1
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Theillet FX, Luchinat E. In-cell NMR: Why and how? PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2022; 132-133:1-112. [PMID: 36496255 DOI: 10.1016/j.pnmrs.2022.04.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 04/19/2022] [Accepted: 04/27/2022] [Indexed: 06/17/2023]
Abstract
NMR spectroscopy has been applied to cells and tissues analysis since its beginnings, as early as 1950. We have attempted to gather here in a didactic fashion the broad diversity of data and ideas that emerged from NMR investigations on living cells. Covering a large proportion of the periodic table, NMR spectroscopy permits scrutiny of a great variety of atomic nuclei in all living organisms non-invasively. It has thus provided quantitative information on cellular atoms and their chemical environment, dynamics, or interactions. We will show that NMR studies have generated valuable knowledge on a vast array of cellular molecules and events, from water, salts, metabolites, cell walls, proteins, nucleic acids, drugs and drug targets, to pH, redox equilibria and chemical reactions. The characterization of such a multitude of objects at the atomic scale has thus shaped our mental representation of cellular life at multiple levels, together with major techniques like mass-spectrometry or microscopies. NMR studies on cells has accompanied the developments of MRI and metabolomics, and various subfields have flourished, coined with appealing names: fluxomics, foodomics, MRI and MRS (i.e. imaging and localized spectroscopy of living tissues, respectively), whole-cell NMR, on-cell ligand-based NMR, systems NMR, cellular structural biology, in-cell NMR… All these have not grown separately, but rather by reinforcing each other like a braided trunk. Hence, we try here to provide an analytical account of a large ensemble of intricately linked approaches, whose integration has been and will be key to their success. We present extensive overviews, firstly on the various types of information provided by NMR in a cellular environment (the "why", oriented towards a broad readership), and secondly on the employed NMR techniques and setups (the "how", where we discuss the past, current and future methods). Each subsection is constructed as a historical anthology, showing how the intrinsic properties of NMR spectroscopy and its developments structured the accessible knowledge on cellular phenomena. Using this systematic approach, we sought i) to make this review accessible to the broadest audience and ii) to highlight some early techniques that may find renewed interest. Finally, we present a brief discussion on what may be potential and desirable developments in the context of integrative studies in biology.
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Affiliation(s)
- Francois-Xavier Theillet
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France.
| | - Enrico Luchinat
- Dipartimento di Scienze e Tecnologie Agro-Alimentari, Alma Mater Studiorum - Università di Bologna, Piazza Goidanich 60, 47521 Cesena, Italy; CERM - Magnetic Resonance Center, and Neurofarba Department, Università degli Studi di Firenze, 50019 Sesto Fiorentino, Italy
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2
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Phạm TTT, Rainey JK. On-cell nuclear magnetic resonance spectroscopy to probe cell surface interactions. Biochem Cell Biol 2021; 99:683-692. [PMID: 33945753 DOI: 10.1139/bcb-2021-0052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Nuclear magnetic resonance (NMR) spectroscopy allows determination of atomic-level information about intermolecular interactions, molecular structure, and molecular dynamics in the cellular environment. This may be broadly divided into studies focused on obtaining detailed molecular information in the intracellular context ("in-cell") or those focused on characterizing molecules or events at the cell surface ("on-cell"). In this review, we outline some key NMR techniques applied for on-cell NMR studies through both solution-state and solid-state NMR and survey studies that have used these techniques to uncover key information. We particularly focus on application of on-cell NMR spectroscopy to characterize ligand interactions with cell surface membrane proteins such as G-protein coupled receptors (GPCRs), receptor tyrosine kinases, etc. These techniques allow for quantification of binding affinities, competitive binding assays, delineation of portions of ligands involved in binding, ligand bound-state conformational determination, evaluation of receptor structuring and dynamics, and inference of distance constraints characteristic of the ligand-receptor bound state. Excitingly, it is possible to avoid the barriers of production and purification of membrane proteins while obtaining directly physiologically-relevant information through on-cell NMR. We also provide a briefer survey of the applicability of on-cell NMR approaches to other classes of cell surface molecule.
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Affiliation(s)
- Trần Thanh Tâm Phạm
- Dalhousie University, 3688, Department of Biochemistry & Molecular Biology, Halifax, Nova Scotia, Canada;
| | - Jan K Rainey
- Dalhousie University, 3688, Department of Biochemistry & Molecular Biology, Halifax, Canada;
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3
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Fiebig T, Cramer JT, Bethe A, Baruch P, Curth U, Führing JI, Buettner FFR, Vogel U, Schubert M, Fedorov R, Mühlenhoff M. Structural and mechanistic basis of capsule O-acetylation in Neisseria meningitidis serogroup A. Nat Commun 2020; 11:4723. [PMID: 32948778 PMCID: PMC7501274 DOI: 10.1038/s41467-020-18464-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 08/20/2020] [Indexed: 02/08/2023] Open
Abstract
O-Acetylation of the capsular polysaccharide (CPS) of Neisseria meningitidis serogroup A (NmA) is critical for the induction of functional immune responses, making this modification mandatory for CPS-based anti-NmA vaccines. Using comprehensive NMR studies, we demonstrate that O-acetylation stabilizes the labile anomeric phosphodiester-linkages of the NmA-CPS and occurs in position C3 and C4 of the N-acetylmannosamine units due to enzymatic transfer and non-enzymatic ester migration, respectively. To shed light on the enzymatic transfer mechanism, we solved the crystal structure of the capsule O-acetyltransferase CsaC in its apo and acceptor-bound form and of the CsaC-H228A mutant as trapped acetyl-enzyme adduct in complex with CoA. Together with the results of a comprehensive mutagenesis study, the reported structures explain the strict regioselectivity of CsaC and provide insight into the catalytic mechanism, which relies on an unexpected Gln-extension of a classical Ser-His-Asp triad, embedded in an α/β-hydrolase fold.
