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Sukhran Y, Alshanski I, Filiba O, Mackintosh MJ, Schapiro I, Hurevich M. Unexpected Nucleophile Masking in Acyl Transfer to Sterically Crowded and Conformationally Restricted Galactosides. J Org Chem 2023. [PMID: 37269328 DOI: 10.1021/acs.joc.3c00878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Design and synthesis of orthogonally protected monosaccharide building blocks are crucial for the preparation of well-defined oligosaccharides in a stereo- and regiocontrolled manner. Selective introduction of protecting groups to partially protected monosaccharides is nontrivial due to the often unpredictable electronic, steric, and conformational effects of the substituents. Abolished reactivity toward a commonly used Lewis base-catalyzed acylation of O-2 was observed in conformationally restricted 4,6-O-benzylidene-3-O-Nap galactoside. Investigation of analogous systems, crystallographic characterization, and quantum chemical calculations highlighted the overlooked conformational and steric considerations, the combination of which produces a unique passivity of the 2-OH nucleophile. Evaluating the role of electrophile counterion and auxiliary base in the acylation of the sterically crowded and conformationally restricted galactoside system revealed an alternative Brønsted base-driven reaction pathway via nucleophilic activation. Insights gained from this model system were utilized to access the target galactoside intermediate within the envisioned synthetic route. The acylation strategy described herein can be implemented in future syntheses of key monomeric building blocks with unique protecting group hierarchies.
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Affiliation(s)
- Yonatan Sukhran
- The Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Israel Alshanski
- The Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Ofer Filiba
- Fritz Haber Center for Molecular Dynamics, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Megan J Mackintosh
- Fritz Haber Center for Molecular Dynamics, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Igor Schapiro
- Fritz Haber Center for Molecular Dynamics, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Mattan Hurevich
- The Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
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Speciale I, Notaro A, Abergel C, Lanzetta R, Lowary TL, Molinaro A, Tonetti M, Van Etten JL, De Castro C. The Astounding World of Glycans from Giant Viruses. Chem Rev 2022; 122:15717-15766. [PMID: 35820164 PMCID: PMC9614988 DOI: 10.1021/acs.chemrev.2c00118] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Indexed: 12/12/2022]
Abstract
Viruses are a heterogeneous ensemble of entities, all sharing the need for a suitable host to replicate. They are extremely diverse, varying in morphology, size, nature, and complexity of their genomic content. Typically, viruses use host-encoded glycosyltransferases and glycosidases to add and remove sugar residues from their glycoproteins. Thus, the structure of the glycans on the viral proteins have, to date, typically been considered to mimick those of the host. However, the more recently discovered large and giant viruses differ from this paradigm. At least some of these viruses code for an (almost) autonomous glycosylation pathway. These viral genes include those that encode the production of activated sugars, glycosyltransferases, and other enzymes able to manipulate sugars at various levels. This review focuses on large and giant viruses that produce carbohydrate-processing enzymes. A brief description of those harboring these features at the genomic level will be discussed, followed by the achievements reached with regard to the elucidation of the glycan structures, the activity of the proteins able to manipulate sugars, and the organic synthesis of some of these virus-encoded glycans. During this progression, we will also comment on many of the challenging questions on this subject that remain to be addressed.
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Affiliation(s)
- Immacolata Speciale
- Department
of Agricultural Sciences, University of
Napoli, Via Università
100, 80055 Portici, Italy
| | - Anna Notaro
- Department
of Agricultural Sciences, University of
Napoli, Via Università
100, 80055 Portici, Italy
- Centre
National de la Recherche Scientifique, Information Génomique
& Structurale, Aix-Marseille University, Unité Mixte de Recherche
7256, IMM, IM2B, 13288 Marseille, Cedex 9, France
| | - Chantal Abergel
- Centre
National de la Recherche Scientifique, Information Génomique
& Structurale, Aix-Marseille University, Unité Mixte de Recherche
7256, IMM, IM2B, 13288 Marseille, Cedex 9, France
| | - Rosa Lanzetta
- Department
of Chemical Sciences, University of Napoli, Via Cintia 4, 80126 Napoli, Italy
| | - Todd L. Lowary
- Institute
of Biological Chemistry, Academia Sinica, Academia Road, Section 2, Nangang 11529, Taipei, Taiwan
| | - Antonio Molinaro
- Department
of Chemical Sciences, University of Napoli, Via Cintia 4, 80126 Napoli, Italy
| | - Michela Tonetti
- Department
of Experimental Medicine and Center of Excellence for Biomedical Research, University of Genova, 16132 Genova, Italy
| | - James L. Van Etten
- Nebraska
Center for Virology, University of Nebraska, Lincoln, Nebraska 68583-0900, United States
- Department
of Plant Pathology, University of Nebraska, Lincoln, Nebraska 68583-0722, United States
| | - Cristina De Castro
- Department
of Agricultural Sciences, University of
Napoli, Via Università
100, 80055 Portici, Italy
