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Jørgensen ME, Houston K, Jørgensen HJL, Thomsen HC, Tekaat L, Krogh CT, Mellor SB, Braune KB, Damm ML, Pedas PR, Voss C, Rasmussen MW, Nielsen K, Skadhauge B, Motawia MS, Møller BL, Dockter C, Sørensen M. Disentangling hydroxynitrile glucoside biosynthesis in a barley (Hordeum vulgare) metabolon provides access to elite malting barleys for ethyl carbamate-free whisky production. Plant J 2024. [PMID: 38652034 DOI: 10.1111/tpj.16768] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 03/26/2024] [Accepted: 04/02/2024] [Indexed: 04/25/2024]
Abstract
Barley produces several specialized metabolites, including five α-, β-, and γ-hydroxynitrile glucosides (HNGs). In malting barley, presence of the α-HNG epiheterodendrin gives rise to undesired formation of ethyl carbamate in the beverage production, especially after distilling. Metabolite-GWAS identified QTLs and underlying gene candidates possibly involved in the control of the relative and absolute content of HNGs, including an undescribed MATE transporter. By screening 325 genetically diverse barley accessions, we discovered three H. vulgare ssp. spontaneum (wild barley) lines with drastic changes in the relative ratios of the five HNGs. Knock-out (KO)-lines, isolated from the barley FIND-IT resource and each lacking one of the functional HNG biosynthetic genes (CYP79A12, CYP71C103, CYP71C113, CYP71U5, UGT85F22 and UGT85F23) showed unprecedented changes in HNG ratios enabling assignment of specific and mutually dependent catalytic functions to the biosynthetic enzymes involved. The highly similar relative ratios between the five HNGs found across wild and domesticated barley accessions indicate assembly of the HNG biosynthetic enzymes in a metabolon, the functional output of which was reconfigured in the absence of a single protein component. The absence or altered ratios of the five HNGs in the KO-lines did not change susceptibility to the fungal phytopathogen Pyrenophora teres causing net blotch. The study provides a deeper understanding of the organization of HNG biosynthesis in barley and identifies a novel, single gene HNG-0 line in an elite spring barley background for direct use in breeding of malting barley, eliminating HNGs as a source of ethyl carbamate formation in whisky production.
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Affiliation(s)
- Morten E Jørgensen
- Carlsberg Research Laboratory, J.C. Jacobsens Gade 4, DK-1799, Copenhagen V, Denmark
| | - Kelly Houston
- Cell and Molecular Sciences, James Hutton Institute, Errol Road, Invergowrie, Dundee, Scotland
| | - Hans Jørgen L Jørgensen
- Section for Plant and Soil Sciences, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
- Copenhagen Plant Science Centre, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Hanne C Thomsen
- Carlsberg Research Laboratory, J.C. Jacobsens Gade 4, DK-1799, Copenhagen V, Denmark
| | - Linda Tekaat
- Copenhagen Plant Science Centre, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Camilla Timmermann Krogh
- Copenhagen Plant Science Centre, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Silas B Mellor
- Copenhagen Plant Science Centre, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | | | - Mette L Damm
- Carlsberg Research Laboratory, J.C. Jacobsens Gade 4, DK-1799, Copenhagen V, Denmark
| | - Pai Rosager Pedas
- Carlsberg Research Laboratory, J.C. Jacobsens Gade 4, DK-1799, Copenhagen V, Denmark
| | - Cynthia Voss
- Carlsberg Research Laboratory, J.C. Jacobsens Gade 4, DK-1799, Copenhagen V, Denmark
| | | | - Kasper Nielsen
- Carlsberg Research Laboratory, J.C. Jacobsens Gade 4, DK-1799, Copenhagen V, Denmark
| | - Birgitte Skadhauge
- Carlsberg Research Laboratory, J.C. Jacobsens Gade 4, DK-1799, Copenhagen V, Denmark
| | - Mohammed S Motawia
- Copenhagen Plant Science Centre, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Birger Lindberg Møller
- Copenhagen Plant Science Centre, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Christoph Dockter
- Carlsberg Research Laboratory, J.C. Jacobsens Gade 4, DK-1799, Copenhagen V, Denmark
| | - Mette Sørensen
- Copenhagen Plant Science Centre, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
- Novo Nordisk Pharmatech, Københavnsvej 216, 4600, Køge, Denmark
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2
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Zhao Y, Hansen NL, Duan YT, Prasad M, Motawia MS, Møller BL, Pateraki I, Staerk D, Bak S, Miettinen K, Kampranis SC. Biosynthesis and biotechnological production of the anti-obesity agent celastrol. Nat Chem 2023; 15:1236-1246. [PMID: 37365337 DOI: 10.1038/s41557-023-01245-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [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: 09/24/2022] [Accepted: 05/19/2023] [Indexed: 06/28/2023]
Abstract
Obesity is a major health risk still lacking effective pharmacological treatment. A potent anti-obesity agent, celastrol, has been identified in the roots of Tripterygium wilfordii. However, an efficient synthetic method is required to better explore its biological utility. Here we elucidate the 11 missing steps for the celastrol biosynthetic route to enable its de novo biosynthesis in yeast. First, we reveal the cytochrome P450 enzymes that catalyse the four oxidation steps that produce the key intermediate celastrogenic acid. Subsequently, we show that non-enzymatic decarboxylation-triggered activation of celastrogenic acid leads to a cascade of tandem catechol oxidation-driven double-bond extension events that generate the characteristic quinone methide moiety of celastrol. Using this acquired knowledge, we have developed a method for producing celastrol starting from table sugar. This work highlights the effectiveness of combining plant biochemistry with metabolic engineering and chemistry for the scalable synthesis of complex specialized metabolites.
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Affiliation(s)
- Yong Zhao
- Biochemical Engineering Group, Plant Biochemistry Section, Department of Plant and Environment Sciences, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark
| | - Nikolaj L Hansen
- Biochemical Engineering Group, Plant Biochemistry Section, Department of Plant and Environment Sciences, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark
| | - Yao-Tao Duan
- Biochemical Engineering Group, Plant Biochemistry Section, Department of Plant and Environment Sciences, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark
| | - Meera Prasad
- Biochemical Engineering Group, Plant Biochemistry Section, Department of Plant and Environment Sciences, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark
| | - Mohammed S Motawia
- Biochemical Engineering Group, Plant Biochemistry Section, Department of Plant and Environment Sciences, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark
| | - Birger L Møller
- Biochemical Engineering Group, Plant Biochemistry Section, Department of Plant and Environment Sciences, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark
| | - Irini Pateraki
- Biochemical Engineering Group, Plant Biochemistry Section, Department of Plant and Environment Sciences, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark
| | - Dan Staerk
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Søren Bak
- Biochemical Engineering Group, Plant Biochemistry Section, Department of Plant and Environment Sciences, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark.
| | - Karel Miettinen
- Biochemical Engineering Group, Plant Biochemistry Section, Department of Plant and Environment Sciences, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark.
| | - Sotirios C Kampranis
- Biochemical Engineering Group, Plant Biochemistry Section, Department of Plant and Environment Sciences, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark.
