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Lee SY, Marando VM, Smelyansky SR, Kim DE, Calabretta PJ, Warner TC, Bryson BD, Kiessling LL. Selective Glycan Labeling of Mannose-Containing Glycolipids in Mycobacteria. J Am Chem Soc 2024; 146:377-385. [PMID: 38112296 PMCID: PMC10914408 DOI: 10.1021/jacs.3c09495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
Mycobacterium tuberculosis (Mtb) is one of history's most successful human pathogens. By subverting typical immune responses, Mtb can persist within a host until conditions become favorable for growth and proliferation. Virulence factors that enable mycobacteria to modulate host immune systems include a suite of mannose-containing glycolipids: phosphatidylinositol mannosides, lipomannan, and lipoarabinomannan (LAM). Despite their importance, tools for their covalent capture, modification, and imaging are limited. Here, we describe a chemical biology strategy to detect and visualize these glycans. Our approach, biosynthetic incorporation, is to synthesize a lipid-glycan precursor that can be incorporated at a late-stage step in glycolipid biosynthesis. We previously demonstrated selective mycobacterial arabinan modification by biosynthetic incorporation using an exogenous donor. This report reveals that biosynthetic labeling is general and selective: it allows for cell surface mannose-containing glycolipid modification without nonspecific labeling of mannosylated glycoproteins. Specifically, we employed azido-(Z,Z)-farnesyl phosphoryl-β-d-mannose probes and took advantage of the strain-promoted azide-alkyne cycloaddition to label and directly visualize the localization and dynamics of mycobacterial mannose-containing glycolipids. Our studies highlight the generality and utility of biosynthetic incorporation as the probe structure directs the selective labeling of distinct glycans. The disclosed agents allowed for direct tracking of the target immunomodulatory glycolipid dynamics in cellulo. We anticipate that these probes will facilitate investigating the diverse biological roles of these glycans.
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Affiliation(s)
- So Young Lee
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Victoria M. Marando
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Stephanie R. Smelyansky
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Daria E. Kim
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Phillip J. Calabretta
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, University of Wisconsin Madison, Madison, Wisconsin 53706, United States
| | - Theodore C. Warner
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Bryan D. Bryson
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts 02139, USA
| | - Laura L. Kiessling
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
- Department of Chemistry, University of Wisconsin Madison, Madison, Wisconsin 53706, United States
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts 02139, USA
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2
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Mosquera-Restrepo SF, Zuberogoïtia S, Gouxette L, Layre E, Gilleron M, Stella A, Rengel D, Burlet-Schiltz O, Caro AC, Garcia LF, Segura C, Peláez Jaramillo CA, Rojas M, Nigou J. A Mycobacterium tuberculosis fingerprint in human breath allows tuberculosis detection. Nat Commun 2022; 13:7751. [PMID: 36517492 PMCID: PMC9751131 DOI: 10.1038/s41467-022-35453-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 12/05/2022] [Indexed: 12/15/2022] Open
Abstract
An estimated one-third of tuberculosis (TB) cases go undiagnosed or unreported. Sputum samples, widely used for TB diagnosis, are inefficient at detecting infection in children and paucibacillary patients. Indeed, developing point-of-care biomarker-based diagnostics that are not sputum-based is a major priority for the WHO. Here, in a proof-of-concept study, we tested whether pulmonary TB can be detected by analyzing patient exhaled breath condensate (EBC) samples. We find that the presence of Mycobacterium tuberculosis (Mtb)-specific lipids, lipoarabinomannan lipoglycan, and proteins in EBCs can efficiently differentiate baseline TB patients from controls. We used EBCs to track the longitudinal effects of antibiotic treatment in pediatric TB patients. In addition, Mtb lipoarabinomannan and lipids were structurally distinct in EBCs compared to ex vivo cultured bacteria, revealing specific metabolic and biochemical states of Mtb in the human lung. This provides essential information for the rational development or improvement of diagnostic antibodies, vaccines and therapeutic drugs. Our data collectively indicate that EBC analysis can potentially facilitate clinical diagnosis of TB across patient populations and monitor treatment efficacy. This affordable, rapid and non-invasive approach seems superior to sputum assays and has the potential to be implemented at point-of-care.
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Affiliation(s)
- Sergio Fabián Mosquera-Restrepo
- grid.412881.60000 0000 8882 5269Cellular Immunology and Immunogenetics Group (GICIG), Institute of Medical Research, Faculty of Medicine, University Research Headquarters (SIU), University of Antioquia (UdeA), Medellin, Colombia
| | - Sophie Zuberogoïtia
- grid.15781.3a0000 0001 0723 035XInstitute of Pharmacology and Structural Biology (IPBS), University of Toulouse, CNRS, University of Toulouse III-Paul Sabatier, Toulouse, France
| | - Lucie Gouxette
- grid.15781.3a0000 0001 0723 035XInstitute of Pharmacology and Structural Biology (IPBS), University of Toulouse, CNRS, University of Toulouse III-Paul Sabatier, Toulouse, France
| | - Emilie Layre
- grid.15781.3a0000 0001 0723 035XInstitute of Pharmacology and Structural Biology (IPBS), University of Toulouse, CNRS, University of Toulouse III-Paul Sabatier, Toulouse, France
| | - Martine Gilleron
- grid.15781.3a0000 0001 0723 035XInstitute of Pharmacology and Structural Biology (IPBS), University of Toulouse, CNRS, University of Toulouse III-Paul Sabatier, Toulouse, France
| | - Alexandre Stella
- grid.15781.3a0000 0001 0723 035XInstitute of Pharmacology and Structural Biology (IPBS), University of Toulouse, CNRS, University of Toulouse III-Paul Sabatier, Toulouse, France
| | - David Rengel
- grid.15781.3a0000 0001 0723 035XInstitute of Pharmacology and Structural Biology (IPBS), University of Toulouse, CNRS, University of Toulouse III-Paul Sabatier, Toulouse, France
| | - Odile Burlet-Schiltz
- grid.15781.3a0000 0001 0723 035XInstitute of Pharmacology and Structural Biology (IPBS), University of Toulouse, CNRS, University of Toulouse III-Paul Sabatier, Toulouse, France
| | - Ana Cecilia Caro
- grid.412881.60000 0000 8882 5269Interdisciplinary Group for Molecular Studies (GIEM), Institute of Chemistry, Faculty of Exact and Natural Sciences. University of Antioquia (UdeA), Medellin, Colombia
| | - Luis F. Garcia
- grid.412881.60000 0000 8882 5269Cellular Immunology and Immunogenetics Group (GICIG), Institute of Medical Research, Faculty of Medicine, University Research Headquarters (SIU), University of Antioquia (UdeA), Medellin, Colombia
| | - César Segura
- grid.412881.60000 0000 8882 5269Malaria Group, University Research Headquarters, University of Antioquia (UdeA), Medellín, Colombia
| | - Carlos Alberto Peláez Jaramillo
- grid.412881.60000 0000 8882 5269Interdisciplinary Group for Molecular Studies (GIEM), Institute of Chemistry, Faculty of Exact and Natural Sciences. University of Antioquia (UdeA), Medellin, Colombia
| | - Mauricio Rojas
- grid.412881.60000 0000 8882 5269Cellular Immunology and Immunogenetics Group (GICIG), Institute of Medical Research, Faculty of Medicine, University Research Headquarters (SIU), University of Antioquia (UdeA), Medellin, Colombia ,grid.412881.60000 0000 8882 5269Flow Cytometry Core, University Research Headquarters (SIU), University of Antioquia, UdeA, Medellín, Colombia
| | - Jérôme Nigou
- grid.15781.3a0000 0001 0723 035XInstitute of Pharmacology and Structural Biology (IPBS), University of Toulouse, CNRS, University of Toulouse III-Paul Sabatier, Toulouse, France
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3
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Leprosy: A Review of Epidemiology, Clinical Diagnosis, and Management. J Trop Med 2022; 2022:8652062. [PMID: 35832335 PMCID: PMC9273393 DOI: 10.1155/2022/8652062] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 05/20/2022] [Accepted: 06/22/2022] [Indexed: 01/03/2023] Open
Abstract
Leprosy is a neglected infectious disease caused by acid-fast bacillus Mycobacterium leprae. It primarily affects the skin and then progresses to a secondary stage, causing peripheral neuropathy with potential long-term disability along with stigma. Leprosy patients account for a significant proportion of the global disease burden. Previous efforts to improve diagnostic and therapeutic techniques have focused on leprosy in adults, whereas childhood leprosy has been relatively neglected. This review aims to update the diagnostic and therapeutic recommendations for adult and childhood leprosy. This review summarizes the clinical, bacteriological, and immunological approaches used in the diagnosis of leprosy. As strategies for the diagnosis and management of leprosy continue to develop better and more advanced knowledge, control and prevention of leprosy are crucial.
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4
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Nakayama H, Oshima E, Hotta T, Hanafusa K, Nakamura K, Yokoyama N, Ogawa H, Takamori K, Iwabuchi K. Identification of anti-lipoarabinomannan antibodies against mannan core and their effects on phagocytosis of mycobacteria by human neutrophils. Tuberculosis (Edinb) 2022; 132:102165. [PMID: 35045376 DOI: 10.1016/j.tube.2022.102165] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 01/06/2022] [Accepted: 01/07/2022] [Indexed: 10/19/2022]
Abstract
Mycobacterium tuberculosis (MTB) and M. avium-intracellulare complex (MAC) enter host phagocytes, such as neutrophils through lipoarabinomannan (LAM) binding to pattern-recognition receptors, inducing innate immune responses including phagocytosis. Phagocytosis of mycobacteria by human neutrophils depends on the binding of α(1 → 2)-monomannose branching α(1 → 6)-mannan core of LAM/lipomannan (LM), a common component among mycobacterial species, to lactosylceramide (LacCer)-enriched lipid microdomains. We investigated the binding specificities of several anti-LAM antibodies (Abs) to LAMs/LM and found anti-LAM monoclonal IgMs TMDU3 and LA066 were directed against mannan core. Each IgM showed different binding specificity to mannan core. Confocal and stimulated emission depletion microscopy revealed TMDU3 and LA066 strongly bind to MTB and MAC, respectively. Flow cytometric analysis revealed human neutrophils do not express Dectin-2, DC-SIGN or mannose receptor. Furthermore, neutrophil phagocytosis of mycobacteria was markedly inhibited by TMDU3 and LA066, respectively. Similarly, treatment of each mAb with neutrophils reduced the numbers of intracellular MAC. Together, our results suggest that the interaction of LacCer-enriched lipid microdomains with mannan core and its blocking are therapeutic or diagnostic targets for both TB and non-tuberculous mycobacteria infection.
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Affiliation(s)
- Hitoshi Nakayama
- Laboratory of Biochemistry, Juntendo University Faculty of Health Care and Nursing, Urayasu, Chiba, Japan; Institute for Environmental and Gender-specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Chiba, Japan; Infection Control Nursing, Juntendo University Graduate School of Health Care and Nursing, Urayasu, Chiba, Japan.
| | - Eriko Oshima
- Institute for Environmental and Gender-specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Chiba, Japan
| | - Tomomi Hotta
- Institute for Environmental and Gender-specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Chiba, Japan
| | - Kei Hanafusa
- Institute for Environmental and Gender-specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Chiba, Japan
| | - Kota Nakamura
- Department of Respiratory Medicine, Juntendo University Faculty of Medicine, Bunkyo-ku, Tokyo, Japan
| | - Noriko Yokoyama
- Institute for Environmental and Gender-specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Chiba, Japan
| | - Hideoki Ogawa
- Institute for Environmental and Gender-specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Chiba, Japan
| | - Kenji Takamori
- Institute for Environmental and Gender-specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Chiba, Japan
| | - Kazuhisa Iwabuchi
- Laboratory of Biochemistry, Juntendo University Faculty of Health Care and Nursing, Urayasu, Chiba, Japan; Institute for Environmental and Gender-specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Chiba, Japan; Infection Control Nursing, Juntendo University Graduate School of Health Care and Nursing, Urayasu, Chiba, Japan.
