1
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Dey A, Patil A, Arumugam S, Maiti S. Single-Molecule Maps of Membrane Insertion by Amyloid-β Oligomers Predict Their Toxicity. J Phys Chem Lett 2024; 15:6292-6298. [PMID: 38855822 DOI: 10.1021/acs.jpclett.4c01048] [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: 06/11/2024]
Abstract
The interaction of small Amyloid-β (Aβ) oligomers with the lipid membrane is an important component of the pathomechanism of Alzheimer's disease (AD). However, oligomers are heterogeneous in size. How each type of oligomer incorporates into the membrane, and how that relates to their toxicity, is unknown. Here, we employ a single molecule technique called Q-SLIP (Quencher-induced Step Length Increase in Photobleaching) to measure the membrane insertion of each monomeric unit of individual oligomers of Aβ42, Aβ40, and Aβ40-F19-Cyclohexyl alanine (Aβ40-F19Cha), and correlate it with their toxicity. We observe that the N-terminus of Aβ42 inserts close to the center of the bilayer, the less toxic Aβ40 inserts to a shallower depth, and the least toxic Aβ40-F19Cha has no specific distribution. This oligomer-specific map provides a mechanistic representation of membrane-mediated Aβ toxicity and should be a valuable tool for AD research.
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Affiliation(s)
- Arpan Dey
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai 400005, India
| | - Abhishek Patil
- Monash Biomedicine Discovery Institute, Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton/Melbourne, VIC 3800, Australia
| | - Senthil Arumugam
- Monash Biomedicine Discovery Institute, Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton/Melbourne, VIC 3800, Australia
- European Molecular Biological Laboratory Australia (EMBL Australia), Monash University, Clayton/Melbourne, VIC 3800, Australia
| | - Sudipta Maiti
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai 400005, India
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2
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Gómez-Castro CZ, Quintanar L, Vela A. An N-terminal acidic β-sheet domain is responsible for the metal-accumulation properties of amyloid-β protofibrils: a molecular dynamics study. J Biol Inorg Chem 2024; 29:407-425. [PMID: 38811408 PMCID: PMC11186886 DOI: 10.1007/s00775-024-02061-1] [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: 12/20/2023] [Accepted: 04/10/2024] [Indexed: 05/31/2024]
Abstract
The influence of metal ions on the structure of amyloid- β (Aβ) protofibril models was studied through molecular dynamics to explore the molecular mechanisms underlying metal-induced Aβ aggregation relevant in Alzheimer's disease (AD). The models included 36-, 48-, and 188-mers of the Aβ42 sequence and two disease-modifying variants. Primary structural effects were observed at the N-terminal domain, as it became susceptible to the presence of cations. Specially when β-sheets predominate, this motif orients N-terminal acidic residues toward one single face of the β-sheet, resulting in the formation of an acidic region that attracts cations from the media and promotes the folding of the N-terminal region, with implications in amyloid aggregation. The molecular phenotype of the protofibril models based on Aβ variants shows that the AD-causative D7N mutation promotes the formation of N-terminal β-sheets and accumulates more Zn2+, in contrast to the non-amyloidogenic rodent sequence that hinders the β-sheets and is more selective for Na+ over Zn2+ cations. It is proposed that forming an acidic β-sheet domain and accumulating cations is a plausible molecular mechanism connecting the elevated affinity and concentration of metals in Aβ fibrils to their high content of β-sheet structure at the N-terminal sequence.
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Affiliation(s)
- Carlos Z Gómez-Castro
- Conahcyt-Universidad Autónoma del Estado de Hidalgo, Km 4.5 Carr. Pachuca-Tulancingo, Mineral de La Reforma, 42184, Hidalgo, Mexico.
| | - Liliana Quintanar
- Department of Chemistry, Cinvestav, Av. Instituto Politécnico Nacional 2508, CDMX, San Pedro Zacatenco, 07360, Gustavo A. Madero, Mexico.
| | - Alberto Vela
- Department of Chemistry, Cinvestav, Av. Instituto Politécnico Nacional 2508, CDMX, San Pedro Zacatenco, 07360, Gustavo A. Madero, Mexico.
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3
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Dey A, Verma A, Bhaskar U, Sarkar B, Kallianpur M, Vishvakarma V, Das AK, Garai K, Mukherjee O, Ishii K, Tahara T, Maiti S. A Toxicogenic Interaction between Intracellular Amyloid-β and Apolipoprotein-E. ACS Chem Neurosci 2024; 15:1265-1275. [PMID: 38421952 DOI: 10.1021/acschemneuro.4c00048] [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] [Indexed: 03/02/2024] Open
Abstract
Alzheimer's disease (AD) is associated with the aggregation of amyloid β (Aβ) and tau proteins. Why ApoE variants are significant genetic risk factors remains a major unsolved puzzle in understanding AD, although intracellular interactions with ApoE are suspected to play a role. Here, we show that specific changes in the fluorescence lifetime of fluorescently tagged small Aβ oligomers in rat brain cells correlate with the cellular ApoE content. An inhibitor of the Aβ-ApoE interaction suppresses these changes and concomitantly reduces Aβ toxicity in a dose-dependent manner. Single-molecule techniques show changes both in the conformation and in the stoichiometry of the oligomers. Neural stem cells derived from hiPSCs of Alzheimer's patients also exhibit these fluorescence lifetime changes. We infer that intracellular interaction with ApoE modifies the N-terminus of the Aβ oligomers, inducing changes in their stoichiometry, membrane affinity, and toxicity. These changes can be directly imaged in live cells and can potentially be used as a rapid and quantitative cellular assay for AD drug discovery.
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Affiliation(s)
- Arpan Dey
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai 400005, India
| | - Aditi Verma
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai 400005, India
| | - Uchit Bhaskar
- Institute of Stem Cell Science and Regenerative Medicine, Bangalore 560065, India
| | - Bidyut Sarkar
- Molecular Spectroscopy Laboratory, RIKEN, Wako, Saitama 3510198, Japan
| | - Mamata Kallianpur
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai 400005, India
| | - Vicky Vishvakarma
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai 400005, India
| | - Anand Kant Das
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai 400005, India
| | - Kanchan Garai
- Tata Institute of Fundamental Research, Hyderabad 500107, India
| | - Odity Mukherjee
- Institute of Stem Cell Science and Regenerative Medicine, Bangalore 560065, India
| | - Kunihiko Ishii
- Molecular Spectroscopy Laboratory, RIKEN, Wako, Saitama 3510198, Japan
| | - Tahei Tahara
- Molecular Spectroscopy Laboratory, RIKEN, Wako, Saitama 3510198, Japan
| | - Sudipta Maiti
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai 400005, India
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4
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Scheidt HA, Korn A, Schwarze B, Krueger M, Huster D. Conformation of Pyroglutamated Amyloid β (3-40) and (11-40) Fibrils - Extended or Hairpin? J Phys Chem B 2024; 128:1647-1655. [PMID: 38334278 PMCID: PMC10895672 DOI: 10.1021/acs.jpcb.3c07285] [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: 11/02/2023] [Revised: 01/04/2024] [Accepted: 01/30/2024] [Indexed: 02/10/2024]
Abstract
Amyloid β (Aβ) is a hallmark protein of Alzheimer's disease. One physiologically important Aβ variant is formed by initial N-terminal truncation at a glutamic acid position (either E3 or E11), which is subsequently cyclized to a pyroglutamate (either pE3 or pE11). Both forms have been found in high concentrations in the core of amyloid plaques and are likely of high importance in the pathology of Alzheimer's disease. However, the molecular structure of the fibrils of these variants is not entirely clear. Solid-state NMR spectroscopy studies have reported a molecular contact between Gly25 and Ile31, which would disagree with the conventional hairpin model of wildtype (WT-)Aβ1-40 fibrils, most often described in the literature. We investigated the conformation of the monomeric unit of pE3-Aβ3-40 and pE11-Aβ11-40 (and for comparison also wildtype (WT)-Aβ1-40) fibrils to find out whether the hairpin or a newly suggested extended structure dominates the structure of the Aβ monomers in these fibrils. To this end, solid-state NMR spectroscopy was applied probing the inter-residual contacts between Phe19/Leu34, Ala21/Leu34, and especially Gly25/Ile31 using suitable isotopic labeling schemes. In the second part, the flexible turn of the Aβ40 peptides was replaced by a (3-(3-aminomethyl)phenylazo)phenylacetic acid (AMPP)-based photoswitch, which can predefine the peptide conformation to either an extended (trans) or hairpin (cis) conformation. This enables simultaneous spectroscopic assessment of the conformation of the AMPP-photoswitch, allowing in situ structural investigations during fibrillation in contrast to structural techniques such as NMR spectroscopy or cryo-EM, which can only be applied to stable conformers. Both methods confirm an extended structure for the peptidic monomers in fibrils of all investigated Aβ variants. Especially the Gly25/Ile31 contact is a decisive indicator for the extended structure along with the characteristic absorption spectra of trans-AMPP-Aβ.
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Affiliation(s)
- Holger A. Scheidt
- Institute
for Medical Physics and Biophysics, Leipzig
University Härtelstr. 16/18, D-04107 Leipzig, Germany
| | - Alexander Korn
- Institute
for Medical Physics and Biophysics, Leipzig
University Härtelstr. 16/18, D-04107 Leipzig, Germany
| | - Benedikt Schwarze
- Institute
for Medical Physics and Biophysics, Leipzig
University Härtelstr. 16/18, D-04107 Leipzig, Germany
| | - Martin Krueger
- Institute
of Anatomy, Leipzig University, Liebigstr. 13, 04103 Leipzig, Germany
| | - Daniel Huster
- Institute
for Medical Physics and Biophysics, Leipzig
University Härtelstr. 16/18, D-04107 Leipzig, Germany
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5
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Yokoyama K, Barbour E, Hirschkind R, Martinez Hernandez B, Hausrath K, Lam T. Protein Corona Formation and Aggregation of Amyloid β 1-40-Coated Gold Nanocolloids. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:1728-1746. [PMID: 38194428 DOI: 10.1021/acs.langmuir.3c02923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2024]
Abstract
Amyloid fibrillogenesis is a pathogenic protein aggregation process that occurs through a highly ordered process of protein-protein interactions. To better understand the protein-protein interactions involved in amyloid fibril formation, we formed nanogold colloid aggregates by stepwise additions of ∼2 nmol of amyloid β 1-40 peptide (Aβ1-40) at pH ∼3.7 and ∼25 °C. The processes of protein corona formation and building of gold colloid [diameters (d) of 20 and 80 nm] aggregates were confirmed by a red-shift of the surface plasmon resonance (SPR) band, λpeak, as the number of Aβ1-40 peptides [N(Aβ1-40)] increased. The normalized red-shift of λpeak, Δλ, was correlated with the degree of protein aggregation, and this process was approximated as the adsorption isotherm explained by the Langmuir-Freundlich model. As the coverage fraction (θ) was analyzed as a function of ϕ, which is the N(Aβ1-40) per total surface area of nanogold colloids available for adsorption, the parameters for explaining the Langmuir-Freundlich model were in good agreement for both 20 and 80 nm gold, indicating that ϕ could define the stage of the aggregation process. Surface-enhanced Raman scattering (SERS) imaging was conducted at designated values of ϕ and suggested that a protein-gold surface interaction during the initial adsorption stage may be dependent on the nanosize. The 20 nm gold case seems to prefer a relatively smaller contacting section, such as a -C-N or C═C bond, but a plane of the benzene ring may play a significant role for 80 nm gold. Regardless of the size of the particles, the β-sheet and random coil conformations were considered to be used to form gold colloid aggregates. The methodology developed in this study allows for new insights into protein-protein interactions at distinct stages of aggregation.
