene by the ET simultaneously results in the O-C half bond formation between the oxo ligand and the alkene. The ET process itself is still endergonic and reversible, but the bond formation coupled with the ET changes the overall process to exergonic and irreversible. We also discuss the similarity with the aromatic hydroxylation reaction and the relevance to the epoxidation reactions of other metal-oxo complexes and peracid.
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Affiliation(s)
- Yuri Ishimizu
- Department of Chemistry, Graduate School of Humanities and Sciences, Nara Women's University, Kitauoyanishi, Nara 630-8506, Japan
| | - Zhifeng Ma
- Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, 1-1 Minamiosawa, Hachioji 192-0397, Japan
| | - Masahiko Hada
- Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, 1-1 Minamiosawa, Hachioji 192-0397, Japan
| | - Hiroshi Fujii
- Department of Chemistry, Graduate School of Humanities and Sciences, Nara Women's University, Kitauoyanishi, Nara 630-8506, Japan
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5
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Fukuzumi S, Lee Y, Nam W. Deuterium kinetic isotope effects as redox mechanistic criterions. B KOREAN CHEM SOC 2021. [DOI: 10.1002/bkcs.12417] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Shunichi Fukuzumi
- Department of Chemistry and Nano Science Ewha Womans University Seoul Korea
- Faculty of Science and Engineering Meijo University Nagoya Aichi Japan
| | - Yong‐Min Lee
- Department of Chemistry and Nano Science Ewha Womans University Seoul Korea
- Research Institute for Basic Sciences Ewha Womans University Seoul Korea
| | - Wonwoo Nam
- Department of Chemistry and Nano Science Ewha Womans University Seoul Korea
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6
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Nan XL, Wang Y, Li XB, Tung CH, Wu LZ. Site-selective D 2O-mediated deuteration of diaryl alcohols via quantum dots photocatalysis. Chem Commun (Camb) 2021; 57:6768-6771. [PMID: 34132717 DOI: 10.1039/d1cc02551a] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Owing to the high synthetic value of deuteration in the pharmaceutical industry, we describe herein the conversion of a range of aromatic ketones to deuterium-labeled products in good to excellent yields. Efficient and site-selective deuteration of benzyl alcohols by D2O with visible light irradiation of quantum dots (QDs), together with gram-scale synthesis and photocatalyst recycling experiments indicated the potential of the developed method in practical organic synthesis.
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Affiliation(s)
- Xiao-Lei Nan
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, The Chinese Academy of Sciences, Beijing 100190, People's Republic of China. and School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Yao Wang
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, The Chinese Academy of Sciences, Beijing 100190, People's Republic of China. and School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Xu-Bing Li
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, The Chinese Academy of Sciences, Beijing 100190, People's Republic of China. and School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Chen-Ho Tung
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, The Chinese Academy of Sciences, Beijing 100190, People's Republic of China. and School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Li-Zhu Wu
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, The Chinese Academy of Sciences, Beijing 100190, People's Republic of China. and School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
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7
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Zhu N, Su M, Wan WM, Li Y, Bao H. Practical Method for Reductive Deuteration of Ketones with Magnesium and D 2O. Org Lett 2020; 22:991-996. [PMID: 31967845 DOI: 10.1021/acs.orglett.9b04536] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
α-Deuterated alcohols have important applications in pharmaceuticals and mechanism studies. Here, we report a new and practical strategy for the reductive deuteration of ketones using a Mg/BrCH2CH2Br/D2O system, which affords α-deuterated alcohols in good yields and with almost quantitative incorporation of deuterium. The synthetic value of this method has been demonstrated by the easy access to deuterated drugs or drug derivatives. This method may inspire the discovery of other deuterium-containing drugs.
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Affiliation(s)
- Nengbo Zhu
- State Key Laboratory of Structural Chemistry, Key Laboratory of Coal to Ethylene Glycol and Its Related Technology, Center for Excellence in Molecular Synthesis , Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , 155 Yangqiao Road West , Fuzhou , Fujian 350002 , P. R. China
| | - Min Su
- State Key Laboratory of Structural Chemistry, Key Laboratory of Coal to Ethylene Glycol and Its Related Technology, Center for Excellence in Molecular Synthesis , Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , 155 Yangqiao Road West , Fuzhou , Fujian 350002 , P. R. China
| | - Wen-Ming Wan
- State Key Laboratory of Structural Chemistry, Key Laboratory of Coal to Ethylene Glycol and Its Related Technology, Center for Excellence in Molecular Synthesis , Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , 155 Yangqiao Road West , Fuzhou , Fujian 350002 , P. R. China
| | - Yajun Li
- State Key Laboratory of Structural Chemistry, Key Laboratory of Coal to Ethylene Glycol and Its Related Technology, Center for Excellence in Molecular Synthesis , Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , 155 Yangqiao Road West , Fuzhou , Fujian 350002 , P. R. China
| | - Hongli Bao
- State Key Laboratory of Structural Chemistry, Key Laboratory of Coal to Ethylene Glycol and Its Related Technology, Center for Excellence in Molecular Synthesis , Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , 155 Yangqiao Road West , Fuzhou , Fujian 350002 , P. R. China
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8
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Hosseini-Sarvari M, Dehghani A. Visible-light-driven photochemical activity of ternary Ag/AgBr/TiO2 nanotubes for oxidation C(sp3)–H and C(sp2)–H bonds. NEW J CHEM 2020. [DOI: 10.1039/d0nj03907a] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The Ag/AgBr/TiO2 ternary nanotube as a heterogeneous photocatalyst was used for the solvent-free oxidation of the benzylic C(sp3)–H bond or the solvent-controlled selective oxidative cleavage of the CC double bond of styrene under visible light at room temperature.
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Affiliation(s)
| | - Abdulhamid Dehghani
- Department of Chemistry
- Shiraz University
- Shiraz 7194684795
- Islamic Republic of Iran
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9
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Su Z, Horner JH, Newcomb M. Cytochrome P450 119 Compounds I Formed by Chemical Oxidation and Photooxidation Are the Same Species. Chemistry 2019; 25:14015-14020. [PMID: 23108625 PMCID: PMC3930626 DOI: 10.1002/chem.201202254] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Indexed: 11/07/2022]
Abstract
Compound I from cytochrome P450 119 prepared by the photooxidation method involving peroxynitrite oxidation of the resting enzyme to Compound II followed by photooxidation to Compound I was compared to Compound I generated by m-chloroperoxybenzoic acid (MCPBA) oxidation of the resting enzyme. The two methods gave the same UV/Visible spectra, the same products from oxidations of lauric acid and palmitic acid and their (ω-2,ω-2,ω-3,ω-3)-tetradeuterated analogues, and the same kinetics for oxidations of lauric acid and caprylic acid. The experimental identities between the transients produced by the two methods leave no doubt that the same Compound I species is formed by the two methods.
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Affiliation(s)
- Zhi Su
- Department of Chemistry, University of Illinois at Chicago, 845 W. Taylor St., Chicago, IL 60617 U.S.A, Fax: (+1) 312-996-0431
| | - John H. Horner
- Department of Chemistry, University of Illinois at Chicago, 845 W. Taylor St., Chicago, IL 60617 U.S.A, Fax: (+1) 312-996-0431
| | - Martin Newcomb
- Department of Chemistry, University of Illinois at Chicago, 845 W. Taylor St., Chicago, IL 60617 U.S.A, Fax: (+1) 312-996-0431
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10
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Wei X, Zhang C, Gao X, Gao Y, Yang Y, Guo K, Du X, Pu L, Wang Q. Enhanced Activity and Substrate Specificity by Site-Directed Mutagenesis for the P450 119 Peroxygenase Catalyzed Sulfoxidation of Thioanisole. ChemistryOpen 2019; 8:1076-1083. [PMID: 31406654 PMCID: PMC6682931 DOI: 10.1002/open.201900157] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Indexed: 11/06/2022] Open
Abstract
P450 119 peroxygenase was found to catalyze the sulfoxidation of thioanisole and the sulfonation of sulfoxide in the presence of tert-butyl hydroperoxide (TBHP) for the first time with turnover rates of 1549 min-1 and 196 min-1 respectively. Several mutants were designed to improve the peroxygenation activity and thioanisole specificity by site-directed mutagenesis. The F153G/T213G mutant gave an increase of sulfoxide yield and a decrease of sulfone yield. Moreover the S148P/I161T/K199E/T214V mutant and the K199E mutant with acidic Glu residue contributed to improving the product ratio of sulfoxide to sulfone. Addition of short-alkyl-chain organic acids to the P450 119 peroxygenase-catalyzed sulfur oxidation of thioanisole was investigated. Octanoic acid was found to induce a preferred sulfoxidation of thioanisole catalyzed by the F153G/T213G mutant to give approximately 2.4-fold increase in turnover rate with a k cat value of 3687 min-1 relative to that of the wild-type, and by the F153G mutant to give the R-sulfoxide up to 30 % ee. The experimental control and the proposed mechanism for the P450 119 peroxygenase-catalyzed sulfoxidation of thioanisole in the presence of octanoic acid suggested that octanoic acid could partially occupy the substrate pocket; meanwhile the F153G mutation could enhance the substrate specificity, which could lead to efficiently regulate the spatial orientation of thioanisole and facilitate the formation of Compound I. This is the most effective catalytic system for the P450 119 peroxygenase-catalyzed sulfoxidation of thioanisole.
