1
|
Weber DK, Reddy UV, Robia SL, Veglia G. Pathological mutations in the phospholamban cytoplasmic region affect its topology and dynamics modulating the extent of SERCA inhibition. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2024:184370. [PMID: 38986894 DOI: 10.1016/j.bbamem.2024.184370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Revised: 06/26/2024] [Accepted: 07/02/2024] [Indexed: 07/12/2024]
Abstract
Phospholamban (PLN) is a 52 amino acid regulin that allosterically modulates the activity of the sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA) in the heart muscle. In its unphosphorylated form, PLN binds SERCA within its transmembrane (TM) domains, approximately 20 Å away from the Ca2+ binding site, reducing SERCA's apparent Ca2+ affinity (pKCa) and decreasing cardiac contractility. During the enzymatic cycle, the inhibitory TM domain of PLN remains anchored to SERCA, whereas its cytoplasmic region transiently binds the ATPase's headpiece. Phosphorylation of PLN at Ser16 by protein kinase A increases the affinity of its cytoplasmic domain to SERCA, weakening the TM interactions with the ATPase, reversing its inhibitory function, and augmenting muscle contractility. How the structural changes caused by pathological mutations in the PLN cytoplasmic region are transmitted to its inhibitory TM domain is still unclear. Using solid-state NMR spectroscopy and activity assays, we analyzed structural and functional effects of a series of mutations and their phosphorylated forms located in the PLN cytoplasmic region and linked to dilated cardiomyopathy. We found that these missense mutations affect the overall topology and dynamics of PLN and ultimately modulate its inhibitory potency. Also, the changes in the TM tilt angle and cytoplasmic dynamics of PLN caused by these mutations correlate well with the extent of SERCA inhibition. Our study unveils new molecular determinants for designing variants of PLN that outcompete endogenous PLN to regulate SERCA in a tunable manner.
Collapse
Affiliation(s)
- Daniel K Weber
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - U Venkateswara Reddy
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Seth L Robia
- Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, IL, USA
| | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA.
| |
Collapse
|
2
|
Reddy UV, Weber DK, Wang S, Larsen EK, Gopinath T, De Simone A, Robia S, Veglia G. A kink in DWORF helical structure controls the activation of the sarcoplasmic reticulum Ca 2+-ATPase. Structure 2022; 30:360-370.e6. [PMID: 34875216 PMCID: PMC8897251 DOI: 10.1016/j.str.2021.11.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 09/14/2021] [Accepted: 11/11/2021] [Indexed: 12/31/2022]
Abstract
SERCA is a P-type ATPase embedded in the sarcoplasmic reticulum and plays a central role in muscle relaxation. SERCA's function is regulated by single-pass membrane proteins called regulins. Unlike other regulins, dwarf open reading frame (DWORF) expressed in cardiac muscle has a unique activating effect. Here, we determine the structure and topology of DWORF in lipid bilayers using a combination of oriented sample solid-state NMR spectroscopy and replica-averaged orientationally restrained molecular dynamics. We found that DWORF's structural topology consists of a dynamic N-terminal domain, an amphipathic juxtamembrane helix that crosses the lipid groups at an angle of 64°, and a transmembrane C-terminal helix with an angle of 32°. A kink induced by Pro15, unique to DWORF, separates the two helical domains. A single Pro15Ala mutant significantly decreases the kink and eliminates DWORF's activating effect on SERCA. Overall, our findings directly link DWORF's structural topology to its activating effect on SERCA.
Collapse
Affiliation(s)
- U. Venkateswara Reddy
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Daniel K. Weber
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Songlin Wang
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Erik K. Larsen
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, USA
| | - Tata Gopinath
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Alfonso De Simone
- Department of Life Sciences, Imperial College London, South Kensington, London, SW7 2AZ, UK,Department of Pharmacy, University of Naples “Federico II”, Naples, 80131, Italy
| | - Seth Robia
- Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, IL 60153, USA
| | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, 6-155 Jackson Hall, Minneapolis, MN 55455, USA; Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, USA.
| |
Collapse
|
3
|
Wang S, Gopinath T, Larsen EK, Weber DK, Walker C, Uddigiri VR, Mote KR, Sahoo SK, Periasamy M, Veglia G. Structural basis for sarcolipin's regulation of muscle thermogenesis by the sarcoplasmic reticulum Ca 2+-ATPase. SCIENCE ADVANCES 2021; 7:eabi7154. [PMID: 34826239 PMCID: PMC8626070 DOI: 10.1126/sciadv.abi7154] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 10/06/2021] [Indexed: 06/10/2023]
Abstract
The sarcoplasmic reticulum (SR) Ca2+-ATPase (SERCA) plays a central role in muscle contractility and nonshivering thermogenesis. SERCA is regulated by sarcolipin (SLN), a single-pass membrane protein that uncouples Ca2+ transport from ATP hydrolysis, promoting futile enzymatic cycles and heat generation. The molecular determinants for regulating heat release by the SERCA/SLN complex are unclear. Using thermocalorimetry, chemical cross-linking, and solid-state NMR spectroscopy in oriented phospholipid bicelles, we show that SERCA’s functional uncoupling and heat release rate are dictated by specific SERCA/SLN intramembrane interactions, with the carboxyl-terminal residues anchoring SLN to the SR membrane in an inhibitory topology. Systematic deletion of the carboxyl terminus does not prevent the SERCA/SLN complex formation but reduces uncoupling in a graded manner. These studies emphasize the critical role of lipids in defining the active topology of SLN and modulating the heat release rate by the SERCA/SLN complex, with implications in fat metabolism and basal metabolic rate.
