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Protein Microgels from Amyloid Fibril Networks. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1174:223-263. [PMID: 31713201 DOI: 10.1007/978-981-13-9791-2_7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Nanofibrillar forms of amyloidogenic proteins were initially discovered in the context of protein misfolding and disease but have more recently been found at the origin of key biological functionality in many naturally occurring functional materials, such as adhesives and biofilm coatings. Their physiological roles in nature reflect their great strength and stability, which has led to the exploration of their use as the basis of artificial protein-based functional materials. Particularly for biomedical applications, they represent attractive building blocks for the development of, for instance, drug carrier agents due to their inherent biocompatibility and biodegradability. Furthermore, the propensity of proteins to self-assemble into amyloid fibrils can be exploited under microconfinement, afforded by droplet microfluidic techniques. This approach allows the generation of multi-scale functional microgels that can host biological additives and can be designed to incorporate additional functionality, such as to aid targeted drug delivery.
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Parkinson's disease is a type of amyloidosis featuring accumulation of amyloid fibrils of α-synuclein. Proc Natl Acad Sci U S A 2019; 116:17963-17969. [PMID: 31427526 PMCID: PMC6731630 DOI: 10.1073/pnas.1906124116] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Lewy bodies (LBs), which mainly consist of α-syn, are neuropathological hallmarks of patients with Parkinson’s disease (PD). Recently, it has been reported that aggregates of α-syn with cross-β structures are capable of propagating within the brain in a prionlike manner. However, there is still no evidence that such propagation occurs in the patient’s brain. Here, we examined LBs in thin sections of autopsy brains of patients with PD using microbeam X-ray diffraction (XRD) and confirmed that aggregates of α-syn with a cross-β structure exist in brains of PD patients. Our finding supports the concept that PD is a type of amyloidosis, a disease featuring the accumulation and propagation of amyloid fibrils of α-syn. Many neurodegenerative diseases are characterized by the accumulation of abnormal protein aggregates in the brain. In Parkinson’s disease (PD), α-synuclein (α-syn) forms such aggregates called Lewy bodies (LBs). Recently, it has been reported that aggregates of α-syn with a cross-β structure are capable of propagating within the brain in a prionlike manner. However, the presence of cross-β sheet-rich aggregates in LBs has not been experimentally demonstrated so far. Here, we examined LBs in thin sections of autopsy brains of patients with PD using microbeam X-ray diffraction (XRD) and found that some of them gave a diffraction pattern typical of a cross-β structure. This result confirms that LBs in the brain of PD patients contain amyloid fibrils with a cross-β structure and supports the validity of in vitro propagation experiments using artificially formed amyloid fibrils of α-syn. Notably, our finding supports the concept that PD is a type of amyloidosis, a disease featuring the accumulation of amyloid fibrils of α-syn.
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Haymond A, Dey D, Carter R, Dailing A, Nara V, Nara P, Venkatayogi S, Paige M, Liotta L, Luchini A. Protein painting, an optimized MS-based technique, reveals functionally relevant interfaces of the PD-1/PD-L1 complex and the YAP2/ZO-1 complex. J Biol Chem 2019; 294:11180-11198. [PMID: 31167787 DOI: 10.1074/jbc.ra118.007310] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 05/31/2019] [Indexed: 12/26/2022] Open
Abstract
Protein-protein interactions lie at the heart of many biological processes and therefore represent promising drug targets. Despite this opportunity, identification of protein-protein interfaces remains challenging. We have previously developed a method that relies on coating protein surfaces with small-molecule dyes to discriminate between solvent-accessible protein surfaces and hidden interface regions. Dye-bound, solvent-accessible protein regions resist trypsin digestion, whereas hidden interface regions are revealed by denaturation and sequenced by MS. The small-molecule dyes bind promiscuously and with high affinity, but their binding mechanism is unknown. Here, we report on the optimization of a novel dye probe used in protein painting, Fast Blue B + naphthionic acid, and show that its affinity for proteins strongly depends on hydrophobic moieties that we call here "hydrophobic clamps." We demonstrate the utility of this probe by sequencing the protein-protein interaction regions between the Hippo pathway protein Yes-associated protein 2 (YAP2) and tight junction protein 1 (TJP1 or ZO-1), uncovering interactions via the known binding domain as well as ZO-1's MAGUK domain and YAP's N-terminal proline-rich domain. Additionally, we demonstrate how residues predicted by protein painting are present exclusively in the complex interface and how these residues may guide the development of peptide inhibitors using a case study of programmed cell death protein 1 (PD-1) and programmed cell death 1 ligand 1 (PD-L1). Inhibitors designed around the PD-1/PD-L1 interface regions identified via protein painting effectively disrupted complex formation, with the most potent inhibitor having an IC50 of 5 μm.
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Affiliation(s)
- Amanda Haymond
- Center for Applied Proteomics and Molecular Medicine, George Mason University, Manassas, Virginia 20110
| | - Douglass Dey
- Center for Applied Proteomics and Molecular Medicine, George Mason University, Manassas, Virginia 20110
| | - Rachel Carter
- Center for Applied Proteomics and Molecular Medicine, George Mason University, Manassas, Virginia 20110
| | - Angela Dailing
- Center for Applied Proteomics and Molecular Medicine, George Mason University, Manassas, Virginia 20110
| | - Vaishnavi Nara
- Thomas Jefferson High School for Science and Technology, Alexandria, Virginia 22312
| | - Pranavi Nara
- University of Pittsburgh, Pittsburgh, Pennsylvania 15260
| | - Sravani Venkatayogi
- Center for Applied Proteomics and Molecular Medicine, George Mason University, Manassas, Virginia 20110
| | - Mikell Paige
- Department of Chemistry and Biochemistry, George Mason University, Fairfax, Virginia 20110
| | - Lance Liotta
- Center for Applied Proteomics and Molecular Medicine, George Mason University, Manassas, Virginia 20110
| | - Alessandra Luchini
- Center for Applied Proteomics and Molecular Medicine, George Mason University, Manassas, Virginia 20110
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Anand BG, Prajapati KP, Dubey K, Ahamad N, Shekhawat DS, Rath PC, Joseph GK, Kar K. Self-Assembly of Artificial Sweetener Aspartame Yields Amyloid-like Cytotoxic Nanostructures. ACS NANO 2019; 13:6033-6049. [PMID: 31021591 DOI: 10.1021/acsnano.9b02284] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Recent reports have revealed the intrinsic propensity of single aromatic metabolites to undergo self-assembly and form nanostructures of amyloid nature. Hence, identifying whether aspartame, a universally consumed artificial sweetener, is inherently aggregation prone becomes an important area of investigation. Although the reports on aspartame-linked side effects describe a multitude of metabolic disorders, the mechanistic understanding of such destructive effects is largely mysterious. Since aromaticity, an aggregation-promoting factor, is intrinsic to aspartame's chemistry, it is important to know whether aspartame can undergo self-association and if such a property can predispose any cytotoxicity to biological systems. Our study finds that aspartame molecules, under mimicked physiological conditions, undergo a spontaneous self-assembly process yielding regular β-sheet-like cytotoxic nanofibrils of amyloid nature. The resultant aspartame fibrils were found to trigger amyloid cross-seeding and become a toxic aggregation trap for globular proteins, Aβ peptides, and aromatic metabolites that convert native structures to β-sheet-like fibrils. Aspartame fibrils were also found to induce hemolysis, causing DNA damage resulting in both apoptosis and necrosis-mediated cell death. Specific spatial arrangement between aspartame molecules is predicted to form a regular amyloid-like architecture with a sticky exterior that is capable of promoting viable H-bonds, electrostatic interactions, and hydrophobic contacts with biomolecules, leading to the onset of protein aggregation and cell death. Results reveal that the aspartame molecule is inherently amyloidogenic, and the self-assembly of aspartame becomes a toxic trap for proteins and cells, exposing the bitter side of such a ubiquitously used artificial sweetener.
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Affiliation(s)
- Bibin Gnanadhason Anand
- Department of Bioscience and Bioengineering , Indian Institute of Technology Jodhpur , Jodhpur 342037 , India
| | | | - Kriti Dubey
- School of Life Sciences , Jawaharlal Nehru University , New Delhi 110067 , India
| | - Naseem Ahamad
- School of Life Sciences , Jawaharlal Nehru University , New Delhi 110067 , India
| | - Dolat Singh Shekhawat
- Department of Bioscience and Bioengineering , Indian Institute of Technology Jodhpur , Jodhpur 342037 , India
| | - Pramod Chandra Rath
- School of Life Sciences , Jawaharlal Nehru University , New Delhi 110067 , India
| | - George Kodimattam Joseph
- Department of Bioscience and Bioengineering , Indian Institute of Technology Jodhpur , Jodhpur 342037 , India
| | - Karunakar Kar
- School of Life Sciences , Jawaharlal Nehru University , New Delhi 110067 , India
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55
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Sudhakar S, Mani E. Rapid Dissolution of Amyloid β Fibrils by Silver Nanoplates. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:6962-6970. [PMID: 31030521 DOI: 10.1021/acs.langmuir.9b00080] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Plaques of amyloid beta (Aβ) protein are associated with neurodegenerative diseases, and preventing their formation and dissolution of plaques are essential to the development of therapeutics. In this study, silver triangular nanoplates (AgTNPs) are shown to dissolve mature Aβ fibrils because of their plasmonic photothermal property. Mature Aβ fibrils treated with AgTNPs under near-infrared (NIR)-illuminated conditions are dissolved in less than 1 h, while an equal concentration of silver spherical nanoparticles took about 70 h. The concentration of the fibrils decreased from 10 to 0.3 μM upon treating the amyloid fibrils with AgTNPs under NIR. AgTNPs are also shown to prevent the formation of Aβ fibrils by selective binding to the positively charged amyloidogenic sequence of the Aβ monomer. The kinetics of inhibition by AgTNPs follows the predictions of the detailed kinetic model (Ramesh et al., Langmuir 2018, 34, 4004-4012). The kinetics of dissolution and inhibition are characterized by Congo red/ThT assay, transmission electronic microscopy, atomic force microscopy, and attenuated total reflectance Fourier transform-infrared spectroscopy. Cell viability studies on SH-SY5Y and BE-(2)-C cells using 3-[4,5-dimethy-lthi-azol-2-yl]-2,5-diphenyl-tetrazdium bromide and lactate dehydrogenase assay show that the viability of the cells increased from 33 to 70% on treating the cells with AgTNP-incubated Aβ fibrils compared to the mature Aβ fibrils. The study provides new insights to design plasmonic nanoparticle-based therapeutics to cure neurodegenerative diseases.