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3
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Gülck T, Booth JK, Carvalho Â, Khakimov B, Crocoll C, Motawia MS, Møller BL, Bohlmann J, Gallage NJ. Synthetic Biology of Cannabinoids and Cannabinoid Glucosides in Nicotiana benthamiana and Saccharomyces cerevisiae. J Nat Prod 2020; 83:2877-2893. [PMID: 33000946 DOI: 10.1021/acs.jnatprod.0c00241] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Phytocannabinoids are a group of plant-derived metabolites that display a wide range of psychoactive as well as health-promoting effects. The production of pharmaceutically relevant cannabinoids relies on extraction and purification from cannabis (Cannabis sativa) plants yielding the major constituents, Δ9-tetrahydrocannabinol and cannabidiol. Heterologous biosynthesis of cannabinoids in Nicotiana benthamiana or Saccharomyces cerevisiae may provide cost-efficient and rapid future production platforms to acquire pure and high quantities of both the major and the rare cannabinoids as well as novel derivatives. Here, we used a meta-transcriptomic analysis of cannabis to identify genes for aromatic prenyltransferases of the UbiA superfamily and chalcone isomerase-like (CHIL) proteins. Among the aromatic prenyltransferases, CsaPT4 showed CBGAS activity in both N. benthamiana and S. cerevisiae. Coexpression of selected CsaPT pairs and of CHIL proteins encoding genes with CsaPT4 did not affect CBGAS catalytic efficiency. In a screen of different plant UDP-glycosyltransferases, Stevia rebaudiana SrUGT71E1 and Oryza sativa OsUGT5 were found to glucosylate olivetolic acid, cannabigerolic acid, and Δ9-tetrahydrocannabinolic acid. Metabolic engineering of N. benthamiana for production of cannabinoids revealed intrinsic glucosylation of olivetolic acid and cannabigerolic acid. S. cerevisiae was engineered to produce olivetolic acid glucoside and cannabigerolic acid glucoside.
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Affiliation(s)
- Thies Gülck
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - J K Booth
- Michael Smith Laboratories, University of British Columbia, 2185 East Mall, Vancouver, BC, Canada V6T 1Z4
| | - Â Carvalho
- River Stone Biotech ApS, Fruebjergvej 3, 2100 København Ø, Denmark
| | - B Khakimov
- Chemometrics & Analytical Technology, Department of Food Science, University of Copenhagen, Rolighedsvej 26, 1958 Frederiksberg C, Denmark
| | - C Crocoll
- Copenhagen Plant Science Centre, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - M S Motawia
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - B L Møller
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
- Copenhagen Plant Science Centre, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - J Bohlmann
- Michael Smith Laboratories, University of British Columbia, 2185 East Mall, Vancouver, BC, Canada V6T 1Z4
| | - N J Gallage
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
- Octarine Bio, Fruebjergvej 3, 2100 København Ø, Denmark
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4
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Ignea C, Pontini M, Motawia MS, Maffei ME, Makris AM, Kampranis SC. Synthesis of 11-carbon terpenoids in yeast using protein and metabolic engineering. Nat Chem Biol 2018; 14:1090-1098. [DOI: 10.1038/s41589-018-0166-5] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 10/11/2018] [Indexed: 12/12/2022]
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5
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Del Cueto J, Ionescu IA, Pičmanová M, Gericke O, Motawia MS, Olsen CE, Campoy JA, Dicenta F, Møller BL, Sánchez-Pérez R. Cyanogenic Glucosides and Derivatives in Almond and Sweet Cherry Flower Buds from Dormancy to Flowering. Front Plant Sci 2017; 8:800. [PMID: 28579996 PMCID: PMC5437698 DOI: 10.3389/fpls.2017.00800] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 04/28/2017] [Indexed: 05/07/2023]
Abstract
Almond and sweet cherry are two economically important species of the Prunus genus. They both produce the cyanogenic glucosides prunasin and amygdalin. As part of a two-component defense system, prunasin and amygdalin release toxic hydrogen cyanide upon cell disruption. In this study, we investigated the potential role within prunasin and amygdalin and some of its derivatives in endodormancy release of these two Prunus species. The content of prunasin and of endogenous prunasin turnover products in the course of flower development was examined in five almond cultivars - differing from very early to extra-late in flowering time - and in one sweet early cherry cultivar. In all cultivars, prunasin began to accumulate in the flower buds shortly after dormancy release and the levels dropped again just before flowering time. In almond and sweet cherry, the turnover of prunasin coincided with increased levels of prunasin amide whereas prunasin anitrile pentoside and β-D-glucose-1-benzoate were abundant in almond and cherry flower buds at certain developmental stages. These findings indicate a role for the turnover of cyanogenic glucosides in controlling flower development in Prunus species.
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Affiliation(s)
- Jorge Del Cueto
- Department of Plant Breeding, CEBAS-CSICMurcia, Spain
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of CopenhagenFrederiksberg, Denmark
- VILLUM Research Center for Plant Plasticity, University of CopenhagenFrederiksberg, Denmark
| | - Irina A. Ionescu
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of CopenhagenFrederiksberg, Denmark
- VILLUM Research Center for Plant Plasticity, University of CopenhagenFrederiksberg, Denmark
| | - Martina Pičmanová
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of CopenhagenFrederiksberg, Denmark
- VILLUM Research Center for Plant Plasticity, University of CopenhagenFrederiksberg, Denmark
| | - Oliver Gericke
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of CopenhagenFrederiksberg, Denmark
- VILLUM Research Center for Plant Plasticity, University of CopenhagenFrederiksberg, Denmark
| | - Mohammed S. Motawia
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of CopenhagenFrederiksberg, Denmark
- VILLUM Research Center for Plant Plasticity, University of CopenhagenFrederiksberg, Denmark
| | - Carl E. Olsen
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of CopenhagenFrederiksberg, Denmark
| | - José A. Campoy
- UMR 1332 BFP, INRA, University of BordeauxVillenave d’Ornon, France
| | | | - Birger L. Møller
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of CopenhagenFrederiksberg, Denmark
- VILLUM Research Center for Plant Plasticity, University of CopenhagenFrederiksberg, Denmark
| | - Raquel Sánchez-Pérez
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of CopenhagenFrederiksberg, Denmark
- VILLUM Research Center for Plant Plasticity, University of CopenhagenFrederiksberg, Denmark
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6
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Gray CJ, Schindler B, Migas LG, Pičmanová M, Allouche AR, Green AP, Mandal S, Motawia MS, Sánchez-Pérez R, Bjarnholt N, Møller BL, Rijs AM, Barran PE, Compagnon I, Eyers CE, Flitsch SL. Bottom-Up Elucidation of Glycosidic Bond Stereochemistry. Anal Chem 2017; 89:4540-4549. [PMID: 28350444 DOI: 10.1021/acs.analchem.6b04998] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The lack of robust, high-throughput, and sensitive analytical strategies that can conclusively map the structure of glycans has significantly hampered progress in fundamental and applied aspects of glycoscience. Resolution of the anomeric α/β glycan linkage within oligosaccharides remains a particular challenge. Here, we show that "memory" of anomeric configuration is retained following gas-phase glycosidic bond fragmentation during tandem mass spectrometry (MS2). These findings allow for integration of MS2 with ion mobility spectrometry (IM-MS2) and lead to a strategy to distinguish α- and β-linkages within natural underivatized carbohydrates. We have applied this fragment-based hyphenated MS technology to oligosaccharide standards and to de novo sequencing of purified plant metabolite glycoconjugates, showing that the anomeric signature is also observable in fragments derived from larger glycans. The discovery of the unexpected anomeric memory effect is further supported by IR-MS action spectroscopy and ab initio calculations. Quantum mechanical calculations provide candidate geometries for the distinct anomeric fragment ions, in turn shedding light on gas-phase dissociation mechanisms of glycosidic linkages.
