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Ayoub N, Roth P, Ucurum Z, Fotiadis D, Hirschi S. Structural and biochemical insights into His-tag-induced higher-order oligomerization of membrane proteins by cryo-EM and size exclusion chromatography. J Struct Biol 2023; 215:107924. [PMID: 36462717 DOI: 10.1016/j.jsb.2022.107924] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Revised: 11/18/2022] [Accepted: 11/26/2022] [Indexed: 12/05/2022]
Abstract
Structural and functional characterization of proteins as well as the design of targeted drugs heavily rely on recombinant protein expression and purification. The polyhistidine-tag (His-tag) is among the most prominent examples of affinity tags used for the isolation of recombinant proteins from their expression hosts. Short peptide tags are commonly considered not to interfere with the structure of the tagged protein and tag removal is frequently neglected. This study demonstrates the formation of higher-order oligomers based on the example of two His-tagged membrane proteins, the dimeric arginine-agmatine antiporter AdiC and the pentameric light-driven proton pump proteorhodopsin. Size exclusion chromatography revealed the formation of tetrameric AdiC and decameric as well as pentadecameric proteorhodopsin through specific interactions between their His-tags. In addition, single particle cryo-electron microscopy (cryo-EM) allowed structural insights into the three-dimensional arrangement of the higher-order oligomers and the underlying His-tag-mediated interactions. These results reinforce the importance of considering the length and removal of affinity purification tags and illustrate how neglect can lead to potential interference with downstream biophysical or biochemical characterization of the target protein.
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Affiliation(s)
- Nooraldeen Ayoub
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland
| | - Patrick Roth
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland
| | - Zöhre Ucurum
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland
| | - Dimitrios Fotiadis
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland.
| | - Stephan Hirschi
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland.
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2
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Affinity of Phenolic Compounds for Transition Metal Ions Immobilized on Cation-Exchange Columns. J Chromatogr A 2022; 1676:463277. [DOI: 10.1016/j.chroma.2022.463277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 05/15/2022] [Accepted: 06/22/2022] [Indexed: 11/21/2022]
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3
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Javanshad R, Venter AR. Effects of amino acid additives on protein solubility - insights from desorption and direct electrospray ionization mass spectrometry. Analyst 2021; 146:6592-6604. [PMID: 34586125 DOI: 10.1039/d1an01392k] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Naturally occurring amino acids have been broadly used as additives to improve protein solubility and inhibit aggregation. In this study, improvements in protein signal intensity obtained with the addition of L-serine, and structural analogs, to the desorption electrospray ionization mass spectrometry (DESI-MS) spray solvent were measured. The results were interpreted at the hand of proposed mechanisms of solution additive effects on protein solubility and dissolution. DESI-MS allows for these processes to be studied efficiently using dilute concentrations of additives and small amounts of proteins, advantages that represent real benefits compared to classical methods of studying protein stability and aggregation. We show that serine significantly increases the protein signal in DESI-MS when native proteins are undergoing unfolding during the dissolution process with an acidic solvent system (p-value = 0.0001), or with ammonium bicarbonate under denaturing conditions for proteins with high isoelectric points (p-value = 0.001). We establish that a similar increase in the protein signal cannot be observed with direct ESI-MS, and the observed increase is therefore not related to ionization processes or changes in the physical properties of the bulk solution. The importance of the presence of serine during protein conformational changes while undergoing dissolution is demonstrated through comparisons between the analyses of proteins deposited in native or unfolded states and by using native state-preserving and denaturing desorption solvents. We hypothesize that direct, non-covalent interactions involving all three functional groups of serine are involved in the beneficial effect on protein solubility and dissolution. Supporting evidence for a direct interaction include a reduction in efficacy with D-serine or the racemic mixture, indicating a non-bulk-solution physical property effect; insensitivity to the sample surface type or relative placement of serine addition; and a reduction in efficacy with any modifications to the serine structure, most notably the carboxyl functional group. An alternative hypothesis, also supported by some of our observations, could involve the role of serine clusters in the mechanism of solubility enhancement. Our study demonstrates the capability of DESI-MS together with complementary ESI-MS experiments as a novel tool for understanding protein solubility and dissolution and investigating the mechanism of action for solubility-enhancing additives.
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Affiliation(s)
- Roshan Javanshad
- Department of Chemistry, Western Michigan University, Kalamazoo, MI 49008-5413, USA.
| | - Andre R Venter
- Department of Chemistry, Western Michigan University, Kalamazoo, MI 49008-5413, USA.
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4
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Zhao L, Li S, Wang W, Wang Y, Du K. Preparation and characterization of highly porous cellulose-agarose composite chromatographic microspheres for enhanced selective separation of histidine-rich proteins. J Chromatogr A 2020; 1637:461831. [PMID: 33373794 DOI: 10.1016/j.chroma.2020.461831] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 12/09/2020] [Accepted: 12/16/2020] [Indexed: 10/22/2022]
Abstract
In this work, the porous cellulose-agarose microspheres with high specific surface area and enhanced mechanical strength are prepared by a novel chemical crosslinking method. The crosslinking reaction homogeneously proceeds between polysaccharides, and the covalent bonding network is generated to replace the inherent hydrogen bonding network of cellulose. The prepared microspheres exhibit low crystallinity of 12.45%, which means high content of amorphous regions. The micro-meso-macroporous structure of microspheres in morphology is conducive to high permeability and adsorption capacity, and the microspheres possess high specific surface area of 183.81 m2/g. The affinity chromatographic microspheres are prepared by immobilizing Cu2+, which exhibits high adsorption capacity of 197.65 mg/g for bovine hemoglobin (BHb), fast adsorption rate wihin 40 minutes, well-selectivity, and excellent recyclability in ten cycles. We expect that this work to provide an outstanding candidate for the high performance of biomacromolecular purification.
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Affiliation(s)
- Liangshen Zhao
- Department of Pharmaceutical & Biological Engineering, School of Chemical Engineering, Sichuan University, Chengdu 610065, P. R. China
| | - Shasha Li
- Department of Pharmaceutical & Biological Engineering, School of Chemical Engineering, Sichuan University, Chengdu 610065, P. R. China
| | - Wenhui Wang
- Department of Pharmaceutical & Biological Engineering, School of Chemical Engineering, Sichuan University, Chengdu 610065, P. R. China
| | - Yinghong Wang
- Department of Pharmaceutical & Biological Engineering, School of Chemical Engineering, Sichuan University, Chengdu 610065, P. R. China
| | - Kaifeng Du
- Department of Pharmaceutical & Biological Engineering, School of Chemical Engineering, Sichuan University, Chengdu 610065, P. R. China.
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Wahab RA, Elias N, Abdullah F, Ghoshal SK. On the taught new tricks of enzymes immobilization: An all-inclusive overview. REACT FUNCT POLYM 2020. [DOI: 10.1016/j.reactfunctpolym.2020.104613] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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6
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Abstract
Dextran aldehyde (dexOx), resulting from the periodate oxidative cleavage of 1,2-diol moiety inside dextran, is a polymer that is very useful in many areas, including as a macromolecular carrier for drug delivery and other biomedical applications. In particular, it has been widely used for chemical engineering of enzymes, with the aim of designing better biocatalysts that possess improved catalytic properties, making them more stable and/or active for different catalytic reactions. This polymer possesses a very flexible hydrophilic structure, which becomes inert after chemical reduction; therefore, dexOx comes to be highly versatile in a biocatalyst design. This paper presents an overview of the multiple applications of dexOx in applied biocatalysis, e.g., to modulate the adsorption of biomolecules on carrier surfaces in affinity chromatography and biosensors design, to serve as a spacer arm between a ligand and the support in biomacromolecule immobilization procedures or to generate artificial microenvironments around the enzyme molecules or to stabilize multimeric enzymes by intersubunit crosslinking, among many other applications.