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Affiliation(s)
- Swathi Sudhakar
- Polymer Engineering and Colloid Science Laboratory, Department of Chemical Engineering , Indian Institute of Technology, Madras , Chennai 600 036 , India
| | - Ethayaraja Mani
- Polymer Engineering and Colloid Science Laboratory, Department of Chemical Engineering , Indian Institute of Technology, Madras , Chennai 600 036 , India
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56
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Congo Red and amyloids: history and relationship. Biosci Rep 2019; 39:BSR20181415. [PMID: 30567726 PMCID: PMC6331669 DOI: 10.1042/bsr20181415] [Citation(s) in RCA: 179] [Impact Index Per Article: 35.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 12/16/2018] [Accepted: 12/17/2018] [Indexed: 12/17/2022] Open
Abstract
Staining with Congo Red (CR) is a qualitative method used for the identification of amyloids in vitro and in tissue sections. However, the drawbacks and artefacts obtained when using this dye can be found both in vitro and in vivo. Analysis of scientific data from previous studies shows that CR staining alone is not sufficient for confirmation of the amyloid nature of protein aggregates in vitro or for diagnosis of amyloidosis in tissue sections. In the present paper, we describe the characteristics and limitations of other methods used for amyloid studies. Our historical review on the use of CR staining for amyloid studies may provide insight into the pitfalls and caveats related to this technique for researchers considering using this dye.
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57
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Kumar L, Cox CR, Sarkar SK. Matrix metalloprotease-1 inhibits and disrupts Enterococcus faecalis biofilms. PLoS One 2019; 14:e0210218. [PMID: 30633757 PMCID: PMC6329490 DOI: 10.1371/journal.pone.0210218] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 12/17/2018] [Indexed: 12/11/2022] Open
Abstract
Enterococcus faecalis is a major opportunistic pathogen that readily forms protective biofilms leading to chronic infections. Biofilms protect bacteria from detergent solutions, antimicrobial agents, environmental stress, and effectively make bacteria 10 to 1000-fold more resistant to antibiotic treatment. Extracellular proteins and polysaccharides are primary components of biofilms and play a key role in cell survival, microbial persistence, cellular interaction, and maturation of E. faecalis biofilms. Degradation of biofilm components by mammalian proteases is an effective antibiofilm strategy because proteases are known to degrade bacterial proteins leading to bacterial cell lysis and growth inhibition. Here, we show that human matrix metalloprotease-1 inhibits and disrupts E. faecalis biofilms. MMPs are cell-secreted zinc- and calcium-dependent proteases that degrade and regulate various structural components of the extracellular matrix. Human MMP1 is known to degrade type-1 collagen and can also cleave a wide range of substrates. We found that recombinant human MMP1 significantly inhibited and disrupted biofilms of vancomycin sensitive and vancomycin resistant E. faecalis strains. The mechanism of antibiofilm activity is speculated to be linked with bacterial growth inhibition and degradation of biofilm matrix proteins by MMP1. These findings suggest that human MMP1 can potentially be used as a potent antibiofilm agent against E. faecalis biofilms.
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Affiliation(s)
- Lokender Kumar
- Department of Physics, Colorado School of Mines, CO, United States of America
| | - Christopher R. Cox
- Department of Chemistry, Colorado School of Mines, CO, United States of America
| | - Susanta K. Sarkar
- Department of Physics, Colorado School of Mines, CO, United States of America
- * E-mail:
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58
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Bacterial Amyloids: Biogenesis and Biomaterials. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1174:113-159. [DOI: 10.1007/978-981-13-9791-2_4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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59
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Galkin AP, Velizhanina ME, Sopova YV, Shenfeld AA, Zadorsky SP. Prions and Non-infectious Amyloids of Mammals - Similarities and Differences. BIOCHEMISTRY (MOSCOW) 2018; 83:1184-1195. [PMID: 30472956 DOI: 10.1134/s0006297918100048] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Amyloids are highly ordered aggregates of protein fibrils exhibiting cross-β structure formed by intermolecular hydrogen bonds. Pathological amyloid deposition is associated with the development of several socially significant incurable human diseases. Of particular interest are infectious amyloids, or prions, that cause several lethal neurodegenerative diseases in humans and can be transmitted from one organism to another. Because of almost complete absence of criteria for infectious and non-infectious amyloids, there is a lack of consensus, especially, in the definition of similarities and differences between prions and non-infectious amyloids. In this review, we formulated contemporary molecular-biological criteria for identification of prions and non-infectious amyloids and focused on explaining the differences between these two types of molecules.
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Affiliation(s)
- A P Galkin
- St. Petersburg Branch of Vavilov Institute of General Genetics, Russian Academy of Sciences, St. Petersburg, 199034, Russia. .,St. Petersburg State University, Department of Genetics and Biotechnology, St. Petersburg, 199034, Russia
| | - M E Velizhanina
- St. Petersburg State University, Department of Genetics and Biotechnology, St. Petersburg, 199034, Russia
| | - Yu V Sopova
- St. Petersburg Branch of Vavilov Institute of General Genetics, Russian Academy of Sciences, St. Petersburg, 199034, Russia.,St. Petersburg State University, Department of Genetics and Biotechnology, St. Petersburg, 199034, Russia
| | - A A Shenfeld
- St. Petersburg Branch of Vavilov Institute of General Genetics, Russian Academy of Sciences, St. Petersburg, 199034, Russia.,St. Petersburg State University, Department of Genetics and Biotechnology, St. Petersburg, 199034, Russia
| | - S P Zadorsky
- St. Petersburg Branch of Vavilov Institute of General Genetics, Russian Academy of Sciences, St. Petersburg, 199034, Russia. .,St. Petersburg State University, Department of Genetics and Biotechnology, St. Petersburg, 199034, Russia
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60
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Dapson RW. Amyloid from a histochemical perspective. A review of the structure, properties and types of amyloid, and a proposed staining mechanism for Congo red staining. Biotech Histochem 2018; 93:543-556. [PMID: 30403893 DOI: 10.1080/10520295.2018.1528385] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
Amyloid is a diverse group of unrelated peptides or proteins that have positive functionality or are associated with various pathologies. Despite vast differences, all amyloids share several features that together uniquely define the group. 1) All amyloids possess a characteristic cross-ß pattern with X-ray diffraction typical of ß-sheet secondary protein structures. 2) All amyloids are birefringent and dichroic under polarizing microscopy after staining with Congo red, which indicates a crystalline-like (ordered) structure. 3) All amyloids cause a spectral shift in the peak wavelength of Congo red with conventional light microscopy due to perturbation of π electrons of the dye. 4) All amyloids show heightened intensity of fluorescence with Congo red, which suggests an unusual degree of packing of the dye onto the substrate. The ß portion of amyloid molecules, the only logical substrate for specific Congo red staining under histochemical conditions, consists of a stack of ß-sheets laminated by hydrophilic and hydrophobic interactions between adjacent pairs. Only the first and last ß-sheets are accessible to dyes. Each sheet is composed of numerous identical peptides running across the width of the sheet and arranged in parallel with side chains in register over the length of the fibril. Two sets of grooves are bordered by side chains. X grooves run perpendicular to the long axis of the fibril; these grooves are short (the width of the sheet) and number in the hundreds or thousands. Y grooves are parallel with the long axis. Each groove runs the entire length of the fibril, but there are very few of them. While Congo red is capable of ionic bonding with proteins via two sulfonic acid groups, physical constraints on the staining solution preclude ionic interactions. Hydrogen bonding between dye amine groups and peptide carbonyls is the most likely primary bonding mechanism, because all ß-sheets possess backbone carbonyls. Various amino acid residues may form secondary bonds to the dye via any of three van der Waals forces. It is possible that Congo red binds within the Y grooves, but that would not produce the characteristic staining features that are the diagnostic hallmarks of amyloid. Binding in the X grooves would produce a tightly packed series of dye molecules over the entire length of the fibril. This would account for the signature staining of amyloid by Congo red: dichroic birefringence, enhanced intensity of fluorescence and a shift in visible absorption wavelength.
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61
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Hasan S, Fatma S, Zaman M, Khan RH, Naeem A. Carboxylic acids of different nature induces aggregation of hemoglobin. Int J Biol Macromol 2018; 118:1584-1593. [DOI: 10.1016/j.ijbiomac.2018.07.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Revised: 07/01/2018] [Accepted: 07/02/2018] [Indexed: 01/28/2023]
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62
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An in-silico method for identifying aggregation rate enhancer and mitigator mutations in proteins. Int J Biol Macromol 2018; 118:1157-1167. [DOI: 10.1016/j.ijbiomac.2018.06.102] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 06/19/2018] [Accepted: 06/20/2018] [Indexed: 12/27/2022]
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63
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Cai J, Sweeney AM. The Proof Is in the Pidan: Generalizing Proteins as Patchy Particles. ACS CENTRAL SCIENCE 2018; 4:840-853. [PMID: 30062112 PMCID: PMC6062823 DOI: 10.1021/acscentsci.8b00187] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Indexed: 05/07/2023]
Abstract
The Chinese century egg, or pidan, is a traditional preparation of duck eggs that can be stored for months at room temperature without degradation. Raw eggs are soaked in a strong alkaline and salt solution, and the albumin gradually forms a stable, transparent gel. Here, we show that pidan gels belong to the class of materials formed from "patchy particles". We found that the β-sheet structure of ovalbumin, the major protein constituent of egg white, is preserved during gelation, while α-helical regions undergo a degree of unfolding into unstructured random coils that may form attractive patches. Upon dilution in additional strong base, the phase behavior of pidan gels is consistent with patchy-particle thermodynamics. This protein gel is also physically and structurally similar to the protein gels that form the squid lens. Both systems exhibit patchy thermodynamics, and the constituent proteins share physical features including a structured, charged core, and polar, unstructured "arms" that form attractive patches. Our work provides a path toward rational design of proteins for precisely structured, volume-spanning materials.