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5
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Ishida E, Corrigan DT, Malonis RJ, Hofmann D, Chen T, Amin AG, Chatterjee D, Joe M, Lowary TL, Lai JR, Achkar JM. Monoclonal antibodies from humans with Mycobacterium tuberculosis exposure or latent infection recognize distinct arabinomannan epitopes. Commun Biol 2021; 4:1181. [PMID: 34642445 PMCID: PMC8511196 DOI: 10.1038/s42003-021-02714-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 09/23/2021] [Indexed: 12/16/2022] Open
Abstract
The surface polysacharide arabinomannan (AM) and related glycolipid lipoarabinomannan (LAM) play critical roles in tuberculosis pathogenesis. Human antibody responses to AM/LAM are heterogenous and knowledge of reactivity to specific glycan epitopes at the monoclonal level is limited, especially in individuals who can control M. tuberculosis infection. We generated human IgG mAbs to AM/LAM from B cells of two asymptomatic individuals exposed to or latently infected with M. tuberculosis. Here, we show that two of these mAbs have high affinity to AM/LAM, are non-competing, and recognize different glycan epitopes distinct from other anti-AM/LAM mAbs reported. Both mAbs recognize virulent M. tuberculosis and nontuberculous mycobacteria with marked differences, can be used for the detection of urinary LAM, and can detect M. tuberculosis and LAM in infected lungs. These mAbs enhance our understanding of the spectrum of antibodies to AM/LAM epitopes in humans and are valuable for tuberculosis diagnostic and research applications. Elise Ishida et al. generate human monoclonal antibodies that can selectively recognize specific oligosaccharide epitopes of the polysaccharides arabinomannan and lipoarabinomannan, which are critical for M. tuberculosis pathogenesis. The authors demonstrate the utility of these antibodies in both diagnostic and laboratory settings, making them important tools for M. tuberculosis research.
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Affiliation(s)
- Elise Ishida
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Devin T Corrigan
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Ryan J Malonis
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Daniel Hofmann
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Tingting Chen
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Anita G Amin
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Delphi Chatterjee
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Maju Joe
- Department of Chemistry, University of Alberta, Edmonton, AB, Canada
| | - Todd L Lowary
- Department of Chemistry, University of Alberta, Edmonton, AB, Canada.,Institute of Biological Chemistry, Academia Sinica, Nangang, Taipei, Taiwan.,Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
| | - Jonathan R Lai
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Jacqueline M Achkar
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, USA. .,Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, USA.
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6
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An ABC transporter Wzm-Wzt catalyzes translocation of lipid-linked galactan across the plasma membrane in mycobacteria. Proc Natl Acad Sci U S A 2021; 118:2023663118. [PMID: 33879617 DOI: 10.1073/pnas.2023663118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Mycobacterium tuberculosis, one of the deadliest pathogens in human history, is distinguished by a unique, multilayered cell wall, which offers the bacterium a high level of protection from the attacks of the host immune system. The primary structure of the cell wall core, composed of covalently linked peptidoglycan, branched heteropolysaccharide arabinogalactan, and mycolic acids, is well known, and numerous enzymes involved in the biosynthesis of its components are characterized. The cell wall biogenesis takes place at both cytoplasmic and periplasmic faces of the plasma membrane, and only recently some of the specific transport systems translocating the metabolic intermediates between these two compartments have been characterized [M. Jackson, C. M. Stevens, L. Zhang, H. I. Zgurskaya, M. Niederweis, Chem. Rev., 10.1021/acs.chemrev.0c00869 (2020)]. In this work, we use CRISPR interference methodology in Mycobacterium smegmatis to functionally characterize an ATP-binding cassette (ABC) transporter involved in the translocation of galactan precursors across the plasma membrane. We show that genetic knockdown of the transmembrane subunit of the transporter results in severe morphological changes and the accumulation of an aberrantly long galactan precursor. Based on similarities with structures and functions of specific O-antigen ABC transporters of gram-negative bacteria [C. Whitfield, D. M. Williams, S. D. Kelly, J. Biol. Chem. 295, 10593-10609 (2020)], we propose a model for coupled synthesis and export of the galactan polymer precursor in mycobacteria.
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7
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van der Horst M, Karamchand L, Bauer WS, Nel AJM, Blackburn JM, Wright DW. The cyanobacterial lectin, microvirin-N, enhances the specificity and sensitivity of lipoarabinomannan-based TB diagnostic tests. Analyst 2021; 146:1207-1215. [PMID: 33367346 PMCID: PMC8374243 DOI: 10.1039/d0an01725f] [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: 08/27/2020] [Accepted: 12/09/2020] [Indexed: 01/04/2023]
Abstract
Tuberculosis (TB) is one of the top ten causes of death globally, despite being treatable. The eradication of TB disease requires, amongst others, diagnostic tests with high specificity and sensitivity that will work at the point of care (POC) in low-resource settings. The TB surface glycolipid antigen, mannose-capped lipoarabinomannan (ManLAM) currently serves as the only POC molecular diagnostic biomarker suitable for use in low cost immunoassays. Here, we demonstrate the high affinity and exceptional specificity of microvirin-N (MVN), a 14.3 kDa cyanobacterial lectin, toward H37Rv TB ManLAM and utilize it to develop a novel on-bead ELISA. MVN binds to ManLAM with sub-picomolar binding affinity, but does not bind to other variants of LAM expressed by non-pathogenic mycobacteria - a level of binding specificity and affinity that current commercially available anti-LAM antibodies cannot achieve. An on-bead ELISA was subsequently developed using MVN-functionalized magnetic beads which allows for the specific capture of ManLAM from human urine with a limit of detection (LOD) of 1.14 ng mL-1 and no cross-reactivity when tested with PILAM, a variant of LAM found on non-pathogenic mycobacteria.
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Affiliation(s)
- Megan van der Horst
- Department of Chemistry, Vanderbilt UniversityStation B 351822NashvilleTN37235USA
| | - Leshern Karamchand
- University of Cape Town, Faculty of Health Sciences, Institute of Infectious Disease and Molecular Medicine; Department of Integrative Biomedical SciencesAnzio RoadObservatory7925South Africa
| | - Westley S. Bauer
- Department of Chemistry, Vanderbilt UniversityStation B 351822NashvilleTN37235USA
| | - Andrew J. M. Nel
- University of Cape Town, Faculty of Health Sciences, Institute of Infectious Disease and Molecular Medicine; Department of Integrative Biomedical SciencesAnzio RoadObservatory7925South Africa
| | - Jonathan M. Blackburn
- University of Cape Town, Faculty of Health Sciences, Institute of Infectious Disease and Molecular Medicine; Department of Integrative Biomedical SciencesAnzio RoadObservatory7925South Africa
| | - David W. Wright
- Department of Chemistry, Vanderbilt UniversityStation B 351822NashvilleTN37235USA
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Islam SM, Havranek B, Ibnat Z, Roy PN. New Insights into the Role of Hydrogen Bonding in Furanoside Binding to Protein. J Phys Chem B 2020; 124:1919-1927. [PMID: 32075374 DOI: 10.1021/acs.jpcb.9b11924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Furanosides have been subjected to extensive studies owing to their inherent flexibility, which is believed to play an important role in the survival and pathogenicity of different disease-causing organisms in the human body. This study reports the binding free energy (ΔG) and specificity of arabinofuranose oligosaccharides to a protein, arabinanase (Arb43A), with the use of potential of mean force (PMF) calculations using the umbrella-sampling simulations. Long molecular dynamics simulations have been carried out to understand intermolecular interactions in the arabinofuranose-protein complex. The PMF for pulling the α-(1 → 5)-linked L-arabinohexaose (ligand) from the protein provides a large free energy of binding, -16.8 kcal/mol. The ΔG of the nonreducing arabinotriose end is found to be -12.6 kcal/mol, while the ΔG of the reducing end is calculated to be -7.7 kcal/mol. In the absence of nonreducing arabinotrioside, the ΔG of the reducing arabinotrioside is -8.5 kcal/mol. Similarly, in the absence of reducing arabinotrioside, the ΔG of the nonreducing arabinotrioside is calculated to be -9.4 kcal/mol. The main contributing factor in the protein-arabinofuranose binding is hydrogen bonding. Acidic amino acid residues, Glu and Asp, with furanosides produce the strongest hydrogen bonding. Araf-A, B, and C construct the reducing arabinotriose, while Araf-D, E, and F construct the nonreducing arabinotriose. Since most of the hydrogen-bonding occupancies belong to Araf-D and Araf-E, the nonreducing arabinotriose is bound to protein more strongly than the reducing arabinotriose. This explains why the reducing arabinotriose can detach from the protein in nature.
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Affiliation(s)
- Shahidul M Islam
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607, United States
| | - Brandon Havranek
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607, United States
| | - Zahin Ibnat
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607, United States
| | - Pierre-Nicholas Roy
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
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9
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De P, Shi L, Boot C, Ordway D, McNeil M, Chatterjee D. Comparative Structural Study of Terminal Ends of Lipoarabinomannan from Mice Infected Lung Tissues and Urine of a Tuberculosis Positive Patient. ACS Infect Dis 2020; 6:291-301. [PMID: 31762254 DOI: 10.1021/acsinfecdis.9b00355] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Mycobacterium tuberculosis lipoarabinomannan (LAM) is a biomarker for active tuberculosis (TB) disease. The presence of LAM in the urine of TB patients, whether HIV positive or negative, has been validated by a gas chromatography/mass spectral method with good specificity (84%) and sensitivity (99%). However, point-of-care (POC) methods to detect TB LAM in urine using immunoassays have poor sensitivity and are limited to only HIV coinfected TB diagnosis. We hypothesized that these disappointing results with the POC methods may be due to the antibodies used in the immunoassays as there could be structural differences between LAM in vivo and LAM in vitro. To address this issue, we infected C3HeB/FeJ mice with M.tb W. Beijing SA161 and purified LAM from the lung. Analysis of these sources of LAM using a panel of existing mAbs revealed differences in epitope patterns. Conventionally, the non-reducing termini of LAM are identified by their release with endoarabinanase. These epitopes correspond to linear tetra-(Ara4), branched hexa-(Ara6) arabinofuranosides, and their mannose-capped versions. We discovered two distinct epitopes. In the first case, it was found that the non-reducing termini of LAM from M.tb strain SA161 are highly succinylated, especially when the LAM was isolated from the mouse lungs. In the second case, it was found that Cellulomonas endoarabinanase digestion of LAM from both SA161 and LAM from a TB+ HIV- patient's urine yielded epitopes based on 5 arabinoses as major components and a profound lack of Ara6. The epitopes based on 5 arabinoses from M.tb SA161 and from the LAM in human urine must result from underlying structural and thus epitope differences. These results suggest approaches to develop specific antibodies for POC tests for LAM in the urine of suspected TB patients.
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Affiliation(s)
- Prithwiraj De
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, 1682 Campus Delivery, Fort Collins, Colorado 80523, United States
| | - Libin Shi
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, 1682 Campus Delivery, Fort Collins, Colorado 80523, United States
| | - Claudia Boot
- Central Instrument Facility, Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Diane Ordway
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, 1682 Campus Delivery, Fort Collins, Colorado 80523, United States
| | - Michael McNeil
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, 1682 Campus Delivery, Fort Collins, Colorado 80523, United States
| | - Delphi Chatterjee
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, 1682 Campus Delivery, Fort Collins, Colorado 80523, United States
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10
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Zhou KL, Li X, Zhang XL, Pan Q. Mycobacterial mannose-capped lipoarabinomannan: a modulator bridging innate and adaptive immunity. Emerg Microbes Infect 2019; 8:1168-1177. [PMID: 31379262 PMCID: PMC6713153 DOI: 10.1080/22221751.2019.1649097] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Mannose-capped lipoarabinomannan (ManLAM) is a high molecular mass amphipathic lipoglycan identified in pathogenic Mycobacterium tuberculosis (M. tb) and M. bovis Bacillus Calmette-Guérin (BCG). ManLAM, serves as both an immunogen and a modulator of the host immune system, and its critical role in mycobacterial survival during infection has been well-characterized. ManLAM can be recognized by various types of receptors on both innate and adaptive immune cells, including macrophages, dendritic cells (DCs), neutrophils, natural killer T (NKT) cells, T cells and B cells. MamLAM has been shown to affect phagocytosis, cytokine production, antigen presentation, T cell activation and polarization, as well as antibody production. Exploring the mechanisms underlying the roles of ManLAM during mycobacterial infection will aid in improving tuberculosis (TB) prevention, diagnosis and treatment interventions. In this review, we highlight the interaction between ManLAM and receptors, intracellular signalling pathways triggered by ManLAM and its roles in both innate and adaptive immune responses.
