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Dam TK, Hohman O, Sheppard L, Brewer CF, Bandyopadhyay P. Mechanism of multivalent glycoconjugate-lectin interaction: An update. Adv Carbohydr Chem Biochem 2023; 84:1-21. [PMID: 37979977 DOI: 10.1016/bs.accb.2023.10.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2023]
Abstract
Lectins are predominantly oligomeric proteins with several binding sites per molecule. Glycoconjugates are their natural ligands, which often possess multiple binding epitopes. Thus, lectin-glycoconjugate interactions are mostly multivalent in nature. The mechanism of multivalent binding is fundamentally different from those described for monovalent interactions in textbooks and research papers. Over the years, binding studies that make use of different lectins and a variety of multivalent glycoconjugate ligands were conducted in order to understand the underlying principles of multivalency. Starting with seemingly simple synthetic multivalent analogs, systematic studies were carried out using natural glycoconjugate ligands with increasing valency and complexity. Those ligands included multivalent glycoproteins, polyvalent polysaccharides, including glycosaminoglycans, as well as supra-valent mucins and proteoglycans. Models and mechanisms of multivalent binding derived from quantitative data are summarized in the present updated review.
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Affiliation(s)
- Tarun K Dam
- Laboratory of Mechanistic Glycobiology, Department of Chemistry, Michigan Technological University, Houghton, MI, United States; Health Research Institute, Michigan Technological University, Houghton, MI, United States.
| | - Olivia Hohman
- Laboratory of Mechanistic Glycobiology, Department of Chemistry, Michigan Technological University, Houghton, MI, United States
| | - Lucas Sheppard
- Laboratory of Mechanistic Glycobiology, Department of Chemistry, Michigan Technological University, Houghton, MI, United States
| | - C Fred Brewer
- Department of Molecular Pharmacology, Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Purnima Bandyopadhyay
- Laboratory of Mechanistic Glycobiology, Department of Chemistry, Michigan Technological University, Houghton, MI, United States
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2
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Ye X, Holland R, Wood M, Pasetka C, Palmer L, Samaridou E, McClintock K, Borisevich V, Geisbert TW, Cross RW, Heyes J. Combination treatment of mannose and GalNAc conjugated small interfering RNA protects against lethal Marburg virus infection. Mol Ther 2023; 31:269-281. [PMID: 36114672 PMCID: PMC9840110 DOI: 10.1016/j.ymthe.2022.09.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 08/28/2022] [Accepted: 09/12/2022] [Indexed: 02/02/2023] Open
Abstract
Marburg virus (MARV) infection results in severe viral hemorrhagic fever with mortalities up to 90%, and there is a pressing need for effective therapies. Here, we established a small interfering RNA (siRNA) conjugate platform that enabled successful subcutaneous delivery of siRNAs targeting the MARV nucleoprotein. We identified a hexavalent mannose ligand with high affinity to macrophages and dendritic cells, which are key cellular targets of MARV infection. This ligand enabled successful siRNA conjugate delivery to macrophages both in vitro and in vivo. The delivered hexa-mannose-siRNA conjugates rendered substantial target gene silencing in macrophages when supported by a mannose functionalized endosome release polymer. This hexa-mannose-siRNA conjugate was further evaluated alongside our hepatocyte-targeting GalNAc-siRNA conjugate, to expand targeting of infected liver cells. In MARV-Angola-infected guinea pigs, these platforms offered limited survival benefit when used as individual agents. However, in combination, they achieved up to 100% protection when dosed 24 h post infection. This novel approach, using two different ligands to simultaneously deliver siRNA to multiple cell types relevant to infection, provides a convenient subcutaneous route of administration for treating infection by these dangerous pathogens. The mannose conjugate platform has potential application to other diseases involving macrophages and dendritic cells.
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Affiliation(s)
- Xin Ye
- Genevant Sciences Corporation, Vancouver, BC V5T 4T5, Canada
| | - Richard Holland
- Genevant Sciences Corporation, Vancouver, BC V5T 4T5, Canada
| | - Mark Wood
- Genevant Sciences Corporation, Vancouver, BC V5T 4T5, Canada
| | - Chris Pasetka
- Genevant Sciences Corporation, Vancouver, BC V5T 4T5, Canada
| | - Lorne Palmer
- Genevant Sciences Corporation, Vancouver, BC V5T 4T5, Canada
| | - Eleni Samaridou
- Genevant Sciences Corporation, Vancouver, BC V5T 4T5, Canada
| | | | - Viktoriya Borisevich
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA; Galveston National Laboratory, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Thomas W Geisbert
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA; Galveston National Laboratory, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Robert W Cross
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA; Galveston National Laboratory, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - James Heyes
- Genevant Sciences Corporation, Vancouver, BC V5T 4T5, Canada.
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Study on Significance of Receptor Targeting in Killing of Intracellular Bacteria with Membrane‐Impermeable Antibiotics. ADVANCED THERAPEUTICS 2021. [DOI: 10.1002/adtp.202100168] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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4
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Danielson E, Dindo M, Porkovich AJ, Kumar P, Wang Z, Jain P, Mete T, Ziadi Z, Kikkeri R, Laurino P, Sowwan M. Non-enzymatic and highly sensitive lactose detection utilizing graphene field-effect transistors. Biosens Bioelectron 2020; 165:112419. [DOI: 10.1016/j.bios.2020.112419] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 06/26/2020] [Accepted: 06/29/2020] [Indexed: 12/19/2022]
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5
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Multivalency Beats Complexity: A Study on the Cell Uptake of Carbohydrate Functionalized Nanocarriers to Dendritic Cells. Cells 2020; 9:cells9092087. [PMID: 32932639 PMCID: PMC7564404 DOI: 10.3390/cells9092087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 09/01/2020] [Accepted: 09/09/2020] [Indexed: 11/17/2022] Open
Abstract
Herein, we report the synthesis of carbohydrate and glycodendron structures for dendritic cell targeting, which were subsequently bound to hydroxyethyl starch (HES) nanocapsules prepared by the inverse miniemulsion technique. The uptake of the carbohydrate-functionalized HES nanocapsules into immature human dendritic cells (hDCs) revealed a strong dependence on the used carbohydrate. A multivalent mannose-terminated dendron was found to be far superior in uptake compared to the structurally more complex oligosaccharides used.
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Pan L, Farouk MH, Qin G, Zhao Y, Bao N. The Influences of Soybean Agglutinin and Functional Oligosaccharides on the Intestinal Tract of Monogastric Animals. Int J Mol Sci 2018; 19:E554. [PMID: 29439523 PMCID: PMC5855776 DOI: 10.3390/ijms19020554] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 01/24/2018] [Accepted: 01/31/2018] [Indexed: 12/21/2022] Open
Abstract
Soybean agglutinin (SBA) is a non-fiber carbohydrate-related protein and the main anti-nutritional factor that exists in soybean or soybean products. SBA possesses a specific binding affinity for N-glyphthalide-d-galactosamine or galactose and has a covalently linked oligosaccharide chain. SBA mediates negative effects on animal intestinal health by influencing the intestinal structure, barrier function, mucosal immune system, and the balance of the intestinal flora. Functional oligosaccharides are non-digestible dietary oligosaccharides that are commonly applied as prebiotics since the biological effects of the functional oligosaccharides are to increase the host health by improving mucosal structure and function, protecting the integrity of the intestinal structure, modulating immunity, and balancing the gastrointestinal microbiota. The purpose of this review is to describe the structure and anti-nutritional functions of SBA, summarize the influence of SBA and functional oligosaccharides on the intestinal tract of monogastric animals, and emphasize the relationship between SBA and oligosaccharides. This review provides perspectives on applying functional oligosaccharides for alleviating the anti-nutritional effects of SBA on the intestinal tract.
