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Denisov IG, Sligar SG. Nanodiscs for the study of membrane proteins. Curr Opin Struct Biol 2024; 87:102844. [PMID: 38795563 PMCID: PMC11283964 DOI: 10.1016/j.sbi.2024.102844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 04/25/2024] [Accepted: 05/03/2024] [Indexed: 05/28/2024]
Abstract
Nanodiscs represent a versatile tool for studies of membrane proteins and protein-membrane interactions under native-like conditions. Multiple variations of the Nanodisc platform, as well as new experimental methods, have been recently developed to understand various aspects of structure, dynamics and functional properties of systems involved in signaling, transport, blood coagulation and many other critically important processes. In this mini-review, we focus on some of these exciting recent developments that utilize the Nanodisc platform.
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Affiliation(s)
- Ilia G Denisov
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, USA
| | - Stephen G Sligar
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, USA.
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2
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Krishnarjuna B, Sharma G, Hiiuk VM, Struppe J, Nagorny P, Ivanova MI, Ramamoorthy A. Nanodisc Reconstitution and Characterization of Amyloid-β Precursor Protein C99. Anal Chem 2024; 96:9362-9369. [PMID: 38826107 DOI: 10.1021/acs.analchem.3c05727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
Amyloid precursor protein (APP) plays a pivotal role in the pathology of Alzheimer's disease (AD). Since the fragmentation of the membrane-bound APP that results in the production of amyloid-β peptides is the starting point for amyloid toxicity in AD, it is important to investigate the structure and dynamics of APP in a near-native lipid-bilayer environment. However, the reconstitution of APP into a stable and suitable membrane-mimicking lipid environment is a challenging task. In this study, the 99-residue C-terminal domain of APP is successfully reconstituted into polymer nanodiscs and characterized using size-exclusion chromatography, mass spectrometry, solution NMR, and magic-angle spinning solid-state NMR. In addition, the feasibility of using lipid-solubilizing polymers for isolating and characterizing APP in the native Escherichia. coli membrane environment is demonstrated.
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Affiliation(s)
- Bankala Krishnarjuna
- Biophysics Program, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Chemistry, Biomedical Engineering, Macromolecular Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Gaurav Sharma
- Biophysics Program, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Chemistry, Biomedical Engineering, Macromolecular Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Volodymyr M Hiiuk
- Biophysics Program, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Jochem Struppe
- Bruker Biospin Corporation, 15 Fortune Drive, Billerica, Massachusetts 01821, United States
| | - Pavel Nagorny
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Magdalena I Ivanova
- Biophysics Program, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Neurology, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Ayyalusamy Ramamoorthy
- Biophysics Program, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Chemistry, Biomedical Engineering, Macromolecular Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, United States
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, Florida 32310, United States
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3
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Dong Y, Li M, Kang L, Wang W, Li Z, Wang Y, Wu Z, Zhu C, Zhu L, Zheng X, Qian D, Dai H, Wu B, Zhao H, Wang J. A new preparation method of covalent annular nanodiscs based on MTGase. Arch Biochem Biophys 2024; 756:109997. [PMID: 38621443 DOI: 10.1016/j.abb.2024.109997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 03/11/2024] [Accepted: 04/12/2024] [Indexed: 04/17/2024]
Abstract
The preservation of the native conformation and functionality of membrane proteins has posed considerable challenges. While detergents and liposome reconstitution have been traditional approaches, nanodiscs (NDs) offer a promising solution by embedding membrane proteins in phospholipids encircled by an amphipathic helical protein MSP belt. Nevertheless, a drawback of commonly used NDs is their limited homogeneity and stability. In this study, we present a novel approach to construct covalent annular nanodiscs (cNDs) by leveraging microbial transglutaminase (MTGase) to catalyze isopeptide bond formation between the side chains of terminal amino acids, specifically Lysine (K) and Glutamine (Q). This methodology significantly enhances the homogeneity and stability of NDs. Characterization of cNDs and the assembly of membrane proteins within them validate the successful reconstitution of membrane proteins with improved homogeneity and stability. Our findings suggest that cNDs represent a more suitable tool for investigating interactions between membrane proteins and lipids, as well as for analyzing membrane protein structures.
