101
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Kakwere H, Chun CKY, Jolliffe KA, Payne RJ, Perrier S. Polymer–peptide chimeras for the multivalent display of immunogenic peptides. Chem Commun (Camb) 2010; 46:2188-90. [DOI: 10.1039/b924112d] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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102
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Hojo H, Katayama H, Nakahara Y. Progress in the Ligation Chemistry for Glycoprotein Synthesis. TRENDS GLYCOSCI GLYC 2010. [DOI: 10.4052/tigg.22.269] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Hironobu Hojo
- Department of Applied Biochemistry, Institute of Glycoscience, Tokai University, 4-1-1 Kitakaname, Hiratsuka, Kanagawa 259-1292, Japan
| | - Hidekazu Katayama
- Department of Applied Biochemistry, Institute of Glycoscience, Tokai University, 4-1-1 Kitakaname, Hiratsuka, Kanagawa 259-1292, Japan
| | - Yoshiaki Nakahara
- Department of Applied Biochemistry, Institute of Glycoscience, Tokai University, 4-1-1 Kitakaname, Hiratsuka, Kanagawa 259-1292, Japan
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103
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Boons GJ. Bioorthogonal chemical reporter methodology for visualization, isolation and analysis of glycoconjugates. CARBOHYDRATE CHEMISTRY 2010; 36:152-167. [PMID: 21785678 PMCID: PMC3142093 DOI: 10.1039/9781849730891-00152] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The recent development of metabolic oligosaccharide engineering combined with bioorthogonal reactions is providing unique opportunities to detect, image, and isolate glycoconjugates of living cells, tissues, and model organisms. In this methodology, exogenously-supplied non-natural sugars are fed to cells and employed by the biosynthetic machinery for the biosynthesis of neoglycoconjugates. In this way, reactive functional groups such as ketones, azides, and thiols have been incorporated into sialic acid, galactosamine, glucosamine, and fucose moieties of glycoconjugates. A range of bioorthogonal reactions have been described that functionalize the chemical 'tags' for imaging, isolation, and drug delivery.
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Affiliation(s)
- Geert-Jan Boons
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens Georgia 30606, USA
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104
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Jiménez-Barbero J, Dragoni E, Venturi C, Nannucci F, Ardá A, Fontanella M, André S, Cañada FJ, Gabius HJ, Nativi C. Alpha-O-linked glycopeptide mimetics: synthesis, conformation analysis, and interactions with viscumin, a galactoside-binding model lectin. Chemistry 2009; 15:10423-31. [PMID: 19746469 DOI: 10.1002/chem.200901077] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Efficient cycloaddition of a silylidene-protected galactal with a suitable heterodiene yielded the basis for a facile diastereoselective route to a glycopeptide-mimetic scaffold. Its carbohydrate part was further extended by beta1-3-linked galactosylation. The pyranose rings retain their (4)C(1) chair conformation, as shown by molecular modeling and NMR spectroscopy, and the typical exo-anomeric geometry was observed for the disaccharide. The expected bioactivity was ascertained by saturation-transfer-difference NMR spectroscopy by using the galactoside-specific plant toxin viscumin as a model lectin. The experimental part was complemented by molecular docking. The described synthetic route and the strategic combination of computational and experimental techniques to reveal conformational properties and bioactivity establish the prepared alpha-O-linked glycopeptide mimetics as promising candidates for further exploitation of this scaffold to give O-glycans for lectin blocking and vaccination.
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Affiliation(s)
- Jesús Jiménez-Barbero
- Chemical and Physical Biology, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain.
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105
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Dutot L, Lécorché P, Burlina F, Marquant R, Point V, Sagan S, Chassaing G, Mallet JM, Lavielle S. Glycosylated cell-penetrating peptides and their conjugates to a proapoptotic peptide: preparation by click chemistry and cell viability studies. J Chem Biol 2009; 3:51-65. [PMID: 19899012 DOI: 10.1007/s12154-009-0031-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2009] [Accepted: 10/01/2009] [Indexed: 11/25/2022] Open
Abstract
UNLABELLED Cell-penetrating peptides (CPPs), which are usually short basic peptides, are able to cross cell membranes and convey bioactive cargoes inside cells. CPPs have been widely used to deliver inside cells peptides, proteins, and oligonucleotides; however, their entry mechanisms still remain controversial. A major problem concerning CPPs remains their lack of selectivity to target a specific type of cell and/or an intracellular component. We have previously shown that myristoylation of one of these CPPs affected the intracellular distribution of the cargo. We report here on the synthesis of glycosylated analogs of the cell-penetrating peptide (R6/W3): Ac-RRWWRRWRR-NH(2). One, two, or three galactose(s), with or without a spacer, were introduced into the sequence of this nonapeptide via a triazole link, the Huisgen reaction being achieved on a solid support. Four of these glycosylated CPPs were coupled via a disulfide bridge to the proapoptotic KLAK peptide, (KLAKLAKKLAKLAK), which alone does not enter into cells. The effect on cell viability and the uptake efficiency of different glycosylated conjugates were studied on CHO cells and were compared to those of the nonglycosylated conjugates: (R6/W3)S-S-KLAK and penetratinS-S-KLAK. We show that glycosylation significantly increases the cell viability of CHO cells compared to the nonglycosylated conjugates and concomitantly decreases the internalization of the KLAK cargo. These results suggest that glycosylation of CPP may be a key point in targeting specific cells. ELECTRONIC SUPPLEMENTARY MATERIAL The online version of this article (doi:10.1007/s12154-009-0031-9) contains supplementary material, which is available to authorized users.