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Affiliation(s)
- Christopher J Gray
- School of Chemistry & Manchester Institute of Biotechnology, The University of Manchester , 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Baptiste Schindler
- Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon 69622 Villeurbanne Cedex, France
| | - Lukasz G Migas
- School of Chemistry & Manchester Institute of Biotechnology, The University of Manchester , 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Martina Pičmanová
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences and Center for Synthetic Biology, University of Copenhagen , 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Abdul R Allouche
- Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon 69622 Villeurbanne Cedex, France
| | - Anthony P Green
- School of Chemistry & Manchester Institute of Biotechnology, The University of Manchester , 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Santanu Mandal
- School of Chemistry & Manchester Institute of Biotechnology, The University of Manchester , 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Mohammed S Motawia
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences and Center for Synthetic Biology, University of Copenhagen , 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Raquel Sánchez-Pérez
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences and Center for Synthetic Biology, University of Copenhagen , 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Nanna Bjarnholt
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences and Center for Synthetic Biology, University of Copenhagen , 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Birger L Møller
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences and Center for Synthetic Biology, University of Copenhagen , 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Anouk M Rijs
- Radboud University , Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7c, 6525ED Nijmegen, The Netherlands
| | - Perdita E Barran
- School of Chemistry & Manchester Institute of Biotechnology, The University of Manchester , 131 Princess Street, Manchester, M1 7DN, United Kingdom.,Michael Barber Centre for Collaborative Mass Spectrometry, Manchester Institute of Biotechnology, The University of Manchester , 131 Princess Street, Manchester, M1 7DN, United Kingdom
| | - Isabelle Compagnon
- Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon 69622 Villeurbanne Cedex, France.,Institut Universitaire de France IUF , 103 Boulevard St. Michel, 75005 Paris, France
| | - Claire E Eyers
- Department of Biochemistry, Institute of Integrative Biology, University of Liverpool , Crown Street, Liverpool, L69 7ZB, United Kingdom
| | - Sabine L Flitsch
- School of Chemistry & Manchester Institute of Biotechnology, The University of Manchester , 131 Princess Street, Manchester, M1 7DN, United Kingdom
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Møller BL, Olsen CE, Motawia MS. General and Stereocontrolled Approach to the Chemical Synthesis of Naturally Occurring Cyanogenic Glucosides. J Nat Prod 2016; 79:1198-202. [PMID: 26959700 DOI: 10.1021/acs.jnatprod.5b01121] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
An effective method for the chemical synthesis of cyanogenic glucosides has been developed as demonstrated by the synthesis of dhurrin, taxiphyllin, prunasin, sambunigrin, heterodendrin, and epiheterodendrin. O-Trimethylsilylated cyanohydrins were prepared and subjected directly to glucosylation using a fully acetylated glucopyranosyl fluoride donor with boron trifluoride-diethyl etherate as promoter to afford a chromatographically separable epimeric mixture of the corresponding acetylated cyanogenic glucosides. The isolated epimers were deprotected using a triflic acid/MeOH/ion-exchange resin system without any epimerization of the cyanohydrin function. The method is stereocontrolled and provides an efficient approach to chemical synthesis of other naturally occurring cyanogenic glucosides including those with a more complex aglycone structure.
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Affiliation(s)
- Birger L Møller
- Carlsberg Laboratory , 10 Gamle Carlsberg Vej, 1799 Copenhagen V, Denmark
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8
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Cuesta-Seijo JA, Nielsen MM, Ruzanski C, Krucewicz K, Beeren SR, Rydhal MG, Yoshimura Y, Striebeck A, Motawia MS, Willats WGT, Palcic MM. In vitro Biochemical Characterization of All Barley Endosperm Starch Synthases. Front Plant Sci 2016; 6:1265. [PMID: 26858729 PMCID: PMC4730117 DOI: 10.3389/fpls.2015.01265] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 12/27/2015] [Indexed: 05/18/2023]
Abstract
Starch is the main storage polysaccharide in cereals and the major source of calories in the human diet. It is synthesized by a panel of enzymes including five classes of starch synthases (SSs). While the overall starch synthase (SS) reaction is known, the functional differences between the five SS classes are poorly understood. Much of our knowledge comes from analyzing mutant plants with altered SS activities, but the resulting data are often difficult to interpret as a result of pleitropic effects, competition between enzymes, overlaps in enzyme activity and disruption of multi-enzyme complexes. Here we provide a detailed biochemical study of the activity of all five classes of SSs in barley endosperm. Each enzyme was produced recombinantly in E. coli and the properties and modes of action in vitro were studied in isolation from other SSs and other substrate modifying activities. Our results define the mode of action of each SS class in unprecedented detail; we analyze their substrate selection, temperature dependence and stability, substrate affinity and temporal abundance during barley development. Our results are at variance with some generally accepted ideas about starch biosynthesis and might lead to the reinterpretation of results obtained in planta. In particular, they indicate that granule bound SS is capable of processive action even in the absence of a starch matrix, that SSI has no elongation limit, and that SSIV, believed to be critical for the initiation of starch granules, has maltoligosaccharides and not polysaccharides as its preferred substrates.
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Affiliation(s)
| | | | | | | | | | - Maja G. Rydhal
- Department of Plant and Environmental Sciences, University of CopenhagenFrederiksberg, Copenhagen, Denmark
| | | | | | - Mohammed S. Motawia
- Department of Plant and Environmental Sciences, University of CopenhagenFrederiksberg, Copenhagen, Denmark
| | - William G. T. Willats
- Department of Plant and Environmental Sciences, University of CopenhagenFrederiksberg, Copenhagen, Denmark
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9
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Frisch T, Motawia MS, Olsen CE, Agerbirk N, Møller BL, Bjarnholt N. Diversified glucosinolate metabolism: biosynthesis of hydrogen cyanide and of the hydroxynitrile glucoside alliarinoside in relation to sinigrin metabolism in Alliaria petiolata. Front Plant Sci 2015; 6:926. [PMID: 26583022 PMCID: PMC4628127 DOI: 10.3389/fpls.2015.00926] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 10/13/2015] [Indexed: 05/06/2023]
Abstract
Alliaria petiolata (garlic mustard, Brassicaceae) contains the glucosinolate sinigrin as well as alliarinoside, a γ-hydroxynitrile glucoside structurally related to cyanogenic glucosides. Sinigrin may defend this plant against a broad range of enemies, while alliarinoside confers resistance to specialized (glucosinolate-adapted) herbivores. Hydroxynitrile glucosides and glucosinolates are two classes of specialized metabolites, which generally do not occur in the same plant species. Administration of [UL-(14)C]-methionine to excised leaves of A. petiolata showed that both alliarinoside and sinigrin were biosynthesized from methionine. The biosynthesis of alliarinoside was shown not to bifurcate from sinigrin biosynthesis at the oxime level in contrast to the general scheme for hydroxynitrile glucoside biosynthesis. Instead, the aglucon of alliarinoside was formed from metabolism of sinigrin in experiments with crude extracts, suggesting a possible biosynthetic pathway in intact cells. Hence, the alliarinoside pathway may represent a route to hydroxynitrile glucoside biosynthesis resulting from convergent evolution. Metabolite profiling by LC-MS showed no evidence of the presence of cyanogenic glucosides in A. petiolata. However, we detected hydrogen cyanide (HCN) release from sinigrin and added thiocyanate ion and benzyl thiocyanate in A. petiolata indicating an enzymatic pathway from glucosinolates via allyl thiocyanate and indole glucosinolate derived thiocyanate ion to HCN. Alliarinoside biosynthesis and HCN release from glucosinolate-derived metabolites expand the range of glucosinolate-related defenses and can be viewed as a third line of defense, with glucosinolates and thiocyanate forming protein being the first and second lines, respectively.