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Affiliation(s)
- Yingkui Dong
- Institute of Physical Science and Information Technology, Anhui University, Hefei, Anhui, 230039, China; High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, China
| | - Ming Li
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, China; University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Li Kang
- Institute of Physical Science and Information Technology, Anhui University, Hefei, Anhui, 230039, China; High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, China
| | - Wanxue Wang
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, China; School of Basic Medical Sciences, Anhui Medical University, Hefei, Anhui, 230032, China
| | - Zehua Li
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, China; University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Yizhuo Wang
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, China; University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Ziwei Wu
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, China; University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Chenchen Zhu
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, China; University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Lei Zhu
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, China
| | - Xinwei Zheng
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, China
| | - Dongming Qian
- Hefei China Science Longwood Biological Technology Co., Ltd. Hefei, Anhui, 230088, China
| | - Han Dai
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, China; Hefei China Science Longwood Biological Technology Co., Ltd. Hefei, Anhui, 230088, China
| | - Bo Wu
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, China.
| | - Hongxin Zhao
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, China; Hefei China Science Longwood Biological Technology Co., Ltd. Hefei, Anhui, 230088, China.
| | - Junfeng Wang
- Institute of Physical Science and Information Technology, Anhui University, Hefei, Anhui, 230039, China; High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, China; University of Science and Technology of China, Hefei, Anhui, 230026, China.
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4
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Woubshete M, Cioccolo S, Byrne B. Advances in Membrane Mimetic Systems for Manipulation and Analysis of Membrane Proteins: Detergents, Polymers, Lipids and Scaffolds. Chempluschem 2024; 89:e202300678. [PMID: 38315323 DOI: 10.1002/cplu.202300678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 01/31/2024] [Accepted: 02/05/2024] [Indexed: 02/07/2024]
Abstract
Extracting membrane proteins from the hydrophobic environment of the biological membrane, in a physiologically relevant and stable state, suitable for downstream analysis remains a challenge. The traditional route to membrane protein extraction has been to use detergents and the last 15 years or so have seen a veritable explosion in the development of novel detergents with improved properties, making them more suitable for individual proteins and specific applications. There have also been significant advances in the development of encapsulation of membrane proteins in lipid based nanodiscs, either directly from the native membrane using polymers allowing effective capture of the protein and protein-associated membrane lipids, or via reconstitution of detergent extracted and purified protein into nanodiscs of defined lipid composition. All of these advances have been successfully applied to the study of membrane proteins via a range of techniques and there have been some spectacular membrane protein structures solved. In addition, the first detailed structural and biophysical analyses of membrane proteins retained within a biological membrane have been reported. Here we summarise and review the recent advances with respect to these new agents and systems for membrane protein extraction, reconstitution and analysis.
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Affiliation(s)
- Menebere Woubshete
- Department of Life Sciences, Imperial College London, South Kensington, London, SW7 2AZ, United Kingdom
| | - Sara Cioccolo
- Department of Life Sciences, Imperial College London, South Kensington, London, SW7 2AZ, United Kingdom
- Department of Chemistry, Imperial College London, White City, London, W12 0BZ, United Kingdom
| | - Bernadette Byrne
- Department of Life Sciences, Imperial College London, South Kensington, London, SW7 2AZ, United Kingdom
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5
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Krishnarjuna B, Sharma G, Hiiuk VM, Struppe J, Nagorny P, Ivanova MI, Ramamoorthy A. Nanodisc reconstitution and characterization of amyloid-β precursor protein C99. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.21.590446. [PMID: 38659865 PMCID: PMC11042261 DOI: 10.1101/2024.04.21.590446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Amyloid precursor protein (APP) plays a pivotal role in the pathology of Alzheimer's disease. Since the fragmentation of the membrane-bound APP that results in the production of amyloid-beta peptides is the starting point for amyloid toxicity in AD, it is important to investigate the structure and dynamics of APP in a near-native lipid-bilayer environment. However, the reconstitution of APP into a stable/suitable membrane-mimicking lipid environment is a challenging task. In this study, the 99-residue C-terminal domain of APP is successfully reconstituted into polymer nanodiscs and characterized using size-exclusion chromatography, mass spectrometry, solution NMR, and magic-angle spinning solid-state NMR. In addition, the feasibility of using lipid-solubilizing polymers for isolating and characterizing APP in native E. coli membrane environment is demonstrated.
