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Gattani A, Agrawal A, Khan MH, Gupta R, Singh P. Evaluation of catalytic activity of human and animal origin viral neuraminidase: Current prospect. Anal Biochem 2023; 671:115157. [PMID: 37061113 DOI: 10.1016/j.ab.2023.115157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 04/12/2023] [Indexed: 04/17/2023]
Abstract
With the exception of plants, almost all living organisms synthesize neuraminidase/sialidase. It is a one among the crucial proteins that controls how virulent a microorganism is. An essential enzyme in orthomyxoviruses and paramyxoviruses that destroys receptors is neuraminidase. It plays a number of roles throughout the viral life cycle in addition to one that involves the release of progeny virus particles. This protein is an important target for therapeutic interventions and diagnostic assays. Neuraminidase inhibitors effectively prevent the spread of disease and viral infection. Sensitive, quick, and inexpensive high throughput assays are needed to screen for specific neuraminidase inhibitory chemicals. To characterize the neuraminidase catalytic activity, however, the traditional assays are still the most common in laboratories. This review gives a brief overview of these neuraminidase assays and recent, innovative developments, particularly those involving biosensors.
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Affiliation(s)
- Anil Gattani
- Department of Veterinary Biochemistry, College of Veterinary Science & Animal Husbandry, Jabalpur, M.P, India.
| | - Aditya Agrawal
- Department of Veterinary Biochemistry, College of Veterinary Science & Animal Husbandry, Rewa, M.P, India
| | - M Hira Khan
- Department of Veterinary Biochemistry, College of Veterinary Science & Animal Husbandry, Jabalpur, M.P, India
| | - Rohini Gupta
- Department of Medicine, College of Veterinary Science & Animal Husbandry, Jabalpur, M.P, India
| | - Praveen Singh
- Division of Biochemistry, ICAR-Indian Veterinary Research Institute Izatnagar, 243122, Bareilly, UP, India; Biophysics Section, ICAR-Indian Veterinary Research Institute Izatnagar, 243122, Bareilly, UP, India
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2
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Rosenau J, Grothaus IL, Yang Y, Kumar ND, Ciacchi LC, Kelm S, Waespy M. N-glycosylation modulates enzymatic activity of Trypanosoma congolense trans-sialidase. J Biol Chem 2022; 298:102403. [PMID: 35995210 PMCID: PMC9493392 DOI: 10.1016/j.jbc.2022.102403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 08/15/2022] [Accepted: 08/16/2022] [Indexed: 11/24/2022] Open
Abstract
Trypanosomes cause the devastating disease trypanosomiasis, in which the action of trans-sialidase (TS) enzymes harbored on their surface is a key virulence factor. TS enzymes are N-glycosylated, but the biological functions of their glycans have remained elusive. In this study, we investigated the influence of N-glycans on the enzymatic activity and structural stability of TconTS1, a recombinant TS from the African parasite Trypanosoma congolense. We expressed the enzyme in Chinese hamster ovary Lec1 cells, which produce high-mannose type N-glycans similar to the TS N-glycosylation pattern in vivo. Our MALDI-TOF mass spectrometry data revealed that up to eight putative N-glycosylation sites were glycosylated. In addition, we determined that N-glycan removal via endoglycosidase Hf treatment of TconTS1 led to a decrease in substrate affinity relative to the untreated enzyme but had no impact on the conversion rate. Furthermore, we observed no changes in secondary structure elements of hypoglycosylated TconTS1 in CD experiments. Finally, our molecular dynamics simulations provided evidence for interactions between monosaccharide units of the highly flexible N-glycans and some conserved amino acids located at the catalytic site. These interactions led to conformational changes, possibly enhancing substrate accessibility and enzyme–substrate complex stability. The here-observed modulation of catalytic activity via N-glycans represents a so-far-unknown structure–function relationship potentially inherent in several members of the TS enzyme family.
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Affiliation(s)
- Jana Rosenau
- University of Bremen, Centre for Biomolecular Interactions Bremen, Faculty for Biology and Chemistry, 28359 Bremen, Germany
| | - Isabell Louise Grothaus
- University of Bremen, Centre for Biomolecular Interactions Bremen, Faculty for Biology and Chemistry, 28359 Bremen, Germany; University of Bremen, Hybrid Materials Interfaces Group, Faculty of Production Engineering, Bremen Center for Computational Materials Science, Center for Environmental Research and Sustainable Technology (UFT), and MAPEX Center for Materials and Processes, 28359 Bremen, Germany
| | - Yikun Yang
- University of Bremen, Centre for Biomolecular Interactions Bremen, Faculty for Biology and Chemistry, 28359 Bremen, Germany
| | - Nilima Dinesh Kumar
- University of Bremen, Centre for Biomolecular Interactions Bremen, Faculty for Biology and Chemistry, 28359 Bremen, Germany
| | - Lucio Colombi Ciacchi
- University of Bremen, Hybrid Materials Interfaces Group, Faculty of Production Engineering, Bremen Center for Computational Materials Science, Center for Environmental Research and Sustainable Technology (UFT), and MAPEX Center for Materials and Processes, 28359 Bremen, Germany
| | - Sørge Kelm
- University of Bremen, Centre for Biomolecular Interactions Bremen, Faculty for Biology and Chemistry, 28359 Bremen, Germany
| | - Mario Waespy
- University of Bremen, Centre for Biomolecular Interactions Bremen, Faculty for Biology and Chemistry, 28359 Bremen, Germany.
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Waespy M, Gbem TT, Dinesh Kumar N, Solaiyappan Mani S, Rosenau J, Dietz F, Kelm S. Cooperativity of catalytic and lectin-like domain of Trypanosoma congolense trans-sialidase modulates its catalytic activity. PLoS Negl Trop Dis 2022; 16:e0009585. [PMID: 35130274 PMCID: PMC8865650 DOI: 10.1371/journal.pntd.0009585] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 02/23/2022] [Accepted: 01/23/2022] [Indexed: 12/15/2022] Open
Abstract
Trans-sialidases (TS) represent a multi-gene family of unusual enzymes, which catalyse the transfer of terminal sialic acids (Sia) from sialoglycoconjugates to terminal galactose or N-acetylgalactosamine residues of oligosaccharides without the requirement of CMP-Neu5Ac, the activated Sia used by typical sialyltransferases. Enzymes comprise a N-terminal catalytic domain (CD) followed by a lectin-like domain (LD). Most work on trypanosomal TS has been done on enzymatic activities focusing on the CD of TS from Trypanosoma cruzi (causing Chagas disease in Latin America), subspecies of Trypanosoma brucei, (causing human sleeping sickness in Africa) and Trypanosoma congolense (causing African Animal Trypanosomosis in livestock). Previously, we demonstrated that T. congolense TS (TconTS)-LD binds to several carbohydrates, such as 1,4-β-mannotriose. In this study we investigated the influence of TconTS3-LD on Sia transfer efficiency of TconTS1a-CD by swapping domains. in silico analysis on structure models of TconTS enzymes revealed the potential of domain swaps between TconTS1a and TconTS3 without structural disruptions of the enzymes overall topologies. Recombinant domain swapped TconTS1a/TS3 showed clear Sia transfer activity, when using fetuin and lactose as Sia donor and acceptor substrates, respectively. While Sia transfer activity remained unchanged from the level of TconTS1a, hydrolytic release of free Neu5Ac as a side product was suppressed resulting in increased transfer efficiency. Presence of 1,4-β-mannotriose during TS reactions modulates enzyme activities enhancing transfer efficiency possibly due to occupation of the binding site in TconTS1a-LD. Interestingly this effect was in the same range as that observed when swapping TconTS1a-CD and TconTS3-LD. In summary, this study demonstrate the proof-of-principle for swapping CDs and LDs of TconTS and that TconTS3-LD influences enzymatic activity of TconTS1a-CD providing evidence that LDs play pivotal roles in modulating activities and biological functions of TconTS and possibly other TS.
