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Mishra B, Yuan Y, Yu H, Kang H, Gao J, Daniels R, Chen X. Synthetic Sialosides Terminated with 8-N-Substituted Sialic Acid as Selective Substrates for Sialidases from Bacteria and Influenza Viruses. Angew Chem Int Ed Engl 2024; 63:e202403133. [PMID: 38713874 DOI: 10.1002/anie.202403133] [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: 02/16/2024] [Revised: 04/17/2024] [Accepted: 05/02/2024] [Indexed: 05/09/2024]
Abstract
Sialosides containing C8-modified sialic acids are challenging synthetic targets but potentially useful probes for diagnostic substrate profiling of sialidases and elucidating the binding specificity of sialic acid-interacting proteins. Here, we demonstrate efficient chemoenzymatic methods for synthesizing para-nitrophenol-tagged α2-3- and α2-6-linked sialyl galactosides containing C8-acetamido, C8-azido, or C8-amino derivatized N-acetylneuraminic acid (Neu5Ac). High-throughput substrate specificity studies showed that the C8-modification of sialic acid significantly changes its recognition by sialidases from humans, various bacteria, and different influenza A and B viruses. Sialosides carrying Neu5Ac with a C8-azido modification were generally well tolerated by all the sialidases we tested, whereas sialosides containing C8-acetamido-modified Neu5Ac were only cleaved by selective bacterial sialidases. In contrast, sialosides with C8-amino-modified Neu5Ac were cleaved by a combination of selective bacterial and influenza A virus sialidases. These results indicate that sialosides terminated with a C8-amino or C8-acetamido-modified sialic acid can be used with other sialosides for diagnostic profiling of disease-causing sialidase-producing pathogens.
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Affiliation(s)
- Bijoyananda Mishra
- Department of Chemistry, University of California, One Shields Avenue, Davis, California, 95616, United States
| | - Yue Yuan
- 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
| | - Hyeog Kang
- Division of Viral Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, 20993, United States
| | - Jin Gao
- Division of Viral Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, 20993, United States
| | - Robert Daniels
- Division of Viral Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, 20993, United States
| | - Xi Chen
- Department of Chemistry, University of California, One Shields Avenue, Davis, California, 95616, United States
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2
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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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3
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Kooner A, Yuan Y, Yu H, Kang H, Klenow L, Daniels R, Chen X. Sialosides Containing 7- N-Acetyl Sialic Acid Are Selective Substrates for Neuraminidases from Influenza A Viruses. ACS Infect Dis 2022; 9:33-41. [PMID: 36455156 PMCID: PMC9840695 DOI: 10.1021/acsinfecdis.2c00502] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Sialidases or neuraminidases are sialic-acid-cleaving enzymes that are expressed by a broad spectrum of organisms, including pathogens. In nature, sialic acids are monosaccharides with diverse structural variations, but the lack of novel probes has made it difficult to determine how sialic acid modifications impact the recognition by sialidases. Here, we used a chemoenzymatic synthon strategy to generate a set of α2-3- and α2-6-linked sialoside probes that contain 7-N-acetyl or 7,9-di-N-acetyl sialic acid as structure mimics for those containing the less stable naturally occurring 7-O-acetyl- or 7,9-di-O-acetyl modifications. These probes were used to compare the substrate specificity of several sialidases from different origins. Our results show that 7-N-acetyl sialic acid was readily cleaved by neuraminidases from H1N1 and H3N2 influenza A viruses, but not by sialidases of human or bacterial origin, thereby indicating that the influenza enzymes possess a distinctive and more promiscuous substrate binding pocket.