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Affiliation(s)
- Xiaoyao Wei
- Department of Medicinal Chemistry, School of Pharmacy Southwest Medical University Luzhou Sichuan 646000 P. R. China
| | - Chun Zhang
- Department of Medicinal Chemistry, School of Pharmacy Southwest Medical University Luzhou Sichuan 646000 P. R. China
| | - Xiaowei Gao
- Department of Medicinal Chemistry, School of Pharmacy Southwest Medical University Luzhou Sichuan 646000 P. R. China
| | - Yanping Gao
- Department of Medicinal Chemistry, School of Pharmacy Southwest Medical University Luzhou Sichuan 646000 P. R. China
| | - Ya Yang
- Department of Medicinal Chemistry, School of Pharmacy Southwest Medical University Luzhou Sichuan 646000 P. R. China
| | - Kai Guo
- Department of Medicinal Chemistry, School of Pharmacy Southwest Medical University Luzhou Sichuan 646000 P. R. China
| | - Xi Du
- Department of Medicinal Chemistry, School of Pharmacy Southwest Medical University Luzhou Sichuan 646000 P. R. China
| | - Lin Pu
- Department of Chemistry University of Virginia Charlottesville VA 22904-4319 USA
| | - Qin Wang
- Department of Medicinal Chemistry, School of Pharmacy Southwest Medical University Luzhou Sichuan 646000 P. R. China
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11
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Huang X, Groves JT. Oxygen Activation and Radical Transformations in Heme Proteins and Metalloporphyrins. Chem Rev 2018; 118:2491-2553. [PMID: 29286645 PMCID: PMC5855008 DOI: 10.1021/acs.chemrev.7b00373] [Citation(s) in RCA: 577] [Impact Index Per Article: 96.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Indexed: 12/20/2022]
Abstract
As a result of the adaptation of life to an aerobic environment, nature has evolved a panoply of metalloproteins for oxidative metabolism and protection against reactive oxygen species. Despite the diverse structures and functions of these proteins, they share common mechanistic grounds. An open-shell transition metal like iron or copper is employed to interact with O2 and its derived intermediates such as hydrogen peroxide to afford a variety of metal-oxygen intermediates. These reactive intermediates, including metal-superoxo, -(hydro)peroxo, and high-valent metal-oxo species, are the basis for the various biological functions of O2-utilizing metalloproteins. Collectively, these processes are called oxygen activation. Much of our understanding of the reactivity of these reactive intermediates has come from the study of heme-containing proteins and related metalloporphyrin compounds. These studies not only have deepened our understanding of various functions of heme proteins, such as O2 storage and transport, degradation of reactive oxygen species, redox signaling, and biological oxygenation, etc., but also have driven the development of bioinorganic chemistry and biomimetic catalysis. In this review, we survey the range of O2 activation processes mediated by heme proteins and model compounds with a focus on recent progress in the characterization and reactivity of important iron-oxygen intermediates. Representative reactions initiated by these reactive intermediates as well as some context from prior decades will also be presented. We will discuss the fundamental mechanistic features of these transformations and delineate the underlying structural and electronic factors that contribute to the spectrum of reactivities that has been observed in nature as well as those that have been invented using these paradigms. Given the recent developments in biocatalysis for non-natural chemistries and the renaissance of radical chemistry in organic synthesis, we envision that new enzymatic and synthetic transformations will emerge based on the radical processes mediated by metalloproteins and their synthetic analogs.
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Affiliation(s)
- Xiongyi Huang
- Department
of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
- Department
of Chemistry, California Institute of Technology, Pasadena, California 91125, United States
| | - John T. Groves
- Department
of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
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12
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Wang L, Wei S, Pan X, Liu P, Du X, Zhang C, Pu L, Wang Q. Enhanced Turnover for the P450 119 Peroxygenase-Catalyzed Asymmetric Epoxidation of Styrenes by Random Mutagenesis. Chemistry 2018; 24:2741-2749. [DOI: 10.1002/chem.201705460] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Li Wang
- Center for Pharmaceutical Research and Development, School of Pharmacy; Southwest Medical University, Luzhou; Sichuan 646000 P.R. China
- Department of Medicinal Chemistry, School of Pharmacy; Southwest Medical University, Luzhou; Sichuan 646000 P.R. China
| | - Siping Wei
- Center for Pharmaceutical Research and Development, School of Pharmacy; Southwest Medical University, Luzhou; Sichuan 646000 P.R. China
- Department of Medicinal Chemistry, School of Pharmacy; Southwest Medical University, Luzhou; Sichuan 646000 P.R. China
| | - Xianchao Pan
- Center for Pharmaceutical Research and Development, School of Pharmacy; Southwest Medical University, Luzhou; Sichuan 646000 P.R. China
- Department of Medicinal Chemistry, School of Pharmacy; Southwest Medical University, Luzhou; Sichuan 646000 P.R. China
| | - Pingxian Liu
- Center for Pharmaceutical Research and Development, School of Pharmacy; Southwest Medical University, Luzhou; Sichuan 646000 P.R. China
- Department of Medicinal Chemistry, School of Pharmacy; Southwest Medical University, Luzhou; Sichuan 646000 P.R. China
| | - Xi Du
- Center for Pharmaceutical Research and Development, School of Pharmacy; Southwest Medical University, Luzhou; Sichuan 646000 P.R. China
| | - Chun Zhang
- Center for Pharmaceutical Research and Development, School of Pharmacy; Southwest Medical University, Luzhou; Sichuan 646000 P.R. China
| | - Lin Pu
- Center for Pharmaceutical Research and Development, School of Pharmacy; Southwest Medical University, Luzhou; Sichuan 646000 P.R. China
- Department of Chemistry; University of Virginia; Charlottesville VA 22904-4319 USA
| | - Qin Wang
- Center for Pharmaceutical Research and Development, School of Pharmacy; Southwest Medical University, Luzhou; Sichuan 646000 P.R. China
- Department of Medicinal Chemistry, School of Pharmacy; Southwest Medical University, Luzhou; Sichuan 646000 P.R. China
- Department of Chemistry; University of Virginia; Charlottesville VA 22904-4319 USA
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13
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Morrow WP, Sardar S, Thapa P, Hossain MS, Foss FW, Pierce BS. Thiol dioxygenase turnover yields benzothiazole products from 2-mercaptoaniline and O 2-dependent oxidation of primary alcohols. Arch Biochem Biophys 2017; 631:66-74. [PMID: 28826737 PMCID: PMC5616182 DOI: 10.1016/j.abb.2017.08.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 08/15/2017] [Accepted: 08/16/2017] [Indexed: 10/19/2022]
Abstract
Thiol dioxygenases are non-heme mononuclear iron enzymes that catalyze the O2-dependent oxidation of free thiols (-SH) to produce the corresponding sulfinic acid (-SO2-). Previous chemical rescue studies identified a putative FeIII-O2- intermediate that precedes substrate oxidation in Mus musculus cysteine dioxygenase (Mm CDO). Given that a similar reactive intermediate has been identified in the extradiol dioxygenase 2, 3-HCPD, it is conceivable that these enzymes share other mechanistic features with regard to substrate oxidation. To explore this possibility, enzymatic reactions with Mm CDO (as well as the bacterial 3-mercaptopropionic acid dioxygenase, Av MDO) were performed using a substrate analogue (2-mercaptoaniline, 2ma). This aromatic thiol closely approximates the catecholic substrate of homoprotocatechuate of 2, 3-HPCD while maintaining the 2-carbon thiol-amine separation preferred by Mm CDO. Remarkably, both enzymes exhibit 2ma-gated O2-consumption; however, none of the expected products for thiol dioxygenase or intra/extradiol dioxygenase reactions were observed. Instead, benzothiazoles are produced by the condensation of 2ma with aldehydes formed by an off-pathway oxidation of primary alcohols added to aqueous reactions to solubilize the substrate. The observed oxidation of 1º-alcohols in 2ma-reactions is consistent with the formation of a high-valent intermediate similar to what has been reported for cytochrome P450 and mononuclear iron model complexes.
