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Mandal P, Molla AR. Solvent Perturbation of Protein Structures - A Review Study with Lectins. Protein Pept Lett 2020; 27:538-550. [PMID: 31682206 DOI: 10.2174/0929866526666191104145511] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 08/05/2019] [Accepted: 08/07/2019] [Indexed: 01/07/2023]
Abstract
Use of organic molecules as co-solvent with water, the ubiquitous biological solvent, to perturb the structure of proteins is popular in the research area of protein structure and folding. These organic co-solvents are believed to somehow mimic the environment near the cell membrane. Apart from that they induce non-native states which can be present in the protein folding pathway or those states also may be representative of the off pathway structures leading to amyloid formation, responsible for various fatal diseases. In this review, we shall focus on organic co-solvent induced structure perturbation of various members of lectin family. Lectins are excellent model systems for protein folding study because of its wide occurrence, diverse structure and versatile biological functions. Lectins were mainly perturbed by two fluoroalcohols - 2,2,2- trifluoroethanol and 1,1,1,3,3,3-hexafluoroisopropanol whereas glycerol, ethylene glycol and polyethylene glycols were used in some cases. Overall, all native lectins were denatured by alcohols and most of the denatured lectins have predominant helical secondary structure. But characterization of the helical states and the transition pathway for various lectins revealed diverse result.
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Affiliation(s)
- Pritha Mandal
- Department of Chemistry, Krishnagar Government College, Krishnagar, West Bengal-741101, India
| | - Anisur R Molla
- Department of Chemistry, Bidhannagar College, Salt Lake, Kolkata -700 064, India
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2
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Niu B, Mackness BC, Zitzewitz JA, Matthews CR, Gross ML. Trifluoroethanol Partially Unfolds G93A SOD1 Leading to Protein Aggregation: A Study by Native Mass Spectrometry and FPOP Protein Footprinting. Biochemistry 2020; 59:3650-3659. [PMID: 32924445 DOI: 10.1021/acs.biochem.0c00425] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Misfolding of Cu, Zn superoxide dismutase (SOD1) variants may lead to protein aggregation and ultimately amyotrophic lateral sclerosis (ALS). The mechanism and protein conformational changes during this process are complex and remain unclear. To study SOD1 variant aggregation at the molecular level and in solution, we chemically induced aggregation of a mutant variant (G93A SOD1) with trifluoroethanol (TFE) and used both native mass spectrometry (MS) to analyze the intact protein and fast photochemical oxidation of proteins (FPOP) to characterize the structural changes induced by TFE. We found partially unfolded G93A SOD1 monomers prior to oligomerization and identified regions of the N-terminus, C-terminus, and strands β5, β6 accountable for the partial unfolding. We propose that exposure of hydrophobic interfaces of these unstructured regions serves as a precursor to aggregation. Our results provide a possible mechanism and molecular basis for ALS-linked SOD1 misfolding and aggregation.
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Affiliation(s)
- Ben Niu
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Brian C Mackness
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, United States
| | - Jill A Zitzewitz
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, United States
| | - C Robert Matthews
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, United States
| | - Michael L Gross
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri 63130, United States
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3
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Hasan S, Isar M, Naeem A. Macromolecular crowding stabilises native structure of α-chymotrypsinogen-A against hexafluoropropanol-induced aggregates. Int J Biol Macromol 2020; 164:3780-3788. [PMID: 32835802 DOI: 10.1016/j.ijbiomac.2020.08.149] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Revised: 08/06/2020] [Accepted: 08/19/2020] [Indexed: 12/20/2022]
Abstract
Cell interior is extremely congested with tightly packed biological macromolecules that exerts macromolecular crowding effect, influencing biophysical properties of proteins. To have a deeper insight into it we studied consequences of crowding on aggregation susceptibility and structural stability of α-chymotrypsinogen-A, pro-enzyme of serine protease family, upon addition of co-solvent reported to exert stress on polypeptides crafting favourable conditions for aggregation. Hexafluoropropan-2-ol (HFIP), a fluorinated alcohol caused structural disruption at 5% v/v unveiled by reduced intrinsic intensity and blue shifted ANS spectra. Significantly enhanced, red-shifted ThT and Congo red spectra sustained conformational changes concomitant with aggregation. FTIR and CD results confirmed transition of native structure to non-native extended, cross-linked beta-sheets. Transmission electron micrographs visibly exhibited incidence of amorphous aggregates. Macromolecular crowding, typically mimicked by concentrated solutions of dextran 70, was noticeably witnessed to defend conformational stability under denaturing condition. The native structure was retained maximally in presence of 100 mg/ml followed by 200 and 300 mg/ml dextran indicating concentration dependent deceleration of aggregate formation. It can be established that explicit consideration of crowding effects using relevant range of inert crowding agents must be a requisite for presumptions on intracellular conformational behaviour of proteins deduced from in vitro experiments.
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Affiliation(s)
- Samra Hasan
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, 202002, U.P., India
| | - Mohd Isar
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, 202002, U.P., India
| | - Aabgeena Naeem
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, 202002, U.P., India.
