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Sookai S, Akerman MP, Munro OQ. Chiral Au(III) chelates exhibit unique NCI-60 cytotoxicity profiles and interactions with human serum albumin. Dalton Trans 2024; 53:5089-5104. [PMID: 38375922 DOI: 10.1039/d3dt04024k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2024]
Abstract
Au(III) bis(pyrrolide-imine) chelates are emerging as a class of versatile, efficacious metallodrug candidates. Here, we synthesised two enantiopure chiral ligands H2L1 and H2L2 (tetradentate cyclohexane-1,2-diamine-bridged bis(pyrrole-imine) derivatives). Metallation of the ligands with Au(III) afforded the chiral cationic complexes AuL1 and AuL2. The in vitro cytotoxicities of AuL1 and AuL2 determined in the NCI-60 single-dose drug screen were 56.5% and 89.1%, respectively. AuL1 was subsequently selected for a five-dose NCI-60 screen, attaining GI50, IC50, and LC50 values of 4.7, 9.3 and 39.8 μM, respectively. Hierarchical cluster analysis of the NCI-60 data indicated that the profile for AuL1 was similar to that of vinblastine sulfate, a microtubule-targeting vinca alkaloid. Reactions of AuL1 with glutathione (GSH) in vitro confirmed its susceptibility to reduction, Au(III) → Au(I), by intracellular thiols. Because human serum albumin (HSA) is responsible for transporting clinically deployed and investigational drugs, we studied the uptake of AuL1 and AuL2 by HSA to delineate how chirality impacts their protein-binding affinity. Steady-state fluorescence quenching data acquired on the native protein and data from site-specific probes showed that the compounds bind at sites close enough to Trp-214 (subdomain IIA) of HSA to quench the fluorophore. The bimolecular quenching rate constants, Kq, were ca. 102 times higher than the maximum diffusion-controlled collision constant of a biomolecule in water (1010 M-1 s-1), confirming that static fluorescence quenching was the dominant mechanism. The Stern-Volmer constants, KSV, were ∼104 M-1 at 37 °C, while the affinity constants, Ka (37 °C), measured ∼2.1 × 104 M-1 (AuL1) and ∼1.2 × 104 M-1 (AuL2) for enthalpy-driven ligand uptake targeting Sudlow's site I. Although far- and near-UV CD spectroscopy indicated that both complexes minimally perturb the secondary and tertiary structure of HSA, substantial shifts in the CD spectra were recorded for both protein-bound ligands. This study highlights the role of chirality in determining the cytotoxicity profiles and protein binding behaviour of enantiomeric Au(III) chelates.
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Affiliation(s)
- Sheldon Sookai
- Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, PO WITS 2050, Johannesburg, South Africa.
| | - Matthew P Akerman
- School of Chemistry and Physics, University of KwaZulu-Natal, Pietermaritzburg, 3201, South Africa
| | - Orde Q Munro
- Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, PO WITS 2050, Johannesburg, South Africa.
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds LS2 9JT, UK
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2
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Sookai S, Bracken ML, Nowakowska M. Spectroscopic and Computational pH Study of Ni II and Pd II Pyrrole-Imine Chelates with Human Serum Albumin. Molecules 2023; 28:7466. [PMID: 38005188 PMCID: PMC10673405 DOI: 10.3390/molecules28227466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 10/25/2023] [Accepted: 11/03/2023] [Indexed: 11/26/2023] Open
Abstract
Human serum albumin (HSA) efficiently transports drugs in vivo: most are organic. Therefore, it is important to delineate the binding of small molecules to HSA. Here, for the first time, we show that HSA binding depends not only on the identity of the d8 metal ion, NiII or PdII, of their complexes with bis(pyrrole-imine), H2PrPyrr, but on the pH level as well. Fluorescence quenching data for native and probe-bound HSA showed that sites close to Trp-214 (subdomain IIA) are targeted. The affinity constants, Ka, ranged from ~3.5 × 103 M-1 to ~1 × 106 M-1 at 37 °C, following the order Pd(PrPyrr) > Ni(PrPyrr) at pH levels of 4 and 7; but Ni(PrPyrr) > Pd(PrPyrr) at a pH level of 9. Ligand uptake is enthalpically driven, dependent mainly on London dispersion forces. The induced CD spectra for the protein-bound ligands could be simulated by hybrid QM:MM TD-DFT methods, allowing us to delineate the binding site of the ligands and to prove that the metal chelates neither decompose nor demetallate after uptake by HSA. The transport and delivery of the metal chelates by HSA in vivo is therefore feasible.
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Affiliation(s)
- Sheldon Sookai
- Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Johannesburg PO WITS 2050, South Africa; (M.L.B.); (M.N.)
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3
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Sookai S, Munro OQ. Spectroscopic and computational study of the interaction of Pt(II) pyrrole-imine chelates with human serum albumin. Dalton Trans 2023; 52:14774-14789. [PMID: 37698009 DOI: 10.1039/d3dt02039h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/13/2023]
Abstract
Three bis(pyrrolide-imine) Pt(II) chelates were synthesised and characterized with different bridging alkyl groups, specifically 2-hydroxypropyl (1), 2,2-dimethylpropyl (2), and 1,2-(S,S)-(+)-cyclohexyl (3). Novel compounds 1 and 2 were analysed by single-crystal X-ray diffraction (space group P1̄). The asymmetric unit of 1 comprises three independent molecules linked by hydrogen bonds involving the OH groups, forming a trimeric supramolecular structure. The Pt(II) chelates were reacted with human serum albumin (HSA) to investigate how the ligand bound to the Pt(II) ion influences the compound's affinity for HSA. Fluorescence quenching data obtained for native HSA and HSA bound to site-specific probes (warfarin, subdomain IIA; ibuprofen, subdomain IIIA) indicated that the three Pt(II) chelates bind close enough (within ∼30 Å) to Trp-214 to quench its intrinsic fluorescence. The bimolecular quenching constant (kq) was 103-104 -fold higher than the maximum diffusion-controlled collision constant in water (1010 M s-1) at 310 K, while the affinity constants, Ka, ranged from ∼5 × 103 to ∼5 × 105 at 310 K, and followed the order 1 > 3 > 2. The reactions of 1 and 3 with HSA were enthalpically driven, while that for 2 was entropically driven. Macromolecular docking simulations (Glide XP) and binding site specificity assays employing site-specific probes and UV-vis CD spectroscopy indicated that 1 and 2 target Sudlow's site II in subdomain IIIA, minimally perturbing the tertiary structure of the protein. Well-resolved induced CD signals from 1 and 2 bound to HSA in subdomain IIIA were adequately simulated by hybrid QM:MM TD-DFT methods. We conclude that the structure of the bis(pyrrolide-imine) Pt(II) chelate measurably affects its uptake by HSA without detectable decomposition or demetallation. Such compounds could thus serve as metallodrug candidates capable of utilising an HSA-mediated cellular uptake pathway.
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Affiliation(s)
- Sheldon Sookai
- Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, PO WITS 2050, Johannesburg, South Africa.
| | - Orde Q Munro
- Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, PO WITS 2050, Johannesburg, South Africa.
- School of Chemistry University of Leeds, Woodhouse Lane, LS2 9JT, UK.
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Nemergut M, Sedláková D, Fabriciová G, Belej D, Jancura D, Sedlák E. Explanation of inconsistencies in the determination of human serum albumin thermal stability. Int J Biol Macromol 2023; 232:123379. [PMID: 36702231 DOI: 10.1016/j.ijbiomac.2023.123379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 01/15/2023] [Accepted: 01/18/2023] [Indexed: 01/24/2023]
Abstract
Thermal denaturation of human serum albumin has been the subject of many studies in recent decades, but the results of these studies are often conflicting and inconclusive. To clarify this, we combined different spectroscopic and calorimetric techniques and performed an in-depth analysis of the structural changes that occur during the thermal unfolding of different conformational forms of human serum albumin. Our results showed that the inconsistency of the results in the literature is related to the different quality of samples in different batches, methodological approaches and experimental conditions used in the studies. We confirmed that the presence of fatty acids (FAs) causes a more complex process of the thermal denaturation of human serum albumin. While the unfolding pathway of human serum albumin without FAs can be described by a two-step model, consisting of subsequent reversible and irreversible transitions, the thermal denaturation of human serum albumin with FAs appears to be a three-step process, consisting of a reversible step followed by two consecutive irreversible transitions.
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Affiliation(s)
- Michal Nemergut
- Center for Interdisciplinary Biosciences, P. J. Šafárik University in Košice, Jesenná 5, 04154 Košice, Slovakia
| | - Dagmar Sedláková
- Department of Biophysics, Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, 04001 Košice, Slovakia
| | - Gabriela Fabriciová
- Department of Biophysics, Faculty of Science, P. J. Šafárik University in Košice, Jesenná 5, 04154 Košice, Slovakia
| | - Dominik Belej
- Department of Biophysics, Faculty of Science, P. J. Šafárik University in Košice, Jesenná 5, 04154 Košice, Slovakia
| | - Daniel Jancura
- Department of Biophysics, Faculty of Science, P. J. Šafárik University in Košice, Jesenná 5, 04154 Košice, Slovakia
| | - Erik Sedlák
- Center for Interdisciplinary Biosciences, P. J. Šafárik University in Košice, Jesenná 5, 04154 Košice, Slovakia; Department of Biochemistry, Faculty of Science, P. J. Šafárik University in Košice, Moyzesova 11, 04154 Košice, Slovakia.
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Poorani TR, Ramya C, Manohar R. Molecular docking study on europium nanoparticles and mussel adhesive protein for effective detection of latent fingerprints. Biomarkers 2023; 28:32-64. [PMID: 36345920 DOI: 10.1080/1354750x.2022.2145495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Background: Reflecting on the difficulty of finding the evidence of latent fingerprints on wet and rough surfaces, scientists need to visualise those fingermarks without any background interference and stable adhesion of visualising material over the fingermark residues.Objective: To stabilize the interaction with the fingermarks, the synthesized nanoparticles were conjugated with a highly adhesive biopolymer, Mussel Adhesive Protein (MAP) which can effectively interact with fingerprint deposits.Material and Methods: Rare earth metal, europium oxide and nanoparticles were used as a visualisation material to get high contrast and reduced background interference-based fingerprints. To stabilise the interaction with the fingermarks, the synthesised nanoparticles were conjugated with highly adhesive biopolymer, Mussel Adhesive Protein (MAP) which can effectively interacts with fingerprint deposits. A molecular docking study was done using Auto-Dock to find the binding affinity between the metal nanoparticle and the protein. Further, the stability of the bioconjugated with fingerprint residues was analysed by protein-protein interaction study through patch dock and PDB Sum.Results: The docking analysis between europium and nanoparticles with MAP was found to be -8.77 kcal/mol and -47.49 kcal/mol respectively. Protein-protein interaction studies showed a highest affinity for dermcidin and keratin with a binding affinity of -16.76 kcal/mol and -24.76 kcal/mol respectively.Conclusions: The docking studies showed an efficient interaction between the synthesised molecules and the fingermark residues. Results of these interaction studies proved that this bio-conjugated complex can be explored for efficient visualisation of low intensified fingermarks.
