1
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Mogas-Soldevila L, Duro-Royo J, Lizardo D, Hollyer GG, Settens CM, Cox JM, Overvelde JTB, DiMasi E, Bertoldi K, Weaver JC, Oxman N. Driving macro-scale transformations in three-dimensional-printed biopolymers through controlled induction of molecular anisotropy at the nanoscale. Interface Focus 2024; 14:20230077. [PMID: 39081628 PMCID: PMC11285838 DOI: 10.1098/rsfs.2023.0077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Revised: 03/05/2024] [Accepted: 05/07/2024] [Indexed: 08/02/2024] Open
Abstract
Motivated by the need to harness the properties of renewable and biodegradable polymers for the design and manufacturing of multi-scale structures with complex geometries, we have employed our additive manufacturing platform that leverages molecular self-assembly for the production of metre-scale structures characterized by complex geometries and heterogeneous material composition. As a precursor material, we used chitosan, a chemically modified form of chitin, an abundant and sustainable structural polysaccharide. We demonstrate the ability to control concentration-dependent crystallization as well as the induction of the preferred orientation of the polymer chains through the combination of extrusion-based robotic fabrication and directional toolpathing. Anisotropy is demonstrated and assessed through high-resolution micro-X-ray diffraction in conjunction with finite element simulations. Using this approach, we can leverage controlled and user-defined small-scale propagation of residual stresses to induce large-scale folding of the resulting structures.
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Affiliation(s)
- Laia Mogas-Soldevila
- DumoLab Research, University of Pennsylvania, Philadelphia, PA19104, USA
- Mediated Matter Group, Massachusetts Institute of Technology, Cambridge, MA02142, USA
| | - Jorge Duro-Royo
- Mediated Matter Group, Massachusetts Institute of Technology, Cambridge, MA02142, USA
| | - Daniel Lizardo
- Mediated Matter Group, Massachusetts Institute of Technology, Cambridge, MA02142, USA
| | - George G. Hollyer
- DumoLab Research, University of Pennsylvania, Philadelphia, PA19104, USA
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA19104, USA
| | - Charles M. Settens
- MIT.nano, Massachusetts Institute of Technology, Cambridge, MA02139, USA
| | - Jordan M. Cox
- MIT.nano, Massachusetts Institute of Technology, Cambridge, MA02139, USA
| | | | - Elaine DiMasi
- Lawrence Berkeley National Laboratory, Berkeley, CA94720, USA
| | - Katia Bertoldi
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA02138, USA
| | - James C. Weaver
- MIT.nano, Massachusetts Institute of Technology, Cambridge, MA02139, USA
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA02215, USA
| | - Neri Oxman
- Mediated Matter Group, Massachusetts Institute of Technology, Cambridge, MA02142, USA
- Oxman, New York, NY10019, USA
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2
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Nouri S, Boudet J, Dreher-Teo H, Allain FHT, Glockshuber R, Salmon L, Giese C. Elongated Bacterial Pili as a Versatile Alignment Medium for NMR Spectroscopy. Angew Chem Int Ed Engl 2023; 62:e202305120. [PMID: 37248171 DOI: 10.1002/anie.202305120] [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: 04/11/2023] [Revised: 05/25/2023] [Accepted: 05/26/2023] [Indexed: 05/31/2023]
Abstract
In NMR spectroscopy, residual dipolar couplings (RDCs) have emerged as one of the most exquisite probes of biological structure and dynamics. The measurement of RDCs relies on the partial alignment of the molecule of interest, for example by using a liquid crystal as a solvent. Here, we establish bacterial type 1 pili as an alternative liquid-crystalline alignment medium for the measurement of RDCs. To achieve alignment at pilus concentrations that allow for efficient NMR sample preparation, we elongated wild-type pili by recombinant overproduction of the main structural pilus subunit. Building on the extraordinary stability of type 1 pili against spontaneous dissociation and unfolding, we show that the medium is compatible with challenging experimental conditions such as high temperature, the presence of detergents, organic solvents or very acidic pH, setting it apart from most established alignment media. Using human ubiquitin, HIV-1 TAR RNA and camphor as spectroscopic probes, we demonstrate the applicability of the medium for the determination of RDCs of proteins, nucleic acids and small molecules. Our results show that type 1 pili represent a very useful alternative to existing alignment media and may readily assist the characterization of molecular structure and dynamics by NMR.
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Affiliation(s)
- Sirine Nouri
- Centre de RMN à Très Hauts Champs, CNRS, ENSL, UCBL, Université de Lyon, 5 rue de la Doua, 69100, Villeurbanne, France
| | - Julien Boudet
- Institute of Molecular Biology and Biophysics, ETH Zurich, Otto-Stern-Weg 5, 8093, Zürich, Switzerland
| | - Hiang Dreher-Teo
- Institute of Molecular Biology and Biophysics, ETH Zurich, Otto-Stern-Weg 5, 8093, Zürich, Switzerland
| | - Frédéric H-T Allain
- Institute of Molecular Biology and Biophysics, ETH Zurich, Otto-Stern-Weg 5, 8093, Zürich, Switzerland
- Institute of Biochemistry, ETH Zurich, Otto-Stern-Weg 3, 8093, Zürich, Switzerland
| | - Rudi Glockshuber
- Institute of Molecular Biology and Biophysics, ETH Zurich, Otto-Stern-Weg 5, 8093, Zürich, Switzerland
| | - Loïc Salmon
- Centre de RMN à Très Hauts Champs, CNRS, ENSL, UCBL, Université de Lyon, 5 rue de la Doua, 69100, Villeurbanne, France
- Institute of Molecular Biology and Biophysics, ETH Zurich, Otto-Stern-Weg 5, 8093, Zürich, Switzerland
| | - Christoph Giese
- Institute of Molecular Biology and Biophysics, ETH Zurich, Otto-Stern-Weg 5, 8093, Zürich, Switzerland
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3
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Sannapureddi RKR, Mohanty MK, Salmon L, Sathyamoorthy B. Conformational Plasticity of Parallel G-Quadruplex─Implications on Duplex-Quadruplex Motifs. J Am Chem Soc 2023. [PMID: 37428641 DOI: 10.1021/jacs.3c03218] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/12/2023]
Abstract
DNA G-quadruplexes are essential motifs in molecular biology performing a wide range of functions enabled by their unique and diverse structures. In this study, we focus on the conformational plasticity of the most abundant and biologically relevant parallel G-quadruplex topology. A multipronged approach of structure survey, solution-state NMR spectroscopy, and molecular dynamics simulations unravels subtle yet essential features of the parallel G-quadruplex topology. Stark differences in flexibility are observed for the nucleotides depending upon their positioning in the tetrad planes that are intricately correlated with the conformational sampling of the propeller loop. Importantly, the terminal nucleotides in the 5'-end versus the 3'-end of the parallel quadruplex display differential dynamics that manifests their ability to accommodate a duplex on either end of the G-quadruplex. The conformational plasticity characterized in this study provides essential cues toward biomolecular processes such as small molecular binding, intermolecular quadruplex stacking, and implications on how a duplex influences the structure of a neighboring quadruplex.
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Affiliation(s)
| | - Manish Kumar Mohanty
- Department of Chemistry, Indian Institute of Science Education and Research, Bhopal 462066, India
| | - Loïc Salmon
- Centre de RMN à Très Hauts Champs, UMR 5082 (CNRS, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon 1), University of Lyon, Villeurbanne 69100, France
| | - Bharathwaj Sathyamoorthy
- Department of Chemistry, Indian Institute of Science Education and Research, Bhopal 462066, India
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4
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Yang J, Jiang S, Zhu S, Ren W, Liang H, Li B, Li J. Konjac glucomannan/xanthan gum/sodium alginate composite hydrogel simulates fascial tissue by pre-stretching and moisture regulation. Int J Biol Macromol 2023; 239:124253. [PMID: 37001782 DOI: 10.1016/j.ijbiomac.2023.124253] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 03/10/2023] [Accepted: 03/27/2023] [Indexed: 03/31/2023]
Abstract
Improving the mechanical strength and creating an anisotropic structure of edible macromolecular hydrogels is crucial to accurately simulate the texture of connective tissues. In this study, konjac glucomannan (KGM), xanthan gum (XG), and sodium alginate (SA) were used to construct hydrogels, and the effects of different pre-stretching degrees and moisture control on the composite gels were investigated. The results of the mechanical property tests and microstructure tests indicate that pre-stretching and moisture control can significantly enhance the strength of the gels and induce anisotropic structures. In addition, the feasibility of the composite gel structure in simulating brisket fascia was investigated, and it was concluded that 1.5 × -DR samples were most suitable for simulating connective tissue. This study provides compelling evidence for the potential of macromolecular hydrogels in simulating connective tissue and provides theoretical guidance for regulating gel texture.
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5
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Farley KA, Koos MRM, Che Y, Horst R, Limberakis C, Bellenger J, Lira R, Gil-Silva LF, Gil RR. Cross-Linked Poly-4-Acrylomorpholine: A Flexible and Reversibly Compressible Aligning Gel for Anisotropic NMR Analysis of Peptides and Small Molecules in Water. Angew Chem Int Ed Engl 2021; 60:26314-26319. [PMID: 34609778 DOI: 10.1002/anie.202106794] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Indexed: 11/07/2022]
Abstract
Determination of the solution conformation of both small organic molecules and peptides in water remains a substantial hurdle in using NMR solution conformations to guide drug design due to the lack of easy to use alignment media. Herein we report the design of a flexible compressible chemically cross-linked poly-4-acrylomorpholine gel that can be used for the alignment of both small molecules and cyclic peptides in water. To test the new gel, residual dipolar couplings (RDCs) and J-coupling constants were used in the configurational analysis of strychnine hydrochloride, a molecule that has been studied extensively in organic solvents as well as a small cyclic peptide that is known to form an α-helix in water. The conformational ensembles for each molecule with the best fit to the data are reported. Identification of minor conformers in water that cannot easily be determined by conventional NOE measurements will facilitate the use of RDC experiments in structure-based drug design.