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Affiliation(s)
- Jing Cai
- Department of Physics and
Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Alison M. Sweeney
- Department of Physics and
Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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64
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Van Gerven N, Van der Verren SE, Reiter DM, Remaut H. The Role of Functional Amyloids in Bacterial Virulence. J Mol Biol 2018; 430:3657-3684. [PMID: 30009771 PMCID: PMC6173799 DOI: 10.1016/j.jmb.2018.07.010] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 07/05/2018] [Accepted: 07/06/2018] [Indexed: 12/14/2022]
Abstract
Amyloid fibrils are best known as a product of human and animal protein misfolding disorders, where amyloid formation is associated with cytotoxicity and disease. It is now evident that for some proteins, the amyloid state constitutes the native structure and serves a functional role. These functional amyloids are proving widespread in bacteria and fungi, fulfilling diverse functions as structural components in biofilms or spore coats, as toxins and surface-active fibers, as epigenetic material, peptide reservoirs or adhesins mediating binding to and internalization into host cells. In this review, we will focus on the role of functional amyloids in bacterial pathogenesis. The role of functional amyloids as virulence factor is diverse but mostly indirect. Nevertheless, functional amyloid pathways deserve consideration for the acute and long-term effects of the infectious disease process and may form valid antimicrobial targets. Functional amyloids are widespread in bacteria, pathogenic and non-pathogenic. Bacterial biofilms most commonly function as structural support in the extracellular matrix of biofilms or spore coats, and in cell–cell and cell-surface adherence. The amyloid state can be the sole structured and functional state, or can be facultative, as a secondary state to folded monomeric subunits. Bacterial amyloids can enhance virulence by increasing persistence, cell adherence and invasion, intracellular survival, and pathogen spread by increased environmental survival. Bacterial amyloids may indirectly inflict disease by triggering inflammation, contact phase activation and possibly induce or aggravate human pathological aggregation disorders.
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Affiliation(s)
- Nani Van Gerven
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium; Structural and Molecular Microbiology, Structural Biology Research Center, VIB, Pleinlaan 2, 1050 Brussels, Belgium
| | - Sander E Van der Verren
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium; Structural and Molecular Microbiology, Structural Biology Research Center, VIB, Pleinlaan 2, 1050 Brussels, Belgium
| | - Dirk M Reiter
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium; Structural and Molecular Microbiology, Structural Biology Research Center, VIB, Pleinlaan 2, 1050 Brussels, Belgium
| | - Han Remaut
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium; Structural and Molecular Microbiology, Structural Biology Research Center, VIB, Pleinlaan 2, 1050 Brussels, Belgium.
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65
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Fünfhaus A, Göbel J, Ebeling J, Knispel H, Garcia-Gonzalez E, Genersch E. Swarming motility and biofilm formation of Paenibacillus larvae, the etiological agent of American Foulbrood of honey bees (Apis mellifera). Sci Rep 2018; 8:8840. [PMID: 29892084 PMCID: PMC5995878 DOI: 10.1038/s41598-018-27193-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 05/29/2018] [Indexed: 12/19/2022] Open
Abstract
American Foulbrood is a worldwide distributed, fatal disease of the brood of the Western honey bee (Apis mellifera). The causative agent of this fatal brood disease is the Gram-positive, spore-forming bacterium Paenibacillus larvae, which can be classified into four different genotypes (ERIC I-IV), with ERIC I and II being the ones isolated from contemporary AFB outbreaks. P. larvae is a peritrichously flagellated bacterium and, hence, we hypothesized that P. larvae is capable of coordinated and cooperative multicellular behaviors like swarming motility and biofilm formation. In order to analyze these behaviors of P. larvae, we firstly established appropriate functional assays. Using these assays we demonstrated that P. larvae ERIC II, but not P. larvae ERIC I, was capable of swarming. Swarming motility was hampered in a P. larvae ERIC II-mutant lacking production of paenilarvin, an iturin-like lipopeptide exclusively expressed by this genotype. Both genotypes were able to form free floating biofilm aggregates loosely attached to the walls of the culture wells. Visualizing the biofilms by Congo red and thioflavin S staining suggested structural differences between the biofilms formed. Biofilm formation was shown to be independent from paenilarvin production because the paenilarvin deficient mutant was comparably able to form a biofilm.
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Affiliation(s)
- Anne Fünfhaus
- Institute for Bee Research, Department of Molecular Microbiology and Bee Diseases, Hohen Neuendorf, Germany
| | - Josefine Göbel
- Institute for Bee Research, Department of Molecular Microbiology and Bee Diseases, Hohen Neuendorf, Germany
| | - Julia Ebeling
- Institute for Bee Research, Department of Molecular Microbiology and Bee Diseases, Hohen Neuendorf, Germany
| | - Henriette Knispel
- Institute for Bee Research, Department of Molecular Microbiology and Bee Diseases, Hohen Neuendorf, Germany
| | - Eva Garcia-Gonzalez
- Institute for Bee Research, Department of Molecular Microbiology and Bee Diseases, Hohen Neuendorf, Germany
| | - Elke Genersch
- Institute for Bee Research, Department of Molecular Microbiology and Bee Diseases, Hohen Neuendorf, Germany.
- Freie Universität Berlin, Fachbereich Veterinärmedizin, Institut für Mikrobiologie und Tierseuchen, Berlin, Germany.
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66
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Gusel'nikova V, Antimonova O, Fedorova E, Shavlovsky M, Krutikov A, Mikhailova E, Gudkova A, Mikhailov V, Korzhevskii D. Fluorescent characterization of amyloid deposits in the kidneys of mdx mice. Eur J Histochem 2018; 62:2870. [PMID: 29943948 PMCID: PMC6047883 DOI: 10.4081/ejh.2018.2870] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Revised: 02/11/2018] [Accepted: 02/12/2018] [Indexed: 01/31/2023] Open
Abstract
Amyloidosis is a group of diseases that occurs when amyloid proteins are deposited in tissues and organs. The traditional way of identifying amyloid in tissue sections is staining with Congo red. However, this method has a number of limitations including background staining (background fluorescence), low fluorescence intensity and false-positive staining. Therefore, a complex of fluorescence-based methods should be applied to characterize tissue localization of amyloid deposits. The aim of this study was to identify amyloid deposits in the kidneys of dystrophin-deficient mdx mice using different fluorescent dyes. We examined 8 cases of renal amyloidosis in aged mdx mice. In all cases, we used traditional methods for amyloid detection (Congo red and Thioflavin T), as well as a new fluorescent dye, disodium salt of 2,7- (1-amino-4-sulfo-2-naphthylazo) fluorene (DSNAF). In our study, we confirmed the amyloid structure of protein deposits in kidneys of aging mdx mice by several fluorescence-based staining methods. We found that fixation method has profound effects on downstream staining procedures, and demonstrated that the application of specific fixative, zinc-ethanol-formaldehyde (ZEF), instead of traditional NBF allow to reduce the background fluorescence. We also illustrated the usefulness of novel fluorescent dye DSNAF for detection of amyloid deposits in mouse tissues. Our results confirmed the strong affinity and high specificity of this dye for amyloid fibrils. The verification of DSNAF for detecting amyloid in human tissues will provide a conclusion on the applicability of the developed staining method in clinical research practice.
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67
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Zheng Q, Lazo ND. Mechanistic Studies of the Inhibition of Insulin Fibril Formation by Rosmarinic Acid. J Phys Chem B 2018; 122:2323-2331. [PMID: 29401384 DOI: 10.1021/acs.jpcb.8b00689] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The self-assembly of insulin to form amyloid fibrils has been widely studied because it is a significant problem in the medical management of diabetes and is an important model system for the investigation of amyloid formation and its inhibition. A few inhibitors of insulin fibrillation have been identified with potencies that could be higher. Knowledge of how these work at the molecular level is not known but important for the development of more potent inhibitors. Here we show that rosmarinic acid completely inhibits amyloid formation by dimeric insulin at pH 2 and 60 °C. In contrast to other polyphenols, rosmarinic acid is soluble in water and does not degrade at elevated temperatures, and thus we were able to decipher the mechanism of inhibition by a combination of solution-state 1H NMR spectroscopy and molecular docking. On the basis of 1H chemical shift perturbations, intermolecular nuclear Overhauser effect enhancements between rosmarinic acid and specific residues of insulin, and slowed dynamics of rosmarinic acid in the presence of insulin, we show that rosmarinic acid binds to a pocket found on the surface of each insulin monomer. This results in the formation of a mixed tetramolecular aromatic network on the surface of insulin dimer, resulting in increased resistance of the amyloidogenic protein to thermal unfolding. This finding opens new avenues for the design of potent inhibitors of amyloid formation and provides strong experimental evidence for the role of surface aromatic clusters in increasing the thermal stability of proteins.
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Affiliation(s)
- Qiuchen Zheng
- Carlson School of Chemistry and Biochemistry, Clark University , 950 Main Street, Worcester, Massachusetts 01610, United States
| | - Noel D Lazo
- Carlson School of Chemistry and Biochemistry, Clark University , 950 Main Street, Worcester, Massachusetts 01610, United States
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68
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Flynn JD, McGlinchey RP, Walker RL, Lee JC. Structural features of α-synuclein amyloid fibrils revealed by Raman spectroscopy. J Biol Chem 2018; 293:767-776. [PMID: 29191831 PMCID: PMC5777252 DOI: 10.1074/jbc.m117.812388] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 11/17/2017] [Indexed: 12/24/2022] Open
Abstract
Parkinson's disease (PD) is associated with the formation of α-synuclein amyloid fibrils. Elucidating the role of these β-sheet-rich fibrils in disease progression is crucial; however, collecting detailed structural information on amyloids is inherently difficult because of their insoluble, non-crystalline, and polymorphic nature. Here, we show that Raman spectroscopy is a facile technique for characterizing structural features of α-synuclein fibrils. Combining Raman spectroscopy with aggregation kinetics and transmission electron microscopy, we examined the effects of pH and ionic strength as well as four PD-related mutations (A30P, E46K, G51D, and A53T) on α-synuclein fibrils. Raman spectral differences were observed in the amide-I, amide-III, and fingerprint regions, indicating that secondary structure and tertiary contacts are influenced by pH and to a lesser extent by NaCl. Faster aggregation times appear to facilitate unique fibril structure as determined by the highly reproducible amide-I band widths, linking aggregation propensity and fibril polymorphism. Importantly, Raman spectroscopy revealed molecular-level perturbations of fibril conformation by the PD-related mutations that are not apparent through transmission electron microscopy or limited proteolysis. The amide-III band was found to be particularly sensitive, with G51D exhibiting the most distinctive features, followed by A53T and E46K. Relating to a cellular environment, our data would suggest that fibril polymorphs can be formed in different cellular compartments and potentially result in distinct phenotypes. Our work sets a foundation toward future cellular Raman studies of amyloids.