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Affiliation(s)
- Timm Fiebig
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany.
| | | | - Andrea Bethe
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Petra Baruch
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Ute Curth
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Jana I Führing
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
- Fraunhofer International Consortium for Anti-Infective Research (iCAIR), Hannover, Germany
| | - Falk F R Buettner
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Ulrich Vogel
- Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
| | - Mario Schubert
- Department of Biosciences, University of Salzburg, Salzburg, Austria
| | - Roman Fedorov
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Martina Mühlenhoff
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany.
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4
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Enotarpi J, Tontini M, Balocchi C, van der Es D, Auberger L, Balducci E, Carboni F, Proietti D, Casini D, Filippov DV, Overkleeft HS, van der Marel GA, Colombo C, Romano MR, Berti F, Costantino P, Codeé JDC, Lay L, Adamo R. A stabilized glycomimetic conjugate vaccine inducing protective antibodies against Neisseria meningitidis serogroup A. Nat Commun 2020; 11:4434. [PMID: 32895393 PMCID: PMC7477203 DOI: 10.1038/s41467-020-18279-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 08/09/2020] [Indexed: 12/15/2022] Open
Abstract
Neisseria meningitidis serogroup A capsular polysaccharide (MenA CPS) consists of (1 → 6)-2-acetamido-2-deoxy-α-D-mannopyranosyl phosphate repeating units, O-acetylated at position C3 or C4. Glycomimetics appear attractive to overcome the CPS intrinsic lability in physiological media, due to cleavage of the phosphodiester bridge, and to develop a stable vaccine with longer shelf life in liquid formulation. Here, we generate a series of non-acetylated carbaMenA oligomers which are proven more stable than the CPS. An octamer (DP8) inhibits the binding of a MenA specific bactericidal mAb and polyclonal serum to the CPS, and is selected for further in vivo testing. However, its CRM197 conjugate raises murine antibodies towards the non-acetylated CPS backbone, but not the natural acetylated form. Accordingly, random O-acetylation of the DP8 is performed, resulting in a structure (Ac-carbaMenA) showing improved inhibition of anti-MenA CPS antibody binding and, after conjugation to CRM197, eliciting anti-MenA protective murine antibodies, comparably to the vaccine benchmark.
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MESH Headings
- Animals
- Antibodies, Bacterial/analysis
- Antibodies, Neutralizing/chemistry
- Bacterial Capsules/immunology
- Biomimetics/methods
- Glycoconjugates/chemical synthesis
- Glycoconjugates/immunology
- Mice
- Neisseria meningitidis, Serogroup A/chemistry
- Neisseria meningitidis, Serogroup A/drug effects
- Neisseria meningitidis, Serogroup A/immunology
- Polysaccharides, Bacterial/chemical synthesis
- Polysaccharides, Bacterial/chemistry
- Polysaccharides, Bacterial/immunology
- Vaccines, Conjugate/chemistry
- Vaccines, Conjugate/microbiology
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Affiliation(s)
- Jacopo Enotarpi
- Department of Chemistry and CRC Polymeric Materials (LaMPo), University of Milan, Milan, Italy
- Department of Bioorganic Synthesis, Leiden University, 2333, Leiden, The Netherlands
| | | | | | - Daan van der Es
- Department of Bioorganic Synthesis, Leiden University, 2333, Leiden, The Netherlands
| | - Ludovic Auberger
- Department of Chemistry and CRC Polymeric Materials (LaMPo), University of Milan, Milan, Italy
| | | | | | | | | | - Dmitri V Filippov
- Department of Bioorganic Synthesis, Leiden University, 2333, Leiden, The Netherlands
| | - Hermen S Overkleeft
- Department of Bioorganic Synthesis, Leiden University, 2333, Leiden, The Netherlands
| | | | - Cinzia Colombo
- Department of Chemistry and CRC Polymeric Materials (LaMPo), University of Milan, Milan, Italy
| | | | | | | | - Jeroen D C Codeé
- Department of Bioorganic Synthesis, Leiden University, 2333, Leiden, The Netherlands.
| | - Luigi Lay
- Department of Chemistry and CRC Polymeric Materials (LaMPo), University of Milan, Milan, Italy.