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Affiliation(s)
- Li Pan
- Key Laboratory of Animal Production, Product Quality and Security, Ministry of Education, Key Laboratory of Animal Nutrition and Feed Science, Jilin Province, College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China.
| | - Mohammed Hamdy Farouk
- Key Laboratory of Animal Production, Product Quality and Security, Ministry of Education, Key Laboratory of Animal Nutrition and Feed Science, Jilin Province, College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China.
- Animal Production Department, Faculty of Agriculture, Al-Azhar University, Nasr City, Cairo 11884, Egypt.
| | - Guixin Qin
- Key Laboratory of Animal Production, Product Quality and Security, Ministry of Education, Key Laboratory of Animal Nutrition and Feed Science, Jilin Province, College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China.
| | - Yuan Zhao
- Key Laboratory of Animal Production, Product Quality and Security, Ministry of Education, Key Laboratory of Animal Nutrition and Feed Science, Jilin Province, College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China.
| | - Nan Bao
- Key Laboratory of Animal Production, Product Quality and Security, Ministry of Education, Key Laboratory of Animal Nutrition and Feed Science, Jilin Province, College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China.
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Cai Z, Sasmal A, Liu X, Asher SA. Responsive Photonic Crystal Carbohydrate Hydrogel Sensor Materials for Selective and Sensitive Lectin Protein Detection. ACS Sens 2017; 2:1474-1481. [PMID: 28934853 DOI: 10.1021/acssensors.7b00426] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Lectin proteins, such as the highly toxic lectin protein, ricin, and the immunochemically important lectin, jacalin, play significant roles in many biological functions. It is highly desirable to develop a simple but efficient method to selectively detect lectin proteins. Here we report the development of carbohydrate containing responsive hydrogel sensing materials for the selective detection of lectin proteins. The copolymerization of a vinyl linked carbohydrate monomer with acrylamide and acrylic acid forms a carbohydrate hydrogel that shows specific "multivalent" binding to lectin proteins. The resulting carbohydrate hydrogels are attached to 2-D photonic crystals (PCs) that brightly diffract visible light. This diffraction provides an optical readout that sensitively monitors the hydrogel volume. We utilize lactose, galactose, and mannose containing hydrogels to fabricate a series of 2-D PC sensors that show strong selective binding to the lectin proteins ricin, jacalin, and concanavalin A (Con A). This binding causes a carbohydrate hydrogel shrinkage which significantly shifts the diffraction wavelength. The resulting 2-D PC sensors can selectively detect the lectin proteins ricin, jacalin, and Con A. These unoptimized 2-D PC hydrogel sensors show a limit of detection (LoD) of 7.5 × 10-8 M for ricin, a LoD of 2.3 × 10-7 M for jacalin, and a LoD of 3.8 × 10-8 M for Con A, respectively. This sensor fabrication approach may enable numerous sensors for the selective detection of numerous lectin proteins.
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Affiliation(s)
- Zhongyu Cai
- Department
of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Aniruddha Sasmal
- Department
of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Xinyu Liu
- Department
of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Sanford A. Asher
- Department
of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
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A glucose/mannose binding lectin from litchi ( Litchi chinensis) seeds: Biochemical and biophysical characterizations. Biochem Biophys Rep 2016; 6:242-252. [PMID: 29214228 PMCID: PMC5689159 DOI: 10.1016/j.bbrep.2016.05.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 04/27/2016] [Accepted: 05/02/2016] [Indexed: 02/01/2023] Open
Abstract
Background Lectins are highly important biomolecules to study several biological processes. A novel α-D-glucose/mannose specific lectin was isolated from the seeds of litchi fruits (Litchi chinensis) and its various biophysical and biochemical properties were studied. Methods Purification was done by successive Sephadex G 100 and Con A-Sepharose 4B affinity chromatography. SDS-PAGE, Surface Plasmon Resonance (SPR), steady state absorbance, fluorescence, time-correlated single-photon counting, circular dichroism and antibiofilm activity by measuring total protein estimation and azocasein degradation assay have been performed. Results The purified lectin is a homodimer of molecular mass ~ 54 kDa. The amount of lectin required for hemagglutination of normal human O erythrocytes was 6.72 µg/ml. Among the saccharides tested, Man-α-(1,6)-Man was found to be the most potent inhibitor (0.01 mM) determined by hemagglutination inhibition assay. Steady state and time resolved fluorescence measurements revealed that litchi lectin formed ground state complex with maltose (Ka=4.9 (±0.2)×104 M-1), which indicated static quenching (Stern-Volmer (SV) constant Ksv=4.6 (±0.2)×104 M-1). CD measurements demonstrated that litchi lectin showed no overall conformational change during the binding process with maltose. The lectin showed antibiofilm activity against Pseudomonus aeruginosa. Conclusions A novel homodimeric lectin has been purified from the seeds of litchi fruits (Litchi chinensis) having specificity for α-d-glucose/mannose. The thermodynamics and conformational aspects of its interaction with maltose have been studied in detail. The antibiofilm activity of this lectin towards Pseudomonus aeruginosa has been explored. General significance The newly identified litchi lectin is highly specific for α-d-glucose/mannose with an important antibiofilm activity towards Pseudomonus aeruginosa.
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Abhinav KV, Samuel E, Vijayan M. Archeal lectins: An identification through a genomic search. Proteins 2015; 84:21-30. [DOI: 10.1002/prot.24949] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 10/13/2015] [Accepted: 10/19/2015] [Indexed: 11/09/2022]
Affiliation(s)
- K. V. Abhinav
- Molecular Biophysics Unit, Indian Institute of Science; Bangalore 560 012 India
| | - Ebenezer Samuel
- Molecular Biophysics Unit, Indian Institute of Science; Bangalore 560 012 India
| | - M. Vijayan
- Molecular Biophysics Unit, Indian Institute of Science; Bangalore 560 012 India
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10
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Hecht ES, McCord JP, Muddiman DC. Definitive Screening Design Optimization of Mass Spectrometry Parameters for Sensitive Comparison of Filter and Solid Phase Extraction Purified, INLIGHT Plasma N-Glycans. Anal Chem 2015; 87:7305-12. [PMID: 26086806 PMCID: PMC4664066 DOI: 10.1021/acs.analchem.5b01609] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
High-throughput, quantitative processing of N-linked glycans would facilitate large-scale studies correlating the glycome with disease and open the field to basic and applied researchers. We sought to meet these goals by coupling filter-aided-N-glycan separation (FANGS) to the individuality normalization when labeling with glycan hydrazide tags (INLIGHT) for analysis of plasma. A quantitative comparison of this method was conducted against solid phase extraction (SPE), a ubiquitous and trusted method for glycan purification. We demonstrate that FANGS-INLIGHT purification was not significantly different from SPE in terms of glycan abundances, variability, functional classes, or molecular weight distributions. Furthermore, to increase the depth of glycome coverage, we executed a definitive screening design of experiments (DOE) to optimize the MS parameters for glycan analyses. We optimized MS parameters across five N-glycan responses using a standard glycan mixture, translated these to plasma and achieved up to a 3-fold increase in ion abundances.