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Affiliation(s)
- T R Poorani
- Department of Electronics and Communication Engineering, PSG College of Technology, Coimbatore, Tamil Nadu, India
| | - C Ramya
- Department of Electronics and Communication Engineering, PSG College of Technology, Coimbatore, Tamil Nadu, India
| | - Ramya Manohar
- Department of Biotechnology, Manipal Institute of Technology Bengaluru, Manipal Academy of Higher Education, Manipal, India
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Naz F, Khan I, Islam A, Khan LA. Interaction of fungal lipase with potential phytotherapeutics. PLoS One 2022; 17:e0264460. [PMID: 35617167 PMCID: PMC9135303 DOI: 10.1371/journal.pone.0264460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 05/09/2022] [Indexed: 12/02/2022] Open
Abstract
Interaction of thymol, carvacrol and linalool with fungal lipase and Human Serum Albumin (HSA) have been investigated employing UV-Vis spectroscopy Fluorescence and Circular dichroism spectroscopy (CD) along with docking studies. Thymol, carvacrol and linalool displayed approximately 50% inhibition at 1.5 mmol/litre concentrations using para-nitrophenyl palmitate (pNPP). UV-Vis spectroscopy give evidence of the formation of lipase-linalool, lipase-carvacrol and lipase—thymol complex at the ground state. Three molecules also showed complex formation with HSA at the ground state. Fluorescence spectroscopy shows strong binding of lipase to thymol (Ka of 2.6 x 109 M-1) as compared to carvacrol (4.66 x 107 M-1) and linalool (5.3 x 103 M-1). Number of binding sites showing stoichiometry of association process on lipase is found to be 2.52 (thymol) compared to 2.04 (carvacrol) and 1.12 (linalool). Secondary structure analysis by CD spectroscopy results, following 24 hours incubation at 25°C, with thymol, carvacrol and linalool revealed decrease in negative ellipticity for lipase indicating loss in helical structure as compared with the native protein. The lowering in negative ellipticity was in the order of thymol > carvacrol > linalool. Fluorescence spectra following binding of all three molecules with HSA caused blue shift which suggests the compaction of the HSA structure. Association constant of thymol and HSA is 9.6 x 108 M-1 which along with ‘n’ value of 2.41 suggests strong association and stable complex formation, association constant for carvacrol and linalool was in range of 107 and 103 respectively. Docking results give further insight into strong binding of thymol, carvacrol and linalool with lipase having free energy of binding as -7.1 kcal/mol, -5.0 kcal/mol and -5.2 kcal/mol respectively. To conclude, fungal lipases can be attractive target for controlling their growth and pathogenicity. Employing UV-Vis, Fluorescence and Circular dichroism spectroscopy we have shown that thymol, carvacrol and linalool strongly bind and disrupt structure of fungal lipase, these three phytochemicals also bind well with HSA. Based on disruption of lipase structure and its binding nature with HSA, we concluded thymol as a best anti-lipase molecule among three molecules tested. Results of Fluorescence and CD spectroscopy taken together suggests that thymol and carvacrol are profound disrupter of lipase structure.
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Affiliation(s)
- Farheen Naz
- Department of Biosciences, Faculty of Natural Sciences, Jamia Millia Islamia, New Delhi, India
| | - Imran Khan
- Department of Computer Science, Deanship of Educational Services, Qassim University, Buraidah, Al Qassim, Saudi Arabia
| | - Asimul Islam
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
| | - Luqman Ahmad Khan
- Department of Biosciences, Faculty of Natural Sciences, Jamia Millia Islamia, New Delhi, India
- * E-mail:
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Nascimento JMD, Leão TEH, Nascimento TP, Conniff AS, Batista JMDS, Costa RMPB, Porto ALF, Leite ACL. Evaluation of the influence of temperature on the protein-tannic acid complex. Int J Biol Macromol 2021; 182:2056-2065. [PMID: 34087296 DOI: 10.1016/j.ijbiomac.2021.05.179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 05/22/2021] [Accepted: 05/26/2021] [Indexed: 01/04/2023]
Abstract
Precipitation of blood products from plasma fractionation has played a fundamental role in the industrial purification of important therapeutic products. Only a few studies have been reported by using tannins as proteins precipitant agent from whole plasma while, several conditions have been analyzed. Here, we decided to verify the effect of the temperature on the precipitation process of plasma proteins using tannic acid (TA). Plasma proteins were precipitated with tannic acid by using different temperature incubations. Subsequently, the protein-TA complex was analyzed by SDS-PAGE and quantified. In addition, the protein activity of the complex was measured after heating, as well as the structural changes of the complexes were accompanied by thermogravimetric analysis, differential scanning calorimetry and circular dichroism. In all conditions tested, tannic acid was able to precipitate without selectively separating the proteins in the mixture by using different temperatures during the precipitation process. Furthermore, the protein concentration from the plasma precipitate was not affected by different temperatures and the plasma precipitate was able to dissolve fibrin clots in vitro.
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Affiliation(s)
- Jéssica Miranda do Nascimento
- Laboratory of Research in Biotechnology and Hemoderivatives, Department of Pharmaceutical Sciences, Federal University of Pernambuco, 50670-420 Recife, Pernambuco, Brazil
| | - Talita Emanuely Henrique Leão
- Laboratory of Research in Biotechnology and Hemoderivatives, Department of Pharmaceutical Sciences, Federal University of Pernambuco, 50670-420 Recife, Pernambuco, Brazil
| | - Thiago Pajeú Nascimento
- Laboratory of Research in Biotechnology and Hemoderivatives, Department of Pharmaceutical Sciences, Federal University of Pernambuco, 50670-420 Recife, Pernambuco, Brazil; Laboratory of Bioactive Technology, Department of Morphology and Animal Physiology, Federal Rural University of Pernambuco, 52171-900 Recife, Pernambuco, Brazil
| | | | - Juanize Matias da Silva Batista
- Laboratory of Bioactive Technology, Department of Morphology and Animal Physiology, Federal Rural University of Pernambuco, 52171-900 Recife, Pernambuco, Brazil
| | - Romero Marcos Pedrosa Brandão Costa
- Laboratory of Advances in Protein Biotechnology (LABIOPROT), Institute of Biological Sciences, University of Pernambuco, Rua Arnóbio Marquês, 310 - Santo Amaro, Recife - PE, 50100-130 Recife, Pernambuco, Brazil
| | - Ana Lúcia Figueiredo Porto
- Laboratory of Bioactive Technology, Department of Morphology and Animal Physiology, Federal Rural University of Pernambuco, 52171-900 Recife, Pernambuco, Brazil
| | - Ana Cristina Lima Leite
- Laboratory of Research in Biotechnology and Hemoderivatives, Department of Pharmaceutical Sciences, Federal University of Pernambuco, 50670-420 Recife, Pernambuco, Brazil.
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Ægidius HM, Kruse L, Christensen GL, Lorentzen MP, Jørgensen NR, Moresco M, Pizza F, Plazzi G, Jennum PJ, Kornum BR. Pre-treatment of blood samples reveal normal blood hypocretin/orexin signal in narcolepsy type 1. Brain Commun 2021; 3:fcab050. [PMID: 33977264 PMCID: PMC8100001 DOI: 10.1093/braincomms/fcab050] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 02/03/2021] [Accepted: 02/08/2021] [Indexed: 12/11/2022] Open
Abstract
The hypocretin/orexin system regulates arousal through central nervous system mechanisms and plays an important role in sleep, wakefulness and energy homeostasis. It is unclear whether hypocretin peptides are also present in blood due to difficulties in measuring reliable and reproducible levels of the peptides in blood samples. Lack of hypocretin signalling causes the sleep disorder narcolepsy type 1, and low concentration of cerebrospinal fluid hypocretin-1/orexin-A peptide is a hallmark of the disease. This measurement has high diagnostic value, but performing a lumbar puncture is not without discomfort and possible complications for the patient. A blood-based test to assess hypocretin-1 deficiency would therefore be of obvious benefit. We here demonstrate that heating plasma or serum samples to 65°C for 30 min at pH 8 significantly increases hypocretin-1 immunoreactivity enabling stable and reproducible measurement of hypocretin-1 in blood samples. Specificity of the signal was verified by high-performance liquid chromatography and by measuring blood samples from mice lacking hypocretin. Unspecific background signal in the assay was high. Using our method, we show that hypocretin-1 immunoreactivity in blood samples from narcolepsy type 1 patients does not differ from the levels detected in control samples. The data presented here suggest that hypocretin-1 is present in the blood stream in the low picograms per millilitres range and that peripheral hypocretin-1 concentrations are unchanged in narcolepsy type 1.
