1
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Chen X. Enabling Chemoenzymatic Strategies and Enzymes for Synthesizing Sialyl Glycans and Sialyl Glycoconjugates. Acc Chem Res 2024; 57:234-246. [PMID: 38127793 PMCID: PMC10795189 DOI: 10.1021/acs.accounts.3c00614] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 12/04/2023] [Accepted: 12/04/2023] [Indexed: 12/23/2023]
Abstract
Sialic acids are fascinating negatively charged nine-carbon monosaccharides. Sialic acid-containing glycans and glycoconjugates are structurally diverse, functionally important, and synthetically challenging molecules. We have developed highly efficient chemoenzymatic strategies that combine the power of chemical synthesis and enzyme catalysis to make sialic acids, sialyl glycans, sialyl glycoconjugates, and their derivatives more accessible, enabling the efforts to explore their functions and applications. The Account starts with a brief description of the structural diversity and the functional importance of naturally occurring sialic acids and sialosides. The development of one-pot multienzyme (OPME) chemoenzymatic sialylation strategies is then introduced, highlighting its advantages in synthesizing structurally diverse sialosides with a sialyltransferase donor substrate engineering tactic. With the strategy, systematic access to sialosides containing different sialic acid forms with modifications at C3/4/5/7/8/9, various internal glycans, and diverse sialyl linkages is now possible. Also briefly described is the combination of the OPME sialylation strategy with bacterial sialidases for synthesizing sialidase inhibitors. With the goal of simplifying the product purification process for enzymatic glycosylation reactions, glycosphingolipids that contain a naturally existing hydrophobic tag are attractive targets for chemoenzymatic total synthesis. A user-friendly highly efficient chemoenzymatic strategy is developed which involves three main processes, including chemical synthesis of lactosyl sphingosine as a water-soluble hydrophobic tag-containing intermediate, OPME enzymatic extension of its glycan component with a single C18-cartridge purification of the product, followed by a facile chemical acylation reaction. The strategy allows the introduction of different sialic acid forms and diverse fatty acyl chains into the products. Gram-scale synthesis has been demonstrated. OPME sialylation has also been demonstrated for the chemoenzymatic synthesis of sialyl glycopeptides and in vitro enzymatic N-glycan processing for the formation of glycoproteins with disialylated biantennary complex-type N-glycans. For synthesizing human milk oligosaccharides (HMOs) which are glycans with a free reducing end, acceptor substrate engineering and process engineering strategies are developed, which involve the design of a hydrophobic tag that can be easily installed into the acceptor substrate to allow facile purification of the product from enzymatic reactions and can be conveniently removed in the final step to produce target molecules. The process engineering involves heat-inactivation of enzymes in the intermediate steps in multistep OPME reactions for the production of long-chain sialoside targets in a single reaction pot and with a single C18-cartridge purification process. In addition, a chemoenzymatic synthon strategy has been developed. It involves the design of a derivative of the sialyltransferase donor substrate precursor, which is tolerated by enzymes in OPME reactions, introduced to enzymatic products, and then chemically converted to the desired target structures in the final step. The chemoenzymatic synthon approach has been used together with the acceptor substrate engineering method in the synthesis of complex bacterial glycans containing sialic acids, legionaminic acids, and derivatives. The biocatalysts characterized and their engineered mutants developed by the Chen group are described, with highlights on synthetically useful enzymes. We anticipate further development of chemoenzymatic strategies and biocatalysts to enable exploration of the sialic acid space.
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Affiliation(s)
- Xi Chen
- Department of Chemistry, University of California, Davis, California 95616, United States
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2
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Rivollier P, Samain E, Armand S, Jeacomine I, Richard E, Fort S. Synthesis of Neuraminidase-Resistant Sialyllactose Mimetics from N-Acyl Mannosamines using Metabolically Engineered Escherichia coli. Chemistry 2023; 29:e202301555. [PMID: 37294058 DOI: 10.1002/chem.202301555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 06/07/2023] [Accepted: 06/09/2023] [Indexed: 06/10/2023]
Abstract
Herein, we describe the efficient gram-scale synthesis of α2,3- and α2,6-sialyllactose oligosaccharides as well as mimetics from N-acyl mannosamines and lactose in metabolically engineered bacterial cells grown at high cell density. We designed new Escherichia coli strains co-expressing sialic acid synthase and N-acylneuraminate cytidylyltransferase from Campylobacter jejuni together with the α2,3-sialyltransferase from Neisseria meningitidis or the α2,6-sialyltransferase from Photobacterium sp. JT-ISH-224. Using their mannose transporter, these new strains actively internalized N-acetylmannosamine (ManNAc) and its N-propanoyl (N-Prop), N-butanoyl (N-But) and N-phenylacetyl (N-PhAc) analogs and converted them into the corresponding sialylated oligosaccharides, with overall yields between 10 % and 39 % (200-700 mg.L-1 of culture). The three α2,6-sialyllactose analogs showed similar binding affinity for Sambucus nigra SNA-I lectin as for the natural oligosaccharide. They also proved to be stable competitive inhibitors of Vibrio cholerae neuraminidase. These N-acyl sialosides therefore hold promise for the development of anti-adhesion therapy against influenza viral infections.
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Affiliation(s)
- Paul Rivollier
- Univ. Grenoble Alpes, CNRS, CERMAV, 38000, Grenoble, France
| | - Eric Samain
- Univ. Grenoble Alpes, CNRS, CERMAV, 38000, Grenoble, France
| | - Sylvie Armand
- Univ. Grenoble Alpes, CNRS, CERMAV, 38000, Grenoble, France
| | | | | | - Sébastien Fort
- Univ. Grenoble Alpes, CNRS, CERMAV, 38000, Grenoble, France
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3
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Protein Engineering of Pasteurella multocida α2,3-Sialyltransferase with Reduced α2,3-Sialidase Activity and Application in Synthesis of 3′-Sialyllactose. Catalysts 2022. [DOI: 10.3390/catal12060579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Sialyltransferases are key enzymes for the production of sialosides. The versatility of Pasteurella multocida α2,3-sialyltransferase 1 (PmST1) causes difficulties in the efficient synthesis of α2,3-linked sialylatetd compounds, especial its α2,3-sialidase activity. In the current study, the α2,3-sialidase activity of PmST1 was further reduced by rational design-based protein engineering. Three double mutants PMG1 (M144D/R313Y), PMG2 (M144D/R313H) and PMG3 (M144D/R313N) were designed and constructed using M144D as the template and kinetically investigated. In comparison with M144D, the α2,3-sialyltransferase activity of PMG2 was enhanced by 1.4-fold, while its α2,3-sialidase activity was reduced by 4-fold. Two PMG2-based triple mutants PMG2-1 (M144D/R313H/T265S) and PMG2-2 (M144D/R313H/E271F) were then designed, generated and characterized. Compared with PMG2, triple mutants showed slightly improved α2,3-sialyltransferase activity, but their α2,3-sialidase activities were increased by 2.1–2.9 fold. In summary, PMG2 was used for preparative-scale production of 3′-SL (3′-sialyllactose) with a yield of >95%. These new PmST1 mutants could be potentially utilized for efficient synthesis of α2,3-linked sialosides. This work provides a guide to designing and constructing efficient sialyltransferases.
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4
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Nejatie A, Colombo C, Hakak‐Zargar B, Bennet AJ. A Mechanistic Study on the Non‐enzymatic Hydrolysis of Kdn Glycosides. European J Org Chem 2022. [DOI: 10.1002/ejoc.202101387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Ali Nejatie
- Department of Chemistry Simon Fraser University 8888 University Drive Burnaby British Columbia V5A 1S6 Canada
| | - Cinzia Colombo
- Department of Chemistry Simon Fraser University 8888 University Drive Burnaby British Columbia V5A 1S6 Canada
| | - Benyamin Hakak‐Zargar
- Department of Chemistry Simon Fraser University 8888 University Drive Burnaby British Columbia V5A 1S6 Canada
| | - Andrew J. Bennet
- Department of Chemistry Simon Fraser University 8888 University Drive Burnaby British Columbia V5A 1S6 Canada
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5
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Chinoy ZS, Montembault E, Moremen KW, Royou A, Friscourt F. Impacting Bacterial Sialidase Activity by Incorporating Bioorthogonal Chemical Reporters onto Mammalian Cell-Surface Sialosides. ACS Chem Biol 2021; 16:2307-2314. [PMID: 34590826 DOI: 10.1021/acschembio.1c00469] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Bioorthogonal chemical reporters, in synergy with click chemistry, have emerged as a key technology for tagging complex glycans in living cells. This strategy relies on the fact that bioorthogonal chemical reporters are highly reactive species while being biologically noninvasive. Here, we report that chemical reporters and especially sydnones may have, on the contrary, enormous impact on biomolecule processing enzymes. More specifically, we show that editing cell-surface sialic acid-containing glycans (sialosides) with bioorthogonal chemical reporters can significantly affect the activity of bacterial sialidases, enzymes expressed by bacteria during pathogenesis for cleaving sialic acid sugars from mammalian cell-surface glycans. Upon screening various chemical reporters, as well as their position on the sialic acid residue, we identified that pathogenic bacterial sialidases were unable to cleave sialosides displaying a sydnone at the 5-position of sialic acids in vitro as well as in living cells. This study highlights the importance of investigating more systematically the metabolic fate of glycoconjugates modified with bioorthogonal reporters.
