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Homayonia S, Ling CC. Epoxide-Mediated Trans-Thioglycosylation and Application to the Synthesis of Oligosaccharides Related to the Capsular Polysaccharides of C. jejuni HS:4. Chemistry 2024; 30:e202303753. [PMID: 38215247 DOI: 10.1002/chem.202303753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 01/10/2024] [Accepted: 01/10/2024] [Indexed: 01/14/2024]
Abstract
The enzyme-resistant thioglycosides are highly valuable immunogens because of their enhanced metabolic stability. We report the first synthesis of a family of thiooligosaccharides related to the capsular polysaccharides (CPS) of Campylobacter jejuni HS:4 for potential use in conjugate vaccines. The native CPS structures of the pathogen consist of a challenging repeating disaccharide formed with β(1→4)-linked 6-deoxy-β-D-ido-heptopyranoside and N-acetyl-D-glucosamine; the rare 6-deoxy-ido-heptopyranosyl backbone and β-anomeric configuration of the former monosaccharide makes the synthesis of this family of antigens very challenging. So far, no synthesis of the thioanalogs of the CPS antigens have been reported. The unprecedented synthesis presented in this work is built on an elegant approach by using β-glycosylthiolate as a glycosyl donor to open the 2,3-epoxide functionality of pre-designed 6-deoxy-β-D-talo-heptopyranosides. Our results illustrated that this key trans-thioglycosylation can be designed in a modular and regio and stereo-selective manner. Built on the success of this novel approach, we succeeded the synthesis of a family of thiooligosaccharides including a thiohexasaccharide which is considered to be the desired antigen length and complexity for immunizations. We also report the first direct conversion of base-stable but acid-labile 2-trimethylsilylethyl glycosides to glycosyl-1-thioacetates in a one-pot manner.
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Affiliation(s)
- Saba Homayonia
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, T2N 1N4, Canada
| | - Chang-Chun Ling
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, T2N 1N4, Canada
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2
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Feng G, Wang S, Lv J, Luo T, Wu Y, Dong H. Improved Synthesis of 1‐Glycosyl Thioacetates and Its Application in the Synthesis of Thioglucoside Gliflozin Analogues. European J Org Chem 2021. [DOI: 10.1002/ejoc.202100357] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Guang‐Jing Feng
- Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of Education, School of Chemistry & Chemical Engineering Huazhong University of Science & Technology Luoyu Road 1037 Wuhan 430074 PR China
| | - Shuang‐Shuang Wang
- Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of Education, School of Chemistry & Chemical Engineering Huazhong University of Science & Technology Luoyu Road 1037 Wuhan 430074 PR China
| | - Jian Lv
- Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of Education, School of Chemistry & Chemical Engineering Huazhong University of Science & Technology Luoyu Road 1037 Wuhan 430074 PR China
| | - Tao Luo
- Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of Education, School of Chemistry & Chemical Engineering Huazhong University of Science & Technology Luoyu Road 1037 Wuhan 430074 PR China
| | - Yuzhou Wu
- Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of Education, School of Chemistry & Chemical Engineering Huazhong University of Science & Technology Luoyu Road 1037 Wuhan 430074 PR China
| | - Hai Dong
- Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of Education, School of Chemistry & Chemical Engineering Huazhong University of Science & Technology Luoyu Road 1037 Wuhan 430074 PR China
- Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica Huazhong University of Science & Technology Luoyu Road 1037 Wuhan 430074 PR China
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3
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Hirai G, Kato M, Koshino H, Nishizawa E, Oonuma K, Ota E, Watanabe T, Hashizume D, Tamura Y, Okada M, Miyagi T, Sodeoka M. Ganglioside GM3 Analogues Containing Monofluoromethylene-Linked Sialoside: Synthesis, Stereochemical Effects, Conformational Behavior, and Biological Activities. JACS Au 2021; 1:137-146. [PMID: 34467279 PMCID: PMC8395706 DOI: 10.1021/jacsau.0c00058] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Indexed: 05/12/2023]
Abstract
Glycoconjugates are an important class of biomolecules that regulate numerous biological events in cells. However, these complex, medium-size molecules are metabolically unstable, which hampers detailed investigations of their functions as well as their potential application as pharmaceuticals. Here we report sialidase-resistant analogues of ganglioside GM3 containing a monofluoromethylene linkage instead of the native O-sialoside linkage. Stereoselective synthesis of CHF-linked disaccharides and kinetically controlled Au(I)-catalyzed glycosylation efficiently furnished both stereoisomers of CHF-linked as well as CF 2 - and CH 2 -linked GM3 analogues. Like native GM3, the C-linked GM3 analogues inhibited the autophosphorylation of epidermal growth factor (EGF) receptor induced by EGF in vitro. Assay of the proliferation-enhancing activity toward Had-1 cells together with NMR-based conformational analysis showed that the (S)-CHF-linked GM3 analogue with exo-gauche conformation is the most potent of the synthesized compounds. Our findings suggest that exo-anomeric conformation is important for the biological functions of GM3.
