1
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Li R, Li Y, Bai Y, Yi P, Sun C, Shi S, Gong YK. Achieving superior anticoagulation of endothelial membrane mimetic coating by heparin grafting at zwitterionic biocompatible interfaces. Int J Biol Macromol 2024; 257:128574. [PMID: 38052281 DOI: 10.1016/j.ijbiomac.2023.128574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Revised: 11/16/2023] [Accepted: 11/30/2023] [Indexed: 12/07/2023]
Abstract
Thrombosis and bleeding are common complications of blood-contacting medical device therapies. In this work, an endothelium membrane mimetic coating (PMPCC/Hep) has been created to address these challenges. The coating is fabricated by multi-point anchoring of a phosphorylcholine copolymer (poly-MPC-co-MSA, PMPCC) with carboxylic side chains and end-group grafting of unfractionated heparin (Hep) onto polydopamine precoated blood-contacting material surfaces. The PMPCC coating forms an ultrathin cell outer membrane mimetic layer to resist protein adsorption and platelet adhesion. The tiny defects/pores of the PMPCC layer provide entrances for heparin end-group to be inserted and grafted onto the sub-layer amino groups. The combination of the PMPCC cell membrane mimetic anti-fouling nature with the grafted heparin bioactivity further enhances the anticoagulation performance of the formed endothelium membrane mimetic PMPCC/Hep coating. Compared to conventional Hep coating, the PMPCC/Hep coating further decreases protein adsorption and platelet adhesion by 50 % and 90 %, respectively. More significantly, the PMPCC/Hep coating shows a superior anticoagulation activity, even significantly higher than that of an end-point-attached heparin coating. Furthermore, the blood coagulation function is well preserved in the PMPCC/Hep coating anticoagulation strategy. All the results support that the PMPCC/Hep coating strategy has great potential in developing more efficient and safer blood-contacting medical devices.
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Affiliation(s)
- Rong Li
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xian 710127, Shaanxi, PR China
| | - Yin Li
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xian 710127, Shaanxi, PR China
| | - Yunjie Bai
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xian 710127, Shaanxi, PR China
| | - Panpan Yi
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xian 710127, Shaanxi, PR China
| | - Chenwei Sun
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xian 710127, Shaanxi, PR China
| | - Suqing Shi
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xian 710127, Shaanxi, PR China; Institute of Materials Science and New Technology, Northwest University, Xian 710127, Shaanxi, China
| | - Yong-Kuan Gong
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xian 710127, Shaanxi, PR China; Institute of Materials Science and New Technology, Northwest University, Xian 710127, Shaanxi, China.
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2
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Liang A, Desai U. Advances in Studying Glycosaminoglycan-Protein Interactions Using Capillary Electrophoresis. Methods Mol Biol 2022; 2303:365-387. [PMID: 34626394 DOI: 10.1007/978-1-0716-1398-6_30] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Methods for studying interactions between glycosaminoglycans (GAGs) and proteins have assumed considerable significance as their biological importance increases. Capillary electrophoresis (CE) is a powerful method to study these interactions due to its speed, high efficiency, and low sample/reagent consumption. In addition, CE works effectively under a wide range of physiologically relevant conditions. This chapter presents the state of the art on CE methods for studying GAG-protein interactions including affinity capillary electrophoresis (ACE), capillary zone electrophoresis (CZE), frontal analysis (FA)/frontal analysis continuous capillary electrophoresis (FACCE), and capillary electrokinetic chromatography (CEC) with detailed experimental protocols for ACE and CZE methods.
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Affiliation(s)
- Aiye Liang
- Department of Chemistry, Charleston Southern University, North Charleston, SC, USA.
| | - Umesh Desai
- Department of Medicinal Chemistry and Institute for Structural Biology and Drug Discovery, Virginia Commonwealth University, Richmond, VA, USA
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3
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Nahain AA, Ignjatovic V, Monagle P, Tsanaktsidis J, Vamvounis G, Ferro V. Sulfonated RAFT Copolymers as Heparin Mimetics: Synthesis, Reactivity Ratios, and Anticoagulant Activity. Macromol Biosci 2020; 20:e2000110. [PMID: 32627962 DOI: 10.1002/mabi.202000110] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 06/16/2020] [Indexed: 12/17/2022]
Abstract
The glycosaminoglycan heparin is a clinically important anticoagulant drug, primarily used to reduce the risk of blood clots (thrombosis) during surgery. Despite its importance in medicine and its continuous use over many decades, heparin suffers from several limitations associated with its heterogeneity and its extraction from animal tissues. In order to address these limitations, reversible addition-fragmentation chain transfer polymerization is utilized to prepare a library of heparin mimetic copolymers from the sulfonated monomers sodium 4-styrene sulfonate, potassium-3-sulfopropyl acrylate, potassium-3-sulfopropyl methacrylate, and sodium-2-acrylamido-2-methyl-1-propane sulfonate. Copolymers are prepared using combinations of two different monomers in various ratios. Monomer reactivity ratios are also determined for some representative monomer combinations, and all polymers are characterized by 1 H NMR spectroscopy and gel permeation chromatography. The anticoagulant activities of the copolymers are determined by activated partial thromboplastin time and thrombin clotting time assays and structure-activity relationships are explored.
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Affiliation(s)
- Abdullah Al Nahain
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, 4072, Australia.,Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, 4072, Australia
| | - Vera Ignjatovic
- Haematology Research, Murdoch Children's Research Institute, Parkville, Victoria, 3052, Australia.,Department of Paediatrics, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Paul Monagle
- Haematology Research, Murdoch Children's Research Institute, Parkville, Victoria, 3052, Australia.,Department of Paediatrics, The University of Melbourne, Parkville, Victoria, 3010, Australia.,Department of Clinical Haematology, Royal Children's Hospital, Parkville, Victoria, 3052, Australia
| | - John Tsanaktsidis
- CSIRO Manufacturing, Research Way, Clayton, Victoria, 3168, Australia
| | - George Vamvounis
- College of Science and Engineering, James Cook University, Townsville, Queensland, 4811, Australia
| | - Vito Ferro
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, 4072, Australia.,Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, Queensland, 4072, Australia
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4
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Niu C, Zhao Y, Bobst CE, Savinov SN, Kaltashov IA. Identification of Protein Recognition Elements within Heparin Chains Using Enzymatic Foot-Printing in Solution and Online SEC/MS. Anal Chem 2020; 92:7565-7573. [PMID: 32347711 DOI: 10.1021/acs.analchem.0c00115] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Understanding molecular mechanisms governing interactions of glycosaminoglycans (such as heparin) with proteins remains challenging due to their enormous structural heterogeneity. Commonly accepted approaches seek to reduce the structural complexity by searching for "binding epitopes" within the limited subsets of short heparin oligomers produced either enzymatically or synthetically. A top-down approach presented in this work seeks to preserve the chemical diversity displayed by heparin by allowing the longer and structurally diverse chains to interact with the client protein. Enzymatic lysis of the protein-bound heparin chains followed by the product analysis using size exclusion chromatography with online mass spectrometry detection (SEC/MS) reveals the oligomers that are protected from lysis due to their tight association with the protein, and enables their characterization (both the oligomer length, and the number of incorporated sulfate and acetyl groups). When applied to a paradigmatic heparin/antithrombin system, the new method generates a series of oligomers with surprisingly distinct sulfation levels. The extent of sulfation of the minimal-length binder (hexamer) is relatively modest yet persistent, consistent with the notion of six sulfate groups being both essential and sufficient for antithrombin binding. However, the masses of longer surviving chains indicate complete sulfation of disaccharides beyond the hexasaccharide core. Molecular dynamics simulations confirm the existence of favorable electrostatic interactions between the high charge-density saccharide residues flanking the "canonical" antithrombin-binding hexasaccharide and the positive patch on the surface of the overall negatively charged protein. Furthermore, electrostatics may rescue the heparin/protein interaction in the absence of the canonical binding element.
