1
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Raum HN, Modig K, Akke M, Weininger U. Proton Transfer Kinetics in Histidine Side Chains Determined by pH-Dependent Multi-Nuclear NMR Relaxation. J Am Chem Soc 2024. [PMID: 39103163 DOI: 10.1021/jacs.4c04647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/07/2024]
Abstract
Histidine is a key amino-acid residue in proteins with unique properties engendered by its imidazole side chain that can exist in three different states: two different neutral tautomeric forms and a protonated, positively charged one with a pKa value close to physiological pH. Commonly, two or all three states coexist and interchange rapidly, enabling histidine to act as both donor and acceptor of hydrogen bonds, coordinate metal ions, and engage in acid/base catalysis. Understanding the exchange dynamics among the three states is critical for assessing histidine's mechanistic role in catalysis, where the rate of proton exchange and interconversion among tautomers might be rate limiting for turnover. Here, we determine the exchange kinetics of histidine residues with pKa values representative of the accessible range from 5 to 9 by measuring pH-dependent 15N, 13C, and 1H transverse relaxation rate constants for 5 nuclei in each imidazole. Proton exchange between the imidazole and the solvent is mediated by hydronium ions at acidic and neutral pH, whereas hydroxide mediated exchange becomes the dominant mechanism at basic pH. Proton transfer is very fast and reaches the diffusion limit for pKa values near neutral pH. We identify a direct pathway between the two tautomeric forms, likely mediated by a bridging water molecule or, in the case of high pH, hydroxide ion. For histidines with pKa 7, we determine all rate constants (lifetimes) involving protonation over the entire pH range. Our approach should enable critical insights into enzymatic acid/base catalyzed reactions involving histidines in proteins.
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Affiliation(s)
- Heiner N Raum
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, Halle (Saale) D-06120, Germany
| | - Kristofer Modig
- Division of Biophysical Chemistry, Center for Molecular Protein Science, Department of Chemistry, Lund University, P.O. Box 124, Lund SE-22100, Sweden
| | - Mikael Akke
- Division of Biophysical Chemistry, Center for Molecular Protein Science, Department of Chemistry, Lund University, P.O. Box 124, Lund SE-22100, Sweden
| | - Ulrich Weininger
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, Halle (Saale) D-06120, Germany
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2
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Raum HN, Fisher SZ, Weininger U. Energetics and dynamics of the proton shuttle of carbonic anhydrase II. Cell Mol Life Sci 2023; 80:286. [PMID: 37688664 PMCID: PMC10492700 DOI: 10.1007/s00018-023-04936-z] [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] [Received: 05/19/2023] [Revised: 07/26/2023] [Accepted: 08/23/2023] [Indexed: 09/11/2023]
Abstract
Human carbonic anhydrase II catalyzes the reversible reaction of carbon dioxide and water to form bicarbonate and a proton. His64-mediated proton shuttling between the active site and the bulk solvent is rate limiting. Here we investigate the protonation behavior of His64 as well as its structural and dynamic features in a pH dependent way. We derive two pKa values for His64, 6.25 and 7.60, that we were able to assign to its inward and outward conformation. Furthermore, we show that His64 exists in both conformations equally, independent of pH. Both conformations display an equal distribution of their two neutral tautomeric states. The life time of each conformation is short and both states display high flexibility within their orientation. Therefore, His64 is never static, but rather poised to change conformation. These findings support an energetic, dynamic and solution ensemble-based framework for the high enzymatic activity of human carbonic anhydrase II.
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Affiliation(s)
- Heiner N Raum
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Suzanne Zoë Fisher
- Department of Biology and Lund Protein Production Platform, Lund University, Sölvegatan 35, 22362, Lund, Sweden
- Scientific Activities Division, European Spallation Source ERIC, P.O. Box 176, 22100, Lund, Sweden
| | - Ulrich Weininger
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, 06120, Halle (Saale), Germany.
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3
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Dreydoppel M, Lichtenecker RJ, Akke M, Weininger U. 1H R 1ρ relaxation dispersion experiments in aromatic side chains. JOURNAL OF BIOMOLECULAR NMR 2021; 75:383-392. [PMID: 34510298 PMCID: PMC8642340 DOI: 10.1007/s10858-021-00382-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 09/03/2021] [Indexed: 06/13/2023]
Abstract
Aromatic side chains are attractive probes of protein dynamic, since they are often key residues in enzyme active sites and protein binding sites. Dynamic processes on microsecond to millisecond timescales can be studied by relaxation dispersion experiments that attenuate conformational exchange contributions to the transverse relaxation rate by varying the refocusing frequency of applied radio-frequency fields implemented as either CPMG pulse trains or continuous spin-lock periods. Here we present an aromatic 1H R1ρ relaxation dispersion experiment enabling studies of two to three times faster exchange processes than achievable by existing experiments for aromatic side chains. We show that site-specific isotope labeling schemes generating isolated 1H-13C spin pairs with vicinal 2H-12C moieties are necessary to avoid anomalous relaxation dispersion profiles caused by Hartmann-Hahn matching due to the 3JHH couplings and limited chemical shift differences among 1H spins in phenylalanine, tyrosine and the six-ring moiety of tryptophan. This labeling pattern is sufficient in that remote protons do not cause additional complications. We validated the approach by measuring ring-flip kinetics in the small protein GB1. The determined rate constants, kflip, agree well with previous results from 13C R1ρ relaxation dispersion experiments, and yield 1H chemical shift differences between the two sides of the ring in good agreement with values measured under slow-exchange conditions. The aromatic1H R1ρ relaxation dispersion experiment in combination with the site-selective 1H-13C/2H-12C labeling scheme enable measurement of exchange rates up to kex = 2kflip = 80,000 s-1, and serve as a useful complement to previously developed 13C-based methods.
