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Qiao Q, Wei G, Song Z. Structural diversity in the membrane-bound hIAPP dimer correlated with distinct membrane disruption mechanisms. Phys Chem Chem Phys 2024; 26:7090-7102. [PMID: 38345763 DOI: 10.1039/d3cp05887e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
Amyloid deposits of the human islet amyloid polypeptide (hIAPP) have been identified in 90% of patients with type II diabetes. Cellular membranes accelerate the hIAPP fibrillation, and the integrity of membranes is also disrupted at the same time, leading to the apoptosis of β cells in pancreas. The molecular mechanism of hIAPP-induced membrane disruption, especially during the initial membrane disruption stage, has not been well understood yet. Herein, we carried out extensive all-atom molecular dynamics simulations investigating the hIAPP dimerization process in the anionic POPG membrane, to provide the detailed molecular mechanisms during the initial hIAPP aggregation stage in the membrane environment. Compared to the hIAPP monomer on the membrane, we observed not only an increase of α-helical structures, but also a substantial increase of β-sheet structures upon spontaneous dimerization. Moreover, the random coiled and α-helical dimer structures insert deep into the membrane interior with a few inter-chain contacts at the C-terminal region, while the β-sheet-rich structures reside on the membrane surface accompanied by strong inter-chain hydrophobic interactions. The coexistence of α and β structures constitutes a diverse structural ensemble of the membrane-bound hIAPP dimer. From α-helical to β-sheet structures, the degree of membrane disruption decreases gradually, and thus the membrane damage induced by random coiled and α-helical structures precedes that induced by β-sheet structures. We speculate that insertion of random coiled and α-helical structures contributes to the initial stage of membrane damage, while β-sheet structures on the membrane surface are more involved in the later stage of fibril-induced membrane disruption.
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Affiliation(s)
- Qin Qiao
- Digital Medical Research Center, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China.
- Shanghai Key Laboratory of Medical Imaging Computing and Computer Assisted Intervention, Shanghai 200032, China
| | - Guanghong Wei
- Department of Physics, State Key Laboratory of Surface Physics, Key Laboratory for Computational Physical Science (Ministry of Education), Fudan University, Shanghai 200438, China
| | - Zhijian Song
- Digital Medical Research Center, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China.
- Shanghai Key Laboratory of Medical Imaging Computing and Computer Assisted Intervention, Shanghai 200032, China
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2
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Santos N, Segura L, Lewis A, Pham T, Cheng KH. Multiscale Modeling of Macromolecular Interactions between Tau-Amylin Oligomers and Asymmetric Lipid Nanodomains That Link Alzheimer's and Diabetic Diseases. Molecules 2024; 29:740. [PMID: 38338484 PMCID: PMC10856442 DOI: 10.3390/molecules29030740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 01/17/2024] [Accepted: 02/03/2024] [Indexed: 02/12/2024] Open
Abstract
The molecular events of protein misfolding and self-aggregation of tau and amylin are associated with the progression of Alzheimer's and diabetes, respectively. Recent studies suggest that tau and amylin can form hetero-tau-amylin oligomers. Those hetero-oligomers are more neurotoxic than homo-tau oligomers. So far, the detailed interactions between the hetero-oligomers and the neuronal membrane are unknown. Using multiscale MD simulations, the lipid binding and protein folding behaviors of hetero-oligomers on asymmetric lipid nanodomains or raft membranes were examined. Our raft membranes contain phase-separated phosphatidylcholine (PC), cholesterol, and anionic phosphatidylserine (PS) or ganglioside (GM1) in one leaflet of the lipid bilayer. The hetero-oligomers bound more strongly to the PS and GM1 than other lipids via the hydrophobic and hydrophilic interactions, respectively, in the raft membranes. The hetero-tetramer disrupted the acyl chain orders of both PC and PS in the PS-containing raft membrane, but only the GM1 in the GM1-containing raft membrane as effectively as the homo-tau-tetramer. We discovered that the alpha-helical content in the heterodimer was greater than the sum of alpha-helical contents from isolated tau and amylin monomers on both raft membranes, indicative of a synergetic effect of tau-amylin interactions in surface-induced protein folding. Our results provide new molecular insights into understanding the cross-talk between Alzheimer's and diabetes.
