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Li T, Spruit CM, Wei N, Liu L, Wolfert MA, de Vries RP, Boons GJ. Chemoenzymatic Synthesis of Tri-antennary N-Glycans Terminating in Sialyl-Lewis x Reveals the Importance of Glycan Complexity for Influenza A Virus Receptor Binding. Chemistry 2024; 30:e202401108. [PMID: 38567703 PMCID: PMC11156558 DOI: 10.1002/chem.202401108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Indexed: 05/09/2024]
Abstract
Sialyl-Lewisx (SLex) is involved in immune regulation, human fertilization, cancer, and bacterial and viral diseases. The influence of the complex glycan structures, which can present SLex epitopes, on binding is largely unknown. We report here a chemoenzymatic strategy for the preparation of a panel of twenty-two isomeric asymmetrical tri-antennary N-glycans presenting SLex-Lex epitopes on either the MGAT4 or MGAT5 arm that include putative high-affinity ligands for E-selectin. The N-glycans were prepared starting from a sialoglycopeptide isolated from egg yolk powder and took advantage of inherent substrate preferences of glycosyltransferases and the use of 5'-diphospho-N-trifluoracetylglucosamine (UDP-GlcNHTFA) that can be transferred by branching N-acetylglucosaminyltransferases to give, after base treatment, GlcNH2-containing glycans that temporarily disable an antenna from enzymatic modification. Glycan microarray binding studies showed that E-selectin bound equally well to linear glycans and tri-antennary N-glycans presenting SLex-Lex. On the other hand, it was found that hemagglutinins (HA) of H5 influenza A viruses (IAV) preferentially bound the tri-antennary N-glycans. Furthermore, several H5 HAs preferentially bound to N-glycan presenting SLex on the MGAT4 arm. SLex is displayed in the respiratory tract of several avian species, demonstrating the relevance of investigating the binding of, among others IAVs, to complex N-glycans presenting SLex.
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Affiliation(s)
- Tiehai Li
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
- Present address: Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, P. R. China
| | - Cindy M Spruit
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, 3584 CG, Utrecht, The Netherlands
| | - Na Wei
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
| | - Lin Liu
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
| | - Margreet A Wolfert
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, 3584 CG, Utrecht, The Netherlands
| | - Robert P de Vries
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, 3584 CG, Utrecht, The Netherlands
| | - Geert-Jan Boons
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, 3584 CG, Utrecht, The Netherlands
- Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, The Netherlands
- Chemistry Department, University of Georgia, Athens, GA 30602, USA
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2
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Dhara D, Dhara A, Murphy PV, Mulard LA. Protecting group principles suited to late stage functionalization and global deprotection in oligosaccharide synthesis. Carbohydr Res 2022; 521:108644. [PMID: 36030632 DOI: 10.1016/j.carres.2022.108644] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 07/28/2022] [Accepted: 07/31/2022] [Indexed: 11/02/2022]
Abstract
Chemical synthesis is a powerful tool to access homogeneous complex glycans, which relies on protecting group (PG) chemistry. However, the overall efficiency of chemical glycan assembly is still low when compared to oligonucleotide or oligopeptide synthesis. There have been many contributions giving rise to collective improvement in carbohydrate synthesis that includes PG manipulation and stereoselective glycoside formation and some of this chemistry has been transferred to the solid phase or adapted for programmable one pot synthesis approaches. However, after all glycoside bond formation reactions are completed, the global deprotection (GD) required to give the desired target OS can be challenging. Difficulties observed in the removal of permanent PGs to release the desired glycans can be due to the number and diversity of PGs present in the protected OSs, nature and structural complexity of glycans, etc. Here, we have reviewed the difficulties associated with the removal of PGs from densely protected OSs to obtain their free glycans. In particularly, this review focuses on the challenges associated with hydrogenolysis of benzyl groups, saponification of esters and functional group interconversion such as oxidation/reduction that are commonly performed in GD stage. More generally, problems observed in the removal of permanent PGs is reviewed herein, including benzyl, acyl (levulinoyl, acetyl), N-trichloroacetyl, N-2,2,2-trichloroethoxycarbonyl, N-phthaloyl etc. from a number of fully protected OSs to release the free sugar, that have been previously reported in the literature.
