1
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Melnikova D, Ranjan VV, Nesmelov YE, Skirda VD, Nesmelova IV. Translational Diffusion and Self-Association of an Intrinsically Disordered Protein κ-Casein Using NMR with Ultra-High Pulsed-Field Gradient and Time-Resolved FRET. J Phys Chem B 2024; 128:7781-7791. [PMID: 39106061 PMCID: PMC11331516 DOI: 10.1021/acs.jpcb.4c03625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2024] [Revised: 07/09/2024] [Accepted: 07/17/2024] [Indexed: 08/07/2024]
Abstract
Much attention has been given to studying the translational diffusion of globular proteins, whereas the translational diffusion of intrinsically disordered proteins (IDPs) is less studied. In this study, we investigate the translational diffusion and how it is affected by the self-association of an IDP, κ-casein, using pulsed-field gradient nuclear magnetic resonance and time-resolved Förster resonance energy transfer. Using the analysis of the shape of diffusion attenuation and the concentration dependence of κ-casein diffusion coefficients and intermolecular interactions, we demonstrate that κ-casein exhibits continuous self-association. When the volume fraction of κ-casein is below 0.08, we observe that κ-casein self-association results in a macroscopic phase separation upon storage at 4 °C. At κ-casein volume fractions above 0.08, self-association leads to the formation of labile gel-like networks without subsequent macroscopic phase separation. Unlike α-casein, which shows a strong concentration dependence and extensive gel-like network formation, only one-third of κ-casein molecules participate in the gel network at a time, resulting in a more dynamic and less extensive structure. These findings highlight the unique association properties of κ-casein, contributing to a better understanding of its behavior under various conditions and its potential role in casein micelle formation.
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Affiliation(s)
- Daria
L. Melnikova
- Department
of Physics of Molecular Systems, Kazan Federal
University, Kazan 420011, Russia
| | - Venkatesh V. Ranjan
- Department
of Chemistry, University of North Carolina, Charlotte, North Carolina 28223, United States
- Department
of Physics and Optical Sciences, University
of North Carolina, Charlotte, North Carolina 28223, United States
| | - Yuri E. Nesmelov
- Department
of Physics and Optical Sciences, University
of North Carolina, Charlotte, North Carolina 28223, United States
| | - Vladimir D. Skirda
- Department
of Physics of Molecular Systems, Kazan Federal
University, Kazan 420011, Russia
| | - Irina V. Nesmelova
- Department
of Physics and Optical Sciences, University
of North Carolina, Charlotte, North Carolina 28223, United States
- School
of Data Science, University of North Carolina, Charlotte, North Carolina 28223, United States
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2
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Holt C, Carver JA. Invited review: Modeling milk stability. J Dairy Sci 2024; 107:5259-5279. [PMID: 38522835 DOI: 10.3168/jds.2024-24779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Accepted: 02/15/2024] [Indexed: 03/26/2024]
Abstract
Novel insights into the stability of milk and milk products during storage and processing result from describing caseins near neutral pH as hydrophilic, intrinsically disordered, proteins. Casein solubility is strongly influenced by pH and multivalent ion binding. Solubility is high at a neutral pH or above, but decreases as the casein net charge approaches zero, allowing a condensed casein phase or gel to form, then increases at lower pH. Of particular importance for casein micelle stability near neutral pH is the proportion of free caseins in the micelle (i.e., caseins not bound directly to nanoclusters of calcium phosphate). Free caseins are more soluble and better able to act as molecular chaperones (to prevent casein and whey protein aggregation) than bound caseins. Some free caseins are highly phosphorylated and can also act as mineral chaperones to inhibit the growth of calcium phosphate phases and prevent mineralized deposits from forming on membranes or heat exchangers. Thus, casein micelle stability is reduced when free caseins bind to amyloid fibrils, destabilized whey proteins or calcium phosphate. The multivalent-binding model of the casein micelle quantitatively describes these and other factors affecting the stability of milk and milk protein products during manufacture and storage.
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Affiliation(s)
- C Holt
- School of Biomolecular Sciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom.
| | - J A Carver
- Research School of Chemistry, The Australian National University, Acton, ACT 2601, Australia
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3
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Raynes JK, Mata J, Wilde KL, Carver JA, Kelly SM, Holt C. Structure of biomimetic casein micelles: Critical tests of the hydrophobic colloid and multivalent-binding models using recombinant deuterated and phosphorylated β-casein. J Struct Biol X 2024; 9:100096. [PMID: 38318529 PMCID: PMC10840362 DOI: 10.1016/j.yjsbx.2024.100096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 01/08/2024] [Accepted: 01/17/2024] [Indexed: 02/07/2024] Open
Abstract
Milk contains high concentrations of amyloidogenic casein proteins and is supersaturated with respect to crystalline calcium phosphates such as apatite. Nevertheless, the mammary gland normally remains unmineralized and free of amyloid. Unlike κ-casein, β- and αS-caseins are highly effective mineral chaperones that prevent ectopic and pathological calcification of the mammary gland. Milk invariably contains a mixture of two to five different caseins that act on each other as molecular chaperones. Instead of forming amyloid fibrils, several thousand caseins and hundreds of nanoclusters of amorphous calcium phosphate combine to form fuzzy complexes called casein micelles. To understand the biological functions of the casein micelle its structure needs to be understood better than at present. The location in micelles of the highly amyloidogenic κ-casein is disputed. In traditional hydrophobic colloid models, it, alone, forms a stabilizing surface coat that also determines the average size of the micelles. In the recent multivalent-binding model, κ-casein is present throughout the micelle, in intimate contact with the other caseins. To discriminate between these models, a range of biomimetic micelles was prepared using a fixed concentration of the mineral chaperone β-casein and nanoclusters of calcium phosphate, with variable concentrations of κ-casein. A biomimetic micelle was also prepared using a highly deuterated and in vivo phosphorylated recombinant β-casein with calcium phosphate and unlabelled κ-casein. Neutron and X-ray scattering experiments revealed that κ-casein is distributed throughout the micelle, in quantitative agreement with the multivalent-binding model but contrary to the hydrophobic colloid models.
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Affiliation(s)
- Jared K. Raynes
- CSIRO Agriculture & Food, 671 Sneydes Road, Werribee, VIC 3031, Australia
- All G Foods, Waterloo, NSW 2006, Australia
| | - Jitendra Mata
- Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW 2234, Australia
- School of Chemistry, University of New South Wales, Sydney 2052, Australia
| | - Karyn L. Wilde
- National Deuteration Facility, Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW 2234, Australia
| | - John A. Carver
- Research School of Chemistry, The Australian National University, Acton, ACT 2601, Australia
| | - Sharon M. Kelly
- School of Molecular Biosciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Carl Holt
- School of Molecular Biosciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom
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4
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Zhang H, Lv S, Jin C, Ren F, Wang J. Wheat gluten amyloid fibrils: Conditions, mechanism, characterization, application, and future perspectives. Int J Biol Macromol 2023; 253:126435. [PMID: 37611682 DOI: 10.1016/j.ijbiomac.2023.126435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 08/17/2023] [Accepted: 08/18/2023] [Indexed: 08/25/2023]
Abstract
Amyloid fibrils have excellent structural characteristics, such as a high aspect ratio, excellent stiffness, and a wide availability of functional groups on the surface. More studies are now focusing on the formation of amyloid fibrils using food proteins. Protein fibrillation is now becoming recognized as a promising strategy for enhancing the function of food proteins and expanding their range of applications. Wheat gluten is rich in glutamine (Q), hydrophobic amino acids, and the α-helix structure with high β-sheet tendency. These characteristics make it very easy for wheat gluten to form amyloid fibrils. The conditions, formation mechanism, characterization methods, and application of amyloid fibrils formed by wheat gluten are summarized in this review. Further exploration of amyloid fibrils formed by wheat gluten will reveal how they can play a significant role in food, biology, and other fields, especially in medicine.
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Affiliation(s)
- Huijuan Zhang
- School of Food and Health, Beijing Technology & Business University (BTBU), Beijing 100048, China.
| | - Shihao Lv
- School of Food and Health, Beijing Technology & Business University (BTBU), Beijing 100048, China
| | - Chengming Jin
- School of Food and Health, Beijing Technology & Business University (BTBU), Beijing 100048, China
| | - Feiyue Ren
- School of Food and Health, Beijing Technology & Business University (BTBU), Beijing 100048, China
| | - Jing Wang
- School of Food and Health, Beijing Technology & Business University (BTBU), Beijing 100048, China.
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5
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Milyaeva OY, Akentiev AV, Bykov AG, Loglio G, Miller R, Portnaya I, Rafikova AR, Noskov BA. Dynamic Properties of Adsorption Layers of κ-Casein Fibrils. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:15268-15274. [PMID: 37867296 DOI: 10.1021/acs.langmuir.3c01950] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2023]
Abstract
The dynamic surface properties of native κ-casein solutions and aqueous dispersions of its fibrils differ significantly from the corresponding properties of the systems with globular proteins. The dependence of the dynamic surface elasticity of κ-casein solutions on surface pressure has a local maximum, indicating partial displacement of macromolecules from the proximal region of the surface layer to the distal one. This dependence becomes monotonic for fibril dispersions, similar to the results for dispersions of globular protein fibrils, but unlike the latter case, the surface elasticity close to the steady state reaches values that are approximately four times higher than the data for native protein solutions at the same concentrations.
