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Bakholdina SI, Stenkova AM, Bystritskaya EP, Sidorin EV, Kim NY, Menchinskaya ES, Gorpenchenko TY, Aminin DL, Shved NA, Solov’eva TF. Studies on the Structure and Properties of Membrane Phospholipase A 1 Inclusion Bodies Formed at Low Growth Temperatures Using GFP Fusion Strategy. Molecules 2021; 26:molecules26133936. [PMID: 34203222 PMCID: PMC8271855 DOI: 10.3390/molecules26133936] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 06/08/2021] [Accepted: 06/22/2021] [Indexed: 11/23/2022] Open
Abstract
The effect of cultivation temperatures (37, 26, and 18 °C) on the conformational quality of Yersinia pseudotuberculosis phospholipase A1 (PldA) in inclusion bodies (IBs) was studied using green fluorescent protein (GFP) as a folding reporter. GFP was fused to the C-terminus of PldA to form the PldA-GFP chimeric protein. It was found that the maximum level of fluorescence and expression of the chimeric protein is observed in cells grown at 18 °C, while at 37 °C no formation of fluorescently active forms of PldA-GFP occurs. The size, stability in denaturant solutions, and enzymatic and biological activity of PldA-GFP IBs expressed at 18 °C, as well as the secondary structure and arrangement of protein molecules inside the IBs, were studied. Solubilization of the chimeric protein from IBs in urea and SDS is accompanied by its denaturation. The obtained data show the structural heterogeneity of PldA-GFP IBs. It can be assumed that compactly packed, properly folded, proteolytic resistant, and structurally less organized, susceptible to proteolysis polypeptides can coexist in PldA-GFP IBs. The use of GFP as a fusion partner improves the conformational quality of PldA, but negatively affects its enzymatic activity. The PldA-GFP IBs are not toxic to eukaryotic cells and have the property to penetrate neuroblastoma cells. Data presented in the work show that the GFP-marker can be useful not only as target protein folding indicator, but also as a tool for studying the molecular organization of IBs, their morphology, and localization in E. coli, as well as for visualization of IBs interactions with eukaryotic cells.
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Affiliation(s)
- Svetlana I. Bakholdina
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Prospekt 100-let Vladivostoku 159, 690022 Vladivostok, Russia; (E.P.B.); (E.V.S.); (N.Y.K.); (E.S.M.); (D.L.A.)
- Correspondence: (S.I.B.); (T.F.S.); Tel.: +7-423-231-11-58 (S.I.B. & T.F.S.); Fax: +7-423-231-40-50 (S.I.B. & T.F.S.)
| | - Anna M. Stenkova
- Department of Medical Biology and Biotechnology, FEFU Campus, School of Biomedicine, Far Eastern Federal University, Russky Island Ajax Bay 10, 690922 Vladivostok, Russia; (A.M.S.); (N.A.S.)
| | - Evgenia P. Bystritskaya
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Prospekt 100-let Vladivostoku 159, 690022 Vladivostok, Russia; (E.P.B.); (E.V.S.); (N.Y.K.); (E.S.M.); (D.L.A.)
| | - Evgeniy V. Sidorin
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Prospekt 100-let Vladivostoku 159, 690022 Vladivostok, Russia; (E.P.B.); (E.V.S.); (N.Y.K.); (E.S.M.); (D.L.A.)
| | - Natalya Yu. Kim
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Prospekt 100-let Vladivostoku 159, 690022 Vladivostok, Russia; (E.P.B.); (E.V.S.); (N.Y.K.); (E.S.M.); (D.L.A.)
| | - Ekaterina S. Menchinskaya
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Prospekt 100-let Vladivostoku 159, 690022 Vladivostok, Russia; (E.P.B.); (E.V.S.); (N.Y.K.); (E.S.M.); (D.L.A.)
| | - Tatiana Yu. Gorpenchenko
- Federal Scientific Center of the East Asia Terrestrial Biodiversity, Far Eastern Branch of the Russian Academy of Sciences, Prospect 100-let Vladivostoku, 159, 690022 Vladivostok, Russia;
| | - Dmitry L. Aminin
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Prospekt 100-let Vladivostoku 159, 690022 Vladivostok, Russia; (E.P.B.); (E.V.S.); (N.Y.K.); (E.S.M.); (D.L.A.)
- Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, 100, Shih-Chuan 1st Road, Kaohsiung 80708, Taiwan
| | - Nikita A. Shved
- Department of Medical Biology and Biotechnology, FEFU Campus, School of Biomedicine, Far Eastern Federal University, Russky Island Ajax Bay 10, 690922 Vladivostok, Russia; (A.M.S.); (N.A.S.)
| | - Tamara F. Solov’eva
- G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Prospekt 100-let Vladivostoku 159, 690022 Vladivostok, Russia; (E.P.B.); (E.V.S.); (N.Y.K.); (E.S.M.); (D.L.A.)
- Correspondence: (S.I.B.); (T.F.S.); Tel.: +7-423-231-11-58 (S.I.B. & T.F.S.); Fax: +7-423-231-40-50 (S.I.B. & T.F.S.)
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Nagibina GS, Melnik TN, Glukhova KA, Uversky VN, Melnik BS. Intrinsic disorder-based design of stable globular proteins. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2020; 174:157-186. [PMID: 32828465 DOI: 10.1016/bs.pmbts.2020.05.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Directed stabilization of globular proteins via substitution of a minimal number of amino acid residues is one of the most complicated experimental tasks. In this work, we have successfully used algorithms for the evaluation of intrinsic disorder predisposition (such as PONDR® FIT and IsUnstruct) as tools for searching for the weakened regions in structured globular proteins. We have shown that the weakened regions found by these programs as regions with highest levels of predicted intrinsic disorder predisposition are a suitable target for introduction of stabilizing mutations.
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Affiliation(s)
- Galina S Nagibina
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russia
| | - Tatiana N Melnik
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russia
| | - Ksenia A Glukhova
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russia
| | - Vladimir N Uversky
- Department of Molecular Medicine and Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, United States; Laboratory of New Methods in Biology, Institute for Biological Instrumentation of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", Pushchino, Moscow Region, Russia.
| | - Bogdan S Melnik
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russia.
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Nagibina GS, Glukhova KA, Uversky VN, Melnik TN, Melnik BS. Intrinsic Disorder-Based Design of Stable Globular Proteins. Biomolecules 2019; 10:E64. [PMID: 31906016 PMCID: PMC7022990 DOI: 10.3390/biom10010064] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 12/18/2019] [Accepted: 12/20/2019] [Indexed: 11/24/2022] Open
Abstract
Directed stabilization of globular proteins via substitution of a minimal number of amino acid residues is one of the most complicated experimental tasks. This work summarizes our research on the effect of amino acid substitutions on the protein stability utilizing the outputs of the analysis of intrinsic disorder predisposition of target proteins. This allowed us to formulate the basis of one of the possible approaches to the stabilization of globular proteins. The idea is quite simple. To stabilize a protein as a whole, one needs to find its "weakest spot" and stabilize it, but the question is how this weak spot can be found in a query protein. Our approach is based on the utilization of the computational tools for the per-residue evaluation of intrinsic disorder predisposition to search for the "weakest spot" of a query protein (i.e., the region(s) with the highest local predisposition for intrinsic disorder). When such "weakest spot" is found, it can be stabilized through a limited number of point mutations by introducing order-promoting residues at hot spots, thereby increasing structural stability of a protein as a whole. Using this approach, we were able to obtain stable mutant forms of several globular proteins, such as Gαo, GFP, ribosome protein L1, and circular permutant of apical domain of GroEL.
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Affiliation(s)
- Galina S. Nagibina
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia; (G.S.N.); (K.A.G.); (T.N.M.)
| | - Ksenia A. Glukhova
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia; (G.S.N.); (K.A.G.); (T.N.M.)
| | - Vladimir N. Uversky
- Department of Molecular Medicine and Byrd Alzheimer’s Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL 33620, USA;
- Institute for Biological Instrumentation of the Russian Academy of Sciences, Federal Research Center “Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences”, 142290 Pushchino, Moscow Region, Russia
| | - Tatiana N. Melnik
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia; (G.S.N.); (K.A.G.); (T.N.M.)
| | - Bogdan S. Melnik
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia; (G.S.N.); (K.A.G.); (T.N.M.)