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Affiliation(s)
- Tina Frisch
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of CopenhagenCopenhagen, Denmark
- VILLUM Research Center for Plant Plasticity, Department of Plant and Environmental Sciences, University of CopenhagenCopenhagen, Denmark
| | - Mohammed S. Motawia
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of CopenhagenCopenhagen, Denmark
- VILLUM Research Center for Plant Plasticity, Department of Plant and Environmental Sciences, University of CopenhagenCopenhagen, Denmark
- Center for Synthetic Biology “bioSYNergy”, Department of Plant and Environmental Sciences, University of CopenhagenCopenhagen, Denmark
| | - Carl E. Olsen
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of CopenhagenCopenhagen, Denmark
- VILLUM Research Center for Plant Plasticity, Department of Plant and Environmental Sciences, University of CopenhagenCopenhagen, Denmark
- Center for Synthetic Biology “bioSYNergy”, Department of Plant and Environmental Sciences, University of CopenhagenCopenhagen, Denmark
| | - Niels Agerbirk
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of CopenhagenCopenhagen, Denmark
- Copenhagen Plant Science Center, Department of Plant and Environmental Sciences, University of CopenhagenCopenhagen, Denmark
| | - Birger L. Møller
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of CopenhagenCopenhagen, Denmark
- VILLUM Research Center for Plant Plasticity, Department of Plant and Environmental Sciences, University of CopenhagenCopenhagen, Denmark
- Center for Synthetic Biology “bioSYNergy”, Department of Plant and Environmental Sciences, University of CopenhagenCopenhagen, Denmark
- Copenhagen Plant Science Center, Department of Plant and Environmental Sciences, University of CopenhagenCopenhagen, Denmark
| | - Nanna Bjarnholt
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of CopenhagenCopenhagen, Denmark
- VILLUM Research Center for Plant Plasticity, Department of Plant and Environmental Sciences, University of CopenhagenCopenhagen, Denmark
- Copenhagen Plant Science Center, Department of Plant and Environmental Sciences, University of CopenhagenCopenhagen, Denmark
- *Correspondence: Nanna Bjarnholt
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10
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Kannangara R, Motawia MS, Hansen NKK, Paquette SM, Olsen CE, Møller BL, Jørgensen K. Characterization and expression profile of two UDP-glucosyltransferases, UGT85K4 and UGT85K5, catalyzing the last step in cyanogenic glucoside biosynthesis in cassava. Plant J 2011; 68:287-301. [PMID: 21736650 DOI: 10.1111/j.1365-313x.2011.04695.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Manihot esculenta (cassava) contains two cyanogenic glucosides, linamarin and lotaustralin, biosynthesized from l-valine and l-isoleucine, respectively. In this study, cDNAs encoding two uridine diphosphate glycosyltransferase (UGT) paralogs, assigned the names UGT85K4 and UGT85K5, have been isolated from cassava. The paralogs display 96% amino acid identity, and belong to a family containing cyanogenic glucoside-specific UGTs from Sorghum bicolor and Prunus dulcis. Recombinant UGT85K4 and UGT85K5 produced in Escherichia coli were able to glucosylate acetone cyanohydrin and 2-hydroxy-2-methylbutyronitrile, forming linamarin and lotaustralin. UGT85K4 and UGT85K5 show broad in vitro substrate specificity, as documented by their ability to glucosylate other hydroxynitriles, some flavonoids and simple alcohols. Immunolocalization studies indicated that UGT85K4 and UGT85K5 co-occur with CYP79D1/D2 and CYP71E7 paralogs, which catalyze earlier steps in cyanogenic glucoside synthesis in cassava. These enzymes are all found in mesophyll and xylem parenchyma cells in the first unfolded cassava leaf. In situ PCR showed that UGT85K4 and UGT85K5 are co-expressed with CYP79D1 and both CYP71E7 paralogs in the cortex, xylem and phloem parenchyma, and in specific cells in the endodermis of the petiole of the first unfolded leaf. Based on the data obtained, UGT85K4 and UGT85K5 are concluded to be the UGTs catalyzing in planta synthesis of cyanogenic glucosides. The localization of the biosynthetic enzymes suggests that cyanogenic glucosides may play a role in both defense reactions and in fine-tuning nitrogen assimilation in cassava.
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Affiliation(s)
- Rubini Kannangara
- Plant Biochemistry Laboratory, Department of Plant Biology and Biotechnology, Villum Foundation Research Centre "Pro-Active Plants", UNIK Center for Synthetic Biology, University of Copenhagen, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark
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11
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Takos AM, Knudsen C, Lai D, Kannangara R, Mikkelsen L, Motawia MS, Olsen CE, Sato S, Tabata S, Jørgensen K, Møller BL, Rook F. Genomic clustering of cyanogenic glucoside biosynthetic genes aids their identification in Lotus japonicus and suggests the repeated evolution of this chemical defence pathway. Plant J 2011; 68:273-86. [PMID: 21707799 DOI: 10.1111/j.1365-313x.2011.04685.x] [Citation(s) in RCA: 114] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Cyanogenic glucosides are amino acid-derived defence compounds found in a large number of vascular plants. Their hydrolysis by specific β-glucosidases following tissue damage results in the release of hydrogen cyanide. The cyanogenesis deficient1 (cyd1) mutant of Lotus japonicus carries a partial deletion of the CYP79D3 gene, which encodes a cytochrome P450 enzyme that is responsible for the first step in cyanogenic glucoside biosynthesis. The genomic region surrounding CYP79D3 contains genes encoding the CYP736A2 protein and the UDP-glycosyltransferase UGT85K3. In combination with CYP79D3, these genes encode the enzymes that constitute the entire pathway for cyanogenic glucoside biosynthesis. The biosynthetic genes for cyanogenic glucoside biosynthesis are also co-localized in cassava (Manihot esculenta) and sorghum (Sorghum bicolor), but the three gene clusters show no other similarities. Although the individual enzymes encoded by the biosynthetic genes in these three plant species are related, they are not necessarily orthologous. The independent evolution of cyanogenic glucoside biosynthesis in several higher plant lineages by the repeated recruitment of members from similar gene families, such as the CYP79s, is a likely scenario.
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Affiliation(s)
- Adam M Takos
- Plant Biochemistry Laboratory, Department of Plant Biology and Biotechnology, University of Copenhagen, 1871 Frederiksberg, Denmark
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12
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Sánchez-Pérez R, Jørgensen K, Motawia MS, Dicenta F, Møller BL. Tissue and cellular localization of individual beta-glycosidases using a substrate-specific sugar reducing assay. Plant J 2009; 60:894-906. [PMID: 19682295 DOI: 10.1111/j.1365-313x.2009.03997.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Traditional methods to localize beta-glycosidase activity in tissue sections have been based on incubation with the general substrate 6-bromo-2-naphthyl-beta-d-glucopyranoside. When hydrolysed in the presence of salt zinc compounds, 6-bromo-2-naphthyl-beta-d-glucopyranoside affords the formation of an insoluble coloured product. This technique does not distinguish between different beta-glycosidases present in the tissue. To be able to monitor the occurrence of individual beta-glycosidases in different tissues and cell types, we have developed a versatile histochemical method that can be used for localization of any beta-glycosidase that upon incubation with its specific substrate releases a reducing sugar. Experimentally, the method is based on hydrolysis of the specific substrate followed by oxidation of the sugar released by a tetrazolium salt (2,3,5-triphenyltetrazolium chloride) that forms a red insoluble product when reduced. The applicability of the method was demonstrated by tissue and cellular localization of two beta-glucosidases, amygdalin hydrolase and prunasin hydrolase, in different tissues and cell types of almond. In those cases where the analysed tissue had a high content of reducing sugars, this resulted in strong staining of the background. This interfering staining of the background was avoided by prior incubation with sodium borohydride. The specificity of the devised method was demonstrated in a parallel localization study using a specific antibody towards prunasin hydrolase.