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Affiliation(s)
- Olga Yu Milyaeva
- Department of Colloid Chemistry, St. Petersburg State University, Universitetsky pr. 26, 198504 St. Petersburg, Russia
| | - Alexander V Akentiev
- Department of Colloid Chemistry, St. Petersburg State University, Universitetsky pr. 26, 198504 St. Petersburg, Russia
| | - Alexey G Bykov
- Department of Colloid Chemistry, St. Petersburg State University, Universitetsky pr. 26, 198504 St. Petersburg, Russia
| | - Giuseppe Loglio
- Institute of Condensed Matter Chemistry and Energy Technology, 16149 Genova, Italy
| | - Reinhard Miller
- Institute of Condensed Matter Physics, Technische Universität Darmstadt, D-64289 Darmstadt, Germany
| | - Irina Portnaya
- CryoEM Laboratory of Soft Matter, Faculty of Biotechnology and Food Engineering, Technion - Israel Institute of Technology, Haifa 32000003, Israel
| | - Anastasiya R Rafikova
- Department of Colloid Chemistry, St. Petersburg State University, Universitetsky pr. 26, 198504 St. Petersburg, Russia
| | - Boris A Noskov
- Department of Colloid Chemistry, St. Petersburg State University, Universitetsky pr. 26, 198504 St. Petersburg, Russia
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6
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Kumar M, Teakel SL, Swarbrick C, Chowdhury IS, Thorn DC, Sunde M, Carver JA, Forwood JK. Amyloid fibril formation, structure and domain swapping of acyl-coenzyme A thioesterase-7. FEBS J 2023; 290:4057-4073. [PMID: 37042241 DOI: 10.1111/febs.16795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 02/23/2023] [Accepted: 04/11/2023] [Indexed: 04/13/2023]
Abstract
Acyl-coenzyme A thioesterase (Acot) enzymes are involved in a broad range of essential intracellular roles including cell signalling, lipid metabolism, inflammation and the opening of ion channels. Dysregulation in lipid metabolism has been linked to neuroinflammatory and neurological disorders such as Alzheimer's and Parkinson's diseases. Structurally, Acot enzymes adopt a circularised trimeric arrangement with each monomer containing an N- and a C-terminal hotdog domain. Acot7 spontaneously forms amyloid fibrils in vitro under physiological conditions. The resultant amyloid fibrillar structures were characterised by dye-binding fluorescence assays, far-UV circular dichroism spectroscopy, transmission electron microscopy and X-ray fibre diffraction. Acot7 has an unusual mechanism of aggregation with no lag phase. The initial phase (~ 18 h) of aggregation involves conformational rearrangement within the oligomers to form species of enhanced β-sheet character. The subsequent loss of α-helical structure is accompanied by large-scale amyloid fibril formation. The crystal structure of Acot7 revealed an unexpected arrangement of the two domains within the circularised trimeric structure, which is the basis for a proposed mechanism of amyloid fibril formation involving domain swapping during the initial phase of aggregation. Acot7 formed fibrils in the presence of its substrate arachidonoyl-CoA and its inhibitors and maintained its enzyme activity during fibril assembly. It is proposed that the Acot7 fibrillar form acts as functional amyloid.
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Affiliation(s)
- Manjeet Kumar
- Research School of Chemistry, The Australian National University, Acton, Australia
| | - Sarah L Teakel
- School of Dentistry and Medical Science, Charles Sturt University, Wagga Wagga, Australia
| | - Crystall Swarbrick
- School of Dentistry and Medical Science, Charles Sturt University, Wagga Wagga, Australia
| | - Intifar S Chowdhury
- Research School of Chemistry, The Australian National University, Acton, Australia
| | - David C Thorn
- Research School of Chemistry, The Australian National University, Acton, Australia
| | - Margaret Sunde
- School of Medical Sciences, The University of Sydney, Australia
| | - John A Carver
- Research School of Chemistry, The Australian National University, Acton, Australia
| | - Jade K Forwood
- School of Dentistry and Medical Science, Charles Sturt University, Wagga Wagga, Australia
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7
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Mahdipour R, Ebrahimzadeh-Bideskan A, Hosseini M, Shahba S, Lombardi G, Malvandi AM, Mohammadipour A. The benefits of grape seed extract in neurological disorders and brain aging. Nutr Neurosci 2023; 26:369-383. [PMID: 35343876 DOI: 10.1080/1028415x.2022.2051954] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Common neurological disorders, including neurodegenerative diseases, stroke, epilepsy, autism and psychiatric disorders, affect many people worldwide and threaten their lives and health by inducing movement disorders, behavioral disorders, or a combination of both. Oxidative stress and neuroinflammation play a central role in neuronal damage and neurological diseases induction and progression. In addition, protein homeostasis (proteostasis) impairment occurs in many neurodegenerative diseases, which plays a critical role in the progression of the pathology. Grape seed contains several flavonoids and non-flavonoids and exerts potent antioxidant and anti-inflammatory effects. In addition, polyphenols and flavanols can maintain cellular proteostasis. Since impaired proteostasis is closely involved in all amyloid diseases, particularly neurodegenerative diseases, grape seeds extract can be a valuable therapeutic agent. Therefore, this review discusses the protective and therapeutic mechanisms of grape seed against neurological disorders and, in the end, links GSE to microRNAs as future therapeutic developments.
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Affiliation(s)
- Ramin Mahdipour
- Department of Anatomy and Cell Biology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Alireza Ebrahimzadeh-Bideskan
- Department of Anatomy and Cell Biology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
- Applied Biomedical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mahmoud Hosseini
- Applied Biomedical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- Division of Neurocognitive Sciences, Psychiatry and Behavioral Sciences Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- Neuroscience Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Sara Shahba
- Medical Biotechnology Research Center, School of Paramedicine, Guilan University of Medical Sciences, Rasht, Iran
| | - Giovanni Lombardi
- Laboratory of Experimental Biochemistry & Molecular Biology, IRCCS Istituto Ortopedico Galeazzi, Milano, Italy
- Department of Athletics, Strength and Conditioning, Poznań University of Physical Education, Poznań, Poland
| | - Amir Mohammad Malvandi
- Laboratory of Experimental Biochemistry & Molecular Biology, IRCCS Istituto Ortopedico Galeazzi, Milano, Italy
| | - Abbas Mohammadipour
- Department of Anatomy and Cell Biology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
- Applied Biomedical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
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8
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Murakami T, Kaku T, Tsukakoshi K, Iwaide S, Itoh Y, Hisada M, Nomura K, Kubo R, Ikebukuro K, Sassa-O'Brien Y, Kametani F. Identification of novel amyloidosis in dogs: α-S1-casein acquires amyloidogenicity in mammary tumor by overexpression and N-terminal truncation. Vet Pathol 2023; 60:203-213. [PMID: 36680468 DOI: 10.1177/03009858221148511] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Mammary tumor-associated amyloidosis (MTAA) in dogs is characterized by amyloid deposition in the stroma of mammary adenoma or carcinoma; however, the amyloid precursor protein remains unknown. We attempted to identify an amyloid precursor protein and elucidated its etiology by characterizing 5 cases of canine MTAA. Proteomic analyses of amyloid extracts from formalin-fixed paraffin-embedded specimens revealed α-S1-casein (CASA1) as a prime candidate and showed the N-terminal truncation of canine CASA1. Both immunohistochemistry and immunoelectron microscopy showed that amyloid deposits or fibrils in MTAA cases were positive for CASA1. Reverse transcription-polymerase chain reaction and quantitative polymerase chain reaction revealed the complete mRNA sequence encoding CASA1, whose expression was significantly higher in the amyloid-positive group. The recombinant protein of the N-terminal-truncated canine CASA1 and the synthetic peptides derived from canine and human CASA1 formed amyloid-like fibrils in vitro. Structural prediction suggested that the N-terminal region of CASA1 was disordered. Previously, full-length CASA1 was reported to inhibit the amyloidogenesis of other proteins; however, we demonstrated that CASA1 acquires amyloidogenicity via excessive synthesis followed by truncation of its disordered N-terminal region. By identifying a novel in vivo amyloidogenic protein in animals and revealing key mechanistic details of its associated pathology, this study provides valuable insights into the integrated understanding of related proteopathies.
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Affiliation(s)
- Tomoaki Murakami
- Tokyo University of Agriculture and Technology, Fuchu-shi, Japan
| | - Toshisuke Kaku
- Tokyo University of Agriculture and Technology, Koganei-shi, Japan
| | - Kaori Tsukakoshi
- Tokyo University of Agriculture and Technology, Koganei-shi, Japan
| | - Susumu Iwaide
- Tokyo University of Agriculture and Technology, Fuchu-shi, Japan
| | - Yoshiyuki Itoh
- Tokyo University of Agriculture and Technology, Fuchu-shi, Japan
| | - Miki Hisada
- Tokyo University of Agriculture and Technology, Fuchu-shi, Japan
| | | | - Rikako Kubo
- Tokyo University of Agriculture and Technology, Koganei-shi, Japan
| | | | | | - Fuyuki Kametani
- Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
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9
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Wilson MR, Satapathy S, Vendruscolo M. Extracellular protein homeostasis in neurodegenerative diseases. Nat Rev Neurol 2023; 19:235-245. [PMID: 36828943 DOI: 10.1038/s41582-023-00786-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/02/2023] [Indexed: 02/26/2023]
Abstract
The protein homeostasis (proteostasis) system encompasses the cellular processes that regulate protein synthesis, folding, concentration, trafficking and degradation. In the case of intracellular proteostasis, the identity and nature of these processes have been extensively studied and are relatively well known. By contrast, the mechanisms of extracellular proteostasis are yet to be fully elucidated, although evidence is accumulating that their age-related progressive impairment might contribute to neuronal death in neurodegenerative diseases. Constitutively secreted extracellular chaperones are emerging as key players in processes that operate to protect neurons and other brain cells by neutralizing the toxicity of extracellular protein aggregates and promoting their safe clearance and disposal. Growing evidence indicates that these extracellular chaperones exert multiple effects to promote cell viability and protect neurons against pathologies arising from the misfolding and aggregation of proteins in the synaptic space and interstitial fluid. In this Review, we outline the current knowledge of the mechanisms of extracellular proteostasis linked to neurodegenerative diseases, and we examine the latest understanding of key molecules and processes that protect the brain from the pathological consequences of extracellular protein aggregation and proteotoxicity. Finally, we contemplate possible therapeutic opportunities for neurodegenerative diseases on the basis of this emerging knowledge.