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Affiliation(s)
- Matthias Dreydoppel
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | | | - Mikael Akke
- Division of Biophysical Chemistry, Center for Molecular Protein Science, Department of Chemistry, Lund University, P.O. Box 124, 22100, Lund, Sweden
| | - Ulrich Weininger
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, 06120, Halle (Saale), Germany.
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4
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Tong Q, Tan H, Li J, Xie H, Zhao Y, Chen Y, Yang J. Extensively sparse 13C labeling to simplify solid-state NMR 13C spectra of membrane proteins. JOURNAL OF BIOMOLECULAR NMR 2021; 75:245-254. [PMID: 34148188 DOI: 10.1007/s10858-021-00372-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Accepted: 06/08/2021] [Indexed: 06/12/2023]
Abstract
Solid-state Nuclear Magnetic Resonance (ssNMR) is an emerging technique to investigate the structures and dynamics of membrane proteins in an artificial or native membrane environment. However, the structural studies of proteins by ssNMR are usually prolonged or impeded by signal assignments, especially the assignments of signals for collection of distance restraints, because of serious overlapping of signals in 2D 13C-13C spectra. Sparse labeling of 13C spins is an effective approach to simplify the 13C spectra and facilitate the extractions of distance restraints. Here, we propose a new reverse labeling combination of six types of amino acid residues (Ile, Leu, Phe, Trp, Tyr and Lys), and show a clean reverse labeling effect on a model membrane protein E. coli aquaporin Z (AqpZ). We further combine this reverse labeling combination and alternate 13C-12C labeling, and demonstrate an enhanced dilution effect in 13C-13C spectra. In addition, the influences of reverse labeling on the labeling of the other types of residues are quantitatively analyzed in the two strategies (1, reverse labeling and 2, reverse labeling combining alternate 13C-12C labeling). The signal intensities of some other types of residues in 2D 13C-13C spectra are observed to be 20-50% weaker because of the unwanted reverse labeling. The extensively sparse 13C labeling proposed in this study is expected to be useful in the collection of distance restraints using 2D 13C-13C spectra of membrane proteins.
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Affiliation(s)
- Qiong Tong
- National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, People's Republic of China
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, People's Republic of China
| | - Huan Tan
- National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, People's Republic of China
- University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Jianping Li
- National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, People's Republic of China
| | - Huayong Xie
- National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, People's Republic of China
| | - Yongxiang Zhao
- National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, People's Republic of China
| | - Yanke Chen
- National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, People's Republic of China
| | - Jun Yang
- National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, People's Republic of China.
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, People's Republic of China.
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5
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Redzic JS, Duff MR, Blue A, Pitts TM, Agarwal P, Eisenmesser EZ. Modulating Enzyme Function via Dynamic Allostery within Biliverdin Reductase B. Front Mol Biosci 2021; 8:691208. [PMID: 34095235 PMCID: PMC8173106 DOI: 10.3389/fmolb.2021.691208] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 04/30/2021] [Indexed: 11/17/2022] Open
Abstract
The biliverdin reductase B (BLVRB) class of enzymes catalyze the NADPH-dependent reduction of multiple flavin substrates and are emerging as critical players in cellular redox regulation. However, the role of dynamics and allostery have not been addressed, prompting studies here that have revealed a position 15 Å away from the active site within human BLVRB (T164) that is inherently dynamic and can be mutated to control global micro-millisecond motions and function. By comparing the inherent dynamics through nuclear magnetic resonance (NMR) relaxation approaches of evolutionarily distinct BLVRB homologues and by applying our previously developed Relaxation And Single Site Multiple Mutations (RASSMM) approach that monitors both the functional and dynamic effects of multiple mutations to the single T164 site, we have discovered that the most dramatic mutagenic effects coincide with evolutionary changes and these modulate coenzyme binding. Thus, evolutionarily changing sites distal to the active site serve as dynamic "dials" to globally modulate motions and function. Despite the distal dynamic and functional coupling modulated by this site, micro-millisecond motions span an order of magnitude in their apparent kinetic rates of motions. Thus, global dynamics within BLVRB are a collection of partially coupled motions tied to catalytic function.
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Affiliation(s)
- Jasmina S Redzic
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Colorado Denver, Denver, CO, United States
| | - Michael R Duff
- Biochemistry and Cellular and Molecular Biology Department, University of Tennessee, Knoxville, TN, United States
| | - Ashley Blue
- National High Magnetic Field Laboratory, Tallahassee, FL, United States
| | - Todd M Pitts
- Division of Medical Oncology, School of Medicine, University of Colorado, Aurora, CO, United States
| | - Pratul Agarwal
- Department of Physiological Sciences and High Performance Computing Center, Oklahoma State University, Stillwater, OK, United States
| | - Elan Zohar Eisenmesser
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Colorado Denver, Denver, CO, United States
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6
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Pazicky S, Dhamotharan K, Kaszuba K, Mertens HDT, Gilberger T, Svergun D, Kosinski J, Weininger U, Löw C. Structural role of essential light chains in the apicomplexan glideosome. Commun Biol 2020; 3:568. [PMID: 33051581 PMCID: PMC7555893 DOI: 10.1038/s42003-020-01283-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 09/11/2020] [Indexed: 01/18/2023] Open
Abstract
Gliding, a type of motility based on an actin-myosin motor, is specific to apicomplexan parasites. Myosin A binds two light chains which further interact with glideosome associated proteins and assemble into the glideosome. The role of individual glideosome proteins is unclear due to the lack of structures of larger glideosome assemblies. Here, we investigate the role of essential light chains (ELCs) in Toxoplasma gondii and Plasmodium falciparum and present their crystal structures as part of trimeric sub-complexes. We show that although ELCs bind a conserved MyoA sequence, P. falciparum ELC adopts a distinct structure in the free and MyoA-bound state. We suggest that ELCs enhance MyoA performance by inducing secondary structure in MyoA and thus stiffen its lever arm. Structural and biophysical analysis reveals that calcium binding has no influence on the structure of ELCs. Our work represents a further step towards understanding the mechanism of gliding in Apicomplexa.