Collapse
Affiliation(s)
- Songlin Wang
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Tata Gopinath
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Erik K. Larsen
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, USA
| | - Daniel K. Weber
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Caitlin Walker
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Venkateswara Reddy Uddigiri
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Kaustubh R. Mote
- Tata Institute of Fundamental Research Hyderabad, Survey No. 36/P Gopanpally, Serilingampally, Ranga Reddy District, Hyderabad, Telangana 500046, India
| | - Sanjaya K. Sahoo
- Department of Physiology, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Muthu Periasamy
- Department of Physiology, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
- Department of Internal Medicine, College of Medicine, University of Central Florida, Orlando, FL 32827, USA
| | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, USA
| |
Collapse
|
4
|
Weber DK, Reddy UV, Wang S, Larsen EK, Gopinath T, Gustavsson MB, Cornea RL, Thomas DD, De Simone A, Veglia G. Structural basis for allosteric control of the SERCA-Phospholamban membrane complex by Ca 2+ and phosphorylation. eLife 2021; 10:66226. [PMID: 33978571 PMCID: PMC8184213 DOI: 10.7554/elife.66226] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 05/10/2021] [Indexed: 01/26/2023] Open
Abstract
Phospholamban (PLN) is a mini-membrane protein that directly controls the cardiac Ca2+-transport response to β-adrenergic stimulation, thus modulating cardiac output during the fight-or-flight response. In the sarcoplasmic reticulum membrane, PLN binds to the sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA), keeping this enzyme's function within a narrow physiological window. PLN phosphorylation by cAMP-dependent protein kinase A or increase in Ca2+ concentration reverses the inhibitory effects through an unknown mechanism. Using oriented-sample solid-state NMR spectroscopy and replica-averaged NMR-restrained structural refinement, we reveal that phosphorylation of PLN's cytoplasmic regulatory domain signals the disruption of several inhibitory contacts at the transmembrane binding interface of the SERCA-PLN complex that are propagated to the enzyme's active site, augmenting Ca2+ transport. Our findings address long-standing questions about SERCA regulation, epitomizing a signal transduction mechanism operated by posttranslationally modified bitopic membrane proteins.
Collapse
Affiliation(s)
- Daniel K Weber
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, United States
| | - U Venkateswara Reddy
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, United States
| | - Songlin Wang
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, United States
| | - Erik K Larsen
- Department of Chemistry, University of Minnesota, Minneapolis, United States
| | - Tata Gopinath
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, United States
| | - Martin B Gustavsson
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, United States
| | - Razvan L Cornea
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, United States
| | - David D Thomas
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, United States
| | - Alfonso De Simone
- Department of Life Sciences, Imperial College London, South Kensington, London, United Kingdom.,Department of Pharmacy, University of Naples 'Federico II', Naples, Italy
| | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, United States.,Department of Chemistry, University of Minnesota, Minneapolis, United States
| |
Collapse
|
5
|
Perras FA, Paterson AL, Kobayashi T. Phase-sensitive γ-encoded recoupling of heteronuclear dipolar interactions and 1H chemical shift anisotropy. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2021; 111:101712. [PMID: 33450713 DOI: 10.1016/j.ssnmr.2020.101712] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 12/18/2020] [Accepted: 12/19/2020] [Indexed: 06/12/2023]
Abstract
γ-encoded recoupling sequences are known to produce strong amplitude modulations that lead to sharp doublets when Fourier transformed. These doublets depend very little on the recoupled tensor asymmetry and thus enable for the straightforward determination of dynamic order parameters. It can, however, be difficult to measure small anisotropies, or small order parameters, using such sequences; the resonances from the doublet may overlap with each other, or with the zero-frequency glitch. This limitation has prevented the widespread use of 1H chemical shift anisotropy (CSA) for the measurement of dynamics, particularly for CH protons which typically have CSAs of only a few ppm when immobile. Here, we introduce a simple modification to the traditional 1H CSA and proton-detected local field pulse sequences that enables the acquisition of a hypercomplex dataset and the removal of the uncorrelated magnetization that results in the zero-frequency glitch. These new sequences then yield a frequency shift in the indirect dimension, rather than a splitting, which is easily identifiable even in cases of weak interactions.
Collapse
|
6
|
Jeong JH, Kim M, Kim Y. NMR structural studies and mechanism of action of Lactophoricin analogs as antimicrobial peptides. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1863:183469. [PMID: 32871115 DOI: 10.1016/j.bbamem.2020.183469] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 08/18/2020] [Accepted: 08/26/2020] [Indexed: 11/16/2022]
Abstract
Antimicrobial peptides (AMPs) are effective alternatives to conventional antibiotics. They protect the host from the constant invasion of a broad range of infectious microorganisms. AMPs have been at the forefront of the response to multidrug-resistant microbial strains and appear to be ideal drug candidates. Lactophoricin (LPcin), naturally produced from bovine milk, is a typical cationic antimicrobial peptide. Three analog peptides, including LPcin-YK5, LPcin-YK8, and LPcin-YK11, with enhanced antimicrobial activity compared to the wild-type LPcin, were designed and expressed in our laboratory. We investigated the structure and antimicrobial mechanisms of action of the three novel antimicrobial peptide analogs derived from LPcin using solution NMR and solid-state NMR spectroscopy in membrane environments. Our results revealed that the three LPcin analogs exhibited helical structures with different tilt angles on the phospholipid membrane surface. We proposed three-dimensional conformations and antibacterial mechanisms of action of the three peptide analogs in the phospholipid bilayers using two-dimensional solid-state separated local field NMR experiments.
Collapse
Affiliation(s)
- Ji-Ho Jeong
- Department of Chemistry, Hankuk University of Foreign Studies, Yong-In 17035, Republic of Korea
| | - Minseon Kim
- Department of Chemistry, Hankuk University of Foreign Studies, Yong-In 17035, Republic of Korea
| | - Yongae Kim
- Department of Chemistry, Hankuk University of Foreign Studies, Yong-In 17035, Republic of Korea.
