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Kosmachevskaya OV, Novikova NN, Yakunin SN, Topunov AF. Formation of Supplementary Metal-Binding Centers in Proteins under Stress Conditions. BIOCHEMISTRY. BIOKHIMIIA 2024; 89:S180-S204. [PMID: 38621750 DOI: 10.1134/s0006297924140104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 09/21/2023] [Accepted: 10/29/2023] [Indexed: 04/17/2024]
Abstract
In many proteins, supplementary metal-binding centers appear under stress conditions. They are known as aberrant or atypical sites. Physico-chemical properties of proteins are significantly changed after such metal binding, and very stable protein aggregates are formed, in which metals act as "cross-linking" agents. Supplementary metal-binding centers in proteins often arise as a result of posttranslational modifications caused by reactive oxygen and nitrogen species and reactive carbonyl compounds. New chemical groups formed as a result of these modifications can act as ligands for binding metal ions. Special attention is paid to the role of cysteine SH-groups in the formation of supplementary metal-binding centers, since these groups are the main target for the action of reactive species. Supplementary metal binding centers may also appear due to unmasking of amino acid residues when protein conformation changing. Appearance of such centers is usually considered as a pathological process. Such unilateral approach does not allow to obtain an integral view of the phenomenon, ignoring cases when formation of metal complexes with altered proteins is a way to adjust protein properties, activity, and stability under the changed redox conditions. The role of metals in protein aggregation is being studied actively, since it leads to formation of non-membranous organelles, liquid condensates, and solid conglomerates. Some proteins found in such aggregates are typical for various diseases, such as Alzheimer's and Huntington's diseases, amyotrophic lateral sclerosis, and some types of cancer.
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Affiliation(s)
- Olga V Kosmachevskaya
- Bach Institute of Biochemistry, Research Center of Biotechnology, Russian Academy of Sciences, Moscow, 119071, Russia
| | | | - Sergey N Yakunin
- National Research Center "Kurchatov Institute", Moscow, 123182, Russia
| | - Alexey F Topunov
- Bach Institute of Biochemistry, Research Center of Biotechnology, Russian Academy of Sciences, Moscow, 119071, Russia.
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2
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Anjali, Kishore N. Influence of amino acids on alkaline pH induced partially folded molten globule like intermediate of bovine serum albumin: Conformational and thermodynamic insights. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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3
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Chura-Chambi RM, Farah CS, Morganti L. Human growth hormone inclusion bodies present native-like secondary and tertiary structures which can be preserved by mild solubilization for refolding. Microb Cell Fact 2022; 21:164. [PMID: 35978337 PMCID: PMC9382763 DOI: 10.1186/s12934-022-01887-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 08/02/2022] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Native-like secondary structures and biological activity have been described for proteins in inclusion bodies (IBs). Tertiary structure analysis, however, is hampered due to the necessity of mild solubilization conditions. Denaturing reagents used for IBs solubilization generally lead to the loss of these structures and to consequent reaggregation due to intermolecular interactions among exposed hydrophobic domains after removal of the solubilization reagent. The use of mild, non-denaturing solubilization processes that maintain existing structures could allow tertiary structure analysis and increase the efficiency of refolding. RESULTS In this study we use a variety of biophysical methods to analyze protein structure in human growth hormone IBs (hGH-IBs). hGH-IBs present native-like secondary and tertiary structures, as shown by far and near-UV CD analysis. hGH-IBs present similar λmax intrinsic Trp fluorescence to the native protein (334 nm), indicative of a native-like tertiary structure. Similar fluorescence behavior was also obtained for hGH solubilized from IBs and native hGH at pH 10.0 and 2.5 kbar and after decompression. hGH-IBs expressed in E. coli were extracted to high yield and purity (95%) and solubilized using non-denaturing conditions [2.4 kbar, 0.25 M arginine (pH 10), 10 mM DTT]. After decompression, the protein was incubated at pH 7.4 in the presence of the glutathione-oxidized glutathione (GSH-GSSG) pair which led to intramolecular disulfide bond formation and refolded hGH (81% yield). CONCLUSIONS We have shown that hGH-IBs present native-like secondary and tertiary structures and that non-denaturing methods that aim to preserve them can lead to high yields of refolded protein. It is likely that the refolding process described can be extended to different proteins and may be particularly useful to reduce the pH required for alkaline solubilization.
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Affiliation(s)
- Rosa Maria Chura-Chambi
- Centro de Biotecnologia, Instituto de Pesquisas Energéticas e Nucleares, IPEN-CNEN/SP, São Paulo, SP, Brazil
| | - Chuck Shaker Farah
- Departamento de Bioquímica, Instituto de Química da Universidade de São Paulo, São Paulo, SP, Brazil
| | - Ligia Morganti
- Centro de Biotecnologia, Instituto de Pesquisas Energéticas e Nucleares, IPEN-CNEN/SP, São Paulo, SP, Brazil.
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Expression, purification, and biophysical characterization of recombinant MERS-CoV main (M pro) protease. Int J Biol Macromol 2022; 209:984-990. [PMID: 35452699 PMCID: PMC9017057 DOI: 10.1016/j.ijbiomac.2022.04.077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 04/04/2022] [Accepted: 04/11/2022] [Indexed: 11/21/2022]
Abstract
MERS-CoV main protease (Mpro) is essential for the maturation of the coronavirus; therefore, considered a potential drug target. Detailed conformational information is essential to developing antiviral therapeutics. However, the conformation of MERS-CoV Mpro under different conditions is poorly characterized. In this study, MERS-CoV Mpro was recombinantly produced in E.coli and characterized its structural stability with respect to changes in pH and temperatures. The intrinsic and extrinsic fluorescence measurements revealed that MERS-CoV Mpro tertiary structure was exposed to the polar environment due to the unfolding of the tertiary structure. However, the secondary structure of MERS-CoV Mpro was gained at low pH because of charge-charge repulsion. Furthermore, differential scanning fluorometry studies of Mpro showed a single thermal transition at all pHs except at pH 2.0; no transitions were observed. The data from the spectroscopic studies suggest that the MERS-CoV Mpro forms a molten globule-like state at pH 2.0. Insilico studies showed that the covid-19 Mpro shows 96.08% and 50.65% similarity to that of SARS-CoV Mpro and MERS-CoV Mpro, respectively. This study provides a basic understanding of the thermodynamic and structural properties of MERS-CoV Mpro.
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5
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Parray ZA, Naqvi AAT, Ahmad F, Hassan MI, Islam A. Characterization of different intermediate states in myoglobin induced by polyethylene glycol: A process of spontaneous molecular self-organization foresees the energy landscape theory via in vitro and in silico approaches. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.117502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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6
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Gausterer JC, Schüßler C, Gabor F. The impact of calcium phosphate on FITC-BSA loading of sonochemically prepared PLGA nanoparticles for inner ear drug delivery elucidated by two different fluorimetric quantification methods. ULTRASONICS SONOCHEMISTRY 2021; 79:105783. [PMID: 34653915 PMCID: PMC8527049 DOI: 10.1016/j.ultsonch.2021.105783] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Revised: 09/25/2021] [Accepted: 10/05/2021] [Indexed: 06/13/2023]
Abstract
Although therapeutically active proteins are highly efficacious, their content in protective nanoparticles is often too low to elicit adequate plasma levels. A strategy to increase protein loading is the in-situ generation of calcium phosphate as a protein adsorbent. To verify this approach, a highly sensitive and reliable fluorimetric method for quantification of incorporated fluorescein-labelled bovine serum albumin (FITC-BSA) as a model protein drug was developed. Dequenching the fluorescein label by pronase E, which digests the protein backbone, and dissolving the nanoparticle matrix in acetonitrile enabled FITC-BSA quantification in the nanogram per milliliter range. This test was confirmed by a second assay involving alkaline hydrolysis of FITC-BSA and the matrix. Nanoparticles prepared with calcium phosphate contained 40 µg FITC-BSA/mg and nanoparticles without calcium phosphate only 15 µg FITC-BSA/mg, representing a 2.7-fold increase in model protein loading. In this work the nanoparticle preparation procedure was optimized in terms of size for administration in the inner ear, but the range of applications is not limited.
