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Liu Y, Zhu M, Hu Y, Zhao Y, Zhu C. Photochemical reaction of superoxide radicals with 1-naphthol. CAN J CHEM 2021. [DOI: 10.1139/cjc-2021-0028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The photochemical reactions between 1-naphthol (1-NP) and the superoxide anion radical (O2•–) were investigated in detail by using 365 nm UV irradiation. The results showed that the conversion rate of 1-NP decreased with the increase of the initial concentration of 1-NP, whereas by increasing the pH and riboflavin concentration, the photochemical reaction was accelerated. The second-order reaction rate constant was estimated to be (3.64 ± 0.17) × 108 L mol−1 s−1. The major photolysis products identified by using gas chromatography – mass spectrometry (GC–MS) were 1,4-naphquinone and 2,3-epoxyresin-2,3-dihydro-1,4-naphquinone, and their reaction pathways were also discussed. An atmospheric model showed that both the bulk water reaction and the heterogeneous surface reaction deserve attention in atmospheric aqueous chemistry.
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Affiliation(s)
- Ying Liu
- School of Resources and Environmental Engineering, Hefei University of Technology, Hefei 230009, P.R. China
- Institute of Atmospheric Environment & Pollution Control, Hefei University of Technology, Hefei 230009, P.R. China
- Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology, Hefei 230009, P.R. China
| | - Mengyu Zhu
- School of Resources and Environmental Engineering, Hefei University of Technology, Hefei 230009, P.R. China
- Institute of Atmospheric Environment & Pollution Control, Hefei University of Technology, Hefei 230009, P.R. China
- Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology, Hefei 230009, P.R. China
| | - Yadong Hu
- School of Resources and Environmental Engineering, Hefei University of Technology, Hefei 230009, P.R. China
- Institute of Atmospheric Environment & Pollution Control, Hefei University of Technology, Hefei 230009, P.R. China
- Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology, Hefei 230009, P.R. China
| | - Yijun Zhao
- School of Resources and Environmental Engineering, Hefei University of Technology, Hefei 230009, P.R. China
- Institute of Atmospheric Environment & Pollution Control, Hefei University of Technology, Hefei 230009, P.R. China
- Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology, Hefei 230009, P.R. China
| | - Chengzhu Zhu
- School of Resources and Environmental Engineering, Hefei University of Technology, Hefei 230009, P.R. China
- Institute of Atmospheric Environment & Pollution Control, Hefei University of Technology, Hefei 230009, P.R. China
- Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology, Hefei 230009, P.R. China
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2
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Law BJC, Zhuo Y, Winn M, Francis D, Zhang Y, Samborskyy M, Murphy A, Ren L, Leadlay PF, Micklefield J. A vitamin K-dependent carboxylase orthologue is involved in antibiotic biosynthesis. Nat Catal 2018. [DOI: 10.1038/s41929-018-0178-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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3
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Abstract
Many oxidation-reduction (redox) enzymes, particularly oxygenases, have roles in reactions that make and break C-C bonds. The list includes cytochrome P450 and other heme-based monooxygenases, heme-based dioxygenases, nonheme iron mono- and dioxygenases, flavoproteins, radical S-adenosylmethionine enzymes, copper enzymes, and peroxidases. Reactions involve steroids, intermediary metabolism, secondary natural products, drugs, and industrial and agricultural chemicals. Many C-C bonds are formed via either (i) coupling of diradicals or (ii) generation of unstable products that rearrange. C-C cleavage reactions involve several themes: (i) rearrangement of unstable oxidized products produced by the enzymes, (ii) oxidation and collapse of radicals or cations via rearrangement, (iii) oxygenation to yield products that are readily hydrolyzed by other enzymes, and (iv) activation of O2 in systems in which the binding of a substrate facilitates O2 activation. Many of the enzymes involve metals, but of these, iron is clearly predominant.