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Affiliation(s)
- Kazushige Yokoyama
- Department of Chemistry, The State University of New York Geneseo College, 1 College Circle, Geneseo, New York 14454, United States
| | - Eli Barbour
- Department of Chemistry, The State University of New York Geneseo College, 1 College Circle, Geneseo, New York 14454, United States
| | - Rachel Hirschkind
- Department of Chemistry, The State University of New York Geneseo College, 1 College Circle, Geneseo, New York 14454, United States
| | - Bryan Martinez Hernandez
- Department of Chemistry, The State University of New York Geneseo College, 1 College Circle, Geneseo, New York 14454, United States
| | - Kaylee Hausrath
- Department of Chemistry, The State University of New York Geneseo College, 1 College Circle, Geneseo, New York 14454, United States
| | - Theresa Lam
- Department of Chemistry, The State University of New York Geneseo College, 1 College Circle, Geneseo, New York 14454, United States
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6
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Yeh CT, Chang HW, Hsu WH, Huang SJ, Wu MH, Tu LH, Lee MC, Chan JCC. Beta Amyloid Oligomers with Higher Cytotoxicity have Higher Sidechain Dynamics. Chemistry 2023; 29:e202301879. [PMID: 37706579 DOI: 10.1002/chem.202301879] [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: 06/13/2023] [Indexed: 09/15/2023]
Abstract
The underlying biophysical principle governing the cytotoxicity of the oligomeric aggregates of β-amyloid (Aβ) peptides has long been an enigma. Here we show that the size of Aβ40 oligomers can be actively controlled by incubating the peptides in reverse micelles. Our approach allowed for the first time a detailed comparison of the structures and dynamics of two Aβ40 oligomers of different sizes, viz., 10 and 23 nm, by solid-state NMR. From the chemical shift data, we infer that the conformation and/or the chemical environments of the residues from K16 to K28 are different between the 10-nm and 23-nm oligomers. We find that the 10-nm oligomers are more cytotoxic, and the molecular motion of the sidechain of its charged residue K16 is more dynamic. Interestingly, the residue A21 exhibits unusually high structural rigidity. Our data raise an interesting possibility that the cytotoxicity of Aβ40 oligomers could also be correlated to the motional dynamics of the sidechains.
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Affiliation(s)
- Chen-Tsen Yeh
- Department of Chemistry, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 10617, Taiwan
| | - Han-Wen Chang
- Department of Chemistry, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 10617, Taiwan
| | - Wen-Hsin Hsu
- Department of Chemistry, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 10617, Taiwan
| | - Shing-Jong Huang
- Instrumentation Center, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 10617, Taiwan
| | - Meng-Hsin Wu
- Department of Chemistry, National Taiwan Normal University, No. 88, Section 4, Ting-Chow Road, Taipei, 11677, Taiwan
| | - Ling-Hsien Tu
- Department of Chemistry, National Taiwan Normal University, No. 88, Section 4, Ting-Chow Road, Taipei, 11677, Taiwan
| | - Ming-Che Lee
- Department of Chemistry, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 10617, Taiwan
| | - Jerry Chun Chung Chan
- Department of Chemistry, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 10617, Taiwan
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7
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Arunachalam V, Sharma K, Mote KR, Madhu PK. Asynchronising five-fold symmetry sequence for better homonuclear polarisation transfer in magic-angle-spinning solid-state NMR. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2023; 124:101858. [PMID: 36796278 DOI: 10.1016/j.ssnmr.2023.101858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Revised: 01/28/2023] [Accepted: 01/30/2023] [Indexed: 06/18/2023]
Abstract
Recoupling, decoupling, and multidimensional correlation experiments in magic-angle-spinning (MAS) solid-state NMR can be designed by exploiting the symmetry of internal spin interactions. One such scheme, namely, C521, and its supercycled version SPC521, notated as a five-fold symmetry sequence, is widely used for double-quantum dipole-dipole recoupling. Such schemes are generally rotor synchronised by design. We demonstrate an asynchronous implementation of the SPC521 sequence leading to higher double-quantum homonuclear polarisation transfer efficiency compared to the normal synchronous implementation. Rotor-synchronisation is broken in two different ways: lengthening the duration of one of the pulses, denoted as pulse-width variation (PWV), and mismatching the MAS frequency denoted as MAS variation (MASV). The application of this asynchronous sequence is shown on three different samples, namely, U-13C-alanine and 1,4-13C-labelled ammonium phthalate which include 13Cα-13Cβ, 13Cα-13Co, and 13Co-13Co spin systems, and adenosine 5'- triphosphate disodium salt trihydrate (ATP⋅3H2O). We show that the asynchronous version performs better for spin pairs with small dipole-dipole couplings and large chemical-shift anisotropies, for example, 13Co-13Co. Simulations and experiments are shown to corroborate the results.
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Affiliation(s)
- Vaishali Arunachalam
- Tata Institute of Fundamental Research Hyderabad, 36/P Gopanpally Village, Ranga Reddy District, Hyderabad, 500046, India.
| | - Kshama Sharma
- Tata Institute of Fundamental Research Hyderabad, 36/P Gopanpally Village, Ranga Reddy District, Hyderabad, 500046, India.
| | - Kaustubh R Mote
- Tata Institute of Fundamental Research Hyderabad, 36/P Gopanpally Village, Ranga Reddy District, Hyderabad, 500046, India.
| | - P K Madhu
- Tata Institute of Fundamental Research Hyderabad, 36/P Gopanpally Village, Ranga Reddy District, Hyderabad, 500046, India.
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8
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Abstract
Perturbation of cell membranes by amyloid β (Ab) peptide oligomers is one possible mechanism of cytotoxicity in Alzheimer's disease, but the structure of such Ab-membrane complexes is unknown. Here we examine the stability of several putative structures by implicit membrane and all-atom molecular dynamics simulations. The structures include (a) a variety of models proposed by other researchers in the past, (b) a heptameric β barrel determined by grafting the Ab sequence onto α-hemolysin, (c) a similar structure with modified strand orientation and turn location based on an experimental β-hairpin structure, (d) oligomers inserting C-terminal β hairpins into one leaflet of the bilayer, (e) oligomers forming parallel C-terminal β barrels, and (f) a helical hexamer made of C-terminal fragments. The α-hemolysin-grafted structure and its alternately oriented variant are stable in the membrane and form an aqueous pore. In contrast, the C-terminal parallel barrels are not stable, presumably due to excessive hydrophobicity of their inner surface. The helical hexamer also failed to stabilize an aqueous pore for the same reason. The C-terminal hairpin-inserting structures remain stably inserted but, again, do not form an aqueous pore. Our results suggest that only β-barrels inserting a combination of C-terminal and other residues can form stable aqueous pores.
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Affiliation(s)
- Aliasghar Sepehri
- Department of Chemistry, City College of New York, CUNY, 160 Convent Avenue, New York, New York10031, United States
| | - Themis Lazaridis
- Department of Chemistry, City College of New York, CUNY, 160 Convent Avenue, New York, New York10031, United States.,Graduate Programs in Chemistry, Biochemistry, and Physics, The Graduate Center, City University of New York, 365 Fifth Avenue, New York, New York10016, United States
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9
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Abstract
It is known that oligomers of amyloid-β (Aβ) peptide are associated with Alzheimer's disease. Aβ has two isoforms: Aβ40 and Aβ42. Although the difference between Aβ40 and Aβ42 is only two additional C-terminal residues, Aβ42 aggregates much faster than Aβ40. It is unknown what role the C-terminal two residues play in accelerating aggregation. Since Aβ42 is more toxic than Aβ40, its oligomerization process needs to be clarified. Moreover, clarifying the differences between the oligomerization processes of Aβ40 and Aβ42 is essential to elucidate the key factors of oligomerization. Therefore, to investigate the dimerization process, which is the early oligomerization process, Hamiltonian replica-permutation molecular dynamics simulations were performed for Aβ40 and Aβ42. We identified a key residue, Arg5, for the Aβ42 dimerization. The two additional residues in Aβ42 allow the C-terminus to form contact with Arg5 because of the electrostatic attraction between them, and this contact stabilizes the β-hairpin. This β-hairpin promotes dimer formation through the intermolecular β-bridges. Thus, we examined the effects of amino acid substitutions of Arg5, thereby confirming that the mutations remarkably suppressed the aggregation of Aβ42. Moreover, the mutations of Arg5 suppressed the Aβ40 aggregation. It was found by analyzing the simulations that Arg5 is important for Aβ40 to form intermolecular contacts. Thus, it was clarified that the role of Arg5 in the oligomerization process varies due to the two additional C-terminal residues.
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Affiliation(s)
- Satoru
G. Itoh
- Institute
for Molecular Science, National Institutes
of Natural Sciences, Okazaki, Aichi 444-8787, Japan,Exploratory
Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan,Department
of Structural Molecular Science, SOKENDAI
(The Graduate University for Advanced Studies), Okazaki, Aichi 444-8787, Japan
| | - Maho Yagi-Utsumi
- Institute
for Molecular Science, National Institutes
of Natural Sciences, Okazaki, Aichi 444-8787, Japan,Exploratory
Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan,Department
of Functional Molecular Science, SOKENDAI
(The Graduate University for Advanced Studies), Okazaki, Aichi 444-8787, Japan,Graduate
School of Pharmaceutical Sciences, Nagoya
City University, Nagoya, Aichi 465-8603, Japan
| | - Koichi Kato
- Institute
for Molecular Science, National Institutes
of Natural Sciences, Okazaki, Aichi 444-8787, Japan,Exploratory
Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan,Department
of Functional Molecular Science, SOKENDAI
(The Graduate University for Advanced Studies), Okazaki, Aichi 444-8787, Japan,Graduate
School of Pharmaceutical Sciences, Nagoya
City University, Nagoya, Aichi 465-8603, Japan
| | - Hisashi Okumura
- Institute
for Molecular Science, National Institutes
of Natural Sciences, Okazaki, Aichi 444-8787, Japan,Exploratory
Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan,Department
of Structural Molecular Science, SOKENDAI
(The Graduate University for Advanced Studies), Okazaki, Aichi 444-8787, Japan,
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10
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Wu Y, Huang S, Wu M, Tu L, Lee M, Chan JCC. Aβ
42
oligomers can seed the fibrillization of Aβ
40
peptides. J CHIN CHEM SOC-TAIP 2022. [DOI: 10.1002/jccs.202200136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Yi‐Shan Wu
- Department of Chemistry National Taiwan University Taipei Taiwan
| | | | - Meng‐Hsin Wu
- Department of Chemistry National Taiwan Normal University Taipei Taiwan
| | - Ling‐Hsien Tu
- Department of Chemistry National Taiwan Normal University Taipei Taiwan
| | - Ming‐Che Lee
- Department of Chemistry National Taiwan University Taipei Taiwan
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11
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Klose D, Vemulapalli SPB, Richman M, Rudnick S, Aisha V, Abayev M, Chemerovski M, Shviro M, Zitoun D, Majer K, Wili N, Goobes G, Griesinger C, Jeschke G, Rahimipour S. Cu 2+-Induced self-assembly and amyloid formation of a cyclic D,L-α-peptide: structure and function. Phys Chem Chem Phys 2022; 24:6699-6715. [PMID: 35234757 DOI: 10.1039/d1cp05415e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In a wide spectrum of neurodegenerative diseases, self-assembly of pathogenic proteins to cytotoxic intermediates is accelerated by the presence of metal ions such as Cu2+. Only low concentrations of these early transient oligomeric intermediates are present in a mixture of species during fibril formation, and hence information on the extent of structuring of these oligomers is still largely unknown. Here, we investigate dimers as the first intermediates in the Cu2+-driven aggregation of a cyclic D,L-α-peptide architecture. The unique structural and functional properties of this model system recapitulate the self-assembling properties of amyloidogenic proteins including β-sheet conformation and cross-interaction with pathogenic amyloids. We show that a histidine-rich cyclic D,L-α-octapeptide binds Cu2+ with high affinity and selectivity to generate amyloid-like cross-β-sheet structures. By taking advantage of backbone amide methylation to arrest the self-assembly at the dimeric stage, we obtain structural information and characterize the degree of local order for the dimer. We found that, while catalytic amounts of Cu2+ promote aggregation of the peptide to fibrillar structures, higher concentrations dose-dependently reduce fibrillization and lead to formation of spherical particles, showing self-assembly to different polymorphs. For the initial self-assembly step to the dimers, we found that Cu2+ is coordinated on average by two histidines, similar to self-assembled peptides, indicating that a similar binding interface is perpetuated during Cu2+-driven oligomerization. The dimer itself is found in heterogeneous conformations that undergo dynamic exchange, leading to the formation of different polymorphs at the initial stage of the aggregation process.
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Affiliation(s)
- Daniel Klose
- Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich, Switzerland.
| | - Sahithya Phani Babu Vemulapalli
- NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany. .,Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, 26129 Oldenburg, Germany
| | - Michal Richman
- Department of Chemistry, Bar-Ilan University, Ramat-Gan 5290002, Israel.
| | - Safra Rudnick
- Department of Chemistry, Bar-Ilan University, Ramat-Gan 5290002, Israel. .,Bar-Ilan Institute for Technology and Advanced Materials (BINA), Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Vered Aisha
- Department of Chemistry, Bar-Ilan University, Ramat-Gan 5290002, Israel.
| | - Meital Abayev
- Department of Chemistry, Bar-Ilan University, Ramat-Gan 5290002, Israel.
| | - Marina Chemerovski
- Department of Chemistry, Bar-Ilan University, Ramat-Gan 5290002, Israel.
| | - Meital Shviro
- Department of Chemistry, Bar-Ilan University, Ramat-Gan 5290002, Israel. .,Bar-Ilan Institute for Technology and Advanced Materials (BINA), Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - David Zitoun
- Department of Chemistry, Bar-Ilan University, Ramat-Gan 5290002, Israel. .,Bar-Ilan Institute for Technology and Advanced Materials (BINA), Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Katharina Majer
- Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich, Switzerland.
| | - Nino Wili
- Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich, Switzerland.
| | - Gil Goobes
- Department of Chemistry, Bar-Ilan University, Ramat-Gan 5290002, Israel.
| | - Christian Griesinger
- NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany.
| | - Gunnar Jeschke
- Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich, Switzerland.
| | - Shai Rahimipour
- Department of Chemistry, Bar-Ilan University, Ramat-Gan 5290002, Israel.
