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Jønsson R, Björling A, Midtgaard SR, Jensen GV, Skar-Gislinge N, Arleth L, Matthews S, Krogfelt KA, Jenssen H. Aggregative adherence fimbriae form compact structures as seen by SAXS. Sci Rep 2023; 13:16516. [PMID: 37783694 PMCID: PMC10545799 DOI: 10.1038/s41598-023-42079-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 09/05/2023] [Indexed: 10/04/2023] Open
Abstract
Bacterial colonization is mediated by fimbriae, which are thin hair-like appendages dispersed from the bacterial surface. The aggregative adherence fimbriae from enteroaggregative E. coli are secreted through the outer membrane and consist of polymerized minor and major pilin subunits. Currently, the understanding of the structural morphology and the role of the minor pilin subunit in the polymerized fimbriae are limited. In this study we use small-angle X-ray scattering to reveal the structural morphology of purified fimbriae in solution. We show that the aggregative fimbriae are compact arrangements of subunit proteins Agg5A + Agg3B which are assembled pairwise on a flexible string rather than extended in relatively straight filaments. Absence of the minor subunit leads to less compact fimbriae, but did not affect the length. The study provides novel insights into the structural morphology and assembly of the aggregative adherence fimbriae. Our study suggests that the minor subunit is not located at the tip of the fimbriae as previously speculated but has a higher importance for the assembled fimbriae by affecting the global structure.
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Affiliation(s)
- Rie Jønsson
- Department of Science and Environment, Roskilde University, 4000, Roskilde, Denmark.
| | | | | | | | | | - Lise Arleth
- Niels Bohr Institute, Universitetsparken 5, 2100, Copenhagen, Denmark
| | - Steve Matthews
- Department of Life Sciences, Centre for Structural Biology, Imperial College London, South Kensington, London, UK
| | | | - Håvard Jenssen
- Department of Science and Environment, Roskilde University, 4000, Roskilde, Denmark.
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2
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Mishra NK, Østergaard M, Midtgaard SR, Strindberg SS, Winkler S, Wu S, Sørensen TJ, Hassenkam T, Poulsen JCN, Lo Leggio L, Nielsen HM, Arleth L, Christensen NJ, Thulstrup PW, Jensen KJ. Controlling the fractal dimension in self-assembly of terpyridine modified insulin by Fe 2+ and Eu 3+ to direct in vivo effects. Nanoscale 2021; 13:8467-8473. [PMID: 33984105 DOI: 10.1039/d1nr00414j] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Metal ion-induced self-assembly (SA) of proteins into higher-order structures can provide new, dynamic nano-assemblies. Here, the synthesis and characterization of a human insulin (HI) analog modified at LysB29 with the tridentate chelator 2,2':6',2''-terpyridine (Tpy) is described. SA of this new insulin analog (LysB29Tpy-HI) in the presence of the metal ions Fe2+ and Eu3+ at different concentrations was studied in solution by fluorescence luminescence and CD spectroscopy, dynamic light scattering, and small-angle X-ray scattering, while surface assembly was probed by AFM. Unique oligomerization was observed in solution, as Fe2+ yielded small magenta-colored discrete non-native assemblies, while Eu3+ caused the formation of large fractal assemblies. Binding of both metal ions to Tpy was demonstrated spectroscopically, and emission lifetime experiments revealed a distinct Eu3+ coordination geometry that included two water molecules. SAXS suggested that LysB29Tpy-HI with Fe2+ oligomerized to a discrete, roughly octameric species, while LysB29Tpy-HI with Eu3+ gave very large assemblies that could be modelled as fractals. The fractal dimensionality increased with the Eu3+ concentration. We propose that this is a consequence of Eu3+ binding to both Tpy and to free carboxylic acid groups on the insulin surface. LysB29Tpy-HI maintained insulin receptor affinity, and showed extended blood glucose lowering and plasma concentration after subcutaneous injection in rats. The combination of metal ion directed SA and native SA provides control of nano-scale fractal dimensionality and points towards use in therapeutics.
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Affiliation(s)
- Narendra Kumar Mishra
- Center for Biopharmaceuticals and Biobarriers in Drug Delivery and Department of Chemistry, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark.
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3
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Larsen AH, Johansen NT, Gajhede M, Arleth L, Midtgaard SR. Lipid-bound ApoE3 self-assemble into elliptical disc-shaped particles. Biochim Biophys Acta Biomembr 2020; 1863:183495. [PMID: 33189719 DOI: 10.1016/j.bbamem.2020.183495] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 10/14/2020] [Accepted: 10/26/2020] [Indexed: 11/29/2022]
Abstract
Apolipoproteins are vital to lipid metabolism and cholesterol transport in the human body. Here we present a structural study of the lipid-bound particles formed by ApoE3 in a full-length and a truncated version. The particles are formed with, respectively, POPC and DMPC and investigated by small-angle X-ray scattering and negative stain electron microscopy. We find that lipid-bound ApoE3 particles are elliptical, disc-shaped particles composed of a central lipid bilayer encircled by two amphipathic ApoE3 proteins. We went on to investigate a truncated form of ApoE3 containing only residue 80 to 255 (ApoE380-255), which is the central helical repeat segment of ApoE3. The lipid-bound ApoE380-255 particles are found to have the same morphology as the particles with full-length ApoE3. However, they are larger, and form more heterogeneous discoidal structures with four proteins per particle. This behavior is in contrast to ApoA1 where the highly similar helical repeat domain determines the size and stoichiometry of the formed particles both in the case of full-length and truncated ApoA1. Our data hence points towards different mechanisms for lipid bilayer structural modulation by ApoA1 and ApoE3 due to different roles of the non-repeat segments.
