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Yamaguchi Y, Yamaguchi T, Kato K. Structural Analysis of Oligosaccharides and Glycoconjugates Using NMR. ADVANCES IN NEUROBIOLOGY 2023; 29:163-184. [PMID: 36255675 DOI: 10.1007/978-3-031-12390-0_6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Carbohydrate chains play critical roles in cellular recognition and subsequent signal transduction in the nervous system. Furthermore, gangliosides are targets for various amyloidogenic proteins associated with neurodegenerative disorders. To better understand the molecular mechanisms underlying these biological phenomena, atomic views are essential to delineate dynamic biomolecular interactions. Nuclear magnetic resonance (NMR) spectroscopy provides powerful tools for studying structures, dynamics, and interactions of biomolecules at the atomic level. This chapter describes the basics of solution NMR techniques and their applications to the analysis of 3D structures and interactions of glycoconjugates in the nervous system.
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Affiliation(s)
- Yoshiki Yamaguchi
- Division of Structural Biology, Institute of Molecular Biomembrane and Glycobiology, Tohoku Medical and Pharmaceutical University, Sendai, Japan.
| | - Takumi Yamaguchi
- School of Materials Science, Japan Advanced Institute of Science and Technology, Nomi, Japan
- Graduate School of Pharmaceutical Sciences, Nagoya City University, Mizuho-ku, Nagoya, Japan
| | - Koichi Kato
- Graduate School of Pharmaceutical Sciences, Nagoya City University, Mizuho-ku, Nagoya, Japan.
- Exploratory Research Center on Life and Living Systems and Institute for Molecular Science, Okazaki, Japan.
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2
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Grothaus IL, Bussi G, Colombi Ciacchi L. Exploration, Representation, and Rationalization of the Conformational Phase Space of N-Glycans. J Chem Inf Model 2022; 62:4992-5008. [PMID: 36179122 DOI: 10.1021/acs.jcim.2c01049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Despite their fundamental biological relevance, structure-property relationships in N-glycans are fundamentally lacking, and their highly multidimensional compositional and conformational phase spaces remain largely unexplored. The torsional flexibility of the glycosidic linkages and the ring dynamics result in wide, rugged free-energy landscapes that are difficult to sample in molecular dynamics simulations. We show that a novel enhanced-sampling scheme combining replica exchange with solute and collective-variable tempering, enabling transitions over all relevant energy barriers, delivers converged distributions of solvated N-glycan conformers. Several dimensionality-reduction algorithms are compared and employed to generate conformational free-energy maps in two dimensions. Together with an originally developed conformation-based nomenclature scheme that uniquely identifies glycan conformers, our modeling procedure is applied to reveal the effect of chemical substitutions on the conformational ensemble of selected high-mannose-type and complex glycans. Moreover, the structure-prediction capabilities of two commonly used glycan force fields are assessed via the theoretical prediction of experimentally available nuclear magnetic resonance J-coupling constants. The results especially confirm the key role of ω and ψ torsion angles in discriminating between different conformational states and suggest an intriguing correlation between the torsional and ring-puckering degrees of freedom that may be biologically relevant.
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Affiliation(s)
- Isabell Louise Grothaus
- Hybrid Materials Interfaces Group, Bremen Center for Computational Materials Science and MAPEX Center for Materials and Processes, University of Bremen, 28359Bremen, Germany
| | - Giovanni Bussi
- Scuola Internazionale Superiore di Studi Avanzati (SISSA), 34136Trieste, Italy
| | - Lucio Colombi Ciacchi
- Hybrid Materials Interfaces Group, Bremen Center for Computational Materials Science and MAPEX Center for Materials and Processes, University of Bremen, 28359Bremen, Germany
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3
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Abstract
Glycoscience assembles all the scientific disciplines involved in studying various molecules and macromolecules containing carbohydrates and complex glycans. Such an ensemble involves one of the most extensive sets of molecules in quantity and occurrence since they occur in all microorganisms and higher organisms. Once the compositions and sequences of these molecules are established, the determination of their three-dimensional structural and dynamical features is a step toward understanding the molecular basis underlying their properties and functions. The range of the relevant computational methods capable of addressing such issues is anchored by the specificity of stereoelectronic effects from quantum chemistry to mesoscale modeling throughout molecular dynamics and mechanics and coarse-grained and docking calculations. The Review leads the reader through the detailed presentations of the applications of computational modeling. The illustrations cover carbohydrate-carbohydrate interactions, glycolipids, and N- and O-linked glycans, emphasizing their role in SARS-CoV-2. The presentation continues with the structure of polysaccharides in solution and solid-state and lipopolysaccharides in membranes. The full range of protein-carbohydrate interactions is presented, as exemplified by carbohydrate-active enzymes, transporters, lectins, antibodies, and glycosaminoglycan binding proteins. A final section features a list of 150 tools and databases to help address the many issues of structural glycobioinformatics.
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Affiliation(s)
- Serge Perez
- Centre de Recherche sur les Macromolecules Vegetales, University of Grenoble-Alpes, Centre National de la Recherche Scientifique, Grenoble F-38041, France
| | - Olga Makshakova
- FRC Kazan Scientific Center of Russian Academy of Sciences, Kazan Institute of Biochemistry and Biophysics, Kazan 420111, Russia
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4
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Rao RM, Dauchez M, Baud S. How molecular modelling can better broaden the understanding of glycosylations. Curr Opin Struct Biol 2022; 75:102393. [PMID: 35679802 DOI: 10.1016/j.sbi.2022.102393] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 03/31/2022] [Accepted: 04/18/2022] [Indexed: 11/03/2022]
Abstract
Glycosylations are among the most ubiquitous post-translational modifications (PTMs) in proteins, and the effects of their perturbations are seen in various diseases such as cancers, diabetes and arthritis to name a few. Yet they remain one of the most enigmatic aspects of protein structure and function. On the other hand, molecular modelling techniques have been rapidly bridging this knowledge gap since the last decade. In this review, we discuss how these techniques have proven to be indispensable for a better understanding of the role of glycosylations in glycoprotein structure and function.
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Affiliation(s)
- Rajas M Rao
- Université de Reims Champagne Ardenne, CNRS UMR 7369, MEDyC, Reims, 51687, France
| | - Manuel Dauchez
- Université de Reims Champagne Ardenne, CNRS UMR 7369, MEDyC, Reims, 51687, France.
| | - Stéphanie Baud
- Université de Reims Champagne Ardenne, CNRS UMR 7369, MEDyC, Reims, 51687, France
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5
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Conformational preferences of triantennary and tetraantennary hybrid N-glycans in aqueous solution: Insights from 20 μs long atomistic molecular dynamic simulations. J Biomol Struct Dyn 2022; 41:3305-3320. [PMID: 35262462 DOI: 10.1080/07391102.2022.2047109] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In the current study, we have investigated the conformational dynamics of a triantennary (N-glycan1) and tetraantennary (N-glycan2) hybrid N-glycans found on the surface of the HIV glycoprotein using 20 μs long all-atom molecular dynamics (MD) simulations. The main objective of the present study is to elucidate the influence of adding a complex branch on the overall glycan structural dynamics. Our investigation suggests that the average RMSD value increases when a complex branch is added to N-glycan1. However, the RMSD distribution is relatively wider in the case of N-glycan1 compared to N-glycan2, which indicates that multiple complex branches restrict the conformational variability of glycans. A similar observation is obtained from the principal component analysis of both glycans. All the puckering states (4C1 to 1C4) of each monosaccharide except mannose are sampled in our simulations, although the 4C1 chair form is energetically more favorable than 1C4. In N-glycan1, the 1-6 linkage in the mannose branch [Man(9)-α(1-6)-Man(5)] stays in the gauche-gauche cluster, whereas it moves towards trans-gauche in N-glycan2. For both glycans, mannose branches are more flexible than the complex branches, and adding a complex branch does not influence the dynamics of the mannose branches. We have noticed that the end-to-end distance of the complex branch shortens by ∼ 10 Å in the presence of another complex branch. This suggests that in the presence of an additional complex branch, the other complex branch adopts a close folded structure. All these conformational changes involve the selective formation of inter-residue and water-mediated hydrogen-bond networks.