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12
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Tachi Y, Itoh SG, Okumura H. Molecular dynamics simulations of amyloid-β peptides in heterogeneous environments. Biophys Physicobiol 2022; 19:1-18. [PMID: 35666692 PMCID: PMC9135617 DOI: 10.2142/biophysico.bppb-v19.0010] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 03/31/2022] [Indexed: 12/01/2022] Open
Affiliation(s)
- Yuhei Tachi
- Department of Physics, Graduate school of Science, Nagoya University
| | - Satoru G. Itoh
- Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences
| | - Hisashi Okumura
- Institute for Molecular Science, National Institutes of Natural Sciences
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13
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Chang HW, Ma HI, Wu YS, Lee MC, Chung-Yueh Yuan E, Huang SJ, Cheng YS, Wu MH, Tu LH, Chan JCC. Site specific NMR characterization of abeta-40 oligomers cross seeded by abeta-42 oligomers. Chem Sci 2022; 13:8526-8535. [PMID: 35974768 PMCID: PMC9337746 DOI: 10.1039/d2sc01555b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 06/12/2022] [Indexed: 12/18/2022] Open
Abstract
Extracellular accumulation of β amyloid peptides of 40 (Aβ40) and 42 residues (Aβ42) has been considered as one of the hallmarks in the pathology of Alzheimer's disease. In this work, we are able to prepare oligomeric aggregates of Aβ with uniform size and monomorphic structure. Our experimental design is to incubate Aβ peptides in reverse micelles (RMs) so that the peptides could aggregate only through a single nucleation process and the size of the oligomers is confined by the physical dimension of the reverse micelles. The hence obtained Aβ oligomers (AβOs) are 23 nm in diameter and they belong to the category of high molecular-weight (MW) oligomers. The solid-state NMR data revealed that Aβ40Os adopt the structural motif of β-loop-β but the chemical shifts manifested that they may be structurally different from low-MW AβOs and mature fibrils. From the thioflavin-T results, we found that high-MW Aβ42Os can accelerate the fibrillization of Aβ40 monomers. Our protocol allows performing cross-seeding experiments among oligomeric species. By comparing the chemical shifts of Aβ40Os cross seeded by Aβ42Os and those of Aβ40Os prepared in the absence of Aβ42Os, we observed that the chemical states of E11, K16, and E22 were altered, whereas the backbone conformation of the β-sheet region near the C-terminus was structurally invariant. The use of reverse micelles allows hitherto the most detailed characterization of the structural variability of Aβ40Os. Extracellular accumulation of β amyloid peptides of 40 (Aβ40) and 42 residues (Aβ42) has been considered as one of the hallmarks in the pathology of Alzheimer's disease.![]()
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Affiliation(s)
- Han-Wen Chang
- Department of Chemistry, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 10617, Taiwan
| | - Ho-I. Ma
- Department of Chemistry, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 10617, Taiwan
| | - Yi-Shan Wu
- Department of Chemistry, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 10617, Taiwan
| | - Ming-Che Lee
- Department of Chemistry, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 10617, Taiwan
| | - Eric Chung-Yueh Yuan
- Department of Chemistry, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 10617, Taiwan
| | - Shing-Jong Huang
- Instrumentation Center, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 10617, Taiwan
| | - Yu-Sheng Cheng
- Department of Chemistry, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 10617, Taiwan
| | - Meng-Hsin Wu
- Department of Chemistry, National Taiwan Normal University, No. 88, Section 4, Ting-Chow Road, Taipei, 11677, Taiwan
| | - Ling-Hsien Tu
- Department of Chemistry, National Taiwan Normal University, No. 88, Section 4, Ting-Chow Road, Taipei, 11677, Taiwan
| | - Jerry Chun Chung Chan
- Department of Chemistry, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 10617, Taiwan
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14
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Vishvakarma V, Maiti S. Measuring the Size and Spontaneous Fluctuations of Amyloid Aggregates with Fluorescence Correlation Spectroscopy. Methods Mol Biol 2022; 2538:35-54. [PMID: 35951292 DOI: 10.1007/978-1-0716-2529-3_4] [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] [Indexed: 06/15/2023]
Abstract
Bacterial amyloids decorate the cell surface of many bacteria by forming functional amyloid fibers. These amyloids have structural and biochemical similarities with many disease-related amyloids in eukaryotes. Amyloid aggregation starts at the individual monomer level, and the end product is the amyloid fibril. The process of amyloid aggregation involves a continuous increase of the aggregate size, and therefore size is a critical parameter to measure in aggregation experiments. Also, our understanding of the aggregation process, and our ability to design interventions, can benefit from a measurement of the conformational dynamics of proteins undergoing aggregation. Fluorescence correlation spectroscopy (FCS) is perhaps the most sensitive and rapid technique available currently for this purpose. It can measure the average size and the size distribution of molecules and aggregates down to sub-nm length scales and can also measure fast nanosecond time-scale conformational dynamics, all in an equilibrium solution. FCS achieves this by measuring the fluorescence intensity fluctuations of freely diffusing protein molecules in an optically defined microscopic probe volume in a solution. Here, we present a set of instructions for effectively measuring the size and dynamics of amyloid aggregates with FCS.
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Affiliation(s)
- Vicky Vishvakarma
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Sudipta Maiti
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai, India.
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15
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Probing the Influence of Single-Site Mutations in the Central Cross-β Region of Amyloid β (1-40) Peptides. Biomolecules 2021; 11:biom11121848. [PMID: 34944492 PMCID: PMC8699037 DOI: 10.3390/biom11121848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 12/02/2021] [Accepted: 12/07/2021] [Indexed: 11/16/2022] Open
Abstract
Amyloid β (Aβ) is a peptide known to form amyloid fibrils in the brain of patients suffering from Alzheimer’s disease. A complete mechanistic understanding how Aβ peptides form neurotoxic assemblies and how they kill neurons has not yet been achieved. Previous analysis of various Aβ40 mutants could reveal the significant importance of the hydrophobic contact between the residues Phe19 and Leu34 for cell toxicity. For some mutations at Phe19, toxicity was completely abolished. In the current study, we assessed if perturbations introduced by mutations in the direct proximity of the Phe19/Leu34 contact would have similar relevance for the fibrillation kinetics, structure, dynamics and toxicity of the Aβ assemblies. To this end, we rationally modified positions Phe20 or Gly33. A small library of Aβ40 peptides with Phe20 mutated to Lys, Tyr or the non-proteinogenic cyclohexylalanine (Cha) or Gly33 mutated to Ala was synthesized. We used electron microscopy, circular dichroism, X-ray diffraction, solid-state NMR spectroscopy, ThT fluorescence and MTT cell toxicity assays to comprehensively investigate the physicochemical properties of the Aβ fibrils formed by the modified peptides as well as toxicity to a neuronal cell line. Single mutations of either Phe20 or Gly33 led to relatively drastic alterations in the Aβ fibrillation kinetics but left the global, as well as the local structure, of the fibrils largely unchanged. Furthermore, the introduced perturbations caused a severe decrease or loss of cell toxicity compared to wildtype Aβ40. We suggest that perturbations at position Phe20 and Gly33 affect the fibrillation pathway of Aβ40 and, thereby, influence the especially toxic oligomeric species manifesting so that the region around the Phe19/Leu34 hydrophobic contact provides a promising site for the design of small molecules interfering with the Aβ fibrillation pathway.
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16
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Das A, Korn A, Carroll A, Carver JA, Maiti S. Application of the Double-Mutant Cycle Strategy to Protein Aggregation Reveals Transient Interactions in Amyloid-β Oligomers. J Phys Chem B 2021; 125:12426-12435. [PMID: 34748334 DOI: 10.1021/acs.jpcb.1c05829] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Transient oligomeric intermediates in the peptide or protein aggregation pathway are suspected to be the key toxic species in many amyloid diseases, but deciphering their molecular nature has remained a challenge. Here we show that the strategy of "double-mutant cycles", used effectively in probing protein-folding intermediates, can reveal transient interactions during protein aggregation. It does so by comparing the changes in thermodynamic parameters between the wild type, and single and double mutants. We demonstrate the strategy by probing the possible transient salt bridge partner of lysine 28 (K28) in the oligomeric states of amyloid β-40 (Aβ40), the putative toxic species in Alzheimer's disease. In mature fibrils, the binding partner is aspartate 23. This interaction differentiates Aβ40 from the more toxic Aβ42, where K28's binding partner is the C-terminal carboxylate. We selectively acetylated K28 and amidated the C-terminus of Aβ40, creating four distinct variants. Spectroscopic measurements of the kinetics and thermodynamics of aggregation show that K28 and the C-terminus interact transiently in the early phases of the Aβ40 aggregation pathway. Hydrogen-deuterium exchange mass spectrometry (using a simple analysis method that we introduce here that takes into account the isotopic mass distribution) supports this interpretation. It is also supported by cellular toxicity measurements, suggesting possible similarities in the mechanisms of toxicity of Aβ40 oligomers (which are more toxic than Aβ40 fibrils) and Aβ42. Our results show that double-mutant cycles can be a powerful tool for probing transient interactions during protein aggregation.
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Affiliation(s)
- Anirban Das
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Alexander Korn
- Institute for Medical Physics and Biophysics, Leipzig University, Härtelstr. 16-18, D-04107 Leipzig, Germany
| | - Adam Carroll
- Research School of Chemistry, The Australian National University, Acton, Australian Capital Territory 2601, Australia
| | - John A Carver
- Research School of Chemistry, The Australian National University, Acton, Australian Capital Territory 2601, Australia
| | - Sudipta Maiti
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
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17
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Li Y, Tang H, Zhu H, Kakinen A, Wang D, Andrikopoulos N, Sun Y, Nandakumar A, Kwak E, Davis TP, Leong DT, Ding F, Ke PC. Ultrasmall Molybdenum Disulfide Quantum Dots Cage Alzheimer's Amyloid Beta to Restore Membrane Fluidity. ACS APPLIED MATERIALS & INTERFACES 2021; 13:29936-29948. [PMID: 34143617 PMCID: PMC8251662 DOI: 10.1021/acsami.1c06478] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Alzheimer's disease (AD) is a major cause of dementia characterized by the overexpression of transmembrane amyloid precursor protein and its neurotoxic byproduct amyloid beta (Aβ). A small peptide of considerable hydrophobicity, Aβ is aggregation prone catalyzed by the presence of cell membranes, among other environmental factors. Accordingly, current AD mitigation strategies often aim at breaking down the Aβ-membrane communication, yet no data is available concerning the cohesive interplay of the three key entities of the cell membrane, Aβ, and its inhibitor. Using a lipophilic Laurdan dye and confocal fluorescence microscopy, we observed cell membrane perturbation and actin reorganization induced by Aβ oligomers but not by Aβ monomers or amyloid fibrils. We further revealed recovery of membrane fluidity by ultrasmall MoS2 quantum dots, also shown in this study as a potent inhibitor of Aβ amyloid aggregation. Using discrete molecular dynamics simulations, we uncovered the binding of MoS2 and Aβ monomers as mediated by hydrophilic interactions between the quantum dots and the peptide N-terminus. In contrast, Aβ oligomers and fibrils were surface-coated by the ultrasmall quantum dots in distinct testudo-like, reverse protein-corona formations to prevent their further association with the cell membrane and adverse effects downstream. This study offers a crucial new insight and a viable strategy for regulating the amyloid aggregation and membrane-axis of AD pathology with multifunctional nanomedicine.