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Affiliation(s)
- Andreas Haahr Larsen
- University of Copenhagen, Niels Bohr Institute, Copenhagen, Denmark; University of Oxford, Department of Biochemistry, Oxford, United Kingdom.
| | | | - Michael Gajhede
- University of Copenhagen, Department of Drug Design and Pharmacology, Copenhagen, Denmark
| | - Lise Arleth
- University of Copenhagen, Niels Bohr Institute, Copenhagen, Denmark.
| | - Søren Roi Midtgaard
- University of Copenhagen, Niels Bohr Institute, Copenhagen, Denmark; Boston University School of Medicine, Department of Physiology and Biophysics, Boston, USA
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4
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Bucciarelli S, Midtgaard SR, Nors Pedersen M, Skou S, Arleth L, Vestergaard B. Size-exclusion chromatography small-angle X-ray scattering of water soluble proteins on a laboratory instrument. J Appl Crystallogr 2018; 51:1623-1632. [PMID: 30546289 PMCID: PMC6276278 DOI: 10.1107/s1600576718014462] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 10/13/2018] [Indexed: 11/16/2022] Open
Abstract
Coupling of size-exclusion chromatography with biological solution small-angle X-ray scattering (SEC-SAXS) on dedicated synchrotron beamlines enables structural analysis of challenging samples such as labile proteins and low-affinity complexes. For this reason, the approach has gained increased popularity during the past decade. Transportation of perishable samples to synchrotrons might, however, compromise the experiments, and the limited availability of synchrotron beamtime renders iterative sample optimization tedious and lengthy. Here, the successful setup of laboratory-based SEC-SAXS is described in a proof-of-concept study. It is demonstrated that sufficient quality data can be obtained on a laboratory instrument with small sample consumption, comparable to typical synchrotron SEC-SAXS demands. UV/vis measurements directly on the SAXS exposure cell ensure accurate concentration determination, crucial for direct molecular weight determination from the scattering data. The absence of radiation damage implies that the sample can be fractionated and subjected to complementary analysis available at the home institution after SEC-SAXS. Laboratory-based SEC-SAXS opens the field for analysis of biological samples at the home institution, thus increasing productivity of biostructural research. It may further ensure that synchrotron beamtime is used primarily for the most suitable and optimized samples.
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Affiliation(s)
- Saskia Bucciarelli
- Department of Drug Design and Pharmacology, University of Copenhagen, Denmark
| | - Søren Roi Midtgaard
- Structural Biophysics, X-ray and Neutron Science, The Niels Bohr Institute, University of Copenhagen, Denmark
| | - Martin Nors Pedersen
- Structural Biophysics, X-ray and Neutron Science, The Niels Bohr Institute, University of Copenhagen, Denmark
| | | | - Lise Arleth
- Structural Biophysics, X-ray and Neutron Science, The Niels Bohr Institute, University of Copenhagen, Denmark
| | - Bente Vestergaard
- Department of Drug Design and Pharmacology, University of Copenhagen, Denmark
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5
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Larsen AH, Dorosz J, Thorsen TS, Johansen NT, Darwish T, Midtgaard SR, Arleth L, Kastrup JS. Small-angle neutron scattering studies on the AMPA receptor GluA2 in the resting, AMPA-bound and GYKI-53655-bound states. IUCrJ 2018; 5:780-793. [PMID: 30443361 PMCID: PMC6211538 DOI: 10.1107/s2052252518012186] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 08/28/2018] [Indexed: 06/09/2023]
Abstract
The AMPA receptor GluA2 belongs to the family of ionotropic glutamate receptors, which are responsible for most of the fast excitatory neuronal signalling in the central nervous system. These receptors are important for memory and learning, but have also been associated with brain diseases such as Alzheimer's disease and epilepsy. Today, one drug is on the market for the treatment of epilepsy targeting AMPA receptors, i.e. a negative allosteric modulator of these receptors. Recently, crystal structures and cryo-electron microscopy (cryo-EM) structures of full-length GluA2 in the resting (apo), activated and desensitized states have been reported. Here, solution structures of full-length GluA2 are reported using small-angle neutron scattering (SANS) with a novel, fully matched-out detergent. The GluA2 solution structure was investigated in the resting state as well as in the presence of AMPA and of the negative allosteric modulator GYKI-53655. In solution and at neutral pH, the SANS data clearly indicate that GluA2 is in a compact form in the resting state. The solution structure resembles the crystal structure of GluA2 in the resting state, with an estimated maximum distance (D max) of 179 ± 11 Å and a radius of gyration (R g) of 61.9 ± 0.4 Å. An ab initio model of GluA2 in solution generated using DAMMIF clearly showed the individual domains, i.e. the extracellular N-terminal domains and ligand-binding domains as well as the transmembrane domain. Solution structures revealed that GluA2 remained in a compact form in the presence of AMPA or GYKI-53655. At acidic pH only, GluA2 in the presence of AMPA adopted a more open conformation of the extracellular part (estimated D max of 189 ± 5 Å and R g of 65.2 ± 0.5 Å), resembling the most open, desensitized class 3 cryo-EM structure of GluA2 in the presence of quisqualate. In conclusion, this methodological study may serve as an example for future SANS studies on membrane proteins.