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QIN CJ, DING MR, TIAN GZ, ZOU XP, FU JJ, HU J, YIN J. Chemical approaches towards installation of rare functional groups in bacterial surface glycans. Chin J Nat Med 2022; 20:401-420. [DOI: 10.1016/s1875-5364(22)60177-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Indexed: 11/24/2022]
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Sun T, Zhang Y, Meng Y, Wang Y, Zhu Q, Jiang Y, Liu S. Photoredox-Copper Dual-Catalyzed Site-Selective O-Alkylation of Glycosides. CHINESE J ORG CHEM 2022. [DOI: 10.6023/cjoc202112029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Crich D. En Route to the Transformation of Glycoscience: A Chemist's Perspective on Internal and External Crossroads in Glycochemistry. J Am Chem Soc 2021; 143:17-34. [PMID: 33350830 PMCID: PMC7856254 DOI: 10.1021/jacs.0c11106] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Carbohydrate chemistry is an essential component of the glycosciences and is fundamental to their progress. This Perspective takes the position that carbohydrate chemistry, or glycochemistry, has reached three crossroads on the path to the transformation of the glycosciences, and illustrates them with examples from the author's and other laboratories. The first of these potential inflexion points concerns the mechanism of the glycosylation reaction and the role of protecting groups. It is argued that the experimental evidence supports bimolecular SN2-like mechanisms for typical glycosylation reactions over unimolecular ones involving stereoselective attack on naked glycosyl oxocarbenium ions. Similarly, it is argued that the experimental evidence does not support long-range stereodirecting participation of remote esters through bridged bicyclic dioxacarbenium ions in organic solution in the presence of typical counterions. Rational design and improvement of glycosylation reactions must take into account the roles of the counterion and of concentration. A second crossroads is that between mainstream organic chemistry and glycan synthesis. The case is made that the only real difference between glycan and organic synthesis is the formation of C-O rather than C-C bonds, with diastereocontrol, strategy, tactics, and elegance being of critical importance in both areas: mainstream organic chemists should feel comfortable taking this fork in the road, just as carbohydrate chemists should traveling in the opposite direction. A third crossroads is that between carbohydrate chemistry and medicinal chemistry, where there are equally many opportunities for traffic in either direction. The glycosciences have advanced enormously in the past decade or so, but creativity, input, and ingenuity of scientists from all fields is needed to address the many sophisticated challenges that remain, not the least of which is the development of a broader and more general array of stereospecific glycosylation reactions.
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Affiliation(s)
- David Crich
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 250 West Green Street, Athens, Georgia 30602, United States
- Department of Chemistry, University of Georgia, 140 Cedar Street, Athens, Georgia 30602, United States
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, Georgia 30602, United States
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Dimakos V, Taylor MS. Site-Selective Functionalization of Hydroxyl Groups in Carbohydrate Derivatives. Chem Rev 2018; 118:11457-11517. [DOI: 10.1021/acs.chemrev.8b00442] [Citation(s) in RCA: 148] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Victoria Dimakos
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6, Canada
| | - Mark S. Taylor
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6, Canada
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De Ricco R, Ventura CL, Carboni F, Saksena R, Kováč P, Adamo R. Structure-Immunogenicity Relationship of α- and β-Tetrasaccharide Glycoforms from Bacillus anthracis Exosporium and Fragments Thereof. Molecules 2018; 23:molecules23082079. [PMID: 30127242 PMCID: PMC6222408 DOI: 10.3390/molecules23082079] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 08/01/2018] [Accepted: 08/17/2018] [Indexed: 11/16/2022] Open
Abstract
The tetrasaccharide (2-O-methyl-4-(3-hydroxy-3-methylbutamido)-4,6-dideoxy-α-d-glucopyranosyl-(1→3)-α-l-rhamnopyranosyl-(1→3)-α-l-rhamnopyranosyl-(1→2)-l-rhamnopyranose) from the major exosporium protein (BclA) of Bacillus anthracis has been proposed as a target for development of diagnostics and immune therapy or prophylaxis. While the immunodominant character of the anthrose residue has been previously elucidated, the role of the stereochemical configuration of the downstream rhamnose is unknown. Because the linkage of this residue to the GlcNAc bridging the glycan and the protein is lost during isolation of the tetrasaccharide, its α- and β-glycoforms have been synthesized. Herein, we prepared neoglycoconjugates from a series of fragments of the tetrasaccharide, including the complete α- and β-tetrasaccharide glycoforms, a 2-demethoxylated version of the α-tetrasaccharide, and the α- and β-trirhamnosides and CRM197. By immunization of mice, we showed that the anti α- and β-tetrasaccharide serum equally recognized both glycoforms. In contrast the sera produced following immunization with the α- and β-trirhamnoside fragments exhibited higher recognition for their own antigens than for their anomeric counterparts. The anti α- and β-tetrasaccharide sera recognized Sterne spores in a comparable fashion. ΔBclA spores not expressing the major exosporium protein were also recognized by the same sera, while mutants that produced the carbohydrate antigen with deletion of either rhamnose or anthrose were not. The tetrasaccharide could, therefore, be expressed in proteins other than BlcA. This work proves that α- and β-tetrasaccharide are equally potent immunogens.