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4
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Barnes BE, Jenkins TA, Stein LM, Mathers RT, Wicaksana M, Pasquinelli MA, Savin DA. Synthesis and Characterization of a Leucine-Based Block Co-Polypeptide: The Effect of the Leucine Zipper on Self-Assembly. Biomacromolecules 2020; 21:2463-2472. [PMID: 32378896 DOI: 10.1021/acs.biomac.0c00420] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The self-assembly behavior of an ABC triblock copolypeptide consisting of poly(ethylene oxide-b-(leucine-s-valine)-b-lysine) (PEO-PLV-PK) was examined via dynamic light scattering in dilute aqueous solution. Leucine is a hydrophobic, α-helix forming polypeptide that exhibits a "zipper effect" in coiled-coil dimers. We hypothesize that the specific interaction afforded by the leucine zipper dominates the thermodynamics of self-assembly through the side-by-side ordering of α-helices, which drives vesicle formation in a polymer with only 6 wt % hydrophobic content. Additionally, a multitude of assembly sizes and morphologies were attainable from a single polymer, depending on the solution processing method. Thermodynamic effects of the leucine zipper can be interpreted, in part, from solubility parameters determined from molecular modeling. The combination of synthesis, solvent processing, and computational studies helps to elucidate the thermodynamic effects of this unique assembly motif on classical self-assembly processes.
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Affiliation(s)
- Brooke E Barnes
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Taylor A Jenkins
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Lauren M Stein
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Robert T Mathers
- Department of Chemistry, The Pennsylvania State University, New Kensington, Pennsylvania 15068, United States
| | - Masita Wicaksana
- William G. Enloe Magnet High School, 128 Clarendon Crescent, Raleigh, North Carolina 27610, United States
| | - Melissa A Pasquinelli
- Fiber and Polymer Science Program, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Daniel A Savin
- George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
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5
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Effective suppression of the modified PHF6 peptide/1N4R Tau amyloid aggregation by intact curcumin, not its degradation products: Another evidence for the pigment as preventive/therapeutic “functional food”. Int J Biol Macromol 2018; 120:1009-1022. [DOI: 10.1016/j.ijbiomac.2018.08.175] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 08/27/2018] [Accepted: 08/28/2018] [Indexed: 11/24/2022]
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6
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Kumar V, Prakash A, Lynn AM. Alterations in local stability and dynamics of A4V SOD1 in the presence of trifluoroethanol. Biopolymers 2018; 109:e23102. [DOI: 10.1002/bip.23102] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 12/26/2017] [Accepted: 01/03/2018] [Indexed: 12/13/2022]
Affiliation(s)
- Vijay Kumar
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar; New Delhi 110025 India
| | - Amresh Prakash
- School of Computational and Integrative Sciences; Jawaharlal Nehru University; New Delhi 110067 India
| | - Andrew M. Lynn
- School of Computational and Integrative Sciences; Jawaharlal Nehru University; New Delhi 110067 India
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7
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Amani M, Barzegar A, Mazani M. Osmolytic Effect of Sucrose on Thermal Denaturation of Pea Seedling Copper Amine Oxidase. Protein J 2017; 36:147-153. [PMID: 28315108 DOI: 10.1007/s10930-017-9706-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Protein stability is a subject of interest by many researchers. One of the common methods to increase the protein stability is using the osmolytes. Many studies and theories analyzed and explained osmolytic effect by equilibrium thermodynamic while most proteins undergo an irreversible denaturation. In current study we investigated the effect of sucrose as an osmolyte on the thermal denaturation of pea seedlings amine oxidase by the enzyme activity, fluorescence spectroscopy, circular dichroism, and differential scanning calorimetry. All experiments are in agreement that pea seedlings amine oxidase denaturation is controlled kinetically and its kinetic stability is increased in presence of sucrose. Differential scanning calorimetry experiments at different scanning rates showed that pea seedlings amine oxidase unfolding obeys two-state irreversible model. Fitting the differential scanning calorimetry data to two-state irreversible model showed that unfolding enthalpy and T *, temperature at which rate constant equals unit per minute, are increased while activation energy is not affected by increase in sucrose concentration. We concluded that osmolytes decrease the molecular oscillation of irreversible proteins which leads to decline in unfolding rate constant.
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Affiliation(s)
- Mojtaba Amani
- Department of Biochemistry, Faculty of Medicine, Ardabil University of Medical Sciences (ArUMS), Daneshgah Street, Ardabil, 5618985991, Iran.
| | - Aboozar Barzegar
- Department of Biochemistry, Faculty of Medicine, Ardabil University of Medical Sciences (ArUMS), Daneshgah Street, Ardabil, 5618985991, Iran
| | - Mohammad Mazani
- Department of Biochemistry, Faculty of Medicine, Ardabil University of Medical Sciences (ArUMS), Daneshgah Street, Ardabil, 5618985991, Iran
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8
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Abdolvahabi A, Shi Y, Rasouli S, Croom CM, Chuprin A, Shaw BF. How Do Gyrating Beads Accelerate Amyloid Fibrillization? Biophys J 2017; 112:250-264. [PMID: 28122213 PMCID: PMC5266089 DOI: 10.1016/j.bpj.2016.12.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 11/22/2016] [Accepted: 12/05/2016] [Indexed: 01/21/2023] Open
Abstract
The chemical and physical mechanisms by which gyrating beads accelerate amyloid fibrillization in microtiter plate assays are unclear. Identifying these mechanisms will help optimize high-throughput screening assays for molecules and mutations that modulate aggregation and might explain why different research groups report different rates of aggregation for identical proteins. This article investigates how the rate of superoxide dismutase-1 (SOD1) fibrillization is affected by 12 different beads with a wide range of hydrophobicity, mass, stiffness, and topology but identical diameter. All assays were performed on D90A apo-SOD1, which is a stable and wild-type-like variant of SOD1. The most significant and uniform correlation between any material property of each bead and that bead's effect on SOD1 fibrillization rate was with regard to bead mass. A linear correlation existed between bead mass and rate of fibril elongation (R2 = 0.7): heavier beads produced faster rates and shorter fibrils. Nucleation rates (lag time) also correlated with bead mass, but only for non-polymeric beads (i.e., glass, ceramic, metallic). The effect of bead mass on fibrillization correlated (R2 = 0.96) with variations in buoyant forces and contact forces (between bead and microplate well), and was not an artifact of residual momentum during intermittent gyration. Hydrophobic effects were observed, but only for polymeric beads: lag times correlated negatively with contact angle of water and degree of protein adhesion (surface adhesion and hydrophobic effects were negligible for non-polymeric beads). These results demonstrate that contact forces (alone) explain kinetic variation among non-polymeric beads, whereas surface hydrophobicity and contact forces explain kinetic variation among polymeric beads. This study also establishes conditions for high-throughput amyloid assays of SOD1 that enable the control over fibril morphologies and produce eightfold faster lag times and fourfold less stochasticity than in previous studies.