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Affiliation(s)
- Andreas Haahr Larsen
- Structural Biophysics, X-ray and Neutron Science, The Niels Bohr Institute, University of Copenhagen, Denmark
| | - Jerzy Dorosz
- Biostructural Research, Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Thor Seneca Thorsen
- Biostructural Research, Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Nicolai Tidemand Johansen
- Structural Biophysics, X-ray and Neutron Science, The Niels Bohr Institute, University of Copenhagen, Denmark
| | - Tamim Darwish
- National Deuteration Facility, Australian Nuclear Science and Technology Organization, Australia
| | - Søren Roi Midtgaard
- Structural Biophysics, X-ray and Neutron Science, The Niels Bohr Institute, University of Copenhagen, Denmark
| | - Lise Arleth
- Structural Biophysics, X-ray and Neutron Science, The Niels Bohr Institute, University of Copenhagen, Denmark
| | - Jette Sandholm Kastrup
- Biostructural Research, Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
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6
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Midtgaard SR, Darwish TA, Pedersen MC, Huda P, Larsen AH, Jensen GV, Kynde SAR, Skar‐Gislinge N, Nielsen AJZ, Olesen C, Blaise M, Dorosz JJ, Thorsen TS, Venskutonytė R, Krintel C, Møller JV, Frielinghaus H, Gilbert EP, Martel A, Kastrup JS, Jensen PE, Nissen P, Arleth L. Invisible detergents for structure determination of membrane proteins by small‐angle neutron scattering. FEBS J 2017; 285:357-371. [DOI: 10.1111/febs.14345] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 10/20/2017] [Accepted: 11/21/2017] [Indexed: 12/23/2022]
Affiliation(s)
- Søren Roi Midtgaard
- Structural Biophysics X‐ray and Neutron Science The Niels Bohr Institute University of Copenhagen Denmark
| | - Tamim A. Darwish
- National Deuteration Facility Australian Nuclear Science and Technology Organization Lucas Heights Australia
| | - Martin Cramer Pedersen
- Structural Biophysics X‐ray and Neutron Science The Niels Bohr Institute University of Copenhagen Denmark
- Department of Applied Mathematics Research School of Physics and Engineering Australian National University Canberra Australia
| | - Pie Huda
- Structural Biophysics X‐ray and Neutron Science The Niels Bohr Institute University of Copenhagen Denmark
| | - Andreas Haahr Larsen
- Structural Biophysics X‐ray and Neutron Science The Niels Bohr Institute University of Copenhagen Denmark
| | - Grethe Vestergaard Jensen
- Structural Biophysics X‐ray and Neutron Science The Niels Bohr Institute University of Copenhagen Denmark
| | | | - Nicholas Skar‐Gislinge
- Structural Biophysics X‐ray and Neutron Science The Niels Bohr Institute University of Copenhagen Denmark
| | | | - Claus Olesen
- Department of Biomedicine Aarhus University Denmark
| | - Mickael Blaise
- Institut de Recherche en Infectiologie de Montpellier CNRS Université de Montpellier France
- Centre for Carbohydrate Recognition and Signaling Department of Molecular Biology Aarhus University Denmark
| | - Jerzy Józef Dorosz
- Department of Drug Design and Pharmacology Faculty of Health and Medical Sciences University of Copenhagen Denmark
| | - Thor Seneca Thorsen
- Department of Drug Design and Pharmacology Faculty of Health and Medical Sciences University of Copenhagen Denmark
| | - Raminta Venskutonytė
- Department of Drug Design and Pharmacology Faculty of Health and Medical Sciences University of Copenhagen Denmark
| | - Christian Krintel
- Department of Drug Design and Pharmacology Faculty of Health and Medical Sciences University of Copenhagen Denmark
| | - Jesper V. Møller
- Department of Biomedicine Aarhus University Denmark
- Department of Molecular Biology and Genetics Centre for Membrane Pumps in Cells and Disease – PUMPkin Danish National Research Foundation Aarhus University Denmark
| | | | - Elliot Paul Gilbert
- Australian Centre for Neutron Scattering Australian Nuclear Science and Technology Organization Lucas Heights Australia
| | | | - Jette Sandholm Kastrup
- Department of Drug Design and Pharmacology Faculty of Health and Medical Sciences University of Copenhagen Denmark
| | - Poul Erik Jensen
- Copenhagen Plant Science Center University of Copenhagen Denmark
| | - Poul Nissen
- Department of Molecular Biology and Genetics Centre for Membrane Pumps in Cells and Disease – PUMPkin Danish National Research Foundation Aarhus University Denmark
- DANDRITE Nordic‐EMBL Partnership for Molecular Medicine Aarhus University Denmark
| | - Lise Arleth
- Structural Biophysics X‐ray and Neutron Science The Niels Bohr Institute University of Copenhagen Denmark
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7