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Affiliation(s)
- Anoopjit
Singh Kooner
- Department
of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States
| | - Yue Yuan
- 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
| | - Hyeog Kang
- Division
of Viral Products, Center for Biologics
Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993, United States
| | - Laura Klenow
- Division
of Viral Products, Center for Biologics
Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993, United States
| | - Robert Daniels
- Division
of Viral Products, Center for Biologics
Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993, United States
| | - Xi Chen
- Department
of Chemistry, University of California, One Shields Avenue, Davis, California 95616, United States,
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4
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Escopy S, Singh Y, Stine KJ, Demchenko AV. HPLC‐Based Automated Synthesis of Glycans in Solution. Chemistry 2022; 28:e202201180. [DOI: 10.1002/chem.202201180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Indexed: 11/09/2022]
Affiliation(s)
- Samira Escopy
- Department of Chemistry and Biochemistry University of Missouri - St. Louis One University Boulevard St. Louis Missouri 63121 USA
- Department of Chemistry Saint Louis University 3501 Laclede Ave St. Louis Missouri 63103 USA
| | - Yashapal Singh
- Department of Chemistry and Biochemistry University of Missouri - St. Louis One University Boulevard St. Louis Missouri 63121 USA
| | - Keith J. Stine
- Department of Chemistry and Biochemistry University of Missouri - St. Louis One University Boulevard St. Louis Missouri 63121 USA
| | - Alexei V. Demchenko
- Department of Chemistry and Biochemistry University of Missouri - St. Louis One University Boulevard St. Louis Missouri 63121 USA
- Department of Chemistry Saint Louis University 3501 Laclede Ave St. Louis Missouri 63103 USA
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5
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Zhang L, Yu H, Bai Y, Mishra B, Yang X, Wang J, Yu EB, Li R, Chen X. A Neoglycoprotein-Immobilized Fluorescent Magnetic Bead Suspension Multiplex Array for Galectin-Binding Studies. Molecules 2021; 26:6194. [PMID: 34684775 PMCID: PMC8541226 DOI: 10.3390/molecules26206194] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/07/2021] [Accepted: 10/09/2021] [Indexed: 11/16/2022] Open
Abstract
Carbohydrate-protein conjugates have diverse applications. They have been used clinically as vaccines against bacterial infection and have been developed for high-throughput assays to elucidate the ligand specificities of glycan-binding proteins (GBPs) and antibodies. Here, we report an effective process that combines highly efficient chemoenzymatic synthesis of carbohydrates, production of carbohydrate-bovine serum albumin (glycan-BSA) conjugates using a squarate linker, and convenient immobilization of the resulting neoglycoproteins on carboxylate-coated fluorescent magnetic beads for the development of a suspension multiplex array platform. A glycan-BSA-bead array containing BSA and 50 glycan-BSA conjugates with tuned glycan valency was generated. The binding profiles of six plant lectins with binding preference towards Gal and/or GalNAc, as well as human galectin-3 and galectin-8, were readily obtained. Our results provide useful information to understand the multivalent glycan-binding properties of human galectins. The neoglycoprotein-immobilized fluorescent magnetic bead suspension multiplex array is a robust and flexible platform for rapid analysis of glycan and GBP interactions and will find broad applications.
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Affiliation(s)
- Libo Zhang
- Department of Chemistry, University of California, Davis, CA 95616, USA; (L.Z.); (H.Y.); (Y.B.); (B.M.); (X.Y.); (J.W.); (E.B.Y.); (R.L.)
| | - Hai Yu
- Department of Chemistry, University of California, Davis, CA 95616, USA; (L.Z.); (H.Y.); (Y.B.); (B.M.); (X.Y.); (J.W.); (E.B.Y.); (R.L.)
| | - Yuanyuan Bai
- Department of Chemistry, University of California, Davis, CA 95616, USA; (L.Z.); (H.Y.); (Y.B.); (B.M.); (X.Y.); (J.W.); (E.B.Y.); (R.L.)
| | - Bijoyananda Mishra
- Department of Chemistry, University of California, Davis, CA 95616, USA; (L.Z.); (H.Y.); (Y.B.); (B.M.); (X.Y.); (J.W.); (E.B.Y.); (R.L.)
| | - Xiaoxiao Yang
- Department of Chemistry, University of California, Davis, CA 95616, USA; (L.Z.); (H.Y.); (Y.B.); (B.M.); (X.Y.); (J.W.); (E.B.Y.); (R.L.)
| | - Jing Wang
- Department of Chemistry, University of California, Davis, CA 95616, USA; (L.Z.); (H.Y.); (Y.B.); (B.M.); (X.Y.); (J.W.); (E.B.Y.); (R.L.)