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Affiliation(s)
- Jessica D Flynn
- From the Laboratory of Protein Conformation and Dynamics, Biochemistry and Biophysics Center, NHLBI, National Institutes of Health, Bethesda, Maryland 20892
| | - Ryan P McGlinchey
- From the Laboratory of Protein Conformation and Dynamics, Biochemistry and Biophysics Center, NHLBI, National Institutes of Health, Bethesda, Maryland 20892
| | - Robert L Walker
- From the Laboratory of Protein Conformation and Dynamics, Biochemistry and Biophysics Center, NHLBI, National Institutes of Health, Bethesda, Maryland 20892
| | - Jennifer C Lee
- From the Laboratory of Protein Conformation and Dynamics, Biochemistry and Biophysics Center, NHLBI, National Institutes of Health, Bethesda, Maryland 20892
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69
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Nusrat S, Khan RH. Exploration of ligand-induced protein conformational alteration, aggregate formation, and its inhibition: A biophysical insight. Prep Biochem Biotechnol 2018; 48:43-56. [PMID: 29106330 DOI: 10.1080/10826068.2017.1387561] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The association of protein aggregates with plentiful human diseases has fascinated studies regarding the biophysical characterization of protein misfolding and ultimately their aggregate formation mechanism. Protein-ligand interaction, their mechanism, conformational changes by ligands, and protein aggregate formation have been studied upon exploiting experimental techniques and computational methodologies. Such studies for the exploration of ligand-induced conformational changes in protein, misfolding and aggregation, has confirmed drastic progresses in the study of aggregate formation pathways. This review comprises of an inclusive description of contemporary experimental techniques as well as theoretical improvements in the interpretation of the conformational properties of protein. We have also discussed various factors responsible for the microenvironment change around protein that sequentially causes amyloidoses. Biophysical techniques and cell-based assays to gain comprehensive understandings of protein-ligand interaction, protein folding, and aggregation pathways have also been described. The promising therapeutic methods used to inhibit the protein fibrillogenesis have also been discussed.
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Affiliation(s)
- Saima Nusrat
- a Interdisciplinary Biotechnology Unit , Aligarh Muslim University , Aligarh , Uttar Pradesh , India
| | - Rizwan Hasan Khan
- a Interdisciplinary Biotechnology Unit , Aligarh Muslim University , Aligarh , Uttar Pradesh , India
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70
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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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71
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Ansari MZ, Kumar A, Ahari D, Priyadarshi A, Lolla P, Bhandari R, Swaminathan R. Protein charge transfer absorption spectra: an intrinsic probe to monitor structural and oligomeric transitions in proteins. Faraday Discuss 2018; 207:91-113. [DOI: 10.1039/c7fd00194k] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The utility of ProCharTS as an intrinsic spectral probe to track protein aggregation and monitor conformational changes is reported.
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Affiliation(s)
- Mohd. Ziauddin Ansari
- Department of Biosciences & Bioengineering
- Indian Institute of Technology Guwahati
- Guwahati 781039
- India
| | - Amrendra Kumar
- Department of Biosciences & Bioengineering
- Indian Institute of Technology Guwahati
- Guwahati 781039
- India
| | - Dileep Ahari
- Department of Biosciences & Bioengineering
- Indian Institute of Technology Guwahati
- Guwahati 781039
- India
| | - Anurag Priyadarshi
- Department of Biosciences & Bioengineering
- Indian Institute of Technology Guwahati
- Guwahati 781039
- India
| | - Padmavathi Lolla
- Laboratory of Cell Signalling
- Centre for DNA Fingerprinting and Diagnostics (CDFD)
- Hyderabad 500001
- India
| | - Rashna Bhandari
- Laboratory of Cell Signalling
- Centre for DNA Fingerprinting and Diagnostics (CDFD)
- Hyderabad 500001
- India
| | - Rajaram Swaminathan
- Department of Biosciences & Bioengineering
- Indian Institute of Technology Guwahati
- Guwahati 781039
- India
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72
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Mukherjee M, Jana J, Chatterjee S. A Small Molecule Impedes Insulin Fibrillation: Another New Role of Phenothiazine Derivatives. ChemistryOpen 2018; 7:68-79. [PMID: 29318099 PMCID: PMC5754551 DOI: 10.1002/open.201700131] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 08/24/2017] [Indexed: 11/16/2022] Open
Abstract
Protein misfolding is interrelated to several diseases, including neurodegenerative diseases and type II diabetes. Misfolded/unfolded proteins produce soluble oligomers that accumulate into "amyloid plaques". Inhibition of amyloid-plaque formation by those misfolded/unfolded proteins will lead to the invention of new therapeutic approaches for amyloid-related diseases. Herein, methylene blue (MB), a well-defined drug against multiple diseases and disorders, is used to impede insulin fibrillation. In this study, we perform an array of in vitro experiments to monitor the effects of MB on the fibrillation of bovine insulin. Our results confirm that MB distresses the kinetics of insulin fibrillation by interacting with insulin in its monomeric form. A thioflavin T assay indicates that insulin fibrillation is interrupted upon the addition of MB. The same results are confirmed by circular dichroism, dynamic light scattering (DLS), and size-exclusion chromatography (SEC). According to the DLS data, the insulin fibrils are 800 nm in diameter, and the addition of MB reduces the size of the fibrils, which remain 23 nm in size, and this indicates that no fibrillation of insulin occurs in the presence of MB. This data is also supported by SEC. Saturation transfer difference NMR spectroscopy and molecular dynamics simulations demonstrate the interactions between insulin and MB at the atomic level.
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Affiliation(s)
- Meghomukta Mukherjee
- Department of BiophysicsBose Institute, P 1/12 CIT, Scheme VII MKankurgachiKolkata700054India
| | - Jagannath Jana
- Department of BiophysicsBose Institute, P 1/12 CIT, Scheme VII MKankurgachiKolkata700054India
| | - Subhrangsu Chatterjee
- Department of BiophysicsBose Institute, P 1/12 CIT, Scheme VII MKankurgachiKolkata700054India
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73
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Gowda C, Zandomeneghi G, Zimmermann H, Schütz AK, Böckmann A, Ernst M, Meier BH. The conformation of the Congo-red ligand bound to amyloid fibrils HET-s(218-289): a solid-state NMR study. JOURNAL OF BIOMOLECULAR NMR 2017; 69:207-213. [PMID: 29094285 DOI: 10.1007/s10858-017-0148-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Accepted: 10/21/2017] [Indexed: 06/07/2023]
Abstract
We have previously shown that Congo red (CR) binds site specifically to amyloid fibrils formed by HET-s(218-289) with the long axis of the CR molecule almost parallel to the fibril axis. HADDOCK docking studies indicated that CR adopts a roughly planar conformation with the torsion angle ϕ characterizing the relative orientation of the two phenyl rings being a few degrees. In this study, we experimentally determine the torsion angle ϕ at the center of the CR molecule when bound to HET-s(218-289) amyloid fibrils using solid-state NMR tensor-correlation experiments. The method described here relies on the site-specific 13C labeling of CR and on the analysis of the two-dimensional magic-angle spinning tensor-correlation spectrum of 13C2-CR. We determined the torsion angle ϕ to be 19°.
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Affiliation(s)
| | | | - Herbert Zimmermann
- Department of Biomolecular Mechanisms, Max-Planck-Institut für medizinische Forschung, Jahnstr. 29, 69120, Heidelberg, Germany
| | - Anne K Schütz
- Physical Chemistry, ETH Zurich, 8093, Zurich, Switzerland
| | - Anja Böckmann
- IBCP, UMR 5086 CNRS/Université de Lyon 1, 7 Passage du Vercors, 69367, Lyon, France
| | - Matthias Ernst
- Physical Chemistry, ETH Zurich, 8093, Zurich, Switzerland.
| | - Beat H Meier
- Physical Chemistry, ETH Zurich, 8093, Zurich, Switzerland.
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74
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Hiew SH, Sánchez-Ferrer A, Amini S, Zhou F, Adamcik J, Guerette P, Su H, Mezzenga R, Miserez A. Squid Suckerin Biomimetic Peptides Form Amyloid-like Crystals with Robust Mechanical Properties. Biomacromolecules 2017; 18:4240-4248. [PMID: 29112414 DOI: 10.1021/acs.biomac.7b01280] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
We present the self-assembly of fibers formed from a peptide sequence (A1H1) derived from suckerin proteins of squid sucker ring teeth (SRT). SRT are protein-only biopolymers with an unconventional set of physicochemical and mechanical properties including high elastic modulus coupled with thermoplastic behavior. We have identified a conserved peptide building block from suckerins that possess the ability to assemble into materials with similar mechanical properties as the native SRT. A1H1 displays amphiphilic characteristics and self-assembles from the bottom-up into mm-scale fibers initiated by the addition of a polar aprotic solvent. A1H1 fibers are thermally resistant up to 239 °C, coupled with an elastic modulus of ∼7.7 GPa, which can be explained by the tight packing of β-sheet-enriched crystalline building blocks as identified by wide-angle X-ray scattering (WAXS), with intersheet and interstrand distances of 5.37 and 4.38 Å, respectively. A compact packing of the peptides at their Ala-rich terminals within the fibers was confirmed from molecular dynamics simulations, and we propose a hierarchical model of fiber assembly of the mature peptide fiber.