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Affiliation(s)
- Natalia Santos
- Neuroscience Department, Trinity University, San Antonio, TX 78212, USA; (N.S.); (L.S.); (A.L.)
| | - Luthary Segura
- Neuroscience Department, Trinity University, San Antonio, TX 78212, USA; (N.S.); (L.S.); (A.L.)
| | - Amber Lewis
- Neuroscience Department, Trinity University, San Antonio, TX 78212, USA; (N.S.); (L.S.); (A.L.)
| | - Thuong Pham
- Physics Department, Trinity University, San Antonio, TX 78212, USA;
| | - Kwan H. Cheng
- Neuroscience Department, Trinity University, San Antonio, TX 78212, USA; (N.S.); (L.S.); (A.L.)
- Physics Department, Trinity University, San Antonio, TX 78212, USA;
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3
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Maurer M, Lazaridis T. Transmembrane β-Barrel Models of α-Synuclein Oligomers. J Chem Inf Model 2023; 63:7171-7179. [PMID: 37963823 DOI: 10.1021/acs.jcim.3c00997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2023]
Abstract
The aggregation of α-synuclein is implicated in a number of neurodegenerative diseases, such as Parkinson's and Multiple System Atrophy, but the role of these aggregates in disease development is not clear. One possible mechanism of cytotoxicity is the disturbance or permeabilization of cell membranes by certain types of oligomers. However, no high-resolution structure of such membrane-embedded complexes has ever been determined. Here we construct and evaluate putative transmembrane β-barrels formed by this protein. Examination of the α-synuclein sequence reveals two regions that could form membrane-embedded β-hairpins: 64-92 (the NAC), and 35-56, which harbors many familial Parkinson's mutations. The stability of β-barrels formed by these hairpins is examined first in implicit membrane pores and then by multimicrosecond all-atom simulations. We find that a NAC region barrel remains stably inserted and hydrated for at least 10 μs. A 35-56 barrel remains stably inserted in the membrane but dehydrates and collapses if all His50 are neutral or if His50 is replaced by Q. If half of the His50 are doubly protonated, the barrel takes an oval shape but remains hydrated for at least 10 μs. Possible implications of these findings for α-synuclein pathology are discussed.
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Affiliation(s)
- Manuela Maurer
- Department of Chemistry & Biochemistry, City College of New York/CUNY, 160 Convent Ave, New York, New York 10031, United States
| | - Themis Lazaridis
- Department of Chemistry & Biochemistry, City College of New York/CUNY, 160 Convent Ave, New York, New York 10031, United States
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4
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Muñoz-Gutiérrez C, Adasme-Carreño F, Alzate-Morales J, Ireta J. Effect of strand register in the stability and reactivity of crystals from peptides forming amyloid fibrils. Phys Chem Chem Phys 2023; 25:23885-23893. [PMID: 37642522 DOI: 10.1039/d3cp01762a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Amyloids are cytotoxic protein aggregates that deposit in human tissues, leading to several health disorders. Their aggregates can also exhibit catalytic properties, and they have been used as candidates for the development of functional biomaterials. Despite being polymorphic, amyloids often assemble as cross-β fibrils formed by in-register β sheet layers. Recent studies of some amyloidogenic protein segments revealed that they crystallize as antiparallel out-of-register β sheets. Such arrangement has been proposed to be responsible for the cytotoxicity in amyloid diseases, however, there is still no consensus on the molecular mechanism. Interestingly, two amyloidogenic peptide segments, NFGAILS and FGAILSS, arrange into out-of-register and in-register β sheets, respectively, even though they solely differ by one aminoacid residue at both termini. In this work, we used density functional theory (DFT) to address how the strand register contributes into the packing and molecular properties of the NFGAILS and FGAILSS crystals. Our results show that the out-of-register structure is substantially more stable, at 0 K, than the in-register one due to stronger inter-strand contacts. Based on an analysis of the electrostatic potential of the crystal slabs, it is suggested that the out-of-register may potentially interact with negatively charged groups, like those found in cell membranes. Moreover, calculated reactivity descriptors indicate a similar outcome, where only the out-of-register peptide exhibits intrinsic reactive surface sites at the exposed amine and carboxylic groups. It is therefore suggested that the out-of-register arrangement may indeed be crucial for amyloid cytotoxicity. The findings presented here could help to further our understanding of amyloid aggregation, function, and toxicity.