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Affiliation(s)
- Helene M Ægidius
- Department of Neuroscience, University of Copenhagen, 2200 Copenhagen N, Denmark
| | - Lars Kruse
- Department of Clinical Biochemistry, Rigshospitalet, 2600 Glostrup, Denmark
| | | | - Marc P Lorentzen
- Department of Clinical Biochemistry, Rigshospitalet, 2600 Glostrup, Denmark
| | - Niklas R Jørgensen
- Department of Clinical Biochemistry, Rigshospitalet, 2600 Glostrup, Denmark
| | - Monica Moresco
- Istituto delle Scienze Neurologiche, Ospedale Bellaria, IRCCS Bologna, 40139 Bologna, Italy
| | - Fabio Pizza
- Istituto delle Scienze Neurologiche, Ospedale Bellaria, IRCCS Bologna, 40139 Bologna, Italy.,Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, 40126 Bologna, Italy
| | - Giuseppe Plazzi
- Istituto delle Scienze Neurologiche, Ospedale Bellaria, IRCCS Bologna, 40139 Bologna, Italy.,Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio-Emilia, 41121 Modena, Italy
| | - Poul J Jennum
- Department of Clinical Neurophysiology, Danish Center for Sleep Medicine, Rigshospitalet, 2600 Glostrup, Denmark
| | - Birgitte R Kornum
- Department of Neuroscience, University of Copenhagen, 2200 Copenhagen N, Denmark
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Fluorescence correlation spectroscopy as a tool to investigate the directionality of proteolysis. Int J Biol Macromol 2020; 164:2524-2534. [DOI: 10.1016/j.ijbiomac.2020.08.103] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 07/31/2020] [Accepted: 08/11/2020] [Indexed: 11/21/2022]
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10
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Liu S, Jiang X, Tian X, Wang Z, Xing Z, Chen J, Zhang J, Wang C, Dong L. A method to measure the denatured proteins in the corona of nanoparticles based on the specific adsorption of Hsp90ab1. NANOSCALE 2020; 12:15857-15868. [PMID: 32696774 DOI: 10.1039/d0nr02297g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The protein corona influences and determines the biological function of nanoparticles (NPs) in vivo. Analysis and understanding of the activities of proteins in coronas are crucial for nanobiology and nanomedicine research. Misfolded proteins in the corona of NPs theoretically exist, and a protein denaturation-related cellular response might occur in this process as well as in related diseases. The exact evaluation of protein denaturation in the corona is valuable to assess the bioactivities of NPs. Here, we found that the level of adsorbed heat shock protein 90 kDa α class B member 1 (Hsp90ab1) by the denatured protein in iron-cobalt-nickel alloy NPs (FeCoNi NPs) and iron oxide NPs (Fe3O4 NPs) was correlated with circular dichroism (CD) analysis and 1-anilinonaphthalene-8-sulfonate (ANS) analysis. The content of Hsp90ab1 in the corona could be easily analysed by western blotting (WB). Further analysis suggested that the method could precisely show the time-dependent protein denaturation on Fe3O4 NPs, as well as the influence of the size and the surface modification. More importantly, this method could be applied to other proteins, like lysozyme, other than albumin. Based on the results and the correlation analysis, incubation and detection of Hsp90ab1 in the NP-corona complex can be used as a new and feasible method to evaluate protein denaturation induced by NPs.
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Affiliation(s)
- Shang Liu
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences & Medical School, Nanjing University, 163 Xianlin Avenue, Nanjing 210093, China.
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11
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Shiraga K, Urabe M, Matsui T, Kikuchi S, Ogawa Y. Highly precise characterization of the hydration state upon thermal denaturation of human serum albumin using a 65 GHz dielectric sensor. Phys Chem Chem Phys 2020; 22:19468-19479. [PMID: 32761010 DOI: 10.1039/d0cp02265a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The biological functions of proteins depend on harmonization with hydration water surrounding them. Indeed, the dynamical transition of proteins, such as thermal denaturation, is dependent on the changes in the mobility of hydration water. However, the role of hydration water during dynamical transition is yet to be fully understood due to technical limitations in precisely characterizing the amount of hydration water. A state-of-the-art CMOS dielectric sensor consisting of 65 GHz LC resonators addressed this issue by utilizing the feature that oscillation frequency sensitively shifts in response to the complex dielectric constant at 65 GHz with extremely high precision. This study aimed to establish an analytical algorithm to derive the hydration number from the measured frequency shift and to demonstrate the transition of hydration number upon the thermal denaturation of human serum albumin. The determined hydration number in the native state drew a "global" hydration picture beyond the first solvation shell, with substantially reduced uncertainty of the hydration number (about ±1%). This allowed the detection of a rapid increase in the hydration number at about 55 °C during the heating process, which was in excellent phase with the irreversible rupture of the α-helical structure into solvent-exposed extended chains, whereas the hydration number did not trace the forward path in the subsequent cooling process. Our result indicates that the weakening of water hydrogen bonds trigger the unfolding of the protein structure first, followed by the changes in the number of hydration water as a consequence of thermal denaturation.
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Affiliation(s)
- Keiichiro Shiraga
- RIKEN Center for Integrative Medical Sciences (IMS), Tsurumi, Yokohama, Kanagawa 230-0045, Japan.
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Sharma D, Singh A, Kukreti S, Pathak M, Kaur L, Kaushik V, Ojha H. Protection by ethyl pyruvate against gamma radiation induced damage in bovine serum albumin. Int J Biol Macromol 2020; 150:1053-1060. [DOI: 10.1016/j.ijbiomac.2019.10.110] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2019] [Revised: 10/11/2019] [Accepted: 10/11/2019] [Indexed: 01/08/2023]
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Sen S, Paul BK, Guchhait N. Interaction of a sphingolipid with human serum albumin in the native, thermally denatured and chemically denatured states: Emission wavelength-dependent photophysical revelation. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.111456] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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14
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Naz F, Anis H, Hasan Z, Islam A, Khan LA. Exploration of Fungal Lipase as Direct Target of Eugenol through Spectroscopic Techniques. Protein Pept Lett 2019; 26:919-929. [PMID: 31057096 DOI: 10.2174/0929866526666190506113455] [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: 11/08/2018] [Revised: 03/13/2019] [Accepted: 04/19/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND Fungal lipase dependent processes are important for their pathogenicity. Lipases can therefore be explored as direct target of promising herbal antifungals. OBJECTIVE We explored Aspergillus niger lipase as a direct target of eugenol through spectroscopic techniques and compare results with Bovine Serum Albumin and lysozyme to comment on selectivity of eugenol towards lipase. METHODS In vitro activity assays of lipase are used to determine concentration ranges. UV-Visible, Fluorescence and Circular dichroism spectroscopy were employed to determine binding constant, stoichiometric binding sites and structural changes in Lipase, BSA and lysozyme following incubation with varying concentrations of eugenol. RESULTS In activity assays 50% inhibition of lipase was obtained at 0.913 mmoles/litre eugenol. UV-vis spectroscopy shows formation of lipase-eugenol, Bovine Serum Albumin-eugenol and lysozyme-eugenol complex well below this concentration of eugenol. Eugenol binding caused blue shift with Bovine Serum Albumin and lysozyme suggestive of compaction, and red shift with lipase. Negative ellipticity decreased with lipase but increased with Bovine Serum Albumineugenol and lysozyme-eugenol complexes suggesting loss of helical structure for lipase and compaction for Bovine Serum Albumin and lysozyme. Binding of eugenol to lipase was strong (Ka= 4.7 x 106 M-1) as compared to Bovine Serum Albumin and lysozyme. The number of stoichiometric eugenol binding sites on lipase was found to be 2 as compared to 1.37 (Bovine Serum Albumin) and 0.32 (lysozyme). Docking results also suggest strong binding of eugenol with lipase followed by Bovine Serum Albumin and lysozyme. CONCLUSION Eugenol is found to be effective inhibitor and disruptor of secondary and tertiary structure of lipase, whereas its binding to Bovine Serum Albumin and lysozyme is found to be weak and less disruptive of structures suggesting selectivity of eugenol towards lipase.
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Affiliation(s)
- Farheen Naz
- Department of Biosciences, Faculty of Natural Sciences, Jamia Millia Islamia, New Delhi 110025, India
| | - Haider Anis
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Ziaul Hasan
- Department of Biosciences, Faculty of Natural Sciences, Jamia Millia Islamia, New Delhi 110025, India
| | - Asimul Islam
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Luqman A Khan
- Department of Biosciences, Faculty of Natural Sciences, Jamia Millia Islamia, New Delhi 110025, India
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15
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Pounsamy M, Somasundaram S, Palanivel S, Balasubramani R, Chang SW, Nguyen DD, Ganesan S. A novel protease-immobilized carbon catalyst for the effective fragmentation of proteins in high-TDS wastewater generated in tanneries: Spectral and electrochemical studies. ENVIRONMENTAL RESEARCH 2019; 172:408-419. [PMID: 30826663 DOI: 10.1016/j.envres.2019.01.062] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 01/18/2019] [Accepted: 01/22/2019] [Indexed: 06/09/2023]
Abstract
The aim of this study was to degrade proteins in high-total dissolved solids (TDS)-containing wastewater produced during the soaking process in tanneries (tannery-TDS wastewater) using a halotolerant protease-assisted nanoporous carbon catalyst (STPNPAC). A halotolerant protease was obtained from the halophile, Lysinibacillus macroides, using animal fleshing as the substrate. The protease was immobilized using ethylene diamine (EDA)/glutaraldehyde functionalized nanoporous activated carbon (EGNPAC). The optimum conditions for the immobilization of protease were determined as time (120 min), pH (6), protease concentration (575-600 U/g), EGNPAC size, salinity, and temperature (30 °C). The immobilization was confirmed by FTIR, TGA-DSC, SEM, and XRD analyses. The adsorption kinetics was consistent with a pseudo first order rate constant of 1.43 × 10-2 min-1. The thermodynamic parameters (ΔG, ΔH, and ΔS) confirmed the effective immobilization of the protease onto EGNPAC. STPNAPC was found to efficiently degrade the proteins in tannery-TDS wastewater, with a complete fragmentation time of 90 min at pH 6 and 30 °C. Accordingly, the protein fragmentation was confirmed by UV-visible and UV-fluorescence spectroscopy, ESI-mass spectrometric analysis and circular dichroic studies. The formation of protein hydrolysates was confirmed by cyclic voltammetry and electrical impedance studies. BOD5: COD value, 0.426 of treated tannery-TDS wastewater may favor sequential biological treatment processes.