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Affiliation(s)
- Mark R Wilson
- School of Chemistry and Molecular Bioscience, Molecular Horizons Research Institute, University of Wollongong, Wollongong, New South Wales, Australia.
| | - Sandeep Satapathy
- Blavatnik Institute of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Michele Vendruscolo
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
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10
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Hewa Nadugala B, Hantink R, Nebl T, White J, Pagel CN, Ranadheera C, Logan A, Raynes JK. The role of glycosylation in amyloid fibril formation of bovine κ-casein. Curr Res Food Sci 2023; 6:100433. [PMID: 36660302 PMCID: PMC9842538 DOI: 10.1016/j.crfs.2023.100433] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 12/08/2022] [Accepted: 01/02/2023] [Indexed: 01/05/2023] Open
Abstract
In order to explore the functions of glycosylation of κ-Casein (κ-CN) in bovine milk, unglycosylated (UG) and twice glycosylated (2G) forms of κ-CN B were purified by selective precipitation followed by anion exchange chromatography from κ-CN BB milk and tested for their amyloid fibril formation and morphology, oligomerisation states and protein structure. The diameter of self-assembled κ-CN B aggregates of both glyco-form were shown for the first time to be in the same 26.0-28.7 nm range for a 1 mg mL-1 solution. The presence of two bound glycans in the protein structure of 2G κ-CN B led to a greater increase in the maximum amyloid fibril formation rate with increasing protein concentration and a difference in both length (82.0 ± 29.9 vs 50.3 ± 13.7 nm) and width (8.6 ± 2.1 vs 13.9 ± 2.5 nm) for fibril morphology compared to UG κ-CN B. The present results suggest that amyloid fibril formation proceeds at a slow but steady rate via the self-assembly of dissociated, monomeric κ-CN B proteins at concentrations of 0.22-0.44 mg mL-1. However amyloid fibril formation proceeds more rapidly via the assembly of either aggregated κ-CN present in a micelle-like form or dissociated monomeric κ-CN, packed into reorganised formational structures above the critical micellar concentration to form fibrils of differing width. The degree of glycosylation has no effect on the polarity of the adjacent environment, nor non-covalent and disulphide interactions between protein molecules when in the native form. Yet glycosylation can influence protein folding patterns of κ-CN B leading to a reduced tryptophan intrinsic fluorescence intensity for 2G compared to UG κ-CN B. These results demonstrate that glycosylation plays an important role in the modulation of aggregation states of κ-CN and contributes to a better understanding of the role of glycosylation in the formation of amyloid fibrils from intrinsically disordered proteins.
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Affiliation(s)
- Barana Hewa Nadugala
- School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, University of Melbourne, VIC, 3052, Australia,CSIRO Agriculture and Food, Werribee Victoria, 3030, Australia
| | - Rick Hantink
- CSIRO Agriculture and Food, Werribee Victoria, 3030, Australia
| | - Tom Nebl
- Biology Group, Biomedical Manufacturing Program, CSIRO, Bayview Ave/Research Way, Clayton, VIC, 3168, Australia
| | - Jacinta White
- CSIRO Manufacturing, Bayview Avenue, Clayton, VIC, 3168, Australia
| | - Charles N. Pagel
- Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC, 3052, Australia
| | - C.S. Ranadheera
- School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, University of Melbourne, VIC, 3052, Australia,Corresponding author.
| | - Amy Logan
- CSIRO Agriculture and Food, Werribee Victoria, 3030, Australia,Corresponding author.
| | - Jared K. Raynes
- School of Chemical and Biomolecular Engineering, Faculty of Engineering, The University of Sydney, NSW, 2006, Australia
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11
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Mohammad-Beigi H, Wijaya W, Madsen M, Hayashi Y, Li R, Maria Rovers TA, Jæger TC, Buell AK, Hougaard AB, Kirkensgaard JJ, Westh P, Ipsen R, Svensson B. Association of caseins with β-lactoglobulin influenced by temperature and calcium ions: A multi-parameter analysis. Food Hydrocoll 2022. [DOI: 10.1016/j.foodhyd.2022.108373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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12
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Alraawi Z, Banerjee N, Mohanty S, Kumar TKS. Amyloidogenesis: What Do We Know So Far? Int J Mol Sci 2022; 23:ijms232213970. [PMID: 36430450 PMCID: PMC9695042 DOI: 10.3390/ijms232213970] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 11/01/2022] [Accepted: 11/08/2022] [Indexed: 11/16/2022] Open
Abstract
The study of protein aggregation, and amyloidosis in particular, has gained considerable interest in recent times. Several neurodegenerative diseases, such as Alzheimer's (AD) and Parkinson's (PD) show a characteristic buildup of proteinaceous aggregates in several organs, especially the brain. Despite the enormous upsurge in research articles in this arena, it would not be incorrect to say that we still lack a crystal-clear idea surrounding these notorious aggregates. In this review, we attempt to present a holistic picture on protein aggregation and amyloids in particular. Using a chronological order of discoveries, we present the case of amyloids right from the onset of their discovery, various biophysical techniques, including analysis of the structure, the mechanisms and kinetics of the formation of amyloids. We have discussed important questions on whether aggregation and amyloidosis are restricted to a subset of specific proteins or more broadly influenced by the biophysiochemical and cellular environment. The therapeutic strategies and the significant failure rate of drugs in clinical trials pertaining to these neurodegenerative diseases have been also discussed at length. At a time when the COVID-19 pandemic has hit the globe hard, the review also discusses the plausibility of the far-reaching consequences posed by the virus, such as triggering early onset of amyloidosis. Finally, the application(s) of amyloids as useful biomaterials has also been discussed briefly in this review.
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Affiliation(s)
- Zeina Alraawi
- Department of Chemistry and Biochemistry, Fulbright College of Art and Science, University of Arkansas, Fayetteville, AR 72701, USA
| | - Nayan Banerjee
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Srujana Mohanty
- Department of Chemical Sciences, Indian Institute of Science Education and Research, Kolkata 741246, India
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13
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Sedov I, Khaibrakhmanova D. Molecular Mechanisms of Inhibition of Protein Amyloid Fibril Formation: Evidence and Perspectives Based on Kinetic Models. Int J Mol Sci 2022; 23:13428. [PMID: 36362217 PMCID: PMC9657184 DOI: 10.3390/ijms232113428] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 10/29/2022] [Accepted: 10/31/2022] [Indexed: 11/06/2022] Open
Abstract
Inhibition of fibril formation is considered a possible treatment strategy for amyloid-related diseases. Understanding the molecular nature of inhibitor action is crucial for the design of drug candidates. In the present review, we describe the common kinetic models of fibril formation and classify known inhibitors by the mechanism of their interactions with the aggregating protein and its oligomers. This mechanism determines the step or steps of the aggregation process that become inhibited and the observed changes in kinetics and equilibrium of fibril formation. The results of numerous studies indicate that possible approaches to antiamyloid inhibitor discovery include the search for the strong binders of protein monomers, cappers blocking the ends of the growing fibril, or the species absorbing on the surface of oligomers preventing nucleation. Strongly binding inhibitors stabilizing the native state can be promising for the structured proteins while designing the drug candidates targeting disordered proteins is challenging.
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Affiliation(s)
- Igor Sedov
- Chemical Institute, Kazan Federal University, Kremlevskaya 18, 420008 Kazan, Russia
- Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Center of RAS, 420111 Kazan, Russia
- Sirius University of Science and Technology, 1 Olympic Ave, 354340 Sochi, Russia
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14
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Bahraminejad E, Paliwal D, Sunde M, Holt C, Carver JA, Thorn DC. Amyloid fibril formation by α S1- and β-casein implies that fibril formation is a general property of casein proteins. BIOCHIMICA ET BIOPHYSICA ACTA. PROTEINS AND PROTEOMICS 2022; 1870:140854. [PMID: 36087849 DOI: 10.1016/j.bbapap.2022.140854] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 08/31/2022] [Accepted: 09/02/2022] [Indexed: 06/15/2023]
Abstract
Caseins are a diverse family of intrinsically disordered proteins present in the milks of all mammals. A property common to two cow paralogues, αS2- and κ-casein, is their propensity in vitro to form amyloid fibrils, the highly ordered protein aggregates associated with many age-related, including neurological, diseases. In this study, we explored whether amyloid fibril-forming propensity is a general feature of casein proteins by examining the other cow caseins (αS1 and β) as well as β-caseins from camel and goat. Small-angle X-ray scattering measurements indicated that cow αS1- and β-casein formed large spherical aggregates at neutral pH and 20°C. Upon incubation at 65°C, αS1- and β-casein underwent conversion to amyloid fibrils over the course of ten days, as shown by thioflavin T binding, transmission electron microscopy, and X-ray fibre diffraction. At the lower temperature of 37°C where fibril formation was more limited, camel β-casein exhibited a greater fibril-forming propensity than its cow or goat orthologues. Limited proteolysis of cow and camel β-casein fibrils and analysis by mass spectrometry indicated a common amyloidogenic sequence in the proline, glutamine-rich, C-terminal region of β-casein. These findings highlight the persistence of amyloidogenic sequences within caseins, which likely contribute to their functional, heterotypic self-assembly; in all mammalian milks, at least two caseins coalesce to form casein micelles, implying that caseins diversified partly to avoid dysfunctional amyloid fibril formation.
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Affiliation(s)
- Elmira Bahraminejad
- Research School of Chemistry, The Australian National University, Acton, ACT 2601, Australia
| | - Devashi Paliwal
- Research School of Chemistry, The Australian National University, Acton, ACT 2601, Australia
| | - Margaret Sunde
- School of Medical Sciences, Faculty of Medicine and Health, and Sydney Nano, The University of Sydney, Sydney, NSW 2006, Australia
| | - Carl Holt
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - John A Carver
- Research School of Chemistry, The Australian National University, Acton, ACT 2601, Australia
| | - David C Thorn
- Research School of Chemistry, The Australian National University, Acton, ACT 2601, Australia.
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15
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Membrane cholesterol modulates the dynamics and depth of penetration of κ-casein. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.119849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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16
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Daniloski D, McCarthy NA, Huppertz T, Vasiljevic T. What is the impact of amino acid mutations in the primary structure of caseins on the composition and functionality of milk and dairy products? Curr Res Food Sci 2022; 5:1701-1712. [PMID: 36212081 PMCID: PMC9535159 DOI: 10.1016/j.crfs.2022.09.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 09/25/2022] [Accepted: 09/28/2022] [Indexed: 11/19/2022] Open
Abstract
The impact of amino acid mutations within the peptide structure of bovine milk protein is important to understand as it can effect processability and subsequently effect its physiological properties. Genetic polymorphisms of bovine caseins can influence the chemical, structural, and technological properties, including casein micelle morphology, calcium distribution, network creation upon gelation, and surface activity. The A1 and A2 genetic variants of β-casein have recently acquired growing attention from both academia and industry, prompting new developments in the area. The difference between these two genetic variants is the inclusion of either proline in β-casein A2 or histidine in β-casein A1 at position 67 in the peptide chain. The aim of this review was to examine the extent to which milk and ingredient functionality is influenced by β-casein phenotype. One of the main findings of this review was although β-casein A1 was found to be the dominant variant in milks with superior acid gelation and rennet coagulation properties, milks comprised of β-casein A2 possessed greater emulsion and foam formation capabilities. The difference in the casein micelle assembly, hydrophobicity, and chaperone activity of caseins may explain the contrast in the functionality of milks containing β-casein from either A1 or A2 families. This review provides new insights into the subtle variations in the physicochemical properties of bovine milks, which could potentially support dairy producers in the development of new dairy products with different functional properties. Impact of β- and other caseins on the casein micelle structure and functionality. Proline and histidine in β-caseins play a key role in casein micelle conformation. Chaperone activity of β-casein A2 towards heat-induced aggregation of whey protein. Gels prepared of milks with β-casein A1 possess a denser and firmer structure. Ordered structure of β-casein A2 led to improved emulsion and foam formation.