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6
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Shirakawa A, Manabe Y, Marchetti R, Yano K, Masui S, Silipo A, Molinaro A, Fukase K. Chemical Synthesis of Sialyl
N
‐Glycans and Analysis of Their Recognition by Neuraminidase. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202111035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Asuka Shirakawa
- Department of Chemistry Graduate School of Science Osaka University 1-1 Machikaneyama, Toyonaka Osaka 560-0043 Japan
| | - Yoshiyuki Manabe
- Department of Chemistry Graduate School of Science Osaka University 1-1 Machikaneyama, Toyonaka Osaka 560-0043 Japan
- Core for Medicine and Science Collaborative Research and Education Project Research Center for Fundamental Sciences Graduate School of Science Osaka University 1-1 Machikaneyama, Toyonaka Osaka 560-0043 Japan
| | - Roberta Marchetti
- Department of Chemical Science University of Naples Federico II Via Cinthia 4 80126 Naples Italy
| | - Kumpei Yano
- Department of Chemistry Graduate School of Science Osaka University 1-1 Machikaneyama, Toyonaka Osaka 560-0043 Japan
| | - Seiji Masui
- Department of Chemistry Graduate School of Science Osaka University 1-1 Machikaneyama, Toyonaka Osaka 560-0043 Japan
| | - Alba Silipo
- Department of Chemistry Graduate School of Science Osaka University 1-1 Machikaneyama, Toyonaka Osaka 560-0043 Japan
- Department of Chemical Science University of Naples Federico II Via Cinthia 4 80126 Naples Italy
| | - Antonio Molinaro
- Department of Chemistry Graduate School of Science Osaka University 1-1 Machikaneyama, Toyonaka Osaka 560-0043 Japan
- Department of Chemical Science University of Naples Federico II Via Cinthia 4 80126 Naples Italy
| | - Koichi Fukase
- Department of Chemistry Graduate School of Science Osaka University 1-1 Machikaneyama, Toyonaka Osaka 560-0043 Japan
- Core for Medicine and Science Collaborative Research and Education Project Research Center for Fundamental Sciences Graduate School of Science Osaka University 1-1 Machikaneyama, Toyonaka Osaka 560-0043 Japan
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7
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Shirakawa A, Manabe Y, Marchetti R, Yano K, Masui S, Silipo A, Molinaro A, Fukase K. Chemical Synthesis of Sialyl N-Glycans and Analysis of Their Recognition by Neuraminidase. Angew Chem Int Ed Engl 2021; 60:24686-24693. [PMID: 34520098 DOI: 10.1002/anie.202111035] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Indexed: 11/07/2022]
Abstract
The chemical synthesis of a fully sialylated tetraantennary N-glycan has been achieved for the first time by using the diacetyl strategy, in which NHAc is protected as NAc2 to improve reactivity by preventing intermolecular hydrogen bonds. Another key was the glycosylation to the branched mannose in an ether solvent, which promoted the desired glycosylation by stabilizing the oxocarbenium ion intermediate. Furthermore, high α-selectivity of these glycosylation reactions was realized by utilizing remote participation. Two asymmetrically deuterium labeled sialyl N-glycans were also synthesized by the same strategy. The synthesized N-glycans were used to probe the molecular basis of H1N1 neuraminidase recognition. The asymmetrically deuterated N-glycans revealed a difference in the recognition of sialic acid on each branch. Meanwhile, the tetraantennary N-glycan was used to evaluate the effects of multivalency and steric hinderance by forming branching structures.
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Affiliation(s)
- Asuka Shirakawa
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Yoshiyuki Manabe
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan.,Core for Medicine and Science Collaborative Research and Education, Project Research Center for Fundamental Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Roberta Marchetti
- Department of Chemical Science, University of Naples Federico II, Via Cinthia 4, 80126, Naples, Italy
| | - Kumpei Yano
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Seiji Masui
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Alba Silipo
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan.,Department of Chemical Science, University of Naples Federico II, Via Cinthia 4, 80126, Naples, Italy
| | - Antonio Molinaro
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan.,Department of Chemical Science, University of Naples Federico II, Via Cinthia 4, 80126, Naples, Italy
| | - Koichi Fukase
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan.,Core for Medicine and Science Collaborative Research and Education, Project Research Center for Fundamental Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
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8
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Shirakawa A, Manabe Y, Fukase K. Recent Advances in the Chemical Biology of N-Glycans. Molecules 2021; 26:molecules26041040. [PMID: 33669465 PMCID: PMC7920464 DOI: 10.3390/molecules26041040] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 02/08/2021] [Accepted: 02/14/2021] [Indexed: 12/19/2022] Open
Abstract
Asparagine-linked N-glycans on proteins have diverse structures, and their functions vary according to their structures. In recent years, it has become possible to obtain high quantities of N-glycans via isolation and chemical/enzymatic/chemoenzymatic synthesis. This has allowed for progress in the elucidation of N-glycan functions at the molecular level. Interaction analyses with lectins by glycan arrays or nuclear magnetic resonance (NMR) using various N-glycans have revealed the molecular basis for the recognition of complex structures of N-glycans. Preparation of proteins modified with homogeneous N-glycans revealed the influence of N-glycan modifications on protein functions. Furthermore, N-glycans have potential applications in drug development. This review discusses recent advances in the chemical biology of N-glycans.
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Affiliation(s)
- Asuka Shirakawa
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan;
| | - Yoshiyuki Manabe
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan;
- Core for Medicine and Science Collaborative Research and Education, Project Research Center for Fundamental Sciences, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan
- Correspondence: (Y.M.); (K.F.); Tel.: +81-6-6850-5391 (Y.M.); +81-6-6850-5388 (K.F.)
| | - Koichi Fukase
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan;
- Core for Medicine and Science Collaborative Research and Education, Project Research Center for Fundamental Sciences, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan
- Correspondence: (Y.M.); (K.F.); Tel.: +81-6-6850-5391 (Y.M.); +81-6-6850-5388 (K.F.)
