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Li JY, Zhou CM, Jin RL, Song JH, Yang KC, Li SL, Tan BH, Li YC. The detection methods currently available for protein aggregation in neurological diseases. J Chem Neuroanat 2024; 138:102420. [PMID: 38626816 DOI: 10.1016/j.jchemneu.2024.102420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Revised: 03/30/2024] [Accepted: 04/13/2024] [Indexed: 04/21/2024]
Abstract
Protein aggregation is a pathological feature in various neurodegenerative diseases and is thought to play a crucial role in the onset and progression of neurological disorders. This pathological phenomenon has attracted increasing attention from researchers, but the underlying mechanism has not been fully elucidated yet. Researchers are increasingly interested in identifying chemicals or methods that can effectively detect protein aggregation or maintain protein stability to prevent aggregation formation. To date, several methods are available for detecting protein aggregates, including fluorescence correlation spectroscopy, electron microscopy, and molecular detection methods. Unfortunately, there is still a lack of methods to observe protein aggregation in situ under a microscope. This article reviews the two main aspects of protein aggregation: the mechanisms and detection methods of protein aggregation. The aim is to provide clues for the development of new methods to study this pathological phenomenon.
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Affiliation(s)
- Jing-Yi Li
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Changchun city, Jilin Province 130021, PR China
| | - Cheng-Mei Zhou
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Changchun city, Jilin Province 130021, PR China
| | - Rui-Lin Jin
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Changchun city, Jilin Province 130021, PR China
| | - Jia-Hui Song
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Changchun city, Jilin Province 130021, PR China; Key Laboratory of Pathobiology, Ministry of Education, Jilin University, Changchun 130021, PR China
| | - Ke-Chao Yang
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Changchun city, Jilin Province 130021, PR China
| | - Shu-Lei Li
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Changchun city, Jilin Province 130021, PR China
| | - Bai-Hong Tan
- Laboratory Teaching Center of Basic Medicine, Norman Bethune Health Science Center of Jilin University, Changchun city, Jilin Province 130021, PR China
| | - Yan-Chao Li
- Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Changchun city, Jilin Province 130021, PR China; Key Laboratory of Pathobiology, Ministry of Education, Jilin University, Changchun 130021, PR China.
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2
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Ji W, Hu Y, Wang X, Zhao J, He Y, Zhu Z, Rao J. Biomimetic protein structural transitions regulate activation and inhibition of the broad-spectrum bactericidal activity of cationic nanoparticles. Acta Biomater 2024; 182:156-170. [PMID: 38750919 DOI: 10.1016/j.actbio.2024.05.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 05/01/2024] [Accepted: 05/09/2024] [Indexed: 06/02/2024]
Abstract
The development of cationic polymers as alternative materials to antibiotics necessitates addressing the challenge of balancing their antimicrobial activity and toxicity. Here we propose a precise switching strategy inspired by biomimetic voltage-gated ion channels, enabling controlled activation and inhibition of cationic antimicrobial functions through protein conformational transitions in diverse physiological environments. Following thermodynamic studies on the specific recognition between mannose end groups on polycations and concanavalin A (ConA), we synthesized a type of ConA-polycation nanoparticle. The nanoparticle was inhibited under neutral conditions, with cationic moieties shielded by ConA's β-sheet. This shielding suppresses their antimicrobial activity, thereby ensuring satisfactory biocompatibility. In mildly acidic environments, however, the transition of a portion of ConA to an α-helix conformation exposed cations at the particle periphery, activating antibacterial functionality. Compared to inhibited nanoparticles, those in the activated state exhibited a 32-256 times reduction in the minimum bactericidal concentration against bacteria and fungi (2-16 µg/mL). In a murine acute pulmonary infection model, intravenous administration of inhibited nanoparticles effectively reduced bacterial counts by 4-log within 12 h. The biomimetic design, regulating cationic antimicrobial functionality through the alteration in protein secondary structure, significantly retards bacterial resistance development, holding great promise for intelligent antimicrobial materials. STATEMENT OF SIGNIFICANCE: Cationic antimicrobial polymers exhibit advantages distinct from antibiotics due to their lower propensity for resistance development. However, the presence of cationic moieties also poses a threat to healthy cells and tissues, significantly constraining their potential for clinical applications. To address this challenge, we propose a biomimetic strategy that mimics voltage-gated ion channels to activate the antimicrobial functionality of cations selectively in bacterial environments through the conformational transitions of proteins between β-sheets and α-helices. In healthy tissues, the antimicrobial functionality is inhibited, ensuring satisfactory biocompatibility. Antimicrobial cationic materials capable of intelligent switching between an activated state and an inhibited state in response to environmental changes offer an effective strategy to prevent the development of resistance and mitigate potential side effects.
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Affiliation(s)
- Wenke Ji
- Hubei Key Laboratory of Material Chemistry and Service Failure, Hubei Engineering Research Center for Biomaterials and Medical Protective Materials, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, PR China
| | - Yongjin Hu
- Hubei Key Laboratory of Material Chemistry and Service Failure, Hubei Engineering Research Center for Biomaterials and Medical Protective Materials, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, PR China
| | - Xiao Wang
- Hubei Key Laboratory of Material Chemistry and Service Failure, Hubei Engineering Research Center for Biomaterials and Medical Protective Materials, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, PR China
| | - Jinghua Zhao
- Hubei Key Laboratory of Material Chemistry and Service Failure, Hubei Engineering Research Center for Biomaterials and Medical Protective Materials, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, PR China
| | - Yan He
- Department of Pharmacy, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, PR China
| | - Zhiyuan Zhu
- Taizhou Research Institute, Southern University of Science and Technology, Taizhou, Zhejiang, 318001, PR China
| | - Jingyi Rao
- Hubei Key Laboratory of Material Chemistry and Service Failure, Hubei Engineering Research Center for Biomaterials and Medical Protective Materials, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, PR China.
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Ansari NK, Rais A, Naeem A. Methotrexate for Drug Repurposing as an Anti-Aggregatory Agent to Mercuric Treated α-Chymotrypsinogen-A. Protein J 2024; 43:362-374. [PMID: 38431536 DOI: 10.1007/s10930-024-10187-z] [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] [Accepted: 02/24/2024] [Indexed: 03/05/2024]
Abstract
Protein aggregation is related to numerous pathological conditions like Alzheimer's and Parkinson's disease. In our study, we have shown that an already existing FDA-approved drug; methotrexate (MTX) can be reprofiled on preformed α-chymotrypsinogen A (α-Cgn A) aggregates. The zymogen showed formation of aggregates upon interaction with mercuric ions, with increasing concentration of Hg2Cl2 (0-150 µM). The hike in ThT and ANS fluorescence concomitant with blue shift, bathochromic shift and the hyperchromic effect in the CR absorbance, RLS and turbidity measurements, substantiate the zymogen β-rich aggregate formation. The secondary structural alterations of α- Cgn A as analyzed by CD measurements, FTIR and Raman spectra showed the transformation of native β-barrel conformation to β-inter-molecular rich aggregates. The native α- Cgn A have about 30% α-helical content which was found to be about 3% in presence of mercuric ions suggesting the formation of aggregates. The amorphous aggregates were visualized by SEM. On incubation of Hg2Cl2 treated α- Cgn A with increasing concentration of the MTX resulted in reversing aggregates to the native-like structure. These results were supported by remarkable decrease in ThT and ANS fluorescence intensities and CR absorbance and also consistent with CD, FTIR, and Raman spectroscopy data. MTX was found to increase the α-helical content of the zymogen from 3 to 15% proposing that drug is efficient in disrupting the β-inter-molecular rich aggregates and reverting it to native like structure. The SEM images are in accordance with CD data showing the disintegration of aggregates. The most effective concentration of the drug was found to be 120 µM. Molecular docking analysis showed that MTX molecule was surrounded by the hydrophobic residues including Phe39, His40, Arg145, Tyr146, Thr151, Gly193, Ser195, and Gly216 and conventional hydrogen bonds, including Gln73 (bond length: 2.67Å), Gly142 (2.59Å), Thr144 (2.81Å), Asn150 (2.73Å), Asp153 (2.71Å), and Cys191 (2.53Å). This investigation will help to find the use of already existing drugs to cure protein misfolding-related abnormalities.
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Affiliation(s)
- Neha Kausar Ansari
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, U.P, 202002, India
| | - Amaan Rais
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, U.P, 202002, India
| | - Aabgeena Naeem
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, U.P, 202002, India.
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Sheng Y, Li Z, Lin X, Ma Y, Ren Y, Su Z, Ma G, Zhang S. The position of Spy Tag/Catcher system in hepatitis B core protein particles affects the immunogenicity and stability of the synthetic vaccine. Vaccine 2023:S0264-410X(23)00759-4. [PMID: 37391312 DOI: 10.1016/j.vaccine.2023.06.070] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 06/20/2023] [Accepted: 06/22/2023] [Indexed: 07/02/2023]
Abstract
Presenting exogenous antigens on virus-like particles (VLPs) through "plug-and-display" decoration strategies based on SpyTag/SpyCatcher isopeptide bonding have emerged as attractive technology for vaccine synthesis. However, whether the position of ligation site in VLPs will impose effects on immunogenicity and physiochemical properties of the synthetic vaccine remains rarely investigated. Here in the present work, the well-established hepatitis B core (HBc) protein was used as chassis to construct dual-antigen influenza nanovaccines, with the conserved epitope peptides derived from extracellular domain of matrix protein M2 (M2e) and hemagglutinin (HA) as target antigens. The M2e antigen was genetically fused to the HBc in the MIR region, together with the SpyTag peptide, which was fused either in the MIR region or at the N-terminal of the protein, so that a recombinant HA antigen (rHA) linked to SpyCatcher can be displayed on it, at two different localizations. Both synthetic nanovaccines showed ability in inducing strong M2e and rHA-specific antibodies and cellular immunogenicity; nevertheless, the one in which rHA was conjugated by N-terminal Tag ligation, was superior to another one synthesized by linking the rHA to MIR region SpyTagged-HBc in all aspects, including higher antigen-specific immunogenicity responses, lower anti-HBc carrier antibody, as well as better dispersion stability. Surface charge and hydrophobicity properties of the two synthetic nanovaccines were analyzed, results revealed that linking the rHA to MIR region SpyTagged-HBc lead to more significant and disadvantageous alteration in physiochemical properties of the HBc chassis. This study will expand our knowledge on "plug-and-display" decoration strategies and provide helpful guidance for the rational design of HBc-VLPs based modular vaccines by using SpyTag/Catcher synthesis.