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Affiliation(s)
- Davor Daniloski
- Advanced Food Systems Research Unit, Institute for Sustainable Industries and Liveable Cities and College of Health and Biomedicine, Victoria University, Melbourne, VIC, 8001, Australia
- Food Chemistry and Technology Department, Teagasc Food Research Centre, Moorepark, Fermoy, P61 C996, Cork, Ireland
| | - Noel A. McCarthy
- Food Chemistry and Technology Department, Teagasc Food Research Centre, Moorepark, Fermoy, P61 C996, Cork, Ireland
| | - Thom Huppertz
- Advanced Food Systems Research Unit, Institute for Sustainable Industries and Liveable Cities and College of Health and Biomedicine, Victoria University, Melbourne, VIC, 8001, Australia
- FrieslandCampina, Amersfoort, the Netherlands
- Wageningen University & Research, Wageningen, the Netherlands
| | - Todor Vasiljevic
- Advanced Food Systems Research Unit, Institute for Sustainable Industries and Liveable Cities and College of Health and Biomedicine, Victoria University, Melbourne, VIC, 8001, Australia
- Corresponding author.
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Horvath A, Fuxreiter M, Vendruscolo M, Holt C, Carver JA. Are casein micelles extracellular condensates formed by liquid-liquid phase separation? FEBS Lett 2022; 596:2072-2085. [PMID: 35815989 DOI: 10.1002/1873-3468.14449] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 06/27/2022] [Indexed: 11/05/2022]
Abstract
Casein micelles are extracellular polydisperse assemblies of unstructured casein proteins. Caseins are the major component of milk. Within casein micelles, casein molecules are stabilised by binding to calcium phosphate nanoclusters and, by acting as molecular chaperones, through multivalent interactions. In light of such interactions, we discuss whether casein micelles can be considered as extracellular condensates formed by liquid-liquid phase separation. We analyse the sequence, structure and interactions of caseins in comparison to proteins forming intracellular condensates. Furthermore, we review the similarities between caseins and small heat-shock proteins whose chaperone activity is linked to phase separation of proteins. By bringing these observations together, we describe a regulatory mechanism for protein condensates, as exemplified by casein micelles.
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Affiliation(s)
- Attila Horvath
- John Curtin School of Medical Research, The Australian National University, Acton, ACT, 2601, Australia
| | - Monika Fuxreiter
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi, 58/B 35131, Padova, Italy
| | - Michele Vendruscolo
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom
| | - Carl Holt
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - John A Carver
- Research School of Chemistry, The Australian National University, Acton, ACT, 2601, Australia
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18
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Anselmo S, Sancataldo G, Foderà V, Vetri V. α-casein micelles-membranes interaction: Flower-like lipid protein coaggregates formation. Biochim Biophys Acta Gen Subj 2022; 1866:130196. [PMID: 35724888 DOI: 10.1016/j.bbagen.2022.130196] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 04/28/2022] [Accepted: 06/13/2022] [Indexed: 11/28/2022]
Abstract
BACKGROUND Environmental conditions regulate the association/aggregation states of proteins and their action in cellular compartments. Analysing protein behaviour in presence of lipid membranes is fundamental for the comprehension of many functional and dysfunctional processes. Here, we present an experimental study on the interaction between model membranes and α-casein. α-casein is the major component of milk proteins and it is recognised to play a key role in performing biological functions. The conformational properties of this protein and its capability to form supramolecular structures, like micelles or irreversible aggregates, are key effectors in functional and pathological effects. METHODS By means of quantitative fluorescence imaging and complementary spectroscopic methods, we were able to characterise α-casein association state and the course of events induced by pH changes, which regulate the interaction of this molecule with membranes. RESULTS The study of these complex dynamic events revealed that the initial conformation of the protein critically regulates the fate of α-casein, size and structure of the newly formed aggregates and their effect on membrane structures. Disassembly of micelles due to modification in electrostatic interactions results in increased membrane structure rigidity which accompanies the formation of protein lipid flower-like co-aggregates with protein molecules localised in the external part. GENERAL SIGNIFICANCE These results may contribute to the comprehension of how the initial state of a protein establishes the course of events that occur upon changes in the molecular environment. These events which may occur in cells may be essential to functional, pathological or therapeutical properties specifically associated to casein proteins.
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Affiliation(s)
- Sara Anselmo
- Dipartimento di Fisica e Chimica - Emilio Segré, Università degli Studi di Palermo, Viale delle Scienze ed. 18, 90128 Palermo, Italy
| | - Giuseppe Sancataldo
- Dipartimento di Fisica e Chimica - Emilio Segré, Università degli Studi di Palermo, Viale delle Scienze ed. 18, 90128 Palermo, Italy
| | - Vito Foderà
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Valeria Vetri
- Dipartimento di Fisica e Chimica - Emilio Segré, Università degli Studi di Palermo, Viale delle Scienze ed. 18, 90128 Palermo, Italy.
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19
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Benhamou Goldfajn N, Tang H, Ding F. Substoichiometric Inhibition of Insulin against IAPP Aggregation Is Attenuated by the Incompletely Processed N-Terminus of proIAPP. ACS Chem Neurosci 2022; 13:2006-2016. [PMID: 35704461 DOI: 10.1021/acschemneuro.2c00231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Substoichiometric aggregation inhibition of human islet amyloid polypeptide (IAPP), the hallmark of type 2 diabetes impacting millions of people, is crucial for developing clinic therapies, yet it remains challenging given that many candidate inhibitors require high doses. Intriguingly, insulin, the key regulatory polypeptide on blood glucose levels that are cosynthesized, costored, and cosecreted with IAPP by pancreatic β cells, has been identified as a potent inhibitor that can suppress IAPP amyloid aggregation at substoichiometric concentrations. Here, we computationally investigated the molecular mechanisms of the substoichiometric inhibition of insulin against the aggregation of IAPP and the incompletely processed IAPP (proIAPP) using discrete molecular dynamics simulations. Our results suggest that the amyloid aggregations of both IAPP and proIAPP might be disrupted by insulin through its binding with the shared amyloidogenic core sequences. However, the N-terminus of proIAPP competed with the amyloidogenic core sequences for the insulin interactions, resulting in attenuated inhibition by insulin. Moreover, insulin preferred to bind the elongation surfaces of IAPP seeds with fibril-like structure, with a stronger affinity than that of IAPP monomers. The capping of elongation surfaces by a small amount of insulin sterically prohibited the seed growth via monomer addition, achieving the substoichiometric inhibition. Together, our computational results provided molecular insights for the substoichiometric inhibition of insulin against IAPP aggregation, also the weakened effect on proIAPP. The uncovered substoichiometric inhibition by capping the elongation of amyloid seeds or fibrils may guide the rational designs of new potent inhibitors effective at low doses.
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Affiliation(s)
- Nadav Benhamou Goldfajn
- Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634, United States.,University of Massachusetts, Amherst, Massachusetts 01003, United States
| | - Huayuan Tang
- Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634, United States
| | - Feng Ding
- Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634, United States
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20
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Tang H, Sun Y, Ding F. Hydrophobic/Hydrophilic Ratio of Amphiphilic Helix Mimetics Determines the Effects on Islet Amyloid Polypeptide Aggregation. J Chem Inf Model 2022; 62:1760-1770. [PMID: 35311274 PMCID: PMC9123946 DOI: 10.1021/acs.jcim.1c01566] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Amyloid depositions of human islet amyloid polypeptides (hIAPP) are associated with type II diabetes (T2D) impacting millions of people globally. Accordingly, strategies against hIAPP aggregation are essential for the prevention and eventual treatment of the disease. Helix mimetics, which modulate the protein-protein interaction by mimicking the side chain residues of a natural α-helix, were found to be a promising strategy for inhibiting hIAPP aggregation. Here, we applied molecular dynamics simulations to investigate two helix mimetics reported to have opposite effects on hIAPP aggregation in solution, the oligopyridylamide-based scaffold 1e promoted, whereas naphthalimide-appended oligopyridylamide scaffold DM 1 inhibited the aggregation of hIAPP in solution. We found that 1e promoted hIAPP aggregation because of the recruiting effects through binding with the N-termini of hIAPP peptides. In contrast, DM 1 with a higher hydrophobic/hydrophilic ratio effectively inhibited hIAPP aggregation by strongly binding with the C-termini of hIAPP peptides, which competed for the interpeptide contacts between amyloidogenic regions in the C-termini and impaired the fibrillization of hIAPP. Structural analyses revealed that DM 1 formed the core of hIAPP-DM 1 complexes and stabilized the off-pathway oligomers, whereas 1e formed the corona outside the hIAPP-1e complexes and remained active in recruiting free hIAPP peptides. The distinct interaction mechanisms of DM 1 and 1e, together with other reported potent antagonists in the literature, emphasized the effective small molecule-based amyloid inhibitors by disrupting peptide interactions that should reach a balanced hydrophobic/hydrophilic ratio, providing a viable and generic strategy for the rational design of novel anti-amyloid nanomedicine.
