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Caetano MS, Freitas MP, da Cunha EFF, Ramalho TC. Construction and assessment of reaction models of Class I EPSP synthase. Part II: investigation of the EPSP ketal. J Biomol Struct Dyn 2013; 31:393-402. [PMID: 22877309 DOI: 10.1080/07391102.2012.703066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Although the proposed mechanisms are reasonable, there are still many questions about the 5-enolpyruvyl shikimate-3-phosphate (EPSP) synthase mechanism that are difficult to answer by experimental means alone. EPSP synthase is a key enzyme in the shikimic acid pathway, which is found only in plants and some micro-organisms and is also molecular target of glyphosate, active component of one of the top-selling herbicides. In the study of reaction mechanism of EPSP synthase, in addition to inorganic phosphate and EPSP products, after long time at equilibrium, it was shown that a side product is formed, the EPSP ketal. In this line, studies using density functional theory (DFT) techniques were performed to investigate the reaction mechanism of formation of EPSP and the corresponding ketal. Our findings indicate some key amino acid residues in the EPSP synthase mechanism and a possible route for the formation of the EPSP ketal.
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Domínguez de María P, van Gemert RW, Straathof AJJ, Hanefeld U. Biosynthesis of ethers: unusual or common natural events? Nat Prod Rep 2010; 27:370-92. [PMID: 20179877 DOI: 10.1039/b809416k] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ether bonds are found in a wide variety of natural products--mainly secondary metabolites--including lipids, oxiranes, terpenoids, flavonoids, polyketides, and carbohydrate derivatives, to name some representative examples. To furnish such a biodiversity of structures, a large number of different enzymes are involved in several different biosynthetic pathways. Depending on the compound and on the (micro) environment in which the reaction is performed, ethers are produced by very different (enzymatic) reactions, thus providing an impressive display of how Nature has combined evolution and thermodynamics to be able to produce a vast number of compounds. In addition, many of these compounds possess different biological activities of pharmacological interest. Moreover, some of these ethers (i.e., epoxides) have high chemical reactivity, and can be useful starting materials for further synthetic processes. This review aims to provide an overview of the different strategies that are found in Nature for the formation of these "bioethers". Both fundamental and practical insights of the biosynthetic processes will be discussed.
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Vogt FG, Mattingly SM, Gibson JM, Mueller KT. Measurement of internuclear distances in solid-state NMR by a background-filtered REDOR experiment. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2000; 147:26-35. [PMID: 11042044 DOI: 10.1006/jmre.2000.2165] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A background-filtered version of the rotational-echo double resonance (REDOR) experiment is demonstrated. The experiment combines a traditional REDOR pulse sequence with a double-cross-polarization (DCP) sequence to select only those signals coming from spin pairs of interest. The relatively inefficient DCP sequence, which transfers polarization from (1)H to (15)N and subsequently to (13)C, is improved by the use of adiabatic passages through the (-1) sideband of the Hartmann-Hahn matching condition. The result is an efficient 2D-REDOR pulse sequence that does not require a reference experiment for removal of background signals. The data produced by the experiment are ideally suited to analysis by newly developed dipolar transform methods, such as the REDOR transform. The relevant features of the experiment are demonstrated on simple labeled amino acids. Relative efficiencies of several other potential filtering methods are also compared. Copyright 2000 Academic Press.