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Affiliation(s)
- Yanan Sheng
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhengjun Li
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Xuan Lin
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Yanyan Ma
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Ying Ren
- State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; School of Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhiguo Su
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Guanghui Ma
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Songping Zhang
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
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Khan JM, Malik A, Alresaini SM. Molecular mechanism of insulin aggregation in the presence of a cationic surfactant. Int J Biol Macromol 2023; 230:123370. [PMID: 36693606 DOI: 10.1016/j.ijbiomac.2023.123370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 01/16/2023] [Accepted: 01/17/2023] [Indexed: 01/22/2023]
Abstract
Protein aggregation and amyloid fibrillation are connected with neurodegenerative disorders. Insulin, a small molecular weight protein related to type II diabetes, has been shown to self-assemble to form protein aggregates. In this work, we investigated the effects of cetyltrimethylammonium bromide (CTAB) of insulin on the in vitro aggregation process at pH 7.4 and 2.0. The aggregation tendency of insulin was measured using a variety of biophysical approaches, including turbidity measurements, light scattering, far UV-CD, ThT dye binding, and transmission electron microscopy. The turbidity results demonstrated that at pH 7.4, a low concentration of CTAB (30-180 μM) causes insulin aggregation but at higer concentration (>180 μM) aggregation was not seen. However, at pH 2.0, both low as well as high concentrations of CTAB were unable to promote insulin aggregation. The ThT dye binding and far-UV CD data suggest that aggregation induced by CTAB is not having an ordered structure. Insulin treated with higher concentrations (>180 μM) of CTAB, the insulin gained a secondary structure. The possible cause of inducing aggregation in insulin is electrostatic and hydrophobic interaction because insulin contains a net negative charge at pH 7.4 and no aggregation at pH 2.0 due to electrostatic repulsion.
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Affiliation(s)
- Javed Masood Khan
- Department of Food Science and Nutrition, College of Food and Agricultural Sciences, King Saud University, 2460, Riyadh 11451, Saudi Arabia.
| | - Ajamaluddin Malik
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
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Tomaino E, Capecchi E, Piccinino D, Saladino R. Lignin nanoparticles support lipase‐tyrosinase enzymatic cascade in the synthesis of lipophilic hydroxytyrosol ester derivatives. ChemCatChem 2022. [DOI: 10.1002/cctc.202200380] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Elisabetta Tomaino
- University of Tuscia: Universita degli Studi della Tuscia Department of Biological and Ecological Sciences Via S.C De Lellis s.n.c. 01100 Viterbo ITALY
| | - Eliana Capecchi
- University of Tuscia: Universita degli Studi della Tuscia Department of Biological and Ecological Sciences Via S.C. De Lellis s.n.c. 01100 Viterbo ITALY
| | - Davide Piccinino
- University of Tuscia: Universita degli Studi della Tuscia Department of Biological and Ecological Sciences 01100 Viterbo ITALY
| | - Raffaele Saladino
- University of Tuscia: Universita degli Studi della Tuscia Department of Biological and Ecological Sciences Via S. Camillo de Lellis 00100 Viterbo ITALY
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7
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Phenylalanine and indole effects on the pathogenicity of human lysozyme amorphous aggregates. Enzyme Microb Technol 2022; 158:110036. [DOI: 10.1016/j.enzmictec.2022.110036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 03/20/2022] [Accepted: 03/24/2022] [Indexed: 11/20/2022]
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Khan JM, Malik A, Ahmed MZ, Ahmed A. SDS modulates amyloid fibril formation and conformational change in succinyl-ConA at low pH. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 267:120494. [PMID: 34689006 DOI: 10.1016/j.saa.2021.120494] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 10/04/2021] [Accepted: 10/08/2021] [Indexed: 06/13/2023]
Abstract
The anionic surfactant sodium dodecyl sulfate (SDS) is homologous to the cellular membrane lipids, and is known to stimulate amyloid fibrillation in several proteins. However, the mechanism by which SDS influences aggregation and structural changes in succinylated protein has not been determined. In this study, we observed the effects of variable SDS concentrations on succinyl-ConA aggregation at pH 3.5 and proposed a possible mechanism of SDS-induced succinyl-ConA aggregation. We used several biophysical techniques to identify the changes caused by SDS. Our results suggest that SDS stimulates succinyl-ConA aggregation in a concentration-dependent manner. From turbidity measurements, it was evident that a very low concentration (<0.1 mM) of SDS did not induce succinyl-ConA aggregation and proteins remained soluble. However, aggregations were observed at 0.1-2.5 mM SDS, which then dissipated at SDS concentrations above 2.5 mM. Far-UV CD results suggest that the β-sheet secondary structure of succinyl-ConA transformed into the cross-β-sheet structure in the presence of aggregating SDS concentrations. Notably, at SDS concentrations above 2.5 mM, the succinyl-ConA β-sheet transformed into an α-helical structure. The SDS-induced succinyl-ConA amyloid-like aggregates were confirmed by transmission electron microscopy (TEM). We propose that SDS modulates amyloid fibrillation in succinyl-ConA due to electrostatic and hydrophobic interactions and succinylation affects SDS-induced succinyl-ConA aggregation.
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Affiliation(s)
- Javed Masood Khan
- Department of Food Science and Nutrition, Faculty of Food and Agricultural Sciences, King Saud University, 2460, Riyadh 11451, Saudi Arabia.
| | - Ajamaluddin Malik
- Department of Biochemistry, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - Mohammad Z Ahmed
- Department of Pharmacognosy, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Anwar Ahmed
- Department of Biochemistry, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
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Lendel C, Solin N. Protein nanofibrils and their use as building blocks of sustainable materials. RSC Adv 2021; 11:39188-39215. [PMID: 35492452 PMCID: PMC9044473 DOI: 10.1039/d1ra06878d] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 11/25/2021] [Indexed: 12/21/2022] Open
Abstract
The development towards a sustainable society requires a radical change of many of the materials we currently use. Besides the replacement of plastics, derived from petrochemical sources, with renewable alternatives, we will also need functional materials for applications in areas ranging from green energy and environmental remediation to smart foods. Proteins could, with their intriguing ability of self-assembly into various forms, play important roles in all these fields. To achieve that, the code for how to assemble hierarchically ordered structures similar to the protein materials found in nature must be cracked. During the last decade it has been demonstrated that amyloid-like protein nanofibrils (PNFs) could be a steppingstone for this task. PNFs are formed by self-assembly in water from a range of proteins, including plant resources and industrial side streams. The nanofibrils display distinct functional features and can be further assembled into larger structures. PNFs thus provide a framework for creating ordered, functional structures from the atomic level up to the macroscale. This review address how industrial scale protein resources could be transformed into PNFs and further assembled into materials with specific mechanical and functional properties. We describe what is required from a protein to form PNFs and how the structural properties at different length scales determine the material properties. We also discuss potential chemical routes to modify the properties of the fibrils and to assemble them into macroscopic structures.
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Affiliation(s)
- Christofer Lendel
- Department of Chemistry, KTH Royal Institute of Technology Teknikringen 30 SE-100 44 Stockholm Sweden
| | - Niclas Solin
- Department of Physics, Chemistry, and Biology, Electronic and Photonic Materials, Biomolecular and Organic Electronics, Linköping University Linköping 581 83 Sweden
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Hsueh SS, Lu JH, Wu JW, Lin TH, Wang SSS. Protection of human γD-crystallin protein from ultraviolet C-induced aggregation by ortho-vanillin. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2021; 261:120023. [PMID: 34098480 DOI: 10.1016/j.saa.2021.120023] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 05/20/2021] [Accepted: 05/24/2021] [Indexed: 06/12/2023]
Abstract
Cataract is known as one of the leading causes of vision impairment worldwide. While the detailed mechanism of cataratogenesis remains unclear, cataract is believed to be correlated with the aggregation and/or misfolding of human ocular lens proteins called crystallins. A 173-residue structural protein human γD-crystallin is a major γ-crystallin protein in the human eye lens and associated with the development of juvenile and mature-onset cataracts. This work is aimed at investigating the effect of a small molecule, e.g., ortho-vanillin, on human γD-crystallin aggregation upon exposure to ultraviolet-C irradiation. According to the findings of right-angle light scattering, transmission electron microscopy, and gel electrophoresis, ortho-vanillin was demonstrated to dose-dependently suppress ultraviolet-C-triggered aggregation of human γD-crystallin. Results from the synchronous fluorescence spectroscopy, tryptophan fluorescence quenching, and molecular docking studies revealed the structural change of γD-crystallin induced by the interaction/binding between ortho-vanillin and protein. We believe the outcome from this work may contribute to the development of potential therapeutics for cataract.
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Affiliation(s)
- Shu-Shun Hsueh
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Jian-Hong Lu
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Josephine W Wu
- Department of Optometry, Yuanpei University of Medical Technology, Hsinchu City 30015, Taiwan.
| | - Ta-Hsien Lin
- Basic Research Division, Medical Research Department, Taipei Veterans General Hospital, Taipei 11217, Taiwan; Institute of Biochemistry and Molecular Biology, National Yang Ming Chiao Tung University, Taipei 11221, Taiwan.
| | - Steven S-S Wang
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan.