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Affiliation(s)
- Julia Clara Gausterer
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Vienna, Austria.
| | - Clara Schüßler
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Vienna, Austria
| | - Franz Gabor
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Vienna, Austria.
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7
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Arabi SH, Aghelnejad B, Volmer J, Hinderberger D. Hydrogels from serum albumin in a molten globule-like state. Protein Sci 2020; 29:2459-2467. [PMID: 33058378 PMCID: PMC7679958 DOI: 10.1002/pro.3976] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 10/06/2020] [Accepted: 10/06/2020] [Indexed: 01/01/2023]
Abstract
We demonstrate that a molten globule‐like (MG) state of a protein, usually described as a compact yet non‐folded conformation that is only present in a narrow and delicate parameter range, is preserved in the high concentration environment of the protein hydrogel. We reveal mainly by means of electron paramagnetic resonance (EPR) spectroscopy that bovine serum albumin (BSA) retains the known basic MG state after a hydrogel has been formed from 20 wt% precursor solutions. At pH values of ~11.4, BSA hydrogels made from MG‐BSA remain stable for weeks, while gels formed at slightly different (~0.2) pH units above and below the MG‐state value dissolve into viscous solutions. On the contrary, when hydrophobic screening agents are added such as amphiphilic, EPR‐active stearic acid derivatives (16‐DOXYL‐stearic acid, 16‐DSA), the MG‐state based hydrogel is the least long‐lived, as the hydrophobic interaction of delicately exposed hydrophobic patches of BSA molecules is screened by the amphiphilic molecules. These bio‐ and polymer‐physically unexpected findings may lead to new bio‐compatible MG‐based hydrogels that display novel properties in comparison to conventional gels.
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Affiliation(s)
- Seyed Hamidreza Arabi
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany
| | - Behdad Aghelnejad
- Département de chimie, École normale supérieure, PSL University, Sorbonne Université, Paris, France
| | - Jonas Volmer
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany
| | - Dariush Hinderberger
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Halle (Saale), Germany
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8
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Parray ZA, Ahmad F, Alajmi MF, Hussain A, Hassan MI, Islam A. Formation of molten globule state in horse heart cytochrome c under physiological conditions: Importance of soft interactions and spectroscopic approach in crowded milieu. Int J Biol Macromol 2020; 148:192-200. [PMID: 31945437 DOI: 10.1016/j.ijbiomac.2020.01.119] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 01/07/2020] [Accepted: 01/12/2020] [Indexed: 11/17/2022]
Abstract
To understand protein folding problem under physiological condition, usually taken as dilute aqueous buffer at pH 7.0 and 25 °C, knowledge of properties of folding intermediates is important, such as molten globule (MG). We observed that polyethylene glycol 400 Da (PEG 400) induces molten globule state conformation in cytochrome c at pH 7.0 and 25 °C. This PEG-induced MG state has: (i) native tertiary structure partially perturbed, (ii) unperturbed native secondary structure, (iii) newly exposed hydrophobic patches, and (iv) has 1.58 times more hydrodynamic volume than that of the native protein. Isothermal titration calorimetry and docking studies showed specific binding between PEG 400 and cytochrome c. The study delineates that PEG-protein interactions are more complex than the excluded-volume. The soft interactions need to be seriously studied in crowding milieu that leads to destabilization of protein and overcome stabilizing exclusion volume effect. This study not only can help in unraveling the mystery of steps involved in the proper folding of proteins to solve the massively complicated problems of protein folding but also provides novel insights towards importance of structural change in proteins inside cell where intermediate states of protein import-export easily via membranes rather than native form of proteins.
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Affiliation(s)
- Zahoor Ahmad Parray
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Faizan Ahmad
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Mohamed F Alajmi
- Department of Pharmacognosy, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Afzal Hussain
- Department of Pharmacognosy, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Md Imtaiyaz Hassan
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Asimul Islam
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India.
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9
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Prasanthan P, Kishore N. Alkali induced unique partially folded state of bovine serum albumin: qualitative and quantitative insights. Int J Biol Macromol 2019; 138:252-261. [DOI: 10.1016/j.ijbiomac.2019.07.082] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 07/08/2019] [Accepted: 07/11/2019] [Indexed: 01/31/2023]
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10
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Kluz M, Nieznańska H, Dec R, Dzięcielewski I, Niżyński B, Ścibisz G, Puławski W, Staszczak G, Klein E, Smalc-Koziorowska J, Dzwolak W. Revisiting the conformational state of albumin conjugated to gold nanoclusters: A self-assembly pathway to giant superstructures unraveled. PLoS One 2019; 14:e0218975. [PMID: 31247048 PMCID: PMC6597083 DOI: 10.1371/journal.pone.0218975] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 06/12/2019] [Indexed: 11/21/2022] Open
Abstract
Bovine serum albumin (BSA) is often employed as a proteinaceous component for synthesis of luminescent protein-stabilized gold nanoclusters (AuNC): intriguing systems with many potential applications. Typically, the formation of BSA-AuNC conjugate occurs under strongly alkaline conditions. Due to the sheer complexity of intertwined chemical and structural transitions taking place upon BSA-AuNC formation, the state of albumin enveloping AuNCs remains poorly characterized. Here, we study the conformational properties of BSA bound to AuNCs using an array of biophysical tools including vibrational spectroscopy, circular dichroism, fluorescence spectroscopy and trypsin digestion. The alkaline conditions of BSA-AuNC self-assembly appear to be primary responsible for the profound irreversible disruption of tertiary contacts, partial unfolding of native α-helices, hydrolysis of disulfide bonds and the protein becoming vulnerable to trypsin digestion. Further unfolding of BSA-AuNC by guanidinium hydrochloride (GdnHCl) is fully reversible equally in terms of albumin's secondary structure and conjugate's luminescent properties. This suggests that binding to AuNCs traps the albumin molecule in a state that is both partly disordered and refractory to irreversible misfolding. Indeed, when BSA-AuNC is subjected to conditions favoring self-association of BSA into amyloid-like fibrils, the buildup of non-native β-sheet conformation is less pronounced than in a control experiment with unmodified BSA. Unexpectedly, BSA-AuNC reveals a tendency to self-assemble into giant twisted superstructures of micrometer lengths detectable with transmission electron microscopy (TEM), a property absent in unmodified BSA. The process is accompanied by ordering of bound AuNCs into elongated streaks and simultaneous decrease in fluorescence intensity. The newly discovered self-association pathway appears to be specifically accessible to protein molecules with a certain restriction on structural dynamics which in the case of BSA-AuNC arises from binding to metal nanoclusters. Our results have been discussed in the context of mechanisms of protein misfolding and applications of BSA-AuNC.