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Oriented Immobilization and Quantitative Analysis Simultaneously Realized in Sandwich Immunoassay via His-Tagged Nanobody. Molecules 2019; 24:molecules24101890. [PMID: 31100976 PMCID: PMC6572564 DOI: 10.3390/molecules24101890] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 05/08/2019] [Accepted: 05/13/2019] [Indexed: 01/28/2023] Open
Abstract
Despite the advantages of the nanobody, the unique structure limits its use in sandwich immunoassay. In this study, a facile protocol of sandwich immunoassay using the nanobody was established. In brief, β amyloid and SH2, an anti-β amyloid nanobody, were used as capture antibody and antigen, respectively. The SH2 fused with His-tag was first purified and absorbed on Co2+-NTA functional matrix and then immobilized through H2O2 oxidation of Co2+ to Co3+ under the optimized conditions. Then, 150 mM imidazole and 20 mM EDTA were introduced to remove the unbound SH2. The immobilized SH2 showed highly-sensitive detection of β amyloid. It is interesting that the quantification of the sandwich immunoassay was carried out by determining the His-tag of the detection nanobody, without interference from the His-tag of the capture nanobody. The immobilized SH2 detached exhibited outstanding stability during 30 days of storage. Taken together, His6-tag facilitated both the oriented immobilization of capture antibody and quantitative assay of detection antibody in sandwich immunoassay. We propose a facile and efficient sandwich immunoassay method that opens new avenue to the study of His-tagged protein interactions.
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Wang J, Guan H, Han Q, Tan S, Liang Q, Ding M. Fabrication of Yb 3+-Immobilized Hydrophilic Phytic-Acid-Coated Magnetic Nanocomposites for the Selective Separation of Bovine Hemoglobin from Bovine Serum. ACS Biomater Sci Eng 2019; 5:2740-2749. [PMID: 33405606 DOI: 10.1021/acsbiomaterials.9b00074] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In this work, Yb3+-immobilized hydrophilic phytic-acid-coated magnetic nanocomposites were prepared through a facile route and used to selectively separatrf bovine hemoglobin. Hydrophilic phytic acid (PA) was coated onto the magnetic Fe3O4-PEI via electrostatic interactions, followed by finally chelating with Yb3+ ions, which could produce specific protein binding sites at room temperature in water, and complex instrumentation was not necessary. The performance of as-prepared hybrids (Fe3O4-PEI-PA-Yb3+) was assessed by selectively isolating bovine hemoglobin (BHb). The obtained maximum binding capacity was 347.3 mg g-1. The retained BHb could be eluted under simple elution via using 0.1 M of Na2CO3, giving a recovery of 83%. Moreover, the generation of nanocomposites was demonstrated. In addition, the PA and PEI could improve the hydrophilicity of nanoparticles and further reduce the nonspecific adsorption. Therefore, such nanocomposites were successfully employed to selectively bind and separate BHb from bovine serum as verified by SDS-PAGE and MALDI-TOF MS analysis, providing a new perspective for the isolation of heme proteins in proteomics.
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Affiliation(s)
- Jundong Wang
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Huiyuan Guan
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Qiang Han
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Siyuan Tan
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Qionglin Liang
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Mingyu Ding
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, China
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9
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Mohy Eldin MS, Abdel Rahman S, El Fawal GF. Novel immobilized Cu2+-aminated poly (methyl methacrylate) grafted cellophane membranes for affinity separation of His-Tag chitinase. Polym Bull (Berl) 2019. [DOI: 10.1007/s00289-019-02743-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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10
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Trang HK, Jiang L, Marcus RK. Grafting polymerization of glycidyl methacrylate onto capillary-channeled polymer (C-CP) fibers as a ligand binding platform: Applications in immobilized metal-ion affinity chromatography (IMAC) protein separations. J Chromatogr B Analyt Technol Biomed Life Sci 2019; 1110-1111:144-154. [DOI: 10.1016/j.jchromb.2019.02.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 01/28/2019] [Accepted: 02/11/2019] [Indexed: 01/28/2023]
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11
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Xu L, Wang R, Cao H, Xu T, Han L, Huang C, Jia L. A facile method to oriented immobilization of His-tagged BirA on Co3+-NTA agarose beads. Enzyme Microb Technol 2019; 120:36-42. [DOI: 10.1016/j.enzmictec.2018.09.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 09/10/2018] [Accepted: 09/17/2018] [Indexed: 12/11/2022]
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Nagy F, Tasnádi G, Balogh‐Weiser D, Bell E, Hall M, Faber K, Poppe L. Smart Nanoparticles for Selective Immobilization of Acid Phosphatases. ChemCatChem 2018; 10:3490-3499. [PMID: 30263083 PMCID: PMC6146910 DOI: 10.1002/cctc.201800405] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Indexed: 01/24/2023]
Abstract
An easy to use method combining the selectivity of metal chelate affinity binding with strong covalent linking was developed for immobilization of non-specific acid phosphatases bearing a His-tag from crude cell lysate. Silica nanoparticles were grafted with aminopropyl functions which were partially transformed further with EDTA dianhydride to chelators. The heterofunctionalized nanoparticles charged with Ni2+ as the most appropriate metal ion were applied as support. First, the His-tagged phosphatases were selectively bound to the metal-chelate functions of the support. Then, the enzyme-charged silica nanoparticles were further stabilized by forming a covalent linkage between nucleophilic moieties at the enzyme surface and free amino groups of the support using neopentylglycol diglycidylether as the most effective bifunctional linking agent. The phosphatase biocatalysts obtained by this method exhibited better phosphate transfer activity with a range of alcohols and PPi as phosphate donor in aqueous medium applying batch and continuous-flow modes than the ones immobilized on conventional supports. Furthermore, this novel strategy opens up novel possibility for efficient immobilization of other His-tagged recombinant enzymes.
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Affiliation(s)
- Flóra Nagy
- Department of Organic Chemistry and TechnologyBudapest University of Technology and EconomicsMűegyetem rkp. 31111BudapestHungary
| | - Gábor Tasnádi
- Austrian Centre of Industrial Biotechnology,c/oDepartment of Chemistry, Organic & Bioorganic ChemistryUniversity of GrazHeinrichstrasse 288010GrazAustria
- Department of Chemistry, Organic & Bioorganic ChemistryUniversity of GrazHeinrichstrasse 288010GrazAustria
| | - Diána Balogh‐Weiser
- Department of Organic Chemistry and TechnologyBudapest University of Technology and EconomicsMűegyetem rkp. 31111BudapestHungary
| | - Evelin Bell
- Department of Organic Chemistry and TechnologyBudapest University of Technology and EconomicsMűegyetem rkp. 31111BudapestHungary
| | - Mélanie Hall
- Department of Chemistry, Organic & Bioorganic ChemistryUniversity of GrazHeinrichstrasse 288010GrazAustria
| | - Kurt Faber
- Department of Chemistry, Organic & Bioorganic ChemistryUniversity of GrazHeinrichstrasse 288010GrazAustria
| | - László Poppe
- Department of Organic Chemistry and TechnologyBudapest University of Technology and EconomicsMűegyetem rkp. 31111BudapestHungary
- Biocatalysis and Biotransformation Research Center Faculty of Chemistry and Chemical EngineeringBabes-Bolyai University of Cluj-NapocaArany János str. 11400028Cluj-NapocaRomania
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13
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Ion concentration in micro and nanoscale electrospray emitters. Anal Bioanal Chem 2018; 410:3639-3648. [PMID: 29704029 DOI: 10.1007/s00216-018-1043-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 03/19/2018] [Accepted: 03/22/2018] [Indexed: 10/17/2022]
Abstract
Solution-phase ion transport during electrospray has been characterized for nanopipettes, or glass capillaries pulled to nanoscale tip dimensions, and micron-sized electrospray ionization emitters. Direct visualization of charged fluorophores during the electrospray process is used to evaluate impacts of emitter size, ionic strength, analyte size, and pressure-driven flow on heterogeneous ion transport during electrospray. Mass spectrometric measurements of positively- and negatively-charged proteins were taken for micron-sized and nanopipette emitters under low ionic strength conditions to further illustrate a discrepancy in solution-driven transport of charged analytes. A fundamental understanding of analyte electromigration during electrospray, which is not always considered, is expected to provide control over selective analyte depletion and enrichment, and can be harnessed for sample cleanup. Graphical abstract Fluorescence micrographs of ion migration in nanoscale pipettes while solution is electrosprayed.