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106
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Reaction of N-Fmoc aspartic anhydride with glycosylamines: a simple entry to N-glycosyl asparagines. Tetrahedron Lett 2009. [DOI: 10.1016/j.tetlet.2009.08.106] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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107
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Boltje TJ, Buskas T, Boons GJ. Opportunities and challenges in synthetic oligosaccharide and glycoconjugate research. Nat Chem 2009; 1:611-22. [PMID: 20161474 PMCID: PMC2794050 DOI: 10.1038/nchem.399] [Citation(s) in RCA: 536] [Impact Index Per Article: 35.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Synthetic oligosaccharides and glycoconjugates are increasingly used as probes for biological research and as lead compounds for drug and vaccine discovery. These endeavors are, however, complicated by a lack of general methods for the routine preparation of this important class of compounds. Recent development such as one-pot multi-step protecting group manipulations, the use of unified monosaccharide building blocks, the introduction of stereoselective glycosylation protocols, and convergent strategies for oligosaccharide assembly, are beginning to address these problems. Furthermore, oligosaccharide synthesis can be facilitated by chemo-enzymatic methods, which employ a range of glycosyl transferases to modify a synthetic oligosaccharide precursor. Glycosynthases, which are mutant glycosidases, that can readily form glycosidic linkages are addressing a lack of a wide range glycosyltransferases. The power of carbohydrate chemistry is highlighted by an ability to synthesize glycoproteins.
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Affiliation(s)
- Thomas J Boltje
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA, USA
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108
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Buskas T, Thompson P, Boons GJ. Immunotherapy for cancer: synthetic carbohydrate-based vaccines. Chem Commun (Camb) 2009:5335-49. [PMID: 19724783 PMCID: PMC2787243 DOI: 10.1039/b908664c] [Citation(s) in RCA: 158] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Aberrant glycosylation of glycoproteins and glycolipids of cancer cells, which correlates with poor survival rates, is being exploited for the development of immunotherapies for cancer. In particular, advances in the knowledge of cooperation between the innate and adaptive system combined with the implementation of efficient synthetic methods for assembly of oligosaccharides and glycopeptides is providing avenues for the rationale design of vaccine candidates. In this respect, fully synthetic vaccine candidates show great promise because they incorporate only those elements requires for relevant immune responses, and hence do not suffer from immune suppression observed with classical carbohydrate-protein conjugate vaccines. Such vaccines are chemically well-defined and it is to be expected that they can be produced in a reproducible fashion. In this feature article, recent advances in the development of fully synthetic sub-unit carbohydrate-based cancer vaccines will be discussed.
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Affiliation(s)
- Therese Buskas
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602, USA
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109
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Buchan ZA, Bader SJ, Montgomery J. Ketone hydrosilylation with sugar silanes followed by intramolecular aglycone delivery: an orthogonal glycosylation strategy. Angew Chem Int Ed Engl 2009; 48:4840-4. [PMID: 19492383 DOI: 10.1002/anie.200901666] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Gettin' a little sugar-no alcohol required: A procedure for the direct glycosylation of ketones without a hydroxy intermediate enables the site-selective glycosylation of hydroxyketones at the ketone or the alcohol functionality without the use of protecting groups on the aglycone (see scheme). Site selectivity is controlled by the catalyst structure in hydrosilylation and dehydrogenative silylation reactions with sugar silanes. Bn=benzyl.