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MESH Headings
- Amino Acid Sequence
- Animals
- Cattle
- Circular Dichroism
- Gold/chemistry
- Metal Nanoparticles/chemistry
- Metal Nanoparticles/ultrastructure
- Microscopy, Atomic Force
- Microscopy, Electron, Scanning
- Microscopy, Electron, Transmission
- Models, Molecular
- Protein Aggregates
- Protein Conformation
- Protein Denaturation
- Protein Stability
- Serum Albumin, Bovine/chemistry
- Serum Albumin, Bovine/genetics
- Serum Albumin, Bovine/ultrastructure
- Spectrometry, Fluorescence
- Spectroscopy, Fourier Transform Infrared
- Spectrum Analysis, Raman
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Affiliation(s)
- Michał Kluz
- Institute of High Pressure Physics, Polish Academy of Sciences, Warsaw, Poland
| | - Hanna Nieznańska
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Robert Dec
- Institute of High Pressure Physics, Polish Academy of Sciences, Warsaw, Poland
- Department of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Warsaw, Poland
| | - Igor Dzięcielewski
- Institute of High Pressure Physics, Polish Academy of Sciences, Warsaw, Poland
| | - Bartosz Niżyński
- Department of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Warsaw, Poland
| | - Grzegorz Ścibisz
- Department of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Warsaw, Poland
| | - Wojciech Puławski
- Institute of High Pressure Physics, Polish Academy of Sciences, Warsaw, Poland
| | - Grzegorz Staszczak
- Institute of High Pressure Physics, Polish Academy of Sciences, Warsaw, Poland
| | - Ewelina Klein
- Institute of High Pressure Physics, Polish Academy of Sciences, Warsaw, Poland
| | | | - Wojciech Dzwolak
- Institute of High Pressure Physics, Polish Academy of Sciences, Warsaw, Poland
- Department of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Warsaw, Poland
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11
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Reynoso E, Cacciari RD, Suchetti CA, Montejano HA, Biasutti MA. Influence of pH and micellar systems on the sensitized photo-oxidation of bovine serum albumin. LUMINESCENCE 2019; 34:324-333. [PMID: 30740864 DOI: 10.1002/bio.3610] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 01/03/2019] [Accepted: 01/07/2019] [Indexed: 12/24/2022]
Abstract
Photosensitized oxidation of bovine serum albumin (BSA), by using perinaphtenone as a sensitizer, has been studied at pH 7.4 and 11. The selected sensitizer does not present ground-state complexation with BSA and ensures that the mechanism is mediated by O2 (1 △g ). Strong dependence between BSA-O2 (1 △g ) photo-oxidation and the pH of the medium has been found. The relative oxygen uptake rate (v- △ O2 ) and the total quenching rate constant (kt ) values are higher at pH 11 than pH 7.4. The enhancement in the alkaline condition is due to conformational changes in the protein and the reactivity of tyrosinate anion with O2 (1 △g ). Even when the tendency with the pH in the presence of sodium dodecyl sulfate (SDS) micelles is similar to that observed in homogeneous media, an increment on the kt value is detected. This effect may be attributable to the strong interaction of BSA-SDS, which leads to the protein unfolding and could leave more exposed photo-oxidizable amino acids. A protective effect against the O2 (1 △g )-mediated photo-oxidation was observed in reverse micelles (RMs) of sodium bis(2-ethylhexyl)sulfosuccinate (AOT) by comparing the kt values obtained at W = 10 with respect to the one obtain in homogeneous media. The latter could be mainly explained by the modification in the solvent polarity. Also, another important observation was found, the internal pH inside RMs of AOT sensed through tyrosine absorption was independent of the one used for the formation of the water pool. Hence, the kt values observed at both pH, are quite similar.
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Affiliation(s)
- Eugenia Reynoso
- Departamento de Química, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Córdoba, Argentina
| | - R Daniel Cacciari
- Departamento de Química, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Córdoba, Argentina
| | - Carlos A Suchetti
- Departamento de Química, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Córdoba, Argentina
| | - Hernán A Montejano
- Departamento de Química, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Córdoba, Argentina
| | - M Alicia Biasutti
- Departamento de Química, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Córdoba, Argentina
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12
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Sahu DK, Sarkar P, Singha D, Sahu K. Protein-activated transformation of silver nanoparticles into blue and red-emitting nanoclusters. RSC Adv 2019; 9:39405-39409. [PMID: 35540637 PMCID: PMC9076107 DOI: 10.1039/c9ra06774d] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 11/23/2019] [Indexed: 12/11/2022] Open
Abstract
Protein capping can trigger nanoparticle to nanocluster transformation at elevated pH.
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Affiliation(s)
- Dillip Kumar Sahu
- Department of Chemistry
- Indian Institute of Technology Guwahati
- Guwahati 781039
- India
| | - Priyanka Sarkar
- Department of Chemistry
- Indian Institute of Technology Guwahati
- Guwahati 781039
- India
| | - Debabrata Singha
- Department of Chemistry
- Indian Institute of Technology Guwahati
- Guwahati 781039
- India
| | - Kalyanasis Sahu
- Department of Chemistry
- Indian Institute of Technology Guwahati
- Guwahati 781039
- India
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13
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Formation and characterization of self-assembled bovine serum albumin nanoparticles as chrysin delivery systems. Colloids Surf B Biointerfaces 2019; 173:43-51. [DOI: 10.1016/j.colsurfb.2018.09.046] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 08/24/2018] [Accepted: 09/20/2018] [Indexed: 12/20/2022]
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14
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Parray ZA, Ahamad S, Ahmad F, Hassan MI, Islam A. First evidence of formation of pre-molten globule state in myoglobin: A macromolecular crowding approach towards protein folding in vivo. Int J Biol Macromol 2018; 126:1288-1294. [PMID: 30586590 DOI: 10.1016/j.ijbiomac.2018.12.170] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 12/14/2018] [Accepted: 12/18/2018] [Indexed: 01/04/2023]
Abstract
Myoglobin is known to show formation of intermediate states under various environmental conditions, in spite of that, this is the first evidence of formation pre-molten globule (PMG) in myoglobin. Polyethylene glycol (PEG) of various molecular sizes shows assorted effects on different proteins. Out of too short and too long PEGs, only PEGs of optimal size interact with proteins leading to change in protein structure that form intermediate state. We are the first one to report the formation of PMG in a protein in the presence of a crowding agent. The PEG-induced intermediate state was characterized by various techniques like absorption, fluorescence, near- and far-UV circular dichroism spectroscopy, ANS binding, and dynamic light scattering measurements to be PMG. Isothermal titration calorimetry and docking studies were further carried out to delineate the mechanism of formation of PMG in myoglobin in physiological conditions. The intermediate formed due to interaction of PEG with myoglobin has physiological implications which are essential to unravel the mystery to solve the massively complicated problems involved in the proper folding of proteins in vivo. Further, outcomes from this study are expected to gain mechanistic insights on the native structure and functions of proteins under in vivo conditions.