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Affiliation(s)
- Samuel Pazicky
- Centre for Structural Systems Biology (CSSB), Notkestrasse 85, D-22607, Hamburg, Germany
- Molecular Biology Laboratory (EMBL), Hamburg Unit c/o Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, D-22607, Hamburg, Germany
| | - Karthikeyan Dhamotharan
- Centre for Structural Systems Biology (CSSB), Notkestrasse 85, D-22607, Hamburg, Germany
- Molecular Biology Laboratory (EMBL), Hamburg Unit c/o Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, D-22607, Hamburg, Germany
| | - Karol Kaszuba
- Centre for Structural Systems Biology (CSSB), Notkestrasse 85, D-22607, Hamburg, Germany
- Molecular Biology Laboratory (EMBL), Hamburg Unit c/o Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, D-22607, Hamburg, Germany
| | - Haydyn D T Mertens
- Molecular Biology Laboratory (EMBL), Hamburg Unit c/o Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, D-22607, Hamburg, Germany
| | - Tim Gilberger
- Centre for Structural Systems Biology (CSSB), Notkestrasse 85, D-22607, Hamburg, Germany
- Bernhard Nocht Institute for Tropical Medicine, Bernhard-Nocht-Strasse 74, D-20359, Hamburg, Germany
- Department of Biology, University of Hamburg, Hamburg, Germany
| | - Dmitri Svergun
- Molecular Biology Laboratory (EMBL), Hamburg Unit c/o Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, D-22607, Hamburg, Germany
| | - Jan Kosinski
- Centre for Structural Systems Biology (CSSB), Notkestrasse 85, D-22607, Hamburg, Germany
- Molecular Biology Laboratory (EMBL), Hamburg Unit c/o Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, D-22607, Hamburg, Germany
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117, Heidelberg, Germany
| | - Ulrich Weininger
- Martin-Luther-University Halle-Wittenberg, Institute of Physics, Biophysics, D-06120, Halle (Saale), Germany
| | - Christian Löw
- Centre for Structural Systems Biology (CSSB), Notkestrasse 85, D-22607, Hamburg, Germany.
- Molecular Biology Laboratory (EMBL), Hamburg Unit c/o Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, D-22607, Hamburg, Germany.
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7
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Lesovoy DM, Dubinnyi MA, Nolde SB, Bocharov EV, Arseniev AS. Accurate measurement of dipole/dipole transverse cross-correlated relaxation [Formula: see text] in methylenes and primary amines of uniformly [Formula: see text]-labeled proteins. JOURNAL OF BIOMOLECULAR NMR 2019; 73:245-260. [PMID: 31089943 DOI: 10.1007/s10858-019-00252-6] [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: 10/31/2018] [Accepted: 05/03/2019] [Indexed: 06/09/2023]
Abstract
Side chains possess a broader conformational space (compared to the backbone) and are directly affected by intra- and intermolecular interactions, hence their dynamics and the corresponding NMR relaxation data are more sensitive and informative. Nevertheless, transverse relaxation in [Formula: see text] ([Formula: see text] or [Formula: see text]) spin systems is predominantly non-measurable in uniformly [Formula: see text]-labeled proteins due to cross-correlation effects. In the present publication, we propose a number of pulse sequences for accurate and precise measurement of the dipole-dipole transverse cross-correlated relaxation rate [Formula: see text], which, similarly to [Formula: see text] measurements, provides information about the amplitudes of intramolecular dynamics. The suggested approach has allowed us to circumvent a number of obstacles that were limiting earlier applications of [Formula: see text]: (1) impossibility of transmission of the central component of the triplet of [Formula: see text] group to [Formula: see text]-acquisition via INEPT has been solved by transmission of the averaged signal of "inner" and "outer" components of the triplet; (2) direct recording of the entire triplets resulting in substantial overlap of side chain signals has been replaced by recording of individual singlets with the use of [Formula: see text]-modulated approach and constant-time evolution; (3) low sensitivity has been enhanced via proton acquisition which required special attention to a zero-quantum coherence evolution. The proposed method expands the set of "dynamics sensors" covering protein side chains and substantially improves the quality and the level of detail of experimental data describing dynamic processes in proteins and protein complexes.
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Affiliation(s)
- Dmitry M Lesovoy
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences RAS, Str. Miklukho-Maklaya 16/10, Moscow, Russian Federation, 117997
| | - Maxim A Dubinnyi
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences RAS, Str. Miklukho-Maklaya 16/10, Moscow, Russian Federation, 117997
- Moscow Institute of Physics and Technology (State University), Institutsky per., 9, Dolgoprudny, Russian Federation, 141700
| | - Svetlana B Nolde
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences RAS, Str. Miklukho-Maklaya 16/10, Moscow, Russian Federation, 117997
| | - Eduard V Bocharov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences RAS, Str. Miklukho-Maklaya 16/10, Moscow, Russian Federation, 117997.
