1
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Scognamiglio PL, Vicidomini C, Fontanella F, De Stefano C, Palumbo R, Roviello GN. Protein Binding of Benzofuran Derivatives: A CD Spectroscopic and In Silico Comparative Study of the Effects of 4-Nitrophenyl Functionalized Benzofurans and Benzodifurans on BSA Protein Structure. Biomolecules 2022; 12:biom12020262. [PMID: 35204762 PMCID: PMC8961527 DOI: 10.3390/biom12020262] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 01/31/2022] [Accepted: 02/01/2022] [Indexed: 02/06/2023] Open
Abstract
Benzofuran derivatives are synthetic compounds that are finding an increasing interest in the scientific community not only as building blocks for the realization of new materials, but also as potential drugs thanks to their ability to interact with nucleic acids, interfere with the amyloid peptide aggregation and cancer cell cycle. However, their ability to interact with proteins is a theme still in need of investigation for the therapeutic importance that benzofurans could have in the modulation of protein-driven processes and for the possibility of making use of serum albumins as benzofurans delivery systems. To this scope, we investigated the protein binding ability of two 4-nitrophenyl-functionalized benzofurans previously synthesized in our laboratory and herein indicated as BF1 and BDF1, which differed for the number of furan rings (a single moiety in BF1, two in BDF1), using bovine serum albumin (BSA) as a model protein. By circular dichroism (CD) spectroscopy we demonstrated the ability of the two heteroaromatic compounds to alter the secondary structure of the serum albumin leading to different consequences in terms of BSA thermal stability with respect to the unbound protein (ΔTm > 3 °C for BF1, −0.8 °C for BDF1 with respect to unbound BSA, in PBS buffer, pH 7.5) as revealed in our CD melting studies. Moreover, a molecular docking study allowed us to compare the possible ligand binding modes of the mono and difuranic derivatives showing that while BF1 is preferentially housed in the interior of protein structure, BDF1 is predicted to bind the albumin surface with a lower affinity than BF1. Interestingly, the different affinity for the protein target predicted computationally was confirmed also experimentally by fluorescence spectroscopy (kD = 142.4 ± 64.6 nM for BDF1 vs. 28.4 ± 10.1 nM for BF1). Overall, the above findings suggest the ability of benzofurans to bind serum albumins that could act as their carriers in drug delivery applications.
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Affiliation(s)
| | - Caterina Vicidomini
- Istituto di Biostrutture e Bioimmagini IBB-CNR, via Tommaso De Amicis 95, I-80145 Naples, Italy; (C.V.); (R.P.)
| | - Francesco Fontanella
- Department of Electrical and Information Engineering (DIEI), University of Cassino and Southern Lazio, 03043 Cassino (FR), Italy; (F.F.); (C.D.S.)
| | - Claudio De Stefano
- Department of Electrical and Information Engineering (DIEI), University of Cassino and Southern Lazio, 03043 Cassino (FR), Italy; (F.F.); (C.D.S.)
| | - Rosanna Palumbo
- Istituto di Biostrutture e Bioimmagini IBB-CNR, via Tommaso De Amicis 95, I-80145 Naples, Italy; (C.V.); (R.P.)
| | - Giovanni N. Roviello
- Istituto di Biostrutture e Bioimmagini IBB-CNR, via Tommaso De Amicis 95, I-80145 Naples, Italy; (C.V.); (R.P.)
- Correspondence: ; Tel.: +39-3491928417
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2
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Lin J, Guo X, Ai C, Zhang T, Yu S. Genipin crosslinked sugar beet pectin-whey protein isolate/bovine serum albumin conjugates with enhanced emulsifying properties. Food Hydrocoll 2020. [DOI: 10.1016/j.foodhyd.2020.105802] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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3
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Effect of pH and protein particle shape on the stability of amylopectin–xyloglucan water-in-water emulsions. Food Hydrocoll 2020. [DOI: 10.1016/j.foodhyd.2020.105769] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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4
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Raman SC, Mejías-Pérez E, Gomez CE, García-Arriaza J, Perdiguero B, Vijayan A, Pérez-Ruiz M, Cuervo A, Santiago C, Sorzano COS, Sánchez-Corzo C, Moog C, Burger JA, Schorcht A, Sanders RW, Carrascosa JL, Esteban M. The Envelope-Based Fusion Antigen GP120C14K Forming Hexamer-Like Structures Triggers T Cell and Neutralizing Antibody Responses Against HIV-1. Front Immunol 2019; 10:2793. [PMID: 31867001 PMCID: PMC6904342 DOI: 10.3389/fimmu.2019.02793] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 11/14/2019] [Indexed: 11/20/2022] Open
Abstract
There is an urgent need for the development of potent vaccination regimens that are able to induce specific T and B cell responses against human immunodeficiency virus type 1 (HIV-1). Here, we describe the generation and characterization of a fusion antigen comprised of the HIV-1 envelope GP120 glycoprotein from clade C (GP120C) fused at its C-terminus, with the modified vaccinia virus (VACV) 14K protein (A27L gene) (termed GP120C14K). The design is directed toward improving the immunogenicity of the GP120C protein through its oligomerization facilitated by the fused VACV 14K protein that results in hexamer-like structures. Two different immunogens were generated: a recombinant GP120C14K fusion protein (purified from a stable CHO-K1 cell line) and a recombinant modified vaccinia virus Ankara (MVA) poxvirus vector expressing the GP120C14K fusion protein (termed MVA-GP120C14K). The GP120C14K fusion protein is recognized by broadly neutralizing antibodies (bNAbs) against HIV-1. In a murine model, a heterologous prime/boost immunization regimen with MVA-GP120C14K prime followed by adjuvanted GP120C14K protein boost generated stronger and polyfunctional HIV-1 Env-specific CD8 T cell responses when compared with the delivery of the monomeric GP120C form. Furthermore, the immunization protocol MVA-GP120C14K/GP120C14K elicited higher HIV-1 Env-specific T follicular helper cells, germinal center B cells and antibody responses than monomeric GP120. In addition, a similar MVA-GP120C14K prime/GP120C14K protein boost regimen performed in rabbits triggered high HIV-1-Env-specific IgG binding antibody titers that were capable of neutralizing HIV-1 pseudoviruses. The extent of HIV-1 neutralization was comparable to that elicited by the current standard GP140 SOSIP trimers from clades B and C when immunized as MVA-SOSIP prime/SOSIP protein boost regimen. Overall, the novel fusion antigen and the corresponding immunization scheme provided in this report can therefore be considered as potential vaccine strategies against HIV-1.