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van Witteloostuijn SB, Dalbøge LS, Hansen G, Midtgaard SR, Jensen GV, Jensen KJ, Vrang N, Jelsing J, Pedersen SL. GUB06-046, a novel secretin/glucagon-like peptide 1 co-agonist, decreases food intake, improves glycemic control, and preserves beta cell mass in diabetic mice. J Pept Sci 2017; 23:845-854. [DOI: 10.1002/psc.3048] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 09/18/2017] [Accepted: 09/19/2017] [Indexed: 12/17/2022]
Affiliation(s)
- Søren B. van Witteloostuijn
- Gubra ApS; Hørsholm Kongevej 11B 2970 Hørsholm Denmark
- Department of Chemistry, Faculty of Science; University of Copenhagen; Thorvaldsensvej 40 1871 Frederiksberg C Denmark
| | | | - Gitte Hansen
- Gubra ApS; Hørsholm Kongevej 11B 2970 Hørsholm Denmark
| | - Søren Roi Midtgaard
- The Niels Bohr Institute, Faculty of Science; University of Copenhagen; Universitetsparken 5 2100 Copenhagen Denmark
| | - Grethe Vestergaard Jensen
- The Niels Bohr Institute, Faculty of Science; University of Copenhagen; Universitetsparken 5 2100 Copenhagen Denmark
| | - Knud J. Jensen
- Department of Chemistry, Faculty of Science; University of Copenhagen; Thorvaldsensvej 40 1871 Frederiksberg C Denmark
| | - Niels Vrang
- Gubra ApS; Hørsholm Kongevej 11B 2970 Hørsholm Denmark
| | - Jacob Jelsing
- Gubra ApS; Hørsholm Kongevej 11B 2970 Hørsholm Denmark
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8
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Lou C, Christensen NJ, Martos-Maldonado MC, Midtgaard SR, Ejlersen M, Thulstrup PW, Sørensen KK, Jensen KJ, Wengel J. Inside Back Cover: Folding Topology of a Short Coiled-Coil Peptide Structure Templated by an Oligonucleotide Triplex (Chem. Eur. J. 39/2017). Chemistry 2017. [DOI: 10.1002/chem.201701745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Chenguang Lou
- Biomolecular Nanoscale Engineering Center; Department of Physics, Chemistry and Pharmacy; University of Southern Denmark; Campusvej 55 5230 Odense M Denmark
| | - Niels Johan Christensen
- Biomolecular Nanoscale Engineering Center; Department of Chemistry; University of Copenhagen; Thorvaldsensvej 40 1871 Frederiksberg Denmark
| | - Manuel C. Martos-Maldonado
- Biomolecular Nanoscale Engineering Center; Department of Chemistry; University of Copenhagen; Thorvaldsensvej 40 1871 Frederiksberg Denmark
| | - Søren Roi Midtgaard
- Niels Bohr Institute; University of Copenhagen; Universitetsparken 5 2100 Copenhagen Ø Denmark
| | - Maria Ejlersen
- Biomolecular Nanoscale Engineering Center; Department of Physics, Chemistry and Pharmacy; University of Southern Denmark; Campusvej 55 5230 Odense M Denmark
| | - Peter W. Thulstrup
- Department of Chemistry; University of Copenhagen; Universitetsparken 5 2100 Copenhagen Ø Denmark
| | - Kasper K. Sørensen
- Biomolecular Nanoscale Engineering Center; Department of Chemistry; University of Copenhagen; Thorvaldsensvej 40 1871 Frederiksberg Denmark
| | - Knud J. Jensen
- Biomolecular Nanoscale Engineering Center; Department of Chemistry; University of Copenhagen; Thorvaldsensvej 40 1871 Frederiksberg Denmark
| | - Jesper Wengel
- Biomolecular Nanoscale Engineering Center; Department of Physics, Chemistry and Pharmacy; University of Southern Denmark; Campusvej 55 5230 Odense M Denmark
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9
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Lou C, Christensen NJ, Martos-Maldonado MC, Midtgaard SR, Ejlersen M, Thulstrup PW, Sørensen KK, Jensen KJ, Wengel J. Folding Topology of a Short Coiled-Coil Peptide Structure Templated by an Oligonucleotide Triplex. Chemistry 2017; 23:9297-9305. [PMID: 28383784 DOI: 10.1002/chem.201700971] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Indexed: 12/29/2022]
Abstract
The rational design of a well-defined protein-like tertiary structure formed by small peptide building blocks is still a formidable challenge. By using peptide-oligonucleotide conjugates (POC) as building blocks, we present the self-assembly of miniature coiled-coil α-helical peptides guided by oligonucleotide duplex and triplex formation. POC synthesis was achieved by copper-free alkyne-azide cycloaddition between three oligonucleotides and a 23-mer peptide, which by itself exhibited multiple oligomeric states in solution. The oligonucleotide domain was designed to furnish a stable parallel triplex under physiological pH, and to be capable of templating the three peptide sequences to constitute a small coiled-coil motif displaying remarkable α-helicity. The formed trimeric complex was characterized by ultraviolet thermal denaturation, gel electrophoresis, circular dichroism (CD) spectroscopy, small-angle X-ray scattering (SAXS), and molecular modeling. Stabilizing cooperativity was observed between the trimeric peptide and the oligonucleotide triplex domains, and the overall molecular size (ca. 12 nm) in solution was revealed to be independent of concentration. The topological folding of the peptide moiety differed strongly from those of the individual POC strands and the unconjugated peptide, exclusively adopting the designed triple helical structure.