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Affiliation(s)
- Go Hirai
- Graduate
School of Pharmaceutical Sciences, Kyushu
University, 3-1-1, Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
- RIKEN
Cluster for Pioneering Resaerch, Synthetic Organic Chemistry Laboratory, 2-1, Hirosawa, Wako, Saitama 351-0198, Japan
- RIKEN
Center for Sustainable Resource Science, 2-1, Hirosawa, Wako, Saitama 351-0198, Japan
| | - Marie Kato
- RIKEN
Cluster for Pioneering Resaerch, Synthetic Organic Chemistry Laboratory, 2-1, Hirosawa, Wako, Saitama 351-0198, Japan
- Tokyo
Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Hiroyuki Koshino
- RIKEN
Center for Sustainable Resource Science, 2-1, Hirosawa, Wako, Saitama 351-0198, Japan
| | - Eri Nishizawa
- RIKEN
Cluster for Pioneering Resaerch, Synthetic Organic Chemistry Laboratory, 2-1, Hirosawa, Wako, Saitama 351-0198, Japan
- Tokyo
Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Kana Oonuma
- RIKEN
Center for Sustainable Resource Science, 2-1, Hirosawa, Wako, Saitama 351-0198, Japan
| | - Eisuke Ota
- RIKEN
Cluster for Pioneering Resaerch, Synthetic Organic Chemistry Laboratory, 2-1, Hirosawa, Wako, Saitama 351-0198, Japan
| | - Toru Watanabe
- RIKEN
Cluster for Pioneering Resaerch, Synthetic Organic Chemistry Laboratory, 2-1, Hirosawa, Wako, Saitama 351-0198, Japan
| | - Daisuke Hashizume
- RIKEN
Center for Emergent Matter Science, 2-1, Hirosawa, Wako, Saitama 351-0198, Japan
| | - Yuki Tamura
- RIKEN
Cluster for Pioneering Resaerch, Synthetic Organic Chemistry Laboratory, 2-1, Hirosawa, Wako, Saitama 351-0198, Japan
| | - Mitsuaki Okada
- RIKEN
Cluster for Pioneering Resaerch, Synthetic Organic Chemistry Laboratory, 2-1, Hirosawa, Wako, Saitama 351-0198, Japan
- Tokyo
Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Taeko Miyagi
- Miyagi Cancer
Center Research Institute, Natori 981-1293, Japan
| | - Mikiko Sodeoka
- RIKEN
Cluster for Pioneering Resaerch, Synthetic Organic Chemistry Laboratory, 2-1, Hirosawa, Wako, Saitama 351-0198, Japan
- RIKEN
Center for Sustainable Resource Science, 2-1, Hirosawa, Wako, Saitama 351-0198, Japan
- Tokyo
Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
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4
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Ma ST, Lee CW, Liu WM. Synthesis of 4-thiol-furanosidic uronate via hydrothiolation reaction. RSC Adv 2021; 11:18409-18416. [PMID: 35480947 PMCID: PMC9033442 DOI: 10.1039/d1ra02110a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 05/05/2021] [Indexed: 11/25/2022] Open
Abstract
Uronic acids are not only important building blocks of polysaccharides and oligosaccharides but also are widely used in the food and pharmaceutical industries. Inspired by the structure of natural products, here, we disclosed base-mediated and radical-mediated hydrothiolation reactions for the preparation of thiol-contained uronates. In comparison with base-mediated reaction, radical-mediated hydrothiolation is inefficient due to the electron-withdrawing group on the ethylene group; nevertheless, the adduct had excellent stereoselectivity at both C-4 and C-5 positions. For the alkaline approach, thiols as nucleophiles can regioselectively and stereoselectively attach to the C-4 position of Δ-4,5-unsaturated uronate with moderate to good yields. However, poor stereoselectivity at the C-5 position was observed due to retro thiol-Michael addition. After removing the protecting group of the thiol, the thiol adduct was isomerized to the furanosidic form and the 4-thiol-furanosidic uronate derivative was synthesized for the first time. Uronic acids are not only important building blocks of bioactive molecules but also are widely used in the food and pharmaceutical industries. Its derivative, 4-thiol-furanosidic uronate was successfully synthesized and firstly reported here.![]()
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Affiliation(s)
- Shih-Ting Ma
- Department of Chemistry
- Fu Jen Catholic University
- New Taipei City 24205
- Republic of China
| | - Chia-Wei Lee
- Department of Chemistry
- Fu Jen Catholic University
- New Taipei City 24205
- Republic of China
| | - Wei-Min Liu
- Department of Chemistry
- Fu Jen Catholic University
- New Taipei City 24205
- Republic of China
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Streltsov VA, Luang S, Peisley A, Varghese JN, Ketudat Cairns JR, Fort S, Hijnen M, Tvaroška I, Ardá A, Jiménez-Barbero J, Alfonso-Prieto M, Rovira C, Mendoza F, Tiessler-Sala L, Sánchez-Aparicio JE, Rodríguez-Guerra J, Lluch JM, Maréchal JD, Masgrau L, Hrmova M. Discovery of processive catalysis by an exo-hydrolase with a pocket-shaped active site. Nat Commun 2019; 10:2222. [PMID: 31110237 DOI: 10.1038/s41467-019-09691-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 03/22/2019] [Indexed: 11/08/2022] Open
Abstract
Substrates associate and products dissociate from enzyme catalytic sites rapidly, which hampers investigations of their trajectories. The high-resolution structure of the native Hordeum exo-hydrolase HvExoI isolated from seedlings reveals that non-covalently trapped glucose forms a stable enzyme-product complex. Here, we report that the alkyl β-d-glucoside and methyl 6-thio-β-gentiobioside substrate analogues perfused in crystalline HvExoI bind across the catalytic site after they displace glucose, while methyl 2-thio-β-sophoroside attaches nearby. Structural analyses and multi-scale molecular modelling of nanoscale reactant movements in HvExoI reveal that upon productive binding of incoming substrates, the glucose product modifies its binding patterns and evokes the formation of a transient lateral cavity, which serves as a conduit for glucose departure to allow for the next catalytic round. This path enables substrate-product assisted processive catalysis through multiple hydrolytic events without HvExoI losing contact with oligo- or polymeric substrates. We anticipate that such enzyme plasticity could be prevalent among exo-hydrolases. Enzyme substrates and products often diffuse too rapidly to assess the catalytic implications of these movements. Here, the authors characterise the structural basis of product and substrate diffusion for an exo-hydrolase and discover a substrate-product assisted processive catalytic mechanism.