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9
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Nakano M, Mishra SK, Tokoro Y, Sato K, Nakajima K, Yamaguchi Y, Taniguchi N, Kizuka Y. Bisecting GlcNAc Is a General Suppressor of Terminal Modification of N-glycan. Mol Cell Proteomics 2019; 18:2044-2057. [PMID: 31375533 PMCID: PMC6773561 DOI: 10.1074/mcp.ra119.001534] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 08/01/2019] [Indexed: 12/18/2022] Open
Abstract
Glycoproteins are decorated with complex glycans for protein functions. However, regulation mechanisms of complex glycan biosynthesis are largely unclear. Here we found that bisecting GlcNAc, a branching sugar residue in N-glycan, suppresses the biosynthesis of various types of terminal epitopes in N-glycans, including fucose, sialic acid and human natural killer-1. Expression of these epitopes in N-glycan was elevated in mice lacking the biosynthetic enzyme of bisecting GlcNAc, GnT-III, and was conversely suppressed by GnT-III overexpression in cells. Many glycosyltransferases for N-glycan terminals were revealed to prefer a nonbisected N-glycan as a substrate to its bisected counterpart, whereas no up-regulation of their mRNAs was found. This indicates that the elevated expression of the terminal N-glycan epitopes in GnT-III-deficient mice is attributed to the substrate specificity of the biosynthetic enzymes. Molecular dynamics simulations further confirmed that nonbisected glycans were preferentially accepted by those glycosyltransferases. These findings unveil a new regulation mechanism of protein N-glycosylation.
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Affiliation(s)
- Miyako Nakano
- Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashihiroshima, Hiroshima 739-8530, Japan
| | - Sushil K Mishra
- Glycoscience Group, National University of Ireland, Galway, Ireland; Structural Glycobiology Team, RIKEN-Max Planck Joint Research Center, Global Research Cluster, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Yuko Tokoro
- Center for Highly Advanced Integration of Nano and Life Sciences (G-CHAIN), Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Keiko Sato
- Disease Glycomics Team, RIKEN-Max Planck Joint Research Center, Global Research Cluster, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Kazuki Nakajima
- Division of Clinical Research Promotion and Support, Center for Research Promotion, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi 470-1192, Japan.
| | - Yoshiki Yamaguchi
- Structural Glycobiology Team, RIKEN-Max Planck Joint Research Center, Global Research Cluster, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; Synthetic Cellular Chemistry Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Naoyuki Taniguchi
- Disease Glycomics Team, RIKEN-Max Planck Joint Research Center, Global Research Cluster, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; Department of Glyco-Oncology and Medical Biochemistry, Osaka International Cancer Institute, 3-1-69 Otemae, Chuoku, Osaka 541-8567, Japan
| | - Yasuhiko Kizuka
- Center for Highly Advanced Integration of Nano and Life Sciences (G-CHAIN), Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan; Disease Glycomics Team, RIKEN-Max Planck Joint Research Center, Global Research Cluster, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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10
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Sugita Y, Kamiya M, Oshima H, Re S. Replica-Exchange Methods for Biomolecular Simulations. Methods Mol Biol 2019; 2022:155-177. [PMID: 31396903 DOI: 10.1007/978-1-4939-9608-7_7] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In this study, a replica-exchange method was developed to overcome conformational sampling difficulties in computer simulations of spin glass or other systems with rugged free-energy landscapes. This method was then applied to the protein-folding problem in combination with molecular dynamics (MD) simulation. Owing to its simplicity and sampling efficiency, the replica-exchange method has been applied to many other biological problems and has been continuously improved. The method has often been combined with other sampling techniques, such as umbrella sampling, free-energy perturbation, metadynamics, and Gaussian accelerated MD (GaMD). In this chapter, we first summarize the original replica-exchange molecular dynamics (REMD) method and discuss how new algorithms related to the original method are implemented to add new features. Heterogeneous and flexible structures of an N-glycan in a solution are simulated as an example of applications by REMD, replica exchange with solute tempering, and GaMD. The sampling efficiency of these methods on the N-glycan system and the convergence of the free-energy changes are compared. REMD simulation protocols and trajectory analysis using the GENESIS software are provided to facilitate the practical use of advanced simulation methods.
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Affiliation(s)
- Yuji Sugita
- Theoretical Molecular Science Laboratory, RIKEN Cluster for Pioneering Research, Saitama, Japan. .,Computational Biophysics Research Team, RIKEN Center for Computational Science, Kobe, Japan. .,Laboratory for Biomolecular Function Simulation, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan.
| | - Motoshi Kamiya
- Computational Biophysics Research Team, RIKEN Center for Computational Science, Kobe, Japan
| | - Hiraku Oshima
- Laboratory for Biomolecular Function Simulation, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
| | - Suyong Re
- Laboratory for Biomolecular Function Simulation, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
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11
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Glycan binding and specificity of viral influenza neuraminidases by classical molecular dynamics and replica exchange molecular dynamics simulations. J Biomol Struct Dyn 2018; 37:3354-3365. [DOI: 10.1080/07391102.2018.1514326] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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12
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Tachi Y, Okamoto Y, Okumura H. Conformational properties of an artificial GM1 glycan cluster based on a metal-ligand complex. J Chem Phys 2018; 149:135101. [PMID: 30292198 DOI: 10.1063/1.5045310] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
An artificial glycan cluster, in which 24 monosialotetrahexosylganglioside (GM1) glycans are transplanted to the interface of a metal-ligand complex, was recently proposed to investigate the interaction between GM1 glycan clusters and amyloidogenic proteins by NMR analysis. In this study, all-atom molecular dynamics simulations were performed to characterize the conformational properties of the artificial GM1 glycan cluster. We found that more than 65% of GM1 glycans are clustered by interchain hydrogen bonds. Interchain hydrogen bonds are mainly formed between Neu5Ac and Gal'. Pentamers were most frequently observed in the metal-ligand complex. GM1 glycans are tilted and hydrophobically interact with ligand moieties. The hydrophobic surface of the metal-ligand complex increases intrachain hydrogen bonds in each conformation of the GM1 glycans. The increase of intrachain hydrogen bonds stabilizes the local minimum conformations of the GM1 glycan in comparison with the monomeric one. Interchain hydrogen bonding between glycans and glycan-ligand hydrophobic interactions also contribute to this conformational stabilization. Our results provide the physicochemical properties of the new artificial GM1 glycan cluster under the thermal fluctuations for understanding its protein recognition and designing the drug material for amyloidogenic proteins.
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Affiliation(s)
- Yuhei Tachi
- Department of Physics, Graduate school of Science, Nagoya University, Nagoya, Aichi 464-8602, Japan
| | - Yuko Okamoto
- Structural Biology Research Center, Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602, Japan
| | - Hisashi Okumura
- Research Center for Computational Science, Institute for Molecular Science, Okazaki, Aichi 444-8585, Japan
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13
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Neural functions of bisecting GlcNAc. Glycoconj J 2018; 35:345-351. [DOI: 10.1007/s10719-018-9829-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Revised: 06/01/2018] [Accepted: 06/05/2018] [Indexed: 01/02/2023]
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14
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Hanashima S, Suga A, Yamaguchi Y. Bisecting GlcNAc restricts conformations of branches in model N-glycans with GlcNAc termini. Carbohydr Res 2018; 456:53-60. [PMID: 29274553 DOI: 10.1016/j.carres.2017.12.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 12/10/2017] [Indexed: 01/23/2023]
Abstract
Bisected N-glycans play significant roles in tumor migration and Alzheimer's disease through modulating the action and localization of their carrier proteins. Such biological functions are often discussed in terms of the conformation of the attached N-glycans with or without bisecting GlcNAc. To obtain insights into the effects of bisecting GlcNAc on glycan conformation, a systematic NMR structural analysis was performed on two pairs of synthetic N-glycans, with and without bisecting GlcNAc. The analysis reveals that terminal GlcNAcs and bisecting GlcNAc cooperate to restrict the conformations of both the α1-3 and α1-6 branches of N-glycans. 1H and 13C chemical shift comparisons suggest that bisecting GlcNAc directly modulates local conformation. Unique NOE correlations between core-mannose and the α1-3 branch mannose as well as the 3JC-H constant of the glycoside linkage indicate that bisecting GlcNAc restricts the conformation of the 1-3 branch. The angles of the glycosidic bonds between core-mannose and α1-6 branch mannose derived from 3JC-H and 3JH-H coupling constants show that terminal GlcNAcs restrict the distribution of the ψ angle to 180° and the bisecting GlcNAc increases the distribution of the ω angle +60° in the presence of terminal GlcNAcs. It is feasible that restriction of branch conformations by bisecting GlcNAc has important consequences for protein-glycan interplay and following biological events.
