1
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Dorst KM, Widmalm G. NMR chemical shift prediction and structural elucidation of linker-containing oligo- and polysaccharides using the computer program CASPER. Carbohydr Res 2023; 533:108937. [PMID: 37734222 DOI: 10.1016/j.carres.2023.108937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 09/01/2023] [Accepted: 09/01/2023] [Indexed: 09/23/2023]
Abstract
Carbohydrate structures containing alkyl groups as aglycones are useful for investigating enzyme activity and glycan-protein interactions. Moreover, linker-containing oligosaccharides with a spacer group are commonly used to print glycan microarrays or to prepare protein-conjugates as vaccine candidates. The structural accuracy of these synthesized glycans are essential for interpretation of results from biological experiments in which the compounds have been used and NMR spectroscopy can unravel and confirm their structures. An approach for efficient 1H and 13C NMR chemical shift assignments employed a parallel NOAH-10 measurement followed by NMR spin-simulation to refine the 1H NMR chemical shifts, as exemplified for a disaccharide with an azidoethyl group as an aglycone, the NMR chemical shifts of which have been used to enhance the quality of CASPER (http://www.casper.organ.su.se/casper/). The CASPER program has been further developed to aid characterization of linker-containing oligo- and polysaccharides, either by chemical shift prediction for comparison to experimental NMR data or as structural investigation of synthesized glycans based on acquired unassigned NMR data. The ability of CASPER to elucidate structures of linker-containing oligosaccharides is demonstrated and comparisons to assigned or unassigned NMR data show the utility of CASPER in supporting a proposed oligosaccharide structure. Prediction of NMR chemical shifts of an oligosaccharide, corresponding to the repeating unit of an O-antigen polysaccharide, having a linker as an aglycone and a non-natural substituent derivative thereof are presented to exemplify the diversity of structures handled. Furthermore, NMR chemical shift predictions of synthesized polysaccharides, corresponding to bacterial polysaccharides, containing a linker are described showing that in addition to oligosaccharide structures also polysaccharide structures having an aglycone spacer group can be analyzed by CASPER.
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Affiliation(s)
- Kevin M Dorst
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, S-106 91 Stockholm, Sweden
| | - Göran Widmalm
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, S-106 91 Stockholm, Sweden.
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2
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Singla A, Boucher A, Wallom KL, Lebens M, Kohler JJ, Platt FM, Yrlid U. Cholera intoxication of human enteroids reveals interplay between decoy and functional glycoconjugate ligands. Glycobiology 2023; 33:801-816. [PMID: 37622990 PMCID: PMC10629719 DOI: 10.1093/glycob/cwad069] [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: 03/10/2023] [Revised: 07/31/2023] [Accepted: 08/17/2023] [Indexed: 08/26/2023] Open
Abstract
Prior research on cholera toxin (CT) binding and intoxication has relied on human colonic cancer derived epithelial cells. While these transformed cell lines have been beneficial, they neither derive from small intestine where intoxication occurs, nor represent the diversity of small intestinal epithelial cells (SI-ECs) and variation in glycoconjugate expression among individuals. Here, we used human enteroids, derived from jejunal biopsies of multipledonors to study CT binding and intoxication of human non-transformed SI-ECs. We modulated surface expression of glycosphingolipids, glycoproteins and specific glycans to distinguish the role of each glycan/glycoconjugate. Cholera-toxin-subunit-B (CTB) mutants were generated to decipher the preference of each glycoconjugate to different binding sites and the correlation between CT binding and intoxication. Human enteroids contain trace amounts of GM1, but other glycosphingolipids may be contributing to CT intoxication. We discovered that inhibition of either fucosylation or O-glycosylation sensitize enteroids to CT-intoxication. This can either be a consequence of the removal of fucosylated "decoy-like-ligands" binding to CTB's non-canonical site and/or increase in the availability of Gal/GalNAc-terminating glycoconjugates binding to the canonical site. Furthermore, simultaneous inhibition of fucosylation and O-glycosylation increased the availability of additional Gal/GalNAc-terminating glycoconjugates but counteracted the sensitization in CT intoxication caused by inhibiting O-glycosylation because of reduction in fucose. This implies a dual role of fucose as a functional glycan and a decoy, the interplay of which influences CT binding and intoxication. Finally, while the results were similar for enteroids from different donors, they were not identical, pointing to a role for human genetic variation in determining sensitivity to CT.
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Affiliation(s)
- Akshi Singla
- Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg, Medicinaregatan 1G, 41390 Gothenburg, Sweden
- Department of Medical Chemistry and Cell Biology, Institute of Biomedicine, University of Gothenburg, Medicinaregatan 1G, 41390 Gothenburg, Sweden
| | - Andrew Boucher
- Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg, Medicinaregatan 1G, 41390 Gothenburg, Sweden
| | - Kerri-Lee Wallom
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, United Kingdom
| | - Michael Lebens
- Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg, Medicinaregatan 1G, 41390 Gothenburg, Sweden
| | - Jennifer J Kohler
- Department of Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-9185, United States
| | - Frances M Platt
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, United Kingdom
| | - Ulf Yrlid
- Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg, Medicinaregatan 1G, 41390 Gothenburg, Sweden
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3
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Ghorashi AC, Boucher A, Archer-Hartmann SA, Murray NB, Konada RSR, Zhang X, Xing C, Azadi P, Yrlid U, Kohler JJ. Fucosylated glycoproteins and fucosylated glycolipids play opposing roles in cholera intoxication. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.02.551727. [PMID: 37577488 PMCID: PMC10418270 DOI: 10.1101/2023.08.02.551727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Cholera toxin (CT) is the etiological agent of cholera. Here we report that multiple classes of fucosylated glycoconjugates function in CT binding and intoxication of intestinal epithelial cells. In Colo205 cells, knockout of B3GNT5, the enzyme required for synthesis of lacto- and neolacto-series glycosphingolipids (GSLs), reduces CT binding but sensitizes cells to intoxication. Overexpressing B3GNT5 to generate more fucosylated GSLs confers protection against intoxication, indicating that fucosylated GSLs act as decoy receptors for CT. Knockout (KO) of B3GALT5 causes increased production of fucosylated O-linked and N-linked glycoproteins, and leads to increased CT binding and intoxication. Knockout of B3GNT5 in B3GALT5 KO cells eliminates production of fucosylated GSLs but increases intoxication, identifying fucosylated glycoproteins as functional receptors for CT. These findings provide insight into molecular determinants regulating CT sensitivity of host cells.
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Affiliation(s)
- Atossa C. Ghorashi
- Department of Biochemistry, UT Southwestern Medical Center, Dallas TX 75390 USA
| | - Andrew Boucher
- Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg, 405 30 Gothenburg, Sweden
| | | | - Nathan B. Murray
- Complex Carbohydrate Research Center, The University of Georgia, 315 Riverbend Road, Athens, GA 30602, USA
| | | | - Xunzhi Zhang
- McDermott Center for Human Growth and Development, UT Southwestern Medical Center, Dallas TX 75390 USA
| | - Chao Xing
- McDermott Center for Human Growth and Development, UT Southwestern Medical Center, Dallas TX 75390 USA
- Department of Bioinformatics, UT Southwestern Medical Center, Dallas TX 75390 USA
| | - Parastoo Azadi
- Complex Carbohydrate Research Center, The University of Georgia, 315 Riverbend Road, Athens, GA 30602, USA
| | - Ulf Yrlid
- Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg, 405 30 Gothenburg, Sweden
| | - Jennifer J. Kohler
- Department of Biochemistry, UT Southwestern Medical Center, Dallas TX 75390 USA
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4
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Gerling-Driessen UIM, Hoffmann M, Schmidt S, Snyder NL, Hartmann L. Glycopolymers against pathogen infection. Chem Soc Rev 2023; 52:2617-2642. [PMID: 36820794 DOI: 10.1039/d2cs00912a] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Pathogens including viruses, bacteria, fungi, and parasites continue to shape our lives in profound ways every day. As we have learned to live in parallel with pathogens, we have gained a better understanding of the rules of engagement for how they bind, adhere, and invade host cells. One such mechanism involves the exploitation of host cell surface glycans for attachment/adhesion, one of the first steps of infection. This knowledge has led to the development of glycan-based diagnostics and therapeutics for the treatment and prevention of infection. One class of compounds that has become increasingly important are the glycopolymers. Glycopolymers are macromolecules composed of a synthetic scaffold presenting carbohydrates as side chain motifs. Glycopolymers are particularly attractive because their properties can be tuned by careful choice of the scaffold, carbohydrate/glycan, and overall presentation. In this review, we highlight studies over the past ten years that have examined the role of glycopolymers in pathogen adhesion and host cell infection, biofilm formation and removal, and drug delivery with the aim of examining the direct effects of these macromolecules on pathogen engagement. In addition, we also examine the role of glycopolymers as diagnostics for the detection and monitoring of pathogens.
