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Cuny E, Fohrer J, Klingler FD. Biomimetic Total Synthesis of ( + )-Ranuncoside, a Unique Tricyclic Spiroacetal Glycoside of Christmas Rose ( Helleborus niger L.). Nat Prod Commun 2023. [DOI: 10.1177/1934578x221145919] [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: 12/29/2022] Open
Abstract
Christmas Rose ( Helleborus niger L.) is an alpine plant belonging to the Ranunculaceae family. Typical for this popular ornamental plant are white flowers that appear during winter. Root extracts contain numerous medicinally active ingredients and potent cardiac glycosides. Recent findings indicate that Helleborus root extracts possess the potential for cancer treatment and inhibit the proliferation of tumor cells. In 2022, we published a practical extraction method of ( + )-ranucoside 1 from the dried leaves of H niger L. Here, we describe for the first time the total synthesis of 1. Starting from 5-hydroxylevulinic acid methyl ester 8 and acetobromo-α-D-glucose 13, the β-glycoside 14 is formed stereoselectively on the application of Koenigs-Knorr conditions. Subsequent cleavage of the acetyl-protecting groups and saponification of the ester function yields the pyrano dioxane derivative 17. Its lactonization gives ( + )-ranuncoside 1. The presented synthesis is practical and very efficient, consisting of 6 steps from D-glucose and giving 22% overall yield. Furthermore, it is biomimetic due to its concordance with the biosynthesis of ( + )-ranuncoside 1 in H foetidus.
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Affiliation(s)
- Eckehard Cuny
- Clemens-Schöpf-Institute of Organic Chemistry and Biochemistry, Darmstadt Technical University, Darmstadt, Germany
| | - Jörg Fohrer
- Clemens-Schöpf-Institute of Organic Chemistry and Biochemistry, Darmstadt Technical University, Darmstadt, Germany
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2
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Nikolaiczyk V, Irwan J, Nguyen T, Fohrer J, Elbers P, Schrank P, Davari M, Kirschning A. Rational reprogramming of the sesquiterpene synthase BcBOT2 yields new terpenes with presilphiperfolane skeleton. Catal Sci Technol 2022. [DOI: 10.1039/d2cy01617f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Computer-aided rational design of the substrate binding pocket of sesquiterpene synthases BcBOT2 from Botrytis cinerea yielded FPP cyclization products with presilphiperfolane backbone other than the naturally formed sesquiterpene presilphiperfolan-8β-ol. Particularly,...
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3
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Rai A, Klare JP, Reinke PYA, Englmaier F, Fohrer J, Fedorov R, Taft MH, Chizhov I, Curth U, Plettenburg O, Manstein DJ. Structural and Biochemical Characterization of a Dye-Decolorizing Peroxidase from Dictyostelium discoideum. Int J Mol Sci 2021; 22:ijms22126265. [PMID: 34200865 PMCID: PMC8230527 DOI: 10.3390/ijms22126265] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Revised: 05/29/2021] [Accepted: 06/05/2021] [Indexed: 12/23/2022] Open
Abstract
A novel cytoplasmic dye-decolorizing peroxidase from Dictyostelium discoideum was investigated that oxidizes anthraquinone dyes, lignin model compounds, and general peroxidase substrates such as ABTS efficiently. Unlike related enzymes, an aspartate residue replaces the first glycine of the conserved GXXDG motif in Dictyostelium DyPA. In solution, Dictyostelium DyPA exists as a stable dimer with the side chain of Asp146 contributing to the stabilization of the dimer interface by extending the hydrogen bond network connecting two monomers. To gain mechanistic insights, we solved the Dictyostelium DyPA structures in the absence of substrate as well as in the presence of potassium cyanide and veratryl alcohol to 1.7, 1.85, and 1.6 Å resolution, respectively. The active site of Dictyostelium DyPA has a hexa-coordinated heme iron with a histidine residue at the proximal axial position and either an activated oxygen or CN- molecule at the distal axial position. Asp149 is in an optimal conformation to accept a proton from H2O2 during the formation of compound I. Two potential distal solvent channels and a conserved shallow pocket leading to the heme molecule were found in Dictyostelium DyPA. Further, we identified two substrate-binding pockets per monomer in Dictyostelium DyPA at the dimer interface. Long-range electron transfer pathways associated with a hydrogen-bonding network that connects the substrate-binding sites with the heme moiety are described.
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Affiliation(s)
- Amrita Rai
- Institute for Biophysical Chemistry, Hannover Medical School, Fritz Hartmann Centre for Medical Research Carl Neuberg Str. 1, D-30625 Hannover, Germany; (A.R.); (P.Y.A.R.); (M.H.T.); (I.C.); (U.C.)
- Department of Structural Biochemistry, Max Planck Institute of Molecular Physiology, D-44227 Dortmund, Germany
| | - Johann P. Klare
- Department of Physics, University of Osnabrueck, Barbarastrasse 7, D-49076 Osnabrück, Germany;
| | - Patrick Y. A. Reinke
- Institute for Biophysical Chemistry, Hannover Medical School, Fritz Hartmann Centre for Medical Research Carl Neuberg Str. 1, D-30625 Hannover, Germany; (A.R.); (P.Y.A.R.); (M.H.T.); (I.C.); (U.C.)
- Division for Structural Biochemistry, Hannover Medical School, Carl Neuberg Str. 1, D-30625 Hannover, Germany;
- Center for Free-Electron Laser Science, German Electron Synchrotron (DESY), Notkestr. 85, D-22607 Hamburg, Germany
| | - Felix Englmaier
- Institute of Medicinal Chemistry, Helmholtz Zentrum München (GmbH), German Research Center for Environmental Health, Ingolstädter Landstraße 1, D-85764 Neuherberg, Germany; (F.E.); (O.P.)