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6
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Lacetera A, Berbís MÁ, Nurisso A, Jiménez-Barbero J, Martín-Santamaría S. Computational Chemistry Tools in Glycobiology: Modelling of Carbohydrate–Protein Interactions. Computational Tools for Chemical Biology 2017. [DOI: 10.1039/9781788010139-00145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Molecular modelling provides a major impact in the field of glycosciences, helping in the characterisation of the molecular basis of the recognition between lectins from pathogens and human glycoconjugates, and in the design of glycocompounds with anti-infectious properties. The conformational properties of oligosaccharides are complex, and therefore, the simulation of these properties is a challenging task. Indeed, the development of suitable force fields is required for the proper simulation of important problems in glycobiology, such as the interatomic interactions responsible for oligosaccharide and glycoprotein dynamics, including O-linkages in oligo- and polysaccharides, and N- and O-linkages in glycoproteins. The computational description of representative examples is discussed, herein, related to biologically active oligosaccharides and their interaction with lectins and other proteins, and the new routes open for the design of glycocompounds with promising biological activities.
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Affiliation(s)
- Alessandra Lacetera
- Center for Biological Research CIB-CSIC. Ramiro de Maeztu, 9 28040-Madrid Spain
| | - M. Álvaro Berbís
- Center for Biological Research CIB-CSIC. Ramiro de Maeztu, 9 28040-Madrid Spain
| | - Alessandra Nurisso
- School of Pharmaceutical Sciences University of Geneva, University of Lausanne, Rue Michel Servet 1 CH-1211 Geneva 4 Switzerland
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7
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Norberg O, Wu B, Thota N, Ge JT, Fauquet G, Saur AK, Aastrup T, Dong H, Yan M, Ramström O. Synthesis and binding affinity analysis of α1-2- and α1-6- O / S -linked dimannosides for the elucidation of sulfur in glycosidic bonds using quartz crystal microbalance sensors. Carbohydr Res 2017; 452:35-42. [DOI: 10.1016/j.carres.2017.09.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 09/26/2017] [Accepted: 09/30/2017] [Indexed: 01/05/2023]
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8
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Kuan TC, Wu HR, Adak AK, Li BY, Liang CF, Hung JT, Chiou SP, Yu AL, Hwu JR, Lin CC. Synthesis of an S-Linked α(2→8) GD3 Antigen and Evaluation of the Immunogenicity of Its Glycoconjugate. Chemistry 2017; 23:6876-6887. [DOI: 10.1002/chem.201700506] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Indexed: 12/19/2022]
Affiliation(s)
- Ting-Chun Kuan
- Department of Chemistry; National Tsing Hua University; Hsinchu- 300 Taiwan
| | - Hsin-Ru Wu
- Department of Chemistry; National Tsing Hua University; Hsinchu- 300 Taiwan
| | - Avijit K. Adak
- Department of Chemistry; National Tsing Hua University; Hsinchu- 300 Taiwan
| | - Ben-Yuan Li
- Department of Chemistry; National Tsing Hua University; Hsinchu- 300 Taiwan
| | - Chien-Fu Liang
- Department of Chemistry; National Chung Hsing University, Taichung; Taiwan
| | - Jung-Tung Hung
- Institute of Stem Cell and Translational Cancer Research; Chang Gung Memorial Hospital; Linkou Taiwan
| | - Shih-Pin Chiou
- Institute of Stem Cell and Translational Cancer Research; Chang Gung Memorial Hospital; Linkou Taiwan
| | - Alice L. Yu
- Institute of Stem Cell and Translational Cancer Research; Chang Gung Memorial Hospital; Linkou Taiwan
| | - Jih Ru Hwu
- Department of Chemistry; National Tsing Hua University; Hsinchu- 300 Taiwan
| | - Chun-Cheng Lin
- Department of Chemistry; National Tsing Hua University; Hsinchu- 300 Taiwan
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9
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Wu B, Ge J, Ren B, Pei Z, Dong H. Synthesis and binding affinity analysis of positional thiol analogs of mannopyranose for the elucidation of sulfur in different position. Tetrahedron 2015; 71:4023-30. [DOI: 10.1016/j.tet.2015.04.060] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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10
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Marelli UK, Frank AO, Wahl B, La Pietra V, Novellino E, Marinelli L, Herdtweck E, Groll M, Kessler H. Receptor-bound conformation of cilengitide better represented by its solution-state structure than the solid-state structure. Chemistry 2014; 20:14201-6. [PMID: 25251673 DOI: 10.1002/chem.201403839] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Indexed: 11/09/2022]
Abstract