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Verinaud CI, Feliciano GP, de Carvalho RR, Lopes APY, Raw I, Martins EAL, Cheng E. Purification of Plasma-Derived Coagulation Factor VIII by Immobilized-Zn2+ and -Co2+ Affinity Chromatography. Chromatographia 2017. [DOI: 10.1007/s10337-017-3345-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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15
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Novel immobilized Cu+2 ion grafted cellophane membranes for affinity separation of His-Tag Chitinase. ARAB J CHEM 2017. [DOI: 10.1016/j.arabjc.2014.04.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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16
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Karkra K, Tetala KK, Vijayalakshmi M. A structure based plasma protein pre-fractionation using conjoint immobilized metal/chelate affinity (IMA) system. J Chromatogr B Analyt Technol Biomed Life Sci 2017; 1052:1-9. [DOI: 10.1016/j.jchromb.2017.02.032] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 02/11/2017] [Accepted: 02/25/2017] [Indexed: 11/27/2022]
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17
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Selective Removal of Hemoglobin from Blood Using Hierarchical Copper Shells Anchored to Magnetic Nanoparticles. BIOMED RESEARCH INTERNATIONAL 2017; 2017:7309481. [PMID: 28316987 PMCID: PMC5339633 DOI: 10.1155/2017/7309481] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 01/29/2017] [Indexed: 12/02/2022]
Abstract
Hierarchical copper shells anchored on magnetic nanoparticles were designed and fabricated to selectively deplete hemoglobin from human blood by immobilized metal affinity chromatography. Briefly, CoFe2O4 nanoparticles coated with polyacrylic acid were first synthesized by a one-pot solvothermal method. Hierarchical copper shells were then deposited by immobilizing Cu2+ on nanoparticles and subsequently by reducing between the solid CoFe2O4@COOH and copper solution with NaBH4. The resulting nanoparticles were characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectrometry, X-ray photoelectron spectroscopy, and vibrating sample magnetometry. The particles were also tested against purified bovine hemoglobin over a range of pH, contact time, and initial protein concentration. Hemoglobin adsorption followed pseudo-second-order kinetics and reached equilibrium in 90 min. Isothermal data also fit the Langmuir model well, with calculated maximum adsorption capacity 666 mg g−1. Due to the high density of Cu2+ on the shell, the nanoparticles efficiently and selectively deplete hemoglobin from human blood. Taken together, the results demonstrate that the particles with hierarchical copper shells effectively remove abundant, histidine-rich proteins, such as hemoglobin from human blood, and thereby minimize interference in diagnostic and other assays.
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18
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Yao X, Ma X, Gao X, Jia L. Preparation of magnetic metal organic framework nanocomposites for efficient and selective adsorption of hemoglobin from bovine blood. RSC Adv 2017. [DOI: 10.1039/c7ra04397j] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Fe3O4@[Cu3(btc)2] particles were prepared and used for efficient and selective removal of abundant BHb from bovine blood.
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Affiliation(s)
- Xin Yao
- Ministry of Education Key Laboratory of Laser Life Science & Institute of Laser Life, Science
- College of Biophotonics
- South China Normal University
- Guangzhou 510631
- China
| | - Xiangdong Ma
- Ministry of Education Key Laboratory of Laser Life Science & Institute of Laser Life, Science
- College of Biophotonics
- South China Normal University
- Guangzhou 510631
- China
| | - Xiaomei Gao
- Ministry of Education Key Laboratory of Laser Life Science & Institute of Laser Life, Science
- College of Biophotonics
- South China Normal University
- Guangzhou 510631
- China
| | - Li Jia
- Ministry of Education Key Laboratory of Laser Life Science & Institute of Laser Life, Science
- College of Biophotonics
- South China Normal University
- Guangzhou 510631
- China
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19
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Mortensen DN, Williams ER. Electrothermal supercharging of proteins in native MS: effects of protein isoelectric point, buffer, and nanoESI-emitter tip size. Analyst 2016; 141:5598-606. [PMID: 27441318 PMCID: PMC5239670 DOI: 10.1039/c6an01380e] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The extent of charging resulting from electrothermal supercharging for protein ions formed from various buffered aqueous solutions using nanoESI emitters with tip diameters between ∼1.5 μm and ∼310 nm is compared. Charging increases with decreasing tip size for proteins that are positively charged in solution but not for proteins that are negatively charged in solution. These results suggest that Coulombic attraction between positively charged protein molecules and the negatively charged glass surfaces in the tips of the emitters causes destabilization and even unfolding of proteins prior to nanoESI. Coulombic attraction to the negatively charged glass surfaces does not occur for negatively charged proteins and the extent of charging with electrothermal supercharging decreases with decreasing tip size. Smaller droplets are formed with smaller tips, and these droplets have shorter lifetimes for protein unfolding with electrothermal supercharging to occur prior to gaseous ion formation. Results from this study demonstrate simple principles to consider in order to optimize the extent of charging obtained with electrothermal supercharging, which should be useful for obtaining more structural information in tandem mass spectrometry.
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Affiliation(s)
- Daniel N Mortensen
- Department of Chemistry, University of California, Berkeley, California 94720-1460, USA.
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20
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Mortensen DN, Williams ER. Surface-Induced Protein Unfolding in Submicron Electrospray Emitters. Anal Chem 2016; 88:9662-9668. [PMID: 27615434 DOI: 10.1021/acs.analchem.6b02499] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The charging of protein ions formed by nanoelectrospray ionization (nanoESI) with tips that are between 1.5 μm and 250 nm in outer diameter is compared. More charging is obtained with the smaller tip sizes for proteins that have a net positive charge in solution, and additional high-charge-state distributions are often observed. A single charge-state distribution of holo-myoglobin ions is produced by nanoESI from a slightly acidified aqueous solution with the micron outer diameter tips, but some apo-myoglobin ions are produced with the submicron tips. In contrast, the charge-state distributions for proteins with a net negative charge in solution do not depend on tip size. Both the formation of high charge states and the appearance of higher-charge-state distributions, as well as the loss of the heme group from myoglobin, indicate that a fraction of the protein population is unfolding with the smaller tips. The increased charging with the smaller tip sizes for proteins with a net positive charge but not for proteins with a net negative charge indicates that the unfolding occurs prior to nanoelectrospray ionization as a result of Coulombic attraction between positively charged protein molecules in solution and the glass surfaces of the emitter tips that are negatively charged. These results demonstrate a novel method for producing highly charged protein ions that does not require exposing the proteins to additional chemicals either in solution or in the gas phase.