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Affiliation(s)
- Zachary A Buchan
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA
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110
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Bonache MA, Nuti F, Le Chevalier Isaad A, Real-Fernández F, Chelli M, Rovero P, Papini AM. Synthesis of new ribosylated Asn building blocks as useful tools for glycopeptide and glycoprotein synthesis. Tetrahedron Lett 2009. [DOI: 10.1016/j.tetlet.2009.04.124] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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111
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Buchan Z, Bader S, Montgomery J. Ketone Hydrosilylation with Sugar Silanes Followed by Intramolecular Aglycone Delivery: An Orthogonal Glycosylation Strategy. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200901666] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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112
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113
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114
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Seppälä U, Selby D, Monsalve R, King TP, Ebner C, Roepstorff P, Bohle B. Structural and immunological characterization of the N-glycans from the major yellow jacket allergen Ves v 2: The N-glycan structures are needed for the human antibody recognition. Mol Immunol 2009; 46:2014-21. [DOI: 10.1016/j.molimm.2009.03.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2009] [Accepted: 03/09/2009] [Indexed: 11/26/2022]
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115
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Okamoto R, Souma S, Kajihara Y. Efficient substitution reaction from cysteine to the serine residue of glycosylated polypeptide: repetitive peptide segment ligation strategy and the synthesis of glycosylated tetracontapeptide having acid labile sialyl-T(N) antigens. J Org Chem 2009; 74:2494-501. [PMID: 19236026 DOI: 10.1021/jo8026164] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This paper reports the synthesis of a 40-residue glycopeptide having two antigenic sialyl-T(N) (NeuAc-alpha-(2,6)-GalNAc-Thr) residues in the MUC1 sequence. This target glycopeptide is a tandem repeat form of 20-residue glycopeptides. For the synthesis of this large molecule, native chemical ligation (NCL) at the serine site was used ((Cys)NCL(Ser)). The concept of (Cys)NCL(Ser) relies on the following: (1) conventional NCL between peptide-alpha-thioester and the cysteine residue of another peptide segment; (2) methylation of the thiol that was used for NCL; (3) acidic CNBr conversion of the cysteine residue to the serine residue forming an O-ester linkage; and (4) an O- to N-acyl shift to couple the two glycopeptides through a native amide bond. To synthesize glycopeptide having an acid-labile sugar moiety, a 20-residue glycopeptide-alpha-thioester and 20-residue glycopeptide having a cysteine residue at the N-terminal were synthesized by solid phase glycopeptide synthesis, and then coupled by (Cys)NCL(Ser). As the result of extensive investigation, CNBr activation with an additional acid (trifluoroacetic acid) was found to be essential to obtain good reactivity and yield, and this condition afforded a tandem repeat form of 40-residue sialylglycopeptide having two sialyl-T(N) residues. In addition to this, it was demonstrated that the cysteine thiol protected by the acetoamidomethyl (Acm) group did not react with the CNBr reagent, and therefore (Cys)NCL(Ser) can be used for repetitive native chemical ligation in the presence of a protecting N-terminal cysteine residue with an Acm group.
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Affiliation(s)
- Ryo Okamoto
- International Graduate School of Arts and Sciences, Yokohama City University, 22-2, Seto, Kanazawa-ku, Yokohama, 236-0027, Japan
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116
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Huang W, Li C, Li B, Umekawa M, Yamamoto K, Zhang X, Wang LX. Glycosynthases enable a highly efficient chemoenzymatic synthesis of N-glycoproteins carrying intact natural N-glycans. J Am Chem Soc 2009; 131:2214-23. [PMID: 19199609 DOI: 10.1021/ja8074677] [Citation(s) in RCA: 152] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Homogeneous N-glycoproteins carrying defined natural N-glycans are essential for detailed structural and functional studies. The transglycosylation activity of the endo-beta-N-acetylglucosaminidases from Arthrobacter protophormiae (Endo-A) and Mucor hiemalis (Endo-M) holds great potential for glycoprotein synthesis, but the wild-type enzymes are not practical for making glycoproteins carrying native N-glycans because of their predominant activity for product hydrolysis. In this article, we report studies of two endoglycosidase-based glycosynthases, EndoM-N175A and EndoA-N171A, and their usefulness in constructing homogeneous N-glycoproteins carrying natural N-glycans. The oligosaccharide oxazoline corresponding to the biantennary complex-type N-glycan was synthesized and tested with the two glycosynthases. The EndoM-N175A mutant was able to efficiently transfer the complex-type glycan oxazoline to a GlcNAc peptide and GlcNAc-containing ribonuclease to form the corresponding homogeneous glycopeptide/glycoprotein. The EndoA-N171A mutant did not recognize the complex-type N-glycan oxazoline but could efficiently use the high-mannose-type glycan oxazoline for transglycosylation. These mutants possess the transglycosylation activity but lack the hydrolytic activity toward the product. Kinetic studies revealed that the dramatically enhanced synthetic efficiency of the EndoA-N171A mutant was due to the significantly reduced hydrolytic activity toward both the Man(9)GlcNAc oxazoline and the product as well as to its enhanced activity for transglycosylation. Thus, the two mutants described here represent the first endoglycosidase-based glycosynthases enabling a highly efficient synthesis of homogeneous natural N-glycoproteins.
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Affiliation(s)
- Wei Huang
- Institute of Human Virology and Department of Biochemistry & Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA
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117
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Rich JR, Withers SG. Emerging methods for the production of homogeneous human glycoproteins. Nat Chem Biol 2009; 5:206-15. [PMID: 19295526 DOI: 10.1038/nchembio.148] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Most circulating human proteins exist as heterogeneously glycosylated variants (glycoforms) of an otherwise homogeneous polypeptide. Though glycan heterogeneity is most likely important to glycoprotein function, the preparation of homogeneous glycoforms is important both for the study of the consequences of glycosylation and for therapeutic purposes. This review details selected approaches to the production of homogeneous human N- and O-linked glycoproteins with human-type glycans. Particular emphasis is placed on recent developments in the engineering of glycosylation pathways within yeast and bacteria for in vivo production, and on the in vitro remodeling of glycoproteins by enzymatic means. The future of this field is very exciting.