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Affiliation(s)
- Bankala Krishnarjuna
- Biophysics Program, University of Michigan, Ann Arbor, MI 48109, United States
- Department of Chemistry, Biomedical Engineering, Macromolecular Science and Engineering, University of Michigan, Ann Arbor, MI 48109, United States
| | - Gaurav Sharma
- Biophysics Program, University of Michigan, Ann Arbor, MI 48109, United States
- Department of Chemistry, Biomedical Engineering, Macromolecular Science and Engineering, University of Michigan, Ann Arbor, MI 48109, United States
| | - Volodymyr M Hiiuk
- Biophysics Program, University of Michigan, Ann Arbor, MI 48109, United States
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Jochem Struppe
- Bruker Biospin Corporation, 15 Fortune Drive, Billerica, Massachusetts 01821, United States
| | - Pavel Nagorny
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Magdalena I Ivanova
- Biophysics Program, University of Michigan, Ann Arbor, MI 48109, United States
- Department of Neurology, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Ayyalusamy Ramamoorthy
- Biophysics Program, University of Michigan, Ann Arbor, MI 48109, United States
- Department of Chemistry, Biomedical Engineering, Macromolecular Science and Engineering, University of Michigan, Ann Arbor, MI 48109, United States
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, FL 32310, United States
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, United States
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6
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Fu R, Ramamoorthy A. 17O Solid-State NMR Spectroscopy of Lipid Membranes. J Phys Chem B 2024; 128:3527-3537. [PMID: 38568422 DOI: 10.1021/acs.jpcb.4c01016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2024]
Abstract
Despite the limitations posed by poor sensitivity, studies have reported the unique advantages of 17O based NMR spectroscopy to study systems existing in liquid, solid, or semisolid states. 17O NMR studies have exploited the remarkable sensitivity of quadrupole coupling and chemical shift anisotropy tensors to the local environment in the characterization of a variety of intra- and intermolecular interactions and motion. Recent studies have considerably expanded the use of 17O NMR to study dynamic intermolecular interactions associated with some of the challenging biological systems under magic angle spinning (MAS) and aligned conditions. The very fast relaxing nature of 17O has been well utilized in cellular and in vivo MRS (magnetic resonance spectroscopy) and MRI (magnetic resonance imaging) applications. The main focus of this Review is to highlight the new developments in the biological solids with a detailed discussion for a few selected examples including membrane proteins and nanodiscs. In addition to the unique benefits and limitations, the remaining challenges to overcome, and the impacts of higher magnetic fields and sensitivity enhancement techniques are discussed.
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Affiliation(s)
- Riqiang Fu
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, United States
| | - Ayyalusamy Ramamoorthy
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, United States
- Department of Chemical and Biomedical Engineering, Institute of Molecular Biophysics, Florida State University, Tallahassee, Florida 32310, United States
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7
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Kaluzhskiy L, Yablokov E, Gnedenko O, Burkatovskii D, Maslov I, Bogorodskiy A, Ershov P, Tsybruk T, Zelepuga E, Rutckova T, Kozlovskaya E, Dmitrenok P, Gilep A, Borshchevskiy V, Strushkevich N, Ivanov A. The effect of membrane composition on the interaction between human CYP51 and its flavonoid inhibitor - luteolin 7,3'-disulfate. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2024; 1866:184286. [PMID: 38272204 DOI: 10.1016/j.bbamem.2024.184286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 12/22/2023] [Accepted: 01/16/2024] [Indexed: 01/27/2024]
Abstract
Cytochromes P450 (CYP) are a family of membrane proteins involved in the production of endogenous molecules and the metabolism of xenobiotics. It is well-known that the composition of the membrane can influence the activity and orientation of CYP proteins. However, little is known about how membrane composition affects the ligand binding properties of CYP. In this study, we utilized surface plasmon resonance and fluorescence lifetime analysis to examine the impact of membrane micro-environment composition on the interaction between human microsomal CYP51 (CYP51A1) and its inhibitor, luteolin 7,3'-disulphate (LDS). We observed that membranes containing cholesterol or sphingomyelin exhibited the lowest apparent equilibrium dissociation constant for the CYP51A1-LDS complex. Additionally, the tendency for relation between kinetic parameters of the CYP51A1-LDS complex and membrane viscosity and overall charge was observed. These findings suggest that the specific composition of the membrane, particularly the presence of cholesterol and sphingomyelin, plays a vital role in regulating the interaction between CYP enzymes and their ligands.
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Affiliation(s)
- Leonid Kaluzhskiy
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia.
| | - Evgeniy Yablokov
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia.
| | - Oksana Gnedenko
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia.
| | - Dmitrii Burkatovskii
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia.
| | - Ivan Maslov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia.
| | - Andrey Bogorodskiy
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia
| | - Pavel Ershov
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia
| | - Tatsiana Tsybruk
- Institute of Bioorganic Chemistry NASB, 5 Building 2, V.F. Kuprevich Street, 220141 Minsk, Belarus
| | - Elena Zelepuga
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Science, 159 Prospect 100-letiya Vladivostoka, 690022 Vladivostok, Russia.
| | - Tatyana Rutckova
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Science, 159 Prospect 100-letiya Vladivostoka, 690022 Vladivostok, Russia
| | - Emma Kozlovskaya
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Science, 159 Prospect 100-letiya Vladivostoka, 690022 Vladivostok, Russia
| | - Pavel Dmitrenok
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Science, 159 Prospect 100-letiya Vladivostoka, 690022 Vladivostok, Russia.
| | - Andrei Gilep
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia; Institute of Bioorganic Chemistry NASB, 5 Building 2, V.F. Kuprevich Street, 220141 Minsk, Belarus.
| | - Valentin Borshchevskiy
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia; Joint Institute for Nuclear Research, Dubna 141980, Russia
| | - Natallia Strushkevich
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30, bld. 1, 121205 Moscow, Russia.
| | - Alexis Ivanov
- Institute of Biomedical Chemistry, 10 Building 8, Pogodinskaya Street, 119121 Moscow, Russia.