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Affiliation(s)
- Zahoor Ahmad Parray
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Shahzaib Ahamad
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Faizan Ahmad
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Md Imtaiyaz Hassan
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Asimul Islam
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India.
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15
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Rosa da Silva CM, Chura-Chambi RM, Ramos Pereira L, Cordeiro Y, de Souza Ferreira LC, Morganti L. Association of high pressure and alkaline condition for solubilization of inclusion bodies and refolding of the NS1 protein from zika virus. BMC Biotechnol 2018; 18:78. [PMID: 30541520 PMCID: PMC6291932 DOI: 10.1186/s12896-018-0486-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 11/23/2018] [Indexed: 11/30/2022] Open
Abstract
Background Proteins in inclusion bodies (IBs) present native-like secondary structures. However, chaotropic agents at denaturing concentrations, which are widely used for IB solubilization and subsequent refolding, unfold these secondary structures. Removal of the chaotropes frequently causes reaggregation and poor recovery of bioactive proteins. High hydrostatic pressure (HHP) and alkaline pH are two conditions that, in the presence of low level of chaotropes, have been described as non-denaturing solubilization agents. In the present study we evaluated the strategy of combination of HHP and alkaline pH on the solubilization of IB using as a model an antigenic form of the zika virus (ZIKV) non-structural 1 (NS1) protein. Results Pressure-treatment (2.4 kbar) of NS1-IBs at a pH of 11.0 induced a low degree of NS1 unfolding and led to solubilization of the IBs, mainly into monomers. After dialysis at pH 8.5, NS1 was refolded and formed soluble oligomers. High (up to 68 mg/liter) NS1 concentrations were obtained by solubilization of NS1-IBs at pH 11 in the presence of arginine (Arg) with a final yield of approximately 80% of total protein content. The process proved to be efficient, quick and did not require further purification steps. Refolded NS1 preserved biological features regarding reactivity with antigen-specific antibodies, including sera of ZIKV-infected patients. The method resulted in an increase of approximately 30-fold over conventional IB solubilization-refolding methods. Conclusions The present results represent an innovative non-denaturing protein refolding process by means of the concomitant use of HHP and alkaline pH. Application of the reported method allowed the recovery of ZIKV NS1 at a condition that maintained the antigenic properties of the protein. Electronic supplementary material The online version of this article (10.1186/s12896-018-0486-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Cleide Mara Rosa da Silva
- Instituto de Pesquisas Energéticas e Nucleares, IPEN-CNEN/SP, Centro de Biotecnologia, Av. Prof. Lineu Prestes, 2242, São Paulo, 05508-000, Brazil
| | - Rosa Maria Chura-Chambi
- Instituto de Pesquisas Energéticas e Nucleares, IPEN-CNEN/SP, Centro de Biotecnologia, Av. Prof. Lineu Prestes, 2242, São Paulo, 05508-000, Brazil
| | - Lennon Ramos Pereira
- Departamento de Microbiologia, Universidade de São Paulo, Instituto de Ciências Biomédicas, Av. Prof. Lineu Prestes ,1374, São Paulo, 05508-000, Brazil
| | - Yraima Cordeiro
- Universidade Federal do Rio de Janeiro, Faculdade de Farmácia, Av. Carlos Chagas Filho 373, Rio de Janeiro, 21941-902, Brazil
| | - Luís Carlos de Souza Ferreira
- Departamento de Microbiologia, Universidade de São Paulo, Instituto de Ciências Biomédicas, Av. Prof. Lineu Prestes ,1374, São Paulo, 05508-000, Brazil
| | - Ligia Morganti
- Instituto de Pesquisas Energéticas e Nucleares, IPEN-CNEN/SP, Centro de Biotecnologia, Av. Prof. Lineu Prestes, 2242, São Paulo, 05508-000, Brazil.
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16
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Exploring the pH-Induced Functional Phase Space of Human Serum Albumin by EPR Spectroscopy. MAGNETOCHEMISTRY 2018. [DOI: 10.3390/magnetochemistry4040047] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A systematic study on the self-assembled solution system of human serum albumin (HSA) and paramagnetic doxyl stearic acid (5-DSA and 16-DSA) ligands is reported covering the broad pH range 0.7–12.9, mainly using electron paramagnetic resonance (EPR) methods. It is tested to which extent the pH-induced conformational isomers of HSA reveal themselves in continuous wave (CW) EPR spectra from this spin probing approach in comparison to an established spin-labeling strategy utilizing 3-maleimido proxyl (5-MSL). Most analyses are conducted on empirical levels with robust strategies that allow for the detection of dynamic changes of ligand, as well as protein. Special emphasis has been placed on the EPR spectroscopic detection of a molten globule (MG) state of HSA that is typically found by the fluorescent probe 8-Anilino- naphthalene-1-sulfonic acid (ANS). Moreover, four-pulse double electron-electron resonance (DEER) experiments are conducted and substantiated with dynamic light scattering (DLS) data to determine changes in the solution shape of HSA with pH. All results are ultimately combined in a detailed scheme that describes the pH-induced functional phase space of HSA.
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Chura-Chambi RM, Fraga TR, da Silva LB, Yamamoto BB, Isaac L, Barbosa AS, Morganti L. Leptospira interrogans thermolysin refolded at high pressure and alkaline pH displays proteolytic activity against complement C3. ACTA ACUST UNITED AC 2018; 19:e00266. [PMID: 29992100 PMCID: PMC6036645 DOI: 10.1016/j.btre.2018.e00266] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 05/23/2018] [Accepted: 06/16/2018] [Indexed: 11/30/2022]
Abstract
Enzymes from the thermolysin family are crucial factors in the pathogenesis of several diseases caused by bacteria and are potential targets for therapeutic interventions. Thermolysin encoded by the gene LIC13322 of the causative agent of leptospirosis, Leptospira interrogans, was shown to cleave proteins from the Complement System. However, the production of this recombinant protein using traditional refolding processes with high levels of denaturing reagents for thermolysin inclusion bodies (TL-IBs) solubilization results in poor recovery and low proteolytic activity probably due to improper refolding of the protein. Based on the assumption that leptospiral proteases play a crucial role during infection, the aim of this work was to obtain a functional recombinant thermolysin for future studies on the role of these metalloproteases on leptospiral infection. The association of high hydrostatic pressure (HHP) and alkaline pH was utilized for thermolysin refolding. Incubation of a suspension of TL-IBs at HHP and a pH of 11.0 is non-denaturing but effective for thermolysin solubilization. Soluble protein does not reaggregate by dialysis to pH 8.0. A volumetric yield of 46 mg thermolysin/L of bacterial culture and a yield of near 100% in relation to the total thermolysin present in TL-IBs were obtained. SEC-purified thermolysin suffers fragmentation, likely due to autoproteolysis and presents proteolytic activity against complement C3 α-chain, possibly by a generation of a C3b-like molecule. The proteolytic activity of thermolysin against C3 was time and dose-dependent. The experience gained in this study shall help to establish efficient HHP-based processes for refolding of bioactive proteins from IBs.