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Affiliation(s)
- Daniel N Mortensen
- Department of Chemistry, University of California , Berkeley, California 94720-1460, United States
| | - Evan R Williams
- Department of Chemistry, University of California , Berkeley, California 94720-1460, United States
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21
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Kodal ALB, Rosen CB, Mortensen MR, Tørring T, Gothelf KV. DNA-Templated Introduction of an Aldehyde Handle in Proteins. Chembiochem 2016; 17:1338-42. [DOI: 10.1002/cbic.201600254] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Anne Louise B. Kodal
- Center for DNA Nanotechnology; Department of Chemistry and iNANO; Aarhus University; Gustav Wieds Vej14 8000 Aarhus C Denmark
| | - Christian B. Rosen
- Center for DNA Nanotechnology; Department of Chemistry and iNANO; Aarhus University; Gustav Wieds Vej14 8000 Aarhus C Denmark
| | - Michael R. Mortensen
- Center for DNA Nanotechnology; Department of Chemistry and iNANO; Aarhus University; Gustav Wieds Vej14 8000 Aarhus C Denmark
| | - Thomas Tørring
- Center for DNA Nanotechnology; Department of Chemistry and iNANO; Aarhus University; Gustav Wieds Vej14 8000 Aarhus C Denmark
| | - Kurt V. Gothelf
- Center for DNA Nanotechnology; Department of Chemistry and iNANO; Aarhus University; Gustav Wieds Vej14 8000 Aarhus C Denmark
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22
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Copper(II) complexes of three isomeric bis(tacn) ligands: Syntheses, structures and properties. Polyhedron 2016. [DOI: 10.1016/j.poly.2015.12.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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23
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Xu J, Ambrosini S, Tamahkar E, Rossi C, Haupt K, Tse Sum Bui B. Toward a Universal Method for Preparing Molecularly Imprinted Polymer Nanoparticles with Antibody-like Affinity for Proteins. Biomacromolecules 2015; 17:345-53. [DOI: 10.1021/acs.biomac.5b01454] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jingjing Xu
- Sorbonne Universités, Université de Technologie de Compiègne, CNRS Enzyme and Cell Engineering Laboratory, Rue Roger Couttolenc, CS 60319, 60203 Compiègne Cedex, France
| | - Serena Ambrosini
- Sorbonne Universités, Université de Technologie de Compiègne, CNRS Enzyme and Cell Engineering Laboratory, Rue Roger Couttolenc, CS 60319, 60203 Compiègne Cedex, France
| | - Emel Tamahkar
- Hitit University, Faculty
of Engineering, Department of Chemical Engineering, 19030 Çorum, Turkey
| | - Claire Rossi
- Sorbonne Universités, Université de Technologie de Compiègne, CNRS Enzyme and Cell Engineering Laboratory, Rue Roger Couttolenc, CS 60319, 60203 Compiègne Cedex, France
| | - Karsten Haupt
- Sorbonne Universités, Université de Technologie de Compiègne, CNRS Enzyme and Cell Engineering Laboratory, Rue Roger Couttolenc, CS 60319, 60203 Compiègne Cedex, France
| | - Bernadette Tse Sum Bui
- Sorbonne Universités, Université de Technologie de Compiègne, CNRS Enzyme and Cell Engineering Laboratory, Rue Roger Couttolenc, CS 60319, 60203 Compiègne Cedex, France
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24
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Facile synthesis of copper(II)-decorated magnetic particles for selective removal of hemoglobin from blood samples. J Chromatogr A 2015; 1424:18-26. [DOI: 10.1016/j.chroma.2015.11.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 10/09/2015] [Accepted: 11/02/2015] [Indexed: 11/21/2022]
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25
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26
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Sasaki S, Kobayashi M, Futagi Y, Ogura J, Yamaguchi H, Iseki K. Involvement of Histidine Residue His382 in pH Regulation of MCT4 Activity. PLoS One 2015; 10:e0122738. [PMID: 25919709 PMCID: PMC4412719 DOI: 10.1371/journal.pone.0122738] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 02/12/2015] [Indexed: 11/18/2022] Open
Abstract
Monocarboxylate transporter 4 (MCT4) is a pH-dependent bi-directional lactate transporter. Transport of lactate via MCT4 is increased by extracellular acidification. We investigated the critical histidine residue involved in pH regulation of MCT4 function. Transport of lactate via MCT4 was measured by using a Xenopus laevis oocyte expression system. MCT4-mediated lactate transport was inhibited by Zn2+ in a pH physiological condition but not in an acidic condition. The histidine modifier DEPC (diethyl pyrocarbonate) reduced MCT4 activity but did not completely inactivate MCT4. After treatment with DEPC, pH regulation of MCT4 function was completely knocked out. Inhibitory effects of DEPC were reversed by hydroxylamine and suppressed in the presence of excess lactate and Zn2+. Therefore, we performed an experiment in which the extracellular histidine residue was replaced with alanine. Consequently, the pH regulation of MCT4-H382A function was also knocked out. Our findings demonstrate that the histidine residue His382 in the extracellular loop of the transporter is essential for pH regulation of MCT4-mediated substrate transport activity.
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Affiliation(s)
- Shotaro Sasaki
- Laboratory of Clinical Pharmaceutics & Therapeutics, Division of Pharmasciences, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12-jo, Nishi-6-chome, Kita-ku, Sapporo 060–0812, Japan
| | - Masaki Kobayashi
- Laboratory of Clinical Pharmaceutics & Therapeutics, Division of Pharmasciences, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12-jo, Nishi-6-chome, Kita-ku, Sapporo 060–0812, Japan
| | - Yuya Futagi
- Laboratory of Clinical Pharmaceutics & Therapeutics, Division of Pharmasciences, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12-jo, Nishi-6-chome, Kita-ku, Sapporo 060–0812, Japan
| | - Jiro Ogura
- Laboratory of Clinical Pharmaceutics & Therapeutics, Division of Pharmasciences, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12-jo, Nishi-6-chome, Kita-ku, Sapporo 060–0812, Japan
| | - Hiroaki Yamaguchi
- Laboratory of Clinical Pharmaceutics & Therapeutics, Division of Pharmasciences, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12-jo, Nishi-6-chome, Kita-ku, Sapporo 060–0812, Japan
| | - Ken Iseki
- Laboratory of Clinical Pharmaceutics & Therapeutics, Division of Pharmasciences, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12-jo, Nishi-6-chome, Kita-ku, Sapporo 060–0812, Japan
- Department of Pharmacy, Hokkaido University Hospital, Sapporo 060–8648, Japan
- * E-mail:
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27
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Mooney JT, Fredericks DP, Christensen T, Bruun Schiødt C, Hearn MTW. N-terminal processing of affinity-tagged recombinant proteins purified by IMAC procedures. J Mol Recognit 2015; 28:401-12. [PMID: 25727088 DOI: 10.1002/jmr.2456] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 07/09/2014] [Accepted: 11/21/2014] [Indexed: 11/07/2022]
Abstract
The ability of a new class of metal binding tags to facilitate the purification of recombinant proteins, exemplified by the tagged glutathione S-transferase and human growth hormone, from Escherichia coli fermentation broths and lysates has been further investigated. These histidine-containing tags exhibit high affinity for borderline metal ions chelated to the immobilised ligand, 1,4,7-triazacyclononane (tacn). The use of this tag-tacn immobilised metal ion affinity chromatography (IMAC) system engenders high selectivity with regard to host cell protein removal and permits facile tag removal from the E. coli-expressed recombinant protein. In particular, these tags were specifically designed to enable their efficient removal by the dipeptidyl aminopeptidase 1 (DAP-1), thus capturing the advantages of high substrate specificity and rates of cleavage. MALDI-TOF MS analysis of the cleaved products from the DAP-1 digestion of the recombinant N-terminally tagged proteins confirmed the complete removal of the tag within 4-12 h under mild experimental conditions. Overall, this study demonstrates that the use of tags specifically designed to target tacn-based IMAC resins offers a comprehensive and flexible approach for the purification of E. coli-expressed recombinant proteins, where complete removal of the tag is an essential prerequisite for subsequent application of the purified native proteins in studies aimed at delineating the molecular and cellular basis of specific biological processes.