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Affiliation(s)
- Camila Muñoz-Gutiérrez
- Centro de Bioinformática, Simulación y Modelado (CBSM), Facultad de Ingeniería, Universidad de Talca, Campus Talca, 1 Poniente No. 1141, Box 721, Talca, Chile
| | - Francisco Adasme-Carreño
- Centro de Investigación de Estudios Avanzados del Maule (CIEAM), Vicerrectoría de Investigación y Postgrado, Universidad Católica del Maule, Talca 3480112, Chile
- Laboratorio de Bioinformática y Química Computacional (LBQC), Departamento de Medicina Traslacional, Facultad de Medicina, Universidad Católica del Maule, Talca 3480112, Chile
| | - Jans Alzate-Morales
- Centro de Bioinformática, Simulación y Modelado (CBSM), Facultad de Ingeniería, Universidad de Talca, Campus Talca, 1 Poniente No. 1141, Box 721, Talca, Chile
| | - Joel Ireta
- Departamento de Química, División de Ciencias Básicas e Ingeniería, Universidad Autónoma Metropolitana-Iztapalapa, A.P. 55-534, Ciudad de México 09340, Mexico.
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5
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Dutta A, Sepehri A, Lazaridis T. Putative Pore Structures of Amyloid β 25-35 in Lipid Bilayers. Biochemistry 2023; 62:2549-2558. [PMID: 37582191 DOI: 10.1021/acs.biochem.3c00323] [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] [Indexed: 08/17/2023]
Abstract
The amyloid β peptide aggregates to form extracellular plaques in the brains of Alzheimer's disease patients. Certain of its fragments have been found to have similar properties to those of the full-length peptide. The best-studied of these is 25-35, which aggregates into fibrils, is toxic to neurons, and forms ion channels in synthetic lipid bilayers. Here, we investigate possible pore-forming structures of oligomers of this peptide in a POPC/POPG membrane. We consider octameric and decameric β-barrels of different topology, strand orientation, and shear, evaluate their stability in an implicit membrane model, and subject the best models to multimicrosecond all-atom molecular dynamics simulations. We find two decameric structures that are kinetically stable in membranes on this time scale: an imperfectly closed antiparallel β-barrel with K28 in the pore lumen and a short parallel β-barrel with K28 toward the membrane interface. Both structures exhibit dehydrated gaps in the pore lumen, which are larger for the antiparallel barrel. Based on these results, the experimental cation selectivity, the dependence of ion channel activity on voltage direction, and certain mutation data, the parallel model seems more compatible with experimental data.
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Affiliation(s)
- Ankita Dutta
- Department of Chemistry, City College of New York/CUNY, 160 Convent Avenue, New York, New York 10031, United States
- Graduate Program in Biochemistry, The Graduate Center, City University of New York, 365 Fifth Avenue, New York, New York 10016, United States
| | - Aliasghar Sepehri
- Department of Chemistry, City College of New York/CUNY, 160 Convent Avenue, New York, New York 10031, United States
| | - Themis Lazaridis
- Department of Chemistry, City College of New York/CUNY, 160 Convent Avenue, New York, New York 10031, United States
- Graduate Programs in Chemistry, Biochemistry, and Physics The Graduate Center, City University of New York, 365 Fifth Avenue, New York, New York 10016, United States
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Nguyen N, Lewis A, Pham T, Sikazwe D, Cheng KH. Exploring the Role of Anionic Lipid Nanodomains in the Membrane Disruption and Protein Folding of Human Islet Amyloid Polypeptide Oligomers on Lipid Membrane Surfaces Using Multiscale Molecular Dynamics Simulations. Molecules 2023; 28:4191. [PMID: 37241931 PMCID: PMC10223233 DOI: 10.3390/molecules28104191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 05/12/2023] [Accepted: 05/16/2023] [Indexed: 05/28/2023] Open
Abstract
The aggregation of human Islet Amyloid Polypeptide (hIAPP) on cell membranes is linked to amyloid diseases. However, the physio-chemical mechanisms of how these hIAPP aggregates trigger membrane damage are unclear. Using coarse-grained and all-atom molecular dynamics simulations, we investigated the role of lipid nanodomains in the presence or absence of anionic lipids, phosphatidylserine (PS), and a ganglioside (GM1), in the membrane disruption and protein folding behaviors of hIAPP aggregates on phase-separated raft membranes. Our raft membranes contain liquid-ordered (Lo), liquid-disordered (Ld), mixed Lo/Ld (Lod), PS-cluster, and GM1-cluster nanosized domains. We observed that hIAPP aggregates bound to the Lod domain in the absence of anionic lipids, but also to the GM1-cluster- and PS-cluster-containing domains, with stronger affinity in the presence of anionic lipids. We discovered that L16 and I26 are the lipid anchoring residues of hIAPP binding to the Lod and PS-cluster domains. Finally, significant lipid acyl chain order disruption in the annular lipid shells surrounding the membrane-bound hIAPP aggregates and protein folding, particularly beta-sheet formation, in larger protein aggregates were evident. We propose that the interactions of hIAPP and both non-anionic and anionic lipid nanodomains represent key molecular events of membrane damage associated with the pathogenesis of amyloid diseases.