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Affiliation(s)
- Chendi Niu
- Chemistry Department, University of Massachusetts-Amherst, 240 Thatcher Way, Amherst, Massachusetts 01003, United States
| | - Yunlong Zhao
- Chemistry Department, University of Massachusetts-Amherst, 240 Thatcher Way, Amherst, Massachusetts 01003, United States
| | - Cedric E Bobst
- Chemistry Department, University of Massachusetts-Amherst, 240 Thatcher Way, Amherst, Massachusetts 01003, United States
| | - Sergey N Savinov
- Biochemistry and Molecular Biology Department, University of Massachusetts-Amherst, 240 Thatcher Way, Amherst, Massachusetts 01003, United States
| | - Igor A Kaltashov
- Chemistry Department, University of Massachusetts-Amherst, 240 Thatcher Way, Amherst, Massachusetts 01003, United States
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5
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Minsky BB, Dubin PL, Kaltashov IA. Electrostatic Forces as Dominant Interactions Between Proteins and Polyanions: an ESI MS Study of Fibroblast Growth Factor Binding to Heparin Oligomers. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2017; 28:758-767. [PMID: 28211013 PMCID: PMC5808462 DOI: 10.1007/s13361-017-1596-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Revised: 12/26/2016] [Accepted: 01/04/2017] [Indexed: 05/24/2023]
Abstract
The interactions between fibroblast growth factors (FGFs) and their receptors (FGFRs) are facilitated by heparan sulfate (HS) and heparin (Hp), highly sulfated biological polyelectrolytes. The molecular basis of FGF interactions with these polyelectrolytes is highly complex due to the structural heterogeneity of HS/Hp, and many details still remain elusive, especially the significance of charge density and minimal chain length of HS/Hp in growth factor recognition and multimerization. In this work, we use electrospray ionization mass spectrometry (ESI MS) to investigate the association of relatively homogeneous oligoheparins (octamer, dp8, and decamer, dp10) with acidic fibroblast growth factor (FGF-1). This growth factor forms 1:1, 2:1, and 3:1 protein/heparinoid complexes with both dp8 and dp10, and the fraction of bound protein is highly dependent on protein/heparinoid molar ratio. Multimeric complexes are preferentially formed on the highly sulfated Hp oligomers. Although a variety of oligomers appear to be binding-competent, there is a strong correlation between the affinity and the overall level of sulfation (the highest charge density polyanions binding FGF most strongly via multivalent interactions). These results show that the interactions between FGF-1 and Hp oligomers are primarily directed by electrostatics, and also demonstrate the power of ESI MS as a tool to study multiple binding equilibria between proteins and structurally heterogeneous polyanions. Graphical Abstract ᅟ.
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Affiliation(s)
- Burcu Baykal Minsky
- Department of Chemistry, University of Massachusetts-Amherst, Amherst, MA, 01003, USA
| | - Paul L Dubin
- Department of Chemistry, University of Massachusetts-Amherst, Amherst, MA, 01003, USA
| | - Igor A Kaltashov
- Department of Chemistry, University of Massachusetts-Amherst, Amherst, MA, 01003, USA.
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6
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Xu Y, Liu M, Faisal M, Si Y, Guo Y. Selective protein complexation and coacervation by polyelectrolytes. Adv Colloid Interface Sci 2017; 239:158-167. [PMID: 27378068 DOI: 10.1016/j.cis.2016.06.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 06/03/2016] [Indexed: 12/17/2022]
Abstract
This review discusses the possible relationship between protein charge anisotropy, protein binding affinity, polymer structure, and selective phase separation. We hope that a fundamental understanding of primarily electrostatically driven protein-polyelectrolyte (PE) interactions can enable the prediction of selective protein binding, and hence selective coacervation through non-specific electrostatics. Such research will partially challenge the assumption that specific binding has to be realized through specific binding sites with a variety of short-range interactions and some geometric match. More specifically, the recent studies on selective binding of proteins by polyelectrolytes were examined from different assemblies in addition to the electrostatic features of proteins and PEs. At the end, the optimization of phase separation based on binding affinity for selective coacervation and some considerations relevant to using PEs for protein purification were also overviewed.
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Affiliation(s)
- Yisheng Xu
- State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China; Engineering Research Center of Materials Chemical Engineering of Xinjiang Bintuan, Shihezi University, Xinjiang 832000, China.
| | - Miaomiao Liu
- State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Mostufa Faisal
- State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Yi Si
- Department of Cardiovascular Surgery, Xinhua Hospital Affiliated of Shanghai Jiaotong University School of Medicine, Shanghai 200092, China
| | - Yanchuan Guo
- Technical Institute of Physics and Chemistry, Chinese Academy of Science, Beijing 100190,China.
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7
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Liu Y, Winter HH, Perry SL. Linear viscoelasticity of complex coacervates. Adv Colloid Interface Sci 2017; 239:46-60. [PMID: 27633928 DOI: 10.1016/j.cis.2016.08.010] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 08/31/2016] [Accepted: 08/31/2016] [Indexed: 01/15/2023]
Abstract
Rheology is a powerful method for material characterization that can provide detailed information about the self-assembly, structure, and intermolecular interactions present in a material. Here, we review the use of linear viscoelastic measurements for the rheological characterization of complex coacervate-based materials. Complex coacervation is an electrostatically and entropically-driven associative liquid-liquid phase separation phenomenon that can result in the formation of bulk liquid phases, or the self-assembly of hierarchical, microphase separated materials. We discuss the need to link thermodynamic studies of coacervation phase behavior with characterization of material dynamics, and provide parallel examples of how parameters such as charge stoichiometry, ionic strength, and polymer chain length impact self-assembly and material dynamics. We conclude by highlighting key areas of need in the field, and specifically call for the development of a mechanistic understanding of how molecular-level interactions in complex coacervate-based materials affect both self-assembly and material dynamics.
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Affiliation(s)
- Yalin Liu
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - H Henning Winter
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, MA 01003, USA
| | - Sarah L Perry
- Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, MA 01003, USA.
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8
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Meneghetti MCZ, Hughes AJ, Rudd TR, Nader HB, Powell AK, Yates EA, Lima MA. Heparan sulfate and heparin interactions with proteins. J R Soc Interface 2016; 12:0589. [PMID: 26289657 DOI: 10.1098/rsif.2015.0589] [Citation(s) in RCA: 196] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Heparan sulfate (HS) polysaccharides are ubiquitous components of the cell surface and extracellular matrix of all multicellular animals, whereas heparin is present within mast cells and can be viewed as a more sulfated, tissue-specific, HS variant. HS and heparin regulate biological processes through interactions with a large repertoire of proteins. Owing to these interactions and diverse effects observed during in vitro, ex vivo and in vivo experiments, manifold biological/pharmacological activities have been attributed to them. The properties that have been thought to bestow protein binding and biological activity upon HS and heparin vary from high levels of sequence specificity to a dependence on charge. In contrast to these opposing opinions, we will argue that the evidence supports both a level of redundancy and a degree of selectivity in the structure-activity relationship. The relationship between this apparent redundancy, the multi-dentate nature of heparin and HS polysaccharide chains, their involvement in protein networks and the multiple binding sites on proteins, each possessing different properties, will also be considered. Finally, the role of cations in modulating HS/heparin activity will be reviewed and some of the implications for structure-activity relationships and regulation will be discussed.