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Affiliation(s)
- Darón I. Freedberg
- Center for Biologics Evaluation and ResearchFood and Drug Administration 10903 New Hampshire Ave. Silver Spring MD. 20993
| | - Jeahoo Kwon
- Center for Biologics Evaluation and ResearchFood and Drug Administration 10903 New Hampshire Ave. Silver Spring MD. 20993
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6
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Righi V, Constantinou C, Kesarwani M, Rahme LG, Tzika AA. Effects of a small, volatile bacterial molecule on Pseudomonas aeruginosa bacteria using whole cell high-resolution magic angle spinning nuclear magnetic resonance spectroscopy and genomics. Int J Mol Med 2018; 42:2129-2136. [PMID: 30015850 PMCID: PMC6108874 DOI: 10.3892/ijmm.2018.3760] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 11/19/2015] [Indexed: 01/07/2023] Open
Abstract
In the present study, high-resolution magic-angle spinning (HRMAS) nuclear magnetic resonance (NMR) spectroscopy was applied to live Pseudomonas aeruginosa (PA) bacterial cells to determine the metabolome of this opportunistic Gram-negative human pathogen, and in particular, its response to the volatile aromatic low molecular weight signaling molecule, 2-aminoacetophenone (2-AA). Multi-dimensional HRMAS NMR is a promising method which may be used to determine the in vivo metabolome of live intact bacterial cells; 2-AA is produced by PA and triggers the emergence of phenotypes that promote chronic infection phenotypes in in vitro and in vivo (animal) models. In the present study, we applied one-dimensional and two-dimensional proton (1H) HRMAS NMR to PA cells which were grown with or without 2-AA in order to examine the associations between metabolites and cellular processes in response to 2-AA. We also compared whole-genome transcriptome profiles of PA cells grown with or without 2-AA and found that 2-AA promoted profound metabolic changes in the PA cells. By comparing the whole-genome transcriptome profiles and metabolomic analysis, we demonstrated that 2-AA profoundly reprogramed the gene expression and metabolic profiles of the cells. Our in vivo1H HRMAS NMR spectroscopy may prove to be a helpful tool in the validation of gene functions, the study of pathogenic mechanisms, the classification of microbial strains into functional/clinical groups and the testing of anti-bacterial agents.
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Affiliation(s)
- Valeria Righi
- NMR Surgical Laboratory, Center for Surgery, Innovation and Bioengineering, Department of Surgery, Massachusetts General and Shriners Burns Hospitals, Harvard Medical School, Boston, MA 02114, USA
| | - Caterina Constantinou
- NMR Surgical Laboratory, Center for Surgery, Innovation and Bioengineering, Department of Surgery, Massachusetts General and Shriners Burns Hospitals, Harvard Medical School, Boston, MA 02114, USA
| | - Meenu Kesarwani
- Molecular Surgery Laboratory, Department of Surgery, Microbiology and Immunobiology, Harvard Medical School and Molecular Surgery Laboratory, Center for Surgery, Innovation and Bioengineering, Department of Surgery, Massachusetts General and Shriners Burns Hospitals, Boston, MA 02114, USA
| | - Laurence G Rahme
- Molecular Surgery Laboratory, Department of Surgery, Microbiology and Immunobiology, Harvard Medical School and Molecular Surgery Laboratory, Center for Surgery, Innovation and Bioengineering, Department of Surgery, Massachusetts General and Shriners Burns Hospitals, Boston, MA 02114, USA
| | - A Aria Tzika
- NMR Surgical Laboratory, Center for Surgery, Innovation and Bioengineering, Department of Surgery, Massachusetts General and Shriners Burns Hospitals, Harvard Medical School, Boston, MA 02114, USA
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7
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Hennessey JP, Costantino P, Talaga P, Beurret M, Ravenscroft N, Alderson MR, Zablackis E, Prasad AK, Frasch C. Lessons Learned and Future Challenges in the Design and Manufacture of Glycoconjugate Vaccines. CARBOHYDRATE-BASED VACCINES: FROM CONCEPT TO CLINIC 2018. [DOI: 10.1021/bk-2018-1290.ch013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Affiliation(s)
| | | | - Philippe Talaga
- Department of Analytical Research and Development, Sanofi Pasteur, Marcy l’Etoile 69280, France
| | - Michel Beurret
- Janssen Vaccines & Prevention B.V., Leiden, 2301 CA, The Netherlands
| | - Neil Ravenscroft
- Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | | | - Earl Zablackis
- Analytical Process Technology, Sanofi Pasteur, Swiftwater, Pennsylvania 18370, United States
| | - A. Krishna Prasad
- Pfizer Vaccines Research and Development, Pearl River, New York 10965, United States
| | - Carl Frasch
- Consultant, Martinsburg, West Virginia 25402, United States
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8
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Simpson AJ, Simpson MJ, Soong R. Environmental Nuclear Magnetic Resonance Spectroscopy: An Overview and a Primer. Anal Chem 2017; 90:628-639. [PMID: 29131590 DOI: 10.1021/acs.analchem.7b03241] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
NMR spectroscopy is a versatile tool for the study of structure and interactions in environmental media such as air, soil, and water as well as monitoring the metabolic responses of living organisms to an ever changing environment. Part review, part perspective, and part tutorial, this Feature is aimed at nonspecialists who are interested in learning more about the potential and impact of NMR spectroscopy in environmental research.