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Affiliation(s)
- Kathleen A Farley
- Medicinal Sciences, Pfizer, Eastern Point Road, Groton, CT, 06340, USA
| | - Martin R M Koos
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA, 15213, USA
| | - Ye Che
- Medicinal Sciences, Pfizer, Eastern Point Road, Groton, CT, 06340, USA
| | - Reto Horst
- Medicinal Sciences, Pfizer, Eastern Point Road, Groton, CT, 06340, USA
| | - Chris Limberakis
- Medicinal Sciences, Pfizer, Eastern Point Road, Groton, CT, 06340, USA
| | - Justin Bellenger
- Medicinal Sciences, Pfizer, Eastern Point Road, Groton, CT, 06340, USA
| | - Ricardo Lira
- Medicinal Sciences, Pfizer, Eastern Point Road, Groton, CT, 06340, USA
| | | | - Roberto R Gil
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA, 15213, USA
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6
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Farley KA, Koos MRM, Che Y, Horst R, Limberakis C, Bellenger J, Lira R, Gil‐Silva LF, Gil RR. Cross‐Linked Poly‐4‐Acrylomorpholine: A Flexible and Reversibly Compressible Aligning Gel for Anisotropic NMR Analysis of Peptides and Small Molecules in Water. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202106794] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
| | - Martin R. M. Koos
- Department of Chemistry Carnegie Mellon University 4400 Fifth Avenue Pittsburgh PA 15213 USA
| | - Ye Che
- Medicinal Sciences Pfizer Eastern Point Road Groton CT 06340 USA
| | - Reto Horst
- Medicinal Sciences Pfizer Eastern Point Road Groton CT 06340 USA
| | - Chris Limberakis
- Medicinal Sciences Pfizer Eastern Point Road Groton CT 06340 USA
| | - Justin Bellenger
- Medicinal Sciences Pfizer Eastern Point Road Groton CT 06340 USA
| | - Ricardo Lira
- Medicinal Sciences Pfizer Eastern Point Road Groton CT 06340 USA
| | | | - Roberto R. Gil
- Department of Chemistry Carnegie Mellon University 4400 Fifth Avenue Pittsburgh PA 15213 USA
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7
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Chiliveri SC, Robertson AJ, Shen Y, Torchia DA, Bax A. Advances in NMR Spectroscopy of Weakly Aligned Biomolecular Systems. Chem Rev 2021; 122:9307-9330. [PMID: 34766756 DOI: 10.1021/acs.chemrev.1c00730] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The measurement and application of residual dipolar couplings (RDCs) in solution NMR studies of biological macromolecules has become well established over the past quarter of a century. Numerous methods for generating the requisite anisotropic orientational molecular distribution have been demonstrated, each with its specific strengths and weaknesses. In parallel, an enormous number of pulse schemes have been introduced to measure the many different types of RDCs, ranging from the most widely measured backbone amide 15N-1H RDCs, to 1H-1H RDCs and couplings between low-γ nuclei. Applications of RDCs range from structure validation and refinement to the determination of relative domain orientations, the measurement of backbone and domain motions, and de novo structure determination. Nevertheless, it appears that the power of the RDC methodology remains underutilized. This review aims to highlight the practical aspects of sample preparation and RDC measurement while describing some of the most straightforward applications that take advantage of the exceptionally precise information contained in such data. Some emphasis will be placed on more recent developments that enable the accurate measurement of RDCs in larger systems, which is key to the ongoing shift in focus of biological NMR spectroscopy from structure determination toward gaining improved understanding of how molecular flexibility drives protein function.
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Affiliation(s)
- Sai Chaitanya Chiliveri
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Angus J Robertson
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Yang Shen
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Dennis A Torchia
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Ad Bax
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, United States
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8
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Rizzo D, Cerofolini L, Pérez-Ràfols A, Giuntini S, Baroni F, Ravera E, Luchinat C, Fragai M. Evaluation of the Higher Order Structure of Biotherapeutics Embedded in Hydrogels for Bioprinting and Drug Release. Anal Chem 2021; 93:11208-11214. [PMID: 34339178 PMCID: PMC8382223 DOI: 10.1021/acs.analchem.1c01850] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 07/20/2021] [Indexed: 01/16/2023]
Abstract
Biocompatible hydrogels for tissue regeneration/replacement and drug release with specific architectures can be obtained by three-dimensional bioprinting techniques. The preservation of the higher order structure of the proteins embedded in the hydrogels as drugs or modulators is critical for their biological activity. Solution nuclear magnetic resonance (NMR) experiments are currently used to investigate the higher order structure of biotherapeutics in comparability, similarity, and stability studies. However, the size of pores in the gel, protein-matrix interactions, and the size of the embedded proteins often prevent the use of this methodology. The recent advancements of solid-state NMR allow for the comparison of the higher order structure of the matrix-embedded and free isotopically enriched proteins, allowing for the evaluation of the functionality of the material in several steps of hydrogel development. Moreover, the structural information at atomic detail on the matrix-protein interactions paves the way for a structure-based design of these biomaterials.
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Affiliation(s)
- Domenico Rizzo
- Magnetic
Resonance Center (CERM), University of Florence,
and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine
(CIRMMP), Via L. Sacconi 6, Sesto Fiorentino 50019, Italy
- Department
of Chemistry “Ugo Schiff”, University of Florence, Via della Lastruccia 3, Sesto Fiorentino 50019, Italy
| | - Linda Cerofolini
- Magnetic
Resonance Center (CERM), University of Florence,
and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine
(CIRMMP), Via L. Sacconi 6, Sesto Fiorentino 50019, Italy
| | - Anna Pérez-Ràfols
- Department
of Chemistry “Ugo Schiff”, University of Florence, Via della Lastruccia 3, Sesto Fiorentino 50019, Italy
- Giotto
Biotech, S.R.L, Via Madonna
del piano 6, Sesto Fiorentino, Florence 50019, Italy
| | - Stefano Giuntini
- Magnetic
Resonance Center (CERM), University of Florence,
and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine
(CIRMMP), Via L. Sacconi 6, Sesto Fiorentino 50019, Italy
- Department
of Chemistry “Ugo Schiff”, University of Florence, Via della Lastruccia 3, Sesto Fiorentino 50019, Italy
| | - Fabio Baroni
- Analytical
Development Biotech Department, Merck Serono
S.p.a, Merck KGaA, Guidonia, Rome 00012, Italy
| | - Enrico Ravera
- Magnetic
Resonance Center (CERM), University of Florence,
and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine
(CIRMMP), Via L. Sacconi 6, Sesto Fiorentino 50019, Italy
- Department
of Chemistry “Ugo Schiff”, University of Florence, Via della Lastruccia 3, Sesto Fiorentino 50019, Italy
| | - Claudio Luchinat
- Magnetic
Resonance Center (CERM), University of Florence,
and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine
(CIRMMP), Via L. Sacconi 6, Sesto Fiorentino 50019, Italy
- Department
of Chemistry “Ugo Schiff”, University of Florence, Via della Lastruccia 3, Sesto Fiorentino 50019, Italy
| | - Marco Fragai
- Magnetic
Resonance Center (CERM), University of Florence,
and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine
(CIRMMP), Via L. Sacconi 6, Sesto Fiorentino 50019, Italy
- Department
of Chemistry “Ugo Schiff”, University of Florence, Via della Lastruccia 3, Sesto Fiorentino 50019, Italy
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9
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Ji D, Kim J. Recent Strategies for Strengthening and Stiffening Tough Hydrogels. ADVANCED NANOBIOMED RESEARCH 2021. [DOI: 10.1002/anbr.202100026] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Affiliation(s)
- Donghwan Ji
- School of Chemical Engineering Sungkyunkwan University (SKKU) Suwon 16419 Republic of Korea
| | - Jaeyun Kim
- School of Chemical Engineering Sungkyunkwan University (SKKU) Suwon 16419 Republic of Korea
- Department of Health Sciences and Technology Samsung Advanced Institute for Health Science and Technology (SAIHST) Sungkyunkwan University (SKKU) Suwon 16419 Republic of Korea
- Biomedical Institute for Convergence at SKKU (BICS) Sungkyunkwan University (SKKU) Suwon 16419 Republic of Korea
- Institute of Quantum Biophysics (IQB) Sungkyunkwan University (SKKU) Suwon 16419 Republic of Korea
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10
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Ibáñez de Opakua A, Zweckstetter M. Extending the applicability of P3D for structure determination of small molecules. MAGNETIC RESONANCE (GOTTINGEN, GERMANY) 2021; 2:105-116. [PMID: 37904779 PMCID: PMC10539764 DOI: 10.5194/mr-2-105-2021] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Accepted: 03/15/2021] [Indexed: 11/01/2023]
Abstract
The application of anisotropic nuclear magnetic resonance (NMR) parameters for the correct structural assignment of small molecules requires the use of partially ordered media. Previously we demonstrated that the use of P3D simulations using poly(γ -benzyl-L-glutamate) (PBLG) as an alignment medium allows for the determination of the correct diastereomer from extremely sparse NMR data. Through the analysis of the structural characteristics of small molecules in different alignment media, here we show that when steric or electrostatic factors dominate the alignment, P3D-PBLG retains its diastereomer discrimination power. We also demonstrate that P3D simulations can define the different conformations of a flexible small molecule from sparse NMR data.
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Affiliation(s)
- Alain Ibáñez de Opakua
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold-Str. 3a, 37075 Göttingen, Germany
| | - Markus Zweckstetter
- German Center for Neurodegenerative Diseases (DZNE), Von-Siebold-Str. 3a, 37075 Göttingen, Germany
- Department for NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, Am Faßberg 11, 37077 Göttingen, Germany
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11
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Wang Y, An L, Yang Y, Yao L. Generating Five Independent Molecular Alignments for Simultaneous Protein Structure and Dynamics Determination Using Nuclear Magnetic Resonance Spectroscopy. Anal Chem 2020; 92:15263-15269. [PMID: 33166130 DOI: 10.1021/acs.analchem.0c02882] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Residual dipolar couplings (RDCs) are commonly used in NMR for protein structure and dynamics studies, but it is challenging to generate five independent RDC data sets (required for simultaneous structure and dynamics determination) for most protein molecules in the magnetic field. In this work, a reporter protein with a lanthanide tag is introduced to create five independent alignments. This reporter protein is then attached to target proteins where five independent sets of RDCs are also obtained for the target proteins. The fitting of RDCs provides important information about the structure and dynamics of the target proteins. The method is simple and effective and, in principle, can be used to generate complete sets of RDCs for different protein molecules.