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Affiliation(s)
- Ulla I M Gerling-Driessen
- Institute of Organic Chemistry and Macromolecular Chemistry, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany.
| | - Miriam Hoffmann
- Institute of Organic Chemistry and Macromolecular Chemistry, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany.
| | - Stephan Schmidt
- Institute of Organic Chemistry and Macromolecular Chemistry, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany. .,Institute for Macromolecular Chemistry, University of Freiburg, Stefan-Meier-Str. 31, 79104 Freiburg, Germany
| | - Nicole L Snyder
- Department of Chemistry, Davidson College, Davidson, North Carolina 28035, USA
| | - Laura Hartmann
- Institute of Organic Chemistry and Macromolecular Chemistry, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany.
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5
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McBerney R, Dolan JP, Cawood EE, Webb ME, Turnbull WB. Bioorthogonal, Bifunctional Linker for Engineering Synthetic Glycoproteins. JACS AU 2022; 2:2038-2047. [PMID: 36186556 PMCID: PMC9516712 DOI: 10.1021/jacsau.2c00312] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 08/14/2022] [Accepted: 08/15/2022] [Indexed: 06/16/2023]
Abstract
Post-translational glycosylation of proteins results in complex mixtures of heterogeneous protein glycoforms. Glycoproteins have many potential applications from fundamental studies of glycobiology to potential therapeutics, but generating homogeneous recombinant glycoproteins using chemical or chemoenzymatic reactions to mimic natural glycoproteins or creating homogeneous synthetic neoglycoproteins is a challenging synthetic task. In this work, we use a site-specific bioorthogonal approach to produce synthetic homogeneous glycoproteins. We develop a bifunctional, bioorthogonal linker that combines oxime ligation and strain-promoted azide-alkyne cycloaddition chemistry to functionalize reducing sugars and glycan derivatives for attachment to proteins. We demonstrate the utility of this minimal length linker by producing neoglycoprotein inhibitors of cholera toxin in which derivatives of the disaccharide lactose and GM1os pentasaccharide are attached to a nonbinding variant of the cholera toxin B-subunit that acts as a size- and valency-matched multivalent scaffold. The resulting neoglycoproteins decorated with GM1 ligands inhibit cholera toxin B-subunit adhesion with a picomolar IC50.
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6
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In silico analysis of the human milk oligosaccharide glycome reveals key enzymes of their biosynthesis. Sci Rep 2022; 12:10846. [PMID: 35760821 PMCID: PMC9237113 DOI: 10.1038/s41598-022-14260-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 06/03/2022] [Indexed: 11/09/2022] Open
Abstract
Human milk oligosaccharides (HMOs) form the third most abundant component of human milk and are known to convey several benefits to the neonate, including protection from viral and bacterial pathogens, training of the immune system, and influencing the gut microbiome. As HMO production during lactation is driven by enzymes that are common to other glycosylation processes, we adapted a model of mucin-type GalNAc-linked glycosylation enzymes to act on free lactose. We identified a subset of 11 enzyme activities that can account for 206 of 226 distinct HMOs isolated from human milk and constructed a biosynthetic reaction network that identifies 5 new core HMO structures. A comparison of monosaccharide compositions demonstrated that the model was able to discriminate between two possible groups of intermediates between major subnetworks, and to assign possible structures to several previously uncharacterised HMOs. The effect of enzyme knockouts is presented, identifying β-1,4-galactosyltransferase and β-1,3-N-acetylglucosaminyltransferase as key enzyme activities involved in the generation of the observed HMO glycosylation patterns. The model also provides a synthesis chassis for the most common HMOs found in lactating mothers.
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7
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Zalem D, Juhás M, Terrinoni M, King-Lyons N, Lebens M, Varrot A, Connell TD, Teneberg S. Characterization of the ganglioside recognition profile of Escherichia coli heat-labile enterotoxin LT-IIc. Glycobiology 2022; 32:391-403. [PMID: 34972864 PMCID: PMC9022906 DOI: 10.1093/glycob/cwab133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/23/2021] [Accepted: 12/19/2021] [Indexed: 11/14/2022] Open
Abstract
The heat-labile enterotoxins of Escherichia coli and cholera toxin of Vibrio cholerae are related in structure and function. Each of these oligomeric toxins is comprised of one A polypeptide and five B polypeptides. The B-subunits bind to gangliosides, which are followed by uptake into the intoxicated cell and activation of the host's adenylate cyclase by the A-subunits. There are two antigenically distinct groups of these toxins. Group I includes cholera toxin and type I heat-labile enterotoxin of E. coli; group II contains the type II heat-labile enterotoxins of E. coli. Three variants of type II toxins, designated LT-IIa, LT-IIb and LT-IIc have been described. Earlier studies revealed the crystalline structure of LT-IIb. Herein the carbohydrate binding specificity of LT-IIc B-subunits was investigated by glycosphingolipid binding studies on thin-layer chromatograms and in microtiter wells. Binding studies using a large variety of glycosphingolipids showed that LT-IIc binds with high affinity to gangliosides with a terminal Neu5Acα3Gal or Neu5Gcα3Gal, e.g. the gangliosides GM3, GD1a and Neu5Acα3-/Neu5Gcα3--neolactotetraosylceramide and Neu5Acα3-/Neu5Gcα3-neolactohexaosylceramide. The crystal structure of LT-IIc B-subunits alone and with bound LSTd/sialyl-lacto-N-neotetraose d pentasaccharide uncovered the molecular basis of the ganglioside recognition. These studies revealed common and unique functional structures of the type II family of heat-labile enterotoxins.
