1
|
Joshi K, Bhuyan AK. Glycerol-slaved 1H- 1H NMR cross-relaxation in quasi-native lysozyme. Biophys Chem 2024; 312:107286. [PMID: 38964115 DOI: 10.1016/j.bpc.2024.107286] [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: 05/11/2024] [Revised: 06/14/2024] [Accepted: 06/26/2024] [Indexed: 07/06/2024]
Abstract
1H-1H nuclear cross-relaxation experiments have been carried out with lysozyme in variable glycerol viscosity to study intramolecular motion, self-diffusion, and isotropic rigid-body rotational tumbling at 298 K, pH 3.8. Dynamics of intramolecular 1H-1H cross-relaxation rates, the increase in internuclear spatial distances, and lateral and rotational diffusion coefficients all show fractional viscosity dependence with a power law exponent κ in the 0.17-0.83 range. The diffusion coefficient of glycerol Ds with the bulk viscosity itself is non-Stokesian, having a fractional viscosity dependence on the medium viscosity (Ds ∼ η-κ, κ ≈ 0.71). The concurrence and close similarity of the fractional viscosity dependence of glycerol diffusion on the one hand, and diffusion and intramolecular cross-relaxation rates of the protein on the other lead to infer that relaxation of glycerol slaves protein relaxations. Glycerol-transformed native lysozyme to a quasi-native state does not affect the conclusion that both global and internal fluctuations are slaved to glycerol relaxation.
Collapse
Affiliation(s)
- Kirthi Joshi
- School of Chemistry, University of Hyderabad, Hyderabad 50046, India
| | - Abani K Bhuyan
- School of Chemistry, University of Hyderabad, Hyderabad 50046, India.
| |
Collapse
|
2
|
Banayan NE, Hsu A, Hunt JF, Palmer AG, Friesner RA. Parsing Dynamics of Protein Backbone NH and Side-Chain Methyl Groups using Molecular Dynamics Simulations. J Chem Theory Comput 2024; 20:6316-6327. [PMID: 38957960 DOI: 10.1021/acs.jctc.4c00378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/04/2024]
Abstract
Experimental NMR spectroscopy and theoretical molecular dynamics (MD) simulations provide complementary insights into protein conformational dynamics and hence into biological function. The present work describes an extensive set of backbone NH and side-chain methyl group generalized order parameters for the Escherichia coli ribonuclease HI (RNH) enzyme derived from 2-μs microsecond MD simulations using the OPLS4 and AMBER-FF19SB force fields. The simulated generalized order parameters are compared with values derived from NMR 15N and 13CH2D spin relaxation measurements. The squares of the generalized order parameters, S2 for the N-H bond vector and Saxis2 for the methyl group symmetry axis, characterize the equilibrium distribution of vector orientations in a molecular frame of reference. Optimal agreement between simulated and experimental results was obtained by averaging S2 or Saxis2 calculated by dividing the simulated trajectories into 50 ns blocks (∼five times the rotational diffusion correlation time for RNH). With this procedure, the median absolute deviations (MAD) between experimental and simulated values of S2 and Saxis2 are 0.030 (NH) and 0.061 (CH3) for OPLS4 and 0.041 (NH) and 0.078 (CH3) for AMBER-FF19SB. The MAD between OPLS4 and AMBER-FF19SB are 0.021 (NH) and 0.072 (CH3). The generalized order parameters for the methyl group symmetry axis can be decomposed into contributions from backbone fluctuations, between-rotamer dihedral angle transitions, and within-rotamer dihedral angle fluctuations. Analysis of the simulation trajectories shows that (i) backbone and side chain conformational fluctuations exhibit little correlation and that (ii) fluctuations within rotamers are limited and highly uniform with values that depend on the number of dihedral angles considered. Low values of Saxis2, indicative of enhanced side-chain flexibility, result from between-rotamer transitions that can be enhanced by increased local backbone flexibility.
Collapse
Affiliation(s)
- Nooriel E Banayan
- Department of Biological Sciences, Columbia University, 3000 Broadway, New York, New York 10027, United States
| | - Andrew Hsu
- Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, United States
| | - John F Hunt
- Department of Biological Sciences, Columbia University, 3000 Broadway, New York, New York 10027, United States
| | - Arthur G Palmer
- Department of Biochemistry and Molecular Biophysics, Columbia University, 701 West 168th Street, New York, New York 10032, United States
| | - Richard A Friesner
- Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, United States
| |
Collapse
|
3
|
Dudley JA, Park S, Cho O, Wells NGM, MacDonald ME, Blejec KM, Fetene E, Zanderigo E, Houliston S, Liddle JC, Dashnaw CM, Sabo TM, Shaw BF, Balsbaugh JL, Rocklin GJ, Smith CA. Heat-induced structural and chemical changes to a computationally designed miniprotein. Protein Sci 2024; 33:e4991. [PMID: 38757381 PMCID: PMC11099715 DOI: 10.1002/pro.4991] [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: 12/11/2023] [Revised: 03/22/2024] [Accepted: 03/28/2024] [Indexed: 05/18/2024]
Abstract
The de novo design of miniprotein inhibitors has recently emerged as a new technology to create proteins that bind with high affinity to specific therapeutic targets. Their size, ease of expression, and apparent high stability makes them excellent candidates for a new class of protein drugs. However, beyond circular dichroism melts and hydrogen/deuterium exchange experiments, little is known about their dynamics, especially at the elevated temperatures they seemingly tolerate quite well. To address that and gain insight for future designs, we have focused on identifying unintended and previously overlooked heat-induced structural and chemical changes in a particularly stable model miniprotein, EHEE_rd2_0005. Nuclear magnetic resonance (NMR) studies suggest the presence of dynamics on multiple time and temperature scales. Transiently elevating the temperature results in spontaneous chemical deamidation visible in the NMR spectra, which we validate using both capillary electrophoresis and mass spectrometry (MS) experiments. High temperatures also result in greatly accelerated intrinsic rates of hydrogen exchange and signal loss in NMR heteronuclear single quantum coherence spectra from local unfolding. These losses are in excellent agreement with both room temperature hydrogen exchange experiments and hydrogen bond disruption in replica exchange molecular dynamics simulations. Our analysis reveals important principles for future miniprotein designs and the potential for high stability to result in long-lived alternate conformational states.
Collapse
Affiliation(s)
- Joshua A. Dudley
- Department of ChemistryWesleyan UniversityMiddletownConnecticutUSA
| | - Sojeong Park
- Department of ChemistryWesleyan UniversityMiddletownConnecticutUSA
| | - Oliver Cho
- Department of ChemistryWesleyan UniversityMiddletownConnecticutUSA
| | | | | | | | - Emmanuel Fetene
- Department of ChemistryWesleyan UniversityMiddletownConnecticutUSA
| | - Eric Zanderigo
- Department of ChemistryWesleyan UniversityMiddletownConnecticutUSA
| | - Scott Houliston
- Structural Genomics ConsortiumUniversity of TorontoTorontoOntarioCanada
| | - Jennifer C. Liddle
- Proteomics and Metabolomics FacilityUniversity of ConnecticutStorrsConnecticutUSA
| | - Chad M. Dashnaw
- Department of Chemistry and BiochemistryBaylor UniversityWacoTexasUSA
| | - T. Michael Sabo
- Department of Medicine and Brown Cancer CenterUniversity of LouisvilleLouisvilleKentuckyUSA
| | - Bryan F. Shaw
- Department of Chemistry and BiochemistryBaylor UniversityWacoTexasUSA
| | - Jeremy L. Balsbaugh
- Proteomics and Metabolomics FacilityUniversity of ConnecticutStorrsConnecticutUSA
| | - Gabriel J. Rocklin
- Department of Pharmacology and Center for Synthetic BiologyNorthwestern UniversityEvanstonIllinoisUSA
| | - Colin A. Smith
- Department of ChemistryWesleyan UniversityMiddletownConnecticutUSA
| |
Collapse
|
4
|
Thakur N, Ray AP, Lyman E, Gao ZG, Jacobson KA, Eddy MT. Membrane Mimetic-Dependence of GPCR Energy Landscapes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.16.562552. [PMID: 37905159 PMCID: PMC10614885 DOI: 10.1101/2023.10.16.562552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
Protein function strongly depends on temperature, which is related to temperature-dependent changes in the equilibria of protein conformational states. We leveraged variable-temperature 19F-NMR spectroscopy to interrogate the temperature dependence of the conformational landscape of the human A2A adenosine receptor (A2AAR), a class A GPCR. Temperature-induced changes in the conformational equilibria of A2AAR in lipid nanodiscs were markedly dependent on the efficacy of bound drugs. While antagonist complexes displayed only modest changes as the temperature rose, both full and partial agonist complexes exhibited substantial increases in the active state population. Importantly, the temperature-dependent response of complexes with both full and partial agonists exhibited a pronounced sensitivity to the specific membrane mimetic employed. In striking contrast to observations within lipid nanodiscs, in detergent micelles the active state population exhibited different behavior for A2AAR complexes with both full and partial agonists. This underscores the importance of the protein environment in understanding the thermodynamics of GPCR activation.
Collapse
Affiliation(s)
- Naveen Thakur
- Department of Chemistry, University of Florida, 126 Sisler Hall, Gainesville, FL 32611, USA
| | - Arka Prabha Ray
- Department of Chemistry, University of Florida, 126 Sisler Hall, Gainesville, FL 32611, USA
| | - Edward Lyman
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware, USA
| | - Zhan-Guo Gao
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kenneth A Jacobson
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Matthew T Eddy
- Department of Chemistry, University of Florida, 126 Sisler Hall, Gainesville, FL 32611, USA
| |
Collapse
|
5
|
Kulkarni M, Söderhjelm P. Free-Energy Landscape and Rate Estimation of the Aromatic Ring Flips in Basic Pancreatic Trypsin Inhibitors Using Metadynamics. J Chem Theory Comput 2023; 19:6605-6618. [PMID: 37698852 PMCID: PMC10569046 DOI: 10.1021/acs.jctc.3c00460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Indexed: 09/13/2023]
Abstract
Aromatic side chains (phenylalanine and tyrosine) of a protein flip by 180° around the Cβ-Cγ axis (χ2 dihedral of the side chain), producing two symmetry-equivalent states. The study of ring flip dynamics with nuclear magnetic resonance (NMR) experiments helps to understand local conformational fluctuations. Ring flips are categorized as slow (milliseconds and onward) or fast (nanoseconds to near milliseconds) based on timescales accessible to NMR experiments. In this study, we investigated the ability of the infrequent metadynamics approach to estimate the flip rate and discriminate between slow and fast ring flips for eight individual aromatic side chains (F4, Y10, Y21, F22, Y23, F33, Y35, and F45) of the basic pancreatic trypsin inhibitor. Well-tempered metadynamics simulations were performed to estimate the ring-flipping free-energy surfaces for all eight aromatic residues. The results indicate that χ2 as a standalone collective variable (CV) is not sufficient to obtain computationally consistent results. Inclusion of a complementary CV, such as χ1(Cα-Cβ), solved the problem for most residues and enabled us to classify fast and slow ring flips. This indicates the importance of librational motions in ring flips. Multiple pathways and mechanisms were observed for residues F4, Y10, and F22. Recrossing events were observed for residues F22 and F33, indicating a possible role of friction effects in ring flipping. The results demonstrate the successful application of infrequent metadynamics to estimate ring flip rates and identify certain limitations of the approach.