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Affiliation(s)
- Shinya Hanashima
- Structural Glycobiology Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center for Systems Chemical Biology, RIKEN Global Research Cluster, Wako, Saitama, 351-0198, Japan; Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Akitsugu Suga
- Structural Glycobiology Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center for Systems Chemical Biology, RIKEN Global Research Cluster, Wako, Saitama, 351-0198, Japan
| | - Yoshiki Yamaguchi
- Structural Glycobiology Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center for Systems Chemical Biology, RIKEN Global Research Cluster, Wako, Saitama, 351-0198, Japan.
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15
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Turupcu A, Oostenbrink C. Modeling of Oligosaccharides within Glycoproteins from Free-Energy Landscapes. J Chem Inf Model 2017; 57:2222-2236. [PMID: 28816453 PMCID: PMC5615373 DOI: 10.1021/acs.jcim.7b00351] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
In
spite of the abundance of glycoproteins in biological processes,
relatively little three-dimensional structural data is available for
glycan structures. Here, we study the structure and flexibility of
the vast majority of mammalian oligosaccharides appearing in N- and
O-glycosylated proteins using a bottom up approach. We report the
conformational free-energy landscapes of all relevant glycosidic linkages
as obtained from local elevation simulations and subsequent umbrella
sampling. To the best of our knowledge, this represents the first
complete conformational library for the construction of N- and O-glycan
structures. Next, we systematically study the effect of neighboring
residues, by extensively simulating all relevant trisaccharides and
one tetrasaccharide. This allows for an unprecedented comparison of
disaccharide linkages in large oligosaccharides. With a small number
of exceptions, the conformational preferences in the larger structures
are very similar as in the disaccharides. This, finally, allows us
to suggest several efficient approaches to construct complete N- and
O-glycans on glycoproteins, as exemplified on two relevant examples.
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Affiliation(s)
- Aysegül Turupcu
- Institute of Molecular Modeling and Simulation, University of Natural Resources and Life Sciences , Muthgasse 18, 1190 Vienna, Austria
| | - Chris Oostenbrink
- Institute of Molecular Modeling and Simulation, University of Natural Resources and Life Sciences , Muthgasse 18, 1190 Vienna, Austria
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16
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Conformational Heterogeneity of the HIV Envelope Glycan Shield. Sci Rep 2017; 7:4435. [PMID: 28667249 PMCID: PMC5493700 DOI: 10.1038/s41598-017-04532-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 05/16/2017] [Indexed: 01/08/2023] Open
Abstract
To better understand the conformational properties of the glycan shield covering the surface of the HIV gp120/gp41 envelope (Env) trimer, and how the glycan shield impacts the accessibility of the underlying protein surface, we performed enhanced sampling molecular dynamics (MD) simulations of a model glycosylated HIV Env protein and related systems. Our simulation studies revealed a conformationally heterogeneous glycan shield with a network of glycan-glycan interactions more extensive than those observed to date. We found that partial preorganization of the glycans potentially favors binding by established broadly neutralizing antibodies; omission of several specific glycans could increase the accessibility of other glycans or regions of the protein surface to antibody or CD4 receptor binding; the number of glycans that can potentially interact with known antibodies is larger than that observed in experimental studies; and specific glycan conformations can maximize or minimize interactions with individual antibodies. More broadly, the enhanced sampling MD simulations described here provide a valuable tool to guide the engineering of specific Env glycoforms for HIV vaccine design.
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17
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Galvelis R, Re S, Sugita Y. Enhanced Conformational Sampling of N-Glycans in Solution with Replica State Exchange Metadynamics. J Chem Theory Comput 2017; 13:1934-1942. [DOI: 10.1021/acs.jctc.7b00079] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Raimondas Galvelis
- RIKEN Theoretical Molecular Science Laboratory, 2-1 Hirosawa, Wako-shi,
Saitama 351-0198, Japan
| | - Suyong Re
- RIKEN Theoretical Molecular Science Laboratory, 2-1 Hirosawa, Wako-shi,
Saitama 351-0198, Japan
- RIKEN Quantitative Biology Center, Integrated Innovation Building 7F, 6-7-1 minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan
| | - Yuji Sugita
- RIKEN Theoretical Molecular Science Laboratory, 2-1 Hirosawa, Wako-shi,
Saitama 351-0198, Japan
- RIKEN iTHES, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- RIKEN Advanced Institute for Computational Science, Integrated Innovation Building 7F, 6-7-1 minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan
- RIKEN Quantitative Biology Center, Integrated Innovation Building 7F, 6-7-1 minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan
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18
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Kizuka Y. Expression of Neural Glycans and Their Role in Disease. TRENDS GLYCOSCI GLYC 2017. [DOI: 10.4052/tigg.1613.2j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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19
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Kizuka Y. Expression of Neural Glycans and Their Role in Disease. TRENDS GLYCOSCI GLYC 2017. [DOI: 10.4052/tigg.1613.2e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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20
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Carvalho S, Reis CA, Pinho SS. Cadherins Glycans in Cancer: Sweet Players in a Bitter Process. Trends Cancer 2016; 2:519-531. [PMID: 28741480 DOI: 10.1016/j.trecan.2016.08.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 08/01/2016] [Accepted: 08/13/2016] [Indexed: 01/23/2023]
Abstract
Cadherins are key components in tissue morphogenesis and architecture, contributing to the establishment of cohesive cell adhesion. Reduced cellular adhesiveness as a result of cadherin dysfunction is a defining feature of cancer. During tumor development and progression, major changes in the glycan repertoire of cancer cells take place, affecting the stability, trafficking, and cell-adhesion properties of cadherins. Importantly, the different glycoforms of cadherins are promising biomarkers, with potential clinical application to improve the management of patients, and constitute targets for the development of new therapies. This review discusses the most recent insights on the impact of glycan structure on the regulation of cadherin function in cancer, and provides a perspective on how cadherin glycans constitute tumor biomarkers and potential therapeutic targets.
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Affiliation(s)
- Sandra Carvalho
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 4200-135 Porto, Portugal; Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Rua Júlio Amaral de Carvalho 45, 4200-465 Porto, Portugal
| | - Celso A Reis
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 4200-135 Porto, Portugal; Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Rua Júlio Amaral de Carvalho 45, 4200-465 Porto, Portugal; Institute of Biomedical Sciences of Abel Salazar (ICBAS), University of Porto, Rua de Jorge Viterbo Ferreira, 4050-313 Porto, Portugal; Medical Faculty, University of Porto, Alameda Professor Hernâni Monteiro, 4200-319 Porto, Portugal
| | - Salomé S Pinho
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 4200-135 Porto, Portugal; Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Rua Júlio Amaral de Carvalho 45, 4200-465 Porto, Portugal; Medical Faculty, University of Porto, Alameda Professor Hernâni Monteiro, 4200-319 Porto, Portugal.
