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Gao F, Liu G, Qiao Y, Dong X, Liu L. Streptavidin-Conjugated DNA for the Boronate Affinity-Based Detection of Poly(ADP-Ribose) Polymerase-1 with Improved Sensitivity. Biosensors (Basel) 2023; 13:723. [PMID: 37504121 PMCID: PMC10377026 DOI: 10.3390/bios13070723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 06/24/2023] [Accepted: 07/04/2023] [Indexed: 07/29/2023]
Abstract
This work reports the development of a fluorescence method for the detection of poly(ADP-ribose) polymerase-1 (PARP1), in which a phenylboronic acid-modified fluorescein isothiocyanate dye (FITC-PBA) was used to recognize the formed poly(ADP-ribose) (PAR) polymer. The detection system was designed by conjugating recombinant streptavidin (rSA) with PARP1-specific double-stranded DNA (dsDNA) through streptavidin-biotin interaction. Capture of PARP1 via rSA-biotin-dsDNA allowed for the poly-ADP-ribosylation (PARylation) of both rSA and PARP1 in a homogeneous solution. The resulting rSA-biotin-dsDNA/PAR conjugates were then captured and separated via the commercialized nitrilotriacetic acid-nickel ion-modified magnetic bead (MB-NTA-Ni) through the interaction between NTA-Ni on MB surface and oligohistidine (His6) tag in rSA. The PAR polymer could capture the dye of FITC-PBA through the borate ester interaction between the boronic acid moiety in PBA and the cis-diol group in ribose, thus causing a decrease in fluorescence signal. The PARylation of streptavidin and the influence of steric hindrance on PARylation efficiency were confirmed using reasonable detection strategies. The method showed a wide linear range (0.01~20 U) and a low detection limit (0.01 U). This work should be valuable for the development of novel biosensors for the detection of poly(ADP-ribose) polymerases and diol-containing species.
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Affiliation(s)
- Fengli Gao
- College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang 455000, China
| | - Gang Liu
- College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang 455000, China
- College of Chemistry and Chemical Engineering, Henan University of Technology, Zhengzhou 450001, China
| | - Yishu Qiao
- College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang 455000, China
| | - Xiuwen Dong
- College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang 455000, China
| | - Lin Liu
- College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang 455000, China
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2
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Chen HY, Lin YF. DFT study on the catalytic decomposition of hydrogen peroxide by iron complexes of nitrilotriacetate. J Comput Chem 2023. [PMID: 37337982 DOI: 10.1002/jcc.27179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 05/17/2023] [Accepted: 06/11/2023] [Indexed: 06/21/2023]
Abstract
The Fenton system in the presence of nitrilotriacetate (NTA) ligand is studied by DFT approach. The calculations show that complexation of Fe(II) with NTA significantly facilitates the H2 O2 activation. The ferric-hydroperoxo intermediate NTAFe(III)OOH predominantly decays via the disproportionation into NTAFe(II)OH2 and NTAFe(IV)O involving the formation of a μ-1,2-hydroperoxo-bridged biferric intermediate. In this mechanism, the bridged hydroperoxo is reduced by hydroperoxo ligand rather than by Fe(III). On the one hand, the NTAFe(III)OOH is sluggish to undergo hydrogen abstraction; on the other hand, it is a good nucleophile that may perform aldehyde deformylation. The present calculations suggest that both ˙OH and Fe(IV)O are generated in the NTA-assisted Fenton system. However, the polycarboxylate ligand provides a favorable environment for H2 O2 to accumulate around iron ion through hydrogen bonding. This promotes the quenching of Fe(IV)O by H2 O2 , rationalizing why the Fe(IV)O species is hardly detected in the NTA-assisted Fenton system.
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Affiliation(s)
- Hsing-Yin Chen
- Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Yu-Fen Lin
- Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung, Taiwan
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3
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Zhu L, Chang Y, Li Y, Qiao M, Liu L. Biosensors Based on the Binding Events of Nitrilotriacetic Acid-Metal Complexes. Biosensors (Basel) 2023; 13:bios13050507. [PMID: 37232868 DOI: 10.3390/bios13050507] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Revised: 04/21/2023] [Accepted: 04/24/2023] [Indexed: 05/27/2023]
Abstract
Molecular immobilization and recognition are two key events for the development of biosensors. The general ways for the immobilization and recognition of biomolecules include covalent coupling reactions and non-covalent interactions of antigen-antibody, aptamer-target, glycan-lectin, avidin-biotin and boronic acid-diol. Tetradentate nitrilotriacetic acid (NTA) is one of the most common commercial ligands for chelating metal ions. The NTA-metal complexes show high and specific affinity toward hexahistidine tags. Such metal complexes have been widely utilized in protein separation and immobilization for diagnostic applications since most of commercialized proteins have been integrated with hexahistidine tags by synthetic or recombinant techniques. This review focused on the development of biosensors with NTA-metal complexes as the binding units, mainly including surface plasmon resonance, electrochemistry, fluorescence, colorimetry, surface-enhanced Raman scattering spectroscopy, chemiluminescence and so on.