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Affiliation(s)
- Dani Zalem
- Department of Medical Biochemistry and Cell Biology, Sahlgrenska Academy, Institute of Biomedicine, University of Gothenburg, Sweden
| | - Martin Juhás
- Department of Medical Biochemistry and Cell Biology, Sahlgrenska Academy, Institute of Biomedicine, University of Gothenburg, Sweden
- Department of Pharmaceutical Chemistry and Pharmaceutical Analysis, Charles University, Faculty of Pharmacy in Hradec Králové, Akademika Heyrovského 1203, Hradec Králové 500 05, Czech Republic
| | - Manuela Terrinoni
- Department of Microbiology and Immunology, Sahlgrenska Academy, Institute of Biomedicine, University of Gothenburg, Sweden
| | - Natalie King-Lyons
- Department of Microbiology & Immunology and The Witebsky Center for Microbial Pathogenesis and Immunology, The Jacobs School of Medicine and Biomedical Sciences, The University at Buffalo, State University of New York, Buffalo, NY 14203, USA
| | - Michael Lebens
- Department of Microbiology and Immunology, Sahlgrenska Academy, Institute of Biomedicine, University of Gothenburg, Sweden
| | | | - Terry D Connell
- Department of Microbiology & Immunology and The Witebsky Center for Microbial Pathogenesis and Immunology, The Jacobs School of Medicine and Biomedical Sciences, The University at Buffalo, State University of New York, Buffalo, NY 14203, USA
| | - Susann Teneberg
- Department of Medical Biochemistry and Cell Biology, Sahlgrenska Academy, Institute of Biomedicine, University of Gothenburg, Sweden
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8
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Glycan-mediated molecular interactions in bacterial pathogenesis. Trends Microbiol 2022; 30:254-267. [PMID: 34274195 PMCID: PMC8758796 DOI: 10.1016/j.tim.2021.06.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 06/10/2021] [Accepted: 06/22/2021] [Indexed: 02/06/2023]
Abstract
Glycans are expressed on the surface of nearly all host and bacterial cells. Not surprisingly, glycan-mediated molecular interactions play a vital role in bacterial pathogenesis and host responses against pathogens. Glycan-mediated host-pathogen interactions can benefit the pathogen, host, or both. Here, we discuss (i) bacterial glycans that play a critical role in bacterial colonization and/or immune evasion, (ii) host glycans that are utilized by bacteria for pathogenesis, and (iii) bacterial and host glycans involved in immune responses against pathogens. We further discuss (iv) opportunities and challenges for transforming these research findings into more effective antibacterial strategies, and (v) technological advances in glycoscience that have helped to accelerate progress in research. These studies collectively offer valuable insights into new perspectives on antibacterial strategies that may effectively tackle the drug-resistant pathogens that are rapidly spreading globally.
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9
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Ren LL, Zhou JY, Liang SJ, Wang XQ. Impaired intestinal stem cell activity in ETEC infection: enterotoxins, cyclic nucleotides, and Wnt signaling. Arch Toxicol 2022; 96:1213-1225. [PMID: 35226135 DOI: 10.1007/s00204-021-03213-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 12/21/2021] [Indexed: 12/25/2022]
Abstract
Enterotoxigenic Escherichia coli (ETEC) in humans and animals colonizes the intestine and thereafter secrets heat-stable enterotoxin (ST) with or without heat-labile enterotoxin (LT), which triggers massive fluid and electrolyte secretion into the gut lumen. The crosstalk between the cyclic nucleotide-dependent protein kinase/cystic fibrosis transmembrane conductance regulator (cAMP or cGMP/CFTR) pathway involved in ETEC-induced diarrhea channels, and the canonical Wnt/β-catenin signaling pathway leads to changes in intestinal stem cell (ISC) fates, which are strongly associated with developmental disorders caused by diarrhea. We review how alterations in enterotoxin-activated ion channel pathways and the canonical Wnt/β-catenin signaling pathway can explain inhibited intestinal epithelial activity, characterize alterations in the crosstalk of cyclic nucleotides, and predict harmful effects on ISCs in targeted therapy. Besides, we discuss current deficits in the understanding of enterotoxin-intestinal epithelial cell activity relationships that should be considered when interpreting sequelae of diarrhea.
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Affiliation(s)
- Lu-Lu Ren
- College of Animal Science, South China Agricultural University/Guangdong Laboratory for Lingnan Modern Agriculture/Guangdong Provincial Key Laboratory of Animal Nutrition Control/National Engineering Research Center for Breeding Swine Industry, Guangzhou, 510642, China
| | - Jia-Yi Zhou
- College of Animal Science, South China Agricultural University/Guangdong Laboratory for Lingnan Modern Agriculture/Guangdong Provincial Key Laboratory of Animal Nutrition Control/National Engineering Research Center for Breeding Swine Industry, Guangzhou, 510642, China
| | - Shao-Jie Liang
- College of Animal Science, South China Agricultural University/Guangdong Laboratory for Lingnan Modern Agriculture/Guangdong Provincial Key Laboratory of Animal Nutrition Control/National Engineering Research Center for Breeding Swine Industry, Guangzhou, 510642, China
| | - Xiu-Qi Wang
- College of Animal Science, South China Agricultural University/Guangdong Laboratory for Lingnan Modern Agriculture/Guangdong Provincial Key Laboratory of Animal Nutrition Control/National Engineering Research Center for Breeding Swine Industry, Guangzhou, 510642, China.
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10
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Wu HJ, Singla A, Weatherston JD. Nanocube-Based Fluidic Glycan Array. Methods Mol Biol 2022; 2460:45-63. [PMID: 34972930 DOI: 10.1007/978-1-0716-2148-6_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The nature of cell membrane fluidity permits glycans, which are attached to membrane proteins and lipids, to freely diffuse on cell surfaces. Through such two-dimensional motion, some weakly binding glycans can participate in lectin binding processes, eventually changing lectin binding behaviors. This chapter discusses a plasmonic nanocube sensor that allows users to detect lectin binding kinetics in a cell membrane mimicking environment. This assay only requires standard laboratory spectrometers, including microplate readers. We describe the basics of the technology in detail, including sensor fabrication, sensor calibration, data processing, a general protocol for detecting lectin-glycan interactions, and a troubleshooting guide.
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Affiliation(s)
- Hung-Jen Wu
- Department of Chemical Engineering, Texas A&M University, College Station, TX, USA.
| | - Akshi Singla
- Department of Chemical Engineering, Texas A&M University, College Station, TX, USA
| | - Joshua D Weatherston
- Department of Chemical Engineering, Texas A&M University, College Station, TX, USA
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11
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Richards SJ, Gibson MI. Toward Glycomaterials with Selectivity as Well as Affinity. JACS AU 2021; 1:2089-2099. [PMID: 34984416 PMCID: PMC8717392 DOI: 10.1021/jacsau.1c00352] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Indexed: 05/08/2023]
Abstract
Multivalent glycosylated materials (polymers, surfaces, and particles) often show high affinity toward carbohydrate binding proteins (e.g., lectins) due to the nonlinear enhancement from the cluster glycoside effect. This affinity gain has potential in applications from diagnostics, biosensors, and targeted delivery to anti-infectives and in an understanding of basic glycobiology. This perspective highlights the question of selectivity, which is less often addressed due to the reductionist nature of glycomaterials and the promiscuity of many lectins. The use of macromolecular features, including architecture, heterogeneous ligand display, and the installation of non-natural glycans, to address this challenge is discussed, and examples of selectivity gains are given.
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Affiliation(s)
| | - Matthew I. Gibson
- Department
of Chemistry, University of Warwick, Coventry CV4 7AL, U.K.
- Warwick
Medical School, University of Warwick, Coventry CV4 7AL, U.K.
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12
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Verkhnyatskaya SA, Kong C, Klostermann CE, Schols HA, de Vos P, Walvoort MTC. Digestion, fermentation, and pathogen anti-adhesive properties of the hMO-mimic di-fucosyl-β-cyclodextrin. Food Funct 2021; 12:5018-5026. [PMID: 33954318 PMCID: PMC8185958 DOI: 10.1039/d1fo00830g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 04/23/2021] [Indexed: 12/28/2022]
Abstract
Human milk is widely acknowledged as the best food for infants, and that is not just because of nutritional features. Human milk also contains a plethora of bioactive molecules, including a large set of human milk oligosaccharides (hMOs). Especially fucosylated hMOs have received attention for their anti-adhesive effects on pathogens, preventing attachment to the intestine and infection. Because hMOs are generally challenging to produce in sufficient quantities to study and ultimately apply in (medical) infant formula, novel compounds that are inspired by hMO structures (so-called "mimics") are interesting compounds to produce and evaluate for their biological effects. Here we present our thorough study into the digestion, fermentation and anti-adhesive capacity of the novel compound di-fucosyl-β-cyclodextrin (DFβCD), which was inspired by the molecular structures of hMOs. We establish that DFβCD is not digested by α-amylase and also resistant to fermentation by microbial enzymes from a 9 month-old infant inoculum. In addition, we reveal that DFβCD blocks adhesion of enterotoxigenic E. coli (ETEC) to Caco-2 cells, especially when DFβCD is pre-incubated with ETEC prior to addition to the Caco-2 cells. This suggests that DFβCD functions through a decoy effect. We expect that our results inspire the generation and biological evaluation of other fucosylated hMOs and mimics, to obtain a comprehensive overview of the anti-adhesive power of fucosylated glycans.
