1
|
Li M, Mandal A, Tyurin VA, DeLucia M, Ahn J, Kagan VE, van der Wel PCA. Surface-Binding to Cardiolipin Nanodomains Triggers Cytochrome c Pro-apoptotic Peroxidase Activity via Localized Dynamics. Structure 2019; 27:806-815.e4. [PMID: 30879887 DOI: 10.1016/j.str.2019.02.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 01/16/2019] [Accepted: 02/15/2019] [Indexed: 02/06/2023]
Abstract
The peroxidation of cardiolipins by reactive oxygen species, which is regulated and enhanced by cytochrome c (cyt c), is a critical signaling event in mitochondrial apoptosis. We probe the molecular underpinnings of this mitochondrial death signal through structural and functional studies of horse heart cyt c binding to mixed-lipid membranes containing cardiolipin with mono- and polyunsaturated acyl chains. Lipidomics reveal the selective oxidation of polyunsaturated fatty acid (PUFA) cardiolipin (CL), while multidimensional solid-state NMR probes the structure and dynamics of the membrane and the peripherally bound protein. The hydrophilic milieu at the membrane interface stabilizes a native-like fold, but also leads to localized flexibility at the membrane-interacting protein face. PUFA CL acts as both a preferred substrate and a dynamic regulator by affecting the dynamics of the cyt c N70-I85 Ω loop, which covers the heme cavity.
Collapse
Affiliation(s)
- Mingyue Li
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Abhishek Mandal
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Vladimir A Tyurin
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Maria DeLucia
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Jinwoo Ahn
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Valerian E Kagan
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, PA 15213, USA; Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15213, USA; Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA; Department of Radiation Oncology, University of Pittsburgh, Pittsburgh, PA 15213, USA; Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, PA 15213, USA; Laboratory of Navigational Redox Lipidomics, IM Sechenov Moscow State Medical University, Moscow 119146, Russian Federation
| | - Patrick C A van der Wel
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA; Zernike Institute for Advanced Materials, University of Groningen, 9747 AG Groningen, The Netherlands.
| |
Collapse
|
2
|
Salnikov ES, Aisenbrey C, Anantharamaiah G, Bechinger B. Solid-state NMR structural investigations of peptide-based nanodiscs and of transmembrane helices in bicellar arrangements. Chem Phys Lipids 2019; 219:58-71. [DOI: 10.1016/j.chemphyslip.2019.01.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 01/29/2019] [Accepted: 01/29/2019] [Indexed: 02/08/2023]
|
3
|
Gopinath T, Veglia G. Probing membrane protein ground and conformationally excited states using dipolar- and J-coupling mediated MAS solid state NMR experiments. Methods 2018; 148:115-122. [PMID: 30012515 PMCID: PMC6428079 DOI: 10.1016/j.ymeth.2018.07.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 07/10/2018] [Accepted: 07/11/2018] [Indexed: 12/25/2022] Open
Abstract
The intrinsic conformational plasticity of membrane proteins directly influences the magnitude of the orientational-dependent NMR interactions such as dipolar couplings (DC) and chemical shift anisotropy (CSA). As a result, the conventional cross-polarization (CP)-based techniques mainly capture the more rigid regions of membrane proteins, while the most dynamic regions are essentially invisible. Nonetheless, dynamic regions can be detected using experiments in which polarization transfer takes place via J-coupling interactions. Here, we review our recent efforts to develop single and dual acquisition pulse sequences with either 1H or 13C detection that utilize both DC and J-coupling mediated transfer to detect both rigid and mobile regions of membrane proteins in native-like lipid environments. We show the application of these new methods for studying the conformational equilibrium of a single-pass membrane protein, phospholamban, which regulates the calcium transport across the sarcoplasmic reticulum (SR) membrane by interacting with the SR Ca2+-ATPase. We anticipate that these methods will be ideal to portray the complex dynamics of membrane proteins in their native environments.