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Affiliation(s)
- André J Simpson
- Environmental NMR Centre and Department of Physical & Environmental Sciences, University of Toronto Scarborough , Toronto, Ontario, Canada , M1C 1A4
| | - Myrna J Simpson
- Environmental NMR Centre and Department of Physical & Environmental Sciences, University of Toronto Scarborough , Toronto, Ontario, Canada , M1C 1A4
| | - Ronald Soong
- Environmental NMR Centre and Department of Physical & Environmental Sciences, University of Toronto Scarborough , Toronto, Ontario, Canada , M1C 1A4
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9
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Grant MR, Tymon LS, Helms GL, Thomashow LS, Kent Keller C, Harsh JB. Biofilm adaptation to iron availability in the presence of biotite and consequences for chemical weathering. GEOBIOLOGY 2016; 14:588-598. [PMID: 27384343 DOI: 10.1111/gbi.12187] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2015] [Accepted: 04/22/2016] [Indexed: 06/06/2023]
Abstract
Bacteria in nature often live within biofilms, exopolymeric matrices that provide a favorable environment that can differ markedly from their surroundings. Biofilms have been found growing on mineral surfaces and are expected to play a role in weathering those surfaces, but a clear understanding of how environmental factors, such as trace-nutrient limitation, influence this role is lacking. Here, we examine biofilm development by Pseudomonas putida in media either deficient or sufficient in Fe during growth on biotite, an Fe rich mineral, or on glass. We hypothesized that the bacteria would respond to Fe deficiency by enhancing biotite dissolution and by the formation of binding sites to inhibit Fe leaching from the system. Glass coupons acted as a no-Fe control to investigate whether biofilm response depended on the presence of Fe in the supporting solid. Biofilms grown on biotite, as compared to glass, had significantly greater biofilm biomass, specific numbers of viable cells (SNVC), and biofilm cation concentrations of K, Mg, and Fe, and these differences were greater when Fe was deficient in the medium. Scanning electron microscopy (SEM) confirmed that biofilm growth altered the biotite surface, smoothing the rough, jagged edges of channels scratched by hand on the biotite, and dissolving away small, easy-to-access particles scattered across the planar surface. High-resolution magic angle spinning proton nuclear magnetic resonance (HRMAS 1 H NMR) spectroscopy showed that, in the Fe-deficient medium, the relative amount of polysaccharide nearly doubled relative to that in biofilms grown in the medium amended with Fe. The results imply that the bacteria responded to the Fe deficiency by obtaining Fe from biotite and used the biofilm matrix to enhance weathering and as a sink for released cation nutrients. These results demonstrate one mechanism by which biofilms may help soil microbes overcome nutrient deficiencies in oligotrophic systems.
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Affiliation(s)
- M R Grant
- Department of Crops and Soil Sciences, Washington State University, Pullman, WA, USA.
| | - L S Tymon
- Department of Plant Soil and Entomological Sciences, University of Idaho, Moscow, ID, USA
| | - G L Helms
- Nuclear Magnetic Resonance Spectroscopy Center, Washington State University, Pullman, WA, USA
| | - L S Thomashow
- Root Disease and Biological Control Research Unit, USDA-ARS, Washington State University, Pullman, WA, USA
| | - C Kent Keller
- School of the Environment, Washington State University, Pullman, WA, USA
| | - J B Harsh
- Department of Crops and Soil Sciences, Washington State University, Pullman, WA, USA
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10
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Marchetti R, Perez S, Arda A, Imberty A, Jimenez‐Barbero J, Silipo A, Molinaro A. "Rules of Engagement" of Protein-Glycoconjugate Interactions: A Molecular View Achievable by using NMR Spectroscopy and Molecular Modeling. ChemistryOpen 2016; 5:274-96. [PMID: 27547635 PMCID: PMC4981046 DOI: 10.1002/open.201600024] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Indexed: 12/20/2022] Open
Abstract
Understanding the dynamics of protein-ligand interactions, which lie at the heart of host-pathogen recognition, represents a crucial step to clarify the molecular determinants implicated in binding events, as well as to optimize the design of new molecules with therapeutic aims. Over the last decade, advances in complementary biophysical and spectroscopic methods permitted us to deeply dissect the fine structural details of biologically relevant molecular recognition processes with high resolution. This Review focuses on the development and use of modern nuclear magnetic resonance (NMR) techniques to dissect binding events. These spectroscopic methods, complementing X-ray crystallography and molecular modeling methodologies, will be taken into account as indispensable tools to provide a complete picture of protein-glycoconjugate binding mechanisms related to biomedicine applications against infectious diseases.
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Affiliation(s)
- Roberta Marchetti
- Department of Chemical SciencestUniversity of Napoli Federico IIVia Cintia 480126NapoliItaly
| | - Serge Perez
- Department Molecular Pharmacochemistry UMR 5063CNRS and University of GrenobleAlpes, BP 5338041 Grenoble cedex 9France
| | - Ana Arda
- Bizkaia Technological ParkCIC bioGUNEBuilding 801A-148160Derio-BizkaiaSpain
| | - Anne Imberty
- Centre de Recherche sur les CNRSand University of Grenoble Macromolécules Végétales, UPR 5301Alpes, BP 5338041Grenoble cedex 9France
| | | | - Alba Silipo
- Department of Chemical SciencestUniversity of Napoli Federico IIVia Cintia 480126NapoliItaly
| | - Antonio Molinaro
- Department of Chemical SciencestUniversity of Napoli Federico IIVia Cintia 480126NapoliItaly
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11
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Changes in the NMR Metabolic Profile of Live Human Neuron-Like SH-SY5Y Cells Exposed to Interferon-α2. J Neuroimmune Pharmacol 2015; 11:142-52. [DOI: 10.1007/s11481-015-9641-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Accepted: 10/27/2015] [Indexed: 12/29/2022]
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Tanniou A, Vandanjon L, Gonçalves O, Kervarec N, Stiger-Pouvreau V. Rapid geographical differentiation of the European spread brown macroalga Sargassum muticum using HRMAS NMR and Fourier-Transform Infrared spectroscopy. Talanta 2015; 132:451-6. [PMID: 25476330 DOI: 10.1016/j.talanta.2014.09.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Revised: 08/21/2014] [Accepted: 09/02/2014] [Indexed: 12/13/2022]
Abstract
Two recent techniques based on chemical footprinting analysis, HRMAS NMR and FTIR spectroscopy, were tested on a brown macroalgal model. These powerful and easily-to-use techniques allowed us to discriminate Sargassum muticum specimens collected in five different countries along Atlantic coasts, from Portugal to Norway. HRMAS NMR and FTIR permitted the obtaining of an overview of metabolites produced by the alga. Based on spectra analysis, results allowed us to successfully group the samples according to their geographical origin. HRMAS NMR and FTIR spectroscopy respectively point out the relation between the geographical localization and the chemical composition and demonstrated macromolecules variations regarding to environmental stress. Then, our results are discussed in regard of the powerful of these techniques together with the variability of the main molecules produced by Sargassum muticum along the Atlantic coasts.