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Affiliation(s)
| | - Liaoyuan An
- University of Chinese Academy of Sciences, Beijing 100049, China
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12
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Giassa IC, Vavrinská A, Zelinka J, Šebera J, Sychrovský V, Boelens R, Fiala R, Trantírek L. HERMES - A Software Tool for the Prediction and Analysis of Magnetic-Field-Induced Residual Dipolar Couplings in Nucleic Acids. Chempluschem 2020; 85:2177-2185. [PMID: 32986260 DOI: 10.1002/cplu.202000505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/31/2020] [Indexed: 11/06/2022]
Abstract
Field-Induced Residual Dipolar Couplings (fiRDC) are a valuable source of long-range information on structure of nucleic acids (NA) in solution. A web application (HERMES) was developed for structure-based prediction and analysis of the (fiRDCs) in NA. fiRDC prediction is based on input 3D model structure(s) of NA and a built-in library of nucleobase-specific magnetic susceptibility tensors and reference geometries. HERMES allows three basic applications: (i) the prediction of fiRDCs for a given structural model of NAs, (ii) the validation of experimental or modeled NA structures using experimentally derived fiRDCs, and (iii) assessment of the oligomeric state of the NA fragment and/or the identification of a molecular NA model that is consistent with experimentally derived fiRDC data. Additionally, the program's built-in routine for rigid body modeling allows the evaluation of relative orientation of domains within NA that is in agreement with experimental fiRDCs.
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Affiliation(s)
| | - Andrea Vavrinská
- Bijvoet Centre for Biomolecular Research, Utrecht University, Utrecht, 3584 CH, The Netherlands
| | - Jiří Zelinka
- Department of Mathematics and Statistics, Faculty of Science, Masaryk University, Brno, 611 37, Czech Republic
| | - Jakub Šebera
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague, 166 10, Czech Republic
| | - Vladimír Sychrovský
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague, 166 10, Czech Republic
| | - Rolf Boelens
- Bijvoet Centre for Biomolecular Research, Utrecht University, Utrecht, 3584 CH, The Netherlands
| | - Radovan Fiala
- Central European Institute of Technology, Masaryk University, Brno
| | - Lukáš Trantírek
- Central European Institute of Technology, Masaryk University, Brno
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13
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Wang Y, McKinstry AH, Burke KA. Main-Chain Liquid Crystalline Hydrogels that Support 3D Stem Cell Culture. Biomacromolecules 2020; 21:2365-2375. [DOI: 10.1021/acs.biomac.0c00316] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Yongjian Wang
- Chemical and Biomolecular Engineering, University of Connecticut, 191 Auditorium Road Unit 3222, Storrs, Connecticut 06269-3222, United States
| | - Amy H. McKinstry
- Chemical and Biomolecular Engineering, University of Connecticut, 191 Auditorium Road Unit 3222, Storrs, Connecticut 06269-3222, United States
| | - Kelly A. Burke
- Chemical and Biomolecular Engineering, University of Connecticut, 191 Auditorium Road Unit 3222, Storrs, Connecticut 06269-3222, United States
- Polymer Program, Institute of Materials Science, University of Connecticut, 97 North Eagleville Road Unit 3136, Storrs, Connecticut 06269-3136, United States
- Biomedical Engineering, University of Connecticut, 260 Glenbrook Road Unit 3247, Storrs, Connecticut 06269-3247, United States
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14
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Delhommel F, Gabel F, Sattler M. Current approaches for integrating solution NMR spectroscopy and small-angle scattering to study the structure and dynamics of biomolecular complexes. J Mol Biol 2020; 432:2890-2912. [DOI: 10.1016/j.jmb.2020.03.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 02/27/2020] [Accepted: 03/10/2020] [Indexed: 01/24/2023]
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15
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Fargason T, Wang T, De Silva NIU, Zhang Z, McKelvey H, Knapp T, Zaharias S, Zhang J. Amide additives improve RDC measurements in polyacrylamide. JOURNAL OF BIOMOLECULAR NMR 2020; 74:119-124. [PMID: 32056065 DOI: 10.1007/s10858-020-00305-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 02/08/2020] [Indexed: 06/10/2023]
Abstract
Residual dipolar couplings (RDCs) provide valuable NMR parameters that can be used for structural calculation and verification. Measuring RDCs requires aligning macromolecules using one of various types of alignment media. Of different alignment media options, stretched or compressed polyacrylamide gels are advantageous due to their chemical stability. However, polyacrylamide interacts with proteins and significantly broadens NMR resonances. In this study, we found that the amide-containing compounds asparagine, glutamine and propionamide improve spectral quality of proteins in polyacrylamide gel without significantly reducing the magnitude of RDC values. Moreover, we showed that propionamide is an attractive additive that increases protein solubility without interfering with protein stability, ligand binding or NMR pulse width, suggesting its potential applications for our NMR methods.
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Affiliation(s)
- Talia Fargason
- Department of Chemistry, College of Arts and Sciences, University of Alabama at Birmingham, CH266, 901 14th Street South, Birmingham, AL, 35294-1240, USA
| | - Ting Wang
- Department of Chemistry, College of Arts and Sciences, University of Alabama at Birmingham, CH266, 901 14th Street South, Birmingham, AL, 35294-1240, USA
| | - Naiduwadura Ivon Upekala De Silva
- Department of Chemistry, College of Arts and Sciences, University of Alabama at Birmingham, CH266, 901 14th Street South, Birmingham, AL, 35294-1240, USA
| | - Zihan Zhang
- Department of Chemistry, College of Arts and Sciences, University of Alabama at Birmingham, CH266, 901 14th Street South, Birmingham, AL, 35294-1240, USA
| | - Heather McKelvey
- Department of Chemistry, College of Arts and Sciences, University of Alabama at Birmingham, CH266, 901 14th Street South, Birmingham, AL, 35294-1240, USA
| | - Taylor Knapp
- Department of Chemistry, College of Arts and Sciences, University of Alabama at Birmingham, CH266, 901 14th Street South, Birmingham, AL, 35294-1240, USA
| | - Steve Zaharias
- Department of Chemistry, College of Arts and Sciences, University of Alabama at Birmingham, CH266, 901 14th Street South, Birmingham, AL, 35294-1240, USA
| | - Jun Zhang
- Department of Chemistry, College of Arts and Sciences, University of Alabama at Birmingham, CH266, 901 14th Street South, Birmingham, AL, 35294-1240, USA.
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16
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Lesot P, Aroulanda C, Berdagué P, Meddour A, Merlet D, Farjon J, Giraud N, Lafon O. Multinuclear NMR in polypeptide liquid crystals: Three fertile decades of methodological developments and analytical challenges. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2020; 116:85-154. [PMID: 32130960 DOI: 10.1016/j.pnmrs.2019.10.001] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 10/24/2019] [Indexed: 06/10/2023]
Abstract
NMR spectroscopy of oriented samples makes accessible residual anisotropic intramolecular NMR interactions, such as chemical shift anisotropy (RCSA), dipolar coupling (RDC), and quadrupolar coupling (RQC), while preserving high spectral resolution. In addition, in a chiral aligned environment, enantiomers of chiral molecules or enantiopic elements of prochiral compounds adopt different average orientations on the NMR timescale, and hence produce distinct NMR spectra or signals. NMR spectroscopy in chiral aligned media is a powerful analytical tool, and notably provides unique information on (pro)chirality analysis, natural isotopic fractionation, stereochemistry, as well as molecular conformation and configuration. Significant progress has been made in this area over the three last decades, particularly using polypeptide-based chiral liquid crystals (CLCs) made of organic solutions of helically chiral polymers (as PBLG) in organic solvents. This review presents an overview of NMR in polymeric LCs. In particular, we describe the theoretical tools and the major NMR methods that have been developed and applied to study (pro)chiral molecules dissolved in such oriented solvents. We also discuss the representative applications illustrating the analytical potential of this original NMR tool. This overview article is dedicated to thirty years of original contributions to the development of NMR spectroscopy in polypeptide-based chiral liquid crystals.
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Affiliation(s)
- Philippe Lesot
- Université Paris Sud/Université Paris-Saclay, UMR CNRS 8182, Institut de Chimie Moléculaire et des Matériaux d'Orsay, ICMMO, Equipe RMN en Milieu Orienté, Bât. 410, 15 rue du Doyen Georges Poitou, F-91405 Orsay cedex, France; Centre National de la Recherche Scientifique (CNRS), France.