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Affiliation(s)
| | - Christy L Ventura
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA.
| | | | - Rina Saksena
- NIDDK, LBC, National Institutes of Health, Bethesda, MD 20892-0815, USA.
| | - Pavol Kováč
- NIDDK, LBC, National Institutes of Health, Bethesda, MD 20892-0815, USA.
| | - Roberto Adamo
- GSK, Research Centre, via Fiorentina 1, 53100 Siena, Italy.
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Sano R, Kudo A, Tsubogo T, Uchiro H. Phenylselenylation of Ethers using Diphenyl Diselenide-Tributylphosphine-Molecular Oxygen System under Mild Reaction Conditions. ASIAN J ORG CHEM 2018. [DOI: 10.1002/ajoc.201800026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Ryota Sano
- Faculty of Pharmaceutical Sciences; Tokyo University of Science; 2641 Yamazaki Noda-shi Chiba 278-8510 Japan
| | - Asaki Kudo
- Faculty of Pharmaceutical Sciences; Tokyo University of Science; 2641 Yamazaki Noda-shi Chiba 278-8510 Japan
| | - Tetsu Tsubogo
- Faculty of Pharmaceutical Sciences; Tokyo University of Science; 2641 Yamazaki Noda-shi Chiba 278-8510 Japan
| | - Hiromi Uchiro
- Faculty of Pharmaceutical Sciences; Tokyo University of Science; 2641 Yamazaki Noda-shi Chiba 278-8510 Japan
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Jakas A, Perc M, Suć J, Rodriguez MC, Cudic M, Cudic P. Synthesis of anthrose lipidic derivative as mimic of B. anthracis BclA glycoprotein for use in ELISA-like binding assays. J Carbohydr Chem 2016. [DOI: 10.1080/07328303.2016.1139124] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Andreja Jakas
- Division of Organic Chemistry and Biochemistry, Rudjer Bošković Institute, Zagreb, Croatia
| | - Milica Perc
- Division of Organic Chemistry and Biochemistry, Rudjer Bošković Institute, Zagreb, Croatia
| | - Josipa Suć
- Division of Organic Chemistry and Biochemistry, Rudjer Bošković Institute, Zagreb, Croatia
| | - Maria C. Rodriguez
- Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, FL, USA
| | - Mare Cudic
- Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, FL, USA
| | - Predrag Cudic
- Torrey Pines Institute for Molecular Studies, Port St. Lucie, FL, USA
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Maes E, Krzewinski F, Garenaux E, Lequette Y, Coddeville B, Trivelli X, Ronse A, Faille C, Guerardel Y. Glycosylation of BclA Glycoprotein from Bacillus cereus and Bacillus anthracis Exosporium Is Domain-specific. J Biol Chem 2016; 291:9666-77. [PMID: 26921321 DOI: 10.1074/jbc.m116.718171] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Indexed: 11/06/2022] Open
Abstract
The spores of the Bacillus cereus group (B. cereus, Bacillus anthracis, and Bacillus thuringiensis) are surrounded by a paracrystalline flexible yet resistant layer called exosporium that plays a major role in spore adhesion and virulence. The major constituent of its hairlike surface, the trimerized glycoprotein BclA, is attached to the basal layer through an N-terminal domain. It is then followed by a repetitive collagen-like neck bearing a globular head (C-terminal domain) that promotes glycoprotein trimerization. The collagen-like region of B. anthracis is known to be densely substituted by unusual O-glycans that may be used for developing species-specific diagnostics of B. anthracis spores and thus targeted therapeutic interventions. In the present study, we have explored the species and domain specificity of BclA glycosylation within the B. cereus group. First, we have established that the collagen-like regions of both B. anthracis and B. cereus are similarly substituted by short O-glycans that bear the species-specific deoxyhexose residues anthrose and the newly observed cereose, respectively. Second we have discovered that the C-terminal globular domains of BclA from both species are substituted by polysaccharide-like O-linked glycans whose structures are also species-specific. The presence of large carbohydrate polymers covering the surface of Bacillus spores may have a profound impact on the way that spores regulate their interactions with biotic and abiotic surfaces and represents potential new diagnostic targets.