- Center of Biomolecular Drug Research (BMWZ), Institute of Organic Chemistry, Leibniz University Hannover, Schneiderberg 1b, D-30167 Hannover, Germany;
| | - Jörg Fohrer
- Center of Biomolecular Drug Research (BMWZ), Institute of Organic Chemistry, Leibniz University Hannover, Schneiderberg 1b, D-30167 Hannover, Germany;
- NMR Department of the Department of Chemistry, Technical University Darmstadt, Clemens Schöpf Institute for Organic Chemistry and Biochemistry, Alarich-Weiss-Strasse 4, D-64287 Darmstadt, Germany
| | - Roman Fedorov
- Division for Structural Biochemistry, Hannover Medical School, Carl Neuberg Str. 1, D-30625 Hannover, Germany;
| | - Manuel H. Taft
- Institute for Biophysical Chemistry, Hannover Medical School, Fritz Hartmann Centre for Medical Research Carl Neuberg Str. 1, D-30625 Hannover, Germany; (A.R.); (P.Y.A.R.); (M.H.T.); (I.C.); (U.C.)
| | - Igor Chizhov
- Institute for Biophysical Chemistry, Hannover Medical School, Fritz Hartmann Centre for Medical Research Carl Neuberg Str. 1, D-30625 Hannover, Germany; (A.R.); (P.Y.A.R.); (M.H.T.); (I.C.); (U.C.)
- Division for Structural Biochemistry, Hannover Medical School, Carl Neuberg Str. 1, D-30625 Hannover, Germany;
| | - Ute Curth
- Institute for Biophysical Chemistry, Hannover Medical School, Fritz Hartmann Centre for Medical Research Carl Neuberg Str. 1, D-30625 Hannover, Germany; (A.R.); (P.Y.A.R.); (M.H.T.); (I.C.); (U.C.)
- Division for Structural Biochemistry, Hannover Medical School, Carl Neuberg Str. 1, D-30625 Hannover, Germany;
| | - Oliver Plettenburg
- Institute of Medicinal Chemistry, Helmholtz Zentrum München (GmbH), German Research Center for Environmental Health, Ingolstädter Landstraße 1, D-85764 Neuherberg, Germany; (F.E.); (O.P.)
- Center of Biomolecular Drug Research (BMWZ), Institute of Organic Chemistry, Leibniz University Hannover, Schneiderberg 1b, D-30167 Hannover, Germany;
| | - Dietmar J. Manstein
- Institute for Biophysical Chemistry, Hannover Medical School, Fritz Hartmann Centre for Medical Research Carl Neuberg Str. 1, D-30625 Hannover, Germany; (A.R.); (P.Y.A.R.); (M.H.T.); (I.C.); (U.C.)
- Division for Structural Biochemistry, Hannover Medical School, Carl Neuberg Str. 1, D-30625 Hannover, Germany;
- RESiST, Cluster of Excellence 2155, Medizinische Hochschule Hannover, D-30625 Hannover, Germany
- Correspondence: ; Tel.: +49-511-5323700
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4
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Rottmann E, Volkmann K, Fohrer J, Krings U, Berger RG. Phenylacrylic acids addition to potato and sweet potato showed no impact on acrylamide concentration via oxa-Michael-addition during frying. Curr Res Food Sci 2021; 4:262-269. [PMID: 33982009 PMCID: PMC8085776 DOI: 10.1016/j.crfs.2021.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 04/06/2021] [Accepted: 04/08/2021] [Indexed: 11/04/2022] Open
Abstract
Three phenolic acids, p-coumaric, ferulic and caffeic acid as well as cinnamic acid were added to raw potatoes and sweet potatoes before frying. A distinct mitigation of acrylamide was not detected. Fried samples were analysed for postulated adducts of a direct reaction between acrylamide and these phenolic acids using LC-MS. In a model system with pure compounds (phenylacrylic acid and acrylamide) heated on 10% hydrated silica gel one specific adduct (respective m/z for M + H+) was formed in each reaction. MS/MS-data suggested an oxa-Michael formation of 3-amino-3-oxopropyl-phenylacrylates, which was confirmed by de novo syntheses along an SN2 substitution of 3-chloropropanamide. Exemplarily, the structure of the ester was confirmed for p-coumaric acid by NMR-data. Standard addition revealed that 3-amino-(3-oxopropyl-phenyl)-acrylates occurred neither in fried potato nor in sweet potato, while a formation was shown in phenylacrylic acid plus acrylamide supplemented potatoes and sweet potatoes. Reaction pathways of phenylacrylic acids with acrylamide elucidated. Esterification of p-coumaric acid with 3-chloropropanamide. Identification of 3-amino-3-oxopropyl-3-(4-hydroxyphenyl)acrylate. Explanation of the low mitigation impact of phenylacrylic acids.