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Affiliation(s)
- Mario Waespy
- Centre for Biomolecular Interactions Bremen, Faculty for Biology and Chemistry, University Bremen, Bremen, Germany
| | - Thaddeus Termulun Gbem
- Africa Centre of Excellence for Neglected Tropical Diseases and Forensic Biotechnology, Ahmadu Bello University, Zaria, Nigeria, Africa
- Department of Biology, Ahmadu Bello University, Zaria, Nigeria, Africa
| | - Nilima Dinesh Kumar
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Shanmugam Solaiyappan Mani
- Centre for Biomolecular Interactions Bremen, Faculty for Biology and Chemistry, University Bremen, Bremen, Germany
| | - Jana Rosenau
- Centre for Biomolecular Interactions Bremen, Faculty for Biology and Chemistry, University Bremen, Bremen, Germany
| | - Frank Dietz
- Centre for Biomolecular Interactions Bremen, Faculty for Biology and Chemistry, University Bremen, Bremen, Germany
| | - Sørge Kelm
- Centre for Biomolecular Interactions Bremen, Faculty for Biology and Chemistry, University Bremen, Bremen, Germany
- Africa Centre of Excellence for Neglected Tropical Diseases and Forensic Biotechnology, Ahmadu Bello University, Zaria, Nigeria, Africa
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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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5
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Campetella O, Buscaglia CA, Mucci J, Leguizamón MS. Parasite-host glycan interactions during Trypanosoma cruzi infection: trans-Sialidase rides the show. Biochim Biophys Acta Mol Basis Dis 2020; 1866:165692. [PMID: 31972227 DOI: 10.1016/j.bbadis.2020.165692] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 01/07/2020] [Accepted: 01/15/2020] [Indexed: 12/11/2022]
Abstract
Many important pathogen-host interactions rely on highly specific carbohydrate binding events. In the case of the protozoan Trypanosoma cruzi, the causative agent of Chagas disease, glycointeractions involving sialic acid (SA) residues are pivotal for parasite infectivity, escape from immune surveillance and pathogenesis. Though unable to synthesize SA de novo, T. cruzi displays a unique trans-Sialidase (TS) enzyme, which is able to cleave terminal SA residues from host donor glycoconjugates and transfer them onto parasite surface mucins, thus generating protective/adhesive structures. In addition, this parasite sheds TS into the bloodstream, as a way of modifying the surface SA signature, and thereby the signaling/functional properties of mammalian host target cells on its own advantage. Here, we discuss the pathogenic aspects of T. cruzi TS: its molecular adaptations, the multiplicity of interactions in which it is involved during infections, and the array of novel and appealing targets for intervention in Chagas disease provided by TS-remodeled sialoglycophenotypes.
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Affiliation(s)
- Oscar Campetella
- Instituto de Investigaciones Biotecnológicas, Universidad Nacional de San Martín and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina.
| | - Carlos A Buscaglia
- Instituto de Investigaciones Biotecnológicas, Universidad Nacional de San Martín and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Juan Mucci
- Instituto de Investigaciones Biotecnológicas, Universidad Nacional de San Martín and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - María Susana Leguizamón
- Instituto de Investigaciones Biotecnológicas, Universidad Nacional de San Martín and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
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6
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Mule SN, Saad JS, Fernandes LR, Stolf BS, Cortez M, Palmisano G. Protein glycosylation inLeishmaniaspp. Mol Omics 2020; 16:407-424. [DOI: 10.1039/d0mo00043d] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Protein glycosylation is a co- and post-translational modification that, inLeishmaniaparasites, plays key roles in vector–parasite–vertebrate host interaction.
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Affiliation(s)
- Simon Ngao Mule
- GlycoProteomics Laboratory
- Department of Parasitology
- Institute of Biomedical Sciences
- University of Sao Paulo
- Sao Paulo - 05508-000
| | - Joyce Silva Saad
- GlycoProteomics Laboratory
- Department of Parasitology
- Institute of Biomedical Sciences
- University of Sao Paulo
- Sao Paulo - 05508-000
| | - Livia Rosa Fernandes
- GlycoProteomics Laboratory
- Department of Parasitology
- Institute of Biomedical Sciences
- University of Sao Paulo
- Sao Paulo - 05508-000
| | - Beatriz S. Stolf
- Department of Parasitology
- Institute of Biomedical Sciences
- University of Sao Paulo
- Sao Paulo
- Brazil
| | - Mauro Cortez
- Department of Parasitology
- Institute of Biomedical Sciences
- University of Sao Paulo
- Sao Paulo
- Brazil
| | - Giuseppe Palmisano
- GlycoProteomics Laboratory
- Department of Parasitology
- Institute of Biomedical Sciences
- University of Sao Paulo
- Sao Paulo - 05508-000
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7
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Teixeira AF, Pereira JG, Pestana-Ascensão S, Silva MS. Trans-sialidase Protein as a Potential Serological Marker for African Trypanosomiasis. Protein J 2019; 38:50-57. [PMID: 30604107 DOI: 10.1007/s10930-018-09808-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Trypanosoma brucei is the etiological agent of African trypanosomiasis responsible for human and animal infections. T. brucei is transmitted by infected tsetse flies. There is no vaccine for the disease and drugs available for treatment are inefficient and high toxicity. In this context, it is a priority to find antigenic targets suitable for the development of new diagnostic tools, drugs and vaccines. In this work, we report that mice infected with T. b. brucei produce antibodies against trans-sialidase recombinant protein (TS). In addition, we also demonstrate that bloodstream T. b. brucei express messenger RNA related to the TS gene. Collectively, our data strongly suggest that bloodstream forms of T. b. brucei also express the TS gene, that to date was described only in the procyclic forms of the T. b. brucei. In conclusion, these results highlight the importance of TS protein as a possible antigen target during infection caused by T. b. brucei.
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Affiliation(s)
- Ana Filipa Teixeira
- Global Health and Tropical Medicine, Institute of Hygiene and Tropical Medicine, Universidade Nova de Lisboa, Lisbon, Portugal
| | - João Gomes Pereira
- Global Health and Tropical Medicine, Institute of Hygiene and Tropical Medicine, Universidade Nova de Lisboa, Lisbon, Portugal
| | - Sónia Pestana-Ascensão
- Global Health and Tropical Medicine, Institute of Hygiene and Tropical Medicine, Universidade Nova de Lisboa, Lisbon, Portugal
| | - Marcelo Sousa Silva
- Global Health and Tropical Medicine, Institute of Hygiene and Tropical Medicine, Universidade Nova de Lisboa, Lisbon, Portugal. .,Immunoparasitology Laboratory, Department of Clinical and Toxicological Analysis, Federal University of Rio Grande do Norte, Natal, Brazil. .,Programa de Pós-graduação em Bioquímica, Centro de Biociências, Federal University of Rio Grande do Norte, Natal, Brazil. .,Programa de Pós-graduação em Ciências Farmacêuticas, Centro de Ciências da Saúde, Federal University of Rio Grande do Norte, Natal, Brazil.