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Affiliation(s)
- Zoeisha S. Chinoy
- Institut Européen de Chimie et Biologie, Université de Bordeaux, 2 rue Robert Escarpit, 33607 Pessac, France
- Institut des Sciences Moléculaires, CNRS UMR5255, 33405 Talence, France
| | - Emilie Montembault
- Institut Européen de Chimie et Biologie, Université de Bordeaux, 2 rue Robert Escarpit, 33607 Pessac, France
- Institut de Biochimie et Génétique Cellulaires, CNRS UMR5095, 33077 Bordeaux, France
| | - Kelley W. Moremen
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, United States
- Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602, United States
| | - Anne Royou
- Institut Européen de Chimie et Biologie, Université de Bordeaux, 2 rue Robert Escarpit, 33607 Pessac, France
- Institut de Biochimie et Génétique Cellulaires, CNRS UMR5095, 33077 Bordeaux, France
| | - Frédéric Friscourt
- Institut Européen de Chimie et Biologie, Université de Bordeaux, 2 rue Robert Escarpit, 33607 Pessac, France
- Institut des Sciences Moléculaires, CNRS UMR5255, 33405 Talence, France
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6
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Council CE, Kilpin KJ, Gusthart JS, Allman SA, Linclau B, Lee SS. Enzymatic glycosylation involving fluorinated carbohydrates. Org Biomol Chem 2021; 18:3423-3451. [PMID: 32319497 DOI: 10.1039/d0ob00436g] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Fluorinated carbohydrates, where one (or more) fluorine atom(s) have been introduced into a carbohydrate structure, typically through deoxyfluorination chemistry, have a wide range of applications in the glycosciences. Fluorinated derivatives of galactose, glucose, N-acetylgalactosamine, N-acetylglucosamine, talose, fucose and sialic acid have been employed as either donor or acceptor substrates in glycosylation reactions. Fluorinated donors can be synthesised by synthetic methods or produced enzymatically from chemically fluorinated sugars. The latter process is mediated by enzymes such as kinases, phosphorylases and nucleotidyltransferases. Fluorinated donors produced by either method can subsequently be used in glycosylation reactions mediated by glycosyltransferases, or phosphorylases yielding fluorinated oligosaccharide or glycoconjugate products. Fluorinated acceptor substrates are typically synthesised chemically. Glycosyltransferases are most commonly used in conjunction with natural donors to further elaborate fluorinated acceptor substrates. Glycoside hydrolases are used with either fluorinated donors or acceptors. The activity of enzymes towards fluorinated sugars is often lower than towards the natural sugar substrates irrespective of donor or acceptor. This may be in part attributed to elimination of the contribution of the hydroxyl group to the binding of the substrate to enzymes. However, in many cases, enzymes still maintain a significant activity, and reactions may be optimised where necessary, enabling enzymes to be used more successfully in the production of fluorinated carbohydrates. This review describes the current state of the art regarding chemoenzymatic production of fluorinated carbohydrates, focusing specifically on examples of the enzymatic production of activated fluorinated donors and enzymatic glycosylation involving fluorinated sugars as either glycosyl donors or acceptors.
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Affiliation(s)
- Claire E Council
- School of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, UK.
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7
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Yu H, Gadi MR, Bai Y, Zhang L, Li L, Yin J, Wang PG, Chen X. Chemoenzymatic Total Synthesis of GM3 Gangliosides Containing Different Sialic Acid Forms and Various Fatty Acyl Chains. J Org Chem 2021; 86:8672-8682. [PMID: 34152144 DOI: 10.1021/acs.joc.1c00450] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Gangliosides are sialic acid-containing glycosphingolipids that have been found in the cell membranes of all vertebrates. Their important biological functions are contributed by both the glycan and the ceramide lipid components. GM3 is a major ganglioside and a precursor for many other more complex gangliosides. To obtain structurally diverse GM3 gangliosides containing various sialic acid forms and different fatty acyl chains in low cost, an improved process was developed to chemically synthesize lactosyl sphingosine from an inexpensive l-serine derivative. It was then used to obtain GM3 sphingosines from diverse modified sialic acid precursors by an efficient one-pot multienzyme sialylation system containing Pasteurella multocida sialyltransferase 3 (PmST3) with in situ generation of sugar nucleotides. A highly effective chemical acylation and facile C18-cartridge purification process was then used to install fatty acyl chains of varying lengths and different modifications. The chemoenzymatic method represents a powerful total synthetic strategy to access a library of structurally defined GM3 gangliosides to explore their functions.
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Affiliation(s)
- Hai Yu
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
| | - Madhusudhan Reddy Gadi
- Department of Chemistry, Georgia State University, Atlanta, Georgia 30303, United States
| | - Yuanyuan Bai
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
| | - Libo Zhang
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
| | - Lei Li
- Department of Chemistry, Georgia State University, Atlanta, Georgia 30303, United States
| | - Jun Yin
- Department of Chemistry, Georgia State University, Atlanta, Georgia 30303, United States.,Center for Diagnostics & Therapeutics, Georgia State University, Atlanta, Georgia 30303, United States
| | - Peng G Wang
- Department of Chemistry, Georgia State University, Atlanta, Georgia 30303, United States
| | - Xi Chen
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
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8
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Geissner A, Baumann L, Morley TJ, Wong AKO, Sim L, Rich JR, So PPL, Dullaghan EM, Lessard E, Iqbal U, Moreno M, Wakarchuk WW, Withers SG. 7-Fluorosialyl Glycosides Are Hydrolysis Resistant but Readily Assembled by Sialyltransferases Providing Easy Access to More Metabolically Stable Glycoproteins. ACS CENTRAL SCIENCE 2021; 7:345-354. [PMID: 33655072 PMCID: PMC7908025 DOI: 10.1021/acscentsci.0c01589] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Indexed: 05/04/2023]
Abstract
The maintenance of therapeutic glycoproteins within the circulatory system is associated, in large part, with the integrity of sialic acids as terminal sugars on the glycans. Glycoprotein desialylation, either by spontaneous cleavage or through host sialidases, leads to protein clearance, mainly through the liver. Thus, the installation of minimally modified sialic acids that are hydrolysis-resistant yet biologically equivalent should lead to increased circulatory half-lives and improved pharmacokinetic profiles. Here we describe the chemoenzymatic synthesis of CMP-sialic acid sugar donors bearing fluorine atoms at the 7-position, starting from the corresponding 4-deoxy-4-fluoro-N-acetylhexosamine precursors. For the derivative with natural stereochemistry we observe efficient glycosyl transfer by sialyltransferases, along with improved stability of the resultant 7-fluorosialosides toward spontaneous hydrolysis (3- to 5-fold) and toward cleavage by GH33 sialidases (40- to 250-fold). Taking advantage of the rapid transfer of 7-fluorosialic acid by sialyltransferases, we engineered the O-glycan of Interferon α-2b and the N-glycans of the therapeutic glycoprotein α1-antitrypsin. Studies of the uptake of the glyco-engineered α1-antitrypsin by HepG2 liver cells demonstrated the bioequivalence of 7-fluorosialic acid to sialic acid in suppressing interaction with liver cell lectins. In vivo pharmacokinetic studies reveal enhanced half-life of the protein decorated with 7-fluorosialic acid relative to unmodified sialic acid in the murine circulatory system. 7-Fluorosialylation therefore offers considerable promise as a means of prolonging circulatory half-lives of glycoproteins and may pave the way toward biobetters for therapeutic use.
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Affiliation(s)
- Andreas Geissner
- Department
of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada
| | - Lars Baumann
- Department
of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada
| | - Thomas J. Morley
- Department
of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada
| | - Andrew K. O. Wong
- Department
of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada
| | - Lyann Sim
- Department
of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada
| | - Jamie R. Rich
- Department
of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada
| | - Pauline P. L. So
- AdMare
BioInnovations, 2405
Wesbrook Mall, Vancouver, BC V6T 1Z3, Canada
| | - Edie M. Dullaghan
- AdMare
BioInnovations, 2405
Wesbrook Mall, Vancouver, BC V6T 1Z3, Canada
| | - Etienne Lessard
- National
Research Council Canada, Human Health Therapeutics, Ottawa, ON K1A 0R6, Canada
| | - Umar Iqbal
- National
Research Council Canada, Human Health Therapeutics, Ottawa, ON K1A 0R6, Canada
| | - Maria Moreno
- National
Research Council Canada, Human Health Therapeutics, Ottawa, ON K1A 0R6, Canada
| | - Warren W. Wakarchuk
- Department
of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Stephen G. Withers
- Department
of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada
- Tel.: (604) 822-3402. Fax: (604) 822-8869. E-mail:
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9
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Linclau B, Ardá A, Reichardt NC, Sollogoub M, Unione L, Vincent SP, Jiménez-Barbero J. Fluorinated carbohydrates as chemical probes for molecular recognition studies. Current status and perspectives. Chem Soc Rev 2021; 49:3863-3888. [PMID: 32520059 DOI: 10.1039/c9cs00099b] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
This review provides an extensive summary of the effects of carbohydrate fluorination with regard to changes in physical, chemical and biological properties with respect to regular saccharides. The specific structural, conformational, stability, reactivity and interaction features of fluorinated sugars are described, as well as their applications as probes and in chemical biology.
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Affiliation(s)
- Bruno Linclau
- School of Chemistry, University of Southampton, Highfield, Southampton SO171BJ, UK
| | - Ana Ardá
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), 48160 Derio, Spain.
| | | | - Matthieu Sollogoub
- Sorbonne Université, CNRS, Institut Parisien de Chimie Moléculaire, UMR 8232, 4 place Jussieu, 75005 Paris, France
| | - Luca Unione
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands
| | - Stéphane P Vincent
- Department of Chemistry, Laboratory of Bio-organic Chemistry, University of Namur (UNamur), B-5000 Namur, Belgium
| | - Jesús Jiménez-Barbero
- CIC bioGUNE, Basque Research and Technology Alliance (BRTA), 48160 Derio, Spain. and Ikerbasque, Basque Foundation for Science, Maria Diaz de Haro 3, 48013 Bilbao, Spain and Department of Organic Chemistry II, Faculty of Science and Technology, UPV/EHU, 48940 Leioa, Spain
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10
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Yuan L, Zhao Y, Sun XL. Sialidase substrates for Sialdiase assays - activity, specificity, quantification and inhibition. Glycoconj J 2020; 37:513-531. [PMID: 32813176 DOI: 10.1007/s10719-020-09940-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 07/08/2020] [Accepted: 08/06/2020] [Indexed: 12/01/2022]
Abstract
Sialidases are glycosidases responsible for the removal of sialic acid (Sia) residues (desialylation) from glycan portions of either glycoproteins or glycolipids. By desialylation, sialidases are able to modulate the functionality and stability of the Sia-containing molecules and are involved in both physiological and pathological pathways. Therefore, evaluation of sialidase activity and specificity is important for understanding the biological significance of desialylation by sialidases and its function and the related molecular mechanisms of the physiological and pathological pathways. In addition, it is essential for developing novel mechanisms and approaches for disease treatment and diagnosis and pathogen detection as well. This review summarizes the most recent sialidase substrates for evaluating sialidase activity and specificity and screening sialidase inhibitors, including (i) general sialidase substrates, (ii) specific sialidase substrates, (iii) native sialidase substrates and (iv) cellular sialidase substrates. This review also provides a brief introduction of recent instrumental methods for quantifying the sialidase activity, such as UV, fluorescence, HPLC and LC-MS methods.