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Affiliation(s)
- Jamie R Rich
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada
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118
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Piontek C, Varón Silva D, Heinlein C, Pöhner C, Mezzato S, Ring P, Martin A, Schmid F, Unverzagt C. Semisynthesis of a Homogeneous Glycoprotein Enzyme: Ribonuclease C: Part 2. Angew Chem Int Ed Engl 2009; 48:1941-5. [DOI: 10.1002/anie.200804735] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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119
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Piontek C, Varón Silva D, Heinlein C, Pöhner C, Mezzato S, Ring P, Martin A, Schmid F, Unverzagt C. Semisynthese eines homogenen Glycoprotein-Enzyms: Ribonuclease C (Teil 2). Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200804735] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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120
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Corzana F, Busto J, García de Luis M, Jiménez-Barbero J, Avenoza A, Peregrina J. The Nature and Sequence of the Amino Acid Aglycone Strongly Modulates the Conformation and Dynamics Effects of Tn Antigen's Clusters. Chemistry 2009; 15:3863-74. [DOI: 10.1002/chem.200801777] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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121
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Affiliation(s)
- David P Gamblin
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford OX1 3TA, United Kingdom
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122
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de Graaf AJ, Kooijman M, Hennink WE, Mastrobattista E. Nonnatural Amino Acids for Site-Specific Protein Conjugation. Bioconjug Chem 2009; 20:1281-95. [DOI: 10.1021/bc800294a] [Citation(s) in RCA: 161] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Albert J. de Graaf
- Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences (UIPS), Faculty of Science, Utrecht University, P.O. Box 80.082, 3508 TB Utrecht, The Netherlands
| | - Marlous Kooijman
- Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences (UIPS), Faculty of Science, Utrecht University, P.O. Box 80.082, 3508 TB Utrecht, The Netherlands
| | - Wim E. Hennink
- Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences (UIPS), Faculty of Science, Utrecht University, P.O. Box 80.082, 3508 TB Utrecht, The Netherlands
| | - Enrico Mastrobattista
- Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences (UIPS), Faculty of Science, Utrecht University, P.O. Box 80.082, 3508 TB Utrecht, The Netherlands
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123
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Filice M, Bavaro T, Fernandez-Lafuente R, Pregnolato M, Guisan JM, Palomo JM, Terreni M. Chemo-biocatalytic regioselective one-pot synthesis of different deprotected monosaccharides. Catal Today 2009. [DOI: 10.1016/j.cattod.2008.07.016] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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124
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Li X, Huang L, Hu X, Huang X. Thio-arylglycosides with various aglycon para-substituents: a probe for studying chemical glycosylation reactions. Org Biomol Chem 2009; 7:117-27. [PMID: 19081954 PMCID: PMC2677192 DOI: 10.1039/b813048e] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Three series of thioglycosyl donors differing only in their respective aglycon substituents within each series have been prepared as representatives of typical glycosyl donors. The relative anomeric reactivities of these donors were quantified under competitive glycosylation conditions with various reaction time, promoters, solvents and acceptors. Over three orders of magnitude reactivity difference were generated by simple transformation of the para-substituent on the aglycon with methanol as the acceptor, while chemoselectivities became lower with carbohydrate acceptors. Excellent linear correlations were attained between relative reactivity values of donors and sigma(p) values of the substituents in the Hammett plots. This indicates that the glycosylation mechanism remains the same over a wide range of reactivities and glycosylation conditions. The negative slopes of the Hammett plots suggested that electron donating substituents expedite the reactions and the magnitudes of slopes can be rationalized by neighboring group participation as well as electronic properties of the glycon protective groups. Within the same series of donors, less nucleophilic acceptors gave smaller slopes in their Hammett plots. This is consistent with the notion that acceptor nucleophilic attack onto the reactive intermediate is part of the rate limiting step of the glycosylation reaction.
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Affiliation(s)
- Xiaoning Li
- Department of Chemistry, The University of Toledo, 2801 W. Bancroft Street, MS 602, Toledo, OH 43606
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125
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Abstract
Several dendrimers possessing multiple copies of peptides and glycopeptides belonging to the MUC1 eicosapeptide tandem repeat sequence have been prepared. Fmoc-strategy solid-phase peptide synthesis was used to construct the peptides and glycopeptides, which were conjugated to suitably functionalized dendrimer cores using the copper-catalyzed azide-alkyne cycloaddition reaction to produce multivalent peptide and glycopeptide dendrimers.
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126
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Swarts BM, Chang YC, Hu H, Guo Z. Synthesis and CD structural studies of CD52 peptides and glycopeptides. Carbohydr Res 2008; 343:2894-902. [DOI: 10.1016/j.carres.2008.08.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2008] [Revised: 08/21/2008] [Accepted: 08/25/2008] [Indexed: 10/21/2022]
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127
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Fernández-Tejada A, Corzana F, Busto JH, Jiménez-Osés G, Peregrina JM, Avenoza A. Non-natural amino acids as modulating agents of the conformational space of model glycopeptides. Chemistry 2008; 14:7042-58. [PMID: 18604849 DOI: 10.1002/chem.200800460] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The synthesis and conformational analysis in aqueous solution of different alpha-methyl-alpha-amino acid diamides, derived from serine, threonine, beta-hydroxycyclobutane-alpha-amino acids, and their corresponding model beta-O-glucopeptides, are reported. The study reveals that the presence of an alpha-methyl group forces the model peptides to adopt helix-like conformations. These folded conformations are especially significant for cyclobutane derivatives. Interestingly, this feature was also observed in the corresponding model glucopeptides, thus indicating that the alpha-methyl group and not the beta-O-glucosylation process largely determines the conformational preference of the backbone in these structures. On the other hand, atypical conformations of the glycosidic linkage were experimentally determined. Therefore, when a methyl group was located at the Cbeta atom with an R configuration, the glycosidic linkage was rather rigid. Nevertheless, when the S configuration was displayed, a significant degree of flexibility was observed for the glycosidic linkage, thus showing both alternate and eclipsed conformations of the psi(s) dihedral angle. In addition, some derivatives exhibited an unusual value for the phi(s) angle, which was far from a value of -60 degrees expected for a conventional beta-O-glycosidic linkage. In this sense, the different conformations exhibited by these molecules could be a useful tool in obtaining systems with conformational preferences "à la carte".