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Affiliation(s)
| | | | - David C. Muddiman
- North Carolina State University, Department of Chemistry, Raleigh, NC
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11
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Zhang JT, Cai Z, Kwak DH, Liu X, Asher SA. Two-dimensional photonic crystal sensors for visual detection of lectin concanavalin A. Anal Chem 2014; 86:9036-41. [PMID: 25162117 DOI: 10.1021/ac5015854] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We fabricated a two-dimensional (2-D) photonic crystal lectin sensing material that utilizes light diffraction from a 2-D colloidal array attached to the surface of a hydrogel that contains mannose carbohydrate groups. Lectin-carbohydrate interactions create hydrogel cross-links that shrink the hydrogel volume and decrease the 2-D particle spacing. This mannose containing 2-D photonic crystal sensor detects Concanavalin A (Con A) through shifts in the 2-D diffraction wavelength. Con A concentrations can be determined by measuring the diffracted wavelength or visually determined from the change in the sensor diffraction color. The concentrations are easily monitored by measuring the 2-D array Debye ring diameter. Our observed detection limit for Con A is 0.02 mg/mL (0.7 μM). The 2-D photonic crystal sensors are completely reversible and can monitor Con A solution concentration changes.
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Affiliation(s)
- Jian-Tao Zhang
- Department of Chemistry, University of Pittsburgh , 219 Parkman Avenue, Pittsburgh, Pennsylvania 15260, United States
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12
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Zhang S, Moussodia RO, Sun HJ, Leowanawat P, Muncan A, Nusbaum CD, Chelling KM, Heiney PA, Klein ML, André S, Roy R, Gabius HJ, Percec V. Mimicking Biological Membranes with Programmable Glycan Ligands Self-Assembled from Amphiphilic Janus Glycodendrimers. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201403186] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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13
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Zhang S, Moussodia RO, Sun HJ, Leowanawat P, Muncan A, Nusbaum CD, Chelling KM, Heiney PA, Klein ML, André S, Roy R, Gabius HJ, Percec V. Mimicking biological membranes with programmable glycan ligands self-assembled from amphiphilic Janus glycodendrimers. Angew Chem Int Ed Engl 2014; 53:10899-903. [PMID: 24923471 DOI: 10.1002/anie.201403186] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 05/02/2014] [Indexed: 12/16/2022]
Abstract
An accelerated modular synthesis produced 18 amphiphilic Janus glycodendrimers with three different topologies formed from either two or one carbohydrate head groups or a mixed constellation with a noncarbohydrate hydrophilic arm. By simple injection of their THF solutions into water or buffer, all of the Janus compounds self-assembled into uniform, stable, and soft unilamellar vesicles, denoted glycodendrimersomes. The mixed constellation topology glycodendrimersomes were demonstrated to be most efficient in binding plant, bacterial, and human lectins. This evidence with biomedically relevant receptors offers a promising perspective for the application of such glycodendrimersomes in targeted drug delivery, vaccines, and other areas of nanomedicine.
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Affiliation(s)
- Shaodong Zhang
- Roy & Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104-6323 (USA) http://percec02.chem.upenn.edu/
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14
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Brogioni B, Berti F. Surface plasmon resonance for the characterization of bacterial polysaccharide antigens: a review. MEDCHEMCOMM 2014. [DOI: 10.1039/c4md00088a] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
This review gives an overview of significant applications of flow SPR to investigate the specific interactions of bacterial polysaccharide antigens.
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15
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Hartmann M, Betz P, Sun Y, Gorb SN, Lindhorst TK, Krueger A. Saccharide-Modified Nanodiamond Conjugates for the Efficient Detection and Removal of Pathogenic Bacteria. Chemistry 2012; 18:6485-92. [DOI: 10.1002/chem.201104069] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Indexed: 11/11/2022]
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Arif SM, Vijayan M. Structural diversity based on variability in quaternary association. A case study involving eubacterial and related SSBs. Methods Mol Biol 2012; 922:23-35. [PMID: 22976175 DOI: 10.1007/978-1-62703-032-8_2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Eubacterial and related single-stranded DNA-binding proteins (SSBs) exhibit considerable variability in their quaternary association in spite of their having the same tertiary fold. The variability involves differences in the orientation of dimers in the tetrameric molecule (or of two-domain subunits in the dimeric molecule) and that of monomers in each dimer. The presence of an additional strand in mycobacterial and related SSBs, which clamps the dimers together, is a major determinant of the mode of quaternary association in them. The variability in quaternary structure has implications to the stability of the protein and possibly to its mode of DNA binding.
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Affiliation(s)
- S M Arif
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India
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Safina G. Application of surface plasmon resonance for the detection of carbohydrates, glycoconjugates, and measurement of the carbohydrate-specific interactions: A comparison with conventional analytical techniques. A critical review. Anal Chim Acta 2012; 712:9-29. [DOI: 10.1016/j.aca.2011.11.016] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Revised: 10/07/2011] [Accepted: 11/04/2011] [Indexed: 12/16/2022]
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18
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Sharma A, Vijayan M. Quaternary association in β-prism I fold plant lectins: Insights from X-ray crystallography, modelling and molecular dynamics. J Biosci 2011; 36:793-808. [DOI: 10.1007/s12038-011-9166-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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19
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Euzen R, Reymond JL. Glycopeptide dendrimers: tuning carbohydrate–lectin interactions with amino acids. ACTA ACUST UNITED AC 2011; 7:411-21. [DOI: 10.1039/c0mb00177e] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Paul A, Antony M, Mathai J, Appukuttan PS. High polymeric IgA content facilitates recognition of microbial polysaccharide-natural serum antibody immune complexes by immobilized human galectin-1. Immunol Lett 2010; 136:55-60. [PMID: 21147166 DOI: 10.1016/j.imlet.2010.12.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2010] [Revised: 11/27/2010] [Accepted: 12/06/2010] [Indexed: 11/30/2022]
Abstract
Dextran-binding immunoglobulin (DIg) and anti-β-glucan antibody (ABG) are naturally occurring human serum antibodies specific to α- and β-glucoside epitopes respectively of polysaccharide antigens and heavily enriched in IgA. ABG and DIg are shown here to have much more of their IgA in polymeric form than does serum IgA in general. Cell wall β-glucans and glycoproteins of the widely consumed yeast (Saccharomyces cerevisiae) offered several hundred fold better ligands for ABG than did small β-glucosides. Candida albicans cell wall antigen (CCA), a commonly encountered polysaccharide-rich fungal antigen was recognized by normal human serum anti-carbohydrate antibodies to precipitate maximally at a definite stoichiometry typical of immune complexes (IC). IC formed in serum in vitro on addition of CCA contained a significantly higher percentage of IgA than did either naturally occurring IC or serum. Polymeric IgA was far better ligand than monomeric IgA for both anti-IgA antibody and the most widely expressed human tissue lectin galectin-1 which recognizes O-linked oligosaccharides characteristic of IgA, in contrast to N-linked oligosaccharides present in all immunoglobulins. Moreover, desialylation by neuraminidase, an enzyme released into circulation during many microbial infections and diabetes, increased lectin-binding activity of polymeric IgA much more than that of monomeric IgA. Human galectin-1 immobilized in active form in vitro sugar-specifically captured IgA and IgA-containing IC formed by CCA in serum but not IgG. Results suggest that while high IgA content especially in polymeric form may render polysaccharide IC more susceptible to tissue uptake, desialylation of IgA in IC could enhance the process.