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Affiliation(s)
- Ngoc Nguyen
- Physics Department, Trinity University, San Antonio, TX 78212, USA; (N.N.); (T.P.)
| | - Amber Lewis
- Neuroscience Department, Trinity University, San Antonio, TX 78212, USA;
| | - Thuong Pham
- Physics Department, Trinity University, San Antonio, TX 78212, USA; (N.N.); (T.P.)
| | - Donald Sikazwe
- Pharmaceutical Sciences Department, Feik School of Pharmacy, University of the Incarnate Word, San Antonio, TX 78209, USA;
| | - Kwan H. Cheng
- Physics Department, Trinity University, San Antonio, TX 78212, USA; (N.N.); (T.P.)
- Neuroscience Department, Trinity University, San Antonio, TX 78212, USA;
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7
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Lewis A, Pham T, Nguyen N, Graf A, Cheng KH. Lipid domain boundary triggers membrane damage and protein folding of human islet amyloid polypeptide in the early pathogenesis of amyloid diseases. Biophys Chem 2023; 296:106993. [PMID: 36898349 DOI: 10.1016/j.bpc.2023.106993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 02/28/2023] [Accepted: 02/28/2023] [Indexed: 03/06/2023]
Abstract
The misfolding and self-aggregation of human Islet Amyloid Polypeptide (hIAPP) are linked to the onset of type 2 diabetes (T2D). However, the mechanism of how the disordered hIAPP aggregates trigger membrane damage leading to the loss of Islet cells in T2D is unknown. Using coarse-grained (CG) and all-atom (AA) molecular dynamics simulations, we have investigated the membrane-disruption behaviors of hIAPP oligomers on the phase-separated lipid nanodomains that mimic the highly heterogeneous lipid raft structures of cell membranes. Our results revealed that hIAPP oligomers preferentially bind to the liquid-ordered and liquid-disordered domain boundary around two hydrophobic residues at L16 and I26, and lipid acyl chain order disruption and beta-sheet formation occur upon hIAPP binding to the membrane surface. We propose that the lipid order disruption and surface-induced beta-sheet formation on the lipid domain boundary represent the early molecular events of membrane damage associated with the early pathogenesis of T2D.
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Affiliation(s)
- Amber Lewis
- Neuroscience Dept., Trinity University, San Antonio, TX, USA
| | - Thuong Pham
- Physics Dept., Trinity University, San Antonio, TX, USA
| | - Ngoc Nguyen
- Physics Dept., Trinity University, San Antonio, TX, USA
| | - Angela Graf
- Physics Dept., Trinity University, San Antonio, TX, USA
| | - Kwan H Cheng
- Neuroscience Dept., Trinity University, San Antonio, TX, USA; Physics Dept., Trinity University, San Antonio, TX, USA.
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8
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Abstract
Perturbation of cell membranes by amyloid β (Ab) peptide oligomers is one possible mechanism of cytotoxicity in Alzheimer's disease, but the structure of such Ab-membrane complexes is unknown. Here we examine the stability of several putative structures by implicit membrane and all-atom molecular dynamics simulations. The structures include (a) a variety of models proposed by other researchers in the past, (b) a heptameric β barrel determined by grafting the Ab sequence onto α-hemolysin, (c) a similar structure with modified strand orientation and turn location based on an experimental β-hairpin structure, (d) oligomers inserting C-terminal β hairpins into one leaflet of the bilayer, (e) oligomers forming parallel C-terminal β barrels, and (f) a helical hexamer made of C-terminal fragments. The α-hemolysin-grafted structure and its alternately oriented variant are stable in the membrane and form an aqueous pore. In contrast, the C-terminal parallel barrels are not stable, presumably due to excessive hydrophobicity of their inner surface. The helical hexamer also failed to stabilize an aqueous pore for the same reason. The C-terminal hairpin-inserting structures remain stably inserted but, again, do not form an aqueous pore. Our results suggest that only β-barrels inserting a combination of C-terminal and other residues can form stable aqueous pores.