The X-ray crystal and NMR spectroscopic structures of the peptide drug candidate Cilengitide (cyclo(RGDf(NMe)Val)) in various solvents are obtained and compared in addition to the integrin receptor bound conformation. The NMR-based solution structures exhibit conformations closely resembling the X-ray structure of Cilengitide bound to the head group of integrin αvβ3. In contrast, the structure of pure Cilengitide recrystallized from methanol reveals a different conformation controlled by the lattice forces of the crystal packing. Molecular modeling studies of the various ligand structures docked to the αvβ3 integrin revealed that utilization of the solid-state conformation of Cilengitide leads-unlike the solution-based structures-to a mismatch of the ligand-receptor interactions compared with the experimentally determined structure of the protein-ligand complex. Such discrepancies between solution and crystal conformations of ligands can be misleading during the structure-based lead optimization process and should thus be taken carefully into account in ligand orientated drug design.
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Affiliation(s)
- Udaya Kiran Marelli
- Institute for Advanced Study (IAS) and Center for Integrated Protein Science (CIPSM), Department Chemie, Technische Universität München, Lichtenbergstr. 4, 85747 Garching (Germany)
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11
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Rojas V, Carreras J, Corzana F, Avenoza A, Busto JH, Peregrina JM. Synthesis and conformational analysis of neoglycoconjugates derived from O- and S-glucose. Carbohydr Res 2013; 373:1-8. [PMID: 23545325 DOI: 10.1016/j.carres.2013.02.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 02/27/2013] [Accepted: 02/28/2013] [Indexed: 10/27/2022]
Abstract
Using olefin metathesis as a key step, four neoglycoconjugates incorporating α-O-glucose, α-S-glucose or β-S-glucose as a carbohydrate unit and L-serine or L-cysteine as an amino acid moiety have been synthesized. The four-atom carbon spacer allows the carbohydrate to explore a wide-ranging conformational space, which may have important implications for the molecular recognition of these molecules.
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Affiliation(s)
- Víctor Rojas
- Departamento de Química, Universidad de La Rioja, Centro de Investigación en Síntesis Química, Logroño, La Rioja, Spain
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12
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Freire-de-Lima L, Oliveira IA, Neves JL, Penha LL, Alisson-Silva F, Dias WB, Todeschini AR. Sialic acid: a sweet swing between mammalian host and Trypanosoma cruzi. Front Immunol 2012; 3:356. [PMID: 23230438 PMCID: PMC3515882 DOI: 10.3389/fimmu.2012.00356] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2012] [Accepted: 11/08/2012] [Indexed: 02/02/2023] Open
Abstract
Commonly found at the outermost ends of complex carbohydrates in extracellular medium or on outer cell membranes, sialic acids play important roles in a myriad of biological processes. Mammals synthesize sialic acid through a complex pathway, but Trypanosoma cruzi, the agent of Chagas’ disease, evolved to obtain sialic acid from its host through a trans-sialidase (TcTS) reaction. Studies of the parasite cell surface architecture and biochemistry indicate that a unique system comprising sialoglycoproteins and sialyl-binding proteins assists the parasite in several functions including parasite survival, infectivity, and host–cell recognition. Additionally, TcTS activity is capable of extensively remodeling host cell glycomolecules, playing a role as virulence factor. This review presents the state of the art of parasite sialobiology, highlighting how the interplay between host and parasite sialic acid helps the pathogen to evade host defense mechanisms and ensure lifetime host parasitism.
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Affiliation(s)
- Leonardo Freire-de-Lima
- Laboratório de Glicobiologia Estrutural e Funcional, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro Brazil
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Abstract
Cancer cells can often be distinguished from healthy cells by the expression of unique carbohydrate sequences decorating the cell surface as a result of aberrant glycosyltransferase activity occurring within the cell; these unusual carbohydrates can be used as valuable immunological targets in modern vaccine designs to raise carbohydrate-specific antibodies. Many tumor antigens (e.g., GM2, Ley, globo H, sialyl Tn and TF) have been identified to date in a variety of cancers. Unfortunately, carbohydrates alone evoke poor immunogenicity, owing to their lack of ability in inducing T-cell-dependent immune responses. In order to enhance their immunogenicity and promote long-lasting immune responses, carbohydrates are often chemically modified to link to an immunogenic protein or peptide fragment for eliciting T-cell-dependent responses. This review will present a summary of efforts and advancements made to date on creating carbohydrate-based anticancer vaccines, and will include novel approaches to overcoming the poor immunogenicity of carbohydrate-based vaccines.
