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Secor PR, Burgener EB, Kinnersley M, Jennings LK, Roman-Cruz V, Popescu M, Van Belleghem JD, Haddock N, Copeland C, Michaels LA, de Vries CR, Chen Q, Pourtois J, Wheeler TJ, Milla CE, Bollyky PL. Pf Bacteriophage and Their Impact on Pseudomonas Virulence, Mammalian Immunity, and Chronic Infections. Front Immunol 2020; 11:244. [PMID: 32153575 PMCID: PMC7047154 DOI: 10.3389/fimmu.2020.00244] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 01/30/2020] [Indexed: 12/11/2022] Open
Abstract
Pf bacteriophage are temperate phages that infect the bacterium Pseudomonas aeruginosa, a major cause of chronic lung infections in cystic fibrosis (CF) and other settings. Pf and other temperate phages have evolved complex, mutualistic relationships with their bacterial hosts that impact both bacterial phenotypes and chronic infection. We and others have reported that Pf phages are a virulence factor that promote the pathogenesis of P. aeruginosa infections in animal models and are associated with worse skin and lung infections in humans. Here we review the biology of Pf phage and what is known about its contributions to pathogenesis and clinical disease. First, we review the structure, genetics, and epidemiology of Pf phage. Next, we address the diverse and surprising ways that Pf phages contribute to P. aeruginosa phenotypes including effects on biofilm formation, antibiotic resistance, and motility. Then, we cover data indicating that Pf phages suppress mammalian immunity at sites of bacterial infection. Finally, we discuss recent literature implicating Pf in chronic P. aeruginosa infections in CF and other settings. Together, these reports suggest that Pf bacteriophage have direct effects on P. aeruginosa infections and that temperate phages are an exciting frontier in microbiology, immunology, and human health.
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Affiliation(s)
- Patrick R. Secor
- Division of Biological Sciences, University of Montana, Missoula, MT, United States
- Center for Translational Medicine, University of Montana, Missoula, MT, United States
- Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, MT, United States
| | - Elizabeth B. Burgener
- Department of Pediatrics, Center for Excellence in Pulmonary Biology, Stanford University, Stanford, CA, United States
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA, United States
| | - M. Kinnersley
- Division of Biological Sciences, University of Montana, Missoula, MT, United States
| | - Laura K. Jennings
- Division of Biological Sciences, University of Montana, Missoula, MT, United States
- Center for Translational Medicine, University of Montana, Missoula, MT, United States
| | - Valery Roman-Cruz
- Division of Biological Sciences, University of Montana, Missoula, MT, United States
- Center for Translational Medicine, University of Montana, Missoula, MT, United States
| | - Medeea Popescu
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA, United States
| | - Jonas D. Van Belleghem
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA, United States
| | - Naomi Haddock
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA, United States
| | - Conner Copeland
- Department of Computer Science, University of Montana, Missoula, MT, United States
| | - Lia A. Michaels
- Division of Biological Sciences, University of Montana, Missoula, MT, United States
| | - Christiaan R. de Vries
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA, United States
| | - Qingquan Chen
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA, United States
| | - Julie Pourtois
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA, United States
| | - Travis J. Wheeler
- Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, MT, United States
- Department of Computer Science, University of Montana, Missoula, MT, United States
| | - Carlos E. Milla
- Department of Pediatrics, Center for Excellence in Pulmonary Biology, Stanford University, Stanford, CA, United States
| | - Paul L. Bollyky
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA, United States
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Goldbourt A. Structural characterization of bacteriophage viruses by NMR. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2019; 114-115:192-210. [PMID: 31779880 DOI: 10.1016/j.pnmrs.2019.06.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 06/03/2019] [Accepted: 06/26/2019] [Indexed: 06/10/2023]
Abstract
Magic-angle spinning (MAS) solid-state NMR has provided structural insights into various bacteriophage systems including filamentous, spherical, and tailed bacteriophage viruses. A variety of methodologies have been utilized including elementary two and three-dimensional assignment experiments, proton-detection techniques at fast spinning speeds, non-uniform sampling, structure determination protocols, conformational dynamics revealed by recoupling of anisotropic interactions, and enhancement by dynamic nuclear polarization. This review summarizes most of the studies performed during the last decade by MAS techniques and makes comparisons with prior knowledge obtained from static and solution NMR techniques. Chemical shifts for the capsids of the various systems are reported and analyzed, and DNA shifts are reported and discussed in the context of general high molecular-weight DNA molecules. Chemical shift and torsion angle prediction techniques are compared and applied to the various phage systems. The structures of the intact M13 filamentous bacteriophage and that of the Acinetobacter phage AP205 capsid, determined using MAS-based experimental data, are presented. Finally, filamentous phages, which are highly rigid systems, show interesting dynamics at the interface of the capsid and DNA, and their mutual electrostatic interactions are shown to be mediated by highly mobile positively charged residues. Novel results obtained from recoupling the chemical shift anisotropy of a single arginine in IKe phage, which is in contact with its DNA, further demonstrate this point. MAS NMR thus provides many new insights into phage structure, and on the other hand the richness, complexity and variety of bacteriophage systems provide opportunities for new NMR methodologies and technique developments.