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Evan B. Yu
- Department of Chemistry, University of California, Davis, CA 95616, USA; (L.Z.); (H.Y.); (Y.B.); (B.M.); (X.Y.); (J.W.); (E.B.Y.); (R.L.)
| | - Riyao Li
- Department of Chemistry, University of California, Davis, CA 95616, USA; (L.Z.); (H.Y.); (Y.B.); (B.M.); (X.Y.); (J.W.); (E.B.Y.); (R.L.)
| | - Xi Chen
- Department of Chemistry, University of California, Davis, CA 95616, USA; (L.Z.); (H.Y.); (Y.B.); (B.M.); (X.Y.); (J.W.); (E.B.Y.); (R.L.)
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6
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Gao H, Qin Y, Zeng J, Yang Q, Jia T. Dietary intervention with sialylated lactulose affects the immunomodulatory activities of mice. J Dairy Sci 2021; 104:9494-9504. [PMID: 34176623 DOI: 10.3168/jds.2021-20327] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 05/12/2021] [Indexed: 11/19/2022]
Abstract
Four sialylated lactuloses [N-acetylneuraminic acid-α2,3-lactulose (Neu5Acα2,3lactulose), N-acetylneuraminic acid-α2,6-lactulose (Neu5Acα2,6lactulose), deaminoneuraminc acid-α2,3-lactulose (Kdnα2,3lactulose), and deaminoneuraminc acid-α-2,6-lactulose (Kdnα2,6lactulose)] were reported to modulate the immunity of mice. The influences of cytokine expression, cell immunity, humoral immunity, and nonspecific immunity were investigated in our study using several techniques. Analysis via ELISA showed that cytokine expression was induced by sialylated lactulose treatment consistently in the serum and spleen. Among the 4 tested sialylated lactuloses, Neu5Acα2,6lactulose performed the best, simultaneously and appropriately promoting the expression of proinflammatory and anti-inflammatory factors in the serum and spleen. Kdnα2,3lactulose showed the best antioxidant activity according to detection of the activity of superoxide dismutase, myeloperoxidase, peroxidase, and alkaline phosphatase. Flow cytometry revealed that only Kdnα2,3lactulose significantly boosted the CD3+ T lymphocyte ratio similarly to that of lactulose. Analysis of the hemolysin content to characterize humoral immunity revealed that Kdnα2,3lactulose notably increased hemolysin content compared with that in the control group. To evaluate the nonspecific immune effects of the 4 sialylated lactuloses, a fluorescence microsphere phagocytosis assay was used to analyze the phagocytosis of macrophages. Kdnα2,3lactulose still performed the best in enhancing the phagocytosis of macrophages, showing markedly increased phagocytic percentage and phagocytic index values compared with those in the control and lactulose groups. Comparing the differences of these 4 sialylated lactuloses in affecting immunity in mice revealed that Kdnα2,3lactulose had the best overall performance in influencing cytokine expression, cell immunity, humoral immunity, and nonspecific immunity. This study provides critical support for use of sialylated lactuloses as potential immunomodulators in foods.
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Affiliation(s)
- Haiyan Gao
- School of Food Science, Henan Institute of Science and Technology, Xinxiang 453003, China.
| | - Yueqi Qin
- School of Food Science, Henan Institute of Science and Technology, Xinxiang 453003, China
| | - Jie Zeng
- School of Food Science, Henan Institute of Science and Technology, Xinxiang 453003, China
| | - Qing Yang
- Key Laboratory for Deep Processing of Major Grain and Oil of Ministry of Education, Wuhan Polytechnic University, Wuhan 430023, China.
| | - Tian Jia
- School of Food Science, Henan Institute of Science and Technology, Xinxiang 453003, China
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7
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Li Z, Lang Y, Liu L, Bunyatov MI, Sarmiento AI, de Groot RJ, Boons GJ. Synthetic O-acetylated sialosides facilitate functional receptor identification for human respiratory viruses. Nat Chem 2021; 13:496-503. [PMID: 33753916 DOI: 10.1038/s41557-021-00655-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 02/08/2021] [Indexed: 01/31/2023]
Abstract
The transmission of viruses from animal reservoirs to humans poses major threats to public health. Preparedness for future zoonotic outbreaks requires a fundamental understanding of how viruses of animal origin have adapted to binding to a cell surface component and/or receptor of the new host. Here we report on the specificities of human and animal viruses that engage with O-acetylated sialic acid, which include betacoronaviruses, toroviruses and influenza C and D viruses. Key to these studies was the development of a chemoenzymatic methodology that can provide almost any sialate-acetylation pattern. A collection of O-acetylated sialoglycans was printed as a microarray for the determination of receptor specificity. These studies showed host-specific patterns of receptor recognition and revealed that three distinct human respiratory viruses uniquely bind 9-O-acetylated α2,8-linked disialoside. Immunofluorescence and cell entry studies support that such a glycotope as part of a ganglioside is a functional receptor for human coronaviruses.