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Krishnarjuna B, Sharma G, Ravula T, Ramamoorthy A. Factors influencing the detergent-free membrane protein isolation using synthetic nanodisc-forming polymers. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2024; 1866:184240. [PMID: 37866688 DOI: 10.1016/j.bbamem.2023.184240] [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: 05/12/2023] [Revised: 10/08/2023] [Accepted: 10/17/2023] [Indexed: 10/24/2023]
Abstract
The detergent-free isolation of membrane proteins using synthetic polymers is becoming the desired approach for functional and structural studies of membrane proteins. Since the expression levels for many membrane proteins are low and a high yield of functionalized reconstituted membrane proteins is essential for in vitro studies, it is crucial to optimize the experimental conditions for a given polymer to solubilize target membranes/proteins effectively. The factors that affect membrane solubilization and subsequently the isolation of a target membrane protein include polymer concentration, polymer charge, temperature, pH, and concentration of divalent metal ions. Therefore, it is important to have knowledge about the efficacy of different types of polymers in solubilizing cell membranes. In this study, we evaluate the efficacy of inulin-based non-ionic polymers in solubilizing E. coli membranes enriched with rat flavin mononucleotide binding-domain (FBD) of cytochrome-P450-reductase (CPR) and rabbit cytochrome-b5 (Cyt-b5) under various solubilization conditions. Our results show that a 1:1 (w/w) membrane:polymer ratio, low temperature, high pH and sub-millimolar concentration of metal ions favor the solubilization of E. coli membranes enriched with FBD or Cyt-b5. Conversely, the presence of excess divalent metal ions affected the final protein levels in the polymer-solubilized samples. We believe that the results from this study provide knowledge to assess and plan the use of non-ionic polymers in membrane protein studies.
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Affiliation(s)
- Bankala Krishnarjuna
- Biophysics Program, Department of Chemistry, Biomedical Engineering, Macromolecular Science and Engineering, Michigan Neuroscience Institute, The University of Michigan, Ann Arbor, MI 48109, USA
| | - Gaurav Sharma
- Biophysics Program, Department of Chemistry, Biomedical Engineering, Macromolecular Science and Engineering, Michigan Neuroscience Institute, The University of Michigan, Ann Arbor, MI 48109, USA
| | - Thirupathi Ravula
- Biophysics Program, Department of Chemistry, Biomedical Engineering, Macromolecular Science and Engineering, Michigan Neuroscience Institute, The University of Michigan, Ann Arbor, MI 48109, USA
| | - Ayyalusamy Ramamoorthy
- National High Magnetic Field Laboratory, Department of Chemical and Biomedical Engineering, Florida State University, Tallahassee, FL 32310, USA.
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9
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Krishnarjuna B, Sharma G, Im SC, Auchus R, Anantharamaiah GM, Ramamoorthy A. Characterization of nanodisc-forming peptides for membrane protein studies. J Colloid Interface Sci 2024; 653:1402-1414. [PMID: 37801850 PMCID: PMC10864042 DOI: 10.1016/j.jcis.2023.09.162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 09/11/2023] [Accepted: 09/27/2023] [Indexed: 10/08/2023]
Abstract
Lipid-bilayer nanodiscs provide a stable, native-like membrane environment for the functional and structural studies of membrane proteins and other membrane-binding molecules. Peptide-based nanodiscs having unique properties are developed for membrane protein studies and other biological applications. While the self-assembly process rendering the formation of peptide-nanodiscs is attractive, it is important to understand the stability and suitability of these nanodisc systems for membrane protein studies. In this study, we investigated the nanodiscs formation by the anti-inflammatory and tumor-suppressing peptide AEM28. AEM28 is a chimeric peptide containing a cationic-rich heparan sulfate proteoglycan- (HSPG)-binding domain from human apolipoprotein E (hapoE) (141-150) followed by the 18A peptide's amino acid sequence. AEM28-based nanodiscs made with different types of lipids were characterized using various biophysical techniques and compared with the nanodiscs formed using 2F or 4F peptides. Variable temperature dynamic light-scattering and 31P NMR experiments indicated the fusion and size heterogeneity of nanodiscs at high temperatures. The suitability of AEM28 and Ac-18A-NH2- (2F-) based nanodiscs for studying membrane proteins is demonstrated by reconstituting and characterizing a drug-metabolizing enzyme, cytochrome-P450 (CYP450), or the redox complex CYP450-CYP450 reductase. AEM28 and 2F were also tested for their efficacies in solubilizing E. coli membranes to understand the possibility of using them for detergent-free membrane protein isolation. Our experimental results suggest that AEM28 nanodiscs are suitable for studying membrane proteins with a net positive charge, whereas 2F-based nanodiscs are compatible with any membrane proteins and their complexes irrespective of their charge. Furthermore, both peptides solubilized E. coli cell membranes, indicating their use in membrane protein isolation and other applications related to membrane solubilization.