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8
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Abstract
Sialic acids are cytoprotectors, mainly localized on the surface of cell membranes with multiple and outstanding cell biological functions. The history of their structural analysis, occurrence, and functions is fascinating and described in this review. Reports from different researchers on apparently similar substances from a variety of biological materials led to the identification of a 9-carbon monosaccharide, which in 1957 was designated "sialic acid." The most frequently occurring member of the sialic acid family is N-acetylneuraminic acid, followed by N-glycolylneuraminic acid and O-acetylated derivatives, and up to now over about 80 neuraminic acid derivatives have been described. They appeared first in the animal kingdom, ranging from echinoderms up to higher animals, in many microorganisms, and are also expressed in insects, but are absent in higher plants. Sialic acids are masks and ligands and play as such dual roles in biology. Their involvement in immunology and tumor biology, as well as in hereditary diseases, cannot be underestimated. N-Glycolylneuraminic acid is very special, as this sugar cannot be expressed by humans, but is a xenoantigen with pathogenetic potential. Sialidases (neuraminidases), which liberate sialic acids from cellular compounds, had been known from very early on from studies with influenza viruses. Sialyltransferases, which are responsible for the sialylation of glycans and elongation of polysialic acids, are studied because of their significance in development and, for instance, in cancer. As more information about the functions in health and disease is acquired, the use of sialic acids in the treatment of diseases is also envisaged.
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Affiliation(s)
- Roland Schauer
- Biochemisches Institut, Christian-Albrechts-Universität zu Kiel, Kiel, Germany.
| | - Johannis P Kamerling
- Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, The Netherlands.
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9
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Waespy M, Gbem TT, Elenschneider L, Jeck AP, Day CJ, Hartley-Tassell L, Bovin N, Tiralongo J, Haselhorst T, Kelm S. Carbohydrate Recognition Specificity of Trans-sialidase Lectin Domain from Trypanosoma congolense. PLoS Negl Trop Dis 2015; 9:e0004120. [PMID: 26474304 PMCID: PMC4608562 DOI: 10.1371/journal.pntd.0004120] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2015] [Accepted: 09/05/2015] [Indexed: 12/18/2022] Open
Abstract
Fourteen different active Trypanosoma congolense trans-sialidases (TconTS), 11 variants of TconTS1 besides TconTS2, TconTS3 and TconTS4, have been described. Notably, the specific transfer and sialidase activities of these TconTS differ by orders of magnitude. Surprisingly, phylogenetic analysis of the catalytic domains (CD) grouped each of the highly active TconTS together with the less active enzymes. In contrast, when aligning lectin-like domains (LD), the highly active TconTS grouped together, leading to the hypothesis that the LD of TconTS modulates its enzymatic activity. So far, little is known about the function and ligand specificity of these LDs. To explore their carbohydrate-binding potential, glycan array analysis was performed on the LD of TconTS1, TconTS2, TconTS3 and TconTS4. In addition, Saturation Transfer Difference (STD) NMR experiments were done on TconTS2-LD for a more detailed analysis of its lectin activity. Several mannose-containing oligosaccharides, such as mannobiose, mannotriose and higher mannosylated glycans, as well as Gal, GalNAc and LacNAc containing oligosaccharides were confirmed as binding partners of TconTS1-LD and TconTS2-LD. Interestingly, terminal mannose residues are not acceptor substrates for TconTS activity. This indicates a different, yet unknown biological function for TconTS-LD, including specific interactions with oligomannose-containing glycans on glycoproteins and GPI anchors found on the surface of the parasite, including the TconTS itself. Experimental evidence for such a scenario is presented.
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Affiliation(s)
- Mario Waespy
- Centre for Biomolecular Interactions Bremen, Faculty for Biology and Chemistry, University Bremen, Bremen, Germany
| | - Thaddeus T. Gbem
- Centre for Biomolecular Interactions Bremen, Faculty for Biology and Chemistry, University Bremen, Bremen, Germany
- Africa Centre of Excellence for Neglected Tropical Diseases and Forensic Biotechnology, Ahmadu Bello University, Zaria, Nigeria
| | - Leroy Elenschneider
- Centre for Biomolecular Interactions Bremen, Faculty for Biology and Chemistry, University Bremen, Bremen, Germany
| | - André-Philippe Jeck
- Centre for Biomolecular Interactions Bremen, Faculty for Biology and Chemistry, University Bremen, Bremen, Germany
| | - Christopher J. Day
- Institute for Glycomics, Griffith University Gold Coast Campus, Queensland, Australia
| | | | - Nicolai Bovin
- Shemyakin Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Joe Tiralongo
- Institute for Glycomics, Griffith University Gold Coast Campus, Queensland, Australia
| | - Thomas Haselhorst
- Institute for Glycomics, Griffith University Gold Coast Campus, Queensland, Australia
| | - Sørge Kelm
- Centre for Biomolecular Interactions Bremen, Faculty for Biology and Chemistry, University Bremen, Bremen, Germany
- Africa Centre of Excellence for Neglected Tropical Diseases and Forensic Biotechnology, Ahmadu Bello University, Zaria, Nigeria
- Institute for Glycomics, Griffith University Gold Coast Campus, Queensland, Australia
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Park SS, Gervay-Hague J. Synthesis of partially O-acetylated N-acetylneuraminic acid using regioselective silyl exchange technology. Org Lett 2014; 16:5044-7. [PMID: 25247390 PMCID: PMC4184446 DOI: 10.1021/ol502389g] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
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Postglycosylation acetylation of
sialic acid imparts unique roles
to sialoglycoconjugates in mammalian immune response making structural
and functional understanding of these analogues important. Five partially O-acetylated Neu5Ac analogues have been synthesized. Reaction
of per-O-silylated Neu5Ac ester with AcOH and Ac2O in pyridine promotes regioselective silyl ether/acetate
exchange in the following order: C4 (2°) > C9 (1°) > C8 (2°) > C2 (anomeric).
Subsequent hydrogenolysis affords the corresponding sialic acid analogues
as useful chemical biology tools.