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Affiliation(s)
- Amir Goldbourt
- School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 6997801, Israel.
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3
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Abstract
The filamentous bacteriophage IKe is one of many nonenveloped bacterial viruses that encapsulate a circular single-stranded viral genome in the phage capsid shell. The shell of IKe is comprised of about 3,100 copies of the IKe major coat protein. Atomic-resolution structures of filamentous phages are scarce, and the structure of the single-stranded DNA is a matter of debate. Our cryo-electron microscopy structure of the filamentous bacteriophage IKe at a resolution of 3.4 Å provides atomic details on the structure of the major coat protein, the symmetry of the capsid shell, and the key interactions driving its assembly. We propose a model for the conformation of the circular single-stranded DNA core and the interactions between the capsid shell and inner DNA core. The filamentous bacteriophage IKe infects Escherichia coli cells bearing IncN pili. We report the cryo-electron microscopy structure of the micrometer-long IKe viral particle at a resolution of 3.4 Å. The major coat protein [protein 8 (p8)] consists of 47 residues that fold into a ∼68-Å-long helix. An atomic model of the coat protein was built. Five p8 helices in a horizontal layer form a pentamer, and symmetrically neighboring p8 layers form a right-handed helical cylinder having a rise per pentamer of 16.77 Å and a twist of 38.52°. The inner surface of the capsid cylinder is positively charged and has direct interactions with the encapsulated circular single-stranded DNA genome, which has an electron density consistent with an unusual left-handed helix structure. Similar to capsid structures of other filamentous viruses, strong capsid packing in the IKe particle is maintained by hydrophobic residues. Despite having a different length and large sequence differences from other filamentous phages, π–π interactions were found between Tyr9 of one p8 and Trp29 of a neighboring p8 in IKe that are similar to interactions observed in phage M13, suggesting that, despite sequence divergence, overall structural features are maintained.
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Abstract
Filamentous bacteriophages, also known as filamentous bacterial viruses or Inoviruses, have been studied extensively over the years. They are interesting paradigms in structural molecular biology and offer insight into molecular assembly, a process that remains to be fully understood. In this chapter, an overview on filamentous bacteriophages will be provided. In particular, we review the constituent proteins of filamentous bacteriophage and discuss assembly by examining the structure of the major coat protein at various stages of the process. The minor coat proteins will also be briefly reviewed. Structural information provides key snapshots into the dynamic process of assembly.
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Schwieters CD, Bermejo GA, Clore GM. Xplor-NIH for molecular structure determination from NMR and other data sources. Protein Sci 2017; 27:26-40. [PMID: 28766807 DOI: 10.1002/pro.3248] [Citation(s) in RCA: 151] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 07/28/2017] [Indexed: 11/10/2022]
Abstract
Xplor-NIH is a popular software package for biomolecular structure determination from nuclear magnetic resonance (NMR) and other data sources. Here, some of Xplor-NIH's most useful data-associated energy terms are reviewed, including newer alternative options for using residual dipolar coupling data in structure calculations. Further, we discuss new developments in the implementation of strict symmetry for the calculation of symmetric homo-oligomers, and in the representation of the system as an ensemble of structures to account for motional effects. Finally, the different available force fields are presented, among other Xplor-NIH capabilities.
