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Tagami K, Thicklin R, Jain S, Equbal A, Li M, Zens T, Siaw A, Han S. Design of a cryogen-free high field dual EPR and DNP probe. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2023; 347:107351. [PMID: 36599253 DOI: 10.1016/j.jmr.2022.107351] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 11/29/2022] [Accepted: 11/30/2022] [Indexed: 06/17/2023]
Abstract
We present the design and construction of a cryogen free, dual electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) probe for novel dynamic nuclear polarization (DNP) experiments and concurrent "in situ" analysis of DNP mechanisms. We focus on the probe design that meets the balance between EPR, NMR, and low temperature performance, while maintaining a high degree of versatility: allowing multi-nuclear NMR detection as well as broadband DNP/EPR excitation/detection. To accomplish high NMR/EPR performance, we implement a novel inductively coupled double resonance NMR circuit (1H-13C) in a solid state probe operating at cryogenic temperatures. The components of the circuit were custom built to provide maximum NMR performance, and the physical layout of this circuit was numerically optimized via magnetic field simulations to allow maximum microwave transmission to the sample for optimal EPR performance. Furthermore this probe is based around a cryogen free gas exchange cryostat and has been designed to allow unlimited experiment times down to 8.5 Kelvin with minimal cost. The affordability of EPR/DNP experiment is an extremely important aspect for broader impact with magnetic resonance measurements. The purpose of this article is to provide as complete information as we have available for others with interest in building a dual DNP/EPR instrument based around a cryogen-free cryostat.
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Affiliation(s)
- Kan Tagami
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, United States
| | - Raymond Thicklin
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, United States
| | - Sheetal Jain
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, United States
| | - Asif Equbal
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, United States
| | - Miranda Li
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, United States
| | - Toby Zens
- JEOL USA, Inc., 11 Dearborn Road, Peabody, MA 01960, United States
| | - Anthony Siaw
- JEOL USA, Inc., 11 Dearborn Road, Peabody, MA 01960, United States
| | - Songi Han
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, United States; Department of Chemical Engineering, University of California, Santa Barbara, Santa Barbara, CA 93106, United States.
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2
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Eddy MT, Yu TY, Wagner G, Griffin RG. Structural characterization of the human membrane protein VDAC2 in lipid bilayers by MAS NMR. JOURNAL OF BIOMOLECULAR NMR 2019; 73:451-460. [PMID: 31407201 PMCID: PMC6819253 DOI: 10.1007/s10858-019-00242-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Accepted: 03/19/2019] [Indexed: 05/25/2023]
Abstract
The second isoform of the human voltage dependent anion channel (VDAC2) is a mitochondrial porin that translocates calcium and other metabolites across the outer mitochondrial membrane. VDAC2 has been implicated in cardioprotection and plays a critical role in a unique apoptotic pathway in tumor cells. Despite its medical importance, there have been few biophysical studies of VDAC2 in large part due to the difficulty of obtaining homogeneous preparations of the protein for spectroscopic characterization. Here we present high resolution magic angle spinning nuclear magnetic resonance (NMR) data obtained from homogeneous preparation of human VDAC2 in 2D crystalline lipid bilayers. The excellent resolution in the spectra permit several sequence-specific assignments of the signals for a large portion of the VDAC2 N-terminus and several other residues in two- and three-dimensional heteronuclear correlation experiments. The first 12 residues appear to be dynamic, are not visible in cross polarization experiments, and they are not sufficiently mobile on very fast timescales to be visible in 13C INEPT experiments. A comparison of the NMR spectra of VDAC2 and VDAC1 obtained from highly similar preparations demonstrates that the spectral quality, line shapes and peak dispersion exhibited by the two proteins are nearly identical. This suggests an overall similar dynamic behavior and conformational homogeneity, which is in contrast to two earlier reports that suggested an inherent conformational heterogeneity of VDAC2 in membranes. The current data suggest that the sample preparation and spectroscopic methods are likely applicable to studying other human membrane porins, including human VDAC3, which has not yet been structurally characterized.