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Affiliation(s)
- Rosa Maria Chura-Chambi
- Instituto de Pesquisas Energéticas e Nucleares IPEN-CNEN/SP, Centro de Biotecnologia, Av. Prof. Lineu Prestes, 2242, CEP 05508-000, São Paulo, SP, Brazil
| | - Tatiana Rodrigues Fraga
- Instituto de Ciências Biomédicas, Universidade de São Paulo, Departamento de Imunologia, Av. Prof. Lineu Prestes, 1374, CEP 05508-900, São Paulo, SP, Brazil
| | - Ludmila Bezerra da Silva
- Instituto Butantan, Laboratório de Bacteriologia, Av. Vital Brasil, 1500, CEP 05503-900, São Paulo, SP, Brazil
| | - Bruno Bernardi Yamamoto
- Instituto Butantan, Laboratório de Bacteriologia, Av. Vital Brasil, 1500, CEP 05503-900, São Paulo, SP, Brazil
| | - Lourdes Isaac
- Instituto de Ciências Biomédicas, Universidade de São Paulo, Departamento de Imunologia, Av. Prof. Lineu Prestes, 1374, CEP 05508-900, São Paulo, SP, Brazil
| | - Angela Silva Barbosa
- Instituto Butantan, Laboratório de Bacteriologia, Av. Vital Brasil, 1500, CEP 05503-900, São Paulo, SP, Brazil
| | - Ligia Morganti
- Instituto de Pesquisas Energéticas e Nucleares IPEN-CNEN/SP, Centro de Biotecnologia, Av. Prof. Lineu Prestes, 2242, CEP 05508-000, São Paulo, SP, Brazil
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18
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Sharma A, Chaudhuri TK. Physicochemical characterization of E. coli -derived human serum albumin and its comparison with the human plasma counterpart reveals it as a promising biosimilar. J Biotechnol 2018. [DOI: 10.1016/j.jbiotec.2018.03.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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19
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Famelart MH, Schong E, Croguennec T. Dry heating a freeze-dried whey protein powder: Formation of microparticles at pH 9.5. J FOOD ENG 2018. [DOI: 10.1016/j.jfoodeng.2017.12.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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20
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Vlasenkova MI, Dolinina ES, Parfenyuk EV. Preparation of mesoporous silica microparticles by sol-gel/emulsion route for protein release. Pharm Dev Technol 2018; 24:243-252. [PMID: 29583055 DOI: 10.1080/10837450.2018.1457051] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Encapsulation of therapeutic proteins into particles from appropriate material can improve both stability and delivery of the drugs, and the obtained particles can serve as a platform for development of their new oral formulations. The main goal of this work was development of sol-gel/emulsion method for preparation of silica microcapsules capable of controlled release of encapsulated protein without loss of its native structure. For this purpose, the reported in literature direct sol-gel/W/O/W emulsion method of protein encapsulation was used with some modifications, because the original method did not allow to prepare silica microcapsules capable for protein release. The particles were synthesized using sodium silicate and tetraethoxysilane as silica precursors and different compositions of oil phase. In vitro kinetics of bovine serum albumin (BSA) release in buffer (pH 7.4) was studied by Fourier transform infrared (FTIR) and fluorescence spectrometry, respectively. Structural state of encapsulated BSA and after release was evaluated. It was found that the synthesis conditions influenced substantially the porous structure of the unloaded silica particles, release properties of the BSA-loaded silica particles and structural state of the encapsulated and released protein. The modified synthesis conditions made it possible to obtain the silica particles capable of controlled release of the protein during a week without loss of the protein native structure.
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Affiliation(s)
- Mariya I Vlasenkova
- a Laboratory of Chemistry of Hybrid Nanomaterials and Supramolecular Systems , G.A. Krestov Institute of Solution Chemistry of Russian Academy of Sciences , Ivanovo , Russian Federation
| | - Ekaterina S Dolinina
- a Laboratory of Chemistry of Hybrid Nanomaterials and Supramolecular Systems , G.A. Krestov Institute of Solution Chemistry of Russian Academy of Sciences , Ivanovo , Russian Federation
| | - Elena V Parfenyuk
- a Laboratory of Chemistry of Hybrid Nanomaterials and Supramolecular Systems , G.A. Krestov Institute of Solution Chemistry of Russian Academy of Sciences , Ivanovo , Russian Federation
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21
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Interactions between epinastine and human serum albumin: Investigation by fluorescence, UV–vis, FT–IR, CD, lifetime measurement and molecular docking. J Mol Struct 2017. [DOI: 10.1016/j.molstruc.2016.12.066] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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22
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Wang Z, Zhao Q, Cui M, Pang S, Wang J, Liu Y, Xie L. Probing Temperature- and pH-Dependent Binding between Quantum Dots and Bovine Serum Albumin by Fluorescence Correlation Spectroscopy. NANOMATERIALS (BASEL, SWITZERLAND) 2017; 7:E93. [PMID: 28441351 PMCID: PMC5449974 DOI: 10.3390/nano7050093] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 04/15/2017] [Accepted: 04/21/2017] [Indexed: 12/25/2022]
Abstract
Luminescent quantum dots (QDs) with unique optical properties have potential applications in bio-imaging. The interaction between QDs and bio-molecules is important to the biological effect of QDs in vivo. In this paper, we have employed fluorescence correlation spectroscopy (FCS) to probe the temperature- and pH-dependent interactions between CdSe QDs with carboxyl (QDs-COOH) and bovine serum albumin (BSA) in buffer solutions. The results have shown that microscopic dissociation constant K'D is in the range of (1.5 ± 0.2) × 10-5 to (8.6 ± 0.1) × 10-7 M, the Hill coefficient n is from 0.4 to 2.3, and the protein corona thickness is from 3.0 to 9.4 nm. Variable-temperature measurements have shown both negative values of ∆H and ∆S for BSA adsorption on QDs-COOH, while pH has a profound effect on the adsorption. Additional, FCS measurement QDs-COOH and proteins in whole mice serum and plasma samples has also been conducted. Finally, simulation results have shown four favored QD binding sites in BSA.
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Affiliation(s)
- Zonghua Wang
- Laboratory of Fiber Materials and Modern Textile, The Growing Base for State Key Laboratory, College of Chemistry and Chemical Engineering, Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials, Collaborative Innovation Center for Marine Biomass Fiber Materials and Textiles, Qingdao University, Qingdao 266071, China.
| | - Qiyan Zhao
- Laboratory of Fiber Materials and Modern Textile, The Growing Base for State Key Laboratory, College of Chemistry and Chemical Engineering, Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials, Collaborative Innovation Center for Marine Biomass Fiber Materials and Textiles, Qingdao University, Qingdao 266071, China.
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China.
- Laboratory for Biological Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology, Beijing 100190, China.
| | - Menghua Cui
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China.
- University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Shichao Pang
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Jingfang Wang
- Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Ying Liu
- Laboratory for Biological Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology, Beijing 100190, China.
| | - Liming Xie
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China.
- University of Chinese Academy of Sciences, Beijing 100049, China.
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23
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Molodenskiy D, Shirshin E, Tikhonova T, Gruzinov A, Peters G, Spinozzi F. Thermally induced conformational changes and protein–protein interactions of bovine serum albumin in aqueous solution under different pH and ionic strengths as revealed by SAXS measurements. Phys Chem Chem Phys 2017. [DOI: 10.1039/c6cp08809k] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Temperature-induced oligomerization of albumin before and after protein melting was studied using SAXS and interpreted in terms of interaction potential.