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Affiliation(s)
- Charles D Schwieters
- Imaging Sciences Laboratory, Center for Information Technology, National Institutes of Health, Bethesda, Maryland, 20892-5624
| | - Guillermo A Bermejo
- Imaging Sciences Laboratory, Center for Information Technology, National Institutes of Health, Bethesda, Maryland, 20892-5624
| | - G Marius Clore
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, 20892-0520
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6
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Fibre diffraction studies of biological macromolecules. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2017; 127:43-87. [DOI: 10.1016/j.pbiomolbio.2017.04.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 03/21/2017] [Accepted: 04/05/2017] [Indexed: 12/27/2022]
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7
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Sergeyev IV, Itin B, Rogawski R, Day LA, McDermott AE. Efficient assignment and NMR analysis of an intact virus using sequential side-chain correlations and DNP sensitization. Proc Natl Acad Sci U S A 2017; 114:5171-5176. [PMID: 28461483 PMCID: PMC5441803 DOI: 10.1073/pnas.1701484114] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
An experimental strategy has been developed to increase the efficiency of dynamic nuclear polarization (DNP) in solid-state NMR studies. The method makes assignments simpler, faster, and more reliable via sequential correlations of both side-chain and Cα resonances. The approach is particularly suited to complex biomolecules and systems with significant chemical-shift degeneracy. It was designed to overcome the spectral congestion and line broadening that occur due to sample freezing at the cryogenic temperatures required for DNP. Nonuniform sampling (NUS) is incorporated to achieve time-efficient collection of multidimensional data. Additionally, fast (25 kHz) magic-angle spinning (MAS) provides optimal sensitivity and resolution. Data collected in <1 wk produced a virtually complete de novo assignment of the coat protein of Pf1 virus. The peak positions and linewidths for samples near 100 K are perturbed relative to those near 273 K. These temperature-induced perturbations are strongly correlated with hydration surfaces.
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Affiliation(s)
- Ivan V Sergeyev
- Department of Chemistry, Columbia University, New York, NY 10027
| | - Boris Itin
- New York Structural Biology Center, New York, NY 10027
| | - Rivkah Rogawski
- Department of Chemistry, Columbia University, New York, NY 10027
| | - Loren A Day
- Public Health Research Institute, Rutgers University, Newark, NJ 07103
| | - Ann E McDermott
- Department of Chemistry, Columbia University, New York, NY 10027;
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8
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Habenstein B, Loquet A. Solid-state NMR: An emerging technique in structural biology of self-assemblies. Biophys Chem 2016; 210:14-26. [DOI: 10.1016/j.bpc.2015.07.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Accepted: 07/08/2015] [Indexed: 12/13/2022]
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9
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Sergeyev IV, Bahri S, Day LA, McDermott AE. Pf1 bacteriophage hydration by magic angle spinning solid-state NMR. J Chem Phys 2015; 141:22D533. [PMID: 25494804 DOI: 10.1063/1.4903230] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
High resolution two- and three-dimensional heteronuclear correlation spectroscopy ((1)H-(13)C, (1)H-(15)N, and (1)H-(13)C-(13)C HETCOR) has provided a detailed characterization of the internal and external hydration water of the Pf1 virion. This long and slender virion (2000 nm × 7 nm) contains highly stretched DNA within a capsid of small protein subunits, each only 46 amino acid residues. HETCOR cross-peaks have been unambiguously assigned to 25 amino acids, including most external residues 1-21 as well as residues 39-40 and 43-46 deep inside the virion. In addition, the deoxyribose rings of the DNA near the virion axis are in contact with water. The sets of cross-peaks to the DNA and to all 25 amino acid residues were from the same hydration water (1)H resonance; some of the assigned residues do not have exchangeable side-chain protons. A mapping of the contacts onto structural models indicates the presence of water "tunnels" through a highly hydrophobic region of the capsid. The present results significantly extend and modify results from a lower resolution study, and yield a comprehensive hydration surface map of Pf1. In addition, the internal water could be distinguished from external hydration water by means of paramagnetic relaxation enhancement. The internal water population may serve as a conveniently localized magnetization reservoir for structural studies.