Collapse
Affiliation(s)
- Mandar Kulkarni
- Division of Biophysical Chemistry, Lund University, Chemical Center, 22100 Lund, Sweden
| | - Pär Söderhjelm
- Division of Biophysical Chemistry, Lund University, Chemical Center, 22100 Lund, Sweden
| |
Collapse
|
6
|
Tran P, Crawford T, Ragnarsson L, Deuis JR, Mobli M, Sharpe SJ, Schroeder CI, Vetter I. Structural Conformation and Activity of Spider-Derived Inhibitory Cystine Knot Peptide Pn3a Are Modulated by pH. ACS OMEGA 2023; 8:26276-26286. [PMID: 37521635 PMCID: PMC10373202 DOI: 10.1021/acsomega.3c02664] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 06/22/2023] [Indexed: 08/01/2023]
Abstract
Numerous spider venom-derived gating modifier toxins exhibit conformational heterogeneity during purification by reversed-phase high-performance liquid chromatography (RP-HPLC). This conformational exchange is especially peculiar for peptides containing an inhibitor cystine knot motif, which confers excellent structural stability under conditions that are not conducive to disulfide shuffling. This phenomenon is often attributed to proline cis/trans isomerization but has also been observed in peptides that do not contain a proline residue. Pn3a is one such peptide forming two chromatographically distinguishable peaks that readily interconvert following the purification of either conformer. The nature of this exchange was previously uncharacterized due to the fast rate of conversion in solution, making isolation of the conformers impossible. In the present study, an N-terminal modification of Pn3a enabled the isolation of the individual conformers, allowing activity assays to be conducted on the individual conformers using electrophysiology. The conformers were analyzed separately by nuclear magnetic resonance spectroscopy (NMR) to study their structural differences. RP-HPLC and NMR were used to study the mechanism of exchange. The later-eluting conformer was the active conformer with a rigid structure that corresponds to the published structure of Pn3a, while NMR analysis revealed the earlier-eluting conformer to be inactive and disordered. The exchange was found to be pH-dependent, arising in acidic solutions, possibly due to reversible disruption and formation of intramolecular salt bridges. This study reveals the nature of non-proline conformational exchange observed in Pn3a and possibly other disulfide-rich peptides, highlighting that the structure and activity of some disulfide-stabilized peptides can be dramatically susceptible to disruption.
Collapse
Affiliation(s)
- Poanna Tran
- Institute
for Molecular Bioscience, The University
of Queensland, Brisbane, Queensland 4072, Australia
| | - Theo Crawford
- Centre
for Advanced Imaging, The University of
Queensland, Brisbane, Queensland 4072, Australia
| | - Lotten Ragnarsson
- Institute
for Molecular Bioscience, The University
of Queensland, Brisbane, Queensland 4072, Australia
| | - Jennifer R. Deuis
- Institute
for Molecular Bioscience, The University
of Queensland, Brisbane, Queensland 4072, Australia
| | - Mehdi Mobli
- Centre
for Advanced Imaging, The University of
Queensland, Brisbane, Queensland 4072, Australia
| | - Simon J. Sharpe
- Molecular
Medicine Program, Research Institute, The
Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
- Department
of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Christina I. Schroeder
- Institute
for Molecular Bioscience, The University
of Queensland, Brisbane, Queensland 4072, Australia
- Center
for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, Maryland 21702-1201, United States
- Genentech, 1 DNA Way, South San Francisco, California 94080, United States
| | - Irina Vetter
- Institute
for Molecular Bioscience, The University
of Queensland, Brisbane, Queensland 4072, Australia
- School
of Pharmacy, The University of Queensland, Brisbane, Queensland 4102, Australia
| |
Collapse
|
7
|
Rodgers A, Sawaged M, Ostrovsky D, Vugmeyster L. Effect of Cross-Seeding of Wild-Type Amyloid-β 1-40 Peptides with Post-translationally Modified Fibrils on Internal Dynamics of the Fibrils Using Deuterium Solid-State NMR. J Phys Chem B 2023; 127:2887-2899. [PMID: 36952330 PMCID: PMC10257444 DOI: 10.1021/acs.jpcb.2c07817] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/24/2023]
Abstract
Post-translationally modified (PTM) amyloid-β (Aβ) species can play an important role in modulating Alzheimer's disease pathology. These relatively less populated modifications can cross-seed the wild-type Aβ peptides to produce fibrils that retain many structural and functional features of the original PTM variants. We focus on studies of internal flexibility in the cross-seeded Aβ1-40 fibrils originating from seeding with two PTM variants with modifications in the disordered N-terminal domain: ΔE3 truncation and S8-phosphorylation. We employ an array of 2H solid-state NMR techniques, including line shape analysis over a broad temperature range, longitudinal relaxation, and quadrupolar CPMG, to assess the dynamics of the cross-seeded fibrils. The focus is placed on selected side-chain sites in the disordered N-terminal domain (G9 and V12) and hydrophobic core methyl and aromatic groups (L17, L34, M35, V36, and F19). We find that many of the essential features of the dynamics present in the original PTM seeds persist in the cross-seeded fibrils, and several of the characteristic features are even enhanced. This is particularly true for the activation energies of the rotameric motions and large-scale rearrangements of the N-terminal domain. Thus, our results on the dynamics complement prior structural and cell toxicity studies, suggesting that many PTM Aβ species can aggressively cross-seed the wild-type peptide in a manner that propagates the PTM's signature.
Collapse
Affiliation(s)
- Aryana Rodgers
- Department of Chemistry, University of Colorado Denver, Denver CO USA 80204
| | - Matthew Sawaged
- Department of Chemistry, University of Colorado Denver, Denver CO USA 80204
| | - Dmitry Ostrovsky
- Department of Mathematics, University of Colorado Denver, Denver CO USA 80204
| | - Liliya Vugmeyster
- Department of Chemistry, University of Colorado Denver, Denver CO USA 80204
| |
Collapse
|
8
|
Akke M, Weininger U. NMR Studies of Aromatic Ring Flips to Probe Conformational Fluctuations in Proteins. J Phys Chem B 2023; 127:591-599. [PMID: 36640108 PMCID: PMC9884080 DOI: 10.1021/acs.jpcb.2c07258] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Revised: 12/25/2022] [Indexed: 01/15/2023]
Abstract
Aromatic residues form a significant part of the protein core, where they make tight interactions with multiple surrounding side chains. Despite the dense packing of internal side chains, the aromatic rings of phenylalanine and tyrosine residues undergo 180° rotations, or flips, which are mediated by transient and large-scale "breathing" motions that generate sufficient void volume around the aromatic ring. Forty years after the seminal work by Wagner and Wüthrich, NMR studies of aromatic ring flips are now undergoing a renaissance as a powerful means of probing fundamental dynamic properties of proteins. Recent developments of improved NMR methods and isotope labeling schemes have enabled a number of advances in addressing the mechanisms and energetics of aromatic ring flips. The nature of the transition states associated with ring flips can be described by thermodynamic activation parameters, including the activation enthalpy, activation entropy, activation volume, and also the isothermal volume compressibility of activation. Consequently, it is of great interest to study how ring flip rate constants and activation parameters might vary with protein structure and external conditions like temperature and pressure. The field is beginning to gather such data for aromatic residues in a variety of environments, ranging from surface exposed to buried. In the future, the combination of solution and solid-state NMR spectroscopy together with molecular dynamics simulations and other computational approaches is likely to provide detailed information about the coupled dynamics of aromatic rings and neighboring residues. In this Perspective, we highlight recent developments and provide an outlook toward the future.
Collapse
Affiliation(s)
- Mikael Akke
- Division
of Biophysical Chemistry, Center for Molecular Protein Science, Department
of Chemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
| | - Ulrich Weininger
- Institute
of Physics, Biophysics, Martin-Luther-University
Halle-Wittenberg, D-06129 Halle (Saale), Germany
| |
Collapse
|
9
|
Ferré G, Anazia K, Silva LO, Thakur N, Ray AP, Eddy MT. Global insights into the fine tuning of human A 2AAR conformational dynamics in a ternary complex with an engineered G protein viewed by NMR. Cell Rep 2022; 41:111844. [PMID: 36543140 PMCID: PMC9832913 DOI: 10.1016/j.celrep.2022.111844] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 11/03/2022] [Accepted: 11/24/2022] [Indexed: 12/24/2022] Open
Abstract
G protein-coupled receptor (GPCR) conformational plasticity enables formation of ternary signaling complexes with intracellular proteins in response to binding extracellular ligands. We investigate the dynamic process of GPCR complex formation in solution with the human A2A adenosine receptor (A2AAR) and an engineered Gs protein, mini-Gs. 2D nuclear magnetic resonance (NMR) data with uniform stable isotope-labeled A2AAR enabled a global comparison of A2AAR conformations between complexes with an agonist and mini-Gs and with an agonist alone. The two conformations are similar and show subtle differences at the receptor intracellular surface, supporting a model whereby agonist binding alone is sufficient to populate a conformation resembling the active state. However, an A2AAR "hot spot" connecting the extracellular ligand-binding pocket to the intracellular surface is observed to be highly dynamic in the ternary complex, suggesting a mechanism for allosteric connection between the bound G protein and the drug-binding pocket involving structural plasticity of the "toggle switch" tryptophan.
Collapse
Affiliation(s)
- Guillaume Ferré
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Kara Anazia
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Larissa O Silva
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Naveen Thakur
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Arka P Ray
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA
| | - Matthew T Eddy
- Department of Chemistry, University of Florida, Gainesville, FL 32611, USA.
| |
Collapse
|
10
|
Gauto DF, Lebedenko OO, Becker LM, Ayala I, Lichtenecker R, Skrynnikov NR, Schanda P. Aromatic ring flips in differently packed ubiquitin protein crystals from MAS NMR and MD. J Struct Biol X 2022; 7:100079. [PMID: 36578472 PMCID: PMC9791609 DOI: 10.1016/j.yjsbx.2022.100079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Probing the dynamics of aromatic side chains provides important insights into the behavior of a protein because flips of aromatic rings in a protein's hydrophobic core report on breathing motion involving a large part of the protein. Inherently invisible to crystallography, aromatic motions have been primarily studied by solution NMR. The question how packing of proteins in crystals affects ring flips has, thus, remained largely unexplored. Here we apply magic-angle spinning NMR, advanced phenylalanine 1H-13C/2H isotope labeling and MD simulation to a protein in three different crystal packing environments to shed light onto possible impact of packing on ring flips. The flips of the two Phe residues in ubiquitin, both surface exposed, appear remarkably conserved in the different crystal forms, even though the intermolecular packing is quite different: Phe4 flips on a ca. 10-20 ns time scale, and Phe45 are broadened in all crystals, presumably due to µs motion. Our findings suggest that intramolecular influences are more important for ring flips than intermolecular (packing) effects.