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Affiliation(s)
| | - Evgeny Shirshin
- Department of Physics
- M.V. Lomonosov Moscow State University
- Moscow
- Russia
| | - Tatiana Tikhonova
- International Laser Center
- M.V. Lomonosov Moscow State University
- Moscow
- Russia
| | | | - Georgy Peters
- National Research Centre “Kurchatov Institute”
- Moscow
- Russia
| | - Francesco Spinozzi
- Università Politecnica delle Marche
- Dipartimento di Scienze della Vita e dell'Ambiente
- Ancona
- Italy
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24
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Chandel TI, Rabbani G, Khan M, Zaman M, Alam P, E. Shahein Y, Hasan Khan R. Binding of anti-cardiovascular drug to serum albumin: an insight in the light of spectroscopic and computational approaches. J Biomol Struct Dyn 2016; 36:54-67. [DOI: 10.1080/07391102.2016.1266968] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Tajalli Ilm Chandel
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
| | - Gulam Rabbani
- School of Medical Biotechnology, YeungNam University, Gyeongsan, Republic of Korea
| | - MohsinVahid Khan
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
| | - Masihuz Zaman
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
| | - Parvez Alam
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
| | - Yasser E. Shahein
- Molecular Biology Department, Genetic Engineering Division, National Research Centre, Cairo, Egypt
| | - Rizwan Hasan Khan
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
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25
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Othman M, Aschi A, Gharbi A. Polyacrylic acids–bovine serum albumin complexation: Structure and dynamics. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2016; 58:316-23. [DOI: 10.1016/j.msec.2015.08.057] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 08/23/2015] [Accepted: 08/25/2015] [Indexed: 11/28/2022]
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26
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Chib R, Butler S, Raut S, Shah S, Borejdo J, Gryczynski Z, Gryczynski I. Effect of Quencher, Denaturants, Temperature and pH on the Fluorescent Properties of BSA Protected Gold Nanoclusters. JOURNAL OF LUMINESCENCE 2015; 168:62-68. [PMID: 26594061 PMCID: PMC4648288 DOI: 10.1016/j.jlumin.2015.07.030] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
In this paper, we have synthesized BSA protected gold nanoclusters (BSA Au nanocluster) and studied the effect of quencher, protein denaturant, pH and temperature on the fluorescence properties of the tryptophan molecule of the BSA Au nanocluster and native BSA. We have also studied their effect on the peak emission of BSA Au nanoclusters (650 nm). The phtophysical characterization of a newly developed fluorophore in different environments is absolutely necessary to futher develop their biomedical and analytical applications. It was observed from our experiments that the tryptophan in BSA Au nanoclusters is better shielded from the polar environment. Tryptophan in native BSA showed a red shift in its peak emission wavelength position. Tryptophan is a highly polarity sensitive dye and a minimal change in its microenvironment can be easily observed in its photophysical properties.
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Affiliation(s)
- Rahul Chib
- Department of Cell Biology and Immunology, Center for Fluorescence Technologies and Nanomedicine, University of North Texas Health Science Center, Fort Worth, TX, 76107,USA
| | - Susan Butler
- Department of Cell Biology and Immunology, Center for Fluorescence Technologies and Nanomedicine, University of North Texas Health Science Center, Fort Worth, TX, 76107,USA
| | - Sangram Raut
- Department of Cell Biology and Immunology, Center for Fluorescence Technologies and Nanomedicine, University of North Texas Health Science Center, Fort Worth, TX, 76107,USA
- Department of Physics and Astronomy, Texas Christian University, Fort Worth, TX, 76129, USA
| | - Sunil Shah
- Department of Cell Biology and Immunology, Center for Fluorescence Technologies and Nanomedicine, University of North Texas Health Science Center, Fort Worth, TX, 76107,USA
| | - Julian Borejdo
- Department of Cell Biology and Immunology, Center for Fluorescence Technologies and Nanomedicine, University of North Texas Health Science Center, Fort Worth, TX, 76107,USA
| | - Zygmunt Gryczynski
- Department of Cell Biology and Immunology, Center for Fluorescence Technologies and Nanomedicine, University of North Texas Health Science Center, Fort Worth, TX, 76107,USA
- Department of Physics and Astronomy, Texas Christian University, Fort Worth, TX, 76129, USA
| | - Ignacy Gryczynski
- Department of Cell Biology and Immunology, Center for Fluorescence Technologies and Nanomedicine, University of North Texas Health Science Center, Fort Worth, TX, 76107,USA
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27
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Alam P, Naseem F, Abdelhameed AS, Khan RH. Effect of galactose on acid induced molten globule state of Soybean Agglutinin: Biophysical approach. J Mol Struct 2015. [DOI: 10.1016/j.molstruc.2015.05.061] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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28
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Yue HL, Hu YJ, Huang HG, Jiang S, Tu B. Development of morin-conjugated Au nanoparticles: exploring the interaction efficiency with BSA using spectroscopic methods. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 130:402-410. [PMID: 24810026 DOI: 10.1016/j.saa.2014.04.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2013] [Revised: 04/01/2014] [Accepted: 04/03/2014] [Indexed: 06/03/2023]
Abstract
In order to enhance its interaction efficiency with biomacromolecules for the usage as a therapeutic agent, we have conjugated morin, an antioxidant activity and anti-tumor drug, with citrate-coated Au nanoparticles (M-C-AuNPs). M-C-AuNPs were prepared by reducing chloroauric acid using trisodium citrate in the boiling condition, and the resulted M-C-AuNPs were characterized by UV-vis absorption spectroscopy, Transmission Electron Microscopy (TEM), X-ray diffraction (XRD) and FTIR analysis. In this article, UV-vis absorption spectroscopy in combination with fluorescence spectroscopy, and circular dichroism (CD) spectroscopy were employed to investigate the interactions between M-C-AuNPs and bovine serum albumin (BSA), C-AuNPs and BSA in a phosphate buffer at pH 7.4. By comparing the quenching constant KSV, effective quenching constant Ka, binding constant Kb and the number of binding sites n, it is clearly suggested that M-C-AuNPs could enhance the binding force of morin with BSA, which would pave the way for the design of nanotherapeutic agents with improved functionality.
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Affiliation(s)
- Hua-Li Yue
- Hubei Collaborative Innovation Center for Rare Metal Chemistry, Hubei Key Laboratory of Pollutant Analysis & Reuse Technology, Department of Chemistry, Hubei Normal University, Huangshi 435002, PR China
| | - Yan-Jun Hu
- Hubei Collaborative Innovation Center for Rare Metal Chemistry, Hubei Key Laboratory of Pollutant Analysis & Reuse Technology, Department of Chemistry, Hubei Normal University, Huangshi 435002, PR China.
