101
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Bahramzadeh A, Jiang H, Huber T, Otting G. Two Histidines in an α‐Helix: A Rigid Co
2+
‐Binding Motif for PCS Measurements by NMR Spectroscopy. Angew Chem Int Ed Engl 2018; 57:6226-6229. [DOI: 10.1002/anie.201802501] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Indexed: 01/26/2023]
Affiliation(s)
- Alireza Bahramzadeh
- Research School of Chemistry The Australian National University Canberra ACT 2601 Australia
| | - Hailun Jiang
- Research School of Chemistry The Australian National University Canberra ACT 2601 Australia
| | - Thomas Huber
- Research School of Chemistry The Australian National University Canberra ACT 2601 Australia
| | - Gottfried Otting
- Research School of Chemistry The Australian National University Canberra ACT 2601 Australia
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102
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Capturing dynamic conformational shifts in protein–ligand recognition using integrative structural biology in solution. Emerg Top Life Sci 2018; 2:107-119. [DOI: 10.1042/etls20170090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 03/18/2018] [Accepted: 03/20/2018] [Indexed: 11/17/2022]
Abstract
In recent years, a dynamic view of the structure and function of biological macromolecules is emerging, highlighting an essential role of dynamic conformational equilibria to understand molecular mechanisms of biological functions. The structure of a biomolecule, i.e. protein or nucleic acid in solution, is often best described as a dynamic ensemble of conformations, rather than a single structural state. Strikingly, the molecular interactions and functions of the biological macromolecule can then involve a shift between conformations that pre-exist in such an ensemble. Upon external cues, such population shifts of pre-existing conformations allow gradually relaying the signal to the downstream biological events. An inherent feature of this principle is conformational dynamics, where intrinsically disordered regions often play important roles to modulate the conformational ensemble. Unequivocally, solution-state NMR spectroscopy is a powerful technique to study the structure and dynamics of such biomolecules in solution. NMR is increasingly combined with complementary techniques, including fluorescence spectroscopy and small angle scattering. The combination of these techniques provides complementary information about the conformation and dynamics in solution and thus affords a comprehensive description of biomolecular functions and regulations. Here, we illustrate how an integrated approach combining complementary techniques can assess the structure and dynamics of proteins and protein complexes in solution.
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103
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Prokopiou G, Lee MD, Collauto A, Abdelkader EH, Bahrenberg T, Feintuch A, Ramirez-Cohen M, Clayton J, Swarbrick JD, Graham B, Otting G, Goldfarb D. Small Gd(III) Tags for Gd(III)–Gd(III) Distance Measurements in Proteins by EPR Spectroscopy. Inorg Chem 2018; 57:5048-5059. [DOI: 10.1021/acs.inorgchem.8b00133] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Georgia Prokopiou
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Michael D. Lee
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
| | - Alberto Collauto
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Elwy H. Abdelkader
- Research School of Chemistry, Australian National University, Canberra, ACT 2601,Australia
| | - Thorsten Bahrenberg
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Akiva Feintuch
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Marie Ramirez-Cohen
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Jessica Clayton
- Department of Physics, University of California, Santa Barbara, California 93106-9530, United States
| | - James D. Swarbrick
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
| | - Bim Graham
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
| | - Gottfried Otting
- Research School of Chemistry, Australian National University, Canberra, ACT 2601,Australia
| | - Daniella Goldfarb
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel
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104
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Hoffmann B, Löhr F, Laguerre A, Bernhard F, Dötsch V. Protein labeling strategies for liquid-state NMR spectroscopy using cell-free synthesis. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2018; 105:1-22. [PMID: 29548364 DOI: 10.1016/j.pnmrs.2017.11.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 11/16/2017] [Indexed: 05/17/2023]
Abstract
Preparation of a protein sample for liquid-state nuclear magnetic resonance (NMR) spectroscopy analysis requires optimization of many parameters. This review describes labeling strategies for obtaining assignments of protein resonances. Particular emphasis is placed on the advantages of cell-free protein production, which enables exclusive labeling of the protein of interest, thereby simplifying downstream processing steps and increasing the availability of different labeling strategies for a target protein. Furthermore, proteins can be synthesized in milligram yields, and the open nature of the cell-free system allows the addition of stabilizers, scrambling inhibitors or hydrophobic solubilization environments directly during the protein synthesis, which is especially beneficial for membrane proteins. Selective amino acid labeling of the protein of interest, the possibility of addressing scrambling issues and avoiding the need for labile amino acid precursors have been key factors in enabling the introduction of new assignment strategies based on different labeling schemes as well as on new pulse sequences. Combinatorial selective labeling methods have been developed to reduce the number of protein samples necessary to achieve a complete backbone assignment. Furthermore, selective labeling helps to decrease spectral overlap and overcome size limitations for solution NMR analysis of larger complexes, oligomers, intrinsically disordered proteins and membrane proteins.