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Affiliation(s)
- Anu Paul
- Department of Biochemistry, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, Kerala 695 011, India
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Lee A, Nakano M, Hincapie M, Kolarich D, Baker MS, Hancock WS, Packer NH. The lectin riddle: glycoproteins fractionated from complex mixtures have similar glycomic profiles. OMICS-A JOURNAL OF INTEGRATIVE BIOLOGY 2010; 14:487-99. [PMID: 20726804 DOI: 10.1089/omi.2010.0075] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
One common method used for analyzing the glycoproteome is chromatography using multiple lectins that display different affinities toward oligosaccharide structures. Much has been done to determine lectin affinity using standard glycoproteins with known glycosylation; however, a knowledge of the selectivity and specificity of lectins exposed to complex mixtures of proteins is required if they are to be used as a means of studying the glycoproteome. In the present study, three lectins (Concanavalin A, Jacalin, and Wheat Germ Agglutinin) were used to fractionate glycoproteins from two different complex environments: (1) cell membranes and (2) plasma. Reproducible enrichment of glycoproteins from these samples has been shown to result from the combined use of these lectins. However, the global glycan profiles of the released N- and O-linked oligosaccharides from the glycoproteins retained by the lectins, and from those glycoproteins that did not bind, using both these complex samples, were found to be very similar. That is, although the lectins selectively and reproducibly retained some glycoproteins, other proteins with the same attached oligosaccharide structures did not bind. Some small N- and O-glycan differences were observed in the bound fractions but there was little absolute specificity toward individual oligosaccharide structures known to have high affinity to these lectins. These data indicate that lectins are useful for fractionating glycoproteins from complex mixtures, but that the overall glycoproteome is not isolated by this approach.
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Affiliation(s)
- Albert Lee
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Australia
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22
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Hayes ML, Eytan RI, Hellberg ME. High amino acid diversity and positive selection at a putative coral immunity gene (tachylectin-2). BMC Evol Biol 2010; 10:150. [PMID: 20482872 PMCID: PMC2880987 DOI: 10.1186/1471-2148-10-150] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2009] [Accepted: 05/19/2010] [Indexed: 12/22/2022] Open
Abstract
Background Genes involved in immune functions, including pathogen recognition and the activation of innate defense pathways, are among the most genetically variable known, and the proteins that they encode are often characterized by high rates of amino acid substitutions, a hallmark of positive selection. The high levels of variation characteristic of immunity genes make them useful tools for conservation genetics. To date, highly variable immunity genes have yet to be found in corals, keystone organisms of the world's most diverse marine ecosystem, the coral reef. Here, we examine variation in and selection on a putative innate immunity gene from Oculina, a coral genus previously used as a model for studies of coral disease and bleaching. Results In a survey of 244 Oculina alleles, we find high nonsynonymous variation and a signature of positive selection, consistent with a putative role in immunity. Using computational protein structure prediction, we generate a structural model of the Oculina protein that closely matches the known structure of tachylectin-2 from the Japanese horseshoe crab (Tachypleus tridentatus), a protein with demonstrated function in microbial recognition and agglutination. We also demonstrate that at least three other genera of anthozoan cnidarians (Acropora, Montastrea and Nematostella) possess proteins structurally similar to tachylectin-2. Conclusions Taken together, the evidence of high amino acid diversity, positive selection and structural correspondence to the horseshoe crab tachylectin-2 suggests that this protein is 1) part of Oculina's innate immunity repertoire, and 2) evolving adaptively, possibly under selective pressure from coral-associated microorganisms. Tachylectin-2 may serve as a candidate locus to screen coral populations for their capacity to respond adaptively to future environmental change.
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Affiliation(s)
- Marshall L Hayes
- Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, NY 14853, USA
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23
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The role of metal ions in substrate recognition and stability of concanavalin A: a molecular dynamics study. Biophys J 2010; 96:21-34. [PMID: 18849415 DOI: 10.1529/biophysj.108.134601] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2008] [Accepted: 09/12/2008] [Indexed: 11/18/2022] Open
Abstract
The binding of carbohydrate substrates to concanavalin A (Canavalia ensiformis agglutinin (ConA)) is essential for its interaction with various glycoproteins. Even though metal ions are known to control the sugar binding ability of legume lectins, the interplay between sugar and metal ion binding to ConA has not been elucidated in a detailed manner at the atomic level. We have carried out long, explicit solvent molecular dynamics simulations for tetrameric, dimeric, and monomeric forms of ConA in both the presence and absence of trimannoside and metal ions. Detailed analyses of these trajectories for various oligomeric forms under different environmental conditions have revealed dynamic conformational changes associated with the demetalization of ConA. We found that demetalization of ConA leads to large conformational changes in the ion binding loop, with some of the loop residues moving as far as 17 A with respect to their positions in the native trimannoside and metal ion-bound crystal structure. However, the ?-sheet core of the protein remains relatively unperturbed. In addition, the high mobility of the ion binding loop results in drifting of the substrates in the absence of bound metal ions. These simulations provide a theoretical rationale for previous experimental observations regarding the abolition of the sugar binding ability upon demetalization. We also found that the amino acid stretches of ConA, having high B-factor values in the crystal structure, show relatively greater mobility in the simulations. The overall agreement of the results of our simulations with various experimental studies suggests that the force field parameters and length of simulations used in our study are adequate to mimic the dynamic structural changes in the ConA protein.
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Conformational behavior of α-d-mannopyranosyl-(1→6)-α,β-d-mannose complexed with two mannose-binding plant lectins, Allium sativam agglutinin I and concanavalin A, using NMR and molecular modeling techniques. Carbohydr Res 2010; 345:61-7. [DOI: 10.1016/j.carres.2009.09.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2009] [Revised: 09/16/2009] [Accepted: 09/21/2009] [Indexed: 11/21/2022]
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25
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Lehrer RI, Jung G, Ruchala P, Andre S, Gabius HJ, Lu W. Multivalent binding of carbohydrates by the human alpha-defensin, HD5. THE JOURNAL OF IMMUNOLOGY 2009; 183:480-90. [PMID: 19542459 DOI: 10.4049/jimmunol.0900244] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Four of the six human alpha-defensins (human neutrophil peptides 1-3 and human alpha-defensin 5; HD5) have a lectin-like ability to bind glycosylated proteins. Using HD5 as a model, we applied surface plasmon resonance techniques to gain insights into this property. HD5 bound natural glycoproteins > neoglycoproteins based on BSA > nonglycosylated BSA >> free sugars. The affinity of HD5 for simple sugars covalently bound to BSA was orders of magnitude greater than its affinity for the same sugars in solution. The affinity of HD5 for protein-bound carbohydrates resulted from multivalent interactions which may also involve noncarbohydrate residues of the proteins. HD5 showed concentration-dependent self-association that began at submicromolar concentrations and proceeded to dimer and tetramer formation at concentrations below 5 microM. The (R9A, R28A) and (R13A, R32A) analogs of HD5 showed greatly reduced self-association as well as minimal binding to BSA and to BSA-affixed sugars. From this and other evidence, we conclude that the extensive binding of HD5 to (neo)glycoproteins results from multivalent nonspecific interactions of individual HD5 molecules with carbohydrate and noncarbohydrate moieties of the target molecule and that the primary binding events are magnified and enhanced by subsequent in situ assembly and oligomerization of HD5. Self-association and multivalent binding may play integral roles in the ability of HD5 to protect against infections caused by viruses and other infectious agents.
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Affiliation(s)
- Robert I Lehrer
- David Geffen School of Medicine at University of California at Los Angeles, 90095, USA.