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Affiliation(s)
- Debashis Dhara
- Institut Pasteur, Université Paris Cité, CNRS UMR 3523, Unité de Chimie des Biomolécules, 25-28 rue du Dr Roux, 75015, Paris, France; School of Biological and Chemical Sciences, NUI Galway, University Road, Galway, H91 TK33, Ireland.
| | - Ashis Dhara
- School of Biological and Chemical Sciences, NUI Galway, University Road, Galway, H91 TK33, Ireland
| | - Paul V Murphy
- School of Biological and Chemical Sciences, NUI Galway, University Road, Galway, H91 TK33, Ireland; SSPC - The Science Foundation Ireland Research Centre for Pharmaceuticals, NUI Galway, University Road, Galway, H91 TK33, Ireland
| | - Laurence A Mulard
- Institut Pasteur, Université Paris Cité, CNRS UMR 3523, Unité de Chimie des Biomolécules, 25-28 rue du Dr Roux, 75015, Paris, France
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3
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Li W, Yu B. Temporary ether protecting groups at the anomeric center in complex carbohydrate synthesis. Adv Carbohydr Chem Biochem 2020; 77:1-69. [PMID: 33004110 DOI: 10.1016/bs.accb.2019.10.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The synthesis of a carbohydrate building block usually starts with introduction of a temporary protecting group at the anomeric center and ends with its selective cleavage for further transformation. Thus, the choice of the anomeric temporary protecting group must be carefully considered because it should retain intact during the whole synthetic manipulation, and it should be chemoselectively removable without affecting other functional groups at a late stage in the synthesis. Etherate groups are the most widely used temporary protecting groups at the anomeric center, generally including allyl ethers, MP (p-methoxyphenyl) ethers, benzyl ethers, PMB (p-methoxybenzyl) eithers, and silyl ethers. This chapter provides a comprehensive review on their formation, cleavage, and applications in the synthesis of complex carbohydrates.
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Affiliation(s)
- Wei Li
- Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, China.
| | - Biao Yu
- State Key Laboratory of Bio-organic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China.
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4
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Enugala R, Carvalho LCR, Dias Pires MJ, Marques MMB. Stereoselective Glycosylation of Glucosamine: The Role of the
N
‐Protecting Group. Chem Asian J 2012; 7:2482-501. [DOI: 10.1002/asia.201200338] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Indexed: 12/17/2022]
Affiliation(s)
- Ramu Enugala
- Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica 2829‐516 Caparica (Portugal), Fax: (+351) 21‐294‐8550
| | - Luísa C. R. Carvalho
- Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica 2829‐516 Caparica (Portugal), Fax: (+351) 21‐294‐8550
| | - Marina J. Dias Pires
- Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica 2829‐516 Caparica (Portugal), Fax: (+351) 21‐294‐8550
| | - M. Manuel B. Marques
- Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica 2829‐516 Caparica (Portugal), Fax: (+351) 21‐294‐8550
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5
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Lichtenthaler FW. 2-Oxoglycosyl ("ulosyl") and 2-oximinoglycosyl bromides: versatile donors for the expedient assembly of oligosaccharides with β-D-mannose, β-L-rhamnose, N-acetyl-β-D-mannosamine, and N-acetyl-β-D-mannosaminuronic acid units. Chem Rev 2011; 111:5569-609. [PMID: 21751781 DOI: 10.1021/cr100444b] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Frieder W Lichtenthaler
- Clemens-Schöpf-Institut für Organische Chemie, Technische Universität Darmstadt, D-64287 Darmstadt, Germany.
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6
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Miermont A, Zeng Y, Jing Y, Ye XS, Huang X. Syntheses of Lewis(x) and dimeric Lewis(x): construction of branched oligosaccharides by a combination of preactivation and reactivity based chemoselective one-pot glycosylations. J Org Chem 2007; 72:8958-61. [PMID: 17939723 PMCID: PMC2593850 DOI: 10.1021/jo701694k] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Two asymmetrically branched oligosaccharides, LewisX and dimeric LewisX, were assembled in one pot with high yields and exclusive regio- and stereoselectivities. p-Tolyl thioglycosides were utilized as the sole type of building blocks, thus simplifying the overall synthetic design. The reactivity-independent nature of the preactivation based method allows modular assembly of the dimeric LewisX octasaccharide without the need for tedious protective group manipulation to achieve exact anomeric reactivities.