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21
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Kanjanatanin P, Pichyangkura R, Chunsrivirot S. Replica exchange molecular dynamics simulations reveal the structural and molecular properties of levan-type fructo-oligosaccharides of various chain lengths. BMC Bioinformatics 2016; 17:306. [PMID: 27534934 PMCID: PMC4989353 DOI: 10.1186/s12859-016-1182-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 08/12/2016] [Indexed: 12/17/2022] Open
Abstract
Background Levan and levan-type fructo-oligosaccharides (LFOs) have various potential applications in pharmaceutical and food industries due to their beneficial properties such as their low intrinsic viscosity and high water solubility. Previous studies showed that they exhibited prebiotic effects, anti-inflammatory and anti-tumor activities against Sarcoma-180 tumor cells of human. Despite their various potential applications, the structural and molecular properties of LFOs of various chain lengths are not well understood. Results We employed the replica-exchange molecular dynamics simulations method (REMD) in AMBER14 to elucidate structural and molecular properties of LFOs with chain lengths of 5 (LFO5), 10 (LFO10) and 15 (LFO15) residues in two models of generalized Born implicit solvent (GBHCT and GBOBC1). For LFO10 and LFO15, four distinct conformations (helix-like, partial helix, zig-zag and random structures) were characterized by their upper-middle and lower-middle torsions. For LFO5, two distinct conformations (partial helix and random structures) were characterized by their middle torsion and molecular angle of residues 1, 3 and 5. To determine hydrogen bonds important for the formation of helix-like structures of LFO10 and LFO15, occurrence frequencies of hydrogen bonds were analyzed, and the O6(i)--H3O(i+1) hydrogen bond was found with the highest frequency, suggesting its importance in helix formation. Among three dihedral angles between two fructosyl units [ϕ (O5’-C2’-O6-C6), ψ (C2’-O6-C6-C5) and ω (O6-C6-C5-C4)], dihedral angle distributions showed that ω was the most flexible dihedral angle and probably responsible for conformational differences of LFOs. Conclusions Our study provides important insights into the structural and molecular properties of LFOs, which tend to form helical structures as the chain length increases from 5 to 15 residues. This information could be beneficial for the selection of LFOs with appropriate lengths and properties for pharmaceutical and biological applications. Electronic supplementary material The online version of this article (doi:10.1186/s12859-016-1182-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Pongsakorn Kanjanatanin
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, 254 Phaya Thai road, Pathumwan, Bangkok, 10330, Thailand.,Structural and Computational Biology Research Group, Department of Biochemistry, Faculty of Science, Chulalongkorn University, 254 Phaya Thai road, Pathumwan, Bangkok, 10330, Thailand
| | - Rath Pichyangkura
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, 254 Phaya Thai road, Pathumwan, Bangkok, 10330, Thailand
| | - Surasak Chunsrivirot
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, 254 Phaya Thai road, Pathumwan, Bangkok, 10330, Thailand. .,Structural and Computational Biology Research Group, Department of Biochemistry, Faculty of Science, Chulalongkorn University, 254 Phaya Thai road, Pathumwan, Bangkok, 10330, Thailand.
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22
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Yang M, Angles d’Ortoli T, Säwén E, Jana M, Widmalm G, MacKerell AD. Delineating the conformational flexibility of trisaccharides from NMR spectroscopy experiments and computer simulations. Phys Chem Chem Phys 2016; 18:18776-94. [PMID: 27346493 PMCID: PMC4945446 DOI: 10.1039/c6cp02970a] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The conformation of saccharides in solution is challenging to characterize in the context of a single well-defined three-dimensional structure. Instead, they are better represented by an ensemble of conformations associated with their structural diversity and flexibility. In this study, we delineate the conformational heterogeneity of five trisaccharides via a combination of experimental and computational techniques. Experimental NMR measurements target conformationally sensitive parameters, including J couplings and effective distances around the glycosidic linkages, while the computational simulations apply the well-calibrated additive CHARMM carbohydrate force field in combination with efficient enhanced sampling molecular dynamics simulation methods. Analysis of conformational heterogeneity is performed based on sampling of discreet states as defined by dihedral angles, on root-mean-square differences of Cartesian coordinates and on the extent of volume sampled. Conformational clustering, based on the glycosidic linkage dihedral angles, shows that accounting for the full range of sampled conformations is required to reproduce the experimental data, emphasizing the utility of the molecular simulations in obtaining an atomic detailed description of the conformational properties of the saccharides. Results show the presence of differential conformational preferences as a function of primary sequence and glycosidic linkage types. Significant differences in conformational ensembles associated with the anomeric configuration of a single glycosidic linkage reinforce the impact of such changes on the conformational properties of carbohydrates. The present structural insights of the studied trisaccharides represent a foundation for understanding the range of conformations adopted in larger oligosaccharides and how these molecules encode their conformational heterogeneity into the monosaccharide sequence.
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Affiliation(s)
- Mingjun Yang
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Maryland 21201
| | - Thibault Angles d’Ortoli
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, S-106 91 Stockholm, Sweden
| | - Elin Säwén
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, S-106 91 Stockholm, Sweden
| | - Madhurima Jana
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Maryland 21201
- Department of Chemistry, National Institute of Technology Rourkela, Odisha, India 769008
| | - Göran Widmalm
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, S-106 91 Stockholm, Sweden
| | - Alexander D. MacKerell
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Maryland 21201
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23
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Yang M, Huang J, MacKerell AD. Enhanced conformational sampling using replica exchange with concurrent solute scaling and hamiltonian biasing realized in one dimension. J Chem Theory Comput 2016; 11:2855-67. [PMID: 26082676 PMCID: PMC4463548 DOI: 10.1021/acs.jctc.5b00243] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Indexed: 12/17/2022]
Abstract
![]()
Replica exchange (REX) is a powerful
computational tool for overcoming
the quasi-ergodic sampling problem of complex molecular systems. Recently,
several multidimensional extensions of this method have been developed
to realize exchanges in both temperature and biasing potential space
or the use of multiple biasing potentials to improve sampling efficiency.
However, increased computational cost due to the multidimensionality
of exchanges becomes challenging for use on complex systems under
explicit solvent conditions. In this study, we develop a one-dimensional
(1D) REX algorithm to concurrently combine the advantages of overall
enhanced sampling from Hamiltonian solute scaling and the specific
enhancement of collective variables using Hamiltonian biasing potentials.
In the present Hamiltonian replica exchange method, termed HREST-BP,
Hamiltonian solute scaling is applied to the solute subsystem, and
its interactions with the environment to enhance overall conformational
transitions and biasing potentials are added along selected collective
variables associated with specific conformational transitions, thereby
balancing the sampling of different hierarchical degrees of freedom.
The two enhanced sampling approaches are implemented concurrently
allowing for the use of a small number of replicas (e.g., 6 to 8)
in 1D, thus greatly reducing the computational cost in complex system
simulations. The present method is applied to conformational sampling
of two nitrogen-linked glycans (N-glycans) found
on the HIV gp120 envelope protein. Considering the general importance
of the conformational sampling problem, HREST-BP represents an efficient
procedure for the study of complex saccharides, and, more generally,
the method is anticipated to be of general utility for the conformational
sampling in a wide range of macromolecular systems.
