51
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Induction of amyloidogenicity in wild type HEWL by a dialdehyde: Analysis involving multi dimensional approach. Int J Biol Macromol 2014; 64:36-44. [DOI: 10.1016/j.ijbiomac.2013.11.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Revised: 11/17/2013] [Accepted: 11/18/2013] [Indexed: 11/23/2022]
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52
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Michaels TCT, Buell AK, Terentjev EM, Knowles TPJ. Quantitative Analysis of Diffusive Reactions at the Solid-Liquid Interface in Finite Systems. J Phys Chem Lett 2014; 5:695-699. [PMID: 26270839 DOI: 10.1021/jz4024833] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A central element in many processes in physics, chemistry and biology is a reaction between a species immobilized on a surface and a partner that is able to diffuse in solution. However, integrated rate laws for this class of chemical processes have so far only been found in certain special cases. Here, we present a model for the time dependence of an irreversible reaction between particles in a solution of finite volume and a surface. The resulting analytical expression allows quantitative analysis of the transient kinetics of the reaction between soluble particles and a surface. We apply this approach to the analysis of quartz crystal microbalance experiments of protein aggregation under conditions where both reaction and diffusion define the overall kinetics. Furthermore, we use the model to determine absolute mass sensitivity coefficients for soft and rough surfaces, a situation where conventional approaches to determine the mass sensitivity a priori fail.
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Affiliation(s)
- Thomas C T Michaels
- †Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Alexander K Buell
- †Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Eugene M Terentjev
- ‡Cavendish Laboratory, University of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Tuomas P J Knowles
- †Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
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53
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Chen T, Chan HS. Effects of desolvation barriers and sidechains on local–nonlocal coupling and chevron behaviors in coarse-grained models of protein folding. Phys Chem Chem Phys 2014; 16:6460-79. [DOI: 10.1039/c3cp54866j] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Coarse-grained protein chain models with desolvation barriers or sidechains lead to stronger local–nonlocal coupling and more linear chevron plots.
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Affiliation(s)
- Tao Chen
- Departments of Biochemistry
- of Molecular Genetics
- of Physics
- University of Toronto
- Toronto, Canada
| | - Hue Sun Chan
- Departments of Biochemistry
- of Molecular Genetics
- of Physics
- University of Toronto
- Toronto, Canada
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54
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In vitro hyperglycemic condition facilitated the aggregation of lysozyme via the passage through a molten globule state. Cell Biochem Biophys 2013. [PMID: 23184703 DOI: 10.1007/s12013-012-9479-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Hyperglycemic condition i.e. an increase in blood glucose concentration has been linked to bring about structural alterations in the native state of proteins. Glucose concentrations of 50 and 100 mM in vitro, which correspond to hyperglycemic condition, were tested to investigate their effect on lysozyme native structure. Incubating enzyme with 50 and 100 mM glucose for a period of 7 days, an intermediate state on day 4 and 3 was observed, respectively. The presence of intermediate state was characterized by a 22 % increase in the intrinsic fluorescence intensity with a red shift of 20 nm compared to the native state, a 5 % increase in ANS-fluorescence intensity relative to the native due to the surfacing of hydrophobic clusters and a sharp decrease in near-UV CD signal at around 284 and 291 nm. The state retains substantial native-like secondary structure. This partially unfolded intermediate state can be referred as 'molten globule', which finally tends to aggregate on day 6 and 4 with 50 and 100 mM glucose concentration, respectively, as a result of cross-linking between lysozyme molecules. The aggregates were confirmed by the presence of β-sheet structure as depicted by far-UV CD, an increase in ThT fluorescence as well as the fibrillar morphology shown by SEM. Moreover, advanced glycation end products were also accompanied as the emission peak was observed at 460 and 470 nm corresponding to the formation of pentosidine and malonaldehyde, respectively.