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Affiliation(s)
- Raquel Sánchez-Pérez
- Plant Biochemistry Laboratory, Department of Plant Biology and Biotechnology, University of Copenhagen, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark.
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13
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Hansen PI, Spraul M, Dvortsak P, Larsen FH, Blennow A, Motawia MS, Engelsen SB. Starch phosphorylation--maltosidic restrains upon 3'- and 6'-phosphorylation investigated by chemical synthesis, molecular dynamics and NMR spectroscopy. Biopolymers 2009; 91:179-93. [PMID: 18985674 DOI: 10.1002/bip.21111] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Phosphorylation is the only known in vivo substitution of starch, yet no structural evidence has been provided to explain its implications of the amylosidic backbone and its stimulating effects on starch degradation in plants. In this study, we provide evidence for a major influence on the glucosidic bond in starch specifically induced by the 3-O-phosphate. Two phosphorylated maltose model compounds were synthesized and subjected to combined molecular dynamics (MD) studies and 950 MHz NMR studies. The two phosphorylated disaccharides represent the two possible phosphorylation sites observed in natural starches, namely maltose phosphorylated at the 3'- and 6'-position (maltose-3'-O-phosphate and maltose-6'-O-phosphate). When compared with maltose, both of the maltose-phosphates exhibit a restricted conformational space of the alpha(1-->4) glycosidic linkage. When maltose is phosphorylated in the 3'-position, MD and NMR show that the glucosidic space is seriously restricted to one narrow potential energy well which is strongly offset from the global potential energy well of maltose and almost 50 degrees degrees from the Phi angle of the alpha-maltose crystal structure. The driving force is primarily steric, but the configuration of the structural waters is also significantly altered. Both the favored conformation of the maltose-3'-phosphate and the maltose-6'-phosphate align well into the 6-fold double helical structure of amylopectin when the effects on the glucosidic bond are not taken into account. However, the restrained geometry of the glucosidic linkage of maltose-3'-phosphate cannot be accommodated in the helical structure, suggesting a major local disturbing effect, if present in the starch granule semi-crystalline lattice.
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Affiliation(s)
- Peter I Hansen
- Department of Food Science, Quality and Technology, University of Copenhagen, Rolighedsvej 30, DK-1958 Frederiksberg C, Denmark
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14
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Damager I, Jensen MT, Olsen CE, Blennow A, Møller BL, Svensson B, Motawia MS. Chemical synthesis of a dual branched malto-decaose: a potential substrate for alpha-amylases. Chembiochem 2005; 6:1224-33. [PMID: 15981193 DOI: 10.1002/cbic.200400449] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [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: 11/10/2022]
Abstract
A convergent block strategy for general use in efficient synthesis of complex alpha-(1-->4)- and alpha-(1-->6)-malto-oligosaccharides is demonstrated with the first chemical synthesis of a malto-oligosaccharide, the decasaccharide 6,6''''-bis(alpha-maltosyl)-maltohexaose, with two branch points. Using this chemically defined branched oligosaccharide as a substrate, the cleavage pattern of seven different alpha-amylases were investigated. Alpha-amylases from human saliva, porcine pancreas, barley alpha-amylase 2 and recombinant barley alpha-amylase 1 all hydrolysed the decasaccharide selectively. This resulted in a branched hexasaccharide and a branched tetrasaccharide. Alpha-amylases from Asperagillus oryzae, Bacillus licheniformis and Bacillus sp. cleaved the decasaccharide at two distinct sites, either producing two branched pentasaccharides, or a branched hexasaccharide and a branched tetrasaccharide. In addition, the enzymes were tested on the single-branched octasaccharide 6-alpha-maltosyl-maltohexaose, which was prepared from 6,6''''-bis(alpha-maltosyl)-maltohexaose by treatment with malt limit dextrinase. A similar cleavage pattern to that found for the corresponding linear malto-oligosaccharide substrate was observed.
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Affiliation(s)
- Iben Damager
- The Carbohydrate Chemistry Group, Plant Biochemistry Laboratory, Department of Plant Biology and Center for Molecular Plant Physiology, The Royal Veterinary and Agricultural University, 1871 Frederiksberg C, Copenhagen, Denmark
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15
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Corzana F, Motawia MS, Hervé du Penhoat C, van den Berg F, Blennow A, Perez S, Engelsen SB. Hydration of the Amylopectin Branch Point. Evidence of Restricted Conformational Diversity of the α-(1→6) Linkage. J Am Chem Soc 2004; 126:13144-55. [PMID: 15469314 DOI: 10.1021/ja048622y] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The hydration behavior of a model compound for the amylopectin branch point, methyl 6'-alpha-maltosyl-alpha-maltotrioside, was investigated by combining molecular dynamics simulations in explicit water, 500 MHz NMR spectroscopy, including pulsed field gradient diffusion measurements, and exploratory multivariate data analysis. In comparison with results on a tetrasaccharide analogue, the study reveals that the conformational diversity of the three-bond alpha-(1-->6) linkage becomes quite limited in aqueous solution upon the addition of a fifth glucose residue that elongates the alpha-(1-->6) branch. This investigation reveals two plausible starch branch point structures, one that permits the formation of double helices and one that is adapted for interconnection of double helices. The apparent rigidity of the former is explained by the presence of water pockets/bridges in the vicinity of the branch point that lock the pentasaccharide structure into one conformational family that is able to accommodate the creation of the double-helical amylopectin structure.
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Affiliation(s)
- Francisco Corzana
- Contribution from the Centre for Advanced Food Studies (LMC), The Royal Veterinary and Agricultural University (KVL), Rolighedsvej 30, DK-1958 Frederiksberg C, Denmark
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16
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Corzana F, Motawia MS, Du Penhoat CH, Perez S, Tschampel SM, Woods RJ, Engelsen SB. A hydration study of (1-->4) and (1-->6) linked alpha-glucans by comparative 10 ns molecular dynamics simulations and 500-MHz NMR. J Comput Chem 2004; 25:573-86. [PMID: 14735575 PMCID: PMC4201036 DOI: 10.1002/jcc.10405] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The hydration behavior of two model disaccharides, methyl-alpha-D-maltoside (1) and methyl-alpha-D-isomaltoside (2), has been investigated by a comparative 10 ns molecular dynamics study. The detailed hydration of the two disaccharides was described using three force fields especially developed for modeling of carbohydrates in explicit solvent. To validate the theoretical results the two compounds were synthesized and subjected to 500 MHz NMR spectroscopy, including pulsed field gradient diffusion measurements (1: 4.0. 10(-6) cm(2). s(-1); 2: 4.2. 10(-6) cm(2). s(-1)). In short, the older CHARMM-based force field exhibited a more structured carbohydrate-water interaction leading to better agreement with the diffusional properties of the two compounds, whereas especially the alpha-(1-->6) linkage and the primary hydroxyl groups were inaccurately modeled. In contrast, the new generation of the CHARMM-based force field (CSFF) and the most recent version of the AMBER-based force field (GLYCAM-2000a) exhibited less structured carbohydrate-water interactions with the result that the diffusional properties of the two disaccharides were underestimated, whereas the simulations of the alpha-(1-->6) linkage and the primary hydroxyl groups were significantly improved and in excellent agreement with homo- and heteronuclear coupling constants. The difference between the two classes of force field (more structured and less structured carbohydrate-water interaction) was underlined by calculation of the isotropic hydration as calculated by radial pair distributions. At one extreme, the radial O em leader O pair distribution function yielded a peak density of 2.3 times the bulk density in the first hydration shell when using the older CHARMM force field, whereas the maximum density observed in the GLYCAM force field was calculated to be 1.0, at the other extreme.