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Affiliation(s)
- Suresh C Raman
- Department of Molecular and Cellular Biology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Madrid, Spain
| | - Ernesto Mejías-Pérez
- Department of Molecular and Cellular Biology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Madrid, Spain
| | - Carmen E Gomez
- Department of Molecular and Cellular Biology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Madrid, Spain
| | - Juan García-Arriaza
- Department of Molecular and Cellular Biology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Madrid, Spain
| | - Beatriz Perdiguero
- Department of Molecular and Cellular Biology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Madrid, Spain
| | - Aneesh Vijayan
- Department of Molecular and Cellular Biology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Madrid, Spain
| | - Mar Pérez-Ruiz
- Department of Structure of Macromolecules, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Madrid, Spain
| | - Ana Cuervo
- Department of Structure of Macromolecules, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Madrid, Spain
| | - César Santiago
- X-ray Crystallization Unit, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Madrid, Spain
| | - Carlos Oscar S Sorzano
- Biocomputing Unit, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Madrid, Spain
| | - Cristina Sánchez-Corzo
- Department of Molecular and Cellular Biology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Madrid, Spain
| | - Christiane Moog
- INSERM U1109, Fédération Hospitalo-Universitaire (FHU) OMICARE, Fédération de Médecine Translationnelle de Strasbourg (FMTS), Université de Strasbourg, Strasbourg, France
| | - Judith A Burger
- Department of Medical Microbiology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
| | - Anna Schorcht
- Department of Medical Microbiology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
| | - Rogier W Sanders
- Department of Medical Microbiology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands.,Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, NY, United States
| | - José L Carrascosa
- Department of Structure of Macromolecules, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Madrid, Spain
| | - Mariano Esteban
- Department of Molecular and Cellular Biology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Madrid, Spain
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5
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Gochev GG, Scoppola E, Campbell RA, Noskov BA, Miller R, Schneck E. β-Lactoglobulin Adsorption Layers at the Water/Air Surface: 3. Neutron Reflectometry Study on the Effect of pH. J Phys Chem B 2019; 123:10877-10889. [PMID: 31725291 DOI: 10.1021/acs.jpcb.9b07733] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Several characteristics of β-lactoglobulin (BLG) layers adsorbed at the air/water interface exhibit a strong pH dependence, but our knowledge on the underlying structure-property relations is still fragmental. Here, we therefore extend our recent studies by neutron reflectometry (NR) and provide a comprehensive overview through direct measurements of the surface excess Γ and the layers' molecular structure. This enables comparison with available literature data to draw general conclusions. The NR experiments were performed at various pH values and within a wide range of protein concentrations, CBLG. Adsorption kinetics measurements in air-contrast-matched-water and over a narrow Qz range enabled direct quantification of the dynamic surface excess Γ(t) and are found to be consistent with ellipsometry data. Near the isoelectric point, pI, the rates of adsorption and Γ are maximal but only at sufficiently high CBLG. NR data collected over a wider Qz range and in two aqueous isotopic contrasts revealed the structure of adsorbed BLG layers at a steady state close to equilibrium. Independent of the pH, BLG was found to form dense monolayers with average thicknesses of 1.1 nm, suggesting flattening of the BLG globules upon adsorption as compared with their bulk dimensions (≈3.5 nm). Near pI and at sufficiently high CBLG, a thick (≈5.5 nm) but looser secondary sublayer is additionally formed adjacent to the dense primary monolayer. The thickness of this sublayer can be interpreted in terms of disordered BLG dimers. The results obtained and notably the specific interfacial structuring of BLG near pI complement previous observations relating the impact of solution pH and CBLG on other interfacial characteristics such as surface pressure and surface dilational viscoelasticity modulus.