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Affiliation(s)
- Ivan V Sergeyev
- Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, USA
| | - Salima Bahri
- Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, USA
| | - Loren A Day
- Public Health Research Institute, Rutgers University, 225 Warren St., Newark, New Jersey 07103, USA
| | - Ann E McDermott
- Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, USA
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10
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Potrzebowski W, André I. Automated determination of fibrillar structures by simultaneous model building and fiber diffraction refinement. Nat Methods 2015; 12:679-84. [DOI: 10.1038/nmeth.3399] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Accepted: 03/20/2015] [Indexed: 11/09/2022]
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11
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Egelman EH. Three-dimensional reconstruction of helical polymers. Arch Biochem Biophys 2015; 581:54-8. [PMID: 25912526 DOI: 10.1016/j.abb.2015.04.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 04/06/2015] [Accepted: 04/14/2015] [Indexed: 11/18/2022]
Abstract
The field of three-dimensional electron microscopy began more than 45years ago with a reconstruction of a helical phage tail, and helical polymers continue to be important objects for three-dimensional reconstruction due to the centrality of helical protein and nucleoprotein polymers in all aspects of biology. We are now witnessing a fundamental revolution in this area, made possible by direct electron detectors, which has led to near-atomic resolution for a number of important helical structures. Most importantly, the possibility of achieving such resolution routinely for a vast number of helical samples is within our reach. One of the main problems in helical reconstruction, ambiguities in assigning the helical symmetry, is overcome when one reaches a resolution where secondary structure is clearly visible. However, obstacles still exist due to the intrinsic variability within many helical filaments.
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Affiliation(s)
- Edward H Egelman
- Department of Biochemistry and Molecular Genetics, University of Virginia, Box 800733, Charlottesville, VA 22908, USA.
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12
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Abramov G, Morag O, Goldbourt A. Magic-angle spinning NMR of intact bacteriophages: insights into the capsid, DNA and their interface. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2015; 253:80-90. [PMID: 25797007 DOI: 10.1016/j.jmr.2015.01.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2014] [Revised: 01/05/2015] [Accepted: 01/18/2015] [Indexed: 06/04/2023]
Abstract
Bacteriophages are viruses that infect bacteria. They are complex macromolecular assemblies, which are composed of multiple protein subunits that protect genomic material and deliver it to specific hosts. Various biophysical techniques have been used to characterize their structure in order to unravel phage morphogenesis. Yet, most bacteriophages are non-crystalline and have very high molecular weights, in the order of tens of MegaDaltons. Therefore, complete atomic-resolution characterization on such systems that encompass both capsid and DNA is scarce. In this perspective article we demonstrate how magic-angle spinning solid-state NMR has and is used to characterize in detail bacteriophage viruses, including filamentous and icosahedral phage. We discuss the process of sample preparation, spectral assignment of both capsid and DNA and the use of chemical shifts and dipolar couplings to probe the capsid-DNA interface, describe capsid structure and dynamics and extract structural differences between viruses.
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Affiliation(s)
- Gili Abramov
- School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Ramat Aviv 69978, Tel Aviv, Israel
| | - Omry Morag
- School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Ramat Aviv 69978, Tel Aviv, Israel
| | - Amir Goldbourt
- School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Ramat Aviv 69978, Tel Aviv, Israel.
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13
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Marvin DA, Symmons MF, Straus SK. Structure and assembly of filamentous bacteriophages. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2014; 114:80-122. [PMID: 24582831 DOI: 10.1016/j.pbiomolbio.2014.02.003] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Accepted: 02/09/2014] [Indexed: 12/24/2022]
Abstract
Filamentous bacteriophages are interesting paradigms in structural molecular biology, in part because of the unusual mechanism of filamentous phage assembly. During assembly, several thousand copies of an intracellular DNA-binding protein bind to each copy of the replicating phage DNA, and are then displaced by membrane-spanning phage coat proteins as the nascent phage is extruded through the bacterial plasma membrane. This complicated process takes place without killing the host bacterium. The bacteriophage is a semi-flexible worm-like nucleoprotein filament. The virion comprises a tube of several thousand identical major coat protein subunits around a core of single-stranded circular DNA. Each protein subunit is a polymer of about 50 amino-acid residues, largely arranged in an α-helix. The subunits assemble into a helical sheath, with each subunit oriented at a small angle to the virion axis and interdigitated with neighbouring subunits. A few copies of "minor" phage proteins necessary for infection and/or extrusion of the virion are located at each end of the completed virion. Here we review both the structure of the virion and aspects of its function, such as the way the virion enters the host, multiplies, and exits to prey on further hosts. In particular we focus on our understanding of the way the components of the virion come together during assembly at the membrane. We try to follow a basic rule of empirical science, that one should chose the simplest theoretical explanation for experiments, but be prepared to modify or even abandon this explanation as new experiments add more detail.
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Affiliation(s)
- D A Marvin
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, UK.
| | - M F Symmons
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, UK
| | - S K Straus
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC V6T 1Z1, Canada.