| |
Collapse
|
7
|
Wang S, Gopinath T, Veglia G. Improving the quality of oriented membrane protein spectra using heat-compensated separated local field experiments. JOURNAL OF BIOMOLECULAR NMR 2019; 73:617-624. [PMID: 31463642 PMCID: PMC6861693 DOI: 10.1007/s10858-019-00273-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 08/21/2019] [Indexed: 05/03/2023]
Abstract
Oriented sample solid-state NMR (OS-ssNMR) spectroscopy is a powerful technique to determine the topology of membrane proteins in oriented lipid bilayers. Separated local field (SLF) experiments are central to this technique as they provide first-order orientational restraints, i.e., dipolar couplings and anisotropic chemical shifts. Despite the use of low-E (or E-free) probes, the heat generated during the execution of 2D and 3D SLF pulse sequences causes sizeable line-shape distortions. Here, we propose a new heat-compensated SE-SAMPI4 (hcSE-SAMPI4) pulse sequence that holds the temperature constant for the duration of the experiment. This modification of the SE-SAMPI4 results in sharper and more intense resonances without line-shape distortions. The spectral improvements are even more apparent when paramagnetic relaxation agents are used to speed up data collection. We tested the hcSE-SAMPI4 pulse sequence on a single-span membrane protein, sarcolipin (SLN), reconstituted in magnetically aligned lipid bicelles. In addition to eliminating peak distortions, the hcSE-SAMPI4 experiment increased the average signal-to-noise ratio by 20% with respect to the original SE-SAMPI4.
Collapse
Affiliation(s)
- Songlin Wang
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN, 55455, USA
| | - T Gopinath
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN, 55455, USA.
- Department of Chemistry, University of Minnesota, Minneapolis, MN, 55455, USA.
| |
Collapse
|
8
|
Kupče Ē, Mote KR, Madhu PK. Experiments with direct detection of multiple FIDs. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2019; 304:16-34. [PMID: 31077929 DOI: 10.1016/j.jmr.2019.04.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 03/26/2019] [Accepted: 04/29/2019] [Indexed: 05/04/2023]
Abstract
Pulse schemes with direct observation of multiple free induction decays (FIDs) offer a dramatic increase in the spectral information content of NMR experiments and often yield substantial improvement in measurement sensitivity per unit time. Availability of multiple receivers on the state-of-the-art commercial spectrometers allows spectra from different nuclear species to be recorded in parallel routinely. Experiments with multi-FID detection have been designed with both, homonuclear and multinuclear acquisition. We provide a brief overview of such techniques designed for applications in liquid- and solid- state NMR as well as in hyperpolarized samples. Here we show how these techniques have led to design of experiments that allow structure elucidation of small molecules and resonance assignment in proteins from a single measurement. Probes with multiple RF micro-coils routed to multiple NMR receivers provide an alternative way of increasing the throughput of modern NMR systems. Solid-state NMR experiments have also benefited immensely from both parallel and simultaneous FID acquisition in a variety of multi-dimensional pulse schemes. We believe that multi-FID detection will become an essential component of the future NMR methodologies effectively increasing the information content of NMR experiments and reducing the cost of NMR analysis.
Collapse
Affiliation(s)
- Ēriks Kupče
- Bruker UK Ltd., Banner Lane, Coventry CV4 9GH, United Kingdom.
| | - Kaustubh R Mote
- TIFR Centre for Interdisciplinary Sciences, Tata Institute of Fundamental Research Hyderabad, 36/P Gopanpally Village, Ranga Reddy District, Hyderabad 500107, India
| | - Perunthiruthy K Madhu
- TIFR Centre for Interdisciplinary Sciences, Tata Institute of Fundamental Research Hyderabad, 36/P Gopanpally Village, Ranga Reddy District, Hyderabad 500107, India
| |
Collapse
|
9
|
Wang S, Gopinath T, Veglia G. Application of paramagnetic relaxation enhancements to accelerate the acquisition of 2D and 3D solid-state NMR spectra of oriented membrane proteins. Methods 2017; 138-139:54-61. [PMID: 29274874 DOI: 10.1016/j.ymeth.2017.12.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 12/14/2017] [Accepted: 12/19/2017] [Indexed: 12/21/2022] Open
Abstract
Oriented sample solid-state NMR (OS-ssNMR) spectroscopy is uniquely suited to determine membrane protein topology at the atomic resolution in liquid crystalline bilayers under physiological temperature. However, the inherent low sensitivity of this technique has hindered the throughput of multidimensional experiments necessary for resonance assignments and structure determination. In this work, we show that doping membrane protein bicelle preparations with paramagnetic ion chelated lipids and exploiting paramagnetic relaxation effects it is possible to accelerate the acquisition of both 2D and 3D multidimensional experiments with significant saving in time. We demonstrate the efficacy of this method for a small membrane protein, sarcolipin, reconstituted in DMPC/POPC/DHPC oriented bicelles. In particular, using Cu2+-DMPE-DTPA as a dopant, we observed a decrease of 1H T1 of sarcolipin by 2/3, allowing us to reduce the recycle delay up to 3 times. We anticipate that these new developments will enable the routine acquisition of multidimensional OS-ssNMR experiments.
Collapse
Affiliation(s)
- Songlin Wang
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, United States
| | - T Gopinath
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, United States
| | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, United States; Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, United States.
| |
Collapse
|
10
|
Dicke A, Gopinath T, Wang Y, Veglia G. Probing Residue-Specific Water-Protein Interactions in Oriented Lipid Membranes via Solid-State NMR Spectroscopy. J Phys Chem B 2016; 120:10959-10968. [PMID: 27704861 DOI: 10.1021/acs.jpcb.6b08282] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Water plays a central role in membrane protein folding and function. It not only catalyzes lipid membrane self-assembly but also affects the structural integrity and conformational dynamics of membrane proteins. Magic angle spinning (MAS) solid-state NMR (ssNMR) is the technique of choice for measuring water accessibility of membrane proteins, providing a measure for membrane protein topology and insertion within lipid bilayers. However, the sensitivity and resolution of membrane protein samples for MAS experiments are often dictated by hydration levels, which affect the structural dynamics of membrane proteins. Oriented-sample ssNMR (OS-ssNMR) is a complementary technique to determine both structure and topology of membrane proteins in liquid crystalline bilayers. Recent advancements in OS-ssNMR involve the use of oriented bicellar phases that have improved both sensitivity and resolution. Importantly, for bicelle formation and orientation, lipid bilayers must be well organized and hydrated, resulting in the protein's topology being similar to that found in native membranes. Under these conditions, the NMR resonances become relatively narrow, enabling a better separation of 1H-15N dipolar couplings and anisotropic 15N chemical shifts with separated local field (SLF) experiments. Here, we report a residue-specific water accessibility experiment for a small membrane protein, sarcolipin (SLN), embedded in oriented lipid bicelles as probed by new water-edited SLF (WE-SLF) experiments. We show that SLN's residues belonging to the juxtamembrane region are more exposed to the water-lipid interface than the corresponding membrane-embedded residues. The information that can be obtained from the WE-SLF experiments can be interpreted using a simple theoretical model based on spin-diffusion theory and offers a complete characterization of membrane proteins in realistic membrane bilayer systems.