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Affiliation(s)
- Aliasghar Sepehri
- Department of Chemistry, City College of New York, CUNY, 160 Convent Avenue, New York, New York10031, United States
| | - Themis Lazaridis
- Department of Chemistry, City College of New York, CUNY, 160 Convent Avenue, New York, New York10031, United States.,Graduate Programs in Chemistry, Biochemistry, and Physics, The Graduate Center, City University of New York, 365 Fifth Avenue, New York, New York10016, United States
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9
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Khemtemourian L, Fatafta H, Davion B, Lecomte S, Castano S, Strodel B. Structural Dissection of the First Events Following Membrane Binding of the Islet Amyloid Polypeptide. Front Mol Biosci 2022; 9:849979. [PMID: 35372496 PMCID: PMC8965455 DOI: 10.3389/fmolb.2022.849979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 02/18/2022] [Indexed: 11/13/2022] Open
Abstract
The islet amyloid polypeptide (IAPP) is the main constituent of the amyloid fibrils found in the pancreas of type 2 diabetes patients. The aggregation of IAPP is known to cause cell death, where the cell membrane plays a dual role: being a catalyst of IAPP aggregation and being the target of IAPP toxicity. Using ATR-FTIR spectroscopy, transmission electron microscopy, and molecular dynamics simulations we investigate the very first molecular steps following IAPP binding to a lipid membrane. In particular, we assess the combined effects of the charge state of amino-acid residue 18 and the IAPP-membrane interactions on the structures of monomeric and aggregated IAPP. Distinct IAPP-membrane interaction modes for the various IAPP variants are revealed. Membrane binding causes IAPP to fold into an amphipathic α-helix, which in the case of H18K-, and H18R-IAPP readily moves beyond the headgroup region. For all IAPP variants but H18E-IAPP, the membrane-bound helix is an intermediate on the way to amyloid aggregation, while H18E-IAPP remains in a stable helical conformation. The fibrillar aggregates of wild-type IAPP and H18K-IAPP are dominated by an antiparallel β-sheet conformation, while H18R- and H18A-IAPP exhibit both antiparallel and parallel β-sheets as well as amorphous aggregates. Our results emphasize the decisive role of residue 18 for the structure and membrane interaction of IAPP. This residue is thus a good therapeutic target for destabilizing membrane-bound IAPP fibrils to inhibit their toxic actions.
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Affiliation(s)
- Lucie Khemtemourian
- Université de Bordeaux, CNRS, Bordeaux IMP, CBMN, Pessac, France
- *Correspondence: Lucie Khemtemourian, ; Birgit Strodel,
| | - Hebah Fatafta
- Institute of Biological Information Processing, Structural Biochemistry, Jülich, Germany
- JuStruct, Jülich Center for Structural Biology, Jülich, Germany
| | - Benoit Davion
- Université de Bordeaux, CNRS, Bordeaux IMP, CBMN, Pessac, France
| | - Sophie Lecomte
- Université de Bordeaux, CNRS, Bordeaux IMP, CBMN, Pessac, France
| | - Sabine Castano
- Université de Bordeaux, CNRS, Bordeaux IMP, CBMN, Pessac, France
| | - Birgit Strodel
- Institute of Biological Information Processing, Structural Biochemistry, Jülich, Germany
- JuStruct, Jülich Center for Structural Biology, Jülich, Germany
- Institute of Theoretical and Computational Chemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- *Correspondence: Lucie Khemtemourian, ; Birgit Strodel,
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Sulatskaya AI, Kosolapova AO, Bobylev AG, Belousov MV, Antonets KS, Sulatsky MI, Kuznetsova IM, Turoverov KK, Stepanenko OV, Nizhnikov AA. β-Barrels and Amyloids: Structural Transitions, Biological Functions, and Pathogenesis. Int J Mol Sci 2021; 22:11316. [PMID: 34768745 PMCID: PMC8582884 DOI: 10.3390/ijms222111316] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 10/15/2021] [Accepted: 10/18/2021] [Indexed: 01/17/2023] Open
Abstract