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Affiliation(s)
- Francisco Corzana
- Food Technology, Department of Dairy and Food Science, The Royal Veterinary and Agricultural University, Rolighedsvej 30, DK-1958 Frederiksberg C, Denmark
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17
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Mori H, Bak-Jensen KS, Gottschalk TE, Motawia MS, Damager I, Møller BL, Svensson B. Modulation of activity and substrate binding modes by mutation of single and double subsites +1/+2 and -5/-6 of barley alpha-amylase 1. Eur J Biochem 2001; 268:6545-58. [PMID: 11737209 DOI: 10.1046/j.0014-2956.2001.02609.x] [Citation(s) in RCA: 31] [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] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Enzymatic properties of barley alpha-amylase 1 (AMY1) are altered as a result of amino acid substitutions at subsites -5/-6 (Cys95-->Ala/Thr) and +1/+2 (Met298-->Ala/Asn/Ser) as well as in the double mutants, Cys95-->Ala/Met298-->Ala/Asn/Ser. Cys95-->Ala shows 176% activity towards insoluble Blue Starch compared to wild-type AMY1, kcat of 142 and 211% towards amylose DP17 and 2-chloro-4-nitrophenyl beta-d-maltoheptaoside (Cl-PNPG7), respectively, but fivefold to 20-fold higher Km. The Cys95-->Thr-AMY1 AMY2 isozyme mimic exhibits the intermediary behaviour of Cys95-->Ala and wild-type. Met298-->Ala/Asn/Ser have slightly higher to slightly lower activity for starch and amylose, whereas kcat and kcat/Km for Cl-PNPG7 are < or = 30% and < or = 10% of wild-type, respectively. The activity of Cys95-->Ala/Met298-->Ala/Asn/Ser is 100-180% towards starch, and the kcat/Km is 15-30%, and 0.4-1.1% towards amylose and Cl-PNPG7, respectively, emphasizing the strong impact of the Cys95-->Ala mutation on activity. The mutants therefore prefer the longer substrates and the specificity ratios of starch/Cl-PNPG7 and amylose/Cl-PNPG7 are 2.8- to 270-fold and 1.2- to 60-fold larger, respectively, than of wild-type. Bond cleavage analyses show that Cys95 and Met298 mutations weaken malto-oligosaccharide binding near subsites -5 and +2, respectively. In the crystal structure Met298 CE and SD (i.e., the side chain methyl group and sulfur atom) are near C(6) and O(6) of the rings of the inhibitor acarbose at subsites +1 and +2, respectively, and Met298 mutants prefer amylose for glycogen, which is hydrolysed with a slightly lower activity than by wild-type. Met298 AMY1 mutants and wild-type release glucose from the nonreducing end of the main-chain of 6"'-maltotriosyl-maltohexaose thus covering subsites -1 to +5, while productive binding of unbranched substrate involves subsites -3 to +3.
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Affiliation(s)
- H Mori
- Carlsberg Laboratory, Department of Chemistry, Gamle Carlsberg, Copenhagen Valby, Denmark
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18
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Damager I, Denyer K, Motawia MS, Møller BL, Blennow A. The action of starch synthase II on 6"'-alpha-maltotriosyl-maltohexaose comprising the branch point of amylopectin. Eur J Biochem 2001; 268:4878-84. [PMID: 11559356 DOI: 10.1046/j.1432-1327.2001.02413.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The principle of using a chemically synthesized, well-defined branched oligosaccharide to provide a more detailed knowledge of the substrate specificity of starch synthase II (SSII) is demonstrated. The branched nonasaccharide, 6"'-alpha-maltotriosyl-maltohexaose, was investigated as a primer for particulate SSII using starch granules prepared from the low-amylose pea mutant lam as the enzyme source. The starch granule preparation from the lam pea mutant contains no starch synthases other than SSII and is devoid of alpha-amylase, beta-amylase and phosphorylase activity. SSII was demonstrated to catalyse a specific nonprocessive elongation of the nonreducing end of the shortest unit chain of 6"'-alpha-maltotriosyl-maltohexaose, i.e. the maltotriose chain. Maltotriose and maltohexaose, representing the two linear building units of the branched nonasaccharide, were also tested as primers for SSII. Maltotriose was elongated more efficiently than 6"'-alpha-maltotriosyl-maltohexaose and maltohexaose was used less efficiently. Compared to the surface exposed alpha-glucan chains of the granule bound amylopectin molecules, all three soluble oligosaccharides tested were poor primers for SSII. This indicates that in vivo, the soluble oligosaccharides supposedly released as result of amylopectin trimming reactions are not re-introduced into starch biosynthetic reactions via the action of the granule bound fraction of SSII.
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Affiliation(s)
- I Damager
- Plant Biochemistry Laboratory, Department of Plant Biology, The Royal Veterinary and Agricultural University, Copenhagen, Denmark
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19
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Motawia MS, Olsen CE, Denyer K, Smith AM, Møller BL. Synthesis of 4'-O-acetyl-maltose and alpha-D-galactopyranosyl-(1-->4)-D-glucopyranose for biochemical studies of amylose biosynthesis. Carbohydr Res 2001; 330:309-18. [PMID: 11270809 DOI: 10.1016/s0008-6215(00)00306-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [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: 10/17/2022]
Abstract
The chemical synthesis of the title compounds as maltose analogs, in which the non-reducing end is modified by acetylation of the 4'-OH group or by reversing its configuration, is reported. For synthesis of the 4'-O-acetylated analog, beta-maltose was converted into its per-O-benzylated-4',6'-O-benzylidene derivative followed by removal of the benzylidene acetal function and selective silylation at C-6'. Acetylation at C-4' of the obtained silylated compound followed by removal of the benzyl ether protecting groups and subsequent desilylation afforded the desired analog. The other maltose analog was synthesized via the glycosidation reaction between the glycosyl donor, O-(2,3,4,6-tetra-O-benzyl-alpha/beta-D-galactopyranosyl)trichloroacetimidate and the glycosyl acceptor, phenyl 2,3,6-tri-O-benzyl-1-thio-beta-D-glucopyranoside followed by removal of the phenylthio group and debenzylation to provide the desired analog.
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Affiliation(s)
- M S Motawia
- Department of Plant Biology, The Royal Veterinary and Agricultural University, Copenhagen, Denmark.