Collapse
Affiliation(s)
- Alysha Dicke
- Department of Biochemistry, Molecular Biology, and Biophysics and ‡Department of Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - T Gopinath
- Department of Biochemistry, Molecular Biology, and Biophysics and ‡Department of Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Yingjie Wang
- Department of Biochemistry, Molecular Biology, and Biophysics and ‡Department of Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology, and Biophysics and ‡Department of Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States
| |
Collapse
|
11
|
Martin RW, Kelly JE, Collier KA. Spatial reorientation experiments for NMR of solids and partially oriented liquids. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2015; 90-91:92-122. [PMID: 26592947 PMCID: PMC6936739 DOI: 10.1016/j.pnmrs.2015.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2015] [Revised: 10/13/2015] [Accepted: 10/15/2015] [Indexed: 06/05/2023]
Abstract
Motional reorientation experiments are extensions of Magic Angle Spinning (MAS) where the rotor axis is changed in order to average out, reintroduce, or scale anisotropic interactions (e.g. dipolar couplings, quadrupolar interactions or chemical shift anisotropies). This review focuses on Variable Angle Spinning (VAS), Switched Angle Spinning (SAS), and Dynamic Angle Spinning (DAS), all of which involve spinning at two or more different angles sequentially, either in successive experiments or during a multidimensional experiment. In all of these experiments, anisotropic terms in the Hamiltonian are scaled by changing the orientation of the spinning sample relative to the static magnetic field. These experiments vary in experimental complexity and instrumentation requirements. In VAS, many one-dimensional spectra are collected as a function of spinning angle. In SAS, dipolar couplings and/or chemical shift anisotropies are reintroduced by switching the sample between two different angles, often 0° or 90° and the magic angle, yielding a two-dimensional isotropic-anisotropic correlation spectrum. Dynamic Angle Spinning (DAS) is a related experiment that is used to simultaneously average out the first- and second-order quadrupolar interactions, which cannot be accomplished by spinning at any unique rotor angle in physical space. Although motional reorientation experiments generally require specialized instrumentation and data analysis schemes, some are accessible with only minor modification of standard MAS probes. In this review, the mechanics of each type of experiment are described, with representative examples. Current and historical probe and coil designs are discussed from the standpoint of how each one accomplishes the particular objectives of the experiment(s) it was designed to perform. Finally, applications to inorganic materials and liquid crystals, which present very different experimental challenges, are discussed. The review concludes with perspectives on how motional reorientation experiments can be applied to current problems in chemistry, molecular biology, and materials science, given the many advances in high-field NMR magnets, fast spinning, and sample preparation realized in recent years.
Collapse
Affiliation(s)
- Rachel W Martin
- Department of Chemistry, University of California, Irvine 92697-2025, United States; Department of Molecular Biology and Biochemistry, University of California, Irvine 92697-3900, United States.
| | - John E Kelly
- Department of Chemistry, University of California, Irvine 92697-2025, United States
| | - Kelsey A Collier
- Department of Physics and Astronomy, University of California, Irvine 92697-4575, United States
| |
Collapse
|
12
|
Hansen SK, Bertelsen K, Paaske B, Nielsen NC, Vosegaard T. Solid-state NMR methods for oriented membrane proteins. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2015; 88-89:48-85. [PMID: 26282196 DOI: 10.1016/j.pnmrs.2015.05.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 04/27/2015] [Indexed: 06/04/2023]
Abstract
Oriented-sample solid-state NMR represents one of few experimental methods capable of characterising the membrane-bound conformation of proteins in the cell membrane. Since the technique was developed 25 years ago, the technique has been applied to study the structure of helix bundle membrane proteins and antimicrobial peptides, characterise protein-lipid interactions, and derive information on dynamics of the membrane anchoring of membrane proteins. We will review the major developments in various aspects of oriented-sample solid-state NMR, including sample-preparation methods, pulse sequences, theory required to interpret the experiments, perspectives for and guidelines to new experiments, and a number of representative applications.
Collapse
Affiliation(s)
- Sara K Hansen
- Center for Insoluble Protein Structures (inSPIN), Interdisciplinary Nanoscience Center (iNANO), Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, DK-8000 Aarhus C, Denmark
| | - Kresten Bertelsen
- Center for Insoluble Protein Structures (inSPIN), Interdisciplinary Nanoscience Center (iNANO), Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, DK-8000 Aarhus C, Denmark
| | - Berit Paaske
- Center for Insoluble Protein Structures (inSPIN), Interdisciplinary Nanoscience Center (iNANO), Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, DK-8000 Aarhus C, Denmark
| | - Niels Chr Nielsen
- Center for Insoluble Protein Structures (inSPIN), Interdisciplinary Nanoscience Center (iNANO), Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, DK-8000 Aarhus C, Denmark
| | - Thomas Vosegaard
- Center for Insoluble Protein Structures (inSPIN), Interdisciplinary Nanoscience Center (iNANO), Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, DK-8000 Aarhus C, Denmark.