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Affiliation(s)
- Yuhuan Li
- Liver Cancer Institute, Zhongshan Hospital, Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Fudan University, Shanghai, 200032, China
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Huayuan Tang
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, United States
| | - Houjuan Zhu
- National University of Singapore, Department of Chemical and Biomolecular Engineering, 4 Engineering Drive 4, Singapore 117585, Singapore
| | - Aleksandr Kakinen
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane Qld 4072, Australia
| | - Di Wang
- School of Life Sciences, Jilin University, Changchun 130012, China
| | - Nicholas Andrikopoulos
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Yunxiang Sun
- School of Physical Science and Technology, Ningbo University, Ningbo 315211, China
| | - Aparna Nandakumar
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Eunbi Kwak
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Thomas P. Davis
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane Qld 4072, Australia
| | - David Tai Leong
- National University of Singapore, Department of Chemical and Biomolecular Engineering, 4 Engineering Drive 4, Singapore 117585, Singapore
| | - Feng Ding
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, United States
| | - Pu Chun Ke
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane Qld 4072, Australia
- The GBA National Institute for Nanotechnology Innovation, 136 Kaiyuan Avenue, Guangzhou, 510700, China
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18
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Fu Z, Van Nostrand WE, Smith SO. Anti-Parallel β-Hairpin Structure in Soluble Aβ Oligomers of Aβ40-Dutch and Aβ40-Iowa. Int J Mol Sci 2021; 22:ijms22031225. [PMID: 33513738 PMCID: PMC7865275 DOI: 10.3390/ijms22031225] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/20/2021] [Accepted: 01/24/2021] [Indexed: 11/16/2022] Open
Abstract
The amyloid-β (Aβ) peptides are associated with two prominent diseases in the brain, Alzheimer’s disease (AD) and cerebral amyloid angiopathy (CAA). Aβ42 is the dominant component of cored parenchymal plaques associated with AD, while Aβ40 is the predominant component of vascular amyloid associated with CAA. There are familial CAA mutations at positions Glu22 and Asp23 that lead to aggressive Aβ aggregation, drive vascular amyloid deposition and result in degradation of vascular membranes. In this study, we compared the transition of the monomeric Aβ40-WT peptide into soluble oligomers and fibrils with the corresponding transitions of the Aβ40-Dutch (E22Q), Aβ40-Iowa (D23N) and Aβ40-Dutch, Iowa (E22Q, D23N) mutants. FTIR measurements show that in a fashion similar to Aβ40-WT, the familial CAA mutants form transient intermediates with anti-parallel β-structure. This structure appears before the formation of cross-β-sheet fibrils as determined by thioflavin T fluorescence and circular dichroism spectroscopy and occurs when AFM images reveal the presence of soluble oligomers and protofibrils. Although the anti-parallel β-hairpin is a common intermediate on the pathway to Aβ fibrils for the four peptides studied, the rate of conversion to cross-β-sheet fibril structure differs for each.
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Affiliation(s)
- Ziao Fu
- Center for Structural Biology, Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, USA;
| | - William E. Van Nostrand
- George and Anne Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI 02881, USA;
- Department of Biomedical and Pharmaceutical Sciences, University of Rhode Island, Kingston, RI 02881, USA
| | - Steven O. Smith
- Center for Structural Biology, Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, USA;
- Correspondence: ; Tel.: +1-631-632-1210
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19
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Scheidt HA, Das A, Korn A, Krueger M, Maiti S, Huster D. Structural characteristics of oligomers formed by pyroglutamate-modified amyloid β peptides studied by solid-state NMR. Phys Chem Chem Phys 2020; 22:16887-16895. [PMID: 32666970 DOI: 10.1039/d0cp02307h] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Neuronal plaques of amyloid β (Aβ) peptides of varying length carrying different posttranslational modifications represent a molecular hallmark of Alzheimer's disease. It is believed that transient oligomeric Aβ assemblies associating in early fibrillation events represent particularly cytotoxic peptide aggregates. Also, N-terminally truncated (in position 3 or 11) and pyroglutamate modified peptides exhibited an increased toxicity compared to the wildtype. In the current study, the molecular structure of oligomeric species of pGlu3-Aβ(3-40) and pGlu11-Aβ(11-40) was investigated using solid-state NMR spectroscopy. On the secondary structure level, for both modified peptides a large similarity between oligomers and mature fibrils of the modified peptides was found mainly based on 13C NMR chemical shift data. Some smaller structural differences were detected in the vicinity of the respective modification site. Also, the crucial early folding molecular contact between residues Phe19 and Leu34 could be observed for the oligomers of both modified peptide species. Therefore, it has to be concluded that the major secondary structure elements of Aβ are already present in oligomers of pGlu3-Aβ(3-40) and pGlu11-Aβ(11-40). These posttranslationally modified peptides arrange in a similar fashion as observed for wild type Aβ(1-40).
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Affiliation(s)
- Holger A Scheidt
- Institute for Medical Physics and Biophysics, Leipzig University Härtelstr. 16-18, D-04107 Leipzig, Germany.
| | - Anirban Das
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005, India
| | - Alexander Korn
- Institute for Medical Physics and Biophysics, Leipzig University Härtelstr. 16-18, D-04107 Leipzig, Germany.
| | - Martin Krueger
- Institute of Anatomy, Leipzig University, Liebigstraße 13, 04103 Leipzig, Germany
| | - Sudipta Maiti
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005, India
| | - Daniel Huster
- Institute for Medical Physics and Biophysics, Leipzig University Härtelstr. 16-18, D-04107 Leipzig, Germany. and Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005, India
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20
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Mora AK, Murudkar S, Shivran N, Mula S, Chattopadhyay S, Nath S. Monitoring the formation of insulin oligomers using a NIR emitting glucose-conjugated BODIPY dye. Int J Biol Macromol 2020; 166:1121-1130. [PMID: 33159943 DOI: 10.1016/j.ijbiomac.2020.10.267] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 09/17/2020] [Accepted: 10/31/2020] [Indexed: 10/23/2022]
Abstract
Protein oligomers, which are formed due to the aggregation of protein molecules under physiological stress, are neurotoxic and responsible for several neurological diseases. Early detection of protein oligomers is essential for the timely intervention in the associated diseases. Although several probes have been developed for the detection of insoluble matured protein fibrils, fluorescent probes with emission in the near infrared (NIR) region for probing protein oligomers are very rare. In the present study we have designed and synthesized a glucose-conjugated BODIPY dye with emission in the NIR spectral range. Our detailed studies show that the new probe is not only capable of detecting matured fibrils but can also probe the formation of oligomers from the native protein. The new probe shows a large increase in its emission intensity upon association with oligomers and matured fibrils. Hence, the present probe has a great potential for the in vivo imaging of protein oligomers and matured fibrils. Detailed spectroscopic properties of the new probes in molecular solvents have been performed to understand its oligomers- and fibril- sensing mechanism.
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Affiliation(s)
- Aruna K Mora
- Radiation & Photochemistry Division, Bhabha Atomic Research Centre, Mumbai 400085, India
| | - Sushant Murudkar
- Radiation & Photochemistry Division, Bhabha Atomic Research Centre, Mumbai 400085, India
| | - Neelam Shivran
- Bio-Organic Division, Bhabha Atomic Research Centre, Mumbai 400085, India
| | - Soumyaditya Mula
- Bio-Organic Division, Bhabha Atomic Research Centre, Mumbai 400085, India; Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India
| | | | - Sukhendu Nath
- Radiation & Photochemistry Division, Bhabha Atomic Research Centre, Mumbai 400085, India; Homi Bhabha National Institute, Anushaktinagar, Mumbai 400094, India.
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21
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Das A, Gupta A, Hong Y, Carver JA, Maiti S. A Spectroscopic Marker for Structural Transitions Associated with Amyloid-β Aggregation. Biochemistry 2020; 59:1813-1822. [PMID: 32329604 DOI: 10.1021/acs.biochem.0c00113] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
An amyloid aggregate evolves through a series of intermediates that have different secondary structures and intra- and intermolecular contacts. The structural parameters of these intermediates are important determinants of their toxicity. For example, the early oligomeric species of the amyloid-β (Aβ) peptide have been implicated as the most cytotoxic species in Alzheimer's disease but are difficult to identify because of their dynamic and transitory nature. Conventional aggregation monitors such as the fluorescent dye thioflavin T report on only the overall transition of the soluble species to the final amyloid fibrillar aggregated state. Here, we show that the fluorescent dye bis(triphenylphosphonium) tetraphenylethene (TPE-TPP) identifies at least three distinct aggregation intermediates of Aβ. Some atomic-level features of these intermediates are known from solid state nuclear magnetic resonance spectroscopy. Hence, the TPE-TPP fluorescence data may be interpreted in terms of these Aβ structural transitions. Steady state fluorescence and lifetime characteristics of TPE-TPP distinguish between the small oligomeric species (emission wavelength maximum, λmax = 465 nm; average fluorescence lifetime, τFl measured at 420 nm = 3.58 ± 0.04 ns), the intermediate species (λmax = 452 nm; τFl = 3.00 ± 0.03 ns), and the fibrils (λmax = 406 nm; τFl = 5.19 ± 0.08 ns). Thus, TPE-TPP provides a ready diagnostic for differentiating between the various, including the toxic, Aβ aggregates and potentially can be utilized to screen for amyloid aggregation inhibitors.
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Affiliation(s)
- Anirban Das
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Ankur Gupta
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Yuning Hong
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, VIC 3086, Australia
| | - John A Carver
- Research School of Chemistry, The Australian National University, Acton, ACT 2601, Australia
| | - Sudipta Maiti
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
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22
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Sahoo BR, Cox SJ, Ramamoorthy A. High-resolution probing of early events in amyloid-β aggregation related to Alzheimer's disease. Chem Commun (Camb) 2020; 56:4627-4639. [PMID: 32300761 PMCID: PMC7254607 DOI: 10.1039/d0cc01551b] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
In Alzheimer's disease (AD), soluble oligomers of amyloid-β (Aβ) are emerging as a crucial entity in driving disease progression as compared to insoluble amyloid deposits. The lacuna in establishing the structure to function relationship for Aβ oligomers prevents the development of an effective treatment for AD. While the transient and heterogeneous properties of Aβ oligomers impose many challenges for structural investigation, an effective use of a combination of NMR techniques has successfully identified and characterized them at atomic-resolution. Here, we review the successful utilization of solution and solid-state NMR techniques to probe the aggregation and structures of small and large oligomers of Aβ. Biophysical studies utilizing the commonly used solution and 19F based NMR experiments to identify the formation of small size early intermediates and to obtain their structures, and dock-lock mechanism of fiber growth at atomic-resolution are discussed. In addition, the use of proton-detected magic angle spinning (MAS) solid-state NMR experiments to obtain high-resolution insights into the aggregation pathways and structures of large oligomers and other aggregates is also presented. We expect these NMR based studies to be valuable for real-time monitoring of the depletion of monomers and the formation of toxic oligomers and high-order aggregates under a variety of conditions, and to solve the high-resolution structures of small and large size oligomers for most amyloid proteins, and therefore to develop inhibitors and drugs.
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Affiliation(s)
- Bikash R Sahoo
- Biophysics Program, Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA.
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23
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Griner SL, Seidler P, Bowler J, Murray KA, Yang TP, Sahay S, Sawaya MR, Cascio D, Rodriguez JA, Philipp S, Sosna J, Glabe CG, Gonen T, Eisenberg DS. Structure-based inhibitors of amyloid beta core suggest a common interface with tau. eLife 2019; 8:46924. [PMID: 31612856 PMCID: PMC6850776 DOI: 10.7554/elife.46924] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Accepted: 10/04/2019] [Indexed: 01/04/2023] Open
Abstract
Alzheimer’s disease (AD) pathology is characterized by plaques of amyloid beta (Aβ) and neurofibrillary tangles of tau. Aβ aggregation is thought to occur at early stages of the disease, and ultimately gives way to the formation of tau tangles which track with cognitive decline in humans. Here, we report the crystal structure of an Aβ core segment determined by MicroED and in it, note characteristics of both fibrillar and oligomeric structure. Using this structure, we designed peptide-based inhibitors that reduce Aβ aggregation and toxicity of already-aggregated species. Unexpectedly, we also found that these inhibitors reduce the efficiency of Aβ-mediated tau aggregation, and moreover reduce aggregation and self-seeding of tau fibrils. The ability of these inhibitors to interfere with both Aβ and tau seeds suggests these fibrils share a common epitope, and supports the hypothesis that cross-seeding is one mechanism by which amyloid is linked to tau aggregation and could promote cognitive decline.