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Affiliation(s)
- Chenguang Lou
- Biomolecular Nanoscale Engineering Center, Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark
| | - Niels Johan Christensen
- Biomolecular Nanoscale Engineering Center, Department of Chemistry, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg, Denmark
| | - Manuel C Martos-Maldonado
- Biomolecular Nanoscale Engineering Center, Department of Chemistry, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg, Denmark
| | - Søren Roi Midtgaard
- Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen Ø, Denmark
| | - Maria Ejlersen
- Biomolecular Nanoscale Engineering Center, Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark
| | - Peter W Thulstrup
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen Ø, Denmark
| | - Kasper K Sørensen
- Biomolecular Nanoscale Engineering Center, Department of Chemistry, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg, Denmark
| | - Knud J Jensen
- Biomolecular Nanoscale Engineering Center, Department of Chemistry, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg, Denmark
| | - Jesper Wengel
- Biomolecular Nanoscale Engineering Center, Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark
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10
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Lou C, Martos-Maldonado MC, Madsen CS, Thomsen RP, Midtgaard SR, Christensen NJ, Kjems J, Thulstrup PW, Wengel J, Jensen KJ. Peptide-oligonucleotide conjugates as nanoscale building blocks for assembly of an artificial three-helix protein mimic. Nat Commun 2016; 7:12294. [PMID: 27464951 PMCID: PMC4974474 DOI: 10.1038/ncomms12294] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 06/15/2016] [Indexed: 01/22/2023] Open
Abstract
Peptide-based structures can be designed to yield artificial proteins with specific folding patterns and functions. Template-based assembly of peptide units is one design option, but the use of two orthogonal self-assembly principles, oligonucleotide triple helix and a coiled coil protein domain formation have never been realized for de novo protein design. Here, we show the applicability of peptide–oligonucleotide conjugates for self-assembly of higher-ordered protein-like structures. The resulting nano-assemblies were characterized by ultraviolet-melting, gel electrophoresis, circular dichroism (CD) spectroscopy, small-angle X-ray scattering and transmission electron microscopy. These studies revealed the formation of the desired triple helix and coiled coil domains at low concentrations, while a dimer of trimers was dominating at high concentration. CD spectroscopy showed an extraordinarily high degree of α-helicity for the peptide moieties in the assemblies. The results validate the use of orthogonal self-assembly principles as a paradigm for de novo protein design. Peptide and oligonucleotide systems are known to self-assemble both in nature and artificial systems. Here, the authors combine both forms of self-assembly through the synthesis of peptideoligonucleotide conjugates and show formation of a three-helix structure that dimerises at higher concentrations.
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Affiliation(s)
- Chenguang Lou
- Department of Physics, Chemistry and Pharmacy, Biomolecular Nanoscale Engineering Center, University of Southern Denmark, Campusvej 55, Odense M 5230, Denmark
| | - Manuel C Martos-Maldonado
- Department of Chemistry, Biomolecular Nanoscale Engineering Center, University of Copenhagen, Thorvaldsensvej 40, Frederiksberg 1871, Denmark
| | - Charlotte S Madsen
- Department of Chemistry, Biomolecular Nanoscale Engineering Center, University of Copenhagen, Thorvaldsensvej 40, Frederiksberg 1871, Denmark
| | - Rasmus P Thomsen
- Biomolecular Nanoscale Engineering Center and Interdisciplinary Nanoscience Center (iNANO), University of Aarhus, Gustav Wieds Vej 14, Aarhus C 8000, Denmark
| | - Søren Roi Midtgaard
- Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, Copenhagen Ø 2100, Denmark
| | - Niels Johan Christensen
- Department of Chemistry, Biomolecular Nanoscale Engineering Center, University of Copenhagen, Thorvaldsensvej 40, Frederiksberg 1871, Denmark
| | - Jørgen Kjems
- Biomolecular Nanoscale Engineering Center and Interdisciplinary Nanoscience Center (iNANO), University of Aarhus, Gustav Wieds Vej 14, Aarhus C 8000, Denmark
| | - Peter W Thulstrup
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, Copenhagen Ø 2100, Denmark
| | - Jesper Wengel
- Department of Physics, Chemistry and Pharmacy, Biomolecular Nanoscale Engineering Center, University of Southern Denmark, Campusvej 55, Odense M 5230, Denmark
| | - Knud J Jensen
- Department of Chemistry, Biomolecular Nanoscale Engineering Center, University of Copenhagen, Thorvaldsensvej 40, Frederiksberg 1871, Denmark
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11
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Larsen AN, Sørensen KK, Johansen NT, Martel A, Kirkensgaard JJK, Jensen KJ, Arleth L, Midtgaard SR. Dimeric peptides with three different linkers self-assemble with phospholipids to form peptide nanodiscs that stabilize membrane proteins. Soft Matter 2016; 12:5937-5949. [PMID: 27306692 DOI: 10.1039/c6sm00495d] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Three dimers of the amphipathic α-helical peptide 18A have been synthesized with different interhelical linkers inserted between the two copies of 18A. The dimeric peptides were denoted 'beltides' where Beltide-1 refers to the 18A-dimer without a linker, Beltide-2 is the 18A-dimer with proline (Pro) as a linker and Beltide-3 is the 18A-dimer linked by two glycines (Gly-Gly). The self-assembly of the beltides with the phospholipid DMPC was studied with and without the incorporated membrane protein bacteriorhodopsin (bR) through a combination of coarse-grained MD simulations, size-exclusion chromatography (SEC), circular dichroism (CD) spectroscopy, small-angle scattering (SAS), static light scattering (SLS) and UV-Vis spectroscopy. For all three beltides, MD and combined small-angle X-ray and -neutron scattering were consistent with a disc structure composed by a phospholipid bilayer surrounded by a belt of peptides and with a total disc diameter of approximately 10 nm. CD confirmed that all three beltides were α-helical in the free form and with DMPC. However, as shown by SEC the different interhelical linkers clearly led to different properties of the beltides. Beltide-3, with the Gly-Gly linker, was very adaptable such that peptide nanodiscs could be formed for a broad range of different peptide to lipid stoichiometries and therefore also possible disc-sizes. On the other hand, both Beltide-2 with the Pro linker and Beltide-1 without a linker were less adaptable and would only form discs of certain peptide to lipid stoichiometries. SLS revealed that the structural stability of the formed peptide nanodiscs was also highly affected by the linkers and it was found that Beltide-1 gave more stable discs than the other two beltides. With respect to membrane protein stabilization, each of the three beltides in combination with DMPC stabilizes the seven-helix transmembrane protein bacteriorhodopsin significantly better than the detergent octyl glucoside, but no significant difference was observed between the three beltides. We conclude that adaptability, size, and structural stability can be tuned by changing the interhelical linker while maintaining the properties of the discs with respect to membrane protein stabilization.