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Affiliation(s)
- Matthew T Eddy
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Departments of Chemistry, University of Florida, Gainesville, FL, 32611, USA
| | - Tsyr-Yan Yu
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, 02115, USA
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, 10617, Taiwan, Republic of China
| | - Gerhard Wagner
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, 02115, USA
| | - Robert G Griffin
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
- Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
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3
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Formation of the β-barrel assembly machinery complex in lipid bilayers as seen by solid-state NMR. Nat Commun 2018; 9:4135. [PMID: 30297837 PMCID: PMC6175958 DOI: 10.1038/s41467-018-06466-w] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 09/04/2018] [Indexed: 11/27/2022] Open
Abstract
The β-barrel assembly machinery (BAM) is a pentameric complex (BamA–E), which catalyzes the essential process of β-barrel protein insertion into the outer membrane of E. coli. Thus far, a detailed understanding of the insertion mechanism has been elusive but recent results suggest that local protein motion, in addition to the surrounding membrane environment, may be of critical relevance. We have devised a high-sensitivity solid-state NMR approach to directly probe protein motion and the structural changes associated with BAM complex assembly in lipid bilayers. Our results reveal how essential BamA domains, such as the interface formed by the polypeptide transport associated domains P4 and P5 become stabilized after complex formation and suggest that BamA β-barrel opening and P5 reorientation is directly related to complex formation in membranes. Both the lateral gate, as well as P5, exhibit local dynamics, a property that could play an integral role in substrate recognition and insertion. The β-barrel assembly machinery (BAM) catalyzes β-barrel protein insertion into the outer membrane of E.coli. Here authors employ high-sensitivity solid-state NMR to reveal how the lipid environment and formation of the BamA-BamCDE complex affect BamA structure and dynamics with regards to the lateral gate and the β-barrel associated domains.
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4
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Naito A, Matsumori N, Ramamoorthy A. Dynamic membrane interactions of antibacterial and antifungal biomolecules, and amyloid peptides, revealed by solid-state NMR spectroscopy. Biochim Biophys Acta Gen Subj 2018; 1862:307-323. [PMID: 28599848 PMCID: PMC6384124 DOI: 10.1016/j.bbagen.2017.06.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Revised: 05/28/2017] [Accepted: 06/02/2017] [Indexed: 12/12/2022]
Abstract
A variety of biomolecules acting on the cell membrane folds into a biologically active structure in the membrane environment. It is, therefore, important to determine the structures and dynamics of such biomolecules in a membrane environment. While several biophysical techniques are used to obtain low-resolution information, solid-state NMR spectroscopy is one of the most powerful means for determining the structure and dynamics of membrane bound biomolecules such as antibacterial biomolecules and amyloidogenic proteins; unlike X-ray crystallography and solution NMR spectroscopy, applications of solid-state NMR spectroscopy are not limited by non-crystalline, non-soluble nature or molecular size of membrane-associated biomolecules. This review article focuses on the applications of solid-state NMR techniques to study a few selected antibacterial and amyloid peptides. Solid-state NMR studies revealing the membrane inserted bent α-helical structure associated with the hemolytic activity of bee venom melittin and the chemical shift oscillation analysis used to determine the transmembrane structure (with α-helix and 310-helix in the N- and C-termini, respectively) of antibiotic peptide alamethicin are discussed in detail. Oligomerization of an amyloidogenic islet amyloid polypeptide (IAPP, or also known as amylin) resulting from its aggregation in a membrane environment, molecular interactions of the antifungal natural product amphotericin B with ergosterol in lipid bilayers, and the mechanism of lipid raft formation by sphingomyelin studied using solid state NMR methods are also discussed in this review article. This article is part of a Special Issue entitled "Biophysical Exploration of Dynamical Ordering of Biomolecular Systems" edited by Dr. Koichi Kato.