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55
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De Genst E, Chan PH, Pardon E, Hsu STD, Kumita JR, Christodoulou J, Menzer L, Chirgadze DY, Robinson CV, Muyldermans S, Matagne A, Wyns L, Dobson CM, Dumoulin M. A nanobody binding to non-amyloidogenic regions of the protein human lysozyme enhances partial unfolding but inhibits amyloid fibril formation. J Phys Chem B 2013; 117:13245-13258. [PMID: 23919586 PMCID: PMC4612432 DOI: 10.1021/jp403425z] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
We report the effects of the interaction of two camelid antibody fragments, generally called nanobodies, namely cAb-HuL5 and a stabilized and more aggregation-resistant variant cAb-HuL5G obtained by protein engineering, on the properties of two amyloidogenic variants of human lysozyme, I56T and D67H, whose deposition in vital organs including the liver, kidney, and spleen is associated with a familial non-neuropathic systemic amyloidosis. Both NMR spectroscopy and X-ray crystallographic studies reveal that cAb-HuL5 binds to the α-domain, one of the two lobes of the native lysozyme structure. The binding of cAb-HuL5/cAb-HuL5G strongly inhibits fibril formation by the amyloidogenic variants; it does not, however, suppress the locally transient cooperative unfolding transitions, characteristic of these variants, in which the β-domain and the C-helix unfold and which represents key early intermediate species in the formation of amyloid fibrils. Therefore, unlike two other nanobodies previously described, cAb-HuL5/cAb-HuL5G does not inhibit fibril formation via the restoration of the global cooperativity of the native structure of the lysozyme variants to that characteristic of the wild-type protein. Instead, it inhibits a subsequent step in the assembly of the fibrils, involving the unfolding and structural reorganization of the α-domain. These results show that nanobodies can protect against the formation of pathogenic aggregates at different stages in the structural transition of a protein from the soluble native state into amyloid fibrils, illustrating their value as structural probes to study the molecular mechanisms of amyloid fibril formation. Combined with their amenability to protein engineering techniques to improve their stability and solubility, these findings support the suggestion that nanobodies can potentially be developed as therapeutics to combat protein misfolding diseases.
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Affiliation(s)
- Erwin De Genst
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K
| | - Pak-Ho Chan
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K
- State Key Laboratory of Chirosciences, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P.R. China
| | - Els Pardon
- Department of Structural Biology, Vlaams Interuniversitair Instituut voor Biotechnologie VIB, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
- Laboratory of Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
| | - Shang-Te D. Hsu
- Institute of Bioinformatics and Structural Biology, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu, 30013, Taiwan
- Institute of Biological Chemistry, Academia Sinica, No 128, Section 2, Academia Road, Taipei 11529, Taiwan
- Institute of Biochemical Sciences, National Taiwan University, No 1, Section 4, Roosevelt Road, Taipei 10617, Taiwan
| | - Janet R. Kumita
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K
| | - John Christodoulou
- Institute of Structural and Molecular Biology, University College London and Birkbeck College, Gower Street, London WC1E 6BT, U.K
| | - Linda Menzer
- Laboratory of Enzymology and Protein Folding, Centre for Protein Engineering, Institute of Chemistry, University of Liege, B-4000 Liege (Sart Tilman), Belgium
| | - Dimitri Y. Chirgadze
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, U.K
| | - Carol V. Robinson
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3QZ, U.K
| | - Serge Muyldermans
- Department of Structural Biology, Vlaams Interuniversitair Instituut voor Biotechnologie VIB, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
- Research Unit of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
| | - André Matagne
- Laboratory of Enzymology and Protein Folding, Centre for Protein Engineering, Institute of Chemistry, University of Liege, B-4000 Liege (Sart Tilman), Belgium
| | - Lode Wyns
- Department of Structural Biology, Vlaams Interuniversitair Instituut voor Biotechnologie VIB, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
- Laboratory of Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
| | - Christopher M. Dobson
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K
| | - Mireille Dumoulin
- Laboratory of Enzymology and Protein Folding, Centre for Protein Engineering, Institute of Chemistry, University of Liege, B-4000 Liege (Sart Tilman), Belgium
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56