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11
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Garfagnini T, Levi-Kalisman Y, Harries D, Friedler A. Osmolytes and crowders regulate aggregation of the cancer-related L106R mutant of the Axin protein. Biophys J 2021; 120:3455-3469. [PMID: 34087214 DOI: 10.1016/j.bpj.2021.05.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Accepted: 05/28/2021] [Indexed: 11/16/2022] Open
Abstract
Protein aggregation is involved in a variety of diseases, including neurodegenerative diseases and cancer. The cellular environment is crowded by a plethora of cosolutes comprising small molecules and biomacromolecules at high concentrations, which may influence the aggregation of proteins in vivo. To account for the effect of cosolutes on cancer-related protein aggregation, we studied their effect on the aggregation of the cancer-related L106R mutant of the Axin protein. Axin is a key player in the Wnt signaling pathway, and the L106R mutation in its RGS domain results in a native molten globule that tends to form native-like aggregates. This results in uncontrolled activation of the Wnt signaling pathway, leading to cancer. We monitored the aggregation process of Axin RGS L106R in vitro in the presence of a wide ensemble of cosolutes including polyols, amino acids, betaine, and polyethylene glycol crowders. Except myo-inositol, all polyols decreased RGS L106R aggregation, with carbohydrates exerting the strongest inhibition. Conversely, betaine and polyethylene glycols enhanced aggregation. These results are consistent with the reported effects of osmolytes and crowders on the stability of molten globular proteins and with both amorphous and amyloid aggregation mechanisms. We suggest a model of Axin L106R aggregation in vivo, whereby molecularly small osmolytes keep the protein as a free soluble molecule but the increased crowding of the bound state by macromolecules induces its aggregation at the nanoscale. To our knowledge, this is the first systematic study on the effect of osmolytes and crowders on a process of native-like aggregation involved in pathology, as it sheds light on the contribution of cosolutes to the onset of cancer as a protein misfolding disease and on the relevance of aggregation in the molecular etiology of cancer.
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Affiliation(s)
- Tommaso Garfagnini
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Yael Levi-Kalisman
- The Harvey M. Krueger Family Center for Nanoscience and Nanotechnology and The Alexander Silberman Life Sciences Institute, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Daniel Harries
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel; The Fritz Haber Center, The Hebrew University of Jerusalem, Jerusalem, Israel.
| | - Assaf Friedler
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel.
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12
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Desai AM, Pandey SP, Singh PK. Effect of counter-anions on the aggregation of Thioflavin-T. Phys Chem Chem Phys 2021; 23:9948-9961. [PMID: 33861224 DOI: 10.1039/d1cp00193k] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The aggregation of small molecules in aqueous solution is known to be influenced by the ionic strength of the medium; however, the role played by the identity of salt in the phenomenon of small molecule aggregation is rarely investigated. In the present contribution, we have investigated the effect of counter-anions on the aggregation of a popular cationic amyloid sensing probe, Thioflavin-T (ThT), by taking six different anions, viz. chloride, bromide, acetate, iodide, tetrafluoroborate, and perchlorate. Our results clearly indicate that it is not the ionic strength of the medium which solely controls aggregation of small molecules but distinct ions behave distinctly with regard to the organization. In fact, distinct ion effects play a major role in the salt induced organization of fluorophores. Using detailed steady-state emission, time-resolved emission, and ground-state absorption measurements, the optical properties of salt induced aggregates of ThT have been characterized. We have rationalized our observations on the basis of the theory of matching water affinity, which suggests that the matching free hydration energy is a critical aspect for the formation of contact ion pairs, which eventually results in aggregation. In brief, a larger sized anion, perchlorate, has a lower free energy of hydration and forms a suitable contact ion pair, with a larger organic cation, ThT, having weaker hydration. This contact ion-pair formation subsequently leads to the formation of an aggregate assembly which is found to be emissive in nature. Therefore, it is possible to induce aggregation of ThT by selecting the right counterion with the appropriate size, which may help us to evaluate the false positive signals when high ionic strength and specific counterions are present in the sensing matrix.
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Affiliation(s)
- Akshat M Desai
- Radiation & Photochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India.
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Amyloid Aggregates of Smooth-Muscle Titin Impair Cell Adhesion. Int J Mol Sci 2021; 22:ijms22094579. [PMID: 33925514 PMCID: PMC8123791 DOI: 10.3390/ijms22094579] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/21/2021] [Accepted: 04/24/2021] [Indexed: 11/17/2022] Open
Abstract
Various amyloid aggregates, in particular, aggregates of amyloid β-proteins, demonstrate in vitro and in vivo cytotoxic effects associated with impairment of cell adhesion. We investigated the effect of amyloid aggregates of smooth-muscle titin on smooth-muscle-cell cultures. The aggregates were shown to impair cell adhesion, which was accompanied by disorganization of the actin cytoskeleton, formation of filopodia, lamellipodia, and stress fibers. Cells died after a 72-h contact with the amyloid aggregates. To understand the causes of impairment, we studied the effect of the microtopology of a titin-amyloid-aggregate-coated surface on fibroblast adhesion by atomic force microscopy. The calculated surface roughness values varied from 2.7 to 4.9 nm, which can be a cause of highly antiadhesive properties of this surface. As all amyloids have the similar structure and properties, it is quite likely that the antiadhesive effect is also intrinsic to amyloid aggregates of other proteins. These results are important for understanding the mechanisms of the negative effect of amyloids on cell adhesion.
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14
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Feng Y, Liu W, Mercadé-Prieto R, Chen XD. Dye-protein interactions between Rhodamine B and whey proteins that affect the photoproperties of the dye. J Photochem Photobiol A Chem 2021. [DOI: 10.1016/j.jphotochem.2020.113092] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Chiang YL, Chang YJ, Chen YR, Hwang IS. Effects of Dissolved Gases on the Amyloid Fibril Morphology. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:516-523. [PMID: 33352048 DOI: 10.1021/acs.langmuir.0c03215] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The onset or progression of numerous neurodegenerative diseases occurs due to aggregation of proteins that ultimately form fibrils. The assembly and morphology of fibrils are susceptible to environmental factors. In this work, we used atomic force microscopy (AFM) to investigate the effects of dissolved nitrogen and oxygen molecules on the morphology of fibrils formed by a hydrophobic amyloid peptide implicated in amyotrophic lateral sclerosis, 15 repeats of glycine-alanine, on a highly oriented pyrolytic graphite substrate. We started with preformed fibril solutions that were then diluted with buffers of different gas conditions, resulting in the aggregation of the fibrils into different morphologies that were revealed by AFM after adsorption on the substrate. Straight fibrils were observed in both degassed and ambient buffers, but a stronger lateral association was seen in degassed buffers. Smaller and softer fibrils were observed in O2-supersaturated buffers, and plaque-like fibril aggregates of considerably large size were evident in N2-supersaturated buffers. In overnight incubation experiments, we observed changes in both the morphology and height of the fibril aggregates, and their evolution varied with different gas conditions. These findings indicate that the gas type and concentration affect the aggregation of amyloid fibrils and may facilitate the development of biomaterial applications and treatments for amyloid-related diseases.
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Affiliation(s)
- Ya-Ling Chiang
- Institute of Physics, Academia Sinica, Nankang, Taipei 115, Taiwan
| | - Yu-Jen Chang
- Genomics Research Center, Academia Sinica, Taipei 115, Taiwan
- Taiwan International Graduate Program in Interdisciplinary Neuroscience, National Taiwan University and Academia Sinica, Taipei, 115, Taiwan
| | - Yun-Ru Chen
- Genomics Research Center, Academia Sinica, Taipei 115, Taiwan
- Taiwan International Graduate Program in Interdisciplinary Neuroscience, National Taiwan University and Academia Sinica, Taipei, 115, Taiwan
| | - Ing-Shouh Hwang
- Institute of Physics, Academia Sinica, Nankang, Taipei 115, Taiwan
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Khan JM, Malik A, Ahmed A, Alghamdi OHA, Ahmed M. SDS induces cross beta-sheet amyloid as well as alpha-helical structure in conconavalin A. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.114154] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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17
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Parveen R, Tarannum Z, Ali S, Fatima S. Nanoclay based study on protein stability and aggregation and its implication in human health. Int J Biol Macromol 2020; 166:385-400. [PMID: 33122071 DOI: 10.1016/j.ijbiomac.2020.10.197] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 10/09/2020] [Accepted: 10/24/2020] [Indexed: 10/23/2022]
Abstract
Protein aggregation is the major cause of several acute amyloid diseases such as Parkinson's, Huntington's, Alzheimer's, Lysozyme Systemic amyloidosis, Diabetes-II etc. While these diseases have attracted much attention but the cure is still unavailable. In the present study, Human Serum Albumin (HSA) and Human Lysozyme (HL) were used as the model proteins to investigate their aggregations. Nanoclays are hydrous silicates found in clay fraction of soil and known as natural nanomaterials. They have long been used in several applications in health-related products. In the present paper, the different types of nanoclays (MMT K-10, MMT K-30, Halloysite, Bentonite) were used to inhibit the process of HSA and HL aggregation. Aggregation experiments were evaluated using several biophysical tools such as Turbidity measurements, Intrinsic fluorescence, 1-anilino-8-naphthalene sulfonate (ANS), Thioflavin T (Th T), congo red (CR) binding assays and Circular dichroism. Results demonstrated that all the nanoclays inhibit the DTT-induced aggregation. However, bentonite and MMT K-10 were progressively intense and potent as they slowed down nucleation stage which can be perceived using several biophysical techniques. Hence, nanoclays can be used as an artificial chaperone and might provide effective treatment against several protein aggregation related disorders.
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Affiliation(s)
- Romana Parveen
- Department of Biotechnology, Jamia Millia Islamia, New Delhi 110025, India
| | - Zeba Tarannum
- Department of Biotechnology, Jamia Millia Islamia, New Delhi 110025, India
| | - Sher Ali
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi 110025, India
| | - Sadaf Fatima
- Department of Biotechnology, Jamia Millia Islamia, New Delhi 110025, India.