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Affiliation(s)
- Beate Hoffmann
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Max-von-Laue Str. 9, 60438 Frankfurt, Germany
| | - Frank Löhr
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Max-von-Laue Str. 9, 60438 Frankfurt, Germany
| | - Aisha Laguerre
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Max-von-Laue Str. 9, 60438 Frankfurt, Germany
| | - Frank Bernhard
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Max-von-Laue Str. 9, 60438 Frankfurt, Germany
| | - Volker Dötsch
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Max-von-Laue Str. 9, 60438 Frankfurt, Germany.
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105
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Lee MD, Dennis ML, Graham B, Swarbrick JD. Short two-armed lanthanide-binding tags for paramagnetic NMR spectroscopy based on chiral 1,4,7,10-tetrakis(2-hydroxypropyl)-1,4,7,10-tetraazacyclododecane scaffolds. Chem Commun (Camb) 2018; 53:13205-13208. [PMID: 29165449 DOI: 10.1039/c7cc07961c] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
A new pair of enantiomeric two-armed lanthanide-binding tags have been developed for paramagnetic NMR studies of proteins. The tags produce large and significantly different paramagnetic effects to one another when bound to the same tagging site. Additionally, they are less sensitive to sample pH than our previous two-armed tag designs.
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Affiliation(s)
- Michael D Lee
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville VIC 3052, Australia.
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106
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Paramagnetic NMR as a new tool in structural biology. Emerg Top Life Sci 2018; 2:19-28. [DOI: 10.1042/etls20170084] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2017] [Revised: 12/19/2017] [Accepted: 12/20/2017] [Indexed: 12/25/2022]
Abstract
NMR (nuclear magnetic resonance) investigation through the exploitation of paramagnetic effects is passing from an approach limited to few specialists in the field to a generally applicable method that must be considered, especially for the characterization of systems hardly affordable with other techniques. This is mostly due to the fact that paramagnetic data are long range in nature, thus providing information for the structural and dynamic characterization of complex biomolecular architectures in their native environment. On the other hand, this information usually needs to be complemented by data from other sources. Integration of paramagnetic NMR with other techniques, and the development of protocols for a joint analysis of all available data, is fundamental for achieving a comprehensive characterization of complex biological systems. We describe here a few examples of the new possibilities offered by paramagnetic data used in integrated structural approaches.
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107
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Grytz CM, Kazemi S, Marko A, Cekan P, Güntert P, Sigurdsson ST, Prisner TF. Determination of helix orientations in a flexible DNA by multi-frequency EPR spectroscopy. Phys Chem Chem Phys 2018; 19:29801-29811. [PMID: 29090294 DOI: 10.1039/c7cp04997h] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Distance measurements are performed between a pair of spin labels attached to nucleic acids using Pulsed Electron-Electron Double Resonance (PELDOR, also called DEER) spectroscopy which is a complementary tool to other structure determination methods in structural biology. The rigid spin label Ç, when incorporated pairwise into two helical parts of a nucleic acid molecule, allows the determination of both the mutual orientation and the distance between those labels, since Ç moves rigidly with the helix to which it is attached. We have developed a two-step protocol to investigate the conformational flexibility of flexible nucleic acid molecules by multi-frequency PELDOR. In the first step, a library with a broad collection of conformers, which are in agreement with topological constraints, NMR restraints and distances derived from PELDOR, was created. In the second step, a weighted structural ensemble of these conformers was chosen, such that it fits the multi-frequency PELDOR time traces of all doubly Ç-labelled samples simultaneously. This ensemble reflects the global structure and the conformational flexibility of the two-way DNA junction. We demonstrate this approach on a flexible bent DNA molecule, consisting of two short helical parts with a five adenine bulge at the center. The kink and twist motions between both helical parts were quantitatively determined and showed high flexibility, in agreement with a Förster Resonance Energy Transfer (FRET) study on a similar bent DNA motif. The approach presented here should be useful to describe the relative orientation of helical motifs and the conformational flexibility of nucleic acid structures, both alone and in complexes with proteins and other molecules.