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Affiliation(s)
| | | | | | | | | | - Knud J Jensen
- Department of Chemistry, University of Copenhagen, Denmark
| | - Lise Arleth
- Niels Bohr Institute, University of Copenhagen, Denmark.
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12
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Abstract
Structural and functional aspects of high-density lipoproteins have been studied for over half a century. Due to the plasticity of this highly complex system, new aspects continue to be discovered. Here, we present a structural study of the human Apolipoprotein A1 (ApoA1) and investigate the role of its N-terminal domain, the so-called globular domain of ApoA1, in discoidal complexes with phospholipids and increasing amounts of cholesterol. Using a combination of solution-based small-angle x-ray scattering (SAXS) and molecular constrained data modeling, we show that the ApoA1-1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC)-based particles are disk shaped with an elliptical cross section and composed by a central lipid bilayer surrounded by two stabilizing ApoA1 proteins. This structure is very similar to the particles formed in the so-called nanodisc system, which is based on N-terminal truncated ApoA1 protein. Although it is commonly agreed that the nanodisc is plain disk shaped, several more advanced structures have been proposed for the full-length ApoA1 in combination with POPC and cholesterol. This prompted us to make a detailed comparative study of the ApoA1 and nanodisc systems upon cholesterol uptake. Based on the presented SAXS analysis it is found that the N-terminal domains of ApoA1-POPC-cholesterol particles are not globular but instead an integrated part of the protein belt stabilizing the particles. Upon incorporation of increasing amounts of cholesterol, the presence of the N-terminal domain allows the bilayer thickness to increase while maintaining an overall flat bilayer structure. This is contrasted by the energetically more strained and less favorable lens shape required to fit the SAXS data from the N-terminal truncated nanodisc system upon cholesterol incorporation. This suggests that the N-terminal domain of ApoA1 actively participates in the stabilization of the ApoA1-POPC-cholesterol discoidal particle and allows for a more optimal lipid packing upon cholesterol uptake.
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Affiliation(s)
- Søren Roi Midtgaard
- X-Ray and Neutron Science, Niels Bohr Institute, University of Copenhagen, Denmark.
| | | | - Lise Arleth
- X-Ray and Neutron Science, Niels Bohr Institute, University of Copenhagen, Denmark
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13
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Habel J, Hansen M, Kynde S, Larsen N, Midtgaard SR, Jensen GV, Bomholt J, Ogbonna A, Almdal K, Schulz A, Hélix-Nielsen C. Aquaporin-Based Biomimetic Polymeric Membranes: Approaches and Challenges. Membranes (Basel) 2015; 5:307-51. [PMID: 26264033 PMCID: PMC4584284 DOI: 10.3390/membranes5030307] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 07/22/2015] [Indexed: 12/12/2022]
Abstract
In recent years, aquaporin biomimetic membranes (ABMs) for water separation have gained considerable interest. Although the first ABMs are commercially available, there are still many challenges associated with further ABM development. Here, we discuss the interplay of the main components of ABMs: aquaporin proteins (AQPs), block copolymers for AQP reconstitution, and polymer-based supporting structures. First, we briefly cover challenges and review recent developments in understanding the interplay between AQP and block copolymers. Second, we review some experimental characterization methods for investigating AQP incorporation including freeze-fracture transmission electron microscopy, fluorescence correlation spectroscopy, stopped-flow light scattering, and small-angle X-ray scattering. Third, we focus on recent efforts in embedding reconstituted AQPs in membrane designs that are based on conventional thin film interfacial polymerization techniques. Finally, we describe some new developments in interfacial polymerization using polyhedral oligomeric silsesquioxane cages for increasing the physical and chemical durability of thin film composite membranes.
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Affiliation(s)
- Joachim Habel
- Technical University of Denmark, Department of Environmental Engineering, Miljøvej, Building 113, 2800 Kgs. Lyngby, Denmark.