Collapse
Affiliation(s)
- Diego F. Gauto
- Univ. Grenoble Alpes, CEA, CNRS, Institut de Biologie Structurale (IBS), 71, Avenue des Martyrs, F-38044 Grenoble, France
- ICSN, CNRS UPR2301, Univ. Paris-Saclay, Gif-sur-Yvette, France
| | - Olga O. Lebedenko
- Laboratory of Biomolecular NMR, St. Petersburg State University, St. Petersburg 199034, Russia
| | - Lea Marie Becker
- Institute of Science and Technology Austria, Am Campus 1, A-3400 Klosterneuburg, Austria
| | - Isabel Ayala
- Univ. Grenoble Alpes, CEA, CNRS, Institut de Biologie Structurale (IBS), 71, Avenue des Martyrs, F-38044 Grenoble, France
| | - Roman Lichtenecker
- Institute of Organic Chemistry, University of Vienna, Waehringer Str. 38, 1090 Vienna, Austria
| | - Nikolai R. Skrynnikov
- Laboratory of Biomolecular NMR, St. Petersburg State University, St. Petersburg 199034, Russia
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN 47907-2084, USA
| | - Paul Schanda
- Institute of Science and Technology Austria, Am Campus 1, A-3400 Klosterneuburg, Austria
| |
Collapse
|
11
|
Dreydoppel M, Akke M, Weininger U. Characterizing Fast Conformational Exchange of Aromatic Rings Using Residual Dipolar Couplings: Distinguishing Jumplike Flips from Other Exchange Mechanisms. J Phys Chem B 2022; 126:7950-7956. [PMID: 36180044 PMCID: PMC9574926 DOI: 10.1021/acs.jpcb.2c05097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Aromatic ring flips are a hallmark of protein dynamics.
They are
experimentally studied by NMR spectroscopy, where recent advances
have led to improved characterization across a wide range of time
scales. Results on different proteins have been interpreted as continuous
diffusive ring rotations or jumplike flips, leading to diverging views
of the protein interior as being fluidlike or solidlike, respectively.
It is challenging to distinguish between these mechanisms and other
types of conformational exchange because chemical-shift-mediated line
broadening provides only conclusive evidence for ring flips only if
the system can be moved from the slow- to intermediate/fast-exchange
regime. Moreover, whenever the chemical shift difference between the
two symmetry-related sites is close to zero, it is not generally possible
to determine the exchange time scale. Here we resolve these issues
by measuring residual dipolar coupling (RDC)-mediated exchange contributions
using NMR relaxation dispersion experiments on proteins dissolved
in dilute liquid crystalline media. Excellent agreement is found between
the experimental difference in RDC between the two symmetry-related
sites and the value calculated from high-resolution X-ray structures,
demonstrating that dynamics measured for F52 in the B1 domain of protein
G reports on distinct, jumplike flips rather than other types of conformational
exchange.
Collapse
Affiliation(s)
- Matthias Dreydoppel
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, D-06120Halle (Saale), Germany
| | - Mikael Akke
- Division of Biophysical Chemistry, Center for Molecular Protein Science, Department of Chemistry, Lund University, P.O. Box 124, SE-22100Lund, Sweden
| | - Ulrich Weininger
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, D-06120Halle (Saale), Germany
| |
Collapse
|
12
|
Shah AA, Amjad M, Hassan JU, Ullah A, Mahmood A, Deng H, Ali Y, Gul F, Xia K. Molecular Insights into the Role of Pathogenic nsSNPs in GRIN2B Gene Provoking Neurodevelopmental Disorders. Genes (Basel) 2022; 13:genes13081332. [PMID: 35893069 PMCID: PMC9394290 DOI: 10.3390/genes13081332] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/11/2022] [Accepted: 07/20/2022] [Indexed: 12/04/2022] Open
Abstract
The GluN2B subunit of N-methyl-D-aspartate receptors plays an important role in the physiology of different neurodevelopmental diseases. Genetic variations in the GluN2B coding gene (GRIN2B) have consistently been linked to West syndrome, intellectual impairment with focal epilepsy, developmental delay, macrocephaly, corticogenesis, brain plasticity, as well as infantile spasms and Lennox–Gastaut syndrome. It is unknown, however, how GRIN2B genetic variation impacts protein function. We determined the cumulative pathogenic impact of GRIN2B variations on healthy participants using a computational approach. We looked at all of the known mutations and calculated the impact of single nucleotide polymorphisms on GRIN2B, which encodes the GluN2B protein. The pathogenic effect, functional impact, conservation analysis, post-translation alterations, their driving residues, and dynamic behaviors of deleterious nsSNPs on protein models were then examined. Four polymorphisms were identified as phylogenetically conserved PTM drivers and were related to structural and functional impact: rs869312669 (p.Thr685Pro), rs387906636 (p.Arg682Cys), rs672601377 (p.Asn615Ile), and rs1131691702 (p.Ser526Pro). The combined impact of protein function is accounted for by the calculated stability, compactness, and total globularity score. GluN2B hydrogen occupancy was positively associated with protein stability, and solvent-accessible surface area was positively related to globularity. Furthermore, there was a link between GluN2B protein folding, movement, and function, indicating that both putative high and low local movements were linked to protein function. Multiple GRIN2B genetic variations are linked to gene expression, phylogenetic conservation, PTMs, and protein instability behavior in neurodevelopmental diseases. These findings suggest the relevance of GRIN2B genetic variations in neurodevelopmental problems.
Collapse
Affiliation(s)
- Abid Ali Shah
- Center for Medical Genetics and Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha 410013, China; (A.A.S.); (A.M.)
| | - Marryam Amjad
- District Headquarter (DHQ) Hospital, Faisalabad 38000, Punjab, Pakistan;
| | | | - Asmat Ullah
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark;
| | - Arif Mahmood
- Center for Medical Genetics and Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha 410013, China; (A.A.S.); (A.M.)
| | - Huiyin Deng
- Department of Anesthesiology, The Third Xiangya Hospital of Central South University, Changsha 410013, China;
| | - Yasir Ali
- National Center for Bioinformatics, Quaid-i-Azam University, Islamabad 45320, Pakistan; (Y.A.); (F.G.)
| | - Fouzia Gul
- National Center for Bioinformatics, Quaid-i-Azam University, Islamabad 45320, Pakistan; (Y.A.); (F.G.)
| | - Kun Xia
- Center for Medical Genetics and Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha 410013, China; (A.A.S.); (A.M.)
- Hengyang Medical School, University of South China, Hengyang 421000, China
- CAS Center for Excellence in Brain Science and Intelligences Technology (CEBSIT), Chinese Academy of Sciences, Shanghai 200030, China
- Correspondence: ; Tel.: +86-731-8480-5357
| |
Collapse
|
13
|
GPCR large-amplitude dynamics by 19F-NMR of aprepitant bound to the neurokinin 1 receptor. Proc Natl Acad Sci U S A 2022; 119:e2122682119. [PMID: 35377814 PMCID: PMC9169749 DOI: 10.1073/pnas.2122682119] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Comparisons of G protein-coupled receptor (GPCR) complexes with agonists and antagonists based on X-ray crystallography and cryo-electron microscopy structure determinations show differences in the width of the orthosteric ligand binding groove over the range from 0.3 to 2.9 Å. Here, we show that there are transient structure fluctuations with amplitudes up to at least 6 Å. The experiments were performed with the neurokinin 1 receptor (NK1R), a GPCR of class A that is involved in inflammation, pain, and cancer. We used 19F-NMR observation of aprepitant, which is an approved drug that targets NK1R for the treatment of chemotherapy-induced nausea and vomiting. Aprepitant includes a bis-trifluoromethyl-phenyl ring attached with a single bond to the core of the molecule; 19F-NMR revealed 180° flipping motions of this ring about this bond. In the picture emerging from the 19F-NMR data, the GPCR transmembrane helices undergo large-scale floating motions in the lipid bilayer. The functional implication is of extensive promiscuity of initial ligand binding, primarily determined by size and shape of the ligand, with subsequent selection by unique interactions between atom groups of the ligand and the GPCR within the binding groove. This second step ensures the wide range of different efficacies documented for GPCR-targeting drugs. The NK1R data also provide a rationale for the observation that diffracting GPCR crystals are obtained for complexes with only very few of the ligands from libraries of approved drugs and lead compounds that bind to the receptors.
Collapse
|
14
|
Wei S, Thakur N, Ray AP, Jin B, Obeng S, McCurdy CR, McMahon LR, Gutiérrez-de-Terán H, Eddy MT, Lamichhane R. Slow conformational dynamics of the human A 2A adenosine receptor are temporally ordered. Structure 2022; 30:329-337.e5. [PMID: 34895472 PMCID: PMC8897252 DOI: 10.1016/j.str.2021.11.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 09/26/2021] [Accepted: 11/17/2021] [Indexed: 01/12/2023]
Abstract
A more complete depiction of protein energy landscapes includes the identification of different function-related conformational states and the determination of the pathways connecting them. We used total internal reflection fluorescence (TIRF) imaging to investigate the conformational dynamics of the human A2A adenosine receptor (A2AAR), a class A G protein-coupled receptor (GPCR), at the single-molecule level. Slow, reversible conformational exchange was observed among three different fluorescence emission states populated for agonist-bound A2AAR. Transitions among these states predominantly occurred in a specific order, and exchange between inactive and active-like conformations proceeded through an intermediate state. Models derived from molecular dynamics simulations with available A2AAR structures rationalized the relative fluorescence emission intensities for the highest and lowest emission states but not the transition state. This suggests that the functionally critical intermediate state required to achieve activation is not currently visualized among available A2AAR structures.