- Moscow Institute of Physics and Technology (State University), Institutsky per., 9, Dolgoprudny, Russian Federation, 141700.
| | - Alexander S Arseniev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences RAS, Str. Miklukho-Maklaya 16/10, Moscow, Russian Federation, 117997
- Moscow Institute of Physics and Technology (State University), Institutsky per., 9, Dolgoprudny, Russian Federation, 141700
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8
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Raum HN, Dreydoppel M, Weininger U. Conformational exchange of aromatic side chains by 1H CPMG relaxation dispersion. JOURNAL OF BIOMOLECULAR NMR 2018; 72:105-114. [PMID: 30229369 PMCID: PMC6209042 DOI: 10.1007/s10858-018-0210-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 09/14/2018] [Indexed: 06/08/2023]
Abstract
Aromatic side chains are attractive probes of protein dynamics on the millisecond time scale, because they are often key residues in enzyme active sites and protein binding sites. Further they allow to study specific processes, like histidine tautomerization and ring flips. Till now such processes have been studied by aromatic 13C CPMG relaxation dispersion experiments. Here we investigate the possibility of aromatic 1H CPMG relaxation dispersion experiments as a complementary method. Artifact-free dispersions are possible on uniformly 1H and 13C labeled samples for histidine δ2 and ε1, as well as for tryptophan δ1. The method has been validated by measuring fast folding-unfolding kinetics of the small protein CspB under native conditions. The determined rate constants and populations agree well with previous results from 13C CPMG relaxation dispersion experiments. The CPMG-derived chemical shift differences between the folded and unfolded states are in good agreement with those obtained directly from the spectra. In contrast, the 1H relaxation dispersion profiles in phenylalanine, tyrosine and the six-ring moiety of tryptophan, display anomalous behavior caused by 3J 1H-1H couplings and, if present, strong 13C-13C couplings. Therefore they require site-selective 1H/2H and, in case of strong couplings, 13C/12C labeling. In summary, aromatic 1H CPMG relaxation dispersion experiments work on certain positions (His δ2, His ε1 and Trp δ1) in uniformly labeled samples, while other positions require site-selective isotope labeling.
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Affiliation(s)
- Heiner N Raum
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Matthias Dreydoppel
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Ulrich Weininger
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, 06120, Halle (Saale), Germany.
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9
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Weininger U. Optimal Isotope Labeling of Aromatic Amino Acid Side Chains for NMR Studies of Protein Dynamics. Methods Enzymol 2018; 614:67-86. [PMID: 30611433 DOI: 10.1016/bs.mie.2018.08.028] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Aromatic side chains in proteins are often directly evolved in stabilizing the hydrophobic core, protein binding, or enzymatic activity. They are also responsible for specific local dynamic processes, such as histidine tautomerization or ring flips. Despite their importance, they are often not targeted directly by NMR spectroscopy, because of spectroscopic complications and challenges. This chapter addresses state-of-the-art site-selective 13C-labeling methods for aromatic side chains, and describes how they solve several of the spectroscopic issues. A special emphasis is put on thereby enabled protein dynamics experiments of aromatic side chains.
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Affiliation(s)
- Ulrich Weininger
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, Halle, Germany.
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10
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Analysis of Artifacts Caused by Pulse Imperfections in CPMG Pulse Trains in NMR Relaxation Dispersion Experiments. MAGNETOCHEMISTRY 2018. [DOI: 10.3390/magnetochemistry4030033] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Nuclear magnetic resonance relaxation dispersion (rd) experiments provide kinetics and thermodynamics information of molecules undergoing conformational exchange. Rd experiments often use a Carr-Purcell-Meiboom-Gill (CPMG) pulse train equally separated by a spin-state selective inversion element (U-element). Even with measurement parameters carefully set, however, parts of 1H–15N correlations sometimes exhibit large artifacts that may hamper the subsequent analyses. We analyzed such artifacts with a combination of NMR measurements and simulation. We found that particularly the lowest CPMG frequency (νcpmg) can also introduce large artifacts into amide 1H–15N and aromatic 1H–13C correlations whose 15N/13C resonances are very close to the carrier frequencies. The simulation showed that the off-resonance effects and miscalibration of the CPMG π pulses generate artifact maxima at resonance offsets of even and odd multiples of νcpmg, respectively. We demonstrate that a method once introduced into the rd experiments for molecules having residual dipolar coupling significantly reduces artifacts. In the method the 15N/13C π pulse phase in the U-element is chosen between x and y. We show that the correctly adjusted sequence is tolerant to miscalibration of the CPMG π pulse power as large as ±10% for most amide 15N and aromatic 13C resonances of proteins.
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11
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Schörghuber J, Geist L, Platzer G, Feichtinger M, Bisaccia M, Scheibelberger L, Weber F, Konrat R, Lichtenecker RJ. Late metabolic precursors for selective aromatic residue labeling. JOURNAL OF BIOMOLECULAR NMR 2018; 71:129-140. [PMID: 29808436 PMCID: PMC6096522 DOI: 10.1007/s10858-018-0188-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 05/19/2018] [Indexed: 06/08/2023]
Abstract
In recent years, we developed a toolbox of heavy isotope containing compounds, which serve as metabolic amino acid precursors in the E. coli-based overexpression of aromatic residue labeled proteins. Our labeling techniques show excellent results both in terms of selectivity and isotope incorporation levels. They are additionally distinguished by low sample production costs and meet the economic demands to further implement protein NMR spectroscopy as a routinely used method in drug development processes. Different isotopologues allow for the assembly of optimized protein samples, which fulfill the requirements of various NMR experiments to elucidate protein structures, analyze conformational dynamics, or probe interaction surfaces. In the present article, we want to summarize the precursors we developed so far and give examples of their special value in the probing of protein-ligand interaction.