Collapse
Affiliation(s)
- 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
|
4
|
Supramolecular Organization of Apolipoprotein-A-I-Derived Peptides within Disc-like Arrangements. Biophys J 2018; 115:467-477. [PMID: 30054032 DOI: 10.1016/j.bpj.2018.06.026] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 06/18/2018] [Accepted: 06/20/2018] [Indexed: 01/05/2023] Open
Abstract
Apolipoprotein A-I is the major protein component of high-density lipoproteins and fulfils important functions in lipid metabolism. Its structure consists of a chain of tandem domains of amphipathic helices. Using this protein as a template membrane scaffolding protein, class A amphipathic helical peptides were designed to support the amphipathic helix theory and later as therapeutic tools in biomedicine. Here, we investigated the lipid interactions of two apolipoprotein-A-I-derived class A amphipathic peptides, 14A (Ac-DYLKA FYDKL KEAF-NH2) and 18A (Ac-DWLKA FYDKV AEKLK EAF- NH2), including the disc-like supramolecular structures they form with phospholipids. Thus, the topologies of 14A and 18A in phospholipid bilayers have been determined by oriented solid-state NMR spectroscopy. Whereas at a peptide-to-lipid ratio of 2 mol% the peptides align parallel to the bilayer surface, at 7.5 mol% disc-like structures are formed that spontaneously orient in the magnetic field of the NMR spectrometer. From a comprehensive data set of four 15N- or 2H-labeled positions of 14A, a tilt angle, which deviates from perfectly in-planar by 14°, and a model for the peptidic rim structure have been obtained. The tilt and helical pitch angles are well suited to cover the hydrophobic chain region of the bilayer when two peptide helices form a head-to-tail dimer. Thus, the detailed topology found in this work agrees with the peptides forming the rim of nanodiscs in a double belt arrangement.
Collapse
|
5
|
Gopinath T, Nelson SED, Veglia G. 1H-detected MAS solid-state NMR experiments enable the simultaneous mapping of rigid and dynamic domains of membrane proteins. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2017; 285:101-107. [PMID: 29173803 PMCID: PMC5764182 DOI: 10.1016/j.jmr.2017.09.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 08/30/2017] [Accepted: 09/04/2017] [Indexed: 05/05/2023]
Abstract
Magic angle spinning (MAS) solid-state NMR (ssNMR) spectroscopy is emerging as a unique method for the atomic resolution structure determination of native membrane proteins in lipid bilayers. Although 13C-detected ssNMR experiments continue to play a major role, recent technological developments have made it possible to carry out 1H-detected experiments, boosting both sensitivity and resolution. Here, we describe a new set of 1H-detected hybrid pulse sequences that combine through-bond and through-space correlation elements into single experiments, enabling the simultaneous detection of rigid and dynamic domains of membrane proteins. As proof-of-principle, we applied these new pulse sequences to the membrane protein phospholamban (PLN) reconstituted in lipid bilayers under moderate MAS conditions. The cross-polarization (CP) based elements enabled the detection of the relatively immobile residues of PLN in the transmembrane domain using through-space correlations; whereas the most dynamic region, which is in equilibrium between folded and unfolded states, was mapped by through-bond INEPT-based elements. These new 1H-detected experiments will enable one to detect not only the most populated (ground) states of biomacromolecules, but also sparsely populated high-energy (excited) states for a complete characterization of protein free energy landscapes.
Collapse
Affiliation(s)
- T Gopinath
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, United States
| | - Sarah E D Nelson
- 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
|
6
|
Gopinath T, Nelson SED, Soller KJ, Veglia G. Probing the Conformationally Excited States of Membrane Proteins via 1H-Detected MAS Solid-State NMR Spectroscopy. J Phys Chem B 2017; 121:4456-4465. [DOI: 10.1021/acs.jpcb.7b03268] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- T. Gopinath
- Department of Chemistry and ‡Department of Biochemistry, Molecular Biology, and
Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Sarah E. D. Nelson
- Department of Chemistry and ‡Department of Biochemistry, Molecular Biology, and
Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Kailey J. Soller
- Department of Chemistry and ‡Department of Biochemistry, Molecular Biology, and
Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Gianluigi Veglia
- Department of Chemistry and ‡Department of Biochemistry, Molecular Biology, and
Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, United States
| |
Collapse
|
7
|
Vivekanandan S, Ahuja S, Im SC, Waskell L, Ramamoorthy A. ¹H, ¹³C and ¹⁵N resonance assignments for the full-length mammalian cytochrome b₅ in a membrane environment. BIOMOLECULAR NMR ASSIGNMENTS 2014; 8:409-13. [PMID: 24105099 PMCID: PMC3981966 DOI: 10.1007/s12104-013-9528-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 09/28/2013] [Indexed: 05/12/2023]
Abstract
Microsomal cytochrome b5 plays a key role in the oxidation of a variety of exogenous and endogenous compounds, including drugs, fatty acids, cholesterol and steroid hormones. To better understand its functional properties in a membrane mimic environment, we carried out high-resolution solution NMR studies. Here we report resonance assignments for full-length rabbit cytochrome b5 embedded in dodecylphosphocholine micelles.