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Affiliation(s)
- Maria C Z Meneghetti
- Departamento de Bioquímica, Universidade Federal de São Paulo (UNIFESP), Rua Três de Maio, São Paulo 40440-020, Brazil
| | - Ashley J Hughes
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg 40530, Sweden Department of Biochemistry, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Timothy R Rudd
- The National Institute for Biological Standards and Control (NIBSC), South Mimms, Potters Bar, Hertfordshire EN6 3QC, UK Department of Biochemistry, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Helena B Nader
- Departamento de Bioquímica, Universidade Federal de São Paulo (UNIFESP), Rua Três de Maio, São Paulo 40440-020, Brazil
| | - Andrew K Powell
- School of Pharmacy and Biomolecular Science, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF, UK Department of Biochemistry, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Edwin A Yates
- Department of Biochemistry, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK Departamento de Bioquímica, Universidade Federal de São Paulo (UNIFESP), Rua Três de Maio, São Paulo 40440-020, Brazil
| | - Marcelo A Lima
- Departamento de Bioquímica, Universidade Federal de São Paulo (UNIFESP), Rua Três de Maio, São Paulo 40440-020, Brazil Department of Biochemistry, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
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9
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Xu J, Lei Z, Guo J, Huang J, Wang W, Reibetanz U, Xu S. Trapping and Driving Individual Charged Micro-particles in Fluid with an Electrostatic Device. NANO-MICRO LETTERS 2016; 8:270-281. [PMID: 30460287 PMCID: PMC6223688 DOI: 10.1007/s40820-016-0087-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 02/05/2016] [Indexed: 05/04/2023]
Abstract
A variety of micro-tweezers techniques, such as optical tweezers, magnetic tweezers, and dielectrophoresis technique, have been applied intensively in precise characterization of micro/nanoparticles and bio-molecules. They have contributed remarkably in better understanding of working mechanisms of individual sub-cell organelles, proteins, and DNA. In this paper, we present a controllable electrostatic device embedded in a microchannel, which is capable of driving, trapping, and releasing charged micro-particles suspended in microfluid, demonstrating the basic concepts of electrostatic tweezers. Such a device is scalable to smaller size and offers an alternative to currently used micro-tweezers for application in sorting, selecting, manipulating, and analyzing individual micro/nanoparticles. Furthermore, the system offers the potential in being combined with dielectrophoresis and other techniques to create hybrid micro-manipulation systems.
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Affiliation(s)
- Jingjing Xu
- Key Laboratory for the Physics & Chemistry of Nanodevices, and Department of Electronics, Peking University, Beijing, 100871 People’s Republic of China
| | - Zijing Lei
- Key Laboratory for the Physics & Chemistry of Nanodevices, and Department of Electronics, Peking University, Beijing, 100871 People’s Republic of China
| | - Jingkun Guo
- Key Laboratory for the Physics & Chemistry of Nanodevices, and Department of Electronics, Peking University, Beijing, 100871 People’s Republic of China
| | - Jie Huang
- Institute of Microelectronics, Peking University, Beijing, 100871 People’s Republic of China
| | - Wei Wang
- Institute of Microelectronics, Peking University, Beijing, 100871 People’s Republic of China
| | - Uta Reibetanz
- Medical Faculty, Institute for Medical Physics and Biophysics, University of Leipzig, 04103 Leipzig, Germany
| | - Shengyong Xu
- Key Laboratory for the Physics & Chemistry of Nanodevices, and Department of Electronics, Peking University, Beijing, 100871 People’s Republic of China
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10
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Qin L, Xu Y, Han H, Liu M, Chen K, Wang S, Wang J, Xu J, Li L, Guo X. β-Lactoglobulin (BLG) binding to highly charged cationic polymer-grafted magnetic nanoparticles: Effect of ionic strength. J Colloid Interface Sci 2015; 460:221-9. [DOI: 10.1016/j.jcis.2015.08.056] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 08/18/2015] [Accepted: 08/22/2015] [Indexed: 01/01/2023]
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11
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Cell-penetrating compounds preferentially bind glycosaminoglycans over plasma membrane lipids in a charge density- and stereochemistry-dependent manner. Biophys Chem 2015; 207:40-50. [DOI: 10.1016/j.bpc.2015.08.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 08/14/2015] [Accepted: 08/17/2015] [Indexed: 11/19/2022]
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12
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Chamieh J, Koval D, Besson A, Kašička V, Cottet H. Generalized polymer effective charge measurement by capillary isotachophoresis. J Chromatogr A 2014; 1370:255-62. [DOI: 10.1016/j.chroma.2014.10.025] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2014] [Revised: 10/03/2014] [Accepted: 10/09/2014] [Indexed: 12/22/2022]
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13
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Studying glycosaminoglycan-protein interactions using capillary electrophoresis. Methods Mol Biol 2014; 1229:355-75. [PMID: 25325965 DOI: 10.1007/978-1-4939-1714-3_28] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Methods for studying interactions between glycosaminoglycans (GAGs) and proteins have assumed considerable significance as their biological importance increases. Capillary electrophoresis (CE) is a powerful method to study these interactions due to its speed, high efficiency, and low sample/reagent consumption. In addition, CE works effectively under a wide range of physiologically relevant conditions. This chapter presents state-of-the-art on CE methods for studying GAG-protein interactions including affinity capillary electrophoresis (ACE), capillary zone electrophoresis (CZE), frontal analysis (FA)/frontal analysis continuous capillary electrophoresis (FACCE), and capillary electrokinetic chromatography (CEC) with detailed experimental protocols for ACE and CZE methods.
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14
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Minsky BB, Zheng B, Dubin PL. Inhibition of antithrombin and bovine serum albumin native state aggregation by heparin. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:278-287. [PMID: 24313340 DOI: 10.1021/la4039232] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Protein native state aggregation, a major problem in pharmaceutical and biological processes, has been addressed pharmacologically by the addition of protein-binding excipients. Heparin (Hp), a highly sulfated polysaccharide, interacts with numerous proteins with moderate to high affinity, but reports about its effect on protein aggregation are contradictory. We studied the pH dependence of the aggregation of antithrombin (AT) and bovine serum albumin (BSA) in the presence and absence of heparin. High-precision turbidimetry showed strong aggregation for both AT and BSA in I = 10 mM NaCl, conditions at which electrostatically driven Hp binding and aggregation both occur, with more obvious aggregation of heparin-free AT appearing as larger aggregate size. Aggregation of AT was dramatically inhibited at Hp: protein 6:1 (mole ratio); however, the effect at 0.5:1 Hp:protein was greater for BSA. Frontal analysis capillary electrophoresis showed a much larger equilibrium association constant Kobs between Hp and AT, in accord with the onset of Hp binding at a higher pH; both effects are explained by the higher charge density of the positive domain for AT as revealed by modeling with DelPhi. The corresponding modeling images showed that these domains persist at high salt only for AT, consistent with the 160-fold drop in Kobs at 100 mM salt for BSA-Hp binding. The smaller inhibition effect for AT arises from the tendency of its uncomplexed monomer to form larger aggregates more rapidly, but the stronger binding of Hp to AT does not facilitate Hp-induced aggregate dissolution which occurs more readily for BSA. This can be attributed to the higher density of AT aggregates evidenced by higher fractal dimensions. Differences between inhibition and reversal by Hp arise because the former may depend on the stage at which Hp enters the aggregation process and the latter on aggregate size and morphology.