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Dong J, Ding X, Wang S. Purification of the recombinant green fluorescent protein from tobacco plants using alcohol/salt aqueous two-phase system and hydrophobic interaction chromatography. BMC Biotechnol 2019; 19:86. [PMID: 31818280 PMCID: PMC6902424 DOI: 10.1186/s12896-019-0590-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 11/29/2019] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND The green fluorescent protein (GFP) has been regarded as a valuable tool and widely applied as a biomarker in medical applications and diagnostics. A cost-efficient upstream expression system and an inexpensive downstream purification process will meet the demands of the GFP protein with high-purity. RESULTS The recombinant GFP was transiently expressed in an active form in agoinoculated Nicotiana benthamiana leaves by using Tobacco mosaic virus (TMV) RNA-based overexpression vector (TRBO). The yield of recombinant GFP was up to ~ 60% of total soluble proteins (TSP). Purification of recombinant GFP from the clarified lysate of N. benthaniana leaves was achieved by using an alcohol/salt aqueous two-phase system (ATPS) and following with a further hydrophobic interaction chromatography (HIC). The purification process takes only ~ 4 h and can recover 34.1% of the protein. The purity of purified GFP was more than 95% and there were no changes in its spectroscopic characteristics. CONCLUSIONS The strategy described here combines the advantages of both the economy and efficiency of plant virus-based expression platform and the simplicity and rapidity of environmentally friendly alcohol/salt ATPS. It has a considerable potential for the development of a cost-efficient alternative for production of recombinant GFP.
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Affiliation(s)
- Jie Dong
- Key Laboratory of Ministry of Education for Protection and Utilization of Special Biological Resources in the Western China, Yinchuan, 750021, People's Republic of China
- Key Laboratory of Modern Molecular Breeding for Dominant and Special Crops in Ningxia, Yinchuan, 750021, People's Republic of China
- School of Life Science, Ningxia University, 539 W. Helanshan Road, Yinchuan, Ningxia, 750021, People's Republic of China
| | - Xiangzhen Ding
- Key Laboratory of Ministry of Education for Protection and Utilization of Special Biological Resources in the Western China, Yinchuan, 750021, People's Republic of China
- Key Laboratory of Modern Molecular Breeding for Dominant and Special Crops in Ningxia, Yinchuan, 750021, People's Republic of China
- School of Life Science, Ningxia University, 539 W. Helanshan Road, Yinchuan, Ningxia, 750021, People's Republic of China
| | - Sheng Wang
- Key Laboratory of Ministry of Education for Protection and Utilization of Special Biological Resources in the Western China, Yinchuan, 750021, People's Republic of China.
- Key Laboratory of Modern Molecular Breeding for Dominant and Special Crops in Ningxia, Yinchuan, 750021, People's Republic of China.
- School of Life Science, Ningxia University, 539 W. Helanshan Road, Yinchuan, Ningxia, 750021, People's Republic of China.
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Melnik TN, Nagibina GS, Surin AK, Glukhova KA, Melnik BS. Artificial Cysteine Bridges on the Surface of Green Fluorescent Protein Affect Hydration of Its Transition and Intermediate States. Mol Biol 2018. [DOI: 10.1134/s0026893318010120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Glukhova KF, Marchenkov VV, Melnik TN, Melnik BS. Isoforms of green fluorescent protein differ from each other in solvent molecules 'trapped' inside this protein. J Biomol Struct Dyn 2016; 35:1215-1225. [PMID: 27045905 DOI: 10.1080/07391102.2016.1174737] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Green fluorescent protein (GFP) has been studied quite thoroughly, however, up to now some experimental data have not been explained explicitly. For example, under native conditions this protein can have two isoforms differing in their mobility in gel. In this case, no differences between the isoforms are revealed under denaturing conditions. In order to understand the difference in the isoforms of this protein, we have investigated GFP-cycle3 using mass spectrometry, gel electrophoresis, size exclusion chromatography, microcalorimetry, and spectroscopy methods under varying conditions. We have also designed and studied three mutant forms of this protein with substitutions of amino acid residues inside the GFP barrel. The mutations have allowed us to influence the formation of different GFP isoforms. Each of the mutant proteins has predominantly only one isoform. As a result of the performed research, it can be concluded that most likely the GFP isoforms differ in the solvent molecules 'trapped' inside the GFP barrel. In their turn, these molecules have an effect on the protein charge and consequently on its mobility at electrophoresis under native conditions.