| | - Hong-Gui Huang
- Hubei Collaborative Innovation Center for Rare Metal Chemistry, Hubei Key Laboratory of Pollutant Analysis & Reuse Technology, Department of Chemistry, Hubei Normal University, Huangshi 435002, PR China
| | - Shan Jiang
- Hubei Collaborative Innovation Center for Rare Metal Chemistry, Hubei Key Laboratory of Pollutant Analysis & Reuse Technology, Department of Chemistry, Hubei Normal University, Huangshi 435002, PR China
| | - Bao Tu
- Hubei Collaborative Innovation Center for Rare Metal Chemistry, Hubei Key Laboratory of Pollutant Analysis & Reuse Technology, Department of Chemistry, Hubei Normal University, Huangshi 435002, PR China
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29
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Gospodarek AM, Hiser DE, O’Connell JP, Fernandez EJ. Unfolding of a model protein on ion exchange and mixed mode chromatography surfaces. J Chromatogr A 2014; 1355:238-52. [DOI: 10.1016/j.chroma.2014.06.024] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 06/02/2014] [Accepted: 06/05/2014] [Indexed: 10/25/2022]
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30
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Saha S, Deep S. Switch in the Aggregation Pathway of Bovine Serum Albumin Mediated by Electrostatic Interactions. J Phys Chem B 2014; 118:9155-66. [DOI: 10.1021/jp502435f] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shivnetra Saha
- Department of Chemistry, Indian Institute of Technology, Delhi, Hauz-Khas, New Delhi 110016, India
| | - Shashank Deep
- Department of Chemistry, Indian Institute of Technology, Delhi, Hauz-Khas, New Delhi 110016, India
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31
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32
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Biophysical studies on the interactions of jatrorrhizine with bovine serum albumin by spectroscopic and molecular modeling methods. Mol Biol Rep 2013; 40:4397-404. [DOI: 10.1007/s11033-013-2529-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 04/29/2013] [Indexed: 01/08/2023]
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33
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Babcock JJ, Brancaleon L. Bovine serum albumin oligomers in the E- and B-forms at low protein concentration and ionic strength. Int J Biol Macromol 2013; 53:42-53. [PMID: 23148944 PMCID: PMC3605742 DOI: 10.1016/j.ijbiomac.2012.10.030] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Revised: 10/25/2012] [Accepted: 10/27/2012] [Indexed: 12/14/2022]
Abstract
The manuscript describes the study of the oligomerization process of bovine serum albumin (BSA) in two different structural monomeric forms: the extended-form (E) at pH 2.0 and the basic-form (B) at pH 9.0. The study was conducted at low protein concentration (1mg/ml) and relatively short incubation time (maximum 56 days) in order to investigate early oligomerization events rather than the formation of mature fibrils. The comparison between the two isoforms show that oligomers form much faster (∼6 days) in the E-form than in the B-form where formation of oligomers requires ∼4 weeks. The oligomers appear to be limited to a maximum of tetramers with size <30 nm. Hydrophobic interactions from exposed neutral amino acid residues in the elongated E-form are the likely cause for the quick formation of aggregates at acidic pH. We used an array of biophysical techniques for the study and determined that oligomerization occurs without further large changes in the secondary structure of the monomers. Under the conditions adopted in this study, aggregation does not seem to exceed the formation of tetramers, even though a very small amount of much larger aggregates seem to form.
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Affiliation(s)
- Jeremiah J. Babcock
- Department of Physics and Astronomy, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78242, USA
| | - Lorenzo Brancaleon
- Department of Physics and Astronomy, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78242, USA
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34
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Qadeer A, Rabbani G, Zaidi N, Ahmad E, Khan JM, Khan RH. 1-Anilino-8-naphthalene sulfonate (ANS) is not a desirable probe for determining the molten globule state of chymopapain. PLoS One 2012; 7:e50633. [PMID: 23209794 PMCID: PMC3510187 DOI: 10.1371/journal.pone.0050633] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Accepted: 10/23/2012] [Indexed: 01/22/2023] Open
Abstract
The molten globule (MG) state of proteins is widely detected through binding with 1-anilino-8-naphthalene sulphonate (ANS), a fluorescent dye. This strategy is based upon the assumption that when in molten globule state, the exposed hydrophobic clusters of protein are readily bound by the nonpolar anilino-naphthalene moiety of ANS molecules which then produce brilliant fluorescence. In this work, we explored the acid-induced unfolding pathway of chymopapain, a cysteine proteases from Carica papaya, by monitoring the conformational changes over a pH range 1.0–7.4 by circular dichroism, intrinsic fluorescence, ANS binding, acrylamide quenching, isothermal titration calorimetry (ITC) and dynamic light scattering (DLS). The spectroscopic measurements showed that although maximum ANS fluorescence intensity was observed at pH 1.0, however protein exhibited ∼80% loss of secondary structure which does not comply with the characteristics of a typical MG-state. In contrast at pH 1.5, chymopapain retains substantial amount of secondary structure, disrupted side chain interactions, increased hydrodynamic radii and nearly 30-fold increase in ANS fluorescence with respect to the native state, indicating that MG-state exists at pH 1.5 and not at pH 1.0. ITC measurements revealed that ANS molecules bound to chymopapain via hydrophobic interaction were more at pH 1.5 than at pH 1.0. However, a large number of ANS molecules were also involved in electrostatic interaction with protein at pH 1.0 which, together with hydrophobically interacted molecules, may be responsible for maximum ANS fluorescence. We conclude that maximum ANS-fluorescence alone may not be the criteria for determining the MG of chymopapain. Hence a comprehensive structural analysis of the intermediate is essentially required.
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Affiliation(s)
- Atiyatul Qadeer
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
| | - Gulam Rabbani
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
| | - Nida Zaidi
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
| | - Ejaz Ahmad
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
| | - Javed M. Khan
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
| | - Rizwan H. Khan
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
- * E-mail:
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Khan AB, Khan JM, Ali MS, Khan RH. Interaction of amphiphilic drugs with human and bovine serum albumins. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2012; 97:119-124. [PMID: 22750346 DOI: 10.1016/j.saa.2012.05.060] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Revised: 05/12/2012] [Accepted: 05/26/2012] [Indexed: 06/01/2023]
Abstract
To know the interaction of amphiphilic drugs nortriptyline hydrochloride (NOT) and promazine hydrochloride (PMZ) with serum albumins (i.e., human serum albumin (HSA) and bovine serum albumin (BSA)), techniques of UV-visible, fluorescence, and circular dichroism (CD) spectroscopies are used. The binding affinity is more in case of PMZ with both the serum albumins. The quenching rate constant (k(q)) values suggest a static quenching process for all the drug-serum albumin interactions. The UV-visible results show that the change in protein conformation of PMZ-serum albumin interactions are more prominent as compared to NOT-serum albumin interactions. The CD results also explain the conformational changes in the serum albumins on binding with the drugs. The increment in %α-helical structure is slightly more for drug-BSA complexes as compared to drug-HSA complexes.
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Affiliation(s)
- Abbul Bashar Khan
- Department of Chemistry, Aligarh Muslim University, Aligarh 202002, India
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Effect of polyethylene glycols on the alkaline-induced molten globule intermediate of bovine serum albumin. Int J Biol Macromol 2012; 51:97-104. [PMID: 22561740 DOI: 10.1016/j.ijbiomac.2012.04.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Revised: 12/22/2011] [Accepted: 04/20/2012] [Indexed: 01/13/2023]
Abstract
In the present study, the formation of one molten globule-like unfolding intermediate of bovine serum albumin (BSA) at pH 11.2 has been established with the help of circular dichroism (CD) spectra, fluorescence spectroscopy and 'phase diagram' approach. Additionally, we have shown the conformational changes occurring in the pH 11.2 intermediate of BSA when it was exposed to different molecular weight polyethylene glycols (PEGs) at varying concentrations. When the pH 11.2 intermediate of BSA was treated by PEG 400 there was induction of secondary and non-native tertiary contacts. In case of PEG 8000 and PEG 20,000, the loss in secondary as well as tertiary structure was observed. PEG 8000 and 20,000 altered the conformation of the pH 11.2 intermediate and resulted in its transition to another intermediate state in which the hydrophobic patches were inaccessible.