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Affiliation(s)
- Kai-Liang Zhou
- a State Key Laboratory of Virology and Medical Research Institue, Hubei Province Key Laboratory of Allergy and Immunology and Department of Immunology, Wuhan University School of Medicine , Wuhan , People's Republic of China.,b The eighth hospital of Wuhan , Wuhan , People's Republic of China
| | - Xin Li
- a State Key Laboratory of Virology and Medical Research Institue, Hubei Province Key Laboratory of Allergy and Immunology and Department of Immunology, Wuhan University School of Medicine , Wuhan , People's Republic of China
| | - Xiao-Lian Zhang
- a State Key Laboratory of Virology and Medical Research Institue, Hubei Province Key Laboratory of Allergy and Immunology and Department of Immunology, Wuhan University School of Medicine , Wuhan , People's Republic of China
| | - Qin Pan
- a State Key Laboratory of Virology and Medical Research Institue, Hubei Province Key Laboratory of Allergy and Immunology and Department of Immunology, Wuhan University School of Medicine , Wuhan , People's Republic of China
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11
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Broger T, Tsionksy M, Mathew A, Lowary TL, Pinter A, Plisova T, Bartlett D, Barbero S, Denkinger CM, Moreau E, Katsuragi K, Kawasaki M, Nahid P, Sigal GB. Sensitive electrochemiluminescence (ECL) immunoassays for detecting lipoarabinomannan (LAM) and ESAT-6 in urine and serum from tuberculosis patients. PLoS One 2019; 14:e0215443. [PMID: 30998715 PMCID: PMC6472883 DOI: 10.1371/journal.pone.0215443] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 04/02/2019] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Tuberculosis (TB) infection was responsible for an estimated 1.3 million deaths in 2017. Better diagnostic tools are urgently needed. We sought to determine whether accurate TB antigen detection in blood or urine has the potential to meet the WHO target product profiles for detection of active TB. MATERIALS AND METHODS We developed Electrochemiluminescence (ECL) immunoassays for Lipoarabinomannan (LAM) and ESAT-6 detection with detection limits in the pg/ml range and used them to compare the concentrations of the two antigens in the urine and serum of 81 HIV-negative and -positive individuals with presumptive TB enrolled across diverse geographic sites. RESULTS LAM and ESAT-6 overall sensitivities in urine were 93% and 65% respectively. LAM and ESAT-6 overall sensitivities in serum were 55% and 46% respectively. Overall specificity was ≥97% in all assays. Sensitivities were higher in HIV-positive compared to HIV-negative patients for both antigens and both sample types, with signals roughly 10-fold higher on average in urine than in serum. The two antigens showed similar concentration ranges within the same sample type and correlated. CONCLUSIONS LAM and ESAT-6 can be detected in the urine and serum of TB patients, regardless of the HIV status and further gains in clinical sensitivity may be achievable through assay and reagent optimization. Accuracy in urine was higher with current methods and has the potential to meet the WHO accuracy target if the findings can be transferred to a point-of-care TB test.
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Affiliation(s)
| | - Michael Tsionksy
- Meso Scale Diagnostics, LLC., Rockville, Maryland, United States of America
| | - Anu Mathew
- Meso Scale Diagnostics, LLC., Rockville, Maryland, United States of America
| | - Todd L. Lowary
- Department of Chemistry and Alberta Glycomics Centre, University of Alberta, Edmonton, Alberta, Canada
| | - Abraham Pinter
- Public Health Research Institute Center, New Jersey Medical School, Rutgers University, Newark, New Jersey, United States of America
| | - Tatiana Plisova
- Meso Scale Diagnostics, LLC., Rockville, Maryland, United States of America
| | - Daniel Bartlett
- Meso Scale Diagnostics, LLC., Rockville, Maryland, United States of America
| | - Simone Barbero
- Meso Scale Diagnostics, LLC., Rockville, Maryland, United States of America
| | | | | | | | | | - Payam Nahid
- University of California, San Francisco, California, United States of America
| | - George B. Sigal
- Meso Scale Diagnostics, LLC., Rockville, Maryland, United States of America
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12
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A Novel Sensitive Immunoassay Targeting the 5-Methylthio-d-Xylofuranose-Lipoarabinomannan Epitope Meets the WHO's Performance Target for Tuberculosis Diagnosis. J Clin Microbiol 2018; 56:JCM.01338-18. [PMID: 30257899 PMCID: PMC6258851 DOI: 10.1128/jcm.01338-18] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2018] [Accepted: 09/19/2018] [Indexed: 12/30/2022] Open
Abstract
The only currently commercialized point-of-care assay for tuberculosis (TB) that measures lipoarabinomannan (LAM) in urine (Alere LF-LAM) has insufficient sensitivity. We evaluated the potential of 100 novel monoclonal antibody pairs targeting a variety of LAM epitopes on a sensitive electrochemiluminescence platform to improve the diagnostic accuracy. The only currently commercialized point-of-care assay for tuberculosis (TB) that measures lipoarabinomannan (LAM) in urine (Alere LF-LAM) has insufficient sensitivity. We evaluated the potential of 100 novel monoclonal antibody pairs targeting a variety of LAM epitopes on a sensitive electrochemiluminescence platform to improve the diagnostic accuracy. In the screening, many antibody pairs showed high reactivity to purified LAM but performed poorly at detecting urinary LAM in clinical samples, suggesting differences in antigen structure and immunoreactivity of the different LAM sources. The 12 best antibody pairs from the screening were tested in a retrospective case-control study with urine samples from 75 adults with presumptive TB. The best antibody pair reached femtomolar analytical sensitivity for LAM detection and an overall clinical sensitivity of 93% (confidence interval [CI], 80% to 97%) and specificity of 97% (CI, 85% to 100%). Importantly, in HIV-negative subjects positive for TB by sputum smear microscopy, the test achieved a sensitivity of 80% (CI, 55% to 93%). This compares to an overall sensitivity of 33% (CI, 20% to 48%) of the Alere LF-LAM and a sensitivity of 13% (CI, 4% to 38%) in HIV-negative subjects in the same sample set. The capture antibody targets a unique 5-methylthio-d-xylofuranose (MTX)-dependent epitope in LAM that is specific to the Mycobacterium tuberculosis complex and shows no cross-reactivity with fast-growing mycobacteria or other bacteria. The present study provides evidence that improved assay methods and reagents lead to increased diagnostic accuracy. The results of this work have informed the development of a sensitive and specific novel LAM point-of-care assay with the aim to meet the WHO's performance target for TB diagnosis.
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13
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Paris L, Magni R, Zaidi F, Araujo R, Saini N, Harpole M, Coronel J, Kirwan DE, Steinberg H, Gilman RH, Petricoin EF, Nisini R, Luchini A, Liotta L. Urine lipoarabinomannan glycan in HIV-negative patients with pulmonary tuberculosis correlates with disease severity. Sci Transl Med 2018; 9:9/420/eaal2807. [PMID: 29237757 PMCID: PMC6037412 DOI: 10.1126/scitranslmed.aal2807] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 05/25/2017] [Accepted: 10/30/2017] [Indexed: 11/12/2022]
Abstract
An accurate urine test for pulmonary tuberculosis (TB), affecting 9.6 million patients worldwide, is critically needed for surveillance and treatment management. Past attempts failed to reliably detect the mycobacterial glycan antigen lipoarabinomannan (LAM), a marker of active TB, in HIV-negative, pulmonary TB–infected patients’ urine (85% of 9.6 million patients). We apply a copper complex dye within a hydrogel nanocage that captures LAM with very high affinity, displacing interfering urine proteins. The technology was applied to study pretreatment urine from 48 Peruvian patients, all negative for HIV, with microbiologically confirmed active pulmonary TB. LAM was quantitatively measured in the urine with a sensitivity of >95%and a specificity of >80% (n = 101) in a concentration range of 14 to 2000 picograms per milliliter, as compared to non-TB, healthy and diseased, age-matched controls (evaluated by receiver operating characteristic analysis; area under the curve, 0.95; 95% confidence interval, 0.9005 to 0.9957). Urinary LAM was elevated in patients with a higher mycobacterial burden (n = 42), a higher proportion of weight loss (n = 37), or cough (n = 50). The technology can be configured in a variety of formats to detect a panel of previously undetectable very-low-abundance TB urinary analytes. Eight of nine patients who were smear-negative and culture-positive for TB tested positive for urinary LAM. This technology has broad implications for pulmonary TB screening, transmission control, and treatment management for HIV-negative patients.
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Affiliation(s)
- Luisa Paris
- George Mason University, Manassas, VA 20110, USA
| | - Ruben Magni
- George Mason University, Manassas, VA 20110, USA
| | - Fatima Zaidi
- George Mason University, Manassas, VA 20110, USA
| | - Robyn Araujo
- Queensland University of Technology, Brisbane, Queensland 4000, Australia
| | - Neal Saini
- George Mason University, Manassas, VA 20110, USA
| | | | | | | | | | | | | | | | | | - Lance Liotta
- George Mason University, Manassas, VA 20110, USA
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14
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Choudhary A, Patel D, Honnen W, Lai Z, Prattipati RS, Zheng RB, Hsueh YC, Gennaro ML, Lardizabal A, Restrepo BI, Garcia-Viveros M, Joe M, Bai Y, Shen K, Sahloul K, Spencer JS, Chatterjee D, Broger T, Lowary TL, Pinter A. Characterization of the Antigenic Heterogeneity of Lipoarabinomannan, the Major Surface Glycolipid of Mycobacterium tuberculosis, and Complexity of Antibody Specificities toward This Antigen. THE JOURNAL OF IMMUNOLOGY 2018; 200:3053-3066. [PMID: 29610143 PMCID: PMC5911930 DOI: 10.4049/jimmunol.1701673] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 02/16/2018] [Indexed: 12/17/2022]
Abstract
Lipoarabinomannan (LAM), the major antigenic glycolipid of Mycobacterium tuberculosis, is an important immunodiagnostic target for detecting tuberculosis (TB) infection in HIV-1–coinfected patients, and is believed to mediate a number of functions that promote infection and disease development. To probe the human humoral response against LAM during TB infection, several novel LAM-specific human mAbs were molecularly cloned from memory B cells isolated from infected patients and grown in vitro. The fine epitope specificities of these Abs, along with those of a panel of previously described murine and phage-derived LAM-specific mAbs, were mapped using binding assays against LAM Ags from several mycobacterial species and a panel of synthetic glycans and glycoconjugates that represented diverse carbohydrate structures present in LAM. Multiple reactivity patterns were seen that differed in their specificity for LAM from different species, as well as in their dependence on arabinofuranoside branching and nature of capping at the nonreducing termini. Competition studies with mAbs and soluble glycans further defined these epitope specificities and guided the design of highly sensitive immunodetection assays capable of detecting LAM in urine of TB patients, even in the absence of HIV-1 coinfection. These results highlighted the complexity of the antigenic structure of LAM and the diversity of the natural Ab response against this target. The information and novel reagents described in this study will allow further optimization of diagnostic assays for LAM and may facilitate the development of potential immunotherapeutic approaches to inhibit the functional activities of specific structural motifs in LAM.
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Affiliation(s)
- Alok Choudhary
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ 07103
| | - Deendayal Patel
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ 07103
| | - William Honnen
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ 07103
| | - Zhong Lai
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ 07103
| | - Raja Sekhar Prattipati
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ 07103
| | - Ruixiang Blake Zheng
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Ying-Chao Hsueh
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ 07103
| | - Maria Laura Gennaro
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ 07103
| | - Alfred Lardizabal
- Global Tuberculosis Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ 07103
| | - Blanca I Restrepo
- University of Texas Health Science Center at Houston, School of Public Health at Brownsville, Brownsville, TX 78520
| | | | - Maju Joe
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Yu Bai
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Ke Shen
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Kamar Sahloul
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - John S Spencer
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO 80523; and
| | - Delphi Chatterjee
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO 80523; and
| | - Tobias Broger
- Foundation for Innovative New Diagnostics, Geneva 1202, Switzerland
| | - Todd L Lowary
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Abraham Pinter
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ 07103;
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15
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Zheng RB, Jégouzo SAF, Joe M, Bai Y, Tran HA, Shen K, Saupe J, Xia L, Ahmed MF, Liu YH, Patil PS, Tripathi A, Hung SC, Taylor ME, Lowary TL, Drickamer K. Insights into Interactions of Mycobacteria with the Host Innate Immune System from a Novel Array of Synthetic Mycobacterial Glycans. ACS Chem Biol 2017; 12:2990-3002. [PMID: 29048873 PMCID: PMC5735379 DOI: 10.1021/acschembio.7b00797] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
![]()
An
array of homogeneous glycans representing all the major carbohydrate
structures present in the cell wall of the human pathogen Mycobacterium tuberculosis and other mycobacteria has been
probed with a panel of glycan-binding receptors expressed on cells
of the mammalian innate immune system. The results provide an overview
of interactions between mycobacterial glycans and receptors that mediate
uptake and survival in macrophages, dendritic cells, and sinusoidal
endothelial cells. A subset of the wide variety of glycan structures
present on mycobacterial surfaces interact with cells of the innate
immune system through the receptors tested. Endocytic receptors, including
the mannose receptor, DC-SIGN, langerin, and DC-SIGNR (L-SIGN), interact
predominantly with mannose-containing caps found on the mycobacterial
polysaccharide lipoarabinomannan. Some of these receptors also interact
with phosphatidyl-myo-inositol mannosides and mannose-containing
phenolic glycolipids. Many glycans are ligands for overlapping sets
of receptors, suggesting multiple, redundant routes by which mycobacteria
can enter cells. Receptors with signaling capability interact with
two distinct sets of mycobacterial glycans: targets for dectin-2 overlap
with ligands for the mannose-binding endocytic receptors, while mincle
binds exclusively to trehalose-containing structures such as trehalose
dimycolate. None of the receptors surveyed bind furanose residues,
which often form part of the epitopes recognized by antibodies to
mycobacteria. Thus, the innate and adaptive immune systems can target
different sets of mycobacterial glycans. This array, the first of
its kind, represents an important new tool for probing, at a molecular
level, biological roles of a broad range of mycobacterial glycans,
a task that has not previously been possible.
