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Avalos D, Sabuncu S, Mamounis KJ, Davidson VL, Moënne-Loccoz P, Yukl ET. Structural and Spectroscopic Characterization of a Product Schiff Base Intermediate in the Reaction of the Quinoprotein Glycine Oxidase, GoxA. Biochemistry 2019; 58:706-713. [PMID: 30605596 DOI: 10.1021/acs.biochem.8b01145] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The LodA-like proteins make up a recently identified family of enzymes that rely on a cysteine tryptophylquinone cofactor for catalysis. They differ from other tryptophylquinone enzymes in that they are oxidases rather than dehydrogenases. GoxA is a member of this family that catalyzes the oxidative deamination of glycine. Our previous work with GoxA from Pseudoalteromonas luteoviolacea demonstrated that this protein forms a stable intermediate upon anaerobic incubation with glycine. The spectroscopic properties of this species were unique among those identified for tryptophylquinone enzymes characterized to date. Here we use X-ray crystallography and resonance Raman spectroscopy to identify the GoxA catalytic intermediate as a product Schiff base. Structural work additionally highlights features of the active site pocket that confer substrate specificity, intermediate stabilization, and catalytic activity. The unusual properties of GoxA are discussed within the context of the other tryptophylquinone enzymes.
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Affiliation(s)
- Dante Avalos
- Department of Chemistry and Biochemistry , New Mexico State University , Las Cruces , New Mexico 88003 , United States
| | - Sinan Sabuncu
- Department of Biochemistry and Molecular Biology, School of Medicine , Oregon Health & Science University , Portland , Oregon 97239 , United States
| | - Kyle J Mamounis
- Burnett School of Biomedical Sciences, College of Medicine , University of Central Florida , Orlando , Florida 32827 , United States
| | - Victor L Davidson
- Burnett School of Biomedical Sciences, College of Medicine , University of Central Florida , Orlando , Florida 32827 , United States
| | - Pierre Moënne-Loccoz
- Department of Biochemistry and Molecular Biology, School of Medicine , Oregon Health & Science University , Portland , Oregon 97239 , United States
| | - Erik T Yukl
- Department of Chemistry and Biochemistry , New Mexico State University , Las Cruces , New Mexico 88003 , United States
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Tian Y, Ye S, Ran Q, Xian Y, Xu J, Peng R, Jin L. Generation of surface-confined catechol terminated SAMs via electrochemically triggered Michael addition: characterization, electrochemistry and complex with Ni(ii) and Cu(ii) cations. Phys Chem Chem Phys 2010; 12:13287-95. [DOI: 10.1039/c001205j] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Pang J, Scrutton NS, Visser SPD, Sutcliffe MJ. Assignment of the Vibrational Spectra of Enzyme-Bound Tryptophan Tryptophyl Quinones Using a Combined QM/MM Approach. J Phys Chem A 2009; 114:1212-7. [DOI: 10.1021/jp910161k] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Jiayun Pang
- Manchester Interdisciplinary Biocentre, School of Chemical Engineering and Analytical Science, and Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Nigel S. Scrutton
- Manchester Interdisciplinary Biocentre, School of Chemical Engineering and Analytical Science, and Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Sam P. de Visser
- Manchester Interdisciplinary Biocentre, School of Chemical Engineering and Analytical Science, and Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Michael J. Sutcliffe
- Manchester Interdisciplinary Biocentre, School of Chemical Engineering and Analytical Science, and Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
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Nuñez S, Tresadern G, Hillier IH, Burton NA. An analysis of reaction pathways for proton tunnelling in methylamine dehydrogenase. Philos Trans R Soc Lond B Biol Sci 2006; 361:1387-98. [PMID: 16873126 PMCID: PMC1647307 DOI: 10.1098/rstb.2006.1867] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Computational methods have now become a valuable tool to understand the way in which enzymes catalyse chemical reactions and to aid the interpretation of a diverse set of experimental data. This study focuses on the influence of the condensed-phase environment structure on proton transfer mechanisms, with an aim to understand how C-H bond cleavage is mediated in enzymatic reactions. We shall use a combination of molecular simulation, ab initio or semi-empirical quantum chemistry and semi-classical multidimensional tunnelling methods to consider the primary kinetic isotope effects of the enzyme methylamine dehydrogenase (MADH), with reference to an analogous application to triosephosphate isomerase. Analysis of potentially reactive conformations of the system, and correlation with experimental isotope effects, have highlighted that a quantum tunnelling mechanism in MADH may be modulated by specific amino acid residues, such as Asp428, Thr474 and Asp384.