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Affiliation(s)
- Eric Rottmann
- Gottfried Wilhelm Leibniz Universität Hannover, Institut für Lebensmittelchemie, Callinstraße 5, 30167, Hannover, Germany
| | - Kristina Volkmann
- Gottfried Wilhelm Leibniz Universität Hannover, Institut für Lebensmittelchemie, Callinstraße 5, 30167, Hannover, Germany
| | - Jörg Fohrer
- Gottfried Wilhelm Leibniz Universität Hannover, Institut für Organische Chemie, Schneiderberg 1B, 30167, Hannover, Germany
| | - Ulrich Krings
- Gottfried Wilhelm Leibniz Universität Hannover, Institut für Lebensmittelchemie, Callinstraße 5, 30167, Hannover, Germany
| | - Ralf G Berger
- Gottfried Wilhelm Leibniz Universität Hannover, Institut für Lebensmittelchemie, Callinstraße 5, 30167, Hannover, Germany
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5
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Bartling B, Brüchle NC, Rehfeld JS, Boßmann D, Fiebig T, Litschko C, Fohrer J, Gerardy-Schahn R, Scheper T, Beutel S. Accelerated production of α2,8- and α2,9-linked polysialic acid in recombinant Escherichia coli using high cell density cultivation. Biotechnol Rep (Amst) 2020; 28:e00562. [PMID: 33304838 PMCID: PMC7711218 DOI: 10.1016/j.btre.2020.e00562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 10/05/2020] [Accepted: 11/17/2020] [Indexed: 11/29/2022]
Abstract
Polysialic acid (polySia) are α2,8- and/or α2,9-linked homopolymers with interesting properties for meningococcal vaccine development or the cure of human neurodegenerative disorders. With the goal to avoid large scale production of pathogenic bacteria, we compare in the current study the efficacy of conventional polySia production to recombinant approaches using the engineered laboratory safety strain E. coli BL21. High cell density cultivation (HCDC) experiments were performed in two different bioreactor systems. Increased cell densities of up to 11.3 (±0.4) g/L and polySia concentrations of up to 774 (±18) mg/L were reached in E. coli K1. However, cultivation of engineered E. coli BL21 strains delivered comparable cell densities but a maximum of only 133 mg/L polySia. Using established downstream procedures, host cell DNA and proteins were removed. All recombinant polySia products showed an identical degree of polymerization >90. Polymers with different glycosidic linkages could be successfully differentiated by nuclear magnetic resonance spectroscopy.
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Affiliation(s)
- Bastian Bartling
- Institute of Technical Chemistry, Leibniz University Hannover, D-30167 Hannover, Germany
| | - Nora C. Brüchle
- Institute of Technical Chemistry, Leibniz University Hannover, D-30167 Hannover, Germany
| | - Johanna S. Rehfeld
- Institute of Technical Chemistry, Leibniz University Hannover, D-30167 Hannover, Germany
| | - Daniel Boßmann
- Institute of Technical Chemistry, Leibniz University Hannover, D-30167 Hannover, Germany
| | - Timm Fiebig
- Institute of Clinical Biochemistry, Hannover Medical School, D-30625 Hannover, Germany
| | - Christa Litschko
- Institute of Clinical Biochemistry, Hannover Medical School, D-30625 Hannover, Germany
| | - Jörg Fohrer
- Institute of Organic Chemistry, Leibniz University Hannover, D-30167 Hannover, Germany
| | - Rita Gerardy-Schahn
- Institute of Clinical Biochemistry, Hannover Medical School, D-30625 Hannover, Germany
| | - Thomas Scheper
- Institute of Technical Chemistry, Leibniz University Hannover, D-30167 Hannover, Germany
| | - Sascha Beutel
- Institute of Technical Chemistry, Leibniz University Hannover, D-30167 Hannover, Germany
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6
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Grosse M, Pendzialeck T, Fohrer J, Berger RG, Krings U. (5 E/ Z,7 E,9)-Decatrien-2-ones, Pineapple-like Flavors from Fomitopsis betulina-Structure Elucidation and Sensorial Properties. J Agric Food Chem 2020; 68:10329-10335. [PMID: 31763832 DOI: 10.1021/acs.jafc.9b06105] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
During the cultivation of the edible mushroom Fomitopsis betulina on agro-industrial side streams, a pleasant flavor strongly reminiscent of pineapple was perceived. Aroma extract dilution analyses identified two flavor components with a distinct pineapple odor. On the basis of mass spectrometric data, a Wittig reaction of (E)-penta-2,4-dien-1-yltriphosphonium bromide with ethyl levulinate was conducted. The resulting (5E/Z,7E,9)-decatrien-2-ones were identical to the compounds isolated from the fungal culture. Some structurally related methyl ketones were synthesized, confirmed by nuclear magnetic resonance and mass spectrometry, and their odor was characterized. The lowest odor threshold and most characteristic pineapple-like odor was found for (5Z,7E,9)-decatrien-2-one. Global minimum energy calculation of the methyl ketones and the comparison to (1,3E,5Z)-undecatriene, a character impact compound of fresh pineapple, showed that a chain length of at least 10 carbon atoms and a terminal double bond embedded in a "L"-shaped conformation were common to compounds imparting an intense pineapple-like odor. Both (5E/Z,7E,9)-decatrien-2-ones have not been described as natural flavor compounds.