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Affiliation(s)
- Huayuan Tang
- Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634, United States
| | - Yunxiang Sun
- Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634, United States.,Department of Physics, Ningbo University, Ningbo 315211, China
| | - Feng Ding
- Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634, United States
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21
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Quantitative multivalent binding model of the structure, size distribution and composition of the casein micelles of cow milk. Int Dairy J 2022. [DOI: 10.1016/j.idairyj.2021.105292] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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22
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Spatharas PM, Nasi GI, Tsiolaki PL, Theodoropoulou MK, Papandreou NC, Hoenger A, Trougakos IP, Iconomidou VA. Clusterin in Alzheimer's disease: An amyloidogenic inhibitor of amyloid formation? Biochim Biophys Acta Mol Basis Dis 2022; 1868:166384. [DOI: 10.1016/j.bbadis.2022.166384] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 02/20/2022] [Accepted: 03/07/2022] [Indexed: 12/14/2022]
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23
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Fuentes-Lemus E, Jiang S, Hägglund P, Davies MJ. High concentrations of casein proteins exacerbate radical chain reactions and increase the extent of oxidative damage. Food Hydrocoll 2021. [DOI: 10.1016/j.foodhyd.2021.107060] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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24
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Anema SG. Heat-induced changes in caseins and casein micelles, including interactions with denatured whey proteins. Int Dairy J 2021. [DOI: 10.1016/j.idairyj.2021.105136] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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26
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Vollmer AH, Kieferle I, Youssef NN, Kulozik U. Mechanisms of structure formation underlying the creaming reaction in a processed cheese model system as revealed by light and transmission electron microscopy. J Dairy Sci 2021; 104:9505-9520. [DOI: 10.3168/jds.2020-20080] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 04/12/2021] [Indexed: 12/15/2022]
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Vollmer AH, Kieferle I, Pusl A, Kulozik U. Effect of pentasodium triphosphate concentration on physicochemical properties, microstructure, and formation of casein fibrils in model processed cheese. J Dairy Sci 2021; 104:11442-11456. [PMID: 34389148 DOI: 10.3168/jds.2021-20628] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 06/28/2021] [Indexed: 11/19/2022]
Abstract
The effects of varying the concentration of pentasodium triphosphate (PP) emulsifying salt [0, 0.6, 1.2, 1.5, and 1.8%, plus 0.9% of a mixture of citric acid (CA) and disodium phosphate (DSP) to adjust cheese pH to 5.85] on rheological, textural, physicochemical, and microstructural properties were studied in a processed cheese model system containing ~20% micellar casein concentrate, ~20% sunflower oil, and ~59% water. Special emphasis was placed on the unique casein fibrils recently described in a comparable processed cheese model system. Our results show that during processing (90°C, 17.37 rpm over 270 min) the apparent viscosity increased more and faster for formulations containing higher concentrations of PP, in analogy to the so-called creaming reaction, a general thickening of the molten cheese mass with prolonged processing. We found that 1.2% PP (plus 0.9% CA-DSP) appeared to be the threshold for the creaming reaction to take place. With increasing PP concentrations, cheese hardness increased in a sigmoidal fashion, and insoluble (protein-bound) calcium concentration decreased exponentially. Light micrographs of samples taken at the end of processing indicated initially large and dense casein aggregates within the matrix that disappeared with higher levels of PP, in parallel with the development of a finer emulsion. With transmission electron microscopy analysis on the same samples, the highly complex restructuring of the casein matrix was evident; casein fibrils had formed de novo at the periphery of the loosening casein aggregates. With higher levels of PP, amorphous areas were observed in place of the dense casein aggregates that appeared progressively void of protein, whereas fibril concentration increased throughout the rest of the matrix. Fibrils progressively attached to the surface of fat globules, thereby emulsifying them. Reverse-phase HPLC analysis of insoluble and soluble fractions indicated κ-casein to be the most likely constituent of the newly formed fibrils. The results of this study suggest that PP induced a concentration-dependent dissociation of caseins (through increased calcium chelation) and further led to their spatial separation. In essence, their chaperone activity was hindered, which resulted in amorphous aggregation on the one hand and fibril formation on the other.
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Affiliation(s)
- Almut H Vollmer
- Department of Nutrition, Dietetics, and Food Sciences, Utah State University, Logan 84322.
| | - Ingrun Kieferle
- Chair of Food and Bioprocess Engineering, TUM School of Life Sciences, Technical University of Munich, 85354 Freising, Germany
| | - Alexandra Pusl
- Chair of Food and Bioprocess Engineering, TUM School of Life Sciences, Technical University of Munich, 85354 Freising, Germany
| | - Ulrich Kulozik
- Chair of Food and Bioprocess Engineering, TUM School of Life Sciences, Technical University of Munich, 85354 Freising, Germany
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Guarrasi V, Rappa GC, Costa MA, Librizzi F, Raimondo M, Di Stefano V, Germanà MA, Vilasi S. Valorization of Apple Peels through the Study of the Effects on the Amyloid Aggregation Process of κ-Casein. Molecules 2021; 26:molecules26082371. [PMID: 33921801 PMCID: PMC8073991 DOI: 10.3390/molecules26082371] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Revised: 04/13/2021] [Accepted: 04/15/2021] [Indexed: 01/13/2023] Open
Abstract
Waste valorization represents one of the main social challenges when promoting a circular economy and environmental sustainability. Here, we evaluated the effect of the polyphenols extracted from apple peels, normally disposed of as waste, on the amyloid aggregation process of κ-casein from bovine milk, a well-used amyloidogenic model system. The effect of the apple peel extract on protein aggregation was examined using a thioflavin T fluorescence assay, Congo red binding assay, circular dichroism, light scattering, and atomic force microscopy. We found that the phenolic extract from the peel of apples of the cultivar “Fuji”, cultivated in Sicily (Caltavuturo, Italy), inhibited κ-casein fibril formation in a dose-dependent way. In particular, we found that the extract significantly reduced the protein aggregation rate and inhibited the secondary structure reorganization that accompanies κ-casein amyloid formation. Protein-aggregated species resulting from the incubation of κ-casein in the presence of polyphenols under amyloid aggregation conditions were reduced in number and different in morphology.
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Affiliation(s)
- Valeria Guarrasi
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Via Ugo La Malfa 153, 90146 Palermo, Italy; (G.C.R.); (M.A.C.); (F.L.); (M.R.); (S.V.)
- Correspondence: ; Tel.: +39-0916809356
| | - Giacoma Cinzia Rappa
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Via Ugo La Malfa 153, 90146 Palermo, Italy; (G.C.R.); (M.A.C.); (F.L.); (M.R.); (S.V.)
| | - Maria Assunta Costa
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Via Ugo La Malfa 153, 90146 Palermo, Italy; (G.C.R.); (M.A.C.); (F.L.); (M.R.); (S.V.)
| | - Fabio Librizzi
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Via Ugo La Malfa 153, 90146 Palermo, Italy; (G.C.R.); (M.A.C.); (F.L.); (M.R.); (S.V.)
| | - Marco Raimondo
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Via Ugo La Malfa 153, 90146 Palermo, Italy; (G.C.R.); (M.A.C.); (F.L.); (M.R.); (S.V.)
| | - Vita Di Stefano
- Dipartimento Scienze e Tecnologie Biologiche Chimiche e Farmaceutiche, Università degli Studi di Palermo, Via Archirafi 32, 90123 Palermo, Italy;
| | - Maria Antonietta Germanà
- Dipartimento di Scienze Agrarie, Alimentari e Forestali, Università degli Studi di Palermo, Viale delle Scienze Ed. 4, 90128 Palermo, Italy;
| | - Silvia Vilasi
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Via Ugo La Malfa 153, 90146 Palermo, Italy; (G.C.R.); (M.A.C.); (F.L.); (M.R.); (S.V.)
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29
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Wang J, Liu J, Du G, An Y, Zhao C, Zeng B. The Influence of Ca 2+ and Zn 2+ on the Amyloid Fibril Formation by β-Casein. Protein Pept Lett 2021; 27:915-922. [PMID: 32186269 DOI: 10.2174/0929866527666200318143533] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Revised: 01/08/2020] [Accepted: 01/15/2020] [Indexed: 12/22/2022]
Abstract
BACKGROUND The amyloid fibril formation in different tissues or organs is related to amyloidosis. The Ca2+, Zn2+ and heparan sulfate (HS) are important elements and compositions in human body, which play a key role in regulating various physiological activities. Recently, there are increasing evidence suggest that they are closely linked to the amyloid fibril formation. OBJECTIVE The effect of Ca2+ and Zn2+ on the amyloid fibril formation by β-casein was investigated in the absence and presence of HS, which was significantly to explore the relationship between the concentration changes of Ca2+ and Zn2+ and amyloid fibril formation. METHODS In this work, the influence of Ca2+ and Zn2+ on the β-casein fibril formation in the absence and presence of HS was investigated by various methods of Thioflavin T fluorescence assay, transmission electron microscopy and intrinsic fluorescence measure. RESULTS The results demonstrated that Ca2+ and Zn2+ promoted the β-casein fibril formation. The effect of Ca2+ was greater than that of Zn2+. Meanwhile, the both metal ions had stronger effects when β-casein was incubated with HS together. In addition, it was also observed that the microenvironment of β-casein was changed because the intrinsic fluorescence peaks were red-shifted on the influence of Ca2+ and Zn2+. CONCLUSION Ca2+ and Zn2+ were capable of promoting the β-casein fibril formation in the both absence and presence of HS. This work set up the foundation for further researching of the amyloidosis pathogenesis and provided new insight for us to understand relationship between the inflammation and amyloidosis.
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Affiliation(s)
- Jia Wang
- Pharmacy College, Jilin University, Changchun, China
| | - Jihua Liu
- Pharmacy College, Jilin University, Changchun, China
| | - Guangguang Du
- Pharmacy College, Jilin University, Changchun, China
| | - Yang An
- Pharmacy College, Jilin University, Changchun, China
| | - Chunfang Zhao
- Pharmacy College, Jilin University, Changchun, China
| | - Baohua Zeng
- Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, China
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Marzano NR, Wray KM, Johnston CL, Paudel BP, Hong Y, van Oijen A, Ecroyd H. An α-Cyanostilbene Derivative for the Enhanced Detection and Imaging of Amyloid Fibril Aggregates. ACS Chem Neurosci 2020; 11:4191-4202. [PMID: 33226775 DOI: 10.1021/acschemneuro.0c00478] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The aggregation of proteins into amyloid fibrils has been implicated in the pathogenesis of a variety of neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease. Benzothiazole dyes such as Thioflavin T (ThT) are well-characterized and widely used fluorescent probes for monitoring amyloid fibril formation. However, existing dyes lack sensitivity and specificity to oligomeric intermediates formed during fibril formation. In this work, we describe the use of an α-cyanostilbene derivative (called ASCP) with aggregation-induced emission properties as a fluorescent probe for the detection of amyloid fibrils. Similar to ThT, ASCP is fluorogenic in the presence of amyloid fibrils and, upon binding and excitation at 460 nm, produces a red-shifted emission with a large Stokes shift of 145 nm. ASCP has a higher binding affinity to fibrillar α-synuclein than ThT and likely shares the same binding sites to amyloid fibrils. Importantly, ASCP was found to also be fluorogenic in the presence of amorphous aggregates and can detect oligomeric species formed early during aggregation. Moreover, ASCP can be used to visualize fibrils via total internal reflection fluorescence microscopy and, due to its large Stokes shift, simultaneously monitor the fluorescence emission of other labelled proteins following excitation with the same laser used to excite ASCP. Consequently, ASCP possesses enhanced and unique spectral characteristics compared to ThT that make it a promising alternative for the in vitro study of amyloid fibrils and the mechanisms by which they form.