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Affiliation(s)
- Shu Hui Hiew
- School of Materials Science and Engineering, Nanyang Technological University , Singapore 639798, Singapore
| | - Antoni Sánchez-Ferrer
- Department of Health Sciences & Technology, ETH Zurich , Zurich CH-8092, CH-8093, Switzerland
| | - Shahrouz Amini
- School of Materials Science and Engineering, Nanyang Technological University , Singapore 639798, Singapore
| | - Feng Zhou
- School of Materials Science and Engineering, Nanyang Technological University , Singapore 639798, Singapore
| | - Jozef Adamcik
- Department of Health Sciences & Technology, ETH Zurich , Zurich CH-8092, CH-8093, Switzerland
| | - Paul Guerette
- School of Materials Science and Engineering, Nanyang Technological University , Singapore 639798, Singapore
| | - Haibin Su
- School of Materials Science and Engineering, Nanyang Technological University , Singapore 639798, Singapore
| | - Raffaele Mezzenga
- Department of Health Sciences & Technology, ETH Zurich , Zurich CH-8092, CH-8093, Switzerland
| | - Ali Miserez
- School of Materials Science and Engineering, Nanyang Technological University , Singapore 639798, Singapore.,School of Biological Sciences, Nanyang Technological University , Singapore 637551, Singapore
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75
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Subbalakshmi C, Basak P, Nagaraj R. Self-assembly of t-butyloxycarbonyl protected dipeptide methyl esters composed of leucine, isoleucine, and valine into highly organized structures from alcohol and aqueous alcohol mixtures. Biopolymers 2017; 108. [DOI: 10.1002/bip.23033] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 05/05/2017] [Accepted: 05/26/2017] [Indexed: 01/13/2023]
Affiliation(s)
- Chivukula Subbalakshmi
- CSIR-Centre for Cellular and Molecular Biology; Uppal Road; Hyderabad Telangana 500007 India
| | - Pratyay Basak
- Nanomaterials Laboratory, Inorganic & Physical Chemistry Division; CSIR-Indian Institute of Chemical Technology, Uppal Road; Hyderabad Telangana 500007 India
| | - Ramakrishnan Nagaraj
- CSIR-Centre for Cellular and Molecular Biology; Uppal Road; Hyderabad Telangana 500007 India
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76
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Khan MA, Arif Z, Moinuddin, Alam K. Characterization of methylglyoxal-modified human IgG by physicochemical methods. J Biomol Struct Dyn 2017; 36:3172-3183. [DOI: 10.1080/07391102.2017.1383309] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Mohd. Adnan Khan
- Department of Biochemistry, Faculty of Medicine, Aligarh Muslim University, Aligarh, UP 202002, India
| | - Zarina Arif
- Department of Biochemistry, Faculty of Medicine, Aligarh Muslim University, Aligarh, UP 202002, India
| | - Moinuddin
- Department of Biochemistry, Faculty of Medicine, Aligarh Muslim University, Aligarh, UP 202002, India
| | - Khursheed Alam
- Department of Biochemistry, Faculty of Medicine, Aligarh Muslim University, Aligarh, UP 202002, India
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77
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Lessons learned from protein aggregation: toward technological and biomedical applications. Biophys Rev 2017; 9:501-515. [PMID: 28905328 DOI: 10.1007/s12551-017-0317-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2017] [Accepted: 08/08/2017] [Indexed: 12/21/2022] Open
Abstract
The close relationship between protein aggregation and neurodegenerative diseases has been the driving force behind the renewed interest in a field where biophysics, neurobiology and nanotechnology converge in the study of the aggregate state. On one hand, knowledge of the molecular principles that govern the processes of protein aggregation has a direct impact on the design of new drugs for high-incidence pathologies that currently can only be treated palliatively. On the other hand, exploiting the benefits of protein aggregation in the design of new nanomaterials could have a strong impact on biotechnology. Here we review the contributions of our research group on novel neuroprotective strategies developed using a purely biophysical approach. First, we examine how doxycycline, a well-known and innocuous antibiotic, can reshape α-synuclein oligomers into non-toxic high-molecular-weight species with decreased ability to destabilize biological membranes, affect cell viability and form additional toxic species. This mechanism can be exploited to diminish the toxicity of α-synuclein oligomers in Parkinson's disease. Second, we discuss a novel function in proteostasis for extracellular glyceraldehyde 3-phosphate dehydrogenase (GAPDH) in combination with a specific glycosaminoglycan (GAG) present in the extracellular matrix. GAPDH, by changing its quaternary structure from a tetramer to protofibrillar assembly, can kidnap toxic species of α-synuclein, and thereby interfere with the spreading of the disease. Finally, we review a brighter side of protein aggregation, that of exploiting the physicochemical advantages of amyloid aggregates as nanomaterials. For this, we designed a new generation of insoluble biocatalysts based on the binding of photo-immobilized enzymes onto hybrid protein:GAG amyloid nanofibrils. These new nanomaterials can be easily functionalized by attaching different enzymes through dityrosine covalent bonds.
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78
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Zhang J, Sandberg A, Wu X, Nyström S, Lindgren M, Konradsson P, Hammarström P. trans-Stilbenoids with Extended Fluorescence Lifetimes for the Characterization of Amyloid Fibrils. ACS OMEGA 2017; 2:4693-4704. [PMID: 31457755 PMCID: PMC6641930 DOI: 10.1021/acsomega.7b00535] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Accepted: 07/13/2017] [Indexed: 05/29/2023]
Abstract
It was previously reported that two naphthyl-based trans-stilbene probes, (E)-4-(2-(naphthalen-1-yl)vinyl)benzene-1,2-diol (1) and (E)-4-(2-(naphthalen-2-yl)vinyl)benzene-1,2-diol (3), can bind to both native transthyretin (TTR) and misfolded protofibrillar TTR at physiological concentrations, displaying distinct emission maxima bound to the different conformational states (>100 nm difference). To further explore this amyloid probe scaffold to obtain extended fluorescence lifetimes, two new analogues with expanded aromatic ring systems (anthracene and pyrene), (E)-4-(2-(anthracen-2-yl)vinyl)benzene-1,2-diol (4) and (E)-4-(2-(pyren-2-yl)vinyl)benzene-1,2-diol (5), were synthesized employing the palladium-catalyzed Mizoroki-Heck reaction. (E)-4-Styrylbenzene-1,2-diol (2), 3, 4, and 5 were investigated with respect to their photophysical properties in methanol and when bound to insulin, lysozyme, and Aβ1-42 fibrils, including time-resolved fluorescence measurements. In conclusion, 4 and 5 can bind to both native and fibrillar TTR, becoming highly fluorescent. Compounds 2-5 bind specifically to insulin, lysozyme, and Aβ1-42 fibrils with an apparent fluorescence intensity increase and moderate binding affinities. The average fluorescence lifetimes of the probes bound to Aβ1-42 fibrils are 1.3 ns (2), 1.5 ns (3), 5.7 ns (4), and 29.8 ns (5). In summary, the variable aromatic moieties of the para-positioned trans-stilbenoid vinyl-benzene-1,2-diol with benzene, naphthalene, anthracene, and pyrene showed that the extended conjugated systems retained the amyloid targeting properties of the probes. Furthermore, both the anthracene and pyrene moieties extensively enhanced the fluorescence intensity and prolonged lifetimes. These attractive probe properties should improve amyloid detection and characterization by fluorescence-based techniques.
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Affiliation(s)
- Jun Zhang
- IFM-Department
of Chemistry, Linköping University, Linköping 581 83, Sweden
| | - Alexander Sandberg
- IFM-Department
of Chemistry, Linköping University, Linköping 581 83, Sweden
| | - Xiongyu Wu
- IFM-Department
of Chemistry, Linköping University, Linköping 581 83, Sweden
| | - Sofie Nyström
- IFM-Department
of Chemistry, Linköping University, Linköping 581 83, Sweden
| | - Mikael Lindgren
- Department
of Physics, The Norwegian University of
Science and Technology, 7491 Trondheim, Norway
| | - Peter Konradsson
- IFM-Department
of Chemistry, Linköping University, Linköping 581 83, Sweden
| | - Per Hammarström
- IFM-Department
of Chemistry, Linköping University, Linköping 581 83, Sweden
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79
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Kumar M, Hong Y, Thorn DC, Ecroyd H, Carver JA. Monitoring Early-Stage Protein Aggregation by an Aggregation-Induced Emission Fluorogen. Anal Chem 2017; 89:9322-9329. [DOI: 10.1021/acs.analchem.7b02090] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Manjeet Kumar
- Research
School of Chemistry, The Australian National University, Acton, ACT 2601 Australia
| | - Yuning Hong
- Department
of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC 3086 Australia
- School of
Chemistry, The University of Melbourne, Parkville, VIC 3010 Australia
| | - David C. Thorn
- Research
School of Chemistry, The Australian National University, Acton, ACT 2601 Australia
| | - Heath Ecroyd
- School
of Biological Sciences and the Illawarra Health and Medical Research
Institute, University of Wollongong, Wollongong NSW 2522 Australia
| | - John A. Carver
- Research
School of Chemistry, The Australian National University, Acton, ACT 2601 Australia
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80
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Hoepfner J, Kleinsorge M, Papp O, Alfken S, Heiringhoff R, Pich A, Sauer V, Zibert A, Göhring G, Schmidt H, Sgodda M, Cantz T. In vitro modelling of familial amyloidotic polyneuropathy allows quantitative detection of transthyretin amyloid fibril-like structures in hepatic derivatives of patient-specific induced pluripotent stem cells. Biol Chem 2017; 398:939-954. [DOI: 10.1515/hsz-2016-0258] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 12/22/2016] [Indexed: 01/04/2023]
Abstract
Abstract
The transthyretin protein is thermodynamically destabilised by mutations in the transthyretin gene, promoting the formation of amyloid fibrils in various tissues. Consequently, impaired autonomic organ function is observed in patients suffering from transthyretin-related familial amyloidotic polyneuropathy (FAP). The influence of individual genetic backgrounds on fibril formation as a potential cause of genotype-phenotype variations needs to be investigated in order to ensure efficient patient-specific therapies. We reprogrammed FAP patient fibroblasts to induced pluripotent stem (iPS) cells and differentiated these cells into transthyretin-expressing hepatocyte-like cells (HLCs). HLCs differentiated from FAP iPS cells and healthy control iPS cells secreted the transthyretin protein in similar concentrations. Mass spectrometry revealed the presence of mutant transthyretin protein in FAP HLC supernatants. In comparison to healthy control iPS cells, we demonstrated the formation of transthyretin amyloid fibril-like structures in FAP HLC supernatants using the amyloid-specific dyes Congo red and thioflavin T. These dyes were also applicable for the quantitative determination of in vitro formed transthyretin fibril-like structures. Moreover, we confirmed the inhibition of fibril formation by the TTR kinetic stabiliser diclofenac. Thioflavin T fluorescence intensity measurements even allowed the quantification of amyloid fibril-like structures in 96-well plate formats as a prerequisite for patient-specific drug screening approaches.
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81
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Lin S, Mortimer M, Chen R, Kakinen A, Riviere JE, Davis TP, Ding F, Ke PC. NanoEHS beyond Toxicity - Focusing on Biocorona. ENVIRONMENTAL SCIENCE. NANO 2017; 7:1433-1454. [PMID: 29123668 PMCID: PMC5673284 DOI: 10.1039/c6en00579a] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The first phase of environmental health and safety of nanomaterials (nanoEHS) studies has been mainly focused on evidence-based investigations that probe the impact of nanoparticles, nanomaterials and nano-enabled products on biological and ecological systems. The integration of multiple disciplines, including colloidal science, nanomaterial science, chemistry, toxicology/immunology and environmental science, is necessary to understand the implications of nanotechnology for both human health and the environment. While strides have been made in connecting the physicochemical properties of nanomaterials with their hazard potential in tiered models, fundamental understanding of nano-biomolecular interactions and their implications for nanoEHS is largely absent from the literature. Research on nano-biomolecular interactions within the context of natural systems not only provides important clues for deciphering nanotoxicity and nanoparticle-induced pathology, but also presents vast new opportunities for screening beneficial material properties and designing greener products from bottom up. This review highlights new opportunities concerning nano-biomolecular interactions beyond the scope of toxicity.