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Affiliation(s)
- Simon S Park
- Department of Chemistry, University of California, Davis , One Shields Avenue, Davis, California 95616, United States
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11
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Biochemical diversity in the Trypanosoma congolense trans-sialidase family. PLoS Negl Trop Dis 2013; 7:e2549. [PMID: 24340108 PMCID: PMC3855035 DOI: 10.1371/journal.pntd.0002549] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 10/04/2013] [Indexed: 02/01/2023] Open
Abstract
Trans-sialidases are key enzymes in the life cycle of African trypanosomes in both, mammalian host and insect vector and have been associated with the disease trypanosomiasis, namely sleeping sickness and nagana. Besides the previously reported TconTS1, we have identified three additional active trans-sialidases, TconTS2, TconTS3 and TconTS4, and three trans-sialidase like genes in Trypanosoma congolense. At least TconTS1, TconTS2 and TconTS4 are found in the bloodstream of infected animals. We have characterised the enzymatic properties of recombinant proteins expressed in eukaryotic fibroblasts using fetuin as model blood glycoprotein donor substrate. One of the recombinant trans-sialidases, TconTS2, had the highest specific activity reported thus far with very low sialidase activity. The active trans-sialidases share all the amino acids critical for the catalytic reaction with few variations in the predicted binding site for the leaving or acceptor glycan. However, these differences cannot explain the orders of magnitudes between their transfer activities, which must be due to other unidentified structural features of the proteins or substrates selectivity. Interestingly, the phylogenetic relationships between the lectin domains correlate with their specific trans-sialylation activities. This raises the question whether and how the lectin domains regulate the trans-sialidase reaction. The identification and enzymatic characterisation of the trans-sialidase family in T. congolense will contribute significantly towards the understanding of the roles of these enzymes in the pathogenesis of Animal African Trypanosomiasis. Trypanosomiasis is a disease also known as sleeping sickness in humans (Human African Trypanosomiasis) and nagana in animals (Animal African Trypanosomiasis). This disease is caused by protozoan parasites of the genus Trypanosoma. Tsetse flies are responsible for the transmission of these parasites. Trypanosoma congolense is the main causative agent of nagana in cattle. The clinical signs of the disease have been linked to the presence of an enzyme called trans-sialidase. Interestingly, the enzyme alternates in different forms in the mammalian and the insect vector. Previous knowledge had shown that the parasite requires the enzyme for survival in the fly vector. Our current work has revealed other forms of the enzyme that could be essential for the persistence of the disease in mammalian and vector hosts. These enzymes, though similar in structural architecture, show differences in their activities that could be key in delineating their individual roles in the pathophysiology of the disease.
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12
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Mitchell FL, Neres J, Ramraj A, Raju RK, Hillier IH, Vincent MA, Bryce RA. Insights into the activity and specificity of Trypanosoma cruzi trans-sialidase from molecular dynamics simulations. Biochemistry 2013; 52:3740-51. [PMID: 23672572 PMCID: PMC3675669 DOI: 10.1021/bi301112p] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
![]()
Trypanosoma cruzitrans-sialidase
(TcTS), which catalyzes the transfer or hydrolysis of terminal sialic
acid residues, is crucial to the development and proliferation of
the T. cruzi parasite and thus has emerged as a potential
drug target for the treatment of Chagas disease. We here probe the
origin of the observed preference for the transfer reaction over hydrolysis
where the substrate for TcTS is the natural sialyl donor (represented
in this work by sialyllactose). Thus, acceptor lactose preferentially
attacks the sialyl-enyzme intermediate rather than water. We compare
this with the weaker preference for such transfer shown by a synthetic
donor substrate, 4-methylumbelliferyl α-d-acetylneuraminide.
For this reason, we conducted molecular dynamics simulations of TcTS
following its sialylation by the substrate to examine the behavior
of the asialyl leaving group by the protein. These simulations indicate
that, where lactose is released, this leaving group samples well-defined
interactions in the acceptor site, some of which are mediated by localized
water molecules; also, the extent of the opening of the acceptor site
to solvent is reduced as compared with those of unliganded forms of
TcTS. However, where there is release of 4-methylumbelliferone, this
leaving group explores a range of transient poses; surrounding active
site water is also more disordered. The acceptor site explores more
open conformations, similar to the case in which the 4-methylumbelliferone
is absent. Thus, the predicted solvent accessibility of sialylated
TcTS is increased when 4-methylumbelliferyl α-d-acetylneuraminide
is the substrate compared to sialyllactose; this in turn is likely
to contribute to a greater propensity for hydrolysis of the covalent
intermediate. These computational simulations, which suggest that
protein flexibility has a role in the transferase/sialidase activity
of TcTS, have the potential to aid in the design of anti-Chagas inhibitors
effective against this neglected tropical disease.
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Affiliation(s)
- Felicity L Mitchell
- School of Pharmacy and Pharmaceutical Sciences and ‡School of Chemistry, University of Manchester , Oxford Road, Manchester M13 9PT, U.K
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13
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Guegan F, Plazolles N, Baltz T, Coustou V. Erythrophagocytosis of desialylated red blood cells is responsible for anaemia during Trypanosoma vivax infection. Cell Microbiol 2013; 15:1285-303. [PMID: 23421946 DOI: 10.1111/cmi.12123] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Revised: 02/05/2013] [Accepted: 02/07/2013] [Indexed: 11/26/2022]
Abstract
Trypanosomal infection-induced anaemia is a devastating scourge for cattle in widespread regions. Although Trypanosoma vivax is considered as one of the most important parasites regarding economic impact in Africa and South America, very few in-depth studies have been conducted due to the difficulty of manipulating this parasite. Several hypotheses were proposed to explain trypanosome induced-anaemia but mechanisms have not yet been elucidated. Here, we characterized a multigenic family of trans-sialidases in T. vivax, some of which are released into the host serum during infection. These enzymes are able to trigger erythrophagocytosis by desialylating the major surface erythrocytes sialoglycoproteins, the glycophorins. Using an ex vivo assay to quantify erythrophagocytosis throughout infection, we showed that erythrocyte desialylation alone results in significant levels of anaemia during the acute phase of the disease. Characterization of virulence factors such as the trans-sialidases is vital to develop a control strategy against the disease or parasite.
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Affiliation(s)
- Fabien Guegan
- Microbiologie fondamentale et Pathogénicité, UMR 5234, Université de Bordeaux, Bordeaux, France
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14
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Coustou V, Plazolles N, Guegan F, Baltz T. Sialidases play a key role in infection and anaemia in Trypanosoma congolense animal trypanosomiasis. Cell Microbiol 2012; 14:431-45. [PMID: 22136727 DOI: 10.1111/j.1462-5822.2011.01730.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Animal African trypanosomiasis is a major constraint to livestock productivity and has an important impact on millions of people in developing African countries. This parasitic disease, caused mainly by Trypanosoma congolense, results in severe anaemia leading to animal death. In order to characterize potential targets for an anti-disease vaccine, we investigated a multigenic trans-sialidase family (TcoTS) in T. congolense. Sialidase and trans-sialidase activities were quantified for the first time, as well as the tightly regulated TcoTS expression pattern throughout the life cycle. Active enzymes were expressed in bloodstream form parasites and released into the blood during infection. Using genetic tools, we demonstrated a significant correlation between TcoTS silencing and impairment of virulence during experimental infection with T. congolense. Reduced TcoTS expression affected infectivity, parasitaemia and pathogenesis development. Immunization-challenge experiments using recombinant TcoTS highlighted their potential protective use in an anti-disease vaccine.
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Affiliation(s)
- Virginie Coustou
- Univ. de Bordeaux, Microbiologie fondamentale et Pathogénicité, Bordeaux, France.
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15
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Nakatani F, Morita YS, Ashida H, Nagamune K, Maeda Y, Kinoshita T. Identification of a second catalytically active trans-sialidase in Trypanosoma brucei. Biochem Biophys Res Commun 2011; 415:421-5. [PMID: 22040733 DOI: 10.1016/j.bbrc.2011.10.085] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2011] [Accepted: 10/17/2011] [Indexed: 10/16/2022]
Abstract
The procyclic stage of Trypanosoma brucei is covered by glycosylphosphatidylinositol (GPI)-anchored surface proteins called procyclins. The procyclin GPI anchor contains a side chain of N-acetyllactosamine repeats terminated by sialic acids. Sialic acid modification is mediated by trans-sialidases expressed on the parasite's cell surface. Previous studies suggested the presence of more than one active trans-sialidases, but only one has so far been reported. Here we cloned and examined enzyme activities of four additional trans-sialidase homologs, and show that one of them, Tb927.8.7350, encodes another active trans-sialidase, designated as TbSA C2. In an in vitro assay, TbSA C2 utilized α2-3 sialyllactose as a donor, and produced an α2-3-sialylated product, suggesting that it is an α2-3 trans-sialidase. We suggest that TbSA C2 plays a role in the sialic acid modification of the trypanosome cell surface.