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26
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Misawa Y, Masaka R, Yano M, Murata T, Usui T. Synthesis of Spacer-linked Divalent Glycosides by Chitinolytic Enzyme from <i>Amycolatopsis orientalis</i>. J Appl Glycosci (1999) 2009. [DOI: 10.5458/jag.56.89] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Affiliation(s)
| | - Ryuichi Masaka
- Department of Applied Biological Chemistry, Faculty of Agriculture, Shizuoka University
| | - Megumi Yano
- Department of Applied Biological Chemistry, Faculty of Agriculture, Shizuoka University
| | - Takeomi Murata
- Department of Applied Biological Chemistry, Faculty of Agriculture, Shizuoka University
| | - Taichi Usui
- Department of Applied Biological Chemistry, Faculty of Agriculture, Shizuoka University
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27
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Kinetic Analysis of Glycoprotein–Lectin Interactions by Label-Free Internal Reflection Ellipsometry. Clin Proteomics 2008. [DOI: 10.1007/s12014-008-9007-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Abstract
Introduction
Glycoproteomics is undergoing rapid development, largely as a result of advances in technologies for isolating glycoproteins and analyzing glycan structures. However, given the number and diversity of glycans, there is need for new technologies that can more rapidly provide differential carbohydrate–protein structural information on a large scale. We describe a new microarray platform based on a label-free imaging ellipsometry technique, which permits simultaneous detection of multiple glycoprotein–lectin interactions without the need for reporter labels, while still providing high throughput kinetic information at much lower cost. Our results demonstrate the utility of LFIRE™ (Label-Free Internal Reflection Ellipsometry) for the rapid kinetic screening of carbohydrate–lectin recognition. The technology was also used to evaluate the benefits of the lectin immobilization format using multi-lectin affinity chromatography (M-LAC) to capture glycoproteins (with enhanced binding strength or avidity) from biological samples. Using a printed panel of lectins, singly or in combination, we examined the binding characteristics of standard glycoproteins.
Results and Discussion
Using kinetic measurements, it was observed that the binding strength of lectins to carbohydrates is enhanced using a multi-lectin strategy, suggesting that improved selectivity and specificity can lead to increased functional avidity. The data presented confirm that this label-free technology can be used to effectively screen single or combinations of lectins. Furthermore, the combination of LFIRE™ and M-LAC may permit more rapid and sensitive identification of novel biomarkers based on carbohydrate changes in glycoproteins, and lead to a better understanding of the connections of glycan function in cellular mechanisms of health and disease.
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Insights into the structural basis of the pH-dependent dimer-tetramer equilibrium through crystallographic analysis of recombinant Diocleinae lectins. Biochem J 2008; 409:417-28. [PMID: 17937659 DOI: 10.1042/bj20070942] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The structural ground underlying the pH-dependency of the dimer-tetramer transition of Diocleinae lectins was investigated by equilibrium sedimentation and X-ray crystal structure determination of wild-type and site-directed mutants of recombinant lectins. Synthetic genes coding for the full-length alpha-chains of the seed lectins of Dioclea guianensis (termed r-alphaDguia) and Dioclea grandiflora (termed r-alphaDGL) were designed and expressed in Escherichia coli. This pioneering approach, which will be described in detail in the present paper, yielded recombinant lectins displaying carbohydrate-binding activity, dimer-tetramer equilibria and crystal structures indistinguishable from their natural homologues. Conversion of the pH-stable tetrameric r-alphaDGL into a structure exhibiting pH-dependent dimer-tetramer transition was accomplished through mutations that abolished the interdimeric interactions at the central cavity of the tetrameric lectins. Both the central and the peripheral interacting regions bear structural information for formation of the canonical legume lectin tetramer. We hypothesize that the strength of the ionic contacts at these sites may be modulated by the pH, leading to dissociation of those lectin structures that are not locked into a pH-stable tetramer through interdimeric contacts networking the central cavity loops.
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29
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Brimble MA, Kowalczyk R, Harris PWR, Dunbar PR, Muir VJ. Synthesis of fluorescein-labelled O-mannosylated peptides as components for synthetic vaccines: comparison of two synthetic strategies. Org Biomol Chem 2007; 6:112-21. [PMID: 18075655 DOI: 10.1039/b712926b] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Mannose-binding proteins on the surface of antigen-presenting cells (APCs) are capable of recognizing and internalizing foreign agents in the early stages of immune response. These receptors offer a potential target for synthetic vaccines, especially vaccines designed to stimulate T cells. We set out to synthesize a series of fluorescein-labelled O-mannosylated peptides using manual solid phase peptide synthesis (SPPS) on pre-loaded Wang resin, in order to test their ability to bind mannose receptors on human APCs in vitro. A flexible and reliable method for the synthesis of fluorescein-labelled O-mannosylated glycopeptides was desired in order to study their lectin-binding properties using flow cell cytometry. Two synthetic strategies were investigated: incorporation of a fluorescein label into the peptide chain via a lysine side chain epsilon-amino group at the final stage of standard Fmoc solid phase peptide synthesis or attachment of the fluorescein label to the N(alpha)-amino group of a lysine with further incorporation of a mannosylated peptide unit through the side chain N(epsilon)-amino group. The latter strategy proved more effective in that it facilitated SPPS by positioning the growing mannosylated peptide chain further removed from the fluorescein label.
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Affiliation(s)
- Margaret A Brimble
- Department of Chemistry, University of Auckland, 23 Symonds St, Auckland 1142, New Zealand.
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30
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Natchiar SK, Suguna K, Surolia A, Vijayan M. Peanut agglutinin, a lectin with an unusual quaternary structure and interesting ligand binding properties. CRYSTALLOGR REV 2007. [DOI: 10.1080/08893110701382087] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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31
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Pillai B, Cherney MM, Hiraga K, Takada K, Oda K, James MNG. Crystal structure of scytalidoglutamic peptidase with its first potent inhibitor provides insights into substrate specificity and catalysis. J Mol Biol 2006; 365:343-61. [PMID: 17069854 DOI: 10.1016/j.jmb.2006.09.058] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2006] [Revised: 09/20/2006] [Accepted: 09/22/2006] [Indexed: 11/21/2022]
Abstract
Scytalidoglutamic peptidase (SGP) from Scytalidium lignicolum is the founding member of the newly discovered\ family of peptidases, G1, so far found exclusively in fungi. The crystal structure of SGP revealed a previously undescribed fold for peptidases and a unique catalytic dyad of residues Gln53 and Glu136. Surprisingly, the beta-sandwich structure of SGP is strikingly similar to members of the carbohydrate-binding concanavalin A-like lectins/glucanases superfamily. By analogy with the active sites of aspartic peptidases, a mechanism employing nucleophillic attack by a water molecule activated by the general base functionality of Glu136 has been proposed. Here, we report the first crystal structures of SGP in complex with two transition state peptide analogs designed to mimic the tetrahedral intermediate of the proteolytic reaction. Of these two analogs, the one containing a central S-hydroxyl group is a potent sub-nanomolar inhibitor of SGP. The inhibitor binds non-covalently to the concave surface of the upper beta-sheet and enables delineation of the S4 to S3' substrate specificity pockets of the enzyme. Structural differences in these pockets account for the unique substrate preferences of SGP among peptidases having an acidic pH optimum. Inhibitor binding is accompanied by a structuring of the region comprising residues Tyr71-Gly80 from being mostly disordered in the apoenzyme and leading to positioning of crucial active site residues for establishing enzyme-inhibitor contacts. In addition, conformational rearrangements are seen in a disulfide bridged surface loop (Cys141-Cys148), which moves inwards, partially closing the open substrate binding cleft of the native enzyme. The non-hydrolysable scissile bond analog of the inhibitor is located in the active site forming close contacts with Gln53 and Glu136. The nucleophilic water molecule is displaced and a unique mode of binding is observed with the S-OH of the inhibitor occupying the oxyanion binding site of the proposed tetrahedral intermediate. Details of the enzyme-inhibitor interactions and mechanistic interpretations are discussed.