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20
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Damager I, Olsen CE, Møller BL, Motawia MS. Chemical synthesis of 6"'-alpha-maltotriosyl-maltohexaose as substrate for enzymes in starch biosynthesis and degradation. Carbohydr Res 1999; 320:19-30. [PMID: 10515061 DOI: 10.1016/s0008-6215(99)00131-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [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
A branched nonasaccharide 6"'-alpha-maltotriosyl-maltohexaose was synthesised in 40 steps from D-glucose and maltose. Phenyl O-(2,3,4,6-tetra-O-benzyl-alpha-D-glucopyranosyl)-(1-->4)-O- (2,3,6-tri-O-benzyl-alpha-D-glucopyranosyl)-(1-->4)-2,3-di-O-benzyl-1-th io- beta-D-glucopyranoside and O-(2,3,4,6-tetra-O-benzyl-alpha-D-glucopyranosyl)-(1-->4)-O-(2,3,6-tri- O-benzyl-alpha-D-glucopyranosyl)-(1-->4)-2,3,6-tri-O-benzyl-alpha, beta-D-glucopyranosyl trichloroacetimidate were coupled by a general condensation reaction to form the per-O-benzylated branched hexasaccharide phenyl thioglycoside. The phenylthio group of this compound was converted into a trichloroacetimidate, which was coupled with phenyl O-(2,3,6-tri-O-benzyl-alpha-D-glucopyranosyl)-(1-->4)-O-(2,3,6-tri-O- benzyl-alpha-D-glucopyranosyl)-(1-->4)-2,3,6-tri-O-benzyl-1-thio-beta-D- glucopyranoside to afford the per-O-benzylated branched nonasaccharide phenyl thioglycoside. Replacement of the phenylthio group with a free OH-group followed by hydrogenolysis gave the desired product. The synthons reported for this synthesis constitute a versatile tool for the chemical synthesis of other complex carbohydrates.
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Affiliation(s)
- I Damager
- Department of Plant Biology, Royal Veterinary and Agricultural University, Copenhagen, Denmark
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21
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Motawia MS, Olsen CE, Enevoldsen K, Marcussen J, Møller BL. Chemical synthesis of 6'-alpha-maltosyl-maltotriose, a branched oligosaccharide representing the branch point of starch. Carbohydr Res 1995; 277:109-23. [PMID: 8548783 DOI: 10.1016/0008-6215(95)00203-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.5] [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: 01/31/2023]
Abstract
Chemical synthesis of the branched pentasaccharide 6'-alpha-maltosyl-maltotriose (15) is reported, based on the use of one synthon as a glycosyl acceptor and another synthon as a glycosyl donor. The synthon used as glycosyl acceptor was phenyl 2,3,6-tri-O-benzyl-1-thio-beta-D-glucopyranoside (7) and was synthesized from D-glucose with phenyl 2,3-di-O-acetyl-4,6-O-benzylidene-1-thio-beta-D-glucopyranoside and phenyl 2,3-di-O-benzyl-4,6-O-benzylidene-1-thio-beta-D-glucopyranoside as key intermediates. The synthon used as glycosyl donor was O-(2,3,4,6-tetra-O-benzyl-alpha-D-glucopyranosyl)-(1-->4)-O-(2,3,6-tri-O -benzyl - alpha-D-glucopyranosyl)-(1-->6)-O-[(2,3,4,6-tetra-O-benzyl-alpha-D- glucopyranosyl)-(1-->4)]-2,3-di-O-benzyl-alpha,beta-D-glucopyranosyl trichloroacetimidate (12) and was synthesized from phenyl O-2,3,4,6-tetra-O-benzyl-alpha-D-glucopyranosyl)-(1-->4)-O-(2,3,6-tri-O- benzyl- alpha-D-glucopyranosyl)-(1-->6)-O-[(2,3,4,6-tetra-O-acetyl-alpha-D- glucopyranosyl)-(1-->4)]-2,3-di-O-acetyl-1-thio-beta-D-glucopyranoside with O-(2,3,4,6-tetra-O-benzyl-alpha-D-glucopyranosyl)-(1-->4)-O-(2,3,6-tri-O - benzyl-alpha-D-glucopyranosyl)-(1-->4)]-2,3-di-O-benzyl-D-glucopyranose as an intermediate. Condensation of compounds 7 and 12 followed by removal of the phenylthio group and debenzylation provided the branched pentasaccharide 15. Alternatively, the branched pentasaccharide was produced from amylopectin by consecutive alpha- and beta-amylase treatments and purified by chromatography. The identity of the products obtained by chemical synthesis and enzymatic hydrolysis is documented by 1H and 13C NMR spectra.
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Affiliation(s)
- M S Motawia
- Department of Plant Biology, Royal Veterinary and Agricultural University, Copenhagen, Denmark
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22
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Motawia MS, Meldal M, Sofan M, Stein P, Pedersen EB, Nielsen C. 2’-Deoxypuromycin: Synthesis and Antiviral Evaluation. SYNTHESIS-STUTTGART 1995. [DOI: 10.1055/s-1995-3892] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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23
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Motawia MS, Olsen CE, Møller BL, Marcussen J. Chemical synthesis and NMR spectra of a protected branched-tetrasaccharide thioglycoside, a useful intermediate for the synthesis of branched oligosaccharides. Carbohydr Res 1994; 252:69-84. [PMID: 8137372 DOI: 10.1016/0008-6215(94)90006-x] [Citation(s) in RCA: 26] [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] [Indexed: 01/29/2023]
Abstract
Acid-catalyzed thiophenolysis of per-O-acetylated 1,6-anhydromaltose (3) gave phenyl 2,3-di-O-acetyl-4-O-(2,3,4,6-tetra-O-acetyl-alpha-D- glucopyranosyl)-1-thio-beta-D-glucopyranoside (4) in quantitative yield. Phenyl 4-O-alpha-D-glucopyranosyl-1-thio-beta-D-glucopyranoside (5) was obtained by acid-catalyzed thiophenolysis of maltose octaacetate (2), using trimethylsilyl triflate as catalyst, and subsequent deacetylation. Standard benzylation of 5 gave phenyl 2,3-di-O-benzyl-4-O- (2,3,4,6-tetra-O-benzyl-alpha-D-glucopyranosyl)-1-thio-beta-D-glucopy ran oside (6) which upon treatment with N-bromosuccinimide in aqueous acetone gave 2,3,6-tri-O-benzyl-4-O-(2,3,4,6-tetra-O-benzyl-alpha-D- glucopyranosyl)-D-glucopyranose (8). Compound 8 was treated with trichloroacetonitrile in the presence of anhydrous potassium carbonate to give 2,3,6-tri-O-benzyl-4-O-(2,3,4,6-tetra-O-benzyl- alpha-D-glucopyranosyl) -alpha,beta-D-glucopyranosyl trichloroacetimidate (9), which was effectively used as the glycosyl donor in the condensation reaction with compound 4, using trimethylsilyl triflate as catalyst, to obtain the branched tetrasaccharides phenyl O-[2,3,4,6-tetra-O-benzyl-alpha-D-glucopyranosyl)- (1-->4)]-O-(2,3,6-tri-O-benzyl-alpha-D-glucopyranosyl)-(1-->6)-O-(2,3,4, 6- tetra-O-acetyl-alpha-D-glucopyranosyl)-(1-->4)-2,3-di-O-acetyl-1-thio-be ta-D- glucopyranoside (10) and phenyl O-[(2,3,4,6-tetra-O-benzyl-alpha-D-glucopyranosyl)-(1-->4)]- O-(2,3,4-tri-O-benzyl-beta-D-glucopyranosyl)-(1-->6)-O-(2,3,4,6-tetra-O- acetyl- alpha-D-glucopyranosyl)-(1-->4)-2,3-di-O-acetyl-1-thio-beta-D-glucopy ran oside (11) in 67 and 21% yield, respectively. A complete NMR interpretation of 10 is presented. Alternative methodologies for the synthesis of the branched tetrasaccharides were investigated. Chemical synthesis of the phenyl thioglycoside 5 was achieved by deacetylation of 4. Reaction of 6 with diethylaminosulfur trifluoride in the presence of N-bromosuccinimide gave 2,3,6-tri-O-benzyl-4-O-(2,3,4,6-tetra-O-benzyl-alpha-D- glucopyranosyl)-alpha,beta-D-glucopyranosyl fluoride (7) in 78% yield. Subsequent condensation of 7 and 4, using the combination silver perchlorate-stannous chloride as catalyst, gave the corresponding branched tetrasaccharides 10 and 11 in 55 and 10% yield, respectively.