Collapse
Affiliation(s)
| | - Shivani Ahuja
- Department of Chemistry and Biophysics, University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Sang-Choul Im
- Department of Anesthesiology, University of Michigan, and VA Medical Center, Ann Arbor, MI 48105, USA
| | - Lucy Waskell
- Department of Anesthesiology, University of Michigan, and VA Medical Center, Ann Arbor, MI 48105, USA
| | - Ayyalusamy Ramamoorthy
- Department of Chemistry and Biophysics, University of Michigan, Ann Arbor, MI 48109-1055, USA
- To whom the correspondence should be addressed: Ayyalusamy Ramamoorthy, Department of Chemistry and Biophysics, University of Michigan, Ann Arbor, Michigan 48109-1055, USA, Tel.: (734) 647-6572; Fax: (734) 764-3323;
| |
Collapse
|
8
|
Kandel SE, Lampe JN. Role of protein-protein interactions in cytochrome P450-mediated drug metabolism and toxicity. Chem Res Toxicol 2014; 27:1474-86. [PMID: 25133307 PMCID: PMC4164225 DOI: 10.1021/tx500203s] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
![]()
Through their unique oxidative chemistry,
cytochrome P450 monooxygenases
(CYPs) catalyze the elimination of most drugs and toxins from the
human body. Protein–protein interactions play a critical role
in this process. Historically, the study of CYP–protein interactions
has focused on their electron transfer partners and allosteric mediators,
cytochrome P450 reductase and cytochrome b5. However, CYPs can bind
other proteins that also affect CYP function. Some examples include
the progesterone receptor membrane component 1, damage resistance
protein 1, human and bovine serum albumin, and intestinal fatty acid
binding protein, in addition to other CYP isoforms. Furthermore, disruption
of these interactions can lead to altered paths of metabolism and
the production of toxic metabolites. In this review, we summarize
the available evidence for CYP protein–protein interactions
from the literature and offer a discussion of the potential impact
of future studies aimed at characterizing noncanonical protein–protein
interactions with CYP enzymes.
Collapse
Affiliation(s)
- Sylvie E Kandel
- XenoTech, LLC , 16825 West 116th Street, Lenexa, Kansas 66219, United States
| | | |
Collapse
|
9
|
Abstract
Membrane proteins have always presented technical challenges for structural studies because of their requirement for a lipid environment. Multiple approaches exist including X-ray crystallography and electron microscopy that can give significant insights into their structure and function. However, nuclear magnetic resonance (NMR) is unique in that it offers the possibility of determining the structures of unmodified membrane proteins in their native environment of phospholipid bilayers under physiological conditions. Furthermore, NMR enables the characterization of the structure and dynamics of backbone and side chain sites of the proteins alone and in complexes with both small molecules and other biopolymers. The learning curve has been steep for the field as most initial studies were performed under non-native environments using modified proteins until ultimately progress in both techniques and instrumentation led to the possibility of examining unmodified membrane proteins in phospholipid bilayers under physiological conditions. This review aims to provide an overview of the development and application of NMR to membrane proteins. It highlights some of the most significant structural milestones that have been reached by NMR spectroscopy of membrane proteins, especially those accomplished with the proteins in phospholipid bilayer environments where they function.