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Affiliation(s)
| | - Yunhua Shi
- Department of Chemistry and Biochemistry, Baylor University, Waco, Texas
| | - Sanaz Rasouli
- Department of Chemistry and Biochemistry, Baylor University, Waco, Texas; Institute of Biomedical Studies, Baylor University, Waco, Texas
| | - Corbin M Croom
- Department of Chemistry and Biochemistry, Baylor University, Waco, Texas
| | - Aleksandra Chuprin
- Department of Chemistry and Biochemistry, Baylor University, Waco, Texas
| | - Bryan F Shaw
- Department of Chemistry and Biochemistry, Baylor University, Waco, Texas.
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9
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Jangholi A, Ashrafi-Kooshk MR, Arab SS, Riazi G, Mokhtari F, Poorebrahim M, Mahdiuni H, Kurganov BI, Moosavi-Movahedi AA, Khodarahmi R. Appraisal of role of the polyanionic inducer length on amyloid formation by 412-residue 1N4R Tau protein: A comparative study. Arch Biochem Biophys 2016; 609:1-19. [DOI: 10.1016/j.abb.2016.09.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 09/08/2016] [Accepted: 09/12/2016] [Indexed: 10/21/2022]
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10
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Alcaráz MR, Schwaighofer A, Goicoechea H, Lendl B. EC-QCL mid-IR transmission spectroscopy for monitoring dynamic changes of protein secondary structure in aqueous solution on the example of β-aggregation in alcohol-denaturated α-chymotrypsin. Anal Bioanal Chem 2016; 408:3933-41. [PMID: 27007739 PMCID: PMC4873525 DOI: 10.1007/s00216-016-9464-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 01/22/2016] [Accepted: 03/02/2016] [Indexed: 11/24/2022]
Abstract
In this work, a novel EC-QCL-based setup for mid-IR transmission measurements in the amide I region is introduced for monitoring dynamic changes in secondary structure of proteins. For this purpose, α-chymotrypsin (aCT) acts as a model protein, which gradually forms intermolecular β-sheet aggregates after adopting a non-native α-helical structure induced by exposure to 50 % TFE. In order to showcase the versatility of the presented setup, the effects of varying pH values and protein concentration on the rate of β-aggregation were studied. The influence of the pH value on the initial reaction rate was studied in the range of pH 5.8-8.2. Results indicate an increased aggregation rate at elevated pH values. Furthermore, the widely accessible concentration range of the laser-based IR transmission setup was utilized to investigate β-aggregation across a concentration range of 5-60 mg mL(-1). For concentrations lower than 20 mg mL(-1), the aggregation rate appears to be independent of concentration. At higher values, the reaction rate increases linearly with protein concentration. Extended MCR-ALS was employed to obtain pure spectral and concentration profiles of the temporal transition between α-helices and intermolecular β-sheets. Comparison of the global solutions obtained by the modelled data with results acquired by the laser-based IR transmission setup at different conditions shows excellent agreement. This demonstrates the potential and versatility of the EC-QCL-based IR transmission setup to monitor dynamic changes of protein secondary structure in aqueous solution at varying conditions and across a wide concentration range. Graphical abstract EC-QCL IR spectroscopy for monitoring protein conformation change.
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Affiliation(s)
- Mirta R Alcaráz
- Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/164-UPA, 1060, Vienna, Austria
- Laboratorio de Desarrollo Analítico y Quimiometría, FBCB, Universidad Nacional del Litoral-CONICET, Ciudad Universitaria, 3000, Santa Fe, Argentina
| | - Andreas Schwaighofer
- Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/164-UPA, 1060, Vienna, Austria
| | - Héctor Goicoechea
- Laboratorio de Desarrollo Analítico y Quimiometría, FBCB, Universidad Nacional del Litoral-CONICET, Ciudad Universitaria, 3000, Santa Fe, Argentina
| | - Bernhard Lendl
- Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/164-UPA, 1060, Vienna, Austria.