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Affiliation(s)
- Burcu Baykal Minsky
- Department of Chemistry, University of Massachusetts , Amherst, Massachusetts, 01003, United States
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15
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Minsky BB, Nguyen TV, Peyton SR, Kaltashov IA, Dubin PL. Heparin decamer bridges a growth factor and an oligolysine by different charge-driven interactions. Biomacromolecules 2013; 14:4091-8. [PMID: 24107074 DOI: 10.1021/bm401227p] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Full-length heparin is widely used in tissue engineering applications due its multiple protein-binding sites that allow it to retain growth factor affinity while associating with oligopeptide components of the tissue scaffold. However, the extent to which oligopeptide coupling interferes with cognate protein binding is difficult to predict. To investigate such simultaneous interactions, we examined a well-defined ternary system comprised of acidic fibroblast growth factor (FGF), tetralysine (K4), with a heparin decamer (dp10) acting as a noncovalent coupler. Electrospray ionization mass spectrometry was used to assess binding affinities and complex stoichiometries as a function of ionic strength for dp10·K4 and FGF·dp10. The ionic strength dependence of K4·dp10 formation is qualitatively consistent with binding driven by the release of condensed counterions previously suggested for native heparin with divalent oligopeptides (Mascotti, D. P.; Lohman, T. M. Biochemistry 1995, 34, 2908-2915). On the other hand, FGF binding displays more complex ionic strength dependence, with higher salt resistance. Remarkably, dp10 that can bind two FGF molecules can only bind one tetralysine. The limited binding of K4 to dp10 suggests that the tetralysine might not block growth factor binding, and the 1:1:1 ternary complex is indeed observed. The analysis of mass distribution of the bound dp10 chains in FGF·dp10, FGF2·dp10, and FGF·dp10·K4 complexes indicated that higher degrees of dp10 sulfation promote the formation of FGF2·dp10 and FGF·dp10·K4. Thus, the selectivity of appropriately chosen short heparin chains could be used to modulate growth factor sequestration and release in a way not feasible with heterogeneous native heparin. In support of this, human hepatocellular carcinoma cells (HEP3Bs) treated with FGF·dp10·K4 were found to exhibit biological activity similar to cells treated with FGF.
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Affiliation(s)
- Burcu Baykal Minsky
- Departments of †Chemistry and ‡Chemical Engineering, University of Massachusetts , 710 North Pleasant Street, Amherst, Massachusetts 01003, United States
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16
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Size and charge characterization of polymeric drug delivery systems by Taylor dispersion analysis and capillary electrophoresis. Anal Bioanal Chem 2013; 405:5369-79. [PMID: 23624952 DOI: 10.1007/s00216-013-6972-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 04/03/2013] [Accepted: 04/04/2013] [Indexed: 12/21/2022]
Abstract
In this work, Taylor dispersion analysis and capillary electrophoresis were used to characterize the size and charge of polymeric drug delivery nanogels based on polyglutamate chains grafted with hydrophobic groups of vitamin E. The hydrophobic vitamin E groups self-associate in water to form small hydrophobic nanodomains that can incorporate small drugs or therapeutic proteins. Taylor dispersion analysis is well suited to determine the weight average hydrodynamic radius of nanomaterials and to get information on the size polydispersity of polymeric samples. The effective charge was determined either from electrophoretic mobility and hydrodynamic radius using electrophoretic modeling (three different approaches were compared), or by indirect UV detection in capillary electrophoresis. The influence of vitamin E hydrophobicity on the polymer effective charge has been studied. The presence of vitamin E leads to a drastic decrease in polymer effective charge in comparison to non-modified polyglutamate. Finally, the electrophoretic behavior of polyglutamate backbone grafted with hydrophobic vitamin E (pGVE) nanogels according to the ionic strength was investigated using the recently proposed slope plot approach. It was deduced that the pGVE nanogels behave electrophoretically as polyelectrolytes which is in good agreement with the high water content of the nanogels.
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17
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Minsky BB, Atmuri A, Kaltashov IA, Dubin PL. Counterion Condensation on Heparin Oligomers. Biomacromolecules 2013; 14:1113-21. [DOI: 10.1021/bm400006g] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Burcu Baykal Minsky
- Department
of Chemistry, University of Massachusetts, 710 North Pleasant Street,
Amherst, Massachusetts, 01003, United States
| | - Anand Atmuri
- Department of Chemical Engineering, University of Massachusetts, Amherst, Massachusetts,
01003, United States
| | - Igor A. Kaltashov
- Department
of Chemistry, University of Massachusetts, 710 North Pleasant Street,
Amherst, Massachusetts, 01003, United States
| | - Paul L. Dubin
- Department
of Chemistry, University of Massachusetts, 710 North Pleasant Street,
Amherst, Massachusetts, 01003, United States
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18
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Lima MA, Hughes AJ, Veraldi N, Rudd TR, Hussain R, Brito AS, Chavante SF, Tersariol II, Siligardi G, Nader HB, Yates EA. Antithrombin stabilisation by sulfated carbohydrates correlates with anticoagulant activity. MEDCHEMCOMM 2013. [DOI: 10.1039/c3md00048f] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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19
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Ibrahim A, Ohshima H, Allison SA, Cottet H. Determination of effective charge of small ions, polyelectrolytes and nanoparticles by capillary electrophoresis. J Chromatogr A 2012; 1247:154-64. [PMID: 22683187 DOI: 10.1016/j.chroma.2012.05.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Revised: 04/27/2012] [Accepted: 05/01/2012] [Indexed: 11/28/2022]
Abstract
In this paper, a systematic and comparative study related to the effective charge determination of three kinds of solutes (small ions, polyelectrolytes and nanoparticles) was performed. Four approaches were compared regarding their conditions of validity and their advantages/disadvantages. Three of them allow the effective charge determination from the electrophoretic mobility and the hydrodynamic radius of the solutes using electrophoretic mobility modelings based on Nernst-Einstein (NE), O'Brien-White-Ohshima (OWO) and Yoon and Kim (YK) equations. Electrophoretic mobility and hydrodynamic radius were determined by capillary electrophoresis and Taylor dispersion analysis, respectively, using the same instrumentation in similar conditions, on a large set of samples. A fourth experimental approach based on the sensitivity of detection in indirect UV detection mode (IUV) was compared to the previously mentioned methods. OWO and YK modelings are well adapted for the effective charge determination of small ions and nanoparticles, while IUV is the only method adapted for polyelectrolytes.
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Affiliation(s)
- Amal Ibrahim
- Institut des Biomolécules Max Mousseron, UMR 5247 CNRS, Université de Montpellier 1-2, Place Eugène Bataillon CC 1706, 34095 Montpellier Cedex 5, France
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20
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Uniewicz KA, Ori A, Rudd TR, Guerrini M, Wilkinson MC, Fernig DG, Yates EA. Following protein-glycosaminoglycan polysaccharide interactions with differential scanning fluorimetry. Methods Mol Biol 2012; 836:171-182. [PMID: 22252635 DOI: 10.1007/978-1-61779-498-8_12] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Studies of the structural changes invoked in proteins by the binding of the glycosaminoglycan (GAG) polysaccharide portion of proteoglycans are of increasing importance to research in a wide range of fields, from biochemistry and molecular biology to biotechnology and medicine. One important aspect is the degree of stabilisation or destabilisation induced in a protein by the binding of these anionic materials, and this can affect enzyme activity, the stability of complexes, folding and the formation of aggregates, including those in neurodegenerative processes. A simple method, able to determine the effect of interactions with GAG polysaccharides on protein stability is described, based on the propensity of a fluorescent dye-Sypro™ Orange-to present differentiable fluorescence emission spectra following contact with exposed core amino acid residues. The method requires only commonly available and inexpensive equipment and is suitable for a multi-well format, allowing multiple readings to be made simultaneously.
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21
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Mulloy B, Khan S, Perkins SJ. Molecular architecture of heparin and heparan sulfate: Recent developments in solution structural studies. PURE APPL CHEM 2011. [DOI: 10.1351/pac-con-11-10-27] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The study of the relationship between the complex structures and numerous physiological functions of the glycosaminoglycans (GAGs) heparin and heparan sulfate (HS) has continued to thrive in the past decade. Though it is clear that the monosaccharide sequences of these polysaccharides must determine their ability to modulate the action of growth factors, morphogens, chemokines, cytokines, and many other extracellular proteins, the exact details of this dependence still prove elusive. Sequence determines the 3D structure of GAGs at more than one level; detailed sequences of highly sulfated regions may influence affinity for specific proteins in some cases, but in addition attention has been called to the importance of the length and spacing of these highly sulfated sequences, which are separated by unsulfated domains. Within the sulfated “S-domains”, the internal dynamics of the conformationally flexible iduronate pyranose ring have continued to interest NMR spectroscopists and molecular modelers. New studies of the relative degrees of flexibility of sulfated and unsulfated domains lead to an overall model of heparin/HS in which protein-binding, highly sulfated S-domains with well-defined conformations are separated by more flexible NA-domains.