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Affiliation(s)
- Akira Naito
- Graduate School of Engineering, Yokohama National University, Yokohama 240-8501, Japan.
| | - Nobuaki Matsumori
- Department of Chemistry, Graduate School of Science, Kyushu University, Fukuoka 819-0395, Japan
| | - Ayyalusamy Ramamoorthy
- Biophysics Program, University of Michigan, Ann Arbor, MI 48109-1055, USA; Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA
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5
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Baker LA, Sinnige T, Schellenberger P, de Keyzer J, Siebert CA, Driessen AJM, Baldus M, Grünewald K. Combined 1H-Detected Solid-State NMR Spectroscopy and Electron Cryotomography to Study Membrane Proteins across Resolutions in Native Environments. Structure 2017; 26:161-170.e3. [PMID: 29249608 PMCID: PMC5758107 DOI: 10.1016/j.str.2017.11.011] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 10/02/2017] [Accepted: 11/15/2017] [Indexed: 11/15/2022]
Abstract
Membrane proteins remain challenging targets for structural biology, despite much effort, as their native environment is heterogeneous and complex. Most methods rely on detergents to extract membrane proteins from their native environment, but this removal can significantly alter the structure and function of these proteins. Here, we overcome these challenges with a hybrid method to study membrane proteins in their native membranes, combining high-resolution solid-state nuclear magnetic resonance spectroscopy and electron cryotomography using the same sample. Our method allows the structure and function of membrane proteins to be studied in their native environments, across different spatial and temporal resolutions, and the combination is more powerful than each technique individually. We use the method to demonstrate that the bacterial membrane protein YidC adopts a different conformation in native membranes and that substrate binding to YidC in these native membranes differs from purified and reconstituted systems. CryoET and ssNMR give complementary information about proteins in native membranes One sample can be prepared for both methods without the use of detergents Hybrid method shows differences between purified and native preparations of YidC Sample preparation reduces costs and time and suggests new strategy for assignment
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Affiliation(s)
- Lindsay A Baker
- NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, 3584 CH Utrecht, the Netherlands; Oxford Particle Imaging Centre, Division of Structural Biology, University of Oxford, The Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK.
| | - Tessa Sinnige
- NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, 3584 CH Utrecht, the Netherlands
| | - Pascale Schellenberger
- Oxford Particle Imaging Centre, Division of Structural Biology, University of Oxford, The Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Jeanine de Keyzer
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG Groningen, the Netherlands; The Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 11, 9747 AG Groningen, the Netherlands
| | - C Alistair Siebert
- Oxford Particle Imaging Centre, Division of Structural Biology, University of Oxford, The Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Arnold J M Driessen
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG Groningen, the Netherlands; The Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 11, 9747 AG Groningen, the Netherlands
| | - Marc Baldus
- NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, 3584 CH Utrecht, the Netherlands.
| | - Kay Grünewald
- Oxford Particle Imaging Centre, Division of Structural Biology, University of Oxford, The Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK.
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6
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Rogawski R, Sergeyev IV, Zhang Y, Tran TH, Li Y, Tong L, McDermott AE. NMR Signal Quenching from Bound Biradical Affinity Reagents in DNP Samples. J Phys Chem B 2017; 121:10770-10781. [PMID: 29116793 PMCID: PMC5842680 DOI: 10.1021/acs.jpcb.7b08274] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
We characterize the effect of specifically bound biradicals on the NMR spectra of dihydrofolate reductase from E. coli. Dynamic nuclear polarization methods enhance the signal-to-noise of solid state NMR experiments by transferring polarization from unpaired electrons of biradicals to nuclei. There has been recent interest in colocalizing the paramagnetic polarizing agents with the analyte of interest through covalent or noncovalent specific interactions. This experimental approach broadens the scope of dynamic nuclear polarization methods by offering the possibility of selective signal enhancements and the potential to work in a broad range of environments. Paramagnetic compounds can have other effects on the NMR spectroscopy of nearby nuclei, including broadening of nuclear resonances due to the proximity of the paramagnetic agent. Understanding the distance dependence of these interactions is important for the success of the technique. Here we explore paramagnetic signal quenching due to a bound biradical, specifically a biradical-derivatized trimethoprim ligand of E. coli dihydrofolate reductase. Biradical-derivatized trimethoprim has nanomolar affinity for its target, and affords strong and selective signal enhancements in dynamic nuclear polarization experiments. In this work, we show that, although the trimethoprim fragment is well ordered, the biradical (TOTAPOL) moiety is disordered when bound to the protein. The distance dependence in bleaching of NMR signal intensity allows us to detect numerous NMR signals in the protein. We present the possibility that static disorder and electron spin diffusion play roles in this observation, among other contributions. The fact that the majority of signals are observed strengthens the case for the use of high affinity or covalent radicals in dynamic nuclear polarization solid state NMR enhancement.