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14
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15
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Fettke A, Kramer M, Kleinpeter E. Lectin-bound conformations and non-covalent interactions of glycomimetic analogs of thiochitobiose. Tetrahedron 2010. [DOI: 10.1016/j.tet.2010.04.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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16
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Jiménez-Barbero J, L. Asensio J, Cuevas G, Canales A, Fernández-Alonso MC, Javier Cañada F. Conformational insights on the molecular recognition processes of carbohydrate molecules by proteins and enzymes: A 3D view by using NMR. BIOCATAL BIOTRANSFOR 2009. [DOI: 10.1080/10242420600598103] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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17
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Affiliation(s)
- Michele Fiore
- Dipartmento di Chimica, Laboratorio di Chimica Organica, Università di Ferrara, Via L. Borsari 46, 44100 Ferrara, Italy
| | - Alberto Marra
- Dipartmento di Chimica, Laboratorio di Chimica Organica, Università di Ferrara, Via L. Borsari 46, 44100 Ferrara, Italy
| | - Alessandro Dondoni
- Dipartmento di Chimica, Laboratorio di Chimica Organica, Università di Ferrara, Via L. Borsari 46, 44100 Ferrara, Italy
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18
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Fiore M, Chambery A, Marra A, Dondoni A. Single and dual glycoside clustering around calix[4]arene scaffolds via click thiol–ene coupling and azide–alkyne cycloaddition. Org Biomol Chem 2009; 7:3910-3. [DOI: 10.1039/b912686d] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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20
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Isorna P, Polaina J, Latorre-García L, Cañada FJ, González B, Sanz-Aparicio J. Crystal structures of Paenibacillus polymyxa beta-glucosidase B complexes reveal the molecular basis of substrate specificity and give new insights into the catalytic machinery of family I glycosidases. J Mol Biol 2007; 371:1204-18. [PMID: 17585934 DOI: 10.1016/j.jmb.2007.05.082] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2007] [Revised: 05/22/2007] [Accepted: 05/25/2007] [Indexed: 11/19/2022]
Abstract
Bacteria species involved in degradation of cellulosic substrates produce a variety of enzymes for processing related compounds along the hydrolytic pathway. Paenibacillus polymyxa encodes two homologous beta-glucosidases, BglA and BglB, presenting different quaternary structures and substrate specificities. We previously reported the 3D-structure of BglA, which is highly specific against cellobiose. Here, we present structural analysis of BglB, a monomeric enzyme that acts as an exo-beta-glucosidase hydrolyzing cellobiose and cellodextrins of higher degree of polymerization. The crystal structure of BglB shows that several polar residues narrow the active site pocket and contour additional subsites. The structure of the BglB-cellotetraose complex confirms these subsites, revealing the substrate-binding mode, and shows the oligosaccharide-enzyme recognition pattern in detail. Comparison between BglA and BglB crystal structures suggests that oligomerization in BglA can assist in fine-tuning the specificity of the active centre by modulating the loops surrounding the cavity. We have solved the crystal structure of BglB with bound thiocellobiose, a competitive inhibitor, which together with the BglB-cellotetraose complex delineate the general features of the aglycon site. The detailed characterization of the atomic interactions at the aglycon site show a recognition pattern common to all bacterial beta-glucosidases, and presents some differences with the aglycon site in plant beta-glycosidases essentially by means of a different orientation of the basal Trp. The crystal structures of of BglB with a covalently bound inhibitor (derived from 2-fluoroglucoside) and glucose (produced by hydrolysis of the substrate in the crystal), provide additional pictures of the binding events and the intermediates formed during the reaction. Altogether, this information can assist in the understanding of subtle differences of the enzyme mechanism and substrate recognition within this family of enzymes, and consequently it can help in the development of new enzymes with improved activity or specificity.
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Affiliation(s)
- Pablo Isorna
- Grupo de Cristalografía Macromolecular y Biología Estructural, Instituto de Química-Física Rocasolano, CSIC, Serrano 119, 28006-Madrid, Spain
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Lee YC, Jackson PL, Jablonsky MJ, Muccio DD. Conformation of 3'CMP bound to RNase A using TrNOESY. Arch Biochem Biophys 2007; 463:37-46. [PMID: 17416340 DOI: 10.1016/j.abb.2007.02.034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2007] [Accepted: 02/09/2007] [Indexed: 11/30/2022]
Abstract
The conditions for accurately determining distance constraints from TrNOESY data on a small ligand (3'CMP) bound to a small protein (RNase A, <14 kDa) are described. For small proteins, normal TrNOESY conditions of 10:1 ligand:protein or greater can lead to inaccurate structures for the ligand-bound conformation due to the contribution of the free ligand to the TrNOESY signals. By using two ligand:protein ratios (2:1 and 5:1), which give the same distance constraints, a conformation of 3'CMP bound to RNase A was determined (glycosidic torsion angle, chi=-166 degrees ; pseudorotational phase angle, 0 degrees < or = P < or =36 degrees ). Ligand-protein NOESY cross peaks were also observed and used to dock 3'CMP into the binding pocket of the apo-protein (7rsa). After energy minimization, the conformation of the 3'CMP:RNase A complex was similar to the X-ray structure (1 rpf) except that a C3'-endo conformation for the ribose ring (rather than C2'-exo conformation) was found in the TrNOESY structure.