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128
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McGarvey GJ, LeClair CA, Schmidtmann BA. Studies on the stereoselective synthesis of C-allyl glycosides. Org Lett 2008; 10:4727-30. [PMID: 18826234 DOI: 10.1021/ol801710s] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An investigation was carried out to explore the use of sulfoxide donors as common precursors to stereoisomeric C-glycoconjugates of glycoprotein and glycolipid tumor antigens. A study focusing on the effects of reaction conditions and substrate structure on the stereoselectivity of allylation was carried out. Although conditions were realized to selectively afford alpha-allylation products in good to excellent yields, the search for conditions favoring beta-selectivity proved less successful.
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Affiliation(s)
- Glenn J McGarvey
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22901, USA.
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129
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Ochiai H, Huang W, Wang LX. Expeditious chemoenzymatic synthesis of homogeneous N-glycoproteins carrying defined oligosaccharide ligands. J Am Chem Soc 2008; 130:13790-803. [PMID: 18803385 DOI: 10.1021/ja805044x] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An efficient chemoenzymatic method for the construction of homogeneous N-glycoproteins was described that explores the transglycosylation activity of the endo-beta-N-acetylglucosaminidase from Arthrobacter protophormiae (Endo-A) with synthetic sugar oxazolines as the donor substrates. First, an array of large oligosaccharide oxazolines were synthesized and evaluated as substrates for the Endo-A-catalyzed transglycosylation by use of ribonuclease B as a model system. The experimental results showed that Endo-A could tolerate modifications at the outer mannose residues of the Man3GlcNAc-oxazoline core, thus allowing introduction of large oligosaccharide ligands into a protein and meanwhile preserving the natural, core N-pentasaccharide (Man3GlcNAc2) structure in the resulting glycoprotein upon transglycosylation. In addition to ligands for galectins and mannose-binding lectins, azido functionality could be readily introduced at the N-pentasaccharide (Man3GlcNAc2) core by use of azido-containing Man3GlcNAc oxazoline as the donor substrate. The introduction of azido functionality permits further site-specific modifications of the resulting glycoproteins, as demonstrated by the successful attachment of two copies of alphaGal epitopes to ribonuclease B. This study reveals a broad substrate specificity of Endo-A for transglycosylation, and the chemoenzymatic method described here points to a new avenue for quick access to various homogeneous N-glycoproteins for structure-activity relationship studies and for biomedical applications.
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Affiliation(s)
- Hirofumi Ochiai
- Institute of Human Virology, Department of Biochemistry & Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA
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130
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Crich D, Yang F. Synthesis of neoglycoconjugates by the desulfurative rearrangement of allylic disulfides. J Org Chem 2008; 73:7017-27. [PMID: 18729514 PMCID: PMC2742710 DOI: 10.1021/jo8015314] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Two series of neoglycosyl donors are prepared on the basis of connection of an allylic disulfide motif to the anomeric center via a simple O-glycosyl linkage or N-glycosyl amide unit. Conjugation of both sets of donors to cysteine in peptides is demonstrated through classical disulfide exchange followed by the phosphine-mediated desulfurative allylic rearrangement resulting in neoglycopeptides characterized by a simple thioether spacer. The conjugation reaction functions in the absence of protecting groups on both the neoglycosyl donor and peptide in aqueous media at room temperature.
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Affiliation(s)
- David Crich
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, USA.
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131
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Rigbers O, Li SM. Ergot alkaloid biosynthesis in Aspergillus fumigatus. Overproduction and biochemical characterization of a 4-dimethylallyltryptophan N-methyltransferase. J Biol Chem 2008; 283:26859-68. [PMID: 18678866 DOI: 10.1074/jbc.m804979200] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The putative gene fgaMT was identified in the biosynthetic gene cluster of fumigaclavines in Aspergillus fumigatus. The coding region of fgaMT was amplified by PCR from a cDNA library, cloned into pQE60, and overexpressed in Escherichia coli. FgaMT comprises 339 amino acids with a molecular mass of about 38.1 kDa. The soluble dimeric His(6)-FgaMT was purified to near homogeneity and characterized biochemically. FgaMT was found to catalyze the N-methylation of 4-dimethylallyltryptophan in the presence of S-adenosylmethionine, resulting in the formation of 4-dimethylallyl-l-abrine, which was identified by NMR and mass spectrometry analysis. Therefore, FgaMT represents the second pathway-specific enzyme in the biosynthesis of ergot alkaloids. The enzyme did not require metal ions for its enzymatic reaction and showed a relatively high specificity toward the prenyl moiety at position C-4 of the indole ring. 4-Dimethylallyltryptophan derivatives with modification at the indole ring were also accepted by FgaMT as substrates. K(m) values for 4-dimethylallyltryptophan and S-adenosylmethionine were determined at 0.12 and 2.4 mm, respectively. The turnover number was 2.0 s(-1).