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Affiliation(s)
- Maharaja Pounsamy
- Advanced Materials Laboratory, Council of Scientific & Industrial Research (CSIR) Central Leather Research Institute (CLRI), Adyar, Chennai 600 020, Tamilnadu, India; Environmental Science and Engineering Division, Council of Scientific & Industrial Research (CSIR) Central Leather Research Institute (CLRI), Adyar, Chennai 600 020, Tamilnadu, India
| | - Swarnalatha Somasundaram
- Environmental Science and Engineering Division, Council of Scientific & Industrial Research (CSIR) Central Leather Research Institute (CLRI), Adyar, Chennai 600 020, Tamilnadu, India
| | - Saravanan Palanivel
- Leather Process Technology Laboratory, Council of Scientific & Industrial Research (CSIR) Central Leather Research Institute (CLRI), Adyar, Chennai 600 020, Tamilnadu, India
| | - Ravindran Balasubramani
- Department of Environmental Energy and Engineering, Kyonggi University Youngtong-Gu, Suwon, Gyeonggi-Do 16227, South Korea.
| | - Soon Woong Chang
- Department of Environmental Energy and Engineering, Kyonggi University Youngtong-Gu, Suwon, Gyeonggi-Do 16227, South Korea
| | - Dinh Duc Nguyen
- Department of Environmental Energy and Engineering, Kyonggi University Youngtong-Gu, Suwon, Gyeonggi-Do 16227, South Korea; Institute of Research and Development, Duy Tan University, Da Nang, Vietnam
| | - Sekaran Ganesan
- Environmental Science and Engineering Division, Council of Scientific & Industrial Research (CSIR) Central Leather Research Institute (CLRI), Adyar, Chennai 600 020, Tamilnadu, India.
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16
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Mohan V, Sengupta B, Das N, Banerjee I, Sen P. Domain-Specific Stabilization of Structural and Dynamic Responses of Human Serum Albumin by Sucrose. Protein Pept Lett 2019; 26:287-300. [DOI: 10.2174/0929866526666190122115702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Revised: 01/03/2019] [Accepted: 01/12/2019] [Indexed: 11/22/2022]
Abstract
Background:Human Serum Albumin (HSA) is the most abundant protein present in human blood plasma. It is a large multi-domain protein with 585 amino acid residues. Due to its importance in human body, studies on the interaction of HSA with different external agent is of vital interest. The denaturation and renaturation of HSA in presence of external agents are of particular interest as they affect the biological activity of the protein.Objective:The objective of this work is to study the domain-specific and overall structural and dynamical changes occurring to HSA in the presence of a denaturing agent, urea and a renaturing agent, sucrose.Methods:In order to carry out the domain-specific studies, HSA has been tagged using N-(7- dimethylamino-4-methylcoumarin-3-yl) iodoacetamide (DACIA) at Cys-34 of domain-I and pnitrophenyl coumarin ester (NPCE) at Tyr-411 site in domain-III, separately. Steady-state absorption, emission and solvation dynamic measurements have been carried out in order to monitor the domain-specific alteration of HSA caused by the external agents. The overall structural change of HSA have been monitored using circular dichroism spectroscopy.Results:The α-helicity of HSA was found to decrease from 65% to 11% in presence of urea and was found to further increase to 25% when sucrose is added, manifesting the denaturing and renaturing effects of urea and sucrose, respectively. The steady state studies show that domain-III is more labile towards denaturation as compared to domain-I. The presence of an intermediate state is observed during the denaturation process. The stabilization of this intermediate state in presence of sucrose is attributed as the reason for the stabilization of HSA by sucrose. From solvation dynamics studies, it could be seen that the solvation time of DACIA inside domain-I of HSA decreases and increases regularly with increasing concentrations of urea and sucrose, respectively, while in the case of NPCE-tagged domain-III, the effect of sucrose on solvation time is evident only at high concentrations of urea.Conclusion:The denaturing and renaturing effects of urea and sucrose could be clearly seen from the steady state studies and circular dichroism spectroscopy measurements. A regular change in solvation time could only be observed in the case of domain-I and not in domain-III. The results indicate that the renaturing effect of sucrose on domain-III is not very evident when protein is in its native state, but is evident in when the protein is denatured.</P>
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Affiliation(s)
- Vaisakh Mohan
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur - 208 016, UP, India
| | - Bhaswati Sengupta
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur - 208 016, UP, India
| | - Nilimesh Das
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur - 208 016, UP, India
| | - Indrani Banerjee
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur - 208 016, UP, India
| | - Pratik Sen
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur - 208 016, UP, India
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17
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Siddiqi MK, Alam P, Malik S, Majid N, Chaturvedi SK, Rajan S, Ajmal MR, Khan MV, Uversky VN, Khan RH. Stabilizing proteins to prevent conformational changes required for amyloid fibril formation. J Cell Biochem 2019; 120:2642-2656. [PMID: 30242891 DOI: 10.1002/jcb.27576] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2018] [Accepted: 08/07/2018] [Indexed: 01/24/2023]
Abstract
Amyloid fibrillation is associated with several human maladies, such as Alzheimer's, Parkinson's, Huntington's diseases, prions, amyotrophic lateral sclerosis, and type 2 diabetes diseases. Gaining insights into the mechanism of amyloid fibril formation and exploring novel approaches to fibrillation inhibition are crucial for preventing amyloid diseases. Here, we hypothesized that ligands capable of stabilizing the native state of query proteins might prevent protein unfolding, which, in turn, may reduce the propensity of proteins to form amyloid fibrils. We demonstrated the efficient inhibition of amyloid formation of the human serum albumin (HSA) (up to 85%) and human insulin (up to 80%) by a nonsteroidal anti-inflammatory drug, ibuprofen (IBFN). IBFN significantly increases the conformational stability of both HSA and insulin, as confirmed by differential scanning calorimetry (DSC). Moreover, increasing concentration of IBFN boosts its amyloid inhibitory propensity in a linear fashion by influencing the nucleation phase as assayed by thioflavin T fluorescence, transmission electron microscopy, and dynamic light scattering. Furthermore, circular dichroism analysis supported the DSC results, showing that IBFN binds to the native state of proteins and almost completely prevents their tendency to lose secondary and tertiary structures. Cell toxicity assay confirms that species formed in the presence of IBFN are less toxic to neuronal cells (SH-SY5Y). These results demonstrate the feasibility of using a small molecule to stabilize the native state of proteins, thereby preventing the amyloidogenic conformational changes, which appear to be the common link in several human amyloid diseases.
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Affiliation(s)
| | - Parvez Alam
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India.,Kususma School of Biological Sciences, Indian Institute of Technology, New Delhi, India
| | - Sadia Malik
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
| | - Nabeela Majid
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
| | | | | | - Mohd Rehan Ajmal
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
| | - Mohsin Vahid Khan
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
| | - Vladimir N Uversky
- Protein Research Group, Institute for Biological Instrumentation of the Russian Academy of Sciences, Moscow, Russia.,Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.,Department of Molecular Medicine, USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, Florida
| | - Rizwan Hasan Khan
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
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18
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Sviben D, Bertoša B, Hloušek-Kasun A, Forcic D, Halassy B, Brgles M. Investigation of the thermal shift assay and its power to predict protein and virus stabilizing conditions. J Pharm Biomed Anal 2018; 161:73-82. [DOI: 10.1016/j.jpba.2018.08.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 07/30/2018] [Accepted: 08/07/2018] [Indexed: 12/21/2022]
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19
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Scavenging of hydrated electron by HSA or Ligand/HSA adduct: Pulse radiolysis study. Radiat Phys Chem Oxf Engl 1993 2018. [DOI: 10.1016/j.radphyschem.2018.07.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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20
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Das N, Sen P. Structural, Functional, and Dynamical Responses of a Protein in a Restricted Environment Imposed by Macromolecular Crowding. Biochemistry 2018; 57:6078-6089. [DOI: 10.1021/acs.biochem.8b00599] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Nilimesh Das
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208 016, India
| | - Pratik Sen
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208 016, India
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21
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Mohan V, Sengupta B, Acharyya A, Yadav R, Das N, Sen P. Region-Specific Double Denaturation of Human Serum Albumin: Combined Effects of Temperature and GnHCl on Structural and Dynamical Responses. ACS OMEGA 2018; 3:10406-10417. [PMID: 31459168 PMCID: PMC6645044 DOI: 10.1021/acsomega.8b00967] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 08/08/2018] [Indexed: 05/30/2023]
Abstract
In this work, we have investigated the effects of denaturing agents, guanidine hydrochloride (GnHCl) and temperature, on the overall structure, domain-I, and domain-III of human serum albumin (HSA) using circular dichroism (CD) spectroscopy and steady-state, time-resolved fluorescence spectroscopy. We have tagged Cys-34 of HSA, located at domain-I, using N-(7-dimethylamino-4-methylcoumarin-3-yl)iodoacetamide and Tyr-411 of HSA, located at domain-III, using p-nitrophenyl coumarin ester, for this purpose. The CD spectroscopy studies reveal the overall denaturation of the protein. The denaturation follows the expected direction in which the protein is denatured with an increase in the concentration of GnHCl or temperature. The α-helicity of the native state of HSA was found to be 64.2%, and the minimum value of α-helicity was found to be 14.8% in the presence of 6 M GnHCl at room temperature. Steady-state emission studies were carried out on domain-I and domain-III of the protein using site-specific fluorescent tags. The degree of folding of the two domains at different combinations of temperature and GnHCl concentration was calculated and was found to follow a slightly different course of denaturation. Solvation dynamics was found to be quite different for these two domains. The domain-I of HSA has a maximum solvation time of 0.39 ns, and the solvation time tends to decrease with the action of either temperature or GnHCl. On the other hand, the domain-III of HSA showed a much higher solvation time (1.42 ns) and does not show any regular change at higher temperatures or in the presence of GnHCl. This difference could be attributed to the different microenvironment inside the protein cores of the two domains.
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22
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Biswas S, Kundu J, Mukherjee SK, Chowdhury PK. Mixed Macromolecular Crowding: A Protein and Solvent Perspective. ACS OMEGA 2018; 3:4316-4330. [PMID: 30023892 PMCID: PMC6044960 DOI: 10.1021/acsomega.7b01864] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 03/16/2018] [Indexed: 06/08/2023]
Abstract
In the living cell, biomolecules perform their respective functions in the presence of not only one type of macromolecules but rather in the presence of various macromolecules with different shapes and sizes. In this study, we have investigated the effects of five single macromolecular crowding agents, Dextran 6, Dextran 40, Dextran 70, Ficoll 70, and PEG 8000 and their binary mixtures on the modulation in the domain separation of human serum albumin using a Förster resonance energy transfer-based approach and the translational mobility of a small fluorescent probe fluorescein isothiocyanate (FITC) using fluorescence correlation spectroscopy (FCS). Our observations suggest that mixed crowding induces greater cooperativity in the domain movement as compared to the components of the mixtures. Thermodynamic analyses of the same provide evidence of crossovers from enthalpy-based interactions to effects dominated by hard-sphere potential. When compared with those obtained for individual crowders, both domain movements and FITC diffusion studies show significant deviations from ideality, with an ideal solution being considered to be that arising from the sum of the contributions of those obtained in the presence of individual crowding agents. Considering the fact that domain movements are local (on the order of a few angstroms) in nature while translational movements span much larger lengthscales, our results imply that the observed deviation from simple additivity exists at several possible levels or lengthscales in such mixtures. Moreover, the nature and the type of deviation not only depend on the identities of the components of the crowder mixtures but are also influenced by the particular face of the serum protein (either the domain I-II or the domain II-III face) that the crowders interact with, thus providing further insights into the possible existence of microheterogeneities in such solutions.