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Affiliation(s)
- Anaëlle Tanniou
- LEMAR UMR CNRS UBO IRD IFREMER 6539, Université de Bretagne Occidentale (UBO), Institut Universitaire Européen de la Mer (IUEM), Technopôle Brest-Iroise, Rue Dumont d׳Urville, Plouzané 29280, France
| | - Laurent Vandanjon
- GEPEA UMR CNRS 6144, Université de Nantes, Laboratoire GEPEA, CRTT, 44602 Saint-Nazaire, France; LBCM EA 3884, Université de Bretagne Sud (UBS), IUEM, Campus de Tohannic, 56000 Vannes, France
| | - Olivier Gonçalves
- GEPEA UMR CNRS 6144, Université de Nantes, Laboratoire GEPEA, CRTT, 44602 Saint-Nazaire, France
| | - Nelly Kervarec
- Service RMN-RPE, UFR Sciences et Techniques, Université de Bretagne Occidentale (UBO), Avenue Le Gorgeu, 29200 Brest, France
| | - Valérie Stiger-Pouvreau
- LEMAR UMR CNRS UBO IRD IFREMER 6539, Université de Bretagne Occidentale (UBO), Institut Universitaire Européen de la Mer (IUEM), Technopôle Brest-Iroise, Rue Dumont d׳Urville, Plouzané 29280, France.
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13
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Wong A, Boutin C, Aguiar PM. (1)H high resolution magic-angle coil spinning (HR-MACS) μNMR metabolic profiling of whole Saccharomyces cervisiae cells: a demonstrative study. Front Chem 2014; 2:38. [PMID: 24971307 PMCID: PMC4053607 DOI: 10.3389/fchem.2014.00038] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 05/28/2014] [Indexed: 11/17/2022] Open
Abstract
The low sensitivity and thus need for large sample volume is one of the major drawbacks of Nuclear Magnetic Resonance (NMR) spectroscopy. This is especially problematic for performing rich metabolic profiling of scarce samples such as whole cells or living organisms. This study evaluates a 1H HR-MAS approach for metabolic profiling of small volumes (250 nl) of whole cells. We have applied an emerging micro-NMR technology, high-resolution magic-angle coil spinning (HR-MACS), to study whole Saccharomyces cervisiae cells. We find that high-resolution high-sensitivity spectra can be obtained with only 19 million cells and, as a demonstration of the metabolic profiling potential, we perform two independent metabolomics studies identifying the significant metabolites associated with osmotic stress and aging.
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Affiliation(s)
- Alan Wong
- CEA Saclay, DSM, IRAMIS, UMR CEA/CNRS 3299 - NIMBE, Laboratoire Structure et Dynamique par Résonance Magnétique Gif-sur-Yvette, France
| | - Céline Boutin
- CEA Saclay, DSM, IRAMIS, UMR CEA/CNRS 3299 - NIMBE, Laboratoire Structure et Dynamique par Résonance Magnétique Gif-sur-Yvette, France
| | - Pedro M Aguiar
- Department of Chemistry, University of York Heslington, York, UK
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Hung MC, Christodoulides M. The biology of Neisseria adhesins. BIOLOGY 2013; 2:1054-109. [PMID: 24833056 PMCID: PMC3960869 DOI: 10.3390/biology2031054] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 07/01/2013] [Accepted: 07/03/2013] [Indexed: 01/15/2023]
Abstract
Members of the genus Neisseria include pathogens causing important human diseases such as meningitis, septicaemia, gonorrhoea and pelvic inflammatory disease syndrome. Neisseriae are found on the exposed epithelia of the upper respiratory tract and the urogenital tract. Colonisation of these exposed epithelia is dependent on a repertoire of diverse bacterial molecules, extending not only from the surface of the bacteria but also found within the outer membrane. During invasive disease, pathogenic Neisseriae also interact with immune effector cells, vascular endothelia and the meninges. Neisseria adhesion involves the interplay of these multiple surface factors and in this review we discuss the structure and function of these important molecules and the nature of the host cell receptors and mechanisms involved in their recognition. We also describe the current status for recently identified Neisseria adhesins. Understanding the biology of Neisseria adhesins has an impact not only on the development of new vaccines but also in revealing fundamental knowledge about human biology.
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Affiliation(s)
- Miao-Chiu Hung
- Neisseria Research, Molecular Microbiology, Clinical and Experimental Sciences, Sir Henry Wellcome Laboratories, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, SO16 6YD, UK.
| | - Myron Christodoulides
- Neisseria Research, Molecular Microbiology, Clinical and Experimental Sciences, Sir Henry Wellcome Laboratories, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, SO16 6YD, UK.