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Affiliation(s)
- B Pillai
- Group in Protein Structure and Function, Department of Biochemistry, University of Alberta, Edmonton, Alberta, T6G 2H7, Canada
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32
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Del Sol FG, Cavada BS, Calvete JJ. Crystal structures of Cratylia floribunda seed lectin at acidic and basic pHs. Insights into the structural basis of the pH-dependent dimer-tetramer transition. J Struct Biol 2006; 158:1-9. [PMID: 17251039 DOI: 10.1016/j.jsb.2006.08.014] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2006] [Revised: 08/17/2006] [Accepted: 08/25/2006] [Indexed: 11/26/2022]
Abstract
Structural determinants underlaying the pH-dependent dimer-tetramer transition of Diocleinae lectins were investigated from the structures of Cratylia floribunda seed lectin crystallized in conditions where it exist as a dimer (pH 4.6) or as a tetramer (pH 8.5). The acidic (aCFL) and the basic (bCFL) tetramers superimpose with overall r.m.s.d. of 0.53 A, though interdimer contacts are drastically reduced in aCFL, and the r.m.s.d. for the superposition of the 117-120 loops of aCFL vs. the bCFL tetramer is 1.29 A. Our data support the view that His51 plays a role in determining the conformation of the central cavity loops and that interdimer contacts involving ordered loop residues stabilize the canonical, pH-dependent tetramer. In the bCFL tetramer, hydrogen bonds between Asn118 and Thr120 of monomers A and D and residues Ser66, Ser108, Ser110, and Thr49 of the opposite monomer stabilize the canonical, pH-dependent tetrameric lectin structure. In CFL, Asn131 makes intradimer contacts with Asn122 and Ala123. In comparison, His131 in Dioclea grandiflora lectin establishes a network of interdimer interactions bridging the four central loops of the pH-independent tetramer. Our data provide new insights into the participation of specific amino acid residues in the mechanism of the quaternary association of Diocleinae lectins.
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Bandaru NM, Sampath S, Jayaraman N. Synthesis and Langmuir studies of bivalent and monovalent alpha-D-mannopyranosides with lectin Con A. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:9591-6. [PMID: 16207040 DOI: 10.1021/la051433o] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Highly avid interaction between carbohydrate ligands and lectin receptors nominally requires the ligand presentation in a clustered form. We present herein an approach involving Langmuir monolayer formation of the sugar ligands and the assessment of their lectin binding at the air-water interface. Bivalent alpha-D-mannopyranoside containing the glycolipid ligand was used to study its binding profiles with lectin Con A, in comparison to the corresponding monovalent glycolipid. In addition to the bivalent and monovalent nature of the glycolipid ligands at the molecular level, the ligand densities at the monolayer level were varied with the aid of a nonsugar lipid molecule so as to obtain mixed monolayers with various sugar-nonsugar ratios. Lectin binding of bivalent and monovalent ligands at different ratios was monitored by differential changes in the surface area per molecule of the mixed monolayer, with and without the lectin. The present study shows that maximal binding of the lectin to the bivalent ligand occurs at lower sugar densities at the interface ( approximately 10% sugar in the mixed monolayer) than for that of the monovalent ligand ( approximately 20% sugar in the mixed monolayer). It is observed that complete coverage of the monolayer with only the sugar ligands does not allow all of the sugars to be functionally active.
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Affiliation(s)
- Narasimha Murthy Bandaru
- Department of Organic Chemistry and Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560 012, India
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34
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Gallego del Sol F, Nagano C, Cavada BS, Calvete JJ. The first crystal structure of a Mimosoideae lectin reveals a novel quaternary arrangement of a widespread domain. J Mol Biol 2005; 353:574-83. [PMID: 16185708 DOI: 10.1016/j.jmb.2005.08.055] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2005] [Revised: 08/22/2005] [Accepted: 08/23/2005] [Indexed: 11/16/2022]
Abstract
The crystal structures of the apo and mannose-bound Parkia platycephala seed lectin represent the first structure of a Mimosoideae lectin and a novel circular arrangement of beta-prism domains, and highlight the adaptability of the beta-prism fold as a building block in the evolution of plant lectins. The P.platycephala lectin is a dimer both in solution and in the crystals. Mannose binding to each of the three homologous carbohydrate-recognition domains of the lectin occurs through different modes, and restrains the flexibility of surface-exposed loops and residues involved in carbohydrate recognition. The planar array of carbohydrate-binding sites on the rim of the toroid-shaped structure of the P.platycephala lectin dimer immediately suggests a mechanism to promote multivalent interactions leading to cross-linking of carbohydrate ligands as part of the host strategy against phytopredators and pathogens. The cyclic structure of the P.platycephala lectin points to the convergent evolution of a structural principle for the construction of lectins involved in host defense or in attacking other organisms.
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35
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Srinivas O, Mitra N, Surolia A, Jayaraman N. Photoswitchable cluster glycosides as tools to probe carbohydrate-protein interactions: synthesis and lectin-binding studies of azobenzene containing multivalent sugar ligands. Glycobiology 2005; 15:861-73. [PMID: 15872151 DOI: 10.1093/glycob/cwi069] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Synthetic cluster glycosides have often been used to unravel mechanisms of carbohydrate-protein interactions. Although synthetic cluster glycosides are constituted on scaffolds to achieve high avidities in lectin binding, there have been no known attempts to modulate the orientations of the sugar clusters with the aid of a functional scaffold onto which the sugar units are linked. Herein, we describe synthesis, physical, and lectin-binding studies of a series of alpha-D-mannopyranoside and beta-D-galactopyranosyl-(1-->4)-beta-D-glucopyranoside glycoclusters that are attached to a photoswitchable azobenzenoid core. These glycoclusters were synthesized by the amidation of amine-tethered glycopyranosides with azobenzene carbonyl chlorides. From kinetic studies, the cis forms of the azobenzene-glycopyranoside derivative were found to be more stable in aqueous solutions than in organic solvents. Molecular modeling studies were performed to estimate the relative geometries of the photoswitchable glycoclusters in the trans- and cis-isomeric forms. Isothermal titration calorimetry (ITC) was employed to assess the binding of these glycoclusters to lectins peanut agglutinin (PNA) and concanavalin A (Con A). Although binding affinities were enhanced several orders higher as the valency of the sugar was increased, a biphasic-binding profile in ITC plots was observed during few glycoclusters lectin-binding processes. The biphasic-binding profile indicates a "cooperativity" in the binding process. An important outcome of this study is that in addition to inherent clustering of the sugar units as a molecular feature, an induced clustering emanates because of the isomerization of the trans form of the azobenzene scaffold to the cis-isomeric form.
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Affiliation(s)
- Oruganti Srinivas
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, Karnataka, India
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36
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Botos I, Wlodawer A. Proteins that bind high-mannose sugars of the HIV envelope. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2005; 88:233-82. [PMID: 15572157 DOI: 10.1016/j.pbiomolbio.2004.05.001] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
A broad range of proteins bind high-mannose carbohydrates found on the surface of the envelope protein gp120 of the human immunodeficiency virus and thus interfere with the viral life cycle, providing a potential new way of controlling HIV infection. These proteins interact with the carbohydrate moieties in different ways. A group of them interacts as typical C-type lectins via a Ca2+ ion. Another group interacts with specific single, terminal sugars, without the help of a metal cation. A third group is involved in more intimate interactions, with multiple carbohydrate rings and no metal ion. Finally, there is a group of lectins for which the interaction mode has not yet been elucidated. This review summarizes, principally from a structural point of view, the current state of knowledge about these high-mannose binding proteins and their mode of sugar binding.