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Affiliation(s)
- Julia Schörghuber
- Institute of Organic Chemistry, University of Vienna, Währinger Str. 38, 1090, Vienna, Austria
| | - Leonhard Geist
- Christian Doppler Laboratory for High-Content Structural Biology and Biotechnology, Department of Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Dr-Bohr-Gasse 9, 1030, Vienna, Austria
| | - Gerald Platzer
- Christian Doppler Laboratory for High-Content Structural Biology and Biotechnology, Department of Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Dr-Bohr-Gasse 9, 1030, Vienna, Austria
| | - Michael Feichtinger
- Christian Doppler Laboratory for High-Content Structural Biology and Biotechnology, Department of Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Dr-Bohr-Gasse 9, 1030, Vienna, Austria
| | - Marilena Bisaccia
- Institute of Organic Chemistry, University of Vienna, Währinger Str. 38, 1090, Vienna, Austria
| | - Lukas Scheibelberger
- Institute of Organic Chemistry, University of Vienna, Währinger Str. 38, 1090, Vienna, Austria
| | - Frederik Weber
- Institute of Organic Chemistry, University of Vienna, Währinger Str. 38, 1090, Vienna, Austria
| | - Robert Konrat
- Christian Doppler Laboratory for High-Content Structural Biology and Biotechnology, Department of Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Dr-Bohr-Gasse 9, 1030, Vienna, Austria
| | - Roman J Lichtenecker
- Institute of Organic Chemistry, University of Vienna, Währinger Str. 38, 1090, Vienna, Austria.
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12
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Schörghuber J, Geist L, Bisaccia M, Weber F, Konrat R, Lichtenecker RJ. Anthranilic acid, the new player in the ensemble of aromatic residue labeling precursor compounds. JOURNAL OF BIOMOLECULAR NMR 2017; 69:13-22. [PMID: 28861670 PMCID: PMC5626795 DOI: 10.1007/s10858-017-0129-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 08/28/2017] [Indexed: 06/07/2023]
Abstract
The application of metabolic precursors for selective stable isotope labeling of aromatic residues in cell-based protein overexpression has already resulted in numerous NMR probes to study the structural and dynamic characteristics of proteins. With anthranilic acid, we present the structurally simplest precursor for exclusive tryptophan side chain labeling. A synthetic route to 13C, 2H isotopologues allows the installation of isolated 13C-1H spin systems in the indole ring of tryptophan, representing a versatile tool to investigate side chain motion using relaxation-based experiments without the loss of magnetization due to strong 1JCC and weaker 2JCH scalar couplings, as well as dipolar interactions with remote hydrogens. In this article, we want to introduce this novel precursor in the context of hitherto existing techniques of in vivo aromatic residue labeling.
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Affiliation(s)
- Julia Schörghuber
- Institute of Organic Chemistry, University of Vienna, Währingerstr. 38, 1090, Vienna, Austria
| | - Leonhard Geist
- Christian Doppler Laboratory for High-Content Structural Biology and Biotechnology, Department of Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Dr-Bohr-Gasse 9, 1030, Vienna, Austria
| | - Marilena Bisaccia
- Institute of Organic Chemistry, University of Vienna, Währingerstr. 38, 1090, Vienna, Austria
| | - Frederik Weber
- Institute of Organic Chemistry, University of Vienna, Währingerstr. 38, 1090, Vienna, Austria
| | - Robert Konrat
- Christian Doppler Laboratory for High-Content Structural Biology and Biotechnology, Department of Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Dr-Bohr-Gasse 9, 1030, Vienna, Austria
| | - Roman J Lichtenecker
- Institute of Organic Chemistry, University of Vienna, Währingerstr. 38, 1090, Vienna, Austria.
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13
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Weininger U. Site-selective 13C labeling of histidine and tryptophan using ribose. JOURNAL OF BIOMOLECULAR NMR 2017; 69:23-30. [PMID: 28856561 PMCID: PMC5626788 DOI: 10.1007/s10858-017-0130-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 08/28/2017] [Indexed: 06/07/2023]
Abstract
Experimental studies on protein dynamics at atomic resolution by NMR-spectroscopy in solution require isolated 1H-X spin pairs. This is the default scenario in standard 1H-15N backbone experiments. Side chain dynamic experiments, which allow to study specific local processes like proton-transfer, or tautomerization, require isolated 1H-13C sites which must be produced by site-selective 13C labeling. In the most general way this is achieved by using site-selectively 13C-enriched glucose as the carbon source in bacterial expression systems. Here we systematically investigate the use of site-selectively 13C-enriched ribose as a suitable precursor for 13C labeled histidines and tryptophans. The 13C incorporation in nearly all sites of all 20 amino acids was quantified and compared to glucose based labeling. In general the ribose approach results in more selective labeling. 1-13C ribose exclusively labels His δ2 and Trp δ1 in aromatic side chains and helps to resolve possible overlap problems. The incorporation yield is however only 37% in total and 72% compared to yields of 2-13C glucose. A combined approach of 1-13C ribose and 2-13C glucose maximizes 13C incorporation to 75% in total and 150% compared to 2-13C glucose only. Further histidine positions β, α and CO become significantly labeled at around 50% in total by 3-, 4- or 5-13C ribose. Interestingly backbone CO of Gly, Ala, Cys, Ser, Val, Phe and Tyr are labeled at 40-50% in total with 3-13C ribose, compared to 5% and below for 1-13C and 2-13C glucose. Using ribose instead of glucose as a source for site-selective 13C labeling enables a very selective labeling of certain positions and thereby expanding the toolbox for customized isotope labeling of amino-acids.
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Affiliation(s)
- Ulrich Weininger
- Department of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, P. O. Box 124, 22100, Lund, Sweden.
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, 06120, Halle (Saale), Germany.