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Affiliation(s)
- Zeshi Li
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands
| | - Yifei Lang
- Virology Division, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Lin Liu
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
| | - Mehman I Bunyatov
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands
| | - Angelic Isaza Sarmiento
- Virology Division, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Raoul J de Groot
- Virology Division, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
| | - Geert-Jan Boons
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands. .,Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA. .,Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, The Netherlands. .,Chemistry Department, University of Georgia, Athens, GA, USA.
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8
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Li R, Kooner AS, Muthana SM, Yuan Y, Yu H, Chen X. A Chemoenzymatic Synthon Strategy for Synthesizing N-Acetyl Analogues of O-Acetylated N. meningitidis W Capsular Polysaccharide Oligosaccharides. J Org Chem 2020; 85:16157-16165. [PMID: 33164526 DOI: 10.1021/acs.joc.0c02134] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
O-Acetylated sialic acid has been found in the Neisseria meningitidis serogroup W (NmW) capsular polysaccharide (CPS) and is a required structural component of clinically used NmW CPS-based polysaccharide and polysaccharide-conjugate vaccines. The role of sialic acid O-acetylation in NmW CPS, however, is not clearly understood. This is partially due to the lack of a precise control of the percentage and the location of O-acetylation which is labile and susceptible to migration. We explore chemoenzymatic synthetic strategies for preparing N-acetylated analogues of O-acetylated NmW CPS oligosaccharides which can serve as structurally stable probe mimics. Substrate specificity studies of NmW CPS polymerase (NmSiaDW) identified 4-azido-4-deoxy-N-acetylmannosamine (ManNAc4N3) and 6-azido-6-deoxy-N-acetylmannosamine (ManNAc6N3) as suitable chemoenzymatic synthons for synthesizing N-acetyl analogues of NmW CPS oligosaccharides containing 7-O-acetyl-N-acetylneuraminic acid (Neu5,7Ac2) and/or 9-O-acetyl-N-acetylneuraminic acid (Neu5,9Ac2). The synthesis was achieved by NmSiaDW-dependent sequential one-pot multienzyme (OPME) strategy with in situ generation of the corresponding sugar nucleotides from simple monosaccharides or derivatives to form N3-oligosaccharides which were converted to the desired NAc-oligosaccharides by an efficient one-step chemical transformation.
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Affiliation(s)
- Riyao Li
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
| | - Anoopjit S Kooner
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
| | - Saddam M Muthana
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States.,Department of Chemistry, Alfaisal University, Riyadh 11533, Kingdom of Saudi Arabia
| | - Yue Yuan
- 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
| | - Xi Chen
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
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9
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Nguyen T, Lee S, Yang YA, Ahn C, Sim JH, Kei TG, Barnard KN, Yu H, Millano SK, Chen X, Parrish CR, Song J. The role of 9-O-acetylated glycan receptor moieties in the typhoid toxin binding and intoxication. PLoS Pathog 2020; 16:e1008336. [PMID: 32084237 PMCID: PMC7055914 DOI: 10.1371/journal.ppat.1008336] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 03/04/2020] [Accepted: 01/20/2020] [Indexed: 12/20/2022] Open
Abstract
Typhoid toxin is an A2B5 toxin secreted from Salmonella Typhi-infected cells during human infection and is suggested to contribute to typhoid disease progression and the establishment of chronic infection. To deliver the enzymatic 'A' subunits of the toxin to the site of action in host cells, the receptor-binding 'B' subunit PltB binds to the trisaccharide glycan receptor moieties terminated in N-acetylneuraminic acid (Neu5Ac) that is α2-3 or α2-6 linked to the underlying disaccharide, galactose (Gal) and N-acetylglucosamine (GlcNAc). Neu5Ac is present in both unmodified and modified forms, with 9-O-acetylated Neu5Ac being the most common modification in humans. Here we show that host cells associated with typhoid toxin-mediated clinical signs express both unmodified and 9-O-acetylated glycan receptor moieties. We found that PltB binds to 9-O-acetylated α2-3 glycan receptor moieties with a markedly increased affinity, while the binding affinity to 9-O-acetylated α2-6 glycans is only slightly higher, as compared to the affinities of PltB to the unmodified counterparts, respectively. We also present X-ray co-crystal structures of PltB bound to related glycan moieties, which supports the different effects of 9-O-acetylated α2-3 and α2-6 glycan receptor moieties on the toxin binding. Lastly, we demonstrate that the cells exclusively expressing unmodified glycan receptor moieties are less susceptible to typhoid toxin than the cells expressing 9-O-acetylated counterparts, although typhoid toxin intoxicates both cells. These results reveal a fine-tuning mechanism of a bacterial toxin that exploits specific chemical modifications of its glycan receptor moieties for virulence and provide useful insights into the development of therapeutics against typhoid fever.