Collapse
|
10
|
Dynamic interaction between membrane-bound full-length cytochrome P450 and cytochrome b5 observed by solid-state NMR spectroscopy. Sci Rep 2014; 3:2538. [PMID: 23985776 PMCID: PMC3756332 DOI: 10.1038/srep02538] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 08/12/2013] [Indexed: 11/09/2022] Open
Abstract
Microsomal monoxygenase enzymes of the cytochrome-P450 family are found in all biological kingdoms, and play a central role in the breakdown of metabolic as well as xenobiotic, toxic and 70% of the drugs in clinical use. Full-length cytochrome-b5 has been shown to be important for the catalytic activity of cytochrome-P450. Despite the significance in understanding the interactions between these two membrane-associated proteins, only limited high-resolution structural information on the full-length cytochrome-P450 and the cytochromes-b5-P450 complex is available. Here, we report a structural study on a functional ~72-kDa cytochromes-b5-P450 complex embedded in magnetically-aligned bicelles without having to freeze the sample. Functional and solid-state NMR (Nuclear Magnetic Resonance) data reveal interactions between the proteins in fluid lamellar phase bilayers. In addition, our data infer that the backbone structure and geometry of the transmembrane domain of cytochrome-b5 is not significantly altered due to its interaction with cytochrome-P450, whereas the mobility of cytochrome-b5 is considerably reduced.
Collapse
|
11
|
Pandey MK, Vivekanandan S, Yamamoto K, Im S, Waskell L, Ramamoorthy A. Proton-detected 2D radio frequency driven recoupling solid-state NMR studies on micelle-associated cytochrome-b(5). JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2014; 242:169-79. [PMID: 24657390 PMCID: PMC4020179 DOI: 10.1016/j.jmr.2014.02.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 02/06/2014] [Accepted: 02/10/2014] [Indexed: 05/08/2023]
Abstract
Solid-state NMR spectroscopy is increasingly used in the high-resolution structural studies of membrane-associated proteins and peptides. Most such studies necessitate isotopically labeled ((13)C, (15)N and (2)H) proteins/peptides, which is a limiting factor for some of the exciting membrane-bound proteins and aggregating peptides. In this study, we report the use of a proton-based slow magic angle spinning (MAS) solid-state NMR experiment that exploits the unaveraged (1)H-(1)H dipolar couplings from a membrane-bound protein. We have shown that the difference in the buildup rates of cross-peak intensities against the mixing time - obtained from 2D (1)H-(1)H radio frequency-driven recoupling (RFDR) and nuclear Overhauser effect spectroscopy (NOESY) experiments on a 16.7-kDa micelle-associated full-length rabbit cytochrome-b5 (cytb5) - can provide insights into protein dynamics and could be useful to measure (1)H-(1)H dipolar couplings. The experimental buildup curves compare well with theoretical simulations and are used to extract relaxation parameters. Our results show that due to fast exchange of amide protons with water in the soluble heme-containing domain of cyb5, coherent (1)H-(1)H dipolar interactions are averaged out for these protons while alpha and side chain protons show residual dipolar couplings that can be obtained from (1)H-(1)H RFDR experiments. The appearance of resonances with distinct chemical shift values in (1)H-(1)H RFDR spectra enabled the identification of residues (mostly from the transmembrane region) of cytb5 that interact with micelles.
Collapse
Affiliation(s)
- Manoj Kumar Pandey
- Biophysics and Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, United States
| | - Subramanian Vivekanandan
- Biophysics and Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, United States
| | - Kazutoshi Yamamoto
- Biophysics and Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, United States
| | - Sangchoul Im
- Department of Anesthesiology, University of Michigan, VA Medical Center, Ann Arbor, MI 48105, United States
| | - Lucy Waskell
- Department of Anesthesiology, University of Michigan, VA Medical Center, Ann Arbor, MI 48105, United States
| | - Ayyalusamy Ramamoorthy
- Biophysics and Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, United States.