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Affiliation(s)
- Emmanuel Maes
- From the Université de Lille, CNRS, UMR 8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, F-59000 Lille, France and
| | - Frederic Krzewinski
- From the Université de Lille, CNRS, UMR 8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, F-59000 Lille, France and
| | - Estelle Garenaux
- From the Université de Lille, CNRS, UMR 8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, F-59000 Lille, France and
| | | | - Bernadette Coddeville
- From the Université de Lille, CNRS, UMR 8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, F-59000 Lille, France and
| | - Xavier Trivelli
- From the Université de Lille, CNRS, UMR 8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, F-59000 Lille, France and
| | | | | | - Yann Guerardel
- From the Université de Lille, CNRS, UMR 8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, F-59000 Lille, France and
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11
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Silbereisen A, Tamborrini M, Wittwer M, Schürch N, Pluschke G. Development of a bead-based Luminex assay using lipopolysaccharide specific monoclonal antibodies to detect biological threats from Brucella species. BMC Microbiol 2015; 15:198. [PMID: 26438077 PMCID: PMC4595103 DOI: 10.1186/s12866-015-0534-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 09/25/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Brucella, a Gram-negative bacterium, is classified as a potential bioterrorism agent mainly due to the low dose needed to cause infection and the ability to transmit the bacteria via aerosols. Goats/sheep, cattle, pigs, dogs, sheep and rodents are infected by B. melitensis, B. abortus, B. suis, B. canis, B. ovis and B. neotomae, respectively, the six classical Brucella species. Most human cases are caused by B. melitensis and B. abortus. Our aim was to specifically detect Brucellae with 'smooth' lipopolysaccharide (LPS) using a highly sensitive monoclonal antibody (mAb) based immunological assay. METHODS To complement molecular detection systems for potential bioterror agents, as required by international biodefense regulations, sets of mAbs were generated by B cell hybridoma technology and used to develop immunological assays. The combination of mAbs most suitable for an antigen capture assay format was identified and an immunoassay using the Luminex xMAP technology was developed. RESULTS MAbs specific for the LPS O-antigen of Brucella spp. were generated by immunising mice with inactivated B. melitensis or B. abortus cells. Most mAbs recognised both B. melitensis and B. abortus and antigen binding was not impeded by inactivation of the bacterial cells by γ irradiation, formalin or heat treatment, a step required to analyse the samples immunologically under biosafety level two conditions. The Luminex assay recognised all tested Brucella species with 'smooth' LPS with detection limits of 2×10(2) to 8×10(4) cells per mL, depending on the species tested. Milk samples spiked with Brucella spp. cells were identified successfully using the Luminex assay. In addition, the bead-based immunoassay was integrated into a multiplex format, allowing for simultaneous, rapid and specific detection of Brucella spp., Bacillus anthracis, Francisella tularensis and Yersinia pestis within a single sample. CONCLUSION Overall, the robust Luminex assay should allow detection of Brucella spp. in both natural outbreak and bio-threat situations.
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Affiliation(s)
- Angelika Silbereisen
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
| | - Marco Tamborrini
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
| | - Matthias Wittwer
- Federal Office for Civil Protection, Spiez Laboratory, Spiez, Switzerland.
| | - Nadia Schürch
- Federal Office for Civil Protection, Spiez Laboratory, Spiez, Switzerland.
| | - Gerd Pluschke
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
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Aljahdali AZ, Shi P, Zhong Y, O'Doherty GA. De novo asymmetric synthesis of the pyranoses: from monosaccharides to oligosaccharides. Adv Carbohydr Chem Biochem 2014; 69:55-123. [PMID: 24274368 DOI: 10.1016/b978-0-12-408093-5.00004-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The various methods for the de novo asymmetric synthesis of the pyranose sugars are surveyed. The presentation begins with the work of Masamune and Sharpless with the use of the Sharpless asymmetric epoxidation for the synthesis of all eight l-hexoses. The development of other asymmetric reactions and their application for the synthesis of specific hexopyranoses are further discussed. The broad application of the Achmatowicz rearrangement with asymmetric catalysis, for the synthesis of various pyranones and imino sugars, is also presented. Finally, the use of a diastereoselective palladium-catalyzed glycosylation with the Achmatowicz approach for the synthesis of oligosaccharides and applications to medicinal chemistry are discussed.
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Affiliation(s)
- Alhanouf Z Aljahdali
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, Massachusetts, USA
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Adamo R. Glycan surface antigens fromBacillus anthracisas vaccine targets: current status and future perspectives. Expert Rev Vaccines 2014; 13:895-907. [DOI: 10.1586/14760584.2014.924404] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Wang HYL, Guo H, O'Doherty GA. De novo asymmetric synthesis of oligo-rhamno di- and tri-saccharides related to the anthrax tetrasaccharide. Tetrahedron 2013; 69:3432-3436. [PMID: 23794755 DOI: 10.1016/j.tet.2013.02.073] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
An asymmetric synthesis of the di- and trisaccharide portion of the naturally occurring anthrax tetrasaccharide from acetylfuran has been developed. The construction of the di- and trisaccharide subunits is based upon our previously disclosed route to anthrax tetrasaccharide. The approach uses iterative diastereoselective palladium-catalyzed glycosylations, Luche reductions, diastereoselective dihydroxylations, and regioselective protections for the assembly of the rhamno- di- and tri-saccharide. The route was also modified for the preparation of the mixed D-/L-disaccharide analogue.