| |
Collapse
|
13
|
Gopinath T, Mote KR, Veglia G. Simultaneous acquisition of 2D and 3D solid-state NMR experiments for sequential assignment of oriented membrane protein samples. JOURNAL OF BIOMOLECULAR NMR 2015; 62:53-61. [PMID: 25749871 PMCID: PMC4981477 DOI: 10.1007/s10858-015-9916-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 03/03/2015] [Indexed: 05/20/2023]
Abstract
We present a new method called DAISY (Dual Acquisition orIented ssNMR spectroScopY) for the simultaneous acquisition of 2D and 3D oriented solid-state NMR experiments for membrane proteins reconstituted in mechanically or magnetically aligned lipid bilayers. DAISY utilizes dual acquisition of sine and cosine dipolar or chemical shift coherences and long living (15)N longitudinal polarization to obtain two multi-dimensional spectra, simultaneously. In these new experiments, the first acquisition gives the polarization inversion spin exchange at the magic angle (PISEMA) or heteronuclear correlation (HETCOR) spectra, the second acquisition gives PISEMA-mixing or HETCOR-mixing spectra, where the mixing element enables inter-residue correlations through (15)N-(15)N homonuclear polarization transfer. The analysis of the two 2D spectra (first and second acquisitions) enables one to distinguish (15)N-(15)N inter-residue correlations for sequential assignment of membrane proteins. DAISY can be implemented in 3D experiments that include the polarization inversion spin exchange at magic angle via I spin coherence (PISEMAI) sequence, as we show for the simultaneous acquisition of 3D PISEMAI-HETCOR and 3D PISEMAI-HETCOR-mixing experiments.
Collapse
Affiliation(s)
| | | | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455
- Department of Chemistry and University of Minnesota, Minneapolis, MN 55455
- Corresponding Author. Gianluigi Veglia, 6-155 Jackson Hall, 321 Church St SE, Minneapolis, MN 55455, Phone: (612) 625-0758, Fax: (612) 625-2163,
| |
Collapse
|
14
|
Gopinath T, Veglia G. Orphan spin operators enable the acquisition of multiple 2D and 3D magic angle spinning solid-state NMR spectra. J Chem Phys 2013; 138:184201. [PMID: 23676036 DOI: 10.1063/1.4803126] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
We propose a general method that enables the acquisition of multiple 2D and 3D solid-state NMR spectra for U-(13)C, (15)N-labeled proteins. This method, called MEIOSIS (Multiple ExperIments via Orphan SpIn operatorS), makes it possible to detect four coherence transfer pathways simultaneously, utilizing orphan (i.e., neglected) spin operators of nuclear spin polarization generated during (15)N-(13)C cross polarization (CP). In the MEIOSIS experiments, two phase-encoded free-induction decays are decoded into independent nuclear polarization pathways using Hadamard transformations. As a proof of principle, we show the acquisition of multiple 2D and 3D spectra of U-(13)C, (15)N-labeled microcrystalline ubiquitin. Hadamard decoding of CP coherences into multiple independent spin operators is a new concept in solid-state NMR and is extendable to many other multidimensional experiments. The MEIOSIS method will increase the throughput of solid-state NMR techniques for microcrystalline proteins, membrane proteins, and protein fibrils.
Collapse
Affiliation(s)
- T Gopinath
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | | |
Collapse
|
15
|
Gopinath T, Mote KR, Veglia G. Sensitivity and resolution enhancement of oriented solid-state NMR: application to membrane proteins. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2013; 75:50-68. [PMID: 24160761 PMCID: PMC3850070 DOI: 10.1016/j.pnmrs.2013.07.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 06/16/2013] [Indexed: 05/19/2023]
Abstract
Oriented solid-state NMR (O-ssNMR) spectroscopy is a major technique for the high-resolution analysis of the structure and topology of transmembrane proteins in native-like environments. Unlike magic angle spinning (MAS) techniques, O-ssNMR spectroscopy requires membrane protein preparations that are uniformly oriented (mechanically or magnetically) so that anisotropic NMR parameters, such as dipolar and chemical shift interactions, can be measured to determine structure and orientation of membrane proteins in lipid bilayers. Traditional sample preparations involving mechanically aligned lipids often result in short relaxation times which broaden the (15)N resonances and encumber the manipulation of nuclear spin coherences. The introduction of lipid bicelles as membrane mimicking systems has changed this scenario, and the more favorable relaxation properties of membrane protein (15)N and (13)C resonances make it possible to develop new, more elaborate pulse sequences for higher spectral resolution and sensitivity. Here, we describe our recent progress in the optimization of O-ssNMR pulse sequences. We explain the theory behind these experiments, demonstrate their application to small and medium size proteins, and describe the technical details for setting up these new experiments on the new generation of NMR spectrometers.
Collapse
Affiliation(s)
- T. Gopinath
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, United States
| | - Kaustubh R. Mote
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, United States
| | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, United States
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, United States
| |
Collapse
|
16
|
Mote KR, Gopinath T, Veglia G. Determination of structural topology of a membrane protein in lipid bilayers using polarization optimized experiments (POE) for static and MAS solid state NMR spectroscopy. JOURNAL OF BIOMOLECULAR NMR 2013; 57:91-102. [PMID: 23963722 PMCID: PMC3883141 DOI: 10.1007/s10858-013-9766-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 07/26/2013] [Indexed: 05/11/2023]
Abstract
The low sensitivity inherent to both the static and magic angle spinning techniques of solid-state NMR (ssNMR) spectroscopy has thus far limited the routine application of multidimensional experiments to determine the structure of membrane proteins in lipid bilayers. Here, we demonstrate the advantage of using a recently developed class of experiments, polarization optimized experiments, for both static and MAS spectroscopy to achieve higher sensitivity and substantial time-savings for 2D and 3D experiments. We used sarcolipin, a single pass membrane protein, reconstituted in oriented bicelles (for oriented ssNMR) and multilamellar vesicles (for MAS ssNMR) as a benchmark. The restraints derived by these experiments are then combined into a hybrid energy function to allow simultaneous determination of structure and topology. The resulting structural ensemble converged to a helical conformation with a backbone RMSD ~0.44 Å, a tilt angle of 24° ± 1°, and an azimuthal angle of 55° ± 6°. This work represents a crucial first step toward obtaining high-resolution structures of large membrane proteins using combined multidimensional oriented solid-state NMR and magic angle spinning solid-state NMR.