| |
Collapse
|
12
|
Ragona L, Pagano K, Tomaselli S, Favretto F, Ceccon A, Zanzoni S, D'Onofrio M, Assfalg M, Molinari H. The role of dynamics in modulating ligand exchange in intracellular lipid binding proteins. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2014; 1844:1268-78. [PMID: 24768771 DOI: 10.1016/j.bbapap.2014.04.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 04/14/2014] [Accepted: 04/16/2014] [Indexed: 11/29/2022]
Abstract
Lipids are essential for many biological processes and crucial in the pathogenesis of several diseases. Intracellular lipid-binding proteins (iLBPs) provide mobile hydrophobic binding sites that allow hydrophobic or amphipathic lipid molecules to penetrate into and across aqueous layers. Thus iLBPs mediate the lipid transport within the cell and participate to a spectrum of tissue-specific pathways involved in lipid homeostasis. Structural studies have shown that iLBPs' binding sites are inaccessible from the bulk, implying that substrate binding should involve a conformational change able to produce a ligand entry portal. Many studies have been reported in the last two decades on iLBPs indicating that their dynamics play a pivotal role in regulating ligand binding and targeted release. The ensemble of reported data has not been reviewed until today. This review is thus intended to summarize and possibly generalize the results up to now described, providing a picture which could help to identify the missing notions necessary to improve our understanding of the role of dynamics in iLBPs' molecular recognition. Such notions would clarify the chemistry of lipid binding to iLBPs and set the basis for the development of new drugs.
Collapse
Affiliation(s)
- Laura Ragona
- Laboratorio NMR, Istituto per lo Studio delle Macromolecole (ISMAC), CNR, Via Bassini 15, 20133 Milano, Italy
| | - Katiuscia Pagano
- Laboratorio NMR, Istituto per lo Studio delle Macromolecole (ISMAC), CNR, Via Bassini 15, 20133 Milano, Italy
| | - Simona Tomaselli
- Laboratorio NMR, Istituto per lo Studio delle Macromolecole (ISMAC), CNR, Via Bassini 15, 20133 Milano, Italy
| | - Filippo Favretto
- Dipartimento di Biotecnologie, Università degli Studi di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Alberto Ceccon
- Dipartimento di Biotecnologie, Università degli Studi di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Serena Zanzoni
- Dipartimento di Biotecnologie, Università degli Studi di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Mariapina D'Onofrio
- Dipartimento di Biotecnologie, Università degli Studi di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Michael Assfalg
- Dipartimento di Biotecnologie, Università degli Studi di Verona, Strada Le Grazie 15, 37134 Verona, Italy
| | - Henriette Molinari
- Laboratorio NMR, Istituto per lo Studio delle Macromolecole (ISMAC), CNR, Via Bassini 15, 20133 Milano, Italy.
| |
Collapse
|
13
|
Probing the transmembrane structure and topology of microsomal cytochrome-p450 by solid-state NMR on temperature-resistant bicelles. Sci Rep 2014; 3:2556. [PMID: 23989972 PMCID: PMC3757361 DOI: 10.1038/srep02556] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Accepted: 08/15/2013] [Indexed: 01/03/2023] Open
Abstract
Though the importance of high-resolution structure and dynamics of membrane proteins has been well recognized, optimizing sample conditions to retain the native-like folding and function of membrane proteins for Nuclear Magnetic Resonance (NMR) or X-ray measurements has been a major challenge. While bicelles have been shown to stabilize the function of membrane proteins and are increasingly utilized as model membranes, the loss of their magnetic-alignment at low temperatures makes them unsuitable to study heat-sensitive membrane proteins like cytochrome-P450 and protein-protein complexes. In this study, we report temperature resistant bicelles that can magnetically-align for a broad range of temperatures and demonstrate their advantages in the structural studies of full-length microsomal cytochrome-P450 and cytochrome-b5 by solid-state NMR spectroscopy. Our results reveal that the N-terminal region of rabbit cytochromeP4502B4, that is usually cleaved off to obtain crystal structures, is helical and has a transmembrane orientation with ~17° tilt from the lipid bilayer normal.