Insoluble protein aggregates with fibrillar morphology called amyloids and β-barrel proteins both share a β-sheet-rich structure. Correctly folded β-barrel proteins can not only function in monomeric (dimeric) form, but also tend to interact with one another-followed, in several cases, by formation of higher order oligomers or even aggregates. In recent years, findings proving that β-barrel proteins can adopt cross-β amyloid folds have emerged. Different β-barrel proteins were shown to form amyloid fibrils in vitro. The formation of functional amyloids in vivo by β-barrel proteins for which the amyloid state is native was also discovered. In particular, several prokaryotic and eukaryotic proteins with β-barrel domains were demonstrated to form amyloids in vivo, where they participate in interspecies interactions and nutrient storage, respectively. According to recent observations, despite the variety of primary structures of amyloid-forming proteins, most of them can adopt a conformational state with the β-barrel topology. This state can be intermediate on the pathway of fibrillogenesis ("on-pathway state"), or can be formed as a result of an alternative assembly of partially unfolded monomers ("off-pathway state"). The β-barrel oligomers formed by amyloid proteins possess toxicity, and are likely to be involved in the development of amyloidoses, thus representing promising targets for potential therapy of these incurable diseases. Considering rapidly growing discoveries of the amyloid-forming β-barrels, we may suggest that their real number and diversity of functions are significantly higher than identified to date, and represent only "the tip of the iceberg". Here, we summarize the data on the amyloid-forming β-barrel proteins, their physicochemical properties, and their biological functions, and discuss probable means and consequences of the amyloidogenesis of these proteins, along with structural relationships between these two widespread types of β-folds.
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Affiliation(s)
- Anna I. Sulatskaya
- Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology, 3 Podbelskogo Sh., Pushkin, 196608 St. Petersburg, Russia; (A.I.S.); (A.O.K.); (M.V.B.); (K.S.A.)
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky Av., 194064 St. Petersburg, Russia; (I.M.K.); (K.K.T.); (O.V.S.)
| | - Anastasiia O. Kosolapova
- Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology, 3 Podbelskogo Sh., Pushkin, 196608 St. Petersburg, Russia; (A.I.S.); (A.O.K.); (M.V.B.); (K.S.A.)
- Faculty of Biology, St. Petersburg State University, 7/9 Universitetskaya Emb., 199034 St. Petersburg, Russia
| | - Alexander G. Bobylev
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, 3 Institutskaya St., 142290 Moscow, Russia;
| | - Mikhail V. Belousov
- Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology, 3 Podbelskogo Sh., Pushkin, 196608 St. Petersburg, Russia; (A.I.S.); (A.O.K.); (M.V.B.); (K.S.A.)
- Faculty of Biology, St. Petersburg State University, 7/9 Universitetskaya Emb., 199034 St. Petersburg, Russia
| | - Kirill S. Antonets
- Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology, 3 Podbelskogo Sh., Pushkin, 196608 St. Petersburg, Russia; (A.I.S.); (A.O.K.); (M.V.B.); (K.S.A.)
- Faculty of Biology, St. Petersburg State University, 7/9 Universitetskaya Emb., 199034 St. Petersburg, Russia
| | - Maksim I. Sulatsky
- Laboratory of Cell Morphology, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky Av., 194064 St. Petersburg, Russia;
| | - Irina M. Kuznetsova
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky Av., 194064 St. Petersburg, Russia; (I.M.K.); (K.K.T.); (O.V.S.)
| | - Konstantin K. Turoverov
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky Av., 194064 St. Petersburg, Russia; (I.M.K.); (K.K.T.); (O.V.S.)
| | - Olesya V. Stepanenko
- Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, 4 Tikhoretsky Av., 194064 St. Petersburg, Russia; (I.M.K.); (K.K.T.); (O.V.S.)
| | - Anton A. Nizhnikov
- Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology, 3 Podbelskogo Sh., Pushkin, 196608 St. Petersburg, Russia; (A.I.S.); (A.O.K.); (M.V.B.); (K.S.A.)
- Faculty of Biology, St. Petersburg State University, 7/9 Universitetskaya Emb., 199034 St. Petersburg, Russia
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