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Affiliation(s)
- Ole Rigbers
- Heinrich-Heine-Universität Düsseldorf, Institut für Pharmazeutische Biologie und Biotechnologie, Universitätsstrasse 1, D-40225 Düsseldorf, Germany
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132
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Niederhafner P, Reinis M, Sebestík J, Jezek J. Glycopeptide dendrimers, part III: a review. Use of glycopeptide dendrimers in immunotherapy and diagnosis of cancer and viral diseases. J Pept Sci 2008; 14:556-87. [PMID: 18275089 DOI: 10.1002/psc.1011] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Glycopeptide dendrimers containing different types of tumor associated-carbohydrate antigens (T(N), TF, sialyl-T(N), sialyl-TF, sialyl-Le(x), sialyl-Le(a) etc.) were used in diagnosis and therapy of different sorts of cancer. These dendrimeric structures with incorporated T-cell epitopes and adjuvants can be used as antitumor vaccines. Best results were obtained with multiantigenic vaccines, containing, e.g. five or six different TAAs. The topic of TAAs and their dendrimeric forms at molecular level are reviewed, including structure, syntheses, and biological activities. Use of glycopeptide dendrimers as antiviral vaccines against HIV and influenza is also described. Their syntheses, physico-chemical properties, and biological activities are given with many examples.
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Affiliation(s)
- Petr Niederhafner
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague 6, Czech Republic
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133
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Wrodnigg TM, Kartusch C, Illaszewicz C. The Amadori rearrangement as key reaction for the synthesis of neoglycoconjugates. Carbohydr Res 2008; 343:2057-66. [DOI: 10.1016/j.carres.2008.02.022] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2007] [Revised: 02/20/2008] [Accepted: 02/26/2008] [Indexed: 11/28/2022]
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134
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Wang LX. Chemoenzymatic synthesis of glycopeptides and glycoproteins through endoglycosidase-catalyzed transglycosylation. Carbohydr Res 2008; 343:1509-22. [PMID: 18405887 PMCID: PMC2519876 DOI: 10.1016/j.carres.2008.03.025] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2008] [Revised: 03/16/2008] [Accepted: 03/18/2008] [Indexed: 11/23/2022]
Abstract
Homogeneous glycopeptides and glycoproteins are indispensable for detailed structural and functional studies of glycoproteins. It is also fundamentally important to correct glycosylation patterns for developing effective glycoprotein-based therapeutics. This review discusses a useful chemoenzymatic method that takes advantage of the endoglycosidase-catalyzed transglycosylation to attach an intact oligosaccharide to a polypeptide in a single step, without the need for any protecting groups. The exploration of sugar oxazolines (enzymatic reaction intermediates) as donor substrates has not only expanded substrate availability, but also has significantly enhanced the enzymatic transglycosylation efficiency. Moreover, the discovery of a novel mutant with glycosynthase-like activity has made it possible to synthesize homogeneous glycoproteins with full-size natural N-glycans. Recent advances in this highly convergent chemoenzymatic approach and its application for glycopeptide and glycoprotein synthesis are highlighted.
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Affiliation(s)
- Lai-Xi Wang
- Institute of Human Virology and Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
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135
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Liu M, Borgert A, Barany G, Live D. Conformational consequences of protein glycosylation: preparation of O-mannosyl serine and threonine building blocks, and their incorporation into glycopeptide sequences derived from alpha-dystroglycan. Biopolymers 2008; 90:358-68. [PMID: 17868094 DOI: 10.1002/bip.20847] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
With the goal to investigate the structural impact of O-mannosyl glycosylation on alpha-dystroglycan, a glycoprotein that has an important role in the extracellular organization of muscle, glycopeptides derived from its mucin-like sequence have been prepared by solid-phase peptide synthesis. Two approaches have been explored to obtain needed mannosylated serine and threonine building blocks. With the alpha-carboxyl group unprotected, and with tetraaceto-1-fluoro-alpha-D-mannose as the sugar donor, the desired alpha-O-mannosyl-Fmoc-Ser/Thr formed, along with mannosyl ester isomers and the species with mannose attached to both hydroxyl and carboxyl functions. Relevant mechanistic questions and stability issues were elucidated. Alternatively, building blocks were made with the alpha-carboxyl protected/activated as the pentafluorophenyl (Pfp) ester. Glycopeptides synthesized herein contained 5-9 residues, and featured one, two, and four consecutive Ser and/or Thr residues O-glycosylated with mannose. Circular dichroism (CD) spectra for Man-containing glycopeptides recorded in water show them to be not well ordered. For one of the alpha-dystroglycan-derived sequences, the comparative conformational consequences of glycosylation by either Man or GalNAc have been examined by CD and NMR, with both methods showing a more organized structure when GalNAc is present.