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23
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Sengupta B, Acharyya A, Sen P. Elucidation of the local dynamics of domain-III of human serum albumin over the ps-μs time regime using a new fluorescent label. Phys Chem Chem Phys 2018; 18:28548-28555. [PMID: 27711622 DOI: 10.1039/c6cp05743h] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The ps-μs dynamics of domain-III of human serum albumin (HSA) has been investigated using a new fluorescent marker selectively labeled to the Tyr-411 residue. The location of the marker has been confirmed using Förster resonance energy transfer (FRET) study. Steady state, time-resolved and single molecular level fluorescence techniques have been employed to understand the dynamics within the domain-III of HSA. It is found that solvent reorganization dynamics in domain-III is 1.7 times faster than that in domain-I. The timescale of the local rotational dynamics of domain-III is found to be 2.3 times faster than that of domain-I. Fluorescence correlation spectroscopic experiments reveal that domain-III of HSA has more conformational flexibility than domain-I. Together, the results deliver useful details of the local environment around the domain-III of HSA, which have not been explored earlier, mainly because of a lack of a suitable fluorescent marker for domain-III. The newly synthesized probe serves well as a site specific fluorescent marker for HSA, and can be used for further investigation of the ligand binding properties and enzymatic activity of domain-III of HSA.
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Affiliation(s)
- Bhaswati Sengupta
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208 016, UP, India.
| | - Arusha Acharyya
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208 016, UP, India.
| | - Pratik Sen
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208 016, UP, India.
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24
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Guglielmelli A, Rizzuti B, Guzzi R. Stereoselective and domain-specific effects of ibuprofen on the thermal stability of human serum albumin. Eur J Pharm Sci 2017; 112:122-131. [PMID: 29158196 DOI: 10.1016/j.ejps.2017.11.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2017] [Revised: 10/31/2017] [Accepted: 11/16/2017] [Indexed: 12/20/2022]
Abstract
Ibuprofen is one of the most used anti-inflammatory drugs, and it is transported in the blood by human serum albumin, a major plasmatic protein with a peculiar adaptability in the binding of several different ligands. We have characterized the interaction between albumin and ibuprofen, either in racemic mixture, or in the S(+) and R(-) enantiomeric forms, by using differential scanning calorimetry, attenuated total reflectance Fourier transform infrared spectroscopy, and molecular dynamics simulation. The results show that increasing concentrations of ibuprofen (up to sixfold drug/protein molar ratio) improve the protein resistance to thermal unfolding without altering the secondary structure. Deconvolution of the calorimetric thermal profiles at different albumin/ibuprofen molar ratios demonstrates a selective stability of the protein domains where the binding sites of the drug are localized. At the highest ibuprofen concentration, the melting temperature increased by about 10°C with respect to the drug-free protein, whereas the unfolding enthalpy maintains an almost constant value. Furthermore, the degree of protein stabilization depends upon the chirality of the drug, and the R(-) enantiomer is more effective compared to the S(+) form. The stability is supported by molecular dynamics simulations, showing that ibuprofen maintains a stable coordination in the most favorable binding sites, leading to a more compact protein structure at high temperature. The overall results attest that the binding of ibuprofen determines on albumin a stereoselective and domain-specific stabilization with a predominantly entropic character, contributing to clarify significant aspects of the molecular mechanism of protein/drug interaction.
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Affiliation(s)
- Alexa Guglielmelli
- Molecular Biophysics Laboratory, Department of Physics, University of Calabria, 87036 Rende, Italy
| | - Bruno Rizzuti
- CNR-NANOTEC, Licryl-UOS Cosenza and CEMIF.Cal, Department of Physics, University of Calabria, 87036 Rende, Italy
| | - Rita Guzzi
- Molecular Biophysics Laboratory, Department of Physics, University of Calabria, 87036 Rende, Italy.
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25
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Kabir MZ, Ghani H, Mohamad SB, Alias Z, Tayyab S. Interactive association between RhoA transcriptional signaling inhibitor, CCG1423 and human serum albumin: Biophysical and in silico studies. J Biomol Struct Dyn 2017; 36:2495-2507. [DOI: 10.1080/07391102.2017.1360207] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Md. Zahirul Kabir
- Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
| | - Hamidah Ghani
- Bioinformatics Programme, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
| | - Saharuddin B. Mohamad
- Bioinformatics Programme, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
- Centre of Research for Computational Sciences and Informatics for Biology, Bioindustry, Environment, Agriculture and Healthcare, University of Malaya, Kuala Lumpur, Malaysia
| | - Zazali Alias
- Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
| | - Saad Tayyab
- Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
- Centre of Research for Computational Sciences and Informatics for Biology, Bioindustry, Environment, Agriculture and Healthcare, University of Malaya, Kuala Lumpur, Malaysia
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26
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Khan AY, Suresh Kumar G. Exploring the binding interaction of potent anticancer drug topotecan with human serum albumin: spectroscopic, calorimetric and fibrillation study. J Biomol Struct Dyn 2017; 36:2463-2473. [DOI: 10.1080/07391102.2017.1359671] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Asma Yasmeen Khan
- Biophysical Chemistry Laboratory, Organic and Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, Kolkata 700 032, India
| | - Gopinatha Suresh Kumar
- Biophysical Chemistry Laboratory, Organic and Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, Kolkata 700 032, India
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27
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Rabbani G, Baig MH, Lee EJ, Cho WK, Ma JY, Choi I. Biophysical Study on the Interaction between Eperisone Hydrochloride and Human Serum Albumin Using Spectroscopic, Calorimetric, and Molecular Docking Analyses. Mol Pharm 2017; 14:1656-1665. [DOI: 10.1021/acs.molpharmaceut.6b01124] [Citation(s) in RCA: 158] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Gulam Rabbani
- Department
of Medical Biotechnology, YeungNam University, 280 Daehak-ro, Gyeongsan, Gyeongbuk-38541, Republic of Korea
| | - Mohammad Hassan Baig
- Department
of Medical Biotechnology, YeungNam University, 280 Daehak-ro, Gyeongsan, Gyeongbuk-38541, Republic of Korea
| | - Eun Ju Lee
- Department
of Medical Biotechnology, YeungNam University, 280 Daehak-ro, Gyeongsan, Gyeongbuk-38541, Republic of Korea
| | - Won-Kyung Cho
- Korean
Medicine (KM) Application Center, Korea Institute of Oriental Medicine (KIOM), Donggu, Daegu-41062, Republic of Korea
| | - Jin Yeul Ma
- Korean
Medicine (KM) Application Center, Korea Institute of Oriental Medicine (KIOM), Donggu, Daegu-41062, Republic of Korea
| | - Inho Choi
- Department
of Medical Biotechnology, YeungNam University, 280 Daehak-ro, Gyeongsan, Gyeongbuk-38541, Republic of Korea
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28
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Rabbani G, Baig MH, Lee EJ, Cho WK, Ma JY, Choi I. Biophysical Study on the Interaction between Eperisone Hydrochloride and Human Serum Albumin Using Spectroscopic, Calorimetric, and Molecular Docking Analyses. Mol Pharm 2017. [DOI: 10.1021/acs.molpharmaceut.6b01124 pmid: 28380300] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Gulam Rabbani
- Department
of Medical Biotechnology, YeungNam University, 280 Daehak-ro, Gyeongsan, Gyeongbuk-38541, Republic of Korea
| | - Mohammad Hassan Baig
- Department
of Medical Biotechnology, YeungNam University, 280 Daehak-ro, Gyeongsan, Gyeongbuk-38541, Republic of Korea
| | - Eun Ju Lee
- Department
of Medical Biotechnology, YeungNam University, 280 Daehak-ro, Gyeongsan, Gyeongbuk-38541, Republic of Korea
| | - Won-Kyung Cho
- Korean
Medicine (KM) Application Center, Korea Institute of Oriental Medicine (KIOM), Donggu, Daegu-41062, Republic of Korea
| | - Jin Yeul Ma
- Korean
Medicine (KM) Application Center, Korea Institute of Oriental Medicine (KIOM), Donggu, Daegu-41062, Republic of Korea
| | - Inho Choi
- Department
of Medical Biotechnology, YeungNam University, 280 Daehak-ro, Gyeongsan, Gyeongbuk-38541, Republic of Korea
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29
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Al-Shabib NA, Khan JM, Ali MS, Al-Lohedan HA, Khan MS, Al-Senaidy AM, Husain FM, Shamsi MB. Exploring the mode of binding between food additive “butylated hydroxytoluene (BHT)” and human serum albumin: Spectroscopic as well as molecular docking study. J Mol Liq 2017. [DOI: 10.1016/j.molliq.2017.01.066] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Sengupta B, Das N, Sen P. Elucidation of μs dynamics of domain-III of human serum albumin during the chemical and thermal unfolding: A fluorescence correlation spectroscopic investigation. Biophys Chem 2017; 221:17-25. [DOI: 10.1016/j.bpc.2016.11.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Revised: 11/09/2016] [Accepted: 11/16/2016] [Indexed: 11/17/2022]
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Affandi ISM, Lee WQ, Feroz SR, Mohamad SB, Tayyab S. Interaction of stattic, a STAT3 inhibitor with human serum albumin: spectroscopic and computational study. J Biomol Struct Dyn 2016; 35:3581-3590. [DOI: 10.1080/07391102.2016.1264887] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Ida Syazwani M. Affandi
- Faculty of Science, Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, University of Malaya, Kuala Lumpur, Malaysia
| | - Wei Qi Lee
- Faculty of Science, Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, University of Malaya, Kuala Lumpur, Malaysia
| | - Shevin R. Feroz
- Faculty of Science, Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, University of Malaya, Kuala Lumpur, Malaysia
| | - Saharuddin B. Mohamad
- Faculty of Science, Bioinformatics Programme, Institute of Biological Sciences, University of Malaya, Kuala Lumpur, Malaysia
- Centre of Research for Computational Sciences and Informatics for Biology, Bioindustry, Environment, Agriculture and Healthcare (CRYSTAL), University of Malaya, Kuala Lumpur, Malaysia
| | - Saad Tayyab
- Faculty of Science, Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, University of Malaya, Kuala Lumpur, Malaysia
- Centre of Research for Computational Sciences and Informatics for Biology, Bioindustry, Environment, Agriculture and Healthcare (CRYSTAL), University of Malaya, Kuala Lumpur, Malaysia
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Maksimov EG, Moldenhauer M, Shirshin EA, Parshina EA, Sluchanko NN, Klementiev KE, Tsoraev GV, Tavraz NN, Willoweit M, Schmitt FJ, Breitenbach J, Sandmann G, Paschenko VZ, Friedrich T, Rubin AB. A comparative study of three signaling forms of the orange carotenoid protein. PHOTOSYNTHESIS RESEARCH 2016; 130:389-401. [PMID: 27161566 DOI: 10.1007/s11120-016-0272-8] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 04/27/2016] [Indexed: 06/05/2023]
Abstract
Orange carotenoid protein (OCP) is a water-soluble photoactive protein responsible for a photoprotective mechanism of nonphotochemical quenching in cyanobacteria. Under blue-green illumination, OCP converts from the stable orange into the signaling red quenching form; however, the latter form could also be obtained by chemical activation with high concentrations of sodium thiocyanate (NaSCN) or point mutations. In this work, we show that a single replacement of tryptophan-288, normally involved in protein-chromophore interactions, by alanine, results in formation of a new protein form, hereinafter referred to as purple carotenoid protein (PCP). Comparison of resonance Raman spectra of the native photoactivated red form, chemically activated OCP, and PCP reveals that carotenoid conformation is sensitive to the structure of the C-domain, implicating that the chromophore retains some interactions with this part of the protein in the active red form. Combination of differential scanning fluorimetry and picosecond time-resolved fluorescence anisotropy measurements allowed us to compare the stability of different OCP forms and to estimate relative differences in protein rotation rates. These results were corroborated by hydrodynamic analysis of proteins by dynamic light scattering and analytical size-exclusion chromatography, indicating that the light-induced conversion of the protein is accompanied by a significant increase in its size. On the whole, our data support the idea that the red form of OCP is a molten globule-like protein in which, however, interactions between the carotenoid and the C-terminal domain are preserved.