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Coelho-Cerqueira E, Carmo-Gonçalves P, Sá Pinheiro A, Cortines J, Follmer C. α-Synuclein as an intrinsically disordered monomer - fact or artefact? FEBS J 2013; 280:4915-27. [DOI: 10.1111/febs.12471] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Revised: 07/12/2013] [Accepted: 07/31/2013] [Indexed: 11/28/2022]
Affiliation(s)
- Eduardo Coelho-Cerqueira
- Department of Physical Chemistry; Institute of Chemistry; Federal University of Rio de Janeiro; Brazil
| | - Phelippe Carmo-Gonçalves
- Department of Physical Chemistry; Institute of Chemistry; Federal University of Rio de Janeiro; Brazil
| | - Anderson Sá Pinheiro
- Department of Biochemistry; Institute of Chemistry; Federal University of Rio de Janeiro; Brazil
| | - Juliana Cortines
- Department of Virology; Institute of Microbiology Paulo de Góes; Federal University of Rio de Janeiro; Brazil
| | - Cristian Follmer
- Department of Physical Chemistry; Institute of Chemistry; Federal University of Rio de Janeiro; Brazil
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57
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Electrostatic effects in filamentous protein aggregation. Biophys J 2013; 104:1116-26. [PMID: 23473495 DOI: 10.1016/j.bpj.2013.01.031] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Revised: 01/06/2013] [Accepted: 01/22/2013] [Indexed: 11/21/2022] Open
Abstract
Electrostatic forces play a key role in mediating interactions between proteins. However, gaining quantitative insights into the complex effects of electrostatics on protein behavior has proved challenging, due to the wide palette of scenarios through which both cations and anions can interact with polypeptide molecules in a specific manner or can result in screening in solution. In this article, we have used a variety of biophysical methods to probe the steady-state kinetics of fibrillar protein self-assembly in a highly quantitative manner to detect how it is modulated by changes in solution ionic strength. Due to the exponential modulation of the reaction rate by electrostatic forces, this reaction represents an exquisitely sensitive probe of these effects in protein-protein interactions. Our approach, which involves a combination of experimental kinetic measurements and theoretical analysis, reveals a hierarchy of electrostatic effects that control protein aggregation. Furthermore, our results provide a highly sensitive method for the estimation of the magnitude of binding of a variety of ions to protein molecules.
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58
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Mechanism of protein kinetic stabilization by engineered disulfide crosslinks. PLoS One 2013; 8:e70013. [PMID: 23936134 PMCID: PMC3728334 DOI: 10.1371/journal.pone.0070013] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2013] [Accepted: 06/14/2013] [Indexed: 11/20/2022] Open
Abstract
The impact of disulfide bonds on protein stability goes beyond simple equilibrium thermodynamics effects associated with the conformational entropy of the unfolded state. Indeed, disulfide crosslinks may play a role in the prevention of dysfunctional association and strongly affect the rates of irreversible enzyme inactivation, highly relevant in biotechnological applications. While these kinetic-stability effects remain poorly understood, by analogy with proposed mechanisms for processes of protein aggregation and fibrillogenesis, we propose that they may be determined by the properties of sparsely-populated, partially-unfolded intermediates. Here we report the successful design, on the basis of high temperature molecular-dynamics simulations, of six thermodynamically and kinetically stabilized variants of phytase from Citrobacter braakii (a biotechnologically important enzyme) with one, two or three engineered disulfides. Activity measurements and 3D crystal structure determination demonstrate that the engineered crosslinks do not cause dramatic alterations in the native structure. The inactivation kinetics for all the variants displays a strongly non-Arrhenius temperature dependence, with the time-scale for the irreversible denaturation process reaching a minimum at a given temperature within the range of the denaturation transition. We show this striking feature to be a signature of a key role played by a partially unfolded, intermediate state/ensemble. Energetic and mutational analyses confirm that the intermediate is highly unfolded (akin to a proposed critical intermediate in the misfolding of the prion protein), a result that explains the observed kinetic stabilization. Our results provide a rationale for the kinetic-stability consequences of disulfide-crosslink engineering and an experimental methodology to arrive at energetic/structural descriptions of the sparsely populated and elusive intermediates that play key roles in irreversible protein denaturation.