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Affiliation(s)
- Lei Yuan
- Department of Chemistry, Chemical and Biomedical Engineering and Center for Gene Regulation in Health and Disease (GRHD), Cleveland State University, 2121 Euclid Avenue, Cleveland, OH, 44115, USA.,School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang, 110016, People's Republic of China
| | - Yu Zhao
- Department of Chemistry, Chemical and Biomedical Engineering and Center for Gene Regulation in Health and Disease (GRHD), Cleveland State University, 2121 Euclid Avenue, Cleveland, OH, 44115, USA
| | - Xue-Long Sun
- Department of Chemistry, Chemical and Biomedical Engineering and Center for Gene Regulation in Health and Disease (GRHD), Cleveland State University, 2121 Euclid Avenue, Cleveland, OH, 44115, USA.
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11
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Kooner AS, Yu H, Chen X. Synthesis of N-Glycolylneuraminic Acid (Neu5Gc) and Its Glycosides. Front Immunol 2019; 10:2004. [PMID: 31555264 PMCID: PMC6724515 DOI: 10.3389/fimmu.2019.02004] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 08/07/2019] [Indexed: 12/12/2022] Open
Abstract
Sialic acids constitute a family of negatively charged structurally diverse monosaccharides that are commonly presented on the termini of glycans in higher animals and some microorganisms. In addition to N-acetylneuraminic acid (Neu5Ac), N-glycolyl neuraminic acid (Neu5Gc) is among the most common sialic acid forms in nature. Nevertheless, unlike most animals, human cells loss the ability to synthesize Neu5Gc although Neu5Gc-containing glycoconjugates have been found on human cancer cells and in various human tissues due to dietary incorporation of Neu5Gc. Some pathogenic bacteria also produce Neu5Ac and the corresponding glycoconjugates but Neu5Gc-producing bacteria have yet to be found. In addition to Neu5Gc, more than 20 Neu5Gc derivatives have been found in non-human vertebrates. To explore the biological roles of Neu5Gc and its naturally occurring derivatives as well as the corresponding glycans and glycoconjugates, various chemical and enzymatic synthetic methods have been developed to obtain a vast array of glycosides containing Neu5Gc and/or its derivatives. Here we provide an overview on various synthetic methods that have been developed. Among these, the application of highly efficient one-pot multienzyme (OPME) sialylation systems in synthesizing compounds containing Neu5Gc and derivatives has been proven as a powerful strategy.
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Affiliation(s)
| | - Hai Yu
- Department of Chemistry, University of California, Davis, Davis, CA, United States
| | - Xi Chen
- Department of Chemistry, University of California, Davis, Davis, CA, United States
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12
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Li W, Santra A, Yu H, Slack TJ, Muthana MM, Shi D, Liu Y, Chen X. 9-Azido-9-deoxy-2,3-difluorosialic Acid as a Subnanomolar Inhibitor against Bacterial Sialidases. J Org Chem 2019; 84:6697-6708. [PMID: 31083938 DOI: 10.1021/acs.joc.9b00385] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A library of 2(a),3(a/e)-difluorosialic acids and their C-5 and/or C-9 derivatives were chemoenzymatically synthesized. Pasteurella multocida sialic acid aldolase (PmAldolase), but not its Escherichia coli homologue (EcAldolase), was found to catalyze the formation of C5-azido analogue of 3-fluoro(a)-sialic acid. In comparison, both PmAldolase and EcAldolase could catalyze the synthesis of 3-fluoro(a/e)-sialic acids and their C-9 analogues although PmAldolase was generally more efficient. The chemoenzymatically synthesized 3-fluoro(a/e)-sialic acid analogues were purified and chemically derivatized to form the desired difluorosialic acids and derivatives. Inhibition studies against several bacterial sialidases and a recombinant human cytosolic sialidase hNEU2 indicated that sialidase inhibition was affected by the C-3 fluorine stereochemistry and derivatization at C-5 and/or C-9 of the inhibitor. Opposite to that observed for influenza A virus sialidases and hNEU2, compounds with axial fluorine at C-3 were better inhibitors (up to 100-fold) against bacterial sialidases compared to their 3F-equatorial counterparts. While C-5-modified compounds were less-efficient antibacterial sialidase inhibitors, 9-N3-modified 2,3-difluoro-Neu5Ac showed increased inhibitory activity against bacterial sialidases. 9-Azido-9-deoxy-2-(e)-3-(a)-difluoro- N-acetylneuraminic acid [2(e)3(a)DFNeu5Ac9N3] was identified as an effective inhibitor with a long effective duration selectively against pathogenic bacterial sialidases from Clostridium perfringens (CpNanI) and Vibrio cholerae.
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Affiliation(s)
- Wanqing Li
- Department of Chemistry , University of California-Davis , One Shields Avenue , Davis , California 95616 , United States
| | - Abhishek Santra
- Department of Chemistry , University of California-Davis , One Shields Avenue , Davis , California 95616 , United States
| | - Hai Yu
- Department of Chemistry , University of California-Davis , One Shields Avenue , Davis , California 95616 , United States
| | - Teri J Slack
- Department of Chemistry , University of California-Davis , One Shields Avenue , Davis , California 95616 , United States
| | | | | | | | - Xi Chen
- Department of Chemistry , University of California-Davis , One Shields Avenue , Davis , California 95616 , United States
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13
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Lo HJ, Krasnova L, Dey S, Cheng T, Liu H, Tsai TI, Wu KB, Wu CY, Wong CH. Synthesis of Sialidase-Resistant Oligosaccharide and Antibody Glycoform Containing α2,6-Linked 3F ax-Neu5Ac. J Am Chem Soc 2019; 141:6484-6488. [PMID: 30969765 DOI: 10.1021/jacs.9b01991] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Fluorinated glycosides are known to resist the glycosidase-catalyzed glycosidic bond cleavage; however, the synthesis of such glycans, especially 3-fluoro-sialic acid (3F-Neu5Ac) containing sialosides, has been a major challenge. Though the enzymatic synthesis of α-2,3-linked 3F-sialosides was reported, until recently there has not been any effective method available for the synthesis of 3F-sialosides in the α-2,6-linkage. In order to understand the biological effect of such modification, we report here a chemical synthesis of 3Fax-Neu5Ac-α2,6-Gal as a building block for the assembly of 3Fax-Neu5Ac-containing sialosides and a representative homogeneous antibody glycoform. Our results showed that the sialosides are stable under sialidase catalysis and the rituximab glycoform with a sialylated complex-type biantennary glycan terminated with 3Fax-Neu5Ac in the α-2,6-linkage (α2,6-F-SCT) has a similar binding avidity as its parent glycoform. These findings open up new opportunities for the development of therapeutic glycoproteins with improved pharmacokinetic parameters.
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Affiliation(s)
- Hong-Jay Lo
- Genomics Research Center , Academia Sinica , 128 Academia Road , Section 2, Nanakang, Taipei 115 , Taiwan.,The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Larissa Krasnova
- The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Supriya Dey
- The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Ting Cheng
- Genomics Research Center , Academia Sinica , 128 Academia Road , Section 2, Nanakang, Taipei 115 , Taiwan
| | - Haitian Liu
- The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Tsung-I Tsai
- The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Kevin Binchia Wu
- The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Chung-Yi Wu
- Genomics Research Center , Academia Sinica , 128 Academia Road , Section 2, Nanakang, Taipei 115 , Taiwan
| | - Chi-Huey Wong
- Genomics Research Center , Academia Sinica , 128 Academia Road , Section 2, Nanakang, Taipei 115 , Taiwan.,The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
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14
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Gilormini PA, Lion C, Vicogne D, Guérardel Y, Foulquier F, Biot C. Chemical glycomics enrichment: imaging the recycling of sialic acid in living cells. J Inherit Metab Dis 2018; 41:515-523. [PMID: 29294191 PMCID: PMC5959963 DOI: 10.1007/s10545-017-0118-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 10/28/2017] [Accepted: 11/20/2017] [Indexed: 01/10/2023]
Abstract
The development of metabolic oligosaccharide engineering (MOE) over the past two decades enabled the bioimaging studies of glycosylation processes in physio-pathological contexts. Herein, we successfully applied the chemical reporter strategy to image the fate of sialylated glycoconjugates in healthy and sialin-deficient patient fibroblasts. This chemical glycomics enrichment is a powerful tool for tracking sialylated glycoconjugates and probing lysosomal recycling capacities. Thus, such strategies appear fundamental for the characterization of lysosomal storage diseases.
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Affiliation(s)
- Pierre André Gilormini
- University Lille, CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, F-59000, Lille, France
| | - Cédric Lion
- University Lille, CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, F-59000, Lille, France
| | - Dorothée Vicogne
- University Lille, CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, F-59000, Lille, France
| | - Yann Guérardel
- University Lille, CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, F-59000, Lille, France
| | - François Foulquier
- University Lille, CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, F-59000, Lille, France.
| | - Christophe Biot
- University Lille, CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, F-59000, Lille, France.