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Affiliation(s)
- Ruixiang Blake Zheng
- Department
of Chemistry and Alberta Glycomics Centre, University of Alberta, Edmonton, AB T6G 2G2, Canada
| | | | - Maju Joe
- Department
of Chemistry and Alberta Glycomics Centre, University of Alberta, Edmonton, AB T6G 2G2, Canada
| | - Yu Bai
- Department
of Chemistry and Alberta Glycomics Centre, University of Alberta, Edmonton, AB T6G 2G2, Canada
| | - Huu-Anh Tran
- Department
of Chemistry and Alberta Glycomics Centre, University of Alberta, Edmonton, AB T6G 2G2, Canada
| | - Ke Shen
- Department
of Chemistry and Alberta Glycomics Centre, University of Alberta, Edmonton, AB T6G 2G2, Canada
| | - Jörn Saupe
- Department
of Chemistry and Alberta Glycomics Centre, University of Alberta, Edmonton, AB T6G 2G2, Canada
| | - Li Xia
- Department
of Chemistry and Alberta Glycomics Centre, University of Alberta, Edmonton, AB T6G 2G2, Canada
| | - Md. Faiaz Ahmed
- Department
of Chemistry and Alberta Glycomics Centre, University of Alberta, Edmonton, AB T6G 2G2, Canada
| | - Yu-Hsuan Liu
- Department
of Chemistry and Alberta Glycomics Centre, University of Alberta, Edmonton, AB T6G 2G2, Canada
| | | | - Ashish Tripathi
- Genomics
Research Centre, Academia Sinica, Nangang, Taipei 11529, Taiwan
| | - Shang-Cheng Hung
- Genomics
Research Centre, Academia Sinica, Nangang, Taipei 11529, Taiwan
| | - Maureen E. Taylor
- Department
of Life Sciences, Imperial College, London SW7 2AZ, United Kingdom
| | - Todd L. Lowary
- Department
of Chemistry and Alberta Glycomics Centre, University of Alberta, Edmonton, AB T6G 2G2, Canada
| | - Kurt Drickamer
- Department
of Life Sciences, Imperial College, London SW7 2AZ, United Kingdom
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16
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Prados-Rosales R, Carreño L, Cheng T, Blanc C, Weinrick B, Malek A, Lowary TL, Baena A, Joe M, Bai Y, Kalscheuer R, Batista-Gonzalez A, Saavedra NA, Sampedro L, Tomás J, Anguita J, Hung SC, Tripathi A, Xu J, Glatman-Freedman A, Jacobs WR, Chan J, Porcelli SA, Achkar JM, Casadevall A. Enhanced control of Mycobacterium tuberculosis extrapulmonary dissemination in mice by an arabinomannan-protein conjugate vaccine. PLoS Pathog 2017; 13:e1006250. [PMID: 28278283 PMCID: PMC5360349 DOI: 10.1371/journal.ppat.1006250] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 03/21/2017] [Accepted: 02/17/2017] [Indexed: 12/22/2022] Open
Abstract
Currently there are a dozen or so of new vaccine candidates in clinical trials for prevention of tuberculosis (TB) and each formulation attempts to elicit protection by enhancement of cell-mediated immunity (CMI). In contrast, most approved vaccines against other bacterial pathogens are believed to mediate protection by eliciting antibody responses. However, it has been difficult to apply this formula to TB because of the difficulty in reliably eliciting protective antibodies. Here, we developed capsular polysaccharide conjugates by linking mycobacterial capsular arabinomannan (AM) to either Mtb Ag85b or B. anthracis protective antigen (PA). Further, we studied their immunogenicity by ELISA and AM glycan microarrays and protection efficacy in mice. Immunization with either Abg85b-AM or PA-AM conjugates elicited an AM-specific antibody response in mice. AM binding antibodies stimulated transcriptional changes in Mtb. Sera from AM conjugate immunized mice reacted against a broad spectrum of AM structural variants and specifically recognized arabinan fragments. Conjugate vaccine immunized mice infected with Mtb had lower bacterial numbers in lungs and spleen, and lived longer than control mice. These findings provide additional evidence that humoral immunity can contribute to protection against Mtb. Vaccine design in the TB field has been driven by the imperative of attempting to elicit strong cell-mediated responses. However, in recent decades evidence has accumulated that humoral immunity can protect against many intracellular pathogens through numerous mechanisms. In this work, we demonstrate that immunization with mycobacterial capsular arabinomannan (AM) conjugates elicited responses that contributed to protection against Mtb infection. We developed two different conjugates including capsular AM linked to the Mtb related protein Ag85b or the Mtb unrelated PA from B. anthracis and found that immunization with AM conjugates elicited antibody populations with different specificities. These surface-specific antibodies could directly modify the transcriptional profile and metabolism of mycobacteria. In addition, we observed a prolonged survival and a reduction in bacterial numbers in lungs and spleen in mice immunized with Ag85b-AM conjugates after infection with Mtb and that the presence of AM-binding antibodies was associated with modest prolongation in survival and a marked reduction in mycobacterial dissemination. Finally, we show that AM is antigenically variable and could potentially form the basis for a serological characterization of mycobacteria based on serotypes.
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Affiliation(s)
- Rafael Prados-Rosales
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx NY, United States of America
- CIC bioGUNE, Bizkaia Technology Park, Derio, Bizkaia, Spain
- * E-mail:
| | - Leandro Carreño
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx NY, United States of America
- Millennium Institute on Immunology and Immunotherapy, Programa Disciplinario de Inmunologia, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Tingting Cheng
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx NY, United States of America
- Department of Medicine, Albert Einstein College of Medicine, Bronx NY, United States of America
| | - Caroline Blanc
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx NY, United States of America
- Department of Medicine, Albert Einstein College of Medicine, Bronx NY, United States of America
| | - Brian Weinrick
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx NY, United States of America
- Howard Hughes Medical Institute, Albert Einstein College of Medicine, Bronx NY, United States of America
| | - Adel Malek
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx NY, United States of America
- Howard Hughes Medical Institute, Albert Einstein College of Medicine, Bronx NY, United States of America
| | - Todd L. Lowary
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Gunning-Lemieux Chemistry Center, Edmonton, Alberta, Canada
| | - Andres Baena
- Grupo de Inmunologia Celular e inmunogenetica, Universidad de Antioquia, Medellin, Colombia
| | - Maju Joe
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Gunning-Lemieux Chemistry Center, Edmonton, Alberta, Canada
| | - Yu Bai
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Gunning-Lemieux Chemistry Center, Edmonton, Alberta, Canada
| | - Rainer Kalscheuer
- Institute for Medical Microbiology and Hospital Hygiene, Heinrich-Heine-University Duesseldorf, Duesseldorf, Germany
| | - Ana Batista-Gonzalez
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx NY, United States of America
| | - Noemi A. Saavedra
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx NY, United States of America
| | | | - Julen Tomás
- CIC bioGUNE, Bizkaia Technology Park, Derio, Bizkaia, Spain
| | - Juan Anguita
- CIC bioGUNE, Bizkaia Technology Park, Derio, Bizkaia, Spain
- Ikerbasque, Basque Foundation for Science, Bilbao, Bizkaia, Spain
| | - Shang-Cheng Hung
- Genomics Research Center, Academia Sinica, Section 2, Nankang, Taipei, Taiwan
| | - Ashish Tripathi
- Genomics Research Center, Academia Sinica, Section 2, Nankang, Taipei, Taiwan
| | - Jiayong Xu
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx NY, United States of America
- Department of Medicine, Albert Einstein College of Medicine, Bronx NY, United States of America
| | - Aharona Glatman-Freedman
- Infectious Diseases Unit, Israel Center for Disease Control, Israel Ministry of Health, Tel Hashomer, Israel
- Department of Pediatrics, and Department of Family and Community Medicine, New York Medical College, Valhalla, NY, United States of America
| | - Williams R. Jacobs
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx NY, United States of America
- Howard Hughes Medical Institute, Albert Einstein College of Medicine, Bronx NY, United States of America
| | - John Chan
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx NY, United States of America
- Department of Medicine, Albert Einstein College of Medicine, Bronx NY, United States of America
| | - Steven A. Porcelli
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx NY, United States of America
| | - Jacqueline M. Achkar
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx NY, United States of America
- Department of Medicine, Albert Einstein College of Medicine, Bronx NY, United States of America
| | - Arturo Casadevall
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx NY, United States of America
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States of America
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17
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Chen T, Blanc C, Eder AZ, Prados-Rosales R, Souza ACO, Kim RS, Glatman-Freedman A, Joe M, Bai Y, Lowary TL, Tanner R, Brennan MJ, Fletcher HA, McShane H, Casadevall A, Achkar JM. Association of Human Antibodies to Arabinomannan With Enhanced Mycobacterial Opsonophagocytosis and Intracellular Growth Reduction. J Infect Dis 2016; 214:300-10. [PMID: 27056953 PMCID: PMC4918826 DOI: 10.1093/infdis/jiw141] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 03/30/2016] [Indexed: 01/02/2023] Open
Abstract
Background. The relevance of antibodies (Abs) in the defense against Mycobacterium tuberculosis infection remains uncertain. We investigated the role of Abs to the mycobacterial capsular polysaccharide arabinomannan (AM) and its oligosaccharide (OS) fragments in humans. Methods. Sera obtained from 29 healthy adults before and after primary or secondary bacillus Calmette-Guerin (BCG) vaccination were assessed for Ab responses to AM via enzyme-linked immunosorbent assays, and to AM OS epitopes via novel glycan microarrays. Effects of prevaccination and postvaccination sera on BCG phagocytosis and intracellular survival were assessed in human macrophages. Results. Immunoglobulin G (IgG) responses to AM increased significantly 4–8 weeks after vaccination (P < .01), and sera were able to opsonize BCG and M. tuberculosis grown in both the absence and the presence of detergent. Phagocytosis and intracellular growth inhibition were significantly enhanced when BCG was opsonized with postvaccination sera (P < .01), and these enhancements correlated significantly with IgG titers to AM (P < .05), particularly with reactivity to 3 AM OS epitopes (P < .05). Furthermore, increased phagolysosomal fusion was observed with postvaccination sera. Conclusions. Our results provide further evidence for a role of Ab-mediated immunity to tuberculosis and suggest that IgG to AM, especially to some of its OS epitopes, could contribute to the defense against mycobacterial infection in humans.
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Affiliation(s)
| | | | | | | | | | - Ryung S Kim
- Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx
| | - Aharona Glatman-Freedman
- Department of Pediatrics Department of Family and Community Medicine, New York Medical College, Valhalla, New York Infectious Diseases Unit, Israel Center for Disease Control, Israel Ministry of Health, Tel Hashomer
| | - Maju Joe
- Alberta Glycomics Centre Department of Chemistry, University of Alberta, Edmonton, Canada
| | - Yu Bai
- Alberta Glycomics Centre Department of Chemistry, University of Alberta, Edmonton, Canada
| | - Todd L Lowary
- Alberta Glycomics Centre Department of Chemistry, University of Alberta, Edmonton, Canada
| | - Rachel Tanner
- Jenner Institute, University of Oxford, United Kingdom
| | | | | | - Helen McShane
- Jenner Institute, University of Oxford, United Kingdom
| | - Arturo Casadevall
- Department of Medicine Department of Microbiology and Immunology Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
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18
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Tang XL, Wu SM, Xie Y, Song N, Guan Q, Yuan C, Zhou X, Zhang XL. Generation and application of ssDNA aptamers against glycolipid antigen ManLAM of Mycobacterium tuberculosis for TB diagnosis. J Infect 2016; 72:573-86. [PMID: 26850356 DOI: 10.1016/j.jinf.2016.01.014] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 12/20/2015] [Accepted: 01/14/2016] [Indexed: 01/01/2023]
Abstract
The development of effective Mycobacterial antigen diagnostic reagents remains a high priority. Mannose-capped lipoarabinomannan (ManLAM) is a lipoglycan serving as a major cell wall component. ManLAM is also an early released antigen in the blood circulation system during Mycobacteria tuberculosis (M.tb) infection and is a perfect target antigen for TB diagnosis. In this study, ssDNA aptamers "antibodies" against ManLAM of the predominant clinical epidemic M.tb Beijing genotype strains were generated by the Systematic Evolution of Ligands by Exponential Enrichment (SELEX) technique. The selected single aptamer T9 demonstrated the highest specificity and binding affinity, with an equilibrium dissociation constant (Kd) of 668 ± 159 nmol/L. We further detected ManLAM antigens in serum and sputum samples from active pulmonary tuberculosis (aPTB) patients, extrapulmonary TB (EPTB) patients and healthy donors by using a T9 based enzyme-linked oligonucleotide assay (ELONA). The results showed that the specificity and sensitivity were 95.31% and 83.00% (for 100 aPTB serum samples), 98.70% and 92.71% (for 96 aPTB sputum samples), and 94.44% and 88.71% (for 62 EPTB serum samples), respectively. A good correlation was observed between the T9 aptamer-based ELONA and the clinical T-SPOT.TB. Thus, T9 based ELONA has potentials for diagnosis of TB, including inactive TB, smear-negative TB, EPTB, and TB with immunodeficiency, and assist the diagnosis of LTBI albeit it could not distinguish LTBI and active TB.