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Affiliation(s)
- Sarah L Griner
- UCLA-DOE Institute, Department of Biological Chemistry, Molecular Biology Institute, Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, United States
| | - Paul Seidler
- UCLA-DOE Institute, Department of Biological Chemistry, Molecular Biology Institute, Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, United States
| | - Jeannette Bowler
- UCLA-DOE Institute, Department of Biological Chemistry, Molecular Biology Institute, Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, United States
| | - Kevin A Murray
- UCLA-DOE Institute, Department of Biological Chemistry, Molecular Biology Institute, Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, United States
| | - Tianxiao Peter Yang
- UCLA-DOE Institute, Department of Biological Chemistry, Molecular Biology Institute, Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, United States
| | - Shruti Sahay
- UCLA-DOE Institute, Department of Biological Chemistry, Molecular Biology Institute, Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, United States
| | - Michael R Sawaya
- UCLA-DOE Institute, Department of Biological Chemistry, Molecular Biology Institute, Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, United States
| | - Duilio Cascio
- UCLA-DOE Institute, Department of Biological Chemistry, Molecular Biology Institute, Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, United States
| | - Jose A Rodriguez
- UCLA-DOE Institute, Department of Biological Chemistry, Molecular Biology Institute, Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, United States
| | - Stephan Philipp
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, United States
| | - Justyna Sosna
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, United States
| | - Charles G Glabe
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, United States.,Biochemistry Department, Faculty of Science and Experimental Biochemistry Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Tamir Gonen
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, United States
| | - David S Eisenberg
- UCLA-DOE Institute, Department of Biological Chemistry, Molecular Biology Institute, Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, United States
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24
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Hashemi M, Zhang Y, Lv Z, Lyubchenko YL. Spontaneous self-assembly of amyloid β (1-40) into dimers. NANOSCALE ADVANCES 2019; 1:3892-3899. [PMID: 36132110 PMCID: PMC9417245 DOI: 10.1039/c9na00380k] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 09/16/2019] [Indexed: 05/17/2023]
Abstract
The self-assembly and fibrillation of amyloid β (Aβ) proteins is the neuropathological hallmark of Alzheimer's disease. However, the molecular mechanism of how disordered monomers assemble into aggregates remains largely unknown. In this work, we characterize the assembly of Aβ (1-40) monomers into dimers using long-time molecular dynamics simulations. Upon interaction, the monomers undergo conformational transitions, accompanied by change of the structure, leading to the formation of a stable dimer. The dimers are stabilized by interactions in the N-terminal region (residues 5-12), in the central hydrophobic region (residues 16-23), and in the C-terminal region (residues 30-40); with inter-peptide interactions focused around the N- and C-termini. The dimers do not contain long β-strands that are usually found in fibrils.
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Affiliation(s)
- Mohtadin Hashemi
- Department of Pharmaceutical Sciences, 986025 Nebraska Medical Center, University of Nebraska Medical Center Omaha NE 68198 USA
| | - Yuliang Zhang
- Department of Pharmaceutical Sciences, 986025 Nebraska Medical Center, University of Nebraska Medical Center Omaha NE 68198 USA
- Biology and Biotechnology Division, Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory Livermore CA 94550 USA
| | - Zhengjian Lv
- Department of Pharmaceutical Sciences, 986025 Nebraska Medical Center, University of Nebraska Medical Center Omaha NE 68198 USA
- Bruker Nano Surfaces Division 112 Robin Hill Road Goleta, Santa Barbara CA 93117 USA
| | - Yuri L Lyubchenko
- Department of Pharmaceutical Sciences, 986025 Nebraska Medical Center, University of Nebraska Medical Center Omaha NE 68198 USA
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25
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His6, His13, and His14 residues in Aβ 1-40 peptide significantly and specifically affect oligomeric equilibria. Sci Rep 2019; 9:9449. [PMID: 31263161 PMCID: PMC6602940 DOI: 10.1038/s41598-019-45988-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 06/20/2019] [Indexed: 11/12/2022] Open
Abstract
Oligomers of Aβ peptide are implicated as the most probable causative agent in Alzheimer’s disease. However, their structural properties remain elusive due to the dynamic and heterogeneous character of oligomeric species coexisting in solution. Nevertheless, new approaches, mainly based on mass spectrometry, provide unique access to these different structural forms. Using these methods, we previously showed that the N-terminal, non-amyloidogenic region of Aβ is involved in the network of interactions specifically stabilizing oligomers. In the present study, we identified three histidine residues as active participants in this network. Detailed knowledge of the structural features that are potentially important for oligomer-mediated neurotoxicity is a prerequisite for the rational design of oligomerization modifiers.
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26
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Maity BK, Das AK, Dey S, Moorthi UK, Kaur A, Dey A, Surendran D, Pandit R, Kallianpur M, Chandra B, Chandrakesan M, Arumugam S, Maiti S. Ordered and Disordered Segments of Amyloid-β Drive Sequential Steps of the Toxic Pathway. ACS Chem Neurosci 2019; 10:2498-2509. [PMID: 30763064 DOI: 10.1021/acschemneuro.9b00015] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
While the roles of intrinsically disordered protein domains in driving interprotein interactions are increasingly well-appreciated, the mechanism of toxicity of disease-causing disordered proteins remains poorly understood. A prime example is Alzheimer's disease (AD) associated amyloid beta (Aβ). Aβ oligomers are highly toxic partially structured peptide assemblies with a distinct ordered region (residues ∼10-40) and a shorter disordered region (residues ∼1-9). Here, we investigate the role of this disordered domain and its relation to the ordered domain in the manifestation of toxicity through a set of Aβ fragments and stereoisomers designed for this purpose. We measure their effects on lipid membranes and cultured neurons, probing their toxicity, intracellular distributions, and specific molecular interactions using the techniques of confocal imaging, lattice light sheet imaging, fluorescence lifetime imaging, and fluorescence correlation spectroscopy. Remarkably, we find that neither part-Aβ10-40 or Aβ1-9, is toxic by itself. The ordered part (Aβ10-40) is the major determinant of how Aβ attaches to lipid bilayers, enters neuronal cells, and localizes primarily in the late endosomal compartments. However, once Aβ enters the cell, it is the disordered part (only when it is connected to the rest of the peptide) that has a strong and stereospecific interaction with an unknown cellular component, as demonstrated by distinct changes in the fluorescence lifetime of a fluorophore attached to the N-terminal. This interaction appears to commit Aβ to the toxic pathway. Our findings correlate well with Aβ sites of familial AD mutations, a significant fraction of which cluster in the disordered region. We conclude that, while the ordered region dictates attachment and cellular entry, the key to toxicity lies in the ordered part presenting the disordered part for a specific cellular interaction.
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Affiliation(s)
- Barun Kumar Maity
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Anand Kant Das
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Simli Dey
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | | | | | - Arpan Dey
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Dayana Surendran
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Rucha Pandit
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Mamata Kallianpur
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Bappaditya Chandra
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Muralidharan Chandrakesan
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | | | - Sudipta Maiti
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
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27
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Martinez Hernandez A, Urbanke H, Gillman AL, Lee J, Ryazanov S, Agbemenyah HY, Benito E, Jain G, Kaurani L, Grigorian G, Leonov A, Rezaei-Ghaleh N, Wilken P, Arce FT, Wagner J, Fuhrmann M, Caruana M, Camilleri A, Vassallo N, Zweckstetter M, Benz R, Giese A, Schneider A, Korte M, Lal R, Griesinger C, Eichele G, Fischer A. The diphenylpyrazole compound anle138b blocks Aβ channels and rescues disease phenotypes in a mouse model for amyloid pathology. EMBO Mol Med 2019; 10:32-47. [PMID: 29208638 PMCID: PMC5760857 DOI: 10.15252/emmm.201707825] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Alzheimer's disease is a devastating neurodegenerative disease eventually leading to dementia. An effective treatment does not yet exist. Here we show that oral application of the compound anle138b restores hippocampal synaptic and transcriptional plasticity as well as spatial memory in a mouse model for Alzheimer's disease, when given orally before or after the onset of pathology. At the mechanistic level, we provide evidence that anle138b blocks the activity of conducting Aβ pores without changing the membrane embedded Aβ-oligomer structure. In conclusion, our data suggest that anle138b is a novel and promising compound to treat AD-related pathology that should be investigated further.
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Affiliation(s)
- Ana Martinez Hernandez
- Department for Epigenetics and Systems Medicine in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany.,Department for Genes and Behavior, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Hendrik Urbanke
- Department for Epigenetics and Systems Medicine in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany
| | - Alan L Gillman
- Department of Bioengineering, Materials Science and Engineering, Department of Mechanical and Aerospace Engineering and Institute of Engineering in Medicine, University of California San Diego, La Jolla, CA, USA
| | - Joon Lee
- Department of Bioengineering, Materials Science and Engineering, Department of Mechanical and Aerospace Engineering and Institute of Engineering in Medicine, University of California San Diego, La Jolla, CA, USA
| | - Sergey Ryazanov
- Department of NMR Based Structural Biology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.,DFG Research Center Nanoscale Microscopy and Molecular Physiology of the Brain, Göttingen, Germany
| | - Hope Y Agbemenyah
- Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Göttingen, Germany
| | - Eva Benito
- Department for Epigenetics and Systems Medicine in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany
| | - Gaurav Jain
- Department for Epigenetics and Systems Medicine in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany
| | - Lalit Kaurani
- DFG Research Center Nanoscale Microscopy and Molecular Physiology of the Brain, Göttingen, Germany
| | - Gayane Grigorian
- Department of Cellular Neurobiology, Technical University Braunschweig, Braunschweig, Germany
| | - Andrei Leonov
- Department of NMR Based Structural Biology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.,DFG Research Center Nanoscale Microscopy and Molecular Physiology of the Brain, Göttingen, Germany
| | - Nasrollah Rezaei-Ghaleh
- Department of NMR Based Structural Biology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.,Department of Translational Structural Biology of Dementia, German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany
| | - Petra Wilken
- DFG Research Center Nanoscale Microscopy and Molecular Physiology of the Brain, Göttingen, Germany.,Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Göttingen, Germany.,Group for Translational Research in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE) Göttingen, Göttingen, Germany
| | - Fernando Teran Arce
- Department of Bioengineering, Materials Science and Engineering, Department of Mechanical and Aerospace Engineering and Institute of Engineering in Medicine, University of California San Diego, La Jolla, CA, USA
| | - Jens Wagner
- Group for Neuroimmunology and Imaging, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Martin Fuhrmann
- Group for Neuroimmunology and Imaging, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Mario Caruana
- Department of Physiology and Biochemistry, Centre for Molecular Medicine and Biobanking, University of Malta, Msida, Malta
| | - Angelique Camilleri
- Department of Physiology and Biochemistry, Centre for Molecular Medicine and Biobanking, University of Malta, Msida, Malta
| | - Neville Vassallo
- Department of Physiology and Biochemistry, Centre for Molecular Medicine and Biobanking, University of Malta, Msida, Malta
| | - Markus Zweckstetter
- Department of NMR Based Structural Biology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.,DFG Research Center Nanoscale Microscopy and Molecular Physiology of the Brain, Göttingen, Germany.,Department of Translational Structural Biology of Dementia, German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany.,Department of Neurology, University Medical Center Göttingen, University of Göttingen, Göttingen, Germany
| | - Roland Benz
- Life Sciences and Chemistry, Jacobs University of Bremen, Bremen, Germany
| | - Armin Giese
- Center for Neuropathology and Prion Research, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Anja Schneider
- DFG Research Center Nanoscale Microscopy and Molecular Physiology of the Brain, Göttingen, Germany.,Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Göttingen, Germany.,Group for Translational Research in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE) Göttingen, Göttingen, Germany
| | - Martin Korte
- Department of Cellular Neurobiology, Technical University Braunschweig, Braunschweig, Germany .,Helmholtz Center for Infections Research, Braunschweig, Germany
| | - Ratnesh Lal
- Department of Bioengineering, Materials Science and Engineering, Department of Mechanical and Aerospace Engineering and Institute of Engineering in Medicine, University of California San Diego, La Jolla, CA, USA
| | - Christian Griesinger
- Department of NMR Based Structural Biology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany .,DFG Research Center Nanoscale Microscopy and Molecular Physiology of the Brain, Göttingen, Germany
| | - Gregor Eichele
- Department for Genes and Behavior, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Andre Fischer
- Department for Epigenetics and Systems Medicine in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany .,Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Göttingen, Germany
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28
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Itoh SG, Yagi-Utsumi M, Kato K, Okumura H. Effects of a Hydrophilic/Hydrophobic Interface on Amyloid-β Peptides Studied by Molecular Dynamics Simulations and NMR Experiments. J Phys Chem B 2019; 123:160-169. [PMID: 30543290 DOI: 10.1021/acs.jpcb.8b11609] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Oligomer formation of amyloid-β peptides (Aβ) is accelerated at a hydrophilic/hydrophobic interface. However, details of the acceleration mechanism have not been elucidated. To understand the effects of the interface on oligomerization at the atomic level, we performed molecular dynamics simulations for an Aβ40 monomer in the presence and absence of the hydrophilic/hydrophobic interface. Nuclear magnetic resonance experiments of Aβ40 peptides with gangliosidic micelles were also carried out. In the simulations and experiments, the hydrophobic residues of Aβ40 bound to the interface stably. Moreover, we found that Aβ40 formed a hairpin structure at the interface more readily than in bulk water. From these results, we discussed the acceleration mechanism of the oligomer formation at the interface.