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Affiliation(s)
- F Peter Guengerich
- Department of Biochemistry , Vanderbilt University School of Medicine , Nashville , Tennessee 37232-0146 , United States.,Department of Chemistry , University of Texas-San Antonio , San Antonio , Texas 78249-0698 , United States
| | - Francis K Yoshimoto
- Department of Biochemistry , Vanderbilt University School of Medicine , Nashville , Tennessee 37232-0146 , United States.,Department of Chemistry , University of Texas-San Antonio , San Antonio , Texas 78249-0698 , United States
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Kamo S, Yoshioka K, Kuramochi K, Tsubaki K. Total Syntheses of Juglorescein and Juglocombins A and B. Angew Chem Int Ed Engl 2016; 55:10317-20. [DOI: 10.1002/anie.201604765] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Indexed: 11/08/2022]
Affiliation(s)
- Shogo Kamo
- Graduate School for Life and Environmental Sciences; Kyoto Prefectural University; 1-5 Shimogamo Hanki-cho Sakyo-ku Kyoto 606-8522 Japan
| | - Kai Yoshioka
- Graduate School for Life and Environmental Sciences; Kyoto Prefectural University; 1-5 Shimogamo Hanki-cho Sakyo-ku Kyoto 606-8522 Japan
| | - Kouji Kuramochi
- Graduate School for Life and Environmental Sciences; Kyoto Prefectural University; 1-5 Shimogamo Hanki-cho Sakyo-ku Kyoto 606-8522 Japan
- Present address: Department of Applied Biological Science, Faculty of Science and Technology; Tokyo University of Science; 2641 Yamazaki Noda Chiba 278-8510 Japan
| | - Kazunori Tsubaki
- Graduate School for Life and Environmental Sciences; Kyoto Prefectural University; 1-5 Shimogamo Hanki-cho Sakyo-ku Kyoto 606-8522 Japan
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Affiliation(s)
- Shogo Kamo
- Graduate School for Life and Environmental Sciences; Kyoto Prefectural University; 1-5 Shimogamo Hanki-cho Sakyo-ku Kyoto 606-8522 Japan
| | - Kai Yoshioka
- Graduate School for Life and Environmental Sciences; Kyoto Prefectural University; 1-5 Shimogamo Hanki-cho Sakyo-ku Kyoto 606-8522 Japan
| | - Kouji Kuramochi
- Graduate School for Life and Environmental Sciences; Kyoto Prefectural University; 1-5 Shimogamo Hanki-cho Sakyo-ku Kyoto 606-8522 Japan
- Present address: Department of Applied Biological Science, Faculty of Science and Technology; Tokyo University of Science; 2641 Yamazaki Noda Chiba 278-8510 Japan
| | - Kazunori Tsubaki
- Graduate School for Life and Environmental Sciences; Kyoto Prefectural University; 1-5 Shimogamo Hanki-cho Sakyo-ku Kyoto 606-8522 Japan
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Abstract
The first total syntheses of rubialatins A and B, two newly discovered naphthohydroquinone dimers, were achieved with high efficiency and elegancy through rationally designed biomimetic approaches. The tandem ring contraction/Michael addition/aldol reaction followed by oxidation enabled the rapid access of prerubialatin from readily available precursors, which then diverted into rubialatins A and B via epoxidation and photoinduced skeletal rearrangement, respectively. Moreover, several new rubialatin congeners were also obtained along the synthetic tour, some of which were proved to be authentic natural products.
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Affiliation(s)
| | | | | | - Yefeng Tang
- ‡Collaborative Innovation Center for Biotherapy, Tsinghua University, Beijing 100084, China.,§Collaborative Innovation Center for Biotherapy, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China
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Maruo S, Nishio K, Sasamori T, Tokitoh N, Kuramochi K, Tsubaki K. Biomimetic Synthesis of Zeylanone and Zeylanone Epoxide by Dimerization of 2-Methyl-1,4-naphthoquinone. Org Lett 2013; 15:1556-9. [DOI: 10.1021/ol400335s] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sayako Maruo
- Graduate School for Life and Environmental Sciences, Kyoto Prefectural University, 1-5 Shimogamo Hangi-cho, Sakyo-ku, Kyoto 606-8522, Japan, and Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Kazuyuki Nishio
- Graduate School for Life and Environmental Sciences, Kyoto Prefectural University, 1-5 Shimogamo Hangi-cho, Sakyo-ku, Kyoto 606-8522, Japan, and Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Takahiro Sasamori
- Graduate School for Life and Environmental Sciences, Kyoto Prefectural University, 1-5 Shimogamo Hangi-cho, Sakyo-ku, Kyoto 606-8522, Japan, and Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Norihiro Tokitoh