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Affiliation(s)
- Rivkah Rogawski
- Department of Chemistry, Columbia University , New York, New York 10027, United States
| | - Ivan V Sergeyev
- Department of Chemistry, Columbia University , New York, New York 10027, United States
| | - Yinglu Zhang
- Department of Biological Sciences, Columbia University , New York, New York 10027, United States
| | - Timothy H Tran
- Department of Biological Sciences, Columbia University , New York, New York 10027, United States
| | - Yongjun Li
- Department of Chemistry, Columbia University , New York, New York 10027, United States
| | - Liang Tong
- Department of Biological Sciences, Columbia University , New York, New York 10027, United States
| | - Ann E McDermott
- Department of Chemistry, Columbia University , New York, New York 10027, United States
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7
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Rogawski R, McDermott AE. New NMR tools for protein structure and function: Spin tags for dynamic nuclear polarization solid state NMR. Arch Biochem Biophys 2017; 628:102-113. [PMID: 28623034 PMCID: PMC5815514 DOI: 10.1016/j.abb.2017.06.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 06/05/2017] [Accepted: 06/12/2017] [Indexed: 12/13/2022]
Abstract
Magic angle spinning solid state NMR studies of biological macromolecules [1-3] have enabled exciting studies of membrane proteins [4,5], amyloid fibrils [6], viruses, and large macromolecular assemblies [7]. Dynamic nuclear polarization (DNP) provides a means to enhance detection sensitivity for NMR, particularly for solid state NMR, with many recent biological applications and considerable contemporary efforts towards elaboration and optimization of the DNP experiment. This review explores precedents and innovations in biological DNP experiments, especially highlighting novel chemical biology approaches to introduce the radicals that serve as a source of polarization in DNP experiments.
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Affiliation(s)
- Rivkah Rogawski
- Department of Chemistry, Columbia University, NY, NY 10027, United States
| | - Ann E McDermott
- Department of Chemistry, Columbia University, NY, NY 10027, United States.
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8
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Applications of solid-state NMR to membrane proteins. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2017; 1865:1577-1586. [PMID: 28709996 DOI: 10.1016/j.bbapap.2017.07.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 06/30/2017] [Accepted: 07/07/2017] [Indexed: 11/23/2022]
Abstract
Membrane proteins mediate flow of molecules, signals, and energy between cells and intracellular compartments. Understanding membrane protein function requires a detailed understanding of the structural and dynamic properties involved. Lipid bilayers provide a native-like environment for structure-function investigations of membrane proteins. In this review we give a general discourse on the recent progress in the field of solid-state NMR of membrane proteins. Solid-state NMR is a variation of NMR spectroscopy that is applicable to molecular systems with restricted mobility, such as high molecular weight proteins and protein complexes, supramolecular assemblies, or membrane proteins in a phospholipid environment. We highlight recent advances in applications of solid-state NMR to membrane proteins, specifically focusing on the recent developments in the field of Dynamic Nuclear Polarization, proton detection, and solid-state NMR applications in situ (in cell membranes). This article is part of a Special Issue entitled: Biophysics in Canada, edited by Lewis Kay, John Baenziger, Albert Berghuis and Peter Tieleman.