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Affiliation(s)
- Bankala Krishnarjuna
- Biophysics Program, Department of Chemistry, Biomedical Engineering, Macromolecular Science and Engineering, University of Michigan, Arbor, MI 48109, USA
| | - Gaurav Sharma
- Biophysics Program, Department of Chemistry, Biomedical Engineering, Macromolecular Science and Engineering, University of Michigan, Arbor, MI 48109, USA
| | - Sang-Choul Im
- Department of Pharmacology and Internal Medicine, Division of Metabolism, Endocrinology, & Diabetes, University of Michigan, Ann Arbor, MI 48109, USA
| | - Richard Auchus
- Department of Pharmacology and Internal Medicine, Division of Metabolism, Endocrinology, & Diabetes, University of Michigan, Ann Arbor, MI 48109, USA
| | - G M Anantharamaiah
- Department of Medicine, University of Alabama at Birmingham Medical Center, Birmingham, AL 35294, USA
| | - Ayyalusamy Ramamoorthy
- Biophysics Program, Department of Chemistry, Biomedical Engineering, Macromolecular Science and Engineering, University of Michigan, Arbor, MI 48109, USA; National High Magnetic Field Laboratory, Department of Chemical and Biomedical Engineering, Tallahassee, FL 32310, USA.
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10
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Hoang Trinh TK, Catalano C, Guo Y. Fabrication of membrane proteins in the form of native cell membrane nanoparticles using novel membrane active polymers. NANOSCALE ADVANCES 2023; 5:5932-5940. [PMID: 37881706 PMCID: PMC10597567 DOI: 10.1039/d3na00381g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 10/04/2023] [Indexed: 10/27/2023]
Abstract
Membrane proteins are a widespread class of bio-macromolecules responsible for numerous vital biological processes and serve as therapeutic targets for a vast array of contemporary medications. For membrane protein isolation and purification, detergents have historically been used. Despite this, detergents frequently result in protein instability. Consequently, their application was limited. Recent detergent-free approaches have been invented. Among these, styrene-maleic acid lipid particle (SMALP), diisobutylene-maleic acid lipid particle (DIBMALP), and native cell membrane nanoparticle (NCMN) systems are the most prevalent. The NCMN system intends to create a library of membrane-active polymers suitable for high-resolution structure determination of membrane protein. Design, synthesis, characterization, and comparative application evaluations of three novel classes of NCMN polymers, NCMNP13-x, NCMNP21-x, and NCMNP21b-x, are presented in this article. Although each NCMN polymer can solubilize distinct model membrane proteins and retain native lipids in NCMN particles, only the NCMNP21b-x family produces lipid-protein particles with ideal buffer compatibility and high homogeneity suitable for single-particle cryo-EM analysis. NCMNP21b-x polymers that generate high-quality NCMN particles are particularly desirable for membrane protein structural biology.