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15
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Righi V, Constantinou C, Kesarwani M, Rahme LG, Tzika AA. Live-cell high resolution magic angle spinning magnetic resonance spectroscopy for in vivo analysis of Pseudomonas aeruginosa metabolomics. Biomed Rep 2013; 1:707-712. [PMID: 24649014 DOI: 10.3892/br.2013.148] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Accepted: 07/03/2013] [Indexed: 01/26/2023] Open
Abstract
Pseudomonas aeruginosa (PA) is a pathogenic gram-negative bacterium that is widespread in nature, inhabiting soil, water, plants and animals. PA is a prevalent cause of deleterious human infections, particularly in patients whose host defense mechanisms have been compromised. Metabolomics is an important tool used to study host-pathogen interactions and to identify novel therapeutic targets and corresponding compounds. The aim of the present study was to report the metabolic profile of live PA bacteria using in vivo high-resolution magic angle spinning (HRMAS) nuclear magnetic resonance spectroscopy (NMR), in combination with 1- and 2-dimensional HRMAS NMR. This methodology provides a new and powerful technique to rapidly interrogate the metabolome of intact bacterial cells and has several advantages over traditional techniques that identify metabolome components from disrupted cells. Furthermore, application of multidimensional HRMAS NMR, in combination with the novel technique total through-Bond correlation Spectroscopy (TOBSY), is a promising approach that may be used to obtain in vivo metabolomics information from intact live bacterial cells and can mediate such analyses in a short period of time. Moreover, HRMAS 1H NMR enables the investigation of the associations between metabolites and cell processes. In the present study, we detected and quantified several informative metabolic molecules in live PA cells, including N-acetyl, betaine, citrulline, alanine and glycine, which are important in peptidoglycan synthesis. The results provided a complete metabolic profile of PA for future studies of PA clinical isolates and mutants. In addition, this in vivo NMR biomedical approach might have clinical utility and should prove useful in gene function validation, the study of pathogenetic mechanisms, the classification of microbial strains into functional/clinical groups, the testing of anti-bacterial agents and the determination of metabolic profiles of bacterial mutants.
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Affiliation(s)
- Valeria Righi
- Nuclear Magnetic Resonance Surgical Laboratory, Department of Surgery, Division of Burns, Massachusetts General Hospital and Shriners Burns Institute, Harvard Medical School, Boston, MA 02114, USA ; Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA ; Department for Life Quality, University of Bologna, Rimini 47921, Italy
| | - Caterina Constantinou
- Nuclear Magnetic Resonance Surgical Laboratory, Department of Surgery, Division of Burns, Massachusetts General Hospital and Shriners Burns Institute, Harvard Medical School, Boston, MA 02114, USA ; Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Meenu Kesarwani
- Molecular Surgery Laboratory, Department of Surgery, Division of Burns, Massachusetts General Hospital and Shriners Burns Institute, Harvard Medical School, Boston, MA 02114, USA
| | - Laurence G Rahme
- Molecular Surgery Laboratory, Department of Surgery, Division of Burns, Massachusetts General Hospital and Shriners Burns Institute, Harvard Medical School, Boston, MA 02114, USA
| | - Aria A Tzika
- Nuclear Magnetic Resonance Surgical Laboratory, Department of Surgery, Division of Burns, Massachusetts General Hospital and Shriners Burns Institute, Harvard Medical School, Boston, MA 02114, USA ; Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
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16
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Zandomeneghi G, Ilg K, Aebi M, Meier BH. On-Cell MAS NMR: Physiological Clues from Living Cells. J Am Chem Soc 2012; 134:17513-9. [DOI: 10.1021/ja307467p] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Karin Ilg
- Microbiology, ETH Zurich, Wolfgang-Pauli Str. 10, 8093 Zurich Switzerland
| | - Markus Aebi
- Microbiology, ETH Zurich, Wolfgang-Pauli Str. 10, 8093 Zurich Switzerland
| | - Beat H. Meier
- Physical Chemistry, ETH Zurich, Wolfgang-Pauli Str. 10, 8093 Zurich Switzerland
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17
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Ubale RV, D'Souza MJ, Infield DT, McCarty NA, Zughaier SM. Formulation of meningococcal capsular polysaccharide vaccine-loaded microparticles with robust innate immune recognition. J Microencapsul 2012; 30:28-41. [PMID: 22657751 DOI: 10.3109/02652048.2012.692402] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Neisseria meningitidis is a leading cause of bacterial meningitis and sepsis associated with a high mortality rate. Capsular polysaccharides (CPSs) are a major virulence factor and form the basis for serogroup designation and protective vaccines. The current polysaccharide meningococcal vaccines are available but are very expensive and require chemical conjugation. Here, we report a novel meningococcal vaccine formulation consisting of meningococcal CPS polymers encapsulated in albumin-based biodegradable microparticles that slowly release antigen and induce robust innate immune responses. Vaccines that elicit innate immunity are reported to have enhanced and protective adaptive immune responses. In this study, the meningococcal CPS-loaded microparticles, but not the empty microparticles, induced the release of IL-8, TNF-α and IL-1β, enhanced phagocytic capacity and induced robust autophagy in macrophages. The novel meningococcal vaccine microparticles are robustly taken up by macrophages and elicit strong innate immune responses that enhance antigen presentation which is a prerequisite for inducing adaptive immunity.