- Aquaporin A/S, Ole Maaløes Vej 3, 2200 Copenhagen, Denmark.
| | - Michael Hansen
- University of Copenhagen, Department of Plant and Environmental Sciences, Thorvaldsensvej 40, 1871 Frederiksberg, Denmark.
| | - Søren Kynde
- University of Copenhagen, Copenhagen Biocenter, Ole Maaløes Vej 5, 2200 Copenhagen, Denmark.
| | - Nanna Larsen
- University of Copenhagen, Niels Bohr Institute, Hans Christian Ørsted building D, Universitetsparken, 5, 2100 Copenhagen, Denmark.
| | - Søren Roi Midtgaard
- University of Copenhagen, Copenhagen Biocenter, Ole Maaløes Vej 5, 2200 Copenhagen, Denmark.
| | | | - Julie Bomholt
- Aquaporin A/S, Ole Maaløes Vej 3, 2200 Copenhagen, Denmark.
| | - Anayo Ogbonna
- Aquaporin A/S, Ole Maaløes Vej 3, 2200 Copenhagen, Denmark.
| | - Kristoffer Almdal
- Technical University of Denmark, Department of Micro- and Nanotechnology, Produktionstorvet, Building 423, 2800 Kgs. Lyngby.
| | - Alexander Schulz
- University of Copenhagen, Department of Plant and Environmental Sciences, Thorvaldsensvej 40, 1871 Frederiksberg, Denmark.
| | - Claus Hélix-Nielsen
- Technical University of Denmark, Department of Environmental Engineering, Miljøvej, Building 113, 2800 Kgs. Lyngby, Denmark.
- Aquaporin A/S, Ole Maaløes Vej 3, 2200 Copenhagen, Denmark.
- University of Maribor, Laboratory for Water Biophysics and Membrane Processes, Faculty of Chemistry and Chemical Engineering, Smetanova ulica 17, 2000 Maribor, Slovenia.
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14
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Wong JEMM, Midtgaard SR, Gysel K, Thygesen MB, Sørensen KK, Jensen KJ, Stougaard J, Thirup S, Blaise M. An intermolecular binding mechanism involving multiple LysM domains mediates carbohydrate recognition by an endopeptidase. Acta Crystallogr D Biol Crystallogr 2015; 71:592-605. [PMID: 25760608 PMCID: PMC4356369 DOI: 10.1107/s139900471402793x] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 12/22/2014] [Indexed: 11/10/2022]
Abstract
LysM domains, which are frequently present as repetitive entities in both bacterial and plant proteins, are known to interact with carbohydrates containing N-acetylglucosamine (GlcNAc) moieties, such as chitin and peptidoglycan. In bacteria, the functional significance of the involvement of multiple LysM domains in substrate binding has so far lacked support from high-resolution structures of ligand-bound complexes. Here, a structural study of the Thermus thermophilus NlpC/P60 endopeptidase containing two LysM domains is presented. The crystal structure and small-angle X-ray scattering solution studies of this endopeptidase revealed the presence of a homodimer. The structure of the two LysM domains co-crystallized with N-acetyl-chitohexaose revealed a new intermolecular binding mode that may explain the differential interaction between LysM domains and short or long chitin oligomers. By combining the structural information with the three-dimensional model of peptidoglycan, a model suggesting how protein dimerization enhances the recognition of peptidoglycan is proposed.
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Affiliation(s)
- Jaslyn E. M. M. Wong
- Centre for Carbohydrate Recognition and Signalling, Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10C, 8000 Aarhus, Denmark
| | - Søren Roi Midtgaard
- Niels Bohr Institute, Faculty of Science, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Kira Gysel
- Centre for Carbohydrate Recognition and Signalling, Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10C, 8000 Aarhus, Denmark
| | - Mikkel B. Thygesen
- Centre for Carbohydrate Recognition and Signalling, Department of Chemistry, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Kasper K. Sørensen
- Centre for Carbohydrate Recognition and Signalling, Department of Chemistry, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Knud J. Jensen
- Centre for Carbohydrate Recognition and Signalling, Department of Chemistry, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Jens Stougaard
- Centre for Carbohydrate Recognition and Signalling, Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10C, 8000 Aarhus, Denmark
| | - Søren Thirup
- Centre for Carbohydrate Recognition and Signalling, Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10C, 8000 Aarhus, Denmark
| | - Mickaël Blaise
- Centre for Carbohydrate Recognition and Signalling, Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10C, 8000 Aarhus, Denmark
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15
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Habel J, Ogbonna A, Larsen N, Cherré S, Kynde S, Midtgaard SR, Kinoshita K, Krabbe S, Jensen GV, Hansen JS, Almdal K, Hèlix-Nielsen C. Selecting analytical tools for characterization of polymersomes in aqueous solution. RSC Adv 2015. [DOI: 10.1039/c5ra16403f] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
We present 17 techniques to analyze polymersomes, in terms of their size, bilayer properties, elastic properties or surface charge.