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Affiliation(s)
- Adeline Miermont
- Department of Chemistry, The University of Toledo, 2801 W. Bancroft Street, MS 602, Toledo, Ohio 43606
| | - Youlin Zeng
- Department of Chemistry, The University of Toledo, 2801 W. Bancroft Street, MS 602, Toledo, Ohio 43606
| | - Yuqing Jing
- Department of Chemistry, The University of Toledo, 2801 W. Bancroft Street, MS 602, Toledo, Ohio 43606
| | - Xin-shan Ye
- The State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Xue Yuan Rd. 38, Beijing 100083, China
| | - Xuefei Huang
- Department of Chemistry, The University of Toledo, 2801 W. Bancroft Street, MS 602, Toledo, Ohio 43606
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Naruchi K, Hamamoto T, Kurogochi M, Hinou H, Shimizu H, Matsushita T, Fujitani N, Kondo H, Nishimura SI. Construction and Structural Characterization of Versatile Lactosaminoglycan-Related Compound Library for the Synthesis of Complex Glycopeptides and Glycosphingolipids. J Org Chem 2006; 71:9609-21. [PMID: 17168577 DOI: 10.1021/jo0617161] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have established a facile and efficient protocol for the preparative-scale synthesis of various compound libraries related to lactosaminoglycans: cell surface oligosaccharides composed of N-acetyllactosamine as a repeating disaccharide unit, based on chemical and enzymatic approaches. Substrate specificity and feasibility of a bacterial glycosyltransferase, Neisseria meningitidis beta1,3-N-acetylglucosaminyltransferase (LgtA), were investigated in order to synthesize various key intermediates suited for the construction of mammalian O-glycopeptides and glycosphingolipids containing poly-N-acetyllactosamine structures. Recombinant LgtA exhibited the highest glycosyltransferase activity with strongly basic conditions (pH = 10, glycine-NaOH buffer) and a broad range of optimal temperatures from 20 to 30 degrees C. Interestingly, it was found that LgtA discriminates L-serine and L-threonine and functions both as a core-1 beta1,3-N-acetylglucosaminyltransferase and core-2 beta1,3-N-acetylglucosaminyltransferase toward Fmoc-Ser derivatives, while LgtA showed only core-2 beta1,3-N-acetylglucosaminyltransferase activity in the presence of Fmoc-Thr derivatives. Combined use of LgtA with human beta1,4-galactosyltransferase allowed for controlled sugar extension reactions from synthetic sugar amino acids and gave synthetic lactosaminoglycans, such as a decasaccharide derivative, Galbeta(1 --> 4)GlcNAcbeta(1 --> 3)Galbeta(1 --> 4)GlcNAcbeta(1 --> 3)Galbeta(1 --> 4)GlcNAcbeta(1 --> 3)Galbeta(1 --> 4)GlcNAcbeta(1 --> 6)[Galbeta(1 --> 3)]GalNAcalpha1 --> Fmoc-Ser-OH (6), and a dodecasaccharide derivative, Galbeta(1 --> 4)GlcNAcbeta(1 --> 3)Galbeta(1 --> 4)GlcNAcbeta(1 --> 3)Galbeta(1 --> 4)GlcNAcbeta(1 --> 6)[Galbeta(1 --> 4)GlcNAcbeta(1 --> 3)Galbeta(1 --> 4)GlcNAcbeta(1 --> 3)Galbeta(1 --> 3)]GalNAcalpha1 --> Fmoc-Ser-OH (9). A partially protected pentasaccharide intermediate, GlcNAcbeta(1 --> 3)Galbeta(1 --> 4)GlcNAcbeta(1 --> 6)[Galbeta(1 --> 3)]GalNAcalpha1 --> Fmoc-Thr-OH (11), was applied for the microwave-assisted solid-phase synthesis of a MUC1-related glycopeptide 19 (MW = 2610.1). The findings suggest that this sugar extension strategy can be employed for the modification of lactosyl ceramide mimetic polymers to afford convenient precursors for the synthesis of various glycosphingolipids.
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Affiliation(s)
- Kentarou Naruchi
- Division of Advanced Chemical Biology, Graduate School of Advanced Life Science, Frontier Research Center for the Post-Genome Science and Technology, Hokkaido University, N21, W11, Sapporo 001-0021, Japan
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8
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Affiliation(s)
- Peter Welzel
- Institut für Organische Chemie, Universität Leipzig, Germany.