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Affiliation(s)
- FG Vogt
- Department of Chemistry, The Pennsylvania State University, 152 Davey Laboratory, University Park, Pennsylvania, 16802-6300, USA
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Goetz JM, Poliks B, Studelska DR, Fischer M, Kugelbrey K, Bacher A, Cushman M, Schaefer J. Investigation of the Binding of Fluorolumazines to the 1-MDa Capsid of Lumazine Synthase by 15N{19F} REDOR NMR. J Am Chem Soc 1999. [DOI: 10.1021/ja983792u] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jon M. Goetz
- Contribution from the Department of Chemistry, Washington University, Saint Louis, Missouri 63130, Department of Physics, State University of New York at Binghamton, Binghamton, New York 13902, Lehrstuhl für Organische Chemie und Biochemie, Technische Universität München, D-85747 Garching, Germany, and Department of Medicinal Chemistry and Molecular Pharmacology, School of Pharmacy, Purdue University, West Lafayette, Indiana 47907
| | - Barbara Poliks
- Contribution from the Department of Chemistry, Washington University, Saint Louis, Missouri 63130, Department of Physics, State University of New York at Binghamton, Binghamton, New York 13902, Lehrstuhl für Organische Chemie und Biochemie, Technische Universität München, D-85747 Garching, Germany, and Department of Medicinal Chemistry and Molecular Pharmacology, School of Pharmacy, Purdue University, West Lafayette, Indiana 47907
| | - Daniel R. Studelska
- Contribution from the Department of Chemistry, Washington University, Saint Louis, Missouri 63130, Department of Physics, State University of New York at Binghamton, Binghamton, New York 13902, Lehrstuhl für Organische Chemie und Biochemie, Technische Universität München, D-85747 Garching, Germany, and Department of Medicinal Chemistry and Molecular Pharmacology, School of Pharmacy, Purdue University, West Lafayette, Indiana 47907
| | - Markus Fischer
- Contribution from the Department of Chemistry, Washington University, Saint Louis, Missouri 63130, Department of Physics, State University of New York at Binghamton, Binghamton, New York 13902, Lehrstuhl für Organische Chemie und Biochemie, Technische Universität München, D-85747 Garching, Germany, and Department of Medicinal Chemistry and Molecular Pharmacology, School of Pharmacy, Purdue University, West Lafayette, Indiana 47907
| | - Karl Kugelbrey
- Contribution from the Department of Chemistry, Washington University, Saint Louis, Missouri 63130, Department of Physics, State University of New York at Binghamton, Binghamton, New York 13902, Lehrstuhl für Organische Chemie und Biochemie, Technische Universität München, D-85747 Garching, Germany, and Department of Medicinal Chemistry and Molecular Pharmacology, School of Pharmacy, Purdue University, West Lafayette, Indiana 47907
| | - Adelbert Bacher
- Contribution from the Department of Chemistry, Washington University, Saint Louis, Missouri 63130, Department of Physics, State University of New York at Binghamton, Binghamton, New York 13902, Lehrstuhl für Organische Chemie und Biochemie, Technische Universität München, D-85747 Garching, Germany, and Department of Medicinal Chemistry and Molecular Pharmacology, School of Pharmacy, Purdue University, West Lafayette, Indiana 47907
| | - Mark Cushman
- Contribution from the Department of Chemistry, Washington University, Saint Louis, Missouri 63130, Department of Physics, State University of New York at Binghamton, Binghamton, New York 13902, Lehrstuhl für Organische Chemie und Biochemie, Technische Universität München, D-85747 Garching, Germany, and Department of Medicinal Chemistry and Molecular Pharmacology, School of Pharmacy, Purdue University, West Lafayette, Indiana 47907
| | - Jacob Schaefer
- Contribution from the Department of Chemistry, Washington University, Saint Louis, Missouri 63130, Department of Physics, State University of New York at Binghamton, Binghamton, New York 13902, Lehrstuhl für Organische Chemie und Biochemie, Technische Universität München, D-85747 Garching, Germany, and Department of Medicinal Chemistry and Molecular Pharmacology, School of Pharmacy, Purdue University, West Lafayette, Indiana 47907
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Abstract
The shikimate pathway links metabolism of carbohydrates to biosynthesis of aromatic compounds. In a sequence of seven metabolic steps, phosphoenolpyruvate and erythrose 4-phosphate are converted to chorismate, the precursor of the aromatic amino acids and many aromatic secondary metabolites. All pathway intermediates can also be considered branch point compounds that may serve as substrates for other metabolic pathways. The shikimate pathway is found only in microorganisms and plants, never in animals. All enzymes of this pathway have been obtained in pure form from prokaryotic and eukaryotic sources and their respective DNAs have been characterized from several organisms. The cDNAs of higher plants encode proteins with amino terminal signal sequences for plastid import, suggesting that plastids are the exclusive locale for chorismate biosynthesis. In microorganisms, the shikimate pathway is regulated by feedback inhibition and by repression of the first enzyme. In higher plants, no physiological feedback inhibitor has been identified, suggesting that pathway regulation may occur exclusively at the genetic level. This difference between microorganisms and plants is reflected in the unusually large variation in the primary structures of the respective first enzymes. Several of the pathway enzymes occur in isoenzymic forms whose expression varies with changing environmental conditions and, within the plant, from organ to organ. The penultimate enzyme of the pathway is the sole target for the herbicide glyphosate. Glyphosate-tolerant transgenic plants are at the core of novel weed control systems for several crop plants.
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Affiliation(s)
- Klaus M. Herrmann
- Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907; e-mail: , Monsanto Company, St. Louis, Missouri 63198; e-mail:
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