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15
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Tasnima N, Yu H, Li Y, Santra A, Chen X. Chemoenzymatic synthesis of para-nitrophenol (pNP)-tagged α2-8-sialosides and high-throughput substrate specificity studies of α2-8-sialidases. Org Biomol Chem 2018; 15:160-167. [PMID: 27924345 DOI: 10.1039/c6ob02240e] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
para-Nitrophenol (pNP)-tagged α2-8-linked sialosides containing different sialic acid forms were chemoenzymatically synthesized using an efficient one-pot three-enzyme α2-8-sialylation system. The resulting compounds allowed high-throughput substrate specificity studies of the α2-8-sialidase activity of a recombinant human cytosolic sialidase hNEU2 and various bacterial sialidases. The sialoside substrate profiles obtained can be used to guide the selection of suitable sialidases for sialylglycan analysis and for cell and tissue surface glycan modification. They can also be used to guide sialidase inhibitor design.
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Affiliation(s)
- Nova Tasnima
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA.
| | - Hai Yu
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA.
| | - Yanhong Li
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA.
| | - Abhishek Santra
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA.
| | - Xi Chen
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA.
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16
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Xiao A, Li Y, Li X, Santra A, Yu H, Li W, Chen X. Sialidase-catalyzed one-pot multienzyme (OPME) synthesis of sialidase transition-state analogue inhibitors. ACS Catal 2018; 8:43-47. [PMID: 29713561 PMCID: PMC5920526 DOI: 10.1021/acscatal.7b03257] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Sialidase transition state analog inhibitor 2,3-dehydro-2-deoxy-N-acetylneuraminic acid (Neu5Ac2en, DANA) has played a leading role in developing clinically used anti-influenza virus drugs. Taking advantage of the Neu5Ac2en-forming catalytic property of Streptococcus pneumoniae sialidase SpNanC, an effective one-pot multienzyme (OPME) strategy has been developed to directly access Neu5Ac2en and its C-5, C-9, and C-7-analogs from N-acetylmannosamine (ManNAc) and analogs. The obtained Neu5Ac2en analogs can be further derivatized at various positions to generate a larger inhibitor library. Inhibition studies demonstrated improved selectivity of several C-5- or C-9-modified Neu5Ac2en derivatives against several bacterial sialidases. The study provides an efficient enzymatic method to access sialidase inhibitors with improved selectivity.
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Affiliation(s)
- An Xiao
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
| | - Yanhong Li
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
| | - Xixuan Li
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
| | - Abhishek Santra
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
| | - Hai Yu
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
| | - Wanqing Li
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
| | - Xi Chen
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
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17
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Heise T, Büll C, Beurskens DM, Rossing E, de Jonge MI, Adema GJ, Boltje TJ, Langereis JD. Metabolic Oligosaccharide Engineering with Alkyne Sialic Acids Confers Neuraminidase Resistance and Inhibits Influenza Reproduction. Bioconjug Chem 2017. [PMID: 28635265 PMCID: PMC5520103 DOI: 10.1021/acs.bioconjchem.7b00224] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
![]()
Metabolic
incorporation of azide- or alkyne-modified sialic acids
into the cellular glycosylation pathway enables the study of sialoglycan
expression, localization, and trafficking via bioorthogonal chemistry.
Herein, we report that such modifications of the sialic acid sugar
can have a profound influence on their hydrolysis by neuraminidases
(sialidase). Azidoacetyl (Az)-modified sialic acids were prone to
neuraminidase cleavage, whereas propargyloxycarbonyl (Poc)-modified
sialic acids were largely resistant to cleavage. Because the influenza
virus infection cycle depends on the hydrolysis of host-cell-surface
sialic acids, influenza cell-to-cell transmission was strongly reduced
in Poc sialic acid glycoengineered host cells. The use of Poc sialic
acids may disturb biological processes involving neuraminidase cleavage
but also provides perspective for use in applications in which sialic
acid hydrolysis is not desired, such as antibody modification, viral
infection, etc.
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Affiliation(s)
- Torben Heise
- Institute for Molecules and Materials, Radboud University Nijmegen , Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Christian Büll
- Department of Radiation Oncology, Radiotherapy & OncoImmunology Laboratory, Radboudumc , Geert Grooteplein Zuid 32, 6525 GA Nijmegen, The Netherlands
| | - Daniëlle M Beurskens
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University , Universiteitssingel 50, 6229 ER Maastricht, The Netherlands
| | - Emiel Rossing
- Institute for Molecules and Materials, Radboud University Nijmegen , Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Marien I de Jonge
- Laboratory of Pediatric Infectious Diseases, Radboud Center for Infectious Diseases, Radboudumc , Geert Grooteplein Zuid 32, 6525 GA Nijmegen, The Netherlands
| | - Gosse J Adema
- Department of Radiation Oncology, Radiotherapy & OncoImmunology Laboratory, Radboudumc , Geert Grooteplein Zuid 32, 6525 GA Nijmegen, The Netherlands
| | - Thomas J Boltje
- Institute for Molecules and Materials, Radboud University Nijmegen , Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Jeroen D Langereis
- Laboratory of Pediatric Infectious Diseases, Radboud Center for Infectious Diseases, Radboudumc , Geert Grooteplein Zuid 32, 6525 GA Nijmegen, The Netherlands
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18
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Okerblom J, Varki A. Biochemical, Cellular, Physiological, and Pathological Consequences of Human Loss of N-Glycolylneuraminic Acid. Chembiochem 2017; 18:1155-1171. [PMID: 28423240 DOI: 10.1002/cbic.201700077] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Indexed: 12/15/2022]
Abstract
About 2-3 million years ago, Alu-mediated deletion of a critical exon in the CMAH gene became fixed in the hominin lineage ancestral to humans, possibly through a stepwise process of selection by pathogen targeting of the CMAH product (the sialic acid Neu5Gc), followed by reproductive isolation through female anti-Neu5Gc antibodies. Loss of CMAH has occurred independently in some other lineages, but is functionally intact in Old World primates, including our closest relatives, the chimpanzee. Although the biophysical and biochemical ramifications of losing tens of millions of Neu5Gc hydroxy groups at most cell surfaces remains poorly understood, we do know that there are multiscale effects functionally relevant to both sides of the host-pathogen interface. Hominin CMAH loss might also contribute to understanding human evolution, at the time when our ancestors were starting to use stone tools, increasing their consumption of meat, and possibly hunting. Comparisons with chimpanzees within ethical and practical limitations have revealed some consequences of human CMAH loss, but more has been learned by using a mouse model with a human-like Cmah inactivation. For example, such mice can develop antibodies against Neu5Gc that could affect inflammatory processes like cancer progression in the face of Neu5Gc metabolic incorporation from red meats, display a hyper-reactive immune system, a human-like tendency for delayed wound healing, late-onset hearing loss, insulin resistance, susceptibility to muscular dystrophy pathologies, and increased sensitivity to multiple human-adapted pathogens involving sialic acids. Further studies in such mice could provide a model for other human-specific processes and pathologies involving sialic acid biology that have yet to be explored.
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Affiliation(s)
- Jonathan Okerblom
- Biomedical Sciences Graduate Program, University of California in San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0687, USA
| | - Ajit Varki
- Glycobiology Research and Training Center, GRTC) and, Center for Academic Research and Training in Anthropogeny, CARTA), Departments of Medicine and Cellular and Molecular Medicine, University of California in San Diego, La Jolla, CA, 92093-0687, USA
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19
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N-acetylglucosamine 2-Epimerase from Pedobacter heparinus: First Experimental Evidence of a Deprotonation/Reprotonation Mechanism. Catalysts 2016. [DOI: 10.3390/catal6120212] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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20
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Emma MG, Lombardo M, Trombini C, Quintavalla A. The Organocatalytic α-Fluorination of Chiral γ-Nitroaldehydes: the Challenge of Facing the Construction of a Quaternary Fluorinated Stereocenter. European J Org Chem 2016. [DOI: 10.1002/ejoc.201600378] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Marco Giuseppe Emma
- Department of Chemistry “G. Ciamician”; Alma Mater Studiorum; University of Bologna; Via Selmi 2 40126 Bologna Italy
| | - Marco Lombardo
- Department of Chemistry “G. Ciamician”; Alma Mater Studiorum; University of Bologna; Via Selmi 2 40126 Bologna Italy
| | - Claudio Trombini
- Department of Chemistry “G. Ciamician”; Alma Mater Studiorum; University of Bologna; Via Selmi 2 40126 Bologna Italy
| | - Arianna Quintavalla
- Department of Chemistry “G. Ciamician”; Alma Mater Studiorum; University of Bologna; Via Selmi 2 40126 Bologna Italy
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21
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McCombs JE, Kohler JJ. Pneumococcal Neuraminidase Substrates Identified through Comparative Proteomics Enabled by Chemoselective Labeling. Bioconjug Chem 2016; 27:1013-22. [PMID: 26954852 DOI: 10.1021/acs.bioconjchem.6b00050] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Neuraminidases (sialidases) are enzymes that hydrolytically remove sialic acid from sialylated proteins and lipids. Neuraminidases are encoded by a range of human pathogens, including bacteria, viruses, fungi, and protozoa. Many pathogen neuraminidases are virulence factors, indicating that desialylation of host glycoconjugates can be a critical step in infection. Specifically, desialylation of host cell surface glycoproteins can enable these molecules to function as pathogen receptors or can alter signaling through the plasma membrane. Despite these critical effects, no unbiased approaches exist to identify glycoprotein substrates of neuraminidases. Here, we combine previously reported glycoproteomics methods with quantitative proteomics analysis to identify glycoproteins whose sialylation changes in response to neuraminidase treatment. The two glycoproteomics methods-periodate oxidation and aniline-catalyzed oxime ligation (PAL) and galactose oxidase and aniline-catalyzed oxime ligation (GAL)-rely on chemoselective labeling of sialylated and nonsialylated glycoproteins, respectively. We demonstrated the utility of the combined approaches by identifying substrates of two pneumococcal neuraminidases in a human cell line that models the blood-brain barrier. The methods deliver complementary lists of neuraminidase substrates, with GAL identifying a larger number of substrates than PAL (77 versus 17). Putative neuraminidase substrates were confirmed by other methods, establishing the validity of the approach. Among the identified substrates were host glycoproteins known to function in bacteria adherence and infection. Functional assays suggest that multiple desialylated cell surface glycoproteins may act together as pneumococcus receptors. Overall, this method will provide a powerful approach to identify glycoproteins that are desialylated by both purified neuraminidases and intact pathogens.