| | - Christie Aroulanda
- Université Paris Sud/Université Paris-Saclay, UMR CNRS 8182, Institut de Chimie Moléculaire et des Matériaux d'Orsay, ICMMO, Equipe RMN en Milieu Orienté, Bât. 410, 15 rue du Doyen Georges Poitou, F-91405 Orsay cedex, France
| | - Philippe Berdagué
- Université Paris Sud/Université Paris-Saclay, UMR CNRS 8182, Institut de Chimie Moléculaire et des Matériaux d'Orsay, ICMMO, Equipe RMN en Milieu Orienté, Bât. 410, 15 rue du Doyen Georges Poitou, F-91405 Orsay cedex, France
| | - Abdelkrim Meddour
- Université Paris Sud/Université Paris-Saclay, UMR CNRS 8182, Institut de Chimie Moléculaire et des Matériaux d'Orsay, ICMMO, Equipe RMN en Milieu Orienté, Bât. 410, 15 rue du Doyen Georges Poitou, F-91405 Orsay cedex, France
| | - Denis Merlet
- Université Paris Sud/Université Paris-Saclay, UMR CNRS 8182, Institut de Chimie Moléculaire et des Matériaux d'Orsay, ICMMO, Equipe RMN en Milieu Orienté, Bât. 410, 15 rue du Doyen Georges Poitou, F-91405 Orsay cedex, France
| | - Jonathan Farjon
- Centre National de la Recherche Scientifique (CNRS), France; Faculté des Sciences et Techniques de Nantes, UMR CNRS 6230, Chimie et Interdisciplinarité, Synthèse, Analyse, Modélisation, CEISAM, Equipe EBSI, BP 92208, 2 rue de la Houssinière, F-44322 Nantes cedex 3, France
| | - Nicolas Giraud
- Université Paris Descartes, Sorbonne Paris Cité, UMR CNRS 8601, Laboratory of Pharmacological and Toxicological Chemistry and Biochemistry, LPTCB, 45 rue des Saints Pères, F-75006 Paris, France
| | - Olivier Lafon
- Universite de Lille, CNRS, Centrale Lille, ENSCL, Univ. Artois, UMR CNRS 8181, Unité de Catalyse et Chimie du Solide, UCCS, F-59000 Lille, France; Institut Universitaire de France (IUF), France
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17
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Affiliation(s)
- Darón I. Freedberg
- Center for Biologics Evaluation and ResearchFood and Drug Administration 10903 New Hampshire Ave. Silver Spring MD. 20993
| | - Jeahoo Kwon
- Center for Biologics Evaluation and ResearchFood and Drug Administration 10903 New Hampshire Ave. Silver Spring MD. 20993
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18
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Bibow S. Opportunities and Challenges of Backbone, Sidechain, and RDC Experiments to Study Membrane Protein Dynamics in a Detergent-Free Lipid Environment Using Solution State NMR. Front Mol Biosci 2019; 6:103. [PMID: 31709261 PMCID: PMC6823230 DOI: 10.3389/fmolb.2019.00103] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 09/19/2019] [Indexed: 12/22/2022] Open
Abstract
Whereas solution state NMR provided a wealth of information on the dynamics landscape of soluble proteins, only few studies have investigated membrane protein dynamics in a detergent-free lipid environment. Recent developments of smaller nanodiscs and other lipid-scaffolding polymers, such as styrene maleic acid (SMA), however, open new and promising avenues to explore the function-dynamics relationship of membrane proteins as well as between membrane proteins and their surrounding lipid environment. Favorably sized lipid-bilayer nanodiscs, established membrane protein reconstitution protocols and sophisticated solution NMR relaxation methods probing dynamics over a wide range of timescales will eventually reveal unprecedented lipid-membrane protein interdependencies that allow us to explain things we have not been able to explain so far. In particular, methyl group dynamics resulting from CEST, CPMG, ZZ exchange, and RDC experiments are expected to provide new and surprising insights due to their proximity to lipids, their applicability in large 100+ kDa assemblies and their simple labeling due to the availability of commercial precursors. This review summarizes the recent developments of membrane protein dynamics with a special focus on membrane protein dynamics in lipid-bilayer nanodiscs. Opportunities and challenges of backbone, side chain and RDC dynamics applied to membrane proteins are discussed. Solution-state NMR and lipid nanodiscs bear great potential to change our molecular understanding of lipid-membrane protein interactions.
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Affiliation(s)
- Stefan Bibow
- Biozentrum, University of Basel, Basel, Switzerland
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19
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Engineering selective competitors for the discrimination of highly conserved protein-protein interaction modules. Nat Commun 2019; 10:4521. [PMID: 31586061 PMCID: PMC6778148 DOI: 10.1038/s41467-019-12528-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Accepted: 09/14/2019] [Indexed: 12/13/2022] Open
Abstract
Designing highly specific modulators of protein-protein interactions (PPIs) is especially challenging in the context of multiple paralogs and conserved interaction surfaces. In this case, direct generation of selective and competitive inhibitors is hindered by high similarity within the evolutionary-related protein interfaces. We report here a strategy that uses a semi-rational approach to separate the modulator design into two functional parts. We first achieve specificity toward a region outside of the interface by using phage display selection coupled with molecular and cellular validation. Highly selective competition is then generated by appending the more degenerate interaction peptide to contact the target interface. We apply this approach to specifically bind a single PDZ domain within the postsynaptic protein PSD-95 over highly similar PDZ domains in PSD-93, SAP-97 and SAP-102. Our work provides a paralog-selective and domain specific inhibitor of PSD-95, and describes a method to efficiently target other conserved PPI modules. Developing inhibitors that target specific protein-protein interactions (PPIs) is challenging. Here, the authors show that target selectivity and PPI blocking can be achieved simultaneously with PPI inhibitors that contain two functional modules, and create a paralog-selective PSD-95 inhibitor as proof-of-concept.
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20
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Lorieau JL. Partial alignment, residual dipolar couplings and molecular symmetry in solution NMR. JOURNAL OF BIOMOLECULAR NMR 2019; 73:477-491. [PMID: 31407205 DOI: 10.1007/s10858-019-00256-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 06/06/2019] [Indexed: 06/10/2023]
Abstract
Residual dipolar couplings (RDCs) and residual anisotropic chemical shifts (RACSs) are produced by the partial alignment of solution NMR samples. RDCs and RACSs yield high-resolution structural and dynamic information on the orientation of bonds and chemical groups in molecules. Many molecules form oligomers or have intrinsic symmetries, which may simplify the analysis of their partial alignment datasets. In this report, we explore the theory of partial alignment using an irreducible spherical representation, and we investigate the impact of molecular symmetry on the alignment of molecules. Though previous studies have reported simplified relationships on the partial alignment of molecules bearing different symmetry groups, we show that these simplified relationships may not be universal and only apply to a limited set of systems.
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Affiliation(s)
- Justin L Lorieau
- Department of Chemistry, University of Illinois at Chicago, 4500 SES, 845 W Taylor St, Chicago, IL, 60607, USA.
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21
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Structure and ligand binding of As-p18, an extracellular fatty acid binding protein from the eggs of a parasitic nematode. Biosci Rep 2019; 39:BSR20191292. [PMID: 31273060 PMCID: PMC6646235 DOI: 10.1042/bsr20191292] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 06/26/2019] [Accepted: 07/02/2019] [Indexed: 02/02/2023] Open
Abstract
Intracellular lipid-binding proteins (iLBPs) of the fatty acid-binding protein (FABP) family of animals transport, mainly fatty acids or retinoids, are confined to the cytosol and have highly similar 3D structures. In contrast, nematodes possess fatty acid-binding proteins (nemFABPs) that are secreted into the perivitelline fluid surrounding their developing embryos. We report structures of As-p18, a nemFABP of the large intestinal roundworm Ascaris suum, with ligand bound, determined using X-ray crystallography and nuclear magnetic resonance spectroscopy. In common with other FABPs, As-p18 comprises a ten β-strand barrel capped by two short α-helices, with the carboxylate head group of oleate tethered in the interior of the protein. However, As-p18 exhibits two distinctive longer loops amongst β-strands not previously seen in a FABP. One of these is adjacent to the presumed ligand entry portal, so it may help to target the protein for efficient loading or unloading of ligand. The second, larger loop is at the opposite end of the molecule and has no equivalent in any iLBP structure yet determined. As-p18 preferentially binds a single 18-carbon fatty acid ligand in its central cavity but in an orientation that differs from iLBPs. The unusual structural features of nemFABPs may relate to resourcing of developing embryos of nematodes.
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22
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Feng Q, Xu J, Zhang K, Yao H, Zheng N, Zheng L, Wang J, Wei K, Xiao X, Qin L, Bian L. Dynamic and Cell-Infiltratable Hydrogels as Injectable Carrier of Therapeutic Cells and Drugs for Treating Challenging Bone Defects. ACS CENTRAL SCIENCE 2019; 5:440-450. [PMID: 30937371 PMCID: PMC6439455 DOI: 10.1021/acscentsci.8b00764] [Citation(s) in RCA: 127] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Indexed: 05/24/2023]
Abstract
Biopolymeric hydrogels have been widely used as carriers of therapeutic cells and drugs for biomedical applications. However, most conventional hydrogels cannot be injected after gelation and do not support the infiltration of cells because of the static nature of their network structure. Here, we develop unique cell-infiltratable and injectable (Ci-I) gelatin hydrogels, which are physically cross-linked by weak and highly dynamic host-guest complexations and are further reinforced by limited chemical cross-linking for enhanced stability, and then demonstrate the outstanding properties of these Ci-I gelatin hydrogels. The highly dynamic network of Ci-I hydrogels allows injection of prefabricated hydrogels with encapsulated cells and drugs, thereby simplifying administration during surgery. Furthermore, the reversible nature of the weak host-guest cross-links enables infiltration and migration of external cells into Ci-I gelatin hydrogels, thereby promoting the participation of endogenous cells in the healing process. Our findings show that Ci-I hydrogels can mediate sustained delivery of small hydrophobic molecular drugs (e.g., icaritin) to boost differentiation of stem cells while avoiding the adverse effects (e.g., in treatment of bone necrosis) associated with high drug dosage. The injection of Ci-I hydrogels encapsulating mesenchymal stem cells (MSCs) and drug (icaritin) efficiently prevented the decrease in bone mineral density (BMD) and promoted in situ bone regeneration in an animal model of steroid-associated osteonecrosis (SAON) of the hip by creating the microenvironment favoring the osteogenic differentiation of MSCs, including the recruited endogenous cells. We believe that this is the first demonstration on applying injectable hydrogels as effective carriers of therapeutic cargo for treating dysfunctions in deep and enclosed anatomical sites via a minimally invasive procedure.