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Affiliation(s)
- William P Morrow
- Department of Chemistry & Biochemistry, College of Science, The University of Texas at Arlington, Arlington, TX 76019, United States
| | - Sinjinee Sardar
- Department of Chemistry & Biochemistry, College of Science, The University of Texas at Arlington, Arlington, TX 76019, United States
| | - Pawan Thapa
- Department of Chemistry & Biochemistry, College of Science, The University of Texas at Arlington, Arlington, TX 76019, United States
| | - Mohammad S Hossain
- Department of Chemistry & Biochemistry, College of Science, The University of Texas at Arlington, Arlington, TX 76019, United States
| | - Frank W Foss
- Department of Chemistry & Biochemistry, College of Science, The University of Texas at Arlington, Arlington, TX 76019, United States
| | - Brad S Pierce
- Department of Chemistry & Biochemistry, College of Science, The University of Texas at Arlington, Arlington, TX 76019, United States.
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14
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Kupper C, Mondal B, Serrano-Plana J, Klawitter I, Neese F, Costas M, Ye S, Meyer F. Nonclassical Single-State Reactivity of an Oxo-Iron(IV) Complex Confined to Triplet Pathways. J Am Chem Soc 2017; 139:8939-8949. [PMID: 28557448 DOI: 10.1021/jacs.7b03255] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
C-H bond activation mediated by oxo-iron (IV) species represents the key step of many heme and nonheme O2-activating enzymes. Of crucial interest is the effect of spin state of the FeIV(O) unit. Here we report the C-H activation kinetics and corresponding theoretical investigations of an exclusive tetracarbene ligated oxo-iron(IV) complex, [LNHCFeIV(O)(MeCN)]2+ (1). Kinetic traces using substrates with bond dissociation energies (BDEs) up to 80 kcal mol-1 show pseudo-first-order behavior and large but temperature-dependent kinetic isotope effects (KIE 32 at -40 °C). When compared with a topologically related oxo-iron(IV) complex bearing an equatorial N-donor ligand, [LTMCFeIV(O) (MeCN)]2+ (A), the tetracarbene complex 1 is significantly more reactive with second order rate constants k'2 that are 2-3 orders of magnitude higher. UV-vis experiments in tandem with cryospray mass spectrometry evidence that the reaction occurs via formation of a hydroxo-iron(III) complex (4) after the initial H atom transfer (HAT). An extensive computational study using a wave function based multireference approach, viz. complete active space self-consistent field (CASSCF) followed by N-electron valence perturbation theory up to second order (NEVPT2), provided insight into the HAT trajectories of 1 and A. Calculated free energy barriers for 1 reasonably agree with experimental values. Because the strongly donating equatorial tetracarbene pushes the Fe-dx2-y2 orbital above dz2, 1 features a dramatically large quintet-triplet gap of ∼18 kcal/mol compared to ∼2-3 kcal/mol computed for A. Consequently, the HAT process performed by 1 occurs on the triplet surface only, in contrast to complex A reported to feature two-state-reactivity with contributions from both triplet and quintet states. Despite this, the reactive FeIV(O) units in 1 and A undergo the same electronic-structure changes during HAT. Thus, the unique complex 1 represents a pure "triplet-only" ferryl model.
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Affiliation(s)
- Claudia Kupper
- Universität Göttingen , Institut für Anorganische Chemie, Tammannstrasse 4, 37077 Göttingen, Germany
| | - Bhaskar Mondal
- Max-Planck Institut für Chemische Energiekonversion , Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Joan Serrano-Plana
- Institut de Química Computacional i Catàlisi (IQCC), Departament de Quimica, Universitat de Girona , Campus Montilivi, E17071 Girona, Catalonia, Spain
| | - Iris Klawitter
- Universität Göttingen , Institut für Anorganische Chemie, Tammannstrasse 4, 37077 Göttingen, Germany
| | - Frank Neese
- Max-Planck Institut für Chemische Energiekonversion , Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Miquel Costas
- Institut de Química Computacional i Catàlisi (IQCC), Departament de Quimica, Universitat de Girona , Campus Montilivi, E17071 Girona, Catalonia, Spain
| | - Shengfa Ye
- Max-Planck Institut für Chemische Energiekonversion , Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Franc Meyer
- Universität Göttingen , Institut für Anorganische Chemie, Tammannstrasse 4, 37077 Göttingen, Germany
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15
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Lang J, Maréchal A, Couture M, Santolini J. Reaction Intermediates and Molecular Mechanism of Peroxynitrite Activation by NO Synthases. Biophys J 2017; 111:2099-2109. [PMID: 27851935 DOI: 10.1016/j.bpj.2016.05.056] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 05/26/2016] [Accepted: 05/31/2016] [Indexed: 11/26/2022] Open
Abstract
The activation of the peroxynitrite anion (PN) by hemoproteins, which leads to its detoxification or, on the contrary to the enhancement of its cytotoxic activity, is a reaction of physiological importance that is still poorly understood. It has been known for some years that the reaction of hemoproteins, notably cytochrome P450, with PN leads to the buildup of an intermediate species with a Soret band at ∼435 nm (I435). The nature of this intermediate is, however, debated. On the one hand, I435 has been presented as a compound II species that can be photoactivated to compound I. A competing alternative involves the assignment of I435 to a ferric-nitrosyl species. Similar to cytochromes P450, the buildup of I435 occurs in nitric oxide synthases (NOSs) upon their reaction with excess PN. Interestingly, the NOS isoforms vary in their capacity to detoxify/activate PN, although they all show the buildup of I435. To better understand PN activation/detoxification by heme proteins, a definitive assignment of I435 is needed. Here we used a combination of fine kinetic analysis under specific conditions (pH, PN concentrations, and PN/NOSs ratios) to probe the formation of I435. These studies revealed that I435 is not formed upon homolytic cleavage of the O-O bond of PN, but instead arises from side reactions associated with excess PN. Characterization of I435 by resonance Raman spectroscopy allowed its identification as a ferric iron-nitrosyl complex. Our study indicates that the model used so far to depict PN interactions with hemo-thiolate proteins, i.e., leading to the formation and accumulation of compound II, needs to be reconsidered.
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Affiliation(s)
- Jérôme Lang
- Laboratory of Oxidative Stress and Detoxification, iBiTec-S/I2BC, UMR 9198, CEA-Centre National de la Recherche Scientifique Université Paris Sud, CEA Saclay, Gif-sur-Yvette Cedex, France; Department of Biochemistry, Université Laval, Laval, Québec, Canada
| | - Amandine Maréchal
- Laboratory of Oxidative Stress and Detoxification, iBiTec-S/I2BC, UMR 9198, CEA-Centre National de la Recherche Scientifique Université Paris Sud, CEA Saclay, Gif-sur-Yvette Cedex, France
| | - Manon Couture
- Department of Biochemistry, Université Laval, Laval, Québec, Canada
| | - Jérôme Santolini
- Laboratory of Oxidative Stress and Detoxification, iBiTec-S/I2BC, UMR 9198, CEA-Centre National de la Recherche Scientifique Université Paris Sud, CEA Saclay, Gif-sur-Yvette Cedex, France.