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11
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Unfolding of insulin at the surface of ZnO quantum dots. Int J Biol Macromol 2016; 86:169-76. [DOI: 10.1016/j.ijbiomac.2016.01.075] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 01/17/2016] [Accepted: 01/21/2016] [Indexed: 01/05/2023]
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12
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Kumar A, Rani A, Venkatesu P. A comparative study of the effects of the Hofmeister series anions of the ionic salts and ionic liquids on the stability of α-chymotrypsin. NEW J CHEM 2015. [DOI: 10.1039/c4nj01596g] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Direct interactions between the anion and the catalytic amino acid residues lead to denaturation of CT.
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Affiliation(s)
- Awanish Kumar
- Department of Chemistry
- University of Delhi
- Delhi – 110 007
- India
| | - Anjeeta Rani
- Department of Chemistry
- University of Delhi
- Delhi – 110 007
- India
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13
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Gupta BS, Taha M, Lee MJ. Superactivity of α-chymotrypsin with biological buffers, TRIS, TES, TAPS, and TAPSO in aqueous solutions. RSC Adv 2014. [DOI: 10.1039/c4ra09434d] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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14
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Angelani CR, Curto LM, Cabanas IS, Caramelo JJ, Uversky VN, Delfino JM. Toward a common aggregation mechanism for a β-barrel protein family: Insights derived from a stable dimeric species. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2014; 1844:1599-607. [DOI: 10.1016/j.bbapap.2014.06.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 05/30/2014] [Accepted: 06/02/2014] [Indexed: 10/25/2022]
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15
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Impact of Residual Impurities and Contaminants on Protein Stability. J Pharm Sci 2014; 103:1315-30. [DOI: 10.1002/jps.23931] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Revised: 02/17/2014] [Accepted: 02/18/2014] [Indexed: 02/03/2023]
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16
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Curto LM, Angelani CR, Caramelo JJ, Delfino JM. Truncation of a β-barrel scaffold dissociates intrinsic stability from its propensity to aggregation. Biophys J 2013. [PMID: 23199921 DOI: 10.1016/j.bpj.2012.09.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Δ98Δ is a functional all-β sheet variant of intestinal fatty acid binding protein (IFABP) that was generated by controlled proteolysis. This framework is useful to study the molecular determinants related to aggregation of β-barrel proteins. Albeit displaying increased conformational plasticity, Δ98Δ exhibits a nativelike β-barrel topology and is able to support a cooperative folding behavior. Here we present a comparative study of IFABP and Δ98Δ regarding their conformational perturbation and aggregation propensity triggered by trifluoroethanol. Both proteins share a common nucleation-elongation mechanism, whereby the rate-limiting step is the formation of stable dimeric nuclei followed by the association of monomers to the growing aggregates. Despite leading to a less stable structure, the extensive truncation of IFABP yields a form exhibiting a somewhat lower tendency to aggregate. This finding appears at odds with the established notion that a perturbation of the native compact fold should necessarily favor the population of aggregation-prone species. In addition to the aggregation propensity dictated by a given amino-acid sequence, our contention holds that long-range interactions might also play a major role in determining the overall aggregation propensity.
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Affiliation(s)
- Lucrecia M Curto
- Department of Biological Chemistry and Institute of Biochemistry and Biophysics, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires, Argentina
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17
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Xia Y, Ji S, Park JS, Park I, Khoi PN, Lee J, Jung YD. Inactivation and conformational changes in methyl parathion hydrolase in 2,2,2-trifluoroethanol solutions: Inactivation kinetics and molecular dynamics simulation. Process Biochem 2013. [DOI: 10.1016/j.procbio.2013.02.031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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18
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Azami-Movahed M, Shariatizi S, Sabbaghian M, Ghasemi A, Ebrahim-Habibi A, Nemat-Gorgani M. Heme binding site in apomyoglobin may be effectively targeted with small molecules to control aggregation. Int J Biochem Cell Biol 2013; 45:299-307. [DOI: 10.1016/j.biocel.2012.10.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2012] [Revised: 10/08/2012] [Accepted: 10/11/2012] [Indexed: 12/31/2022]
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19
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Real-time analysis and direct observations of different superoxide dismutase (SOD1) molecules bindings to aggregates in temporal evolution step. Colloids Surf B Biointerfaces 2013; 101:266-71. [DOI: 10.1016/j.colsurfb.2012.06.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2012] [Revised: 06/18/2012] [Accepted: 06/19/2012] [Indexed: 11/19/2022]
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20
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Iram A, Naeem A. Conformational Transitions Provoked by Organic Solvents in Chicken Egg Ovalbumin: Mimicking the Local Environment. Protein J 2012; 32:7-14. [DOI: 10.1007/s10930-012-9453-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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21
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The interaction of α-chymotrypsin with one persistent organic pollutant (dicofol): Spectroscope and molecular modeling identification. Food Chem Toxicol 2012; 50:3298-305. [DOI: 10.1016/j.fct.2012.06.037] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Revised: 06/15/2012] [Accepted: 06/22/2012] [Indexed: 11/18/2022]
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22
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Khodarahmi R, Hossein-pour Z, Ghobadi S, Mansouri K, Mostafaie A, Yari K, Ghadami SA. Non-specific peroxidase activity and catalase-inhibitory behavior of fibrillar aggregates after interaction with heme: relevance to the etiology of amyloid-related neurodegenerative disorders using the experimental-based evidences. JOURNAL OF THE IRANIAN CHEMICAL SOCIETY 2012. [DOI: 10.1007/s13738-012-0111-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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23