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Affiliation(s)
- Lin Zhu
- College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang 455000, China
| | - Yong Chang
- College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang 455000, China
| | - Yingying Li
- College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang 455000, China
| | - Mingyi Qiao
- College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang 455000, China
| | - Lin Liu
- College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang 455000, China
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Gong Y, Shen J, Shen L, Zhao S, Wu Y, Zhou Y, Cui L, Kang J, Chen Z. Whose Oxygen Atom Is Transferred to the Products? A Case Study of Peracetic Acid Activation via Complexed Mn II for Organic Contaminant Degradation. Environ Sci Technol 2023; 57:6723-6732. [PMID: 37043741 DOI: 10.1021/acs.est.2c09611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Identifying reactive species in advanced oxidation process (AOP) is an essential and intriguing topic that is also challenging and requires continuous efforts. In this study, we exploited a novel AOP technology involving peracetic acid (PAA) activation mediated by a MnII-nitrilotriacetic acid (NTA) complex, which outperformed iron- and cobalt-based PAA activation processes for rapidly degrading phenolic and aniline contaminants from water. The proposed MnII/NTA/PAA system exhibited non-radical oxidation features and could stoichiometrically oxidize sulfoxide probes to the corresponding sulfone products. More importantly, we traced the origin of O atoms from the sulfone products by 18O isotope-tracing experiments and found that PAA was the only oxygen-donor, which is different from the oxidation process mediated by high-valence manganese-oxo intermediates. According to the results of theoretical calculations, we proposed that NTA could tune the coordination circumstance of the MnII center to elongate the O-O bond of the complexed PAA. Additionally, the NTA-MnII-PAA* molecular cluster presented a lower energy gap than the MnII-PAA complex, indicating that the MnII-peroxy complex was more reactive in the presence of NTA. Thus, the NTA-MnII-PAA* complex exhibited a stronger oxidation potential than PAA, which could rapidly oxidize organic contaminants from water. Further, we generalized our findings to the CoII/PAA oxidation process and highlighted that the CoII-PAA* complex might be the overlooked reactive cobalt species. The significance of this work lies in discovering that sometimes the metal-peroxy complex could directly oxidize the contaminants without the further generation of high-valence metal-oxo intermediates and/or radical species through interspecies oxygen and/or electron transfer.
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Affiliation(s)
- Yingxu Gong
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150090, China
| | - Jimin Shen
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150090, China
| | - Linlu Shen
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150090, China
| | - Shengxin Zhao
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150090, China
| | - Yining Wu
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150090, China
| | - Yanchi Zhou
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150090, China
| | - Lei Cui
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150090, China
| | - Jing Kang
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150090, China
| | - Zhonglin Chen
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150090, China
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5
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Ma X, Lv Y, Liu P, Hao Y, Xia N. Switch-on Fluorescence Analysis of Protease Activity with the Assistance of a Nickel Ion- Nitrilotriacetic Acid-Conjugated Magnetic Nanoparticle. Molecules 2023; 28:molecules28083426. [PMID: 37110659 PMCID: PMC10144723 DOI: 10.3390/molecules28083426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 04/07/2023] [Accepted: 04/10/2023] [Indexed: 04/29/2023] Open
Abstract
Heterogeneous protease biosensors show high sensitivity and selectivity but usually require the immobilization of peptide substrates on a solid interface. Such methods exhibit the disadvantages of complex immobilization steps and low enzymatic efficiency induced by steric hindrance. In this work, we proposed an immobilization-free strategy for protease detection with high simplicity, sensitivity and selectivity. Specifically, a single-labeled peptide with oligohistidine-tag (His-tag) was designed as the protease substrate, which can be captured by a nickel ion-nitrilotriacetic acid (Ni-NTA)-conjugated magnetic nanoparticle (MNP) through the coordination interaction between His-tag and Ni-NTA. When the peptide was digested by protease in a homogeneous solution, the signal-labeled segment was released from the substrate. The unreacted peptide substrates could be removed by Ni-NTA-MNP, and the released segments remained in solution to emit strong fluorescence. The method was used to determine protease of caspase-3 with a low detection limit (4 pg/mL). By changing the peptide sequence and signal reporters, the proposal could be used to develop novel homogeneous biosensors for the detection of other proteases.