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59
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Brogan APS, Sharma KP, Perriman AW, Mann S. Isolation of a highly reactive β-sheet-rich intermediate of lysozyme in a solvent-free liquid phase. J Phys Chem B 2013; 117:8400-7. [PMID: 23790147 DOI: 10.1021/jp4041524] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The thermal denaturation of solvent-free liquid lysozyme at temperatures in excess of 200 °C was studied by synchrotron radiation circular dichroism spectroscopy. Temperature-dependent changes in the secondary structure were used to map the equilibrium denaturation pathway and characterize a reactive β-sheet-rich unfolding intermediate that was stable in the solvent-free liquid phase under anhydrous conditions but which underwent irreversible aggregation in the presence of water. The unfolding intermediate had a transition temperature of 78 °C and was extremely stable to temperature, eventually reaching the fully denatured state at 178 °C. We propose that the three-stage denaturation pathway arises from the decreased stability of the native state due to the absence of any appreciable hydrophobic effect, along with an entropically derived stabilization of the reactive intermediate associated with molecular crowding in the solvent-free liquid.
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Affiliation(s)
- Alex P S Brogan
- Centre for Organized Matter Chemistry, School of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom
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60
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Koroleva ON, Dubrovin EV, Khodak YA, Kuzmina NV, Yaminsky IV, Drutsa VL. The model of amyloid aggregation of Escherichia coli RNA polymerase σ70 subunit based on AFM data and in vitro assays. Cell Biochem Biophys 2013; 66:623-36. [PMID: 23306967 DOI: 10.1007/s12013-012-9507-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
To propose a model for recently described amyloid aggregation of E.coli RNA polymerase σ(70) subunit, we have investigated the role of its N-terminal region. For this purpose, three mutant variants of protein with deletions Δ1-73, Δ1-100 and Δ74-100 were constructed and studied in a series of in vitro assays and using atomic force microscopy (AFM). Specifically, all RNA polymerase holoenzymes, reconstituted with the use of mutant σ subunits, have shown reduced affinity for promoter-containing DNA and reduced activity in run-off transcription experiments (compared to that of WT species), thus substantiating the modern concept on the modulatory role of N-terminus in formation of open complex and transcription initiation. The ability of mutant proteins to form amyloid-like structures has been investigated using AFM, which revealed the increased propensity of mutant proteins to form rodlike aggregates with the effect being more pronounced for the mutant with the deletion Δ1-73 (10 fold increase). σ(70) subunit aggregation ability has shown complex dependence on the ionic surrounding, which we explain by Debye screening effect and the change of the internal state of the protein. Basing on the obtained data, we propose the model of amyloid fibril formation by σ(70) subunit, implying the involvement of N-terminal region according to the domain swapping mechanism.
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Affiliation(s)
- Olga N Koroleva
- Faculty of Chemistry, Lomonosov Moscow State University, Moscow, Russian Federation
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61
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Raccosta S, Martorana V, Manno M. Thermodynamic versus conformational metastability in fibril-forming lysozyme solutions. J Phys Chem B 2012; 116:12078-87. [PMID: 22984801 DOI: 10.1021/jp303430g] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The role of intermolecular interaction in fibril-forming protein solutions and its relation with molecular conformation is a crucial aspect for the control and inhibition of amyloid structures. Here, we study the fibril formation and the protein-protein interactions of lysozyme at acidic pH and low ionic strength. The amyloid formation occurs after a long lag time and is preceded by the formation of oligomers, which seems to be off-pathway with respect to fibrillation. By measuring the osmotic isothermal compressibility and the collective diffusion coefficient of lysozyme in solution, we observe that the monomeric solution is kept in a thermodynamically metastable state by strong electrostatic repulsion, even in denaturing conditions. The measured repulsive interaction between monomers is satisfactorily accounted for by classical polyelectrolyte theory. Further, we observe a slow conformational change involving both secondary and tertiary structure, which drives the proteins toward a more hydrophobic conformation. Denatured proteins are driven out of metastability through conformational substates, which are kinetically populated and experience a lower activation energy for fibril formation. Thus, our results highlight the role of electrostatic repulsion, which hinders the aggregation of partially denatured proteins and operates as a gatekeeper favoring the association of those monomers whose conformation is capable of forming amyloid structure.