Collapse
|
14
|
Yamamoto K, Caporini MA, Im S, Waskell L, Ramamoorthy A. Shortening spin-lattice relaxation using a copper-chelated lipid at low-temperatures - A magic angle spinning solid-state NMR study on a membrane-bound protein. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2013; 237:175-181. [PMID: 24246881 PMCID: PMC3868731 DOI: 10.1016/j.jmr.2013.10.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 10/19/2013] [Accepted: 10/24/2013] [Indexed: 05/21/2023]
Abstract
Inherent low sensitivity of NMR spectroscopy has been a major disadvantage, especially to study biomolecules like membrane proteins. Recent studies have successfully demonstrated the advantages of performing solid-state NMR experiments at very low and ultralow temperatures to enhance the sensitivity. However, the long spin-lattice relaxation time, T1, at very low temperatures is a major limitation. To overcome this difficulty, we demonstrate the use of a copper-chelated lipid for magic angle spinning solid-state NMR measurements on cytochrome-b5 reconstituted in multilamellar vesicles. Our results on multilamellar vesicles containing as small as 0.5mol% of a copper-chelated lipid can significantly shorten T1 of protons, which can be used to considerably reduce the data collection time or to enhance the signal-to-noise ratio. We also monitored the effect of slow cooling on the resolution and sensitivity of (13)C and (15)N signals from the protein and (13)C signals from lipids.
Collapse
Affiliation(s)
- Kazutoshi Yamamoto
- Biophysics and Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, United States
| | - Marc A Caporini
- Bruker BioSpin Corporation, 15 Fortune Drive, Billerica, MA 01821, United States
| | - Sangchoul Im
- Department of Anesthesiology, University of Michigan, VA Medical Center, Ann Arbor, MI, United States
| | - Lucy Waskell
- Department of Anesthesiology, University of Michigan, VA Medical Center, Ann Arbor, MI, United States
| | - Ayyalusamy Ramamoorthy
- Biophysics and Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, United States.
| |
Collapse
|
15
|
Nowacka A, Bongartz NA, Ollila OHS, Nylander T, Topgaard D. Signal intensities in ¹H-¹³C CP and INEPT MAS NMR of liquid crystals. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2013; 230:165-175. [PMID: 23542743 DOI: 10.1016/j.jmr.2013.02.016] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2012] [Revised: 02/21/2013] [Accepted: 02/27/2013] [Indexed: 06/02/2023]
Abstract
Spectral editing with CP and INEPT in (13)C MAS NMR enables identification of rigid and mobile molecular segments in concentrated assemblies of surfactants, lipids, and/or proteins. In order to get stricter definitions of the terms "rigid" and "mobile", as well as resolving some ambiguities in the interpretation of CP and INEPT data, we have developed a theoretical model for calculating the CP and INEPT intensities as a function of rotational correlation time τc and C-H bond order parameter SCH, taking the effects of MAS into account. According to the model, the range of τc can at typical experimental settings (5kHz MAS, 1ms ramped CP at 80-100kHz B1 fields) be divided into four regimes: fast (τc<1ns), fast-intermediate (τc≈0.1μs), intermediate (τc≈1μs), and slow (τc>0.1ms). In the fast regime, the CP and INEPT intensities are independent of τc, but strongly dependent on |SCH|, with a cross-over from dominating INEPT to dominating CP at |SCH|>0.1. In the intermediate regime, neither CP nor INEPT yield signal on account of fast T1ρ and T2 relaxation. In both the fast-intermediate and slow regimes, there is exclusively CP signal. The theoretical predictions are tested by experiments on the glass-forming surfactant n-octyl-β-d-maltoside, for which τc can be varied continuously in the nano- to millisecond range by changing the temperature and the hydration level. The atomistic details of the surfactant dynamics are investigated with MD simulations. Based on the theoretical model, we propose a procedure for calculating CP and INEPT intensities directly from MD simulation trajectories. While MD shows that there is a continuous gradient of τc from the surfactant polar headgroup towards the methyl group at the end of the hydrocarbon chain, analysis of the experimental CP and INEPT data indicates that this gradient gets steeper with decreasing temperature and hydration level, eventually spanning four orders of magnitude at completely dry conditions.