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Affiliation(s)
- Fumiki Nakatani
- Department of Immunoregulation, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
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16
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Schauer R, Kamerling JP. The Chemistry and Biology of Trypanosomal trans-Sialidases: Virulence Factors in Chagas Disease and Sleeping Sickness. Chembiochem 2011; 12:2246-64. [DOI: 10.1002/cbic.201100421] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Indexed: 11/10/2022]
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17
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Koliwer-Brandl H, Gbem TT, Waespy M, Reichert O, Mandel P, Drebitz E, Dietz F, Kelm S. Biochemical characterization of trans-sialidase TS1 variants from Trypanosoma congolense. BMC BIOCHEMISTRY 2011; 12:39. [PMID: 21801439 PMCID: PMC3173295 DOI: 10.1186/1471-2091-12-39] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Accepted: 07/30/2011] [Indexed: 02/01/2023]
Abstract
Background Animal African trypanosomiasis, sleeping sickness in humans and Nagana in cattle, is a resurgent disease in Africa caused by Trypanosoma parasites. Trans-sialidases expressed by trypanosomes play an important role in the infection cycle of insects and mammals. Whereas trans-sialidases of other trypanosomes like the American T. cruzi are well investigated, relatively little research has been done on these enzymes of T. congolense. Results Based on a partial sequence and an open reading frame in the WTSI database, DNA sequences encoding for eleven T. congolense trans-sialidase 1 variants with 96.3% overall amino acid identity were amplified. Trans-sialidase 1 variants were expressed as recombinant proteins, isolated and assayed for trans-sialylation activity. The purified proteins produced α2,3-sialyllactose from lactose by desialylating fetuin, clearly demonstrating their trans-sialidase activity. Using an HPLC-based assay, substrate specificities and kinetic parameters of two variants were characterized in detail indicating differences in substrate specificities for lactose, fetuin and synthetic substrates. Both enzymes were able to sialylate asialofetuin to an extent, which was sufficient to reconstitute binding sites for Siglec-4. A mass spectrometric analysis of the sialylation pattern of glycopeptides from fetuin revealed clear but generally similar changes in the sialylation pattern of the N-glycans on fetuin catalyzed by the trans-sialidases investigated. Conclusions The identification and characterization of a trans-sialidase gene family of the African parasite T. congolense has opened new perspectives for investigating the biological role of these enzymes in Nagana and sleeping sickness. Based on this study it will be interesting to address the expression pattern of these genes and their activities in the different stages of the parasite in its infection cycle. Furthermore, these trans-sialidases have the biotechnological potential to be used for enzymatic modification of sialylated glycoconjugates.
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Affiliation(s)
- Hendrik Koliwer-Brandl
- Centre for Biomolecular Interactions Bremen, Department of Biology and Chemistry, University of Bremen, Germany
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18
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Schauer R, Srinivasan GV, Wipfler D, Kniep B, Schwartz-Albiez R. O-Acetylated sialic acids and their role in immune defense. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 705:525-48. [PMID: 21618128 PMCID: PMC7123180 DOI: 10.1007/978-1-4419-7877-6_28] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Roland Schauer
- Biochemisches Institut, Christian-Albrechts-Universität, Olshausenstr 40, D-24098 Kiel, Germany.
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19
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Monti E, Bonten; E, D'Azzo A, Bresciani R, Venerando B, Borsani G, Schauer R, Tettamanti G. Sialidases in Vertebrates. Adv Carbohydr Chem Biochem 2010; 64:403-79. [DOI: 10.1016/s0065-2318(10)64007-3] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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20
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Agustí R, Giorgi ME, de Lederkremer RM. The trans-sialidase from Trypanosoma cruzi efficiently transfers alpha-(2-->3)-linked N-glycolylneuraminic acid to terminal beta-galactosyl units. Carbohydr Res 2007; 342:2465-9. [PMID: 17765882 DOI: 10.1016/j.carres.2007.07.018] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2007] [Revised: 07/20/2007] [Accepted: 07/24/2007] [Indexed: 11/16/2022]
Abstract
The trans-sialidase from Trypanosoma cruzi (TcTS), the agent of Chagas' disease, is a unique enzyme involved in mammalian host-cell invasion. Since T. cruzi is unable to synthesize sialic acids de novo, TcTS catalyzes the transfer of alpha-(2-->3)-sialyl residues from the glycoconjugates of the host to terminal beta-galactopyranosyl units present on the surface of the parasite. TcTS also plays a key role in the immunomodulation of the infected host. Chronic Chagas' disease patients elicit TcTS-neutralizing antibodies that are able to inhibit the enzyme. N-Glycolylneuraminic acid has been detected in T. cruzi, and the trans-sialidase was pointed out as the enzyme involved in its incorporation from host glycoconjugates. However, N-glycolylneuraminic acid alpha-(2-->3)-linked-containing oligosaccharides have not been analyzed as donors in the T. cruzi trans-sialidase reaction. In this paper we studied the ability of TcTS to transfer N-glycolylneuraminic acid from Neu5Gc(alpha2-->3)Gal(beta1-->4)GlcbetaOCH(2)CH(2)N(3) (1) and Neu5Gc(alpha2-->3)Gal(beta1-->3)GlcNAcbetaOCH(2)CH(2)N(3) (2) to lactitol, N-acetyllactosamine and lactose as acceptor substrates. Transfer from 1 was more efficient (50-65%) than from 2 (20-30%) for the three acceptors. The reactions were inhibited when the enzyme was preincubated with a neutralizing antibody. K(m) values were calculated for 1 and 2 and compared with 3'-sialyllactose using lactitol as acceptor substrate. Analysis was performed by high-performance anion-exchange (HPAEC) chromatography. A competitive transfer reaction of compound 1 in the presence of 3'-sialyllactose and N-acetyllactosamine showed a better transfer of Neu5Gc than of Neu5Ac.
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Affiliation(s)
- Rosalía Agustí
- CIHIDECAR, Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón II, 1428 Buenos Aires, Argentina
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21
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Buscaglia CA, Campo VA, Frasch ACC, Di Noia JM. Trypanosoma cruzi surface mucins: host-dependent coat diversity. Nat Rev Microbiol 2006; 4:229-36. [PMID: 16489349 DOI: 10.1038/nrmicro1351] [Citation(s) in RCA: 209] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The surface of the protozoan parasite Trypanosoma cruzi is covered in mucins, which contribute to parasite protection and to the establishment of a persistent infection. Their importance is highlighted by the fact that the approximately 850 mucin-encoding genes comprise approximately 1% of the parasite genome and approximately 6% of all predicted T. cruzi genes. The coordinate expression of a large repertoire of mucins containing variable regions in the mammal-dwelling stages of the T. cruzi life cycle suggests a possible strategy to thwart the host immune response. Here, we discuss the expression profiling of T. cruzi mucins, the mechanisms leading to the acquisition of mucin diversity and the possible consequences of a mosaic surface coat in the interplay between parasite and host.