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Affiliation(s)
- Thi Kim Hoang Trinh
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University Richmond VA 23298 USA
- Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University Richmond VA 23219 USA
| | - Claudio Catalano
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University Richmond VA 23298 USA
- Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University Richmond VA 23219 USA
| | - Youzhong Guo
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University Richmond VA 23298 USA
- Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University Richmond VA 23219 USA
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11
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Janata M, Gupta S, Čadová E, Angelisová P, Krishnarjuna B, Ramamoorthy A, Hořejší V, Raus V. Sulfonated polystyrenes: pH and Mg 2+-insensitive amphiphilic copolymers for detergent-free membrane protein isolation. Eur Polym J 2023; 198:112412. [PMID: 37780808 PMCID: PMC10538444 DOI: 10.1016/j.eurpolymj.2023.112412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/03/2023]
Abstract
Amphiphilic polymers are increasingly applied in the detergent-free isolation and functional studies of membrane proteins. However, the carboxylate group present in the structure of many popular variants, such as styrene-maleic acid (SMA) copolymers, brings limitations in terms of polymer sensitivity to precipitation at acidic pH or in the presence of divalent metal cations. Herein, we addressed this problem by replacing carboxylate with the more acidic sulfonate groups. To this end, we synthesized a library of amphiphilic poly[styrene-co-(sodium 4-styrene sulfonate)] copolymers (termed SSS), differing in their molecular weight and overall polarity. Using model cell membranes (Jurkat), we identified two copolymer compositions (SSS-L30 and SSS-L36) that solubilized membranes to an extent similar to SMA. Interestingly, the density gradient ultracentrifugation/SDS-PAGE/Western blotting analysis of cell lysates revealed a distribution of studied membrane proteins in the gradient fractions that was different than for SMA-solubilized membranes. Importantly, unlike SMA, the SSS copolymers remained soluble at low pH and in the presence of Mg2+ ions. Additionally, the solubilization of DMPC liposomes by the lead materials was studied by turbidimetry, DLS, SEC, and high-resolution NMR, revealing, for SSS-L36, the formation of stable particles (nanodiscs), facilitated by the direct hydrophobic interaction of the copolymer phenyls with lipid acyl chains.
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Affiliation(s)
- Miroslav Janata
- Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovského nám. 2, 162 06 Prague 6, Czech Republic
| | - Sachin Gupta
- Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovského nám. 2, 162 06 Prague 6, Czech Republic
| | - Eva Čadová
- Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovského nám. 2, 162 06 Prague 6, Czech Republic
| | - Pavla Angelisová
- Institute of Molecular Genetics of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague 4, Czech Republic
| | - Bankala Krishnarjuna
- Biophysics Program, Department of Chemistry, Macromolecular Science and Engineering, Biomedical Engineering, Michigan Neuroscience Institute, The University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Ayyalusamy Ramamoorthy
- Biophysics Program, Department of Chemistry, Macromolecular Science and Engineering, Biomedical Engineering, Michigan Neuroscience Institute, The University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Václav Hořejší
- Institute of Molecular Genetics of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague 4, Czech Republic
| | - Vladimír Raus
- Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovského nám. 2, 162 06 Prague 6, Czech Republic
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12
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Pettersen JM, Yang Y, Robinson AS. Advances in nanodisc platforms for membrane protein purification. Trends Biotechnol 2023; 41:1041-1054. [PMID: 36935323 DOI: 10.1016/j.tibtech.2023.02.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 02/07/2023] [Accepted: 02/20/2023] [Indexed: 03/19/2023]
Abstract
Membrane scaffold protein nanodiscs (MSPNDs) are an invaluable tool for improving purified membrane protein (MP) stability and activity compared to traditional micellar methods, thus enabling an increase in high-resolution MP structures, particularly in concert with cryogenic electron microscopy (cryo-EM) approaches. In this review we highlight recent advances and breakthroughs in MSPND methodology and applications. We also introduce and discuss saposin-lipoprotein nanoparticles (salipros) and copolymer nanodiscs which have recently emerged as authentic MSPND alternatives. We compare the advantages and disadvantages of MSPNDs, salipros, and copolymer nanodisc technologies to highlight potential opportunities for using each platform for MP purification and characterization.
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Affiliation(s)
- John M Pettersen
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Yaxin Yang
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Anne S Robinson
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA.
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13
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Denisov IG, Sligar SG. Solvent isotope effects in the catalytic cycle of P450 CYP17A1: Computational modeling of the hydroxylation and lyase reactions. J Inorg Biochem 2023; 243:112202. [PMID: 37004494 PMCID: PMC10128154 DOI: 10.1016/j.jinorgbio.2023.112202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 03/13/2023] [Accepted: 03/26/2023] [Indexed: 03/31/2023]
Abstract
The catalytic cycle of the cytochromes P450 (CYP) requires two electrons from a protein redox partner and two protons from water to generate the main catalytic intermediate, a ferryl-oxo complex with π-cation on the heme porphyrin ring, termed Compound 1. The protonation steps are at least partially rate-limiting, therefore the steady-state rates of P450 catalysis are usually slower in deuterated solvent (D2O) by a factor of 1.5-3. However, in several P450 systems a pronounced inverse kinetic solvent isotope effect (KSIE ∼0.4-0.7) is observed, where the reaction is faster in D2O. This raises an important mechanistic question: Is this inverse solvent isotope effect compatible with Compound 1 catalyzed reactions, or is it indicative of another catalytic intermediate being involved? In this communication we use exhaustive numerical modeling of the P450 steady-state kinetics to demonstrate that a significant inverse KSIE cannot be obtained for a pure Compound 1 driven catalytic cycle of P450. Rather, an alternative, protonation independent, catalytic intermediate needs to be introduced. This result is applicable to the broad spectrum of P450s in nature, but as an example we use the extensively documented inverse isotope effect in the human steroid biosynthetic P450 CYP17A1 where the involvement of a heme peroxo anion intermediate has been characterized. Based on this analysis, we show that the observation of an inverse KSIE can be used as a general mechanistic probe for reaction cycle intermediates in the cytochromes P450.