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Norberto DR, Vieira JM, de Souza AR, Bispo JAC, Bonafe CFS. Pressure- and Urea-Induced Denaturation of Bovine Serum Albumin: Considerations about Protein Heterogeneity. ACTA ACUST UNITED AC 2012. [DOI: 10.4236/ojbiphy.2012.21002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Spectroscopic approach of the interaction study of amphiphilic drugs with the serum albumins. Colloids Surf B Biointerfaces 2011; 87:447-53. [DOI: 10.1016/j.colsurfb.2011.06.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2011] [Accepted: 06/04/2011] [Indexed: 11/20/2022]
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Biçer E, Özdemir S. Voltammetric and spectroscopic studies on the interaction of tilmicosin with bovine serum albumin at different pHs. J Electroanal Chem (Lausanne) 2011. [DOI: 10.1016/j.jelechem.2011.04.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Cheong KW, Leow TC, Rahman RNZRA, Basri M, Rahman MBA, Salleh AB. Reductive Alkylation Causes the Formation of a Molten Globule-Like Intermediate Structure in Geobacillus zalihae Strain T1 Thermostable Lipase. Appl Biochem Biotechnol 2010; 164:362-75. [DOI: 10.1007/s12010-010-9140-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2010] [Accepted: 11/29/2010] [Indexed: 11/28/2022]
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Specific molten globule conformation of stem bromelain at alkaline pH. Arch Biochem Biophys 2010; 499:26-31. [DOI: 10.1016/j.abb.2010.05.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2010] [Revised: 05/05/2010] [Accepted: 05/05/2010] [Indexed: 11/20/2022]
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Sen P, Ahmad B, Rabbani G, Khan RH. 2,2,2-Trifluroethanol induces simultaneous increase in α-helicity and aggregation in alkaline unfolded state of bovine serum albumin. Int J Biol Macromol 2010; 46:250-4. [DOI: 10.1016/j.ijbiomac.2009.12.013] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Revised: 12/24/2009] [Accepted: 12/24/2009] [Indexed: 11/30/2022]
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Bose D, Sarkar D, Chattopadhyay N. Probing the binding interaction of a phenazinium dye with serum transport proteins: a combined fluorometric and circular dichroism study. Photochem Photobiol 2010; 86:538-44. [PMID: 20113428 DOI: 10.1111/j.1751-1097.2009.00688.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In the present investigation, an attempt has been made to study the interaction of phenosafranin (PSF), a cationic phenazinium dye with the transport proteins, bovine serum albumin (BSA) and human serum albumin (HSA), employing steady-state and time-resolved fluorometric and circular dichroism (CD) techniques. The photophysical properties of the dye are altered on binding with the serum proteins. An explicit study with respect to the modification of the fluorescence and fluorescence anisotropy upon binding, effect of denaturant, fluorescence lifetime and CD measurements reveal that the dye binds to both BSA and HSA with almost the same affinity. Far-UV CD spectra indicate a decrease in the percentage of alpha-helicity only for BSA upon binding with the probe. Near-UV CD responses indicate an alteration in the tertiary structure of both the transport proteins because of binding.
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Affiliation(s)
- Debosreeta Bose
- Department of Chemistry, Jadavpur University, Kolkata, India
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Qu P, Lu H, Yan S, Lu Z. Influences of cationic, anionic, and nonionic surfactants on alkaline-induced intermediate of bovine serum albumin. Int J Biol Macromol 2010; 46:91-9. [DOI: 10.1016/j.ijbiomac.2009.10.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2009] [Revised: 10/12/2009] [Accepted: 10/17/2009] [Indexed: 10/20/2022]
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Qu P, Lu H, Yan S, Zhou D, Lu Z. Investigations of effects of environmental factors in unfolding/refolding pathway of proteins on 8-anilino-1-naphthalene-sulfonic acid (ANS) fluorescence. J Mol Struct 2009. [DOI: 10.1016/j.molstruc.2009.07.037] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Novel binding studies of human serum albumin with trans-feruloyl maslinic acid. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2009; 95:81-8. [PMID: 19230701 DOI: 10.1016/j.jphotobiol.2009.01.002] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2008] [Revised: 12/17/2008] [Accepted: 01/09/2009] [Indexed: 01/09/2023]
Abstract
Human serum albumin (HSA) is a predominant protein in the blood. Most drugs can bind to HSA and be transported to target locations of the body. For this study, we have extracted 3-trans-feruloyl maslinic acid (FMA) from the medicinal plant Tetracera asiatica, its a non-fluorescent derivative have potent anti-cancer, anti-HIV, anti-diabetic, and anti-inflammatory activities. The binding constant of the compound with HSA, calculated from fluorescence data, was found as K(FMA)=1.42+/-0.01 x 10(8) M(-1), which corresponds to 10.9 kcal M(-1) of free energy. Furthermore, microTOF-Q mass spectrometry data showed binding of FMA at nanomolar concentrations of FMA to free HSA. The study detected a mass increase from 66,560 Da (free HSA) to 67,919 Da (HSA+drug). This indicated a strong binding of FMA to HSA, resulting in an increase of the protein's absorbance and fluorescence. The secondary structure of HSA+FMA (0.1 mM) complexes showed the protein secondary structure became partially unfolded upon interaction of FMA with HSA, as well as indicating that HSA-FMA complexes were formed. Docking experiments uncovered the binding mode of FMA in HSA molecule. It was found that FMA binds strongly in different places with hydrogen bonding at IB domain of Arg 114, Leu 115 and Asp 173.
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Subramanyam R, Gollapudi A, Bonigala P, Chinnaboina M, Amooru DG. Betulinic acid binding to human serum albumin: a study of protein conformation and binding affinity. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2008; 94:8-12. [PMID: 18945624 DOI: 10.1016/j.jphotobiol.2008.09.002] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2008] [Revised: 09/03/2008] [Accepted: 09/08/2008] [Indexed: 10/21/2022]
Abstract
Betulinic acid (BA) has anti cancer and anti-HIV activity and has been proved to be therapeutically effective against cancerous and HIV-infected cells. Human serum albumin (HSA) is the predominant protein in the blood. Most drugs that bind to HSA will be transported to other parts of the body. Using micro TOF-Q mass spectrometry, we have shown, for the first time that BA isolated from a plant (Tephrosia calophylla) binds to HSA. The binding constant of BA to HSA was calculated from fluorescence data and found to be K(BA)=1.685+/-0.01 x 10(6) M(-1), indicating a strong binding affinity. The secondary structure of the HSA-BA complex was determined by circular dichroism. The results indicate that the HSA in this complex is partially unfolded. Further, binding of BA at nanomolar concentrations of BA to free HSA was detected using micro TOF-Q mass spectrometry. The study revealed a mass increase from 65199 Da (free HSA) to 65643 Da (HSA+drug), where the additional mass of 444 Da was due to bound BA. Based on the results of this study, it is suggested that micro TOF-Q mass spectrometry is useful technique for drug binding studies.
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Affiliation(s)
- Rajagopal Subramanyam
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India.
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