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Affiliation(s)
- Satoru G Itoh
- Institute for Molecular Science (IMS) , National Institutes of Natural Sciences , Okazaki , Aichi 444-8585 , Japan.,Exploratory Research Center on Life and Living Systems (ExCELLS) , National Institutes of Natural Sciences , Okazaki , Aichi 444-8787 , Japan.,Department of Structural Molecular Science , SOKENDAI (The Graduate University for Advanced Studies) , Okazaki , Aichi 444-8585 , Japan
| | - Maho Yagi-Utsumi
- Institute for Molecular Science (IMS) , National Institutes of Natural Sciences , Okazaki , Aichi 444-8585 , Japan.,Exploratory Research Center on Life and Living Systems (ExCELLS) , National Institutes of Natural Sciences , Okazaki , Aichi 444-8787 , Japan.,Department of Functional Molecular Science , SOKENDAI (The Graduate University for Advanced Studies) , Okazaki , Aichi 444-8787 , Japan.,Graduate School of Pharmaceutical Sciences , Nagoya City University , Nagoya , Aichi 465-8603 , Japan
| | - Koichi Kato
- Institute for Molecular Science (IMS) , National Institutes of Natural Sciences , Okazaki , Aichi 444-8585 , Japan.,Exploratory Research Center on Life and Living Systems (ExCELLS) , National Institutes of Natural Sciences , Okazaki , Aichi 444-8787 , Japan.,Department of Functional Molecular Science , SOKENDAI (The Graduate University for Advanced Studies) , Okazaki , Aichi 444-8787 , Japan.,Graduate School of Pharmaceutical Sciences , Nagoya City University , Nagoya , Aichi 465-8603 , Japan
| | - Hisashi Okumura
- Institute for Molecular Science (IMS) , National Institutes of Natural Sciences , Okazaki , Aichi 444-8585 , Japan.,Exploratory Research Center on Life and Living Systems (ExCELLS) , National Institutes of Natural Sciences , Okazaki , Aichi 444-8787 , Japan.,Department of Structural Molecular Science , SOKENDAI (The Graduate University for Advanced Studies) , Okazaki , Aichi 444-8585 , Japan
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29
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Zhan Q, Shi X, Wang T, Hu J, Zhou J, Zhou L, Wei S. Design and synthesis of thymine modified phthalocyanine for Aβ protofibrils photodegradation and Aβ peptide aggregation inhibition. Talanta 2019; 191:27-38. [DOI: 10.1016/j.talanta.2018.08.037] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 08/06/2018] [Accepted: 08/12/2018] [Indexed: 10/28/2022]
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30
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Zhang X, Huai Y, Cai J, Song C, Zhang Y. Novel antibody against oligomeric amyloid-β: Insight into factors for effectively reducing the aggregation and cytotoxicity of amyloid-β aggregates. Int Immunopharmacol 2018; 67:176-185. [PMID: 30553911 DOI: 10.1016/j.intimp.2018.12.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 11/06/2018] [Accepted: 12/05/2018] [Indexed: 12/27/2022]
Abstract
Amyloid-beta 42 (Aβ42) aggregates represent a prominent histopathological feature in Alzheimer's disease (AD); thus, immunotherapy against oligomeric Aβ42 aggregates is considered to be a potentially safe and specific therapeutic strategy. In this study, we identified an anti-oligomeric Aβ42 aggregate single-chain variable fragment (scFv) antibody, HT6, that is capable of efficiently binding to medium-sized Aβ42 aggregates (mainly 18-45 kDa) in vitro with an equilibrium dissociation constant (KD) of 3.0 × 10-6 M, whether they were derived from Aβ42 monomer, larger Aβ42 oligomers, or even fibrils. This ability allowed scFv HT6 to induce the gradual disassembly of large Aβ42 aggregates into small Aβ42 oligomers while simultaneously effectively inhibiting the further development of Aβ42 aggregates. Moreover, the scFv HT6-targeted conformational region on Aβ42 aggregates was found to be more local and relatively close to the N-terminus of Aβ42; thus, scFv HT6 significantly delayed or even prevented the aggregation of Aβ42 protofibrils, while significantly reducing the cytotoxicity of Aβ42 oligomers. Overall, this study demonstrate that even though the decrease in the cytotoxicity of Aβ42 aggregates might be closely related to the reduction in Aβ42 aggregates and vice versa, the reduction in Aβ42 aggregates might not necessarily be accompanied by or followed by the reduction or even elimination of the cytotoxicity of Aβ42 aggregates. This insight enriches the diversity of anti-oligomeric Aβ42 antibodies, further providing a new understanding into the relationship between their binding pattern to Aβ42 aggregates and the efficacy against their formation, offering a therapeutic strategy to delay the progression of AD.
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Affiliation(s)
- Xiaoning Zhang
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, Jilin University, Changchun, China
| | - Yangyang Huai
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, Jilin University, Changchun, China
| | - Jing Cai
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, Jilin University, Changchun, China; China-Japan Union Hospital of Jilin University, Changchun, China
| | - Chuli Song
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, Jilin University, Changchun, China
| | - Yingjiu Zhang
- Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, Jilin University, Changchun, China; School of Life Science, Jilin University, Changchun, China.
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31
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Przygońska K, Poznański J, Mistarz UH, Rand KD, Dadlez M. Side-chain moieties from the N-terminal region of Aβ are Involved in an oligomer-stabilizing network of interactions. PLoS One 2018; 13:e0201761. [PMID: 30080867 PMCID: PMC6078298 DOI: 10.1371/journal.pone.0201761] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 07/20/2018] [Indexed: 12/31/2022] Open
Abstract
Oligomeric forms of the Aβ peptide represent the most probable neurotoxic agent in Alzheimer’s disease. The dynamic and heterogeneous character of these oligomers makes their structural characterization by classic methods difficult. Native mass spectrometry, when supported by additional gas phase techniques, like ion mobility separation and hydrogen-deuterium exchange (IM-HDX-MS), enable analysis of different oligomers coexisting in the sample and may provide species-specific structural information for each oligomeric form populated in the gas phase. Here, we have combined these three techniques to obtain insight into the structural properties of oligomers of Aβ1–40 and two variants with scrambled sequences. Gas-phase HDX-MS revealed a sequence-specific engagement of the side-chains of residues located at the N-terminal part of the peptide in a network of oligomer-stabilizing interactions. Oligomer-specific interactions were no longer observed in the case of the fully scrambled sequence. Also, the ability to form alternative structures, observed for WT Aβ peptide, was lost upon scrambling. Our data underscore a role for the N-terminal residues in shaping the equilibria of oligomeric forms. Although the peptide lacking the N-terminal 1–16 residues (p3 peptide) is thought to be benign, the role of the N-terminus has not been sufficiently characterized yet. We speculate that the interaction networks revealed here may be crucial for enabling structural transitions necessary to obtain mature parallel cross-β structures from smaller antiparallel oligomers. We provide a hypothetical molecular model of the trajectory that allows a gradual conversion from antiparallel to parallel oligomers without decomposition of oligomers. Oligomer-defining interactions involving the Aβ peptide N-terminus may be important in production of the neurotoxic forms and thus should not be neglected.
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Affiliation(s)
- Kaja Przygońska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Jarosław Poznański
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Ulrik H. Mistarz
- Department of Pharmacy, University of Copenhagen, Copenhagen, Denmark
| | - Kasper D. Rand
- Department of Pharmacy, University of Copenhagen, Copenhagen, Denmark
| | - Michał Dadlez
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
- Institute of Genetics and Biotechnology, Department of Biology, University of Warsaw, Warsaw, Poland
- * E-mail:
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32
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Korn A, McLennan S, Adler J, Krueger M, Surendran D, Maiti S, Huster D. Amyloid β (1-40) Toxicity Depends on the Molecular Contact between Phenylalanine 19 and Leucine 34. ACS Chem Neurosci 2018; 9:790-799. [PMID: 29232098 DOI: 10.1021/acschemneuro.7b00360] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The formation of the hydrophobic contact between phenylalanine 19 (F19) and leucine 34 (L34) of amyloid β (1-40) (Aβ(1-40)) is known to be an important step in the fibrillation of Aβ(1-40) peptides. Mutations of this putatively early molecular contact were shown to strongly influence the toxicity of Aβ(1-40) ( Das et al. ( 2015 ) ACS Chem. Neurosci. 6 , 1290 - 1295 ). Any mutation of residue F19 completely abolished the toxicity of Aβ(1-40), suggesting that a proper F19-L34 contact is crucial also for the formation of transient oligomers. In this work, we investigate a series of isomeric substitutions of L34, namely, d-leucine, isoleucine, and valine, to study further details of this molecular contact. These replacements represent very minor alterations in the Aβ(1-40) structure posing the question how these alterations challenge the fibrillation kinetics, structure, dynamics, and toxicity of the Aβ(1-40) aggregates. Our work involves kinetic studies using thioflavin T, transmission electron microscopy, X-ray diffraction for the analysis of the fibril morphology, and nuclear magnetic resonance experiments for local structure and molecular dynamics investigations. Combined with cell toxicity assays of the mutated Aβ(1-40) peptides, the physicochemical and biological importance of the early folding contact between F19 and L34 in Aβ(1-40) is underlined. This implies that the F19-L34 contact influences a broad range of different processes including the initiation of fibrillation, oligomer stability, fibril elongation, local fibril structure, and dynamics and cellular toxicity. These processes do not only cover a broad range of diverse mechanisms, but also proved to be highly sensitive to minor modulations of this crucial contact. Furthermore, our work shows that the contact is not simply mediated by general hydrophobic interactions, but also depends on stereospecific mechanisms.
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Affiliation(s)
- Alexander Korn
- Institute for Medical Physics and Biophysics, Leipzig University, Härtelstr. 16-18, D-04107 Leipzig, Germany
| | - Steffane McLennan
- Institute for Medical Physics and Biophysics, Leipzig University, Härtelstr. 16-18, D-04107 Leipzig, Germany
| | - Juliane Adler
- Institute for Medical Physics and Biophysics, Leipzig University, Härtelstr. 16-18, D-04107 Leipzig, Germany
| | - Martin Krueger
- Institute of Anatomy, Leipzig University, Liebigstr. 13, D-04103 Leipzig, Germany
| | - Dayana Surendran
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005, India
| | - Sudipta Maiti
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005, India
| | - Daniel Huster
- Institute for Medical Physics and Biophysics, Leipzig University, Härtelstr. 16-18, D-04107 Leipzig, Germany
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33
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3D structure determination of amyloid fibrils using solid-state NMR spectroscopy. Methods 2018; 138-139:26-38. [DOI: 10.1016/j.ymeth.2018.03.014] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 03/28/2018] [Accepted: 03/30/2018] [Indexed: 01/08/2023] Open
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34
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Zhang J, Liu J, Zhu Y, Xu Z, Xu J, Wang T, Yu H, Zhang W. Photodynamic micelles for amyloid β degradation and aggregation inhibition. Chem Commun (Camb) 2018; 52:12044-12047. [PMID: 27711295 DOI: 10.1039/c6cc06175c] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Polymeric micelles loaded with chlorin e6 and Tanshinone I (TAS) were prepared and employed for photodegrading amyloid β (Aβ) aggregates and inhibiting Aβ fibrillation.
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Affiliation(s)
- Junying Zhang
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200241, P. R. China.
| | - Jianping Liu
- Center of Pharmaceutics, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Yingying Zhu
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200241, P. R. China.
| | - Zhiai Xu
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200241, P. R. China.
| | - Jie Xu
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200241, P. R. China.
| | - Tingting Wang
- Center of Pharmaceutics, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Haijun Yu
- Center of Pharmaceutics, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Wen Zhang
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200241, P. R. China.
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35
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Chandra B, Maity BK, Das A, Maiti S. Fluorescence quenching by lipid encased nanoparticles shows that amyloid-β has a preferred orientation in the membrane. Chem Commun (Camb) 2018; 54:7750-7753. [DOI: 10.1039/c8cc02108b] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Short range plasmonic fields around a nanoparticle can modulate fluorescence or Raman processes.