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Affiliation(s)
- Xiao-Lei Tang
- State Key Laboratory of Virology and Hubei Province Key Laboratory of Allergy and Immunology, Medical Research Institute, and Department of Immunology, Wuhan University School of Medicine, Donghu Road 165#, Wuhan 430071, Hubei Province, China; Department of Clinical Laboratory, the Second Hospital of Wuhu, Wuhu 241000, Anhui Province, China
| | - Shi-Min Wu
- State Key Laboratory of Virology and Hubei Province Key Laboratory of Allergy and Immunology, Medical Research Institute, and Department of Immunology, Wuhan University School of Medicine, Donghu Road 165#, Wuhan 430071, Hubei Province, China; Wuhan Center for Clinical Laboratory, Puai Hospital, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Yan Xie
- State Key Laboratory of Virology and Hubei Province Key Laboratory of Allergy and Immunology, Medical Research Institute, and Department of Immunology, Wuhan University School of Medicine, Donghu Road 165#, Wuhan 430071, Hubei Province, China
| | - Neng Song
- State Key Laboratory of Virology and Hubei Province Key Laboratory of Allergy and Immunology, Medical Research Institute, and Department of Immunology, Wuhan University School of Medicine, Donghu Road 165#, Wuhan 430071, Hubei Province, China
| | - Qing Guan
- State Key Laboratory of Virology and Hubei Province Key Laboratory of Allergy and Immunology, Medical Research Institute, and Department of Immunology, Wuhan University School of Medicine, Donghu Road 165#, Wuhan 430071, Hubei Province, China
| | - Chunhui Yuan
- State Key Laboratory of Virology and Hubei Province Key Laboratory of Allergy and Immunology, Medical Research Institute, and Department of Immunology, Wuhan University School of Medicine, Donghu Road 165#, Wuhan 430071, Hubei Province, China
| | - Xiang Zhou
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei Province, China
| | - Xiao-Lian Zhang
- State Key Laboratory of Virology and Hubei Province Key Laboratory of Allergy and Immunology, Medical Research Institute, and Department of Immunology, Wuhan University School of Medicine, Donghu Road 165#, Wuhan 430071, Hubei Province, China.
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Haji-Ghassemi O, Blackler RJ, Martin Young N, Evans SV. Antibody recognition of carbohydrate epitopes†. Glycobiology 2015; 25:920-52. [PMID: 26033938 DOI: 10.1093/glycob/cwv037] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 05/24/2015] [Indexed: 12/14/2022] Open
Abstract
Carbohydrate antigens are valuable as components of vaccines for bacterial infectious agents and human immunodeficiency virus (HIV), and for generating immunotherapeutics against cancer. The crystal structures of anti-carbohydrate antibodies in complex with antigen reveal the key features of antigen recognition and provide information that can guide the design of vaccines, particularly synthetic ones. This review summarizes structural features of anti-carbohydrate antibodies to over 20 antigens, based on six categories of glyco-antigen: (i) the glycan shield of HIV glycoproteins; (ii) tumor epitopes; (iii) glycolipids and blood group A antigen; (iv) internal epitopes of bacterial lipopolysaccharides; (v) terminal epitopes on polysaccharides and oligosaccharides, including a group of antibodies to Kdo-containing Chlamydia epitopes; and (vi) linear homopolysaccharides.
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Affiliation(s)
- Omid Haji-Ghassemi
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada V8P 3P6
| | - Ryan J Blackler
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada V8P 3P6
| | - N Martin Young
- Human Health Therapeutics, National Research Council of Canada, 100 Sussex Drive, Ottawa, ON, Canada K1A 0R6
| | - Stephen V Evans
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada V8P 3P6
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20
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The diagnostic targeting of a carbohydrate virulence factor from M.Tuberculosis. Sci Rep 2015; 5:10281. [PMID: 25975873 PMCID: PMC4432570 DOI: 10.1038/srep10281] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 03/17/2015] [Indexed: 11/25/2022] Open
Abstract
The current clinical management of TB is complicated by the lack of suitable diagnostic tests that can be employed in infrastructure and resource poor regions. The mannose-capped form of lipoarabinomannan (ManLAM) is unique to the surface envelope of slow-growing, pathogenic mycobacteria such as M.tuberculosis (M.tb) and facilitates passive invasion of mononuclear phagocytes. The detection of this virulence factor in urine, sputum and serum has engendered interest in its employment as a biomarker for M.tb infection. In this study, we utilize a subtractive screening methodology to engineer the first high affinity recombinant antibody (My2F12) with exquisite specificity for the α1-2 mannose linkages enriched in ManLAM from M.tb. My2F12 binds to pathogenic mycobacterial species but not fast growing non-pathogenic species. Testing on matched urine and serum samples from TB patients indicates that My2F12 works in patient cohorts missed by other diagnostic methodologies.
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21
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Mandal PK, Chheda PR. Synthesis and biotinylation of oligosaccharide fragments of mannosylated and 5-deoxy-5-methylthio-xylofuranosylated lipoarabinomannan from Mycobacterium tuberculosis. Carbohydr Res 2015; 407:104-10. [DOI: 10.1016/j.carres.2015.01.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Revised: 01/06/2015] [Accepted: 01/11/2015] [Indexed: 10/24/2022]
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22
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Lak P, Makeneni S, Woods RJ, Lowary TL. Specificity of furanoside-protein recognition through antibody engineering and molecular modeling. Chemistry 2014; 21:1138-48. [PMID: 25413161 DOI: 10.1002/chem.201405259] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2014] [Indexed: 01/06/2023]
Abstract
Recognition of furanosides (five-membered ring sugars) by proteins plays important roles in host-pathogen interactions. In comparison to their six-membered ring counterparts (pyranosides), detailed studies of the molecular motifs involved in the recognition of furanosides by proteins are scarce. Here the first in-depth molecular characterization of a furanoside-protein interaction system, between an antibody (CS-35) and cell wall polysaccharides of mycobacteria, including the organism responsible for tuberculosis is reported. The approach was centered on the generation of the single chain variable fragment of CS-35 and a rational library of its mutants. Investigating the interaction from various aspects revealed the structural motifs that govern the interaction, as well as the relative contribution of molecular forces involved in the recognition. The specificity of the recognition was shown to originate mainly from multiple CH-π interactions and, to a lesser degree, hydrogen bonds formed in critical distances and geometries.
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Affiliation(s)
- Parnian Lak
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, AB, T6G 2G2 (Canada)
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23
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Korkegian A, Roberts DM, Blair R, Parish T. Mutations in the essential arabinosyltransferase EmbC lead to alterations in Mycobacterium tuberculosis lipoarabinomannan. J Biol Chem 2014; 289:35172-81. [PMID: 25352598 DOI: 10.1074/jbc.m114.583112] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Mycobacterium tuberculosis cell wall is a complex structure essential for the viability of the organism and its interaction with the host. The glycolipid lipoarabinomannan (LAM) plays an important role in mediating host-bacteria interactions and is involved in modulation of the immune response. The arabinosyltransferase EmbC required for LAM biosynthesis is essential. We constructed recombinant strains of M. tuberculosis expressing a variety of alleles of EmbC. We demonstrated that EmbC has a functional signal peptide in M. tuberculosis. Over- or underexpression of EmbC resulted in reduced or increased sensitivity to ethambutol, respectively. The C-terminal domain of EmbC was essential for activity because truncated alleles were unable to mediate LAM production in Mycobacterium smegmatis and were unable to complement an embC deletion in M. tuberculosis. The C-terminal domain of the closely related arabinosyltransferase EmbB was unable to complement the function of the EmbC C-terminal domain. Two functional motifs were identified. The GT-C motif contains two aspartate residues essential for function in the DDX motif. The proline-rich region contains two highly conserved asparagines (Asn-638 and Asn-652). Mutation of these residues was tolerated, but loss of Asn-638 resulted in the synthesis of truncated LAM, which appeared to lack arabinose branching. All embC alleles that were incapable of complementing LAM production in M. smegmatis were not viable in M. tuberculosis, supporting the hypothesis that LAM itself is essential in M. tuberculosis.
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Affiliation(s)
- Aaron Korkegian
- From TB Discovery Research, Infectious Disease Research Institute, Seattle, Washington 98102
| | - David M Roberts
- From TB Discovery Research, Infectious Disease Research Institute, Seattle, Washington 98102
| | - Rachel Blair
- From TB Discovery Research, Infectious Disease Research Institute, Seattle, Washington 98102
| | - Tanya Parish
- From TB Discovery Research, Infectious Disease Research Institute, Seattle, Washington 98102
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24
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Bothamley GH. Epitope-specific antibody levels in tuberculosis: biomarkers of protection, disease, and response to treatment. Front Immunol 2014; 5:243. [PMID: 24917863 PMCID: PMC4040437 DOI: 10.3389/fimmu.2014.00243] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2014] [Accepted: 05/09/2014] [Indexed: 12/04/2022] Open
Abstract
Monoclonal antibodies restricted to Mycobacterium tuberculosis can measure epitope-specific antibody levels in a competition assay. Immunodominant epitopes were defined from clinical samples and related to the clinical spectrum of disease. Antibody to the immunodominant epitopes was associated with HLA-DR15. Occupational exposure showed a different response and was consistent with recognition of dormancy-related proteins and protection despite exposure to tuberculosis (TB). Studies in leprosy revealed the importance of immune deviation and the relationships between T and B cell epitopes. During treatment, antibody levels increased, epitope spreading occurred, but the affinity constants remained the same after further antigen exposure, suggesting constraints on the process of epitope selection. Epitope-specific antibody levels have a potential role as biomarkers for new vaccines which might prevent the progression of latent to active TB and as tools to measure treatment effects on subpopulations of tubercle bacilli.
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Affiliation(s)
- Graham H Bothamley
- Department of Respiratory Medicine, Homerton University Hospital , London , UK
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25
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Chlubnová I, Králová B, Dvořáková H, Hošek P, Spiwok V, Filipp D, Nugier-Chauvin C, Daniellou R, Ferrières V. The versatile enzyme Araf51 allowed efficient synthesis of rare pathogen-related β-d-galactofuranosyl-pyranoside disaccharides. Org Biomol Chem 2014; 12:3080-9. [DOI: 10.1039/c3ob42519c] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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26
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Yang L, Sinha T, Carlson TK, Keiser TL, Torrelles JB, Schlesinger LS. Changes in the major cell envelope components of Mycobacterium tuberculosis during in vitro growth. Glycobiology 2013; 23:926-34. [PMID: 23576535 PMCID: PMC3695751 DOI: 10.1093/glycob/cwt029] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 04/03/2013] [Accepted: 04/07/2013] [Indexed: 12/15/2022] Open
Abstract
One-third of the world's population is infected with Mycobacterium tuberculosis (M.tb), which causes tuberculosis. Mycobacterium tuberculosis cell envelope components such as glycolipids, lipoglycans and polysaccharides play important roles in bacteria-host cell interactions that dictate the host immune response. However, little is known about the changes in the amounts and types of these cell envelope components as the bacillus divides during in vitro culture. To shed light on these phenomena, we examined growth-dependent changes over time in major cell envelope components of virulent M.tb by using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, thin-layer chromatography, mass spectrometry, immunoblotting and flow cytometry. Our studies provide evidence that major mannosylated glycoconjugates on the M.tb cell envelope change as M.tb grows in vitro on the widely used Middlebrook 7H11 agar. In particular, our compositional analyses show that from Day 9 to 28 the amounts of mannose-containing molecules, such as mannose-capped lipoarabinomannan, lipomannan and phosphatidyl-myo-inositol mannosides, change continuously in both the cell envelope and outer cell surface. Along with these changes, mannan levels on the outer cell surface also increase significantly over time. The implications of these differences in terms of how M.tb is grown for studies performed in vitro and in vivo for assessing M.tb-host recognition and establishment of infection are discussed.