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Affiliation(s)
- Mingjun Yang
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Maryland 21201, United States
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24
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Yang M, MacKerell AD. Conformational sampling of oligosaccharides using Hamiltonian replica exchange with two-dimensional dihedral biasing potentials and the weighted histogram analysis method (WHAM). J Chem Theory Comput 2016; 11:788-99. [PMID: 25705140 DOI: 10.1021/ct500993h] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Oligosaccharides and polysaccharides exert numerous functional roles in biology through their structural diversity and conformational properties. To investigate their conformational properties using computational methods, Hamiltonian replica exchange (H-REX) combined with two-dimensional grid-based correction maps as biasing potentials (bpCMAP) significantly improves the sampling efficiency about glycosidic linkages. In the current study, we extend the application of H-REX with bpCMAP to complex saccharides and establish systematic procedures for bpCMAP construction, determination of replica distribution, and data analysis. Our main findings are that (1) the bpCMAP for each type of glycosidic linkage can be constructed from the corresponding disaccharide using gas-phase umbrella sampling simulations, (2) the replica distribution can be conveniently determined following the exact definition of the average acceptance ratio based on the assigned distribution of biasing potentials, and (3) the extracted free energy surface (or potential of mean force (PMF)) can be improved using the weighted histogram analysis method (WHAM) allowing for the inclusion of data from the excited state replicas in the calculated probability distribution. The method is applied to a branched N-glycan found on the HIV gp120 protein, and a linear N-glycan. Considering the general importance of N-glycans and the wide appreciation of the sampling problem, the present method represents an efficient procedure for the conformational sampling of complex oligo- and polysaccharides under explicit solvent conditions. More generally, the use of WHAM is anticipated to be of general utility for the calculation of PMFs from H-REX simulations in a wide range of macromolecular systems.
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Affiliation(s)
- Mingjun Yang
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Maryland 21201, United States
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25
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Enzymes for N-Glycan Branching and Their Genetic and Nongenetic Regulation in Cancer. Biomolecules 2016; 6:biom6020025. [PMID: 27136596 PMCID: PMC4919920 DOI: 10.3390/biom6020025] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 04/15/2016] [Accepted: 04/21/2016] [Indexed: 02/07/2023] Open
Abstract
N-glycan, a fundamental and versatile protein modification in mammals, plays critical roles in various physiological and pathological events including cancer progression. The formation of N-glycan branches catalyzed by specific N-acetylglucosaminyltransferases [GnT-III, GnT-IVs, GnT-V, GnT-IX (Vb)] and a fucosyltransferase, Fut8, provides functionally diverse N-glycosylated proteins. Aberrations of these branches are often found in cancer cells and are profoundly involved in cancer growth, invasion and metastasis. In this review, we focus on the GlcNAc and fucose branches of N-glycans and describe how their expression is dysregulated in cancer by genetic and nongenetic mechanisms including epigenetics and nucleotide sugar metabolisms. We also survey the roles that these N-glycans play in cancer progression and therapeutics. Finally, we discuss possible applications of our knowledge on basic glycobiology to the development of medicine and biomarkers for cancer therapy.
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26
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Nagae M, Kanagawa M, Morita-Matsumoto K, Hanashima S, Kizuka Y, Taniguchi N, Yamaguchi Y. Atomic visualization of a flipped-back conformation of bisected glycans bound to specific lectins. Sci Rep 2016; 6:22973. [PMID: 26971576 PMCID: PMC4789653 DOI: 10.1038/srep22973] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 02/23/2016] [Indexed: 11/09/2022] Open
Abstract
Glycans normally exist as a dynamic equilibrium of several conformations. A fundamental question concerns how such molecules bind lectins despite disadvantageous entropic loss upon binding. Bisected glycan, a glycan possessing bisecting N-acetylglucosamine (GlcNAc), is potentially a good model for investigating conformational dynamics and glycan-lectin interactions, owing to the unique ability of this sugar residue to alter conformer populations and thus modulate the biological activities. Here we analyzed bisected glycan in complex with two unrelated lectins, Calsepa and PHA-E. The crystal structures of the two complexes show a conspicuous flipped back glycan structure (designated 'back-fold' conformation), and solution NMR analysis also provides evidence of 'back-fold' glycan structure. Indeed, statistical conformational analysis of available bisected and non-bisected glycan structures suggests that bisecting GlcNAc restricts the conformations of branched structures. Restriction of glycan flexibility by certain sugar residues may be more common than previously thought and impinges on the mechanism of glycoform-dependent biological functions.
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Affiliation(s)
- Masamichi Nagae
- Structural Glycobiology Team, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Mayumi Kanagawa
- Structural Glycobiology Team, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | | | - Shinya Hanashima
- Department of Chemistry, Osaka University, Machikaneyama, Toyonaka, Osaka 560-0043, Japan
| | - Yasuhiko Kizuka
- Disease Glycomics Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center, RIKEN Global Research Cluster, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Naoyuki Taniguchi
- Disease Glycomics Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center, RIKEN Global Research Cluster, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Yoshiki Yamaguchi
- Structural Glycobiology Team, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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27
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Bisecting GlcNAc modification stabilizes BACE1 protein under oxidative stress conditions. Biochem J 2015; 473:21-30. [DOI: 10.1042/bj20150607] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 10/14/2015] [Indexed: 12/29/2022]
Abstract
BACE1 is a protease essential for amyloid-β production in Alzheimer's disease. We report that bisecting GlcNAc modification on BACE1 stabilizes BACE1 protein under oxidative stress conditions. This suggests that bisecting GlcNAc is a therapeutic target for Alzheimer's disease.
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28
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Jo S, Qi Y, Im W. Preferred conformations of N-glycan core pentasaccharide in solution and in glycoproteins. Glycobiology 2015; 26:19-29. [PMID: 26405106 DOI: 10.1093/glycob/cwv083] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 09/14/2015] [Indexed: 11/13/2022] Open
Abstract
N-linked glycans are on protein surfaces and have direct and water/ion-mediated interactions with surrounding amino acids. Such contacts could restrict their conformational freedom compared to the same glycans free in solution. In this work, we have examined the conformational freedom of the N-glycan core pentasaccharide moiety in solution using standard molecular dynamics (MD) simulations as well as temperature replica-exchange MD simulations. Both simulations yield the comparable conformational variability of the pentasaccharide in solution, indicating the convergence of both simulations. The glycoprotein crystal structures are analyzed to compare the conformational freedom of the N-glycan on the protein surface with the simulation result. Surprisingly, the pentasaccharide free in solution shows more restricted conformational variability than the N-glycan on the protein surface. The interactions between the carbohydrate and the protein side chain appear to be responsible for the increased conformational diversity of the N-glycan on the protein surface. Finally, the transfer entropy analysis of the simulation trajectory also reveals an unexpected causality relationship between intramolecular hydrogen bonds and the conformational states in that the hydrogen bonds play a role in maintaining the conformational states rather than driving the change in glycosidic torsional states.