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Affiliation(s)
- Istvan Botos
- Macromolecular Crystallography Laboratory, National Cancer Institute, NCI-Frederick, Building 536, Room 5, Frederick, MD 21702-1201, USA
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37
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Gardiner JM. The therapeutic potential of synthetic multivalent carbohydrates. Expert Opin Investig Drugs 2005; 7:405-11. [PMID: 15991981 DOI: 10.1517/13543784.7.3.405] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Recent progress has been made in constructing synthetic multivalent carbohydrate ligands targeted at known or probable multivalent carbohydrate ligand receptors. Multivalency can dramatically compensate for the weak affinities of individual carbohydrate ligand moieties. Multivalent branched ligand mimetics have been described bearing multiple mannoside, galactoside, lactoside and Sialyl Lewis X (SLe(x)) moieties. New methods for polymeric backbone construction have provided glyco-polymers of defined and controllable size. Promising examples of multivalent ligands giving significant increases in binding potency are being pursued. These types of agents have extensive therapeutic potential in treating infectious diseases or host abnormalities, and also offer exciting potential as drug-conjugate cell-targeting agents.
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Affiliation(s)
- J M Gardiner
- University of Manchester Institute of Science & Technology, UK
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38
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Liu W, Yang N, Ding J, Huang RH, Hu Z, Wang DC. Structural mechanism governing the quaternary organization of monocot mannose-binding lectin revealed by the novel monomeric structure of an orchid lectin. J Biol Chem 2005; 280:14865-76. [PMID: 15649901 DOI: 10.1074/jbc.m411634200] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Two isoforms of an antifungal protein, gastrodianin, were isolated from two subspecies of the orchid Gastrodia elata, belonging to the protein superfamily of monocot mannose-specific lectins. In the context that all available structures in this superfamily are oligomers so far, the crystal structures of the orchid lectins, both at 2.0 A, revealed a novel monomeric structure. It resulted from the rearrangement of the C-terminal peptide inclusive of the 12th beta-strand, which changes from the "C-terminal exchange" into a "C-terminal self-assembly" mode. Thus, the overall tertiary scaffold is stabilized with an intramolecular beta-sheet instead of the hybrid observed on subunit/subunit interface in all known homologous dimeric or tetrameric lectins. In contrast to the constrained extended conformation with a cis peptide bond between residues 98 and 99 commonly occurring in oligomers, a beta-hairpin forms from position 97 to 101 with a normal trans peptide bond at the corresponding site in gastrodianin, which determines the topology of the C-terminal peptide and thereby its unique fold pattern. Sequence and structure comparison shows that residue replacement and insertion at the position where the beta-hairpin occurs in association with cis-trans inter-conversion of the specific peptide bond (97-98) are possibly responsible for such a radical structure switch between monomers and oligomers. Moreover, this seems to be a common melody controlling the quaternary states among bulb lectins through studies on sequence alignment. The observations revealed a structural mechanism by which the quaternary organization of monocot mannose binding lectins could be governed. The mutation experiment performed on maltose-binding protein-gastrodianin fusion protein followed by a few biochemical detections provides direct evidence to support this conclusion. Potential carbohydrate recognition sites and biological implications of the orchid lectin based on its monomeric state are also discussed in this paper.
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Affiliation(s)
- Wei Liu
- Center for Structural and Molecular Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
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Suseelan KN, Mitra R, Pandey R, Sainis KB, Krishna TG. Purification and characterization of a lectin from wild sunflower (Helianthus tuberosus L.) tubers. Arch Biochem Biophys 2002; 407:241-7. [PMID: 12413497 DOI: 10.1016/s0003-9861(02)00517-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A lectin (HTTL) was isolated from Helianthus tuberosus L. (wild sunflower) tubers using ion-exchange chromatography, gel filtration, and affinity chromatography. The lectin agglutinated both untreated and trypsin-treated rabbit erythrocytes and did not agglutinate human blood cells of groups A, B, and O. The gel filtration showed the native molecular mass of 72 kDa and subunit molecular masses of 17 and 18.5 kDa on 12% SDS-PAGE. The lectin activity was inhibited by D-mannose. The tetrameric protein revealed a unique characteristic by forming a broad zone of protein in native PAGE at pH 8.3, which dissociated into seven subunits of varying e/m ratios on acid gel at pH 4.3. These seven bands revealed two polypeptide species of molecular masses 17 and 18.5 kDa on 12% SDS-PAGE, as in the case of the native protein. The result indicated that of the seven subunits, three were homotetramers of 17 kDa, one was a homotetramer of 18.5 kDa, and three were heterotetramers of 17 and 18.5 kDa. The lectin was thermostable with broad pH optima (pH 4-8) and had no requirement for divalent metal cations for its activity. The amino acid composition showed that the lectin contained higher amounts of glycine, alanine, and lysine, but no methionine. The sugar content was estimated to be 5.3% mannose equivalent. The HTTL was mitogenic to mouse spleen (total) cells at 25 microg/ml concentration. The lectin showed characteristics different from those of the earlier reported H. tuberosus tuber lectins and hence opens up a new avenue to investigate the structure-function relationship of lectin in Helianthus species.
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Affiliation(s)
- K N Suseelan
- Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Mumbai, India
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40
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Ramos MV, Cavada BS, Mazard AM, Rougé P. Interaction of Diocleinae lectins with glycoproteins based in surface plasmon resonance. Mem Inst Oswaldo Cruz 2002; 97:275-9. [PMID: 12016458 DOI: 10.1590/s0074-02762002000200025] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Interaction of glucose/mannose-binding lectins in solution with immobilized glycoproteins was followed in real time using surface plasmon resonance technology. The lectins which share many biochemical and structural features could be clearly differentiated in terms of their specificity for complex glycoconjugates. The most prominent interaction of the lectins with PHA-E comparing with soybean agglutinin, both glycoproteins exhibiting high mannose oligosaccharides, suggests that the whole structure of the glycoproteins themselves, may interfere in affinity. These findings also support the hypothesis that minor amino acid replacements in the primary sequence of the lectins might be responsible for their divergence in fine specificity and biological activities. This is the first report using surface plasmon resonance technology that evidences differences of Diocleinae lectins in respect their fine glycan-specificity.
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Affiliation(s)
- Marcio V Ramos
- Departamento de Biologia, Universidade Federal do Ceará, Fortaleza, CE, 60451-970, Brasil
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41
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Dam TK, Brewer CF. Thermodynamic studies of lectin-carbohydrate interactions by isothermal titration calorimetry. Chem Rev 2002; 102:387-429. [PMID: 11841248 DOI: 10.1021/cr000401x] [Citation(s) in RCA: 381] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tarun K Dam
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, USA
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42
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Thoma G, Duthaler RO, Magnani JL, Patton JT. Nanomolar E-selectin inhibitors: 700-fold potentiation of affinity by multivalent ligand presentation. J Am Chem Soc 2001; 123:10113-4. [PMID: 11592897 DOI: 10.1021/ja0164430] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- G Thoma
- Novartis Pharma, AG CH-4002 Basel, Switzerland
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43
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Barre A, Bourne Y, Van Damme EJ, Peumans WJ, Rougé P. Mannose-binding plant lectins: different structural scaffolds for a common sugar-recognition process. Biochimie 2001; 83:645-51. [PMID: 11522393 DOI: 10.1016/s0300-9084(01)01315-3] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Mannose-specific lectins are widely distributed in higher plants and are believed to play a role in recognition of high-mannose type glycans of foreign micro-organisms or plant predators. Structural studies have demonstrated that the mannose-binding specificity of lectins is mediated by distinct structural scaffolds. The mannose/glucose-specific legume (e.g., Con A, pea lectin) exhibit the canonical twelve-stranded beta-sandwich structure. In contrast to legume lectins that interact with both mannose and glucose, the monocot mannose-binding lectins (e.g., the Galanthus nivalis agglutinin or GNA from bulbs) react exclusively with mannose and mannose-containing N-glycans. These lectins possess a beta-prism structure. More recently, an increasing number of mannose-specific lectins structurally related to jacalin (e.g., the lectins from the Jerusalem artichoke, banana or rice), which also exhibit a beta-prism organization, were characterized. Jacalin itself was re-defined as a polyspecific lectin which, in addition to galactose, also interacts with mannose and mannose-containing glycans. Finally the B-chain of the type II RIP of iris, which has the same beta-prism structure as all other members of the ricin-B family, interacts specifically with mannose and galactose. This structural diversity associated with the specific recognition of high-mannose type glycans highlights the importance of mannose-specific lectins as recognition molecules in higher plants.