- Graduate School for Life and Environmental Sciences, Kyoto Prefectural University, 1-5 Shimogamo Hangi-cho, Sakyo-ku, Kyoto 606-8522, Japan, and Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Kouji Kuramochi
- Graduate School for Life and Environmental Sciences, Kyoto Prefectural University, 1-5 Shimogamo Hangi-cho, Sakyo-ku, Kyoto 606-8522, Japan, and Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Kazunori Tsubaki
- Graduate School for Life and Environmental Sciences, Kyoto Prefectural University, 1-5 Shimogamo Hangi-cho, Sakyo-ku, Kyoto 606-8522, Japan, and Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
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8
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Affiliation(s)
| | - Wei-chen Chang
- College of Pharmacy and Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712
| | - Hung-wen Liu
- Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, Texas 78712
- College of Pharmacy and Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, Texas 78712
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Suhara Y, Murakami A, Nakagawa K, Mizuguchi Y, Okano T. Comparative uptake, metabolism, and utilization of menaquinone-4 and phylloquinone in human cultured cell lines. Bioorg Med Chem 2006; 14:6601-7. [PMID: 16798001 DOI: 10.1016/j.bmc.2006.06.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2006] [Revised: 06/01/2006] [Accepted: 06/02/2006] [Indexed: 12/31/2022]
Abstract
It is generally accepted that the availability of vitamin K in vivo depends on its homologues, the biological activities of which would differ among organs. To test this hypothesis, we examined the uptake, metabolism, and utilization of menaquinone-4 (MK-4) and phylloquinone (PK) using 18O-labeled compounds in two cultured human cell lines (HepG2 and MG-63). Lipid extracts were prepared from the cells and media after 1, 3, and 6h of incubation. The detection of the vitamin K analogues (18O-, 16O-quinone, and epoxide forms) was carried out with LC-APCI-MS/MS as previously reported. The 18O of vitamin K was replaced with atmospheric 16O2 during the formation of vitamin K epoxide with a carboxylative catalytic reaction. As a result, a significant difference was observed between MK-4 and PK in the amounts taken up into the cells. The 18O-labeled MK-4 was rapidly and remarkably well absorbed into the cells and metabolized to the epoxide form via a hydroquinone form as compared to the 18O-labeled PK. The difference in uptake of MK-4 and PK was not affected by treatment with warfarin although the metabolism of both compounds was markedly inhibited. This methodology should be utilized to clarify some of the actions of vitamin K in target cells and facilitate the development of new vitamin K drugs.
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Affiliation(s)
- Yoshitomo Suhara
- Department of Hygienic Sciences, Kobe Pharmaceutical University, 4-19-1 Motoyamakita-machi, Kobe 658-8558, Japan
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Fosse C, Le Texier L, Roy S, Delaforge M, Grégoire S, Neuwels M, Azerad R. Parameters and mechanistic studies on the oxidative ring cleavage of synthetic heterocyclic naphthoquinones by Streptomyces strains. Appl Microbiol Biotechnol 2004; 65:446-56. [PMID: 15205932 DOI: 10.1007/s00253-004-1588-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2003] [Revised: 02/04/2004] [Accepted: 02/06/2004] [Indexed: 11/27/2022]
Abstract
Screening of fungal and bacterial strains allowed selection of two Streptomyces strains ( S. platensis and S. cinnamonensis) that oxidatively cleave, in moderate to high yields (up to 65% in 24 h), the quinonic ring of a thiazole fused 1,4-naphthoquinone compound, INO5042, used as a model compound for a series of homologous substituted heterocyclic naphthoquinones. The respective products of these whole-cell biotransformations were identified as isomeric phenol-carboxylic acids resulting from a C-C bond cleavage at a position vicinal to each one of the carbonyl groups. The culture and incubation conditions have been optimised and the mechanism of this biotransformation investigated using oxygen isotope incorporation. The results of 18O2 incorporation indicate a dioxygenase reaction, the mechanism of which is discussed in relation with that of hydroquinone-epoxidases, a family of oxygenating enzymes involved in the biosynthesis of polyketide antibiotics in Streptomyces.