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9
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Tian Y, Schwieters CD, Opella SJ, Marassi FM. High quality NMR structures: a new force field with implicit water and membrane solvation for Xplor-NIH. JOURNAL OF BIOMOLECULAR NMR 2017; 67:35-49. [PMID: 28035651 PMCID: PMC5487259 DOI: 10.1007/s10858-016-0082-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 12/11/2016] [Indexed: 06/06/2023]
Abstract
Structure determination of proteins by NMR is unique in its ability to measure restraints, very accurately, in environments and under conditions that closely mimic those encountered in vivo. For example, advances in solid-state NMR methods enable structure determination of membrane proteins in detergent-free lipid bilayers, and of large soluble proteins prepared by sedimentation, while parallel advances in solution NMR methods and optimization of detergent-free lipid nanodiscs are rapidly pushing the envelope of the size limit for both soluble and membrane proteins. These experimental advantages, however, are partially squandered during structure calculation, because the commonly used force fields are purely repulsive and neglect solvation, Van der Waals forces and electrostatic energy. Here we describe a new force field, and updated energy functions, for protein structure calculations with EEFx implicit solvation, electrostatics, and Van der Waals Lennard-Jones forces, in the widely used program Xplor-NIH. The new force field is based primarily on CHARMM22, facilitating calculations with a wider range of biomolecules. The new EEFx energy function has been rewritten to enable OpenMP parallelism, and optimized to enhance computation efficiency. It implements solvation, electrostatics, and Van der Waals energy terms together, thus ensuring more consistent and efficient computation of the complete nonbonded energy lists. Updates in the related python module allow detailed analysis of the interaction energies and associated parameters. The new force field and energy function work with both soluble proteins and membrane proteins, including those with cofactors or engineered tags, and are very effective in situations where there are sparse experimental restraints. Results obtained for NMR-restrained calculations with a set of five soluble proteins and five membrane proteins show that structures calculated with EEFx have significant improvements in accuracy, precision, and conformation, and that structure refinement can be obtained by short relaxation with EEFx to obtain improvements in these key metrics. These developments broaden the range of biomolecular structures that can be calculated with high fidelity from NMR restraints.
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Affiliation(s)
- Ye Tian
- Sanford-Burnham-Prebys Medical Discovery Institute, 10901 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Charles D Schwieters
- Center for Information Technology, National Institutes of Health, Building 12A, Bethesda, MD, 20892-5624, USA
| | - Stanley J Opella
- Department of Chemistry and Biochemistry, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0307, USA
| | - Francesca M Marassi
- Sanford-Burnham-Prebys Medical Discovery Institute, 10901 North Torrey Pines Road, La Jolla, CA, 92037, USA.
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Affiliation(s)
- Benjamin J. Wylie
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, USA
| | - Hoa Q. Do
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, USA
| | - Collin G. Borcik
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, USA
| | - Emily P. Hardy
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX, USA
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11
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Ravera E, Martelli T, Geiger Y, Fragai M, Goobes G, Luchinat C. Biosilica and bioinspired silica studied by solid-state NMR. Coord Chem Rev 2016. [DOI: 10.1016/j.ccr.2016.06.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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12
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Tang M, Mao K, Li S, Zhuang J, Diallo K. Paramagnetic effects on the NMR spectra of isotropic bicelles with headgroup modified chelator lipids and metal ions. Phys Chem Chem Phys 2016; 18:15524-7. [PMID: 27240538 DOI: 10.1039/c6cp01443g] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
We characterized the paramagnetic effects of nine metal ions on NMR signals of isotropic bicelles with headgroup-modified lipids. We found that Mn(2+), Gd(3+) and Dy(3+) show evidence for influencing NMR signals on the surface more than inside and on the disc edge, providing distance information in the bilayers.
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Affiliation(s)
- Ming Tang
- Department of Chemistry, College of Staten Island - PhD Program in Chemistry, The Graduate Center of the City University of New York, New York, NY 10016, USA.
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14
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Abstract
Specific conformations of signaling proteins can serve as “signals” in signal transduction by being recognized by receptors.
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Affiliation(s)
- Peter Tompa
- VIB Structural Biology Research Center (SBRC)
- Brussels
- Belgium
- Vrije Universiteit Brussel
- Brussels
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15
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Isotope Labeling of Eukaryotic Membrane Proteins in Yeast for Solid-State NMR. Methods Enzymol 2015; 565:193-212. [DOI: 10.1016/bs.mie.2015.05.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2023]
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