Collapse
Affiliation(s)
- Shushu Wei
- Department of Biochemistry & Cellular and Molecular Biology, College of Arts and Sciences, University of Tennessee, 1311 Cumberland Avenue, Knoxville, TN 37932, USA
| | - Naveen Thakur
- Department of Chemistry, College of Liberal Arts and Sciences, University of Florida, 126 Sisler Hall, Gainesville, FL 32611, USA
| | - Arka P Ray
- Department of Chemistry, College of Liberal Arts and Sciences, University of Florida, 126 Sisler Hall, Gainesville, FL 32611, USA
| | - Beining Jin
- Department of Chemistry, College of Liberal Arts and Sciences, University of Florida, 126 Sisler Hall, Gainesville, FL 32611, USA
| | - Samuel Obeng
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL 32610, USA; Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, FL 32610, USA
| | - Christopher R McCurdy
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, FL 32610, USA; Translational Drug Development Core, Clinical and Translational Sciences Institute, University of Florida, Gainesville, FL 32610, USA
| | - Lance R McMahon
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL 32610, USA
| | - Hugo Gutiérrez-de-Terán
- Department of Cell and Molecular Biology, Uppsala University, B.M.C., Box 596, Uppsala 751 24, Sweden
| | - Matthew T Eddy
- Department of Chemistry, College of Liberal Arts and Sciences, University of Florida, 126 Sisler Hall, Gainesville, FL 32611, USA.
| | - Rajan Lamichhane
- Department of Biochemistry & Cellular and Molecular Biology, College of Arts and Sciences, University of Tennessee, 1311 Cumberland Avenue, Knoxville, TN 37932, USA.
| |
Collapse
|
15
|
Vugmeyster L, Au DF, Smith MC, Ostrovsky D. Comparative Hydrophobic Core Dynamics Between Wild-Type Amyloid-β Fibrils, Glutamate-3 Truncation, and Serine-8 Phosphorylation. Chemphyschem 2022; 23:e202100709. [PMID: 34837296 PMCID: PMC9484291 DOI: 10.1002/cphc.202100709] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/10/2021] [Indexed: 02/06/2023]
Abstract
Post-translational modifications (PTMs) of amyloid-β (Aβ) species are implicated in the modulation of overall toxicities and aggregation propensities. We investigated the internal dynamics in the hydrophobic core of the truncated ΔE3 mutant fibrils of Aβ1-40 and compared them with prior and new data for wild-type fibrils as well as with phosphorylated S8 fibrils. Deuteron static solid-state NMR techniques, spanning line-shape analysis, longitudinal relaxation, and chemical exchange saturation transfer methods, were employed to assess the rotameric jumps of several methyl-bearing and aromatic groups in the core of the fibrils. Taken together, the results indicate the rather significant influence of the PTMs on the hydrophobic core dynamics, which propagates far beyond the local site of the chemical modification. The phosphorylated S8 fibrils display an overall rigidifying of the core based on the higher activation barriers of motions than the wild-type fibrils, whereas the ΔE3 fibrils induce a broader variety of changes, some of which are thermodynamic in nature rather than the kinetic ones.
Collapse
Affiliation(s)
- Liliya Vugmeyster
- Department of Chemistry, University of Colorado Denver, Denver CO USA 80204
| | - Dan Fai Au
- Department of Chemistry, University of Colorado Denver, Denver CO USA 80204
| | - Matthew C. Smith
- Department of Chemistry, University of Colorado Denver, Denver CO USA 80204
| | - Dmitry Ostrovsky
- Department of Mathematics, University of Colorado Denver, Denver CO USA 80204
| |
Collapse
|
16
|
Mariño Pérez L, Ielasi FS, Bessa LM, Maurin D, Kragelj J, Blackledge M, Salvi N, Bouvignies G, Palencia A, Jensen MR. Visualizing protein breathing motions associated with aromatic ring flipping. Nature 2022; 602:695-700. [PMID: 35173330 PMCID: PMC8866124 DOI: 10.1038/s41586-022-04417-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 01/07/2022] [Indexed: 01/11/2023]
Abstract
Aromatic residues cluster in the core of folded proteins, where they stabilize the structure through multiple interactions. Nuclear magnetic resonance (NMR) studies in the 1970s showed that aromatic side chains can undergo ring flips-that is, 180° rotations-despite their role in maintaining the protein fold1-3. It was suggested that large-scale 'breathing' motions of the surrounding protein environment would be necessary to accommodate these ring flipping events1. However, the structural details of these motions have remained unclear. Here we uncover the structural rearrangements that accompany ring flipping of a buried tyrosine residue in an SH3 domain. Using NMR, we show that the tyrosine side chain flips to a low-populated, minor state and, through a proteome-wide sequence analysis, we design mutants that stabilize this state, which allows us to capture its high-resolution structure by X-ray crystallography. A void volume is generated around the tyrosine ring during the structural transition between the major and minor state, and this allows fast flipping to take place. Our results provide structural insights into the protein breathing motions that are associated with ring flipping. More generally, our study has implications for protein design and structure prediction by showing how the local protein environment influences amino acid side chain conformations and vice versa.
Collapse
Affiliation(s)
- Laura Mariño Pérez
- Université Grenoble Alpes, CEA, CNRS, IBS, Grenoble, France
- Departament de Química, Universitat de les Illes Balears, Palma de Mallorca, Spain
| | - Francesco S Ielasi
- Institute for Advanced Biosciences (IAB), Structural Biology of Novel Targets in Human Diseases, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
| | - Luiza M Bessa
- Université Grenoble Alpes, CEA, CNRS, IBS, Grenoble, France
| | - Damien Maurin
- Université Grenoble Alpes, CEA, CNRS, IBS, Grenoble, France
| | - Jaka Kragelj
- Université Grenoble Alpes, CEA, CNRS, IBS, Grenoble, France
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | | | - Nicola Salvi
- Université Grenoble Alpes, CEA, CNRS, IBS, Grenoble, France
| | - Guillaume Bouvignies
- Laboratoire des Biomolécules (LBM), Département de Chimie, École normale supérieure, PSL University, Sorbonne Université, CNRS, Paris, France
| | - Andrés Palencia
- Institute for Advanced Biosciences (IAB), Structural Biology of Novel Targets in Human Diseases, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France.
| | | |
Collapse
|
17
|
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.
Collapse
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.
| |
Collapse
|
18
|
Horx P, Geyer A. High five! Methyl probes at five ring positions of phenylalanine explore the hydrophobic core dynamics of zinc finger miniproteins. Chem Sci 2021; 12:11455-11463. [PMID: 34667551 PMCID: PMC8447250 DOI: 10.1039/d1sc02346b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 07/22/2021] [Indexed: 12/02/2022] Open
Abstract
The elucidation of internal dynamics in proteins is essential for the understanding of their stability and functionality. Breaking the symmetry of the degenerate rotation of the phenyl side chain provides additional structural information and allows a detailed description of the dynamics. Based on this concept, we propose a combination of synthetic and computational methods, to study the rotational mobility of the Phe ring in a sensitive zinc finger motif. The systematic methyl hopping around the phenylalanine ring yields o-, m-, p-tolyl and xylyl side chains that provide a vast array of additional NOE contacts, allowing the precise determination of the orientation of the aromatic ring. MD simulations and metadynamics complement these findings and facilitate the generation of free energy profiles for each derivative. Previous studies used a wide temperature window in combination with NMR spectroscopy to elucidate the side chain mobility of stable proteins. The zinc finger moiety exhibits a limited thermodynamic stability in a temperature range of only 40 K, making this approach impractical for this compound class. Therefore, we have developed a method that can be applied even to thermolabile systems and facilitates the detailed investigation of protein dynamics.
Collapse
Affiliation(s)
- Philip Horx
- Philipps-University Marburg 35043 Marburg Germany
| | - Armin Geyer
- Philipps-University Marburg 35043 Marburg Germany
| |
Collapse
|
19
|
Young BM, Rossi P, Slavish PJ, Cui Y, Sowaileh M, Das J, Kalodimos CG, Rankovic Z. Synthesis of Isotopically Labeled, Spin-Isolated Tyrosine and Phenylalanine for Protein NMR Applications. Org Lett 2021; 23:6288-6292. [PMID: 34379431 PMCID: PMC8884888 DOI: 10.1021/acs.orglett.1c02084] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Isotopically labeled
amino acids are widely used to study the structure
and dynamics of proteins by NMR. Herein we describe a facile, gram-scale
synthesis of compounds 1b and 2b under standard
laboratory conditions from the common intermediate 7. 2b is obtained via simple deprotection, while 1b is accessed through a reductive deoxygenation/deuteration sequence
and deprotection. 1b and 2b provide improved
signal intensity using lower amounts of labeled precursor and are
alternatives to existing labeling approaches.
Collapse
Affiliation(s)
- Brandon M Young
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, United States
| | - Paolo Rossi
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, United States
| | - P Jake Slavish
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, United States
| | - Yixin Cui
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, United States
| | - Munia Sowaileh
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, United States
| | - Jitendra Das
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, United States
| | - Charalampos G Kalodimos
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, United States
| | - Zoran Rankovic
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, United States
| |
Collapse
|
20
|
Dreydoppel M, Dorn B, Modig K, Akke M, Weininger U. Transition-State Compressibility and Activation Volume of Transient Protein Conformational Fluctuations. JACS AU 2021; 1:833-842. [PMID: 34467336 PMCID: PMC8395657 DOI: 10.1021/jacsau.1c00062] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Indexed: 06/13/2023]
Abstract
Proteins are dynamic entities that intermittently depart from their ground-state structures and undergo conformational transitions as a critical part of their functions. Central to understanding such transitions are the structural rearrangements along the connecting pathway, where the transition state plays a special role. Using NMR relaxation at variable temperature and pressure to measure aromatic ring flips inside a protein core, we obtain information on the structure and thermodynamics of the transition state. We show that the isothermal compressibility coefficient of the transition state is similar to that of short-chain hydrocarbon liquids, implying extensive local unfolding of the protein. Our results further indicate that the required local volume expansions of the protein can occur not only with a net positive activation volume of the protein, as expected from previous studies, but also with zero activation volume by compaction of remote void volume, when averaged over the ensemble of states.
Collapse
Affiliation(s)
- Matthias Dreydoppel
- Institute
of Physics, Biophysics, Martin-Luther-University
Halle-Wittenberg, D-06120 Halle (Saale), Germany
| | - Britta Dorn
- Institute
of Physics, Biophysics, Martin-Luther-University
Halle-Wittenberg, D-06120 Halle (Saale), Germany
| | - Kristofer Modig
- Division
of Biophysical Chemistry, Center for Molecular Protein Science, Department
of Chemistry, Lund University, P.O. Box 124, SE-22100 Lund, Sweden
| | - Mikael Akke
- Division
of Biophysical Chemistry, Center for Molecular Protein Science, Department
of Chemistry, Lund University, P.O. Box 124, SE-22100 Lund, Sweden
| | - Ulrich Weininger
- Institute
of Physics, Biophysics, Martin-Luther-University
Halle-Wittenberg, D-06120 Halle (Saale), Germany
| |
Collapse
|
21
|
Martin BT, Malmstrom RD, Amaro RE, Wüthrich K. OCRE Domains of Splicing Factors RBM5 and RBM10: Tyrosine Ring-Flip Frequencies Determined by Integrated Use of 1 H NMR Spectroscopy and Molecular Dynamics Simulations. Chembiochem 2020; 22:565-570. [PMID: 32975902 DOI: 10.1002/cbic.202000517] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 09/18/2020] [Indexed: 11/12/2022]
Abstract
The 55-residue OCRE domains of the splicing factors RBM5 and RBM10 contain 15 tyrosines in compact, globular folds. At 25 °C, all 15 tyrosines show symmetric 1 H NMR spectra, with averaged signals for the pairs of δ- and ϵ-ring hydrogens. At 4 °C, two tyrosines were identified as showing 1 H NMR line-broadening due to lowered frequency of the ring-flipping. For the other 13 tyrosine rings, it was not evident, from the 1 H NMR data alone, whether they were either all flipping at high frequencies, or whether slowed flipping went undetected due to small chemical-shift differences between pairs of exchanging ring hydrogen atoms. Here, we integrate 1 H NMR spectroscopy and molecular dynamics (MD) simulations to determine the tyrosine ring-flip frequencies. In the RBM10-OCRE domain, we found that, for 11 of the 15 tyrosines, these frequencies are in the range 2.0×106 to 1.3×108 s-1 , and we established an upper limit of <1.0×106 s-1 for the remaining four residues. The experimental data and the MD simulation are mutually supportive, and their combined use extends the analysis of aromatic ring-flip events beyond the limitations of routine 1 H NMR line-shape analysis into the nanosecond frequency range.