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Affiliation(s)
- Sunhwan Jo
- Leadership Computing Center, Argonne National Laboratory, 9700 Cass Ave Bldg. 240, Argonne, IL 60439, USA
| | - Yifei Qi
- Department of Molecular Biosciences and Center for Computational Biology, The University of Kansas, 2030 Becker Drive, Lawrence, KS 66047, USA
| | - Wonpil Im
- Department of Molecular Biosciences and Center for Computational Biology, The University of Kansas, 2030 Becker Drive, Lawrence, KS 66047, USA
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29
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Frank M, Collins PM, Peak IR, Grice ID, Wilson JC. An Unusual Carbohydrate Conformation is Evident in Moraxella catarrhalis Oligosaccharides. Molecules 2015; 20:14234-53. [PMID: 26251889 PMCID: PMC6332130 DOI: 10.3390/molecules200814234] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2015] [Revised: 07/24/2015] [Accepted: 07/27/2015] [Indexed: 01/28/2023] Open
Abstract
Oligosaccharide structures derived from the lipooligosaccharide of M. catarrhalis show that the highly branched glucose-rich inner core of the oligosaccharide has an altered conformation compared to the most truncated tetra-glucose-Kdo lgt1/4Δ oligosaccharide structure. Addition of one residue each to the (1-4) and (1-6) chains to give the lgt2Δ oligosaccharide is the minimum requirement for this conformational change to occur. Extensive molecular modeling and NMR investigations have shown that the (1-3), (1-4), and (1-6) glycosidic linkages from the central α-d-Glcp have significantly altered conformational preferences between the two structures. For the lgt1/4Δ oligosaccharide the (1-3) and (1-4) linkage populates predominantly the syn minimum on the conformational free energy map and for the (1-6) linkage conformational flexibility is observed, which is supported by 1H-NMR T1 measurements. For the lgt2Δ oligosaccharide the unusual “(1-4)anti-ψ(1-6)gg” conformation, which could be confirmed by long-range NOE signals, is a dominant conformation in which the oligosaccharide is very compact with the terminal α-d-GlcNAc residue folding back towards the center of the molecule leading to an extensive intra-molecular hydrophobic interaction between the terminal residues. Comparing effective H-H distances, which were calculated for conformational sub-ensembles, with the NOE distances revealed that typically multiple conformations could be present without significantly violating the measured NOE restraints. For lgt2Δ the presence of more than one conformation is supported by the NOE data.
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Affiliation(s)
- Martin Frank
- Biognos AB, Generatorsgatan 1, 41705 Gothenburg, Sweden.
| | - Patrick M Collins
- Institute for Glycomics, Gold Coast Campus, Griffith University, 4222 Queensland, Australia.
| | - Ian R Peak
- Institute for Glycomics and School of Medical Science, Gold Coast Campus, Griffith University, 4222 Queensland, Australia.
| | - I Darren Grice
- Institute for Glycomics and School of Medical Science, Gold Coast Campus, Griffith University, 4222 Queensland, Australia.
| | - Jennifer C Wilson
- Menzies Health Institute and School of Medical Science, Gold Coast Campus, Griffith University, 4222 Queensland, Australia.
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30
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Kern NR, Lee HS, Wu EL, Park S, Vanommeslaeghe K, MacKerell AD, Klauda JB, Jo S, Im W. Lipid-linked oligosaccharides in membranes sample conformations that facilitate binding to oligosaccharyltransferase. Biophys J 2015; 107:1885-1895. [PMID: 25418169 DOI: 10.1016/j.bpj.2014.09.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 09/05/2014] [Accepted: 09/09/2014] [Indexed: 01/21/2023] Open
Abstract
Lipid-linked oligosaccharides (LLOs) are the substrates of oligosaccharyltransferase (OST), the enzyme that catalyzes the en bloc transfer of the oligosaccharide onto the acceptor asparagine of nascent proteins during the process of N-glycosylation. To explore LLOs' preferred location, orientation, structure, and dynamics in membrane bilayers of three different lipid types (dilauroylphosphatidylcholine, dimyristoylphosphatidylcholine, and dioleoylphosphatidylcholine), we have modeled and simulated both eukaryotic (Glc3-Man9-GlcNAc2-PP-Dolichol) and bacterial (Glc1-GalNAc5-Bac1-PP-Undecaprenol) LLOs, which are composed of an isoprenoid moiety and an oligosaccharide, linked by pyrophosphate. The simulations show no strong impact of different bilayer hydrophobic thicknesses on the overall orientation, structure, and dynamics of the isoprenoid moiety and the oligosaccharide. The pyrophosphate group stays in the bilayer head group region. The isoprenoid moiety shows high flexibility inside the bilayer hydrophobic core, suggesting its potential role as a tentacle to search for OST. The oligosaccharide conformation and dynamics are similar to those in solution, but there are preferred interactions between the oligosaccharide and the bilayer interface, which leads to LLO sugar orientations parallel to the bilayer surface. Molecular docking of the bacterial LLO to a bacterial OST suggests that such orientations can enhance binding of LLOs to OST.
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Affiliation(s)
- Nathan R Kern
- Department of Molecular Biosciences and Center for Bioinformatics, University of Kansas, Lawrence, Kansas
| | - Hui Sun Lee
- Department of Molecular Biosciences and Center for Bioinformatics, University of Kansas, Lawrence, Kansas
| | - Emilia L Wu
- Department of Molecular Biosciences and Center for Bioinformatics, University of Kansas, Lawrence, Kansas
| | - Soohyung Park
- Department of Molecular Biosciences and Center for Bioinformatics, University of Kansas, Lawrence, Kansas
| | - Kenno Vanommeslaeghe
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Maryland
| | - Alexander D MacKerell
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Maryland
| | - Jeffery B Klauda
- Department of Chemical and Biomolecular Engineering and Biophysics Program, University of Maryland, College Park, Maryland
| | - Sunhwan Jo
- Department of Molecular Biosciences and Center for Bioinformatics, University of Kansas, Lawrence, Kansas
| | - Wonpil Im
- Department of Molecular Biosciences and Center for Bioinformatics, University of Kansas, Lawrence, Kansas.
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Canales A, Mallagaray A, Pérez-Castells J, Boos I, Unverzagt C, André S, Gabius HJ, Cañada FJ, Jiménez-Barbero J. Breaking Pseudo-Symmetry in Multiantennary Complex N-Glycans Using Lanthanide-Binding Tags and NMR Pseudo-Contact Shifts. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201307845] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Canales A, Mallagaray A, Pérez-Castells J, Boos I, Unverzagt C, André S, Gabius HJ, Cañada FJ, Jiménez-Barbero J. Breaking Pseudo-Symmetry in Multiantennary Complex N-Glycans Using Lanthanide-Binding Tags and NMR Pseudo-Contact Shifts. Angew Chem Int Ed Engl 2013; 52:13789-93. [DOI: 10.1002/anie.201307845] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Indexed: 01/24/2023]
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Nagae M, Yamanaka K, Hanashima S, Ikeda A, Morita-Matsumoto K, Satoh T, Matsumoto N, Yamamoto K, Yamaguchi Y. Recognition of bisecting N-acetylglucosamine: structural basis for asymmetric interaction with the mouse lectin dendritic cell inhibitory receptor 2. J Biol Chem 2013; 288:33598-33610. [PMID: 24108122 DOI: 10.1074/jbc.m113.513572] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Dendritic cell inhibitory receptor 2 (DCIR2) is a C-type lectin expressed on classical dendritic cells. We recently identified the unique ligand specificity of mouse DCIR2 (mDCIR2) toward biantennary complex-type glycans containing bisecting N-acetylglucosamine (GlcNAc). Here, we report the crystal structures of the mDCIR2 carbohydrate recognition domain in unliganded form as well as in complex with an agalactosylated complex-type N-glycan unit carrying a bisecting GlcNAc residue. Bisecting GlcNAc and the α1-3 branch of the biantennary oligosaccharide asymmetrically interact with canonical and non-canonical mDCIR2 residues. Ligand-protein interactions occur directly through mDCIR2-characteristic amino acid residues as well as via a calcium ion and water molecule. Our structural and biochemical data elucidate for the first time the unique binding mode of mDCIR2 for bisecting GlcNAc-containing glycans, a mode that contrasts sharply with that of other immune C-type lectin receptors such as DC-SIGN.