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Affiliation(s)
| | - Chunli Kong
- Department of Pathology and Medical Biology, University Medical Center Groningen, Groningen, the Netherlands
| | - Cynthia E Klostermann
- Biobased Chemistry and Technology, Wageningen University & Research, Wageningen, the Netherlands
| | - Henk A Schols
- Laboratory of Food Chemistry, Wageningen University & Research, Wageningen, the Netherlands
| | - Paul de Vos
- Department of Pathology and Medical Biology, University Medical Center Groningen, Groningen, the Netherlands
| | - Marthe T C Walvoort
- Stratingh Institute for Chemistry, University of Groningen, Groningen, the Netherlands.
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13
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Huang YF, Aoki K, Akase S, Ishihara M, Liu YS, Yang G, Kizuka Y, Mizumoto S, Tiemeyer M, Gao XD, Aoki-Kinoshita KF, Fujita M. Global mapping of glycosylation pathways in human-derived cells. Dev Cell 2021; 56:1195-1209.e7. [PMID: 33730547 PMCID: PMC8086148 DOI: 10.1016/j.devcel.2021.02.023] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Revised: 12/15/2020] [Accepted: 02/12/2021] [Indexed: 01/02/2023]
Abstract
Glycans are one of the fundamental classes of macromolecules and are involved in a broad range of biological phenomena. A large variety of glycan structures can be synthesized depending on tissue or cell types and environmental changes. Here, we developed a comprehensive glycosylation mapping tool, termed GlycoMaple, to visualize and estimate glycan structures based on gene expression. We informatically selected 950 genes involved in glycosylation and its regulation. Expression profiles of these genes were mapped onto global glycan metabolic pathways to predict glycan structures, which were confirmed using glycomic analyses. Based on the predictions of N-glycan processing, we constructed 40 knockout HEK293 cell lines and analyzed the effects of gene knockout on glycan structures. Finally, the glycan structures of 64 cell lines, 37 tissues, and primary colon tumor tissues were estimated and compared using publicly available databases. Our systematic approach can accelerate glycan analyses and engineering in mammalian cells.
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Affiliation(s)
- Yi-Fan Huang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Kazuhiro Aoki
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
| | - Sachiko Akase
- Graduate School of Engineering, Soka University, Hachioji, Tokyo 192-8577, Japan
| | - Mayumi Ishihara
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
| | - Yi-Shi Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Ganglong Yang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Yasuhiko Kizuka
- Center for Highly Advanced Integration of Nano and Life Sciences (G-CHAIN), Gifu University, Gifu 501-1193, Japan; Institute for Glyco-core Research (iGCORE), Gifu University, Gifu 501-1193, Japan
| | - Shuji Mizumoto
- Department of Pathobiochemistry, Faculty of Pharmacy, Meijo University, Nagoya, Aichi 468-8503, Japan
| | - Michael Tiemeyer
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
| | - Xiao-Dong Gao
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Kiyoko F Aoki-Kinoshita
- Graduate School of Engineering, Soka University, Hachioji, Tokyo 192-8577, Japan; Glycan & Life System Integration Center (GaLSIC), Faculty of Science and Engineering, Soka University, Hachioji, Tokyo 192-8577, Japan.
| | - Morihisa Fujita
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu 214122, China.
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14
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Deusenbery C, Wang Y, Shukla A. Recent Innovations in Bacterial Infection Detection and Treatment. ACS Infect Dis 2021; 7:695-720. [PMID: 33733747 DOI: 10.1021/acsinfecdis.0c00890] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Bacterial infections are a major threat to human health, exacerbated by increasing antibiotic resistance. These infections can result in tremendous morbidity and mortality, emphasizing the need to identify and treat pathogenic bacteria quickly and effectively. Recent developments in detection methods have focused on electrochemical, optical, and mass-based biosensors. Advances in these systems include implementing multifunctional materials, microfluidic sampling, and portable data-processing to improve sensitivity, specificity, and ease of operation. Concurrently, advances in antibacterial treatment have largely focused on targeted and responsive delivery for both antibiotics and antibiotic alternatives. Antibiotic alternatives described here include repurposed drugs, antimicrobial peptides and polymers, nucleic acids, small molecules, living systems, and bacteriophages. Finally, closed-loop therapies are combining advances in the fields of both detection and treatment. This review provides a comprehensive summary of the current trends in detection and treatment systems for bacterial infections.
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Affiliation(s)
- Carly Deusenbery
- School of Engineering, Center for Biomedical Engineering, Institute for Molecular and Nanoscale Innovation, Brown University, Providence, Rhode Island 02912, United States
| | - Yingying Wang
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Anita Shukla
- School of Engineering, Center for Biomedical Engineering, Institute for Molecular and Nanoscale Innovation, Brown University, Providence, Rhode Island 02912, United States
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15
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Asadpoor M, Ithakisiou GN, Henricks PAJ, Pieters R, Folkerts G, Braber S. Non-Digestible Oligosaccharides and Short Chain Fatty Acids as Therapeutic Targets against Enterotoxin-Producing Bacteria and Their Toxins. Toxins (Basel) 2021; 13:175. [PMID: 33668708 PMCID: PMC7996226 DOI: 10.3390/toxins13030175] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 02/08/2021] [Accepted: 02/17/2021] [Indexed: 02/07/2023] Open
Abstract
Enterotoxin-producing bacteria (EPB) have developed multiple mechanisms to disrupt gut homeostasis, and provoke various pathologies. A major part of bacterial cytotoxicity is attributed to the secretion of virulence factors, including enterotoxins. Depending on their structure and mode of action, enterotoxins intrude the intestinal epithelium causing long-term consequences such as hemorrhagic colitis. Multiple non-digestible oligosaccharides (NDOs), and short chain fatty acids (SCFA), as their metabolites produced by the gut microbiota, interact with enteropathogens and their toxins, which may result in the inhibition of the bacterial pathogenicity. NDOs characterized by diverse structural characteristics, block the pathogenicity of EPB either directly, by inhibiting bacterial adherence and growth, or biofilm formation or indirectly, by promoting gut microbiota. Apart from these abilities, NDOs and SCFA can interact with enterotoxins and reduce their cytotoxicity. These anti-virulent effects mostly rely on their ability to mimic the structure of toxin receptors and thus inhibiting toxin adherence to host cells. This review focuses on the strategies of EPB and related enterotoxins to impair host cell immunity, discusses the anti-pathogenic properties of NDOs and SCFA on EPB functions and provides insight into the potential use of NDOs and SCFA as effective agents to fight against enterotoxins.