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Abstract
Nanoscale optical labeling is an advanced bioimaging tool. It is mostly based on fluorescence (FL) phenomena and enables the visualization of single biocells, bacteria, viruses, and biological tissues, providing monitoring of functional biosystems in vitro and in vivo, and the imaging-guided transportation of drug molecules. There is a variety of FL biolabels such as organic molecular dyes, genetically encoded fluorescent proteins (green fluorescent protein and homologs), semiconductor quantum dots, carbon dots, plasmonic metal gold-based nanostructures and more. In this review, a new generation of FL biolabels based on the recently found biophotonic effects of visible FL are described. This intrinsic FL phenomenon is observed in any peptide/protein materials folded into β-sheet secondary structures, irrespective of their composition, complexity, and origin. The FL effect has been observed both in natural amyloid fibrils, associated with neurodegenerative diseases (Alzheimer’s, Parkinson’s, and more), and diverse synthetic peptide/protein structures subjected to thermally induced biological refolding helix-like→β-sheet. This approach allowed us to develop a new generation of FL peptide/protein bionanodots radiating multicolor, tunable, visible FL, covering the entire visible spectrum in the range of 400–700 nm. Newly developed biocompatible nanoscale biomarkers are considered as a promising tool for emerging precise biomedicine and advanced medical nanotechnologies (high-resolution bioimaging, light diagnostics, therapy, optogenetics, and health monitoring).
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Computational prediction of protein aggregation: Advances in proteomics, conformation-specific algorithms and biotechnological applications. Comput Struct Biotechnol J 2020; 18:1403-1413. [PMID: 32637039 PMCID: PMC7322485 DOI: 10.1016/j.csbj.2020.05.026] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 05/26/2020] [Accepted: 05/28/2020] [Indexed: 12/16/2022] Open
Abstract
Protein aggregation is a widespread phenomenon that stems from the establishment of non-native intermolecular contacts resulting in protein precipitation. Despite its deleterious impact on fitness, protein aggregation is a generic property of polypeptide chains, indissociable from protein structure and function. Protein aggregation is behind the onset of neurodegenerative disorders and one of the serious obstacles in the production of protein-based therapeutics. The development of computational tools opened a new avenue to rationalize this phenomenon, enabling prediction of the aggregation propensity of individual proteins as well as proteome-wide analysis. These studies spotted aggregation as a major force driving protein evolution. Actual algorithms work on both protein sequences and structures, some of them accounting also for conformational fluctuations around the native state and the protein microenvironment. This toolbox allows to delineate conformation-specific routines to assist in the identification of aggregation-prone regions and to guide the optimization of more soluble and stable biotherapeutics. Here we review how the advent of predictive tools has change the way we think and address protein aggregation.
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20
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Sancataldo G, Anselmo S, Vetri V. Phasor-FLIM analysis of Thioflavin T self-quenching in Concanavalin amyloid fibrils. Microsc Res Tech 2020; 83:811-816. [PMID: 32180304 DOI: 10.1002/jemt.23472] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 02/28/2020] [Indexed: 12/20/2022]
Abstract
The formation of amyloid structures has traditionally been related to human neurodegenerative pathologies and, in recent years, the interest in these highly stable nanostructures was extended to biomaterial sciences. A common method to monitor amyloid growth is the analysis of Thioflavin T fluorescence. The use of this highly selective dye, diffused worldwide, allows mechanistic studies of supramolecular assemblies also giving back important insight on the structure of these aggregates. Here we present experimental evidence of self-quenching effect of Thioflavin T in presence of amyloid fibrils. A significant reduction of fluorescence lifetime of this dye which is not related to the properties of analyzed amyloid structures is found. This result is achieved by coupling Fluorescence Lifetime Imaging Microscopy with phasor approach as suitable model-free methods and constitute a serious warning that have to be taken in account if is dye is used for quantitative studies.
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Affiliation(s)
- Giuseppe Sancataldo
- Dipartimento di Fisica e Chimica - E. Segrè, Università di Palermo, Palermo, Italy
| | - Sara Anselmo
- Dipartimento di Fisica e Chimica - E. Segrè, Università di Palermo, Palermo, Italy
| | - Valeria Vetri
- Dipartimento di Fisica e Chimica - E. Segrè, Università di Palermo, Palermo, Italy
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21
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Zhao S, Shi C, Hu H, Li Z, Xiao G, Yang Q, Sun P, Cheng L, Niu W, Bi J, Yue Z. ISFET and Dex-AgNPs based portable sensor for reusable and real-time determinations of concanavalin A and glucose on smartphone. Biosens Bioelectron 2020; 151:111962. [PMID: 31999575 DOI: 10.1016/j.bios.2019.111962] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 12/08/2019] [Accepted: 12/11/2019] [Indexed: 02/06/2023]
Abstract
In this paper, a portable real-time sensing device was built for Concanavalin A (Con A) and glucose detection using a smartphone. The ion-sensitive field-effect transistor (ISFET) functioning at a low working point was selected as a small-size, low-power transducer, and dextran-capped silver nanoparticles (Dex-AgNPs) served as sensitive nanoprobes on the ISFET gate. Using the affinity between Con A and carbohydrates, Con A can be captured, and thus directly detected by the ISFET/Dex-AgNPs unit; then glucose can be determined indirectly by removing Con A from the ISFET/Dex-AgNPs/Con A unit via competition with dextran. The mechanism of this competition does less harm to the sensor, allows the reusability of the sensing device, and overcomes the Debye screening of the FET device in saline solutions. Powered by a button cell, the handheld device attains excellent Con A (0.16 ng mL-1) and glucose (10 nM) detection limit, and can practically be used for at least 20 days.
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Affiliation(s)
- Shuang Zhao
- Department of Microelectronics, Nankai University, Tianjin, 300350, PR China
| | - Cong Shi
- Department of Microelectronics, Nankai University, Tianjin, 300350, PR China
| | - Hongyang Hu
- Department of Microelectronics, Nankai University, Tianjin, 300350, PR China; Key Laboratory of Microelectronic Devices & Integrated Technology, Institute of Microelectronics, Chinese Academy of Sciences, Beijing, 10010, PR China
| | - Zhengping Li
- Department of Microelectronics, Nankai University, Tianjin, 300350, PR China
| | - Gang Xiao
- Department of Microelectronics, Nankai University, Tianjin, 300350, PR China
| | - Qiaochun Yang
- Department of Microelectronics, Nankai University, Tianjin, 300350, PR China
| | - Peng Sun
- Department of Microelectronics, Nankai University, Tianjin, 300350, PR China
| | - Linyang Cheng
- Department of Microelectronics, Nankai University, Tianjin, 300350, PR China
| | - Wencheng Niu
- Department of Microelectronics, Nankai University, Tianjin, 300350, PR China
| | - Jinshun Bi
- Key Laboratory of Microelectronic Devices & Integrated Technology, Institute of Microelectronics, Chinese Academy of Sciences, Beijing, 10010, PR China.
| | - Zhao Yue
- Department of Microelectronics, Nankai University, Tianjin, 300350, PR China; Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, Tianjin, 300350, PR China.
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22
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Sulatsky MI, Sulatskaya AI, Stepanenko OV, Povarova OI, Kuznetsova IM, Turoverov KK. Denaturant effect on amyloid fibrils: Declasterization, depolymerization, denaturation and reassembly. Int J Biol Macromol 2020; 150:681-694. [PMID: 32057863 DOI: 10.1016/j.ijbiomac.2020.01.290] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 01/28/2020] [Accepted: 01/29/2020] [Indexed: 01/07/2023]
Abstract
Accumulation of amyloid fibrils in organism accompanies many serious diseases, such as Alzheimer's and Parkinson's diseases, diabetes, prion diseases, etc. It is generally accepted that amyloids are highly resistant to degradation, which complicates their elimination in vivo and is one of the reasons for their pathogenicity. However, using a wide range of physicochemical approaches and specially elaborated method for the tested samples preparation by equilibrium microdialysis technique, it is proved that the stability of amyloids is greatly exaggerated. It turned out that amyloid fibrils formed from at least two amyloidogenic proteins, one of which is a model object for fibrils studying and the second is the cause of hemodialysis amyloidosis in an acute renal failure, are less stable than monomeric proteins. A mechanism of the degradation/reassembly of amyloid fibrils was proposed. It was shown that amyloid «seed» is a factor affecting not only the rate of the fibrils formation, but also their structure. Obtained results are a step towards identifying effects that can lead to degradation of amyloids and their clearance without adverse influence on the functionally active state of the protein or to change the structure and, as a result, the pathogenicity of these protein aggregates.
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Affiliation(s)
- M I Sulatsky
- Institute of Cytology Russian Academy of Science, St. Petersburg, Tikhoretsky ave. 4, 194064, Russia
| | - A I Sulatskaya
- Institute of Cytology Russian Academy of Science, St. Petersburg, Tikhoretsky ave. 4, 194064, Russia
| | - Olga V Stepanenko
- Institute of Cytology Russian Academy of Science, St. Petersburg, Tikhoretsky ave. 4, 194064, Russia
| | - O I Povarova
- Institute of Cytology Russian Academy of Science, St. Petersburg, Tikhoretsky ave. 4, 194064, Russia
| | - I M Kuznetsova
- Institute of Cytology Russian Academy of Science, St. Petersburg, Tikhoretsky ave. 4, 194064, Russia
| | - K K Turoverov
- Institute of Cytology Russian Academy of Science, St. Petersburg, Tikhoretsky ave. 4, 194064, Russia; Peter the Great St.-Petersburg Polytechnic University, St. Petersburg, Polytechnicheskaya 29, 195251, Russia.