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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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24
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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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25
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Diaz-Espinoza R, Mukherjee A, Soto C. Kosmotropic anions promote conversion of recombinant prion protein into a PrPSc-like misfolded form. PLoS One 2012; 7:e31678. [PMID: 22347503 PMCID: PMC3276510 DOI: 10.1371/journal.pone.0031678] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Accepted: 01/11/2012] [Indexed: 11/18/2022] Open
Abstract
Prions are self-propagating proteins involved in transmissible spongiform encephalopaties in mammals. An aberrant conformation with amyloid-like features of a cell surface protein, termed prion protein (PrP), is thought to be the essential component of the infectious particle, though accessory co-factor molecules such as lipids and nucleotides may be involved. The cellular co-factors and environmental conditions implicated in PrP misfolding are not completely understood. To address this issue, several studies have been done inducing misfolding of recombinant PrP (recPrP) into classical amyloid structures using partially denaturing conditions. In this work, we report that misfolding of recPrP into PrP(Sc)-like aggregates can be induced by simply incubating the protein in the presence of kosmotropic salts at concentrations that are known to retain or increase the stability of the protein. We used a simple experimental reaction (protein, buffer and salts) submitted to agitation/incubation cycles at physiological temperature and pH. The formation of protease resistant-recPrP was time and salt-concentration dependent and required the presence of kosmotropic anions such as F(-) or SO(4)(-2). The molecular weights of the protease resistant recPrP fragments are reminiscent of those found in degradation assays of bona fide PrP(Sc). The aggregates also exhibited PrP(Sc)-like ultrastructural features including rod-shape morphology under electron microscope, high beta-sheet content and thioflavin-T positive signal. The formation of recPrP aggregates with PrP(Sc) biochemical features under conditions closer to physiological in the absence of organic co-factor molecules provides a simple setup that may prove helpful to understand the molecular mechanism of PrP misfolding.
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Affiliation(s)
- Rodrigo Diaz-Espinoza
- Department of Neurology, Mitchell Center for Alzheimer's Disease and Related Brain Disorders, University of Texas Houston Medical School, Houston, Texas, United States of America
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Abhisek Mukherjee
- Department of Neurology, Mitchell Center for Alzheimer's Disease and Related Brain Disorders, University of Texas Houston Medical School, Houston, Texas, United States of America
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Claudio Soto
- Department of Neurology, Mitchell Center for Alzheimer's Disease and Related Brain Disorders, University of Texas Houston Medical School, Houston, Texas, United States of America
- * E-mail:
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Yin SJ, Lü ZR, Park D, Chung HY, Yang JM, Zhou HM, Qian GY, Park YD. Trifluoroethanol-induced changes in activity and conformation of manganese-containing superoxide dismutase. Appl Biochem Biotechnol 2011; 166:276-88. [PMID: 22057937 DOI: 10.1007/s12010-011-9423-8] [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] [Received: 03/23/2011] [Accepted: 10/18/2011] [Indexed: 11/26/2022]
Abstract
Superoxide dismutase (SOD, EC 1.15.1.1) plays an important role in antioxidant defense in organisms exposed to oxygen. However, there is a lack of research into the regulation of SOD activity and structural changes during folding, especially for SOD originating from extremophiles. We studied the inhibitory effects of trifluoroethanol (TFE) on the activity and conformation of manganese-containing SOD (Mn-SOD) from Thermus thermophilus. TFE decreased the degree of secondary structure of Mn-SOD, which directly resulted in enzyme inactivation and disrupted the tertiary structure of Mn-SOD. The kinetic studies showed that TFE-induced inactivation of Mn-SOD is a first-order reaction and that the regional Mn-contained active site is very stable compared to the overall structure. We further simulated the docking between Mn-SOD and TFE (binding energy for Dock 6.3, -9.68 kcal/mol) and predicted that the LEU9, TYR13, and HIS29 residues outside of the active site interact with TFE. Our results provide insight into the inactivation of Mn-SOD during unfolding in the presence of TFE and allow us to describe ligand binding via inhibition kinetics combined with computational predictions.
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Affiliation(s)
- Shang-Jun Yin
- College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo 315100, People's Republic of China
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27
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Hong S, Lee S, Yi J. Sensitive and molecular size-selective detection of proteins using a chip-based and heteroliganded gold nanoisland by localized surface plasmon resonance spectroscopy. NANOSCALE RESEARCH LETTERS 2011; 6:336. [PMID: 21711878 PMCID: PMC3211424 DOI: 10.1186/1556-276x-6-336] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2010] [Accepted: 04/14/2011] [Indexed: 05/31/2023]
Abstract
A highly sensitive and molecular size-selective method for the detection of proteins using heteroliganded gold nanoislands and localized surface plasmon resonance (LSPR) is described. Two different heteroligands with different chain lengths (3-mercaptopionicacid and decanethiol) were used in fabricating nanoholes for the size-dependent separation of a protein in comparison with its aggregate. Their ratios on gold nanoisland were optimized for the sensitive detection of superoxide dismutase (SOD1). This protein has been implicated in the pathology of amyotrophic lateral sclerosis (ALS). Upon exposure of the optimized gold nanoisland to a solution of SOD1 and aggregates thereof, changes in the LSPR spectra were observed which are attributed to the size-selective and covalent chemical binding of SOD1 to the nanoholes. With a lower detection limit of 1.0 ng/ml, the method can be used to selectively detect SOD1 in the presence of aggregates at the molecular level.