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Affiliation(s)
- Janet E McCombs
- Department of Biochemistry, The University of Texas Southwestern Medical Center , Dallas, Texas 75390-9038, United States
| | - Jennifer J Kohler
- Department of Biochemistry, The University of Texas Southwestern Medical Center , Dallas, Texas 75390-9038, United States
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22
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McCombs JE, Zou C, Parker RB, Cairo CW, Kohler JJ. Enhanced Cross-Linking of Diazirine-Modified Sialylated Glycoproteins Enabled through Profiling of Sialidase Specificities. ACS Chem Biol 2016; 11:185-92. [PMID: 26541974 DOI: 10.1021/acschembio.5b00775] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Sialic-acid-mediated interactions play critical roles on the cell surface, providing an impetus for the development of methods to study this important monosaccharide. In particular, photo-cross-linking sialic acids incorporated onto cell surfaces have allowed covalent capture of transient interactions between sialic acids and sialic-acid-recognizing proteins via cross-linking. However, natural sialic acids also present on the cell surface compete with photo-cross-linking sialic acids in binding events, limiting cross-linking yields. In order to improve the utility of one such photo-cross-linking sialic acid, SiaDAz, we examined a number of sialidases, enzymes that remove sialic acids from glycoconjugates, to find one that would cleave natural sialic acids but remain inactive toward SiaDAz. Using this sialidase, we improved SiaDAz-mediated cross-linking of an antisialyl Lewis X antibody and of endoglin. This protocol can be applied generally to sialic-acid-mediated interactions and will facilitate identification of sialic acid binding partners.
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Affiliation(s)
- Janet E. McCombs
- Department
of Biochemistry, The University of Texas Southwestern Medical Center, Dallas, Texas 75390-9038, United States
| | - Chunxia Zou
- Alberta
Glycomics Centre, Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Randy B. Parker
- Department
of Biochemistry, The University of Texas Southwestern Medical Center, Dallas, Texas 75390-9038, United States
| | - Christopher W. Cairo
- Alberta
Glycomics Centre, Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Jennifer J. Kohler
- Department
of Biochemistry, The University of Texas Southwestern Medical Center, Dallas, Texas 75390-9038, United States
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23
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Huang K, Wang MM, Kulinich A, Yao HL, Ma HY, Martínez JER, Duan XC, Chen H, Cai ZP, Flitsch SL, Liu L, Voglmeir J. Biochemical characterisation of the neuraminidase pool of the human gut symbiont Akkermansia muciniphila. Carbohydr Res 2015; 415:60-5. [PMID: 26340137 DOI: 10.1016/j.carres.2015.08.001] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 08/09/2015] [Accepted: 08/11/2015] [Indexed: 11/26/2022]
Abstract
Since the isolation and identification of Akkermansia muciniphila one decade ago, much attention has been drawn to this gut bacterium due to its role in obesity and type 2 diabetes. This report describes the discovery and biochemical characterisation of all four putative neuraminidases annotated in the A. muciniphila genome. Recombinantly expressed candidate genes, which were designated Am0705, Am0707, Am1757 and Am2085, were shown to cover complementary pH ranges between 4.0 and 9.5. Temperature optima of the enzymes lay between 37 and 42 °C. All four enzymes were strongly inhibited by Cu(2+) and Zn(2+), and loss of activity after the addition of EDTA suggests that all neuraminidases, with the exception of Am0707, require divalent metal ions for their catalytic function. Chemoenzymatically synthesised α2,3- and α2,6-linked indoyl-sialosides were utilised to determine the regioselectivity and substrate promiscuity of the neuraminidases towards C5-modifications of sialic acids with N-acetyl-, N-glycolyl-, N-propionyl-, or hydroxyl-groups. The combination of simple purification procedures and good activities of some of the characterised neuraminidases makes them potentially interesting as tools in bioanalytical or industrial applications.
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Affiliation(s)
- Kun Huang
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Mao M Wang
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Anna Kulinich
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Hong L Yao
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Hong Y Ma
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, China
| | - Juana E R Martínez
- Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, Manchester, United Kingdom
| | - Xu C Duan
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Huan Chen
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Zhi P Cai
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Sabine L Flitsch
- Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, Manchester, United Kingdom
| | - Li Liu
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China.
| | - Josef Voglmeir
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China.
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24
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Onsirisakul N, Nakakita SI, Boonarkart C, Kongchanagul A, Suptawiwat O, Puthavathana P, Chaichuen K, Kittiniyom K, Suzuki Y, Auewarakul P. Substrate specificity of avian influenza H5N1 neuraminidase. World J Virol 2014; 3:30-36. [PMID: 25396120 PMCID: PMC4229813 DOI: 10.5501/wjv.v3.i4.30] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 09/03/2014] [Accepted: 10/16/2014] [Indexed: 02/05/2023] Open
Abstract
AIM: To characterise neuraminidase (NA) substrate specificity of avian influenza H5N1 strains from humans and birds comparing to seasonal influenza virus.
METHODS: Avian influenza H5N1 strains from humans and birds were recruited for characterising their NA substrate specificity by using a modified commercial fluorescence Amplex Red assay. This method can identify the preference of α2,6-linked sialic acid or α2,3-linked sialic acid. Moreover, to avoid the bias of input virus, reverse genetic virus using NA gene from human isolated H5N1 were generated and used to compare with the seasonal influenza virus. Lastly, the substrate specificity profile was further confirmed by high-performance liquid chromatography (HPLC) analysis of the enzymatic product.
RESULTS: The H5N1 NA showed higher activity on α2,3-linked sialic acid than α2,6-linked (P < 0.0001). To compare the NA activity between the H5N1 and seasonal influenza viruses, reverse genetic viruses carrying the NA of H5N1 viruses and NA from a seasonal H3N2 virus was generated. In these reverse genetic viruses, the NA activity of the H5N1 showed markedly higher activity against α2,3-linked sialic acid than that of the H3N2 virus, whereas the activities on α2,6-linkage were comparable. Interestingly, NA from an H5N1 human isolate that was previously shown to have heamagglutinin (HA) with dual specificity showed reduced activity on α2,3-linkage. To confirm the substrate specificity profile, HPLC analytic of enzymatic product was performed. Similar to Amplex red assay, H5N1 virus showed abundant preference on α2,3-linked sialic acid.
CONCLUSION: H5N1 virus maintains the avian specific NA and NA changes may be needed to accompany changes in HA receptor preference for the viral adaptation to humans.
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25
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Chemoenzymatic synthesis of sialosides containing C7-modified sialic acids and their application in sialidase substrate specificity studies. Carbohydr Res 2014; 389:100-11. [PMID: 24680514 DOI: 10.1016/j.carres.2014.02.021] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Accepted: 02/20/2014] [Indexed: 01/12/2023]
Abstract
Modifications at the glycerol side chain of sialic acid in sialosides modulate their recognition by sialic acid-binding proteins and sialidases. However, limited work has been focused on the synthesis and functional studies of sialosides with C7-modified sialic acids. Here we report chemical synthesis of C4-modified ManNAc and mannose and their application as sialic acid precursors in a highly efficient one-pot three-enzyme system for chemoenzymatic synthesis of α2-3- and α2-6-linked sialyl para-nitrophenyl galactosides in which the C7-hydroxyl group in sialic acid (N-acetylneuraminic acid, Neu5Ac, or 2-keto-3-deoxynonulosonic acid, Kdn) was systematically substituted by -F, -OMe, -H, and -N3 groups. Substrate specificity study of bacterial and human sialidases using the obtained sialoside library containing C7-modified sialic acids showed that sialosides containing C7-deoxy Neu5Ac were selective substrates for all bacterial sialidases tested but not for human NEU2. The information obtained from sialidase substrate specificity can be used to guide the design of new inhibitors that are selective against bacterial sialidases.
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26
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Yi D, He N, Kickstein M, Metzner J, Weiß M, Berry A, Fessner W. Engineering of a Cytidine 5′‐Monophosphate‐Sialic Acid Synthetase for Improved Tolerance to Functional Sialic Acids. Adv Synth Catal 2013. [DOI: 10.1002/adsc.201300568] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Dong Yi
- Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Petersenstrasse 22, 64287 Darmstadt, Germany, Fax: (+49)‐6151‐166636
| | - Ning He
- Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Petersenstrasse 22, 64287 Darmstadt, Germany, Fax: (+49)‐6151‐166636
| | - Michael Kickstein
- Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Petersenstrasse 22, 64287 Darmstadt, Germany, Fax: (+49)‐6151‐166636
| | - Julia Metzner
- Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Petersenstrasse 22, 64287 Darmstadt, Germany, Fax: (+49)‐6151‐166636
| | - Martin Weiß
- Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Petersenstrasse 22, 64287 Darmstadt, Germany, Fax: (+49)‐6151‐166636
| | - Alan Berry
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9 JT, U.K
| | - Wolf‐Dieter Fessner
- Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Petersenstrasse 22, 64287 Darmstadt, Germany, Fax: (+49)‐6151‐166636
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27
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The use of sialidase therapy for respiratory viral infections. Antiviral Res 2013; 98:401-9. [PMID: 23602850 PMCID: PMC7172378 DOI: 10.1016/j.antiviral.2013.04.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 03/29/2013] [Accepted: 04/11/2013] [Indexed: 01/16/2023]
Abstract
DAS181 is a novel inhaled therapy for the treatment of influenza. Treatment targets sialic acid on the cell surface. The sialidase removes both α2-3 and α2-6 linked sialic acids. The use of an amphiregulin tag to the sialidase anchors it to the cell surface. Treatment for 3 days appears effective in treating influenza and parainfluenza.
DAS181 is an inhaled bacterial sialidase which functions by removing sialic acid (Sia) from the surface of epithelial cells, preventing attachment and subsequent infection by respiratory viruses that utilize Sia as a receptor. DAS181 is typical of bacterial sialidases in cleaving Sia α2-3 and Sia α2-6 linkages, and it also has a demonstrated effect against acetylated and hydroxylated forms of Sia. The potency of the compound has been enhanced by coupling the active sialidase with an amphiregulin tag, allowing a longer duration of action and minimizing spread to the systemic circulation. DAS181 is now in Phase II development for the treatment of influenza, and it has also demonstrated activity in individual cases of parainfluenza in immunosuppressed patients. Continued evaluation of the roles and activities of bacterial sialidases is required to expand the range of successful antiviral therapies targeting Sia or its derivatives.