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Affiliation(s)
- Ilia G Denisov
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, United States of America
| | - Stephen G Sligar
- Department of Biochemistry, University of Illinois, Urbana, IL 61801, United States of America.
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14
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Krishnarjuna B, Marte J, Ravula T, Ramamoorthy A. Enhancing the stability and homogeneity of non-ionic polymer nanodiscs by tuning electrostatic interactions. J Colloid Interface Sci 2023; 634:887-896. [PMID: 36566634 PMCID: PMC10838601 DOI: 10.1016/j.jcis.2022.12.112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 12/14/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022]
Abstract
The nanodisc technology is increasingly used for structural studies on membrane proteins and drug delivery. The development of synthetic polymer nanodiscs and the recent discovery of non-ionic inulin-based polymers have significantly broadened the scope of nanodiscs. While the lipid exchange and size flexibility properties of the self-assembled polymer-based nanodiscs are valuable for various applications, the non-ionic polymer nanodiscs are remarkably unique in that they enable the reconstitution of any protein, protein-protein complexes, or drugs irrespective of their charge. However, the non-ionic nature of the belt could influence the stability and size homogeneity of inulin-based polymer nanodiscs. In this study, we investigate the size stability and homogeneity of nanodiscs formed by non-ionic lipid-solubilizing polymers using different biophysical methods. Polymer nanodiscs containing zwitterionic DMPC and different ratios of DMPC:DMPG lipids were made using anionic SMA-EA or non-ionic pentyl-inulin polymers. Non-ionic polymer nanodiscs made using zwitterionic DMPC lipids produced a very broad elution profile on SEC due to their instability in the column, thus affecting sample monodispersity which was confirmed by DLS experiments that showed multiple peaks. However, the inclusion of anionic DMPG lipids improved the stability as observed from SEC and DLS profiles, which was further confirmed by TEM images. Whereas, anionic SMA-EA-based DMPC-nanodiscs showed excellent stability and size homogeneity when solubilizing zwitterionic lipids. The stability of DMPC:DMPG non-ionic polymer nanodiscs is attributed to the inter-nanodisc repulsion by the anionic-DMPG that prevents the uncontrolled collision and fusion of nanodiscs. Thus, the reported results demonstrate the use of electrostatic interactions to tune the solubility, stability, and size homogeneity of non-ionic polymer nanodiscs which are important features for enabling functional and atomic-resolution structural studies of membrane proteins, other lipid-binding molecules, and water-soluble biomolecules including cytosolic proteins, nucleic acids and metabolites.
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Affiliation(s)
- Bankala Krishnarjuna
- Biophysics Program, Department of Chemistry, Macromolecular Science and Engineering, Biomedical Engineering, Michigan Neuroscience Institute, The University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Joseph Marte
- Biophysics Program, Department of Chemistry, Macromolecular Science and Engineering, Biomedical Engineering, Michigan Neuroscience Institute, The University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Thirupathi Ravula
- Biophysics Program, Department of Chemistry, Macromolecular Science and Engineering, Biomedical Engineering, Michigan Neuroscience Institute, The University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Ayyalusamy Ramamoorthy
- Biophysics Program, Department of Chemistry, Macromolecular Science and Engineering, Biomedical Engineering, Michigan Neuroscience Institute, The University of Michigan, Ann Arbor, MI 48109-1055, USA.