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Affiliation(s)
- Mostafa Asadpoor
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands; (M.A.); (G.-N.I.); (P.A.J.H.); (G.F.)
| | - Georgia-Nefeli Ithakisiou
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands; (M.A.); (G.-N.I.); (P.A.J.H.); (G.F.)
| | - Paul A. J. Henricks
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands; (M.A.); (G.-N.I.); (P.A.J.H.); (G.F.)
| | - Roland Pieters
- Division of Medicinal Chemistry and Chemical Biology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands;
| | - Gert Folkerts
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands; (M.A.); (G.-N.I.); (P.A.J.H.); (G.F.)
| | - Saskia Braber
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands; (M.A.); (G.-N.I.); (P.A.J.H.); (G.F.)
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16
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Garber JM, Hennet T, Szymanski CM. Significance of fucose in intestinal health and disease. Mol Microbiol 2021; 115:1086-1093. [PMID: 33434389 DOI: 10.1111/mmi.14681] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 12/30/2020] [Accepted: 01/08/2021] [Indexed: 12/14/2022]
Abstract
The deoxyhexose sugar L-fucose is important for many biological processes within the human body and the associated microbiota. This carbohydrate is abundant in host gut mucosal surfaces, numerous microbial cell surface structures, and some dietary carbohydrates. Fucosylated oligosaccharides facilitate the establishment of a healthy microbiota and provide protection from infection. However, there are instances where pathogens can also exploit these fucosylated structures to cause infection. Furthermore, deficiencies in host fucosylation are associated with specific disease outcomes. This review focuses on our current understanding of the impact of fucosylation within the mucosal environment of the gastrointestinal tract with a specific emphasis on the mediatory effects in host-microbe interactions.
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Affiliation(s)
- Jolene M Garber
- Complex Carbohydrate Research Center and Department of Microbiology, University of Georgia, Athens, GA, USA
| | - Thierry Hennet
- Institute of Physiology, University of Zurich, Zurich, Switzerland
| | - Christine M Szymanski
- Complex Carbohydrate Research Center and Department of Microbiology, University of Georgia, Athens, GA, USA
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17
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Awuor SO, Omwenga EO, Daud II. Geographical distribution and antibiotics susceptibility patterns of toxigenic Vibrio cholerae isolates from Kisumu County, Kenya. Afr J Prim Health Care Fam Med 2020; 12:e1-e6. [PMID: 33354982 PMCID: PMC7736671 DOI: 10.4102/phcfm.v12i1.2264] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 03/23/2020] [Accepted: 03/24/2020] [Indexed: 11/24/2022] Open
Abstract
Background Multiple drug resistance has become a major threat to the treatment of cholera. Recent studies in Kenya have described the epidemiology, especially the risk factors, of cholera; however, there is little information on the phenotypic and drug susceptibility patterns of Vibrio cholerae (V. cholerae) in outbreaks that in the recent past have occurred in western Kenya. Aim To characterise and determine the antibiotics’ susceptibility profiling of toxigenic V. cholerae isolates from Kisumu County. Setting The project was conducted in Kisumu County, Kenya. Methods A total of 119 V. cholerae O1, biotype El Tor, isolates collected during 2017 cholera outbreak in Kisumu County were used for this study. The samples were cultured on thiosulphate-citrate-bile salts sucrose (TCBS) agar and biochemical tests were carried out using standard procedures. Susceptibility tests were conducted by using various conventional antibiotics against standard procedures. Results Of the 119 isolates, 101 were confirmed to be V. cholerae belonging to serotypes Inaba and Ogawa, with Inaba being the predominant serotype (73.95%). The isolates were susceptible to ciprofloxacin (100%), ofloxacin (100%), gentamycin (100%), doxycycline (99%), ceftriaxone (99%) and streptomycin (96.04%) antimicrobials, and resistant to erythromycin (53.47%), amoxicillin (64.4%), nalidixic acid (83.2%) and ampicillin (89.11%), with high resistance to cotrimoxazole (99%) and tetracycline (97%). Conclusion Vibrio cholerae was resistant to multiple antibiotics, including those commonly used in the management of cholera. Taken together, there is a need to carry out regular surveillance on antimicrobial drug resistance during outbreaks.
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Affiliation(s)
- Silas O Awuor
- Department of Health, School of Health Sciences, Kisii University, Kisii.
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18
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Youn G, Cervin J, Yu X, Bhatia SR, Yrlid U, Sampson NS. Targeting Multiple Binding Sites on Cholera Toxin B with Glycomimetic Polymers Promotes the Formation of Protein-Polymer Aggregates. Biomacromolecules 2020; 21:4878-4887. [PMID: 32960582 DOI: 10.1021/acs.biomac.0c01122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The canonical binding site on the B subunit of cholera toxin (CTB) binds to GM1 gangliosides on host cells. However, the recently discovered noncanonical binding site on CTB with affinity for fucosylated molecules has raised the possibility that both sites can be involved in initiating intoxication. Previously, we showed that blocking CTB binding to human and murine small intestine epithelial cells can be increased by simultaneously targeting both binding sites with multivalent norbornene-based glycopolymers [ACS Infect. Dis. 2020, 6, 5, 1192-1203]. However, the mechanistic origin of the increased blocking efficacy was unclear. Herein, we observed that mixing CTB pentamers and glycopolymers that display fucose and galactose sugars results in the formation of large aggregates, which further inhibits binding of CTB to human granulocytes. Dynamic light scattering analysis, small-angle X-ray scattering analysis, transmission electron microscopy, and turbidimetric assays revealed that the facial directionality of CTB promotes interchain cross-linking, which in turn leads to self-assembly of protein-polymer networks. This cross-linking-induced self-assembly occurs only when the glycopolymer system contains both galactose and fucose. In an assay of the glycopolymer's ability to block CTB binding to human granulocytes, we observed a direct correlation between IC50 and self-assembly size. The aggregation mechanism of inhibition proposed herein has potential utility for the development of low-cost macromolecular clinical therapeutics for cholera that do not have exotic architectures and do not require complex synthetic sequences.
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Affiliation(s)
- Gyusaang Youn
- Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-6500, United States
| | - Jakob Cervin
- Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg, 405 30 Gothenburg, Sweden
| | - Xiaoxi Yu
- Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-6500, United States
| | - Surita R Bhatia
- Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-6500, United States
| | - Ulf Yrlid
- Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg, 405 30 Gothenburg, Sweden
| | - Nicole S Sampson
- Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-6500, United States
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19
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Roy R, Ghosh B, Kar P. Investigating Conformational Dynamics of Lewis Y Oligosaccharides and Elucidating Blood Group Dependency of Cholera Using Molecular Dynamics. ACS OMEGA 2020; 5:3932-3942. [PMID: 32149220 PMCID: PMC7057322 DOI: 10.1021/acsomega.9b03398] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Accepted: 02/11/2020] [Indexed: 05/08/2023]
Abstract
Cholera is caused by Vibrio cholerae and is an example of a blood-group-dependent disease. Recent studies suggest that the receptor-binding B subunit of the cholera toxin (CT) binds histo-blood group antigens at a secondary binding site. Herein, we studied the conformational dynamics of Lewis Y (LeY) oligosaccharides, H-tetrasaccharides and A-pentasaccharides, in aqueous solution by conducting accelerated molecular dynamics (aMD) simulations. The flexible nature of both oligosaccharides was displayed in aMD simulations. Furthermore, aMD simulations revealed that for both oligosaccharides in the free form, 4C1 and 1C4 puckers were sampled for all but GalNAc monosaccharides, while either the 4C1 (GlcNAc, Gal, GalNAc) or 1C4 (Fuc2, Fuc3) pucker was sampled in the CT-bound forms. In aMD, the complete transition from the 4C1 to 1C4 pucker was sampled for GlcNAc and Gal in both oligosaccharides. Further, we have observed a transition from the open to closed conformer in the case of A-pentasaccharide, while H-tetrasaccharide remains in the open conformation throughout the simulation. Both oligosaccharides adopted an open conformation in the CT binding site. Moreover, we have investigated the molecular basis of recognition of LeY oligosaccharides by the B subunit of the cholera toxin of classical and El Tor biotypes using the molecular mechanics generalized Born surface area (MM/GBSA) scheme. The O blood group determinant, H-tetrasaccharide, exhibits a stronger affinity to both biotypes compared to the A blood group determinant, A-pentasaccharide, which agrees with the experimental data. The difference in binding free energy between O and A blood group determinants mainly arises due to the increased entropic cost and desolvation energy in the case of A-pentasaccharide compared to that of H-tetrasaccharide. Our study also reveals that the terminal Fuc3 contributes most to the binding free energy compared to other carbohydrate residues as it forms multiple hydrogen bonds with CT. Overall, our study might help in designing glycomimetic drugs targeting the cholera toxin.