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Affiliation(s)
- Georgi G Gochev
- Max Planck Institute of Colloids and Interfaces , 14476 Potsdam , Germany.,Institute of Physical Chemistry , Bulgarian Academy of Sciences , 1113 Sofia , Bulgaria
| | - Ernesto Scoppola
- Max Planck Institute of Colloids and Interfaces , 14476 Potsdam , Germany
| | - Richard A Campbell
- Institut Laue-Langevin , 71 Avenue des Martyrs, CS20156 , 38042 Grenoble , France.,Division of Pharmacy and Optometry , University of Manchester , M13 9PT Manchester , U.K
| | - Boris A Noskov
- Institute of Chemistry , St. Petersburg State University , 198504 Saint-Petersburg , Russia
| | - Reinhard Miller
- Max Planck Institute of Colloids and Interfaces , 14476 Potsdam , Germany
| | - Emanuel Schneck
- Max Planck Institute of Colloids and Interfaces , 14476 Potsdam , Germany
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6
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Qi PX, Chau HK, Hotchkiss AT. Molecular characterization of interacting complexes and conjugates induced by the dry-state heating of β-lactoglobulin and sugar beet pectin. Food Hydrocoll 2019. [DOI: 10.1016/j.foodhyd.2019.01.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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7
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Investigation of the molecular interactions between β-lactoglobulin and low methoxyl pectin by multi-detection High Performance Size Exclusion Chromatography. Food Hydrocoll 2017. [DOI: 10.1016/j.foodhyd.2016.09.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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8
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Eissa S, Zourob M. In vitro selection of DNA aptamers targeting β-lactoglobulin and their integration in graphene-based biosensor for the detection of milk allergen. Biosens Bioelectron 2016; 91:169-174. [PMID: 28006685 DOI: 10.1016/j.bios.2016.12.020] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 12/04/2016] [Accepted: 12/08/2016] [Indexed: 01/02/2023]
Abstract
Food allergy has increased rapidly in recent years affecting millions of people worldwide. With the increased consumption of packed food nowadays, a sensitive, accurate and rapid screening method for potential food allergens has become an urgent need in order to protect the sensitive consumers from life-threatening reactions. The current detection methods for food allergens are mostly based on immunoassays which are costly and times-consuming. In this work, we developed an aptamer/graphene-based electrochemical biosensor for on-step, sensitive and low cost detection of β-lactoglobulin (β-LG) milk protein, one of the most common food allergens specially in infants. The selection of DNA aptamers against the two β-LG variants A and B was successfully realised using systemic evolution of ligands by exponential enrichment (SELEX) method. Among the selected aptamers, BLG14 aptamer sequence has shown high affinity and specificity to both β-LG A and B with dissociation constants (Kds) of 82 and 80nM, respectively as calculated using fluorescence binding assays. The aptamer was then integrated in a voltammetric biosensor utilizing graphene-modified screen printed carbon electrodes. The binding is monitored by following the change in the square wave voltammetry (SWV) reduction peak signal of ferrocyanide/ferricyanide redox couple due to the removal of the negatively charged aptamers from the surface upon protein binding. This one-step "signal on" biosensor takes 20min for the sensitive and selective detection of β-LG without using any labelling or sophisticated designs. The method was also tested in spiked food sample extract achieving good recovery percentage. The integration of the novel aptamer in the graphene biosensor allows a promising way for cost-effective, rapid and sensitive on-site detection of milk allergen in food stuff.
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Affiliation(s)
- Shimaa Eissa
- Department of Chemistry, Alfaisal University, Al Zahrawi Street, Al Maather, Al Takhassusi Road, Riyadh 11533, Saudi Arabia
| | - Mohammed Zourob
- Department of Chemistry, Alfaisal University, Al Zahrawi Street, Al Maather, Al Takhassusi Road, Riyadh 11533, Saudi Arabia; King Faisal Specialist Hospital and Research Center, Zahrawi Street, Al Maather, Riyadh 12713, Saudi Arabia.
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9
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Kujda M, Adamczyk Z, Zapotoczny S, Kowalska E. Electrokinetic characteristics of HSA dimer and its monolayers at mica. Colloids Surf B Biointerfaces 2015; 136:1207-14. [DOI: 10.1016/j.colsurfb.2015.11.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Revised: 09/29/2015] [Accepted: 11/02/2015] [Indexed: 11/28/2022]
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10
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Ruiz-Valdepeñas Montiel V, Campuzano S, Conzuelo F, Torrente-Rodríguez RM, Gamella M, Reviejo AJ, Pingarrón JM. Electrochemical magnetoimmunosensing platform for determination of the milk allergen β-lactoglobulin. Talanta 2014; 131:156-62. [PMID: 25281087 DOI: 10.1016/j.talanta.2014.07.076] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 07/23/2014] [Accepted: 07/27/2014] [Indexed: 11/30/2022]
Abstract
A very sensitive magnetoimmunosensor for the determination of β-lactoglobulin (β-LG) is reported in this work. A sandwich configuration involving covalent immobilization of the capture antibody (antiβ-LG) onto activated carboxylic-modified magnetic beads (HOOC-MBs) and incubation of the modified MBs with a horseradish peroxidase labeled antibody (HRP-antiβ-LG), is used. The resulting modified MBs are captured by a magnet placed under the surface of a disposable carbon screen-printed electrode (SPCE) and the amperometric responses are measured at -0.20 V (vs. Ag pseudo-reference electrode), upon addition of hydroquinone (HQ) as electron transfer mediator and H2O2 as the enzyme substrate. The β-LG magnetoimmunosensor exhibited a wide range of linearity (2.8-100 ng mL(-1)) and a low detection limit of 0.8 ng mL(-1) (20 pg in 25 μL sample). The magnetoimmunosensing platform was successfully applied for the detection of β-LG in different types of milk without any matrix effect after just a sample dilution. The results correlated properly with those provided by a commercial ELISA method offering a truthful analytical screening tool. These features make the developed methodology a promising alternative in the development of user-friendly devices for on-site determination of β-LG in dairy products.