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Affiliation(s)
- M S Motawia
- Department of Plant Biology, Royal Veterinary & Agricultural University, Frederiksberg C, Copenhagen, Denmark
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Motawia MS, Jørgensen PT, Larnkjær A, Pedersen EB, Nielsen C. Synthesis of 5-dialkylaminomethyl-3′-azido and 3′-fluoro-2′,3′-dideoxyuridines for evaluation as anti-HIV agents. Monatsh Chem 1993. [DOI: 10.1007/bf00808509] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Pedersen EB, Dueholm KL, El-emam A, Kofoed T, El-Torgoman AAM, Motawia MS, Aly YL, J⊘rgensen PT, El-barbary AAK, Khodair A, Larsen E. Thio Nucleoside Derivatives as Intermediates or Target Compounds in the Attempt of Finding New Agents Against HIV. PHOSPHORUS SULFUR 1993. [DOI: 10.1080/10426509308038166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Dueholm KL, Motawia MS, Pedersen EB, Nielsen C, Lundt I. Synthesis of 3'-alkylthio-2',3'-dideoxy nucleosides with potential anti-HIV activity from 2-deoxy-D-ribose, using a phosphorus pentoxide reagent. Arch Pharm (Weinheim) 1992; 325:597-601. [PMID: 1332647 DOI: 10.1002/ardp.19923250914] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [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: 12/26/2022]
Abstract
Direct condensation of 2-deoxy-D-ribose (1) with mercaptans using the P4O10/H2O/Bu3N reagent in chloroform resulted in coupling at C-3 to give the anomeric mixtures of the corresponding pentopyranoses 2 and pentofuranoses 3. After acetylation with acetic anhydride in dry pyridine of these 3-alkylthio pentofuranoses, coupling with the nucleobases uracil, thymine, and cytosine in accordance with the Friedel-Crafts catalyzed silyl Hilbert-Johnson method yielded the acetylated D-erythro nucleosides 7 as anomeric mixtures, separable only by means of chromatography either before or after deprotection with ammonia. The nucleosides 8a-e were devoid of any activity against HSV-1 and HIV-1.
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Affiliation(s)
- K L Dueholm
- Department of Chemistry, Odense University, Denmark
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El-Torgoman AM, Motawia MS, Kj�rsgaard U, Pedersen EB. New route for the synthesis of 2-thiouracil analogues of 3?-azido-2?,3?-dideoxy nucleosides. Monatsh Chem 1992. [DOI: 10.1007/bf00810948] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Wengel J, Motawia MS, Pedersen EB, Nielsen CM. Analogues of the antibiotic puromycin as potential prodrugs of 3′-amino-3′-deoxythymidine. J Heterocycl Chem 1992. [DOI: 10.1002/jhet.5570290102] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Motawia MS, Abdel-Megied AE, Pedersen EB, Nielsen CM, Ebbesen P. Synthesis of 5-alkoxymethyl derivatives of 3'-amino-2',3'-dideoxyuridine and evaluation of their activity against HIV and cancer. Acta Chem Scand (Cph) 1992; 46:77-81. [PMID: 1599798 DOI: 10.3891/acta.chem.scand.46-0077] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
5-Alkoxymethyluracils 2a-c have been prepared by acid-catalyzed etherification of 5-hydroxymethyluracil (1). Compounds 1, 2a-c, 5-methoxymethyl- and 5-benzyloxymethyl-uracil were silylated and coupled with 1,5-di-O-acetyl-3-phthalimido-2,3-dideoxy-beta- D-erythro-pentofuranose (3), in the presence of trimethylsilyl triflate as a catalyst, to give the corresponding 3'-phthalimido-2',3'-dideoxynucleosides 5a-f and 6 which on treatment with 33% methylamine-ethanol afforded the corresponding 3'-amino-2',3'-dideoxynucleosides 7a-f and 8 in high yields. Compound 7d showed colony inhibition when tested against human epidermoid cervical cancer cells. Nucleosides 5a-e, 7a-f and 8 did not show any significant activity against HIV-1.
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Affiliation(s)
- M S Motawia
- Department of Chemistry, Odense University, Denmark
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Abstract
Treatment of 3'-amino-3'-deoxythymidine (1) with carboxylic acid anhydrides afforded the corresponding acylamino derivatives 2a-f. Reaction of 1 with a variety of isothiocyanates led to the corresponding thioureido derivatives 3a-i. Also, conversion of 1 into 3'-carbylamino-3'-deoxythymidine (7) is reported. The compounds 2, 3, and 8 were evaluated for their anti-HIV activity in MT-4 cells, but did not show sufficient efficacy.
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Affiliation(s)
- M S Motawia
- Department of Chemistry, Odense University, Denmark
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Motawia MS, Pedersen EB, Suwinski J, Nielsen CM. Synthesis of 3'-(4-nitroimidazol-1-yl)-2',3'-dideoxynucleosides of pyrimidine analogues and their biological evaluation against HIV. Arch Pharm (Weinheim) 1990; 323:949-53. [PMID: 2096797 DOI: 10.1002/ardp.19903231203] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [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: 12/30/2022]
Abstract
Reaction of 1,5-di-O-acetyl-2,3-dideoxy-3-phthalimido-beta-D-erythro-pento-fur anose (1) with silylated pyrimidinediones 2a-c using the Lewis acid trimethylsilyl triflate as catalyst afforded nucleosides 3a-c and 4a,c which were deprotected with 33% methylamine/ethanol to give the corresponding 3-aminonucleosides 5a-c and 6. These were reacted with 1,4-dinitroimidazoles 7a,b to give the 3-imidazolyldideoxynucleosides 8a,b and 9a-f. At sub-toxic concentrations these compounds were ineffective against HIV-1.
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Affiliation(s)
- M S Motawia
- Department of Chemistry, Odense University, Denmark
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Motawia MS, Pedersen EB. Synthesis of 4- O-Acetyl-2,3-dideoxy-3-(tetrabromophthalimido)-D- threo-pentopyranosyl Chloride. SYNTHESIS-STUTTGART 1988. [DOI: 10.1055/s-1988-27711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Motawia MS, Nawwar GAM, Andreassen ES, Jacobsen JP, Pedersen EB. Coupling of Unprotected 2-Deoxy-D-ribose at C-3 as a New Route to 2,3-Dideoxy-3-phthalimido-D-pentoses. European J Org Chem 1987. [DOI: 10.1002/jlac.198719870881] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Motawia MS, Andreassen ES, Pedersen EB, Jacobsen JP. Anomalously Coupled Nucleosides, III. Coupling of Unprotected 2-Deoxy-D-ribose at C-3 withN6-Acyladenines as a New Route to Isomers of Adenosine. European J Org Chem 1987. [DOI: 10.1002/jlac.198719870829] [Citation(s) in RCA: 6] [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: 11/09/2022]
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Nabih I, Zayed AA, Metri J, Kamel M, Motawia MS. Synthesis of some tetrahydronaphthyl-1,2,4-triazines of possible schistosomicidal activity. Pharmazie 1984; 39:862-3. [PMID: 6531399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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