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14
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Weininger U. Site-selective 13C labeling of proteins using erythrose. JOURNAL OF BIOMOLECULAR NMR 2017; 67:191-200. [PMID: 28247186 PMCID: PMC5388708 DOI: 10.1007/s10858-017-0096-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2016] [Accepted: 02/10/2017] [Indexed: 06/06/2023]
Abstract
NMR-spectroscopy enables unique experimental studies on protein dynamics at atomic resolution. In order to obtain a full atom view on protein dynamics, and to study specific local processes like ring-flips, proton-transfer, or tautomerization, one has to perform studies on amino-acid side chains. A key requirement for these studies is site-selective labeling with 13C and/or 1H, which is achieved in the most general way by using site-selectively 13C-enriched glucose (1- and 2-13C) as the carbon source in bacterial expression systems. Using this strategy, multiple sites in side chains, including aromatics, become site-selectively labeled and suitable for relaxation studies. Here we systematically investigate the use of site-selectively 13C-enriched erythrose (1-, 2-, 3- and 4-13C) as a suitable precursor for 13C labeled aromatic side chains. We quantify 13C incorporation in nearly all sites in all 20 amino acids and compare the results to glucose based labeling. In general the erythrose approach results in more selective labeling. While there is only a minor gain for phenylalanine and tyrosine side-chains, the 13C incorporation level for tryptophan is at least doubled. Additionally, the Phe ζ and Trp η2 positions become labeled. In the aliphatic side chains, labeling using erythrose yields isolated 13C labels for certain positions, like Ile β and His β, making these sites suitable for dynamics studies. Using erythrose instead of glucose as a source for site-selective 13C labeling enables unique or superior labeling for certain positions and is thereby expanding the toolbox for customized isotope labeling of amino-acid side-chains.
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Affiliation(s)
- Ulrich Weininger
- Department of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, P.O. Box 124, 22100, Lund, Sweden.
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, 06120, Halle (Saale), Germany.
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15
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Weininger U, Modig K, Geitner AJ, Schmidpeter PAM, Koch JR, Akke M. Dynamics of Aromatic Side Chains in the Active Site of FKBP12. Biochemistry 2016; 56:334-343. [DOI: 10.1021/acs.biochem.6b01157] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Ulrich Weininger
- Department
of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, P.O.
Box 124, SE-22100 Lund, Sweden
- Institute
of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, D-06120 Halle (Saale), Germany
| | - Kristofer Modig
- Department
of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, P.O.
Box 124, SE-22100 Lund, Sweden
| | - Anne-Juliane Geitner
- Laboratorium
für Biochemie, Bayreuther Zentrum für Molekulare Biowissenschaften, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - Philipp A. M. Schmidpeter
- Laboratorium
für Biochemie, Bayreuther Zentrum für Molekulare Biowissenschaften, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - Johanna R. Koch
- Laboratorium
für Biochemie, Bayreuther Zentrum für Molekulare Biowissenschaften, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - Mikael Akke
- Department
of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, P.O.
Box 124, SE-22100 Lund, Sweden
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16
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Longhini AP, LeBlanc RM, Becette O, Salguero C, Wunderlich CH, Johnson BA, D'Souza VM, Kreutz C, Dayie TK. Chemo-enzymatic synthesis of site-specific isotopically labeled nucleotides for use in NMR resonance assignment, dynamics and structural characterizations. Nucleic Acids Res 2015; 44:e52. [PMID: 26657632 PMCID: PMC4824079 DOI: 10.1093/nar/gkv1333] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 11/16/2015] [Indexed: 11/12/2022] Open
Abstract
Stable isotope labeling is central to NMR studies of nucleic acids. Development of methods that incorporate labels at specific atomic positions within each nucleotide promises to expand the size range of RNAs that can be studied by NMR. Using recombinantly expressed enzymes and chemically synthesized ribose and nucleobase, we have developed an inexpensive, rapid chemo-enzymatic method to label ATP and GTP site specifically and in high yields of up to 90%. We incorporated these nucleotides into RNAs with sizes ranging from 27 to 59 nucleotides using in vitro transcription: A-Site (27 nt), the iron responsive elements (29 nt), a fluoride riboswitch from Bacillus anthracis (48 nt), and a frame-shifting element from a human corona virus (59 nt). Finally, we showcase the improvement in spectral quality arising from reduced crowding and narrowed linewidths, and accurate analysis of NMR relaxation dispersion (CPMG) and TROSY-based CEST experiments to measure μs-ms time scale motions, and an improved NOESY strategy for resonance assignment. Applications of this selective labeling technology promises to reduce difficulties associated with chemical shift overlap and rapid signal decay that have made it challenging to study the structure and dynamics of large RNAs beyond the 50 nt median size found in the PDB.