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Affiliation(s)
- Hua-Yu Leo Wang
- College of Nuclear Technology, Chemistry and Biology, Hubei University of Science and Technology, Xianning, Hubei 437100, China ; Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, Boston, MA 02115, USA
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Dénès F, Schiesser CH, Renaud P. Thiols, thioethers, and related compounds as sources of C-centred radicals. Chem Soc Rev 2013; 42:7900-42. [DOI: 10.1039/c3cs60143a] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Milhomme O, Köhler SM, Ropartz D, Lesur D, Pilard S, Djedaïni-Pilard F, Beyer W, Grandjean C. Synthesis and immunochemical evaluation of a non-methylated disaccharide analogue of the anthrax tetrasaccharide. Org Biomol Chem 2012; 10:8524-32. [PMID: 23010801 DOI: 10.1039/c2ob26131f] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Anthrax tetrasaccharide is an oligosaccharide expressed at the outermost surface of the Bacillus anthracis spores, featuring three rhamnoses and a rare sugar called anthrose. This motif has now been identified as a plausible component of future human vaccines against anthrax. We report herein the synthesis of a 2-O-demethylated-β-D-anthropyranosyl-(1→3)-α-L-rhamnopyranose disaccharide analogue of this tetrasaccharide from a cyclic sulfate intermediate. This disaccharide conjugated to BSA induces an anti-native tetrasaccharide IgG antibody response when administered in BALB/c mice. Moreover, induced sera bound to native B. anthracis endospores. These results suggest that the disaccharide analogue, easily amenable for a synthetic scale-up, could be used in a glycoconjugate antigen formulation.
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Affiliation(s)
- Ophélie Milhomme
- Laboratoire des Glucides, FRE CNRS 3517, Institut de Chimie de Picardie, Université de Picardie Jules Verne, 33 rue Saint Leu, 80039 Amiens Cedex, France
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Milhomme O, Dhénin SG, Djedaïni-Pilard F, Moreau V, Grandjean C. Synthetic studies toward the anthrax tetrasaccharide: alternative synthesis of this antigen. Carbohydr Res 2012; 356:115-31. [DOI: 10.1016/j.carres.2012.01.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Revised: 01/15/2012] [Accepted: 01/17/2012] [Indexed: 10/14/2022]
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Development of aptamer beacons for rapid presumptive detection of Bacillus spores. J Fluoresc 2012; 22:915-24. [PMID: 22218972 DOI: 10.1007/s10895-011-1030-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Accepted: 12/19/2011] [Indexed: 10/14/2022]
Abstract
A library of 92 DNA aptamer sequences was developed against Bacillus anthracis (nonpathogenic Sterne strain) spores and anthrose sugar immobilized on magnetic beads. The selected DNA sequences were studied for similarities and potential binding pockets between the B. anthracis spore and anthrose aptamers. Several recurring loop structures were identified and tested for their potential to act as aptamer beacons when labeled with TYE 665 dye on their 5' ends and Iowa Black quencher on their 3' ends. Of these candidate sequences, two beacons designated BAS-6F and BAS-6R emerged which gave strong fluorescence responses at high spore concentrations (greater than 30,000 spores/ml). These aptamer beacons also detect B. cereus and B. thuringiensis spores with greater fluorescence intensity, but do not strongly detect vegetative cells from an array of other bacterial species. BAS-6F and 6R are also not capable of detecting pure anthrose, thereby probably ruling that epitope out as a spore surface target for these particular beacons. While not extremely sensitive, the BAS-6F and 6R aptamer beacons are potentially valuable for rapid presumptive detection of anthrax or Bacillus spores in suspect powders or bioterrorist activity where spore concentrations are anticipated to be high. The sequence similarities of these beacons to other published Bacillus spore aptamers are also discussed.
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Morelli L, Poletti L, Lay L. Carbohydrates and Immunology: Synthetic Oligosaccharide Antigens for Vaccine Formulation. European J Org Chem 2011. [DOI: 10.1002/ejoc.201100296] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Laura Morelli
- Dipartimento di Chimica Organica e Industriale, CISI and ISTM‐CNR, Università degli Studi di Milano, Via Venezian 21, 20133 Milano, Italy
| | - Laura Poletti
- Dipartimento di Chimica Organica e Industriale, CISI and ISTM‐CNR, Università degli Studi di Milano, Via Venezian 21, 20133 Milano, Italy
| | - Luigi Lay
- Dipartimento di Chimica Organica e Industriale, CISI and ISTM‐CNR, Università degli Studi di Milano, Via Venezian 21, 20133 Milano, Italy
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Milhomme O, John C, Djedaïni-Pilard F, Grandjean C. Access to antigens related to anthrose using pivotal cyclic sulfite/sulfate intermediates. J Org Chem 2011; 76:5985-98. [PMID: 21678952 DOI: 10.1021/jo200340q] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Anthrose is the upstream terminal unit of the tetrasaccharide side chain from a major glycoprotein of Bacillus anthracis exosporium and is part of important antigenic determinants. A novel entry to anthrose-containing antigens and precursors is described. The synthetic route, starting from D(+)-fucose, makes use of intermediates featuring a cyclic sulfite or sulfate function which serves successively as a protecting and a leaving group.