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Affiliation(s)
- Joachim Habel
- Technical University of Denmark
- Department of Environmental Engineering
- 2800 Kgs. Lyngby
- Denmark
- Aquaporin A/S
| | | | - Nanna Larsen
- University of Copenhagen
- Copenhagen Biocenter
- 2200 Copenhagen
- Denmark
| | - Solène Cherré
- Technical University of Denmark
- Department of Micro- and Nanotechnology
- 2800 Kgs. Lyngby
- Denmark
| | - Søren Kynde
- University of Copenhagen
- Niels Bohr Institute
- 2100 Copenhagen
- Denmark
| | | | - Koji Kinoshita
- University of Southern Denmark
- Department of Physics
- Chemistry and Pharmacy
- 5230 Odense
- Denmark
| | - Simon Krabbe
- University of Copenhagen
- Department of Biology
- 2100 Copenhagen
- Denmark
| | | | | | - Kristoffer Almdal
- Technical University of Denmark
- Department of Micro- and Nanotechnology
- 2800 Kgs. Lyngby
- Denmark
| | - Claus Hèlix-Nielsen
- Technical University of Denmark
- Department of Environmental Engineering
- 2800 Kgs. Lyngby
- Denmark
- Aquaporin A/S
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16
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Midtgaard SR, Pedersen MC, Kirkensgaard JJK, Sørensen KK, Mortensen K, Jensen KJ, Arleth L. Self-assembling peptides form nanodiscs that stabilize membrane proteins. Soft Matter 2014; 10:738-752. [PMID: 24651399 DOI: 10.1039/c3sm51727f] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
New methods to handle membrane bound proteins, e.g. G-protein coupled receptors (GPCRs), are highly desirable. Recently, apoliprotein A1 (ApoA1) based lipoprotein particles have emerged as a new platform for studying membrane proteins, and it has been shown that they can self-assemble in combination with phospholipids to form discoidal shaped particles that can stabilize membrane proteins. In the present study, we have investigated an ApoA1 mimetic peptide with respect to its solution structure when in complex with phospholipids. This was achieved using a powerful combination of small-angle X-ray scattering (SAXS) and small-angle neutron scattering (SANS) supported by coarse-grained molecular dynamics simulations. The detailed structure of the discs was determined in unprecedented detail and it was found that they adopt a discoidal structure very similar to the ApoA1 based nanodiscs. We furthermore show that, like the ApoA1 and derived nanodiscs, these peptide discs can accommodate and stabilize a membrane protein. Finally, we exploit their dynamic properties and show that the 18A discs may be used for transferring membrane proteins and associated phospholipids directly and gently into phospholipid nanodiscs.
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17
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Kynde SAR, Skar-Gislinge N, Pedersen MC, Midtgaard SR, Simonsen JB, Schweins R, Mortensen K, Arleth L. Small-angle scattering gives direct structural information about a membrane protein inside a lipid environment. ACTA ACUST UNITED AC 2014; 70:371-83. [PMID: 24531471 DOI: 10.1107/s1399004713028344] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Accepted: 10/15/2013] [Indexed: 12/11/2022]
Abstract
Monomeric bacteriorhodopsin (bR) reconstituted into POPC/POPG-containing nanodiscs was investigated by combined small-angle neutron and X-ray scattering. A novel hybrid approach to small-angle scattering data analysis was developed. In combination, these provided direct structural insight into membrane-protein localization in the nanodisc and into the protein-lipid interactions. It was found that bR is laterally decentred in the plane of the disc and is slightly tilted in the phospholipid bilayer. The thickness of the bilayer is reduced in response to the incorporation of bR. The observed tilt of bR is in good accordance with previously performed theoretical predictions and computer simulations based on the bR crystal structure. The result is a significant and essential step on the way to developing a general small-angle scattering-based method for determining the low-resolution structures of membrane proteins in physiologically relevant environments.
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Affiliation(s)
- Søren A R Kynde
- Structural Biophysics, Niels Bohr Institute, Faculty of Science, University of Copenhagen, Denmark
| | - Nicholas Skar-Gislinge
- Structural Biophysics, Niels Bohr Institute, Faculty of Science, University of Copenhagen, Denmark
| | - Martin Cramer Pedersen
- Structural Biophysics, Niels Bohr Institute, Faculty of Science, University of Copenhagen, Denmark
| | - Søren Roi Midtgaard
- Structural Biophysics, Niels Bohr Institute, Faculty of Science, University of Copenhagen, Denmark
| | - Jens Baek Simonsen
- Structural Biophysics, Niels Bohr Institute, Faculty of Science, University of Copenhagen, Denmark
| | | | - Kell Mortensen
- Structural Biophysics, Niels Bohr Institute, Faculty of Science, University of Copenhagen, Denmark
| | - Lise Arleth
- Structural Biophysics, Niels Bohr Institute, Faculty of Science, University of Copenhagen, Denmark
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18
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Blaise M, Alsarraf HMAB, Wong JEMM, Midtgaard SR, Laroche F, Schack L, Spaink H, Stougaard J, Thirup S. Crystal structure of the TLDc domain of oxidation resistance protein 2 from zebrafish. Proteins 2012; 80:1694-8. [PMID: 22434723 DOI: 10.1002/prot.24050] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Revised: 01/23/2012] [Accepted: 01/25/2012] [Indexed: 11/10/2022]
Abstract
The oxidation resistance proteins (OXR) help to protect eukaryotes from reactive oxygen species. The sole C-terminal domain of the OXR, named TLDc is sufficient to perform this function. However, the mechanism by which oxidation resistance occurs is poorly understood. We present here the crystal structure of the TLDc domain of the oxidation resistance protein 2 from zebrafish. The structure was determined by X-ray crystallography to atomic resolution (0.97Å) and adopts an overall globular shape. Two antiparallel β-sheets form a central β-sandwich, surrounded by two helices and two one-turn helices. The fold shares low structural similarity to known structures.
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Affiliation(s)
- Mickaël Blaise
- Department of Molecular Biology and Genetics, Centre for Carbohydrate Recognition and Signalling, Aarhus University, Aarhus, Denmark.
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