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Affiliation(s)
- Céline Fosse
- Groupe Biocatalyse et Chimie Pharmacologique, Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, UMR 8601, Université René Descartes-Paris V, 45 rue des Saints-Pères, 75006, Paris, France
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Zheng YJ, Bruice TC. Rapid Enzyme-Catalyzed Heterolytic C−H Bond Cleavage by a Base Strength Amplification Mechanism: A Theoretical Examination of the Mechanism of Oxidation of Vitamin K. J Am Chem Soc 1998. [DOI: 10.1021/ja973140q] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Ya-Jun Zheng
- Department of Chemistry, University of California Santa Barbara, California 93106
| | - Thomas C. Bruice
- Department of Chemistry, University of California Santa Barbara, California 93106
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14
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Abstract
Energy transfer provides an arrow in the metabolism of living systems. Direct energetic coupling of chemical transformations, such that the free energy generated in one reaction is channeled to another, is the essence of energy transfer, whereas the purpose is the production of high-energy chemical intermediates. Vitamin K provides a particularly instructive example of energy transfer. A key principle at work in the vitamin K system can be termed "base strength amplification." In the base strength amplification sequence, the free energy of oxygenation of vitamin K hydroquinone (vitamin KH2) is used to transform a weak base to a strong base in order to effect proton removal from selected glutamate (Glu) residues in the blood-clotting proteins.
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Affiliation(s)
- P Dowd
- Department of Chemistry, University of Pittsburgh, PA 15260, USA
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15
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Roth DA, Whirl ML, Velazquez-Estades LJ, Walsh CT, Furie B, Furie BC. Mutagenesis of vitamin K-dependent carboxylase demonstrates a carboxyl terminus-mediated interaction with vitamin K hydroquinone. J Biol Chem 1995; 270:5305-11. [PMID: 7890642 DOI: 10.1074/jbc.270.10.5305] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The gamma-glutamyl carboxylase and vitamin K epoxidase activities of a series of mutants of bovine vitamin K-dependent carboxylase with progressively larger COOH-terminal deletions have been analyzed. The recombinant wild-type (residues 1-758) and mutant protein carboxylases, Cbx 711, Cbx 676, and Cbx 572, representing residues 1-711, 1-676, and 1-572, respectively, were expressed in baculovirus-infected Sf9 cells. Wild-type carboxylase had a Km for the substrate Phe-Leu-Glu-Glu-Leu (FLEEL) of 0.87 mM; the carboxylation of FLEEL was stimulated 2.5-fold by proPT18, the propeptide of prothrombin. Its Km for vitamin K hydroquinone was 23 microM and the specific epoxidase activity of the carboxylase was 938 pmol vitamin KO/30 min/pmol of carboxylase. Cbx 711, which was also stimulated by proPT18, had a Km for FLEEL, a Km for vitamin K hydroquinone, and a specific epoxidase activity that was comparable to the wild-type carboxylase. In contrast Cbx 572 lacked both carboxylase and epoxidase activities. Although Cbx 676 had a normal carboxylase active site in terms of the Km for FLEEL and its stimulation by proPT18, the Km for vitamin K hydroquinone was 540 microM, and the specific epoxidase activity was 97 pmol KO/30 min/pmol of Cbx 676. The catalytic efficiencies of Cbx 676 for glutamate carboxylation and vitamin K epoxidation were decreased 15- and 400-fold, respectively, from wild-type enzyme reflecting the requirement for formation of an activated vitamin K species for carboxylation to occur. These data indicate that the truncation of COOH-terminal segments of the carboxylase had no effect on FLEEL or propeptide recognition, but in the case of Cbx 676, selectively affected the interaction with vitamin K hydroquinone and the generation of epoxidase activity. These data suggest that a vitamin K epoxidase activity domain may reside near the COOH terminus while the carboxylase active site domain resides toward the NH2 terminus.
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Affiliation(s)
- D A Roth
- Center for Hemostasis and Thrombosis Research, New England Medical Center, Boston, Massachusetts
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Yamada M, Kuliopulos A, Nelson NP, Roth DA, Furie B, Furie BC, Walsh CT. Localization of the factor IX propeptide binding site on recombinant vitamin K dependent carboxylase using benzoylphenylalanine photoaffinity peptide inactivators. Biochemistry 1995; 34:481-9. [PMID: 7819240 DOI: 10.1021/bi00002a012] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The propeptide binding/activation site on the vitamin K dependent carboxylase has been localized to a region of carboxylase between residues Arg +50 and Glu +225 by photoinactivation studies using [125I]tyrosyl-labeled benzoylphenylalanine (Bpa)-containing analogs of proFIX19, a peptide containing residues -18 to +1 of factor IX. Four proFIX19 analogs with Bpa substituents at -16, -13, -7, and -6 were synthesized. These peptides were specific photoinactivators of carboxylase and were used to label a His6-carboxylase construct produced in baculovirus-infected insect cells. Fragments of the labeled carboxylase produced by V8 protease digestion were analyzed by peptide-specific antibodies and by autoradiography. The propeptide recognition site was localized to the N-terminal one-third of the 94 kDa carboxylase. This is consistent with previous studies using a carboxylase substrate affinity label, N-(bromoacetyl)-FLEELY [Kuliopulos, A., Nelson, N.P., Yamada, M., Walsh, C.T., Furie, B., Furie, B.C., & Roth, D.A. (1994) J. Biol. Chem. 269, 21364-21370], indicating that the propeptide binding site and the FLEEL binding site are both located within the N-terminal one-third of the vitamin K dependent carboxylase.