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16
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Nasrollahi R, Zakavi S. Evidence on the Nature of the Active Oxidants Involved in the Oxidation of Alcohols with Oxone Catalyzed by an Electron‐Deficient Manganese Porphyrin: A Combined Kinetic and Mechanistic Study. Eur J Inorg Chem 2017. [DOI: 10.1002/ejic.201601488] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Rahele Nasrollahi
- Institute for Advanced Studies in Basic Sciences (IASBS) 45137‐66731 Zanjan Iran
| | - Saeed Zakavi
- Institute for Advanced Studies in Basic Sciences (IASBS) 45137‐66731 Zanjan Iran
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17
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Huang X, Groves JT. Beyond ferryl-mediated hydroxylation: 40 years of the rebound mechanism and C-H activation. J Biol Inorg Chem 2016; 22:185-207. [PMID: 27909920 PMCID: PMC5350257 DOI: 10.1007/s00775-016-1414-3] [Citation(s) in RCA: 195] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 11/03/2016] [Indexed: 11/24/2022]
Abstract
Since our initial report in 1976, the oxygen rebound mechanism has become the consensus mechanistic feature for an expanding variety of enzymatic C-H functionalization reactions and small molecule biomimetic catalysts. For both the biotransformations and models, an initial hydrogen atom abstraction from the substrate (R-H) by high-valent iron-oxo species (Fen=O) generates a substrate radical and a reduced iron hydroxide, [Fen-1-OH ·R]. This caged radical pair then evolves on a complicated energy landscape through a number of reaction pathways, such as oxygen rebound to form R-OH, rebound to a non-oxygen atom affording R-X, electron transfer of the incipient radical to yield a carbocation, R+, desaturation to form olefins, and radical cage escape. These various flavors of the rebound process, often in competition with each other, give rise to the wide range of C-H functionalization reactions performed by iron-containing oxygenases. In this review, we first recount the history of radical rebound mechanisms, their general features, and key intermediates involved. We will discuss in detail the factors that affect the behavior of the initial caged radical pair and the lifetimes of the incipient substrate radicals. Several representative examples of enzymatic C-H transformations are selected to illustrate how the behaviors of the radical pair [Fen-1-OH ·R] determine the eventual reaction outcome. Finally, we discuss the powerful potential of "radical rebound" processes as a general paradigm for developing novel C-H functionalization reactions with synthetic, biomimetic catalysts. We envision that new chemistry will continue to arise by bridging enzymatic "radical rebound" with synthetic organic chemistry.
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18
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Zhang C, Liu PX, Huang LY, Wei SP, Wang L, Yang SY, Yu XQ, Pu L, Wang Q. Engineering P450 Peroxygenase to Catalyze Highly Enantioselective Epoxidation of cis
-β-Methylstyrenes. Chemistry 2016; 22:10969-75. [PMID: 27362319 DOI: 10.1002/chem.201601176] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 04/25/2016] [Indexed: 02/05/2023]
Affiliation(s)
- Chun Zhang
- Department of Medicinal Chemistry; Southwest Medical University; No. 319, Zhongshan Road Luzhou Sichuan 646000 P. R. China
| | - Ping-Xian Liu
- Department of Medicinal Chemistry; Southwest Medical University; No. 319, Zhongshan Road Luzhou Sichuan 646000 P. R. China
| | - Lu-Yi Huang
- State Key Laboratory of Biotherapy; West China Hospital; Sichuan University; No.17 People's South Road Chengdu Sichuan 610041 P. R. China
| | - Si-Ping Wei
- Department of Medicinal Chemistry; Southwest Medical University; No. 319, Zhongshan Road Luzhou Sichuan 646000 P. R. China
| | - Li Wang
- Department of Medicinal Chemistry; Southwest Medical University; No. 319, Zhongshan Road Luzhou Sichuan 646000 P. R. China
| | - Sheng-Yong Yang
- State Key Laboratory of Biotherapy; West China Hospital; Sichuan University; No.17 People's South Road Chengdu Sichuan 610041 P. R. China
| | - Xiao-Qi Yu
- College of Chemistry; Sichuan University; No. 29 Wangjiang Road Chengdu Sichuan 610064 P. R. China
| | - Lin Pu
- Department of Medicinal Chemistry; Southwest Medical University; No. 319, Zhongshan Road Luzhou Sichuan 646000 P. R. China
- Department of Chemistry; University of Virginia; Charlottesville Virginia 22903 USA
| | - Qin Wang
- Department of Medicinal Chemistry; Southwest Medical University; No. 319, Zhongshan Road Luzhou Sichuan 646000 P. R. China
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19
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Wang L, Shang S, Li G, Ren L, Lv Y, Gao S. Iron/ABNO-Catalyzed Aerobic Oxidation of Alcohols to Aldehydes and Ketones under Ambient Atmosphere. J Org Chem 2016; 81:2189-93. [DOI: 10.1021/acs.joc.6b00009] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lianyue Wang
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy, Dalian 116023, China
| | - SenSen Shang
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy, Dalian 116023, China
- Graduate School of the Chinese Academy of Sciences, Beijing 100049, China
| | - Guosong Li
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy, Dalian 116023, China
| | - Lanhui Ren
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy, Dalian 116023, China
- Graduate School of the Chinese Academy of Sciences, Beijing 100049, China
| | - Ying Lv
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy, Dalian 116023, China
| | - Shuang Gao
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy, Dalian 116023, China
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20
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Chatterjee B, Gunanathan C. Ruthenium Catalyzed Selective α- and α,β-Deuteration of Alcohols Using D2O. Org Lett 2016; 17:4794-7. [PMID: 26381108 DOI: 10.1021/acs.orglett.5b02254] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Highly selective ruthenium catalyzed α-deuteration of primary alcohols and α,β-deuteration of secondary alcohols are achieved using deuterium oxide (D2O) as a source of deuterium and reaction solvent. Minimal loading of catalyst (Ru-macho), base (KO(t)Bu), and low temperature heating provided efficient selective deuteration of alcohols making the process practically attractive and environmentally benign. Mechanistic studies indicate the D-O(D/R) bond activations by metal-ligand cooperation and intermediacy of carbonyl compounds resulting from dehydrogenation of alcohols.
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Affiliation(s)
- Basujit Chatterjee
- School of Chemical Sciences, National Institute of Science Education and Research (NISER) , Bhubaneswar-751 005, India
| | - Chidambaram Gunanathan
- School of Chemical Sciences, National Institute of Science Education and Research (NISER) , Bhubaneswar-751 005, India
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21
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Ghosh M, Nikhil YLK, Dhar BB, Sen Gupta S. Mechanism of Alcohol Oxidation by Fe(V)(O) at Room Temperature. Inorg Chem 2015; 54:11792-8. [PMID: 26645088 DOI: 10.1021/acs.inorgchem.5b01937] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Selective oxidation of alcohol to its corresponding carbonyl compound is an important chemical process in biological as well as industrial reactions. The heme containing enzyme CytP450 has been known to selectively oxidize alcohols to their corresponding carbonyl compounds. The mechanism of this reaction, which involves high-valent Fe(IV)(O)-porphyrin(•+) intermediate with alcohol, has been well-studied extensively both with the native enzyme and with model complexes. In this paper, we report for the first time the mechanistic insight of alcohol oxidation with Fe(V)(O) complex of biuret TAML (bTAML), which is isoelectronic with Fe(IV)(O)-porphyrin(•+) intermediate form in CytP450. The oxidations displayed saturation kinetics, which allowed us to determine both the binding constants and first-order rate constants for the reaction. The K and k values observed for the oxidation of benzyl alcohol by Fe(V)(O) at room temperature (K = 300 M(-1), k = 0.35 s(-1)) is very similar to that obtained by CytP450 compound I at -50 °C (K = 214 M(-1), k = 0.48 s(-1)). Thermodynamic parameters determined from van't Hoff's plot (ΔH∼ -4 kcal/mol) suggest hydrogen bonding interaction between substrate and bTAML ligand framework of the Fe(V)(O) complex. Analysis of H/D KIE (kH/kD ∼ 19 at 303 K), Hammett correlation and linearity in Bell-Evans-Polyanski plot points to the C-H abstraction as the rate determination step. Finally, experiments using Fe(V)(O(18)) for benzyl alcohol oxidation and use of the "radical clock" cyclobutanol as a substrate shows the absence of a rebound mechanism as is observed for CytP450. Instead, an ET/PT process is proposed after C-H abstraction leading to formation of the aldehyde, similar to what has been proposed for the heme and nonheme model compounds.