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Affiliation(s)
- Nicholas R. Marzano
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia
- Illawarra Health & Medical Research Institute, Wollongong, New South Wales 2522, Australia
| | - Kelly M. Wray
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia
- Illawarra Health & Medical Research Institute, Wollongong, New South Wales 2522, Australia
| | - Caitlin L. Johnston
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia
- Illawarra Health & Medical Research Institute, Wollongong, New South Wales 2522, Australia
| | - Bishnu P. Paudel
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia
- Illawarra Health & Medical Research Institute, Wollongong, New South Wales 2522, Australia
| | - Yuning Hong
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Antoine van Oijen
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia
- Illawarra Health & Medical Research Institute, Wollongong, New South Wales 2522, Australia
| | - Heath Ecroyd
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia
- Illawarra Health & Medical Research Institute, Wollongong, New South Wales 2522, Australia
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Thorn DC, Bahraminejad E, Grosas AB, Koudelka T, Hoffmann P, Mata JP, Devlin GL, Sunde M, Ecroyd H, Holt C, Carver JA. Native disulphide-linked dimers facilitate amyloid fibril formation by bovine milk α S2-casein. Biophys Chem 2020; 270:106530. [PMID: 33545456 DOI: 10.1016/j.bpc.2020.106530] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 12/12/2020] [Accepted: 12/12/2020] [Indexed: 12/22/2022]
Abstract
Bovine milk αS2-casein, an intrinsically disordered protein, readily forms amyloid fibrils in vitro and is implicated in the formation of amyloid fibril deposits in mammary tissue. Its two cysteine residues participate in the formation of either intra- or intermolecular disulphide bonds, generating monomer and dimer species. X-ray solution scattering measurements indicated that both forms of the protein adopt large, spherical oligomers at 20 °C. Upon incubation at 37 °C, the disulphide-linked dimer showed a significantly greater propensity to form amyloid fibrils than its monomeric counterpart. Thioflavin T fluorescence, circular dichroism and infrared spectra were consistent with one or both of the dimer isomers (in a parallel or antiparallel arrangement) being predisposed toward an ordered, amyloid-like structure. Limited proteolysis experiments indicated that the region from Ala81 to Lys113 is incorporated into the fibril core, implying that this region, which is predicted by several algorithms to be amyloidogenic, initiates fibril formation of αS2-casein. The partial conservation of the cysteine motif and the frequent occurrence of disulphide-linked dimers in mammalian milks despite the associated risk of mammary amyloidosis, suggest that the dimeric conformation of αS2-casein is a functional, yet amyloidogenic, structure.
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Affiliation(s)
- David C Thorn
- Research School of Chemistry, The Australian National University, Acton, ACT 2601, Australia
| | - Elmira Bahraminejad
- Research School of Chemistry, The Australian National University, Acton, ACT 2601, Australia
| | - Aidan B Grosas
- Research School of Chemistry, The Australian National University, Acton, ACT 2601, Australia
| | - Tomas Koudelka
- Institute of Experimental Medicine, University of Kiel, Kiel 24105, Germany
| | - Peter Hoffmann
- Future Industries Institute, University of South Australia, Mawson Lakes, SA 5095, Australia
| | - Jitendra P Mata
- Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW 2234, Australia
| | - Glyn L Devlin
- Victorian Health and Human Services Building Authority, Melbourne, Victoria 3000, Australia
| | - Margaret Sunde
- Discipline of Pharmacology, School of Medical Sciences, Faculty of Medicine and Health and Sydney Nano, University of Sydney, Sydney, NSW 2006, Australia
| | - Heath Ecroyd
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong and Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Carl Holt
- Institute of Molecular, Cell & Systems Biology, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
| | - John A Carver
- Research School of Chemistry, The Australian National University, Acton, ACT 2601, Australia.
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Sarreshtehdari N, Mohseni-Shahri FS, Moeinpour F. Bovine β-casein binding studies of a Schiff base ligand: fluorescence and circular dichroism approaches. LUMINESCENCE 2020; 36:360-366. [PMID: 32945077 DOI: 10.1002/bio.3951] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 07/20/2020] [Accepted: 09/07/2020] [Indexed: 12/14/2022]
Abstract
In this study, a Schiff base derived from a heterocyclic moiety was synthesized and characterized. The in vitro binding behaviour of this ligand with β-casein (β-CN) was investigated using biophysical techniques. For evaluation, thermodynamics variables of interactions between the Schiff base ligand and β-CN, such as fluorescence at different temperatures, were measured. The results showed that the Schiff base ligand possessed considerable associated binding to β-CN and that the procedure was enthalpy driven. The β-CN conformation was also changed to give a further unfolded structure. Fluorescence resonance energy transfer was used to estimate the interval between donor (β-CN) and acceptor (Schiff base ligand). All these experimental results proposed that β-CN might act as carrier protein for the Schiff base ligand to deliver it to the target molecules.
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Affiliation(s)
- Nooshin Sarreshtehdari
- Department of Chemistry, Bandar Abbas Branch, Islamic Azad University, Bandar Abbas, Iran
| | | | - Farid Moeinpour
- Department of Chemistry, Bandar Abbas Branch, Islamic Azad University, Bandar Abbas, Iran
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33
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Ghosh P, De P. Modulation of Amyloid Protein Fibrillation by Synthetic Polymers: Recent Advances in the Context of Neurodegenerative Diseases. ACS APPLIED BIO MATERIALS 2020; 3:6598-6625. [DOI: 10.1021/acsabm.0c01021] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Pooja Ghosh
- Polymer Research Centre and Centre for Advanced Functional Materials, Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, 741246 Nadia, West Bengal, India
| | - Priyadarsi De
- Polymer Research Centre and Centre for Advanced Functional Materials, Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, 741246 Nadia, West Bengal, India
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Jahandari N, Mohseni-Shahri FS, Moeinpour F. Synthesis and Characterization of Cobalt(II) and Manganese(II) Schiff Base Complexes: Metal Effect on the Binding Affinity with β-Casein. J Fluoresc 2020; 30:1575-1582. [PMID: 32870454 DOI: 10.1007/s10895-020-02612-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 08/24/2020] [Indexed: 10/23/2022]
Abstract
In this study, two metal Schiff base complexes (cobalt(II) and manganese(II), were synthesized and characterized by 1H-NMR and FT-IR analyses. The in vitro binding behavior of this complexes with β-Casein (β-CN) was investigated by using biophysical techniques. For evaluation the thermodynamics parameters of interaction between Schiff base complexes and β-CN,the fluorescence data at different temperatures were done. The results showed that the intrinsic fluorescence of the β-CN was quenched by increasing the complexes through the dynamic quenching mechanism. Also, these complexes demonstrated a considrable binding affinity to β-CN and the process is mainly entropy driven. Fluorescence resonance energy transfer was used in order to estimating the distance between donor (β-CN) and acceptor (complex). Results demonstrated that the sequence of tendency of the complexes to β-CN was as follows: Mn-Schiff base complex > Co-Schiff base complex. All these experimental results propose that β-CN might act as carrier protein for Co(II) and Mn (II) complexes to deliver it to the target molecules.
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Affiliation(s)
- Nafiseh Jahandari
- Department of Chemistry, Islamic Azad University, Bandar Abbas Branch, Bandar Abbas, Iran
| | | | - Farid Moeinpour
- Department of Chemistry, Islamic Azad University, Bandar Abbas Branch, Bandar Abbas, Iran
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35
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Chanphai P, Bourassa P, Tajmir-Riahi HA. An Overview of the Loading Efficacy of Cationic Lipids with Milk Proteins: A Potential Application for Lipid Delivery. Curr Med Chem 2020; 27:4109-4117. [DOI: 10.2174/0929867325666180608122439] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Revised: 03/29/2018] [Accepted: 03/29/2018] [Indexed: 11/22/2022]
Abstract
In this review, the loading efficacies of helper and Cationic Lipids Cholesterol
(CHOL), 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP), Dioctadecyl Dimethyl-
Ammonium Bromide (DDAB) and Dioleoyl Phosphatidylethanolamine (DOPE) with milk β-
lactoglobulin, α-casein and β-casein were compared in aqueous solution at physiological conditions.
Structural analysis showed that lipids bind milk proteins via hydrophilic, hydrophobic
and H-bonding contacts with DOTAP and DDAB forming more stable protein conjugates.
Loading efficacy was 30-50% and enhanced with cationic lipids. Lipid conjugation altered
protein conformation, causing a partial protein structural destabilization. Milk proteins are
capable of transporting lipids in vitro.