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Affiliation(s)
- M Yamada
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115
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Shen B, Hutchinson CR. Triple hydroxylation of tetracenomycin A2 to tetracenomycin C in Streptomyces glaucescens. Overexpression of the tcmG gene in Streptomyces lividans and characterization of the tetracenomycin A2 oxygenase. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(18)43874-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Kuliopulos A, Nelson N, Yamada M, Walsh C, Furie B, Furie B, Roth D. Localization of the affinity peptide-substrate inactivator site on recombinant vitamin K-dependent carboxylase. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)31971-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Shen B, Hutchinson CR. Tetracenomycin F1 monooxygenase: oxidation of a naphthacenone to a naphthacenequinone in the biosynthesis of tetracenomycin C in Streptomyces glaucescens. Biochemistry 1993; 32:6656-63. [PMID: 8329392 DOI: 10.1021/bi00077a019] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Tetracenomycin (Tcm) F1 monooxygenase, which catalyzes the oxidation of the naphthacenone Tcm F1 to the 5,12-naphthacenequinone Tcm D3 in the biosynthesis of the anthracycline antibiotic Tcm C in Streptomyces glaucescens, has been purified to homogeneity and characterized. Gel filtration chromatography yields a molecular weight of 37,500 whereas SDS-PAGE gives a single band with a molecular weight of 12,500, indicating that the Tcm F1 monooxygenase is a homotrimer in solution. The N-terminal sequence of the enzyme establishes that it is encoded by the tcmH gene. The monooxygenase displays an optimal pH of 7.5 and has a Km of 7.47 +/- 0.67 microM and Vmax of 473 +/- 10 nmol.min-1.mg-1. Formally, the Tcm F1 monooxygenase can be classified as an internal monooxygenase that requires only O2 for the enzymatic oxidation. Yet, it apparently does not possess any of the prosthetic groups of known monooxygenases, such as flavin or heme groups, nor does it utilize metal ions. It is inactivated by p-chloromercuribenzoic acid, N-ethylmaleimide, and diethyl pyrocarbonate, suggesting that sulfhydryl groups and histidine residues are essential for the enzyme activity.
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Affiliation(s)
- B Shen
- School of Pharmacy, University of Wisconsin, Madison 53706
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Decker H, Motamedi H, Hutchinson CR. Nucleotide sequences and heterologous expression of tcmG and tcmP, biosynthetic genes for tetracenomycin C in Streptomyces glaucescens. J Bacteriol 1993; 175:3876-86. [PMID: 8509339 PMCID: PMC204804 DOI: 10.1128/jb.175.12.3876-3886.1993] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The nucleotide sequence of the tcmIII, tcmIc, and tcmVII region of the tetracenomycin (TCM) C gene cluster of Streptomyces glaucescens ETH 22794 (GLA.0) revealed the presence of two genes, tcmP and tcmG. The deduced product of tcmG resembles flavoprotein hydroxylases found in several other bacteria, whereas the predicted amino acid sequence of tcmP is not significantly similar to those of any known proteins in the available data bases. Southern blot hybridization revealed an approximately 180-bp deletion in a tcmIII (tcmG) mutant and a 1,800-bp insertion in a tcmVII (tcmP) mutant. Heterologous expression of tcmG and tcmP in Streptomyces lividans and tcmP in Escherichia coli established that tcmP encodes an O-methyltransferase, catalyzing the methylation of the C-9 carboxy group of TCM E to yield TCM A2, and that tcmG is responsible for the hydroxylation of TCM A2 at positions C-4, C-4a, and C-12a to give TCM C. These are the final two steps of TCM C biosynthesis.
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Affiliation(s)
- H Decker
- School of Pharmacy, University of Wisconsin, Madison 53706
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