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Affiliation(s)
- E G Maksimov
- Department of Biophysics, Faculty of Biology, M.V. Lomonosov Moscow State University, 119992, Moscow, Russia.
| | - M Moldenhauer
- Institute of Chemistry PC 14, Technical University of Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - E A Shirshin
- Department of Quantum Electronics, Faculty of Physics, M.V. Lomonosov Moscow State University, 119992, Moscow, Russia
| | - E A Parshina
- Department of Biophysics, Faculty of Biology, M.V. Lomonosov Moscow State University, 119992, Moscow, Russia
| | - N N Sluchanko
- A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, 119071, Moscow, Russia
| | - K E Klementiev
- Department of Biophysics, Faculty of Biology, M.V. Lomonosov Moscow State University, 119992, Moscow, Russia
| | - G V Tsoraev
- Department of Biophysics, Faculty of Biology, M.V. Lomonosov Moscow State University, 119992, Moscow, Russia
| | - N N Tavraz
- Institute of Chemistry PC 14, Technical University of Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - M Willoweit
- Institute of Chemistry PC 14, Technical University of Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - F-J Schmitt
- Institute of Chemistry PC 14, Technical University of Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - J Breitenbach
- Institute for Molecular Biosciences, Johann Wolfgang Goethe University of Frankfurt, Max-von-Laue-Straße 9, 60438, Frankfurt, Germany
| | - G Sandmann
- Institute for Molecular Biosciences, Johann Wolfgang Goethe University of Frankfurt, Max-von-Laue-Straße 9, 60438, Frankfurt, Germany
| | - V Z Paschenko
- Department of Biophysics, Faculty of Biology, M.V. Lomonosov Moscow State University, 119992, Moscow, Russia
| | - T Friedrich
- Institute of Chemistry PC 14, Technical University of Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - A B Rubin
- Department of Biophysics, Faculty of Biology, M.V. Lomonosov Moscow State University, 119992, Moscow, Russia
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Stirpe A, Pantusa M, Rizzuti B, De Santo MP, Sportelli L, Bartucci R, Guzzi R. Resveratrol induces thermal stabilization of human serum albumin and modulates the early aggregation stage. Int J Biol Macromol 2016; 92:1049-1056. [DOI: 10.1016/j.ijbiomac.2016.08.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 08/03/2016] [Accepted: 08/06/2016] [Indexed: 10/21/2022]
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Lee WQ, Affandi ISM, Feroz SR, Mohamad SB, Tayyab S. Evaluation of pendimethalin binding to human serum albumin: Insights from spectroscopic and molecular modeling approach. J Biochem Mol Toxicol 2016; 31. [DOI: 10.1002/jbt.21839] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2016] [Revised: 08/25/2016] [Accepted: 08/28/2016] [Indexed: 12/23/2022]
Affiliation(s)
- Wei Qi Lee
- Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, Faculty of Science; University of Malaya; 50603 Kuala Lumpur Malaysia
| | - Ida Syazwani M. Affandi
- Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, Faculty of Science; University of Malaya; 50603 Kuala Lumpur Malaysia
| | - Shevin R. Feroz
- Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, Faculty of Science; University of Malaya; 50603 Kuala Lumpur Malaysia
| | - Saharuddin B. Mohamad
- Bioinformatics Programme, Institute of Biological Sciences, Faculty of Science; University of Malaya; 50603 Kuala Lumpur Malaysia
- Centre of Research for Computational Sciences and Informatics for Biology, Bioindustry, Environment, Agriculture and Healthcare (CRYSTAL); University of Malaya; 50603 Kuala Lumpur Malaysia
| | - Saad Tayyab
- Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, Faculty of Science; University of Malaya; 50603 Kuala Lumpur Malaysia
- Centre of Research for Computational Sciences and Informatics for Biology, Bioindustry, Environment, Agriculture and Healthcare (CRYSTAL); University of Malaya; 50603 Kuala Lumpur Malaysia
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Nikolaidis A, Moschakis T. Studying the denaturation of bovine serum albumin by a novel approach of difference-UV analysis. Food Chem 2016; 215:235-44. [PMID: 27542472 DOI: 10.1016/j.foodchem.2016.07.133] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 07/14/2016] [Accepted: 07/23/2016] [Indexed: 10/21/2022]
Abstract
A novel approach in the analysis of difference-UV spectrophotometric data for determining the heat denaturation degree of bovine serum albumin (BSA) was assessed. Five different parameters of difference-UV spectra were obtained by subtracting spectra of unheated and denatured protein solutions at different temperature-time combinations. BSA was found to exhibit a maximum degree of heat denaturation of about 17% compared to the complete unfolding caused by 6M guanidine hydrochloride. This low degree of heat denaturation is probably caused by the aggregation of the initially unfolded protein molecules. The kinetic analysis exhibited discontinuities in the Arrhenius plots, distinguishing the unfolding and aggregation phases of the denaturation process, whereas such a discrimination could not be obtained by differential scanning calorimetry analyses. The proposed method is accurate, fast, simple and sensitive enough to detect changes in the protein heat denaturation even at short temperature-time intervals.
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Affiliation(s)
- Athanasios Nikolaidis
- Department of Food Science and Technology, School of Agriculture, Aristotle University, GR-541 24 Thessaloniki, Greece
| | - Thomas Moschakis
- Department of Food Science and Technology, School of Agriculture, Aristotle University, GR-541 24 Thessaloniki, Greece.
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Chibber S, Ahmad I. Molecular docking, a tool to determine interaction of CuO and TiO 2 nanoparticles with human serum albumin. Biochem Biophys Rep 2016; 6:63-67. [PMID: 28955863 PMCID: PMC5600462 DOI: 10.1016/j.bbrep.2016.03.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 03/03/2016] [Accepted: 03/10/2016] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND We study the human serum albumin (HSA) protein-CuO nanoparticle interaction to identify the specific binding site of protein with CuO nanoparticles by molecular docking and compared it with HSA-TiO2 nanoparticle interaction. METHODS The protein structural data that was obtained using Autodock 4.2. RESULTS In case of CuO np-HSA interaction, the distances from the centre of Subdomain IIIA to Arg-472 is 2.113 Å and Lys 475, Glu 492, Ala 490, Cys 487, Ala 490 are the bound neighbouring residues with Lys 475, Glu 492 at aliphatic region. The binding energy generated was -1.64 kcal mol-1. However, for TiO2 nanoparticle, the binding region is surrounded by Arg 257, Ala 258, Ser 287, His 288, Leu 283, Ala 254, Tyr 150 (subdomain II A) as neighbouring residue. Moreover, Glu 285, Lys 286 forms aliphatic grove for TiO2-HSA, Ser-287 at the centre region form hydrogen bond with nanoparticle and Leu 283, Leu 284 forming hydrophopobic grove for TiO2 nanoparticle-HSA interaction. The binding energy generated was -2.47 kcal mol-1. CONCLUSIONS Analysis suggests that CuO bind to suldow site II i.e subdomain III A of HSA protein where as TiO2 nanoparticle bind to suldow site I i.e subdomain IIA of HSA protein. GENERAL SIGNIFICANCE The structural information that derives from this study for CuO and TiO2 nanoparticles may be useful in terms of both high and low-affinity binding sites when designing these nanoparticles based drugs delivery system.