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Affiliation(s)
- Munmun Ghosh
- Chemical Engineering Division, CSIR-National Chemical Laboratory , Pune 411008, India
| | - Y L K Nikhil
- Chemical Engineering Division, CSIR-National Chemical Laboratory , Pune 411008, India
| | - Basab B Dhar
- Department of Chemistry, Shiv Nadar University , Goutam Buddha Nagar, UP 201314, India
| | - Sayam Sen Gupta
- Chemical Engineering Division, CSIR-National Chemical Laboratory , Pune 411008, India
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22
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Viciano I, Castillo R, Martí S. QM/MM modeling of the hydroxylation of the androstenedione substrate catalyzed by cytochrome P450 aromatase (CYP19A1). J Comput Chem 2015; 36:1736-47. [DOI: 10.1002/jcc.23967] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 04/07/2015] [Accepted: 05/16/2015] [Indexed: 01/30/2023]
Affiliation(s)
- Ignacio Viciano
- Departament de Química Física i Analítica; Universitat Jaume I; Castelló 12071 Spain
| | - Raquel Castillo
- Departament de Química Física i Analítica; Universitat Jaume I; Castelló 12071 Spain
| | - Sergio Martí
- Departament de Química Física i Analítica; Universitat Jaume I; Castelló 12071 Spain
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23
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Zhang C, Li J, Yang B, He F, Yang SY, Yu XQ, Wang Q. Enhanced turnover rate and enantioselectivity in the asymmetric epoxidation of styrene by new T213G mutants of CYP 119. RSC Adv 2014. [DOI: 10.1039/c4ra04626a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
New CYP 119 T213G mutants were constructed and characterized. Introduction of T213G mutation into the wild-type CYP 119 enhances the turnover rate for the styrene epoxidation to 346.2 min−1, and the double T213G/T214V mutant improves the ratio of the S- and R-enantiomers of the epoxide products to 5.8. The molecular docking results support our initial design and experimental data.
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Affiliation(s)
- Chun Zhang
- Department of Medicinal Chemistry
- Luzhou Medical College
- Luzhou 646000, China
| | - Jing Li
- Department of Medicinal Chemistry
- Luzhou Medical College
- Luzhou 646000, China
| | - Bo Yang
- State Key Laboratory of Biotherapy
- West China Hospital
- Sichuan University
- Chengdu 610041, China
| | - Fang He
- Department of Medicinal Chemistry
- Luzhou Medical College
- Luzhou 646000, China
| | - Sheng-Yong Yang
- State Key Laboratory of Biotherapy
- West China Hospital
- Sichuan University
- Chengdu 610041, China
| | - Xiao-Qi Yu
- College of Chemistry
- Sichuan University
- Chengdu 610064, China
| | - Qin Wang
- Department of Medicinal Chemistry
- Luzhou Medical College
- Luzhou 646000, China
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24
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Krest CM, Onderko EL, Yosca TH, Calixto JC, Karp RF, Livada J, Rittle J, Green MT. Reactive intermediates in cytochrome p450 catalysis. J Biol Chem 2013; 288:17074-81. [PMID: 23632017 DOI: 10.1074/jbc.r113.473108] [Citation(s) in RCA: 142] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Recently, we reported the spectroscopic and kinetic characterizations of cytochrome P450 compound I in CYP119A1, effectively closing the catalytic cycle of cytochrome P450-mediated hydroxylations. In this minireview, we focus on the developments that made this breakthrough possible. We examine the importance of enzyme purification in the quest for reactive intermediates and report the preparation of compound I in a second P450 (P450ST). In an effort to bring clarity to the field, we also examine the validity of controversial reports claiming the production of P450 compound I through the use of peroxynitrite and laser flash photolysis.
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Affiliation(s)
- Courtney M Krest
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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25
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Khaskin E, Milstein D. Simple and Efficient Catalytic Reaction for the Selective Deuteration of Alcohols. ACS Catal 2013. [DOI: 10.1021/cs400092p] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Eugene Khaskin
- Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, Israel
| | - David Milstein
- Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, Israel
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26
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Isobe H, Yamaguchi K, Okumura M, Shimada J. Role of Perferryl–Oxo Oxidant in Alkane Hydroxylation Catalyzed by Cytochrome P450: A Hybrid Density Functional Study. J Phys Chem B 2012; 116:4713-30. [DOI: 10.1021/jp211184y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hiroshi Isobe
- Department of Chemistry, Graduate
School of Science, Osaka University, Toyonaka,
Osaka 560-0043, Japan
| | - Kizashi Yamaguchi
- Department of Chemistry, Graduate
School of Science, Osaka University, Toyonaka,
Osaka 560-0043, Japan
| | - Mitsutaka Okumura
- Department of Chemistry, Graduate
School of Science, Osaka University, Toyonaka,
Osaka 560-0043, Japan
| | - Jiro Shimada
- Green
Innovation Research Laboratories, NEC Corporation, 34, Miyukigaoka, Tsukuba, Ibaraki
305-8501, Japan
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27
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Su Z, Chen X, Horner JH, Newcomb M. Rate-Controlling Isomerizations in Fatty Acid Oxidations by a Cytochrome P450 Compound I. Chemistry 2012; 18:2472-6. [DOI: 10.1002/chem.201103170] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Revised: 12/14/2011] [Indexed: 11/11/2022]
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28
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Zhou M, Balcells D, Parent AR, Crabtree RH, Eisenstein O. Cp* Iridium Precatalysts for Selective C–H Oxidation via Direct Oxygen Insertion: A Joint Experimental/Computational Study. ACS Catal 2012. [DOI: 10.1021/cs2005899] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Meng Zhou
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut
06520, United States
| | - David Balcells
- Department
of Chemistry, Universitat Autònoma de Barcelona, 08193 Bellaterra,
Barcelona, Catalonia, Spain
| | - Alexander R. Parent
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut
06520, United States
| | - Robert H. Crabtree
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut
06520, United States
| | - Odile Eisenstein
- Institut Charles Gerhardt, Université Montpellier 2, CNRS 5253, cc 15001,
Place Eugène Bataillon 34095, Montpellier, France
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29
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30
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Esteruelas MA, Garcı́a-Obregón T, Herrero J, Oliván M. Osmium-Catalyzed Oxidation of Primary Alcohols with Molecular Oxygen. Organometallics 2011. [DOI: 10.1021/om200684m] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Miguel A. Esteruelas
- Departamento de Quı́mica
Inorgánica-Instituto de Sı́ntesis
Quı́mica y Catálisis Homogénea (ISQCH), Universidad de Zaragoza-CSIC, 50009
Zaragoza, Spain
| | - Tania Garcı́a-Obregón
- Departamento de Ingenierı́a Quı́mica
y Quı́mica
Inorgánica, Universidad de Cantabria, 39005 Santander, Spain
| | - Juana Herrero
- Departamento de Ingenierı́a Quı́mica
y Quı́mica
Inorgánica, Universidad de Cantabria, 39005 Santander, Spain
| | - Montserrat Oliván
- Departamento de Quı́mica
Inorgánica-Instituto de Sı́ntesis
Quı́mica y Catálisis Homogénea (ISQCH), Universidad de Zaragoza-CSIC, 50009
Zaragoza, Spain
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31
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Chen X, Su Z, Horner JH, Newcomb M. Oxidation of 10-undecenoic acid by cytochrome P450(BM-3) and its Compound I transient. Org Biomol Chem 2011; 9:7427-33. [PMID: 21901220 DOI: 10.1039/c1ob06035j] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Oxidations of 10-undecenoic acid by cytochrome P450(BM-3) and its Compound I transient were studied. The only product formed in Compound I oxidations was 10,11-epoxyundecanoic acid, whereas the enzyme under turnover conditions gave the epoxide and 9-hydroxy-10-undecenoic acid in a 10 : 90 ratio. Kinetic studies at 0 °C of oxidations by Compounds I formed by MCPBA oxidation and by a photo-oxidation pathway gave the same results, displaying saturation kinetics that yielded equilibrium binding constants and first-order oxidation rate constants that were experimentally indistinguishable. Oxidation of 10-undecenoic acid by Compound I from CYP119 generated by MCBPA oxidation also gave 10,11-epoxyundecanoic acid as the only product. CYP119 Compound I bound the substrate less strongly but reacted with a faster oxidation rate constant than P450(BM-3) Compound I. The kinetic parameters for oxidation of the substrate by P450(BM-3) under turnover conditions were similar to those of the Compound I transient even though the products differed.
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Affiliation(s)
- Xiaohong Chen
- Department of Chemistry, University of Illinois at Chicago, 845 W. Taylor St., Chicago, IL 60607, USA.