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Affiliation(s)
- Yi-Chien Lee
- National Cancer Institute at Frederick, Laboratory of Medical Chemistry, 376 Boyles Street, Building 376, Frederick, MD 21702, USA
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22
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Gerbst AG, Grachev AA, Shashkov AS, Nifantiev NE. Computation techniques in the conformational analysis of carbohydrates. Russ J Bioorg Chem 2007. [DOI: 10.1134/s1068162007010037] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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23
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Faijes M, Saura-Valls M, Pérez X, Conti M, Planas A. Acceptor-dependent regioselectivity of glycosynthase reactions by Streptomyces E383A β-glucosidase. Carbohydr Res 2006; 341:2055-65. [PMID: 16716271 DOI: 10.1016/j.carres.2006.04.049] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2006] [Revised: 04/27/2006] [Accepted: 04/30/2006] [Indexed: 11/28/2022]
Abstract
The nonnucleophilic mutant E383A beta-glucosidase from Streptomyces sp. has proven to be an efficient glycosynthase enzyme, catalyzing the condensation of alpha-glucosyl and alpha-galactosyl fluoride donors to a variety of acceptors. The enzyme has maximal activity at 45 degrees C, and a pH-dependence reflecting general base catalysis with an apparent kinetic pKa of 7.2. The regioselectivity of the new glycosidic linkage depends unexpectedly on the acceptor substrate. With aryl monosaccharide acceptors, beta-(1-->3) disaccharides are obtained in good to excellent yields, thus expanding the synthetic products available with current exo-glycosynthases. With xylopyranosyl acceptor, regioselectivity is poorer and results in the formation of a mixture of beta-(1-->3) and beta-(1-->4) linkages. In contrast, disaccharide acceptors produce exclusively beta-(1-->4) linkages. Therefore, the presence of a glycosyl unit in subsite +II redirects regioselectivity from beta-(1-->3) to beta-(1-->4). To improve operational performance, the E383A mutant was immobilized on a Ni2+-chelating Sepharose resin. Immobilization did not increase stability to pH and organic solvents, but the operational stability and storage stability were clearly enhanced for recycling and scaling-up.
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Affiliation(s)
- Magda Faijes
- Laboratory of Biochemistry, Institut Químic de Sarrià, Universitat Ramon Llull, Via Augusta 390, E-08017 Barcelona, Spain
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Khiar N, Serrano Araújo C, Suárez B, Fernández I. Sulfur–Sulfur-Based Ligands Derived fromD-Sugars: Synthesis of PdII Complexes, Application in Palladium-Catalyzed Allylic Alkylation for the Synthesis of Both Members of Enantiomer Pairs, and Structural Studies. European J Org Chem 2006. [DOI: 10.1002/ejoc.200500651] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Rich JR, Wakarchuk WW, Bundle DR. Chemical and Chemoenzymatic Synthesis of S-Linked Ganglioside Analogues and Their Protein Conjugates for Use as Immunogens. Chemistry 2006; 12:845-58. [PMID: 16196067 DOI: 10.1002/chem.200500518] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Analogues of the tumor-associated gangliosides GM(3) and GM(2) containing terminal S-linked neuraminic acid residues and an amino terminated, truncated ceramide homologue have been synthesized and conjugated to a protein. The synthesis involved coupling of a S-linked sialyl alpha(2-->3) galactose disaccharide with a glucosyl sphingosine analogue, followed by elaboration and deprotection to give amino-terminated glycosyl ceramide 1. Glycosyltransferase-catalyzed extension of the trisaccharide 1 provided access to the modified GM(2) tetrasaccharide 2 or sulphur-containing GD(3) analogue 30. Owing to their potentially enhanced resistance to endogenous exo-glycoside hydrolases and their inherent non-self character, carbohydrate antigens containing non-reducing terminal thioglycosidic linkages may be more immunogenic than O-linked antigens and may stimulate the production of antibodies capable of recognizing naturally occurring oligosaccharides. Our initial results suggest that in fact these antigens are viable immunogens and furthermore, that immune sera cross reacts with O-gangliosides in the context of a heterologous glycoprotein conjugate.
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Affiliation(s)
- Jamie R Rich
- Alberta Ingenuity Centre for Carbohydrate Science, Department of Chemistry, University of Alberta, Edmonton, Canada
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26
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Bundle DR, Rich JR, Jacques S, Yu HN, Nitz M, Ling CC. Thiooligosaccharide Conjugate Vaccines Evoke Antibodies Specific for Native Antigens. Angew Chem Int Ed Engl 2005; 44:7725-9. [PMID: 16276545 DOI: 10.1002/anie.200502179] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- David R Bundle
- Alberta Ingenuity Centre for Carbohydrate Science, Department of Chemistry, University of Alberta, Edmonton, Canada.