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Affiliation(s)
- Sandesh Chibber
- Institute of Life Sciences, School of Science and Technology, Ahmedabad University, Ahmedabad 380009, India
| | - Irshad Ahmad
- Department of Biochemistry, F/O Life Sciences, Aligarh Muslim University, Aligarh 202002, India
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Hsieh SR, Reddy PM, Chang CJ, Kumar A, Wu WC, Lin HY. Exploring the Behavior of Bovine Serum Albumin in Response to Changes in the Chemical Composition of Responsive Polymers: Experimental and Simulation Studies. Polymers (Basel) 2016; 8:E238. [PMID: 30979331 PMCID: PMC6432219 DOI: 10.3390/polym8060238] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 06/13/2016] [Accepted: 06/13/2016] [Indexed: 01/06/2023] Open
Abstract
Knowledge of the interactions between polymer and protein is very important to fabricate the potential materials for many bio-related applications. In this regard, the present work investigated the effect of copolymers on the conformation and thermal stability of bovine serum albumin (BSA) with the aid of biophysical techniques such as fluorescence spectroscopy, circular dichroism (CD) spectroscopy and differential scanning calorimetry (DSC). In comparison with that of copolymer PGA-1.5, our fluorescence spectroscopy results reveal that the copolymer PGA-1, which has a lower PEGMA/AA ratio, shows greater influence on the conformation of BSA. Copolymers induced unfolding of the polypeptide chain of BSA, which was confirmed from the loss in the negative ellipticity of CD spectra. DSC results showed that the addition of PGA-1 and PGA-1.5 (0.05% (w/v) decreased the transition temperature by 14.8 and 11.5 °C, respectively). The results from the present study on the behavior of protein in response to changes in the chemical composition of synthetic polymers are significant for various biological applications such as enzyme immobilization, protein separations, sensor development and stimuli-responsive systems.
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Affiliation(s)
- Shih-Rong Hsieh
- Department of Surgery, Taichung Veterans General Hospital, 1650 Taiwan Boulevard Section 4, Taichung 40705, Taiwan.
| | - P Madhusudhana Reddy
- Department of Chemical Engineering, Feng Chia University, 100, Wenhwa Road, Seatwen, Taichung 40724, Taiwan.
| | - Chi-Jung Chang
- Department of Chemical Engineering, Feng Chia University, 100, Wenhwa Road, Seatwen, Taichung 40724, Taiwan.
| | - Awanish Kumar
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
| | - Wan-Chi Wu
- Department of Chemical Engineering, Feng Chia University, 100, Wenhwa Road, Seatwen, Taichung 40724, Taiwan.
| | - Hui-Yi Lin
- School of Pharmacy, China Medical University, 91, Hsueh-Shih Road, Taichung 40402, Taiwan.
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38
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Biswas S, Chowdhury PK. Correlated and Anticorrelated Domain Movement of Human Serum Albumin: A Peek into the Complexity of the Crowded Milieu. J Phys Chem B 2016; 120:4897-911. [DOI: 10.1021/acs.jpcb.6b01671] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Saikat Biswas
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Pramit Kumar Chowdhury
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
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39
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Nagy M, Rácz D, Kovács SL, Lázár L, Fehér PP, Purgel M, Zsuga M, Kéki S. New blue light-emitting isocyanobiphenyl based fluorophores: Their solvatochromic and biolabeling properties. J Photochem Photobiol A Chem 2016. [DOI: 10.1016/j.jphotochem.2015.12.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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40
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Jahanshahi-Anbuhi S, Kannan B, Leung V, Pennings K, Liu M, Carrasquilla C, White D, Li Y, Pelton RH, Brennan JD, Filipe CDM. Simple and ultrastable all-inclusive pullulan tablets for challenging bioassays. Chem Sci 2016; 7:2342-2346. [PMID: 29997777 PMCID: PMC6003609 DOI: 10.1039/c5sc04184h] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 01/01/2016] [Indexed: 01/25/2023] Open
Abstract
Many biodetection systems employ labile enzymes and substrates that need special care, making it hard to routinely use them for point-of-care or field applications. In this work we provide a simple solution to this challenging problem through the creation of all-inclusive pullulan assay tablets. The proposed tablet system not only enhances the long-term stability of both enzymes and organic substrates, but also simplifies the assay procedure. The enhanced stability is attributed to two factors: the restriction of the molecular motion of proteins and impermeability to molecular oxygen afforded by the tables. These tablets dissolve rapidly upon addition to testing samples, making the test very easy to perform. Using the ATP-detecting luciferase-luciferin system as an example, we show that the tablet-based assay can achieve highly sensitive detection of ATP in biological samples and that the activity of the assay tablets remains unchanged for over a month at room temperature.
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Affiliation(s)
- Sana Jahanshahi-Anbuhi
- Biointerfaces Institute , McMaster University , 1280 Main St W , Hamilton , ON L8S 4L8 , Canada . ; http://www.biointerfaces.ca ; Tel: +1-905-525-9140 ext. 20682
- Department of Chemical Engineering , McMaster University , 1280 Main St W , Hamilton , ON L8S 4L7 , Canada . ; Tel: +1-905-525-9140 ext. 27278
| | - Balamurali Kannan
- Biointerfaces Institute , McMaster University , 1280 Main St W , Hamilton , ON L8S 4L8 , Canada . ; http://www.biointerfaces.ca ; Tel: +1-905-525-9140 ext. 20682
| | - Vincent Leung
- Department of Chemical Engineering , McMaster University , 1280 Main St W , Hamilton , ON L8S 4L7 , Canada . ; Tel: +1-905-525-9140 ext. 27278
| | - Kevin Pennings
- Department of Chemical Engineering , McMaster University , 1280 Main St W , Hamilton , ON L8S 4L7 , Canada . ; Tel: +1-905-525-9140 ext. 27278
| | - Meng Liu
- Biointerfaces Institute , McMaster University , 1280 Main St W , Hamilton , ON L8S 4L8 , Canada . ; http://www.biointerfaces.ca ; Tel: +1-905-525-9140 ext. 20682
- Department of Biochemistry & Biomedical Sciences , McMaster University , 1280 Main St W , Hamilton , ON L8S 3Z5 , Canada
| | - Carmen Carrasquilla
- Biointerfaces Institute , McMaster University , 1280 Main St W , Hamilton , ON L8S 4L8 , Canada . ; http://www.biointerfaces.ca ; Tel: +1-905-525-9140 ext. 20682
| | - Dawn White
- Biointerfaces Institute , McMaster University , 1280 Main St W , Hamilton , ON L8S 4L8 , Canada . ; http://www.biointerfaces.ca ; Tel: +1-905-525-9140 ext. 20682
| | - Yingfu Li
- Biointerfaces Institute , McMaster University , 1280 Main St W , Hamilton , ON L8S 4L8 , Canada . ; http://www.biointerfaces.ca ; Tel: +1-905-525-9140 ext. 20682
- Department of Biochemistry & Biomedical Sciences , McMaster University , 1280 Main St W , Hamilton , ON L8S 3Z5 , Canada
| | - Robert H Pelton
- Biointerfaces Institute , McMaster University , 1280 Main St W , Hamilton , ON L8S 4L8 , Canada . ; http://www.biointerfaces.ca ; Tel: +1-905-525-9140 ext. 20682
- Department of Chemical Engineering , McMaster University , 1280 Main St W , Hamilton , ON L8S 4L7 , Canada . ; Tel: +1-905-525-9140 ext. 27278
| | - John D Brennan
- Biointerfaces Institute , McMaster University , 1280 Main St W , Hamilton , ON L8S 4L8 , Canada . ; http://www.biointerfaces.ca ; Tel: +1-905-525-9140 ext. 20682
| | - Carlos D M Filipe
- Biointerfaces Institute , McMaster University , 1280 Main St W , Hamilton , ON L8S 4L8 , Canada . ; http://www.biointerfaces.ca ; Tel: +1-905-525-9140 ext. 20682
- Department of Chemical Engineering , McMaster University , 1280 Main St W , Hamilton , ON L8S 4L7 , Canada . ; Tel: +1-905-525-9140 ext. 27278
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Yadav R, Sengupta B, Sen P. Effect of sucrose on chemically and thermally induced unfolding of domain-I of human serum albumin: Solvation dynamics and fluorescence anisotropy study. Biophys Chem 2016; 211:59-69. [PMID: 26930029 DOI: 10.1016/j.bpc.2016.02.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 02/16/2016] [Accepted: 02/17/2016] [Indexed: 12/12/2022]
Abstract
The present study is devoted to understand the effect of sucrose on the hydration dynamics and rotational relaxation dynamics within the domain-I of HSA during chemically as well as thermally induced unfolding. It has been observed that the average solvation time become slower in the presence of sucrose for the lower concentrations of GnHCl, however at higher concentrations of GnHCl the effect of sucrose is almost negligible. From the time resolved fluorescence anisotropy it has been observed that in the lower concentration region of GnHCl the sucrose induced stabilization is small as compared to the higher concentrations of GnHCl. We have concluded that the hydration dynamics plays an important role in the sucrose induced stabilization process at the low concentration region; whereas environmental restriction is responsible at the higher concentration of GnHCl. However, we have observed a negligible stabilizing effect of sucrose towards the temperature induced unfolding.
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Affiliation(s)
- Rajeev Yadav
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208 016, UP, India
| | - Bhaswati Sengupta
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208 016, UP, India
| | - Pratik Sen
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, 208 016, UP, India.
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Samanta N, Luong TQ, Das Mahanta D, Mitra RK, Havenith M. Effect of Short Chain Poly(ethylene glycol)s on the Hydration Structure and Dynamics around Human Serum Albumin. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:831-837. [PMID: 26720549 DOI: 10.1021/acs.langmuir.5b03884] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We report the changes in the hydration dynamics around a globular protein, human serum albumin (HSA), in the presence of two short chain crowding agents, namely poly(ethylene glycol)s (PEG 200 and 400). The change in the network water structure is investigated using FTIR spectroscopy in the far-infrared (FIR) frequency range. Site specific changes are obtained by time-resolved fluorescence spectroscopic technique using the intrinsic fluorophore tryptophan (Trp214) of HSA. The collective hydration dynamics of HSA in the presence of PEG molecules are obtained using terahertz (THz) time domain spectroscopy (TTDS) and high intensity p-Ge THz measurements. Our study affirms a considerable perturbation of HSA hydration beyond a critical concentration of PEG.