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Affiliation(s)
- Surin Hong
- World Class University (WCU) Program of Chemical Convergence for Energy & Environment (C2E2), School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul 151-744, Korea
| | - Suseung Lee
- World Class University (WCU) Program of Chemical Convergence for Energy & Environment (C2E2), School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul 151-744, Korea
| | - Jongheop Yi
- World Class University (WCU) Program of Chemical Convergence for Energy & Environment (C2E2), School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, Seoul 151-744, Korea
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28
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Singh SM, Cabello-Villegas J, Hutchings RL, Mallela KMG. Role of partial protein unfolding in alcohol-induced protein aggregation. Proteins 2010; 78:2625-37. [PMID: 20597088 DOI: 10.1002/prot.22778] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Proteins aggregate in response to various stresses including changes in solvent conditions. Addition of alcohols has been recently shown to induce aggregation of disease-related as well as nondisease-related proteins. Here we probed the biophysical mechanisms underlying alcohol-induced protein aggregation, in particular the role of partial protein unfolding in aggregation. We have studied aggregation mechanisms due to benzyl alcohol which is used in numerous biochemical and biotechnological applications. We chose cytochrome c as a model protein, for the reason that various optical and structural probes are available to monitor its global and partial unfolding reactions. Benzyl alcohol induced the aggregation of cytochrome c in isothermal conditions and decreased the temperature at which the protein aggregates. However, benzyl alcohol did not perturb the overall native conformation of cytochrome c. Instead, it caused partial unfolding of a local protein region around the methionine residue at position 80. Site-specific optical probes, two-dimensional NMR titrations, and hydrogen exchange all support this conclusion. The protein aggregation temperature varied linearly with the melting temperature of the Met80 region. Stabilizing the Met80 region by heme iron reduction drastically decreased protein aggregation, which confirmed that the local unfolding of this region causes protein aggregation. These results indicate that a possible mechanism by which alcohols induce protein aggregation is through partial rather than complete unfolding of native proteins.
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Affiliation(s)
- Surinder M Singh
- Department of Pharmaceutical Sciences and Center for Pharmaceutical Biotechnology, School of Pharmacy, University of Colorado Denver, 12700 E 19th Avenue, C238-P15, Aurora, Colorado 80045, USA
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29
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Lim KH, Le YTH, Collver HH, Putnam-Evans C, Kenney JM. Characterization of amyloidogenic intermediate states through a combined use of CD and NMR spectroscopy. Biophys Chem 2010; 151:155-9. [PMID: 20619955 DOI: 10.1016/j.bpc.2010.06.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2009] [Revised: 06/10/2010] [Accepted: 06/14/2010] [Indexed: 11/30/2022]
Abstract
Characterization of amyloidogenic intermediate states is of central importance in understanding the molecular mechanism of amyloid formation. In this study, we utilized CD and NMR spectroscopy to investigate secondary structure of the monomeric amyloidogenic intermediate of a beta-structured SH3 domain, which was induced by trifluoroethanol (TFE). The combined biophysical studies showed that the native state SH3 domain is gradually converted to the amyloidogenic intermediate state at TFE concentrations of 20-26% (v/v) and the aggregation-prone state contains substantial amount of the beta-sheet conformation ( approximately 30%) with disordered (54%) and some helical characters (16%). Under weaker amyloidogenic conditions of higher TFE concentrations (>40%), the beta-sheet structures were gradually changed to helical conformations and the relative content of the helical and beta-sheet conformations was highly correlated with the aggregation propensity of the SH3 domain. This indicates that the beta-sheet characters of the amyloidogenic states may be critical to the effective amyloid formation.
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Affiliation(s)
- Kwang Hun Lim
- Department of Chemistry, East Carolina University, Greenville, NC 27858, United States.
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30
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Filippov AV, Gröbner G, Antzutkin ON. Aggregation of amyloid Abeta((1-40)) peptide in perdeuterated 2,2,2-trifluoroethanol caused by ultrasound sonication. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2010; 48:427-434. [PMID: 20474020 DOI: 10.1002/mrc.2596] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Ultrasound sonication of protein and peptide solutions is routinely used in biochemical, biophysical, pharmaceutical and medical sciences to facilitate and accelerate dissolution of macromolecules in both aqueous and organic solvents. However, the impact of ultrasound waves on folding/unfolding of treated proteins, in particular, on aggregation kinetics of amyloidogenic peptides and proteins is not understood. In this work, effects of ultrasound sonication on the misfolding and aggregation behavior of the Alzheimer's Abeta((1-40))-peptide is studied by pulsed-field gradient (PFG) spin-echo diffusion NMR and UV circular dichroism (CD) spectroscopy. Upon simple dissolution of Abeta((1-40)) in perdeuterated trifluoroethanol, CF(3)-CD(2)-OD (TFE-d(3)), the peptide is present in the solution as a stable monomer adopting alpha-helical secondary structural motifs. The self-diffusion coefficient of Abeta((1-40)) monomers in TFE-d(3) was measured as 1.35 x 10(-10) m(2) s(-1), reflecting its monomeric character. However, upon ultrasonic sonication for less than 5 min, considerable populations of Abeta molecules (ca 40%) form large aggregates as reflected in diffusion coefficients smaller than 4.0 x 10(-13) m(2) s(-1). Sonication for longer times (up to 40 min in total) effectively reduces the fraction of these aggregates in (1)H PFG NMR spectra to ca 25%. Additionally, absorption below 230 nm increased significantly upon sonication treatment, an observation, which also clearly confirms the ongoing aggregation process of Abeta((1-40)) in TFE-d(3). Surprisingly, upon ultrasound sonication only small changes in the peptide secondary structure were detected by CD: the peptide molecules mainly adopt alpha-helical motifs in both monomers and aggregates formed upon sonication.