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27
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Bundle DR, Rich JR, Jacques S, Yu HN, Nitz M, Ling CC. Thiooligosaccharide Conjugate Vaccines Evoke Antibodies Specific for Native Antigens. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200502179] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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28
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Chakka N, Johnston BD, Pinto BM. Synthesis and conformational analysis of disaccharide analogues containing disulfide and selenosulfide functionalities in the interglycosidic linkages. CAN J CHEM 2005. [DOI: 10.1139/v05-107] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The synthesis of novel disaccharides containing disulfide (methyl-4-S-(β-D-galactopyranosyl-1'-thio)-4-thio-α-D-glucopyranoside (1)) and selenosulfide (methyl-4-Se-(β-D-galactopyranosyl-1'-thio)-4-seleno-α-D-glucopyranoside (2)) functionalities in the interglycosidic linkages is described. The synthetic strategy relied on the reaction of a β-glycosylthiosulfonate with a carbohydrate thiol or selenol nucleophile. The resulting protected β-dihetero-linked disaccharides were deprotected to give the target compounds. The conformational preferences of these dihetero analogues were inferred from NOESY experiments and line-broadening effects in variable-temperature NMR spectra, and are rationalized in terms of molecular orbital theory. Low-energy conformations of these compounds can populate regions of conformational space not usually occupied by β-linked disaccharides, and offer the possibility for presentation of novel ligand topographies.Key words: disaccharides, disulfides, selenosulfides, interglycosidic linkages, conformations, MO explanation.
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29
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Abstract
[structure: see text] Glycosidase resistant thioglycoside precursors of the melanoma-associated ganglioside GM(2) have been synthesized starting from lactose. Syntheses of several analogues of ganglioside GM(3) and a positional isomer have been developed. These compounds contain thio-linked sialic acid residues and a modified ceramide aglycon functionalized for coupling to proteins, surfaces, or matrices. The hydrolytic stability of these oligosaccharides enhances the immunogenicity of the corresponding conjugate vaccines by ensuring their integrity in the acidic compartments of antigen processing cells.
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Affiliation(s)
- Jamie R Rich
- Alberta Ingenuity Centre for Carbohydrate Science, Department of Chemistry, University of Alberta, Edmonton, AB T6G 2G2, Canada.
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30
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Khiar N, Fernández I, Araújo CS, Rodríguez JA, Suárez B, Alvarez E. Highly diastereoselective oxidation of 2-amino-2-deoxy-1-thio-beta-D-glucopyranosides: synthesis of imino sulfinylglycosides. J Org Chem 2003; 68:1433-42. [PMID: 12585884 DOI: 10.1021/jo026519q] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A synthetic route to imino thioglycosides and to imino sulfinylglycosides has been developed. A detailed study on the diastereoselective oxidation of 2-amino-2-deoxy-1-thio-beta-D-glucopyranosides is reported. It has been shown that the stereochemical outcome of the oxidation is highly dependent on the protective group of the amine function. While the oxidation of iminothioglycosides is slightly diastereoselective (up to 30% de in favor of the R(S) sulfoxide), a single isomer is obtained in the case of tetrachlorophthalimido derivatives. The absolute configuration of the sulfinyl glycoside was ascertained by NMR analysis using our recent model on the basis of the exo-anomeric effect corroborated by X-ray crystallography.
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Affiliation(s)
- Noureddine Khiar
- Instituto de Investigaciones Químicas, C.S.I.C.-Universidad de Sevilla, c/. Américo Vespucio, s/n., Isla de la Cartuja, 41092 Sevilla, Spain.
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31
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Nitz M, Ling CC, Otter A, Cutler JE, Bundle DR. The unique solution structure and immunochemistry of the Candida albicans beta -1,2-mannopyranan cell wall antigens. J Biol Chem 2002; 277:3440-6. [PMID: 11700318 DOI: 10.1074/jbc.m109274200] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Synthetic oligomers of the antigenic Candida albicans (1-->2)-beta-mannopyranans adopt a compact solution conformation that leads to numerous inter-residue nuclear Overhauser effects, including unprecedented nuclear Overhauser effects between n and n + 3 residues. In excellent agreement with experimentally determined distances, unrestrained molecular dynamics point to a single family of conformations that approximate a compact helical motif with a three-residue repeat for this unique homopolymer. When the synthetic di- to hexasaccharides were employed as inhibitors of monoclonal antibodies, which protect mice against a lethal dose of the yeast pathogen, a novel pattern of inhibitor activity was observed. Instead of the paradigm first reported by Kabat (Kabat, E. A. (1962) Fed. Proc. 21, 694-701; Kabat, E. A. (1966) J. Immunol. 97, 1-11), wherein homo-oligosaccharides exhibit increasing inhibitory activity with increasing size, here the maximum activity is reached for di- and trisaccharides and diminishes significantly for tetra-, penta-, and hexasaccharides. These immunochemical data correlate with the ordered conformation of the beta-1,2-linked mannopyranan and imply that a uniquely small antigenic determinant has potential as a component of synthetic conjugate vaccines against Candida albicans.