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Affiliation(s)
| | | | - Anirban Das
- Tata Institute of Fundamental Research
- Homi Bhabha Road
- Mumbai
- India
| | - Sudipta Maiti
- Tata Institute of Fundamental Research
- Homi Bhabha Road
- Mumbai
- India
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36
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Xiao Y, McElheny D, Hoshi M, Ishii Y. Solid-State NMR Studies of Amyloid Materials: A Protocol to Define an Atomic Model of Aβ(1-42) in Amyloid Fibrils. Methods Mol Biol 2018; 1777:407-428. [PMID: 29744851 DOI: 10.1007/978-1-4939-7811-3_26] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Intense efforts have been made to understand the molecular structures of misfolded amyloid β (Aβ) in order to gain insight into the pathological mechanism of Alzheimer's disease. Solid-state NMR spectroscopy (SSNMR) is considered a primary tool for elucidating the structures of insoluble and noncrystalline amyloid fibrils and other amyloid assemblies. In this chapter, we describe a detailed protocol to obtain the first atomic model of the 42-residue human Aβ peptide Aβ(1-42) in structurally homogeneous amyloid fibrils from our recent SSNMR study (Nat Struct Mol Biol 22:499-505, 2015). Despite great biological and clinical interest in Aβ(1-42) fibrils, their structural details have been long-elusive until this study. The protocol is divided into four sections. First, the solid-phase peptide synthesis (SPPS) and purification of monomeric Aβ(1-42) is described. We illustrate a controlled incubation method to prompt misfolding of Aβ(1-42) into homogeneous amyloid fibrils in an aqueous solution with fragmented Aβ(1-42) fibrils as seeds. Next, we detail analysis of Aβ(1-42) fibrils by SSNMR to obtain structural restraints. Finally, we describe methods to construct atomic models of Aβ(1-42) fibrils based on SSNMR results through two-stage molecular dynamics calculations.
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Affiliation(s)
- Yiling Xiao
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL, USA
| | - Dan McElheny
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL, USA
| | - Minako Hoshi
- Institute of Biomedical Research and Innovation, FBRI, Kobe, Japan
- Department of Anatomy and Developmental Biology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Yoshitaka Ishii
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL, USA.
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan.
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37
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Abstract
Soluble amyloid-β (Aβ) oligomers have become a focal point in the study of Alzheimer's disease due to their ability to elicit cytotoxicity. A number of recent studies have concentrated on the structural characterization of soluble Aβ oligomers to gain insight into their mechanism of toxicity. Consequently, providing reproducible protocols for the preparation of such oligomers is of utmost importance. The method presented in this chapter details a protocol for preparing an Aβ oligomer, with a primarily disordered secondary structure, without the need for chemical modification or amino acid substitution. Due to the stability of these disordered Aβ oligomers and the reproducibility with which they form, they are amenable for biophysical and high-resolution structural characterization.
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Affiliation(s)
- Samuel A Kotler
- Biophysics Program, University of Michigan, Ann Arbor, MI, USA
| | - Ayyalusamy Ramamoorthy
- Biophysics Program, University of Michigan, Ann Arbor, MI, USA.
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA.
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38
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van der Wel PCA. Insights into protein misfolding and aggregation enabled by solid-state NMR spectroscopy. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2017; 88:1-14. [PMID: 29035839 PMCID: PMC5705391 DOI: 10.1016/j.ssnmr.2017.10.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 10/03/2017] [Accepted: 10/03/2017] [Indexed: 05/17/2023]
Abstract
The aggregation of proteins and peptides into a variety of insoluble, and often non-native, aggregated states plays a central role in many devastating diseases. Analogous processes undermine the efficacy of polypeptide-based biological pharmaceuticals, but are also being leveraged in the design of biologically inspired self-assembling materials. This Trends article surveys the essential contributions made by recent solid-state NMR (ssNMR) studies to our understanding of the structural features of polypeptide aggregates, and how such findings are informing our thinking about the molecular mechanisms of misfolding and aggregation. A central focus is on disease-related amyloid fibrils and oligomers involved in neurodegenerative diseases such as Alzheimer's, Parkinson's and Huntington's disease. SSNMR-enabled structural and dynamics-based findings are surveyed, along with a number of resulting emerging themes that appear common to different amyloidogenic proteins, such as their compact alternating short-β-strand/β-arc amyloid core architecture. Concepts, methods, future prospects and challenges are discussed.
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Affiliation(s)
- Patrick C A van der Wel
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15260, USA.
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39
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Hoffmann F, Adler J, Chandra B, Mote KR, Bekçioğlu-Neff G, Sebastiani D, Huster D. Perturbation of the F19-L34 Contact in Amyloid β (1-40) Fibrils Induces Only Local Structural Changes but Abolishes Cytotoxicity. J Phys Chem Lett 2017; 8:4740-4745. [PMID: 28910107 DOI: 10.1021/acs.jpclett.7b02317] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We explored structural details of fibrils formed by a mutated amyloid β (Aβ(1-40)) peptide carrying a Phe19 to Lys19 mutation, which was shown to completely abolish the toxicity of the molecule. Computer models suggest that the positively charged Lys19 side chain is expelled from the hydrophobic fibril interior upon fibrillation. This can be accommodated by either a 180° flip of the entire lower β-strand (model M1) or local perturbations of the secondary structure in the direct vicinity of the mutated site (model M2). This is accompanied by the formation of a new salt bridge between Glu22 and Lys28 in model M1. Experimentally, a novel contact between Phe20 and Leu34 as well as the significant structural perturbation of residues 20-23 could be confirmed. However, the mutated fibrils do not show the formation of any salt bridges. This demonstrates that although morphologically very robust, local perturbations of the Aβ(1-40) sequence lead to moderate structural alterations with tremendous impact on the physiological importance of these aggregates, which may suggest alternative strategies for the development of a remedy against Alzheimer's disease.
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Affiliation(s)
- Felix Hoffmann
- Department of Chemistry, Martin-Luther Universität Halle-Wittenberg , von-Danckelmann-Platz 4, 06120 Halle/Saale, Germany
| | - Juliane Adler
- Institute for Medical Physics and Biophysics, Leipzig University , Härtelstr. 16-18, 04107 Leipzig, Germany
| | - Bappaditya Chandra
- Tata Institute of Fundamental Research , Homi Bhabha Road, Colaba, Mumbai 400 005, India
| | - Kaustubh R Mote
- TIFR Centre for Interdisciplinary Sciences, Tata Institute of Fundamental Research , 21 Brundavan Colony, Narsingi, Hyderabad 500 075, India
| | - Gül Bekçioğlu-Neff
- Department of Chemistry, Martin-Luther Universität Halle-Wittenberg , von-Danckelmann-Platz 4, 06120 Halle/Saale, Germany
| | - Daniel Sebastiani
- Department of Chemistry, Martin-Luther Universität Halle-Wittenberg , von-Danckelmann-Platz 4, 06120 Halle/Saale, Germany
| | - Daniel Huster
- Institute for Medical Physics and Biophysics, Leipzig University , Härtelstr. 16-18, 04107 Leipzig, Germany
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40
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Major Reaction Coordinates Linking Transient Amyloid-β Oligomers to Fibrils Measured at Atomic Level. Biophys J 2017; 113:805-816. [PMID: 28834717 DOI: 10.1016/j.bpj.2017.06.068] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 06/22/2017] [Accepted: 06/22/2017] [Indexed: 11/22/2022] Open
Abstract
The structural underpinnings for the higher toxicity of the oligomeric intermediates of amyloidogenic peptides, compared to the mature fibrils, remain unknown at present. The transient nature and heterogeneity of the oligomers make it difficult to follow their structure. Here, using vibrational and solid-state nuclear magnetic resonance spectroscopy, and molecular dynamics simulations, we show that freely aggregating Aβ40 oligomers in physiological solutions have an intramolecular antiparallel configuration that is distinct from the intermolecular parallel β-sheet structure observed in mature fibrils. The intramolecular hydrogen-bonding network flips nearly 90°, and the two β-strands of each monomeric unit move apart, to give rise to the well-known intermolecular in-register parallel β-sheet structure in the mature fibrils. Solid-state nuclear magnetic resonance distance measurements capture the interstrand separation within monomer units during the transition from the oligomer to the fibril form. We further find that the D23-K28 salt-bridge, a major feature of the Aβ40 fibrils and a focal point of mutations linked to early onset Alzheimer's disease, is not detectable in the small oligomers. Molecular dynamics simulations capture the correlation between changes in the D23-K28 distance and the flipping of the monomer secondary structure between antiparallel and parallel β-sheet architectures. Overall, we propose interstrand separation and salt-bridge formation as key reaction coordinates describing the structural transition of the small Aβ40 oligomers to fibrils.
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41
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Chandra B, Mithu VS, Bhowmik D, Das AK, Sahoo B, Maiti S, Madhu PK. Curcumin Dictates Divergent Fates for the Central Salt Bridges in Amyloid-β 40 and Amyloid-β 42. Biophys J 2017; 112:1597-1608. [PMID: 28445751 DOI: 10.1016/j.bpj.2017.02.043] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 02/02/2017] [Accepted: 02/07/2017] [Indexed: 12/25/2022] Open
Abstract
There are three specific regions in the Amyloid beta (Aβ) peptide sequence where variations cause enhanced toxicity in Alzheimer's disease: the N-terminus, the central salt bridge, and the C-terminus. Here, we investigate if there is a close conformational connection between these three regions, which may suggest a concerted mechanism of toxicity. We measure the effects of Zn2+ and curcumin on Aβ40, and compare these with their previously reported effects on Aβ42. Aβ42 and Aβ40 differ only near the C-terminus, where curcumin interacts, while Zn2+ interacts near the N-terminus. Therefore, this comparison should help us differentiate the effect of modulating the C- and the N-termini. We find that curcumin allows fibril-like structures containing the salt bridge to emerge in the mature Aβ40 aggregates, but not in Aβ42. In contrast, we find no difference in the effects of Zn+2 on Aβ40 and Aβ42. In the presence of Zn+2, both of these fail to form proper fibrils, and the salt bridge remains disrupted. These results indicate that modulations of the Aβ termini can determine the fate of a salt bridge far away in the sequence, and this has significant consequences for Aβ toxicity. We also infer that small molecules can alter oligomer-induced toxicity by modulating the aggregation pathway, without substantially changing the final product of aggregation.
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Affiliation(s)
- Bappaditya Chandra
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai, India
| | | | - Debanjan Bhowmik
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai, India
| | - Anand Kant Das
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai, India
| | - Bankanidhi Sahoo
- TIFR Centre for Interdisciplinary Sciences, Tata Institute of Fundamental Research, Narsinghi, Hyderabad, India
| | - Sudipta Maiti
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai, India.
| | - Perunthiruthy K Madhu
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai, India; TIFR Centre for Interdisciplinary Sciences, Tata Institute of Fundamental Research, Narsinghi, Hyderabad, India.
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42
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Aleksis R, Oleskovs F, Jaudzems K, Pahnke J, Biverstål H. Structural studies of amyloid-β peptides: Unlocking the mechanism of aggregation and the associated toxicity. Biochimie 2017; 140:176-192. [PMID: 28751216 DOI: 10.1016/j.biochi.2017.07.011] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 07/21/2017] [Indexed: 12/31/2022]
Abstract
Alzheimer's disease (AD) is one of the most prevalent neurodegenerative diseases worldwide. Formation of amyloid plaques consisting of amyloid-β peptides (Aβ) is one of the hallmarks of AD. Several lines of evidence have shown a correlation between the Aβ aggregation and the disease development. Extensive research has been conducted with the aim to reveal the structures of the neurotoxic Aβ aggregates. However, the exact structure of pathological aggregates and mechanism of the disease still remains elusive due to complexity of the occurring processes and instability of various disease-relevant Aβ species. In this article we review up-to-date structural knowledge about amyloid-β peptides, focusing on data acquired using solution and solid state NMR techniques. Furthermore, we discuss implications from these structural studies on the mechanisms of aggregation and neurotoxicity.
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Affiliation(s)
- Rihards Aleksis
- Department of Physical Organic Chemistry, Latvian Institute of Organic Synthesis, Aizkraukles 21, Riga, Latvia.
| | - Filips Oleskovs
- Department of Physical Organic Chemistry, Latvian Institute of Organic Synthesis, Aizkraukles 21, Riga, Latvia
| | - Kristaps Jaudzems
- Department of Physical Organic Chemistry, Latvian Institute of Organic Synthesis, Aizkraukles 21, Riga, Latvia
| | - Jens Pahnke
- Department of Neuro-/Pathology, Translational Neurodegeneration Research and Neuropathology Lab, University of Oslo (UiO) & Oslo University Hospital (OUS), Norway; LIED, University of Lübeck Uzl, Germany; Leibniz-Institute of Plant Biochemistry (IPB), Halle, Germany
| | - Henrik Biverstål
- Department of Physical Organic Chemistry, Latvian Institute of Organic Synthesis, Aizkraukles 21, Riga, Latvia; Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Division of Neurogeriatrics, Karolinska Institutet, Stockholm, Sweden
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43
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Chandra B, Halder S, Adler J, Korn A, Huster D, Maiti S. Emerging structural details of transient amyloid-β oligomers suggest designs for effective small molecule modulators. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.02.070] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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44
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Chandra B, Korn A, Maity BK, Adler J, Rawat A, Krueger M, Huster D, Maiti S. Stereoisomers Probe Steric Zippers in Amyloid-β. J Phys Chem B 2017; 121:1835-1842. [PMID: 28140589 DOI: 10.1021/acs.jpcb.6b12332] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Shape complementarity between close-packed residues plays a critical role in the amyloid aggregation process. Here, we probe such "steric zipper" interactions in amyloid-β (Aβ40), whose aggregation is linked to Alzheimer's disease, by replacing natural residues by their stereoisomers. Such mutations are expected to specifically destabilize the shape sensitive "packing" interactions, which may potentially increase their solubility and change other properties. We study the stereomutants DF19 and DL34 and also the DA2/DF4/DH6/DS8 mutant of Aβ40. F19-L34 is a critical contact in a tightly packed region of Aβ, while residues 1-9 are known to be disordered. While both DF19 and DL34 slow down the kinetics of aggregation and form amyloid fibrils efficiently, only DL34 increases the final solubility. DF19 gives rise to additional off-pathway aggregation which results in large, kinetically stable aggregates, and has lower net solubility. DA2/DF4/DH6/DS8 does not have an effect on the kinetics or the solubility. Notably, both DF19 and DL34 oligomers have a significantly lower level of interactions with lipid vesicles and live cells. We conclude that stereoisomers can cause complex site dependent changes in amyloid properties, and provide an effective tool to determine the role of individual residues in shaping the packed interiors of amyloid aggregates.