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Affiliation(s)
- V Ruiz-Valdepeñas Montiel
- Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain.
| | - S Campuzano
- Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain.
| | - F Conzuelo
- Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain.
| | - R M Torrente-Rodríguez
- Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain.
| | - M Gamella
- Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain.
| | - A J Reviejo
- Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain.
| | - José M Pingarrón
- Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain.
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11
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Qi PX, Chau HK, Fishman ML, Wickham ED, Hotchkiss AT. Investigation of molecular interactions between β-lactoglobulin and sugar beet pectin by multi-detection HPSEC. Carbohydr Polym 2014; 107:198-208. [DOI: 10.1016/j.carbpol.2014.02.080] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Revised: 02/15/2014] [Accepted: 02/24/2014] [Indexed: 12/23/2022]
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12
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β-Lactoglobulin conformation and mixed sugar beet pectin gel matrix is changed by laccase. Lebensm Wiss Technol 2014. [DOI: 10.1016/j.lwt.2013.07.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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13
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Alaidarous M, Ve T, Casey LW, Valkov E, Ericsson DJ, Ullah MO, Schembri MA, Mansell A, Sweet MJ, Kobe B. Mechanism of bacterial interference with TLR4 signaling by Brucella Toll/interleukin-1 receptor domain-containing protein TcpB. J Biol Chem 2013; 289:654-68. [PMID: 24265315 DOI: 10.1074/jbc.m113.523274] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Upon activation of Toll-like receptors (TLRs), cytoplasmic Toll/interleukin-1 receptor (TIR) domains of the receptors undergo homo- or heterodimerization. This in turn leads to the recruitment of adaptor proteins, activation of transcription factors, and the secretion of pro-inflammatory cytokines. Recent studies have described the TIR domain-containing protein from Brucella melitensis, TcpB (BtpA/Btp1), to be involved in virulence and suppression of host innate immune responses. TcpB interferes with TLR4 and TLR2 signaling pathways by a mechanism that remains controversial. In this study, we show using co-immunoprecipitation analyses that TcpB interacts with MAL, MyD88, and TLR4 but interferes only with the MAL-TLR4 interaction. We present the crystal structure of the TcpB TIR domain, which reveals significant structural differences in the loop regions compared with other TIR domain structures. We demonstrate that TcpB forms a dimer in solution, and the crystal structure reveals the dimerization interface, which we validate by mutagenesis and biophysical studies. Our study advances the understanding of the molecular mechanisms of host immunosuppression by bacterial pathogens.
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14
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Roy R, Usha V, Kermani A, Scott DJ, Hyde EI, Besra GS, Alderwick LJ, Fütterer K. Synthesis of α-glucan in mycobacteria involves a hetero-octameric complex of trehalose synthase TreS and Maltokinase Pep2. ACS Chem Biol 2013; 8:2245-55. [PMID: 23901909 PMCID: PMC3805332 DOI: 10.1021/cb400508k] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
![]()
Recent evidence established that
the cell envelope of Mycobacterium
tuberculosis, the bacillus causing tuberculosis (TB), is
coated by an α-glucan-containing capsule that has been implicated
in persistence in a mouse infection model. As one of three known metabolic
routes to α-glucan in mycobacteria, the cytoplasmic GlgE-pathway
converts trehalose to α(1 → 4),α(1 → 6)-linked
glucan in 4 steps. Whether individual reaction steps, catalyzed by
trehalose synthase TreS, maltokinase Pep2, and glycosyltransferases
GlgE and GlgB, occur independently or in a coordinated fashion is
not known. Here, we report the crystal structure of M. tuberculosis TreS, and show by small-angle X-ray scattering and analytical ultracentrifugation
that TreS forms tetramers in solution. Together with Pep2, TreS forms
a hetero-octameric complex, and we demonstrate that complex formation
markedly accelerates maltokinase activity of Pep2. Thus, complex formation
may act as part of a regulatory mechanism of the GlgE pathway, which
overall must avoid accumulation of toxic pathway intermediates, such
as maltose-1-phosphate, and optimize the use of scarce nutrients.