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32
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Isobe H, Yamanaka S, Okumura M, Yamaguchi K, Shimada J. Unique Structural and Electronic Features of Perferryl–Oxo Oxidant in Cytochrome P450. J Phys Chem B 2011; 115:10730-8. [DOI: 10.1021/jp206004y] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hiroshi Isobe
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Syusuke Yamanaka
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Mitsutaka Okumura
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Kizashi Yamaguchi
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Jiro Shimada
- Green Innovation Research Laboratories, NEC Corporation, 34, Miyukigaoka, Tsukuba, Ibaraki 305-8501, Japan
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Chen H, Lai W, Shaik S. Multireference and multiconfiguration ab initio methods in heme-related systems: what have we learned so far? J Phys Chem B 2011; 115:1727-42. [PMID: 21344948 DOI: 10.1021/jp110016u] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
This work reviews the recent applications of ab initio multireference/multiconfiguration (MR/MC) electronic structure methods to heme-related systems, involving tetra-, penta-, and hexa-coordinate species, as well as the high-valent iron-oxo species. The current accuracy of these methods in the various systems is discussed, with special attention to potential sources of systematic errors. Thus, the review summarizes and tries to rationalize the key elements of MR/MC calculations, namely, the choice of the employed active space, especially the so-called double-shell effect that has already been recognized to be important in transition-metal-containing systems, and the impact of these elements on the spin-state energetics of heme species, as well as on the bonding mechanism of small molecules to the heme. It is shown that expansion of the MC wave function into one based on localized orbitals provides a compact and insightful view on some otherwise complex electronic structures. The effects of protein environment on the MR/MC results are summarized for the few available quantum mechanical/molecular mechanical (QM/MM) studies. Comparisons with corresponding DFT results are also made wherever available. Potential future directions are proposed.
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Affiliation(s)
- Hui Chen
- Institute of Chemistry, Hebrew University of Jerusalem, Givat Ram Campus, 91904 Jerusalem, Israel.
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34
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Radoń M, Broclawik E, Pierloot K. DFT and Ab Initio Study of Iron-Oxo Porphyrins: May They Have a Low-Lying Iron(V)-Oxo Electromer? J Chem Theory Comput 2011; 7:898-908. [DOI: 10.1021/ct1006168] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Mariusz Radoń
- Faculty of Chemistry, Jagiellonian University, ul. Ingardena 3, 30-060 Kraków, Poland
| | - Ewa Broclawik
- Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, ul. Niezapominajek 8, 30-239 Kraków, Poland
| | - Kristine Pierloot
- Department of Chemistry, University of Leuven, Celestijnenlaan 200F, B-3001 Heverlee-Leuven, Belgium
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35
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Cooper HLR, Groves JT. Molecular probes of the mechanism of cytochrome P450. Oxygen traps a substrate radical intermediate. Arch Biochem Biophys 2011; 507:111-8. [PMID: 21075070 PMCID: PMC3041850 DOI: 10.1016/j.abb.2010.11.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Revised: 11/05/2010] [Accepted: 11/05/2010] [Indexed: 01/05/2023]
Abstract
The diagnostic substrate tetramethylcyclopropane (TMCP) has been reexamined as a substrate with three drug- and xenobiotic-metabolizing cytochrome P450 enzymes, human CYP2E1, CYP3A4 and rat CYP2B1. The major hydroxylation product in all cases was the unrearranged primary alcohol along with smaller amounts of a rearranged tertiary alcohol. Significantly, another ring-opened product, diacetone alcohol, was also observed. With CYP2E1 this product accounted for 20% of the total turnover. Diacetone alcohol also was detected as a product from TMCP with a biomimetic model catalyst, FeTMPyP, but not with a ruthenium porphyrin catalyst. Lifetimes of the intermediate radicals were determined from the ratios of rearranged and unrearranged products to be 120, 13 and 1ps for CYP2E1, CYP3A4 and CYP2B1, respectively, corresponding to rebound rates of 0.9×10(10)s(-1), 7.2×10(10)s(-1) and 1.0×10(12)s(-1). For the model iron porphyrin, FeTMPyP, a radical lifetime of 81ps and a rebound rate of 1.2×10(10)s(-1) were determined. These apparent radical lifetimes are consistent with earlier reports with a variety of CYP enzymes and radical clock substrates, however, the large amounts of diacetone alcohol with CYP2E1 and the iron porphyrin suggest that for these systems a considerable amount of the intermediate carbon radical is trapped by molecular oxygen. These results add to the view that cage escape of the intermediate carbon radical in [Fe(IV)-OH ()R] can compete with cage collapse to form a C-O bond. The results could be significant with regard to our understanding of iron-catalyzed C-H hydroxylation, the observation of P450-dependent peroxidation and the development of oxidative stress, especially for CYP2E1.
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Affiliation(s)
| | - John T. Groves
- Department of Chemistry, Princeton University, Princeton NJ 08544 USA
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36
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Jung C. The mystery of cytochrome P450 Compound I. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2011; 1814:46-57. [DOI: 10.1016/j.bbapap.2010.06.007] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2010] [Revised: 05/31/2010] [Accepted: 06/04/2010] [Indexed: 10/19/2022]
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Rittle J, Green MT. Cytochrome P450 compound I: capture, characterization, and C-H bond activation kinetics. Science 2010; 330:933-7. [PMID: 21071661 DOI: 10.1126/science.1193478] [Citation(s) in RCA: 986] [Impact Index Per Article: 70.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Cytochrome P450 enzymes are responsible for the phase I metabolism of approximately 75% of known pharmaceuticals. P450s perform this and other important biological functions through the controlled activation of C-H bonds. Here, we report the spectroscopic and kinetic characterization of the long-sought principal intermediate involved in this process, P450 compound I (P450-I), which we prepared in approximately 75% yield by reacting ferric CYP119 with m-chloroperbenzoic acid. The Mössbauer spectrum of CYP119-I is similar to that of chloroperoxidase compound I, although its electron paramagnetic resonance spectrum reflects an increase in |J|/D, the ratio of the exchange coupling to the zero-field splitting. CYP119-I hydroxylates the unactivated C-H bonds of lauric acid [D(C-H) ~ 100 kilocalories per mole], with an apparent second-order rate constant of k(app) = 1.1 × 10(7) per molar per second at 4°C. Direct measurements put a lower limit of k ≥ 210 per second on the rate constant for bound substrate oxidation, whereas analyses involving kinetic isotope effects predict a value in excess of 1400 per second.
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Affiliation(s)
- Jonathan Rittle
- Department of Chemistry, Pennsylvania State University, University Park, PA 16802, USA
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38
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Bach RD. The rate-limiting step in P450 hydroxylation of hydrocarbons a direct comparison of the "somersault" versus the "consensus" mechanism involving compound I. J Phys Chem A 2010; 114:9319-32. [PMID: 20690650 DOI: 10.1021/jp1045518] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Model theoretical quantum mechanical (QM) calculations are described for the P-450 hydroxylation of methane, isobutane, and camphor that compare the concerted somersault H-abstraction mechanism with the oxidation step involving Cpd I. Special emphasis has been placed on maintaining a balanced basis set in the oxidation step. QM calculations, employing the 6-311+G(d,p) basis set on the Fe atom and all of the key surrounding atoms involved in the C-H abstraction step, reaffirm a mechanism involving rearrangement of the iron hydroperoxide group (FeO-OH --> FeO...HO(*)) in concert with hydrogen abstraction from the C-H bond of the substrate by the incipient bound hydroxyl radical HO(*). The barrier for the somersault rearrangement of model Cpd 0 (FeO-OH) is calculated to be 21.4 kcal/mol in the absence of substrate. The overall activation energy for the oxidation of camphor involving the somersault motion of the FeO-OH group of P450 model porphyrin iron(III) hydroperoxide [Por(SH)Fe(III)-OOH(-)] --> [Por(SH)Fe(III)-O....HO(-)] in concert with hydrogen abstraction is DeltaE(++) = 12.4 kcal/mol. The corresponding abstraction of the hydrogen atom from the C-H bond of camphor by Cpd I has an activation barrier of 17.6 kcal/mol. Arguments are presented that the somersault rearrangement is induced by steric compression at the active site. Kinetic isotope effect data are discussed that provides compelling evidence for a rate-limiting step involving C-H bond cleavage.
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Affiliation(s)
- Robert D Bach
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA.