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28
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Oroz-Guinea I, García-Junceda E. Enzyme catalysed tandem reactions. Curr Opin Chem Biol 2013; 17:236-49. [PMID: 23490810 DOI: 10.1016/j.cbpa.2013.02.015] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Revised: 01/29/2013] [Accepted: 02/14/2013] [Indexed: 01/01/2023]
Abstract
To transfer to the laboratory, the excellent efficiency shown by enzymes in Nature, biocatalysis, had to mimic several synthetic strategies used by the living organisms. Biosynthetic pathways are examples of tandem catalysis and may be assimilated in the biocatalysis field for the use of isolated multi-enzyme systems in the homogeneous phase. The concurrent action of several enzymes that work sequentially presents extraordinary advantages from the synthetic point of view, since it permits a reversible process to become irreversible, to shift the equilibrium reaction in such a way that enantiopure compounds can be obtained from prochiral or racemic substrates, reduce or eliminate problems due to product inhibition or prevent the shortage of substrates by dilution or degradation in the bulk media, etc. In this review we want to illustrate the developments of recent studies involving in vitro multi-enzyme reactions for the synthesis of different classes of organic compounds.
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Affiliation(s)
- Isabel Oroz-Guinea
- Departamento de Química Bio-Orgánica, Instituto de Química Orgánica General, CSIC, Juan de Cierva 3, 28006 Madrid, Spain.
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29
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Parker RB, McCombs JE, Kohler JJ. Sialidase specificity determined by chemoselective modification of complex sialylated glycans. ACS Chem Biol 2012; 7:1509-14. [PMID: 22704707 DOI: 10.1021/cb300241v] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Sialidases hydrolytically remove sialic acids from sialylated glycoproteins and glycolipids. Sialidases are widely distributed in nature and sialidase-mediated desialylation is implicated in normal and pathological processes. However, mechanisms by which sialidases exert their biological effects remain obscure, in part because sialidase substrate preferences are poorly defined. Here we report the design and implementation of a sialidase substrate specificity assay based on chemoselective labeling of sialosides. We show that this assay identifies components of glycosylated substrates that contribute to sialidase specificity. We demonstrate that specificity of sialidases can depend on structure of the underlying glycan, a characteristic difficult to discern using typical sialidase assays. Moreover, we discovered that Streptococcus pneumoniae sialidase NanC strongly prefers sialosides containing the Neu5Ac form of sialic acid versus those that contain Neu5Gc. We propose using this approach to evaluate sialidase preferences for diverse potential substrates.
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Affiliation(s)
- Randy B. Parker
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas
75390-9185, United States
| | - Janet E. McCombs
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas
75390-9185, United States
| | - Jennifer J. Kohler
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas
75390-9185, United States
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30
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Khedri Z, Li Y, Cao H, Qu J, Yu H, Muthana MM, Chen X. Synthesis of selective inhibitors against V. cholerae sialidase and human cytosolic sialidase NEU2. Org Biomol Chem 2012; 10:6112-20. [PMID: 22641268 PMCID: PMC11302589 DOI: 10.1039/c2ob25335f] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Sialidases or neuraminidases catalyze the hydrolysis of terminal sialic acid residues from sialyl oligosaccharides and glycoconjugates. Despite successes in developing potent inhibitors specifically against influenza virus neuraminidases, the progress in designing and synthesizing selective inhibitors against bacterial and human sialidases has been slow. Guided by sialidase substrate specificity studies and sialidase crystal structural analysis, a number of 2-deoxy-2,3-dehydro-N-acetylneuraminic acid (DANA or Neu5Ac2en) analogues with modifications at C9 or at both C5 and C9 were synthesized. Inhibition studies of various bacterial sialidases and human cytosolic sialidase NEU2 revealed that Neu5Gc9N(3)2en and Neu5AcN(3)9N(3)2en are selective inhibitors against V. cholerae sialidase and human NEU2, respectively.
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Affiliation(s)
| | | | | | - Jingyao Qu
- Department of Chemistry, University of California, One Shields Avenue, Davis, California, 95616, USA
| | - Hai Yu
- Department of Chemistry, University of California, One Shields Avenue, Davis, California, 95616, USA
| | - Musleh M. Muthana
- Department of Chemistry, University of California, One Shields Avenue, Davis, California, 95616, USA
| | - Xi Chen
- Department of Chemistry, University of California, One Shields Avenue, Davis, California, 95616, USA
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31
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Sugiarto G, Lau K, Qu J, Li Y, Lim S, Mu S, Ames JB, Fisher AJ, Chen X. A sialyltransferase mutant with decreased donor hydrolysis and reduced sialidase activities for directly sialylating LewisX. ACS Chem Biol 2012; 7:1232-40. [PMID: 22583967 DOI: 10.1021/cb300125k] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Glycosyltransferases are important catalysts for enzymatic and chemoenzymatic synthesis of complex carbohydrates and glycoconjugates. The glycosylation efficiencies of wild-type glycosyltransferases vary considerably when different acceptor substrates are used. Using a multifunctional Pasteurella multocida sialyltransferase 1 (PmST1) as an example, we show here that the sugar nucleotide donor hydrolysis activity of glycosyltransferases contributes significantly to the low yield of glycosylation when a poor acceptor substrate is used. With a protein crystal structure-based rational design, we generated a single mutant (PmST1 M144D) with decreased donor hydrolysis activity without significantly affecting its α2-3-sialylation activity when a poor fucose-containing acceptor substrate was used. The single mutant also has a drastically decreased α2-3-sialidase activity. X-ray and NMR structural studies revealed that unlike the wild-type PmST1, which changes to a closed conformation once a donor binds, the M144D mutant structure adopts an open conformation even in the presence of the donor substrate. The PmST1 M144D mutant with decreased donor hydrolysis and reduced sialidase activity has been used as a powerful catalyst for efficient chemoenzymatic synthesis of complex sialyl Lewis(x) antigens containing different sialic acid forms. This work sheds new light on the effect of donor hydrolysis activity of glycosyltransferases on glycosyltransferase-catalyzed reactions and provides a novel strategy to improve glycosyltransferase substrate promiscuity by decreasing its donor hydrolysis activity.
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Affiliation(s)
- Go Sugiarto
- Department
of Chemistry and ‡Department of Molecular and Cellular Biology, University of California-Davis, One Shields Avenue,
Davis, California 95616, United States
| | - Kam Lau
- Department
of Chemistry and ‡Department of Molecular and Cellular Biology, University of California-Davis, One Shields Avenue,
Davis, California 95616, United States
| | - Jingyao Qu
- Department
of Chemistry and ‡Department of Molecular and Cellular Biology, University of California-Davis, One Shields Avenue,
Davis, California 95616, United States
| | - Yanhong Li
- Department
of Chemistry and ‡Department of Molecular and Cellular Biology, University of California-Davis, One Shields Avenue,
Davis, California 95616, United States
| | - Sunghyuk Lim
- Department
of Chemistry and ‡Department of Molecular and Cellular Biology, University of California-Davis, One Shields Avenue,
Davis, California 95616, United States
| | - Shengmao Mu
- Department
of Chemistry and ‡Department of Molecular and Cellular Biology, University of California-Davis, One Shields Avenue,
Davis, California 95616, United States
| | - James B. Ames
- Department
of Chemistry and ‡Department of Molecular and Cellular Biology, University of California-Davis, One Shields Avenue,
Davis, California 95616, United States
| | - Andrew J. Fisher
- Department
of Chemistry and ‡Department of Molecular and Cellular Biology, University of California-Davis, One Shields Avenue,
Davis, California 95616, United States
| | - Xi Chen
- Department
of Chemistry and ‡Department of Molecular and Cellular Biology, University of California-Davis, One Shields Avenue,
Davis, California 95616, United States
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32
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Davies LRL, Pearce OMT, Tessier MB, Assar S, Smutova V, Pajunen M, Sumida M, Sato C, Kitajima K, Finne J, Gagneux P, Pshezhetsky A, Woods R, Varki A. Metabolism of vertebrate amino sugars with N-glycolyl groups: resistance of α2-8-linked N-glycolylneuraminic acid to enzymatic cleavage. J Biol Chem 2012; 287:28917-31. [PMID: 22692207 DOI: 10.1074/jbc.m112.365056] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The sialic acid (Sia) N-acetylneuraminic acid (Neu5Ac) and its hydroxylated derivative N-glycolylneuraminic acid (Neu5Gc) differ by one oxygen atom. CMP-Neu5Gc is synthesized from CMP-Neu5Ac, with Neu5Gc representing a highly variable fraction of total Sias in various tissues and among different species. The exception may be the brain, where Neu5Ac is abundant and Neu5Gc is reported to be rare. Here, we confirm this unusual pattern and its evolutionary conservation in additional samples from various species, concluding that brain Neu5Gc expression has been maintained at extremely low levels over hundreds of millions of years of vertebrate evolution. Most explanations for this pattern do not require maintaining neural Neu5Gc at such low levels. We hypothesized that resistance of α2-8-linked Neu5Gc to vertebrate sialidases is the detrimental effect requiring the relative absence of Neu5Gc from brain. This linkage is prominent in polysialic acid (polySia), a molecule with critical roles in vertebrate neural development. We show that Neu5Gc is incorporated into neural polySia and does not cause in vitro toxicity. Synthetic polymers of Neu5Ac and Neu5Gc showed that mammalian and bacterial sialidases are much less able to hydrolyze α2-8-linked Neu5Gc at the nonreducing terminus. Notably, this difference was not seen with acid-catalyzed hydrolysis of polySias. Molecular dynamics modeling indicates that differences in the three-dimensional conformation of terminal saccharides may partly explain reduced enzymatic activity. In keeping with this, polymers of N-propionylneuraminic acid are sensitive to sialidases. Resistance of Neu5Gc-containing polySia to sialidases provides a potential explanation for the rarity of Neu5Gc in the vertebrate brain.