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Affiliation(s)
- C M Grytz
- Institute of Physical and Theoretical Chemistry, Goethe University, Max-von-Laue-Str. 7, 60438 Frankfurt am Main, Germany.
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108
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Chen JL, Zhao Y, Gong YJ, Pan BB, Wang X, Su XC. Stable and rigid DTPA-like paramagnetic tags suitable for in vitro and in situ protein NMR analysis. JOURNAL OF BIOMOLECULAR NMR 2018; 70:77-92. [PMID: 29224182 DOI: 10.1007/s10858-017-0160-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 12/05/2017] [Indexed: 06/07/2023]
Abstract
Organic synthesis of a ligand with high binding affinities for paramagnetic lanthanide ions is an effective way of generating paramagnetic effects on proteins. These paramagnetic effects manifested in high-resolution NMR spectroscopy are valuable dynamic and structural restraints of proteins and protein-ligand complexes. A paramagnetic tag generally contains a metal chelating moiety and a reactive group for protein modification. Herein we report two new DTPA-like tags, 4PS-PyDTTA and 4PS-6M-PyDTTA that can be site-specifically attached to a protein with a stable thioether bond. Both protein-tag adducts form stable lanthanide complexes, of which the binding affinities and paramagnetic tensors are tunable with respect to the 6-methyl group in pyridine. Paramagnetic relaxation enhancement (PRE) effects of Gd(III) complex on protein-tag adducts were evaluated in comparison with pseudocontact shift (PCS), and the results indicated that both 4PS-PyDTTA and 4PS-6M-PyDTTA tags are rigid and present high-quality PREs that are crucially important in elucidation of the dynamics and interactions of proteins and protein-ligand complexes. We also show that these two tags are suitable for in-situ protein NMR analysis.
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Affiliation(s)
- Jia-Liang Chen
- State Key Laboratory of Elemento-Organic Chemistry and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Yu Zhao
- State Key Laboratory of Elemento-Organic Chemistry and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Yan-Jun Gong
- State Key Laboratory of Elemento-Organic Chemistry and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Bin-Bin Pan
- State Key Laboratory of Elemento-Organic Chemistry and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Xiao Wang
- State Key Laboratory of Elemento-Organic Chemistry and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Xun-Cheng Su
- State Key Laboratory of Elemento-Organic Chemistry and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), College of Chemistry, Nankai University, Tianjin, 300071, China.
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109
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Nitsche C, Otting G. NMR studies of ligand binding. Curr Opin Struct Biol 2017; 48:16-22. [PMID: 29017071 DOI: 10.1016/j.sbi.2017.09.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 09/15/2017] [Accepted: 09/18/2017] [Indexed: 12/17/2022]
Abstract
NMR spectroscopy is an established tool in drug discovery, but its strength is commonly regarded to be largely confined to the early stages of hit discovery and fragment based drug design, where NMR offers unique capabilities of characterizing the binding modes of ligand molecules that bind sufficiently weakly to be in rapid exchange between bound and free state. Here we, first, provide a meta-review of recent reviews on NMR studies of ligand binding and, second, review recent progress towards NMR characterization of the ligand binding mode in stable protein-ligand complexes, with particular emphasis on the global positioning system (GPS) approach enabled by paramagnetic lanthanide tags.
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Affiliation(s)
- Christoph Nitsche
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Gottfried Otting
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia.