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Affiliation(s)
- Andrew P Longhini
- Center for Biomolecular Structure and Organization, Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USAfi
| | - Regan M LeBlanc
- Center for Biomolecular Structure and Organization, Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USAfi
| | - Owen Becette
- Center for Biomolecular Structure and Organization, Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USAfi
| | - Carolina Salguero
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
| | - Christoph H Wunderlich
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, 6020 Innsbruck, Austria
| | - Bruce A Johnson
- Structural Biology Initiative, CUNY Advanced Science Research Center, 85 St. Nicholas Terrace, New York, NY 10031, USA One Moon Scientific, Inc., 839 Grant Avenue, Westfield, NJ 07090-2322, USA
| | - Victoria M D'Souza
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
| | - Christoph Kreutz
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, 6020 Innsbruck, Austria
| | - T Kwaku Dayie
- Center for Biomolecular Structure and Organization, Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USAfi
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17
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Yang CJ, Takeda M, Terauchi T, Jee J, Kainosho M. Differential Large-Amplitude Breathing Motions in the Interface of FKBP12–Drug Complexes. Biochemistry 2015; 54:6983-95. [DOI: 10.1021/acs.biochem.5b00820] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Chun-Jiun Yang
- Department
of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, 1-1 minami-ohsawa, Hachioji,
Tokyo 192-0397, Japan
| | - Mitsuhiro Takeda
- Structural
Biology Research Center, Graduate School of Science, Nagoya University, Furo-cho,
Chikusa-ku, Nagoya 464-8602, Japan
| | - Tsutomu Terauchi
- Department
of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, 1-1 minami-ohsawa, Hachioji,
Tokyo 192-0397, Japan
| | - JunGoo Jee
- Department
of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, 1-1 minami-ohsawa, Hachioji,
Tokyo 192-0397, Japan
| | - Masatsune Kainosho
- Department
of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, 1-1 minami-ohsawa, Hachioji,
Tokyo 192-0397, Japan
- Structural
Biology Research Center, Graduate School of Science, Nagoya University, Furo-cho,
Chikusa-ku, Nagoya 464-8602, Japan
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18
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Schörghuber J, Sára T, Bisaccia M, Schmid W, Konrat R, Lichtenecker RJ. Novel approaches in selective tryptophan isotope labeling by using Escherichia coli overexpression media. Chembiochem 2015; 16:746-51. [PMID: 25703586 DOI: 10.1002/cbic.201402677] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Indexed: 01/25/2023]
Abstract
NMR-based investigations of large protein complexes require optimized isotopic labeling schemes. We report new methods to introduce stable isotopes into tryptophan residues; these are fine-tuned to the requirements of the particular protein NMR experiment. Selective backbone labeling was performed by using a new α-ketoacid precursor as an additive in cell-based overexpression media. Additionally, we developed synthetic routes to certain isotopologues of indole with (13)C-(1)H spin systems surrounded by (12)C and (2)H. The corresponding proteins, overexpressed in the presence of these precursor compounds, can be effectively analyzed for conformational changes in tryptophan residues in response to external stimuli, such as interaction with other proteins or small molecules.
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Affiliation(s)
- Julia Schörghuber
- Institute of Organic Chemistry, University of Vienna, Währingerstrasse 38, 1090 Vienna (Austria)
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19
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Weininger U, Brath U, Modig K, Teilum K, Akke M. Off-resonance rotating-frame relaxation dispersion experiment for 13C in aromatic side chains using L-optimized TROSY-selection. JOURNAL OF BIOMOLECULAR NMR 2014; 59:23-9. [PMID: 24706175 PMCID: PMC4003406 DOI: 10.1007/s10858-014-9826-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 03/25/2014] [Indexed: 05/04/2023]
Abstract
Protein dynamics on the microsecond-millisecond time scales often play a critical role in biological function. NMR relaxation dispersion experiments are powerful approaches for investigating biologically relevant dynamics with site-specific resolution, as shown by a growing number of publications on enzyme catalysis, protein folding, ligand binding, and allostery. To date, the majority of studies has probed the backbone amides or side-chain methyl groups, while experiments targeting other sites have been used more sparingly. Aromatic side chains are useful probes of protein dynamics, because they are over-represented in protein binding interfaces, have important catalytic roles in enzymes, and form a sizable part of the protein interior. Here we present an off-resonance R 1ρ experiment for measuring microsecond to millisecond conformational exchange of aromatic side chains in selectively (13)C labeled proteins by means of longitudinal- and transverse-relaxation optimization. Using selective excitation and inversion of the narrow component of the (13)C doublet, the experiment achieves significant sensitivity enhancement in terms of both signal intensity and the fractional contribution from exchange to transverse relaxation; additional signal enhancement is achieved by optimizing the longitudinal relaxation recovery of the covalently attached (1)H spins. We validated the L-TROSY-selected R 1ρ experiment by measuring exchange parameters for Y23 in bovine pancreatic trypsin inhibitor at a temperature of 328 K, where the ring flip is in the fast exchange regime with a mean waiting time between flips of 320 μs. The determined chemical shift difference matches perfectly with that measured from the NMR spectrum at lower temperatures, where separate peaks are observed for the two sites. We further show that potentially complicating effects of strong scalar coupling between protons (Weininger et al. in J Phys Chem B 117: 9241-9247, 2013b) can be accounted for using a simple expression, and provide recommendations for data acquisition when the studied system exhibits this behavior. The present method extends the repertoire of relaxation methods tailored for aromatic side chains by enabling studies of faster processes and improved control over artifacts due to strong coupling.