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Affiliation(s)
- Jane T Mooney
- Centre for Green Chemistry, School of Chemistry, Monash University, Clayton, Victoria, 3800, Australia
| | - Dale P Fredericks
- Centre for Green Chemistry, School of Chemistry, Monash University, Clayton, Victoria, 3800, Australia
| | | | | | - Milton T W Hearn
- Centre for Green Chemistry, School of Chemistry, Monash University, Clayton, Victoria, 3800, Australia
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Sivapragasam M, Abdullah N. RECOVERY OF CYCLODEXTRIN GLUCANOTRANSFERASE (CGTase) USING IMMOBILIZED METAL CHELATING AFFINITY CHROMATOGRAPHY. BRAZILIAN JOURNAL OF CHEMICAL ENGINEERING 2015. [DOI: 10.1590/0104-6632.20150321s00003124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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29
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Gu J, Codd R. The resolution of two clinical agents, bleomycin and desferrioxamine B, from a Streptomyces verticillus fermentation mixture using multi-dimensional immobilised metal ion affinity chromatography. RSC Adv 2015. [DOI: 10.1039/c4ra09315a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
A solution of bleomycin (BLM) and desferrioxamine B (DFOB) was resolved using two in-series columns containing BLM- or DFOB-tailored IMAC resin as a method with potential for accessing multiple clinical agents from fermentation.
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Affiliation(s)
- J. Gu
- School of Medical Sciences (Pharmacology) and Bosch Institute
- The University of Sydney
- Australia
| | - R. Codd
- School of Medical Sciences (Pharmacology) and Bosch Institute
- The University of Sydney
- Australia
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30
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Coghlan CJ, Campi EM, Forsyth CM, Jackson RW, Hearn MTW. Bi-Nuclear Metal Complexes of 2,6-Bis(1,4,7-triazacyclonon-1-yl-methylene)pyridine with Zinc(II), Copper(II), and Nickel(II). Aust J Chem 2015. [DOI: 10.1071/ch14618] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The coordination chemistry of 2,6-bis(1,4,7-triazacyclonon-1-ylmethyl)pyridine (Lpyx, 1) has been investigated and shown to yield bi-nuclear metal complexes in the presence of zinc(ii), copper(ii), or nickel(ii) ions. The reaction of (Lpyx)·7HCl (2) with Zn(NO3)2 gave the monomeric [Zn2(μ-Cl)2(Lpyx)(H2O)](ClO4)2 (3) in which the ligand encapsulates a Zn2(μ-Cl)2 moiety. Similar treatment of 2 with Cu(NO3)2 gave a bi-nuclear complex cation which exists as a 1 : 1 co-crystal {[Cu(Cl)(Lpyx)Cu(μ-Cl)(Cl)](BF4)(H2O)}2 and {[Cu(Cl)(Lpyx)Cu(μ-Cl)(H2O)](BF4)2(H2O)}2 (4) with two discrete CuII centres bridged by the Lpyx ligand and dimerised through an unsymmetrical Cu2(μ-Cl)2 interaction. Similarly, reaction of 2 with Ni(NO3)2 also gave a dimeric complex {[Ni(Cl)(μ-Cl)(Lpyx)Ni(NO3)(H2O)](PF6)}2 (5) containing two discrete NiII centres with dimerisation occurring through a symmetrical Ni2(μ-Cl)2 interaction. In all cases, the Lpyx ligand binding is unsymmetrical between the two metal centres being tridentate to one and tetradentate to the other through an additional coordination of the pyridyl linker.
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31
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Zheng J, Lin Z, Liu W, Wang L, Zhao S, Yang H, Zhang L. One-pot synthesis of CuFe 2O 4 magnetic nanocrystal clusters for highly specific separation of histidine-rich proteins. J Mater Chem B 2014; 2:6207-6214. [PMID: 32262138 DOI: 10.1039/c4tb00986j] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This work reports a facile ligand-free method for the rapid and highly specific separation of histidine (His)-rich proteins using CuFe2O4 magnetic nanocrystal clusters (MNCs). Monodispersed CuFe2O4 MNCs were synthesized via a simple and economical one-pot hydrothermal process. The resulting MNCs were characterized in detail. The measurements indicated that the MNCs exhibited good dispersion, high crystallinity, and superparamagnetic properties. Moreover, the obtained MNCs had a high saturation magnetization (45.1 emu g-1), which was sufficient to accomplish fast and efficient separation with an external magnetic field. The selectivity and binding capacity of CuFe2O4 MNCs were evaluated using a His-rich protein (bovine haemoglobin) and other proteins (bovine serum albumin, human serum albumin, myoglobin, lysozyme, cytochrome c and horseradish peroxidase) containing fewer surface-exposed His residues as model samples. The most distinct feature of the CuFe2O4 MNCs is the high haemoglobin binding capacity (4475 mg g-1) due to the coordination between copper(ii) ions and surface-exposed histidine resides of haemoglobin. In addition, the CuFe2O4 MNCs can be successfully employed to selectively bind and remove abundant haemoglobin from human blood samples. The good results demonstrate the potential of CuFe2O4 MNCs in the separation of His-rich proteins.
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Affiliation(s)
- Jiangnan Zheng
- Ministry of Education Key Laboratory of Analysis and Detection for Food Safety, Fujian Provincial Key Laboratory of Analysis and Detection Technology for Food Safety, College of Chemistry, Fuzhou University, Fuzhou, Fujian 350002, China.
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32
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Mooney JT, Fredericks D, Christensen T, Hearn MTW. Removal of cleavage slow points from affinity tags used in the IMAC purification of recombinant proteins. Biotechnol J 2014; 9:1023-32. [DOI: 10.1002/biot.201300546] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 05/07/2014] [Accepted: 06/26/2014] [Indexed: 11/06/2022]
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33
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Template-directed covalent conjugation of DNA to native antibodies, transferrin and other metal-binding proteins. Nat Chem 2014; 6:804-9. [PMID: 25143216 DOI: 10.1038/nchem.2003] [Citation(s) in RCA: 134] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 06/11/2014] [Indexed: 12/20/2022]
Abstract
DNA-protein conjugates are important in bioanalytical chemistry, molecular diagnostics and bionanotechnology, as the DNA provides a unique handle to identify, functionalize or otherwise manipulate proteins. To maintain protein activity, conjugation of a single DNA handle to a specific location on the protein is often needed. However, preparing such high-quality site-specific conjugates often requires genetically engineered proteins, which is a laborious and technically challenging approach. Here we demonstrate a simpler method to create site-selective DNA-protein conjugates. Using a guiding DNA strand modified with a metal-binding functionality, we directed a second DNA strand to the vicinity of a metal-binding site of His6-tagged or wild-type metal-binding proteins, such as serotransferrin, where it subsequently reacted with lysine residues at that site. This method, DNA-templated protein conjugation, facilitates the production of site-selective protein conjugates, and also conjugation to IgG1 antibodies via a histidine cluster in the constant domain.