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39
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Roberts KM, Jones JP. Anilinic N-oxides support cytochrome P450-mediated N-dealkylation through hydrogen-atom transfer. Chemistry 2010; 16:8096-107. [PMID: 20521282 DOI: 10.1002/chem.201000185] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The mechanism of N-dealkylation mediated by cytochrome P450 (P450) has long been studied and argued as either a single electron transfer (SET) or a hydrogen atom transfer (HAT) from the amine to the oxidant of the P450, the reputed iron-oxene. In our study, tertiary anilinic N-oxides were used as oxygen surrogates to directly generate a P450-mediated oxidant that is capable of N-dealkylating the dimethylaniline derived from oxygen donation. These surrogates were employed to probe the generated reactive oxygen species and the subsequent mechanism of N-dealkylation to distinguish between the HAT and SET mechanisms. In addition to the expected N-demethylation of the product aniline, 2,3,4,5,6-pentafluoro-N,N-dimethylaniline N-oxide (PFDMAO) was found to be capable of N-dealkylating both N,N-dimethylaniline (DMA) and N-cyclopropyl-N-methylaniline (CPMA). Rate comparisons of the N-demethylation of DMA supported by PFDMAO show a 27-fold faster rate than when supported by N,N-dimethylaniline N-oxide (DMAO). Whereas intermolecular kinetic isotope effects were masked, intramolecular measurements showed values reflective of those seen previously in DMAO- and the native NADPH/O(2)-supported systems (2.33 and 2.8 for the N-demethylation of PFDMA and DMA from the PFDMAO system, respectively). PFDMAO-supported N-dealkylation of CPMA led to the ring-intact product N-cyclopropylaniline (CPA), similar to that seen with the native system. The formation of CPA argues against a SET mechanism in favor of a P450-like HAT mechanism. We suggest that the similarity of KIEs, in addition to the formation of the ring-intact CPA, argues for a similar mechanism of Compound I (Cpd I) formation followed by HAT for N-dealkylation by the native and N-oxide-supported systems and demonstrate the ability of the N-oxide-generated oxidant to act as an accurate mimic of the native P450 oxidant.
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Affiliation(s)
- Kenneth M Roberts
- Department of Chemistry, Washington State University, PO BOX 644630, Pullman, WA 99164-4630, USA
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40
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Abstract
Oxygenated heme proteins are known to react rapidly with nitric oxide (NO) to produce peroxynitrite (PN) at the heme site. This process could lead either to attenuation of the effects of NO or to nitrosative protein damage. PN is a powerful nitrating and oxidizing agent that has been implicated in a variety of cell injuries. Accordingly, it is important to delineate the nature and variety of reaction mechanisms of PN interactions with heme proteins. In this Forum, we survey the range of reactions of PN with heme proteins, with particular attention to myoglobin and cytochrome c. While these two proteins are textbook paradigms for oxygen binding and electron transfer, respectively, both have recently been shown to have other important functions that involve NO and PN. We have recently described direct evidence that ferrylmyolgobin (ferrylMb) and nitrogen dioxide (NO(2)) are both produced during the reaction of PN and metmyolgobin (metMb) (Su, J.; Groves, J. T. J. Am. Chem. Soc. 2009, 131, 12979-12988). Kinetic evidence indicates that these products evolve from the initial formation of a caged radical intermediate [Fe(IV) horizontal lineO.NO(2)]. This caged pair reacts mainly via internal return with a rate constant k(r) to form metMb and nitrate in an oxygen-rebound scenario. Detectable amounts of ferrylMb are observed by stopped-flow spectrophotometry, appearing at a rate consistent with the rate, k(obs), of heme-mediated PN decomposition. Freely diffusing NO(2), which is liberated concomitantly from the radical pair (k(e)), preferentially nitrates myoglobin Tyr103 and added fluorescein. For cytochrome c, Raman spectroscopy has revealed that a substantial fraction of cytochrome c converts to a beta-sheet structure, at the expense of turns and helices at low pH (Balakrishnan, G.; Hu, Y.; Oyerinde, O. F.; Su, J.; Groves, J. T.; Spiro, T. G. J. Am. Chem. Soc., 2007, 129, 504-505). It is proposed that a short beta-sheet segment, comprising residues 37-39 and 58-61, extends itself into the large 37-61 loop when the latter is destabilized by protonation of H26, which forms an anchoring hydrogen bond to loop residue P44. This conformation change ruptures the Met80-Fe bond, as revealed by changes in ligation-sensitive Raman bands. It also induces peroxidase activity with the same temperature profile. This process is suggested to model the apoptotic peroxidation of cardiolipin by cytochrome c.
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Affiliation(s)
- Jia Su
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA
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41
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Abstract
High-valent iron-oxo species are thought to be intermediates in the catalytic cycles of oxygenases and peroxidases. An attractive route to these iron-oxo intermediates involves laser flash-quench oxidation of ferric hemes, as demonstrated by our work on the ferryl (compound II) and ferryl porphyrin radical cation (compound I) intermediates of horseradish peroxidase. Extension of this work to include cytochrome P450-BM3 (CYP102A1) has required covalent attachment of a Ru(II) photosensitizer to a nonnative cysteine near the heme (RuIIK97C-FeIIIP450), in order to promote electron transfer from the Fe(III) porphyrin to photogenerated Ru(III). The conjugate was structurally characterized by X-ray crystallography (2.4 Å resolution; Ru-Fe distance, 24 Å). Flash-quench oxidation of the ferric-aquo heme produces an Fe(IV)-hydroxide species (compound II) within 2 ms. Difference spectra for three singly oxidized P450-BM3 intermediates were obtained from kinetics modeling of the transient absorption data in combination with generalized singular value decomposition analysis and multiexponential fitting.
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42
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Yuan X, Sheng X, Horner JH, Bennett B, Fung LWM, Newcomb M. Low temperature photo-oxidation of chloroperoxidase Compound II. J Inorg Biochem 2010; 104:1156-63. [PMID: 20674981 DOI: 10.1016/j.jinorgbio.2010.07.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2009] [Revised: 07/08/2010] [Accepted: 07/09/2010] [Indexed: 10/19/2022]
Abstract
Oxidation of the heme-thiolate enzyme chloroperoxidase (CPO) from Caldariomyces fumago with peroxynitrite (PN) gave the Compound II intermediate, which was photo-oxidized with 365 nm light to give a reactive oxidizing species. Cryo-solvents at pH ≈ 6 were employed, and reactions were conducted at temperatures as low as -50° C. The activity of CPO as evaluated by the chlorodimedone assay was unaltered by treatment with PN or by production of the oxidizing transient and subsequent reaction with styrene. EPR spectra at 77K gave the amount of ferric protein at each stage in the reaction sequence. The PN oxidation step gave a 6:1 mixture of Compound II and ferric CPO, the photolysis step gave an approximate 1:1 mixture of active oxidant and ferric CPO, and the final mixture after reaction with excess styrene contained ferric CPO in 80% yield. In single turnover reactions at -50°C, styrene was oxidized to styrene oxide in high yield. Kinetic studies of styrene oxidation at -50°C displayed saturation kinetics with an equilibrium constant for formation of the complex of K(bind)=3.8 x 10(4)M(-1) and an oxidation rate constant of k(ox)=0.30s(-1). UV-Visible spectra of mixtures formed in the photo-oxidation sequence at ca. -50° C did not contain the signature Q-band absorbance at 690 nm ascribed to CPO Compound I prepared by chemical oxidation of the enzyme, indicating that different species were formed in the chemical oxidation and the photo-oxidation sequence.
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Affiliation(s)
- Xinting Yuan
- Department of Chemistry, University of Illinois at Chicago, 845 West Taylor St, Chicago, Illinois 60607, USA
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43
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Crestoni ME, Fornarini S, Lanucara F, Warren JJ, Mayer JM. Probing 'spin-forbidden' oxygen-atom transfer: gas-phase reactions of chromium-porphyrin complexes. J Am Chem Soc 2010; 132:4336-43. [PMID: 20218631 DOI: 10.1021/ja9103638] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Oxygen-atom transfer reactions of metalloporphyrin species play an important role in biochemical and synthetic oxidation reactions. An emerging theme in this chemistry is that spin-state changes can play important roles, and a 'two-state' reactivity model has been extensively applied especially in iron porphyrin systems. Herein we explore the gas-phase oxygen-atom transfer chemistry of meso-tetrakis(pentafluorophenyl)porphyrin (TPFPP) chromium complexes, as well as some other tetradentate macrocyclic ligands. Electrospray ionization in concert with Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry has been used to characterize and observe reactivity of the ionic species [(TPFPP)Cr(III)](+) (1) and [(TPFPP)Cr(V)O](+) (2). These are attractive systems to examine the effects of spin-state change on oxygen-atom transfer because the d(1) Cr(V) species are doublets, while the Cr(III) complexes have quartet ground states with high-lying doublet excited states. In the gas phase, [(TPFPP)Cr(III)](+) forms adducts with a variety of neutral donors, but O-atom transfer is only observed for NO(2). Pyridine N-oxide adducts of 1 do yield 2 upon collision-induced dissociation (CID), but the ethylene oxide, DMSO, and TEMPO analogues do not. [(TPFPP)Cr(V)O](+) is shown by its reactivity and by CID experiments to be a terminal metal-oxo with a single, vacant coordination site. It also displays limited reaction chemistry, being deoxygenated only by the very potent reductant P(OMe)(3). In general, [(TPFPP)Cr(V)O](+) species are much less reactive than the Fe and Mn analogues. Thermochemical analysis of the reactions points toward the involvement of spin issues in the lower observed reactivity of the chromium complexes.