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Affiliation(s)
- Ruhi V Ubale
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, Mercer University, Atlanta, GA 30341, USA
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18
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Abstract
Meningococcal meningitis is feared because of the rapid onset of severe disease from mild symptoms and, therefore, is an important target for vaccine research. Five serogroups, defined by the structures of their capsular polysaccharides, are responsible for the vast majority of disease. Protection against four of these five serogroups can be obtained with polysaccharide or glycoconjugate vaccines, in which fragments of the capsular polysaccharides attached to a carrier protein generate anticarbohydrate immune responses, whilst protection against group B disease requires protein immunogens, often presented in vesicles containing outer membrane proteins. Glycoconjugate vaccines are now an established technology, but outer-membrane protein vaccines are still under development and present significant challenges. This review discusses physicochemical approaches to the characterization and quality control of these vaccines, as well as highlighting the problems and differences in vaccine design required for protection against different serogroups of the same species of pathogen.
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19
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Beckonert O, Coen M, Keun HC, Wang Y, Ebbels TMD, Holmes E, Lindon JC, Nicholson JK. High-resolution magic-angle-spinning NMR spectroscopy for metabolic profiling of intact tissues. Nat Protoc 2010; 5:1019-32. [PMID: 20539278 DOI: 10.1038/nprot.2010.45] [Citation(s) in RCA: 302] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Metabolic profiling, metabolomic and metabonomic studies require robust study protocols for any large-scale comparisons and evaluations. Detailed methods for solution-state NMR spectroscopy have been summarized in an earlier protocol. This protocol details the analysis of intact tissue samples by means of high-resolution magic-angle-spinning (HR-MAS) NMR spectroscopy and we provide a detailed description of sample collection, preparation and analysis. Described here are (1)H NMR spectroscopic techniques such as the standard one-dimensional, relaxation-edited, diffusion-edited and two-dimensional J-resolved pulse experiments, as well as one-dimensional (31)P NMR spectroscopy. These are used to monitor different groups of metabolites, e.g., sugars, amino acids and osmolytes as well as larger molecules such as lipids, non-invasively. Through the use of NMR-based diffusion coefficient and relaxation times measurements, information on molecular compartmentation and mobility can be gleaned. The NMR methods are often combined with statistical analysis for further metabonomics analysis and biomarker identification. The standard acquisition time per sample is 8-10 min for a simple one-dimensional (1)H NMR spectrum, giving access to metabolite information while retaining tissue integrity and hence allowing direct comparison with histopathology and MRI/MRS findings or the evaluation together with biofluid metabolic-profiling data.
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Affiliation(s)
- Olaf Beckonert
- Biomolecular Medicine, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, South Kensington, London, UK
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20
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Reid CW, Fulton KM, Twine SM. Never take candy from a stranger: the role of the bacterial glycome in host–pathogen interactions. Future Microbiol 2010; 5:267-88. [DOI: 10.2217/fmb.09.103] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
With the comprehensive study and complete sequencing of the Haemophilus influenzae genome in 1995 came the term ‘genomics’ and the beginning of the ‘omics’ era. Since this time, several analogous fields, such as transcriptomics and proteomics, have emerged. While growth and advancement in these fields have increased understanding of microbial virulence, the study of bacterial glycomes is still in its infancy and little is known concerning their role in host–pathogen interactions. Bacterial glycomics is challenging owing to the diversity of glyco-conjugate molecules, vast array of unusual sugars and limited number of analytical approaches available. However, recent advances in glycomics technologies offer the potential for exploration and characterization of both the structures and functions of components of bacterial glycomes in a systematic manner. Such characterization is a prerequisite for discerning the role of bacterial glycans in the interaction between host defences and bacterial virulence factors.
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Affiliation(s)
- Christopher W Reid
- National Research Council – Institute for Biological Science, Ottawa, Ontario, K1A 0R6, Canada
| | - Kelly M Fulton
- National Research Council – Institute for Biological Science, Ottawa, Ontario, K1A 0R6, Canada
| | - Susan M Twine
- National Research Council – Institute for Biological Science, Ottawa, Ontario, K1A 0R6, Canada
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21
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Zartler ER, Porambo RJ, Anderson CL, Chen LH, Yu J, Nahm MH. Structure of the capsular polysaccharide of pneumococcal serotype 11A reveals a novel acetylglycerol that is the structural basis for 11A subtypes. J Biol Chem 2009; 284:7318-29. [PMID: 19114709 PMCID: PMC2652282 DOI: 10.1074/jbc.m807952200] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2008] [Revised: 12/24/2008] [Indexed: 11/06/2022] Open
Abstract
We have undertaken a structural assessment of Streptococcus pneumoniae 11A polysaccharide as well as two clinical isolates related to 11A. The clinical isolates were labeled 11Aalpha and 11Abeta. The result of our experiments is a revision to the old structure for S. pneumoniae 11A polysaccharide. The new structure differs from the old structure in both the primary connectivities and acetylation pattern. We also show that 11A contains an acetylglycerol-PO4 moiety, a substitution that is heretofore unknown in the bacterial polysaccharide literature. The two clinical isolates were also structurally characterized. 11Aalpha was determined to be identical to 11A. 11Abeta is a new serotype, which differs from 11A in the absence of the acetylation of the glycerol-PO4 moiety and a different acetylation pattern of the saccharides. Thus, we propose that the acetylglycerol is the structural basis for 11Aalpha and 11Abeta subtypes.
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Affiliation(s)
- Edward R Zartler
- Bioprocess Analytical and Formulation Sciences, Merck Research Laboratories, Merck and Company, West Point, Pennsylvania 19486, USA.