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Affiliation(s)
- Penprapa Chanphai
- Department de Chemistry-Biochemistry, University of Quebec a Trois-Rivieres, C.P. 500, Trois-Rivieres (Quebec) G9A 5H7, Canada
| | - Philippe Bourassa
- Department de Chemistry-Biochemistry, University of Quebec a Trois-Rivieres, C.P. 500, Trois-Rivieres (Quebec) G9A 5H7, Canada
| | - Heidar Ali Tajmir-Riahi
- Department de Chemistry-Biochemistry, University of Quebec a Trois-Rivieres, C.P. 500, Trois-Rivieres (Quebec) G9A 5H7, Canada
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Lazzaro F, Bouchoux A, Raynes J, Williams R, Ong L, Hanssen E, Lechevalier V, Pezennec S, Cho HJ, Logan A, Gras S, Gaucheron F. Tailoring the structure of casein micelles through a multifactorial approach to manipulate rennet coagulation properties. Food Hydrocoll 2020. [DOI: 10.1016/j.foodhyd.2019.105414] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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37
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Yan C, Zhou Z. Ellagic acid can act as a chaperone and suppress the heat-induced amyloid-like aggregation of ovalbumin. Food Hydrocoll 2020. [DOI: 10.1016/j.foodhyd.2019.105408] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Bhat MY, Singh LR, Dar TA. Taurine Induces an Ordered but Functionally Inactive Conformation in Intrinsically Disordered Casein Proteins. Sci Rep 2020; 10:3503. [PMID: 32103094 PMCID: PMC7044306 DOI: 10.1038/s41598-020-60430-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 01/31/2020] [Indexed: 11/30/2022] Open
Abstract
Intrinsically disordered proteins (IDPs) are involved in various important biological processes, such as cell signalling, transcription, translation, cell division regulation etc. Many IDPs need to maintain their disordered conformation for proper function. Osmolytes, natural organic compounds responsible for maintaining osmoregulation, have been believed to regulate the functional activity of macromolecules including globular proteins and IDPs due to their ability of modulating the macromolecular structure, conformational stability, and functional integrity. In the present study, we have investigated the effect of all classes of osmolytes on two model IDPs, α- and β-casein. It was observed that osmolytes can serve either as folding inducers or folding evaders. Folding evaders, in general, do not induce IDP folding and therefore had no significant effect on structural and functional integrity of IDPs. On the other hand, osmolytes taurine and TMAO serve as folding inducers by promoting structural collapse of IDPs that eventually leads to altered structural and functional integrity of IDPs. This study sheds light on the osmolyte-induced regulation of IDPs and their possible role in various disease pathologies.
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Affiliation(s)
- Mohd Younus Bhat
- Department of Clinical Biochemistry, University of Kashmir, Srinagar, J&K, 190006, India
| | | | - Tanveer Ali Dar
- Department of Clinical Biochemistry, University of Kashmir, Srinagar, J&K, 190006, India.
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39
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Ma W, Tribet C, Guyot S, Zanchi D. Tannin-controlled micelles and fibrils of κ-casein. J Chem Phys 2020; 151:245103. [PMID: 31893889 DOI: 10.1063/1.5128057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Effects of green tea tannin epigallocatechin-gallate (EGCG) on thermal-stress-induced amyloid fibril formation of reduced carboxymethylated bovine milk protein κ-casein were studied by dynamical light scattering and small angle X-ray scattering (SAXS). Two populations of aggregates, micelles, and fibrils dominated the time evolution of light scattering intensity and of effective hydrodynamic diameter. SAXS experiments allowed us to resolve micelles and fibrils so that the time dependence of the scattering profile revealed the structural evolution of the two populations. The low-Q scattering intensity prior to an expected increase in time due to fibril growth shows an intriguing rapid decrease, which is interpreted as the release of monomers from micelles. This phenomenon, observed both in the absence and in the presence of EGCG, indicates that under thermal stress free conditions, native monomers are converted to amyloid-prone monomers that do not form micelles. The consumption of free native monomers results in a release of native monomers from micelles because only native proteins participate in micelle-monomer (quasi)equilibrium. This release is reversible, indicating also that native-to-amyloid-prone monomer conversion is reversible as well. We show that EGCG does not bind to protein in fibrils, neither does it affect/prevent the proamyloid conversion of monomers. EGCG hinders the addition of monomers to growing fibrils. These facts allowed us to propose the kinetics model for EGCG-controlled amyloid aggregation of micellar proteins. Therein, we introduced the growth-rate inhibition function, which quantitatively accounts for the effect of EGCG on the fibril growth at any degree of thermal stress.
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Affiliation(s)
- Wei Ma
- PASTEUR, Département de Chimie, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 24 rue Lhomond, F-75005 Paris, France
| | - Christophe Tribet
- PASTEUR, Département de Chimie, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 24 rue Lhomond, F-75005 Paris, France
| | - Sylvain Guyot
- INRA UR1268 BIA-Polyphenols, Reactivity, Processes, F-35653 Le Rheu, France
| | - Dražen Zanchi
- PASTEUR, Département de Chimie, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 24 rue Lhomond, F-75005 Paris, France
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40
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Wang J, Zhu H, Gan H, Meng Q, Du G, An Y, Liu J. The effect of heparan sulfate on promoting amyloid fibril formation by β-casein and their binding research with multi-spectroscopic approaches. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2019; 202:111671. [PMID: 31731076 DOI: 10.1016/j.jphotobiol.2019.111671] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 09/27/2019] [Accepted: 10/24/2019] [Indexed: 11/15/2022]
Abstract
As a molecular chaperone, β-casein is difficult to form amyloid fibrils under physiological conditions due to its chaperone activity. Heparan sulfate (HS) has drawn attention of technologists all over the word because of its relation to amyloid deposits in some amyloidosis diseases. For better understanding the relationship between the β-casein and HS, the multi-spectroscopic studies were employed. The data of thioflavin T (ThT) binding assay, transmission electron microscopy (TEM) and circular dichroism (CD) demonstrated that HS promoted fibril formation by β-casein in the amount and the growth speed. The results of steady-state UV-vis absorption spectra, fluorescence spectroscopy and fluorescence lifetime revealed that the β-casein-HS complexes were formed and HS quenched the fluorescence of β-casein by a static quenching mechanism. On the basis of fluorescence analysis, the value of binding constant was equal to 1.17 × 107 L mol-1 at 338.15 K and there was about one binding site between them. According to thermodynamic parameters obtained, it was deduced that a spontaneous reaction happened, and protein-ligand complex was stabilized by hydrogen bonds and hydrophobic interaction. Furthermore, using fluorescence resonance energy transfer (FRET) assay, the value of binding distance between HS and Trp143 of β-casein was calculated to be 0.93 nm. Finally, on the basis of synchronous fluorescence experiment, the polarity increasing and hydrophobicity decreasing around Trp143 occurred during the period of fibril formation by β-casein.
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Affiliation(s)
- Jia Wang
- Pharmacy College, Jilin University, Changchun 130021, PR China
| | - He Zhu
- College of Environmental and Resource Sciences, Jilin Agricultural University, Changchun 130118, PR China
| | - Huizhu Gan
- China-Japan Union Hospital, Jilin University, Changchun 130021, PR China
| | - Qin Meng
- Pharmacy College, Jilin University, Changchun 130021, PR China
| | - Guangguang Du
- Pharmacy College, Jilin University, Changchun 130021, PR China
| | - Yang An
- Pharmacy College, Jilin University, Changchun 130021, PR China
| | - Jihua Liu
- Pharmacy College, Jilin University, Changchun 130021, PR China.
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41
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Inhibition of amyloid beta toxicity in zebrafish with a chaperone-gold nanoparticle dual strategy. Nat Commun 2019; 10:3780. [PMID: 31439844 PMCID: PMC6706415 DOI: 10.1038/s41467-019-11762-0] [Citation(s) in RCA: 115] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 08/04/2019] [Indexed: 12/22/2022] Open
Abstract
Alzheimer’s disease (AD) is the most prevalent form of neurodegenerative disorders, yet no major breakthroughs have been made in AD human trials and the disease remains a paramount challenge and a stigma in medicine. Here we eliminate the toxicity of amyloid beta (Aβ) in a facile, high-throughput zebrafish (Danio rerio) model using casein coated-gold nanoparticles (βCas AuNPs). βCas AuNPs in systemic circulation translocate across the blood brain barrier of zebrafish larvae and sequester intracerebral Aβ42 and its elicited toxicity in a nonspecific, chaperone-like manner. This is evidenced by behavioral pathology, reactive oxygen species and neuronal dysfunction biomarkers assays, complemented by brain histology and inductively coupled plasma-mass spectroscopy. We further demonstrate the capacity of βCas AuNPs in recovering the mobility and cognitive function of adult zebrafish exposed to Aβ. This potent, safe-to-use, and easy-to-apply nanomedicine may find broad use for eradicating toxic amyloid proteins implicated in a range of human diseases. Treating Alzheimer’s disease, one of the most common neurodegenerative diseases, is of wide interest. Here, the authors report on the development of casein coated gold nanoparticles which were able to cross the blood brain barrier and protect against amyloid beta toxicity in a zebrafish model.
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42
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Chinak OA, Shernyukov AV, Ovcherenko SS, Sviridov EA, Golyshev VM, Fomin AS, Pyshnaya IA, Kuligina EV, Richter VA, Bagryanskaya EG. Structural and Aggregation Features of a Human κ-Casein Fragment with Antitumor and Cell-Penetrating Properties. Molecules 2019; 24:E2919. [PMID: 31408975 PMCID: PMC6721048 DOI: 10.3390/molecules24162919] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 08/06/2019] [Accepted: 08/09/2019] [Indexed: 11/23/2022] Open
Abstract
Intrinsically disordered proteins play a central role in dynamic regulatory and assembly processes in the cell. Recently, a human κ-casein proteolytic fragment called lactaptin (8.6 kDa) was found to induce apoptosis of human breast adenocarcinoma MCF-7 and MDA-MB-231 cells with no cytotoxic activity toward normal cells. Earlier, we had designed some recombinant analogs of lactaptin and compared their biological activity. Among these analogs, RL2 has the highest antitumor activity, but the amino acid residues and secondary structures that are responsible for RL2's activity remain unclear. To elucidate the structure-activity relations of RL2, we studied the structural and aggregation features of this fairly large intrinsically disordered fragment of human milk κ-casein by a combination of physicochemical methods: NMR, paramagnetic relaxation enhancement (PRE), Electron Paramagnetic Resonance (EPR), circular dichroism, dynamic light scattering, atomic force microscopy, and a cytotoxic activity assay. It was found that in solution, RL2 exists as stand-alone monomeric particles and large aggregates. Whereas the disulfide-bonded homodimer turned out to be more prone to assembly into large aggregates, the monomer predominantly forms single particles. NMR relaxation analysis of spin-labeled RL2 showed that the RL2 N-terminal region, which is essential not only for multimerization of the peptide but also for its proapoptotic action on cancer cells, is more ordered than its C-terminal counterpart and contains a site with a propensity for α-helical secondary structure.