Collapse
Affiliation(s)
- Bryan T Martin
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, MB 44, La Jolla, CA 92037, USA.,Present address: Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Robert D Malmstrom
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093, USA.,National Biomedical Computation Resource, University of California, San Diego, La Jolla, CA 92093, USA.,5820 Nancy Ridge Drive, San Diego, CA 92121, USA
| | - Rommie E Amaro
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093, USA.,National Biomedical Computation Resource, University of California, San Diego, La Jolla, CA 92093, USA
| | - Kurt Wüthrich
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, MB 44, La Jolla, CA 92037, USA.,Institute for Molecular Biology and Biophysics, ETH Zürich, Zürich, Switzerland
| |
Collapse
|
22
|
Kahler U, Kamenik AS, Waibl F, Kraml J, Liedl KR. Protein-Protein Binding as a Two-Step Mechanism: Preselection of Encounter Poses during the Binding of BPTI and Trypsin. Biophys J 2020; 119:652-666. [PMID: 32697976 PMCID: PMC7399559 DOI: 10.1016/j.bpj.2020.06.032] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 06/16/2020] [Accepted: 06/29/2020] [Indexed: 11/04/2022] Open
Abstract
Biomolecular recognition between proteins follows complex mechanisms, the understanding of which can substantially advance drug discovery efforts. Here, we track each step of the binding process in atomistic detail with molecular dynamics simulations using trypsin and its inhibitor bovine pancreatic trypsin inhibitor (BPTI) as a model system. We use umbrella sampling to cover a range of unbinding pathways. Starting from these simulations, we subsequently seed classical simulations at different stages of the process and combine them to a Markov state model. We clearly identify three kinetically separated states (an unbound state, an encounter state, and the final complex) and describe the mechanisms that dominate the binding process. From our model, we propose the following sequence of events. The initial formation of the encounter complex is driven by long-range interactions because opposite charges in trypsin and BPTI draw them together. The encounter complex features the prealigned binding partners with binding sites still partially surrounded by solvation shells. Further approaching leads to desolvation and increases the importance of van der Waals interactions. The native binding pose is adopted by maximizing short-range interactions. Thereby side-chain rearrangements ensure optimal shape complementarity. In particular, BPTI’s P1 residue adapts to the S1 pocket and prime site residues reorient to optimize interactions. After the paradigm of conformation selection, binding-competent conformations of BPTI and trypsin are already present in the apo ensembles and their probabilities increase during this proposed two-step association process. This detailed characterization of the molecular forces driving the binding process includes numerous aspects that have been discussed as central to the binding of trypsin and BPTI and protein complex formation in general. In this study, we combine all these aspects into one comprehensive model of protein recognition. We thereby contribute to enhance our general understanding of this fundamental mechanism, which is particularly critical as the development of biopharmaceuticals continuously gains significance.
Collapse
Affiliation(s)
- Ursula Kahler
- Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck, Innsbruck, Austria
| | - Anna S Kamenik
- Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck, Innsbruck, Austria
| | - Franz Waibl
- Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck, Innsbruck, Austria
| | - Johannes Kraml
- Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck, Innsbruck, Austria
| | - Klaus R Liedl
- Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck, Innsbruck, Austria.
| |
Collapse
|
23
|
Dreydoppel M, Raum HN, Weininger U. Slow ring flips in aromatic cluster of GB1 studied by aromatic 13C relaxation dispersion methods. JOURNAL OF BIOMOLECULAR NMR 2020; 74:183-191. [PMID: 32016706 PMCID: PMC7080667 DOI: 10.1007/s10858-020-00303-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 01/27/2020] [Indexed: 06/10/2023]
Abstract
Ring flips of phenylalanine and tyrosine are a hallmark of protein dynamics. They report on transient breathing motions of proteins. In addition, flip rates also depend on stabilizing interactions in the ground state, like aromatic stacking or cation-π interaction. So far, experimental studies of ring flips have almost exclusively been performed on aromatic rings without stabilizing interactions. Here we investigate ring flip dynamics of Phe and Tyr in the aromatic cluster in GB1. We found that all four residues of the cluster, Y3, F30, Y45 and F52, display slow ring flips. Interestingly, F52, the central residue of the cluster, which makes aromatic contacts with all three others, is flipping significantly faster, while the other rings are flipping with the same rates within margin of error. Determined activation enthalpies and activation volumes of these processes are in the same range of other reported ring flips of single aromatic rings. There is no correlation of the number of aromatic stacking interactions to the activation enthalpy, and no correlation of the ring's extent of burying to the activation volume. Because of these findings, we speculate that F52 is undergoing concerted ring flips with each of the other rings.
Collapse
Affiliation(s)
- Matthias Dreydoppel
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, 06120, Halle (Saale), Germany
| | - Heiner N Raum
- 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.
| |
Collapse
|
24
|
Al Mehdi K, Fouad B, Zouhair E, Boutaina B, Yassine N, Chaimaa AEC, Najat S, Hassan R, Rachida R, Abdelhamid B, Halima N. Molecular Modelling and Dynamics Study of nsSNP in STXBP1 Gene in Early Infantile Epileptic Encephalopathy Disease. BIOMED RESEARCH INTERNATIONAL 2019; 2019:4872101. [PMID: 31976320 PMCID: PMC6955126 DOI: 10.1155/2019/4872101] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 08/12/2019] [Accepted: 08/20/2019] [Indexed: 02/02/2023]
Abstract
Early Infantile Epileptic Encephalopathy (known as Ohtahara Syndrome) is one of the most severe and earliest forms of epilepsy, characterized by early seizures onset. It affects newborns and children between two and six years old. Among the genes that have been associated with early infantile epileptic encephalopathy, the STXBP1 gene, which encodes the Syntaxin binding protein1a that is involved in SNARE complex formation, contributes to synaptic vesicles exocytosis. The aim of this study was to identify the most pathogenic polymorphisms of STXBP1 gene and determine their impact on the structure and stability of Stxbp1 protein. The high-risk nonsynonymous single nucleotide polymorphisms (nsSNPs) in the STXBP1 gene were predicted using 13 bioinformatics tools. The conservation analysis was realized by CONSURF web server. The analysis of the impact of the pathogenic SNPs on the structure of Stxbp1 protein was realized using YASARA software, and the molecular dynamics simulation was performed using GROMACS software. Out of 245 nsSNPs, we identified 11 (S42P, H103D R190W, R235G, D238E, L256P, P335S, C354Y, L365V, R406C, and G544D) as deleterious using in silico prediction tools. Conservation analysis results revealed that all these nsSNPs were located in conserved regions. The comparison of the hydrogen and hydrophobic interactions in the wild type Stxbp1 structure and its mutant forms showed that all these nsSNPs affect the protein structure on different levels. The molecular dynamics simulations revealed that the total of nsSNPs affect the protein stability, residual fluctuation, and the compaction at different levels. This study provides helpful information on high risk nsSNPs that may affect the Stxbp1 protein structure and function. Thus, these variants should be taken into consideration during the genetic screening of patients suffering from early infantile epileptic encephalopathy.
Collapse
Affiliation(s)
- Krami Al Mehdi
- Laboratory of Genomics and Human Genetics, Institut Pasteur du Maroc, Casablanca 20360, Morocco
- Laboratory of Physiology and Molecular Genetics, Department of Biology, Faculty of Sciences Ain Chock, B.P 5366 Maarif, Casablanca, Morocco
| | - Benhnini Fouad
- Laboratory of Cellular Signaling, Faculty of Sciences Meknes, Moulay Ismail University, Morocco
| | - Elkarhat Zouhair
- Laboratory of Genomics and Human Genetics, Institut Pasteur du Maroc, Casablanca 20360, Morocco
| | - Belkady Boutaina
- Laboratory of Genomics and Human Genetics, Institut Pasteur du Maroc, Casablanca 20360, Morocco
- Laboratory of Physiology and Molecular Genetics, Department of Biology, Faculty of Sciences Ain Chock, B.P 5366 Maarif, Casablanca, Morocco
| | - Naasse Yassine
- Laboratory of Genomics and Human Genetics, Institut Pasteur du Maroc, Casablanca 20360, Morocco
| | - Ait El Cadi Chaimaa
- Laboratory of Genomics and Human Genetics, Institut Pasteur du Maroc, Casablanca 20360, Morocco
| | - Sifeddine Najat
- Laboratory of Genomics and Human Genetics, Institut Pasteur du Maroc, Casablanca 20360, Morocco
- Laboratory of Physiology and Molecular Genetics, Department of Biology, Faculty of Sciences Ain Chock, B.P 5366 Maarif, Casablanca, Morocco
| | - Rouba Hassan
- Laboratory of Genomics and Human Genetics, Institut Pasteur du Maroc, Casablanca 20360, Morocco
| | - Roky Rachida
- Laboratory of Physiology and Molecular Genetics, Department of Biology, Faculty of Sciences Ain Chock, B.P 5366 Maarif, Casablanca, Morocco
| | - Barakat Abdelhamid
- Laboratory of Genomics and Human Genetics, Institut Pasteur du Maroc, Casablanca 20360, Morocco
| | - Nahili Halima
- Laboratory of Genomics and Human Genetics, Institut Pasteur du Maroc, Casablanca 20360, Morocco
| |
Collapse
|
25
|
Raum HN, Schörghuber J, Dreydoppel M, Lichtenecker RJ, Weininger U. Site-selective 1H/ 2H labeling enables artifact-free 1H CPMG relaxation dispersion experiments in aromatic side chains. JOURNAL OF BIOMOLECULAR NMR 2019; 73:633-639. [PMID: 31506857 PMCID: PMC6859156 DOI: 10.1007/s10858-019-00275-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 09/05/2019] [Indexed: 06/10/2023]
Abstract
Aromatic side chains are often key residues in enzyme active sites and protein binding sites, making them attractive probes of protein dynamics on the millisecond timescale. Such dynamic processes can be studied by aromatic 13C or 1H CPMG relaxation dispersion experiments. Aromatic 1H CPMG relaxation dispersion experiments in phenylalanine, tyrosine and the six-ring moiety of tryptophan, however, are affected by 3J 1H-1H couplings which are causing anomalous relaxation dispersion profiles. Here we show that this problem can be addressed by site-selective 1H/2H labeling of the aromatic side chains and that artifact-free relaxation dispersion profiles can be acquired. The method has been further validated by measuring folding-unfolding kinetics of the small protein GB1. The determined rate constants and populations agree well with previous results from 13C CPMG relaxation dispersion experiments. Furthermore, the CPMG-derived chemical shift differences between the folded and unfolded states are in excellent agreement with those obtained directly from the spectra. In summary, site-selective 1H/2H labeling enables artifact-free aromatic 1H CPMG relaxation dispersion experiments in phenylalanine and the six-ring moiety of tryptophan, thereby extending the available methods for studying millisecond dynamics in aromatic protein side chains.