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23
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Sulatsky MI, Sulatskaya AI, Povarova OI, Antifeeva IA, Kuznetsova IM, Turoverov KK. Effect of the fluorescent probes ThT and ANS on the mature amyloid fibrils. Prion 2020; 14:67-75. [PMID: 32008441 PMCID: PMC7009331 DOI: 10.1080/19336896.2020.1720487] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Fluorescent probes thioflavin T (ThT) and 1-anilino-8-naphthalene sulfonate (ANS) are widely used to study amyloid fibrils that accumulate in the body of patients with serious diseases, such as Alzheimer’s, Parkinson’s, prion diseases, etc. However, the possible effect of these probes on amyloid fibrils is not well understood. In this work, we investigated the photophysical characteristics, structure, and morphology of mature amyloid fibrils formed from two model proteins, insulin and lysozyme, in the presence of ThT and ANS. It turned out that ANS affects the secondary structure of amyloids (shown for fibrils formed from insulin and lysozyme) and their fibers clusterization (valid for lysozyme fibrils), while ThT has no such effects. These results confirm the differences in the mechanisms of these dyes interaction with amyloid fibrils. Observed effect of ANS was explained by the electrostatic interactions between the dye molecule and cationic groups of amyloid-forming proteins (unlike hydrophobic binding of ThT) that induce amyloids conformational changes. This interaction leads to weakening repulsion between positive charges of amyloid fibrils and can promote their clusterization. It was shown that when fibrillogenesis conditions and, consequently, fibrils structure is changing, as well as during defragmentation of amyloids by ultrasonication, the influence of ANS to amyloids does not change, which indicates the universality of the detected effects. Based on the obtained results, it was concluded that ANS should be used cautiously for the study of amyloid fibrils, since this fluorescence probe have a direct effect on the object of study.
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Affiliation(s)
- M I Sulatsky
- Laboratory of Cell Morphology, Institute of Cytology Russian Academy of Science, St. Petersburg, Russia
| | - A I Sulatskaya
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology Russian Academy of Science, St. Petersburg, Russia
| | - O I Povarova
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology Russian Academy of Science, St. Petersburg, Russia
| | - Iu A Antifeeva
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology Russian Academy of Science, St. Petersburg, Russia
| | - I M Kuznetsova
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology Russian Academy of Science, St. Petersburg, Russia
| | - K K Turoverov
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology Russian Academy of Science, St. Petersburg, Russia.,Institute of Physics, Nanotechnology and Telecommunications, Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russia
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Prajapati KP, Singh AP, Dubey K, Ansari M, Temgire M, Anand BG, Kar K. Myricetin inhibits amyloid fibril formation of globular proteins by stabilizing the native structures. Colloids Surf B Biointerfaces 2020; 186:110640. [DOI: 10.1016/j.colsurfb.2019.110640] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Revised: 09/19/2019] [Accepted: 11/10/2019] [Indexed: 02/06/2023]
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25
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Karmakar S, Chakraborty S, Gautam S, Chowdhury PK. Exploring the potency of the naturally occurring polyphenol curcumin as a probe for protein aggregation in crowded environments. Int J Biol Macromol 2019; 141:1088-1101. [DOI: 10.1016/j.ijbiomac.2019.09.049] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 09/03/2019] [Accepted: 09/06/2019] [Indexed: 01/12/2023]
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26
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Krüger A, Stier A, Fischbach A, Bürkle A, Hauser K, Mangerich A. Interactions of p53 with poly(ADP-ribose) and DNA induce distinct changes in protein structure as revealed by ATR-FTIR spectroscopy. Nucleic Acids Res 2019; 47:4843-4858. [PMID: 30892621 PMCID: PMC6511852 DOI: 10.1093/nar/gkz175] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Revised: 02/22/2019] [Accepted: 03/08/2019] [Indexed: 12/14/2022] Open
Abstract
Due to multiple domains and in part intrinsically disordered regions, structural analyses of p53 remain a challenging task, particularly in complex with DNA and other macromolecules. Here, we applied a novel attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopic approach to investigate changes in secondary structure of full-length p53 induced by non-covalent interactions with DNA and poly(ADP-ribose) (PAR). To validate our approach, we confirmed a positive regulatory function of p53’s C-terminal domain (CTD) with regard to sequence-specific DNA binding and verified that the CTD mediates p53–PAR interaction. Further, we demonstrate that DNA and PAR interactions result in distinct structural changes of p53, indicating specific binding mechanisms via different domains. A time-dependent analysis of the interplay of DNA and PAR binding to p53 revealed that PAR represents p53’s preferred binding partner, which efficiently controls p53–DNA interaction. Moreover, we provide infrared spectroscopic data on PAR pointing to the absence of regular secondary structural elements. Finally, temperature-induced melting experiments via CD spectroscopy show that DNA binding stabilizes the structure of p53, while PAR binding can shift the irreversible formation of insoluble p53 aggregates to higher temperatures. In conclusion, this study provides detailed insights into the dynamic interplay of p53 binding to DNA and PAR at a formerly inaccessible molecular level.
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Affiliation(s)
- Annika Krüger
- Department of Biology, University of Konstanz, Konstanz 78464, Germany.,Department of Chemistry, University of Konstanz, Konstanz 78464, Germany.,Konstanz Research School Chemical Biology, University of Konstanz, Konstanz 78464, Germany.,Zukunftskolleg, University of Konstanz, Konstanz 78464, Germany
| | - Anna Stier
- Department of Biology, University of Konstanz, Konstanz 78464, Germany
| | - Arthur Fischbach
- Department of Biology, University of Konstanz, Konstanz 78464, Germany.,Konstanz Research School Chemical Biology, University of Konstanz, Konstanz 78464, Germany.,Zukunftskolleg, University of Konstanz, Konstanz 78464, Germany
| | - Alexander Bürkle
- Department of Biology, University of Konstanz, Konstanz 78464, Germany
| | - Karin Hauser
- Department of Chemistry, University of Konstanz, Konstanz 78464, Germany
| | - Aswin Mangerich
- Department of Biology, University of Konstanz, Konstanz 78464, Germany
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Cosentino M, Canale C, Bianchini P, Diaspro A. AFM-STED correlative nanoscopy reveals a dark side in fluorescence microscopy imaging. SCIENCE ADVANCES 2019; 5:eaav8062. [PMID: 31223651 PMCID: PMC6584704 DOI: 10.1126/sciadv.aav8062] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 05/13/2019] [Indexed: 05/19/2023]
Abstract
It is known that the presence of fluorophores can influence the dynamics of molecular processes. Despite this, an affordable technique to control the fluorophore distribution within the sample, as well as the rise of unpredictable anomalous processes induced by the fluorophore itself, is missing. We coupled a stimulated emission depletion (STED) microscope with an atomic force microscope to investigate the formation of amyloid aggregates. In particular, we studied the in vitro aggregation of insulin and two alloforms of β amyloid peptides. We followed standard methods to induce the aggregation and to label the molecules at different dye-to-protein ratios. Only a fraction of the fibrillar aggregates was displayed in STED images, indicating that the labeled molecules did not participate indistinctly to the aggregation process. This finding demonstrates that labeled molecules follow only selected pathways of aggregation, among the multiple that are present in the aggregation reaction.
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Affiliation(s)
- Michela Cosentino
- Department of Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy
- DIBRIS Department, University of Genova, Genova, Italy
| | - Claudio Canale
- Department of Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy
- Department of Physics, University of Genova, Genova, Italy
| | - Paolo Bianchini
- Department of Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy
| | - Alberto Diaspro
- Department of Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy
- Department of Physics, University of Genova, Genova, Italy
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28
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Abstract
AbstractThe aggregation of the 11 residue long NACore peptide segment of α-synuclein (68-GAVVTGVTAVA-78) has been investigated using a combination of cryogenic transmission electron microscopy (cryo-TEM), small- and wide-angle X-ray scattering, and spectroscopy techniques. The aqueous peptide solubility is pH dependent, and aggregation was triggered by a pH quench from pH 11.3 to approximately pH 8 or 6, where the average peptide net charge is weakly negative (pH 8), or essentially zero (pH 6). Cryo-TEM shows the presence of long and stiff fibrillar aggregates at both pH, that are built up from β-sheets, as demonstrated by circular dichroism spectroscopy and thioflavin T fluorescence. The fibrils are crystalline, with a wide angle X-ray diffraction pattern that is consistent with a previously determined crystal structure of NACore. Of particular note is the cryo-TEM observation of small globular shaped aggregates, of the order of a few nanometers in size, adsorbed onto the surface of already formed fibrils at pH 6. The fibrillation kinetics is slow, and occurs on the time scale of days. Similarly slow kinetics is observed at both pH, but slightly slower at pH 6, even though the peptide solubility is here expected to be lower. The observation of the small globular shaped aggregates, together with the associated kinetics, could be highly relevant in relation to mechanisms of secondary nucleation and oligomer formation in amyloid systems.
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Saadati-Eskandari N, Navidpour L, Yaghmaei P, Ebrahim-Habibi A. Amino Acids as Additives against Amorphous Aggregation: In Vitro and In Silico Study on Human Lysozyme. Appl Biochem Biotechnol 2019; 189:305-317. [PMID: 30980288 DOI: 10.1007/s12010-019-03010-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 03/27/2019] [Indexed: 01/22/2023]
Abstract
The effect of 16 amino acids (AA) with various physicochemical properties was investigated on human lysozyme (HL) heat-induced amorphous aggregation. UV-Visible spectrophotometry was used to monitor the kinetics of aggregation in the absence and presence of AA, and transmission electron microscopy (TEM) images were taken from the aggregates. To conduct in silico experiments, Autodock vina was used for docking of AA into protein (via YASARA interface), and FTmap information was checked for an insight onto putative binding sites. Prediction of aggregation-prone regions of lysozyme was made by AGGRESCAN and Tango. Among all tested AA, phenylalanine had the best anti-aggregation effect, followed by lysine. In addition, based on in silico tests, Trp 109 and Val 110 of lysozyme are suggested to be of importance in the aggregation process of the enzyme. In conclusion, phenylalanine, arginine, and lysine were found to affect the nucleation phase of lysozyme aggregation and could be considered as suitable stabilizing structures for this enzyme.