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Affiliation(s)
- Rana Roy
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15
2TT, U.K
| | - Veeraraghavan Usha
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15
2TT, U.K
| | - Ali Kermani
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15
2TT, U.K
| | - David J. Scott
- School of Biosciences, University of Nottingham, Sutton Bonington Campus,
Sutton Bonington LE12 5RD, U.K
- Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell, Oxon OX11
0FA, U.K
| | - Eva I. Hyde
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15
2TT, U.K
| | - Gurdyal S. Besra
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15
2TT, U.K
| | - Luke J. Alderwick
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15
2TT, U.K
| | - Klaus Fütterer
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15
2TT, U.K
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15
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Electrochemical immunosensor for the milk allergen β-lactoglobulin based on electrografting of organic film on graphene modified screen-printed carbon electrodes. Biosens Bioelectron 2012; 38:308-13. [DOI: 10.1016/j.bios.2012.06.008] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Revised: 06/05/2012] [Accepted: 06/06/2012] [Indexed: 11/17/2022]
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16
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Rossier-Miranda FJ, Schroën K, Boom R. Microcapsule production by an hybrid colloidosome-layer-by-layer technique. Food Hydrocoll 2012. [DOI: 10.1016/j.foodhyd.2011.08.007] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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17
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Patois E, Capelle M, Palais C, Gurny R, Arvinte T. Evaluation of nanoparticle tracking analysis (NTA) in the characterization of therapeutic antibodies and seasonal influenza vaccines: pros and cons. J Drug Deliv Sci Technol 2012. [DOI: 10.1016/s1773-2247(12)50069-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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18
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Mamluk R, Carvajal IM, Morse BA, Wong H, Abramowitz J, Aslanian S, Lim AC, Gokemeijer J, Storek MJ, Lee J, Gosselin M, Wright MC, Camphausen RT, Wang J, Chen Y, Miller K, Sanders K, Short S, Sperinde J, Prasad G, Williams S, Kerbel R, Ebos J, Mutsaers A, Mendlein JD, Harris AS, Furfine ES. Anti-tumor effect of CT-322 as an adnectin inhibitor of vascular endothelial growth factor receptor-2. MAbs 2011; 2:199-208. [PMID: 20190562 DOI: 10.4161/mabs.2.2.11304] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
CT-322 is a new anti-angiogenic therapeutic agent based on an engineered variant of the tenth type III domain of human fibronectin, i.e., an Adnectin™, designed to inhibit vascular endothelial growth factor receptor (VEGFR)-2. This PE Gylated Adnectin was developed using an mRNA display technology. CT-322 bound human VEGFR-2 with high affinity (K(D), 11 nM), but did not bind VEGFR-1 or VEGFR-3 at concentrations up to 100 nM, as determined by surface plasmon resonance studies. Western blot analysis showed that CT-322 blocked VEGF-induced phosphorylation of VEGFR-2 and mitogen-activated protein kinase in human umbilical vascular endothelial cells. CT-322 significantly inhibited the growth of human tumor xenograft models of colon carcinoma and glioblastoma at doses of 15-60 mg/kg administered 3 times/week. Anti-tumor effects of CT-322 were comparable to those of sorafenib or sunitinib, which inhibit multiple kinases, in a colon carcinoma xenograft model, although CT-322 caused less overt adverse effects than the kinase inhibitors. CT-322 also enhanced the anti-tumor activity of the chemotherapeutic agent temsirolimus in the colon carcinoma model. The high affinity and specificity of CT-322 binding to VEGFR-2 and its anti-tumor activities establish CT-322 as a promising anti-angiogenic therapeutic agent. Our results further suggest that Adnectins are an important new class of targeted biologics that can be developed as potential treatments for a wide variety of diseases.
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Affiliation(s)
- Roni Mamluk
- Adnexus, A Bristol Myers Squibb R&D Company, Waltham, MA, USA
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19
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Henck S, Treacy E, Yang J. Mixing-induced aggregation and associated microstructures in the capillary flow. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2009; 80:026306. [PMID: 19792248 DOI: 10.1103/physreve.80.026306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2009] [Indexed: 05/28/2023]
Abstract
With a device that uses microscopic imaging as the signal detection method for online laser light scattering of solutions driven to flow in a capillary tube, we have found that mixing of a solution with water and vice versa induce large numbers of aggregates in the free flow stream. The degrees of aggregation as measured from the total number of aggregates and the corresponding light-scattering intensities are dependent on the species of the solution. This species dependence of the mixing aggregation in the capillary flow has the potential for the development of new protocols or even spectroscopic methods for the detection of solute molecules and the assessment of solution qualities. Furthermore, even with pure-distilled and de-ionized water in the steady-state capillary flow, there are still countable numbers of aggregates detectable in the free flow stream, although of extremely low concentration of an estimated value of no more than 10(-15) M .