Collapse
Affiliation(s)
- Kaustubh R. Mote
- Department of Chemistry University of Minnesota, Minneapolis, MN 55455, USA
| | - T. Gopinath
- Department of Biochemistry, Molecular Biology & Biophysics University of Minnesota, Minneapolis, MN 55455, USA
| | - Gianluigi Veglia
- Department of Chemistry University of Minnesota, Minneapolis, MN 55455, USA
- Department of Biochemistry, Molecular Biology & Biophysics University of Minnesota, Minneapolis, MN 55455, USA
| |
Collapse
|
17
|
Murray DT, Das N, Cross TA. Solid state NMR strategy for characterizing native membrane protein structures. Acc Chem Res 2013; 46:2172-81. [PMID: 23470103 DOI: 10.1021/ar3003442] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Unlike water soluble proteins, the structures of helical transmembrane proteins depend on a very complex environment. These proteins sit in the midst of dramatic electrical and chemical gradients and are often subject to variations in the lateral pressure profile, order parameters, dielectric constant, and other properties. Solid state NMR is a collection of tools that can characterize high resolution membrane protein structure in this environment. Indeed, prior work has shown that this complex environment significantly influences transmembrane protein structure. Therefore, it is important to characterize such structures under conditions that closely resemble its native environment. Researchers have used two approaches to gain protein structural restraints via solid state NMR spectroscopy. The more traditional approach uses magic angle sample spinning to generate isotropic chemical shifts, much like solution NMR. As with solution NMR, researchers can analyze the backbone chemical shifts to obtain torsional restraints. They can also examine nuclear spin interactions between nearby atoms to obtain distances between atomic sites. Unfortunately, for membrane proteins in lipid preparations, the spectral resolution is not adequate to obtain complete resonance assignments. Researchers have developed another approach for gaining structural restraints from membrane proteins: the use of uniformly oriented lipid bilayers, which provides a method for obtaining high resolution orientational restraints. When the bilayers are aligned with respect to the magnetic field of the NMR spectrometer, researchers can obtain orientational restraints in which atomic sites in the protein are restrained relative to the alignment axis. However, this approach does not allow researchers to determine the relative packing between helices. By combining the two approaches, we can take advantage of the information acquired from each technique to minimize the challenges and maximize the quality of the structural results. By combining the distance, torsional, and orientational restraints, we can characterize high resolution membrane protein structure in native-like lipid bilayer environments.
Collapse
Affiliation(s)
- Dylan T. Murray
- Institute of Molecular Biophysics, Department of Chemistry and Biochemistry, and National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, United States
| | - Nabanita Das
- Institute of Molecular Biophysics, Department of Chemistry and Biochemistry, and National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, United States
| | - Timothy A. Cross
- Institute of Molecular Biophysics, Department of Chemistry and Biochemistry, and National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, United States
| |
Collapse
|
18
|
Miao Y, Cross TA, Fu R. Identifying inter-residue resonances in crowded 2D (13)C- (13)C chemical shift correlation spectra of membrane proteins by solid-state MAS NMR difference spectroscopy. JOURNAL OF BIOMOLECULAR NMR 2013; 56:265-73. [PMID: 23708936 PMCID: PMC3717563 DOI: 10.1007/s10858-013-9745-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Accepted: 05/14/2013] [Indexed: 05/11/2023]
Abstract
The feasibility of using difference spectroscopy, i.e. subtraction of two correlation spectra at different mixing times, for substantially enhanced resolution in crowded two-dimensional (13)C-(13)C chemical shift correlation spectra is presented. With the analyses of (13)C-(13)C spin diffusion in simple spin systems, difference spectroscopy is proposed to partially separate the spin diffusion resonances of relatively short intra-residue distances from the longer inter-residue distances, leading to a better identification of the inter-residue resonances. Here solid-state magic-angle-spinning NMR spectra of the full length M2 protein embedded in synthetic lipid bilayers have been used to illustrate the resolution enhancement in the difference spectra. The integral membrane M2 protein of Influenza A virus assembles as a tetrameric bundle to form a proton-conducting channel that is activated by low pH and is essential for the viral lifecycle. Based on known amino acid resonance assignments from amino acid specific labeled samples of truncated M2 sequences or from time-consuming 3D experiments of uniformly labeled samples, some inter-residue resonances of the full length M2 protein can be identified in the difference spectra of uniformly (13)C labeled protein that are consistent with the high resolution structure of the M2 (22-62) protein (Sharma et al., Science 330(6003):509-512, 2010).
Collapse
Affiliation(s)
- Yimin Miao
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32310, USA
| | - Timothy A. Cross
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32310, USA
- National High Magnet Field Lab, 1800 East Paul Dirac Drive, Tallahassee, Florida 32310, USA
| | - Riqiang Fu
- National High Magnet Field Lab, 1800 East Paul Dirac Drive, Tallahassee, Florida 32310, USA
- Corresponding author: Riqiang Fu (), 1800 East Paul Dirac Drive, Tallahassee, FL 32310, Tel: +1 850 644 5044, Fax: +1 850 644 1366
| |
Collapse
|
19
|
Dürr UN, Gildenberg M, Ramamoorthy A. The magic of bicelles lights up membrane protein structure. Chem Rev 2012; 112:6054-74. [PMID: 22920148 PMCID: PMC3497859 DOI: 10.1021/cr300061w] [Citation(s) in RCA: 266] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Indexed: 12/12/2022]
Affiliation(s)
| | - Melissa Gildenberg
- Biophysics
and Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109-1055,
United States
| | - Ayyalusamy Ramamoorthy
- Biophysics
and Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109-1055,
United States
| |
Collapse
|
20
|
Gopinath T, Veglia G. 3D DUMAS: simultaneous acquisition of three-dimensional magic angle spinning solid-state NMR experiments of proteins. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2012; 220:79-84. [PMID: 22698806 PMCID: PMC3487463 DOI: 10.1016/j.jmr.2012.04.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 04/13/2012] [Indexed: 05/15/2023]
Abstract
Using the DUMAS (Dual acquisition Magic Angle Spinning) solid-state NMR approach, we created new pulse schemes that enable the simultaneous acquisition of three dimensional (3D) experiments on uniformly (13)C, (15)N labeled proteins. These new experiments exploit the simultaneous cross-polarization (SIM-CP) from (1)H to (13)C and (15)N to acquire two 3D experiments simultaneously. This is made possible by bidirectional polarization transfer between (13)C and (15)N and the long living (15)N z-polarization in solid state NMR. To demonstrate the power of this approach, four 3D pulse sequences (NCACX, CANCO, NCOCX, CON(CA)CX) are combined into two pulse sequences (3D DUMAS-NCACX-CANCO, 3D DUMAS-NCOCX-CON(CA)CX) that allow simultaneous acquisition of these experiments, reducing the experimental time by approximately half. Importantly, the 3D DUMAS-NCACX-CANCO experiment alone makes it possible to obtain the majority of the backbone sequential resonance assignments for microcrystalline U-(13)C,(15)N ubiquitin. The DUMAS approach is general and applicable to many 3D experiments, nearly doubling the performance of NMR spectrometers.