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34
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Opazo CM, Greenough MA, Bush AI. Copper: from neurotransmission to neuroproteostasis. Front Aging Neurosci 2014; 6:143. [PMID: 25071552 PMCID: PMC4080678 DOI: 10.3389/fnagi.2014.00143] [Citation(s) in RCA: 111] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 06/16/2014] [Indexed: 01/23/2023] Open
Abstract
Copper is critical for the Central Nervous System (CNS) development and function. In particular, different studies have shown the effect of copper at brain synapses, where it inhibits Long Term Potentation (LTP) and receptor pharmacology. Paradoxically, according to recent studies copper is required for a normal LTP response. Copper is released at the synaptic cleft, where it blocks glutamate receptors, which explain its blocking effects on excitatory neurotransmission. Our results indicate that copper also enhances neurotransmission through the accumulation of PSD95 protein, which increase the levels of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors located at the plasma membrane of the post-synaptic density. Thus, our findings represent a novel mechanism for the action of copper, which may have implications for the neurophysiology and neuropathology of the CNS. These data indicate that synaptic configuration is sensitive to transient changes in transition metal homeostasis. Our results suggest that copper increases GluA1 subunit levels of the AMPA receptor through the anchorage of AMPA receptors to the plasma membrane as a result of PSD-95 accumulation. Here, we will review the role of copper on neurotransmission of CNS neurons. In addition, we will discuss the potential mechanisms by which copper could modulate neuronal proteostasis (“neuroproteostasis”) in the CNS with focus in the Ubiquitin Proteasome System (UPS), which is particularly relevant to neurological disorders such as Alzheimer’s disease (AD) where copper and protein dyshomeostasis may contribute to neurodegeneration. An understanding of these mechanisms may ultimately lead to the development of novel therapeutic approaches to control metal and synaptic alterations observed in AD patients.
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Affiliation(s)
- Carlos M Opazo
- Oxidation Biology Laboratory, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne Melbourne, VIC, Australia
| | - Mark A Greenough
- Oxidation Biology Laboratory, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne Melbourne, VIC, Australia
| | - Ashley I Bush
- Oxidation Biology Laboratory, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne Melbourne, VIC, Australia
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35
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Mayer MC, Kaden D, Schauenburg L, Hancock MA, Voigt P, Roeser D, Barucker C, Than ME, Schaefer M, Multhaup G. Novel zinc-binding site in the E2 domain regulates amyloid precursor-like protein 1 (APLP1) oligomerization. J Biol Chem 2014; 289:19019-30. [PMID: 24855651 DOI: 10.1074/jbc.m114.570382] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The amyloid precursor protein (APP) and the APP-like proteins 1 and 2 (APLP1 and APLP2) are a family of multidomain transmembrane proteins possessing homo- and heterotypic contact sites in their ectodomains. We previously reported that divalent metal ions dictate the conformation of the extracellular APP E2 domain (Dahms, S. O., Könnig, I., Roeser, D., Gührs, K.-H., Mayer, M. C., Kaden, D., Multhaup, G., and Than, M. E. (2012) J. Mol. Biol. 416, 438-452), but unresolved is the nature and functional importance of metal ion binding to APLP1 and APLP2. We found here that zinc ions bound to APP and APLP1 E2 domains and mediated their oligomerization, whereas the APLP2 E2 domain interacted more weakly with zinc possessing a less surface-exposed zinc-binding site, and stayed monomeric. Copper ions bound to E2 domains of all three proteins. Fluorescence resonance energy transfer (FRET) analyses examined the effect of metal ion binding to APP and APLPs in the cellular context in real time. Zinc ions specifically induced APP and APLP1 oligomerization and forced APLP1 into multimeric clusters at the plasma membrane consistent with zinc concentrations in the blood and brain. The observed effects were mediated by a novel zinc-binding site within the APLP1 E2 domain as APLP1 deletion mutants revealed. Based upon its cellular localization and its dominant response to zinc ions, APLP1 is mainly affected by extracellular zinc among the APP family proteins. We conclude that zinc binding and APP/APLP oligomerization are intimately linked, and we propose that this represents a novel mechanism for regulating APP/APLP protein function at the molecular level.
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Affiliation(s)
- Magnus C Mayer
- From the Institut für Chemie und Biochemie, Freie Universität Berlin, Thielallee 63, 14195 Berlin, Germany
| | - Daniela Kaden
- From the Institut für Chemie und Biochemie, Freie Universität Berlin, Thielallee 63, 14195 Berlin, Germany
| | - Linda Schauenburg
- From the Institut für Chemie und Biochemie, Freie Universität Berlin, Thielallee 63, 14195 Berlin, Germany
| | - Mark A Hancock
- the Department of Pharmacology and Therapeutics, McGill University Montreal, Montreal, Quebec H3G 1Y6, Canada
| | - Philipp Voigt
- the Molekulare Pharmakologie und Zellbiologie, Thielallee 67-73, Neurowissenschaftliches Forschungszentrum, Charité-Universitätsmedizin Berlin, 14195 Berlin, Germany
| | - Dirk Roeser
- the Leibniz Institute for Age Research, Protein Crystallography Group, Fritz Lipmann Institute, Beutenbergstrasse 11, 07745 Jena, Germany, and
| | - Christian Barucker
- the Department of Pharmacology and Therapeutics, McGill University Montreal, Montreal, Quebec H3G 1Y6, Canada
| | - Manuel E Than
- the Leibniz Institute for Age Research, Protein Crystallography Group, Fritz Lipmann Institute, Beutenbergstrasse 11, 07745 Jena, Germany, and
| | - Michael Schaefer
- the Rudolf-Boehm-Institut für Pharmakologie und Toxikologie, Medizinische Fakultät der Universität Leipzig, Härtelstrasse 16-18, 04107 Leipzig, Germany
| | - Gerhard Multhaup
- From the Institut für Chemie und Biochemie, Freie Universität Berlin, Thielallee 63, 14195 Berlin, Germany, the Department of Pharmacology and Therapeutics, McGill University Montreal, Montreal, Quebec H3G 1Y6, Canada,
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36
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Vega MA, Martín del Valle EM, Cerro RL, Galán MA. Productivity Model for Separation of Proteins Using Ceramic Monoliths As a Stationary Phase. Ind Eng Chem Res 2014. [DOI: 10.1021/ie500184s] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Milena A. Vega
- Department
of Chemical Engineering, University of Salamanca, P/Los Caídos S/N, 37008, Spain
| | | | - Ramón L. Cerro
- Department
of Chemical and Materials Engineering, University of Alabama in Huntsville, Huntsville, Alabama 35899, United States
| | - Miguel A. Galán
- Department
of Chemical Engineering, University of Salamanca, P/Los Caídos S/N, 37008, Spain
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37
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Mason L, Tribolet L, Simon A, von Gnielinski N, Nienaber L, Taylor P, Willis C, Jones MK, Sternberg PW, Gasser RB, Loukas A, Hofmann A. Probing the equatorial groove of the hookworm protein and vaccine candidate antigen, Na-ASP-2. Int J Biochem Cell Biol 2014; 50:146-55. [PMID: 24631931 DOI: 10.1016/j.biocel.2014.03.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 02/23/2014] [Accepted: 03/04/2014] [Indexed: 11/17/2022]
Abstract
Hookworm activation-associated secreted proteins can be structurally classified into at least three different groups. The hallmark feature of Group 1 activation-associated secreted proteins is a prominent equatorial groove, which is inferred to form a ligand binding site. Furthermore, a conserved tandem histidine motif is located in the centre of the groove and believed to provide or support a yet to be determined catalytic activity. Here, we report three-dimensional crystal structures of Na-ASP-2, an L3-secreted activation-associated secreted protein from the human hookworm Necator americanus, which demonstrate transition metal binding ability of the conserved tandem histidine motif. We further identified moderate phosphohydrolase activity of recombinant Na-ASP-2, which relates to the tandem histidine motif. By panning a random 12-mer peptide phage library, we identified a peptide with high similarity to the human calcium-activated potassium channel SK3, and confirm binding of the synthetic peptide to recombinant Na-ASP-2 by differential scanning fluorimetry. Potential binding modes of the peptide to Na-ASP-2 were studied by molecular dynamics simulations which clearly identify a preferred topology of the Na-ASP-2:SK3 peptide complex.