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Affiliation(s)
- Andrei V Filippov
- Division of Chemical Engineering, Luleå University of Technology, Luleå SE-97187, Sweden.
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31
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Khodarahmi R, Soori H, Amani M. Study of cosolvent-induced alpha-chymotrypsin fibrillogenesis: does protein surface hydrophobicity trigger early stages of aggregation reaction? Protein J 2010; 28:349-61. [PMID: 19768527 DOI: 10.1007/s10930-009-9200-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The misfolding of specific proteins is often associated with their assembly into fibrillar aggregates, commonly termed amyloid fibrils. Despite the many efforts expended to characterize amyloid formation in vitro, there is no deep knowledge about the environment (in which aggregation occurs) as well as mechanism of this type of protein aggregation. Alpha-chymotrypsin was recently driven toward amyloid aggregation by the addition of intermediate concentrations of trifluoroethanol. In the present study, approaches such as turbidimetric, thermodynamic, intrinsic fluorescence and quenching studies as well as chemical modification have been successfully used to elucidate the underlying role of hydrophobic interactions (involved in early stages of amyloid formation) in alpha-chymotrypsin-based experimental system.
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Affiliation(s)
- Reza Khodarahmi
- Department of Pharmacognosy and Biotechnology, Faculty of Pharmacy, Kermanshah University of Medical Sciences, P. O. Box 67145-1673, Kermanshah, Iran.
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32
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Wang W, Nema S, Teagarden D. Protein aggregation—Pathways and influencing factors. Int J Pharm 2010; 390:89-99. [DOI: 10.1016/j.ijpharm.2010.02.025] [Citation(s) in RCA: 503] [Impact Index Per Article: 35.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2009] [Revised: 01/08/2010] [Accepted: 02/17/2010] [Indexed: 11/25/2022]
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33
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Heme, as a chaperone, binds to amyloid fibrils and forms peroxidase in vitro: Possible evidence on critical role of non-specific peroxidase activity in neurodegenerative disease onset/progression using the α-crystallin-based experimental system. Arch Biochem Biophys 2010; 494:205-15. [DOI: 10.1016/j.abb.2009.12.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2009] [Revised: 12/07/2009] [Accepted: 12/08/2009] [Indexed: 11/23/2022]
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34
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The Effect of Trifluoroethanol on Tyrosinase Activity and Conformation: Inhibition Kinetics and Computational Simulations. Appl Biochem Biotechnol 2009; 160:1896-908. [DOI: 10.1007/s12010-009-8730-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2008] [Accepted: 07/26/2009] [Indexed: 10/20/2022]
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35
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Rezaei-Ghaleh N, Zweckstetter M, Morshedi D, Ebrahim-Habibi A, Nemat-Gorgani M. Amyloidogenic potential of alpha-chymotrypsin in different conformational states. Biopolymers 2009; 91:28-36. [PMID: 18767127 DOI: 10.1002/bip.21079] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Amyloid fibril formation is widely believed to be a generic property of polypeptide chains. In the present study, alpha-chymotrypsin, a well-known serine protease has been driven toward these structures by the use of two different conditions involving (I) high temperature, pH 2.5, and (II) low concentration of trifluoroethanol (TFE), pH 2.5. A variety of experimental methods, including fluorescence emission, dynamic quenching, steady-state fluorescence anisotropy, far-UV circular dichroism, nuclear magnetic resonance spectroscopy, and dynamic light scattering were employed to characterize the conformational states of alpha-chymotrypsin that precede formation of amyloid fibrils. The structure formed under Condition I was an unfolded monomer, whereas an alpha-helical rich oligomer was induced in Condition II. Both the amyloid aggregation-prone species manifested a higher solvent exposure of hydrophobic and aromatic residues compared with the native state. Upon incubation of the protein in these conditions for 48 h, amyloid-like fibrils were formed with diameters of about 10-12 nm. In contrast, at neutral pH and low concentration of TFE, a significant degree of amorphous aggregation was observed, suggesting that charge neutralization of acidic residues in the amyloid core region has a positive influence on amyloid fibril formation. In summary, results presented in this communication suggest that amyloid fibrils of alpha-chymotrypsin may be obtained from a variety of structurally distinct conformational ensembles highlighting the critical importance of protein evolution mechanisms related to prevention of protein misfolding.