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Affiliation(s)
- Sijie Lin
- College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Monika Mortimer
- Bren School of Environmental Science and Management, Earth Research Institute and University of California Center for the Environmental Implications of Nanotechnology (UC CEIN), University of California, Santa Barbara, California 93106, United States
| | - Ran Chen
- Nanotechnology Innovation Center of Kansas State, Kansas State University, Manhattan, Kansas 66506, United States
| | - Aleksandr Kakinen
- ARC Center of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Jim E. Riviere
- Nanotechnology Innovation Center of Kansas State, Kansas State University, Manhattan, Kansas 66506, United States
| | - Thomas P. Davis
- ARC Center of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
- Department of Chemistry, University of Warwick, Gibbet Hill, Coventry, CV4 7AL, United Kingdom
| | - Feng Ding
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, United States
| | - Pu Chun Ke
- ARC Center of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
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Bäcklund FG, Elfwing A, Musumeci C, Ajjan F, Babenko V, Dzwolak W, Solin N, Inganäs O. Conducting microhelices from self-assembly of protein fibrils. SOFT MATTER 2017; 13:4412-4417. [PMID: 28590474 DOI: 10.1039/c7sm00068e] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Herein we utilize insulin to prepare amyloid based chiral helices with either right or left handed helicity. We demonstrate that the helices can be utilized as structural templates for the conducting polymer alkoxysulfonate poly(ethylenedioxythiophene) (PEDOT-S). The chirality of the helical assembly is transferred to PEDOT-S as demonstrated by polarized optical microscopy (POM) and Circular Dichroism (CD). Analysis of the helices by conductive atomic force microscopy (c-AFM) shows significant conductivity. In addition, the morphology of the template structure is stabilized by PEDOT-S. These conductive helical structures represent promising candidates in our quest for THz resonators.
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Affiliation(s)
- Fredrik G Bäcklund
- Department of Physics, Chemistry, and Biology, Biomolecular and Organic Electronics, Linköping University, 581 83 Linköping, Sweden.
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Hahn K, Nilsson KPR, Hammarström P, Urban P, Meliss RR, Behrens HM, Krüger S, Röcken C. Establishing and validating the fluorescent amyloid ligand h-FTAA (heptamer formyl thiophene acetic acid) to identify transthyretin amyloid deposits in carpal tunnel syndrome. Amyloid 2017; 24:78-86. [PMID: 28434259 DOI: 10.1080/13506129.2017.1316711] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Transthyretin-derived (ATTR) amyloidosis is a frequent finding in carpal tunnel syndrome. We tested the following hypotheses: the novel fluorescent amyloid ligand heptameric formic thiophene acetic acid (h-FTAA) has a superior sensitivity for the detection of amyloid compared with Congo red-staining; Amyloid load correlates with patient gender and/or patient age. We retrieved 208 resection specimens obtained from 184 patients with ATTR amyloid in the carpal tunnel. Serial sections were stained with Congo red, h-FTAA and an antibody directed against transthyretin (TTR). Stained sections were digitalized and forwarded to computational analyses. The amount of amyloid was correlated with patient demographics. Amyloid stained intensely with h-FTAA and an anti-TTR-antibody. Congo red-staining combined with fluorescence microscopy was significantly less sensitive than h-FTAA-fluorescence and TTR-immunostaining: the highest percentage area was found in TTR-immunostained sections, followed by h-FTAA and Congo red. The Pearson correlation coefficient was .8 (Congo red vs. h-FTAA) and .9 (TTR vs. h-FTAA). Amyloid load correlated with patient gender, anatomical site and patient age. h-FTAA is a highly sensitive method to detect even small amounts of ATTR amyloid in the carpal tunnel. The staining protocol is easy and h-FTAA may be a much more sensitive procedure to detect amyloid at an earlier stage.
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Affiliation(s)
- Katharina Hahn
- a Department of Pathology , Christian-Albrechts-University Kiel, Kiel , Germany
| | - K Peter R Nilsson
- b IFM-Department of Chemistry , Linkoping University , Linköping, Sweden
| | - Per Hammarström
- b IFM-Department of Chemistry , Linkoping University , Linköping, Sweden
| | - Peter Urban
- c Institute of Pathology and Dermatopathology , Gehrden, Germany
| | | | | | - Sandra Krüger
- a Department of Pathology , Christian-Albrechts-University Kiel, Kiel , Germany
| | - Christoph Röcken
- a Department of Pathology , Christian-Albrechts-University Kiel, Kiel , Germany
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84
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Furkan M, Alam MT, Rizvi A, Khan K, Ali A, Naeem A. Aloe emodin, an anthroquinone from Aloe vera acts as an anti aggregatory agent to the thermally aggregated hemoglobin. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2017; 179:188-193. [PMID: 28242448 DOI: 10.1016/j.saa.2017.02.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Revised: 02/04/2017] [Accepted: 02/05/2017] [Indexed: 06/06/2023]
Abstract
Aggregation of proteins is a physiological process which contributes to the pathophysiology of several maladies including diabetes mellitus, Huntington's and Alzheimer's disease. In this study we have reported that aloe emodin (AE), an anthroquinone, which is one of the active components of the Aloe vera plant, acts as an inhibitor of hemoglobin (Hb) aggregation. Hb was thermally aggregated at 60°C for four days as evident by increased thioflavin T and ANS fluorescence, shifted congo red absorbance, appearance of β sheet structure, increase in turbidity and presence of oligomeric aggregates. Increasing concentration of AE partially reverses the aggregation of the model heme protein (hemoglobin). The maximum effect of AE was observed at 100μM followed by saturation at 125μM. The results were confirmed by UV-visible spectrometry, intrinsic fluorescence, ThT, ANS, congo red assay as well as transmission electron microscopy (TEM). These results were also supported by fourier transform infrared spectroscopy (FTIR) and circular dichroism (CD) which shows the disappearance of β sheet structure and appearance of α helices. This study will serve as baseline for translatory research and the development of AE based therapeutics for diseases attributed to protein aggregation.
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Affiliation(s)
- Mohammad Furkan
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, India
| | - Md Tauqir Alam
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, India
| | - Asim Rizvi
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, India
| | - Kashan Khan
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, India
| | - Abad Ali
- Department of Chemistry, Faculty of Science, Aligarh Muslim University, Aligarh 202002, India
| | - Aabgeena Naeem
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, India.
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85
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Synthetic food additive dye “Tartrazine” triggers amorphous aggregation in cationic myoglobin. Int J Biol Macromol 2017; 98:277-286. [DOI: 10.1016/j.ijbiomac.2017.01.097] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 12/27/2016] [Accepted: 01/23/2017] [Indexed: 12/18/2022]
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Castellani C, Fedrigo M, Frigo AC, Barbera MD, Thiene G, Valente M, Adami F, Angelini A. Application of confocal laser scanning microscopy for the diagnosis of amyloidosis. Virchows Arch 2017; 470:455-463. [PMID: 28220300 DOI: 10.1007/s00428-017-2081-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 11/10/2016] [Accepted: 01/30/2017] [Indexed: 01/28/2023]
Abstract
We analysed specificity and sensitivity of confocal laser microscopy (CLSM) on tissue sections for a diagnosis of amyloidosis, in an attempt to reduce technical errors and better standardise pathological diagnosis. We first set up a protocol for the use of CLSM on this type of specimen, using a group of 20 amyloid negative and 20 positive samples. Of all specimens, 2, 4 and 8-μm sections were cut. Sections were stained with Congo red (CR) and thioflavin-T (ThT) and observed by cross-polarised light microscopy (CR-PL), epifluorescence microscopy (CRF-epiFM and ThT-epiFM) and CLSM (CRF-CLSM and ThT-CLSM). To validate the method in a diagnostic setting, we examined tissue samples from 116 consecutive patients with clinical suspicion of amyloidosis, selected from the period 2005 to 2014 from the database of the Pathology Unit of the University of Padua. The results were compared with those of transmission electron microscopy (TEM), which we consider as reference. We found that with CRF-CLSM, the false negative rate was reduced from 17 to 5%, while the sensitivity of detection increased to 12%. The results were in complete agreement with those of TEM ThT-CLSM; both sensitivity and specificity were 100%. Finally, ThT-CLSM results did not vary with section thickness, and small amounts of amyloid could even be detected in 2-μm sections. In conclusion, we found ThT-CLSM to be more sensitive as a screening method for amyloidosis than CR and ThT epifluorescence optical imaging. The method was easier to standardise, provided images with better resolution and resulted in more consistent pathologist diagnoses.
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Affiliation(s)
- Chiara Castellani
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padua, Via Gabelli 61, 35100, Padova, Italy
| | - Marny Fedrigo
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padua, Via Gabelli 61, 35100, Padova, Italy
| | - Anna Chiara Frigo
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padua, Via Gabelli 61, 35100, Padova, Italy
| | - Mila Della Barbera
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padua, Via Gabelli 61, 35100, Padova, Italy
| | - Gaetano Thiene
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padua, Via Gabelli 61, 35100, Padova, Italy
| | - Marialuisa Valente
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padua, Via Gabelli 61, 35100, Padova, Italy
| | - Fausto Adami
- Department of Clinical and Experimental Medicine, University of Padua, Padua, Italy
| | - Annalisa Angelini
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padua, Via Gabelli 61, 35100, Padova, Italy.