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Affiliation(s)
- Miriam Grosse
- Institute of Food Chemistry, Gottfried Wilhelm Leibniz University, Callinstraße 5, 30167 Hannover, Germany
| | - Tim Pendzialeck
- Institute of Food Chemistry, Gottfried Wilhelm Leibniz University, Callinstraße 5, 30167 Hannover, Germany
| | - Jörg Fohrer
- Institute of Organic Chemistry, Gottfried Wilhelm Leibniz University, Schneiderberg 1B, 30167 Hannover, Germany
| | - Ralf G Berger
- Institute of Food Chemistry, Gottfried Wilhelm Leibniz University, Callinstraße 5, 30167 Hannover, Germany
| | - Ulrich Krings
- Institute of Food Chemistry, Gottfried Wilhelm Leibniz University, Callinstraße 5, 30167 Hannover, Germany
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7
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Kostka T, Fohrer J, Guigas C, Briviba K, Seiwert N, Fahrer J, Steinberg P, Empl MT. Synthesis and in vitro characterization of the genotoxic, mutagenic and cell-transforming potential of nitrosylated heme. Arch Toxicol 2020; 94:3911-3927. [PMID: 32671443 PMCID: PMC7603461 DOI: 10.1007/s00204-020-02846-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 07/09/2020] [Indexed: 12/18/2022]
Abstract
Data from epidemiological studies suggest that consumption of red and processed meat is a factor contributing to colorectal carcinogenesis. Red meat contains high amounts of heme, which in turn can be converted to its nitrosylated form, NO-heme, when adding nitrite-containing curing salt to meat. NO-heme might contribute to colorectal cancer formation by causing gene mutations and could thereby be responsible for the association of (processed) red meat consumption with intestinal cancer. Up to now, neither in vitro nor in vivo studies characterizing the mutagenic and cell transforming potential of NO-heme have been published due to the fact that the pure compound is not readily available. Therefore, in the present study, an already existing synthesis protocol was modified to yield, for the first time, purified NO-heme. Thereafter, newly synthesized NO-heme was chemically characterized and used in various in vitro approaches at dietary concentrations to determine whether it can lead to DNA damage and malignant cell transformation. While NO-heme led to a significant dose-dependent increase in the number of DNA strand breaks in the comet assay and was mutagenic in the HPRT assay, this compound tested negative in the Ames test and failed to induce malignant cell transformation in the BALB/c 3T3 cell transformation assay. Interestingly, the non-nitrosylated heme control showed similar effects, but was additionally able to induce malignant transformation in BALB/c 3T3 murine fibroblasts. Taken together, these results suggest that it is the heme molecule rather than the NO moiety which is involved in driving red meat-associated carcinogenesis.
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Affiliation(s)
- Tina Kostka
- Institute for Food Toxicology, University of Veterinary Medicine Hannover, Hannover, Germany.
- Institute of Food Science and Human Nutrition, Leibniz University Hannover, Hannover, Germany.
| | - Jörg Fohrer
- Institute of Organic Chemistry, Leibniz University Hannover, Hannover, Germany
| | - Claudia Guigas
- Max Rubner-Institut, Federal Research Institute of Nutrition and Food, Karlsruhe, Germany
| | - Karlis Briviba
- Max Rubner-Institut, Federal Research Institute of Nutrition and Food, Karlsruhe, Germany
| | - Nina Seiwert
- Division of Food Chemistry and Toxicology, Department of Chemistry, Technical University of Kaiserslautern, Kaiserslautern, Germany
| | - Jörg Fahrer
- Division of Food Chemistry and Toxicology, Department of Chemistry, Technical University of Kaiserslautern, Kaiserslautern, Germany
| | - Pablo Steinberg
- Institute for Food Toxicology, University of Veterinary Medicine Hannover, Hannover, Germany
- Max Rubner-Institut, Federal Research Institute of Nutrition and Food, Karlsruhe, Germany
| | - Michael T Empl
- Institute for Food Toxicology, University of Veterinary Medicine Hannover, Hannover, Germany
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Ekramzadeh K, Brämer C, Frister T, Fohrer J, Kirschning A, Scheper T, Beutel S. Optimization of factors influencing enzyme activity and product selectivity and the role of proton transfer in the catalytic mechanism of patchoulol synthase. Biotechnol Prog 2020; 36:e2935. [DOI: 10.1002/btpr.2935] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 10/07/2019] [Accepted: 10/17/2019] [Indexed: 02/03/2023]
Affiliation(s)
| | | | | | - Jörg Fohrer
- Institute of Organic Chemistry Hanover Germany
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Bartling B, Rehfeld JS, Boßmann D, de Vries I, Fohrer J, Lammers F, Scheper T, Beutel S. Determination of the Structural Integrity and Stability of Polysialic Acid during Alkaline and Thermal Treatment. Molecules 2019; 25:E165. [PMID: 31906121 PMCID: PMC6982714 DOI: 10.3390/molecules25010165] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 12/19/2019] [Accepted: 12/21/2019] [Indexed: 11/16/2022] Open
Abstract
Polysialic acid (polySia) is a linear homopolymer of varying chain lengths that exists mostly on the outer cell membrane surface of certain bacteria, such as Escherichia coli (E. coli) K1. PolySia, with an average degree of polymerization of 20 (polySia avDP20), possesses material properties that can be used for therapeutic applications to treat inflammatory neurodegenerative diseases. The fermentation of E. coli K1 enables the large-scale production of endogenous long-chain polySia (DP ≈ 130) (LC polySia), from which polySia avDP20 can be manufactured using thermal hydrolysis. To ensure adequate biopharmaceutical quality of the product, the removal of byproducts and contaminants, such as endotoxins, is essential. Recent studies have revealed that the long-term incubation in alkaline sodium hydroxide (NaOH) solutions reduces the endotoxin content down to 3 EU (endotoxin units) per mg, which is in the range of pharmaceutical applications. In this study, we analyzed interferences in the intramolecular structure of polySia caused by harsh NaOH treatment or thermal hydrolysis. Nuclear magnetic resonance (NMR) spectroscopy revealed that neither the incubation in an alkaline solution nor the thermal hydrolysis induced any chemical modification. In addition, HPLC analysis with a preceding 1,2-diamino-4,5-methylenedioxybenzene (DMB) derivatization demonstrated that the alkaline treatment did not induce any hydrolytic effects to reduce the maximum polymer length and that the controlled thermal hydrolysis reduced the maximum chain length effectively, while cost-effective incubation in alkaline solutions had no adverse effects on LC polySia. Therefore, both methods guarantee the production of high-purity, low-molecular-weight polySia without alterations in the structure, which is a prerequisite for the submission of a marketing authorization application as a medicinal product. However, a specific synthesis of low-molecular-weight polySia with defined chain lengths is only possible to a limited extent.