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Affiliation(s)
- Xiaohua Ma
- Henan Key Laboratory of Biomolecular Recognition and Sensing, Shangqiu Normal University, Shangqiu 476000, China
| | - Yingxin Lv
- College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang 455000, China
| | - Panpan Liu
- College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang 455000, China
| | - Yuanqiang Hao
- Henan Key Laboratory of Biomolecular Recognition and Sensing, Shangqiu Normal University, Shangqiu 476000, China
| | - Ning Xia
- College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang 455000, China
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6
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Li Z, Munro K, Narouz MR, Lau A, Hao H, Crudden CM, Horton JH. Self-Assembled N-Heterocyclic Carbene-Based Carboxymethylated Dextran Monolayers on Gold as a Tunable Platform for Designing Affinity-Capture Biosensor Surfaces. ACS Appl Mater Interfaces 2018; 10:17560-17570. [PMID: 29741868 DOI: 10.1021/acsami.8b02595] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Sensor surfaces play a predominant role in the development of optical biosensor technologies for the analysis of biomolecular interactions. Thiol-based self-assembled monolayers (SAMs) on gold have been widely used as linker layers for sensor surfaces. However, the degradation of the thiol-gold bond can limit the performance and durability of such surfaces, directly impacting their performance and cost-effectiveness. To this end, a new family of materials based on N-heterocyclic carbenes (NHCs) has emerged as an alternative for surface modification, capable of self-assembling onto a gold surface with higher affinity and superior stability as compared to the thiol-based systems. Here we demonstrate three applications of NHC SAMs supporting a dextran layer as a tunable platform for developing various affinity-capture biosensor surfaces. We describe the development and testing of NHC-based dextran biosensor surfaces modified with each of streptavidin, nitrilotriacetic acid, and recombinant Protein A. These affinity-capture sensor surfaces enable oriented binding of ligands for optimal performance in biomolecular assays. Together, the intrinsic high stability and flexible design of the NHC biosensing platforms show great promise and open up exciting possibilities for future biosensing applications.
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Affiliation(s)
| | | | | | | | - Hongxia Hao
- Collaborative Innovation Center of Judicial Civilization and Key Laboratory of Evidence Science , China University of Political Science and Law , Beijing 100088 , China
| | - Cathleen M Crudden
- Institute for Transformative Bio-Molecules (ITbM-WPI) , Nagoya University , Chikusa, Nagoya 464-8602 , Japan
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Hatty CR, Le Brun AP, Lake V, Clifton LA, Liu GJ, James M, Banati RB. Investigating the interactions of the 18kDa translocator protein and its ligand PK11195 in planar lipid bilayers. Biochim Biophys Acta 2013; 1838:1019-30. [PMID: 24374318 DOI: 10.1016/j.bbamem.2013.12.013] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 12/16/2013] [Accepted: 12/18/2013] [Indexed: 12/20/2022]
Abstract
The functional effects of a drug ligand may be due not only to an interaction with its membrane protein target, but also with the surrounding lipid membrane. We have investigated the interaction of a drug ligand, PK11195, with its primary protein target, the integral membrane 18kDa translocator protein (TSPO), and model membranes using Langmuir monolayers, quartz crystal microbalance with dissipation monitoring (QCM-D) and neutron reflectometry (NR). We found that PK11195 is incorporated into lipid monolayers and lipid bilayers, causing a decrease in lipid area/molecule and an increase in lipid bilayer rigidity. NR revealed that PK11195 is incorporated into the lipid chain region at a volume fraction of ~10%. We reconstituted isolated mouse TSPO into a lipid bilayer and studied its interaction with PK11195 using QCM-D, which revealed a larger than expected frequency response and indicated a possible conformational change of the protein. NR measurements revealed a TSPO surface coverage of 23% when immobilised to a modified surface via its polyhistidine tag, and a thickness of 51Å for the TSPO layer. These techniques allowed us to probe both the interaction of TSPO with PK11195, and PK11195 with model membranes. It is possible that previously reported TSPO-independent effects of PK11195 are due to incorporation into the lipid bilayer and alteration of its physical properties. There are also implications for the variable binding profiles observed for TSPO ligands, as drug-membrane interactions may contribute to the apparent affinity of TSPO ligands.