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Affiliation(s)
- Nirnay Samanta
- Department of Chemical, Biological and Macromolecular Sciences, S.N. Bose National Centre for Basic Sciences , Block JD, Sector III, Salt Lake, Kolkata 700098, India
| | - Trung Quan Luong
- Department of Physical Chemistry II, Ruhr-University Bochum , 44780 Bochum, Germany
| | - Debasish Das Mahanta
- Department of Chemical, Biological and Macromolecular Sciences, S.N. Bose National Centre for Basic Sciences , Block JD, Sector III, Salt Lake, Kolkata 700098, India
| | - Rajib Kumar Mitra
- Department of Chemical, Biological and Macromolecular Sciences, S.N. Bose National Centre for Basic Sciences , Block JD, Sector III, Salt Lake, Kolkata 700098, India
| | - Martina Havenith
- Department of Physical Chemistry II, Ruhr-University Bochum , 44780 Bochum, Germany
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Arya S, Kumari A, Dalal V, Bhattacharya M, Mukhopadhyay S. Appearance of annular ring-like intermediates during amyloid fibril formation from human serum albumin. Phys Chem Chem Phys 2015; 17:22862-71. [PMID: 26264974 DOI: 10.1039/c5cp03782d] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The self-assembly of proteins triggered by a conformational switch into highly ordered β-sheet rich amyloid fibrils has captivated burgeoning interest in recent years due to the involvement of amyloids in a variety of human diseases and a diverse range of biological functions. Here, we have investigated the mechanism of fibrillogenesis of human serum albumin (HSA), an all-α-helical protein, using an array of biophysical tools that include steady-state as well as time-resolved fluorescence, circular dichroism and Raman spectroscopy in conjunction with atomic force microscopy (AFM). Investigations into the temporal evolution of nanoscale morphology using AFM revealed the presence of ring-like intermediates that subsequently transformed into worm-like fibrils presumably by a ring-opening mechanism. Additionally, a multitude of morphologically-diverse oligomers were observed on the pathway to amyloid formation. Kinetic analysis using multiple structural probes in-tandem indicated that HSA amyloid assembly is a concerted process encompassing a major structural change that is primarily mediated by hydrophobic interactions between thermally-induced disordered segments originating in various domains. A slower growth kinetics of aggregates suggested that the protein structural reorganization is a prerequisite for fibril formation. Moreover, time-dependent Raman spectroscopic studies of HSA aggregation provided key molecular insights into the conformational transitions occurring within the protein amide backbone and at the residue-specific level. Our data revealed the emergence of conformationally-diverse disulfides as a consequence of structural reorganization and sequestration of tyrosines into the hydrophobic amyloid core comprising antiparallel cross β-sheets.
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Affiliation(s)
- Shruti Arya
- Centre for Protein Science Design and Engineering, Indian Institute of Science Education and Research (IISER), Mohali 140306, Punjab, India.
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Groza RC, Li B, Ryder AG. Anisotropy resolved multidimensional emission spectroscopy (ARMES): A new tool for protein analysis. Anal Chim Acta 2015; 886:133-42. [PMID: 26320645 DOI: 10.1016/j.aca.2015.06.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 06/02/2015] [Accepted: 06/04/2015] [Indexed: 01/23/2023]
Abstract
Structural analysis of proteins using the emission of intrinsic fluorophores is complicated by spectral overlap. Anisotropy resolved multidimensional emission spectroscopy (ARMES) overcame the overlap problem by the use of anisotropy, with chemometric analysis, to better resolve emission from different fluorophores. Total synchronous fluorescence scan (TSFS) provided information about all the fluorophores that contributed to emission while anisotropy provided information about the environment of each fluorophore. Here the utility of ARMES was demonstrated via study of the chemical and thermal denaturation of human serum albumin (HSA). Multivariate curve resolution (MCR) analysis of the constituent polarized emission ARMES data resolved contributions from four emitters: fluorescence from tryptophan (Trp), solvent exposed tyrosine (Tyr), Tyr in a hydrophobic environment, and room temperature phosphorescence (RTP) from Trp. The MCR scores, anisotropy, and literature validated these assignments and showed all the expected transitions during HSA unfolding. This new methodology for comprehensive intrinsic fluorescence analysis of proteins is applicable to any protein containing multiple fluorophores.
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Affiliation(s)
- Radu Constantin Groza
- Nanoscale Biophotonics Laboratory, School of Chemistry, National University of Ireland, Galway, Galway, Ireland
| | - Boyan Li
- Nanoscale Biophotonics Laboratory, School of Chemistry, National University of Ireland, Galway, Galway, Ireland
| | - Alan G Ryder
- Nanoscale Biophotonics Laboratory, School of Chemistry, National University of Ireland, Galway, Galway, Ireland.
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The Minor Capsid Protein VP11 of Thermophilic Bacteriophage P23-77 Facilitates Virus Assembly by Using Lipid-Protein Interactions. J Virol 2015; 89:7593-603. [PMID: 25972558 DOI: 10.1128/jvi.00262-15] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 05/05/2015] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Thermus thermophilus bacteriophage P23-77 is the type member of a new virus family of icosahedral, tailless, inner-membrane-containing double-stranded DNA (dsDNA) viruses infecting thermophilic bacteria and halophilic archaea. The viruses have a unique capsid architecture consisting of two major capsid proteins assembled in various building blocks. We analyzed the function of the minor capsid protein VP11, which is the third known capsid component in bacteriophage P23-77. Our findings show that VP11 is a dynamically elongated dimer with a predominantly α-helical secondary structure and high thermal stability. The high proportion of basic amino acids in the protein enables electrostatic interaction with negatively charged molecules, including nucleic acid and large unilamellar lipid vesicles (LUVs). The plausible biological function of VP11 is elucidated by demonstrating the interactions of VP11 with Thermus-derived LUVs and with the major capsid proteins by means of the dynamic-light-scattering technique. In particular, the major capsid protein VP17 was able to link VP11-complexed LUVs into larger particles, whereas the other P23-77 major capsid protein, VP16, was unable to link VP11-comlexed LUVs. Our results rule out a previously suggested penton function for VP11. Instead, the electrostatic membrane association of VP11 triggers the binding of the major capsid protein VP17, thus facilitating a controlled incorporation of the two different major protein species into the assembling capsid. IMPORTANCE The study of thermophilic viruses with inner membranes provides valuable insights into the mechanisms used for stabilization and assembly of protein-lipid systems at high temperatures. Our results reveal a novel way by which an internal membrane and outer capsid shell are linked in a virus that uses two different major protein species for capsid assembly. We show that a positive protein charge is important in order to form electrostatic interactions with the lipid surface, thereby facilitating the incorporation of other capsid proteins on the membrane surface. This implies an alternative function for basic proteins present in the virions of other lipid-containing thermophilic viruses, whose proposed role in genome packaging is based on their capability to bind DNA. The unique minor capsid protein of bacteriophage P23-77 resembles in its characteristics the scaffolding proteins of tailed phages, though it constitutes a substantial part of the mature virion.
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Low molecular weight silicones particularly facilitate human serum albumin denaturation. Colloids Surf B Biointerfaces 2015; 128:586-593. [DOI: 10.1016/j.colsurfb.2015.03.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 02/23/2015] [Accepted: 03/02/2015] [Indexed: 11/19/2022]
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Biswas S, Chowdhury PK. Unusual domain movement in a multidomain protein in the presence of macromolecular crowders. Phys Chem Chem Phys 2015; 17:19820-33. [DOI: 10.1039/c5cp02674a] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
FRET-based distance changes between domains I and II of HSA reveal significant differences in the manner in which dextran based macromolecular crowding agents influence the serum protein.
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Affiliation(s)
- Saikat Biswas
- Department of Chemistry
- Indian Institute of Technology Delhi
- New Delhi 110016
- India
| | - Pramit K. Chowdhury
- Department of Chemistry
- Indian Institute of Technology Delhi
- New Delhi 110016
- India
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Yaseen Z, Rehman SU, Tabish M, Shalla AH, Kabir-ud-Din KUD. Modulation of bovine serum albumin fibrillation by ester bonded and conventional gemini surfactants. RSC Adv 2015. [DOI: 10.1039/c5ra08923a] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Modulation of bovine serum albumin fibrillation by gemini surfactants.
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Affiliation(s)
- Zahid Yaseen
- Department of Chemistry
- Islamic University of Science and Technology
- Pulwama 192122
- India
| | - Sayeed Ur Rehman
- Department of Biochemistry
- Faculty of Life Sciences
- Aligarh Muslim University
- Aligarh-202002
- India
| | - Mohammad Tabish
- Department of Biochemistry
- Faculty of Life Sciences
- Aligarh Muslim University
- Aligarh-202002
- India
| | - Aabid H. Shalla
- Department of Chemistry
- Islamic University of Science and Technology
- Pulwama 192122
- India
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Gupta BS, Taha M, Lee MJ. Buffers more than buffering agent: introducing a new class of stabilizers for the protein BSA. Phys Chem Chem Phys 2015; 17:1114-33. [DOI: 10.1039/c4cp04663c] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this study, we have analyzed the influence of four biological buffers on the thermal stability of bovine serum albumin (BSA) using dynamic light scattering (DLS).
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Affiliation(s)
- Bhupender S. Gupta
- Department of Chemical Engineering
- National Taiwan University of Science and Technology
- Taipei 106-07
- Taiwan
| | - Mohamed Taha
- CICECO
- Departamento de Química
- Universidade de Aveiro
- Portugal
| | - Ming-Jer Lee
- Department of Chemical Engineering
- National Taiwan University of Science and Technology
- Taipei 106-07
- Taiwan
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Concomitant Raman spectroscopy and dynamic light scattering for characterization of therapeutic proteins at high concentrations. Anal Biochem 2014; 472:7-20. [PMID: 25475399 DOI: 10.1016/j.ab.2014.11.016] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 11/19/2014] [Accepted: 11/20/2014] [Indexed: 11/21/2022]
Abstract
A Raman spectrometer and dynamic light scattering system were combined in a single platform (Raman-DLS) to provide concomitant higher order structural and hydrodynamic size data for therapeutic proteins at high concentration. As model therapeutic proteins, we studied human serum albumin (HSA) and intravenous immunoglobulin (IVIG). HSA concentration and temperature interval during heating did not affect the onset temperatures for conformation perturbation or aggregation. The impact of pH on thermal stability of HSA was tested at pHs 3, 5, and 8. Stability was the greatest at pH 8, but distinct unfolding and aggregation behaviors were observed at the different pHs. HSA structural transitions and aggregation kinetics were also studied in real time during isothermal incubations at pH 7. In a forced oxidation study, it was found that hydrogen peroxide (H2O2) treatment reduced the thermal stability of HSA. Finally, the structure and thermal stability of IVIG were studied, and a comprehensive characterization of heating-induced structural perturbations and aggregation was obtained. In conclusion, by providing comprehensive data on protein tertiary and secondary structures and hydrodynamic size during real-time heating or isothermal incubation experiments, the Raman-DLS system offers unique physical insights into the properties of high-concentration protein samples.
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