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Affiliation(s)
- Bastian Bartling
- Institute of Technical Chemistry, Leibniz University Hannover, 30167 Hannover, Germany; (B.B.); (J.S.R.); (D.B.); (I.d.V.); (T.S.)
| | - Johanna S. Rehfeld
- Institute of Technical Chemistry, Leibniz University Hannover, 30167 Hannover, Germany; (B.B.); (J.S.R.); (D.B.); (I.d.V.); (T.S.)
| | - Daniel Boßmann
- Institute of Technical Chemistry, Leibniz University Hannover, 30167 Hannover, Germany; (B.B.); (J.S.R.); (D.B.); (I.d.V.); (T.S.)
| | - Ingo de Vries
- Institute of Technical Chemistry, Leibniz University Hannover, 30167 Hannover, Germany; (B.B.); (J.S.R.); (D.B.); (I.d.V.); (T.S.)
| | - Jörg Fohrer
- Institute of Organic Chemistry, Leibniz University Hannover, 30167 Hannover, Germany;
| | - Frank Lammers
- Sanofi-Aventis Deutschland GmbH, Industriepark Hoechst, 65929 Frankfurt am Main, Germany;
| | - Thomas Scheper
- Institute of Technical Chemistry, Leibniz University Hannover, 30167 Hannover, Germany; (B.B.); (J.S.R.); (D.B.); (I.d.V.); (T.S.)
| | - Sascha Beutel
- Institute of Technical Chemistry, Leibniz University Hannover, 30167 Hannover, Germany; (B.B.); (J.S.R.); (D.B.); (I.d.V.); (T.S.)
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10
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Glasenapp Y, Lucas C, Wöltje T, Fohrer J, Papenbrock J. Anti-Adhesion Activity of Tannins Isolated from the Mangrove Laguncularia racemosa. Chem Biodivers 2019; 16:e1800632. [PMID: 30835942 DOI: 10.1002/cbdv.201800632] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 03/05/2019] [Indexed: 11/09/2022]
Abstract
In the search of new compounds with biofilm-inhibiting properties, mangroves with their richness of secondary metabolites can be a valuable resource. Crude methanolic leaf extracts from the mangrove Laguncularia racemosa enriched in phenolic substances cause a reduction in initial cell adhesion of Candida glabrata and Candida albicans, but not on Escherichia coli. LC/MS-guided fractionation of the phenolic compounds resulted in 19 fractions, of which ten were analyzed for their bioactivity against cell adhesion. Effects on cell adhesion and planktonic growth of Escherichia coli, Candida glabrata and Candida albicans were measured in 96-well microtiter plates in the presence of 0.2 mg ml-1 of the isolated fractions. Two fractions caused a reduction of cell adhesion of Candida albicans. These fractions containing bioactive compounds were analyzed by LC/MS and NMR spectroscopy. Casuarinin and digalloyl-hexahydroxydiphenoyl-glucose were identified in the active fractions, in addition to three signals of ellagitannins. These results indicate a specific mode of action of hydrolysable tannins against cell adhesion of Candida albicans, which needs to be further analyzed.
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Affiliation(s)
- Yvana Glasenapp
- Institute of Botany, Leibniz University Hannover, Herrenhäuserstrasse 2, D-30419, Hannover, Germany
| | - Christina Lucas
- CECAD Lipidomics Facility, CECAD Research Center, University of Cologne, Joseph-Stelzmann-Strasse 26, D-50931, Köln, Germany
| | - Timo Wöltje
- Institute of Botany, Leibniz University Hannover, Herrenhäuserstrasse 2, D-30419, Hannover, Germany
| | - Jörg Fohrer
- Institute of Organic Chemistry, Leibniz University Hannover, Schneiderberg 1B, D-30167, Hannover, Germany
| | - Jutta Papenbrock
- Institute of Botany, Leibniz University Hannover, Herrenhäuserstrasse 2, D-30419, Hannover, Germany
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11
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Planke T, Moreno M, Hüttel S, Fohrer J, Gille F, Norris MD, Siebke M, Wang L, Müller R, Kirschning A. Cystobactamids 920-1 and 920-2: Assignment of the Constitution and Relative Configuration by Total Synthesis. Org Lett 2019; 21:1359-1363. [DOI: 10.1021/acs.orglett.9b00058] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Therese Planke
- Institut für Organische Chemie und Biomolekulares Wirkstoffzentrum (BMWZ) der Leibniz Universität Hannover, Schneiderberg 1B, 30167 Hannover, Germany
| | - María Moreno
- Institut für Organische Chemie und Biomolekulares Wirkstoffzentrum (BMWZ) der Leibniz Universität Hannover, Schneiderberg 1B, 30167 Hannover, Germany
| | - Stephan Hüttel
- Abteilung Mikrobielle Naturstoffe, Helmholtz Institut für Pharmazeutische Forschung Saarland, Helmholtz Zentrum für Infektionsforschung und Universität des Saarlandes, Campus E8.1, 66123 Saarbrücken, Germany
| | - Jörg Fohrer
- Institut für Organische Chemie und Biomolekulares Wirkstoffzentrum (BMWZ) der Leibniz Universität Hannover, Schneiderberg 1B, 30167 Hannover, Germany
| | - Franziska Gille
- Institut für Organische Chemie und Biomolekulares Wirkstoffzentrum (BMWZ) der Leibniz Universität Hannover, Schneiderberg 1B, 30167 Hannover, Germany
| | - Matthew D. Norris
- Institut für Organische Chemie und Biomolekulares Wirkstoffzentrum (BMWZ) der Leibniz Universität Hannover, Schneiderberg 1B, 30167 Hannover, Germany
| | - Maik Siebke