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Affiliation(s)
- A Barre
- Institut de Pharmacologie et de Biologie Structurale, UMR-CNRS 5089, 205, route de Narbonne, 31077 Toulouse cedex 4, France
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44
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Abstract
The three-dimensional structures of LG/LNS domains from neurexin, the laminin alpha 2 chain and sex hormone-binding globulin reveal a close structural relationship to the carbohydrate-binding pentraxins and other lectins. However, these LG/LNS domains appear to have a preferential ligand-interaction site distinct from the carbohydrate-binding sites found in lectins, and this interaction site accommodates not only sugars but also steroids and proteins. In fact, the LG/LNS domain interaction site has features reminiscent of the antigen-combining sites in immunoglobulins. The LG/LNS domain presents an interesting case in which the fold has remained conserved but the functional sites have evolved; consequently, making predictions of structure-function relationships on the basis of the lectin fold alone is difficult.
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Affiliation(s)
- G Rudenko
- Howard Hughes Medical Institute and Dept of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390-9050, USA.
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45
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Jeong S, Eom T, Kim S, Lee S, Yu J. In vitro selection of the RNA aptamer against the Sialyl Lewis X and its inhibition of the cell adhesion. Biochem Biophys Res Commun 2001; 281:237-43. [PMID: 11178986 DOI: 10.1006/bbrc.2001.4327] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Sialyl Lewis X (sLeX) is a tetra-saccharide glycoconjugate of membrane proteins. It acts as a ligand for the selectin proteins during cell adhesion of inflammatory process. Aberrant overexpression of sLeX is also a characteristic of various cancer cells, especially for highly malignant ones. In this paper, the sLeX-specific RNA aptamer was selected using a random RNA library and its affinity and specificity were measured by Surface Plasmon Resonance technique. Affinity of the selected RNA was increased about 1000-fold as compared with the original RNA pool. RNA aptamer bound more specifically to its cognate sugar than to any other similar sugars. Inhibition of the cell adhesion was also shown by in vitro static assay of sLeX-expressing HL60 cells to the E- and P-selectins. It suggests that the high affinity carbohydrate specific RNA aptamer could be used as an alternative to the antibody.
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Affiliation(s)
- S Jeong
- Department of Molecular Biology, Dankook University, Seoul, 140-714, Korea.
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46
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Peumans WJ, Van Damme EJ, Barre A, Rougé P. Classification of plant lectins in families of structurally and evolutionary related proteins. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2001; 491:27-54. [PMID: 14533788 DOI: 10.1007/978-1-4615-1267-7_3] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
The majority of plant lectins can be classified in seven families of structurally and evolutionary related proteins. Within a given lectin family most but not necessarily all members are built up of protomers with a similar primary structure and overall 3-D fold. The overall structure of the native lectins is not only determined by the structure of the protomers but depends also on the degree of oligomerization and in some cases on the post-translational processing of the lectin precursors. In general, lectin families are fairly homogeneous for what concerns the overall specificity of the individual lectins, which illustrates that the 3-D structure of the binding site has been conserved during evolution. In the case of the jacalin-related lectins the occurrence of a mannose- and galactose-binding subfamily can be explained by the fact that a post-translational cleavage of the protomers (of the galactose-binding subfamily) yields a slightly altered binding site. Unlike the other families, the legume lectins display a wide range of specificites, which is clearly reflected in the occurrence of sugar-binding sites with a different 3-D structure.
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Affiliation(s)
- W J Peumans
- Laboratory for Phytopathology and Plant Protection, Katholieke Universiteit Leuven, Willem de Croylaan 42, 3001 Leuven, Belgium
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47
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Dam TK, Roy R, Das SK, Oscarson S, Brewer CF. Binding of multivalent carbohydrates to concanavalin A and Dioclea grandiflora lectin. Thermodynamic analysis of the "multivalency effect". J Biol Chem 2000; 275:14223-30. [PMID: 10799500 DOI: 10.1074/jbc.275.19.14223] [Citation(s) in RCA: 165] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Binding of a series of synthetic multivalent carbohydrate analogs to the Man/Glc-specific lectins concanavalin A and Dioclea grandiflora lectin was investigated by isothermal titration microcalorimetry. Dimeric analogs possessing terminal alpha-D-mannopyranoside residues, and di-, tri-, and tetrameric analogs possessing terminal 3, 6-di-O-(alpha-D-mannopyranosyl)-alpha-D-mannopyranoside residues, which is the core trimannoside of asparagine-linked carbohydrates, were selected in order to compare the effects of low and high affinity analogs, respectively. Experimental conditions were found that prevented precipitation of the carbohydrate-lectin cross-linked complexes during the isothermal titration microcalorimetry experiments. The results show that the value of n, the number of binding sites on each monomer of the lectins, is inversely proportional to the number of binding epitopes (valency) of each carbohydrate. Hence, n values close to 1.0, 0.50, and 0.25 were observed for the binding of mono-, di-, and tetravalent sugars, respectively, to the two lectins. Importantly, differences in the functional valency of a triantennary analog for concanavalin A and D. grandiflora lectin are observed. The enthalpy of binding, DeltaH, is observed to be directly proportional to the number of binding epitopes in the higher affinity analogs. For example, DeltaH of a tetravalent trimannoside analog is nearly four times greater than that of the corresponding monovalent analog. Increases in K(a) values of the multivalent carbohydrates relative to monovalent analogs, known as the "multivalency effect," are shown to be due to more positive entropy (TDeltaS) contributions to binding of the former sugars. A general thermodynamic model for distinguishing binding of multivalent ligands to a single receptor with multiple, equal subsites versus binding to separate receptor molecules is given.
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Affiliation(s)
- T K Dam
- Department of Molecular Pharmacology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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49
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Taroni C, Jones S, Thornton JM. Analysis and prediction of carbohydrate binding sites. PROTEIN ENGINEERING 2000; 13:89-98. [PMID: 10708647 DOI: 10.1093/protein/13.2.89] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
An analysis of the characteristic properties of sugar binding sites was performed on a set of 19 sugar binding proteins. For each site six parameters were evaluated: solvation potential, residue propensity, hydrophobicity, planarity, protrusion and relative accessible surface area. Three of the parameters were found to distinguish the observed sugar binding sites from the other surface patches. These parameters were then used to calculate the probability for a surface patch to be a carbohydrate binding site. The prediction was optimized on a set of 19 non-homologous carbohydrate binding structures and a test prediction was carried out on a set of 40 protein-carbohydrate complexes. The overall accuracy of prediction achieved was 65%. Results were in general better for carbohydrate-binding enzymes than for the lectins, with a rate of success of 87%.
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Affiliation(s)
- C Taroni
- Biomolecular Structure and Modelling Unit, Department of Biochemistry and Molecular Biology, University College London, Gower Street, London, WC1E 6BT, UK
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50
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Dimick SM, Powell SC, McMahon SA, Moothoo DN, Naismith JH, Toone EJ. On the Meaning of Affinity: Cluster Glycoside Effects and Concanavalin A. J Am Chem Soc 1999. [DOI: 10.1021/ja991729e] [Citation(s) in RCA: 199] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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