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Affiliation(s)
- Tri Nguyen
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
| | - Sohyoung Lee
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
| | - Yi-An Yang
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
| | - Changhwan Ahn
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
| | - Ji Hyun Sim
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
| | - Tiffany G. Kei
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
| | - Karen N. Barnard
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
| | - Hai Yu
- Department of Chemistry, University of California, Davis, California, United States of America
| | - Shawn K. Millano
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
| | - Xi Chen
- Department of Chemistry, University of California, Davis, California, United States of America
| | - Colin R. Parrish
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
| | - Jeongmin Song
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, New York, United States of America
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10
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Post-Glycosylation Modification of Sialic Acid and Its Role in Virus Pathogenesis. Vaccines (Basel) 2019; 7:vaccines7040171. [PMID: 31683930 PMCID: PMC6963189 DOI: 10.3390/vaccines7040171] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 10/08/2019] [Accepted: 10/23/2019] [Indexed: 01/20/2023] Open
Abstract
Sialic acids are a family of nine carbon keto-aldononulosonic acids presented at the terminal ends of glycans on cellular membranes. α-Linked sialoglycoconjugates often undergo post-glycosylation modifications, among which O-acetylation of N-acetyl neuraminic acid (Neu5Ac) is the most common in mammalian cells. Isoforms of sialic acid are critical determinants of virus pathogenesis. To date, the focus of viral receptor-mediated attachment has been on Neu5Ac. O-Acetylated Neu5Acs have been largely ignored as receptor determinants of virus pathogenesis, although it is ubiquitous across species. Significantly, the array of structures resulting from site-specific O-acetylation by sialic acid O-acetyltransferases (SOATs) provides a means to examine specificity of viral binding to host cells. Specifically, C4 O-acetylated Neu5Ac can influence virus pathogenicity. However, the biological implications of only O-acetylated Neu5Ac at C7-9 have been explored extensively. This review will highlight the biological significance, extraction methods, and synthetic modifications of C4 O-acetylated Neu5Ac that may provide value in therapeutic developments and targets to prevent virus related diseases.
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11
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Bandara MD, Stine KJ, Demchenko AV. The chemical synthesis of human milk oligosaccharides: Lacto-N-neotetraose (Galβ1→4GlcNAcβ1→3Galβ1→4Glc). Carbohydr Res 2019; 483:107743. [PMID: 31319351 PMCID: PMC6717531 DOI: 10.1016/j.carres.2019.107743] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 07/09/2019] [Accepted: 07/10/2019] [Indexed: 12/22/2022]
Abstract
The discovery of innovative methods that offer new capabilities for obtaining individual oligosaccharides from human milk will help to improve understanding their roles and boost practical applications. The total chemical synthesis of lacto-N-neotetraose (LNnT) has been completed using both linear and convergent strategies. The donor and acceptor protecting and leaving group combinations were found to be of paramount significance to successful couplings.
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Affiliation(s)
- Mithila D Bandara
- Department of Chemistry and Biochemistry, University of Missouri - St. Louis, One University Boulevard, St. Louis, Missouri, 63121, USA
| | - Keith J Stine
- Department of Chemistry and Biochemistry, University of Missouri - St. Louis, One University Boulevard, St. Louis, Missouri, 63121, USA
| | - Alexei V Demchenko
- Department of Chemistry and Biochemistry, University of Missouri - St. Louis, One University Boulevard, St. Louis, Missouri, 63121, USA.