Collapse
Affiliation(s)
- A Nowacka
- Physical Chemistry, Lund University, P.O. Box 124, SE-22100 Lund, Sweden
| | | | | | | | | |
Collapse
|
16
|
Dürr UH, Soong R, Ramamoorthy A. When detergent meets bilayer: birth and coming of age of lipid bicelles. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2013; 69:1-22. [PMID: 23465641 PMCID: PMC3741677 DOI: 10.1016/j.pnmrs.2013.01.001] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Accepted: 08/30/2012] [Indexed: 05/12/2023]
|
17
|
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
|
18
|
Li S, Su Y, Hong M. Intramolecular 1H-13C distance measurement in uniformly 13C, 15N labeled peptides by solid-state NMR. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2012; 45-46:51-58. [PMID: 22749432 PMCID: PMC3414644 DOI: 10.1016/j.ssnmr.2012.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Revised: 04/29/2012] [Accepted: 06/05/2012] [Indexed: 06/01/2023]
Abstract
A (1)H-(13)C frequency-selective REDOR (FS-REDOR) experiment is developed for measuring intramolecular (1)H-(13)C distances in uniformly (13)C, (15)N-labeled molecules. Theory and simulations show that the experiment removes the interfering homonuclear (1)H-(1)H, (13)C-(13)C and heteronuclear (1)H-(15)N, (13)C-(15)N dipolar interactions while retaining the desired heteronuclear (1)H-(13)C dipolar interaction. Our results indicate that this technique, combined with the numerical fitting, can be used to measure a (1)H-(13)C distance up to 5Å. We also demonstrate that the measured intramolecular (1)H-(13)C distances are useful to determine dihedral angles in proteins.
Collapse
Affiliation(s)
- Shenhui Li
- Wuhan Institute of Physics and Mathematics, the Chinese Academy of Sciences, Wuhan 430071, China
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
| | - Yongchao Su
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
| | - Mei Hong
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
| |
Collapse
|
19
|
Paramasivam S, Suiter CL, Hou G, Sun S, Palmer M, Hoch JC, Rovnyak D, Polenova T. Enhanced sensitivity by nonuniform sampling enables multidimensional MAS NMR spectroscopy of protein assemblies. J Phys Chem B 2012; 116:7416-27. [PMID: 22667827 DOI: 10.1021/jp3032786] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
We report dramatic sensitivity enhancements in multidimensional MAS NMR spectra by the use of nonuniform sampling (NUS) and introduce maximum entropy interpolation (MINT) processing that assures the linearity between the time and frequency domains of the NUS acquired data sets. A systematic analysis of sensitivity and resolution in 2D and 3D NUS spectra reveals that with NUS, at least 1.5- to 2-fold sensitivity enhancement can be attained in each indirect dimension without compromising the spectral resolution. These enhancements are similar to or higher than those attained by the newest-generation commercial cryogenic probes. We explore the benefits of this NUS/MaxEnt approach in proteins and protein assemblies using 1-73-(U-(13)C,(15)N)/74-108-(U-(15)N) Escherichia coli thioredoxin reassembly. We demonstrate that in thioredoxin reassembly, NUS permits acquisition of high-quality 3D-NCACX spectra, which are inaccessible with conventional sampling due to prohibitively long experiment times. Of critical importance, issues that hinder NUS-based SNR enhancement in 3D-NMR of liquids are mitigated in the study of solid samples in which theoretical enhancements on the order of 3-4 fold are accessible by compounding the NUS-based SNR enhancement of each indirect dimension. NUS/MINT is anticipated to be widely applicable and advantageous for multidimensional heteronuclear MAS NMR spectroscopy of proteins, protein assemblies, and other biological systems.