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110
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Ravera E, Parigi G, Luchinat C. Perspectives on paramagnetic NMR from a life sciences infrastructure. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2017; 282:154-169. [PMID: 28844254 DOI: 10.1016/j.jmr.2017.07.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 07/28/2017] [Accepted: 07/31/2017] [Indexed: 05/17/2023]
Abstract
The effects arising in NMR spectroscopy because of the presence of unpaired electrons, collectively referred to as "paramagnetic NMR" have attracted increasing attention over the last decades. From the standpoint of the structural and mechanistic biology, paramagnetic NMR provides long range restraints that can be used to assess the accuracy of crystal structures in solution and to improve them by simultaneous refinements through NMR and X-ray data. These restraints also provide information on structure rearrangements and conformational variability in biomolecular systems. Theoretical improvements in quantum chemistry calculations can nowadays allow for accurate calculations of the paramagnetic data from a molecular structural model, thus providing a tool to refine the metal coordination environment by matching the paramagnetic effects observed far away from the metal. Furthermore, the availability of an improved technology (higher fields and faster magic angle spinning) has promoted paramagnetic NMR applications in the fast-growing area of biomolecular solid-state NMR. Major improvements in dynamic nuclear polarization have been recently achieved, especially through the exploitation of the Overhauser effect occurring through the contact-driven relaxation mechanism: the very large enhancement of the 13C signal observed in a variety of liquid organic compounds at high fields is expected to open up new perspectives for applications of solution NMR.
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Affiliation(s)
- Enrico Ravera
- Magnetic Resonance Center (CERM) and Department of Chemistry "Ugo Schiff", University of Florence, via Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Giacomo Parigi
- Magnetic Resonance Center (CERM) and Department of Chemistry "Ugo Schiff", University of Florence, via Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM) and Department of Chemistry "Ugo Schiff", University of Florence, via Sacconi 6, 50019 Sesto Fiorentino, Italy.
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111
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Pilla KB, Gaalswyk K, MacCallum JL. Molecular modeling of biomolecules by paramagnetic NMR and computational hybrid methods. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2017. [PMID: 28648524 DOI: 10.1016/j.bbapap.2017.06.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The 3D atomic structures of biomolecules and their complexes are key to our understanding of biomolecular function, recognition, and mechanism. However, it is often difficult to obtain structures, particularly for systems that are complex, dynamic, disordered, or exist in environments like cell membranes. In such cases sparse data from a variety of paramagnetic NMR experiments offers one possible source of structural information. These restraints can be incorporated in computer modeling algorithms that can accurately translate the sparse experimental data into full 3D atomic structures. In this review, we discuss various types of paramagnetic NMR/computational hybrid modeling techniques that can be applied to successful modeling of not only the atomic structure of proteins but also their interacting partners. This article is part of a Special Issue entitled: Biophysics in Canada, edited by Lewis Kay, John Baenziger, Albert Berghuis and Peter Tieleman.
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Affiliation(s)
| | - Kari Gaalswyk
- Department of Chemistry, University of Calgary, Calgary, AB, Canada
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112
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Mahawaththa MC, Pearce BJ, Szabo M, Graham B, Klein CD, Nitsche C, Otting G. Solution conformations of a linked construct of the Zika virus NS2B-NS3 protease. Antiviral Res 2017; 142:141-147. [DOI: 10.1016/j.antiviral.2017.03.011] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2017] [Revised: 03/14/2017] [Accepted: 03/18/2017] [Indexed: 01/28/2023]
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113
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Wu Z, Lee MD, Carruthers TJ, Szabo M, Dennis ML, Swarbrick JD, Graham B, Otting G. New Lanthanide Tag for the Generation of Pseudocontact Shifts in DNA by Site-Specific Ligation to a Phosphorothioate Group. Bioconjug Chem 2017; 28:1741-1748. [PMID: 28485576 DOI: 10.1021/acs.bioconjchem.7b00202] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Pseudocontact shifts (PCS) generated by paramagnetic lanthanides provide a rich source of long-range structural restraints that can readily be measured by nuclear magnetic resonance (NMR) spectroscopy. Many different lanthanide-binding tags have been designed for site-specific tagging of proteins, but established routes for tagging DNA with a single metal ion rely on difficult chemical synthesis. Here we present a simple and practical strategy for site-specific tagging of inexpensive phosphorothioate (PT) oligonucleotides. Commercially available PT oligonucleotides are diastereomers with S and R stereoconfiguration at the backbone PT site. The respective SP and RP diastereomers can readily be separated by HPLC. A new alkylating lanthanide-binding tag, C10, was synthesized that delivered quantitative tagging yields with both diastereomers. PCSs were observed following ligation with the complementary DNA strand to form double-stranded DNA duplexes. The PCSs were larger for the SP than the RP oligonucleotide and good correlation between back-calculated and experimental PCSs was observed. The C10 tag can also be attached to cysteine residues in proteins, where it generates a stable thioether bond. Ligated to the A28C mutant of ubiquitin, the tag produced excellent fits of magnetic susceptibility anisotropy (Δχ) tensors, with larger tensors than for the tagged PT oligonucleotides, indicating that the tag is not completely immobilized after ligation with a PT group.