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87
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Hiew SH, Guerette PA, Zvarec OJ, Phillips M, Zhou F, Su H, Pervushin K, Orner BP, Miserez A. Modular peptides from the thermoplastic squid sucker ring teeth form amyloid-like cross-β supramolecular networks. Acta Biomater 2016; 46:41-54. [PMID: 27693688 DOI: 10.1016/j.actbio.2016.09.040] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Revised: 09/23/2016] [Accepted: 09/28/2016] [Indexed: 12/22/2022]
Abstract
The hard sucker ring teeth (SRT) from decapodiforme cephalopods, which are located inside the sucker cups lining the arms and tentacles of these species, have recently emerged as a unique model structure for biomimetic structural biopolymers. SRT are entirely composed of modular, block co-polymer-like proteins that self-assemble into a large supramolecular network. In order to unveil the molecular principles behind SRT's self-assembly and robustness, we describe a combinatorial screening assay that maps the molecular-scale interactions between the most abundant modular peptide blocks of suckerin proteins. By selecting prominent interaction hotspots from this assay, we identified four peptides that exhibited the strongest homo-peptidic interactions, and conducted further in-depth biophysical characterizations complemented by molecular dynamic (MD) simulations to investigate the nature of these interactions. Circular Dichroism (CD) revealed conformations that transitioned from semi-extended poly-proline II (PII) towards β-sheet structure. The peptides spontaneously self-assembled into microfibers enriched with cross β-structures, as evidenced by Fourier-Transform Infrared Spectroscopy (FTIR) and Congo red staining. Nuclear Magnetic Resonance (NMR) experiments identified the residues involved in the hydrogen-bonded network and demonstrated that these self-assembled β-sheet-based fibers exhibit high protection factors that bear resemblance to amyloids. The high stability of the β-sheet network and an amyloid-like model of fibril assembly were supported by MD simulations. The work sheds light on how Nature has evolved modular sequence design for the self-assembly of mechanically robust functional materials, and expands our biomolecular toolkit to prepare load-bearing biomaterials from protein-based block co-polymers and self-assembled peptides. STATEMENT OF SIGNIFICANCE The sucker ring teeth (SRT) located on the arms and tentacles of cephalopods represent as a very promising protein-based biopolymer with the potential to rival silk in biomedical and engineering applications. SRT are made of modular, block co-polymer like proteins (suckerins), which assemble into a semicrystalline polymer reinforced by nano-confined β-sheets, resulting in a supramolecular network with mechanical properties that match those of the strongest engineering polymers. In this study, we aimed to understand the molecular mechanisms behind SRT's self-assembly and robustness. The most abundant modular peptidic blocks of suckerin proteins were studied by various spectroscopic methods, which demonstrate that SRT peptides form amyloid-like cross-β structures.
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88
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Peccati F, Pantaleone S, Solans-Monfort X, Sodupe M. Fluorescent Markers for Amyloid-β Detection: Computational Insights. Isr J Chem 2016. [DOI: 10.1002/ijch.201600114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Francesca Peccati
- Departament de Química; Universitat Autònoma de Barcelona; 08193 Bellaterra Spain
| | - Stefano Pantaleone
- Departament de Química; Universitat Autònoma de Barcelona; 08193 Bellaterra Spain
| | | | - Mariona Sodupe
- Departament de Química; Universitat Autònoma de Barcelona; 08193 Bellaterra Spain
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89
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Girych M, Gorbenko G, Maliyov I, Trusova V, Mizuguchi C, Saito H, Kinnunen P. Combined thioflavin T-Congo red fluorescence assay for amyloid fibril detection. Methods Appl Fluoresc 2016; 4:034010. [PMID: 28355156 DOI: 10.1088/2050-6120/4/3/034010] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Fluorescence represents one of the most powerful tools for the detection and structural characterization of the pathogenic protein aggregates, amyloid fibrils. The traditional approaches to the identification and quantification of amyloid fibrils are based on monitoring the fluorescence changes of the benzothiazole dye thioflavin T (ThT) and absorbance changes of the azo dye Congo red (CR). In routine screening it is usually sufficient to perform only the ThT and CR assays, but both of them, when used separately, could give false results. Moreover, fibrillization kinetics can be measured only by ThT fluorescence, while the characteristic absorption spectra and birefringence of CR represent more rigid criteria for the presence of amyloid fibrils. Therefore, it seemed reasonable to use both these dyes simultaneously, combining the advantages of each technique. To this end, we undertook a detailed analysis of the fluorescence spectral behavior of these unique amyloid tracers upon their binding to amyloid fibrils from lysozyme, insulin and an N-terminal fragment of apolipoprotein A-I with Iowa mutation. The fluorescence measurements revealed several criteria for distinguishing between fibrillar and monomeric protein states: (i) a common drastic increase in ThT fluorescence intensity; (ii) a sharp decrease in ThT fluorescence upon addition of CR; (iii) an appearance of the maximum at 535-540 nm in the CR excitation spectra; (iv) increase in CR fluorescence intensity at 610 nm. Based on these findings we designed a novel combined ThT-CR fluorescence assay for amyloid identification. Such an approach not only strengthens the reliability of the ThT assay, but also provides new opportunities for structural characterization of amyloid fibrils.
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Affiliation(s)
- Mykhailo Girych
- Department of Nuclear and Medical Physics, V.N. Karazin Kharkiv National University, 4 Svobody Sq., Kharkiv 61022, Ukraine. Department of Neuroscience and Biomedical Engineering, School of Science and Technology, Aalto University, FI-00076, Espoo, Finland. Author to whom any correspondence should be addressed. 19/2 Tankopiya Str., ap. 47, Kharkov 61091, Ukraine
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90
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Kinetics of protein fibril formation: Methods and mechanisms. Int J Biol Macromol 2016; 100:3-10. [PMID: 27327908 DOI: 10.1016/j.ijbiomac.2016.06.052] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 06/14/2016] [Accepted: 06/16/2016] [Indexed: 11/23/2022]
Abstract
Amyloid fibril formation is a self-assembly reaction induced by favourable conformational changes of proteins leading to a stable, structurally organized aggregates. The deposition of stable protein fibrils in organs and tissues results in many diseases which are generally referred as amyloidosis. Though different disease conditions originate from sequentially and structurally different proteins, their fibrillar forms share common structural features. In vitro, fibril structure and kinetic pathway are investigated by using spectroscopic (fluorescence, circular dichroism, crystallography and solid state-NMR) and microscopic techniques. The kinetics of fibril formation is analysed using different mechanisms to understand the microscopic processes involved in the fibrillation reaction. This review discusses the assumptions, mechanisms, and limitations of some of the widely applied kinetic equations. Understanding of these equations would help to quantify the effect of the different microscopic process on the overall fibrillation kinetics which could aid in designing appropriate molecules to intervene in the aggregation process at different stages.
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91
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Chaturvedi SK, Khan JM, Siddiqi MK, Alam P, Khan RH. Comparative insight into surfactants mediated amyloidogenesis of lysozyme. Int J Biol Macromol 2016; 83:315-25. [DOI: 10.1016/j.ijbiomac.2015.11.053] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 11/18/2015] [Accepted: 11/19/2015] [Indexed: 12/14/2022]
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92
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Dec R, Babenko V, Dzwolak W. Molecules of Congo red caught hopping between insulin fibrils: a chiroptical probe of the dye–amyloid binding dynamics. RSC Adv 2016. [DOI: 10.1039/c6ra22067c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Binding dynamics of insulin amyloid–Congo red complex were probed through a new approach based on induced circular dichroism.
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Affiliation(s)
- Robert Dec
- Department of Chemistry
- Biological and Chemical Research Centre
- University of Warsaw
- 02-093 Warsaw
- Poland
| | - Viktoria Babenko
- Department of Chemistry
- Biological and Chemical Research Centre
- University of Warsaw
- 02-093 Warsaw
- Poland
| | - Wojciech Dzwolak
- Department of Chemistry
- Biological and Chemical Research Centre
- University of Warsaw
- 02-093 Warsaw
- Poland
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93
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Srisuk P, Correlo VM, Leonor IB, Palladino P, Reis RL. Effect of Melanomal Proteins on Sepia Melanin Assembly. J MACROMOL SCI B 2015. [DOI: 10.1080/00222348.2015.1103430] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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94
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Jagusiak A, Konieczny L, Krol M, Marszalek P, Piekarska B, Piwowar P, Roterman I, Rybarska J, Stopa B, Zemanek G. Intramolecular immunological signal hypothesis revived--structural background of signalling revealed by using Congo Red as a specific tool. Mini Rev Med Chem 2015; 14:1104-13. [PMID: 25429660 PMCID: PMC4440395 DOI: 10.2174/1389557514666141127150803] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 10/11/2014] [Accepted: 11/11/2014] [Indexed: 11/22/2022]
Abstract
Micellar structures formed by self-assembling Congo red molecules bind to proteins penetrating into functionrelated
unstable packing areas. Here, we have used Congo red - a supramolecular protein ligand to investigate how the
intramolecular structural changes that take place in antibodies following antigen binding lead to complement activation.
According to our findings, Congo red binding significantly enhances the formation of antigen-antibody complexes. As a
result, even low-affinity transiently binding antibodies can participate in immune complexes in the presence of Congo
red, although immune complexes formed by these antibodies fail to trigger the complement cascade. This indicates that
binding of antibodies to the antigen may not, by itself, fulfill the necessary conditions to generate the signal which
triggers effector activity. These findings, together with the results of molecular dynamics simulation studies, enable us to
conclude that, apart from the necessary assembling of antibodies, intramolecular structural changes generated by
strains which associate high- affinity bivalent antibody fitting to antigen determinants are also required to cross the
complement activation threshold.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - G Zemanek
- Department of Bioinformatics and Telemedicine, Jagiellonian University, Medical College, Lazarza 16, 31- 530 Krakow, Poland..
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95
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Chao CC, Huang CM, Chiang HH, Luo KR, Kan HW, Yang NCC, Chiang H, Lin WM, Lai SM, Lee MJ, Shun CT, Hsieh ST. Sudomotor innervation in transthyretin amyloid neuropathy: Pathology and functional correlates. Ann Neurol 2015; 78:272-83. [PMID: 25973863 PMCID: PMC5034810 DOI: 10.1002/ana.24438] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 04/25/2015] [Accepted: 05/10/2015] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Autonomic neuropathy is a major component of familial amyloid polyneuropathy (FAP) due to mutated transthyretin, with sudomotor failure as a common manifestation. This study aimed to investigate the pathology and clinical significance of sudomotor denervation. METHODS Skin biopsies were performed on the distal leg of FAP patients with a follow-up duration of 3.8 ± 1.6 years. Sudomotor innervation was stained with 2 markers: protein gene product 9.5 (PGP 9.5), a general neuronal marker, and vasoactive intestinal peptide (VIP), a sudomotor nerve functional marker, followed by quantitation according to sweat gland innervation index (SGII) for PGP 9.5 (SGIIPGP 9.5) and VIP (SGIIVIP). RESULTS There were 28 patients (25 men) with Ala97Ser transthyretin and late onset (59.9 ± 6.0 years) disabling neuropathy. Autonomic symptoms were present in 22 patients (78.6%) at the time of skin biopsy. The SGIIPGP 9.5 and SGIIVIP of FAP patients were significantly lower than those of age- and gender-matched controls. The reduction of SGIIVIP was more severe than that of SGIIPGP 9.5 (p = 0.002). Patients with orthostatic hypotension or absent sympathetic skin response at palms were associated with lower SGIIPGP 9.5 (p = 0.019 and 0.002, respectively). SGIIPGP 9.5 was negatively correlated with the disability grade at the time of skin biopsy (p = 0.004), and was positively correlated with the interval from the time of skin biopsy to the time of wheelchair usage (p = 0.029). INTERPRETATION This study documented the pathological evidence of sudomotor denervation in FAP. SGIIPGP 9.5 was functionally correlated with autonomic symptoms, autonomic tests, ambulation status, and progression of disability.