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Affiliation(s)
- Qian Feng
- Fujian
Provincial Key Laboratory of Advanced Materials Oriented Chemical
Engineering, College of Chemistry and Materials Science, Fujian Normal University, Fuzhou 350007, China
- Department
of Biomedical Engineering, The Chinese University
of Hong Kong, William M.W. Mong Building, Shatin, Hong Kong
SAR, China
| | - Jiankun Xu
- Department
of Orthopaedic and Traumatology and Innovative Orthopaedic Biomaterial
and Drug Translational Research Laboratory of Li Ka Shing Institute
of Health, Faculty of Medicine, The Chinese
University of Hong Kong, Hong Kong
SAR, China
| | - Kunyu Zhang
- Department
of Biomedical Engineering, The Chinese University
of Hong Kong, William M.W. Mong Building, Shatin, Hong Kong
SAR, China
| | - Hao Yao
- Department
of Orthopaedic and Traumatology and Innovative Orthopaedic Biomaterial
and Drug Translational Research Laboratory of Li Ka Shing Institute
of Health, Faculty of Medicine, The Chinese
University of Hong Kong, Hong Kong
SAR, China
| | - Nianye Zheng
- Department
of Orthopaedic and Traumatology and Innovative Orthopaedic Biomaterial
and Drug Translational Research Laboratory of Li Ka Shing Institute
of Health, Faculty of Medicine, The Chinese
University of Hong Kong, Hong Kong
SAR, China
| | - Lizhen Zheng
- Department
of Orthopaedic and Traumatology and Innovative Orthopaedic Biomaterial
and Drug Translational Research Laboratory of Li Ka Shing Institute
of Health, Faculty of Medicine, The Chinese
University of Hong Kong, Hong Kong
SAR, China
| | - Jiali Wang
- Department
of Orthopaedic and Traumatology and Innovative Orthopaedic Biomaterial
and Drug Translational Research Laboratory of Li Ka Shing Institute
of Health, Faculty of Medicine, The Chinese
University of Hong Kong, Hong Kong
SAR, China
| | - Kongchang Wei
- Department
of Biomedical Engineering, The Chinese University
of Hong Kong, William M.W. Mong Building, Shatin, Hong Kong
SAR, China
- Laboratory
for Biomimetic Membranes and Textiles, Empa,
Swiss Federal Laboratories for Materials Science and Technology, 9014 St., Gallen, Switzerland
| | - Xiufeng Xiao
- Fujian
Provincial Key Laboratory of Advanced Materials Oriented Chemical
Engineering, College of Chemistry and Materials Science, Fujian Normal University, Fuzhou 350007, China
| | - Ling Qin
- Department
of Orthopaedic and Traumatology and Innovative Orthopaedic Biomaterial
and Drug Translational Research Laboratory of Li Ka Shing Institute
of Health, Faculty of Medicine, The Chinese
University of Hong Kong, Hong Kong
SAR, China
| | - Liming Bian
- Department
of Biomedical Engineering, The Chinese University
of Hong Kong, William M.W. Mong Building, Shatin, Hong Kong
SAR, China
- Translational
Research Centre of Regenerative Medicine and 3D Printing Technologies
of Guangzhou Medical University, The Third
Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong 510150, China
- Shenzhen
Research Institute, The Chinese University
of Hong Kong, Shenzhen 518172, China
- China
Orthopedic Regenerative Medicine Group (CORMed), Hangzhou 310058, China
- Centre
for Novel Biomaterials, The Chinese University
of Hong Kong, Hong Kong SAR, China
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23
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Application of anisotropic NMR parameters to the confirmation of molecular structure. Nat Protoc 2018; 14:217-247. [DOI: 10.1038/s41596-018-0091-9] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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24
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Milles S, Salvi N, Blackledge M, Jensen MR. Characterization of intrinsically disordered proteins and their dynamic complexes: From in vitro to cell-like environments. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2018; 109:79-100. [PMID: 30527137 DOI: 10.1016/j.pnmrs.2018.07.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2018] [Revised: 07/16/2018] [Accepted: 07/16/2018] [Indexed: 05/08/2023]
Abstract
Over the last two decades, it has become increasingly clear that a large fraction of the human proteome is intrinsically disordered or contains disordered segments of significant length. These intrinsically disordered proteins (IDPs) play important regulatory roles throughout biology, underlining the importance of understanding their conformational behavior and interaction mechanisms at the molecular level. Here we review recent progress in the NMR characterization of the structure and dynamics of IDPs in various functional states and environments. We describe the complementarity of different NMR parameters for quantifying the conformational propensities of IDPs in their isolated and phosphorylated states, and we discuss the challenges associated with obtaining structural models of dynamic protein-protein complexes involving IDPs. In addition, we review recent progress in understanding the conformational behavior of IDPs in cell-like environments such as in the presence of crowding agents, in membrane-less organelles and in the complex environment of the human cell.
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Affiliation(s)
- Sigrid Milles
- Univ. Grenoble Alpes, CNRS, CEA, IBS, F-38000 Grenoble, France
| | - Nicola Salvi
- Univ. Grenoble Alpes, CNRS, CEA, IBS, F-38000 Grenoble, France
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25
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Niklas T, Schulze P, Farès C. Cromolyn/gelatin mixtures as aqueous alignment media and utilization of their mechanical stability for a layering technique. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2018; 56:1176-1182. [PMID: 30091791 DOI: 10.1002/mrc.4786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 07/26/2018] [Accepted: 07/27/2018] [Indexed: 06/08/2023]
Abstract
In this study, aqueous blends of cromolyn and gelatin ("cromogels") are introduced as anisotropic media. The addition of gelatin enables an advantageous adjustability of the strength, the homogeneity, and the stability of the cromolyn alignment. The mechanical stability of these polymer-dispersed liquid crystals is further utilized by stacking layers of D2 O/cromolyn/gelatin with varying component ratio. The resulting distinct phases with correspondingly different degrees of alignment can be targeted by spatially resolved NMR techniques. As a case study, we investigated sucrose in a two-phase system with neat D2 O and analyte layered over the anisotropic medium. A recently presented spatially selective coupled-type HSQC experiment allows the determination of one-bond C-H splitting in both phases.
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Affiliation(s)
- Thomas Niklas
- Chromatography Department, Max-Planck-Institut für Kohlenforschung, Mülheim an der Ruhr, Germany
- NMR Department, Max-Planck-Institut für Kohlenforschung, Mülheim an der Ruhr, Germany
| | - Philipp Schulze
- Chromatography Department, Max-Planck-Institut für Kohlenforschung, Mülheim an der Ruhr, Germany
| | - Christophe Farès
- NMR Department, Max-Planck-Institut für Kohlenforschung, Mülheim an der Ruhr, Germany
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26
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Rigling C, Kisunzu JK, Duschmalé J, Häussinger D, Wiesner M, Ebert MO, Wennemers H. Conformational Properties of a Peptidic Catalyst: Insights from NMR Spectroscopic Studies. J Am Chem Soc 2018; 140:10829-10838. [PMID: 30106584 DOI: 10.1021/jacs.8b05459] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Peptides have become valuable as catalysts for a variety of different reactions, but little is known about the conformational properties of peptidic catalysts. We investigated the conformation of the peptide H-dPro-Pro-Glu-NH2, a highly reactive and stereoselective catalyst for conjugate addition reactions, and the corresponding enamine intermediate in solution by NMR spectroscopy and computational methods. The combination of nuclear Overhauser effects (NOEs), residual dipolar couplings (RDCs), J-couplings, and temperature coefficients revealed that the tripeptide adopts a single predominant conformation in its ground state. The structure is a type I β-turn, which gains stabilization from three hydrogen bonds that are cooperatively formed between all functional groups (secondary amine, carboxylic acid, amides) within the tripeptide. In contrast, the conformation of the enamine intermediate is significantly more flexible. The conformational ensemble of the enamine is still dominated by the β-turn, but the backbone and the side chain of the glutamic acid residue are more dynamic. The key to the switch between rigidity and flexibility of the peptidic catalyst is the CO2H group in the side chain of the glutamic acid residue, which acts as a lid that can open and close. As a result, the peptidic catalyst is able to adapt to the structural requirements of the intermediates and transition states of the catalytic cycle. These insights might explain the robustness and high reactivity of the peptidic catalyst, which exceeds that of other secondary amine-based organocatalysts. The data suggest that a balance between rigidity and flexibility, which is reminiscent of the dynamic nature of enzymes, is beneficial for peptidic catalysts and other synthetic catalysts.
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Affiliation(s)
- Carla Rigling
- Laboratorium für Organische Chemie , ETH Zürich , D-CHAB, Vladimir-Prelog-Weg 3 , 8093 Zürich , Switzerland
| | - Jessica K Kisunzu
- Laboratorium für Organische Chemie , ETH Zürich , D-CHAB, Vladimir-Prelog-Weg 3 , 8093 Zürich , Switzerland
| | - Jörg Duschmalé
- Laboratorium für Organische Chemie , ETH Zürich , D-CHAB, Vladimir-Prelog-Weg 3 , 8093 Zürich , Switzerland.,Department of Chemistry , University of Basel , St. Johanns-Ring 19 , 4056 Basel , Switzerland
| | - Daniel Häussinger
- Department of Chemistry , University of Basel , St. Johanns-Ring 19 , 4056 Basel , Switzerland
| | - Markus Wiesner
- Department of Chemistry , University of Basel , St. Johanns-Ring 19 , 4056 Basel , Switzerland
| | - Marc-Olivier Ebert
- Laboratorium für Organische Chemie , ETH Zürich , D-CHAB, Vladimir-Prelog-Weg 3 , 8093 Zürich , Switzerland
| | - Helma Wennemers
- Laboratorium für Organische Chemie , ETH Zürich , D-CHAB, Vladimir-Prelog-Weg 3 , 8093 Zürich , Switzerland
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27
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Liu Y, Cohen RD, Martin GE, Williamson RT. A practical strategy for the accurate measurement of residual dipolar couplings in strongly aligned small molecules. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2018; 291:63-72. [PMID: 29723716 DOI: 10.1016/j.jmr.2018.04.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 04/05/2018] [Accepted: 04/05/2018] [Indexed: 06/08/2023]
Abstract
Accurate measurement of residual dipolar couplings (RDCs) requires an appropriate degree of alignment in order to optimize data quality. An overly weak alignment yields very small anisotropic data that are susceptible to measurement errors, whereas an overly strong alignment introduces extensive anisotropic effects that severely degrade spectral quality. The ideal alignment amplitude also depends on the specific pulse sequence used for the coupling measurement. In this work, we introduce a practical strategy for the accurate measurement of one-bond 13C-1H RDCs up to a range of ca. -300 to +300 Hz, corresponding to an alignment that is an order of magnitude stronger than typically employed for small molecule structural elucidation. This strong alignment was generated in the mesophase of the commercially available poly-γ-(benzyl-L-glutamate) polymer. The total coupling was measured by the simple and well-studied heteronuclear two-dimensional J-resolved experiment, which performs well in the presence of strong anisotropic effects. In order to unequivocally determine the sign of the total coupling and resolve ambiguities in assigning total couplings in the CH2 group, coupling measurements were conducted at an isotropic condition plus two anisotropic conditions of different alignment amplitudes. Most RDCs could be readily extracted from these measurements whereas more complicated spectral effects resulting from strong homonuclear coupling could be interpreted either theoretically or by simulation. Importantly, measurement of these very large RDCs actually offers significantly improved data quality and utility for the structure determination of small organic molecules.