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Affiliation(s)
- Ophélie Milhomme
- Laboratoire des Glucides, UMR CNRS 6219, Institut de Chimie de Picardie, Université de Picardie Jules Verne, 33 rue Saint Leu, 80039 Amiens Cedex, France
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21
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Concise synthesis of Bacillus anthracis exosporium tetrasaccharide via two-stage activation of allyl glycosyl donor strategy. Tetrahedron Lett 2011. [DOI: 10.1016/j.tetlet.2011.05.089] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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22
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Identification of an African Bacillus anthracis lineage that lacks expression of the spore surface-associated anthrose-containing oligosaccharide. J Bacteriol 2011; 193:3506-11. [PMID: 21571994 DOI: 10.1128/jb.00078-11] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The surfaces of Bacillus anthracis endospores expose a pentasaccharide containing the monosaccharide anthrose, which has been considered for use as a vaccine or target for specific detection of the spores. In this study B. anthracis strains isolated from cattle carcasses in African countries where anthrax is endemic were tested for their cross-reactivity with monoclonal antibodies (MAbs) specific for anthrose-containing oligosaccharides. Unexpectedly, none of the isolates collected in Chad, Cameroon, and Mali were recognized by the MAbs. Sequencing of the four-gene operon encoding anthrose biosynthetic enzymes revealed the presence of premature stop codons in the aminotransferase and glycosyltransferase genes in all isolates from Chad, Cameroon, and Mali. Both immunological and genetic findings suggest that the West African isolates are unable to produce anthrose. The anthrose-deficient strains from West Africa belong to a particular genetic lineage. Immunization of cattle in Chad with a locally produced vaccine based on anthrose-positive spores of the B. anthracis strain Sterne elicited an anti-carbohydrate IgG response specific for a synthetic anthrose-containing tetrasaccharide as demonstrated by glycan microarray analysis. Competition immunoblots with synthetic pentasaccharide derivatives suggested an immunodominant role of the anthrose-containing carbohydrate in cattle. In West Africa anthrax is highly endemic. Massive vaccination of livestock in this area has taken place over long periods of time using spores of the anthrose-positive vaccine strain Sterne. The spread of anthrose-deficient strains in this region may represent an escape strategy of B. anthracis.
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23
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Oberli MA, Tamborrini M, Tsai YH, Werz DB, Horlacher T, Adibekian A, Gauss D, Möller HM, Pluschke G, Seeberger PH. Molecular analysis of carbohydrate-antibody interactions: case study using a Bacillus anthracis tetrasaccharide. J Am Chem Soc 2010; 132:10239-41. [PMID: 20614885 DOI: 10.1021/ja104027w] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The process for selecting potent and effective carbohydrate antigens is not well-established. A combination of synthetic glycan microarray screening, surface plasmon resonance analysis, and saturation transfer difference NMR spectroscopy was used to dissect the antibody-binding surface of a carbohydrate antigen, revealing crucial binding elements with atomic-level detail. This analysis takes the first step toward uncovering the rules for structure-based design of carbohydrate antigens.
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Affiliation(s)
- Matthias A Oberli
- Department of Biomolecular Systems, Max-Planck Institute for Colloids and Interfaces, 14476 Potsdam, Germany
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24
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Combination of solid phase and solution phase synthesis of oligosaccharides using sonication. Tetrahedron Lett 2010. [DOI: 10.1016/j.tetlet.2010.06.027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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25
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Anthrax spore detection by a luminex assay based on monoclonal antibodies that recognize anthrose-containing oligosaccharides. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2010; 17:1446-51. [PMID: 20660139 DOI: 10.1128/cvi.00205-10] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The similarity of endospore surface antigens between bacteria of the Bacillus cereus group complicates the development of selective antibody-based anthrax detection systems. The surface of B. anthracis endospores exposes a tetrasaccharide containing the monosaccharide anthrose. Anti-tetrasaccharide monoclonal antibodies (MAbs) and anti-anthrose-rhamnose disaccharide MAbs were produced and tested for their fine specificities in a direct spore enzyme-linked immunosorbent assay (ELISA) with inactivated spores of a broad spectrum of B. anthracis strains and related species of the Bacillus genus. Although the two sets of MAbs had different fine specificities, all of them recognized the tested B. anthracis strains and showed only a limited cross-reactivity with two B. cereus strains. The MAbs were further tested for their ability to be implemented in a highly sensitive and specific bead-based Luminex assay. This assay detected spores from different B. anthracis strains and two cross-reactive B. cereus strains, correlating with the results obtained in direct spore ELISA. The Luminex assay (detection limit 10(3) to 10(4) spores per ml) was much more sensitive than the corresponding sandwich ELISA. Although not strictly specific for B. anthracis spores, the developed Luminex assay represents a useful first-line screening tool for the detection of B. anthracis spores.
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26
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Beaver MG, Woerpel KA. Erosion of stereochemical control with increasing nucleophilicity: O-glycosylation at the diffusion limit. J Org Chem 2010; 75:1107-18. [PMID: 20108907 DOI: 10.1021/jo902222a] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Nucleophilic substitution reactions of 2-deoxyglycosyl donors indicated that the reactivity of the oxygen nucleophile has a significant impact on stereoselectivity. Employing ethanol as the nucleophile resulted in a 1:1 (alpha:beta) ratio of diastereomers under S(N)1-like reaction conditions. Stereoselective formation of the 2-deoxy-alpha-O-glycoside was only observed when weaker nucleophiles, such as trifluoroethanol, were employed. The lack of stereoselectivity observed in reactions of common oxygen nucleophiles can be attributed to reaction rates of the stereochemistry-determining step that approach the diffusion limit. In this scenario, both faces of the prochiral oxocarbenium ion are subject to nucleophilic addition to afford a statistical mixture of diastereomeric products. Control experiments confirmed that all nucleophilic substitution reactions were performed under kinetic control.