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Affiliation(s)
- Lyndel Mason
- Structural Chemistry Program, Eskitis Institute, Griffith University, Brisbane, Queensland, Australia
| | - Leon Tribolet
- Centre for Biodiscovery and Molecular Development of Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Queensland, Australia
| | - Anne Simon
- Université Lyon 1, Villeurbanne cedex, and Laboratoire Chimie et Biologie des Membranes et des Nanoobjets, Université Bordeaux, CBMN, UMR 5248, 33600 Pessac, France
| | - Natascha von Gnielinski
- Structural Chemistry Program, Eskitis Institute, Griffith University, Brisbane, Queensland, Australia
| | - Lisa Nienaber
- Structural Chemistry Program, Eskitis Institute, Griffith University, Brisbane, Queensland, Australia
| | - Paul Taylor
- Institute for Structural Biology, School of Biological Sciences, The University of Edinburgh, Scotland, UK
| | - Charlene Willis
- Structural Chemistry Program, Eskitis Institute, Griffith University, Brisbane, Queensland, Australia; School of Veterinary Science, The University of Queensland, Gatton, Queensland, Australia
| | - Malcolm K Jones
- School of Veterinary Science, The University of Queensland, Gatton, Queensland, Australia; Queensland Institute of Medical Research, Herston, Queensland, Australia
| | - Paul W Sternberg
- Biology Division, California Institute of Technology, Pasadena, CA, USA
| | - Robin B Gasser
- Faculty of Veterinary Science, The University of Melbourne, Parkville, Victoria, Australia
| | - Alex Loukas
- Centre for Biodiscovery and Molecular Development of Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Queensland, Australia.
| | - Andreas Hofmann
- Structural Chemistry Program, Eskitis Institute, Griffith University, Brisbane, Queensland, Australia; Faculty of Veterinary Science, The University of Melbourne, Parkville, Victoria, Australia.
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38
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Sun X, Chiu JF, He QY. Application of immobilized metal affinity chromatography in proteomics. Expert Rev Proteomics 2014; 2:649-57. [PMID: 16209645 DOI: 10.1586/14789450.2.5.649] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
It has been proved that the progress of proteomics is mostly determined by the development of advanced and sensitive protein separation technologies. Immobilized metal affinity chromatography (IMAC) is a powerful protein fractionation method used to enrich metal-associated proteins and peptides. In proteomics, IMAC has been widely employed as a prefractionation method to increase the resolution in protein separation. The combination of IMAC with other protein analytical technologies has been successfully utilized to characterize metalloproteome and post-translational modifications. In the near future, newly developed IMAC integrated with other proteomic methods will greatly contribute to the revolution of expression, cell-mapping and structural proteomics.
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Affiliation(s)
- Xuesong Sun
- Department of Chemistry, University of Hong Kong, Pokfulam, Hong Kong.
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40
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Purification and covalent immobilization of benzaldehyde lyase with heterofunctional chelate-epoxy modified magnetic nanoparticles and its carboligation reactivity. ACTA ACUST UNITED AC 2013. [DOI: 10.1016/j.molcatb.2013.05.023] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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41
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Wijeratne S, Bruening ML, Baker GL. Layer-by-layer assembly of thick, Cu(2+)-chelating films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:12720-9. [PMID: 24044576 PMCID: PMC3873220 DOI: 10.1021/la402633x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Layer-by-layer adsorption of protonated poly(allylamine) (PAH) and deprotonated poly(N,N-dicarboxymethylallylamine) (PDCMAA) yields thick films with a high density of iminodiacetic acid (IDA) ligands that bind metal ions. When film deposition occurs at pH 3.0, PAH/PDCMAA bilayer thicknesses reach 200 nm, and Cu(2+) binding capacities are ~2.5 mmol per cm(3) of film. (PAH/PDCMAA)10 films deposited at pH 3.0 are 4-8-fold thicker than films formed at pH 5.0, 7.0, or 9.0, presumably because of the low charge density on PDCMAA chains at pH 3.0. However, with normalization to film thickness, all films bind similar amounts of Cu(2+) from pH 4.1 solutions of CuSO4. In micrometer-thick films, equilibration of binding sites with Cu(2+) requires ~4 h due to a low Cu(2+) diffusion coefficient (~2.6 × 10(-12) cm(2)/s). Sorption isotherms determined at several temperatures show that Cu(2+) binding is endothermic with a positive entropy (binding constants increase with increasing temperature), presumably because metal-ion complexation involves displacement of both a proton from IDA and water molecules from Cu(2+). (PAH/PDCMAA)10 films retain their binding capacity over four absorption/elution cycles and may prove useful in metal-ion scavenging, catalysis, and protein binding.
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Affiliation(s)
- Salinda Wijeratne
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
| | - Merlin L. Bruening
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
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Selective Introduction of Sulfhydryl Groups into Recombinant Proteins for Study of Protein–Protein Interactions. Chromatographia 2013. [DOI: 10.1007/s10337-013-2463-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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43
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Carboligation reactivity of benzaldehyde lyase (BAL, EC 4.1.2.38) covalently attached to magnetic nanoparticles. ACTA ACUST UNITED AC 2013. [DOI: 10.1016/j.tetasy.2013.01.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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44
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Cheung RCF, Wong JH, Ng TB. Immobilized metal ion affinity chromatography: a review on its applications. Appl Microbiol Biotechnol 2012; 96:1411-20. [PMID: 23099912 DOI: 10.1007/s00253-012-4507-0] [Citation(s) in RCA: 156] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Revised: 10/10/2012] [Accepted: 10/10/2012] [Indexed: 01/14/2023]
Abstract
After 35 years of development, immobilized metal ion affinity chromatography (IMAC) has evolved into a popular protein purification technique. This review starts with a discussion of its mechanism and advantages. It continues with its applications which include the purification of histidine-tagged proteins, natural metal-binding proteins, and antibodies. IMAC used in conjunction with mass spectroscopy for phosphoprotein fractionation and proteomics is also covered. Finally, this review addresses the developments, limitations, and considerations of IMAC in the biopharmaceutical industry.