Collapse
Affiliation(s)
- T. Gopinath
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455
| | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455
| |
Collapse
|
21
|
Banigan JR, Traaseth NJ. Utilizing afterglow magnetization from cross-polarization magic-angle-spinning solid-state NMR spectroscopy to obtain simultaneous heteronuclear multidimensional spectra. J Phys Chem B 2012; 116:7138-44. [PMID: 22582831 PMCID: PMC3418334 DOI: 10.1021/jp303269m] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The time required for data acquisition and subsequent spectral assignment are limiting factors for determining biomolecular structure and dynamics using solid-state NMR spectroscopy. While strong magnetic dipolar couplings give rise to relatively broad spectra lines, the couplings also mediate the coherent magnetization transfer via the Hartmann-Hahn cross-polarization (HH-CP) experiment. This mechanism is used in nearly all backbone assignment experiments for carrying out polarization transfer between (1)H, (15)N, and (13)C. In this Article, we describe a general spectroscopic approach to use the residual or "afterglow" magnetization from the (15)N to (13)C selective HH-CP experiment to collect a second multidimensional heteronuclear data set. This approach allowed for the collection of two commonly used sequential assignment experiments (2D NCA and NCO or 3D NCACX and NCOCX) at the same time. Our "afterglow" technique was demonstrated with uniformly [(13)C,(15)N] and [1,3-(13)C] glycerol-labeled ubiquitin using instrumentation available on all standard solid-state NMR spectrometers configured for magic-angle-spinning. This method is compatible with several other sensitivity enhancement experiments and can be used as an isotopic filtering tool to reduce the spectral complexity and decrease the time needed for assignment.
Collapse
Affiliation(s)
- James R. Banigan
- Department of Chemistry, New York University, New York, NY 10003
| | | |
Collapse
|
22
|
Gopinath T, Veglia G. Dual acquisition magic-angle spinning solid-state NMR-spectroscopy: simultaneous acquisition of multidimensional spectra of biomacromolecules. Angew Chem Int Ed Engl 2012; 51:2731-5. [PMID: 22311700 PMCID: PMC3513283 DOI: 10.1002/anie.201108132] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Indexed: 11/05/2022]
Abstract
Fast data collection: a general method for dual data acquisition of multidimensional magic-angle spinning solid-state NMR experiments is presented. The method uses a simultaneous Hartmann-Hahn cross-polarization from (1)H to (13)C and (15)N nuclei and exploits the long-living (15)N polarization for parallel acquisition of two multidimensional experiments.
Collapse
Affiliation(s)
- T. Gopinath
- Department of Chemistry and Department of Biochemistry, Molecular Biology and Biophysics, 321 Church St. SE, Minneapolis, MN 55455 USA
| | - Gianluigi Veglia
- Department of Chemistry and Department of Biochemistry, Molecular Biology and Biophysics, 321 Church St. SE, Minneapolis, MN 55455 USA
| |
Collapse
|
23
|
Gopinath T, Veglia G. Dual Acquisition Magic-Angle Spinning Solid-State NMR-Spectroscopy: Simultaneous Acquisition of Multidimensional Spectra of Biomacromolecules. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201108132] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
|
24
|
Gopinath T, Mote KR, Veglia G. Proton evolved local field solid-state nuclear magnetic resonance using Hadamard encoding: theory and application to membrane proteins. J Chem Phys 2011; 135:074503. [PMID: 21861572 DOI: 10.1063/1.3622604] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
NMR anisotropic parameters such as dipolar couplings and chemical shifts are central to structure and orientation determination of aligned membrane proteins and liquid crystals. Among the separated local field experiments, the proton evolved local field (PELF) scheme is particularly suitable to measure dynamically averaged dipolar couplings and give information on local molecular motions. However, the PELF experiment requires the acquisition of several 2D datasets at different mixing times to optimize the sensitivity for the complete range of dipolar couplings of the resonances in the spectrum. Here, we propose a new PELF experiment that takes the advantage of the Hadamard encoding (HE) to obtain higher sensitivity for a broad range of dipolar couplings using a single 2D experiment. The HE scheme is obtained by selecting the spin operators with phase switching of hard pulses. This approach enables one to detect four spin operators, simultaneously, which can be processed into two 2D spectra covering a broader range of dipolar couplings. The advantages of the new approach are illustrated for a U-(15)N NAL single crystal and the U-(15)N labeled single-pass membrane protein sarcolipin reconstituted in oriented lipid bicelles. The HE-PELF scheme can be implemented in other multidimensional experiments to speed up the characterization of the structure and dynamics of oriented membrane proteins and liquid crystalline samples.