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Affiliation(s)
- Bappaditya Chandra
- Department of Chemical Science, Tata Institute of Fundamental Research , Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Alexander Korn
- Institut für Medizinische Physik und Biophysik, Universität Leipzig , Härtelstrasse 16-18, D-04107 Leipzig, Germany
| | - Barun Kumar Maity
- Department of Chemical Science, Tata Institute of Fundamental Research , Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Juliane Adler
- Institut für Medizinische Physik und Biophysik, Universität Leipzig , Härtelstrasse 16-18, D-04107 Leipzig, Germany
| | - Anoop Rawat
- Department of Chemical Science, Tata Institute of Fundamental Research , Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Martin Krueger
- Institut für Medizinische Physik und Biophysik, Universität Leipzig , Härtelstrasse 16-18, D-04107 Leipzig, Germany.,Institut für Anatomie, Universität Leipzig , Liebigstr. 13, D-04103 Leipzig, Germany
| | - Daniel Huster
- Institut für Medizinische Physik und Biophysik, Universität Leipzig , Härtelstrasse 16-18, D-04107 Leipzig, Germany
| | - Sudipta Maiti
- Department of Chemical Science, Tata Institute of Fundamental Research , Homi Bhabha Road, Colaba, Mumbai 400005, India
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45
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Chiricotto M, Melchionna S, Derreumaux P, Sterpone F. Hydrodynamic effects on β-amyloid (16-22) peptide aggregation. J Chem Phys 2017; 145:035102. [PMID: 27448906 DOI: 10.1063/1.4958323] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Computer simulations based on simplified representations are routinely used to explore the early steps of amyloid aggregation. However, when protein models with implicit solvent are employed, these simulations miss the effect of solvent induced correlations on the aggregation kinetics and lifetimes of metastable states. In this work, we apply the multi-scale Lattice Boltzmann Molecular Dynamics technique (LBMD) to investigate the initial aggregation phases of the amyloid Aβ16-22 peptide. LBMD includes naturally hydrodynamic interactions (HIs) via a kinetic on-lattice representation of the fluid kinetics. The peptides are represented by the flexible OPEP coarse-grained force field. First, we have tuned the essential parameters that control the coupling between the molecular and fluid evolutions in order to reproduce the experimental diffusivity of elementary species. The method is then deployed to investigate the effect of HIs on the aggregation of 100 and 1000 Aβ16-22 peptides. We show that HIs clearly impact the aggregation process and the fluctuations of the oligomer sizes by favouring the fusion and exchange dynamics of oligomers between aggregates. HIs also guide the growth of the leading largest cluster. For the 100 Aβ16-22 peptide system, the simulation of ∼300 ns allowed us to observe the transition from ellipsoidal assemblies to an elongated and slightly twisted aggregate involving almost the totality of the peptides. For the 1000 Aβ16-22 peptides, a system of unprecedented size at quasi-atomistic resolution, we were able to explore a branched disordered fibril-like structure that has never been described by other computer simulations, but has been observed experimentally.
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Affiliation(s)
- Mara Chiricotto
- Laboratoire de Biochimie Théorique, IBPC, CNRS UPR9080, University Paris Diderot, Sorbonne Paris Cité, 13 rue Pierre et Marie Curie, 75005 Paris, France
| | - Simone Melchionna
- CNR-ISC, Institute for Complex System, Consiglio Nazionale delle Ricerche, Rome, Italy
| | - Philippe Derreumaux
- Laboratoire de Biochimie Théorique, IBPC, CNRS UPR9080, University Paris Diderot, Sorbonne Paris Cité, 13 rue Pierre et Marie Curie, 75005 Paris, France
| | - Fabio Sterpone
- Laboratoire de Biochimie Théorique, IBPC, CNRS UPR9080, University Paris Diderot, Sorbonne Paris Cité, 13 rue Pierre et Marie Curie, 75005 Paris, France
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46
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Awasthi M, Singh S, Pandey VP, Dwivedi UN. Modulation in the conformational and stability attributes of the Alzheimer's disease associated amyloid-beta mutants and their favorable stabilization by curcumin: molecular dynamics simulation analysis. J Biomol Struct Dyn 2017; 36:407-422. [PMID: 28054501 DOI: 10.1080/07391102.2017.1279078] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive accumulation of amyloid-beta (Aβ) peptides in brain. In the present study, two familial Aβ42 mutations, namely A2V (harmful) and A2T (protective) have been analyzed and compared with the wild-type (WT) by performing all-atom molecular dynamics (MD) simulations in the absence and presence of curcumin, a well-known inhibitor of Aβ plaque formation. Mutant A2V was found to exhibit highest stability followed by WT and mutant A2T in the absence of curcumin. This stability trend was found to be reversed in the presence of curcumin, suggesting a significant change in the conformational landscape of Aβ42 folding. Due to significant differences in the folding and interaction patterns of the mutants A2V and A2T, curcumin exhibited higher binding affinity for mutant A2T as compared to that of A2V. To the best of our knowledge, this is the first report on the effect of curcumin binding on structural landscapes of the two contrasting point mutants providing an understanding of the basis of Aβ plaque formation and its prevention by curcumin.
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Affiliation(s)
- Manika Awasthi
- a Bioinformatics Infrastructure Facility, Center of Excellence in Bioinformatics, Department of Biochemistry , University of Lucknow , Lucknow 226007 , India
| | - Swati Singh
- a Bioinformatics Infrastructure Facility, Center of Excellence in Bioinformatics, Department of Biochemistry , University of Lucknow , Lucknow 226007 , India
| | - Veda P Pandey
- a Bioinformatics Infrastructure Facility, Center of Excellence in Bioinformatics, Department of Biochemistry , University of Lucknow , Lucknow 226007 , India
| | - Upendra N Dwivedi
- a Bioinformatics Infrastructure Facility, Center of Excellence in Bioinformatics, Department of Biochemistry , University of Lucknow , Lucknow 226007 , India
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47
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Lendel C, Sparrman T, Mayzel M, Andersson CE, Karlsson G, Härd T. Combined Solution- and Magic Angle Spinning NMR Reveals Regions of Distinct Dynamics in Amyloid β Protofibrils. ChemistrySelect 2016. [DOI: 10.1002/slct.201601468] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Christofer Lendel
- Dept. of Chemistry and Biotechnology; Swedish University of Agricultural Sciences (SLU); Uppsala Sweden
- Dept. of Chemistry - present address; KTH Royal Institute of Technology; Stockholm Sweden
| | | | - Maxim Mayzel
- Swedish NMR Centre; University of Gothenburg; Gothenburg Sweden
| | - C. Evalena Andersson
- Dept. of Chemistry and Biotechnology; Swedish University of Agricultural Sciences (SLU); Uppsala Sweden
- Dept. of Cell and Molecular Biology - present address; Uppsala University; Uppsala Sweden
| | - Göran Karlsson
- Swedish NMR Centre; University of Gothenburg; Gothenburg Sweden
| | - Torleif Härd
- Dept. of Chemistry and Biotechnology; Swedish University of Agricultural Sciences (SLU); Uppsala Sweden
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48
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Fibrils of Truncated Pyroglutamyl-Modified Aβ Peptide Exhibit a Similar Structure as Wildtype Mature Aβ Fibrils. Sci Rep 2016; 6:33531. [PMID: 27650059 PMCID: PMC5030707 DOI: 10.1038/srep33531] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 08/26/2016] [Indexed: 12/03/2022] Open
Abstract
Fibrillation of differently modified amyloid β peptides and deposition as senile plaques are hallmarks of Alzheimer’s disease. N-terminally truncated variants, where the glutamate residue 3 is converted into cyclic pyroglutamate (pGlu), form particularly toxic aggregates. We compare the molecular structure and dynamics of fibrils grown from wildtype Aβ(1–40) and pGlu3-Aβ(3–40) on the single amino acid level. Thioflavin T fluorescence, electron microscopy, and X-ray diffraction reveal the general morphology of the amyloid fibrils. We found good agreement between the 13C and 15N NMR chemical shifts indicative for a similar secondary structure of both fibrils. A well-known interresidual contact between the two β-strands of the Aβ fibrils could be confirmed by the detection of interresidual cross peaks in a 13C-13C NMR correlation spectrum between the side chains of Phe 19 and Leu 34. Small differences in the molecular dynamics of residues in the proximity to the pyroglutamyl-modified N-terminus were observed as measured by DIPSHIFT order parameter experiments.
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49
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Sharma K, Madhu PK, Agarwal V. Systematic evaluation of heteronuclear spin decoupling in solid-state NMR at the rotary-resonance conditions in the regime of fast magic-angle spinning. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 270:136-141. [PMID: 27472380 DOI: 10.1016/j.jmr.2016.07.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 07/15/2016] [Accepted: 07/18/2016] [Indexed: 06/06/2023]
Abstract
The performance of heteronuclear spin decoupling sequences in solid-state NMR severely degrades when the proton radiofrequency (RF) nutation frequencies (ν1) are close to or at multiples of magic-angle spinning (MAS) frequency (νr) that are referred to as rotary-resonance recoupling conditions (ν1=n·νr). Recently, two schemes, namely, PISSARRO and rCW(ApA), have been shown to be less affected by the problem of MAS and RF interference, specifically at the n=2 rotary-resonance recoupling condition, especially in the fast MAS regime. Here, we systematically evaluate the loss in intensity of several heteronuclear spin decoupling sequences at the n=1, 2 conditions compared to high-power decoupling in the fast-MAS regime. We propose that in the fast-MAS regime (above 40kHz) the entire discussion about RF and MAS interference can be avoided by using appropriate low-power decoupling sequences which give comparable performance to decoupling sequences with high-power (1)H irradiation of ca.195kHz.
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Affiliation(s)
- Kshama Sharma
- TIFR Centre for Interdisciplinary Sciences, Tata Institute of Fundamental Research, 21 Brundavan Colony, Narsingi, Hyderabad 500 075, India
| | - P K Madhu
- TIFR Centre for Interdisciplinary Sciences, Tata Institute of Fundamental Research, 21 Brundavan Colony, Narsingi, Hyderabad 500 075, India; Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India.
| | - Vipin Agarwal
- TIFR Centre for Interdisciplinary Sciences, Tata Institute of Fundamental Research, 21 Brundavan Colony, Narsingi, Hyderabad 500 075, India.
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50
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Bleem A, Daggett V. Structural and functional diversity among amyloid proteins: Agents of disease, building blocks of biology, and implications for molecular engineering. Biotechnol Bioeng 2016; 114:7-20. [PMID: 27474784 DOI: 10.1002/bit.26059] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2016] [Revised: 07/25/2016] [Accepted: 07/28/2016] [Indexed: 12/23/2022]
Abstract
Amyloids have long been associated with protein dysfunction and neurodegenerative diseases, but recent research has demonstrated that some organisms utilize the unique properties of the amyloid fold to create functional structures with important roles in biological processes. Additionally, new engineering approaches have taken advantage of amyloid structures for implementation in a wide variety of materials and devices. In this review, the role of amyloid in human disease is discussed and compared to the functional amyloids, which serve a largely structural purpose. We then consider the use of amyloid constructs in engineering applications, including their utility as building blocks for synthetic biology and molecular engineering. Biotechnol. Bioeng. 2017;114: 7-20. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Alissa Bleem
- Department of Bioengineering, University of Washington, Box 355013, Seattle, Washington, 98195-5013
| | - Valerie Daggett
- Department of Bioengineering, University of Washington, Box 355013, Seattle, Washington, 98195-5013
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