Collapse
Affiliation(s)
- Sivakumar Paramasivam
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Bechinger B, Salnikov ES. The membrane interactions of antimicrobial peptides revealed by solid-state NMR spectroscopy. Chem Phys Lipids 2012; 165:282-301. [DOI: 10.1016/j.chemphyslip.2012.01.009] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Revised: 01/25/2012] [Accepted: 01/27/2012] [Indexed: 01/29/2023]
|
21
|
Ohgo K, Niemczura WP, Seacat BC, Wise SG, Weiss AS, Kumashiro KK. Resolving nitrogen-15 and proton chemical shifts for mobile segments of elastin with two-dimensional NMR spectroscopy. J Biol Chem 2012; 287:18201-9. [PMID: 22474297 DOI: 10.1074/jbc.m111.285163] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In this study, one- and two-dimensional NMR experiments are applied to uniformly (15)N-enriched synthetic elastin, a recombinant human tropoelastin that has been cross-linked to form an elastic hydrogel. Hydrated elastin is characterized by large segments that undergo "liquid-like" motions that limit the efficiency of cross-polarization. The refocused insensitive nuclei enhanced by polarization transfer experiment is used to target these extensive, mobile regions of this protein. Numerous peaks are detected in the backbone amide region of the protein, and their chemical shifts indicate the completely unstructured, "random coil" model for elastin is unlikely. Instead, more evidence is gathered that supports a characteristic ensemble of conformations in this rubber-like protein.
Collapse
Affiliation(s)
- Kosuke Ohgo
- Department of Chemistry, University of Hawaii, Honolulu, Hawaii 96822, USA
| | | | | | | | | | | |
Collapse
|
22
|
Lin EC, Opella SJ. 1H assisted 13C/15N heteronuclear correlation spectroscopy in oriented sample solid-state NMR of single crystal and magnetically aligned samples. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2011; 211:37-44. [PMID: 21543244 PMCID: PMC3236683 DOI: 10.1016/j.jmr.2011.03.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2011] [Revised: 03/23/2011] [Accepted: 03/29/2011] [Indexed: 05/30/2023]
Abstract
(1)H-irradiation under mismatched Hartmann-Hahn conditions provides an alternative mechanism for carrying out (15)N/(13)C transfers in triple-resonance heteronuclear correlation spectroscopy (HETCOR) on stationary samples of single crystals and aligned samples of biopolymers, which improve the efficiency especially when the direct (15)N-(13)C dipolar couplings are small. In many cases, the sensitivity is improved by taking advantage of the (13)C(α) labeled sites in peptides and proteins with (13)C detection. The similarities between experimental and simulated spectra demonstrate the validity of the recoupling mechanism and identify the potential for applying these experiments to virus particles or membrane proteins in phospholipid bilayers; however, further development is needed in order to derive quantitative distance and angular constraints from these measurements.
Collapse
Affiliation(s)
| | - Stanley J. Opella
- Corresponding Author: Stanley J. Opella, , phone 858 822-4820, FAX 858 822-4821
| |
Collapse
|
23
|
Bechinger B, Resende JM, Aisenbrey C. The structural and topological analysis of membrane-associated polypeptides by oriented solid-state NMR spectroscopy: established concepts and novel developments. Biophys Chem 2010; 153:115-25. [PMID: 21145159 DOI: 10.1016/j.bpc.2010.11.002] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Revised: 11/05/2010] [Accepted: 11/05/2010] [Indexed: 10/18/2022]
Abstract
Solid-state NMR spectroscopy is a powerful technique for the investigation of membrane-associated peptides and proteins as well as their interactions with lipids, and a variety of conceptually different approaches have been developed for their study. The technique is unique in allowing for the high-resolution investigation of liquid disordered lipid bilayers representing well the characteristics of natural membranes. Whereas magic angle solid-state NMR spectroscopy follows approaches that are related to those developed for solution NMR spectroscopy the use of static uniaxially oriented samples results in angular constraints which also provide information for the detailed analysis of polypeptide structures. This review introduces this latter concept theoretically and provides a number of examples. Furthermore, ongoing developments combining solid-state NMR spectroscopy with information from solution NMR spectroscopy and molecular modelling as well as exploratory studies using dynamic nuclear polarization solid-state NMR will be presented.
Collapse
Affiliation(s)
- Burkhard Bechinger
- Université de Strasbourg/CNRS, UMR7177, Institut de Chimie, 4 Rue Blaise Pascal, 67070 Strasbourg, France.
| | | | | |
Collapse
|