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Okamoto K, Ohkubo K, Kadish KM, Fukuzumi S. Remarkable Accelerating Effects of Ammonium Cations on Electron-Transfer Reactions of Quinones by Hydrogen Bonding with Semiquinone Radical Anions. J Phys Chem A 2004. [DOI: 10.1021/jp046078+] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Zou JW, Liang JM, Yu CH. Regioselectivity for condensation reactions of quinonoid models of tryptophan tryptophylquinone: a density functional theory study. J Org Chem 2003; 68:3626-33. [PMID: 12713371 DOI: 10.1021/jo026793k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The model compounds of tryptophan tryptophylquinone (TTQ), o-benzoquinone (OBQ), 3-methyl-6,7-dihydro-1H-6,7-indoledione (MIQ), and 3-methyl-4-(3-methyl-1H-2-indolyl)-6,7-dihydro-1H-6,7-indoledione (IIQ), all of which are characteristic of o-quinone groups, have been studied with density functional theory. The dihedral angle of the two indole rings (chi) of IIQ is calculated to be 49.6 degrees for the global minimum. Another local minimum, 0.74 kcal/mol higher in energy, with a chi value of 123.5 degrees is also fully optimized. The transition state connecting the two minima, with a chi value of 97.9 degrees, has been located and the rotation barrier is 1.71 kcal/mol. A scan of the potential energy surface along this dihedral angle showed that the difference of the total energy was within 1.0 kcal/mol at a range of the dihedral angle from 30 degrees to 75 degrees. Hence, IIQ is flexible for the rotation of inter-indole rings. The origin of regioselectivity for the condensation reactions of the models MIQ and IIQ with NH(3) has been elucidated. It is shown that the energy difference between the two different types of carbinolamine intermediates (Delta E) and their corresponding transition structures (Delta E(++)) should be responsible for the regioselectivity. To assess the effect of the fused ring on regioselectivity of the condensation reaction, a series of models were designed. A good linear correlation has been found between the energy difference of the two different carbinolamine intermediates (Delta E) and that of the corresponding transition states (Delta E(++)), suggesting that the factors that stabilize the carbinolamine intermediate also favor the stability of the corresponding transition structure. The pair, 6-amino-6-hydroxy-8-methyl-6H-quinolin-5-one and 5-amino-5-hydroxy-8-methyl-5H-quinolin-6-one (7/8), deviates from the correlation and represents some anomalous behavior, which may be due to their structural particularity. It also has been shown that the tricyclic models, which consist of OBQ and two fused heterocyclic rings, represent more regioselectivity in contrast to the bicyclic systems. Moreover, the fused electron-donating pyrrole and the fused electron-withdrawing pyridine or pyrimidine show a somewhat synergistic effect on each other via the medial OBQ molecule. The barrier of the condensation reaction for pyrrolo[2,3-f]quinoline-4,5-dione is calculated to be ca. 22 kcal/mol. This is lower than that for MIQ (ca. 33 kcal/mol) and IIQ (ca. 32 kcal/mol) by as much as 10.0 kcal/mol, explaining reasonably the larger catalytic effect of pyrroloquinolinequinone (PQQ) relative to TTQ.
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Affiliation(s)
- Jian-Wei Zou
- Department of Chemistry, National Tsing Hua University, Hsinchu 300, Taiwan
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Abstract
Redox coenzymes and analogs have their own redox reactivities for both thermal and photochemical redox reactions. The redox activities of coenzymes can be tuned by using metal ions that can bind the redox coenzymes and analogs. Quantitative measure to determine the Lewis acidity of a variety of metal ions is given in relation to the catalytic reactivities. The mechanistic viability of metal ion catalysis in redox reactions of coenzyme analogs is described by showing a number of examples of both thermal and photochemical reactions that are made possible to proceed by controlling the redox reactivities of coenzymes with metal ions.
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Affiliation(s)
- S Fukuzumi
- Department of Material and Life Science, Graduate School of Engineering, Osaka University, CREST, JAPAN Science and Technology Corporation, Suita.
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Schwartz B, Klinman JP. Mechanisms of biosynthesis of protein-derived redox cofactors. VITAMINS AND HORMONES 2001; 61:219-39. [PMID: 11153267 DOI: 10.1016/s0083-6729(01)61007-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Prior to 1990, redox cofactors were widely believed to be small molecule, dissociable compounds. In the past 10 years, however, four novel redox cofactors have been discovered, each of which is derived from posttranslational modification of specific amino acids within their cognate enzymes. These include topa quinone, found in copper amine oxidases, lysine tyrosyl quinone, found in lysyl oxidase, tryptophan tryptophylquinone, found in methylamine dehydrogenase, and the cysteine-cross-linked tyrosine found in galactose oxidase. The processes by which these cofactors are formed, called biogenesis, is currently a major focus of mechanistic work in this field. In this review, the latest progress toward elucidating the various biogenesis mechanisms is discussed, along with possible linkages between the chemistries involved in catalysis and biogenesis.