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Affiliation(s)
- Zuyan Wu
- Research School of Chemistry, Australian National University , Canberra, ACT 2601, Australia
| | - Michael D Lee
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University , Parkville, VIC 3052, Australia
| | - Thomas J Carruthers
- Research School of Chemistry, Australian National University , Canberra, ACT 2601, Australia
| | - Monika Szabo
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University , Parkville, VIC 3052, Australia
| | - Matthew L Dennis
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University , Parkville, VIC 3052, Australia
| | - James D Swarbrick
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University , Parkville, VIC 3052, Australia
| | - Bim Graham
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University , Parkville, VIC 3052, Australia
| | - Gottfried Otting
- Research School of Chemistry, Australian National University , Canberra, ACT 2601, Australia
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114
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Pearce BJG, Jabar S, Loh CT, Szabo M, Graham B, Otting G. Structure restraints from heteronuclear pseudocontact shifts generated by lanthanide tags at two different sites. JOURNAL OF BIOMOLECULAR NMR 2017; 68:19-32. [PMID: 28434103 DOI: 10.1007/s10858-017-0111-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 04/11/2017] [Indexed: 05/14/2023]
Abstract
Pseudocontact shifts (PCS) encode long-range information on 3D structures of protein backbones and side-chains. The level of structural detail that can be obtained increases with the number of different sites tagged with a paramagnetic metal ion to generate PCSs. Here we show that PCSs from two different sites can suffice to determine the structure of polypeptide chains and their location and orientation relative to the magnetic susceptibility tensor χ, provided that PCSs are available for 1H as well as heteronuclear spins. In addition, PCSs from two different sites are shown to provide detailed structural information on the conformation of methyl group-bearing amino-acid side-chains. A previously published ensemble structure of ubiquitin is shown to explain the magnetic susceptibility and alignment tensors slightly better than structures that try to explain the experimental data by a single conformation, illustrating the potential of PCSs as a tool to investigate small conformational changes.
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Affiliation(s)
- Benjamin J G Pearce
- Research School of Chemistry, Australian National University, Canberra, ACT, 2601, Australia
| | - Shereen Jabar
- Research School of Chemistry, Australian National University, Canberra, ACT, 2601, Australia
| | - Choy-Theng Loh
- Research School of Chemistry, Australian National University, Canberra, ACT, 2601, Australia
| | - Monika Szabo
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
| | - Bim Graham
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
| | - Gottfried Otting
- Research School of Chemistry, Australian National University, Canberra, ACT, 2601, Australia.
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115
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Nitsche C, Mahawaththa MC, Becker W, Huber T, Otting G. Site-selective tagging of proteins by pnictogen-mediated self-assembly. Chem Commun (Camb) 2017; 53:10894-10897. [DOI: 10.1039/c7cc06155b] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Trivalent pnictogens (Pn) enable the selective self-assembly between an engineered di-cysteine motif in a protein and a thiol-containing lanthanide (Ln) probe.
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Affiliation(s)
- Christoph Nitsche
- Research School of Chemistry
- Australian National University
- Canberra
- Australia
| | | | - Walter Becker
- Research School of Chemistry
- Australian National University
- Canberra
- Australia
| | - Thomas Huber
- Research School of Chemistry
- Australian National University
- Canberra
- Australia
| | - Gottfried Otting
- Research School of Chemistry
- Australian National University
- Canberra
- Australia
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