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22
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Joshi VS, Bajaj IB, Survase SA, Singhal RS, Kennedy JF. Meningococcal polysaccharide vaccines: A review. Carbohydr Polym 2009. [DOI: 10.1016/j.carbpol.2008.09.032] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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23
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Li W. Multidimensional HRMAS NMR: a platform for in vivo studies using intact bacterial cells. Analyst 2007; 131:777-81. [PMID: 16874945 DOI: 10.1039/b605110c] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In vivo analysis in whole cell bacteria, especially the native tertiary structures of the bacterial cell wall, remains an unconquered frontier. The current understanding of bacterial cell wall structures has been based on destructive analysis of individual components. These in vitro results may not faithfully reflect the native structural and conformational information. Multidimensional High Resolution Magic Angle Spinning NMR (HRMAS NMR) has evolved to be a powerful technique in a variety of in vivo studies, including live bacterial cells. Existing studies of HRMAS NMR in bacteria, technical consideration of its successful application, and current limitations in studying true human pathogens are briefly reviewed in this report.
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Affiliation(s)
- Wei Li
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
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24
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Azurmendi HF, Vionnet J, Wrightson L, Trinh LB, Shiloach J, Freedberg DI. Extracellular structure of polysialic acid explored by on cell solution NMR. Proc Natl Acad Sci U S A 2007; 104:11557-61. [PMID: 17609375 PMCID: PMC1906721 DOI: 10.1073/pnas.0704404104] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2006] [Indexed: 11/18/2022] Open
Abstract
The capsular polysaccharide of the pathogens Neisseria meningitidis serogroup B and of Escherichia coli K1, alpha(2 --> 8) polysialic acid (PSA), is unusual, because when injected into adult humans, it generates little or no antibody. In contrast, people infected with these pathogens generate specific serum antibodies. A structural study on cells is used to address this anomaly by characterizing antigen structures in vivo. We introduce on cell multidimensional solution NMR spectroscopy for direct observation of PSA on E. coli bacteria. Using 13C,15N-labeled PSA, we applied a combination of heteronuclear NMR methods, such as heteronuclear single quantum coherence, HNCA, and HNCO, in vivo. Analysis reveals that free and cell-bound PSA are structurally similar, indicating that the poor immunogenicity of PSA is not due to major structural differences between cells and purified PSA. The 13C linewidths of PSA on cells are 2 to 3 times larger than the corresponding ones in free PSA. The possible implications of the differences between free and on cell PSA are discussed. In addition, we demonstrate the suitability of the method for in vivo kinetic studies.
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Affiliation(s)
- Hugo F. Azurmendi
- *Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration, 1401 Rockville Pike, Rockville, MD 20852-1448; and
| | - Justine Vionnet
- *Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration, 1401 Rockville Pike, Rockville, MD 20852-1448; and
| | - Lauren Wrightson
- *Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration, 1401 Rockville Pike, Rockville, MD 20852-1448; and
| | - Loc B. Trinh
- Biotechnology Unit, MSC 5522, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Joseph Shiloach
- Biotechnology Unit, MSC 5522, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Darón I. Freedberg
- *Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration, 1401 Rockville Pike, Rockville, MD 20852-1448; and
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25
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King MR, Steenbergen SM, Vimr ER. Going for baroque at the Escherichia coli K1 cell surface. Trends Microbiol 2007; 15:196-202. [PMID: 17418577 DOI: 10.1016/j.tim.2007.03.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2006] [Revised: 03/01/2007] [Accepted: 03/22/2007] [Indexed: 01/23/2023]
Abstract
Phase variation is usually thought of as the stochastic switching between alternatively expressed ('on') and unexpressed ('off') phenotypic states. However, coupling synthesis of a monotonous homopolysaccharide to a mechanism of random but incomplete chemical modification produces almost infinite structural variation. Potentially limitless variability implies that evolution can produce highly ornate or extravagant flourishes reminiscent of the baroque style. Here, we describe an analysis of capsular polysialic acid form variation in Escherichia coli K1, demonstrating that the large number of variant structures is controlled by a single contingency locus. The mechanism for generating maximum structural diversity from maximal genetic parsimony is conferred by a simple translational switch carried on a K1-specific prophage.
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Affiliation(s)
- Michael R King
- Laboratory of Sialobiology, Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, IL 61802, USA
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26
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Nikolaev AV, Botvinko IV, Ross AJ. Natural phosphoglycans containing glycosyl phosphate units: structural diversity and chemical synthesis. Carbohydr Res 2007; 342:297-344. [PMID: 17092493 DOI: 10.1016/j.carres.2006.10.006] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2006] [Revised: 09/30/2006] [Accepted: 10/04/2006] [Indexed: 11/22/2022]
Abstract
An anomeric phosphodiester linkage formed by a glycosyl phosphate unit and a hydroxyl group of another monosaccharide is found in many glycopolymers of the outer membrane in bacteria (e.g., capsular polysaccharides and lipopolysaccharides), yeasts and protozoa. The polymers (phosphoglycans) composed of glycosyl phosphate (or oligoglycosyl phosphate) repeating units could be chemically classified as poly(glycosyl phosphates). Their importance as immunologically active components of the cell wall and/or capsule of numerous microorganisms upholds the need to develop routes for the chemical preparation of these biopolymers. In this paper, we (1) present a review of the primary structures (known to date) of natural phosphoglycans from various sources, which contain glycosyl phosphate units, and (2) discuss different approaches and recent achievements in the synthesis of glycosyl phosphosaccharides and poly(glycosyl phosphates).
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Affiliation(s)
- Andrei V Nikolaev
- College of Life Sciences, Division of Biological Chemistry and Molecular Microbiology, University of Dundee, Dundee DD1 5EH, UK.
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