- Institut für Organische Chemie und Biomolekulares Wirkstoffzentrum (BMWZ) der Leibniz Universität Hannover, Schneiderberg 1B, 30167 Hannover, Germany
| | - Liangliang Wang
- Institut für Organische Chemie und Biomolekulares Wirkstoffzentrum (BMWZ) der Leibniz Universität Hannover, Schneiderberg 1B, 30167 Hannover, Germany
| | - Rolf Müller
- Abteilung Mikrobielle Naturstoffe, Helmholtz Institut für Pharmazeutische Forschung Saarland, Helmholtz Zentrum für Infektionsforschung und Universität des Saarlandes, Campus E8.1, 66123 Saarbrücken, Germany
| | - Andreas Kirschning
- Institut für Organische Chemie und Biomolekulares Wirkstoffzentrum (BMWZ) der Leibniz Universität Hannover, Schneiderberg 1B, 30167 Hannover, Germany
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12
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Abdelhamid IA, Abdelmoniem AM, Fohrer J, Bardenhorst I, Wartchow R, Butenschön H. Dianionic Oxy-Cope Rearrangement with Benzil Derivatives: meso
-Selective 3,3-Coupling of Two Tetrahydrofuran Moieties. European J Org Chem 2017. [DOI: 10.1002/ejoc.201701397] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Ismail Abdelshafy Abdelhamid
- Institut für Organische Chemie; Leibniz Universität Hannover; Schneiderberg 1B 30167 Hannover Germany
- Department of Chemistry; Faculty of Science; Cairo University; 12613 Giza A. R. Egypt
| | - Amr Mohamed Abdelmoniem
- Institut für Organische Chemie; Leibniz Universität Hannover; Schneiderberg 1B 30167 Hannover Germany
- Department of Chemistry; Faculty of Science; Cairo University; 12613 Giza A. R. Egypt
| | - Jörg Fohrer
- Institut für Organische Chemie; Leibniz Universität Hannover; Schneiderberg 1B 30167 Hannover Germany
| | - Iris Bardenhorst
- Institut für Organische Chemie; Leibniz Universität Hannover; Schneiderberg 1B 30167 Hannover Germany
| | - Rudolf Wartchow
- Institut für Anorganische Chemie; Leibniz Universität Hannover; Callinstraße 9 30167 Hannover Germany
| | - Holger Butenschön
- Institut für Organische Chemie; Leibniz Universität Hannover; Schneiderberg 1B 30167 Hannover Germany
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13
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Naini A, Fohrer J, Kalesse M. The Synthesis of Desepoxy-Isotedanolide - A Potential Biosynthetic Precursor of Tedanolide. European J Org Chem 2015. [DOI: 10.1002/ejoc.201500568] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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14
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Franke J, Bock M, Dehn R, Fohrer J, Mhaske SB, Migliorini A, Kanakis AA, Jansen R, Herrmann J, Müller R, Kirschning A. Total and semi-syntheses of antimicrobial thuggacin derivatives. Chemistry 2015; 21:4272-84. [PMID: 25652819 DOI: 10.1002/chem.201405874] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Indexed: 12/26/2022]
Abstract
The total and semi-synthesis of 13 new macrolactones derived from thuggacin, which is a secondary metabolite from the myxobacterium Sorangium cellulosum, are reported. The thuggacins have attracted much attention due to their strong antibacterial activity, particularly towards Mycobacterium tuberculosis. This study focuses on 1) thuggacin derivatives that cannot equilibrate by transacylation between the three natural thuggacins A-C, 2) the roles of the thiazole ring, and 3) the hexyl side chain at C2. Semi-synthetic O-methylation at C17 suppressed the transacylations without a substantial loss of antibacterial activity. Exchanging the C17-C25 side chain for simplified hydrophobic chains led to complete loss of antibacterial activity. Exchange of the thiazole by an oxazole ring or removal of the hexyl side chain at C2 had no substantial effect on the biological properties.
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Affiliation(s)
- Jana Franke
- Institute of Organic Chemistry and Center of Biomolecular Drug Research (BMWZ), Leibniz Universität Hannover, Schneiderberg 1B, 30167 Hannover (Germany), Fax: (+49) 511-762-3011
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15
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Mancuso L, Jürjens G, Hermane J, Harmrolfs K, Eichner S, Fohrer J, Collisi W, Sasse F, Kirschning A. Bioreduction of aryl azides during mutasynthesis of new ansamitocins. Org Lett 2013; 15:4442-5. [PMID: 23981134 DOI: 10.1021/ol401989e] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Supplementing a culture of a mutant strain of Actinosynnema pretiosum that is unable to biosynthesize aminohydroxy benzoic acid (AHBA), with 3-azido-5-hydroxy-benzoic acid and 3-azido-5-amino-benzoic acid, unexpectedly yielded anilino ansamitocins instead of the expected azido derivatives. This is the first example of the bioreduction of organic azides. The unique nature of these results was demonstrated when 3-azido-5-amino-benzoic acid was fed to the corresponding AHBA blocked mutant of Streptomyces hygroscopicus, the geldanamycin producer. This mutasynthetic experiment yielded the fully processed azido derivative of geldanamycin.