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12
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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: 36] [Impact Index Per Article: 7.2] [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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Zeng J, Song M, Jia T, Gao H, Zhang R, Jiang J. Immunomodulatory influences of sialylated lactuloses in mice. Biochem Biophys Res Commun 2019; 514:351-357. [PMID: 31040021 DOI: 10.1016/j.bbrc.2019.04.157] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Accepted: 04/23/2019] [Indexed: 12/01/2022]
Abstract
The aim of this study was to investigate the immune modulatory influences of sialylated lactuloses in mice. The effects of the four sialylated lactuloses by gavage methods on the weight gain rate, organ, serum and spleen immunoglobulin of mice were investigated. Neu5Ac-α2,3-lactulose group and Kdn-α2,3-lactulose group had significantly higher weight gain rate than control group. The weight gain rate, thymus index and spleen index of Kdn-α2,3-lactulose group were significantly higher than control group and lactulose group. Liver and small intestine of Neu5Ac-α2,3-lactulose group, Neu5Ac-α2,6-lactulose group and Kdn-α2,6-lactulose group showed different degree of damage. IgG levels of serum and spleen in Neu5Ac-α2,6-lactulose group and Kdn-α2,6-lactulose group were significantly higher than control group and lactulose group. The contents of IgG in serum and spleen of Kdn-α2,3-lactulose group were significantly lower than that of control group, while the contents of IgA and IgM in serum were significantly higher than those of control group. The IgA level increased by 12.23% and 58.77% comparing with lactulose group and control group, respectively. The IgM level in serum of Kdn-α2,3-lactulose group mice increased by 43.88% and 8.05% comparing with control group and lactulose group, respectively. The IgA level and IgM level in spleen of Kdn-α2,3-lactulose group mice increased by 49.05% and 47.25% comparing with control group. In short, Kdn-α2,3-lactulose is relatively safe and superior to use as a food supplement or potential drug candidate. Our results also indicate that some other sialylated oligosaccharides are potentially harmful to organisms, they may cause some side effects.
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Affiliation(s)
- Jie Zeng
- School of Food Science, Henan Institute of Science and Technology, Xinxiang, 453003, China.
| | - Mengdi Song
- School of Food Science, Henan Institute of Science and Technology, Xinxiang, 453003, China
| | - Tian Jia
- School of Food Science, Henan Institute of Science and Technology, Xinxiang, 453003, China
| | - Haiyan Gao
- School of Food Science, Henan Institute of Science and Technology, Xinxiang, 453003, China
| | - Ruiyao Zhang
- School of Food Science, Henan Institute of Science and Technology, Xinxiang, 453003, China
| | - Jikai Jiang
- School of Food Science, Henan Institute of Science and Technology, Xinxiang, 453003, China
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Zhang Q, Wang Y, Zheng Q, Li J. Analysis of O-Acetylated Sialic Acids in Dried Blood Spots. Anal Chem 2019; 91:2744-2751. [DOI: 10.1021/acs.analchem.8b04420] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Qiwei Zhang
- Key Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education, Institute for Interdisciplinary Research,
Institute of Environment and Health, Jianghan University, Wuhan 430056, China
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085, China
| | - Yawei Wang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085, China
| | - Qi Zheng
- Key Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education, Institute for Interdisciplinary Research,
Institute of Environment and Health, Jianghan University, Wuhan 430056, China
| | - Jianjun Li
- National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario, Canada K1A 0R6
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Li W, McArthur JB, Chen X. Strategies for chemoenzymatic synthesis of carbohydrates. Carbohydr Res 2018; 472:86-97. [PMID: 30529493 DOI: 10.1016/j.carres.2018.11.014] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 11/22/2018] [Accepted: 11/23/2018] [Indexed: 12/30/2022]
Abstract
Carbohydrates are structurally complex but functionally important biomolecules. Therefore, they have been challenging but attractive synthetic targets. While substantial progress has been made on advancing chemical glycosylation methods, incorporating enzymes into carbohydrate synthetic schemes has become increasingly practical as more carbohydrate biosynthetic and metabolic enzymes as well as their mutants with synthetic application are identified and expressed for preparative and large-scale synthesis. Chemoenzymatic strategies that integrate the flexibility of chemical derivatization with enzyme-catalyzed reactions have been extremely powerful. Briefly summarized here are our experiences on developing one-pot multienzyme (OPME) systems and representative chemoenzymatic strategies from others using glycosyltransferase-catalyzed reactions for synthesizing diverse structures of oligosaccharides, polysaccharides, and glycoconjugates. These strategies allow the synthesis of complex carbohydrates including those containing naturally occurring carbohydrate postglycosylational modifications (PGMs) and non-natural functional groups. By combining these srategies with facile purification schemes, synthetic access to the diverse space of carbohydrate structures can be automated and will not be limited to specialists.