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Affiliation(s)
- Carlos A Buscaglia
- Instituto de Investigaciones Biotecnológicas-Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de General San Martn-CONICET, San Martín (1650), Buenos Aires, Argentina
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22
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Schauer R. Sialic acids: fascinating sugars in higher animals and man. ZOOLOGY 2006; 107:49-64. [PMID: 16351927 DOI: 10.1016/j.zool.2003.10.002] [Citation(s) in RCA: 306] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2003] [Accepted: 10/13/2003] [Indexed: 01/29/2023]
Abstract
Sialic acids are acidic monosaccharides, which are among the most important molecules of higher animals, and occur in some microorganisms. They are bound to complex carbohydrates and occupy prominent positions, especially in cell membranes. Their structural diversity is high and, correspondingly, the mechanisms for their biosynthesis are complex. Sialic acid substituents strongly influence the activity of catabolic enzymes, in particular the sialidases, and thus the turnover rate of glycoconjugates. These sugars are involved in manifold cell functions. Due to the surface location of the acidic molecules they shield macromolecules and cells from enzymatic and immunological attacks. But they also represent recognition sites for various physiological receptors as well as for toxins and microorganisms, and thus allow their colonization. Many viruses use sialic acids for the infection of cells. As sialic acids also play a decisive role in tumor biology they prove to be rather versatile molecules that modulate cell biological events in a sensitive way. It is discussed that their evolvement may have stimulated evolution and rendered organisms less vulnerable to environmental attacks. However, disturbance of their metabolism may cause diseases.
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Affiliation(s)
- Roland Schauer
- Biochemical Institute, University of Kiel, Olshausenstrasse 40, D-24098 Kiel, Germany.
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23
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Useh NM, Ajanusi JO, Esievo KAN, Nok AJ. Characterization of a sialidase (neuraminidase) isolated fromClostridium chauvoei (Jakari strain). Cell Biochem Funct 2006; 24:347-52. [PMID: 15942928 DOI: 10.1002/cbf.1240] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A sialidase from Clostridium chauvoei (Jakari strain), an indigenous bacterial strain that causes blackleg in Nigerian cattle and other ruminants was isolated and partially purified by chromatography on DEAE cellulose, hydroxyapatite and phenyl agarose columns. The enzyme migrated as a 65-kDa protein after electrophoresis on sodium dodecyl sulphate polyacrylamide gels. It was optimally active at pH 4.5 and 40 degrees C with an activation energy (Ea) of 13.40 kJ mol(-1). It had Km and Vmax values of 170 microM and 200 micromole h(-1) mg(-1) respectively with fetuin as substrate. When sialyllactose (Neu5Ac2,3 lactose) was used as substrate the Km and Vmax values were 8 microM and 5 micromoles min(-1) mg(-1) respectively. The Clostridium chauvoei sialidase cleaved sialic acids from RBC ghosts of sheep, horse, goat, cattle, pig and mice as well as mouse brain cells, albeit at different rates. The enzyme was activated by Ca2+ and Mg2+ and inhibited by the group-specific reagents diethylpyrocarbonate (DEP) and N-ethylmalemide (NEM). The sialidase inhibitors, 2,3 didehydroneuraminic acid (Neu5Ac2,3en) and paranitrophenyl oxamic acid (pNPO) inhibited the enzyme competitively with Ki values of 40 and 30 microM respectively.
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Affiliation(s)
- N M Useh
- Department of Veterinary Pathology and Microbiology, Ahmadu Bello University, Zaria, Nigeria
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24
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Ryckaert S, Martens V, De Vusser K, Contreras R. Development of a S. cerevisiae whole cell biocatalyst for in vitro sialylation of oligosaccharides. J Biotechnol 2005; 119:379-88. [PMID: 15982773 DOI: 10.1016/j.jbiotec.2005.04.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2004] [Revised: 03/29/2005] [Accepted: 04/06/2005] [Indexed: 11/21/2022]
Abstract
Absence of sialylation on recombinant glycoproteins compromises their efficacy as therapeutic agents, as it results in rapid clearance from the human bloodstream. To circumvent this, several strategies are followed, including the implementation of a post-secretion glycosylation step. In this paper we describe the engineering of yeast cells expressing active surface exposed Trypanosoma cruzi trans-sialidase (TS) fused to the yeast Aga2 protein, and the use of this yeast in the sialylation of synthetic oligosaccharides. In an attempt to improve overall protein accessibility on the yeast surface, we abolished hyperglycosylation on the yeast cell wall proteins. This was achieved by disrupting the OCH1 gene of the TS surface expressing strain, which resulted in increased enzymatic activity. Using a fluorescence-based activity assay and DSA-FACE structural analysis, we obtained almost complete conversion to a fully sialylated acceptor, whereas in the wild type situation this conversion was only partial. Increasing protein accessibility on the yeast surface by modifying the glycosylation content thus proved to be a valuable approach in increasing the cell wall associated activity of an immobilised enzyme, hence resulting in a more effective biocatalyst system.
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Affiliation(s)
- Stefan Ryckaert
- Fundamental and Applied Molecular Biology, Department for Molecular Biomedical Research, Ghent University and VIB, FSVM-Research Building, Technologiepark 927, B-9052 Gent-Zwijnaarde, Belgium
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25
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Buratai LB, Nok AJ, Ibrahim S, Umar IA, Esievo KAN. Characterization of sialidase from bloodstream forms ofTrypanosoma vivax. Cell Biochem Funct 2005; 24:71-7. [PMID: 15898128 DOI: 10.1002/cbf.1189] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Sialidase (EC: 3.2.1.18) from Trypanosoma vivax (Agari Strain) was isolated from bloodstream forms of the parasite and purified to apparent electrophoretic homogeneity. The enzyme was purified 77-fold with a yield of 32% and co-eluted as a 66-kDa protein from a Sephadex G 110 column. The T. vivax sialidase was optimally active at 37 degrees C with an activation energy (E(a)) of 26.2 kJ mole(-1). The pH activity profile was broad with optimal activity at 6.5. The enzyme was activated by dithiothreitol and strongly inhibited by para-hydroxy mercuricbenzoate thus implicating a sulfhydryl group as a possible active site residue of the enzyme. Theenzyme hydrolysed Neu5Ac2,3lac and fetuin. It was inactive towards Neu5Ac2,6lac, colomic acid and the gangliosides GM1, and GDI. Initial velocity studies, for the determination of kinetic constants with fetuin as substrate gave a V(max) of 142.86 micromol h(-1) mg(-1) and a K(M) of 0.45 mM. The K(M) and V(max) with Neu5Ac-2,3lac were 0.17 mM and 840 micromole h(-1) mg(-1) respectively. The T. vivax sialidase was inhibited competitively by both 2,3 dideoxy neuraminic acid (Neu5Ac2,3en) and para-hydroxy oxamic acid. When ghost RBCs were used as substrates, the enzyme desialylated the RBCs from camel, goat, and zebu bull. The RBCs from dog, mouse and ndama bull were resistant to hydrolysis.