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Affiliation(s)
- Chi-Chao Chao
- Department of Neurology, National Taiwan University Hospital
| | - Cho-Min Huang
- Department of Anatomy and Cell Biology, National Taiwan University College of Medicine
| | - Hao-Hua Chiang
- Department of Anatomy and Cell Biology, National Taiwan University College of Medicine
| | - Kai-Ren Luo
- Department of Anatomy and Cell Biology, National Taiwan University College of Medicine
| | - Hung-Wei Kan
- Department of Anatomy and Cell Biology, National Taiwan University College of Medicine
| | - Naomi Chu-Chiao Yang
- Department of Anatomy and Cell Biology, National Taiwan University College of Medicine
| | - Hao Chiang
- Department of Anatomy and Cell Biology, National Taiwan University College of Medicine
| | - Whei-Min Lin
- Department of Anatomy and Cell Biology, National Taiwan University College of Medicine
| | - Shu-Mei Lai
- Department of Anatomy and Cell Biology, National Taiwan University College of Medicine
| | - Ming-Jen Lee
- Department of Neurology, National Taiwan University Hospital
| | - Chia-Tung Shun
- Department of Pathology, National Taiwan University Hospital
- Department of Forensic Medicine
| | - Sung-Tsang Hsieh
- Department of Neurology, National Taiwan University Hospital
- Department of Anatomy and Cell Biology, National Taiwan University College of Medicine
- Graduate Institute of Brain and Mind Sciences
- Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei, Taiwan
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Ishtikhar M, Usmani SS, Gull N, Badr G, Mahmoud MH, Khan RH. Inhibitory effect of copper nanoparticles on rosin modified surfactant induced aggregation of lysozyme. Int J Biol Macromol 2015; 78:379-88. [DOI: 10.1016/j.ijbiomac.2015.03.069] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2014] [Revised: 03/10/2015] [Accepted: 03/12/2015] [Indexed: 12/19/2022]
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97
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de Vasconcelos DN, Ximenes VF. Albumin-induced circular dichroism in Congo red: Applications for studies of amyloid-like fibril aggregates and binding sites. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 150:321-330. [PMID: 26056983 DOI: 10.1016/j.saa.2015.05.089] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Revised: 05/15/2015] [Accepted: 05/25/2015] [Indexed: 06/04/2023]
Abstract
Congo red (CR), one of the most commonly used dyes for the identification of amyloid fibril aggregates, is also a ligand of native bovine serum albumin (BSA). Induced circular dichroism (ICD) is a phenomenon observed when a chiral compound induces chirality in an achiral one. Here, we study the spectral properties and analytical applications of ICD in Congo red provoked by its interaction with BSA. The complex BSA:CR displays a strong ICD spectrum with a positive band at 412 nm and two negative bands at 356 and 490 nm. The use of site I and site II albumin ligands as warfarin and ibuprofen, respectively, provoked different alterations in the Congo red ICD spectrum. The BSA binding sites were modified by oxidation and the ICD signal was sensitive to this alteration. The thermal treatment of the BSA:CR complex (30-90 °C) was monitored by ICD at 490 nm and showed a sigmoidal pattern typical of phase transition in proteins. The altered ICD spectrum is consistent with the formation of amyloid-like fibril aggregates in BSA, which was confirmed by thioflavin T and Rayleigh scattering assays. In conclusion, the ICD provoked by the binding of Congo red to albumin may represent a new spectroscopic technique for studying alterations in the structure of albumin regarding its binding sites and the formation of amyloid aggregates.
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Affiliation(s)
- Débora Naliati de Vasconcelos
- Department of Chemistry, Faculty of Sciences, São Paulo State University (UNESP), 17033-360 Bauru, São Paulo, Brazil
| | - Valdecir Farias Ximenes
- Department of Chemistry, Faculty of Sciences, São Paulo State University (UNESP), 17033-360 Bauru, São Paulo, Brazil.
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98
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Hobley L, Harkins C, MacPhee CE, Stanley-Wall NR. Giving structure to the biofilm matrix: an overview of individual strategies and emerging common themes. FEMS Microbiol Rev 2015; 39:649-69. [PMID: 25907113 PMCID: PMC4551309 DOI: 10.1093/femsre/fuv015] [Citation(s) in RCA: 331] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/09/2015] [Indexed: 01/24/2023] Open
Abstract
Biofilms are communities of microbial cells that underpin diverse processes including sewage bioremediation, plant growth promotion, chronic infections and industrial biofouling. The cells resident in the biofilm are encased within a self-produced exopolymeric matrix that commonly comprises lipids, proteins that frequently exhibit amyloid-like properties, eDNA and exopolysaccharides. This matrix fulfils a variety of functions for the community, from providing structural rigidity and protection from the external environment to controlling gene regulation and nutrient adsorption. Critical to the development of novel strategies to control biofilm infections, or the capability to capitalize on the power of biofilm formation for industrial and biotechnological uses, is an in-depth knowledge of the biofilm matrix. This is with respect to the structure of the individual components, the nature of the interactions between the molecules and the three-dimensional spatial organization. We highlight recent advances in the understanding of the structural and functional role that carbohydrates and proteins play within the biofilm matrix to provide three-dimensional architectural integrity and functionality to the biofilm community. We highlight, where relevant, experimental techniques that are allowing the boundaries of our understanding of the biofilm matrix to be extended using Escherichia coli, Staphylococcus aureus, Vibrio cholerae, and Bacillus subtilis as exemplars. Examining the structure and function of the biofilm extracellular matrix.
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Affiliation(s)
- Laura Hobley
- Division of Molecular Microbiology, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Catriona Harkins
- Division of Molecular Microbiology, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Cait E MacPhee
- James Clerk Maxwell Building, School of Physics, University of Edinburgh, Edinburgh EH9 3JZ, UK
| | - Nicola R Stanley-Wall
- Division of Molecular Microbiology, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
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99
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Viet MH, Siposova K, Bednarikova Z, Antosova A, Nguyen TT, Gazova Z, Li MS. In Silico and in Vitro Study of Binding Affinity of Tripeptides to Amyloid β Fibrils: Implications for Alzheimer’s Disease. J Phys Chem B 2015; 119:5145-55. [DOI: 10.1021/acs.jpcb.5b00006] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Man Hoang Viet
- Institute
of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw, Poland
| | - Katarina Siposova
- Department
of Biophysics, Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, 040 01 Kosice, Slovakia
- Department
of Biochemistry, Institute of Chemistry, Faculty of Science, P. J. Safarik University, Srobarova 2, 041
54 Kosice, Slovakia
| | - Zuzana Bednarikova
- Department
of Biophysics, Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, 040 01 Kosice, Slovakia
- Department
of Biochemistry, Institute of Chemistry, Faculty of Science, P. J. Safarik University, Srobarova 2, 041
54 Kosice, Slovakia
| | - Andrea Antosova
- Department
of Biophysics, Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, 040 01 Kosice, Slovakia
- Department
of Biochemistry, Institute of Chemistry, Faculty of Science, P. J. Safarik University, Srobarova 2, 041
54 Kosice, Slovakia
| | - Truc Trang Nguyen
- Institute for Computational Science and Technology, Quang Trung Software City, Tan Chanh Hiep Ward,
District 12, Ho Chi Minh City, Vietnam
| | - Zuzana Gazova
- Department
of Biophysics, Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, 040 01 Kosice, Slovakia
| | - Mai Suan Li
- Institute
of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw, Poland
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100
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Young LM, Saunders JC, Mahood RA, Revill CH, Foster RJ, Tu LH, Raleigh DP, Radford SE, Ashcroft AE. Screening and classifying small-molecule inhibitors of amyloid formation using ion mobility spectrometry-mass spectrometry. Nat Chem 2014; 7:73-81. [PMID: 25515893 PMCID: PMC4280571 DOI: 10.1038/nchem.2129] [Citation(s) in RCA: 223] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Accepted: 11/05/2014] [Indexed: 12/28/2022]
Abstract
The search for therapeutic agents which bind specifically to precursor protein conformations and inhibit amyloid assembly is an important challenge. Identifying such inhibitors is difficult since many protein precursors of aggregation are partially folded or intrinsically disordered, ruling out structure-based design. Furthermore, inhibitors can act by a variety of mechanisms, including specific or non-specific binding, as well as colloidal inhibition. Here we report a high throughput method based on ion mobility spectrometry-mass spectrometry (IMS-MS) that is capable of rapidly detecting small molecules that bind to amyloid precursors, identifying the interacting protein species, and defining the mode of inhibition. Using this method we have classified a variety of small molecules that are potential inhibitors of human islet amyloid polypeptide (hIAPP) aggregation or amyloid-beta 1-40 (Aβ40) aggregation as either specific, non-specific, colloidal or non-interacting. We also demonstrate the ability of IMS-MS to screen for inhibitory small molecules in a 96-well plate format and use this to discover a new inhibitor of hIAPP amyloid assembly.
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Affiliation(s)
- Lydia M Young
- Astbury Centre for Structural Molecular Biology, University of Leeds, LS2 9JT, UK.,School of Molecular and Cellular Biology, University of Leeds, LS2 9JT, UK
| | - Janet C Saunders
- Astbury Centre for Structural Molecular Biology, University of Leeds, LS2 9JT, UK.,School of Molecular and Cellular Biology, University of Leeds, LS2 9JT, UK
| | - Rachel A Mahood
- Astbury Centre for Structural Molecular Biology, University of Leeds, LS2 9JT, UK.,School of Molecular and Cellular Biology, University of Leeds, LS2 9JT, UK
| | - Charlotte H Revill
- Astbury Centre for Structural Molecular Biology, University of Leeds, LS2 9JT, UK.,School of Chemistry, University of Leeds, LS2 9JT, UK
| | - Richard J Foster
- Astbury Centre for Structural Molecular Biology, University of Leeds, LS2 9JT, UK.,School of Chemistry, University of Leeds, LS2 9JT, UK
| | - Ling-Hsien Tu
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794-3400, USA
| | - Daniel P Raleigh
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794-3400, USA
| | - Sheena E Radford
- Astbury Centre for Structural Molecular Biology, University of Leeds, LS2 9JT, UK.,School of Molecular and Cellular Biology, University of Leeds, LS2 9JT, UK
| | - Alison E Ashcroft
- Astbury Centre for Structural Molecular Biology, University of Leeds, LS2 9JT, UK.,School of Molecular and Cellular Biology, University of Leeds, LS2 9JT, UK
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