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Affiliation(s)
- Matthew G Beaver
- Department of Chemistry, University of California, Irvine, California 92697-2025, USA
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27
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Dhénin SGY, Moreau V, Nevers MC, Créminon C, Djedaïni-Pilard F. Sensitive and specific enzyme immunoassays for antigenic trisaccharide from Bacillus anthracis spores. Org Biomol Chem 2009; 7:5184-99. [PMID: 20024115 DOI: 10.1039/b914534f] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A straightforward synthesis of an anthrose-containing trisaccharide derived from Bacillus anthracis was achieved. Antibodies raised against this hapten provide a highly sensitive enzyme immunoassay with a detection limit of 8.5 pmol mL(-1). By investigating the specificity of the antibodies obtained using different mono-, di- and trisaccharide synthetic analogues, we demonstrated that the epitope was mainly made up of the methyl group at C-5, the butamido group at C-4 and the hydroxyl at C-3 of the anthrose unit, the other parts of the trisaccharide appearing little involved in the recognition.
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Affiliation(s)
- Sandrine G Y Dhénin
- Laboratoire des Glucides, UMR-CNRS 6219, Institut de Chimie de Picardie, Université de Picardie Jules Verne, 33 rue St Leu, F-80039, Amiens, France
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29
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Development of antibodies against anthrose tetrasaccharide for specific detection of Bacillus anthracis spores. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2009; 16:1728-37. [PMID: 19793896 DOI: 10.1128/cvi.00235-09] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Methods for the immunological detection of Bacillus anthracis in various environmental samples and the discrimination of B. anthracis from other members of the B. cereus group are not yet well established. To generate specific discriminating antibodies, we immunized rabbits, mice, and chickens with inactivated B. anthracis spores and, additionally, immunized rabbits and mice with the tetrasaccharide beta-Ant-(1-->3)-alpha-L-Rhap-(1-->3)-alpha-L-Rhap-(1-->2)-L-Rhap. It is a constituent of the exosporium glycoprotein BclA and contains the newly discovered sugar anthrose 2-O-methyl-4-(3-hydroxy-3-methylbutamido)-4,6-dideoxy-beta-D-glucose. The BclA protein is a major component of the exosporium of B. anthracis spores and is decorated by the tetrasaccharide indicated above. The anthrose-containing tetrasaccharide chain seems to be highly specific for B. anthracis, which makes it a key biomarker for the detection of these spores. The different immunizations led to anthrose-reactive polyclonal and monoclonal antibodies which were analyzed by various methods to characterize their ability to discriminate between B. anthracis and other Bacillus spp. Multiple applications, such as enzyme-linked immunosorbent assay, indirect immunofluorescence assay, and electron microscopy, revealed the specificities of the polyclonal and monoclonal antibodies generated for B. anthracis spore detection. All polyclonal antibodies were able to correctly identify the B. anthracis strains tested and showed only minimal cross-reactivities with other Bacillus strains. Moreover, the antibodies generated proved functional in a new capture assay for B. anthracis spores and could therefore be useful for the detection of spores in complex samples.
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30
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Affiliation(s)
- Feng Cai
- Department of Chemistry, Wayne State University, Detroit, MI 48202, USA
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31
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Tamborrini M, Oberli M, Werz D, Schürch N, Frey J, Seeberger P, Pluschke G. Immuno-detection of anthrose containing tetrasaccharide in the exosporium ofBacillus anthracisandBacillus cereusstrains. J Appl Microbiol 2009; 106:1618-28. [DOI: 10.1111/j.1365-2672.2008.04129.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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34
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Son SH, Tano C, Furuike T, Sakairi N. Pre-activation of fully acetylated dodecyl thioglycosides with BSP–Tf2O led to efficient glycosylation at low temperature. Carbohydr Res 2009; 344:285-90. [DOI: 10.1016/j.carres.2008.11.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2008] [Revised: 11/11/2008] [Accepted: 11/12/2008] [Indexed: 11/27/2022]
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35
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Vasan M, Rauvolfova J, Wolfert MA, Leoff C, Kannenberg EL, Quinn CP, Carlson RW, Boons GJ. Chemical synthesis and immunological properties of oligosaccharides derived from the vegetative cell wall of Bacillus anthracis. Chembiochem 2008; 9:1716-20. [PMID: 18563773 PMCID: PMC2832322 DOI: 10.1002/cbic.200800210] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Indexed: 11/08/2022]
Abstract
Bacillus anthracis vaccine candidate : Sera of rabbits exposed to live and irradiated-killed spores of B. anthracis Sterne 34F2 or immunized with B. anthracis polysaccharide conjugated to KLH elicited antibodies that recognize isolated polysaccharide and two synthetic trisaccharides providing a proof-of-concept step in the development of vegetative and spore-specific reagents for detection and targeting of non-protein structures of B. anthracis .