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15
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Lenz J, Larsen AH, Keller S, Luchini A. Effect of Cholesterol on the Structure and Composition of Glyco-DIBMA Lipid Particles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:3569-3579. [PMID: 36854196 PMCID: PMC10018766 DOI: 10.1021/acs.langmuir.2c03019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 02/16/2023] [Indexed: 06/18/2023]
Abstract
Different amphiphilic co-polymers have been introduced to produce polymer-lipid particles with nanodisc structure composed of an inner lipid bilayer and polymer chains self-assembled as an outer belt. These particles can be used to stabilize membrane proteins in solution and enable their characterization by means of biophysical methods, including small-angle X-ray scattering (SAXS). Some of these co-polymers have also been used to directly extract membrane proteins together with their associated lipids from native membranes. Styrene/maleic acid and diisobutylene/maleic acid are among the most commonly used co-polymers for producing polymer-lipid particles, named SMALPs and DIBMALPs, respectively. Recently, a new co-polymer, named Glyco-DIBMA, was produced by partial amidation of DIBMA with the amino sugar N-methyl-d-glucosamine. Polymer-lipid particles produced with Glyco-DIBMA, named Glyco-DIBMALPs, exhibit improved structural properties and stability compared to those of SMALPs and DIBMALPs while retaining the capability of directly extracting membrane proteins from native membranes. Here, we characterize the structure and lipid composition of Glyco-DIBMALPs produced with either 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) or 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC). Glyco-DIBMALPs were also prepared with mixtures of either POPC or DMPC and cholesterol at different mole fractions. We estimated the lipid content in the Glyco-DIBMALPs and determined the particle structure and morphology by SAXS. We show that the Glyco-DIBMALPs are nanodisc-like particles whose size and shape depend on the polymer/lipid ratio. This is relevant for designing nanodisc particles with a tunable diameter according to the size of the membrane protein to be incorporated. We also report that the addition of >20 mol % cholesterol strongly perturbed the formation of Glyco-DIBMALPs. Altogether, we describe a detailed characterization of the Glyco-DIBMALPs, which provides relevant inputs for future application of these particles in the biophysical investigation of membrane proteins.
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Affiliation(s)
- Julia Lenz
- Molecular
Biophysics, Technische Universität
Kaiserslautern, Erwin-Schrödinger-Strasse
13, 67663 Kaiserslautern, Germany
| | | | - Sandro Keller
- Biophysics,
Institute of Molecular Biosciences (IMB), NAWI Graz, University of Graz, Humboldtstrasse 50/III, 8010 Graz, Austria
- Field
of Excellence BioHealth, University of Graz, 8010 Graz, Austria
- BioTechMed-Graz, 8010 Graz, Austria
| | - Alessandra Luchini
- European
Spallation Source - ERIC, Partikel Gatan, Lund 224
84, Sweden
- Department
of Physics and Geology, University of Perugia, Via Alessandro Pascoli, 06123 Perugia, Italy
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16
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Krishnarjuna B, Ravula T, Faison EM, Tonelli M, Zhang Q, Ramamoorthy A. Polymer-Nanodiscs as a Novel Alignment Medium for High-Resolution NMR-Based Structural Studies of Nucleic Acids. Biomolecules 2022; 12:1628. [PMID: 36358983 PMCID: PMC9687133 DOI: 10.3390/biom12111628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 10/28/2022] [Accepted: 10/31/2022] [Indexed: 11/06/2022] Open
Abstract
Residual dipolar couplings (RDCs) are increasingly used for high-throughput NMR-based structural studies and to provide long-range angular constraints to validate and refine structures of various molecules determined by X-ray crystallography and NMR spectroscopy. RDCs of a given molecule can be measured in an anisotropic environment that aligns in an external magnetic field. Here, we demonstrate the first application of polymer-based nanodiscs for the measurement of RDCs from nucleic acids. Polymer-based nanodiscs prepared using negatively charged SMA-EA polymer and zwitterionic DMPC lipids were characterized by size-exclusion chromatography, 1H NMR, dynamic light-scattering, and 2H NMR. The magnetically aligned polymer-nanodiscs were used as an alignment medium to measure RDCs from a 13C/15N-labeled fluoride riboswitch aptamer using 2D ARTSY-HSQC NMR experiments. The results showed that the alignment of nanodiscs is stable for nucleic acids and nanodisc-induced RDCs fit well with the previously determined solution structure of the riboswitch. These results demonstrate that SMA-EA-based lipid-nanodiscs can be used as a stable alignment medium for high-resolution structural and dynamical studies of nucleic acids, and they can also be applicable to study various other biomolecules and small molecules in general.
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Affiliation(s)
- Bankala Krishnarjuna
- Biophysics Program, Department of Chemistry, Biomedical Engineering, and Macromolecular Science and Engineering, Michigan Neuroscience Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Thirupathi Ravula
- Biophysics Program, Department of Chemistry, Biomedical Engineering, and Macromolecular Science and Engineering, Michigan Neuroscience Institute, University of Michigan, Ann Arbor, MI 48109, USA
- National Magnetic Resonance Facility at Madison, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Edgar M. Faison
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Marco Tonelli
- National Magnetic Resonance Facility at Madison, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Qi Zhang
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Ayyalusamy Ramamoorthy
- Biophysics Program, Department of Chemistry, Biomedical Engineering, and Macromolecular Science and Engineering, Michigan Neuroscience Institute, University of Michigan, Ann Arbor, MI 48109, USA
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