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Affiliation(s)
- Leela R L Davies
- Department of Medicine, Glycobiology Research and Training Center, University of California San Diego, La Jolla, California 92093-0687, USA
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33
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Sialic acid metabolism and sialyltransferases: natural functions and applications. Appl Microbiol Biotechnol 2012; 94:887-905. [PMID: 22526796 DOI: 10.1007/s00253-012-4040-1] [Citation(s) in RCA: 196] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Revised: 03/16/2012] [Accepted: 03/16/2012] [Indexed: 12/17/2022]
Abstract
Sialic acids are a family of negatively charged monosaccharides which are commonly presented as the terminal residues in glycans of the glycoconjugates on eukaryotic cell surface or as components of capsular polysaccharides or lipooligosaccharides of some pathogenic bacteria. Due to their important biological and pathological functions, the biosynthesis, activation, transfer, breaking down, and recycle of sialic acids are attracting increasing attention. The understanding of the sialic acid metabolism in eukaryotes and bacteria leads to the development of metabolic engineering approaches for elucidating the important functions of sialic acid in mammalian systems and for large-scale production of sialosides using engineered bacterial cells. As the key enzymes in biosynthesis of sialylated structures, sialyltransferases have been continuously identified from various sources and characterized. Protein crystal structures of seven sialyltransferases have been reported. Wild-type sialyltransferases and their mutants have been applied with or without other sialoside biosynthetic enzymes for producing complex sialic acid-containing oligosaccharides and glycoconjugates. This mini-review focuses on current understanding and applications of sialic acid metabolism and sialyltransferases.
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34
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Khedri Z, Muthana MM, Li Y, Muthana SM, Yu H, Cao H, Chen X. Probe sialidase substrate specificity using chemoenzymatically synthesized sialosides containing C9-modified sialic acid. Chem Commun (Camb) 2012; 48:3357-9. [PMID: 22361713 DOI: 10.1039/c2cc17393j] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A library of α2-3- and α2-6-linked sialyl galactosides containing C9-modified sialic acids was synthesized from C6-modified mannose derivatives using an efficient one-pot three-enzyme system. These sialosides were used in a high-throughput sialidase substrate specificity assay to elucidate the importance of C9-OH in sialidase recognition.
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Affiliation(s)
- Zahra Khedri
- Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, USA
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35
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Abstract
Sialic acids, also known as neuraminic acids, are a family of negatively charged α-keto acids with a nine-carbon backbone. These unique sugars have been found at the termini of many glycan chains of vertebrate cell surface, which play pivotal roles in mediating or modulating a variety of physiological and pathological processes. This brief review covers general approaches for synthesizing sialic acid containing structures. Recently developed synthetic methods along with structural diversities and biological functions of sialic acid are discussed.
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Affiliation(s)
- Hongzhi Cao
- National Glycoengineering Research Center, Shandong University, Jinan, Shandong 250012, P. R. China
| | - Xi Chen
- Department of Chemistry, University of California-Davis, One Shields Avenue, CA 95616, USA
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36
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Sugiarto G, Lau K, Li Y, Khedri Z, Yu H, Le DT, Chen X. Decreasing the sialidase activity of multifunctional Pasteurella multocida α2-3-sialyltransferase 1 (PmST1) by site-directed mutagenesis. MOLECULAR BIOSYSTEMS 2011; 7:3021-7. [PMID: 21858283 PMCID: PMC11314589 DOI: 10.1039/c1mb05182b] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/11/2024]
Abstract
Pasteurella multocida α2-3-sialyltransferase 1 (PmST1) is a multifunctional enzyme which has α2-6-sialyltransferase, α2-3-sialidase, and α2-3-trans-sialidase activities in addition to its major α2-3-sialyltransferase activity. The presence of the α2-3-sialidase activity of PmST1 complicates its application in enzymatic synthesis of α2-3-linked sialosides as the product formed can be hydrolyzed by the enzyme. Herein we show that the α2-3-sialidase activity of PmST1 can be significantly decreased by protein crystal structure-based site-directed mutagenesis. A PmST1 double mutant E271F/R313Y showed a significantly (6333-fold) decreased sialidase activity without affecting its α2-3-sialyltransferase activity. The double mutant E271F/R313Y, therefore, is a superior enzyme for enzymatic synthesis of α2-3-linked sialosides.
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Affiliation(s)
- Go Sugiarto
- Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Kam Lau
- Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Yanhong Li
- Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Zahra Khedri
- Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Hai Yu
- Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Diem-Thuy Le
- Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Xi Chen
- Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA
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37
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Li Y, Yu H, Cao H, Muthana S, Chen X. Pasteurella multocida CMP-sialic acid synthetase and mutants of Neisseria meningitidis CMP-sialic acid synthetase with improved substrate promiscuity. Appl Microbiol Biotechnol 2011; 93:2411-23. [PMID: 21968653 DOI: 10.1007/s00253-011-3579-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 08/11/2011] [Accepted: 09/13/2011] [Indexed: 01/19/2023]
Abstract
Cytidine 5'-monophosphate (CMP)-sialic acid synthetases (CSSs) catalyze the formation of CMP-sialic acid from CTP and sialic acid, a key step for sialyltransferase-catalyzed biosynthesis of sialic acid-containing oligosaccharides and glycoconjugates. More than 50 different sialic acid forms have been identified in nature. To facilitate the enzymatic synthesis of sialosides with diverse naturally occurring sialic acid forms and their non-natural derivatives, CMP-sialic acid synthetases with promiscuous substrate specificity are needed. Herein we report the cloning, characterization, and substrate specificity studies of a new CSS from Pasteurella multocida strain P-1059 (PmCSS) and a CSS from Haemophillus ducreyi (HdCSS). Based on protein sequence alignment and substrate specificity studies of these two CSSs and a Neisseria meningitidis CSS (NmCSS), as well as crystal structure modeling and analysis of NmCSS, NmCSS mutants (NmCSS_S81R and NmCSS_Q163A) with improved substrate promiscuity were generated. The strategy of combining substrate specificity studies of enzymes from different sources and protein crystal structure studies can be a general approach for designing enzyme mutants with improved activity and substrate promiscuity.
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Affiliation(s)
- Yanhong Li
- Department of Chemistry, University of California-Davis, Davis, CA 95616, USA
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38
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Song X, Yu H, Chen X, Lasanajak Y, Tappert MM, Air GM, Tiwari VK, Cao H, Chokhawala HA, Zheng H, Cummings RD, Smith DF. A sialylated glycan microarray reveals novel interactions of modified sialic acids with proteins and viruses. J Biol Chem 2011; 286:31610-22. [PMID: 21757734 PMCID: PMC3173124 DOI: 10.1074/jbc.m111.274217] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Revised: 07/07/2011] [Indexed: 01/22/2023] Open
Abstract
Many glycan-binding proteins in animals and pathogens recognize sialic acid or its modified forms, but their molecular recognition is poorly understood. Here we describe studies on sialic acid recognition using a novel sialylated glycan microarray containing modified sialic acids presented on different glycan backbones. Glycans terminating in β-linked galactose at the non-reducing end and with an alkylamine-containing fluorophore at the reducing end were sialylated by a one-pot three-enzyme system to generate α2-3- and α2-6-linked sialyl glycans with 16 modified sialic acids. The resulting 77 sialyl glycans were purified and quantified, characterized by mass spectrometry, covalently printed on activated slides, and interrogated with a number of key sialic acid-binding proteins and viruses. Sialic acid recognition by the sialic acid-binding lectins Sambucus nigra agglutinin and Maackia amurensis lectin-I, which are routinely used for detecting α2-6- and α2-3-linked sialic acids, are affected by sialic acid modifications, and both lectins bind glycans terminating with 2-keto-3-deoxy-D-glycero-D-galactonononic acid (Kdn) and Kdn derivatives stronger than the derivatives of more common N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc). Three human parainfluenza viruses bind to glycans terminating with Neu5Ac or Neu5Gc and some of their derivatives but not to Kdn and its derivatives. Influenza A virus also does not bind glycans terminating in Kdn or Kdn derivatives. An especially novel aspect of human influenza A virus binding is its ability to equivalently recognize glycans terminated with either α2-6-linked Neu5Ac9Lt or α2-6-linked Neu5Ac. Our results demonstrate the utility of this sialylated glycan microarray to investigate the biological importance of modified sialic acids in protein-glycan interactions.
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Affiliation(s)
- Xuezheng Song
- From the Department of Biochemistry and the Glycomics Center, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Hai Yu
- the Department of Chemistry, University of California, Davis, California 95616, and
| | - Xi Chen
- the Department of Chemistry, University of California, Davis, California 95616, and
| | - Yi Lasanajak
- From the Department of Biochemistry and the Glycomics Center, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Mary M. Tappert
- the Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73126
| | - Gillian M. Air
- the Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73126
| | - Vinod K. Tiwari
- the Department of Chemistry, University of California, Davis, California 95616, and
| | - Hongzhi Cao
- the Department of Chemistry, University of California, Davis, California 95616, and
| | | | - Haojie Zheng
- the Department of Chemistry, University of California, Davis, California 95616, and
| | - Richard D. Cummings
- From the Department of Biochemistry and the Glycomics Center, Emory University School of Medicine, Atlanta, Georgia 30322
| | - David F. Smith
- From the Department of Biochemistry and the Glycomics Center, Emory University School of Medicine, Atlanta, Georgia 30322
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39
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Flexibility of Substrate Binding of Cytosine-5′-Monophosphate-N-Acetylneuraminate Synthetase (CMP-Sialate Synthetase) from Neisseria meningitidis: An Enabling Catalyst for the Synthesis of Neo-sialoconjugates. Adv Synth Catal 2011. [DOI: 10.1002/adsc.201100412] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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40
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Ricca E, Brucher B, Schrittwieser JH. Multi-Enzymatic Cascade Reactions: Overview and Perspectives. Adv Synth Catal 2011. [DOI: 10.1002/adsc.201100256] [Citation(s) in RCA: 374] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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41
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42
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Li Y, Yu H, Chen Y, Lau K, Cai L, Cao H, Tiwari VK, Qu J, Thon V, Wang PG, Chen X. Substrate promiscuity of N-acetylhexosamine 1-kinases. Molecules 2011; 16:6396-407. [PMID: 21799473 PMCID: PMC6264712 DOI: 10.3390/molecules16086396] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Revised: 07/22/2011] [Accepted: 07/25/2011] [Indexed: 11/16/2022] Open
Abstract
N-Acetylhexosamine 1-kinase (NahK) catalyzes the direct addition of a phosphate from adenosine 5'-triphosphate (ATP) to the anomeric position of N-acetylhexosamine and shows similar activity towards N-acetylglucosamine (GlcNAc) and N-acetylgalactosamine (GalNAc). Herein we report the cloning, characterization, and substrate specificity studies of two NahKs from Bifidobacterium infantis ATCC15697 and Bifidobacterium longum ATCC55813, respectively. A new capillary electrophoresis assay method has been developed for enzyme activity assays. Both enzymes have a good expression level in E. coli (180-185 mg/L culture) and can tolerate diverse modifications at C2 of GlcNAc and GalNAc. Various GlcNAc derivatives with C6, both C2 and C6, as well as both C2 and C3 modifications are tolerable substrates for the newly cloned NahKs. Quite interestingly, despite of their low activities toward glucose and galactose, the activities of both NahKs are much higher for mannose and some of its C2, C4, and C6 derivatives. These NahKs are excellent catalysts for enzymatic and chemoenzymatic synthesis of carbohydrates.