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Affiliation(s)
- Wanqing Li
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA, 95616, USA
| | - John B McArthur
- 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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Hunter CD, Guo T, Daskhan G, Richards MR, Cairo CW. Synthetic Strategies for Modified Glycosphingolipids and Their Design as Probes. Chem Rev 2018; 118:8188-8241. [DOI: 10.1021/acs.chemrev.8b00070] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Carmanah D. Hunter
- Alberta Glycomics Centre, Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Tianlin Guo
- Alberta Glycomics Centre, Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Gour Daskhan
- Alberta Glycomics Centre, Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Michele R. Richards
- Alberta Glycomics Centre, Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Christopher W. Cairo
- Alberta Glycomics Centre, Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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Zeng J, Hu Y, Jia T, Zhang R, Su T, Sun J, Gao H, Li G, Cao M, Song M. Chemoenzymatic synthesis of sialylated lactuloses and their inhibitory effects on Staphylococcus aureus. PLoS One 2018; 13:e0199334. [PMID: 29924858 PMCID: PMC6010273 DOI: 10.1371/journal.pone.0199334] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 06/05/2018] [Indexed: 11/19/2022] Open
Abstract
Background Sialylated glycoconjugates play important roles in physiological and pathological processes. However, available sialylated oligosaccharides source is limited which is a barrier to study their biological roles. This work reports an efficient approach to produce sialic acid-modified lactuloses and investigates their inhibitory effects on Staphylococcus aureus (S. aureus). Methods A one-pot two-enzyme (OPTE) sialylation system was used to efficiently synthesize sialylated lactuloses. Silica gel flash chromatography column was employed to purify the sialylated products. The purity and identity of the product structures were confirmed with mass spectrometry (MS) and nuclear magnetic resonance (NMR). The inhibitory effect of sialylated lactuloses against S. aureus was evaluated by using microplate assay, fluorescence microscopy, DAPI (4',6-diamidino-2-phenylindole) fluorescence staining and protein leakage quantification. Results Neu5Ac-containing sialylated lactuloses with either α2,3- or α2,6-linkages were efficiently synthesized via an efficient OPTE sialylation system using α-2,3-sialyltransferase or α-2,6-sialyltransferase, respectively. Neu5Ac-α2,3-lactulose and Neu5Ac-α2,6-lactulose significantly inhibited the growth of S. aureus. Fluorescence microscopy and DAPI fluorescence staining indicated that the sialylated lactuloses might disrupt nucleic acid synthesis of S. aureus. Conclusions Neu5Ac-containing sialylated lactuloses had higher antibacterial activity against S. aureus than non-sialylated lactulose. The inhibitory effect of Neu5Ac-α2,3-lactulose was superior to that of Neu5Ac-α2,6-lactulose. The sialylated lactuloses might inhibit S. aureus by causing cell membrane leakage and disrupting nucleic acid synthesis.