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Affiliation(s)
- Naghmeh Saadati-Eskandari
- Department of Biology, Faculty of Basic Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Latifeh Navidpour
- Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, 14174, Iran.
| | - Parichehreh Yaghmaei
- Department of Biology, Faculty of Basic Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Azadeh Ebrahim-Habibi
- Biosensor Research Center, Endocrinology and Metabolism Molecular-Cellular Sciences Institute, Tehran University of Medical Sciences, Jalal-al-Ahmad street, Chamran Highway, Tehran, 1411713137, Iran.
- Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran.
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30
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Hirota N, Edskes H, Hall D. Unified theoretical description of the kinetics of protein aggregation. Biophys Rev 2019; 11:191-208. [PMID: 30888575 DOI: 10.1007/s12551-019-00506-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 02/12/2019] [Indexed: 02/07/2023] Open
Abstract
Solution conditions chosen for the production of amyloid can also promote formation of significant extents of amorphous protein aggregate. In one interpretation, the amyloid and amorphous aggregation pathways are considered to be in competition with each other. An alternative conceptualization involves considering amorphous aggregation as an obligatory intermediate process of the amyloid formation pathway. Here, we review recently developed macroscopic-level theories of protein aggregation that unify these two competing models into a single paradigm. Key features of the unified model included (1) a description of the amorphous aggregate as a second liquid phase with the degree of liquid-like character determined by the mobility of the monomer within it, and (2) heterogeneous growth pathways based on nucleation, growth, and fragmentation of amyloid occurring within different phases and at their interfacial boundary. Limiting-case behaviors of the protein aggregation reaction, either singly involving amyloid or amorphous aggregate production, and mixed-case behaviors, involving competitive and/or facilitated growth of amorphous and amyloid species, are presented and reviewed in context. This review principally describes an approach developed by Hirota and Hall 2019 (Hirota, N. and Hall, D. 2019. Protein Aggregation Kinetics: A Unified Theoretical Description. Chapter 7 of 'Protein Solubility and Amorphous Aggregation: From Academic Research to Applications in Drug Discovery and Bioindustry' edited by Y. Kuroda and F. Arisaka. CMC Publishers). Sections of that work are translated from the original Japanese and republished here with the full permission of CMC Publishing Corporation.
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Affiliation(s)
- Nami Hirota
- Do International Trading House, Koshienguchi-1-chome, Nishinomiya, Hyogo, 6113, Japan
| | - Herman Edskes
- Laboratory of Biochemistry and Genetics, NIDDK, NIH, Bld 8, Bethesda, MD, 20892-0830, USA
| | - Damien Hall
- Institute for Protein Research, Osaka University, 3-1- Yamada-oka, Suita, Osaka, 565-0871, Japan.
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31
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Role of solvent H-bonding and polarity on photophysical properties of a benzothiazole-based ratiometric amyloid fibril sensor. J Photochem Photobiol A Chem 2019. [DOI: 10.1016/j.jphotochem.2018.12.030] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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32
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Stevenson H, Jaggard M, Akhbari P, Vaghela U, Gupte C, Cann P. The role of denatured synovial fluid proteins in the lubrication of artificial joints. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.biotri.2019.03.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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33
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34
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Josefsson L, Cronhamn M, Ekman M, Widehammar H, Emmer Å, Lendel C. Structural basis for the formation of soy protein nanofibrils. RSC Adv 2019; 9:6310-6319. [PMID: 35517292 PMCID: PMC9060953 DOI: 10.1039/c8ra10610j] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 02/15/2019] [Indexed: 11/25/2022] Open
Abstract
Amyloid-like protein nanofibrils (PNFs) can assemble from a range of different proteins including disease-associated proteins, functional amyloid proteins and several proteins for which the PNFs are neither related to disease nor function. We here examined the core building blocks of PNFs formed by soy proteins. Fibril formation at pH 2 and 90 °C is coupled to peptide hydrolysis which allows isolation of the PNF-forming peptides and identification of them by mass spectrometry. We found five peptides that constitute the main building blocks in soy PNFs, three of them from the protein β-conglycinin and two from the protein glycinin. The abilities of these peptides to form PNFs were addressed by amyloid prediction software and by PNF formation of the corresponding synthetic peptides. Analysis of the structural context in the native soy proteins revealed two structural motifs for the PNF-forming peptides: (i) so-called β-arches and (ii) helical segments involved in quaternary structure contacts. However, the results suggest that neither the native structural motifs nor the protein of origin defines the morphology of the PNFs formed from soy protein isolate. Identification of the peptide building blocks of soy protein nanofibrils provides new clues about the determinants of protein nanofibril morphology.![]()
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Affiliation(s)
- Leila Josefsson
- Department of Chemistry
- KTH Royal Institute of Technology
- Stockholm
- Sweden
| | - Melker Cronhamn
- Department of Chemistry
- KTH Royal Institute of Technology
- Stockholm
- Sweden
| | - Malin Ekman
- Department of Chemistry
- KTH Royal Institute of Technology
- Stockholm
- Sweden
| | - Hugo Widehammar
- Department of Chemistry
- KTH Royal Institute of Technology
- Stockholm
- Sweden
| | - Åsa Emmer
- Department of Chemistry
- KTH Royal Institute of Technology
- Stockholm
- Sweden
| | - Christofer Lendel
- Department of Chemistry
- KTH Royal Institute of Technology
- Stockholm
- Sweden
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35
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Dao HM, Chen J, Tucker BS, Thomas V, Jun HW, Li XC, Jo S. Hemopressin-Based pH-Sensitive Hydrogel: A Potential Bioactive Platform for Drug Delivery. ACS Biomater Sci Eng 2018; 4:2435-2442. [DOI: 10.1021/acsbiomaterials.8b00423] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Huy Minh Dao
- Department of Pharmaceutics and Drug Delivery, University of Mississippi, Oxford, Mississippi 38677, United States
| | - Jun Chen
- Department of Biomedical Engineering, University of Alabama at Birmingham, Birmingham, Alabama 35294, United States
| | - Bernabe S. Tucker
- Department of Materials Science and Engineering, University of Alabama at Birmingham, Birmingham, Alabama 35294, United States
| | - Vinoy Thomas
- Department of Materials Science and Engineering, University of Alabama at Birmingham, Birmingham, Alabama 35294, United States
| | - Ho-Wook Jun
- Department of Biomedical Engineering, University of Alabama at Birmingham, Birmingham, Alabama 35294, United States
| | - Xing-Cong Li
- National Center for Natural Products Research, University of Mississippi, Oxford, Mississippi 38677, United States
| | - Seongbong Jo
- Department of Pharmaceutics and Drug Delivery, University of Mississippi, Oxford, Mississippi 38677, United States
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Amyloid fibrillation of an intrinsically disordered plant phloem protein AtPP16-1 under acidic condition. Biophys Chem 2018; 237:1-8. [PMID: 29605501 DOI: 10.1016/j.bpc.2018.03.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 03/22/2018] [Accepted: 03/22/2018] [Indexed: 12/25/2022]
Abstract
Arabidopsis thaliana Phloem Protein 16-1 (AtPP16-1) is a 156-residue intrinsically disordered nucleic acid binding protein which is putatively involved in long-distance systemic transport of RNA to budding regions in plants. Dimerization or oligomerization of the protein at pH higher than about 4.1 leaves no apolar surface exposed for interaction with the dye 8-Anilinonaphthalene-1-sulfonate (ANS). The most stable monomeric state is found near pH 4 where the structure of the protein is determined to have three short β-strands and a single α-helix. By surveying the pH-dependent propensity of fibrillation we find the protein enters the amyloidogenic state at pH 2, 60 °C. The reaction product is not amorphous aggregate, but simple amyloid fibrils with sparse or no branching. The mean diameters of the fibril population scaled from AFM images are 13.2 and 21.2 nm for precursor aggregates (PA) and proto- or elongated fibrils, respectively. These values are somewhat larger than the fibril diameters generally cited, and the reason could be larger lateral association for both PA and protofibrils. The protein AtPP16-1 is strictly pH-selective in terms of its structure and stability, and the solution structure is known at pH 4. Under the conditions of pH 2 used here for fibrillation, the protein retains substantial secondary structure. Even if the pH and temperature conditions used for fibrillation are hardly physiological, there is a finite possibility that some aggregation of AtPP16-1 would occur in vivo, as the case of transglutaminase aggregates in the chloroplast of transplastomic plants, for example. The pH related problem has been discussed in detail, but the questions emanating are: do phloem proteins fibrillate in vivo, and if so what implication fibrillation has for plant physiology?