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9
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Chandrasekaran EV, Xue J, Xia J, Chawda R, Piskorz C, Locke RD, Neelamegham S, Matta KL. Analysis of the specificity of sialyltransferases toward mucin core 2, globo, and related structures. identification of the sialylation sequence and the effects of sulfate, fucose, methyl, and fluoro substituents of the carbohydrate chain in the biosynthesis of selectin and siglec ligands, and novel sialylation by cloned alpha2,3(O)sialyltransferase. Biochemistry 2006; 44:15619-35. [PMID: 16300412 DOI: 10.1021/bi050246m] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Sialic acids are key determinants in many carbohydrates involved in biological recognition. We studied the acceptor specificities of three cloned sialyltransferases (STs) [alpha2,3(N)ST, alpha2,3(O)ST, and alpha2,6(N)ST] and another alpha2,3(O)ST present in prostate cancer cell LNCaP toward mucin core 2 tetrasaccharide [Galbeta1,4GlcNAcbeta1,6(Galbeta1,3)GalNAcalpha-O-Bn] and Globo [Galbeta1,3GalNAcbeta1,3Galalpha-O-Me] structures containing sialyl, fucosyl, sulfo, methyl, or fluoro substituents by identifying the products by electrospray ionization tandem mass spectral analysis and other biochemical methods. The Globo precursor was an efficient acceptor for both alpha2,3(N)ST and alpha2,3(O)ST, whereas only alpha2,3(O)ST used its deoxy analogue (d-Fucbeta1,3GalNAcbeta1,3-Gal-alpha-O-Me); 2-O-MeGalbeta1,3GlcNAc and 4-OMeGalbeta1,4GlcNAc were specific acceptors for alpha2,3(N)ST. Other major findings of this study include: (i) alpha2,3 sialylation of beta1,3Gal in mucin core 2 can proceed even after alpha1,3 fucosylation of beta1,6-linked LacNAc. (ii) Sialylation of beta1,3Gal must precede the sialylation of beta1,4Gal for favorable biosynthesis of mucin core 2 compounds. (iii) alpha2,3 sialylation of the 6-O-sulfoLacNAc moiety in mucin core 2 (e.g., GlyCAM-1) is facilitated when beta1,3Gal has already been alpha2,3 sialylated. (iv) alpha2,6(N)ST was absolutely specific for the beta1,4Gal in mucin core 2. Either alpha1,3 fucosylation or 6-O-sulfation of the GlcNAc moiety reduced the activity. Sialylation of beta1,3Gal in addition to 6-O-sulfation of GlcNAc moiety abolished the activity. (v) Prior alpha2,3 sialylation or 3-O-sulfation of beta1,3Gal would not affect alpha2,6 sialylation of Galbeta1,4GlcNAc of mucin core 2. (vi) A 3- or 4-fluoro substituent in beta1,4Gal resulted in poor acceptors for the cloned alpha2,6(N)ST and alpha2,3(N)ST, whereas 4-fluoro- or 4-OMe-Galbeta1,3GalNAcalpha was a good acceptor for cloned alpha2,3(O)ST. (vii) 4-O-Methylation of beta1,4Gal abolished the acceptor ability toward alpha2,6(N)ST but increased the acceptor efficiency considerably toward alpha2,3(N)ST. (viii) Just like LNCaPalpha1,2-FT and Gal-3-O-sulfotransferase T2, the cloned alpha2,3(N)ST which modifies terminal Gal in Galbeta1,4GlcNAc also efficiently utilizes the terminal beta1,3Gal in the Globo backbone. Utilization of C-3 blocked compounds such as 3-O-sulfo-Galbeta1,3GalNAcbeta1,3Galalpha-OMe as acceptors by cloned alpha2,3(O)ST and analyses of the resulting products by lectin chromatography and mass spectrometry indicate that alpha2,3(O)ST is capable of attaching NeuAc to another position in C-3-substituted beta1,3Gal.
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Affiliation(s)
- E V Chandrasekaran
- Cancer Biology, Roswell Park Cancer Institute, Elm & Carlton Streets, Buffalo, New York 14263, USA
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Mong TKK, Huang CY, Wong CH. A new reactivity-based one-pot synthesis of N-acetyllactosamine oligomers. J Org Chem 2003; 68:2135-42. [PMID: 12636372 DOI: 10.1021/jo0206420] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Poly-N-acetyllactosamine oligomer is a type-2 glycan core from which a number of important bioactive glycoconjugates are assembled in vivo. Development of an effective synthesis of N-acetyllactosamine oligomers will therefore provide a new chemoenzymatic entry to this class of complex saccharides. This paper describes the design and synthesis of thioglycoside building blocks, determination of their relative reactivity values, and demonstration of their use in the programmable one-pot synthesis of various N-acetyllactosamine oligomers. Through a combination of segment condensation, the strategy allows for the preparation of larger oligosaccharides with minimal protecting group manipulation, as illustrated in the synthesis of an octasaccharide in a very short period of time.