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Affiliation(s)
- Nasrollah Rezaei-Ghaleh
- Department for NMR-based Structural Biology, Max-Planck-Institute for Biophysical Chemistry, Göttingen, Germany
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36
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Chaperone-like activity of heme group against amyloid-like fibril formation by hen egg ovalbumin: Possible mechanism of action. Int J Biol Macromol 2009; 44:98-106. [DOI: 10.1016/j.ijbiomac.2008.10.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2008] [Revised: 10/18/2008] [Accepted: 10/20/2008] [Indexed: 11/19/2022]
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37
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Rezaei-Ghaleh N, Amininasab M, Nemat-Gorgani M. Conformational changes of alpha-chymotrypsin in a fibrillation-promoting condition: a molecular dynamics study. Biophys J 2008; 95:4139-47. [PMID: 18658209 PMCID: PMC2567952 DOI: 10.1529/biophysj.108.132407] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2008] [Accepted: 07/07/2008] [Indexed: 11/18/2022] Open
Abstract
Amyloid nanofibril formation appears to be a generic property of polypeptide chains. alpha-Chymotrypsin (aCT) was recently driven toward amyloid-like aggregation by the addition of trifluoroethanol (TFE) at intermediate concentrations. In this study we employed a molecular dynamics simulation to investigate the early events in TFE-induced conformational changes of aCT that precede amyloid formation, and compared the results of the simulation with previous experiments. TFE molecules were found to rapidly replace the water molecules closely associated with the protein surface. The gyration radius, together with total and hydrophobic solvent-accessible surface areas of aCT, was significantly increased. In accord with the experimental observations, the extended beta-conformation of backbone was increased. The secondary structural elements of aCT in water and TFE/water mixture showed a reasonable fit, whereas significant deviations were observed for several loops. These alterations originated largely from main-chain rotations at glycine residues. The catalytic active site and S1 binding pocket of the enzyme were also distorted in the TFE/water mixture. The obtained results are suggested to provide more insights into the conformational properties of the amyloid aggregation-prone protein species. Possible mechanisms of TFE-induced alterations in the conformation and dynamics of the protein structure are also discussed.
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Affiliation(s)
- Nasrollah Rezaei-Ghaleh
- Institute of Biochemistry and Biophysics, Department of Cell and Molecular Biology, Faculty of Science, University of Tehran, Tehran, Iran
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38
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Khodarahmi R, Beyrami M, Soori H. Appraisal of casein’s inhibitory effects on aggregation accompanying carbonic anhydrase refolding and heat-induced ovalbumin fibrillogenesis. Arch Biochem Biophys 2008; 477:67-76. [DOI: 10.1016/j.abb.2008.04.028] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2008] [Revised: 04/22/2008] [Accepted: 04/25/2008] [Indexed: 11/28/2022]
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39
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Holley M, Eginton C, Schaefer D, Brown LR. Characterization of amyloidogenesis of hen egg lysozyme in concentrated ethanol solution. Biochem Biophys Res Commun 2008; 373:164-8. [DOI: 10.1016/j.bbrc.2008.06.018] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2008] [Accepted: 06/05/2008] [Indexed: 10/21/2022]
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40
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Wang S, Kim YK, Chang YT. Diversity-Oriented Fluorescence Library Approach (DOFLA) to the Discovery of Chymotrypsin Sensor. ACTA ACUST UNITED AC 2008; 10:460-5. [DOI: 10.1021/cc700189b] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shenliang Wang
- Department of Chemistry, New York University, New York, New York 10003, Department of Chemistry and NUS MedChem Program of the Office of Life Sciences, National University of Singapore, Singapore 117543, and Laboratory of Bioimaging Probe Development, Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A*STAR), Biopolis, Singapore 138667
| | - Yun Kyung Kim
- Department of Chemistry, New York University, New York, New York 10003, Department of Chemistry and NUS MedChem Program of the Office of Life Sciences, National University of Singapore, Singapore 117543, and Laboratory of Bioimaging Probe Development, Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A*STAR), Biopolis, Singapore 138667
| | - Young-Tae Chang
- Department of Chemistry, New York University, New York, New York 10003, Department of Chemistry and NUS MedChem Program of the Office of Life Sciences, National University of Singapore, Singapore 117543, and Laboratory of Bioimaging Probe Development, Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A*STAR), Biopolis, Singapore 138667
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Rezaei-Ghaleh N, Ramshini H, Ebrahim-Habibi A, Moosavi-Movahedi AA, Nemat-Gorgani M. Thermal aggregation of α-chymotrypsin: Role of hydrophobic and electrostatic interactions. Biophys Chem 2008; 132:23-32. [DOI: 10.1016/j.bpc.2007.10.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2007] [Revised: 09/30/2007] [Accepted: 10/01/2007] [Indexed: 10/22/2022]
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42
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Rezaei-Ghaleh N, Ebrahim-Habibi A, Moosavi-Movahedi AA, Nemat-Gorgani M. Effect of polyamines on the structure, thermal stability and 2,2,2-trifluoroethanol-induced aggregation of alpha-chymotrypsin. Int J Biol Macromol 2007; 41:597-604. [PMID: 17850860 DOI: 10.1016/j.ijbiomac.2007.07.018] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2007] [Revised: 07/29/2007] [Accepted: 07/30/2007] [Indexed: 11/27/2022]
Abstract
Naturally occurring polyamines are known to interact with a variety of biomolecules and critically involve in some important physiological processes. They have also been shown to influence protein aggregation in vitro in some cases. The aim of the present study was to investigate how polyamines may influence the structure and thermal stability of alpha-chymotrypsin and modulate alcohol-induced aggregation of this protein. Various techniques, including turbidity measurements, tensiometry, DSC, intrinsic fluorescence and far- and near-UV circular dichroism spectroscopy were used to examine the effect of putrescine and spermidine on alpha-chymotrypsin. While slight changes in the secondary and tertiary structure of the protein was observed, a clear stabilizing effect against its thermal unfolding was achieved. Moreover, the polyamines were found to inhibit TFE-induced aggregation at 32% TFE and promote formation of non-native alpha-helices in the protein structure. Based on the observed increase in surface tension induced by polyamines, it is suggested that their effects on enhancing thermal stability and alcohol-induced alpha-helices formation may be due to their kosmotropic properties.
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