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Oshinbolu S, Shah R, Finka G, Molloy M, Uden M, Bracewell DG. Evaluation of fluorescent dyes to measure protein aggregation within mammalian cell culture supernatants. JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY (OXFORD, OXFORDSHIRE : 1986) 2018; 93:909-917. [PMID: 29540956 PMCID: PMC5838538 DOI: 10.1002/jctb.5519] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 11/15/2017] [Accepted: 11/15/2017] [Indexed: 06/28/2023]
Abstract
BACKGROUND A current challenge in bioprocessing is the ability to analyse critical quality attributes such as aggregation without prior purification. This study evaluated the use of fluorescent dyes (Bis-ANS, SYPRO Orange, Thioflavin T and ProteoStat) to characterise mAb aggregates in Chinese hamster ovary clarified cultures. RESULTS The null and mAb culture supernatants showed an increase in fluorescence intensity over the duration of the culture. The null cultures on day 14 saw a rapid increase in fluorescence intensity; day 10 to day 14, Bis-ANS and Thioflavin T had average increases of 21% and 48%, respectively, whereas ProteoStat and SYPRO Orange showed an average increase of 60%. Higher fluorescence intensity on day 14 with the null cultures, also correlated with loss of viability. CONCLUSION Fluorescent dyes are not a specific indicator of mAb aggregation, but rather an indicator of overall protein aggregation or high molecular weight species. SYPRO Orange was more sensitive at detecting very large molecular weight species and ProteoStat seemed better suited to smaller aggregates. Although the assay cannot be used to measure mAb aggregates in cell culture, it could be used to aid cell line selection in maximising viabilities and minimising the amount of aggregates. © 2017 The Authors. Journal of Chemical Technology & Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Sheun Oshinbolu
- Dept of Biochemical EngineeringUniversity College LondonLondonUK
- GlaxoSmithKlineStevenageHertsUK
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38
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A mechanistic insight into protein-ligand interaction, folding, misfolding, aggregation and inhibition of protein aggregates: An overview. Int J Biol Macromol 2018; 106:1115-1129. [DOI: 10.1016/j.ijbiomac.2017.07.185] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Revised: 07/28/2017] [Accepted: 07/30/2017] [Indexed: 11/22/2022]
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Gaglione R, Smaldone G, Di Girolamo R, Piccoli R, Pedone E, Arciello A. Cell milieu significantly affects the fate of AApoAI amyloidogenic variants: predestination or serendipity? Biochim Biophys Acta Gen Subj 2017; 1862:377-384. [PMID: 29174954 DOI: 10.1016/j.bbagen.2017.11.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 11/17/2017] [Accepted: 11/21/2017] [Indexed: 12/12/2022]
Abstract
BACKGROUND Specific apolipoprotein A-I variants are associated to severe hereditary amyloidoses. The organ distribution of AApoAI amyloidosis seems to depend on the position of the mutation, since mutations in residues from 1 to 75 are mainly associated to hepatic and renal amyloidosis, while mutations in residues from 173 to 178 are mostly responsible for cardiac, laryngeal, and cutaneous amyloidosis. Molecular bases of this tissue specificity are still poorly understood, but it is increasingly emerging that protein destabilization induced by amyloidogenic mutations is neither necessary nor sufficient for amyloidosis development. METHODS By using a multidisciplinary approach, including circular dichroism, dynamic light scattering, spectrofluorometric and atomic force microscopy analyses, the effect of target cells on the conformation and fibrillogenic pathway of the two AApoAI amyloidogenic variants AApoAIL75P and AApoAIL174S has been monitored. RESULTS Our data show that specific cell milieus selectively affect conformation, aggregation propensity and fibrillogenesis of the two AApoAI amyloidogenic variants. CONCLUSIONS An intriguing picture emerged indicating that defined cell contexts selectively induce fibrillogenesis of specific AApoAI variants. GENERAL SIGNIFICANCE An innovative methodological approach, based on the use of whole intact cells to monitor the effects of cell context on AApoAI variants fibrillogenic pathway, has been set up.
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Affiliation(s)
- Rosa Gaglione
- Department of Chemical Sciences, University of Naples Federico II, 80126 Naples, Italy
| | | | - Rocco Di Girolamo
- Department of Chemical Sciences, University of Naples Federico II, 80126 Naples, Italy
| | - Renata Piccoli
- Department of Chemical Sciences, University of Naples Federico II, 80126 Naples, Italy; Istituto Nazionale di Biostrutture e Biosistemi (INBB), Italy
| | - Emilia Pedone
- Istituto di Biostrutture e Bioimmagini, CNR, Naples, Italy; Research Centre on Bioactive Peptides (CIRPeB), University of Naples Federico II, Via Mezzocannone 16, 80134 Naples, Italy.
| | - Angela Arciello
- Department of Chemical Sciences, University of Naples Federico II, 80126 Naples, Italy; Istituto Nazionale di Biostrutture e Biosistemi (INBB), Italy.
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40
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Chaotropes trigger conformational rearrangements differently in Concanavalin A. J CHEM SCI 2017. [DOI: 10.1007/s12039-017-1333-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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41
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Khan MV, Ishtikhar M, Siddiqui MK, Zaman M, Chandel TI, Majid N, Ajmal MR, Abdelhameed AS, Shahein YE, Khan RH. Biophysical insight reveals tannic acid as amyloid inducer and conformation transformer from amorphous to amyloid aggregates in Concanavalin A (ConA). J Biomol Struct Dyn 2017; 36:1261-1273. [DOI: 10.1080/07391102.2017.1318718] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Mohsin Vahid Khan
- Molecular Biophysics and Biophysical Chemistry Group, Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh 202002, India
| | - Mohd. Ishtikhar
- Molecular Biophysics and Biophysical Chemistry Group, Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh 202002, India
| | - Mohammad Khursheed Siddiqui
- Molecular Biophysics and Biophysical Chemistry Group, Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh 202002, India
| | - Masihuz Zaman
- Molecular Biophysics and Biophysical Chemistry Group, Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh 202002, India
| | - Tajalli Ilm Chandel
- Molecular Biophysics and Biophysical Chemistry Group, Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh 202002, India
| | - Nabeela Majid
- Molecular Biophysics and Biophysical Chemistry Group, Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh 202002, India
| | - Mohd. Rehan Ajmal
- Molecular Biophysics and Biophysical Chemistry Group, Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh 202002, India
| | - Ali Saber Abdelhameed
- Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia
| | - Yasser E. Shahein
- Molecular Biology Department, Genetic Engineering and Biotechnology Division, National Research Centre, Dokki, Cairo, Egypt
| | - Rizwan Hasan Khan
- Molecular Biophysics and Biophysical Chemistry Group, Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh 202002, India
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Lavanya V, Anil Kumar B, Jamal S, Khan MKA, Ahmed N. Sub-Micellar Concentration of Sodium Dodecyl Sulphate Prevents Thermal Denaturation Induced Aggregation of Plant Lectin, Jacalin. Protein J 2017; 36:17-27. [PMID: 28133706 DOI: 10.1007/s10930-017-9694-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The irreversible thermal unfolding of jacalin, the lectin purified from jackfruit seeds was accompanied by aggregation, where intermolecular interactions among the subunits are favoured over intramolecular interactions. The extent of aggregation increased as a function of temperature, time and protein concentration. The anionic surfactant, sodium dodecyl sulphate (SDS) significantly suppressed the formation of aggregates as observed by turbidity measurements and Rayleigh scattering assay. Moreover, far UV-CD spectra indicate that the protein β sheet transforms into α helical structure, when denatured in the presence of 3 mM SDS. Further, jacalin when heated in the presence of SDS partially retained the hemagglutination activity when jacalin-SDS mixture was diluted to 1:8 factor since 3 mM SDS was found to lyse the red blood cells. Thus, SDS only altered the aggregation behaviour of jacalin by preventing intermolecular hydrogen bonding among the exposed residues but did not completely stabilize the native conformation.
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Affiliation(s)
- V Lavanya
- School of Life Sciences, B S Abdur Rahman University, GST Road, Vandalur, Chennai, Tamil Nadu, 600048, India
| | - B Anil Kumar
- School of Life Sciences, B S Abdur Rahman University, GST Road, Vandalur, Chennai, Tamil Nadu, 600048, India
| | - Shazia Jamal
- School of Life Sciences, B S Abdur Rahman University, GST Road, Vandalur, Chennai, Tamil Nadu, 600048, India
| | - Md Khurshid Alam Khan
- School of Life Sciences, B S Abdur Rahman University, GST Road, Vandalur, Chennai, Tamil Nadu, 600048, India
| | - Neesar Ahmed
- School of Life Sciences, B S Abdur Rahman University, GST Road, Vandalur, Chennai, Tamil Nadu, 600048, India.
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43
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Ahmed A, Shamsi A, Bano B. Characterizing harmful advanced glycation end-products (AGEs) and ribosylated aggregates of yellow mustard seed phytocystatin: Effects of different monosaccharides. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2017; 171:183-192. [PMID: 27526342 DOI: 10.1016/j.saa.2016.08.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 07/20/2016] [Accepted: 08/04/2016] [Indexed: 06/06/2023]
Abstract
Advanced glycation end products (AGEs) are at the core of variety of diseases ranging from diabetes to renal failure and hence gaining wide consideration. This study was aimed at characterizing the AGEs of phytocystatin isolated from mustard seeds (YMP) when incubated with different monosaccharides (glucose, ribose and mannose) using fluorescence, ultraviolet, circular dichroism (CD) spectroscopy and microscopy. Ribose was found to be the most potent glycating agent as evident by AGEs specific fluorescence and absorbance. YMP exists as a molten globule like structure on day 24 as depicted by high ANS fluorescence and altered intrinsic fluorescence. Glycated YMP as AGEs and ribose induced aggregates were observed at day 28 and 32 respectively. In our study we have also examined the anti-aggregative potential of polyphenol, resveratrol. Our results suggested the anti-aggregative behavior of resveratrol as it prevented the in vitro aggregation of YMP, although further studies are required to decode the mechanism by which resveratrol prevents the aggregation.
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Affiliation(s)
- Azaj Ahmed
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, India
| | - Anas Shamsi
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, India
| | - Bilqees Bano
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, India.