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Affiliation(s)
- Mian Liu
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, USA
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136
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Kärkkäinen TS, Ravindranathan Kartha K, MacMillan D, Field RA. Iodine-mediated glycosylation en route to mucin-related glyco-aminoacids and glycopeptides. Carbohydr Res 2008; 343:1830-4. [DOI: 10.1016/j.carres.2008.03.034] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2008] [Revised: 03/20/2008] [Accepted: 03/29/2008] [Indexed: 11/30/2022]
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137
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Kremer A, Li SM. Potential of a 7-dimethylallyltryptophan synthase as a tool for production of prenylated indole derivatives. Appl Microbiol Biotechnol 2008; 79:951-61. [PMID: 18481055 DOI: 10.1007/s00253-008-1505-3] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2008] [Revised: 04/09/2008] [Accepted: 04/14/2008] [Indexed: 01/08/2023]
Abstract
Recently, a gene for a 7-dimethylallyltryptophan synthase (7-DMATS) was identified in Aspergillus fumigatus and its enzymatic function was proven biochemically. In this study, the behaviour of 7-DMATS towards aromatic substrates was investigated and compared with that of the 4-dimethylallyltryptophan synthase FgaPT2 from the same fungus. In total, 24 simple indole derivatives were tested as potential substrates for 7-DMATS. With an exception of 7-methyltryptophan, all of the substances were accepted by 7-DMATS and converted to their prenylated derivatives, indicating a more flexible substrate specificity of 7-DMATS in comparison to that of FgaPT2. The relative activities of 7-DMATS towards these substrates were from 4% to 89% of that of L-tryptophan, much higher than that of FgaPT2. Structural elucidation of the isolated enzymatic products by nuclear magnetic resonance and mass spectrometry analysis proved unequivocally the prenylation at position C7 of the indole ring. Overnight incubation with eight substances showed that the conversion ratios were in the range of 55.9% to 99.7%. This study provided an additional example that prenylated indole derivatives can be effectively produced by using the overproduced and purified 7-DMATS.
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Affiliation(s)
- Anika Kremer
- Heinrich-Heine-Universität Düsseldorf, Institut für Pharmazeutische Biologie und Biotechnologie, Universitätsstrasse 1, 40225 Düsseldorf, Germany
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138
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Li X, Danishefsky SJ. New chemistry with old functional groups: on the reaction of isonitriles with carboxylic acids--a route to various amide types. J Am Chem Soc 2008; 130:5446-8. [PMID: 18370392 DOI: 10.1021/ja800612r] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Thermolysis of isonitriles with carboxylic acids provides, in one step, N-formyl imides (see, for example, 8 + 19 --> 21). The resultant N-formyl group can be converted to N-H, NCH2OH, or NCH3. This chemistry allows for a new route for synthesizing beta-N (asparagine)-linked glycosyl amino acids.
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Affiliation(s)
- Xuechen Li
- Laboratory for Bioorganic Chemistry, Sloan-Kettering Institute for Cancer Research, 1275 York Avenue, New York, New York 10065, USA
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139
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Okamoto R, Souma S, Kajihara Y. Efficient Synthesis of MUC4 Sialylglycopeptide through the New Sialylation Using 5-Acetamido-Neuraminamide Donors. J Org Chem 2008; 73:3460-6. [DOI: 10.1021/jo702609p] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ryo Okamoto
- International Graduate School of Arts and Sciences, Yokohama City University, 22-2, Seto, Kanazawa-ku, Yokohama, 236-0027, Japan
| | - Shingo Souma
- International Graduate School of Arts and Sciences, Yokohama City University, 22-2, Seto, Kanazawa-ku, Yokohama, 236-0027, Japan
| | - Yasuhiro Kajihara
- International Graduate School of Arts and Sciences, Yokohama City University, 22-2, Seto, Kanazawa-ku, Yokohama, 236-0027, Japan
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140
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Pedersen CM, Marinescu LG, Bols M. Conformationally armed glycosyl donors: reactivity quantification, new donors and one pot reactions. Chem Commun (Camb) 2008:2465-7. [DOI: 10.1039/b801305e] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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141
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Ingale S, Buskas T, Boons GJ. Synthesis of glyco(lipo)peptides by liposome-mediated native chemical ligation. Org Lett 2007; 8:5785-8. [PMID: 17134272 DOI: 10.1021/ol062423x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Although native chemical ligation (NCL) is emerging as a powerful method for the assembly of (glyco)peptide building blocks, its applicability is reduced when peptide segments are poorly soluble in aqueous buffer. We have found that incorporating reactants in liposomes allows NCL of lipophilic peptides and lipopeptides. Furthermore, the reaction rates of liposome-mediated NCL are higher than traditional reaction conditions resulting in improved yields. [reaction: see text]
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Affiliation(s)
- Sampat Ingale
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602, USA
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142
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Steffan N, Unsöld IA, Li SM. Chemoenzymatic Synthesis of Prenylated Indole Derivatives by Using a 4-Dimethylallyltryptophan Synthase fromAspergillus fumigatus. Chembiochem 2007; 8:1298-307. [PMID: 17577899 DOI: 10.1002/cbic.200700107] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A 4-dimethylallyltryptophan synthase, FgaPT2, has been identified in the genome of Aspergillus fumigatus. In a previous study, FgaPT2 was overexpressed in Saccharomyces cerevisiae and characterized biochemically. A higher protein yield (up to 100-fold higher than that for S. cerevisiae) has now been achieved by overexpression in E. coli; this has permitted investigation into substrate specificity with alternative substances. FgaPT2 accepted 17 of 37 commercially available indole derivatives as substrates. Tryptophan derivatives that carry methyl groups at the indole ring showed a different acceptance from those with methyl groups on the side chain. 5-Hydroxytryptophan was well accepted by FgaPT2, while the halogenated derivatives were not accepted. Decarboxylation, deamination, or oxidative deamination of tryptophan, as well as replacement of the NH(2) group by OH, or of the COOH group by CH(2)COOH or CONHOH resulted in decreased but still significant enzymatic activity. None of the tested tryptophan-containing dipeptides was accepted by FgaPT2. Structural elucidation of isolated enzymatic products by NMR and MS analyses proved unequivocally that the prenylation was regioselective at position C4 of the indole ring in the presence of dimethylallyl diphosphate. Determination of the kinetic parameters revealed that L-tryptophan was accepted as the best substrate by the enzyme, followed by 5-,6-,7-methyltryptophan and L-abrine. The enzymatic rate constant (k(cat) K(m) (-1)) of nine selected substrates were found to be about 1.0 to 6.5 % of that for L-tryptophan. Overnight incubation with eight substances showed that the conversion ratio to their prenylated derivatives was in the range 32.5 to 99.7 %. This provides evidence that 4-dimethylallylated indole derivatives can be produced by chemoenzymatic synthesis with FgaPT2.