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Affiliation(s)
- Randy Chi Fai Cheung
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, China
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Joshi S, Ghosh I, Pokhrel S, Mädler L, Nau WM. Interactions of amino acids and polypeptides with metal oxide nanoparticles probed by fluorescent indicator adsorption and displacement. ACS NANO 2012; 6:5668-5679. [PMID: 22591378 DOI: 10.1021/nn301669t] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The adsorption of polypeptides containing an N-terminal tryptophan (Trp) residue attached to a hexa-backbone of alanine, serine, lysine, histidine, and aspartate was investigated by monitoring the fluorescence response of the Trp chromophore upon titration with metal oxide nanoparticles (MOx-NPs: CuO, Co(3)O(4), TiO(2), MgO, and CeO(2)). After correction for light-scattering effects, a strong static fluorescence quenching was observed upon addition of CuO and Co(3)O(4) to the peptides. The interaction of MOx-NPs with the peptides was assigned to an adsorption of the peptide backbone on the nanoparticle surface. The method was refined using a derivatized amino acid, 5-fluoro-Trp (5F-Trp), which resulted in a stronger fluorescence response. The use of the fluorescent amino acid labels allowed the direct assessment of the adsorption propensities of Trp-containing peptides in dependence on the backbone, which was verified by zeta-potential measurements. Moreover, upon addition of different analytes to nanoparticles with preadsorbed Trp-containing polypeptides, adsorption propensities of the analytes were assessed by an indicator displacement strategy; that is, addition of increasing amounts of analyte resulted in a continuous fluorescence enhancement/recovery. This method afforded adsorption propensities for several analytes. The relative binding constants for the MOx-NPs, obtained from the competitive titrations, varied by more than 6 orders of magnitude for CuO (5F-TrpHis(6)-NH(2) > TrpAsp(6)-NH(2), TrpSer(6)-NH(2) > TrpLys(6)-NH(2), Trp, 5F-Trp > TrpAla(6)-NH(2)) but only 4 for Co(3)O(4) (TrpHis(6)-NH(2), TrpAsp(6)-NH(2) ≫ TrpLys(6)-NH(2), TrpAla(6)-NH(2), TrpSer(6)-NH(2), Trp, 5F-Trp). The study reveals that MOx-NPs adsorb biomolecular analytes with high selectivity, which has immediate implications for their applications in protein purification, drug delivery, and, potentially, for the assessment of their toxicology.
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Affiliation(s)
- Sweccha Joshi
- School of Engineering and Science, Jacobs University Bremen, Campus Ring 1, D-28759 Bremen, Germany
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46
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Altintaş EB, Yavuz H, Say R, Denizli A. Methacryloylamidoglutamic acid having porous magnetic beads as a stationary phase in metal chelate affinity chromatography. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2012; 17:213-26. [PMID: 16411610 DOI: 10.1163/156856206774879045] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We have prepared a novel magnetic metal-chelate adsorbent utilizing methacryloylamidoglutamic acid (MAGA) as a metal-chelating ligand. MAGA was synthesized by using methacryloyl chloride and L-glutamic acid dihydrochloride. Magnetic beads with an average diameter of 50-100 microm were produced by suspension polymerization of 2-hydroxyethyl methacrylate (HEMA) and MAGA in the presence of Fe3O4 particles carried out in an aqueous dispersion medium. Magnetic beads were charged with the Cu2+ ions directly via MAGA for the adsorption of cytochrome c (cyt c) from aqueous solutions. The maximum cyt c adsorption capacity of the Cu2+-chelated beads (0.86 mmol/g Cu2+ loading) was found to be 37 mg/g at pH 8.0 in phosphate buffer. Cyt c adsorption on the poly(HEMA-MAGA) beads was 15.4 mg/g. Cu2+ charging increased the cyt c adsorption significantly (37 mg/g). Cyt c adsorption decreased with increasing temperature. Cyt c molecules could be adsorbed and desorbed five times with these adsorbents without noticeable loss in their cyt c adsorption capacity. The resulting magnetic chelator beads posses excellent long term storage stability.
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Affiliation(s)
- Evrim Banu Altintaş
- Department of Chemistry, Biochemistry Division, Hacettepe University, Ankara, Turkey
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47
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Kang X, Li X, Hewitt WM, Zuckerman NB, Konopelski JP, Chen S. Manipulation of Intraparticle Charge Delocalization by Selective Complexation of Transition-Metal Ions with Histidine Moieties. Anal Chem 2012; 84:2025-30. [DOI: 10.1021/ac203218h] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xiongwu Kang
- Department
of Chemistry and Biochemistry, University of California, 1156 High Street, Santa Cruz, California
95064, United States
| | - Xiang Li
- Department
of Chemistry and Biochemistry, University of California, 1156 High Street, Santa Cruz, California
95064, United States
| | - William M. Hewitt
- Department
of Chemistry and Biochemistry, University of California, 1156 High Street, Santa Cruz, California
95064, United States
| | - Nathaniel B. Zuckerman
- Department
of Chemistry and Biochemistry, University of California, 1156 High Street, Santa Cruz, California
95064, United States
| | - Joseph P. Konopelski
- Department
of Chemistry and Biochemistry, University of California, 1156 High Street, Santa Cruz, California
95064, United States
| | - Shaowei Chen
- Department
of Chemistry and Biochemistry, University of California, 1156 High Street, Santa Cruz, California
95064, United States
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48
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James SA, Volitakis I, Adlard PA, Duce JA, Masters CL, Cherny RA, Bush AI. Elevated labile Cu is associated with oxidative pathology in Alzheimer disease. Free Radic Biol Med 2012; 52:298-302. [PMID: 22080049 DOI: 10.1016/j.freeradbiomed.2011.10.446] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2011] [Revised: 09/20/2011] [Accepted: 10/06/2011] [Indexed: 11/28/2022]
Abstract
Oxidative stress is implicated in Alzheimer disease (AD) pathogenesis, for which evidence indicates that radical species are generated by the redox-active biometal Cu. The contribution of labile Cu to the oxidative stress observed in AD has not been evaluated. The Cu content of postmortem cortical tissue from nondemented elderly controls and AD cases was measured using inductively coupled plasma mass spectroscopy, and the proportion of labile Cu was assessed using the Cu-phenanthroline assay. Further, the capacity of the tissue to stabilize Cu(2+) was evaluated using immobilized metal-affinity chromatography, and the level of tissue oxidative damage was determined by the presence of thiobarbituric acid-reactive compounds. We identified elevated levels of exchangeable Cu(2+), which were correlated with tissue oxidative damage; additionally, we noted an increased capacity of AD cortical tissue samples to bind Cu(2+). This deranged Cu homeostasis reflects the homeostatic breakdown of Cu observed in AD and supports biometal metabolism as a therapeutic target.
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Affiliation(s)
- Simon A James
- The Mental Health Research Institute, The University of Melbourne, Melbourne, VIC 3010, Australia
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49
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Zhang A, Zhang C, Warikoo V, Forstrom J, Riske F. A modified IMAC method for the capture of target protein from mammalian cell culture harvest containing metal chelating species. Biotechnol Bioeng 2011; 109:747-53. [PMID: 22012836 DOI: 10.1002/bit.24353] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Revised: 10/07/2011] [Accepted: 10/14/2011] [Indexed: 11/09/2022]
Abstract
Although immobilized metal affinity chromatography (IMAC) offers high capacity and protein selectivity it is not typically used commercially for the capture of native proteins from mammalian cell culture harvest. This is due mainly to the potential for low target recovery due to the presence of strong metal ion chelating species in the harvest that compete for the metal immobilized on the resin. To address this issue a buffer exchange step, such as tangential flow filtration (TFF), is added after harvest clarification and prior to IMAC to remove the interfering harvest components. The addition of a TFF step adds process time and cost and reduces target protein recovery. The elimination of the TFF might make IMAC competitive with other orthogonal methods of protein capture. In this study, we developed a modified IMAC method to allow the direct loading of clarified mammalian harvest without prior buffer exchange (direct IMAC). Although the target enzyme recovery was lower than that from standard IMAC the elimination of the buffer exchange step resulted in a 19% increase in overall enzyme recovery. The target enzyme capacity in direct IMAC was higher, in our experience, than the capacity of hydrophobic interaction (HIC) and ion-exchange (IEX) for protein capture. An economic evaluation of using direct IMAC as a capture step in manufacturing is also discussed.
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Affiliation(s)
- Aming Zhang
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia, USA
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50
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Eldin MSM, Rahman SA, Fawal GFE. Preparation and characterization of grafted cellophane membranes for affinity separation of His-tag Chitinase. ADVANCES IN POLYMER TECHNOLOGY 2011. [DOI: 10.1002/adv.20216] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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