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Affiliation(s)
- Yizhou Liu
- Structure Elucidation Group, Process and Analytical Research and Development, Merck & Co. Inc., 126 East Lincoln Avenue, Rahway, NJ 07065, USA.
| | - Ryan D Cohen
- Structure Elucidation Group, Process and Analytical Research and Development, Merck & Co. Inc., 126 East Lincoln Avenue, Rahway, NJ 07065, USA
| | - Gary E Martin
- Structure Elucidation Group, Process and Analytical Research and Development, Merck & Co. Inc., 126 East Lincoln Avenue, Rahway, NJ 07065, USA
| | - R Thomas Williamson
- Structure Elucidation Group, Process and Analytical Research and Development, Merck & Co. Inc., 126 East Lincoln Avenue, Rahway, NJ 07065, USA
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28
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Hellemann E, Gil RR. New Stretching Method for Aligning Gels: Its Application to the Measurement Residual Chemical Shift Anisotropies (RCSAs) without the Need for Isotropic Shift Correction. Chemistry 2018; 24:3689-3693. [DOI: 10.1002/chem.201704541] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Erich Hellemann
- Department of Chemistry Carnegie Mellon University 4400 Fifth Ave. Pittsburgh PA 15213 USA
| | - Roberto R. Gil
- Department of Chemistry Carnegie Mellon University 4400 Fifth Ave. Pittsburgh PA 15213 USA
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29
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Affiliation(s)
- Koki Sano
- Department of Chemistry and Biotechnology, School of Engineering; The University of Tokyo; Hongo 7-3-1 Bunkyo-ku Tokyo 113-8656 Japan
- RIKEN Center for Emergent Matter Science; Hirosawa 2-1 Wako Saitama 351-0198 Japan
| | - Yasuhiro Ishida
- RIKEN Center for Emergent Matter Science; Hirosawa 2-1 Wako Saitama 351-0198 Japan
| | - Takuzo Aida
- Department of Chemistry and Biotechnology, School of Engineering; The University of Tokyo; Hongo 7-3-1 Bunkyo-ku Tokyo 113-8656 Japan
- RIKEN Center for Emergent Matter Science; Hirosawa 2-1 Wako Saitama 351-0198 Japan
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30
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Sano K, Ishida Y, Aida T. Synthesis of Anisotropic Hydrogels and Their Applications. Angew Chem Int Ed Engl 2018; 57:2532-2543. [DOI: 10.1002/anie.201708196] [Citation(s) in RCA: 207] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Indexed: 12/13/2022]
Affiliation(s)
- Koki Sano
- Department of Chemistry and Biotechnology, School of Engineering; The University of Tokyo; Hongo 7-3-1 Bunkyo-ku Tokyo 113-8656 Japan
- RIKEN Center for Emergent Matter Science; Hirosawa 2-1 Wako Saitama 351-0198 Japan
| | - Yasuhiro Ishida
- RIKEN Center for Emergent Matter Science; Hirosawa 2-1 Wako Saitama 351-0198 Japan
| | - Takuzo Aida
- Department of Chemistry and Biotechnology, School of Engineering; The University of Tokyo; Hongo 7-3-1 Bunkyo-ku Tokyo 113-8656 Japan
- RIKEN Center for Emergent Matter Science; Hirosawa 2-1 Wako Saitama 351-0198 Japan
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31
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Chiliveri SC, Louis JM, Ghirlando R, Baber JL, Bax A. Tilted, Uninterrupted, Monomeric HIV-1 gp41 Transmembrane Helix from Residual Dipolar Couplings. J Am Chem Soc 2017; 140:34-37. [PMID: 29277995 DOI: 10.1021/jacs.7b10245] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Cryo-electron microscopy and X-ray crystallography have shown that the pre- and postfusion states of the HIV-1 gp41 viral coat protein, although very different from one another, each adopt C3 symmetric structures. A stable homotrimeric structure for the transmembrane domain (TM) also was modeled and supported by experimental data. For a C3 symmetric structure, alignment in an anisotropic medium must be axially symmetric, with the unique axis of the alignment tensor coinciding with the C3 axis. However, NMR residual dipolar couplings (RDCs) measured under three different alignment conditions were found to be incompatible with C3 symmetry. Subsequent measurements by paramagnetic relaxation enhancement, analytical ultracentrifugation, and DEER EPR, indicate that the transmembrane domain is monomeric. 15N NMR relaxation data and RDCs show that TM is highly ordered and uninterrupted for a total length of 32 residues, extending well into the membrane proximal external region.
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Affiliation(s)
- Sai Chaitanya Chiliveri
- Laboratory of Chemical Physics and ‡Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - John M Louis
- Laboratory of Chemical Physics and ‡Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Rodolfo Ghirlando
- Laboratory of Chemical Physics and ‡Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - James L Baber
- Laboratory of Chemical Physics and ‡Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Ad Bax
- Laboratory of Chemical Physics and ‡Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
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32
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Azurmendi HF, Battistel MD, Zarb J, Lichaa F, Negrete Virgen A, Shiloach J, Freedberg DI. The β-reducing end in α(2-8)-polysialic acid constitutes a unique structural motif. Glycobiology 2017; 27:900-911. [PMID: 28369425 PMCID: PMC6283323 DOI: 10.1093/glycob/cwx025] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 03/10/2017] [Accepted: 03/14/2017] [Indexed: 12/13/2022] Open
Abstract
Over the years, structural characterizations of α(2-8)-polysialic acid (polySia) in solution have produced inconclusive results. Efforts for obtaining detailed information in this important antigen have focused primarily on the α-linked residues and not on the distinctive characteristics of the terminal ones. The thermodynamically preferred anomeric configuration for the reducing end of sialic acids is β, which has the [I]CO2- group equatorial and the OH ([I]OH2) axial, while for all other residues the CO2- group is axial. We show that this purportedly minor difference has distinct consequences for the structure of α(2-8)-polySia near the reducing end, as the β configuration places the [I]OH2 in a favorable position for the formation of a hydrogen bond with the carboxylate group of the following residue ([II]CO2-). Molecular dynamics (MD) simulations predicted the hydrogen bond, which we subsequently directly detected by NMR. The combination of MD and residual dipolar couplings shows that the net result for the structure of Sia2-βOH is a stable conformation with well-defined hydration and charge patterns, and consistent with experimental NOE-based hydroxyl and aliphatic inter-proton distances. Moreover, we provide evidence that this distinct conformation is preserved on Sia oligosaccharides, thus constituting a motif that determines the structure and dynamics of α(2-8)-polySia for at least the first two residues of the polymer. We suggest the hypothesis that this structural motif sheds light on a longtime puzzling observation for the requirement of 10 residues of α(2-8)-polySia in order to bind effectively to specific antibodies, about four units more than for analogous cases.
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Affiliation(s)
- Hugo F Azurmendi
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, MD 20903, USA
| | - Marcos D Battistel
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, MD 20903, USA
| | - Jasmin Zarb
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, MD 20903, USA
| | - Flora Lichaa
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, MD 20903, USA
| | - Alejandro Negrete Virgen
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, MD 20903, USA
| | - Joseph Shiloach
- Biotechnology Unit, MSC 5522, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Darón I Freedberg
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, MD 20903, USA
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33
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Reller M, Wesp S, Koos MRM, Reggelin M, Luy B. Biphasic Liquid Crystal and the Simultaneous Measurement of Isotropic and Anisotropic Parameters by Spatially Resolved NMR Spectroscopy. Chemistry 2017. [DOI: 10.1002/chem.201702126] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Malin Reller
- Institut für Organische Chemie and Institut für Biologische Grenzflächen 4 - Magnetische Resonanz; Karlsruher Institut für Technologie (KIT); Fritz-Haber-Weg 6 76131 Karlsruhe Germany
| | - Svenja Wesp
- Organische Chemie; Technische Universität Darmstadt; Alarich-Weiss Str. 4 64287 Darmstadt Germany
| | - Martin R. M. Koos
- Institut für Organische Chemie and Institut für Biologische Grenzflächen 4 - Magnetische Resonanz; Karlsruher Institut für Technologie (KIT); Fritz-Haber-Weg 6 76131 Karlsruhe Germany
| | - Michael Reggelin
- Organische Chemie; Technische Universität Darmstadt; Alarich-Weiss Str. 4 64287 Darmstadt Germany
| | - Burkhard Luy
- Institut für Organische Chemie and Institut für Biologische Grenzflächen 4 - Magnetische Resonanz; Karlsruher Institut für Technologie (KIT); Fritz-Haber-Weg 6 76131 Karlsruhe Germany
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34
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Min J, Shih WM, Bellot G. Designing DNA Nanotube Liquid Crystals as a Weak-Alignment Medium for NMR Structure Determination of Membrane Proteins. Methods Mol Biol 2017; 1500:203-215. [PMID: 27813010 DOI: 10.1007/978-1-4939-6454-3_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Thirty percent of the human proteome is composed of membrane proteins that can perform a wide range of cellular functions and communications. They represent the core of modern medicine as the targets of about 50 % of all prescription pharmaceuticals. However, elucidating the structure of membrane proteins has represented a constant challenge, even in the modern era. To date, only a few hundred high-resolution structural models of membrane proteins are available. This chapter describes the emergence of DNA nanotechnology as a powerful tool for the structural characterization of membrane protein using solution-state nuclear magnetic resonance (NMR) spectroscopy. Here, we detail the large-scale synthesis of detergent-resistant DNA nanotubes that can be assembled into a dilute liquid crystal to be used as a weak-alignment media in solution NMR structure determination of membrane proteins.
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Affiliation(s)
- John Min
- Department of Genetics, Harvard Medical School, Boston, MA, 02115, USA
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, 02115, USA
- Sculpting Evolution Group, Media Lab, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - William M Shih
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, 02115, USA
- Department of Cancer Biology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, 02115, USA
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, 02115, USA
| | - Gaëtan Bellot
- Institut de Génomique Fonctionnelle, Centre National de la Recherche Scientifique, CNRS Unité Mixte de Recherche UMR 5203, Institut National de la Santé et de la Recherche Médicale, INSERM U1191, Montpellier, 34000, France.
- Université de Montpellier, Montpellier, 34000, France.
- Institut de Génomique Fonctionnelle, 141 rue de la Cardonille, Montpellier, Cedex 5, 34094, France.