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Affiliation(s)
- Rajarshi Roy
- Discipline
of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Khandwa Road, Indore 453552, India
| | - Biplab Ghosh
- High
Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India
| | - Parimal Kar
- Discipline
of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Khandwa Road, Indore 453552, India
- E-mail: . Phone: +91 731 2438700 (ext. 550)
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20
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The gastrointestinal pathogen Campylobacter jejuni metabolizes sugars with potential help from commensal Bacteroides vulgatus. Commun Biol 2020; 3:2. [PMID: 31925306 PMCID: PMC6946681 DOI: 10.1038/s42003-019-0727-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Accepted: 12/04/2019] [Indexed: 01/07/2023] Open
Abstract
Although the gastrointestinal pathogen Campylobacter jejuni was considered asaccharolytic, >50% of sequenced isolates possess an operon for L-fucose utilization. In C. jejuni NCTC11168, this pathway confers L-fucose chemotaxis and competitive colonization advantages in the piglet diarrhea model, but the catabolic steps remain unknown. Here we solved the putative dehydrogenase structure, resembling FabG of Burkholderia multivorans. The C. jejuni enzyme, FucX, reduces L-fucose and D-arabinose in vitro and both sugars are catabolized by fuc-operon encoded enzymes. This enzyme alone confers chemotaxis to both sugars in a non-carbohydrate-utilizing C. jejuni strain. Although C. jejuni lacks fucosidases, the organism exhibits enhanced growth in vitro when co-cultured with Bacteroides vulgatus, suggesting scavenging may occur. Yet, when excess amino acids are available, C. jejuni prefers them to carbohydrates, indicating a metabolic hierarchy exists. Overall this study increases understanding of nutrient metabolism by this pathogen, and identifies interactions with other gut microbes.
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21
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Haksar D, Quarles van Ufford L, Pieters RJ. A hybrid polymer to target blood group dependence of cholera toxin. Org Biomol Chem 2020; 18:52-55. [DOI: 10.1039/c9ob02369k] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
New hybrid glycopolymers were synthesized that contain two epitopes blocking GM1- and fucose-based intoxication modes of the cholera toxin.
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Affiliation(s)
- Diksha Haksar
- Department of Chemical Biology & Drug Discovery
- Utrecht Institute for Pharmaceutical Sciences
- Utrecht University
- 3508 TB Utrecht
- The Netherlands
| | - Linda Quarles van Ufford
- Department of Chemical Biology & Drug Discovery
- Utrecht Institute for Pharmaceutical Sciences
- Utrecht University
- 3508 TB Utrecht
- The Netherlands
| | - Roland J. Pieters
- Department of Chemical Biology & Drug Discovery
- Utrecht Institute for Pharmaceutical Sciences
- Utrecht University
- 3508 TB Utrecht
- The Netherlands
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22
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Choi HK, Lee D, Singla A, Kwon JSI, Wu HJ. The influence of heteromultivalency on lectin-glycan binding behavior. Glycobiology 2019; 29:397-408. [PMID: 30824941 DOI: 10.1093/glycob/cwz010] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 02/14/2019] [Accepted: 02/19/2019] [Indexed: 02/06/2023] Open
Abstract
We recently discovered that the nature of lectin multivalency and glycolipid diffusion on cell membranes could lead to the heteromultivalent binding (i.e., a single lectin simultaneously binding to different types of glycolipid ligands). This heteromultivalent binding may even govern the lectin-glycan recognition process. To investigate this, we developed a kinetic Monte Carlo simulation, which only considers the fundamental physics/chemistry principles, to model the process of lectin binding to glycans on cell surfaces. We found that the high-affinity glycan ligands could facilitate lectin binding to other low-affinity glycan ligands, even though these low-affinity ligands are barely detectable in microarrays with immobilized glycan ligands. Such heteromultivalent binding processes significantly change lectin binding behaviors. We hypothesize that living organisms probably utilize this mechanism to regulate the downstream lectin functions. Our finding not only offers a mechanism to describe the concept that lectins are pattern recognition molecules, but also suggests that the two overlooked parameters, surface diffusion of glycan ligand and lectin binding kinetics, can play important roles in glycobiology processes. In this paper, we identified the critical parameters that influence the heteromultivalent binding process. We also discussed how our discovery can impact the current lectin-glycan analysis.
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Affiliation(s)
- Hyun-Kyu Choi
- Department of Chemical Engineering, Texas A&M University, 3122 TAMU, College Station, TX USA
| | - Dongheon Lee
- Department of Chemical Engineering, Texas A&M University, 3122 TAMU, College Station, TX USA
| | - Akshi Singla
- Department of Chemical Engineering, Texas A&M University, 3122 TAMU, College Station, TX USA
| | - Joseph Sang-Il Kwon
- Department of Chemical Engineering, Texas A&M University, 3122 TAMU, College Station, TX USA
| | - Hung-Jen Wu
- Department of Chemical Engineering, Texas A&M University, 3122 TAMU, College Station, TX USA
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23
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Lectin antagonists in infection, immunity, and inflammation. Curr Opin Chem Biol 2019; 53:51-67. [DOI: 10.1016/j.cbpa.2019.07.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 07/12/2019] [Accepted: 07/18/2019] [Indexed: 12/12/2022]
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24
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Cytoplasmic glycoengineering enables biosynthesis of nanoscale glycoprotein assemblies. Nat Commun 2019; 10:5403. [PMID: 31776333 PMCID: PMC6881330 DOI: 10.1038/s41467-019-13283-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 10/29/2019] [Indexed: 12/19/2022] Open
Abstract
Glycosylation of proteins profoundly impacts their physical and biological properties. Yet our ability to engineer novel glycoprotein structures remains limited. Established bacterial glycoengineering platforms require secretion of the acceptor protein to the periplasmic space and preassembly of the oligosaccharide substrate as a lipid-linked precursor, limiting access to protein and glycan substrates respectively. Here, we circumvent these bottlenecks by developing a facile glycoengineering platform that operates in the bacterial cytoplasm. The Glycoli platform leverages a recently discovered site-specific polypeptide glycosyltransferase together with variable glycosyltransferase modules to synthesize defined glycans, of bacterial or mammalian origin, directly onto recombinant proteins in the E. coli cytoplasm. We exploit the cytoplasmic localization of this glycoengineering platform to generate a variety of multivalent glycostructures, including self-assembling nanomaterials bearing hundreds of copies of the glycan epitope. This work establishes cytoplasmic glycoengineering as a powerful platform for producing glycoprotein structures with diverse future biomedical applications. Established bacterial glycoengineering platforms limit access to protein and glycan substrates. Here the authors design a cytoplasmic protein glycosylation system, Glycoli, to generate a variety of multivalent glycostructures.