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Affiliation(s)
- Yanhong Li
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA; (Y.L.); (H.Y.); (Y.C.); (K.L.); (J.Q.); (V.T.)
| | - Hai Yu
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA; (Y.L.); (H.Y.); (Y.C.); (K.L.); (J.Q.); (V.T.)
| | - Yi Chen
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA; (Y.L.); (H.Y.); (Y.C.); (K.L.); (J.Q.); (V.T.)
| | - Kam Lau
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA; (Y.L.); (H.Y.); (Y.C.); (K.L.); (J.Q.); (V.T.)
| | - Li Cai
- Departments of Biochemistry and Chemistry, Ohio State University, Columbus, OH 43210, USA; (L.C.); (P.G.W.)
| | - Hongzhi Cao
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA; (Y.L.); (H.Y.); (Y.C.); (K.L.); (J.Q.); (V.T.)
| | - Vinod Kumar Tiwari
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA; (Y.L.); (H.Y.); (Y.C.); (K.L.); (J.Q.); (V.T.)
| | - Jingyao Qu
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA; (Y.L.); (H.Y.); (Y.C.); (K.L.); (J.Q.); (V.T.)
| | - Vireak Thon
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA; (Y.L.); (H.Y.); (Y.C.); (K.L.); (J.Q.); (V.T.)
| | - Peng George Wang
- Departments of Biochemistry and Chemistry, Ohio State University, Columbus, OH 43210, USA; (L.C.); (P.G.W.)
| | - Xi Chen
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA; (Y.L.); (H.Y.); (Y.C.); (K.L.); (J.Q.); (V.T.)
- Author to whom correspondence should be addressed; ; Tel.: +1-530-754-6037; Fax: +1-530-752-8995
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Kajihara Y, Nishigaki S, Hanzawa D, Nakanishi G, Okamoto R, Yamamoto N. Unique self-anhydride formation in the degradation of cytidine-5'-monophosphosialic acid (CMP-Neu5Ac) and cytidine-5'-diphosphosialic acid (CDP-Neu5Ac) and its application in CMP-sialic acid analogue synthesis. Chemistry 2011; 17:7645-55. [PMID: 21598321 DOI: 10.1002/chem.201003387] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2010] [Indexed: 01/08/2023]
Abstract
Sialyloligosaccharides are synthesised by various glycosyltransferases and sugar nucleotides. All of these nucleotides are diphosphate compounds except for cytidine-5'-monophosphosialic acid (CMP-Neu5Ac). To obtain an insight into why cytidine-5'-diphosphosialic acid (CDP-Neu5Ac) has not been used for the sialyltransferase reaction and why it is not found in biological organisms, the compound was synthesised. This synthesis provided the interesting finding that the carboxylic acid moiety of the sialic acid attacks the attached phosphate group. This interaction yields an activated anhydride between carboxylic acid and the phosphate group and leads to hydrolysis of the pyrophosphate linkage. The mechanism was demonstrated by stable isotope-labelling experiments. This finding suggested that CMP-Neu5Ac might also form the corresponding anhydride structure between carboxylic acid and phosphate, and this seems to be the reason why CMP-Neu5Ac is acid labile in relation to other sugar nucleotides. To confirm the role of the carboxylic acid, CMP-Neu5Ac derivatives in which the carboxylic acid moiety in the sialic acid was substituted with amide or ester groups were synthesised. These analogues clearly exhibited resistance to acid hydrolysis. This result indicated that the carboxylic acid of Neu5Ac is associated with its stability in solution. This finding also enabled the development of a novel chemical synthetic method for CMP-Neu5Ac and CMP-sialic acid derivatives.
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Affiliation(s)
- Yasuhiro Kajihara
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka 560-0043, Japan.
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Li Y, Cao H, Dao N, Luo Z, Yu H, Chen Y, Xing Z, Baumgarth N, Cardona C, Chen X. High-throughput neuraminidase substrate specificity study of human and avian influenza A viruses. Virology 2011; 415:12-9. [PMID: 21501853 DOI: 10.1016/j.virol.2011.03.024] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2011] [Revised: 01/31/2011] [Accepted: 03/21/2011] [Indexed: 12/12/2022]
Abstract
Despite the importance of neuraminidase (NA) activity in effective infection by influenza A viruses, limited information exists about the differences of substrate preferences of viral neuraminidases from different hosts or from different strains. Using a high-throughput screening format and a library of twenty α2-3- or α2-6-linked para-nitrophenol-tagged sialylgalactosides, substrate specificity of NAs on thirty-seven strains of human and avian influenza A viruses was studied using intact viral particles. Neuraminidases of all viruses tested cleaved both α2-3- and α2-6-linked sialosides but preferred α2-3-linked ones and the activity was dependent on the terminal sialic acid structure. In contrast to NAs of other subtypes of influenza A viruses which did not cleave 2-keto-3-deoxy-d-glycero-d-galacto-nonulosonic acid (Kdn) or 5-deoxy Kdn (5d-Kdn), NAs of all N7 subtype viruses tested had noticeable hydrolytic activities on α2-3-linked sialosides containing Kdn or 5d-Kdn. Additionally, group 1 NAs showed efficient activity in cleaving N-azidoacetylneuraminic acid from α2-3-linked sialoside.
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Affiliation(s)
- Yanhong Li
- Department of Chemistry, University of California, Davis, CA 95616, USA
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Sela DA, Li Y, Lerno L, Wu S, Marcobal AM, German JB, Chen X, Lebrilla CB, Mills DA. An infant-associated bacterial commensal utilizes breast milk sialyloligosaccharides. J Biol Chem 2011; 286:11909-18. [PMID: 21288901 DOI: 10.1074/jbc.m110.193359] [Citation(s) in RCA: 138] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Lactating mothers secrete milk sialyloligosaccharides (MSOs) that function as anti-adhesives once provided to the neonate. Particular infant-associated commensals, such as Bifidobacterium longum subsp. infantis, consume neutral milk oligosaccharides, although their ability to utilize acidic oligosaccharides has not been assessed. Temporal glycoprofiling of acidic HMO consumed during fermentation demonstrated a single composition, with several isomers, corresponding to sialylated lacto-N-tetraose. To utilize MSO, B. longum subsp. infantis deploys a sialidase that cleaves α2-6 and α2-3 linkages. NanH2, encoded within the HMO catabolic cluster is up-regulated during HMO fermentation and is active on sialylated lacto-N-tetraose. These results demonstrate that commensal microorganisms do utilize MSO, a substrate that may be enriched in the distal gastrointestinal tract.
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Affiliation(s)
- David A Sela
- Microbiology Graduate Group, Department of Chemistry, The Robert Mondavi Institute, University of California Davis, Davis, CA 95616-5270, USA
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Li Y, Cao H, Yu H, Chen Y, Lau K, Qu J, Thon V, Sugiarto G, Chen X. Identifying selective inhibitors against the human cytosolic sialidase NEU2 by substrate specificity studies. MOLECULAR BIOSYSTEMS 2011; 7:1060-72. [PMID: 21206954 DOI: 10.1039/c0mb00244e] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Aberrant expression of human sialidases has been shown to associate with various pathological conditions. Despite the effort in the sialidase inhibitor design, less attention has been paid to designing specific inhibitors against human sialidases and characterizing the substrate specificity of different sialidases regarding diverse terminal sialic acid forms and sialyl linkages. This is mainly due to the lack of sialoside probes and efficient screening methods, as well as limited access to human sialidases. A low cellular expression level of the human sialidase NEU2 hampers its functional and inhibitory studies. Here we report the successful cloning and expression of the human sialidase NEU2 in E. coli. About 11 mg of soluble active NEU2 was routinely obtained from 1 L of E. coli cell culture. Substrate specificity studies of the recombinant human NEU2 using twenty p-nitrophenol (pNP)-tagged α2-3- or α2-6-linked sialyl galactosides containing different terminal sialic acid forms including common N-acetylneuraminic acid (Neu5Ac), non-human N-glycolylneuraminic acid (Neu5Gc), 2-keto-3-deoxy-D-glycero-D-galacto-nonulosonic acid (Kdn), or their C5-derivatives in a microtiter plate-based high-throughput colorimetric assay identified a unique structural feature specifically recognized by the human NEU2 but not two bacterial sialidases. The results obtained from substrate specificity studies were used to guide the design of a sialidase inhibitor that was selective against human NEU2. The selectivity of the inhibitor was revealed by the comparison of sialidase crystal structures and inhibitor docking studies.
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Affiliation(s)
- Yanhong Li
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA.
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