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Affiliation(s)
- Lena Mancuso
- Institut für Organische Chemie und Biomolekulares Wikstoffzentrum (BMWZ) der Leibniz Universität Hannover, Schneiderberg 1B, 30167 Hannover, Germany
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16
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Irschik H, Washausen P, Sasse F, Fohrer J, Huch V, Müller R, Prusov EV. Isolierung, Strukturaufklärung und biologische Untersuchung von Maltepoliden: bemerkenswerte Makrolide aus Myxobakterien. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201210113] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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17
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Irschik H, Washausen P, Sasse F, Fohrer J, Huch V, Müller R, Prusov EV. Isolation, Structure Elucidation, and Biological Activity of Maltepolides: Remarkable Macrolides from Myxobacteria. Angew Chem Int Ed Engl 2013; 52:5402-5. [DOI: 10.1002/anie.201210113] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Indexed: 11/12/2022]
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18
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Carlomagno T, Amata I, Codutti L, Falb M, Fohrer J, Masiewicz P, Simon B. Structural principles of RNA catalysis in a 2'-5' lariat-forming ribozyme. J Am Chem Soc 2013; 135:4403-11. [PMID: 23472843 DOI: 10.1021/ja311868t] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
RNA-catalyzed lariat formation is present in both eukaryotes and prokaryotes. To date we lack structural insights into the catalytic mechanism of lariat-forming ribozymes. Here, we study an artificial 2'-5' AG1 lariat-forming ribozyme that shares the sequence specificity of lariat formation with the pre-mRNA splicing reaction. Using NMR, we solve the structure of the inactive state of the ribozyme in the absence of magnesium. The reaction center 5'-guanosine appears to be part of a helix with an exceptionally widened major groove, while the lariat-forming A48 is looped out at the apex of a pseudoknot. The model of the active state built by mutational analysis, molecular modeling, and small-angle X-ray scattering suggests that A48 is recognized by a conserved adenosine, juxtaposed to the 5'-guanosine in one base-pair step distance, while the G1-N7 coordinates a magnesium ion essential for the activation of the nucleophile. Our findings offer implications for lariat formation in RNA enzymes including the mechanism of the recognition of the branch-site adenosine.
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Affiliation(s)
- Teresa Carlomagno
- Structural and Computational Biology Unit, EMBL, Meyerhofstraße 1, D-69117 Heidelberg, Germany.
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19
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Eichner S, Eichner T, Floss HG, Fohrer J, Hofer E, Sasse F, Zeilinger C, Kirschning A. Broad substrate specificity of the amide synthase in S. hygroscopicus--new 20-membered macrolactones derived from geldanamycin. J Am Chem Soc 2012; 134:1673-9. [PMID: 22136518 DOI: 10.1021/ja2087147] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The amide synthase of the geldanamycin producer, Streptomyces hygroscopicus, shows a broader chemoselectivity than the corresponding amide synthase present in Actinosynnema pretiosum, the producer of the highly cytotoxic ansamycin antibiotics, the ansamitocins. This was demonstrated when blocked mutants of both strains incapable of biosynthesizing 3-amino-5-hydroxybenzoic acid (AHBA), the polyketide synthase starter unit of both natural products, were supplemented with 3-amino-5-hydroxymethylbenzoic acid instead. Unlike the ansamitocin producer A. pretiosum, S. hygroscopicus processed this modified starter unit not only to the expected 19-membered macrolactams but also to ring enlarged 20-membered macrolactones. The former mutaproducts revealed the sequence of transformations catalyzed by the post-PKS tailoring enzymes in geldanamycin biosynthesis. The unprecedented formation of the macrolactones together with molecular modeling studies shed light on the mode of action of the amide synthase responsible for macrocyclization. Obviously, the 3-hydroxymethyl substituent shows similar reactivity and accessibility toward C-1 of the seco-acid as the arylamino group, while phenolic hydroxyl groups lack this propensity to act as nucleophiles in the macrocyclization. The promiscuity of the amide synthase of S. hygroscopicus was further demonstrated by successful feeding of four other m-hydroxymethylbenzoic acids, leading to formation of the expected 20-membered macrocycles. Good to moderate antiproliferative activities were encountered for three of the five new geldanamycin derivatives, which matched well with a competition assay for Hsp90α.
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Affiliation(s)
- Simone Eichner
- Institute of Organic Chemistry and Center of Biomolecular Research (BMWZ), Schneiderberg 1B, Leibniz University Hannover, D-30167 Hannover, Germany
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20
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Eichner S, Knobloch T, Floss HG, Fohrer J, Harmrolfs K, Hermane J, Schulz A, Sasse F, Spiteller P, Taft F, Kirschning A. The interplay between mutasynthesis and semisynthesis: generation and evaluation of an ansamitocin library. Angew Chem Int Ed Engl 2011; 51:752-7. [PMID: 22135226 DOI: 10.1002/anie.201106249] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2011] [Indexed: 12/20/2022]
Affiliation(s)
- Simone Eichner
- Institut für Organische Chemie und Biomolekulares Wirkstoffzentrum (BMWZ), Leibniz Universität Hannover, Schneiderberg 1B, 30167 Hannover, Germany
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21
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Eichner S, Knobloch T, Floss HG, Fohrer J, Harmrolfs K, Hermane J, Schulz A, Sasse F, Spiteller P, Taft F, Kirschning A. The Interplay between Mutasynthesis and Semisynthesis: Generation and Evaluation of an Ansamitocin Library. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201106249] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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22
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Bülow L, Naini A, Fohrer J, Kalesse M. A Kiyooka aldol approach for the synthesis of the C(14)-C(23) segment of the diastereomeric analog of tedanolide C. Org Lett 2011; 13:6038-41. [PMID: 22026452 DOI: 10.1021/ol202515x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The challenging synthesis of a quaternary center within the highly oxygenated setting of tedanolide C can be performed via a Kiyooka aldol reaction. Here, the diastereomeric analog of tedanolide C with the configurations between C10 and C20 opposite compared to the proposed structure was chosen as the synthetic target. The tetra-substituted silyl ketene acetal provides the southern hemisphere of tedanolide C in useful selectivities, and the absolute configuration of the newly generated quaternary center was determined by NOE experiments of the corresponding acetonide.