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25
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Crystal structures of cholera toxin in complex with fucosylated receptors point to importance of secondary binding site. Sci Rep 2019; 9:12243. [PMID: 31439922 PMCID: PMC6706398 DOI: 10.1038/s41598-019-48579-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 08/02/2019] [Indexed: 01/15/2023] Open
Abstract
Cholera is a life-threatening diarrhoeal disease caused by the human pathogen Vibrio cholerae. Infection occurs after ingestion of the bacteria, which colonize the human small intestine and secrete their major virulence factor – the cholera toxin (CT). The GM1 ganglioside is considered the primary receptor of the CT, but recent studies suggest that also fucosylated receptors such as histo-blood group antigens are important for cellular uptake and toxicity. Recently, a special focus has been on the histo-blood group antigen Lewisx (Lex), however, where and how the CT binds to Lex remains unclear. Here we report the high-resolution crystal structure (1.5 Å) of the receptor-binding B-subunits of the CT bound to the Lex trisaccharide, and complementary quantitative binding data for CT holotoxins. Lex, and also l-fucose alone, bind to the secondary binding site of the toxin, distinct from the GM1 binding site. In contrast, fucosyl-GM1 mainly binds to the primary binding site due to high-affinity interactions of its GM1 core. Lex is the first histo-blood group antigen of non-secretor phenotype structurally investigated in complex with CT. Together with the quantitative binding data, this allows unique insight into why individuals with non-secretor phenotype are more prone to severe cholera than so-called ‘secretors’.
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26
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Bioisosteres of Carbohydrate Functional Groups in Glycomimetic Design. Biomimetics (Basel) 2019; 4:biomimetics4030053. [PMID: 31357673 PMCID: PMC6784292 DOI: 10.3390/biomimetics4030053] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 07/25/2019] [Accepted: 07/26/2019] [Indexed: 02/07/2023] Open
Abstract
The aberrant presentation of carbohydrates has been linked to a number of diseases, such as cancer metastasis and immune dysregulation. These altered glycan structures represent a target for novel therapies by modulating their associated interactions with neighboring cells and molecules. Although these interactions are highly specific, native carbohydrates are characterized by very low affinities and inherently poor pharmacokinetic properties. Glycomimetic compounds, which mimic the structure and function of native glycans, have been successful in producing molecules with improved pharmacokinetic (PK) and pharmacodynamic (PD) features. Several strategies have been developed for glycomimetic design such as ligand pre-organization or reducing polar surface area. A related approach to developing glycomimetics relies on the bioisosteric replacement of carbohydrate functional groups. These changes can offer improvements to both binding affinity (e.g., reduced desolvation costs, enhanced metal chelation) and pharmacokinetic parameters (e.g., improved oral bioavailability). Several examples of bioisosteric modifications to carbohydrates have been reported; this review aims to consolidate them and presents different possibilities for enhancing core interactions in glycomimetics.
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27
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Verkhnyatskaya SA, de Vries AH, Douma‐de Vries E, Sneep RJL, Walvoort MTC. Direct and Regioselective Di-α-fucosylation on the Secondary Rim of β-Cyclodextrin. Chemistry 2019; 25:6722-6727. [PMID: 30801812 PMCID: PMC6563713 DOI: 10.1002/chem.201806090] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 02/15/2019] [Indexed: 01/01/2023]
Abstract
A straightforward glycosylation method is described to regio- and stereoselectively introduce two α-l-fucose moieties directly to the secondary rim of β-cyclodextrin. Using NMR and MS fragmentation studies, the nonasaccharide structure was determined, which was also visualized using molecular dynamics simulations. The reported glycosylation method proved to be robust on gram-scale, and may be generally applied to directly glycosylate β-cyclodextrins to make well-defined multivalent glycoclusters.
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Affiliation(s)
- Stella A. Verkhnyatskaya
- Stratingh Institute for ChemistryUniversity of GroningenNijenborgh 79747 AGGroningenThe Netherlands
| | - Alex H. de Vries
- Groningen Biomolecular Sciences and Biotechnology InstituteUniversity of GroningenNijenborgh 79747 AGGroningenThe Netherlands
| | - Elmatine Douma‐de Vries
- Stratingh Institute for ChemistryUniversity of GroningenNijenborgh 79747 AGGroningenThe Netherlands
| | - Renze J. L. Sneep
- Stratingh Institute for ChemistryUniversity of GroningenNijenborgh 79747 AGGroningenThe Netherlands
| | - Marthe T. C. Walvoort
- Stratingh Institute for ChemistryUniversity of GroningenNijenborgh 79747 AGGroningenThe Netherlands
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28
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Sethi A, Wands AM, Mettlen M, Krishnamurthy S, Wu H, Kohler JJ. Cell type and receptor identity regulate cholera toxin subunit B (CTB) internalization. Interface Focus 2019; 9:20180076. [PMID: 30842875 PMCID: PMC6388018 DOI: 10.1098/rsfs.2018.0076] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/09/2019] [Indexed: 12/21/2022] Open
Abstract
Cholera toxin (CT) is a secreted bacterial toxin that binds to glycoconjugate receptors on the surface of mammalian cells, enters mammalian cells through endocytic mechanisms and intoxicates mammalian cells by activating cytosolic adenylate cyclase. CT recognizes cell surface receptors through its B subunit (CTB). While the ganglioside GM1 has been historically described as the sole receptor, CTB is also capable of binding to fucosylated glycoconjugates, and fucosylated molecules have been shown to play a functional role in host cell intoxication by CT. Here, we use colonic epithelial and respiratory epithelial cell lines to examine how two types of CT receptors-gangliosides and fucosylated glycoconjugates-contribute to CTB internalization. We show that fucosylated glycoconjugates contribute to CTB binding to and internalization into host cells, even when the ganglioside GM1 is present. The contributions of the two classes of receptors to CTB internalization depend on cell type. Additionally, in a cell line that harbours both classes of receptors, gangliosides dictate the efficiency of CTB internalization. Together, the results lend support to the idea that fucosylated glycoconjugates play a functional role in CTB internalization, and suggest that CT internalization depends on both receptor identity and cell type.
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Affiliation(s)
- Anirudh Sethi
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Amberlyn M Wands
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Marcel Mettlen
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Soumya Krishnamurthy
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Han Wu
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Jennifer J Kohler
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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29
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Bücher KS, Konietzny PB, Snyder NL, Hartmann L. Heteromultivalent Glycooligomers as Mimetics of Blood Group Antigens. Chemistry 2019; 25:3301-3309. [PMID: 30431195 DOI: 10.1002/chem.201804505] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 10/26/2018] [Indexed: 12/19/2022]
Abstract
Precision glycomacromolecules have proven to be important tools for the investigation of multivalent carbohydrate-lectin interactions by presenting multiple glycan epitopes on a highly-defined synthetic scaffold. Herein, we present a new strategy for the versatile assembly of heteromultivalent glycomacromolecules that contain different carbohydrate motifs in proximity within the side chains. A new building block suitable for the solid-phase polymer synthesis of precision glycomacromolecules was developed with a branching point in the side chain that bears a free alkyne and a TIPS-protected alkyne moiety, which enables the subsequent attachment of different carbohydrate motifs by on-resin copper-mediated azide-alkyne cycloaddition reactions. Applying this synthetic strategy, heteromultivalent glycooligomers presenting fragments of histo-blood group antigens and human milk oligosaccharides were synthesized and tested for their binding behavior towards bacterial lectin LecB.