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Affiliation(s)
- Steven Henck
- Physics Department, University of Vermont, Burlington, Vermont 05405, USA
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20
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Schaink H, Smit J. Protein–polysaccharide interactions: The determination of the osmotic second virial coefficients in aqueous solutions of β-lactoglobulin and dextran. Food Hydrocoll 2007. [DOI: 10.1016/j.foodhyd.2006.10.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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21
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Castelletto V, Krysmann MJ, Clifton LA, Lambourne J, Noirez L. Structural Study of BSA/Poly(ethylene glycol) Lipid Conjugate Complexes. J Phys Chem B 2007; 111:11330-6. [PMID: 17803303 DOI: 10.1021/jp074409n] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this work we report the structural characteristics of bovine serum albumin/poly(ethylene glycol) lipid conjugate (BSA/PEG(2000)-PE) complexes under physiological conditions (37 degrees C and pH 7.4) for particular fractions of BSA to PEG-lipid concentration, c(BSA)/c(PEG)(2000)-PE. Ultraviolet fluorescence spectroscopy (UV) results shown that PEG(2000)-PE is associated to BSA, leading to protein unfolding for fixed c(BSA) = 0.01 wt % and variable c(PEG)(2000)-PE = 0.0015-0.6 wt %. Tryptophan groups on the BSA surface are in contact with the PEG-lipid at c(PEG)(2000)-PE = 0.0015 wt %, while they are exposed to water at c(PEG)(2000)-PE > 0.0015 wt %. Dynamic and static light scattering (DLS and SLS) and small-angle neutron scattering (SANS) point out the existence of individual BSA/PEG-lipid complexes in the system for fixed c(BSA) = 1 wt % and variable c(PEG)(2000)-PE = 0.15-2 wt %. DLS shows that there is only one BSA molecule per protein/PEG-lipid complex, while SLS shows that the PEG-lipid associates to the BSA without promoting aggregation between adjacent protein/polymer-lipid conjugate complexes. SANS was used to show that BSA/PEG(2000)-PE complexes adopt an oblate ellipsoidal shape. Partially unfolded BSA is contained in the core of the oblate ellipsoid, which is surrounded by an external shell containing the PEG(2000)-PE.
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Affiliation(s)
- Valeria Castelletto
- School of Chemistry, Food Biosciences and Pharmacy, The University of Reading, PO BOX 226, Whiteknights, Reading RG6 6AP, United Kingdom.
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22
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Moriarty DF, Fiorillo C, Miller C, Colón W. A truncated peptide model of the mutant P61A FIS forms a stable dimer. BIOCHIMICA ET BIOPHYSICA ACTA 2007; 1774:78-85. [PMID: 17118726 DOI: 10.1016/j.bbapap.2006.09.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2006] [Revised: 09/13/2006] [Accepted: 09/19/2006] [Indexed: 05/12/2023]
Abstract
Factor for inversion stimulation (FIS) is a 98-residue homodimeric DNA-binding protein involved in several different cellular processes including DNA inversion and the regulation of multiple genes. FIS contains a flexible and functionally important N-terminus followed by four helices (A-D), the last two of which consist of the DNA-binding region. Helix B, which comprises the main dimerization interface has a 20 degrees kink at its center that was originally thought to be caused by the presence of a proline at position 61. However, it was later shown that the kink remained largely intact and that FIS retained its native-like function when the proline was mutated to an alanine. We previously showed that the P61A mutation increased the stability of FIS, but decreased its equilibrium denaturation cooperativity apparently due to preferential stabilization of the B-helix. Here we studied a peptide of P61A FIS, corresponding to residues 26-71 (26-71(A3) FIS), which encompasses the dimer interface (helices A and B). Circular dichroism (CD) and size-exclusion chromatography/multi-angle light scattering showed that the peptide was alpha-helical and dimeric, respectively, as expected based on the 3D structure of FIS. Urea-induced equilibrium denaturation experiments monitored by far-UV CD revealed a concentration-dependent transition, and data analysis based on a N2<-->2U model yielded a DeltaG of approximately -10 kcal/mol. Our results suggest that 26-71(A3) FIS can form a stable dimeric structure despite lacking the N- and C-terminus of native FIS.
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Affiliation(s)
- Daniel F Moriarty
- Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
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23
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Majhi PR, Ganta RR, Vanam RP, Seyrek E, Giger K, Dubin PL. Electrostatically driven protein aggregation: beta-lactoglobulin at low ionic strength. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2006; 22:9150-9. [PMID: 17042523 DOI: 10.1021/la053528w] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The aggregation of beta-lactoglobulin (BLG) at ambient temperature was studied using turbidimetry and dynamic light scattering in the range 3.8<pH<5.2 in 0.0045 M NaCl, and in the ionic strength range 0.0045-0.5 M at fixed pH=5.0. The initial rate of aggregation, taken as the initial slope of turbidity vs time, (dtau/dt)0, indicated maximum aggregation near pH 4.6 (below the isoelectric point of 5.2), but the dependence of the initial rate of aggregation on pH was highly asymmetric. At pH 5.0, (dtau/dt)0 strongly increased with a decrease in ionic strength I from 0.1 to 0.0045 M and was found to be nearly linear with 1/I. DLS measurements revealed an increase in particle size with time, with the appearance of bimodal distributions in which the fast and slow modes corresponded, respectively, to a BLG dimer and to larger aggregates in the 100-800 nm range. At conditions of slower aggregation, DLS revealed the consumption of dimers to form higher order aggregates with no intermediate species. Computer modeling (Delphi) was used to visualize the electrostatic potential around the dimer to elucidate the pH and ionic strength dependence of the initial aggregation rates. The aggregation process appears to comprise an initial fast consumption of the dimer, whose dependence on pH and I arises from the interaction of the positive and negative domains of interacting dimers, followed by the slow formation of much larger aggregates with relatively little sensitivity to pH and I. The open-ended nature of BLG aggregation is thought to arise from the asymmetry of the dimer charge distribution.