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Affiliation(s)
- Leila Bülow
- Centre for Biomolecular Drug Research, Leibniz Universität Hannover, 30167 Hannover, Germany
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23
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Erdélyi M, Pfeiffer B, Hauenstein K, Fohrer J, Gertsch J, Altmann KH, Carlomagno T. Conformational preferences of natural and C3-modified epothilones in aqueous solution. J Med Chem 2008; 51:1469-73. [PMID: 18271516 DOI: 10.1021/jm7013452] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The conformational properties of the microtubule-stabilizing agent epothilone A ( 1a) and its 3-deoxy and 3-deoxy-2,3-didehydro derivatives 2 and 3 have been investigated in aqueous solution by a combination of NMR spectroscopic methods, Monte Carlo conformational searches, and NAMFIS calculations. The tubulin-bound conformation of epothilone A ( 1a), as previously proposed on the basis of solution NMR data, was found to represent a significant fraction of the ensemble of conformations present for the free ligands in aqueous solution.
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Affiliation(s)
- Máté Erdélyi
- Max-Planck-Institute for Biophysical Chemistry, NMR-Based Structural Biology, Am Fassberg 11, D-37077 Göttingen, Germany
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24
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Fohrer J, Reinscheid U, Hennig M, Carlomagno T. Calculation of the Dependence of Homo- and Heteronuclear3J and2J Scalar Couplings for the Determination of the 2′-Hydroxy Conformation in RNA. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200602583] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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25
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Fohrer J, Reinscheid U, Hennig M, Carlomagno T. Calculation of the Dependence of Homo- and Heteronuclear3J and2J Scalar Couplings for the Determination of the 2′-Hydroxy Conformation in RNA. Angew Chem Int Ed Engl 2006; 45:7033-6. [PMID: 17006869 DOI: 10.1002/anie.200602583] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Jörg Fohrer
- Abteilung 030, Max-Planck-Institut für Biophysikalische Chemie, Am Fassberg 11, 37077 Göttingen, Germany
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26
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Fohrer J, Hennig M, Carlomagno T. Influence of the 2'-hydroxyl group conformation on the stability of A-form helices in RNA. J Mol Biol 2005; 356:280-7. [PMID: 16376377 DOI: 10.1016/j.jmb.2005.11.043] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [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] [Received: 08/24/2005] [Revised: 11/09/2005] [Accepted: 11/14/2005] [Indexed: 11/18/2022]
Abstract
The 2'-hydroxyl group plays fundamental roles in both the structure and the function of RNA, and is the major determinant of the conformational and thermodynamic differences between RNA and DNA. Here, we report a conformational analysis of 2'-OH groups of the HIV-2 TAR RNA by means of NMR scalar coupling measurements in solution. Our analysis supports the existence of a network of water molecules spanning the minor groove of an RNA A-form helix, as has been suggested on the basis of a high-resolution X-ray study of an RNA duplex. The 2'-OH protons of the lower stem nucleotides of the TAR RNA project either towards the O3' or towards the base, where the 2'-OH group can favorably participate in H-bonding interactions with a water molecule situated in the nucleotide base plane. We observe that the k(ex) rate of the 2'-OH proton with the bulk solvent anti-correlates with the base-pair stability, confirming the involvement of the 2'-OH group in a collective network of H-bonds, which requires the presence of canonical helical secondary structure. The methodology and conformational analysis presented here are broadly applicable and facilitate future studies aimed to correlate the conformation of the 2'-OH group with both the structure and the function of RNA and RNA-ligand complexes.
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Affiliation(s)
- Jörg Fohrer
- Department of NMR Based Structural Biology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
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27
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Hennig M, Fohrer J, Carlomagno T. Assignment and NOE analysis of 2'-hydroxyl protons in RNA: implications for stabilization of RNA A-form duplexes. J Am Chem Soc 2005; 127:2028-9. [PMID: 15713064 DOI: 10.1021/ja043390o] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The ribose 2'-OH hydroxyl group distinguishes RNA from DNA. The 2'-OH hydroxyl protons are responsible for differences in conformation, hydration, and thermodynamic stability of RNA and DNA oligonucleotides. Additionally, the 2'-OH group plays a central role in RNA catalysis. This important group lies in the shallow groove of RNA, where it is involved in a network of hydrogen bonds with water molecules stabilizing RNA A-form duplexes. Structural and dynamical information on 2'-OH hydroxyl protons is essential to understand their respective roles. Here we report the 2'-OH hydroxyl proton assignments for a 30mer RNA, the HIV-2 transactivation region, in water using solution NMR techniques. We provide structural information on 2'-OH hydroxyl groups in the form of orientational preferences contradicting the paradigm that the 2'-OH hydroxyl typically points away from the ribose H1' proton.
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Affiliation(s)
- Mirko Hennig
- Department of Molecular Biology, The Scripps Research Institute, MB33, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
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