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Affiliation(s)
- Katharina S Bücher
- Institute of Organic and Macromolecular Chemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Patrick B Konietzny
- Institute of Organic and Macromolecular Chemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Nicole L Snyder
- Department of Chemistry, Davidson College, Davidson, NC, USA
| | - Laura Hartmann
- Institute of Organic and Macromolecular Chemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
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30
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Haksar D, de Poel E, van Ufford LQ, Bhatia S, Haag R, Beekman J, Pieters RJ. Strong Inhibition of Cholera Toxin B Subunit by Affordable, Polymer-Based Multivalent Inhibitors. Bioconjug Chem 2019; 30:785-792. [PMID: 30629410 PMCID: PMC6429436 DOI: 10.1021/acs.bioconjchem.8b00902] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
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Cholera is a potentially
fatal bacterial infection that affects
a large number of people in developing countries. It is caused by
the cholera toxin (CT), an AB5 toxin secreted by Vibrio cholera. The toxin comprises a toxic A-subunit
and a pentameric B-subunit that bind to the intestinal cell surface.
Several monovalent and multivalent inhibitors of the toxin have been
synthesized but are too complicated and expensive for practical use
in developing countries. Meta-nitrophenyl α-galactoside (MNPG)
is a known promising ligand for CT, and here mono- and multivalent
compounds based on MNPG were synthesized. We present the synthesis
of MNPG in greatly improved yields and its use while linked to a multivalent
scaffold. We used economical polymers as multivalent scaffolds, namely,
polyacrylamide, dextran, and hyperbranched polyglycerols (hPGs). Copper-catalyzed
alkyne azide cycloaddition reaction (CuAAC) produced the inhibitors
that were tested in an ELISA-type assay and an intestinal organoid
swelling inhibition assay. The inhibitory properties varied widely
depending on the type of polymer, and the most potent conjugates showed
IC50 values in the nanomolar range.
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Affiliation(s)
- Diksha Haksar
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences , Utrecht University , Universiteitsweg 99 , 3584 CG Utrecht , The Netherlands
| | - Eyleen de Poel
- Department of Pediatric Pulmonology, Regenerative Medicine Center Utrecht , University Medical Centre Utrecht , Lundlaan 6 , 3508 GA Utrecht , The Netherlands
| | - Linda Quarles van Ufford
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences , Utrecht University , Universiteitsweg 99 , 3584 CG Utrecht , The Netherlands
| | - Sumati Bhatia
- Institut für Chemie und Biochemie Organische Chemie , Freie Universität at Berlin , Takustr. 3 , 14195 Berlin , Germany
| | - Rainer Haag
- Institut für Chemie und Biochemie Organische Chemie , Freie Universität at Berlin , Takustr. 3 , 14195 Berlin , Germany
| | - Jeffrey Beekman
- Department of Pediatric Pulmonology, Regenerative Medicine Center Utrecht , University Medical Centre Utrecht , Lundlaan 6 , 3508 GA Utrecht , The Netherlands
| | - Roland J Pieters
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences , Utrecht University , Universiteitsweg 99 , 3584 CG Utrecht , The Netherlands
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31
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Wilkins L, Badi N, Du Prez F, Gibson MI. Double-Modified Glycopolymers from Thiolactones to Modulate Lectin Selectivity and Affinity. ACS Macro Lett 2018; 7:1498-1502. [PMID: 30662815 PMCID: PMC6326524 DOI: 10.1021/acsmacrolett.8b00825] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 12/03/2018] [Indexed: 12/15/2022]
Abstract
Multivalent glycomaterials show high affinity toward lectins but are often nonselective as they lack the precise 3-D presentation found in native glycans. Here, thiolactone chemistry is exploited to enable the synthesis of glycopolymers with both a primary binding (galactose) and a variable secondary binding unit in close proximity to each other on the linker. These polymers are used to target the Cholera toxin B subunit, CTxB, inspired by its native branched glycan target, GM-1. The secondary, nonbinding unit was shown to dramatically modulate affinity and selectivity toward the Cholera toxin. These increasingly complex glycopolymers, assembled using accessible chemistry, can help breach the synthetic/biological divide to obtain future glycomimetics.
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Affiliation(s)
- Laura
E. Wilkins
- Department
of Chemistry, University of Warwick, Coventry CV4 7AL, U.K.
| | - Nezha Badi
- Polymer
Chemistry Research Group, Centre of Macromolecular Chemistry (CMaC),
Department of Organic and Macromolecular Chemistry, Faculty of Sciences, Ghent University, Krijgslaan 281 S4-bis, Ghent B-9000, Belgium
| | - Filip Du Prez
- Polymer
Chemistry Research Group, Centre of Macromolecular Chemistry (CMaC),
Department of Organic and Macromolecular Chemistry, Faculty of Sciences, Ghent University, Krijgslaan 281 S4-bis, Ghent B-9000, Belgium
| | - Matthew I. Gibson
- Department
of Chemistry, University of Warwick, Coventry CV4 7AL, U.K.
- Warwick
Medical School, University of Warwick, Coventry CV4 7AL, U.K.
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32
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Pshezhetsky AV, Ashmarina M. Keeping it trim: roles of neuraminidases in CNS function. Glycoconj J 2018; 35:375-386. [PMID: 30088207 PMCID: PMC6182584 DOI: 10.1007/s10719-018-9837-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 07/25/2018] [Accepted: 07/27/2018] [Indexed: 12/11/2022]
Abstract
The sialylated glyconjugates (SGC) are found in abundance on the surface of brain cells, where they form a dense array of glycans mediating cell/cell and cell/protein recognition in numerous physiological and pathological processes. Metabolic genetic blocks in processing and catabolism of SGC result in development of severe storage disorders, dominated by CNS involvement including marked neuroinflammation and neurodegeneration, the pathophysiological mechanisms of which are still discussed. SGC patterns in the brain are cell and organelle-specific, dynamic and maintained by highly coordinated processes of their biosynthesis, trafficking, processing and catabolism. The changes in the composition of SGC during development and aging of the brain cannot be explained based solely on the regulation of the SGC-synthesizing enzymes, sialyltransferases, suggesting that neuraminidases (sialidases) hydrolysing the removal of terminal sialic acid residues also play an essential role. In the current review we summarize the roles of three mammalian neuraminidases: neuraminidase 1, neuraminidase 3 and neuraminidase 4 in processing brain SGC. Emerging data demonstrate that these enzymes with different, yet overlapping expression patterns, intracellular localization and substrate specificity play essential roles in the physiology of the CNS.
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Affiliation(s)
- Alexey V Pshezhetsky
- Sainte-Justine Hospital Research Center, Department of Paediatrics, University of Montreal, CHU Ste-Justine, Centre de recherche, 3175 Côte-Sainte-Catherine, Montréal, Québec, H3T 1C5, Canada.
- Department of Anatomy and Cell Biology, McGill University, Montreal, H3A0C7, Canada.
| | - Mila Ashmarina
- Sainte-Justine Hospital Research Center, Department of Paediatrics, University of Montreal, CHU Ste-Justine, Centre de recherche, 3175 Côte-Sainte-Catherine, Montréal, Québec, H3T 1C5, Canada
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33
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Abstract
Cholera is a diarrheal disease caused by a protein toxin released by Vibrio cholera in the host's intestine. The toxin enters intestinal epithelial cells after binding to specific carbohydrates on the cell surface. Over recent years, considerable effort has been invested in developing inhibitors of toxin adhesion that mimic the carbohydrate ligand, with particular emphasis on exploiting the multivalency of the toxin to enhance activity. In this review we introduce the structural features of the toxin that have guided the design of diverse inhibitors and summarise recent developments in the field.
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Affiliation(s)
- Vajinder Kumar
- Department of Chemistry, Akal University, Talwandi Sabo, Punjab, India
- School of Chemistry and Astbury Centre for Structural Molecular Biology, University of Leeds, LS2 9JT, UK
| | - W Bruce Turnbull
- School of Chemistry and Astbury Centre for Structural Molecular Biology, University of Leeds, LS2 9JT, UK
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