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Affiliation(s)
- Samuele Raccosta
- Institute of Biophysics, National Research Council of Italy, via U. La Malfa 153, I-90146 Palermo, Italy
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62
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A zinc complex of heparan sulfate destabilises lysozyme and alters its conformation. Biochem Biophys Res Commun 2012; 425:794-9. [PMID: 22884801 DOI: 10.1016/j.bbrc.2012.07.154] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Accepted: 07/27/2012] [Indexed: 11/22/2022]
Abstract
The naturally occurring anionic cell surface polysaccharide heparan sulfate is involved in key biological activities and is implicated in amyloid formation. Following addition of Zn-heparan sulfate, hen lysozyme, a model amyloid forming protein, resembled β-rich amyloid by far UV circular dichroism (increased β-sheet: +25%), with a significantly reduced melting temperature (from 68 to 58 °C) by fluorescence shift assay. Secondary structure stability of the Zn-heparan sulfate complex with lysozyme was also distinct from that with heparan sulfate, under stronger denaturation conditions using synchrotron radiation circular dichroism. Changing the cation associated with heparan sulfate is sufficient to alter the conformation and stability of complexes formed between heparan sulfate and lysozyme, substantially reducing the stability of the protein. Complexes of heparan sulfate and cations, such as Zn, which are abundant in the brain, may provide alternative folding routes for proteins.
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63
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Arosio P, Jaquet B, Wu H, Morbidelli M. On the role of salt type and concentration on the stability behavior of a monoclonal antibody solution. Biophys Chem 2012; 168-169:19-27. [DOI: 10.1016/j.bpc.2012.05.004] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 05/23/2012] [Accepted: 05/25/2012] [Indexed: 11/27/2022]
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64
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Buell AK, Dhulesia A, White DA, Knowles TPJ, Dobson CM, Welland ME. Detailed Analysis of the Energy Barriers for Amyloid Fibril Growth. Angew Chem Int Ed Engl 2012; 51:5247-51. [DOI: 10.1002/anie.201108040] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Revised: 01/13/2012] [Indexed: 12/24/2022]
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65
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Buell AK, Dhulesia A, White DA, Knowles TPJ, Dobson CM, Welland ME. Analyse der Energiebarrieren für das Wachstum von Amyloidfibrillen. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201108040] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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66
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Shi H, Pierson NA, Valentine SJ, Clemmer DE. Conformation types of ubiquitin [M+8H]8+ Ions from water:methanol solutions: evidence for the N and A States in aqueous solution. J Phys Chem B 2012; 116:3344-52. [PMID: 22315998 PMCID: PMC3351143 DOI: 10.1021/jp210797x] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Ion mobility and mass spectrometry measurements are used to examine the gas-phase populations of [M+8H](8+) ubiquitin ions formed upon electrospraying 20 different solutions from 100:0 to 5:95 water:methanol that are maintained at pH = 2.0. Over this range of solution conditions, mobility distributions for the +8 charge state show substantial variations. Here we develop a model that treats the combined measurements as one data set. By varying the relative abundances of a discrete set of conformation types, it is possible to represent distributions obtained from any solution. For solutions that favor the well-known A-state ubiquitin, it is possible to represent the gas-phase distributions with seven conformation types. Aqueous conditions that favor the native structure require four more structural types to represent the distribution. This analysis provides the first direct evidence for trace amounts of the A state under native conditions. The method of analysis presented here should help illuminate how solution populations evolve into new gas-phase structures as solvent is removed. Evidence for trace quantities of previously unknown states under native solution conditions may provide insight about the relationship of dynamics to protein function as well as misfolding and aggregation phenomena.
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Affiliation(s)
- Huilin Shi
- Department of Chemistry, Indiana University, 800 Kirkwood Ave. Bloomington, IN 47405
| | - Nicholas A. Pierson
- Department of Chemistry, Indiana University, 800 Kirkwood Ave. Bloomington, IN 47405
| | - Stephen J. Valentine
- Department of Chemistry, Indiana University, 800 Kirkwood Ave. Bloomington, IN 47405
| | - David E. Clemmer
- Department of Chemistry, Indiana University, 800 Kirkwood Ave. Bloomington, IN 47405
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