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Affiliation(s)
- Pinaki R Majhi
- Department of Chemistry, Indiana University-Purdue University at Indianapolis, 402 North Blackford Street, Indianapolis, Indiana 46202, USA
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24
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Hattori T, Bat-Aldar S, Kato R, Bohidar HB, Dubin PL. Characterization of polyanion-protein complexes by frontal analysis continuous capillary electrophoresis and small angle neutron scattering: effect of polyanion flexibility. Anal Biochem 2005; 342:229-36. [PMID: 15949785 DOI: 10.1016/j.ab.2005.03.043] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2005] [Revised: 03/21/2005] [Accepted: 03/24/2005] [Indexed: 11/29/2022]
Abstract
The binding constant (K(obs)) for the beta-lactoglobulin-poly(vinylsulfate) (BLG-PVS) complex was measured by frontal analysis continuous capillary electrophoresis at pH values above the isoelectric point of BLG, and the persistence length (L(p)) of PVS was measured by small angle neutron scattering, to examine the effect of polyelectrolyte chain stiffness on its binding efficiency to proteins. The values of K(obs) and L(p) were compared with those of BLG-PSS and BLG-PAMPS (poly(2-acrylamido-2-methylpropanesulfonate)) reported previously. The relationship between K(obs) and L(p) was reciprocal, indicating that protein binding is enhanced by the flexibility of the polyanion, at least in the case where the net protein charge is negative. In addition, at a fixed pH, the polymer systems displayed a similar ionic strength dependence of K(obs). This similarity was consistent with the proposal that the binding properties of PVS and PAMPS polyanions are governed purely by electrostatic interactions and are independent of their molecular structure.
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Affiliation(s)
- Toshiaki Hattori
- Department of Materials Science, Toyohashi University of Technology, Toyohashi 441-8580, Japan
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25
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Abstract
Bioseparation processes are dominated by chromatographic steps. Even primary recovery is sometimes accomplished by chromatographic separation, using a fluidized bed instead of a fixed bed. In this review, the action principles, features of chromatography media regarding physical and chemical properties will be described. An attempt will be made to establish categories of different media. Characteristics for bioseparation are the large pores and particle sizes. To achieve sufficient capacity for ultralarge molecules, such as plasmids or nanoparticles, such as viruses monoliths are the media of choice. In these media, the mass transport is accomplished by convection, and thus, the low diffusivity can be overcome. Common to all modern chromatography media is the fast operation. There are examples where a residence time of less then 3 min, is sufficient to reach the full potential of the adsorbent.
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Affiliation(s)
- Alois Jungbauer
- Department of Biotechnology, University of Natural Resources and Applied Life Science, A-1190 Vienna, Austria.
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26
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Ahrer K, Buchacher A, Iberer G, Josic D, Jungbauer A. Analysis of aggregates of human immunoglobulin G using size-exclusion chromatography, static and dynamic light scattering. J Chromatogr A 2004; 1009:89-96. [PMID: 13677648 DOI: 10.1016/s0021-9673(03)00433-3] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Large aggregates (Mr: 10(6)-10(7) g/mol) of human immunoglobulins are present in extremely small concentrations in IgG preparations (<0.1%). Traces of large protein aggregates cannot be determined by conventional size-exclusion chromatography (SEC) using UV detection due to limitations in sensitivity. The conventional analysis of IgG by SEC is limited to dimers and oligomers. Using light scattering it is possible to determine significant differences concerning the aggregate composition and the extent of protein aggregation in samples of different process steps. Two different pilot preparations were analyzed by SEC with UV and static light scattering detection and compared to dynamic light scattering in the batch mode. The change of large aggregates could be monitored and data were corroborated by dynamic light scattering.
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Affiliation(s)
- K Ahrer
- Institute of Applied Microbiology, University of Natural Resources and Applied Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
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27
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Arfvidsson C, Wahlund KG, Eliasson AC. Direct molecular weight determination in the evaluation of dissolution methods for unreduced glutenin. J Cereal Sci 2004. [DOI: 10.1016/s0733-5210(03)00038-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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28
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Stulík K, Pacáková V, Tichá M. Some potentialities and drawbacks of contemporary size-exclusion chromatography. JOURNAL OF BIOCHEMICAL AND BIOPHYSICAL METHODS 2003; 56:1-13. [PMID: 12834966 DOI: 10.1016/s0165-022x(03)00053-8] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The present state of the chromatographic techniques based on differentiation of solutes according to their molecular sizes is briefly surveyed. Attention is centred on high-performance techniques applied to purification and characterization of natural macromolecules, and on discussion of the chromatographic approaches to the determination of the molecular masses and molecular mass distributions of both natural and synthetic polymers. The basic requirements on the selection of the separation system and the experimental conditions are summarized, demonstrated on a few examples and critically evaluated.