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Affiliation(s)
- Nicola Steffan
- Heinrich-Heine-Universität Düsseldorf, Institut für Pharmazeutische Biologie und Biotechnologie, Universitätsstrasse 1, 40225 Düsseldorf, Germany
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143
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Abstract
Glycosylation is a common post-translational modification of proteins. Although its significance in biological system is well recognized, approaches to analyze carbohydrate function are limited. This is because of difficulty in obtaining homogeneous glycoproteins from natural sources. Due to the progress of the carbohydrate and peptide chemistry, syntheses of various homogeneous glycopeptides and glycoproteins, which are suitable for biological studies, have been achieved by chemical means. In this review, we briefly summarize recent advances in the field of glycopeptide synthesis after 1999.
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Affiliation(s)
- Hironobu Hojo
- Department of Applied Biochemistry, Institute of Glycotechnology, Tokai University, Kitakaname 1117, Hiratsuka, Kanagawa, Japan.
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144
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Abstract
Therapeutic vaccines derived from carbohydrate antigen-adjuvant combinations are a promising approach for cancer immunotherapy. One of the critical limitations in this area is access to sufficient quantities of tumour-associated carbohydrate antigens and glycoconjugate adjuvants. At present, availability of the complex oligosaccharide constructs that are needed for the systematic design and evaluation of novel vaccine formulations relies on de novo chemical synthesis. The use of both state-of-the-art and emerging glycosylation technologies has led to significant advances in this field, allowing the clinical exploration of carbohydrate-based antigens in the treatment of cancer.
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Affiliation(s)
- Danica P Galonić
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.
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145
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André S, Maljaars CEP, Halkes KM, Gabius HJ, Kamerling JP. Discovery of galectin ligands in fully randomized combinatorial one-bead-one-compound (glyco)peptide libraries. Bioorg Med Chem Lett 2007; 17:793-8. [PMID: 17095217 DOI: 10.1016/j.bmcl.2006.10.067] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2006] [Revised: 10/24/2006] [Accepted: 10/24/2006] [Indexed: 12/15/2022]
Abstract
The involvement of human lectins (galectins) in disease progression accounts for the interest to design potent inhibitors. Three fully randomized hexa(glyco)peptide libraries were prepared using the portion mixing method combined with ladder synthesis. On-bead screening with fluorescently labelled galectin-1 and -3 yielded a series of lead structures, whose inhibitory activity on carbohydrate-dependent galectin binding was tested in solution by solid-phase and cell assays. The various data obtained define the library approach as a facile route for the discovery of selective (glyco)peptide-based galectin inhibitors.
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Affiliation(s)
- Sabine André
- Institute of Physiological Chemistry, Faculty of Veterinary Medicine, Ludwig-Maximilians-University Munich, Veterinärstr. 13, 80539 Munich, Germany
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146
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Timmer MSM, Stocker BL, Seeberger PH. Probing glycomics. Curr Opin Chem Biol 2007; 11:59-65. [PMID: 17208037 DOI: 10.1016/j.cbpa.2006.11.040] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2006] [Accepted: 11/27/2006] [Indexed: 01/24/2023]
Abstract
The study of protein-carbohydrate interactions is one central theme of glycomics research. The challenges encountered when investigating these interactions have resulted in an approach that studies saccharides through the enzymes that process them. Proteins and their function are often probed by manipulating the genes that encode them. Efforts in proteoglycomics exploring protein-binding properties and the enzymatic modification of carbohydrates have intensified, and synthetic tools, including activity- and affinity-based probes, have enhanced our understanding of the roles of carbohydrates in biology.
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Affiliation(s)
- Mattie S M Timmer
- Laboratory for Organic Chemistry, Swiss Federal Institute of Technology (ETH) Zürich, Wolfgang-Pauli Strasse 10, 8093 Zurich, Switzerland
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147
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