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Affiliation(s)
- Mahalakshmi Vasan
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602 (USA)
| | - Jana Rauvolfova
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602 (USA)
| | - Margreet A. Wolfert
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602 (USA)
| | - Christine Leoff
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602 (USA)
| | - Elmar L. Kannenberg
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602 (USA)
| | - Conrad P. Quinn
- Centers for Disease Control and Prevention§, Microbial Pathogenesis and Immune Response Laboratory, Meningitis and Vaccine Preventable Diseases Branch, NCIRD, DBD, 1600 Clifton Road, MS D-11, Atlanta, GA 30333 (USA)
| | - Russell W. Carlson
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602 (USA)
| | - Geert-Jan Boons
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602 (USA)
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36
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Guo H, O’Doherty GA. De Novo Asymmetric Synthesis of Anthrax Tetrasaccharide and Related Tetrasaccharide. J Org Chem 2008; 73:5211-20. [PMID: 18563936 DOI: 10.1021/jo800691v] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Haibing Guo
- Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506
| | - George A. O’Doherty
- Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506
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37
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Saccharides cross-reactive with Bacillus anthracis spore glycoprotein as an anthrax vaccine component. Proc Natl Acad Sci U S A 2008; 105:8709-12. [PMID: 18562275 DOI: 10.1073/pnas.0803897105] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Bacillus anthracis is a spore-forming bacterium that causes anthrax in humans and in other mammals. The glycoprotein BclA (Bacillus collagen-like protein of anthracis) is a major constituent of the exosporium, the outermost surface of B. anthracis spores. The glycosyl part of BclA is an oligosaccharide composed of 2-O-methyl-4-(3-hydroxy-3-methylbutanamido)-4,6-dideoxy-d-glucose, referred to as anthrose, and three rhamnose residues. A structure similar to anthrose, 4-(3-hydroxy-3-methylbutanamido)-4,6-dideoxy-d-glucose is found in the side chain of the capsular polysaccharide (CPS) of Shewanella spp. MR-4. Under certain growth conditions the bacteria produce a variant CPS lacking one methyl group on the hydroxybutyrate, 4-(3-hydroxybutanamido)-4,6-dideoxy-d-glucose. Contrary to anthrose, neither of the Shewanella CPSs is 2-O methylated. Here, we report that both Shewanella CPS variants react with anti-B. anthracis spore sera. We also found that these antisera reacted with flagellae of Pseudomonas syringae, reported to be glycosylated with a similar terminal saccharide, 4-(3-hydroxybutanamido)-4,6-dideoxy-2-O-methyl-d-glucose. Sera produced by immunization with Shewanella or P. syringae cells bound to B. anthracis spores but not to Bacillus cereus spores in a fluorescent microscopy assay. These experiments show that methylation of the anthrose at the O-2 of the sugar ring and at the C-3 of 3-hydroxybutyrate are not essential for induction of cross-reactive antibodies. We report the preparation, characterization, and antibody responses to protein conjugates of the two variants of Shewanella CPS. Both conjugates induced antibodies that bound to both Shewanella CPS variants by ELISA and to B. anthracis spores, as detected by fluorescent microscopy. We propose the use of Shewanella CPS conjugates as a component of an anthrax vaccine.
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38
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Hou S, Kováč P. A Convenient Synthesis of Furanose-FreeD-Fucose Per-O-Acetates and a Precursor for Anthrose. European J Org Chem 2008. [DOI: 10.1002/ejoc.200701173] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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39
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Abstract
The exosporium of Bacillus anthracis spores consists of a basal layer and an external hair-like nap. The nap is composed primarily of the glycoprotein BclA, which contains a collagen-like region with multiple copies of a pentasaccharide side chain. This oligosaccharide possesses an unusual terminal sugar called anthrose, followed by three rhamnose residues and a protein-bound N-acetylgalactosamine. Based on the structure of anthrose, we proposed an enzymatic pathway for its biosynthesis. Examination of the B. anthracis genome revealed six contiguous genes that could encode the predicted anthrose biosynthetic enzymes. These genes are transcribed in the same direction and appear to form two operons. We introduced mutations into the B. anthracis chromosome that either delete the promoter of the putative upstream, four-gene operon or delete selected genes in both putative operons. Spores produced by strains carrying mutations in the upstream operon completely lacked or contained much less anthrose, indicating that this operon is required for anthrose biosynthesis. In contrast, inactivation of the downstream, two-gene operon did not alter anthrose content. Additional experiments confirmed the organization of the anthrose operon and indicated that it is transcribed from a sigma(E)-specific promoter. Finally, we demonstrated that anthrose biosynthesis is not restricted to B. anthracis as previously suggested.
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Synthesis of an anthrose derivative and production of polyclonal antibodies for the detection of anthrax spores. Carbohydr Res 2007; 343:2101-10. [PMID: 18155682 DOI: 10.1016/j.carres.2007.11.030] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2007] [Revised: 11/29/2007] [Accepted: 11/30/2007] [Indexed: 11/23/2022]
Abstract
A straightforward synthesis of a derivative of anthrose, the non-reducing terminal fragment of the antigenic tetrasaccharide from Bacillus anthracis, was achieved starting from d-galactose. This hapten is able to induce a highly specific and sensitive immune response in rabbit when attached to a carrier protein.
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