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Affiliation(s)
- Maria Elisa Crestoni
- Dipartimento di Studi di Chimica e Tecnologia delle Sostanze Biologicamente Attive, Università di Roma La Sapienza, P.le A. Moro 5, I-00185 Roma, Italy.
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44
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Ouchi A, Nagaoka SI, Mukai K. Tunneling Effect in Regeneration Reaction of Vitamin E by Ubiquinol. J Phys Chem B 2010; 114:6601-7. [DOI: 10.1021/jp910856m] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Aya Ouchi
- Department of Chemistry, Faculty of Science, Ehime University, Matsuyama 790-8577, Japan
| | - Shin-ichi Nagaoka
- Department of Chemistry, Faculty of Science, Ehime University, Matsuyama 790-8577, Japan
| | - Kazuo Mukai
- Department of Chemistry, Faculty of Science, Ehime University, Matsuyama 790-8577, Japan
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45
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Rittle J, Younker JM, Green MT. Cytochrome P450: The Active Oxidant and Its Spectrum. Inorg Chem 2010; 49:3610-7. [DOI: 10.1021/ic902062d] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jonathan Rittle
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Jarod M. Younker
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Michael T. Green
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
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46
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Chowdhury G, Calcutt MW, Guengerich FP. Oxidation of N-Nitrosoalkylamines by human cytochrome P450 2A6: sequential oxidation to aldehydes and carboxylic acids and analysis of reaction steps. J Biol Chem 2010; 285:8031-44. [PMID: 20061389 PMCID: PMC2832954 DOI: 10.1074/jbc.m109.088039] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2009] [Revised: 12/26/2009] [Indexed: 11/06/2022] Open
Abstract
Cytochrome P450 (P450) 2A6 activates nitrosamines, including N,N-dimethylnitrosamine (DMN) and N,N-diethylnitrosamine (DEN), to alkyl diazohydroxides (which are DNA-alkylating agents) and also aldehydes (HCHO from DMN and CH(3)CHO from DEN). The N-dealkylation of DMN had a high intrinsic kinetic deuterium isotope effect ((D)k(app) approximately 10), which was highly expressed in a variety of competitive and non-competitive experiments. The (D)k(app) for DEN was approximately 3 and not expressed in non-competitive experiments. DMN and DEN were also oxidized to HCO(2)H and CH(3)CO(2)H, respectively. In neither case was a lag observed, which was unexpected considering the k(cat) and K(m) parameters measured for oxidation of DMN and DEN to the aldehydes and for oxidation of the aldehydes to the carboxylic acids. Spectral analysis did not indicate strong affinity of the aldehydes for P450 2A6, but pulse-chase experiments showed only limited exchange with added (unlabeled) aldehydes in the oxidations of DMN and DEN to carboxylic acids. Substoichiometric kinetic bursts were observed in the pre-steady-state oxidations of DMN and DEN to aldehydes. A minimal kinetic model was developed that was consistent with all of the observed phenomena and involves a conformational change of P450 2A6 following substrate binding, equilibrium of the P450-substrate complex with a non-productive form, and oxidation of the aldehydes to carboxylic acids in a process that avoids relaxation of the conformation following the first oxidation (i.e. of DMN or DEN to an aldehyde).
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Affiliation(s)
- Goutam Chowdhury
- From the Department of Biochemistry and Center in Molecular Toxicology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146
| | - M. Wade Calcutt
- From the Department of Biochemistry and Center in Molecular Toxicology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146
| | - F. Peter Guengerich
- From the Department of Biochemistry and Center in Molecular Toxicology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146
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47
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Chen H, Song J, Lai W, Wu W, Shaik S. Multiple Low-Lying States for Compound I of P450cam and Chloroperoxidase Revealed from Multireference Ab Initio QM/MM Calculations. J Chem Theory Comput 2010; 6:940-53. [DOI: 10.1021/ct9006234] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hui Chen
- Institute of Chemistry and the Lise Meitner-Minerva Center for Computational Quantum Chemistry, Hebrew University of Jerusalem, Givat Ram Campus, 91904 Jerusalem, Israel, State Key Laboratory of Physical Chemistry and Chemical Engineering, Xiamen University, 361005 Xiamen, P. R. China
| | - Jinshuai Song
- Institute of Chemistry and the Lise Meitner-Minerva Center for Computational Quantum Chemistry, Hebrew University of Jerusalem, Givat Ram Campus, 91904 Jerusalem, Israel, State Key Laboratory of Physical Chemistry and Chemical Engineering, Xiamen University, 361005 Xiamen, P. R. China
| | - Wenzhen Lai
- Institute of Chemistry and the Lise Meitner-Minerva Center for Computational Quantum Chemistry, Hebrew University of Jerusalem, Givat Ram Campus, 91904 Jerusalem, Israel, State Key Laboratory of Physical Chemistry and Chemical Engineering, Xiamen University, 361005 Xiamen, P. R. China
| | - Wei Wu
- Institute of Chemistry and the Lise Meitner-Minerva Center for Computational Quantum Chemistry, Hebrew University of Jerusalem, Givat Ram Campus, 91904 Jerusalem, Israel, State Key Laboratory of Physical Chemistry and Chemical Engineering, Xiamen University, 361005 Xiamen, P. R. China
| | - Sason Shaik
- Institute of Chemistry and the Lise Meitner-Minerva Center for Computational Quantum Chemistry, Hebrew University of Jerusalem, Givat Ram Campus, 91904 Jerusalem, Israel, State Key Laboratory of Physical Chemistry and Chemical Engineering, Xiamen University, 361005 Xiamen, P. R. China
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48
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Yuan X, Wang Q, Horner JH, Sheng X, Newcomb M. Kinetics and activation parameters for oxidations of styrene by Compounds I from the cytochrome P450(BM-3) (CYP102A1) heme domain and from CYP119. Biochemistry 2009; 48:9140-6. [PMID: 19708688 DOI: 10.1021/bi901258m] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cytochrome P450 (CYP or P450) enzymes are ubiquitous in nature where they catalyze a vast array of oxidation reactions. The active oxidants in P450s have long been assumed to be iron(IV)-oxo porphyrin radical cations termed Compounds I, but P450 Compounds I have proven to be difficult to prepare. The recent development of an entry to these transients by photo-oxidation of the corresponding iron(IV)-oxo neutral porphyrin species (Compounds II) permits spectroscopic and kinetic studies. We report here application of the photo-oxidation method for production of Compound I from the heme domain of CYP102A1 (cytochrome P450(BM-3)), and product and kinetic studies of reactions of styrene with this Compound I transient and also Compound I from CYP119. The studies were performed at low temperatures in 1:1 (v:v) mixtures of glycerol and phosphate buffer. Single-turnover reactions at 0 degrees C gave styrene oxide in good yields. In kinetic studies conducted between -10 and -50 degrees C, both Compounds I displayed saturation kinetics permitting determinations of binding constants and first-order oxidation rate constants. Temperature-dependent functions for the binding constants and rate constants were determined for both Compounds I. In the temperature range studied, the Compound I transient from the CYP102A1 heme domain bound styrene more strongly than Compound I from CYP119, but the rate constants for oxidations of styrene by the latter were somewhat larger than those for the former. The temperature-dependent functions for the first-order oxidation reactions are as follows: log k = 13.2-15.2/2.303RT and log k = 13.3-14.6/2.303RT (kilocalories per mole) for Compounds I from the CYP102A1 heme domain and CYP119, respectively.
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Affiliation(s)
- Xinting Yuan
- Department of Chemistry, University of Illinois, 845 West Taylor Street, Chicago, Illinois 60607, USA
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