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Affiliation(s)
- Masamichi Nagae
- Structural Glycobiology Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center, RIKEN Global Research Cluster, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Kousuke Yamanaka
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba 277-8562, Japan
| | - Shinya Hanashima
- Structural Glycobiology Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center, RIKEN Global Research Cluster, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Akemi Ikeda
- Structural Glycobiology Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center, RIKEN Global Research Cluster, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Kana Morita-Matsumoto
- Structural Glycobiology Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center, RIKEN Global Research Cluster, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Tadashi Satoh
- Structural Glycobiology Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center, RIKEN Global Research Cluster, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Naoki Matsumoto
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba 277-8562, Japan
| | - Kazuo Yamamoto
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba 277-8562, Japan
| | - Yoshiki Yamaguchi
- Structural Glycobiology Team, Systems Glycobiology Research Group, RIKEN-Max Planck Joint Research Center, RIKEN Global Research Cluster, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
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Jo S, Lee HS, Skolnick J, Im W. Restricted N-glycan conformational space in the PDB and its implication in glycan structure modeling. PLoS Comput Biol 2013; 9:e1002946. [PMID: 23516343 PMCID: PMC3597548 DOI: 10.1371/journal.pcbi.1002946] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Accepted: 01/10/2013] [Indexed: 11/29/2022] Open
Abstract
Understanding glycan structure and dynamics is central to understanding protein-carbohydrate recognition and its role in protein-protein interactions. Given the difficulties in obtaining the glycan's crystal structure in glycoconjugates due to its flexibility and heterogeneity, computational modeling could play an important role in providing glycosylated protein structure models. To address if glycan structures available in the PDB can be used as templates or fragments for glycan modeling, we present a survey of the N-glycan structures of 35 different sequences in the PDB. Our statistical analysis shows that the N-glycan structures found on homologous glycoproteins are significantly conserved compared to the random background, suggesting that N-glycan chains can be confidently modeled with template glycan structures whose parent glycoproteins share sequence similarity. On the other hand, N-glycan structures found on non-homologous glycoproteins do not show significant global structural similarity. Nonetheless, the internal substructures of these N-glycans, particularly, the substructures that are closer to the protein, show significantly similar structures, suggesting that such substructures can be used as fragments in glycan modeling. Increased interactions with protein might be responsible for the restricted conformational space of N-glycan chains. Our results suggest that structure prediction/modeling of N-glycans of glycoconjugates using structure database could be effective and different modeling approaches would be needed depending on the availability of template structures. An N-glycan is a carbohydrate chain covalently linked to the side chain of asparagine. Due to the flexibility of carbohydrate chains, it is believed that the N-glycan chains would not have a well-defined structure. However, our survey of N-glycan structures in the PDB shows that the N-glycan structures found on the surfaces of homologous glycoproteins are significantly conserved. This suggests that the interaction between the carbohydrate and the protein structure around the glycan chain plays an important role in determining the N-glycan structure. While the global N-glycan structures found on the surfaces of non-homologous glycoproteins are not conserved, the conformations of the carbohydrate residues that are closer to the protein appear to be more conserved. Our analysis highlights the applicability of template-based approaches used in protein structure prediction to structure prediction and modeling of N-glycans of glycoproteins.
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Affiliation(s)
- Sunhwan Jo
- Department of Molecular Biosciences and Center for Bioinformatics, The University of Kansas, Lawrence, Kansas, United States of America
| | - Hui Sun Lee
- Department of Molecular Biosciences and Center for Bioinformatics, The University of Kansas, Lawrence, Kansas, United States of America
| | - Jeffrey Skolnick
- Center for the Study of Systems Biology, School of Biology, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Wonpil Im
- Department of Molecular Biosciences and Center for Bioinformatics, The University of Kansas, Lawrence, Kansas, United States of America
- * E-mail:
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Re S, Nishima W, Miyashita N, Sugita Y. Conformational flexibility of N-glycans in solution studied by REMD simulations. Biophys Rev 2012; 4:179-187. [PMID: 28510079 DOI: 10.1007/s12551-012-0090-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Accepted: 06/21/2012] [Indexed: 01/09/2023] Open
Abstract
Protein-glycan recognition regulates a wide range of biological and pathogenic processes. Conformational diversity of glycans in solution is apparently incompatible with specific binding to their receptor proteins. One possibility is that among the different conformational states of a glycan, only one conformer is utilized for specific binding to a protein. However, the labile nature of glycans makes characterizing their conformational states a challenging issue. All-atom molecular dynamics (MD) simulations provide the atomic details of glycan structures in solution, but fairly extensive sampling is required for simulating the transitions between rotameric states. This difficulty limits application of conventional MD simulations to small fragments like di- and tri-saccharides. Replica-exchange molecular dynamics (REMD) simulation, with extensive sampling of structures in solution, provides a valuable way to identify a family of glycan conformers. This article reviews recent REMD simulations of glycans carried out by us or other research groups and provides new insights into the conformational equilibria of N-glycans and their alteration by chemical modification. We also emphasize the importance of statistical averaging over the multiple conformers of glycans for comparing simulation results with experimental observables. The results support the concept of "conformer selection" in protein-glycan recognition.
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Affiliation(s)
- Suyong Re
- RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Wataru Nishima
- RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Naoyuki Miyashita
- RIKEN Quantitative Biology Center, IMDA 6F, 1-6-5 Minatojimaminamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan
| | - Yuji Sugita
- RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan. .,RIKEN Quantitative Biology Center, IMDA 6F, 1-6-5 Minatojimaminamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan. .,RIKEN Advanced Institute for Computational Science, 7-1-26 Minatojimaminamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan.
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Nishima W, Miyashita N, Yamaguchi Y, Sugita Y, Re S. Effect of bisecting GlcNAc and core fucosylation on conformational properties of biantennary complex-type N-glycans in solution. J Phys Chem B 2012; 116:8504-12. [PMID: 22530754 DOI: 10.1021/jp212550z] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The introduction of bisecting GlcNAc and core fucosylation in N-glycans is essential for fine functional regulation of glycoproteins. In this paper, the effect of these modifications on the conformational properties of N-glycans is examined at the atomic level by performing replica-exchange molecular dynamics (REMD) simulations. We simulate four biantennary complex-type N-glycans, namely, unmodified, two single-substituted with either bisecting GlcNAc or core fucose, and disubstituted forms. By using REMD as an enhanced sampling technique, five distinct conformers in solution, each of which is characterized by its local orientation of the Manα1-6Man glycosidic linkage, are observed for all four N-glycans. The chemical modifications significantly change their conformational equilibria. The number of major conformers is reduced from five to two and from five to four upon the introduction of bisecting GlcNAc and core fucosylation, respectively. The population change is attributed to specific inter-residue hydrogen bonds, including water-mediated ones. The experimental NMR data, including nuclear Overhauser enhancement and scalar J-coupling constants, are well reproduced taking the multiple conformers into account. Our structural model supports the concept of "conformer selection", which emphasizes the conformational flexibility of N-glycans in protein-glycan interactions.
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Affiliation(s)
- Wataru Nishima
- RIKEN Advanced Science Institute, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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