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Affiliation(s)
- Lanhao Yang
- Department of Microbial Infection and Immunity, Center for Microbial Interface Biology
| | - Tejas Sinha
- Department of Microbial Infection and Immunity, Center for Microbial Interface Biology
| | - Tracy K Carlson
- Department of Microbial Infection and Immunity, Center for Microbial Interface Biology
- Department of Veterinary Biosciences
| | - Tracy L Keiser
- Department of Microbial Infection and Immunity, Center for Microbial Interface Biology
- Department of Microbiology, The Ohio State University, 460 W. 12th Avenue, Biomedical Research Tower, Columbus, OH 43210, USA
| | - Jordi B Torrelles
- Department of Microbial Infection and Immunity, Center for Microbial Interface Biology
| | - Larry S Schlesinger
- Department of Microbial Infection and Immunity, Center for Microbial Interface Biology
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27
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Hiatt LA, Cliffel DE. Real-time Recognition of Mycobacterium tuberculosis and Lipoarabinomannan using the Quartz Crystal Microbalance. SENSORS AND ACTUATORS. B, CHEMICAL 2012; 174:245-252. [PMID: 23175600 PMCID: PMC3500912 DOI: 10.1016/j.snb.2012.06.095] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A quartz crystal microbalance (QCM) immunosensor has been successfully employed to screen for both whole Mycobacteria tuberculosis (Mtb) bacilli and a Mtb surface antigen, lipoarabinomannan (LAM). One of the most abundant components of the Mtb cell surface, LAM, may be detected without the presence of the entire bacterium. Using available antibodies with proven utility in enzyme-linked immunoassays (ELISAs), a sensor was designed to measure Mtb bacilli and LAM. Equilibrium association constants (K(a)) were determined for the interaction of Mtb with immobilized α-LAM and anti-H37Rv antibodies, where avidity was seen to strengthen this interaction and provide for greater binding than might have otherwise been achieved. The binding of LAM to immobilized α-LAM had a high associate rate constant (k(a)) allowing for rapid detection. Evaluating these binding constants helped the compare the sensitivity of these immunosensors to conventional ELISAs. The use of these assays with the better antibodies may allow for immunosensor use in determining LAM as a point-of-care (POC) diagnostic for Mtb.
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Affiliation(s)
- Leslie A. Hiatt
- Department of Chemistry, Vanderbilt University, 7330 Stevenson Center, VU Station B 351822, Nashville, TN 37235-1822 USA
| | - David E. Cliffel
- Department of Chemistry, Vanderbilt University, 7330 Stevenson Center, VU Station B 351822, Nashville, TN 37235-1822 USA
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28
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Torrelles JB, Sieling PA, Zhang N, Keen MA, McNeil MR, Belisle JT, Modlin RL, Brennan PJ, Chatterjee D. Isolation of a distinct Mycobacterium tuberculosis mannose-capped lipoarabinomannan isoform responsible for recognition by CD1b-restricted T cells. Glycobiology 2012; 22:1118-27. [PMID: 22534567 PMCID: PMC3382347 DOI: 10.1093/glycob/cws078] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Revised: 04/17/2012] [Accepted: 04/19/2012] [Indexed: 12/23/2022] Open
Abstract
Mannose-capped lipoarabinomannan (ManLAM) is a complex lipoglycan abundantly present in the Mycobacterium tuberculosis cell envelope. Many biological properties have been ascribed to ManLAM, from directly interacting with the host and participating in the intracellular survival of M. tuberculosis, to triggering innate and adaptive immune responses, including the activation of CD1b-restricted T cells. Due to its structural complexity, ManLAM is considered a heterogeneous population of molecules which may explain its different biological properties. The presence of various modifications such as fatty acids, succinates, lactates, phosphoinositides and methylthioxylose in ManLAM have proven to correlate directly with its biological activity and may potentially be involved in the interactions between CD1b and the T cell population. To further delineate the specific ManLAM epitopes involved in CD1b-restricted T cell recognition, and their potential roles in mediating immune responses in M. tuberculosis infection, we established a method to resolve ManLAM into eight different isoforms based on their different isoelectric values. Our results show that a ManLAM isoform with an isoelectric value of 5.8 was the most potent in stimulating the production of interferon-γ in different CD1b-restricted T-cell lines. Compositional analyses of these isoforms of ManLAM revealed a direct relationship between the overall charge of the ManLAM molecule and its capacity to be presented to T cells via the CD1 compartment.
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Affiliation(s)
- Jordi B Torrelles
- Mycobacterial Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA.
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29
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Sarkar S, Tang XL, Das D, Spencer JS, Lowary TL, Suresh MR. A bispecific antibody based assay shows potential for detecting tuberculosis in resource constrained laboratory settings. PLoS One 2012; 7:e32340. [PMID: 22363820 PMCID: PMC3283739 DOI: 10.1371/journal.pone.0032340] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Accepted: 01/27/2012] [Indexed: 11/30/2022] Open
Abstract
The re-emergence of tuberculosis (TB) as a global public health threat highlights the necessity of rapid, simple and inexpensive point-of-care detection of the disease. Early diagnosis of TB is vital not only for preventing the spread of the disease but also for timely initiation of treatment. The later in turn will reduce the possible emergence of multi-drug resistant strains of Mycobacterium tuberculosis. Lipoarabinomannan (LAM) is an important non-protein antigen of the bacterial cell wall, which is found to be present in different body fluids of infected patients including blood, urine and sputum. We have developed a bispecific monoclonal antibody with predetermined specificities towards the LAM antigen and a reporter molecule horseradish peroxidase (HRPO). The developed antibody was subsequently used to design a simple low cost immunoswab based assay to detect LAM antigen. The limit of detection for spiked synthetic LAM was found to be 5.0 ng/ml (bovine urine), 0.5 ng/ml (rabbit serum) and 0.005 ng/ml (saline) and that for bacterial LAM from M. tuberculosis H37Rv was found to be 0.5 ng/ml (rabbit serum). The assay was evaluated with 21 stored clinical serum samples (14 were positive and 7 were negative in terms of anti-LAM titer). In addition, all 14 positive samples were culture positive. The assay showed 100% specificity and 64% sensitivity (95% confidence interval). In addition to good specificity, the end point could be read visually within two hours of sample collection. The reported assay might be used as a rapid tool for detecting TB in resource constrained laboratory settings.
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Affiliation(s)
- Susmita Sarkar
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Xinli L. Tang
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Dipankar Das
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - John S. Spencer
- Departments of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Todd L. Lowary
- Department of Chemistry and Alberta Ingenuity Centre for Carbohydrate Science, University of Alberta, Edmonton, Alberta, Canada
| | - Mavanur R. Suresh
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
- * E-mail:
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30
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Obregón-Henao A, Duque-Correa MA, Rojas M, García LF, Brennan PJ, Ortiz BL, Belisle JT. Stable extracellular RNA fragments of Mycobacterium tuberculosis induce early apoptosis in human monocytes via a caspase-8 dependent mechanism. PLoS One 2012; 7:e29970. [PMID: 22253841 PMCID: PMC3253812 DOI: 10.1371/journal.pone.0029970] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Accepted: 12/10/2011] [Indexed: 01/24/2023] Open
Abstract
The molecular basis of pathogen-induced host cell apoptosis is well characterized for a number of microorganisms. Mycobacterium tuberculosis is known to induce apoptosis and it was shown that live but not heat killed M. tuberculosis stimulates this biological pathway in monocytes. The dependence of this activity on live bacilli led us to hypothesize that products released or secreted by M. tuberculosis are the primary apoptotic factors for human monocytes. Thus, the culture filtrate of in vitro grown M. tuberculosis strain H37Rv was fractioned by conventional chromatography and the apoptosis-inducing activity of individual fractions was measured on human monocytes. The tests employed included measurement of cell membrane damage, caspase activation, and cytokine release. Small molecular weight RNAs of M. tuberculosis were recognized as the predominant apoptosis inducing factors. The RNA was comprised primarily of tRNA and rRNA fragments that stably accumulate in the culture filtrate during early log-phase growth. The RNA fragments signaled through a caspase-8 dependent, caspase-1 and TNF-α independent pathway that ultimately compromised the human monocytes' ability to control M. tuberculosis infection. These studies provide the first report of bacterial RNA inducing apoptosis. They also provide a foundation to pursue pathways for secretion or release of nucleic acids from M. tuberculosis and the impact of secreted RNA fragments on pathogenesis.
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Affiliation(s)
- Andrés Obregón-Henao
- Grupo de Inmunología Celular e Inmunogenética, Universidad de Antioquia, Medellín, Colombia
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - María A. Duque-Correa
- Grupo de Inmunología Celular e Inmunogenética, Universidad de Antioquia, Medellín, Colombia
| | - Mauricio Rojas
- Grupo de Inmunología Celular e Inmunogenética, Universidad de Antioquia, Medellín, Colombia
| | - Luis F. García
- Grupo de Inmunología Celular e Inmunogenética, Universidad de Antioquia, Medellín, Colombia
| | - Patrick J. Brennan
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Blanca L. Ortiz
- Grupo de Inmunología Celular e Inmunogenética, Universidad de Antioquia, Medellín, Colombia
| | - John T. Belisle
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
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Gadikota RR, Callam CS, Appelmelk BJ, Lowary TL. Synthesis of Oligosaccharide Fragments of Mannosylated Lipoarabinomannan Appropriately Functionalized for Neoglycoconjugate Preparation. J Carbohydr Chem 2011. [DOI: 10.1081/car-120021696] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
| | - Christopher S. Callam
- a Department of Chemistry , Ohio State University , 100 West 18th Avenue, Columbus , OH , 43210 , USA
| | - Ben J. Appelmelk
- b Department of Medical Microbiology , Medical School , Vrije University , van der Boechorststraat 7, 1081 BT , Amsterdam , The Netherlands
| | - Todd L. Lowary
- a Department of Chemistry , Ohio State University , 100 West 18th Avenue, Columbus , OH , 43210 , USA
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32
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Zhang J, Zhou X. Novel 3-dimensional dendrimer platform for glycolipid microarray. Biosens Bioelectron 2011; 28:355-61. [PMID: 21820887 PMCID: PMC3163748 DOI: 10.1016/j.bios.2011.07.044] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2011] [Revised: 07/04/2011] [Accepted: 07/18/2011] [Indexed: 12/11/2022]
Abstract
Glycolipids are important biological molecules that modulate cellular recognitions and pathogen adhesions. In this paper, we report a sensitive glycolipid microarray for non-covalently immobilizing glycolipids on a microarray substrate and we perform a set of immunoassays to explore glycolipid-protein interactions. This substrate utilizes a three-dimensional hydrazide-functionalized dendrimer monolayer attached onto a microscopic glass surface, which possesses the characteristics to adsorb glycoliplids non-covalently and facilitates multivalent attributes on the substrate surface. In the proof-of-concept experiments, gangliosides such as GM1, FucGM1, GM3, GD1b, GT1b, and GQ1b, and a lipoarabinomannan were tested on the substrate and interrogated with toxins and antibodies. The resulting glycolipid microarrays exhibited hypersensitivity and specificity for detection of glycolipid-protein interactions. In particular, a robust and specific binding of a pentameric cholera toxin B subunit to the GM1 glycolipid spotted on the array has demonstrated its superiority in sensitivity and specificity. In addition, this glycolipid microarray substrate was used to detect lipoarabinomannan in buffer within a limit-of-detection of 125 ng/mL. Furthermore, Mycobacterium tuberculosis (Mtb) Lipoarabinomannan was tested in human urine specimens on this platform, which can effectively identify urine samples either infected or not infected with Mtb. The results of this work suggest the possibility of using this glycolipid microarray platform to fabricate glycoconjugate microarrays, which includes free glycans and glycolipids and potential application in detection of pathogen and toxin.
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Affiliation(s)
- Jian Zhang
- ADA Technologies Inc., 8100 Shaffer Parkway, Suite 130, Littleton, CO 80127, USA.
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Arcos J, Sasindran SJ, Fujiwara N, Turner J, Schlesinger LS, Torrelles JB. Human lung hydrolases delineate Mycobacterium tuberculosis-macrophage interactions and the capacity to control infection. THE JOURNAL OF IMMUNOLOGY 2011; 187:372-81. [PMID: 21602490 DOI: 10.4049/jimmunol.1100823] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Pulmonary surfactant contains homeostatic and antimicrobial hydrolases. When Mycobacterium tuberculosis is initially deposited in the terminal bronchioles and alveoli, as well as following release from lysed macrophages, bacilli are in intimate contact with these lung surfactant hydrolases. We identified and measured several hydrolases in human alveolar lining fluid and lung tissue that, at their physiological concentrations, dramatically modified the M. tuberculosis cell envelope. Independent of their action time (15 min to 12 h), the effects of the hydrolases on the M. tuberculosis cell envelope resulted in a significant decrease (60-80%) in M. tuberculosis association with, and intracellular growth of the bacteria within, human macrophages. The cell envelope-modifying effects of the hydrolases also led to altered M. tuberculosis intracellular trafficking and induced a protective proinflammatory response to infection. These findings add a new concept to our understanding of M. tuberculosis-macrophage interactions (i.e., the impact of lung surfactant hydrolases on M. tuberculosis infection).