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Affiliation(s)
- Kseniya F Glukhova
- a Institute of Protein Research , Russian Academy of Sciences , 142290 Pushchino , Moscow Region , Russia
| | - Victor V Marchenkov
- a Institute of Protein Research , Russian Academy of Sciences , 142290 Pushchino , Moscow Region , Russia
| | - Tatiana N Melnik
- a Institute of Protein Research , Russian Academy of Sciences , 142290 Pushchino , Moscow Region , Russia
| | - Bogdan S Melnik
- a Institute of Protein Research , Russian Academy of Sciences , 142290 Pushchino , Moscow Region , Russia
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Suzuki M, Ishimaru Y, Saito A, Nishigaki K. Simple preparation of green fluorescent protein conjugated with β-cyclodextrin in a site specific manner. ANAL SCI 2013; 29:811-4. [PMID: 23934562 DOI: 10.2116/analsci.29.811] [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
We have site-directedly linked a green fluorescent protein (GFP) variant and a β-cyclodextrin (β-CD) with a simple method to develop a basic complex for sophisticated supramolecules. We have confirmed β-CD grafting on GFP with several methods including matrix-assisted laser desorption/ionization linear time-of-flight mass spectrometry (MALDI-TOF MS) without protease digestion and characterized the complex as well. In consideration of the resulting properties, the product we plainly and efficiently obtained could have applications related to sensing devices and drug delivery systems.
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Affiliation(s)
- Miho Suzuki
- Department of Functional Materials and Science, Graduate School of Science and Engineering, Saitama University, 255 Shimo-okubo, Sakura, Saitama 338-8570, Japan.
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Nicholls SB, Hardy JA. Structural basis of fluorescence quenching in caspase activatable-GFP. Protein Sci 2013; 22:247-57. [PMID: 23139158 DOI: 10.1002/pro.2188] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Revised: 10/26/2012] [Accepted: 10/29/2012] [Indexed: 11/06/2022]
Abstract
Apoptosis is critical for organismal homeostasis and a wide variety of diseases. Caspases are the ultimate executors of the apoptotic programmed cell death pathway. As caspases play such a central role in apoptosis, there is significant demand for technologies to monitor caspase function. We recently developed a caspase activatable-GFP (CA-GFP) reporter. CA-GFP is unique due to its "dark" state, where chromophore maturation of the GFP is inhibited by the presence of a C-terminal peptide. Here we show that chromophore maturation is prevented because CA-GFP does not fold into the robust β-barrel of GFP until the peptide has been cleaved by active caspase. Both CA-GFP and GFP₁₋₁₀ , a split form of GFP lacking the 11th strand, have similar secondary structure, different from mature GFP. A similar susceptibility to proteolytic digestion indicates that this shared structure is not the robust, fully formed GFP β-barrel. We have developed a model that suggests that as CA-GFP is translated in vivo it follows the same folding path as wild-type GFP; however, the presence of the appended peptide does not allow CA-GFP to form the barrel of the fully matured GFP. CA-GFP is therefore held in a "pro-folding" intermediate state until the peptide is released, allowing it to continue folding into the mature barrel geometry. This new understanding of the structural basis of the dark state of the CA-GFP reporter will enable manipulation of this mechanism in the development of reporter systems for any number of cellular processes involving proteases and potentially other enzymes.