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22
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Schmitt C, Turgeon SL. Protein/polysaccharide complexes and coacervates in food systems. Adv Colloid Interface Sci 2011; 167:63-70. [PMID: 21056401 DOI: 10.1016/j.cis.2010.10.001] [Citation(s) in RCA: 541] [Impact Index Per Article: 41.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2010] [Accepted: 10/08/2010] [Indexed: 11/29/2022]
Abstract
Since the pioneering work of Bungenberg de Jong and co-workers on gelatin-acacia gum complex coacervation in the 1920-40s, protein/polysaccharide complexes and coacervates have received increasing research interest in order to broaden the possible food applications. This review focuses on the main research streams followed in this field during the last 12 years regarding: i) the parameters influencing the formation of complexes and coacervates in protein-polysaccharide systems; ii) the characterization of the kinetics of phase separation and multi-scale structure of the complexes and coacervates; and iii) the investigation of the functional properties of complexes and coacervates in food applications. This latter section encompasses various technological aspects, namely: the viscosifying and gelling ability, the foaming and emulsifying ability and finally, the stabilization and release of bioactives or sensitive compounds.
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Affiliation(s)
- Christophe Schmitt
- Department of Food Science and Technology, Nestlé Research Center, Lausanne, Switzerland.
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23
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Xu Y, Mazzawi M, Chen K, Sun L, Dubin PL. Protein Purification by Polyelectrolyte Coacervation: Influence of Protein Charge Anisotropy on Selectivity. Biomacromolecules 2011; 12:1512-22. [DOI: 10.1021/bm101465y] [Citation(s) in RCA: 166] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
| | | | - Kaimin Chen
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai, 200237, P. R. China
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24
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Jones CJ, Beni S, Limtiaco JFK, Langeslay DJ, Larive CK. Heparin characterization: challenges and solutions. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2011; 4:439-465. [PMID: 21469955 DOI: 10.1146/annurev-anchem-061010-113911] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Although heparin is an important and widely prescribed pharmaceutical anticoagulant, its high degree of sequence microheterogeneity and size polydispersity make molecular-level characterization challenging. Unlike nucleic acids and proteins that are biosynthesized through template-driven assembly processes, heparin and the related glycosaminoglycan heparan sulfate are actively remodeled during biosynthesis through a series of enzymatic reactions that lead to variable levels of O- and N-sulfonation and uronic acid epimers. As summarized in this review, heparin sequence information is determined through a bottom-up approach that relies on depolymerization reactions, size- and charge-based separations, and sensitive mass spectrometric and nuclear magnetic resonance experiments to determine the structural identity of component oligosaccharides. The structure-elucidation process, along with its challenges and opportunities for future analytical improvements, is reviewed and illustrated for a heparin-derived hexasaccharide.
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Affiliation(s)
- Christopher J Jones
- Department of Chemistry, University of California, Riverside, California 92521, USA.
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25
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Sperber BLHM, Cohen Stuart MA, Schols HA, Voragen AGJ, Norde W. Overall Charge and Local Charge Density of Pectin Determines the Enthalpic and Entropic Contributions to Complexation with β-Lactoglobulin. Biomacromolecules 2010; 11:3578-83. [DOI: 10.1021/bm1010432] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Bram L. H. M. Sperber
- Laboratory of Food Chemistry, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands, Laboratory of Physical Chemistry and Colloid Science, Wageningen University, Drijenplein 6, 6703HB, Wageningen, The Netherlands, and Department of Biomedical Engineering, University Medical Center Groningen and University of Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Martien A. Cohen Stuart
- Laboratory of Food Chemistry, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands, Laboratory of Physical Chemistry and Colloid Science, Wageningen University, Drijenplein 6, 6703HB, Wageningen, The Netherlands, and Department of Biomedical Engineering, University Medical Center Groningen and University of Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Henk A. Schols
- Laboratory of Food Chemistry, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands, Laboratory of Physical Chemistry and Colloid Science, Wageningen University, Drijenplein 6, 6703HB, Wageningen, The Netherlands, and Department of Biomedical Engineering, University Medical Center Groningen and University of Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Alphons G. J. Voragen
- Laboratory of Food Chemistry, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands, Laboratory of Physical Chemistry and Colloid Science, Wageningen University, Drijenplein 6, 6703HB, Wageningen, The Netherlands, and Department of Biomedical Engineering, University Medical Center Groningen and University of Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Willem Norde
- Laboratory of Food Chemistry, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands, Laboratory of Physical Chemistry and Colloid Science, Wageningen University, Drijenplein 6, 6703HB, Wageningen, The Netherlands, and Department of Biomedical Engineering, University Medical Center Groningen and University of Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
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26
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Silva RA, Urzúa MD, Petri DFS, Dubin PL. Protein adsorption onto polyelectrolyte layers: effects of protein hydrophobicity and charge anisotropy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:14032-14038. [PMID: 20672852 DOI: 10.1021/la102254g] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Ellipsometry was used to investigate the influence of ionic strength (I) and pH on the adsorption of bovine serum albumin (BSA) or beta-lactoglobulin (BLG) onto preabsorbed layers of two polycations: poly(diallyldimethylammonium chloride) (PDADMAC) or poly(4-vinylpyridine bromide) quaternized with linear aliphatic chains of two (QPVP-C2) or five (QPVP-C5) carbons. Comparisons among results for the three polycations reveal hydrophobic interactions, while comparisons between BSA and BLG-proteins of very similar isoelectric points (pI)-indicate the importance of protein charge anisotropy. At pH close to pI, the ionic strength dependence of the adsorbed amount of protein (Gamma) displayed maxima in the range 10 < I < 25 mM corresponding to Debye lengths close to the protein radii. Visualization of protein charge by Delphi suggested that these ionic strength conditions corresponded to suppression of long-range repulsion between polycations and protein positive domains, without diminution of short-range attraction between polycation segments and locally negative protein domains, in a manner similar to the behavior of PE-protein complexes in solution. (1-4) This description was consistent with the disappearance of the maxima at pH either above or below pI. In the former case, Gamma values decrease exponentially with I(1/2), due to screening of attractions, while in the latter case adsorption of both proteins decreased at low I due to strong repulsion. Close to or below pI both proteins adsorbed more strongly onto QPVP-C5 than onto QPVP-C2 or PDADMAC due to hydrophobic interactions with the longer alkyl group. Above pI, the adsorption was more pronounced with PDADMAC because these chains may assume more loosely bound layers due to lower linear charge density.
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Affiliation(s)
- Rubens A Silva
- Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
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27
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Seyrek E, Dubin P. Glycosaminoglycans as polyelectrolytes. Adv Colloid Interface Sci 2010; 158:119-29. [PMID: 20444439 DOI: 10.1016/j.cis.2010.03.001] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2009] [Revised: 02/27/2010] [Accepted: 03/03/2010] [Indexed: 02/02/2023]
Abstract
One of the barriers to understanding structure-property relations for glycosaminoglycans has been the lack of constructive interplay between the principles and methodologies of the life sciences (molecular biology, biochemistry and cell biology) and the physical sciences, particularly in the field of polyelectrolytes. To address this, we first review the similarities and differences between the physicochemical properties of GAGs and other statistical chain polyelectrolytes of both natural and abioitic origin. Since the biofunctionality and regulation of the structures of GAGs is intimately connected with interactions with their cognate proteins, we particularly compare and contrast aspects of protein binding, i.e. effects of both GAGs and other polyelectrolytes on protein stability, protein aggregation and phase behavior. The protein binding affinities and their dependences on pH and ionic strength for the two groups are discussed not only in terms of observable differences, but also with regard to contrasting descriptions of the bound state and the role of electrostatics. We conclude that early studies of the heparin-Antithromin system, proceeding to a large extent through the methods and models of protein chemistry and drug discovery, established not only many enabling precedents but also constraining paradigms. Current studies on heparan sulfate and chondroitin sulfate seem to reflect a more ecumenical view likely to be more compatible with concepts from physical and polymer chemistry.