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Affiliation(s)
- Karel Stulík
- Department of Analytical Chemistry, Faculty of Science, Charles University in Prague, Albertov 2030, 128 40 Prague 2, Czech Republic
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29
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Wang S, van Dijk JA, Odijk T, Smit JA. Depletion-induced demixing in aqueous protein-polysaccharide solutions. Biomacromolecules 2003; 2:1080-8. [PMID: 11777377 DOI: 10.1021/bm010001z] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We explore the separation of aqueous protein-polysaccharide solutions into two liquid phases. In particular, we have studied the combinations beta-lactoglobulin/pullulan, alpha-lactalbumin/pullulan, and other examples from the literature under a variety of conditions such as varying salt content, pH (in most cases at the isoelectric point), and protein radius. We restrict ourselves to relatively small proteins (globular) and long polysaccharide chains. The mechanism behind the phase separation is explained in terms of the depletion interaction (i.e., the cross-interaction) in a suspension of small spheres (proteins) immersed in a semidilute solution of coils (polysaccharide) forming an entangled network. Weak attractions between the spheres have been taken into account by assuming the formation of small clusters. As a general rule, we find that the depletion free energy per protein particle governing the protein partitioning in the phase equilibrium is linear in the polysaccharide concentration over the whole range of experimentally accessible coexistence curves. Furthermore, the proportionality constant is shown to be a very useful quantity to understand the characteristics of the coexistence curves. The linearity thus found is supported by theoretical arguments developed by de Gennes and Odijk.
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Affiliation(s)
- S Wang
- Colloid and Interface Science Group, LIC, Gorlaeus Labs, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands
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30
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Levi V, González Flecha FL. Reversible fast-dimerization of bovine serum albumin detected by fluorescence resonance energy transfer. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1599:141-8. [PMID: 12479415 DOI: 10.1016/s1570-9639(02)00414-4] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Self-association of bovine serum albumin (BSA) was explored using fluorescence resonance energy transfer (FRET) between two populations of the protein labeled separately with either fluorescein-5'-isothiocyanate (FITC) or eosin-5'-isothiocyanate (EITC). The energy transfer reached the steady state after 5 s at 25 degrees C, indicating a fast exchange between oligomer subunits. The dependence of the energy transfer efficiency on the protein concentration and its reversion by unlabeled BSA demonstrate that association between BSA monomers occurs through a reversible path that involves specific interactions between the protein molecules. Because energy transfer took place even after blocking Cys 34 with iodoacetamide, this residue might not be involved in the reversible self-association process. The number of subunits forming the oligomer and its dissociation constant were determined from measurements of energy transfer as a function of the donor-acceptor ratio and of the total protein concentration. Analysis of these data indicated that BSA is in a monomer-dimer equilibrium with a dissociation constant of 10 +/- 2 microM at 25 degrees C in 10 mM MOPS-K (pH 5.8).
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Affiliation(s)
- Valeria Levi
- Departamento de Química Biológica, Instituto de Química y Fisicoquímica Biológicas, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junin 956, 1113, Buenos Aires, Argentina
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31
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Yamaguchi T, Adachi K. Hemoglobin equilibrium analysis by the multiangle laser light-scattering method. Biochem Biophys Res Commun 2002; 290:1382-7. [PMID: 11820774 DOI: 10.1006/bbrc.2002.6362] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Dimer-tetramer and monomer-dimer-tetramer equilibria of tetrameric hemoglobins and their single chains in the CO form, respectively, were evaluated using the microbatch multiangle light-scattering (MALS) analysis system. The molecular weights of human Hb A and Hb F in the CO form were dependent on concentration. The dissociation constants to dimers of Hb A and Hb F were 2.58 x 10(-6) and 0.66 x 10(-6), respectively. Equilibration of single globin chains, including alpha, beta, and gamma chains, was also evaluated by the same method. The dissociation constants of alpha-chain dimers to monomers, of beta-chain tetramers to monomers, and of gamma-chain tetramers to dimers were 14 x 10(-6), 25 x 10(-17), and 6.86 x 10(-6) M, respectively. These results indicate that the MALS analysis system can not only determine molecular weight but also characterize protein-protein interactions of multi-subunit proteins.
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Affiliation(s)
- Takamasa Yamaguchi
- Division of Hematology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA
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32
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Bean SR, Lookhart GL. Factors Influencing the Characterization of Gluten Proteins by Size-Exclusion Chromatography and Multiangle Laser Light Scattering (SEC-MALLS). Cereal Chem 2001. [DOI: 10.1094/cchem.2001.78.5.608] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- S. R. Bean
- Dept. Grain Science and Industry, Kansas State University, Manhattan, KS 66506
| | - G. L. Lookhart
- USDA-ARS, Grain Marketing and Production Research Center and Kansas State University. Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by the USDA implies no approval of the product to the exclusion of others that may also be suitable
- Corresponding author. E-mail: Phone: 785-776-2376. Fax: 785-776-2792
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