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Affiliation(s)
- B Schwartz
- Departments of Chemistry and Molecular Biology, University of California, Berkeley, California 94704, USA
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Coenzymes of Oxidation—Reduction Reactions. Biochemistry 2001. [DOI: 10.1016/b978-012492543-4/50018-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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10
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Itoh S, Taniguchi M, Takada N, Nagatomo S, Kitagawa T, Fukuzumi S. Effects of Metal Ions on the Electronic, Redox, and Catalytic Properties of Cofactor TTQ of Quinoprotein Amine Dehydrogenases. J Am Chem Soc 2000. [DOI: 10.1021/ja0020207] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Shinobu Itoh
- Contribution from the Department of Chemistry, Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan, Department of Material and Life Science, Graduate School of Engineering, Osaka University, CREST, Japan Science and Technology Corporation, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan, and Institute for Molecular Science, Myodaiji, Okazaki 444-8585, Japan
| | - Masato Taniguchi
- Contribution from the Department of Chemistry, Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan, Department of Material and Life Science, Graduate School of Engineering, Osaka University, CREST, Japan Science and Technology Corporation, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan, and Institute for Molecular Science, Myodaiji, Okazaki 444-8585, Japan
| | - Naoki Takada
- Contribution from the Department of Chemistry, Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan, Department of Material and Life Science, Graduate School of Engineering, Osaka University, CREST, Japan Science and Technology Corporation, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan, and Institute for Molecular Science, Myodaiji, Okazaki 444-8585, Japan
| | - Shigenori Nagatomo
- Contribution from the Department of Chemistry, Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan, Department of Material and Life Science, Graduate School of Engineering, Osaka University, CREST, Japan Science and Technology Corporation, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan, and Institute for Molecular Science, Myodaiji, Okazaki 444-8585, Japan
| | - Teizo Kitagawa
- Contribution from the Department of Chemistry, Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan, Department of Material and Life Science, Graduate School of Engineering, Osaka University, CREST, Japan Science and Technology Corporation, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan, and Institute for Molecular Science, Myodaiji, Okazaki 444-8585, Japan
| | - Shunichi Fukuzumi
- Contribution from the Department of Chemistry, Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan, Department of Material and Life Science, Graduate School of Engineering, Osaka University, CREST, Japan Science and Technology Corporation, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan, and Institute for Molecular Science, Myodaiji, Okazaki 444-8585, Japan
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12
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Zhu Z, Davidson VL. Kinetic and chemical mechanisms for the effects of univalent cations on the spectral properties of aromatic amine dehydrogenase. Biochem J 1998; 329 ( Pt 1):175-82. [PMID: 9405291 PMCID: PMC1219029 DOI: 10.1042/bj3290175] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Univalent cations and pH influence the UV-visible absorption spectrum of the tryptophan tryptophylquinone (TTQ) enzyme, aromatic amine dehydrogenase (AADH). Little spectral perturbation was observed when pH was varied in the absence of univalent cations. The addition of alkali metal univalent cations (K+, Na+, Li+, Rb+ or Cs+) to oxidized AADH caused significant changes in its absorption spectrum. The apparent Kd for each cation, determined from titrations of the spectral perturbation, decreased with increasing pH. Transient kinetic studies involving rapid mixing of AADH with cations and pH jump revealed that the rate of the cation-induced spectral changes initially decreased with increasing cation concentration to a minimum value, then increased with increasing cation concentration. A kinetic model was developed to fit these data, determine the true pH-independent Kd values for K+ and Na+, and explain the pH-dependence of the apparent Kd. A chemical reaction mechanism, based on the kinetic data, is presented in which the metallic univalent cation facilitates the chemical modification of the TTQ prosthetic group to form an hydroxide adduct which gives rise to the spectral change. Addition of NH4(+)/NH3 to AADH caused changes in the absorption spectrum which were very different form those caused by addition of the metallic univalent cations. The kinetics of the reaction induced by addition of NH4+/NH3 were also different, being simple saturation kinetics. Another reaction mechanism is proposed for the NH4+/NH3-induced spectral change that involves nucleophilic addition of the unprotonated NH3 to TTQ. The general relevance of these data and models to the physiological reactions of TTQ-dependent enzymes and to the roles of univalent cations in modulating enzyme activity are discussed.