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Affiliation(s)
- L B Buratai
- Department of Biochemistry, University of Maiduguri, Nigeria
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26
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Schrader S, Tiralongo E, Paris G, Yoshino T, Schauer R. A nonradioactive 96-well plate assay for screening of trans-sialidase activity. Anal Biochem 2003; 322:139-47. [PMID: 14596820 DOI: 10.1016/j.ab.2003.07.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Trans-sialidase (E.C. 3.2.1.18) catalyzes the transfer of preferably alpha2,3-linked sialic acid to another glycan or glycoconjugate, forming a new alpha2,3 linkage to galactose or N-acetylgalactosamine. Here, we describe a nonradioactive 96-well plate fluorescence test for monitoring trans-sialidase activity with high sensitivity, specificity, and reproducibility using sialyllactose and 4-methylumbelliferyl-beta-D-galactoside as donor and acceptor substrates, respectively. The assay conditions were optimized using the trans-sialidase from Trypanosoma congolense and its general applicability was confirmed with recombinant trans-sialidase from Trypanosoma cruzi. Using this procedure, a large number of samples can be tested quickly and reliably, for instance in monitoring trans-sialidase during enzyme purification and the production of monoclonal antibodies, for enzyme characterization, and for identifying potential substrates and inhibitors. The trans-sialidase assay reported here was capable of detecting trans-sialidase activity in the low-mU range and may be a valuable tool in the search for further trans-sialidases in various biological systems.
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Affiliation(s)
- Silke Schrader
- Biochemisches Institut, Christian-Albrechts-Universität zu Kiel, 24098, Kiel, Germany.
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27
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Tiralongo E, Martensen I, Grötzinger J, Tiralongo J, Schauer R. Trans-sialidase-like sequences from Trypanosoma congolense conserve most of the critical active site residues found in other trans-sialidases. Biol Chem 2003; 384:1203-13. [PMID: 12974389 DOI: 10.1515/bc.2003.133] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Trypanosoma congolense is the agent of Nagana, the trypanosomiasis in African ruminants. Trypanosomes express an enzyme called trans-sialidase, which is believed to play an important role in maintaining pathogenicity of the parasites. Thus far, only two complete trans-sialidase sequences have been characterised, one from the American trypanosome T. cruzi and one from the African trypanosome T. brucei brucei. Although the crystal structure of T. cruzi trans-sialidase has recently been published [Buschiazzo et al., Mol. Cell 10 (2002), pp. 757-768], a number of questions concerning the exact transfer mechanism remain unanswered. The availability of further trans-sialidase sequences will ensure a better understanding of how transfer activity can be achieved and will provide the opportunity to develop highly specific, structure-based trans-sialidase inhibitors. Utilising a PCR-based approach two different trans-sialidase gene copies from T. congolense were identified, which share only 50% identity with each other, but show significant similarity with known viral, bacterial and trypanosomal sialidases and trans-sialidases. In both partial sequences most of the critical active site residues common to other trypanosomal sialidases and trans-sialidases are conserved. This is further illustrated by modelling the active site of the longer of the two partial gene sequences.
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Affiliation(s)
- Evelin Tiralongo
- Biochemisches Institut, Christian-Albrechts-Universität zu Kiel, Olshausenstrasse 40, D-24098 Kiel, Germany
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Tiralongo E, Schrader S, Lange H, Lemke H, Tiralongo J, Schauer R. Two trans-sialidase forms with different sialic acid transfer and sialidase activities from Trypanosoma congolense. J Biol Chem 2003; 278:23301-10. [PMID: 12649268 DOI: 10.1074/jbc.m212909200] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Trypanosomes express an enzyme called trans-sialidase (TS), which enables the parasites to transfer sialic acids from the environment onto trypanosomal surface molecules. Here we describe the purification and characterization of two TS forms from the African trypanosome Trypanosoma congolense. The purification of the two TS forms using a combination of anion exchange chromatography, isoelectric focusing, gel filtration, and subsequently, antibody affinity chromatography resulted, in both cases, in the isolation of a 90-kDa monomer on SDS-PAGE, which was identified as trans-sialidase using micro-sequencing. Monoclonal antibody 7/23, which bound and partially inhibited TS activity, was found in both cases to bind to a 90-kDa protein. Both TS forms possessed sialidase and transfer activity, but markedly differed in their activity ratios. The TS form with a high transfer-to-sialidase activity ratio, referred to as TS-form 1, possessed a pI of pH 4-5 and a molecular mass of 350-600 kDa. In contrast, the form with a low transfer-to-sialidase activity ratio, referred to as TS-form 2, exhibited a pI of pH 5-6.5 and a molecular mass of 130-180 kDa. Both TS forms were not significantly inhibited by known sialidase inhibitors and revealed no significant differences in donor and acceptor substrate specificities; however, TS-form 1 utilized various acceptor substrates with a higher catalytic efficiency. Interestingly, glutamic acid-alanine-rich protein, the surface glycoprotein, was co-purified with TS-form 1 suggesting an association between both proteins.
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Affiliation(s)
- Evelin Tiralongo
- Biochemisches Institut, Universität zu Kiel, Olshausenstrasse 40, Kiel 24098 Germany
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Nok AJ, Njoku GC, Balogun E. A 45-kDa midgut glycoprotein from Anopheles albimanus mosquito mediates the killing of trypanosomes. Cell Biochem Funct 2002; 20:257-62. [PMID: 12125103 DOI: 10.1002/cbf.969] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Trypanosomes do not inhabit or grow in anopheles mosquitoes, the vector for the transmission of Plasmodium parasites the causative agent for malaria. The possession of lytic factors by the anopheline mosquito was thus considered. Head and midgut sections prepared in phosphate buffered saline were tested for trypanocidal action against T. congolense. While the head section was inactive towards the trypanosomes, the midgut extract at 0.2 mg ml(-1) diminished the motility of the parasites within 2 min of incubation; killing 50% of the population after 5 min. At 0.5 mg ml(-1) of the extract, about 90% of the parasites were killed within 2 min of incubation. The midgut fraction was subjected to a purification protocol involving successive chromatography on: octyl-sepharose, reactive brown agarose and fetuin-agarose columns. A final trypanocidal active fraction (gp45), which moved homogeneously during electrophoresis as a 45-kDa protein, was recovered from the fetuin-agarose column. The protein reacted positively with thiobarbituric acid, which suggests it is a sialoglycoprotein. Desialylation of the glycoprotein nullified its trypanocidal activity on T. congolense. Similarly, when the saccharides, lactose, methyl-beta-galactoside, lactulose, methyl-umbelliferyl-beta-galactoside (MU-Gal), were included in the culture medium, they inhibited the gp45 trypanocidal activity. Asialo-fetuin and asialo-RBC also inhibited the gp45-induced killing of T. congolense cells. The potential use of anopheline 45 kDa protein in the production of transgenic tsetse flies (Glossina spp.) in the control of trypanosomiasis is discussed.
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Affiliation(s)
- Andrew J Nok
- Department of Biochemistry, Ahmadu Bello University, Zaria, Nigeria.
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Laroy W, Contreras R. Cloning of Trypanosoma cruzi trans-sialidase and expression in Pichia pastoris. Protein Expr Purif 2000; 20:389-93. [PMID: 11087678 DOI: 10.1006/prep.2000.1334] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Trypanosoma cruzi, the agent causing Chagas' disease, expresses an enzyme that transfers sialic acids among glycoproteins and glycolipids both from the host cell surface and its own surface. This enzyme, called trans-sialidase, is different from higher eukaryotic sialyltransferases in that it does not accept cytidine 5'-monophospho-N-acetylneuraminic acid as a donor substrate. Also, the common glycosyltransferase structure is not present. To study this enzyme, an active member was cloned and expressed in higher eukaryotic cells. Expression of recombinant enzyme was achieved in the methylotrophic yeast Pichia pastoris. The N-terminal fusion of a secretion signal and the C-terminal addition of an epitope tag resulted not only in high expression levels, but also enabled easy detection and purification. Using P. pastoris, we obtained about 5 mg of enzymatically active trans-sialidase per liter of induced culture medium.