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Affiliation(s)
- Jesús Arcos
- Center for Microbial Interface Biology, The Ohio State University, Columbus, OH 43210, USA
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Synthesis of covalent conjugates of hexaarabinofuranoside with proteins and their testing as antigens for serodiagnosis of tuberculosis. Russ Chem Bull 2011. [DOI: 10.1007/s11172-010-0397-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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35
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Abronina PI, Sedinkin SL, Podvalnyy NM, Fedina KG, Zinin AI, Torgov VI, Kononov LO. Formation of orthoester-linked d-arabinofuranose oligosaccharides and their isomerization into the corresponding glycosides. Tetrahedron Lett 2011. [DOI: 10.1016/j.tetlet.2011.02.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Zhang J, Amin AG, Hölemann A, Seeberger PH, Chatterjee D. Development of a plate-based scintillation proximity assay for the mycobacterial AftB enzyme involved in cell wall arabinan biosynthesis. Bioorg Med Chem 2010; 18:7121-31. [PMID: 20800502 DOI: 10.1016/j.bmc.2010.07.040] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2010] [Revised: 07/13/2010] [Accepted: 07/16/2010] [Indexed: 01/03/2023]
Abstract
A number of mycobacterial arabinosyltransferases, such as the Emb proteins, AftA, AftB, AftC, and AftD have been characterized and implicated to be involved in the cell wall arabinan assembly. These arabinosyltransferases are essential for the viability of the organism and are logically valid targets for developing new anti-tuberculosis agents. For instance, Ethambutol, a first line anti-tuberculosis drug, targets the Emb proteins involved in the formation of the arabinan of cell wall arabinogalactan. Among these arabinosyltransferases, the terminal β-(1→2) arabinosyltransferase activity has been associated with AftB. The predicted topology of AftB in Mycobacterium tuberculosis has 10 N terminal transmembrane domains and a C terminal hydrophilic domain similar to the Emb proteins. It has a conserved GT-C motif and is difficult to express. In a cell free assay, synthetic disaccharide, α-D-Araf-(1→5)-α-D-Araf-octyl, has been used as a substrate to explore the function of AftB. In our work, the disaccharide was synthesized in its pentenylated and biotinylated form, and the enzymatic product formed was identified as the β-(1→2) arabinofuranose adduct. When synthetic tri- and tetra-saccharides were used as substrates, a mixture of products containing both β-(1→2) and α-(1→5) linkages were formed. Therefore, the biotinylated disaccharide was selected to develop a scintillation proximity assay.
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Affiliation(s)
- Jian Zhang
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA.
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Cao B, Williams SJ. Chemical approaches for the study of the mycobacterial glycolipids phosphatidylinositol mannosides, lipomannan and lipoarabinomannan. Nat Prod Rep 2010; 27:919-47. [DOI: 10.1039/c000604a] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Tam PH, Lowary TL. Epimeric and amino disaccharide analogs as probes of an alpha-(1-->6)-mannosyltransferase involved in mycobacterial lipoarabinomannan biosynthesis. Org Biomol Chem 2009; 8:181-92. [PMID: 20024149 DOI: 10.1039/b916580k] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Mycobacterial lipoarabinomannan (LAM) is an important, immunologically active glycan found in the cell wall of mycobacteria, including the human pathogen Mycobacterium tuberculosis. At the core of LAM is a mannan domain comprised of alpha-(1-->6)-linked-mannopyranose (Manp) residues. Previously, we and others have demonstrated that alpha-Manp-(1-->6)-alpha-Manp disaccharides (e.g., Manp-(1-->6)-alpha-ManpOctyl, ) are the minimum acceptor substrates for enzymes involved in the assembly of the LAM mannan core. We report here the synthesis five epimeric and three amino analogs of , and their subsequent biochemical evaluation against an alpha-(1-->6)-ManT activity present in a membrane preparation from M. smegmatis. Changing the manno- configuration of either residue of to talo- or gluco- led to a reduction or loss of activity, thus confirming earlier work showing that the C-2 and C-4 hydroxyl groups of each monosaccharide were important for enzymatic recognition. Characterization of the products formed from these analogs was done using a combination of mass spectrometry and glycosidase digestion, and full substrate kinetics were also performed. The analogs in which the acceptor hydroxyl group had been replaced with an amino group were, as expected, not substrates for the enzyme, but were weak inhibitors.
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Affiliation(s)
- Pui Hang Tam
- Alberta Ingenuity Centre for Carbohydrate Science and Department of Chemistry, The University of Alberta, Gunning-Lemieux Chemistry Centre, Edmonton, AB T6G 2G2, Canada
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Murase T, Zheng RB, Joe M, Bai Y, Marcus SL, Lowary TL, Ng KK. Structural Insights into Antibody Recognition of Mycobacterial Polysaccharides. J Mol Biol 2009; 392:381-92. [DOI: 10.1016/j.jmb.2009.06.074] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Revised: 06/26/2009] [Accepted: 06/29/2009] [Indexed: 10/20/2022]
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Shi L, Torrelles JB, Chatterjee D. Lipoglycans of Mycobacterium tuberculosis: isolation, purification, and characterization. Methods Mol Biol 2009; 465:23-45. [PMID: 20560059 DOI: 10.1007/978-1-59745-207-6_3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
In this chapter, we describe in detail the steps involved in isolation and characterization of lipoglycans from Mycobacterium tuberculosis and Mycobacterium smegmatis. In addition, procedures involved in structural analysis such as immunoblotting with mAb CS-35 or CS-40, gas chromatography, gas chromatography/mass spectrometry, nuclear magnetic resonance spectroscopy, and endoarabinanase digestion followed by high-pH anion exchange chromatography and two-dimensional gel electrophoresis are presented.
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Affiliation(s)
- Libin Shi
- Department of Microbiology, Colorado State University, Fort Collins, Colorado 80523, USA
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41
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Lipoarabinomannan of Mycobacterium: mannose capping by a multifunctional terminal mannosyltransferase. Proc Natl Acad Sci U S A 2008; 105:17973-7. [PMID: 19004785 DOI: 10.1073/pnas.0807761105] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Biosynthesis of phosphatidylinositol (PI)-containing lipoarabinomannan (LAM) and lipomannan (LM) of Mycobacterium spp. follows a conserved pathway involving multiple membrane-associated, substrate-specific mannosyltransferases (ManTs) responsible for the sequential addition of alpha-mannopyranosyl (Manp) units donated by decaprenyl-P-Manp on the periplasmic side of the plasma membrane. Because of their receptor-binding and immunomodulatory properties, the alpha(1-->2)-linked di- and tri-Manp motifs that functionalize the nonreducing arabinan termini of LAM (ManLAM) in Mycobacterium tuberculosis are of crucial importance. We now show that the M. tuberculosis ManT, Rv2181, is required for the addition of these alpha(1-->2)-linked Manp residues but also at other locations of the LAM molecule. Structural analyses of the LM and LAM variants produced by a M. tuberculosis Rv2181 knockout mutant revealed the presence of but a single Manp residue on the nonreducing arabinan termini of LAM and also a complete absence of alpha(1-->2)-linked Man branching on the mannan backbones of LM and LAM. A recombinant strain was constructed in ManLAM-deficient Mycobacterium smegmatis that coexpressed Rv2181 and Rv1635c-the ManT responsible for the addition of the first Manp capping residue of ManLAM. Analysis revealed LAM termini fully capped with di- and tri-Manp motifs in addition to alpha(1-->2)Man branching on the mannan backbones of LM and LAM, confirming the involvement of the alpha(1-->2)ManT Rv2181 in the dual role of Man capping and mannan-core branching, and in the process generated a rapidly growing, ManLAM-containing strain, a tool for the study of the role of ManLAM in the pathogenesis of tuberculosis.
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Torrelles JB, Knaup R, Kolareth A, Slepushkina T, Kaufman TM, Kang P, Hill PJ, Brennan PJ, Chatterjee D, Belisle JT, Musser JM, Schlesinger LS. Identification of Mycobacterium tuberculosis clinical isolates with altered phagocytosis by human macrophages due to a truncated lipoarabinomannan. J Biol Chem 2008; 283:31417-28. [PMID: 18784076 DOI: 10.1074/jbc.m806350200] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Phenotypically distinct clinical isolates of Mycobacterium tuberculosis are capable of altering the balance that exists between the pathogen and human host and ultimately the outcome of infection. This study has identified two M. tuberculosis strains (i.e. HN885 and HN1554) among a bank of clinical isolates with a striking defect in phagocytosis by primary human macrophages when compared with strain Erdman, a commonly used laboratory strain for studies of pathogenesis. Mass spectrometry in conjunction with NMR studies unequivocally confirmed that both HN885 and HN1554 contain truncated and more branched forms of mannose-capped lipoarabinomannan (ManLAM) with a marked reduction of their linear arabinan (corresponding mainly to the inner Araf-alpha(1-->5)-Araf unit) and mannan (with fewer 6-Manp residues and more substitutions in the linear Manp-alpha(1-->6)-Manp unit) domains. The truncation in the ManLAM molecules produced by strains HN885 and HN1554 led to a significant reduction in their surface availability. In addition, there was a marked reduction of higher order phosphatidyl-myo-inositol mannosides and the presence of dimycocerosates, triglycerides, and phenolic glycolipid in their cell envelope. Less exposed ManLAM and reduced higher order phosphatidyl-myo-inositol mannosides in strains HN885 and HN1554 resulted in their low association with the macrophage mannose receptor. Despite reduced phagocytosis, ingested bacilli replicated at a fast rate following serum opsonization. Our results provide evidence that the clinical spectrum of tuberculosis may be dictated not only by the host but also by the amounts and ratios of surface exposed mycobacterial adherence factors defined by strain genotype.
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Affiliation(s)
- Jordi B Torrelles
- Center for Microbial Interface Biology, Division of Infectious Diseases, Department of Internal Medicine, Ohio State University, Columbus, Ohio 43210, USA
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Kaur D, McNeil MR, Khoo KH, Chatterjee D, Crick DC, Jackson M, Brennan PJ. New insights into the biosynthesis of mycobacterial lipomannan arising from deletion of a conserved gene. J Biol Chem 2007; 282:27133-27140. [PMID: 17606615 DOI: 10.1074/jbc.m703389200] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Genetic construction of a mutant strain (designated MSMEG4245) of Mycobacterium smegmatis, defective in a broadly conserved gene for a putative glycosyltransferase of the glycosyltransferase-C superfamily, results in a phenotype marked by the virtual absence of the phosphatidylinositol-containing lipomannan and lipoarabinomannan, replaced instead by a novel truncated form of lipomannan. The normal spectrum of phosphatidylinositol mannosides, long presumed precursors of these lipoglycans, was retained. Matrix-assisted laser desorption/ionization-time of flight/mass spectrometry of the mutated form of lipomannan shows a family of phosphatidylinositol-anchored lipomannans with from only 5 to 20 Manp residues as compared with lipomannan from the wild type strain consisting of 21-34 Manp residues but with few changes in the branching pattern. Thus, MSMEG4245 is apparently a key mannosyltransferase, required for the proper elongation of lipomannan to its normal state and subsequent synthesis of lipoarabinomannan. The corresponding ortholog in Mycobacterium tuberculosis H37Rv has been identified as Rv2174. This previously unrecognized feature of the biosynthesis of lipomannan/lipoarabinomannan allows a significant revision of structural and biosynthetic schemata and provides a molecular basis of selectivity in biosynthesis, as conferred by the MSMEG4245 gene.
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Affiliation(s)
- Devinder Kaur
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, 80523, the
| | - Michael R McNeil
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, 80523, the
| | - Kay-Hooi Khoo
- Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan, and the
| | - Delphi Chatterjee
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, 80523, the
| | - Dean C Crick
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, 80523, the
| | - Mary Jackson
- Unite de Genetique Mycobacterienne, Institut Pasteur, 25 rue du Dr. Roux, 75724 Paris Cedex 15, France
| | - Patrick J Brennan
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, 80523, the.