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35
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Moskalenko YE, Bagutski V, Thiele CM. Chemically synthesized and cross-linked PDMS as versatile alignment medium for organic compounds. Chem Commun (Camb) 2017; 53:95-98. [DOI: 10.1039/c6cc08762k] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Synthesis of PDMS gels with controlled amount of cross-linker opens up the opportunity for tuning of alignment media for RDC structure elucidation of organic molecules and mixtures of their isomers.
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Affiliation(s)
- Yulia E. Moskalenko
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie
- Technische Unitersität Darmstadt
- 64287 Darmstadt
- Germany
| | - Viktor Bagutski
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie
- Technische Unitersität Darmstadt
- 64287 Darmstadt
- Germany
| | - Christina M. Thiele
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie
- Technische Unitersität Darmstadt
- 64287 Darmstadt
- Germany
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36
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Schmidts V. Perspectives in the application of residual dipolar couplings in the structure elucidation of weakly aligned small molecules. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2017; 55:54-60. [PMID: 27743456 DOI: 10.1002/mrc.4543] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 10/10/2016] [Accepted: 10/13/2016] [Indexed: 05/28/2023]
Abstract
This perspective article aims to review the general methodology in the application of residual dipolar couplings (RDCs) in the structure elucidation of small molecules and give the author's view on challenges for future applications. Recent improvements in the availability of alignment media, new pulse sequences for the measurement of couplings and improvements in the analysis software have garnered widespread interest in the technique. However, further generalization is needed in order to make RDC analysis into a truly "routine" method. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Volker Schmidts
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Darmstadt, Germany
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37
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Abstract
It is well-established that dynamics are central to protein function; their importance is implicitly acknowledged in the principles of the Monod, Wyman and Changeux model of binding cooperativity, which was originally proposed in 1965. Nowadays the concept of protein dynamics is formulated in terms of the energy landscape theory, which can be used to understand protein folding and conformational changes in proteins. Because protein dynamics are so important, a key to understanding protein function at the molecular level is to design experiments that allow their quantitative analysis. Nuclear magnetic resonance (NMR) spectroscopy is uniquely suited for this purpose because major advances in theory, hardware, and experimental methods have made it possible to characterize protein dynamics at an unprecedented level of detail. Unique features of NMR include the ability to quantify dynamics (i) under equilibrium conditions without external perturbations, (ii) using many probes simultaneously, and (iii) over large time intervals. Here we review NMR techniques for quantifying protein dynamics on fast (ps-ns), slow (μs-ms), and very slow (s-min) time scales. These techniques are discussed with reference to some major discoveries in protein science that have been made possible by NMR spectroscopy.
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38
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Al‐Massaedh “AA, Schmidt M, Pyell U, Reinscheid UM. Elucidation of the Enantiodiscrimination Properties of a Nonracemic Chiral Alignment Medium through Gel-based Capillary Electrochromatography: Separation of the Mefloquine Stereoisomers. ChemistryOpen 2016; 5:455-459. [PMID: 27777838 PMCID: PMC5062011 DOI: 10.1002/open.201600085] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Indexed: 11/07/2022] Open
Abstract
Enantiodiscrimination and enantioseparation are two highly important processes in chemistry, often performed by using NMR spectroscopy and chromatography. For a better understanding of the mechanistic details, the same system should be studied by both methods. In addition, isotropic and anisotropic NMR parameters should be obtained, the latter using alignment media so that residual dipolar couplings and chemical-shift anisotropies can be measured. Consequently, a chiral alignment medium was used for the first time in chiral gel-based capillary electrochromatography with the four stereoisomers of the antimalaria drug mefloquine as test compounds. Chromatographic data verify that enantiodiscrimination obtained with this alignment gel is caused by differences in the equilibrium constants related to associate formation. Hence, the chromatographic separation provides physicochemical data that form a basis for the understanding and optimization of alignment processes, and vice versa.
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Affiliation(s)
- “Ayat Allah” Al‐Massaedh
- Department of ChemistryUniversity of MarburgHans-Meerwein-Straße35032MarburgGermany
- Department of ChemistryFaculty of ScienceAl al-Bayt University25113MafraqJordan
| | - Manuel Schmidt
- Department of NMR-based Structural BiologyMax-Planck-Institute for Biophysical ChemistryAm Fassberg 1137077GöttingenGermany
| | - Ute Pyell
- Department of ChemistryUniversity of MarburgHans-Meerwein-Straße35032MarburgGermany
| | - Uwe M. Reinscheid
- Department of NMR-based Structural BiologyMax-Planck-Institute for Biophysical ChemistryAm Fassberg 1137077GöttingenGermany
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39
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Nath N, Schmidt M, Gil RR, Williamson RT, Martin GE, Navarro-Vázquez A, Griesinger C, Liu Y. Determination of Relative Configuration from Residual Chemical Shift Anisotropy. J Am Chem Soc 2016; 138:9548-56. [DOI: 10.1021/jacs.6b04082] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Nilamoni Nath
- Department
of NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
| | - Manuel Schmidt
- Department
of NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
| | - Roberto R. Gil
- Department
of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - R. Thomas Williamson
- Process Research and Development, NMR Structure Elucidation Group, Merck & Co., Inc., 126 E Lincoln Avenue, Rahway, New Jersey 07065, United States
| | - Gary E. Martin
- Process Research and Development, NMR Structure Elucidation Group, Merck & Co., Inc., 126 E Lincoln Avenue, Rahway, New Jersey 07065, United States
| | - Armando Navarro-Vázquez
- Departamento
de Química Fundamental, Universidade Federal de Pernambuco, Cidade Universitária, Recife, PE 50740-560, Brazil
- Institute
of Organic Chemistry and Institute for Biological Interfaces Karlsruhe, Institute of Technology (KIT), Fritz-Haber-Weg 6, 76131 Karlsruhe, Germany
| | - Christian Griesinger
- Department
of NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
| | - Yizhou Liu
- Process Research and Development, NMR Structure Elucidation Group, Merck & Co., Inc., 126 E Lincoln Avenue, Rahway, New Jersey 07065, United States
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40
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Venditti V, Egner TK, Clore GM. Hybrid Approaches to Structural Characterization of Conformational Ensembles of Complex Macromolecular Systems Combining NMR Residual Dipolar Couplings and Solution X-ray Scattering. Chem Rev 2016; 116:6305-22. [PMID: 26739383 PMCID: PMC5590664 DOI: 10.1021/acs.chemrev.5b00592] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Solving structures or structural ensembles of large macromolecular systems in solution poses a challenging problem. While NMR provides structural information at atomic resolution, increased spectral complexity, chemical shift overlap, and short transverse relaxation times (associated with slow tumbling) render application of the usual techniques that have been so successful for medium sized systems (<50 kDa) difficult. Solution X-ray scattering, on the other hand, is not limited by molecular weight but only provides low resolution structural information related to the overall shape and size of the system under investigation. Here we review how combining atomic resolution structures of smaller domains with sparse experimental data afforded by NMR residual dipolar couplings (which yield both orientational and shape information) and solution X-ray scattering data in rigid-body simulated annealing calculations provides a powerful approach for investigating the structural aspects of conformational dynamics in large multidomain proteins. The application of this hybrid methodology is illustrated for the 128 kDa dimer of bacterial Enzyme I which exists in a variety of open and closed states that are sampled at various points in the catalytic cycles, and for the capsid protein of the human immunodeficiency virus.
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Affiliation(s)
- Vincenzo Venditti
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa 50011, United States
| | - Timothy K. Egner
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
| | - G. Marius Clore
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0520, United States
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41
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Di Pietro ME, Celebre G, De Luca G. Doped ionic liquid crystals as effective weakly alignment media for polar solutes. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 267:63-67. [PMID: 27128198 DOI: 10.1016/j.jmr.2016.04.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 04/19/2016] [Accepted: 04/20/2016] [Indexed: 06/05/2023]
Abstract
The ionic liquid crystal 1-dodecyl-3-methylimidazolium tetrafluoroborate slightly doped with water is presented as a promising NMR alignment medium for the measurement of residual dipolar couplings for polar molecules dissolved therein.
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Affiliation(s)
- Maria Enrica Di Pietro
- Lab. LXNMR_S.C.An., Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, via P. Bucci, 87036 Arcavacata di Rende (CS), Italy.
| | - Giorgio Celebre
- Lab. LXNMR_S.C.An., Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, via P. Bucci, 87036 Arcavacata di Rende (CS), Italy
| | - Giuseppina De Luca
- Lab. LXNMR_S.C.An., Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, via P. Bucci, 87036 Arcavacata di Rende (CS), Italy
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42
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Characterization of the conformational fluctuations in the Josephin domain of ataxin-3. Biophys J 2016; 107:2932-2940. [PMID: 25517158 PMCID: PMC4269769 DOI: 10.1016/j.bpj.2014.10.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Revised: 10/10/2014] [Accepted: 10/10/2014] [Indexed: 11/24/2022] Open
Abstract
As for a variety of other molecular recognition processes, conformational fluctuations play an important role in the cleavage of polyubiquitin chains by the Josephin domain of ataxin-3. The interaction between Josephin and ubiquitin appears to be mediated by the motions of α-helical hairpin that is unusual among deubiquitinating enzymes. Here, we characterized the conformational fluctuations of the helical hairpin by incorporating NMR measurements as replica-averaged restraints in molecular dynamics simulations, and by validating the results by small-angle x-ray scattering measurements. This approach allowed us to define the extent of the helical hairpin motions and suggest a role of such motions in the recognition of ubiquitin.