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Affiliation(s)
- W Laroy
- Department of Molecular Biology, Unit of Fundamental and Applied Molecular Biology, Ghent University, B-9000 Ghent, Belgium
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31
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Frasch AC. Functional diversity in the trans-sialidase and mucin families in Trypanosoma cruzi. PARASITOLOGY TODAY (PERSONAL ED.) 2000; 16:282-6. [PMID: 10858646 DOI: 10.1016/s0169-4758(00)01698-7] [Citation(s) in RCA: 231] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Trypanosomes are unable to synthesize the monosaccharide sialic acid, but some African trypanosomes and the American Trypanosoma cruzi can incorporate sialic acid derived from the host. To do so, T. cruzi expresses a trans-sialidase, an enzyme that catalyzes the transfer of sialic acid from host glycoconjugates to mucin-like molecules located on the parasite surface membrane. The importance of the process is indicated by the fact that T. cruzi has hundreds of genes encoding trans-sialidase, trans-sialidase-like proteins and mucin core proteins. Sequence divergence of members of these families has resulted in some molecules having functions unrelated to the acquisition of sialic acid. In this article, Alberto Frasch reviews the structure and possible function of the proteins making up these families.
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Affiliation(s)
- A C Frasch
- Instituto de Investigaciones Biotecnologicas, Universidad Nacional de General San Martin, CC30, San Martin, Buenos Aires, Argentina.
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Abstract
Slalic acids are one of the most important molecules of life, since they occupy the terminal position on macromolecules and cell membranes and are involved in many biological and pathological phenomena. The structures of sialic acids, comprising a family of over 40 neuraminic acid derivatives, have been elucidated. However, many aspects of the regulation of their metabolism at the enzyme and gene levels, as well as of their functions remain mysterious. Sialic acids play a dual role, not only are they indispensable for the protection to and adaptation of life, but are also utilised by life-threatening infectious microorganisms. In this article the present state of knowledge in sialobiology, with an emphasis on my personal experience in this research area, is outlined including a discussion of necessary future work in this fascinating field of cell biology.
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Affiliation(s)
- R Schauer
- Biochemisches Institut, Christian-Albrechts-Universität, Kiel, Germany.
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Saldaña A, Sousa OE, Orn A, Harris RA. Trypanosoma rangeli sialidase: kinetics of release and antigenic characterization. Acta Trop 1998; 70:87-99. [PMID: 9707367 DOI: 10.1016/s0001-706x(98)00020-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The epimastigote stage of Trypanosoma rangeli release a sialidase with a high sialic acid hydrolysis capacity. We demonstrate that sialidase secretion is an active process that is reduced at low temperatures and in the presence of sodium azide. The enzyme is continuously released until certain maximally active concentrations are attained in the BHI culture medium when the parasite density reaches 2-3 x 10(6) cells. When introduced into culture medium already containing such enzyme levels, freshly harvested parasites do not secrete additional sialidase. These findings suggest a self-regulating mechanism and a biological role for the secreted T. rangeli sialidase. The secreted enzyme was purified to homogeneity by fractionation with ammonium sulphate and affinity chromatography. Antibodies raised against the purified molecule recognized antigens of similar molecular weights (73 kDa) in western immunoblotting analyses of T. rangeli and T. cruzi whole cell lysates. No antigenic recognition was recorded against T. cruzi active sialidase/trans-sialidase polypeptides or Clostridium perfringens and Vibrio cholerae commercial sialidases. These observations may indicate the expression of different antigenic domains in T. rangeli, T. cruzi and bacterial sialidases.
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Affiliation(s)
- A Saldaña
- Center for Research and Diagnosis of Parasitic Diseases (CIDEP), Faculty of Medicine, University of Panama
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Engstler M, Talhouk JW, Smith RE, Schauer R. Chemical synthesis of 4-trifluoromethylumbelliferyl-alpha-D-N-acetylneuraminic acid glycoside and its use for the fluorometric detection of poorly expressed natural and recombinant sialidases. Anal Biochem 1997; 250:176-80. [PMID: 9245436 DOI: 10.1006/abio.1997.2205] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
When compared to bacterial or viral sialidases, eukaryotic sialidases are expressed at lower levels and frequently show poor specific activities. The identification and characterization of sialidases from eukaryotes have been slowed down due to the limited sensitivity of available sialidase substrates. Therefore, we chemically synthesized a fluorogenic compound, 4-trifluoromethylumbelliferyl-alpha-D-N-acetylneuraminic acid (CF3MU-Neu5Ac), and tested its use as a substrate for eight different sialidases, including enzymes from viral, bacterial, and eukaryotic sources. Kinetic analysis revealed CF3MU-Neu5Ac to be a very sensitive sialidase substrate. Furthermore, this substance proves to be perfectly suitable for the in vivo examination of sialidases and for the detection of recombinant sialidase by means of expression cloning.
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Affiliation(s)
- M Engstler
- Biochemisches Institut, Christian-Albrechts-Universität, Kiel, Germany
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Abstract
Sialic acids (Sias) are terminal components of many glycoproteins and glycolipids especially of higher animals. In this exposed position they contribute significantly to the structural properties of these molecules, both in solution and on cell surfaces. Therefore, it is not surprising that Sias are important regulators of cellular and molecular interactions, in which they play a dual role. They can either mask recognition sites or serve as recognition determinants. Whereas the role of Sias in masking and in binding of pathogens to host cells has been documented over many years, their role in nonpathological cellular interaction has only been shown recently. The aim of this chapter is to summarize our knowledge about Sias in masking, for example, galactose residues, and to review the progress made during the past few years with respect to Sias as recognition determinants in the adhesion of pathogenic viruses, bacteria, and protozoa, and particularly as binding sites for endogenous cellular interaction molecules. Finally, perspectives for future research on these topics are discussed.
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Affiliation(s)
- S Kelm
- Biochemisches Institut, University of Kiel, Germany
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Schauer R, Kamerling JP. Chemistry, biochemistry and biology of sialic acids ☆. NEW COMPREHENSIVE BIOCHEMISTRY 1997; 29. [PMCID: PMC7147860 DOI: 10.1016/s0167-7306(08)60624-9] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Roland Schauer
- Biochemisches Institut, Christian-Albrechls-Universität zu Kiel, Germany
| | - Johannis P. Kamerling
- Bijuoet Center, Department of Bio-Organic Chemistry, Utrecht University, The Netherlands
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Abstract
The structure-based design of a potent inhibitor of the influenza-virus neuraminidase (sialidase) is one of the outstanding successes of rational drug design. Recent clinical trials of the drug have stimulated many companies to seek a share of the potentially huge flu market. Sialidases, however, are involved in the pathogenesis of a whole range of other diseases, so perhaps the knowledge and expertise gained from the influenza story can be used in the design of other drugs, given that they all share certain structural features.
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Affiliation(s)
- G Taylor
- School of Biology and Biochemistry, University of Bath, Claverton Down, UK.
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