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44
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Ma H, DaSilva NA, Liu W, Nahar PP, Wei Z, Liu Y, Pham PT, Crews R, Vattem DA, Slitt AL, Shaikh ZA, Seeram NP. Effects of a Standardized Phenolic-Enriched Maple Syrup Extract on β-Amyloid Aggregation, Neuroinflammation in Microglial and Neuronal Cells, and β-Amyloid Induced Neurotoxicity in Caenorhabditis elegans. Neurochem Res 2016; 41:2836-2847. [PMID: 27418278 PMCID: PMC5819752 DOI: 10.1007/s11064-016-1998-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 06/27/2016] [Accepted: 06/30/2016] [Indexed: 11/28/2022]
Abstract
Published data supports the neuroprotective effects of several phenolic-containing natural products, including certain fruit, berries, spices, nuts, green tea, and olive oil. However, limited data are available for phenolic-containing plant-derived natural sweeteners including maple syrup. Herein, we investigated the neuroprotective effects of a chemically standardized phenolic-enriched maple syrup extract (MSX) using a combination of biophysical, in vitro, and in vivo studies. Based on biophysical data (Thioflavin T assay, transmission electron microscopy, circular dichroism, dynamic light scattering, and zeta potential), MSX reduced amyloid β1-42 peptide (Aβ1-42) fibrillation in a concentration-dependent manner (50-500 μg/mL) with similar effects as the neuroprotective polyphenol, resveratrol, at its highest test concentration (63.5 % at 500 μg/mL vs. 77.3 % at 50 μg/mL, respectively). MSX (100 μg/mL) decreased H2O2-induced oxidative stress (16.1 % decrease in ROS levels compared to control), and down-regulated the production of lipopolysaccharide (LPS)-stimulated inflammatory markers (22.1, 19.9, 74.8, and 87.6 % decrease in NOS, IL-6, PGE2, and TNFα levels, respectively, compared to control) in murine BV-2 microglial cells. Moreover, in a non-contact co-culture cell model, differentiated human SH-SY5Y neuronal cells were exposed to conditioned media from BV-2 cells treated with MSX (100 μg/mL) and LPS or LPS alone. MSX-BV-2 media increased SH-SY5Y cell viability by 13.8 % compared to media collected from LPS-BV-2 treated cells. Also, MSX (10 μg/mL) showed protective effects against Aβ1-42 induced neurotoxicity and paralysis in Caenorhabditis elegans in vivo. These data support the potential neuroprotective effects of MSX warranting further studies on this natural product.
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Affiliation(s)
- Hang Ma
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI, 02881, USA
| | - Nicholas A DaSilva
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI, 02881, USA
| | - Weixi Liu
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI, 02881, USA
| | - Pragati P Nahar
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI, 02881, USA
| | - Zhengxi Wei
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI, 02881, USA
| | - Yongqiang Liu
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI, 02881, USA
| | - Priscilla T Pham
- Nutrition Biomedicine and Biotechnology, Texas State University, San Marcos, TX, 78666, USA
| | - Rebecca Crews
- Nutrition Biomedicine and Biotechnology, Texas State University, San Marcos, TX, 78666, USA
| | - Dhiraj A Vattem
- Nutrition Biomedicine and Biotechnology, Texas State University, San Marcos, TX, 78666, USA
- School of Applied Health Sciences and Wellness, Grover Center E160A, Ohio University, Athens, OH, 45701, USA
| | - Angela L Slitt
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI, 02881, USA
| | - Zahir A Shaikh
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI, 02881, USA
| | - Navindra P Seeram
- Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI, 02881, USA.
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45
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Ranganathan S, Maji SK, Padinhateeri R. Defining a Physical Basis for Diversity in Protein Self-Assemblies Using a Minimal Model. J Am Chem Soc 2016; 138:13911-13922. [DOI: 10.1021/jacs.6b06433] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Srivastav Ranganathan
- Department of Biosciences
and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Samir K. Maji
- Department of Biosciences
and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Ranjith Padinhateeri
- Department of Biosciences
and Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
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46
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Khan MV, Ishtikhar M, Rabbani G, Zaman M, Abdelhameed AS, Khan RH. Polyols (Glycerol and Ethylene glycol) mediated amorphous aggregate inhibition and secondary structure restoration of metalloproteinase-conalbumin (ovotransferrin). Int J Biol Macromol 2016; 94:290-300. [PMID: 27744055 PMCID: PMC7112414 DOI: 10.1016/j.ijbiomac.2016.10.023] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 10/10/2016] [Indexed: 11/24/2022]
Abstract
Conalbumin aggregates at 65 °C and denaturation occur at above this temperature. The nature of aggregates was identified as amorphous. The polyols inhibits the aggregation of conalbumin via protecting the secondary structure. Glycerol is found to be more protective than ethylene glycol.
Under physical or chemical stress, proteins tend to form aggregates either highly ordered (amyloid) or unordered (amorphous) causing many pathological disorders in human and loss of proteins functionality in both laboratory conditions and industries during production and storage at commercial level. We investigated the effect of increasing temperature on Conalbumin (CA) and induced aggregation at 65 °C. The enhanced Thioflavin T (ThT) and ANS (1-anilinonaphtalene 8-sulfonic acid) fluorescence intensity, show no shift on Congo red binding, additionally, transmission and scanning electron microscopy (TEM) (SEM) reveal amorphous morphology of the aggregate. Our investigation clearly demonstrated that polyols namely Glycerol (GL) and Ethylene glycol (EG) are so staunch to inhibit amorphous aggregates via restoring secondary conformation. Addition of polyols (15% GL and 35% EG) significantly decrease the turbidity, Rayleigh scattering ThT and ANS fluorescence intensity. The dynamic light scattering (DLS) data show that hydrodynamic radii (Rh) of the aggregates is ∼20 times higher than native CA while nearly similar for GL and EG protected CA due to condensation of core size with little difference.
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Affiliation(s)
- Mohsin Vahid Khan
- Molecular Biophysics and Biophysical Chemistry Group, Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, 202002, India
| | - Mohd Ishtikhar
- Molecular Biophysics and Biophysical Chemistry Group, Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, 202002, India
| | - Gulam Rabbani
- Molecular Biophysics and Biophysical Chemistry Group, Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, 202002, India
| | - Masihuz Zaman
- Molecular Biophysics and Biophysical Chemistry Group, Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, 202002, India
| | - Ali Saber Abdelhameed
- Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Rizwan Hasan Khan
- Molecular Biophysics and Biophysical Chemistry Group, Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, 202002, India.
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Nokwe CN, Hora M, Zacharias M, Yagi H, Peschek J, Reif B, Goto Y, Buchner J. A Stable Mutant Predisposes Antibody Domains to Amyloid Formation through Specific Non-Native Interactions. J Mol Biol 2016; 428:1315-1332. [DOI: 10.1016/j.jmb.2016.01.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 01/10/2016] [Accepted: 01/15/2016] [Indexed: 12/17/2022]
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48
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Carcamo-Noriega EN, Saab-Rincon G. Identification of fibrillogenic regions in human triosephosphate isomerase. PeerJ 2016; 4:e1676. [PMID: 26870617 PMCID: PMC4748702 DOI: 10.7717/peerj.1676] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2015] [Accepted: 01/20/2016] [Indexed: 12/31/2022] Open
Abstract
Background. Amyloid secondary structure relies on the intermolecular assembly of polypeptide chains through main-chain interaction. According to this, all proteins have the potential to form amyloid structure, nevertheless, in nature only few proteins aggregate into toxic or functional amyloids. Structural characteristics differ greatly among amyloid proteins reported, so it has been difficult to link the fibrillogenic propensity with structural topology. However, there are ubiquitous topologies not represented in the amyloidome that could be considered as amyloid-resistant attributable to structural features, such is the case of TIM barrel topology. Methods. This work was aimed to study the fibrillogenic propensity of human triosephosphate isomerase (HsTPI) as a model of TIM barrels. In order to do so, aggregation of HsTPI was evaluated under native-like and destabilizing conditions. Fibrillogenic regions were identified by bioinformatics approaches, protein fragmentation and peptide aggregation. Results. We identified four fibrillogenic regions in the HsTPI corresponding to the β3, β6, β7 y α8 of the TIM barrel. From these, the β3-strand region (residues 59–66) was highly fibrillogenic. In aggregation assays, HsTPI under native-like conditions led to amorphous assemblies while under partially denaturing conditions (urea 3.2 M) formed more structured aggregates. This slightly structured aggregates exhibited residual cross-β structure, as demonstrated by the recognition of the WO1 antibody and ATR-FTIR analysis. Discussion. Despite the fibrillogenic regions present in HsTPI, the enzyme maintained under native-favoring conditions displayed low fibrillogenic propensity. This amyloid-resistance can be attributed to the three-dimensional arrangement of the protein, where β-strands, susceptible to aggregation, are protected in the core of the molecule. Destabilization of the protein structure may expose inner regions promoting β-aggregation, as well as the formation of hydrophobic disordered aggregates. Being this last pathway kinetically favored over the thermodynamically more stable fibril aggregation pathway.
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Affiliation(s)
- Edson N Carcamo-Noriega
- Instituto de Biotecnología, Departamento de Ingeniería Celular y Biocatálisis, Universidad Nacional Autónoma de México , Cuernavaca, Morelos , Mexico
| | - Gloria Saab-Rincon
- Instituto de Biotecnología, Departamento de Ingeniería Celular y Biocatálisis, Universidad Nacional Autónoma de México , Cuernavaca, Morelos , Mexico
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49
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Santangelo MG, Foderà V, Militello V, Vetri V. Back to the oligomeric state: pH-induced dissolution of concanavalin A amyloid-like fibrils into non-native oligomers. RSC Adv 2016. [DOI: 10.1039/c6ra16690c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Changes in solution pH may result in modifications of energy landscape shape making readily accessible or more favourable native or oligomeric intermediate minima with respect to the fibrillar one.
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Affiliation(s)
- M. G. Santangelo
- Department of Physics and Chemistry
- University of Palermo
- Palermo
- Italy
| | - V. Foderà
- Section for Biologics
- Department of Pharmacy
- Faculty of Health and Medical Sciences
- University of Copenhagen
- Copenhagen
| | - V. Militello
- Department of Physics and Chemistry
- University of Palermo
- Palermo
- Italy
| | - V. Vetri
- Department of Physics and Chemistry
- University of Palermo
- Palermo
- Italy
- Aten Center
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50
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Ishtikhar M, Ali MS, Atta AM, Al-Lohedan H, Badr G, Khan RH. Temperature dependent rapid annealing effect induces amorphous aggregation of human serum albumin. Int J Biol Macromol 2016; 82:844-55. [DOI: 10.1016/j.ijbiomac.2015.10.071] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 10/21/2015] [Indexed: 10/22/2022]
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