Collapse
Affiliation(s)
- T Gopinath
- Department of Biochemistry, Molecular Biology, and Biophysics, Minneapolis, Minnesota 55455, USA
| | | | | |
Collapse
|
25
|
Mote KR, Gopinath T, Traaseth NJ, Kitchen J, Gor'kov PL, Brey WW, Veglia G. Multidimensional oriented solid-state NMR experiments enable the sequential assignment of uniformly 15N labeled integral membrane proteins in magnetically aligned lipid bilayers. JOURNAL OF BIOMOLECULAR NMR 2011; 51:339-346. [PMID: 21976256 DOI: 10.1007/s10858-011-9571-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Accepted: 08/11/2011] [Indexed: 05/31/2023]
Abstract
Oriented solid-state NMR is the most direct methodology to obtain the orientation of membrane proteins with respect to the lipid bilayer. The method consists of measuring (1)H-(15)N dipolar couplings (DC) and (15)N anisotropic chemical shifts (CSA) for membrane proteins that are uniformly aligned with respect to the membrane bilayer. A significant advantage of this approach is that tilt and azimuthal (rotational) angles of the protein domains can be directly derived from analytical expression of DC and CSA values, or, alternatively, obtained by refining protein structures using these values as harmonic restraints in simulated annealing calculations. The Achilles' heel of this approach is the lack of suitable experiments for sequential assignment of the amide resonances. In this Article, we present a new pulse sequence that integrates proton driven spin diffusion (PDSD) with sensitivity-enhanced PISEMA in a 3D experiment ([(1)H,(15)N]-SE-PISEMA-PDSD). The incorporation of 2D (15)N/(15)N spin diffusion experiments into this new 3D experiment leads to the complete and unambiguous assignment of the (15)N resonances. The feasibility of this approach is demonstrated for the membrane protein sarcolipin reconstituted in magnetically aligned lipid bicelles. Taken with low electric field probe technology, this approach will propel the determination of sequential assignment as well as structure and topology of larger integral membrane proteins in aligned lipid bilayers.
Collapse
Affiliation(s)
- Kaustubh R Mote
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455-0431, USA
| | | | | | | | | | | | | |
Collapse
|
26
|
Traaseth NJ, Gopinath T, Veglia G. On the performance of spin diffusion NMR techniques in oriented solids: prospects for resonance assignments and distance measurements from separated local field experiments. J Phys Chem B 2010; 114:13872-80. [PMID: 20936833 PMCID: PMC3000634 DOI: 10.1021/jp105718r] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
NMR spin diffusion experiments have the potential to provide both resonance assignment and internuclear distances for protein structure determination in oriented solid-state NMR. In this paper, we compared the efficiencies of three spin diffusion experiments: proton-driven spin diffusion (PDSD), cross-relaxation-driven spin diffusion (CRDSD), and proton-mediated proton transfer (PMPT). As model systems for oriented proteins, we used single crystals of N-acetyl-L-(15)N-leucine (NAL) and N-acetyl-L-(15)N-valyl-L-(15)N-leucine (NAVL) to probe long and short distances, respectively. We demonstrate that, for short (15)N/(15)N distances such as those found in NAVL (3.3 Å), the PDSD mechanism gives the most intense cross-peaks, while, for longer distances (>6.5 Å), the CRDSD and PMPT experiments are more efficient. The PDSD was highly inefficient for transferring magnetization across distances greater than 6.5 Å (NAL crystal sample), due to small (15)N/(15)N dipolar couplings (<4.5 Hz). Interestingly, the mismatched Hartmann-Hahn condition present in the PMPT experiment gave more intense cross-peaks for lower (1)H and (15)N RF spinlock amplitudes (32 and 17 kHz, respectively) rather than higher values (55 and 50 kHz), suggesting a more complex magnetization transfer mechanism. Numerical simulations are in good agreement with the experimental findings, suggesting a combined PMPT and CRDSD effect. We conclude that, in order to assign SLF spectra and measure short- and long-range distances, the combined use of homonuclear correlation spectra, such as the ones surveyed in this work, are necessary.
Collapse
Affiliation(s)
- Nathaniel J Traaseth
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | | | | |
Collapse
|
27
|
Gopinath T, Veglia G. Improved Resolution in Dipolar NMR Spectra Using Constant Time Evolution PISEMA Experiment. Chem Phys Lett 2010; 494:104-110. [PMID: 20814452 PMCID: PMC2929988 DOI: 10.1016/j.cplett.2010.05.078] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The atomic structure of small molecules and polypeptides can be attained from anisotropic NMR parameters such as dipolar couplings (DC) and chemical shifts (CS). Separated local field experiments resolve DC and CS correlations into two dimensions. However, crowded NMR spectra represent a significant obstacle for the complete resolution of these anisotropic parameters. Using the PISEMA (Polarization Inversion Spin Exchange at the Magic Angle) experiment as a foundation, we designed new pulse schemes that use a constant time evolution in the dipolar (indirect) dimension to measure DC and CS correlations at high resolution. We demonstrated this approach on a 4-pentyl-4'-cyanobiphenyl (5CB) liquid crystal sample, achieving a resolution enhancement ranging from 30 to 60 % for the resonances in the dipolar dimension. These new experiments open the possibility of obtaining significant resolution enhancement for multidimensional NMR experiments carried out on oriented liquid crystalline samples as well as oriented membrane proteins.
Collapse
Affiliation(s)
- T. Gopinath
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455
| | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455
| |
Collapse
|
28
|
Gopinath T, Traaseth NJ, Mote K, Veglia G. Sensitivity enhanced heteronuclear correlation spectroscopy in multidimensional solid-state NMR of oriented systems via chemical shift coherences. J Am Chem Soc 2010; 132:5357-63. [PMID: 20345172 PMCID: PMC3328406 DOI: 10.1021/ja905991s] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present new sensitivity enhanced schemes for heteronuclear correlation spectroscopy (HETCOR) in solid-state NMR of oriented systems. These schemes will enhance the sensitivity of the HETCOR by 40% for the two-dimensional experiments (SE-HETCOR) and up to 180% for the 3D HETCOR-separated local field version (SE-PISEMAI-HETCOR). The signal enhancement is demonstrated for a single crystal of ((15)N)N-acetylleucine and the integral membrane protein sarcolipin oriented in lipid bicelles. These methods will significantly reduce the time needed to acquire multidimensional experiments for membrane proteins oriented in magnetically or mechanically aligned lipid bilayers as well as liquid crystalline materials.
Collapse
Affiliation(s)
- T. Gopinath
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455
| | | | - Kaustubh Mote
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455
| | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455
| |
Collapse
|