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Affiliation(s)
- Z Zhu
- Department of Biochemistry, University of Mississippi Medical Center, Jackson, MS 39216-4505, USA
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Dennison C, Canters G, Vries S, Vijgenboom E, Spanning R. The Methylamine Dehydrogenase Electron Transfer Chain. ADVANCES IN INORGANIC CHEMISTRY 1998. [DOI: 10.1016/s0898-8838(08)60029-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Itoh S, Takada N, Ando T, Haranou S, Huang X, Uenoyama Y, Ohshiro Y, Komatsu M, Fukuzumi S. Synthesis, Physicochemical Properties, and Amine-Oxidation Reaction of Indolequinone Derivatives as Model Compounds of Novel Organic Cofactor TTQ of Amine Dehydrogenases. J Org Chem 1997. [DOI: 10.1021/jo970716l] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Shinobu Itoh
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565, Japan
| | - Naoki Takada
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565, Japan
| | - Takeya Ando
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565, Japan
| | - Shigenobu Haranou
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565, Japan
| | - Xin Huang
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565, Japan
| | - Yasushi Uenoyama
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565, Japan
| | - Yoshiki Ohshiro
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565, Japan
| | - Mitsuo Komatsu
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565, Japan
| | - Shunichi Fukuzumi
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565, Japan
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Affiliation(s)
- C Hartmann
- Department of Veterans Affairs Medical Center, Molecular Biology Division (151-S), San Francisco, California 94121, USA
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Abstract
This review is concerned with the structure and function of the quinoprotein enzymes, sometimes called quinoenzymes. These have prosthetic groups containing quinones, the name thus being analogous to the flavoproteins containing flavin prosthetic groups. Pyrrolo-quinoline quinone (PQQ) is non-covalently attached, whereas tryptophan tryptophylquinone (TTQ), topaquinone (TPQ) and lysine tyrosylquinone (LTQ) are derived from amino acid residues in the backbone of the enzymes. The mechanisms of the quinoproteins are reviewed and related to their recently determined three-dimensional structures. As expected, the quinone structures in the prosthetic groups play important roles in the mechanisms. A second common feature is the presence of a catalytic base (aspartate) at the active site which initiates the reactions by abstracting a proton from the substrate, and it is likely to be involved in multiple reactions in the mechanism. A third common feature of these enzymes is that the first part of the reaction produces a reduced prosthetic group; this part of the mechanism is fairly well understood. This is followed by an oxidative phase involving electron transfer reactions which remain poorly understood. In both types of dehydrogenase (containing PQQ and TTQ), electrons must pass from the reduced prosthetic group to redox centres in a second recipient protein (or protein domain), whereas in amine oxidases (containing TPQ or LTQ), electrons must be transferred to molecular oxygen by way of a redox-active copper ion in the protein.
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Affiliation(s)
- C Anthony
- Biochemistry Department, University of Southampton, U.K
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Itoh S, Takada N, Haranou S, Ando T, Komatsu M, Ohshiro Y, Fukuzumi S. Model Studies of TTQ-Containing Amine Dehydrogenases. J Org Chem 1996; 61:8967-8974. [PMID: 11667879 DOI: 10.1021/jo961705f] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The reactions of a TTQ model compound [1, 3-methyl-4-(3'-methylindol-2'-yl)indole-6,7-dione] with several amines have been investigated in organic media to obtain mechanistic information on the action of quinoprotein methylamine and aromatic amine dehydrogenases. It has been found that compound 1 acts as an efficient catalyst for the autorecycling oxidation of benzylamine by molecular oxygen in CH(3)OH. In order to evaluate the oxidation mechanism of amines by 1, the product analyses and kinetic studies have been carried out under anaerobic conditions. In the first stage of the reaction of 1 with amines, 1 is converted into an iminoquinone-type adduct (so-called substrateimine), which was isolated and characterized by using cyclopropylamine as a substrate. The observed NOE of the isolated product indicates clearly that the addition position of the amine is C-6 of the quinone. The molecular orbital calculations suggest that the thermodynamic stability of the carbinolamine intermediate is a major factor to determine such regioselectivity; the C-6 carbinolamine is more stable than the C-7 counterpart by 2.9 kcal/mol. The reactivity of several primary amines and the electronic effect of the p-substituents of benzylamine derivatives in the iminoquinone formation suggest that the addition step of the amine to the quinone is rate-determining. When amines having an acidic alpha-proton such as benzylamine derivatives are employed as substrates, formation of the iminoquinone adduct was followed by rearrangement to the productimine. The kinetic analysis has revealed that this rearrangement consists of noncatalyzed and general base-catalyzed processes. Large kinetic isotope effects of 7.8 and 9.2 were observed for both the noncatalyzed and general base-catalyzed processes, respectively, since these steps involve a proton abstraction from the alpha-position of the substrate. In the reaction with benzhydrylamine, the product imine was isolated quantitatively and well characterized by several spectroscopic data. In the case of benzylamine, the product imine is further converted into the aminophenol derivative by the imine exchange reaction with excess benzylamine. These results indicate clearly that the amine oxidation by compound 1 proceeds via a transamination mechanism as suggested for the enzymatic oxidation of amines by TTQ cofactor.
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Affiliation(s)
- Shinobu Itoh
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, Yamada-oka 2-1, Suita, Osaka 565, Japan
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