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Affiliation(s)
- Claire R Hatty
- Medical Imaging & Radiation Sciences Faculty Research Group, Faculty of Health Sciences, The University of Sydney, c/o Brain & Mind Research Institute, 94 Mallett Street, Camperdown, NSW 2050, Australia
| | - Anton P Le Brun
- Bragg Institute, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, NSW 2234, Australia
| | - Vanessa Lake
- Bragg Institute, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, NSW 2234, Australia
| | - Luke A Clifton
- ISIS Pulsed Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Didcot OX11 0QX, UK
| | - Guo Jun Liu
- Medical Imaging & Radiation Sciences Faculty Research Group, Faculty of Health Sciences, The University of Sydney, c/o Brain & Mind Research Institute, 94 Mallett Street, Camperdown, NSW 2050, Australia; Life Sciences, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, NSW 2234, Australia
| | - Michael James
- Bragg Institute, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, NSW 2234, Australia; School of Chemistry, University of New South Wales, Kensington NSW 2052, Australia
| | - Richard B Banati
- Medical Imaging & Radiation Sciences Faculty Research Group, Faculty of Health Sciences, The University of Sydney, c/o Brain & Mind Research Institute, 94 Mallett Street, Camperdown, NSW 2050, Australia; Life Sciences, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, NSW 2234, Australia.
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8
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Teunissen EA, de Raad M, Mastrobattista E. Production and biomedical applications of virus-like particles derived from polyomaviruses. J Control Release 2013; 172:305-321. [PMID: 23999392 DOI: 10.1016/j.jconrel.2013.08.026] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 08/18/2013] [Accepted: 08/20/2013] [Indexed: 10/26/2022]
Abstract
Virus-like particles (VLPs), aggregates of capsid proteins devoid of viral genetic material, show great promise in the fields of vaccine development and gene therapy. These particles spontaneously self-assemble after heterologous expression of viral structural proteins. This review will focus on the use of virus-like particles derived from polyomavirus capsid proteins. Since their first recombinant production 27 years ago these particles have been investigated for a myriad of biomedical applications. These virus-like particles are safe, easy to produce, can be loaded with a broad range of diverse cargoes and can be tailored for specific delivery or epitope presentation. We will highlight the structural characteristics of polyomavirus-derived VLPs and give an overview of their applications in diagnostics, vaccine development and gene delivery.
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Affiliation(s)
- Erik A Teunissen
- Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, University of Utrecht, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
| | - Markus de Raad
- Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, University of Utrecht, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
| | - Enrico Mastrobattista
- Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, University of Utrecht, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.
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Park E, Lee JW, Yoo HM, Ha BH, An JY, Jeon YJ, Seol JH, Eom SH, Chung CH. Structural alteration in the pore motif of the bacterial 20S proteasome homolog HslV leads to uncontrolled protein degradation. J Mol Biol 2013; 425:2940-54. [PMID: 23707406 DOI: 10.1016/j.jmb.2013.05.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 04/29/2013] [Accepted: 05/15/2013] [Indexed: 11/27/2022]
Abstract
In all cells, ATP-dependent proteases play central roles in the controlled degradation of short-lived regulatory or misfolded proteins. A hallmark of these enzymes is that proteolytic active sites are sequestered within a compartmentalized space, which is accessible to substrates only when they are fed into the cavity by protein-unfolding ATPases. HslVU is a prototype of such enzymes, consisting of the hexameric HslU ATPase and the dodecameric HslV protease. HslV forms a barrel-shaped proteolytic chamber with two constricted axial pores. Here, we report that structural alterations of HslV's pore motif dramatically affect the proteolytic activities of both HslV and HslVU complexes. Mutations of a conserved pore residue in HslV (Leu88 to Ala, Gly, or Ser) led to a tighter binding between HslV and HslU and a dramatic stimulation of both the proteolytic and ATPase activities. Furthermore, the HslV mutants alone showed a marked increase of basal hydrolytic activities toward small peptides and unstructured proteins. A synthetic peptide of the HslU C-terminal tail further stimulated the proteolytic activities of these mutants, even allowing degradation of certain folded proteins in the absence of HslU. Moreover, expression of the L88A mutant in Escherichia coli inhibited cell growth, suggesting that HslV pore mutations dysregulate the protease through relaxing the pore constriction, which normally prevents essential cellular proteins from random degradation. Consistent with these observations, an X-ray crystal structure shows that the pore loop of L88A-HslV is largely disordered. Collectively, these results suggest that substrate degradation by HslV is controlled by gating of its pores.