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Affiliation(s)
- Tony K-K Mong
- Department of Chemistry and the Skaggs institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA
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11
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Marcaurelle LA, Bertozzi CR. Chemoselective elaboration of O-linked glycopeptide mimetics by alkylation of 3-thioGalNAc. J Am Chem Soc 2001; 123:1587-95. [PMID: 11456757 DOI: 10.1021/ja003713q] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A critical branch point in mucin-type oligosaccharides is the beta 1-->3 glycosidic linkage to the core alpha-N-acetylgalactosamine (GalNAc) residue. We report here a strategy for the synthesis of O-linked glycopeptide analogues that replaces this linkage with a thioether amenable to construction by chemoselective ligation. The key building block was a 2-azido-3-thiogalactose-Thr analogue that was incorporated into a peptide by fluorenylmethoxycarbonyl (Fmoc)-based solid-phase peptide synthesis. Higher order oligosaccharides were readily generated by alkylation of the corresponding 3-thioGalNAc with N-bromoacetamido sugars. The rapid assembly of "core 1"and "core 3" O-linked glycopeptide mimetics was accomplished in this fashion.
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Affiliation(s)
- L A Marcaurelle
- Center for New Directions in Organic Synthesis, Department of Chemistry, University of California, Berkeley, California 94720, USA
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12
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Pykäri M, Toivonen S, Natunen J, Niemela R, Salminen H, Aitio O, Ekström M, Parmanne P, Välimäki M, Alais J, Augé C, Lowe JB, Renkonen O, Renkonen R. The acceptor and site specificity of alpha 3-fucosyltransferase V. High reactivity of the proximal and low of the distal galbeta 1-4GlcNAc unit in i-type polylactosamines. J Biol Chem 2000; 275:40057-63. [PMID: 11007797 DOI: 10.1074/jbc.m007922200] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We report here on in vitro acceptor and site specificity of recombinant alpha3-fucosyltransferase V (Fuc-TV) with 40 oligosaccharide acceptors. Galbeta1-4GlcNAc (LN) and GalNAcbeta1-4GlcNAc (LDN) reacted rapidly; Galbeta1-3GlcNAc (LNB) reacted moderately, and GlcNAcbeta1-4GlcNAc (N, N'-diacetyl-chitobiose) reacted slowly yet distinctly. In neutral and terminally alpha3-sialylated polylactosamines of i-type, the reducing end LN unit reacted rapidly and the distal (sialyl)LN group very slowly; the midchain LNs revealed intermediate reactivities. The data suggest that a distal LN neighbor enhances but a proximal LN neighbor reduces the reactivity of the midchain LNs. This implies that Fuc-TV may bind preferably the tetrasaccharide sequence Galbeta1-4GlcNAcbeta1-3Galbeta1-4GlcNAc for transfer at the underlined monosaccharide. Terminal alpha3-sialylation of i-type polylactosamines almost doubled the reactivities of the LN units at all positions of the chains. We conclude that, in comparison with human Fuc-TIV and Fuc-TIX, Fuc-TV reacted with a highly distinct site specificity with i-type polylactosamines. The Fuc-TV reactivity of free LNB resembled that of LNBbeta1-3'R of a polylactosamine, contrasting strongly with the dissimilarity of the reactivities of the analogous pair of LN and LNbeta1-3'R. This observation supports the notion that LN and LNB may be functionally bound at distinct sites on Fuc-TV surface. Our data show that Fuc-TV worked well with a very wide range of LN-glycans, showing weak reactivity only with distal (sialyl)LN units of i-type polylactosamines, biantennary N-glycans, and I branches of polylactosamines.
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Affiliation(s)
- M Pykäri
- Institute of Biotechnology, University of Helsinki, P.O. Box 56, 00014 Helsinki, Finland
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13
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Koeller KM, Wong CH. Synthesis of complex carbohydrates and glycoconjugates: enzyme-based and programmable one-pot strategies. Chem Rev 2000; 100:4465-94. [PMID: 11749355 DOI: 10.1021/cr990297n] [Citation(s) in RCA: 347] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- K M Koeller
- Department of Chemistry, The Scripps Research Institute and Skaggs Institute for Chemical Biology, 10550 North Torrey Pines Road, La Jolla, California 92037
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