Collapse
Affiliation(s)
- Heiner N Raum
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, 06120, Halle, Germany
| | - Julia Schörghuber
- Institute of Organic Chemistry, University of Vienna, 1090, Vienna, Austria
| | - Matthias Dreydoppel
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, 06120, Halle, Germany
| | | | - Ulrich Weininger
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, 06120, Halle, Germany.
| |
Collapse
|
26
|
Lu M, Ishima R, Polenova T, Gronenborn AM. 19F NMR relaxation studies of fluorosubstituted tryptophans. JOURNAL OF BIOMOLECULAR NMR 2019; 73:401-409. [PMID: 31435857 PMCID: PMC6878660 DOI: 10.1007/s10858-019-00268-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 07/05/2019] [Indexed: 05/19/2023]
Abstract
We present 19F longitudinal and transverse relaxation studies for four differently fluorosubstituted L-tryptophans, which carry single F atoms in the indole ring, both in the context of the free amino acid and when located in the cyclophilin A protein. For the free 4F-, 5F-, 6F-, 7F-L-Trp, satisfactory agreement between experimentally measured and calculated relaxation rates was obtained, suggesting that the parameters used for calculating the rates for the indole frame are sufficiently accurate. We also measured and calculated relaxation rates for four differently 19F-tryptophan labeled cyclophilin A proteins, transferring the parameters from the free amino acid to the protein-bound moiety. Our results suggest that 19F relaxation data of the large and rigid indole ring in Trp are only moderately affected by protein motions and provide critical reference points for evaluating fluorine NMR relaxation in the future, especially in fluorotryptophan labeled proteins.
Collapse
Affiliation(s)
- Manman Lu
- Department of Structural Biology, University of Pittsburgh School of Medicine, 3501 Fifth Ave., Pittsburgh, PA, 15261, USA
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave., Pittsburgh, PA, 15261, USA
| | - Rieko Ishima
- Department of Structural Biology, University of Pittsburgh School of Medicine, 3501 Fifth Ave., Pittsburgh, PA, 15261, USA
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave., Pittsburgh, PA, 15261, USA
| | - Tatyana Polenova
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave., Pittsburgh, PA, 15261, USA
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716, USA
| | - Angela M Gronenborn
- Department of Structural Biology, University of Pittsburgh School of Medicine, 3501 Fifth Ave., Pittsburgh, PA, 15261, USA.
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave., Pittsburgh, PA, 15261, USA.
| |
Collapse
|
27
|
Takeuchi K, Baskaran K, Arthanari H. Structure determination using solution NMR: Is it worth the effort? JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2019; 306:195-201. [PMID: 31345771 DOI: 10.1016/j.jmr.2019.07.045] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 07/10/2019] [Accepted: 07/11/2019] [Indexed: 06/10/2023]
Abstract
It has been almost 40 years since solution NMR joined X-ray crystallography as a technique for determining high-resolution structures of proteins. Since then NMR derived structure has contributed in fundamental ways to our understanding of the function of biomolecules. With the already existing mature field of X-ray crystallography and the emergence of cryo-EM as techniques to tackle high-resolution structures of large protein complexes, the role of NMR in structure determination has been questioned. However, NMR has the unique ability to recapitulate the dynamic motion of proteins in their structures, while size limitations of the biomolecular systems that can be routinely studied still present challenges. The field has continually developed methodology and instrumentation since its introduction, pushing its frontiers and redefining its limits. Here we present a brief overview of NMR-based structure determination over the past 40 years. We outline the current state of the field and look ahead to the challenges that still need to be addressed to realize the future potential of NMR as a structural technique.
Collapse
Affiliation(s)
- Koh Takeuchi
- Molecular Profiling Research Center for Drug Discovery (Molprof), National Institute of Advanced Industrial Science and Technology (AIST), Tokyo 135-0064, Japan
| | - Kumaran Baskaran
- Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Dr, Madison, WI 53706, United States
| | - Haribabu Arthanari
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, United States; Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02115, United States.
| |
Collapse
|
28
|
Adhikary R, Zimmermann J, Stanfield RL, Wilson IA, Yu W, Oda M, Romesberg FE. Structure and Dynamics of Stacking Interactions in an Antibody Binding Site. Biochemistry 2019; 58:2987-2995. [PMID: 31243995 DOI: 10.1021/acs.biochem.9b00119] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
For years, antibodies (Abs) have been used as a paradigm for understanding how protein structure contributes to molecular recognition. However, with the ability to evolve Abs that recognize specific chromophores, they also have great potential as models for how protein dynamics contribute to molecular recognition. We previously raised murine Abs to different chromophores and, with the use of three-pulse photon echo peak shift spectroscopy, demonstrated that the immune system is capable of producing Abs with widely varying flexibility. We now report the characterization of the complexes formed between two Abs, 5D11 and 10A6, and the chromophoric ligand that they were evolved to recognize, 8-methoxypyrene-1,3,6-trisulfonic acid (MPTS). The sequences of the Ab genes indicate that they evolved from a common precursor. We also used a variety of spectroscopic methods to probe the photophysics and dynamics of the Ab-MPTS complexes and found that they are similar to each other but distinct from previously characterized anti-MPTS Abs. Structural studies revealed that this difference likely results from a unique mode of binding in which MPTS is sandwiched between the side chain of PheH98, which interacts with the chromophore via T-stacking, and the side chain of TrpL91, which interacts with the chromophore via parallel stacking. The T-stacking interaction appears to mediate relaxation on the picosecond time scale, while the parallel stacking appears to mediate relaxation on an ultrafast, femtosecond time scale, which dominates the response. The anti-MPTS Abs thus not only demonstrate the simultaneous use of the two limiting modes of stacking for molecular recognition, but also provide a unique opportunity to characterize how dynamics might contribute to molecular recognition. Both types of stacking are common in proteins and protein complexes where they may similarly contribute to dynamics and molecular recognition.
Collapse
Affiliation(s)
| | | | | | | | | | - Masayuki Oda
- Graduate School of Life and Environmental Sciences , Kyoto Prefectural University , 1-5, Hangi-cho , Shimogamo, Sakyo-ku, Kyoto 606-8522 , Japan
| | | |
Collapse
|
29
|
Gauto DF, Macek P, Barducci A, Fraga H, Hessel A, Terauchi T, Gajan D, Miyanoiri Y, Boisbouvier J, Lichtenecker R, Kainosho M, Schanda P. Aromatic Ring Dynamics, Thermal Activation, and Transient Conformations of a 468 kDa Enzyme by Specific 1H- 13C Labeling and Fast Magic-Angle Spinning NMR. J Am Chem Soc 2019; 141:11183-11195. [PMID: 31199882 DOI: 10.1021/jacs.9b04219] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Aromatic residues are located at structurally important sites of many proteins. Probing their interactions and dynamics can provide important functional insight but is challenging in large proteins. Here, we introduce approaches to characterize the dynamics of phenylalanine residues using 1H-detected fast magic-angle spinning (MAS) NMR combined with a tailored isotope-labeling scheme. Our approach yields isolated two-spin systems that are ideally suited for artifact-free dynamics measurements, and allows probing motions effectively without molecular weight limitations. The application to the TET2 enzyme assembly of ∼0.5 MDa size, the currently largest protein assigned by MAS NMR, provides insights into motions occurring on a wide range of time scales (picoseconds to milliseconds). We quantitatively probe ring-flip motions and show the temperature dependence by MAS NMR measurements down to 100 K. Interestingly, favorable line widths are observed down to 100 K, with potential implications for DNP NMR. Furthermore, we report the first 13C R1ρ MAS NMR relaxation-dispersion measurements and detect structural excursions occurring on a microsecond time scale in the entry pore to the catalytic chamber and at a trimer interface that was proposed as the exit pore. We show that the labeling scheme with deuteration at ca. 50 kHz MAS provides superior resolution compared to 100 kHz MAS experiments with protonated, uniformly 13C-labeled samples.
Collapse
Affiliation(s)
- Diego F Gauto
- Univ. Grenoble Alpes, CEA, CNRS , Institut de Biologie Structurale (IBS) , 71, avenue des martyrs , F-38044 Grenoble , France
| | - Pavel Macek
- Univ. Grenoble Alpes, CEA, CNRS , Institut de Biologie Structurale (IBS) , 71, avenue des martyrs , F-38044 Grenoble , France
| | - Alessandro Barducci
- Centre de Biochimie Structurale (CBS) , INSERM, CNRS, Université de Montpellier , Montpellier , France
| | - Hugo Fraga
- Univ. Grenoble Alpes, CEA, CNRS , Institut de Biologie Structurale (IBS) , 71, avenue des martyrs , F-38044 Grenoble , France.,Departamento de Biomedicina , Faculdade de Medicina da Universidade do Porto , Porto , Portugal.,i3S, Instituto de Investigação e Inovação em Saúde , Universidade do Porto , Porto , Portugal
| | - Audrey Hessel
- Univ. Grenoble Alpes, CEA, CNRS , Institut de Biologie Structurale (IBS) , 71, avenue des martyrs , F-38044 Grenoble , France
| | - Tsutomu Terauchi
- Graduate School of Science , Tokyo Metropolitan University , 1-1 Minami-ohsawa , Hachioji , Tokyo 192-0397 , Japan.,SI Innovation Center , Taiyo Nippon Sanso Corp. , 2008-2 Wada , Tama-city , Tokyo 206-0001 , Japan
| | - David Gajan
- Université de Lyon , Centre de RMN à Hauts Champs de Lyon CRMN, FRE 2034, Université de Lyon, CNRS, ENS Lyon, UCB Lyon 1 , 69100 Villeurbanne , France
| | - Yohei Miyanoiri
- Institute of Protein Research , Osaka University , 3-2 Yamadaoka , Suita , Osaka 565-0871 , Japan.,Structural Biology Research Center, Graduate School of Sciences , Nagoya University , Furo-cho, Chikusa-ku, Nagoya 464-8602 , Japan
| | - Jerome Boisbouvier
- Univ. Grenoble Alpes, CEA, CNRS , Institut de Biologie Structurale (IBS) , 71, avenue des martyrs , F-38044 Grenoble , France
| | - Roman Lichtenecker
- Institute of Organic Chemistry , University of Vienna , Währinger Str. 38 , 1090 Vienna , Austria
| | - Masatsune Kainosho
- Graduate School of Science , Tokyo Metropolitan University , 1-1 Minami-ohsawa , Hachioji , Tokyo 192-0397 , Japan.,Structural Biology Research Center, Graduate School of Sciences , Nagoya University , Furo-cho, Chikusa-ku, Nagoya 464-8602 , Japan
| | - Paul Schanda
- Univ. Grenoble Alpes, CEA, CNRS , Institut de Biologie Structurale (IBS) , 71, avenue des martyrs , F-38044 Grenoble , France
| |
Collapse
|
30
|
Abstract
Refining predicted protein structures with all-atom molecular dynamics simulations is one route to producing, entirely by computational means, structural models of proteins that rival in quality those that are determined by X-ray diffraction experiments. Slow rearrangements within the compact folded state, however, make routine refinement of predicted structures by unrestrained simulations infeasible. In this work, we draw inspiration from the fields of metallurgy and blacksmithing, where practitioners have worked out practical means of controlling equilibration by mechanically deforming their samples. We describe a two-step refinement procedure that involves identifying collective variables for mechanical deformations using a coarse-grained model and then sampling along these deformation modes in all-atom simulations. Identifying those low-frequency collective modes that change the contact map the most proves to be an effective strategy for choosing which deformations to use for sampling. The method is tested on 20 refinement targets from the CASP12 competition and is found to induce large structural rearrangements that drive the structures closer to the experimentally determined structures during relatively short all-atom simulations of 50 ns. By examining the accuracy of side-chain rotamer states in subensembles of structures that have varying degrees of similarity to the experimental structure, we identified the reorientation of aromatic side chains as a step that remains slow even when encouraging global mechanical deformations in the all-atom simulations. Reducing the side-chain rotamer isomerization barriers in the all-atom force field is found to further speed up refinement.