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Affiliation(s)
- Emek Seyrek
- CNRS, Insitut Charles Sadron, 23 Rue Loess, BP 84047, F-67037 Strasbourg 2, France
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28
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Mjahed H, Voegel JC, Chassepot A, Senger B, Schaaf P, Boulmedais F, Ball V. Turbidity diagrams of polyanion/polycation complexes in solution as a potential tool to predict the occurrence of polyelectrolyte multilayer deposition. J Colloid Interface Sci 2010; 346:163-71. [DOI: 10.1016/j.jcis.2010.02.042] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2010] [Revised: 02/17/2010] [Accepted: 02/18/2010] [Indexed: 11/30/2022]
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29
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Naimy H, Leymarie N, Zaia J. Screening for anticoagulant heparan sulfate octasaccharides and fine structure characterization using tandem mass spectrometry. Biochemistry 2010; 49:3743-52. [PMID: 20345121 DOI: 10.1021/bi100135d] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Heparan sulfate (HS) is a sulfated glycosaminoglycan located on the surface and extracellular matrix of mammalian cells. HS is constituted of highly N-sulfated domains (NS domains) interrupted by lower sulfation domains. The arrangement of these domains dictates the function of HS which is mainly involved in binding proteins and regulating their biological activities. Heparin, a heparan sulfate analogue present in mast cells, resembles the NS domains of HS but lacks the alternating high and low sulfation architecture. Because the NS domains that range up to hexadecasaccharide in size are the main protein binders, heparin has been used as a model for HS in protein binding studies. Heparan sulfate, however, is the more physiologically relevant modulator of growth factor-receptor interactions. In this work, liquid chromatography and mass spectrometry (LC-MS) were used to compare the compositions of affinity-purified heparin and HS octasaccharides with anticoagulant activities versus library octasaccharides. The fine structures of the biologically active HS compositions were then compared against those of library octasaccharides using low-energy collision-induced dissociation tandem mass spectrometry. This approach confirmed isomeric enrichment of these compositions and, most importantly, produces ions diagnostic of their biological activity.
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Affiliation(s)
- Hicham Naimy
- Department of Biochemistry, Boston University School of Medicine, 670 Albany Street, Boston, Massachusetts 02118, USA
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30
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Rullo A, Nitz M. Importance of the spatial display of charged residues in heparin-peptide interactions. Biopolymers 2010; 93:290-8. [PMID: 19885920 DOI: 10.1002/bip.21339] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Many studies have examined consensus sequences required for protein-glycosaminoglycan interactions. Through the synthesis of helical heparin binding peptides, this study probes the relationship between spatial arrangement of positive charge and heparin binding affinity. Peptides with a linear distribution of positive charge along one face of the alpha-helix had the highest affinity for heparin. Moving the basic residues away from a single face resulted in drastic changes in heparin binding affinity of up to three orders of magnitude. These findings demonstrate that amino acid sequences, different from the known heparin binding consensus sequences, will form high affinity protein-heparin binding interactions when the charged residues are aligned linearly.
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Affiliation(s)
- Anthony Rullo
- Department of Chemistry, University of Toronto, Toronto, ON, Canada
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31
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Rudd TR, Uniewicz KA, Ori A, Guimond SE, Skidmore MA, Gaudesi D, Xu R, Turnbull JE, Guerrini M, Torri G, Siligardi G, Wilkinson MC, Fernig DG, Yates EA. Comparable stabilisation, structural changes and activities can be induced in FGF by a variety of HS and non-GAG analogues: implications for sequence-activity relationships. Org Biomol Chem 2010; 8:5390-7. [DOI: 10.1039/c0ob00246a] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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32
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Abstract
It was nearly 100 years since heparin was discovered, but the role of this widely used anticoagulant is still remarkably thought provoking now. During pathological processes such as atherosclerosis, inflammation, cancer and infection, phenomena of cell adhesion are ubiquitous and complicated. Heparin exerts anti-adhesion activity appearing as a common mechanism of its potential polypharmacology in those diseases. Furthermore, heparin can bind a variety of signalling molecules such as growth factors, cell surface proteins of pathogens and most notably, cell adhesion molecules. These signalling molecules are involved in cell communication, acting as ligands, receptors and second messengers. Considering that heparan sulphate glycosaminoglycan is increasingly recognized as a key mediator in many cellular processes, the structural similarity with heparan sulphate suggests that heparin is a multifunctional intervenor in cell communication.
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Affiliation(s)
- Xianxiang Xu
- Department of Pharmacology of Chinese Materia Medica, China Pharmaceutical University, Nanjing, China
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33
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Ball V, Maechling C. Isothermal microcalorimetry to investigate non specific interactions in biophysical chemistry. Int J Mol Sci 2009; 10:3283-3315. [PMID: 20111693 PMCID: PMC2812836 DOI: 10.3390/ijms10083283] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Revised: 07/21/2009] [Accepted: 07/24/2009] [Indexed: 01/28/2023] Open
Abstract
Isothermal titration microcalorimetry (ITC) is mostly used to investigate the thermodynamics of “specific” host-guest interactions in biology as well as in supramolecular chemistry. The aim of this review is to demonstrate that ITC can also provide useful information about non-specific interactions, like electrostatic or hydrophobic interactions. More attention will be given in the use of ITC to investigate polyelectrolyte-polyelectrolyte (in particular DNA-polycation), polyelectrolyte-protein as well as protein-lipid interactions. We will emphasize that in most cases these “non specific” interactions, as their definition will indicate, are favoured or even driven by an increase in the entropy of the system. The origin of this entropy increase will be discussed for some particular systems. We will also show that in many cases entropy-enthalpy compensation phenomena occur.
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Affiliation(s)
- Vincent Ball
- Institut National de la Santé et de la Recherche Médicale, Unité mixte de recherche 977, 11 rue Humann, 67085 Strasbourg Cédex, France
- Université de Strasbourg, Faculté de Chirurgie Dentaire, 1 Place de l’Hôpital, 67000 Strasbourg, France
- Author to whom correspondence should be addressed; E-Mail:
; Tel. +33-3-90-24-32-58; Fax: +33-3-88-90-24-33-79
| | - Clarisse Maechling
- Laboratoire d’Innovation Thérapeutique, Unité Mixte de Recherche 7200 CNRS - Université de Strasbourg, Faculté de Pharmacie, 74 route du Rhin BP 60024, F-67401 ILLKIRCH Cedex, France; E-Mail:
(C.M.)