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43
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Vavrinská A, Zelinka J, Šebera J, Sychrovský V, Fiala R, Boelens R, Sklenář V, Trantírek L. Impact of nucleic acid self-alignment in a strong magnetic field on the interpretation of indirect spin-spin interactions. JOURNAL OF BIOMOLECULAR NMR 2016; 64:53-62. [PMID: 26685997 PMCID: PMC4742510 DOI: 10.1007/s10858-015-0005-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 12/06/2015] [Indexed: 06/05/2023]
Abstract
Heteronuclear and homonuclear direct (D) and indirect (J) spin-spin interactions are important sources of structural information about nucleic acids (NAs). The Hamiltonians for the D and J interactions have the same functional form; thus, the experimentally measured apparent spin-spin coupling constant corresponds to a sum of J and D. In biomolecular NMR studies, it is commonly presumed that the dipolar contributions to Js are effectively canceled due to random molecular tumbling. However, in strong magnetic fields, such as those employed for NMR analysis, the tumbling of NA fragments is anisotropic because the inherent magnetic susceptibility of NAs causes an interaction with the external magnetic field. This motional anisotropy is responsible for non-zero D contributions to Js. Here, we calculated the field-induced D contributions to 33 structurally relevant scalar coupling constants as a function of magnetic field strength, temperature and NA fragment size. We identified two classes of Js, namely (1)JCH and (3)JHH couplings, whose quantitative interpretation is notably biased by NA motional anisotropy. For these couplings, the magnetic field-induced dipolar contributions were found to exceed the typical experimental error in J-coupling determinations by a factor of two or more and to produce considerable over- or under-estimations of the J coupling-related torsion angles, especially at magnetic field strengths >12 T and for NA fragments longer than 12 bp. We show that if the non-zero D contributions to J are not properly accounted for, they might cause structural artifacts/bias in NA studies that use solution NMR spectroscopy.
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Affiliation(s)
- Andrea Vavrinská
- Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Jiří Zelinka
- Faculty of Science, Masaryk University, Kotlářská 2, 611 37, Brno, Czech Republic
| | - Jakub Šebera
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo náměstí 542/2, 166 10, Praha 6, Czech Republic
- Institute of Physics, Academy of Sciences of the Czech Republic, v.v.i, Na Slovance 2, 182 21, Prague 8, Czech Republic
| | - Vladimír Sychrovský
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo náměstí 542/2, 166 10, Praha 6, Czech Republic
| | - Radovan Fiala
- Central European Institute of Technology, Masaryk University, Kamenice 753/5, 625 00, Brno, Czech Republic
| | - Rolf Boelens
- Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Vladimír Sklenář
- Central European Institute of Technology, Masaryk University, Kamenice 753/5, 625 00, Brno, Czech Republic
| | - Lukáš Trantírek
- Central European Institute of Technology, Masaryk University, Kamenice 753/5, 625 00, Brno, Czech Republic.
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44
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Measurement, Interpretation and Use of Free Ligand Solution Conformations in Drug Discovery. PROGRESS IN MEDICINAL CHEMISTRY 2016; 55:45-147. [DOI: 10.1016/bs.pmch.2015.10.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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45
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Gil-Silva LF, Santamaría-Fernández R, Navarro-Vázquez A, Gil RR. Collection of NMR Scalar and Residual Dipolar Couplings Using a Single Experiment. Chemistry 2015; 22:472-6. [DOI: 10.1002/chem.201503449] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2015] [Indexed: 11/11/2022]
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46
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Salmon L, Blackledge M. Investigating protein conformational energy landscapes and atomic resolution dynamics from NMR dipolar couplings: a review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2015; 78:126601. [PMID: 26517337 DOI: 10.1088/0034-4885/78/12/126601] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Nuclear magnetic resonance spectroscopy is exquisitely sensitive to protein dynamics. In particular inter-nuclear dipolar couplings, that become measurable in solution when the protein is dissolved in a dilute liquid crystalline solution, report on all conformations sampled up to millisecond timescales. As such they provide the opportunity to describe the Boltzmann distribution present in solution at atomic resolution, and thereby to map the conformational energy landscape in unprecedented detail. The development of analytical methods and approaches based on numerical simulation and their application to numerous biologically important systems is presented.
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Affiliation(s)
- Loïc Salmon
- Université Grenoble Alpes, Institut de Biologie Structurale (IBS), F-38027 Grenoble, France. CEA, DSV, IBS, F-38027 Grenoble, France. CNRS, IBS, F-38027 Grenoble, France
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47
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Takeuchi K, Arthanari H, Shimada I, Wagner G. Nitrogen detected TROSY at high field yields high resolution and sensitivity for protein NMR. JOURNAL OF BIOMOLECULAR NMR 2015; 63:323-331. [PMID: 26497830 PMCID: PMC4749451 DOI: 10.1007/s10858-015-9991-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2015] [Accepted: 10/01/2015] [Indexed: 05/18/2023]
Abstract
Detection of (15)N in multidimensional NMR experiments of proteins has sparsely been utilized because of the low gyromagnetic ratio (γ) of nitrogen and the presumed low sensitivity of such experiments. Here we show that selecting the TROSY components of proton-attached (15)N nuclei (TROSY (15)NH) yields high quality spectra in high field magnets (>600 MHz) by taking advantage of the slow (15)N transverse relaxation and compensating for the inherently low (15)N sensitivity. The (15)N TROSY transverse relaxation rates increase modestly with molecular weight but the TROSY gain in peak heights depends strongly on the magnetic field strength. Theoretical simulations predict that the narrowest line width for the TROSY (15)NH component can be obtained at 900 MHz, but sensitivity reaches its maximum around 1.2 GHz. Based on these considerations, a (15)N-detected 2D (1)H-(15)N TROSY-HSQC ((15)N-detected TROSY-HSQC) experiment was developed and high-quality 2D spectra were recorded at 800 MHz in 2 h for 1 mM maltose-binding protein at 278 K (τc ~ 40 ns). Unlike for (1)H detected TROSY, deuteration is not mandatory to benefit (15)N detected TROSY due to reduced dipolar broadening, which facilitates studies of proteins that cannot be deuterated, especially in cases where production requires eukaryotic expression systems. The option of recording (15)N TROSY of proteins expressed in H2O media also alleviates the problem of incomplete amide proton back exchange, which often hampers the detection of amide groups in the core of large molecular weight proteins that are expressed in D2O culture media and cannot be refolded for amide back exchange. These results illustrate the potential of (15)NH-detected TROSY experiments as a means to exploit the high resolution offered by high field magnets near and above 1 GHz.
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Affiliation(s)
- Koh Takeuchi
- Molecular Profiling Research Center for Drug Discovery, National Institute for Advanced Industrial Science and Technology, Tokyo, 135-0063, Japan
- PRESTO, JST, Tokyo, 135-0063, Japan
| | - Haribabu Arthanari
- Department of Biochemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, MA, 02115, USA
| | - Ichio Shimada
- Molecular Profiling Research Center for Drug Discovery, National Institute for Advanced Industrial Science and Technology, Tokyo, 135-0063, Japan.
- Graduate Schools of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
| | - Gerhard Wagner
- Department of Biochemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, MA, 02115, USA.
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Martin RW, Kelly JE, Collier KA. Spatial reorientation experiments for NMR of solids and partially oriented liquids. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2015; 90-91:92-122. [PMID: 26592947 PMCID: PMC6936739 DOI: 10.1016/j.pnmrs.2015.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2015] [Revised: 10/13/2015] [Accepted: 10/15/2015] [Indexed: 06/05/2023]
Abstract
Motional reorientation experiments are extensions of Magic Angle Spinning (MAS) where the rotor axis is changed in order to average out, reintroduce, or scale anisotropic interactions (e.g. dipolar couplings, quadrupolar interactions or chemical shift anisotropies). This review focuses on Variable Angle Spinning (VAS), Switched Angle Spinning (SAS), and Dynamic Angle Spinning (DAS), all of which involve spinning at two or more different angles sequentially, either in successive experiments or during a multidimensional experiment. In all of these experiments, anisotropic terms in the Hamiltonian are scaled by changing the orientation of the spinning sample relative to the static magnetic field. These experiments vary in experimental complexity and instrumentation requirements. In VAS, many one-dimensional spectra are collected as a function of spinning angle. In SAS, dipolar couplings and/or chemical shift anisotropies are reintroduced by switching the sample between two different angles, often 0° or 90° and the magic angle, yielding a two-dimensional isotropic-anisotropic correlation spectrum. Dynamic Angle Spinning (DAS) is a related experiment that is used to simultaneously average out the first- and second-order quadrupolar interactions, which cannot be accomplished by spinning at any unique rotor angle in physical space. Although motional reorientation experiments generally require specialized instrumentation and data analysis schemes, some are accessible with only minor modification of standard MAS probes. In this review, the mechanics of each type of experiment are described, with representative examples. Current and historical probe and coil designs are discussed from the standpoint of how each one accomplishes the particular objectives of the experiment(s) it was designed to perform. Finally, applications to inorganic materials and liquid crystals, which present very different experimental challenges, are discussed. The review concludes with perspectives on how motional reorientation experiments can be applied to current problems in chemistry, molecular biology, and materials science, given the many advances in high-field NMR magnets, fast spinning, and sample preparation realized in recent years.
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Affiliation(s)
- Rachel W Martin
- Department of Chemistry, University of California, Irvine 92697-2025, United States; Department of Molecular Biology and Biochemistry, University of California, Irvine 92697-3900, United States.
| | - John E Kelly
- Department of Chemistry, University of California, Irvine 92697-2025, United States
| | - Kelsey A Collier
- Department of Physics and Astronomy, University of California, Irvine 92697-4575, United States
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Naumann C, Kuchel PW. NMR Spectra of Glycine Isotopomers in Anisotropic Media: Subtle Chiral Interactions. Anal Chem 2015; 87:10437-42. [PMID: 26430874 DOI: 10.1021/acs.analchem.5b02542] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
NMR spectra of deuterated glycine-2-(13)C revealed interactions between chiral anisotropic gelatin and κ-carrageenan gels and the prochiral and chiral isotopomers. The (1)H, (2)H and (13)C NMR spectra of mixtures of racemic mono- and prochiral bis-deuterated glycine-2-(13)C were resolved and well simulated using distinct dipolar coupling constants DCαH and DCαD for the enantiomers and also for the -(13)CαD2- group (DC,DA, and DC,DB). The orientation of the proton or deuteron on the (13)Cα-atom of glycine was assigned by analogy with alanine and lactate assuming that the molecular orientation of glycine isotopomers is the same. The assignment of the prochiral sites was derived from chiral analogues.
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Affiliation(s)
- Christoph Naumann
- School of Molecular Bioscience University of Sydney , Sydney, New South Wales 2006, Australia
| | - Philip W Kuchel
- School of Molecular Bioscience University of Sydney , Sydney, New South Wales 2006, Australia
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Niklas T, Steinmetzger C, Liu W, Zell D, Stalke D, Ackermann L, John M. Determination of the Relative Configuration of β-Amino Acid Esters Based on Residual Dipolar Couplings. European J Org Chem 2015. [DOI: 10.1002/ejoc.201500941] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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