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Affiliation(s)
- Mark Nitz
- Department of Chemistry, the University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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Vallmitjana M, Ferrer-Navarro M, Planell R, Abel M, Ausín C, Querol E, Planas A, Pérez-Pons JA. Mechanism of the family 1 beta-glucosidase from Streptomyces sp: catalytic residues and kinetic studies. Biochemistry 2001; 40:5975-82. [PMID: 11352732 DOI: 10.1021/bi002947j] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The Streptomyces sp. beta-glucosidase (Bgl3) is a retaining glycosidase that belongs to family 1 glycosyl hydrolases. Steady-state kinetics with p-nitrophenyl beta-D-glycosides revealed that the highest k(cat)/K(M) values are obtained with glucoside (with strong substrate inhibition) and fucoside (with no substrate inhibition) substrates and that Bgl3 has 10-fold glucosidase over galactosidase activity. Reactivity studies by means of a Hammett analysis using a series of substituted aryl beta-glucosides gave a biphasic plot log k(cat) vs pK(a) of the phenol aglycon: a linear region with a slope of beta(lg) = -0.8 for the less reactive substrates (pK(a) > 8) and no significant dependence for activated substrates (pK(a) < 8). Thus, according to the two-step mechanism of retaining glycosidases, formation of the glycosyl-enzyme intermediate is rate limiting for the former substrates, while hydrolysis of the intermediate is for the latter. To identify key catalytic residues and on the basis of sequence similarity to other family 1 beta-glucosidases, glutamic acids 178 and 383 were changed to glutamine and alanine by site-directed mutagenesis. Mutation of Glu178 to Gln and Ala yielded enzymes with 250- and 3500-fold reduction in their catalytic efficiencies, whereas larger reduction (10(5)-10(6)-fold) were obtained for mutants at Glu383. The functional role of both residues was probed by a chemical rescue methodology based on activation of the inactive Ala mutants by azide as exogenous nucleophile. The E178A mutant yielded the beta-glucosyl azide adduct (by (1)H NMR) with a 200-fold increase on k(cat) for the 2,4-dinitrophenyl glucoside but constant k(cat)/K(M) on azide concentration. On the other hand, the E383A mutant with the same substrate gave the alpha-glucosyl azide product and a 100-fold increase in k(cat) at 1 M azide. In conclusion, Glu178 is the general acid/base catalyst and Glu383 the catalytic nucleophile. The results presented here indicate that Bgl3 beta-glucosidase displays kinetic and mechanistic properties similar to other family 1 enzymes analyzed so far. Subtle differences in behavior would lie in the fine and specific architecture of their respective active sites.
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Affiliation(s)
- M Vallmitjana
- Institut de Biologia Fonamental "Vicent Villar i Palasí" and Dept Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
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33
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Jiménez-Barbero J, Demange R, Schenk K, Vogel P. Synthesis and solution conformational analysis of 2,3-anhydro-3-C-[(1R)-2,6-anhydro-1-deoxy-1-fluoro-D-glycero-D-gulo-heptitol-1-C-yl]-beta-D-gulo-furanose: first example of a monofluoromethylene-linked C-disaccharide. J Org Chem 2001; 66:5132-8. [PMID: 11463266 DOI: 10.1021/jo0102462] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Condensation of 2,3,4,6-tetra-O-benzyl-beta-D-glucopyranosylcarbaldehyde with isolevoglucosenone induced by Et(2)AlI, followed by epoxidation, gave an aldol that was fluorinated into a monofluoromethylene C-glucopyranoside that was converted into the title C-disaccharide 1. Its conformational behavior in water has been studied by using a combination of NMR spectroscopy (J and NOE data) and molecular mechanics calculations.
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Affiliation(s)
- J Jiménez-Barbero
- Section de Chimie, Université de Lausanne, BCH, CH-1015 Lausanne-Dorigny, Switzerland
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Carpintero M, Fernández-Mayoralas A, Jiménez-Barbero J. The Conformational Behaviour of Fucosyl and Carbafucosyl Mimetics in the Free and in the Protein-Bound States. European J Org Chem 2001. [DOI: 10.1002/1099-0690(200102)2001:4<681::aid-ejoc681>3.0.co;2-e] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Montero E, García-Herrero A, Asensio J, Hirai K, Ogawa S, Santoyo-González F, Cañada F, Jiménez-Barbero J. The Conformational Behaviour of Non-Hydrolizable Lactose Analogues: The Thioglycoside, Carbaglycoside, and Carba-Iminoglycoside Cases. European J Org Chem 2000. [DOI: 10.1002/(sici)1099-0690(200005)2000:10<1945::aid-ejoc1945>3.0.co;2-g] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Weimar T, Kreis UC, Andrews JS, Pinto B. Conformational analysis of maltoside heteroanalogues using high-quality NOE data and molecular mechanics calculations. Flexibility as a function of the interglycosidic chalcogen atom. Carbohydr Res 1999; 315:222-33. [DOI: 10.1016/s0008-6215(99)00011-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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