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Affiliation(s)
- Ulrich Weininger
- Department of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, P.O. Box 124, 22100 Lund, Sweden
| | - Ulrika Brath
- Department of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, P.O. Box 124, 22100 Lund, Sweden
- Present Address: Department of Chemistry and Molecular Biology, University of Gothenburg, 41296 Göteborg, Sweden
| | - Kristofer Modig
- Department of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, P.O. Box 124, 22100 Lund, Sweden
| | - Kaare Teilum
- Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, 2200 Copenhagen, Denmark
| | - Mikael Akke
- Department of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, P.O. Box 124, 22100 Lund, Sweden
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20
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Xu G, Ye Y, Liu X, Cao S, Wu Q, Cheng K, Liu M, Pielak GJ, Li C. Strategies for Protein NMR in Escherichia coli. Biochemistry 2014; 53:1971-81. [DOI: 10.1021/bi500079u] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Guohua Xu
- Key
Laboratory of Magnetic Resonance in Biological Systems, State Key
Laboratory of Magnetic Resonance and Atomic and Molecular Physics,
Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China
| | - Yansheng Ye
- Key
Laboratory of Magnetic Resonance in Biological Systems, State Key
Laboratory of Magnetic Resonance and Atomic and Molecular Physics,
Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China
- Graduate University of Chinese Academy of Sciences, Beijing 100029, P. R. China
| | - Xiaoli Liu
- Key
Laboratory of Magnetic Resonance in Biological Systems, State Key
Laboratory of Magnetic Resonance and Atomic and Molecular Physics,
Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China
| | - Shufen Cao
- Key
Laboratory of Magnetic Resonance in Biological Systems, State Key
Laboratory of Magnetic Resonance and Atomic and Molecular Physics,
Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China
| | - Qiong Wu
- Key
Laboratory of Magnetic Resonance in Biological Systems, State Key
Laboratory of Magnetic Resonance and Atomic and Molecular Physics,
Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China
| | - Kai Cheng
- Key
Laboratory of Magnetic Resonance in Biological Systems, State Key
Laboratory of Magnetic Resonance and Atomic and Molecular Physics,
Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China
- Graduate University of Chinese Academy of Sciences, Beijing 100029, P. R. China
| | - Maili Liu
- Key
Laboratory of Magnetic Resonance in Biological Systems, State Key
Laboratory of Magnetic Resonance and Atomic and Molecular Physics,
Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China
| | - Gary J. Pielak
- Department
of Chemistry and Department of Biochemistry and Biophysics, University of North Carolina−Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Conggang Li
- Key
Laboratory of Magnetic Resonance in Biological Systems, State Key
Laboratory of Magnetic Resonance and Atomic and Molecular Physics,
Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China
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21
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Lichtenecker RJ. Synthesis of aromatic 13C/2H-α-ketoacid precursors to be used in selective phenylalanine and tyrosine protein labelling. Org Biomol Chem 2014; 12:7551-60. [DOI: 10.1039/c4ob01129e] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A synthetic concept to access various 13C/2H patterns of phenylalanine and tyrosine precursors for cell-based protein overexpression systems is presented. The target compounds feature isolated 13C–1H spin systems to be used in NMR probing of protein structure and dynamics.
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Affiliation(s)
- R. J. Lichtenecker
- Institute of Organic Chemistry
- University of Vienna
- A-1090 Vienna, Austria
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22
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Weininger U, Respondek M, Löw C, Akke M. Slow Aromatic Ring Flips Detected Despite Near-Degenerate NMR Frequencies of the Exchanging Nuclei. J Phys Chem B 2013; 117:9241-7. [DOI: 10.1021/jp4058065] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ulrich Weininger
- Department of Biophysical Chemistry,
Center for Molecular Protein Science, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
| | - Michal Respondek
- Department of Biophysical Chemistry,
Center for Molecular Protein Science, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
| | - Christian Löw
- Department of Medical Biochemistry
and Biophysics, Karolinska Institute, SE-171
77 Stockholm, Sweden
| | - Mikael Akke
- Department of Biophysical Chemistry,
Center for Molecular Protein Science, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
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23
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Sathyamoorthy B, Singarapu KK, Garcia AE, Szyperski T. Protein conformational space populated in solution probed with aromatic residual dipolar (13) C-(1) H couplings. Chembiochem 2013; 14:684-8. [PMID: 23494854 DOI: 10.1002/cbic.201300016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Indexed: 02/02/2023]
Abstract
The use of aromatic (13) C-(1) H residual dipolar couplings (RDCs) to probe the conformational space populated in solution is demonstrated for the protein BPTI. RDCs allow one to assess accuracy of atomic resolution structures and potentially to characterize low-populated subspaces corresponding to "excited states" in conformationally labile systems. They also allow one to assess sampling accuracy of molecular dynamics simulations.
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Affiliation(s)
- Bharathwaj Sathyamoorthy
- Department of Chemistry, State University of New York at Buffalo, North Campus, Buffalo, NY 14260, USA
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24
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Weininger U, Respondek M, Akke M. Conformational exchange of aromatic side chains characterized by L-optimized TROSY-selected ¹³C CPMG relaxation dispersion. JOURNAL OF BIOMOLECULAR NMR 2012; 54:9-14. [PMID: 22833056 PMCID: PMC3427480 DOI: 10.1007/s10858-012-9656-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Accepted: 07/12/2012] [Indexed: 05/12/2023]
Abstract
Protein dynamics on the millisecond time scale commonly reflect conformational transitions between distinct functional states. NMR relaxation dispersion experiments have provided important insights into biologically relevant dynamics with site-specific resolution, primarily targeting the protein backbone and methyl-bearing side chains. Aromatic side chains represent attractive probes of protein dynamics because they are over-represented in protein binding interfaces, play critical roles in enzyme catalysis, and form an important part of the core. Here we introduce a method to characterize millisecond conformational exchange of aromatic side chains in selectively (13)C labeled proteins by means of longitudinal- and transverse-relaxation optimized CPMG relaxation dispersion. By monitoring (13)C relaxation in a spin-state selective manner, significant sensitivity enhancement can be achieved in terms of both signal intensity and the relative exchange contribution to transverse relaxation. Further signal enhancement results from optimizing the longitudinal relaxation recovery of the covalently attached (1)H spins. We validated the L-TROSY-CPMG experiment by measuring fast folding-unfolding kinetics of the small protein CspB under native conditions. The determined unfolding rate matches perfectly with previous results from stopped-flow kinetics. The CPMG-derived chemical shift differences between the folded and unfolded states are in excellent agreement with those obtained by urea-dependent chemical shift analysis. The present method enables characterization of conformational exchange involving aromatic side chains and should serve as a valuable complement to methods developed for other types of protein side chains.
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Affiliation(s)
- Ulrich Weininger
- Department of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, P.O. Box 124, 22100 Lund, Sweden
| | - Michal Respondek
- Department of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, P.O. Box 124, 22100 Lund, Sweden
| | - Mikael Akke
- Department of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, P.O. Box 124, 22100 Lund, Sweden
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