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14
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Vostrikov VV, Mote KR, Verardi R, Veglia G. Structural dynamics and topology of phosphorylated phospholamban homopentamer reveal its role in the regulation of calcium transport. Structure 2013; 21:2119-30. [PMID: 24207128 DOI: 10.1016/j.str.2013.09.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 09/07/2013] [Accepted: 09/11/2013] [Indexed: 01/25/2023]
Abstract
Phospholamban (PLN) inhibits the sarco(endo)plasmic reticulum Ca²⁺-ATPase (SERCA), thereby regulating cardiac diastole. In membranes, PLN assembles into homopentamers that in both the phosphorylated and nonphosphorylated states have been proposed to form ion-selective channels. Here, we determined the structure of the phosphorylated pentamer using a combination of solution and solid-state nuclear magnetic resonance methods. We found that the pinwheel architecture of the homopentamer is preserved upon phosphorylation, with each monomer having an L-shaped conformation. The TM domains form a hydrophobic pore approximately 24 Å long and 2 Å in diameter, which is inconsistent with canonical Ca²⁺-selective channels. Phosphorylation, however, enhances the conformational dynamics of the cytoplasmic region of PLN, causing partial unwinding of the amphipathic helix. We propose that PLN oligomers act as storage for active monomers, keeping SERCA function within a physiological window.
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Affiliation(s)
- Vitaly V Vostrikov
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
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15
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McDonald M, Box H, Bian W, Kendall A, Tycko R, Stubbs G. Fiber diffraction data indicate a hollow core for the Alzheimer's aβ 3-fold symmetric fibril. J Mol Biol 2012; 423:454-61. [PMID: 22903058 DOI: 10.1016/j.jmb.2012.08.004] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2012] [Revised: 07/11/2012] [Accepted: 08/09/2012] [Indexed: 10/28/2022]
Abstract
Amyloid β protein (Aβ), the principal component of the extracellular plaques found in the brains of patients with Alzheimer's disease, forms fibrils well suited to structural study by X-ray fiber diffraction. Fiber diffraction patterns from the 40-residue form Aβ(1-40) confirm a number of features of a 3-fold symmetric Aβ model from solid-state NMR (ssNMR) but suggest that the fibrils have a hollow core not present in the original ssNMR models. Diffraction patterns calculated from a revised 3-fold hollow model with a more regular β-sheet structure are in much better agreement with the observed diffraction data than patterns calculated from the original ssNMR model. Refinement of a hollow-core model against ssNMR data led to a revised ssNMR model, similar to the fiber diffraction model.
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Affiliation(s)
- Michele McDonald
- Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235-1634, USA
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16
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Verardi R, Traaseth NJ, Masterson LR, Vostrikov VV, Veglia G. Isotope labeling for solution and solid-state NMR spectroscopy of membrane proteins. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 992:35-62. [PMID: 23076578 PMCID: PMC3555569 DOI: 10.1007/978-94-007-4954-2_3] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In this chapter, we summarize the isotopic labeling strategies used to obtain high-quality solution and solid-state NMR spectra of biological samples, with emphasis on integral membrane proteins (IMPs). While solution NMR is used to study IMPs under fast tumbling conditions, such as in the presence of detergent micelles or isotropic bicelles, solid-state NMR is used to study the structure and orientation of IMPs in lipid vesicles and bilayers. In spite of the tremendous progress in biomolecular NMR spectroscopy, the homogeneity and overall quality of the sample is still a substantial obstacle to overcome. Isotopic labeling is a major avenue to simplify overlapped spectra by either diluting the NMR active nuclei or allowing the resonances to be separated in multiple dimensions. In the following we will discuss isotopic labeling approaches that have been successfully used in the study of IMPs by solution and solid-state NMR spectroscopy.
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Affiliation(s)
- Raffaello Verardi
- 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
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17
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Abramov G, Morag O, Goldbourt A. Magic-Angle Spinning NMR of a Class I Filamentous Bacteriophage Virus. J Phys Chem B 2011; 115:9671-80. [DOI: 10.1021/jp2040955] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gili Abramov
- School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Ramat Aviv 69978, Tel Aviv, Israel
| | - Omry Morag
- School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Ramat Aviv 69978, Tel Aviv, Israel
| | - Amir Goldbourt
- School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Ramat Aviv 69978, Tel Aviv, Israel
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