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34
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Henry BL, Connell J, Liang A, Krishnasamy C, Desai UR. Interaction of antithrombin with sulfated, low molecular weight lignins: opportunities for potent, selective modulation of antithrombin function. J Biol Chem 2009; 284:20897-908. [PMID: 19497853 DOI: 10.1074/jbc.m109.013359] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Antithrombin, a major regulator of coagulation and angiogenesis, is known to interact with several natural sulfated polysaccharides. Previously, we prepared sulfated low molecular weight variants of natural lignins, called sulfated dehydrogenation polymers (DHPs) (Henry, B. L., Monien, B. H., Bock, P. E., and Desai, U. R. (2007) J. Biol. Chem. 282, 31891-31899), which have now been found to exhibit interesting antithrombin binding properties. Sulfated DHPs represent a library of diverse noncarbohydrate aromatic scaffolds that possess structures completely different from heparin and heparan sulfate. Fluorescence binding studies indicate that sulfated DHPs bind to antithrombin with micromolar affinity under physiological conditions. Salt dependence of binding affinity indicates that the antithrombin-sulfated DHP interaction involves a massive 80-87% non-ionic component to the free energy of binding. Competitive binding studies with heparin pentasaccharide, epicatechin sulfate, and full-length heparin indicate that sulfated DHPs bind to both the pentasaccharide-binding site and extended heparin-binding site of antithrombin. Affinity capillary electrophoresis resolves a limited number of peaks of antithrombin co-complexes suggesting preferential binding of selected DHP structures to the serpin. Computational genetic algorithm-based virtual screening study shows that only one sulfated DHP structure, out of the 11 present in a library of plausible sequences, bound in the heparin-binding site with a high calculated score supporting selectivity of recognition. Enzyme inhibition studies indicate that only one of the three sulfated DHPs studied is a potent inhibitor of free factor VIIa in the presence of antithrombin. Overall, the chemo-enzymatic origin and antithrombin binding properties of sulfated DHPs present novel opportunities for potent and selective modulation of the serpin function, especially for inhibiting the initiation phase of hemostasis.
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Affiliation(s)
- Brian L Henry
- Department of Medicinal Chemistry and Institute for Structural Biology and Drug Discovery, Virginia Commonwealth University, Richmond, Virginia 23298, USA
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35
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Liang A, Raghuraman A, Desai UR. Capillary electrophoretic study of small, highly sulfated, non-sugar molecules interacting with antithrombin. Electrophoresis 2009; 30:1544-51. [PMID: 19425011 PMCID: PMC2755545 DOI: 10.1002/elps.200800642] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Affinity CE (ACE) was used to study interactions of small, highly sulfated, aromatic molecules with antithrombin (AT). The high charge density of the small molecules induces differential migration of the complex resulting in a versatile method of assessing binding affinities, nature of interactions and site of binding on the inhibitor. Scatchard analysis of the interaction of three tetrahydroisoquinoline-based polysulfated molecules with AT results in monophasic profiles with affinities in the range of 40-60 microM in 20 mM sodium phosphate buffer, pH 7.4. For a pentasulfated molecule, a biphasic profile with affinities of 4.7 and 30 microM was observed. Measurement of K(D) as a function of ionic strength of the medium indicated that ionic and non-ionic forces contribute 2.4 and 1.9 kcal/mol, respectively, at pH 7.4 and 100 mM NaCl. Competitive binding studies showed that the tetrahydroisoquinoline-based molecules do not compete with a high-affinity heparin pentasaccharide. In contrast, the affinity of these tetrahydroisoquinoline derivatives decreases dramatically in the presence of an extended heparin-binding site ligand. Overall, ACE analysis of small, sulfated aromatic molecules interacting with AT is relatively easy and obviates the need for an external signal, e.g. fluorescence, for monitoring the interaction. In addition to affording biochemical knowledge, the small sample requirement and fast analysis time of ACE could be particularly advantageous for high-throughput screening of potential anticoagulants.
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Affiliation(s)
- Aiye Liang
- Department of Medicinal Chemistry and Institute for Structural Biology and Drug Discovery, Virginia Commonwealth University, Richmond, Virginia 23219
| | - Arjun Raghuraman
- Department of Medicinal Chemistry and Institute for Structural Biology and Drug Discovery, Virginia Commonwealth University, Richmond, Virginia 23219
| | - Umesh R. Desai
- Department of Medicinal Chemistry and Institute for Structural Biology and Drug Discovery, Virginia Commonwealth University, Richmond, Virginia 23219
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Anderot M, Nilsson M, Végvári Á, Moeller EH, van de Weert M, Isaksson R. Determination of dissociation constants between polyelectrolytes and proteins by affinity capillary electrophoresis. J Chromatogr B Analyt Technol Biomed Life Sci 2009; 877:892-6. [DOI: 10.1016/j.jchromb.2009.02.021] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2008] [Revised: 02/05/2009] [Accepted: 02/06/2009] [Indexed: 11/28/2022]
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Zaia J. On-line separations combined with MS for analysis of glycosaminoglycans. MASS SPECTROMETRY REVIEWS 2009; 28:254-72. [PMID: 18956477 PMCID: PMC4119066 DOI: 10.1002/mas.20200] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The glycosaminoglycan (GAG) family of polysaccharides includes the unsulfated hyaluronan and the sulfated heparin, heparan sulfate, keratan sulfate, and chondroitin/dermatan sulfate. GAGs are biosynthesized by a series of enzymes, the activities of which are controlled by complex factors. Animal cells alter their responses to different growth conditions by changing the structures of GAGs expressed on their cell surfaces and in extracellular matrices. Because this variation is a means whereby the functions of the limited number of protein gene products in animal genomes is elaborated, the phenotypic and functional assessment of GAG structures expressed spatially and temporally is an important goal in glycomics. On-line mass spectrometric separations are essential for successful determination of expression patterns for the GAG compound classes due to their inherent complexity and heterogeneity. Options include size exclusion, anion exchange, reversed phase, reversed phase ion pairing, hydrophilic interaction, and graphitized carbon chromatographic modes and capillary electrophoresis. This review summarizes the application of these approaches to on-line MS analysis of the GAG classes.
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Affiliation(s)
- Joseph Zaia
- Department of Biochemistry, Center for Biomedical Mass Spectrometry, Mass Spectrometry Resource, Boston University School of Medicine, Boston, MA 02118, USA.
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Guerrini M, Guglieri S, Casu B, Torri G, Mourier P, Boudier C, Viskov C. Antithrombin-binding octasaccharides and role of extensions of the active pentasaccharide sequence in the specificity and strength of interaction. Evidence for very high affinity induced by an unusual glucuronic acid residue. J Biol Chem 2008; 283:26662-75. [PMID: 18640975 PMCID: PMC3258914 DOI: 10.1074/jbc.m801102200] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2008] [Revised: 06/04/2008] [Indexed: 11/06/2022] Open
Abstract
The antithrombotic activity of low molecular weight heparins (LMWHs) is largely associated with the antithrombin (AT)-binding pentasaccharide sequence AGA(*)IA (GlcN(NAc/NS,6S)-GlcA-GlcN(NS,3,6S)-IdoUA(2S)-GlcN(NS,6S)). The location of the AGA(*)IA sequences along the LMWH chains is also expected to influence binding to AT. This study was aimed at investigating the role of the structure and molecular conformation of different disaccharide extensions on both sides of the AGA(*)IA sequence in modulating the affinity for AT. Four high purity octasaccharides isolated by size exclusion chromatography, high pressure liquid chromatography, and AT-affinity chromatography from the LMWH enoxaparin were selected for the study. All the four octasaccharides terminate at their nonreducing end with 4,5-unsaturated uronic acid residues (DeltaU). In two octasaccharides, AGA(*)IA was elongated at the reducing end by units IdoUA(2S)-GlcN(NS,6S) (OCTA-1) or IdoUA-GlcN(NAc,6S) (OCTA-2). In the other two octasaccharides (OCTA-3 and OCTA-4), AGA(*)IA was elongated at the nonreducing side by units GlcN(NS,6S)-IdoUA and GlcN(NS,6S)-GlcA, respectively. Extensions increased the affinity for AT of octasaccharides with respect to pentasaccharide AGA(*)IA, as also confirmed by fluorescence titration. Two-dimensional NMR and docking studies clearly indicated that, although elongation of the AGA(*)IA sequence does not substantially modify the bound conformation of the AGA(*)IA segment, extensions promote additional contacts with the protein. It should be noted that, as not previously reported, the unusual GlcA residue that precedes the AGA(*)IA sequence in OCTA-4 induced an unexpected 1 order of magnitude increase in the affinity to AT with respect to its IdoUA-containing homolog OCTA-3. Such a residue was found to orientate its two hydroxyl groups at close distance to residues of the protein. Besides the well established ionic interactions, nonionic interactions may thus contribute to strengthen oligosaccharide-AT complexes.