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Barenholz A, Hovav AH, Fishman Y, Rahav G, Gershoni JM, Bercovier H. A peptide mimetic of the mycobacterial mannosylated lipoarabinomannan: characterization and potential applications. J Med Microbiol 2007; 56:579-586. [PMID: 17446277 DOI: 10.1099/jmm.0.46920-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Mannosylated lipoarabinomannan (ManLAM), a complex lipoglycan, is a major component of Mycobacterium tuberculosis, the agent of tuberculosis (TB), and is an antigen used for serological diagnosis of TB. Screening random phage-display peptide libraries with anti-ManLAM mAb CS40 for peptide epitope mimics (mimotopes) led to the isolation of a panel of peptides. One of these peptides (B11) was characterized as a ManLAM mimotope: it bound the anti-ManLAM CS40 mAb and competed with ManLAM for antibody binding. Mice immunized with keyhole limpet haemocyanin-conjugated B11 peptide in a proper adjuvant developed antibodies that recognized ManLAM. Competition experiments demonstrated that the B11 peptide inhibited binding of mAb CS40 to ManLAM in a concentration-dependent manner. The data indicated that the affinity of CS40 mAb to B11 (K(D) 1.33 x 10(-8)) is higher than its affinity to ManLAM (K(D) 3.00 x 10(-7)). The sera of TB patients, as well as the sera of mice experimentally infected with M. tuberculosis, contained significant levels of antibodies that recognized both the B11 peptide and ManLAM. The specificity and sensitivity of the ELISA B11-based test were similar to those of the ELISA ManLAM-based test, indicating that the B11 antigen could be a good substitute for ManLAM serology for the diagnosis of TB.
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Affiliation(s)
- Ayelet Barenholz
- Department of Clinical Microbiology, The Faculty of Medicine of the Hebrew University of Jerusalem, Jerusalem, Israel
| | - Avi-Hai Hovav
- Department of Clinical Microbiology, The Faculty of Medicine of the Hebrew University of Jerusalem, Jerusalem, Israel
| | - Yolanta Fishman
- Department of Clinical Microbiology, The Faculty of Medicine of the Hebrew University of Jerusalem, Jerusalem, Israel
| | - Galia Rahav
- Unit of Infectious Diseases, Sheba Medical Center, Ramat Gan, Israel
| | - Jonathan M Gershoni
- Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Hervé Bercovier
- Department of Clinical Microbiology, The Faculty of Medicine of the Hebrew University of Jerusalem, Jerusalem, Israel
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45
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Pramod SN, Venkatesh YP. Utility of pentose colorimetric assay for the purification of potato lectin, an arabinose-rich glycoprotein. Glycoconj J 2007; 23:481-8. [PMID: 17006640 DOI: 10.1007/s10719-006-6217-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2005] [Revised: 11/10/2005] [Accepted: 11/14/2005] [Indexed: 10/24/2022]
Abstract
Potato lectin (Solanum tuberosum agglutinin, STA) is an unusual glycoprotein containing approximately 50% carbohydrates by weight. Of the total carbohydrates, 92% is contributed by L: -arabinose, which are O-linked to hydroxyproline residues. The ferric chloride-orcinol assay (Bial's test), which is specific for pentoses has so far been used only for the determination of free pentoses in biological samples. However, this colorimetric assay has not been used for the detection of pentoses in bound form as it occurs in Solanaceae lectins (potato, tomato, and Datura lectins). Utilizing the pentose colorimetric assay for monitoring the presence of potato lectin, a simpler and shorter procedure for the purification of this lectin from potato tubers has been developed. The yield of potato lectin (1.73 mg per 100 g potato tuber) is twice compared to the yields reported in earlier procedures. Although potato lectin is well known for its specificity to free trimers and tetramers of N-acetyl-D: -glucosamine (GlcNAc), it possesses a similar specificity to the core (GlcNAc)(2) of N-linked glycoproteins. The utilization of the pentose assay in the purification of arabinose-rich lectins/agglutinins obviates the necessity for the use of agglutination assay in the various purification steps. The pentose assay appears to be a simple and convenient colorimetric assay for detecting any pentose-rich glycoprotein in plant extracts. The utility of the pentose assay appears to have a significant potential in the detection of hydroxyproline-rich glycoproteins (HRGPs), which are generally O-arabinosylated.
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Affiliation(s)
- Siddanakoppalu N Pramod
- Department of Biochemistry & Nutrition, Central Food Technological Research Institute (CFTRI), Mysore, 570 020, Karnataka State, India.
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Darwish OS, Callam CS, Hadad CM, Lowary TL. Regioselectivity in Alkylation Reactions of 1,2‐O‐Stannylene Acetals of d‐Arabinofuranose. J Carbohydr Chem 2007. [DOI: 10.1081/car-120026604] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Omar S. Darwish
- a Department of Chemistry , The Ohio State University , 100 West 18th Ave., Columbus, Ohio, 43210, USA
| | - Christopher S. Callam
- a Department of Chemistry , The Ohio State University , 100 West 18th Ave., Columbus, Ohio, 43210, USA
| | - Christopher M. Hadad
- a Department of Chemistry , The Ohio State University , 100 West 18th Ave., Columbus, Ohio, 43210, USA
| | - Todd L. Lowary
- a Department of Chemistry , The Ohio State University , 100 West 18th Ave., Columbus, Ohio, 43210, USA
- b Department of Chemistry and Alberta Ingenuity Centre for Carbohydrate Science , The University of Alberta , Gunning‐Lemieux Chemistry Centre, Edmonton, Alberta, T6G 2G2, Canada
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Matsuba T, Suzuki Y, Tanaka Y. Association of the Rv0679c protein with lipids and carbohydrates in Mycobacterium tuberculosis/Mycobacterium bovis BCG. Arch Microbiol 2007; 187:297-311. [PMID: 17252234 DOI: 10.1007/s00203-006-0195-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2006] [Accepted: 11/06/2006] [Indexed: 11/29/2022]
Abstract
The Rv0679c gene in Mycobacterium tuberculosis H37Rv encodes a protein with a predicted molecular mass of 16,586 Da consisting of 165 amino acids which contains a putative N-terminal signal sequence and a consensus lipoprotein-processing motif. Globomycin treatment, Triton X-114 separation and mass spectrometry analyses clarified a property of the Rv0679c protein as a lipoprotein. In addition, trifluoromethanesulphonic acid treatment of the lysate revealed an association of the recombinant Rv0679c protein with carbohydrates. The Rv0679c protein homolog of Mycobacterium bovis BCG was also expressed as the protein associated with lipids and carbohydrates. In Western blot analysis, each of the protein homolog and Lipoarabinomannan (LAM) was detected as a similar pattern by anti-Rv0679c and anti-LAM antibodies, respectively. Interestingly, the Rv0679c protein was detected in commercially available LAM purified from M. tuberculosis. Inhibition assay of LAM synthesis in M. bovis BCG by ethambutol showed an altered migration pattern of the Rv0679c protein to low molecular mass similar to that of LAM. The results suggest that the Rv0679c protein exists as a tight complex with LAM in M. tuberculosis/M. bovis BCG.
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Affiliation(s)
- Takashi Matsuba
- Division of Bacteriology, Department of Microbiology and Immunology, Faculty of Medicine, Tottori University, Yonago, Tottori 683-8503, Japan.
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Voisin S, Kus JV, Houliston S, St-Michael F, Watson D, Cvitkovitch DG, Kelly J, Brisson JR, Burrows LL. Glycosylation of Pseudomonas aeruginosa strain Pa5196 type IV pilins with mycobacterium-like alpha-1,5-linked d-Araf oligosaccharides. J Bacteriol 2006; 189:151-9. [PMID: 17085575 PMCID: PMC1797228 DOI: 10.1128/jb.01224-06] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pseudomonas aeruginosa is a gram-negative bacterium that uses polar type IV pili for adherence to various materials and for rapid colonization of surfaces via twitching motility. Within the P. aeruginosa species, five distinct alleles encoding variants of the structural subunit PilA varying in amino acid sequence, length, and presence of posttranslational modifications have been identified. In this work, a combination of mass spectrometry and nuclear magnetic resonance spectroscopy was used to identify a novel glycan modification on the pilins of the group IV strain Pa5196. Group IV pilins continued to be modified in a lipopolysaccharide (wbpM) mutant of Pa5196, showing that, unlike group I strains, the pilins of group IV are not modified with the O-antigen unit of the background strain. Instead, the pilin glycan was determined to be an unusual homo-oligomer of alpha-1,5-linked d-arabinofuranose (d-Araf). This sugar is uncommon in prokaryotes, occurring mainly in the cell wall arabinogalactan and lipoarabinomannan (LAM) polymers of mycobacteria, including Mycobacterium tuberculosis and Mycobacterium leprae. Antibodies raised against M. tuberculosis LAM specifically identified the glycosylated pilins from Pa5196, confirming that the glycan is antigenically, as well as chemically, identical to those of Mycobacterium. P. aeruginosa Pa5196, a rapidly growing strain of low virulence that expresses large amounts of glycosylated type IV pilins on its surface, represents a genetically tractable model system for elucidation of alternate pathways for biosynthesis of d-Araf and its polymerization into mycobacterium-like alpha-1,5-linked oligosaccharides.
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Affiliation(s)
- Sébastien Voisin
- Institute for Biological Sciences, National Research Council, Ottawa, Canada
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49
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Kaur D, Berg S, Dinadayala P, Gicquel B, Chatterjee D, McNeil MR, Vissa VD, Crick DC, Jackson M, Brennan PJ. Biosynthesis of mycobacterial lipoarabinomannan: role of a branching mannosyltransferase. Proc Natl Acad Sci U S A 2006; 103:13664-9. [PMID: 16945913 PMCID: PMC1557798 DOI: 10.1073/pnas.0603049103] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Lipoarabinomannan (LAM), one of the few known bacterial glycosylphosphoinositides (GPIs), occurs in various structural forms in Mycobacterium species. It has been implicated in key aspects of the physiology of Mycobacterium tuberculosis and the immunology and pathogenesis of tuberculosis. Yet, little is known of the biosynthesis of LAM. A bioinformatics approach identified putative integral membrane proteins, MSMEG4250 in Mycobacterium smegmatis and Rv2181 in M. tuberculosis, with 10 predicted transmembrane domains and a glycosyltransferase (GT) motif (DID), features that are common to eukaryotic mannosyltransferases (ManTs) of the GT-C superfamily that rely on polyprenyl-linked rather than nucleotide-linked sugar donors. Inactivation of M. smegmatis MSMEG4250 by allelic exchange resulted in altered growth and inability to synthesize lipomannan (LM) but accumulation of a previously uncharacterized, truncated LAM. MALDI-TOF/MS and NMR indicated a structure lower in molecular weight than the native molecule, a preponderance of 6-linked Manp residues, and the absence of 2,6-linked and terminal Manp. Complementation of the mutant with the corresponding ortholog of M. tuberculosis H37Rv restored normal LM/LAM synthesis. The data suggest that MSMEG4250 and Rv2181 are ManTs that are responsible for the addition of alpha(1-->2) branches to the mannan core of LM/LAM and that arrest of this branching in the mutant deters formation of native LAM. The results allow for the presentation of a unique model of LM and LAM biosynthesis. The generation of mutants defective in the synthesis of LM/LAM will help define the role of these GPIs in the immunology and pathogenesis of mycobacterial infections and physiology of the organism.
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Affiliation(s)
- Devinder Kaur
- *Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO 80523; and
| | - Stefan Berg
- *Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO 80523; and
| | - Premkumar Dinadayala
- *Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO 80523; and
| | - Brigitte Gicquel
- Unite de Genetique Mycobacterienne, Institut Pasteur, 25 Rue du Dr. Roux, 75724 Paris Cedex 15, France
| | - Delphi Chatterjee
- *Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO 80523; and
| | - Michael R. McNeil
- *Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO 80523; and
| | - Varalakshmi D. Vissa
- *Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO 80523; and
| | - Dean C. Crick
- *Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO 80523; and
| | - Mary Jackson
- Unite de Genetique Mycobacterienne, Institut Pasteur, 25 Rue du Dr. Roux, 75724 Paris Cedex 15, France
| | - Patrick J. Brennan
- *Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO 80523; and
- To whom correspondence should be addressed. E-mail:
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Gadikota RR, Callam CS, Appelmelk BJ, Lowary TL. Synthesis of Oligosaccharide Fragments of Mannosylated Lipoarabinomannan Appropriately Functionalized for Neoglycoconjugate Preparation. J Carbohydr Chem 2006. [DOI: 10.1081/car-120025322] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
| | - Christopher S. Callam
- a Department of Chemistry , Ohio State University , 100 West 18th Avenue, Columbus, Ohio, 43210, USA
| | - Ben J. Appelmelk
- b Department of Medical Microbiology , Vrije University, Medical School , Amsterdam, The Netherlands
| | - Todd L. Lowary
- a Department of Chemistry , Ohio State University , 100 West 18th Avenue, Columbus, Ohio, 43210, USA
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