Collapse
|
31
|
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.
Collapse
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.
| |
Collapse
|
32
|
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.
Collapse
Affiliation(s)
- Ulrich Weininger
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, Halle, Germany.
| |
Collapse
|
33
|
Cousin SF, Kadeřávek P, Bolik-Coulon N, Gu Y, Charlier C, Carlier L, Bruschweiler-Li L, Marquardsen T, Tyburn JM, Brüschweiler R, Ferrage F. Time-Resolved Protein Side-Chain Motions Unraveled by High-Resolution Relaxometry and Molecular Dynamics Simulations. J Am Chem Soc 2018; 140:13456-13465. [DOI: 10.1021/jacs.8b09107] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Samuel F. Cousin
- Laboratoire des biomolécules, LBM, Département de chimie, École normale supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
| | - Pavel Kadeřávek
- Laboratoire des biomolécules, LBM, Département de chimie, École normale supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
| | - Nicolas Bolik-Coulon
- Laboratoire des biomolécules, LBM, Département de chimie, École normale supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
| | - Yina Gu
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Cyril Charlier
- Laboratoire des biomolécules, LBM, Département de chimie, École normale supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
| | - Ludovic Carlier
- Laboratoire des biomolécules, LBM, Département de chimie, École normale supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
| | - Lei Bruschweiler-Li
- Campus Chemical Instrument Center, The Ohio State University, Columbus, Ohio 43210, United States
| | | | - Jean-Max Tyburn
- Bruker BioSpin, 34 rue de l’Industrie BP 10002, 67166 Wissembourg Cedex, France
| | - Rafael Brüschweiler
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
- Campus Chemical Instrument Center, The Ohio State University, Columbus, Ohio 43210, United States
- Department of Biological Chemistry and Pharmacology, The Ohio State University, Columbus, Ohio 43210, United States
| | - Fabien Ferrage
- Laboratoire des biomolécules, LBM, Département de chimie, École normale supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
| |
Collapse
|
34
|
Dimova M, Devedjiev YD. Protein crystal lattices are dynamic assemblies: the role of conformational entropy in the protein condensed phase. IUCRJ 2018; 5:130-140. [PMID: 29765602 PMCID: PMC5947717 DOI: 10.1107/s2052252517017833] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 12/13/2017] [Indexed: 05/03/2023]
Abstract
Until recently, the occurrence of conformational entropy in protein crystal contacts was considered to be a very unlikely event. A study based on the most accurately refined protein structures demonstrated that side-chain conformational entropy and static disorder might be common in protein crystal lattices. The present investigation uses structures refined using ensemble refinement to show that although paradoxical, conformational entropy is likely to be the major factor in the emergence and integrity of the protein condensed phase. This study reveals that the role of shape entropy and local entropic forces expands beyond the onset of crystallization. For the first time, the complete pattern of intermolecular interactions by protein atoms in crystal lattices is presented, which shows that van der Waals interactions dominate in crystal formation.
Collapse
Affiliation(s)
- Margarita Dimova
- Department of Anesthesiology, University of Virginia, 1215 Lee Street, Charlottesville, VA 22908, USA
| | - Yancho D. Devedjiev
- Department of Anesthesiology, University of Virginia, 1215 Lee Street, Charlottesville, VA 22908, USA
| |
Collapse
|
35
|
Abstract
The measurement of R1ρ , the longitudinal relaxation rate constant in the rotating frame, is one of the few available methods to characterize the μs-ms functional dynamics of biomolecules. Here, we focus on 15N R1ρ experiments for protein NH groups. We present protocols for both on- and off-resonance 15N R1ρ measurements needed for relaxation dispersion studies, and describe the data analysis for extracting kinetic and thermodynamic parameters characterizing the motional processes.
Collapse
Affiliation(s)
- Francesca Massi
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, 01605, USA.
| | - Jeffrey W Peng
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA
| |
Collapse
|
36
|
Vugmeyster L, Ostrovsky D, Hoatson GL, Qiang W, Falconer IB. Solvent-Driven Dynamical Crossover in the Phenylalanine Side-Chain from the Hydrophobic Core of Amyloid Fibrils Detected by 2H NMR Relaxation. J Phys Chem B 2017; 121:7267-7275. [PMID: 28699757 PMCID: PMC5567839 DOI: 10.1021/acs.jpcb.7b04726] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Aromatic residues are important markers of dynamical changes in proteins' hydrophobic cores. In this work we investigated the dynamics of the F19 side-chain in the core of amyloid fibrils across a wide temperature range of 300 to 140 K. We utilized solid-state 2H NMR relaxation to demonstrate the presence of a solvent-driven dynamical crossover between different motional regimes, often also referred to as the dynamical transition. In particular, the dynamics are dominated by small-angle fluctuations at low temperatures and by π-flips of the aromatic ring at high temperatures. The crossover temperature is more than 43 degrees lower for the hydrated state of the fibrils compared to the dry state, indicating that interactions with water facilitate π-flips. Further, crossover temperatures are shown to be very sensitive to polymorphic states of the fibrils, such as the 2-fold and 3-fold symmetric morphologies of the wild-type protein as well as D23N mutant protofibrils. We speculate that these differences can be attributed, at least partially, to enhanced interactions with water in the 3-fold polymorph, which has been shown to have a water-accessible cavity. Combined with previous studies of methyl group dynamics, the results highlight the presence of multiple dynamics modes in the core of the fibrils, which was originally believed to be quite rigid.
Collapse
Affiliation(s)
- Liliya Vugmeyster
- Department of Chemistry, University of Colorado at Denver, Denver, CO 80204
| | - Dmitry Ostrovsky
- Department of Mathematics, University of Colorado at Denver, Denver, CO 80204
| | - Gina L. Hoatson
- Department of Physics, College of William and Mary, Williamsburg, Virginia, 23187
| | - Wei Qiang
- Department of Chemistry, Binghamton University, Binghamton, NY 13902
| | - Isaac B. Falconer
- Department of Chemistry, University of Colorado at Denver, Denver, CO 80204
| |
Collapse
|
37
|
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.
Collapse
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.
| |
Collapse
|
38
|
Kamenik AS, Kahler U, Fuchs JE, Liedl KR. Localization of Millisecond Dynamics: Dihedral Entropy from Accelerated MD. J Chem Theory Comput 2016; 12:3449-55. [PMID: 27322931 PMCID: PMC4980685 DOI: 10.1021/acs.jctc.6b00231] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Indexed: 11/28/2022]
Abstract
Here, we demonstrate a method to capture local dynamics on a time scale 3 orders of magnitude beyond state-of-the-art simulation approaches. We apply accelerated molecular dynamics simulations for conformational sampling and extract reweighted backbone dihedral distributions. Local dynamics are characterized by torsional probabilities, resulting in residue-wise dihedral entropies. Our approach is successfully validated for three different protein systems of increasing size: alanine dipeptide, bovine pancreatic trypsin inhibitor (BPTI), and the major birch pollen allergen Bet v 1a. We demonstrate excellent agreement of flexibility profiles with both large-scale computer simulations and NMR experiments. Thus, our method provides efficient access to local protein dynamics on extended time scales of high biological relevance.
Collapse
Affiliation(s)
- Anna S. Kamenik
- Institute of General, Inorganic
and Theoretical Chemistry, Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innsbruck, Austria
| | - Ursula Kahler
- Institute of General, Inorganic
and Theoretical Chemistry, Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innsbruck, Austria
| | - Julian E. Fuchs
- Institute of General, Inorganic
and Theoretical Chemistry, Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innsbruck, Austria
| | - Klaus R. Liedl
- Institute of General, Inorganic
and Theoretical Chemistry, Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innsbruck, Austria
| |
Collapse
|
39
|
Vallurupalli P, Chakrabarti N, Pomès R, Kay LE. Atomistic picture of conformational exchange in a T4 lysozyme cavity mutant: an experiment-guided molecular dynamics study. Chem Sci 2016; 7:3602-3613. [PMID: 30008994 PMCID: PMC6008728 DOI: 10.1039/c5sc03886c] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 01/03/2016] [Indexed: 12/16/2022] Open
Abstract
Despite the importance of dynamics to protein function there is little information about the states that are formed as the protein explores its conformational landscape or about the mechanism by which transitions between the different states occur. Here we used a combined NMR spin relaxation and unbiased molecular dynamics (MD) approach to investigate the exchange process by which a cavity in an L99A mutant of T4 lysozyme (T4L 99A) interconverts between an empty and occupied form that involves repositioning of an aromatic residue, Phe114. Although structures of the end-states of the exchange process are available, insight into the mechanism by which the transition takes place cannot be obtained from experiment and the timescales involved are too slow to address using brute force MD. Using spin relaxation NMR methods, we have identified a triple-mutant of T4L that undergoes the same exchange process as T4L L99A but where the minor state lifetime has decreased significantly so that the spontaneous conformational transition to the major state can be studied using all-atom MD simulations. The simulation trajectories were analyzed using Markov state models and the energy landscape so obtained is in good agreement with expectations based on NMR studies. Notably there is no large-scale perturbation of the structure during the transition, multiple intermediates are formed between the two similar exchanging conformations and the free energy barrier between these two well-folded, compact forms is small (6kBT), only slightly larger than for processes considered to be barrierless.