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Affiliation(s)
- Marco Guerrini
- “G. Ronzoni”
Institute for Chemical and Biochemical Research, via G. Colombo 81, 20133
Milan, Italy, Sanofi-Aventis, 13 Quai
Jules Guesde, 94403 Vitry sur Seine, France, and
CNRS UMR 7175, Département
Physicochimie et Pharmacochimie des Interactions Moléculaires et
Cellulaires, Faculté de Pharmacie, Université Louis Pasteur,
Strasbourg I, F 67401, France
| | - Sara Guglieri
- “G. Ronzoni”
Institute for Chemical and Biochemical Research, via G. Colombo 81, 20133
Milan, Italy, Sanofi-Aventis, 13 Quai
Jules Guesde, 94403 Vitry sur Seine, France, and
CNRS UMR 7175, Département
Physicochimie et Pharmacochimie des Interactions Moléculaires et
Cellulaires, Faculté de Pharmacie, Université Louis Pasteur,
Strasbourg I, F 67401, France
| | - Benito Casu
- “G. Ronzoni”
Institute for Chemical and Biochemical Research, via G. Colombo 81, 20133
Milan, Italy, Sanofi-Aventis, 13 Quai
Jules Guesde, 94403 Vitry sur Seine, France, and
CNRS UMR 7175, Département
Physicochimie et Pharmacochimie des Interactions Moléculaires et
Cellulaires, Faculté de Pharmacie, Université Louis Pasteur,
Strasbourg I, F 67401, France
| | - Giangiacomo Torri
- “G. Ronzoni”
Institute for Chemical and Biochemical Research, via G. Colombo 81, 20133
Milan, Italy, Sanofi-Aventis, 13 Quai
Jules Guesde, 94403 Vitry sur Seine, France, and
CNRS UMR 7175, Département
Physicochimie et Pharmacochimie des Interactions Moléculaires et
Cellulaires, Faculté de Pharmacie, Université Louis Pasteur,
Strasbourg I, F 67401, France
| | - Pierre Mourier
- “G. Ronzoni”
Institute for Chemical and Biochemical Research, via G. Colombo 81, 20133
Milan, Italy, Sanofi-Aventis, 13 Quai
Jules Guesde, 94403 Vitry sur Seine, France, and
CNRS UMR 7175, Département
Physicochimie et Pharmacochimie des Interactions Moléculaires et
Cellulaires, Faculté de Pharmacie, Université Louis Pasteur,
Strasbourg I, F 67401, France
| | - Christian Boudier
- “G. Ronzoni”
Institute for Chemical and Biochemical Research, via G. Colombo 81, 20133
Milan, Italy, Sanofi-Aventis, 13 Quai
Jules Guesde, 94403 Vitry sur Seine, France, and
CNRS UMR 7175, Département
Physicochimie et Pharmacochimie des Interactions Moléculaires et
Cellulaires, Faculté de Pharmacie, Université Louis Pasteur,
Strasbourg I, F 67401, France
| | - Christian Viskov
- “G. Ronzoni”
Institute for Chemical and Biochemical Research, via G. Colombo 81, 20133
Milan, Italy, Sanofi-Aventis, 13 Quai
Jules Guesde, 94403 Vitry sur Seine, France, and
CNRS UMR 7175, Département
Physicochimie et Pharmacochimie des Interactions Moléculaires et
Cellulaires, Faculté de Pharmacie, Université Louis Pasteur,
Strasbourg I, F 67401, France
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Nakamura Y, Miyatake R, Ueda M. Enantiodifferential Approach for the Detection of the Target Membrane Protein of the Jasmonate Glycoside that Controls the Leaf Movement ofAlbizzia saman. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200801820] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Nakamura Y, Miyatake R, Ueda M. Enantiodifferential Approach for the Detection of the Target Membrane Protein of the Jasmonate Glycoside that Controls the Leaf Movement ofAlbizzia saman. Angew Chem Int Ed Engl 2008; 47:7289-92. [DOI: 10.1002/anie.200801820] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Abstract
Complex natural polysaccharides, glycosaminoglycans (GAGs), are a class of ubiquitous macromolecules that exhibit a wide range of biological functions and participate and regulate multiple cellular events and (patho)physiological processes. They are generally present either as free chains (hyaluronic acid and bacterial acidic polysaccharides) or as side chains of proteoglycans (PGs; chondroitin/dermatan sulfate, heparin/heparan sulfate, and keratan sulfate) and are most often found in cell membranes and in the extracellular matrix. The recent emergence of modern analytical tools for their study has produced a virtual explosion in the field of glycomics. CE, due to its high resolving power and sensitivity, has been useful in the analysis of intact GAGs and GAG-derived oligosaccharides and disaccharides affording concentration and structural characterization data essential for understanding the biological functions of GAGs. In this review, novel off-line and on-line CE-MS and MS/MS methods for screening of GAG-derived oligosaccharides and disaccharides will be discussed.
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Affiliation(s)
- Nicola Volpi
- Department of Biologia Animale, Biological Chemistry Section, University of Modena and Reggio Emilia, Modena, Italy.
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Abzalimov RR, Dubin PL, Kaltashov IA. Glycosaminoglycans as Naturally Occurring Combinatorial Libraries: Developing a Mass Spectrometry-Based Strategy for Characterization of Anti-Thrombin Interaction with Low Molecular Weight Heparin and Heparin Oligomers. Anal Chem 2007; 79:6055-63. [PMID: 17658885 DOI: 10.1021/ac0710432] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Heparin is a densely charged polysaccharide, which is best known for its anticoagulant activity, although it also modulates a plethora of other biological processes. Unlike biopolymers whose synthesis is strictly controlled by a unique genetic template, heparin molecules exhibit a remarkable degree of structural heterogeneity, which poses a serious challenge for studies of heparin-protein interactions. This analytical challenge is often dealt with by reducing the enormous structural repertoire of heparin to a model small molecule. In this paper, we describe a different approach inspired by the experimental methodologies from the arsenal of combinatorial chemistry. Interaction of anti-thrombin III (AT) with heparinoids is studied using a mixture of oligoheparin molecules of fixed degree of polymerization, but varying chemical composition (heparin hexasaccharides obtained by size exclusion chromatography of an enzymatic digest of porcine intestinal heparin with bacterial heparinase), as well as a heparin-derived pharmaceutical preparation Tinzaparin (heparin oligosaccharides up to a 22-mer). AT binders are identified based on the results of ESI MS measurements of complexes formed by protein-oligoheparin association. Additionally, differential depletion of free heparin oligomers in solution in the presence of AT is used to verify the binding preferences. ESI MS characterization of oligoheparin-AT interaction under partially denaturing conditions allowed the conformer specificity of the protein-polyanion binding to be monitored. A model emerging from these studies invokes the notion of a well-defined binding site on AT, to which a flexible partner (heparin) adapts to maximize favorable intermolecular electrostatic interactions. This study demonstrates the enormous potential of ESI MS as an analytical tool to study the interactions of highly heterogeneous glycosaminoglycans with their cognate proteins outside of the commonly accepted reductionist paradigm, which reduces the intrinsic complexity of heparin by using structurally defined homogeneous low molecular weight mimetics.
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Affiliation(s)
- Rinat R Abzalimov
- Department of Chemistry, University of Massachusetts Amherst, 710 North Pleasant Street, Amherst, Massachusetts 01003, USA
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