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Affiliation(s)
- Eunyong Park
- School of Biological Sciences, Seoul National University, Seoul 151-742, South Korea
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10
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Locatelli-Hoops SC, Gorshkova I, Gawrisch K, Yeliseev AA. Expression, surface immobilization, and characterization of functional recombinant cannabinoid receptor CB2. Biochim Biophys Acta 2013; 1834:2045-56. [PMID: 23777860 DOI: 10.1016/j.bbapap.2013.06.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 06/05/2013] [Accepted: 06/07/2013] [Indexed: 11/23/2022]
Abstract
Human peripheral cannabinoid receptor CB2, a G protein-coupled receptor (GPCR) involved in regulation of immune response has become an important target for pharmaceutical drug development. Structural and functional studies on CB2 may benefit from immobilization of the purified and functional receptor onto a suitable surface at a controlled density and, preferably in a uniform orientation. The goal of this project was to develop a generic strategy for preparation of functional recombinant CB2 and immobilization at solid interfaces. Expression of CB2 as a fusion with Rho-tag (peptide composed of the last nine amino acids of rhodopsin) in E. coli was evaluated in terms of protein levels, accessibility of the tag, and activity of the receptor. The structural integrity of CB2 was tested by ligand binding to the receptor solubilized in detergent micelles, captured on tag-specific monoclonal 1D4 antibody-coated resin. Highly pure and functional CB2 was obtained by sequential chromatography on a 1D4- and Ni-NTA-resin and its affinity to the 1D4 antibody characterized by surface plasmon resonance (SPR). Either the purified receptor or fusion CB2 from the crude cell extract was captured onto a 1D4-coated CM4 chip (Biacore) in a quantitative fashion at uniform orientation as demonstrated by the SPR signal. Furthermore, the accessibility of the extracellular surface of immobilized CB2 and the affinity of interaction with a novel monoclonal antibody NAA-1 was studied by SPR. In summary, we present an integral strategy for purification, surface immobilization, ligand- and antibody binding studies of functional cannabinoid receptor CB2.
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Yao P, Hao L, Wang F, Chen X, Yan Y, Guo X, Xu B. Molecular cloning, expression and antioxidant characterisation of a typical thioredoxin gene (AccTrx2) in Apis cerana cerana. Gene 2013; 527:33-41. [PMID: 23747404 DOI: 10.1016/j.gene.2013.05.062] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2013] [Revised: 05/29/2013] [Accepted: 05/31/2013] [Indexed: 11/26/2022]
Abstract
Thioredoxins (Trxs) are a family of small, highly conserved and ubiquitous proteins that are involved in protecting organisms against toxic reactive oxygen species (ROS). In this study, a typical thioredoxin 2 gene was isolated from Apis cerana cerana, AccTrx2. The full-length cDNA sequence of AccTrx2 was composed of 407 bp containing a 318 bp open reading frame (ORF) that encodes a predicted protein of 105 amino acids, 11.974 kDa and an isoelectric point of 4.45. Expression profile of AccTrx2 as determined by a quantitative real-time PCR (qRT-PCR) analysis was higher in brain than in other tissues, with its highest transcript occurring on the 15day post-emergence adult and upregulated by such abiotic stresses as 4 °C, 16 °C, 25 °C, H2O2, cyhalothrin, acaricide, paraquat, phoxime and mercury (HgCl2) treatments. However, AccTrx2 was slightly repressed when exposed to 42 °C treatment. Characterisation of the recombinant protein showed that the purified AccTrx2 had insulin disulfide reductase activity and could protect DNA from ROS damage. These results indicate that AccTrx2 functions as an antioxidant that plays an important role in response to oxidative stress.
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Affiliation(s)
- Pengbo Yao
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, PR China
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12
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Wegner SV, Spatz JP. Cobalt(III) as a stable and inert mediator ion between NTA and His6-tagged proteins. Angew Chem Int Ed Engl 2013; 52:7593-6. [PMID: 23740821 PMCID: PMC3798096 DOI: 10.1002/anie.201210317] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Revised: 03/07/2013] [Indexed: 01/14/2023]
Affiliation(s)
- Seraphine V Wegner
- Abt. Neue Materialieln und Biosysteme, Max-Planck-Institut für Intelligente Systeme, Heisenbergstrasse 3, 70596, Stuttgart, Germany
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