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Affiliation(s)
- Jie Zeng
- School of Food Science, Henan Institute of Science and Technology, Xinxiang, China
- * E-mail:
| | - Yajie Hu
- School of Food Science, Henan Institute of Science and Technology, Xinxiang, China
| | - Tian Jia
- School of Food Science, Henan Institute of Science and Technology, Xinxiang, China
| | - Ruiyao Zhang
- School of Food Science, Henan Institute of Science and Technology, Xinxiang, China
| | - Tongchao Su
- School of Food Science, Henan Institute of Science and Technology, Xinxiang, China
| | - Junliang Sun
- School of Food Science, Henan Institute of Science and Technology, Xinxiang, China
| | - Haiyan Gao
- School of Food Science, Henan Institute of Science and Technology, Xinxiang, China
| | - Guanglei Li
- School of Food Science, Henan Institute of Science and Technology, Xinxiang, China
| | - Meng Cao
- School of Food Science, Henan Institute of Science and Technology, Xinxiang, China
| | - Mengdi Song
- School of Food Science, Henan Institute of Science and Technology, Xinxiang, China
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18
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Yu H, Li Y, Wu Z, Li L, Zeng J, Zhao C, Wu Y, Tasnima N, Wang J, Liu H, Gadi MR, Guan W, Wang PG, Chen X. H. pylori α1-3/4-fucosyltransferase (Hp3/4FT)-catalyzed one-pot multienzyme (OPME) synthesis of Lewis antigens and human milk fucosides. Chem Commun (Camb) 2018; 53:11012-11015. [PMID: 28936496 DOI: 10.1039/c7cc05403c] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Helicobacter pylori α1-3/4-fucosyltransferase (Hp3/4FT) was expressed in Escherichia coli at a level of 30 mg L-1 culture and used as a diverse catalyst in a one-pot multienzyme (OPME) system for high-yield production of l-fucose-containing carbohydrates including Lewis antigens such as Lewis a, b, and x, O-sulfated Lewis x, and sialyl Lewis x and human milk fucosides such as 3-fucosyllactose (3-FL), lacto-N-fucopentaose (LNFP) III, and lacto-N-difuco-hexaose (LNDFH) II and III. Noticeably, while difucosylation of tetrasaccharides was readily achieved using an excess amount of donor, the synthesis of LNFP III was achieved by Hp3/4FT-catalyzed selective fucosylation of the N-acetyllactosamine (LacNAc) component in lacto-N-neotetraose (LNnT).
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Affiliation(s)
- Hai Yu
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA.
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Han Z, Chen C, Meng C, Gao T, Peng P, Chen X, Wang F, Cao H. Chemoenzymatic synthesis of tumor-associated antigen N3 minor octasaccharide. J Carbohydr Chem 2017. [DOI: 10.1080/07328303.2017.1315123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Zhipeng Han
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, and School of Pharmaceutical Sciences, Shandong University, Jinan, China
| | - Congcong Chen
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, and School of Pharmaceutical Sciences, Shandong University, Jinan, China
| | - Caicai Meng
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, and School of Pharmaceutical Sciences, Shandong University, Jinan, China
| | - Tian Gao
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, and School of Pharmaceutical Sciences, Shandong University, Jinan, China
| | - Peng Peng
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, and School of Pharmaceutical Sciences, Shandong University, Jinan, China
| | - Xi Chen
- Department of Chemistry, University of California, Davis, California, USA
| | - Fengshan Wang
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, and School of Pharmaceutical Sciences, Shandong University, Jinan, China
- Key Laboratory of Chemical Biology of Natural Products (Ministry of Education), Institute of Biochemical and Biotechnological Drugs, Shandong University, Jinan, China
| | - Hongzhi Cao
- National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, and School of Pharmaceutical Sciences, Shandong University, Jinan, China
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, China
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McArthur JB, Yu H, Zeng J, Chen X. Converting Pasteurella multocidaα2-3-sialyltransferase 1 (PmST1) to a regioselective α2-6-sialyltransferase by saturation mutagenesis and regioselective screening. Org Biomol Chem 2017; 15:1700-1709. [PMID: 28134951 DOI: 10.1039/c6ob02702d] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A microtiter plate-based screening assay capable of determining the activity and regioselectivity of sialyltransferases was developed. This assay was used to screen two single-site saturation libraries of Pasteurella multocidaα2-3-sialyltransferase 1 (PmST1) for α2-6-sialyltransferase activity and total sialyltransferase activity. PmST1 double mutant P34H/M144L was found to be the most effective α2-6-sialyltransferase and displayed 50% reduced donor hydrolysis and 50-fold reduced sialidase activity compared to the wild-type PmST1. It retained the donor substrate promiscuity of the wild-type enzyme and was used in an efficient one-pot multienzyme (OPME) system to selectively catalyze the sialylation of the terminal galactose residue in a multigalactose-containing tetrasaccharide lacto-N-neotetraoside.
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Affiliation(s)
- John B McArthur
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616, USA.
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