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Affiliation(s)
- Olga A Chinak
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk 630090, Russia
| | - Andrey V Shernyukov
- N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry SB RAS, Novosibirsk 630090, Russia
- Department of Natural Sciences, Novosibirsk State University, 1 Pirogova Str., Novosibirsk 630090, Russia
| | - Sergey S Ovcherenko
- N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry SB RAS, Novosibirsk 630090, Russia
- Department of Natural Sciences, Novosibirsk State University, 1 Pirogova Str., Novosibirsk 630090, Russia
| | - Evgeniy A Sviridov
- N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry SB RAS, Novosibirsk 630090, Russia
- Department of Natural Sciences, Novosibirsk State University, 1 Pirogova Str., Novosibirsk 630090, Russia
| | - Victor M Golyshev
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk 630090, Russia
| | - Alexander S Fomin
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk 630090, Russia
| | - Inna A Pyshnaya
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk 630090, Russia
| | - Elena V Kuligina
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk 630090, Russia
| | - Vladimir A Richter
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk 630090, Russia
| | - Elena G Bagryanskaya
- N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry SB RAS, Novosibirsk 630090, Russia.
- Department of Natural Sciences, Novosibirsk State University, 1 Pirogova Str., Novosibirsk 630090, Russia.
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43
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Sequence characteristics responsible for protein‐protein interactions in the intrinsically disordered regions of caseins, amelogenins, and small heat‐shock proteins. Biopolymers 2019; 110:e23319. [DOI: 10.1002/bip.23319] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 06/11/2019] [Accepted: 06/19/2019] [Indexed: 01/01/2023]
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44
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Cao Y, Mezzenga R. Food protein amyloid fibrils: Origin, structure, formation, characterization, applications and health implications. Adv Colloid Interface Sci 2019; 269:334-356. [PMID: 31128463 DOI: 10.1016/j.cis.2019.05.002] [Citation(s) in RCA: 252] [Impact Index Per Article: 50.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 04/30/2019] [Accepted: 05/01/2019] [Indexed: 01/27/2023]
Abstract
Amyloid fibrils have traditionally been considered only as pathological aggregates in human neurodegenerative diseases, but it is increasingly becoming clear that the propensity to form amyloid fibrils is a generic property for all proteins, including food proteins. Differently from the pathological amyloid fibrils, those derived from food proteins can be used as advanced materials in biomedicine, tissue engineering, environmental science, nanotechnology, material science as well as in food science, owing to a combination of highly desirable feature such as extreme aspect ratios, outstanding stiffness and a broad availability of functional groups on their surfaces. In food science, protein fibrillization is progressively recognized as an appealing strategy to broaden and improve food protein functionality. This review article discusses the various classes of reported food protein amyloid fibrils and their formation conditions. It furthermore considers amyloid fibrils in a broad context, from their structural characterization to their forming mechanisms and ensued physical properties, emphasizing their applications in food-related fields. Finally, the biological fate and the potential toxicity mechanisms of food amyloid fibrils are discussed, and an experimental protocol for their health safety validation is proposed in the concluding part of the review.
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Affiliation(s)
- Yiping Cao
- Food and Soft Materials, Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, Zurich 8092, Switzerland
| | - Raffaele Mezzenga
- Food and Soft Materials, Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, Zurich 8092, Switzerland.
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Lambrecht MA, Jansens KJ, Rombouts I, Brijs K, Rousseau F, Schymkowitz J, Delcour JA. Conditions Governing Food Protein Amyloid Fibril Formation. Part II: Milk and Legume Proteins. Compr Rev Food Sci Food Saf 2019; 18:1277-1291. [DOI: 10.1111/1541-4337.12465] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 04/26/2019] [Accepted: 05/16/2019] [Indexed: 02/06/2023]
Affiliation(s)
- Marlies A. Lambrecht
- Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe)KU Leuven Kasteelpark Arenberg 20 B‐3001 Leuven Belgium
| | - Koen J.A. Jansens
- Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe)KU Leuven Kasteelpark Arenberg 20 B‐3001 Leuven Belgium
| | - Ine Rombouts
- Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe)KU Leuven Kasteelpark Arenberg 20 B‐3001 Leuven Belgium
| | - Kristof Brijs
- Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe)KU Leuven Kasteelpark Arenberg 20 B‐3001 Leuven Belgium
| | - Frederic Rousseau
- Switch LaboratoryVIB B‐3000 Leuven Belgium
- Dept. of Cellular and Molecular MedicineKU Leuven B‐3000 Leuven Belgium
| | - Joost Schymkowitz
- Switch LaboratoryVIB B‐3000 Leuven Belgium
- Dept. of Cellular and Molecular MedicineKU Leuven B‐3000 Leuven Belgium
| | - Jan A. Delcour
- Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe)KU Leuven Kasteelpark Arenberg 20 B‐3001 Leuven Belgium
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Characterization of structural conformers of κ-casein utilizing fluorescence spectroscopy. Int J Biol Macromol 2019; 131:89-96. [DOI: 10.1016/j.ijbiomac.2019.03.040] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 03/02/2019] [Accepted: 03/05/2019] [Indexed: 11/21/2022]
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Protein misfolding, aggregation and mechanism of amyloid cytotoxicity: An overview and therapeutic strategies to inhibit aggregation. Int J Biol Macromol 2019; 134:1022-1037. [PMID: 31128177 DOI: 10.1016/j.ijbiomac.2019.05.109] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 05/18/2019] [Accepted: 05/18/2019] [Indexed: 12/18/2022]
Abstract
Protein and peptides are converted from their soluble forms into highly ordered fibrillar aggregates under various conditions inside the cell. Such transitions confer diverse neurodegenerative diseases including Alzheimer's disease, Huntington's disease Prion's disease, Parkinson's disease, polyQ and share abnormal folding of potentially cytotoxic protein species linked with degeneration and death of precise neuronal populations. Presently, major advances are made to understand and get detailed insight into the structural basis and mechanism of amyloid formation, cytotoxicity and therapeutic approaches to combat them. Here we highlight classifies and summarizes the detailed overview of protein misfolding and aggregation at their molecular level including the factors that promote protein aggregation under in vivo and in vitro conditions. In addition, we describe the recent technologies that aid the characterization of amyloid aggregates along with several models that might be responsible for amyloid induced cytotoxicity to cells. Overview on the inhibition of amyloidosis by targeting different small molecules (both natural and synthetic origin) have been also discussed, that provides important approaches to identify novel targets and develop specific therapeutic strategies to combat protein aggregation related neurodegenerative diseases.
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Katouzian I, Jafari SM. Protein nanotubes as state-of-the-art nanocarriers: Synthesis methods, simulation and applications. J Control Release 2019; 303:302-318. [PMID: 31009647 DOI: 10.1016/j.jconrel.2019.04.026] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 04/16/2019] [Accepted: 04/17/2019] [Indexed: 12/16/2022]
Abstract
Application of food proteins as a tool to form nanostructures (especially nanotubular shapes) has been an interesting topic for both the food and pharmaceutical sectors. Organic and protein nanostructures have better biocompatibility and biodegradability compared to inorganic counterparts like carbon nanotubes; in addition, they can undergo surface modifications. Several organic nanotubes have been developed, meanwhile, the engineered protein nanotubes in the food science have been prepared from α-lactalbumin, ovalbumin, cyclic peptide nanotubes, collagen, bovine serum albumin, lysozyme and hydrophobins which are of great interest to be applied in the food industry considering their outstanding properties. This revision underlines the production of protein nanotubular structures and their applications as well as introducing the in silico studies which is a novel field in predicting the interactions of proteins with different molecules before running experimental tests and finally exploring the safety of protein nanotubes. Protein nanotubes have several advantages over other morphologies, such as the functionalizing ability of both the outer and inner layers, enabling an efficient delivery and controlled release and their ability as gelling agents. Also, regarding their natural source in foods, they are promising alternatives to carbon nanotubes.
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Affiliation(s)
- Iman Katouzian
- Department of Food Materials and Process Design Engineering, Gorgan University of Agricultural Science and Natural Resources, Gorgan, Iran; Nano-encapsulation in the Food, Nutraceutical, and Pharmaceutical Industries Group (NFNPIG), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Seid Mahdi Jafari
- Department of Food Materials and Process Design Engineering, Gorgan University of Agricultural Science and Natural Resources, Gorgan, Iran.
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Melnikova DL, Skirda VD, Nesmelova IV. Effect of Reducing Agent TCEP on Translational Diffusion and Supramolecular Assembly in Aqueous Solutions of α-Casein. J Phys Chem B 2019; 123:2305-2315. [PMID: 30789730 DOI: 10.1021/acs.jpcb.8b12511] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The translational diffusion coefficient is highly sensitive to the size change of diffusing species and is ideally suited for the study of molecular association. Here, we used translational diffusion measurements by a pulsed-field gradient nuclear magnetic resonance (PFG NMR) technique to investigate the role of disulfide bonds in the formation of a supramolecular gel-like structure in the concentrated solution of α-casein. To reduce disulfide bonds, we added a commonly used reducing reagent tris(2-carboxyethyl)phosphine (TCEP) to α-casein solution. We found that the disruption of a disulfide bond Cys36-Cys40 in αs2-casein does not alter the translational diffusion or secondary structure of α-casein in dilute, 1 and 3% (wt %) solution. On the contrary, in concentrated, 15% (wt %) α-casein solution, in addition to the disruption of disulfide bonds, TCEP induced significant changes in gel properties. New long-lived intermolecular interactions formed, leading to the irreversible gel formation. While a few side reactions of TCEP (as well as other reducing agents, e.g., dithiothreitol) have been reported, this area is still understudied. Here, we provide new data on the side reaction of the reducing agent TCEP in concentrated protein solution, suggesting that at high protein concentrations TCEP should be used with caution.
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Affiliation(s)
- Daria L Melnikova
- Department of Physics , Kazan Federal University , Kazan 420011 , Russia
| | - Vladimir D Skirda
- Department of Physics , Kazan Federal University , Kazan 420011 , Russia
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Carver JA, Holt C. Functional and dysfunctional folding, association and aggregation of caseins. PROTEIN MISFOLDING 2019; 118:163-216. [DOI: 10.1016/bs.apcsb.2019.09.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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