Collapse
Affiliation(s)
- Pramodh Vallurupalli
- TIFR Centre for Interdisciplinary Sciences , 21 Brundavan Colony, Narsingi , Hyderabad 500075 , India .
| | - Nilmadhab Chakrabarti
- Molecular Structure and Function , Hospital for Sick Children , Toronto , ON , Canada M5G 1X8
| | - Régis Pomès
- Molecular Structure and Function , Hospital for Sick Children , Toronto , ON , Canada M5G 1X8
- Department of Biochemistry , University of Toronto , Toronto , ON , Canada M5S 1A8
| | - Lewis E Kay
- Molecular Structure and Function , Hospital for Sick Children , Toronto , ON , Canada M5G 1X8
- Department of Biochemistry , University of Toronto , Toronto , ON , Canada M5S 1A8
- Departments of Molecular Genetics and Chemistry , University of Toronto , Toronto , ON M5S 1A8 , Canada .
| |
Collapse
|
40
|
Vugmeyster L, Ostrovsky D, Villafranca T, Sharp J, Xu W, Lipton AS, Hoatson GL, Vold RL. Dynamics of Hydrophobic Core Phenylalanine Residues Probed by Solid-State Deuteron NMR. J Phys Chem B 2015; 119:14892-904. [PMID: 26529128 PMCID: PMC4970646 DOI: 10.1021/acs.jpcb.5b09299] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We conducted a detailed investigation of the dynamics of two phenylalanine side chains in the hydrophobic core of the villin headpiece subdomain protein (HP36) in the hydrated powder state over the 298-80 K temperature range. Our main tools were static deuteron NMR measurements of longitudinal relaxation and line shapes supplemented with computational modeling. The temperature dependence of the relaxation times reveals the presence of two main mechanisms that can be attributed to the ring-flips, dominating at high temperatures, and small-angle fluctuations, dominating at low temperatures. The relaxation is nonexponential at all temperatures with the extent of nonexponentiality increasing from higher to lower temperatures. This behavior suggests a distribution of conformers with unique values of activation energies. The central values of the activation energies for the ring-flipping motions are among the smallest reported for aromatic residues in peptides and proteins and point to a very mobile hydrophobic core. The analysis of the widths of the distributions, in combination with the earlier results on the dynamics of flanking methyl groups (Vugmeyster et al. J. Phys. Chem. B 2013, 117, 6129-6137), suggests that the hydrophobic core undergoes slow concerted fluctuations. There is a pronounced effect of dehydration on the ring-flipping motions, which shifts the distribution toward more rigid conformers. The crossover temperature between the regions of dominance of the small-angle fluctuations and ring-flips shifts from 195 K in the hydrated protein to 278 K in the dry one. This result points to the role of solvent in softening the core and highlights aromatic residues as markers of the protein dynamical transitions.
Collapse
Affiliation(s)
| | | | | | - Janelle Sharp
- University of Alaska Anchorage, Anchorage, Alaska, 99508
| | - Wei Xu
- College of William and Mary, Williamsburg, Virginia, 23187
| | - Andrew S. Lipton
- Pacific Northwest National Laboratory, Richland, Washington, 99354
| | | | - Robert L. Vold
- College of William and Mary, Williamsburg, Virginia, 23187
| |
Collapse
|
41
|
Abstract
Protein cavities or voids are observed as defects in atomic packing. Cavities have long been suggested to play important roles in protein dynamics and function, but the underlying origin and mechanism remains elusive. Here, recent studies about the cavities characterized by high-pressure NMR spectroscopy have been reviewed. Analysis of the pressure-dependent chemical shifts showed both linear and nonlinear response of proteins to pressure. The linear response corresponded to compression within the native ensemble, while the nonlinear response indicated the involvement of low-lying excited states that were different from the native state. The finding of non-linear pressure shifts in various proteins suggested that the existence of the low-lying excited states was common for globular proteins. However, the absolute nonlinear coefficient values varied significantly from protein to protein, and showed a good correlation with the density of cavities. Extensive studies on hen lysozyme as a model system showed that the cavity hydration and water penetration into the interior of proteins was an origin of the conformational transition to the excited states. The importance of cavities for protein function and evolution has also been explained. In addition to these "equilibrium" cavities, there are also "transient" cavities formed in the interior of the protein structure, as manifested by the ring flip motions of aromatic rings. The significance of transient cavities, reflecting an intrinsic dynamic nature within the native state, has also been discussed.
Collapse
|
42
|
Fuchs JE, Waldner BJ, Huber RG, von Grafenstein S, Kramer C, Liedl KR. Independent Metrics for Protein Backbone and Side-Chain Flexibility: Time Scales and Effects of Ligand Binding. J Chem Theory Comput 2015; 11:851-60. [DOI: 10.1021/ct500633u] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Julian E. Fuchs
- Institute
of General, Inorganic and Theoretical Chemistry, and Center for Molecular
Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain
80-82, A-6020 Innsbruck, Tyrol, Austria
- Centre
for Molecular Informatics, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Birgit J. Waldner
- Institute
of General, Inorganic and Theoretical Chemistry, and Center for Molecular
Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain
80-82, A-6020 Innsbruck, Tyrol, Austria
| | - Roland G. Huber
- Institute
of General, Inorganic and Theoretical Chemistry, and Center for Molecular
Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain
80-82, A-6020 Innsbruck, Tyrol, Austria
- Bioinformatics
Institute, Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, Matrix #07-01, 138671 Singapore
| | - Susanne von Grafenstein
- Institute
of General, Inorganic and Theoretical Chemistry, and Center for Molecular
Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain
80-82, A-6020 Innsbruck, Tyrol, Austria
| | - Christian Kramer
- Institute
of General, Inorganic and Theoretical Chemistry, and Center for Molecular
Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain
80-82, A-6020 Innsbruck, Tyrol, Austria
| | - Klaus R. Liedl
- Institute
of General, Inorganic and Theoretical Chemistry, and Center for Molecular
Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain
80-82, A-6020 Innsbruck, Tyrol, Austria
| |
Collapse
|
43
|
Torchia DA. NMR studies of dynamic biomolecular conformational ensembles. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2015; 84-85:14-32. [PMID: 25669739 PMCID: PMC4325279 DOI: 10.1016/j.pnmrs.2014.11.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 11/19/2014] [Accepted: 11/19/2014] [Indexed: 05/06/2023]
Abstract
Multidimensional heteronuclear NMR approaches can provide nearly complete sequential signal assignments of isotopically enriched biomolecules. The availability of assignments together with measurements of spin relaxation rates, residual spin interactions, J-couplings and chemical shifts provides information at atomic resolution about internal dynamics on timescales ranging from ps to ms, both in solution and in the solid state. However, due to the complexity of biomolecules, it is not possible to extract a unique atomic-resolution description of biomolecular motions even from extensive NMR data when many conformations are sampled on multiple timescales. For this reason, powerful computational approaches are increasingly applied to large NMR data sets to elucidate conformational ensembles sampled by biomolecules. In the past decade, considerable attention has been directed at an important class of biomolecules that function by binding to a wide variety of target molecules. Questions of current interest are: "Does the free biomolecule sample a conformational ensemble that encompasses the conformations found when it binds to various targets; and if so, on what time scale is the ensemble sampled?" This article reviews recent efforts to answer these questions, with a focus on comparing ensembles obtained for the same biomolecules by different investigators. A detailed comparison of results obtained is provided for three biomolecules: ubiquitin, calmodulin and the HIV-1 trans-activation response RNA.
Collapse
Affiliation(s)
- Dennis A Torchia
- National Institutes of Health (NIH), 5 Memorial Drive, Bethesda, MD 20892, USA.
| |
Collapse
|
44
|
Weininger U, Modig K, Akke M. Ring Flips Revisited: 13C Relaxation Dispersion Measurements of Aromatic Side Chain Dynamics and Activation Barriers in Basic Pancreatic Trypsin Inhibitor. Biochemistry 2014; 53:4519-25. [DOI: 10.1021/bi500462k] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [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
| | - Kristofer Modig
- Department of Biophysical
Chemistry, Center for Molecular Protein Science, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
| | - Mikael Akke
- Department of Biophysical
Chemistry, Center for Molecular Protein Science, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
| |
Collapse
|
45
|
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.
Collapse
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
| |
Collapse
|
46
|
|
47
|
Bocharov EV, Lesovoy DM, Goncharuk SA, Goncharuk MV, Hristova K, Arseniev AS. Structure of FGFR3 transmembrane domain dimer: implications for signaling and human pathologies. Structure 2013; 21:2087-93. [PMID: 24120763 PMCID: PMC3844157 DOI: 10.1016/j.str.2013.08.026] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2013] [Revised: 08/28/2013] [Accepted: 08/30/2013] [Indexed: 11/22/2022]
Abstract
Fibroblast growth factor receptor 3 (FGFR3) transduces biochemical signals via lateral dimerization in the plasma membrane, and plays an important role in human development and disease. Eight different pathogenic mutations, implicated in cancers and growth disorders, have been identified in the FGFR3 transmembrane segment. Here, we describe the dimerization of the FGFR3 transmembrane domain in membrane-mimicking DPC/SDS (9/1) micelles. In the solved NMR structure, the two transmembrane helices pack into a symmetric left-handed dimer, with intermolecular stacking interactions occurring in the dimer central region. Some pathogenic mutations fall within the helix-helix interface, whereas others are located within a putative alternative interface. This implies that although the observed dimer structure is important for FGFR3 signaling, the mechanism of FGFR3-mediated transduction across the membrane is complex. We propose an FGFR3 signaling mechanism that is based on the solved structure, available structures of isolated soluble FGFR domains, and published biochemical and biophysical data.
Collapse
Affiliation(s)
- Eduard V Bocharov
- Department of Structural Biology, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya Street 16/10, Moscow 117997, Russian Federation.
| | | | | | | | | | | |
Collapse
|
48
|
Audin MJC, Dorn G, Fromm SA, Reiss K, Schütz S, Vorländer MK, Sprangers R. The Archaeal Exosome: Identification and Quantification of Site-Specific Motions That Correlate with Cap and RNA Binding. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201302811] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
49
|
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
| |
Collapse
|
50
|
Audin MJC, Dorn G, Fromm SA, Reiss K, Schütz S, Vorländer MK, Sprangers R. The archaeal exosome: identification and quantification of site-specific motions that correlate with cap and RNA binding. Angew Chem Int Ed Engl 2013; 52:8312-6. [PMID: 23804404 PMCID: PMC3840697 DOI: 10.1002/anie.201302811] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Indexed: 11/16/2022]
Affiliation(s)
- Maxime J C Audin
- Max Planck Institute for Developmental Biology, Spemannstrasse 35, 72076 Tübingen, Germany
| | | | | | | | | | | | | |
Collapse
|