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Affiliation(s)
- Samantha B Nicholls
- Department of Chemistry, University of Massachusetts Amherst, Amherst, Massachusetts 01003, USA
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Melnik TN, Povarnitsyna TV, Glukhov AS, Melnik BS. Multi-state proteins: approach allowing experimental determination of the formation order of structure elements in the green fluorescent protein. PLoS One 2012; 7:e48604. [PMID: 23155397 PMCID: PMC3498258 DOI: 10.1371/journal.pone.0048604] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Accepted: 09/26/2012] [Indexed: 11/19/2022] Open
Abstract
The most complex problem in studying multi-state protein folding is the determination of the sequence of formation of protein intermediate states. A far more complex issue is to determine at what stages of protein folding its various parts (secondary structure elements) develop. The structure and properties of different intermediate states depend in particular on these parts. An experimental approach, named μ-analysis, which allows understanding the order of formation of structural elements upon folding of a multi-state protein was used in this study. In this approach the same elements of the protein secondary structure are “tested” by substitutions of single hydrophobic amino acids and by incorporation of cysteine bridges. Single substitutions of hydrophobic amino acids contribute to yielding information on the late stages of protein folding while incorporation of ss-bridges allows obtaining data on the initial stages of folding. As a result of such an μ-analysis, we have determined the order of formation of beta-hairpins upon folding of the green fluorescent protein.
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Affiliation(s)
- Tatiana N. Melnik
- Institute of Protein Research, RAS, Pushchino, Moscow Region, Russia
| | | | | | - Bogdan S. Melnik
- Institute of Protein Research, RAS, Pushchino, Moscow Region, Russia
- * E-mail:
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Melnik BS, Povarnitsyna TV, Glukhov AS, Melnik TN, Uversky VN. SS-Stabilizing Proteins Rationally: Intrinsic Disorder-Based Design of Stabilizing Disulphide Bridges in GFP. J Biomol Struct Dyn 2012; 29:815-24. [DOI: 10.1080/07391102.2012.10507414] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Melnik BS, Molochkov NV, Prokhorov DA, Uversky VN, Kutyshenko VP. Molecular mechanisms of the anomalous thermal aggregation of green fluorescent protein. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2011; 1814:1930-9. [DOI: 10.1016/j.bbapap.2011.07.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Revised: 07/19/2011] [Accepted: 07/19/2011] [Indexed: 11/27/2022]
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Gubala V, Lynam CCN, Nooney R, Hearty S, McDonnell B, Heydon K, O'Kennedy R, MacCraith BD, Williams DE. Kinetics of immunoassays with particles as labels: effect of antibody coupling using dendrimers as linkers. Analyst 2011; 136:2533-41. [PMID: 21541412 DOI: 10.1039/c1an15017k] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In this article, we report on poly(amidoamine) dendrimers (PAMAM) as coupling agents for recombinant single-chain (ScFv) antibodies to nanoparticle (NP) labels, for use in immunoassay. We present a simple theory for the kinetics of particle capture onto a surface by means of an antibody-antigen reaction, in which the important parameter is the fraction of the particle surface that is active for reaction. We describe how increasing the generation number of the linking dendrimers significantly increased the fraction of the NP surface that is active for antigen binding and consequently also increased the assay kinetic rates. Use of dendrimers for conjugation of the NP to the antibody resulted in a significantly higher surface coverage of active antibody, in comparison with mono-valent linker chemistry. As a direct consequence, the increase in effective avidity significantly out-weighed any effect of a decreased diffusion coefficient due to the NP, when compared to that of a molecular dye-labelled antibody. The signal to noise ratio of the G4.5 dendrimer-sensitised nanoparticles out-performed the dye-labelled antibody by approximately four-fold. Particle aggregation experiments with the multi-valent antigen CRP demonstrated reaction-limited aggregation whose rate increased significantly with increasing generation number of the dendrimer linker.
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Affiliation(s)
- Vladimir Gubala
- Biomedical Diagnostics Institute Dublin City University, Glasnevin, Ireland.
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Chew FN, Tan WS, Tey BT. Fluorescent quantitation method for differentiating the nativity of green fluorescent protein. J Biosci Bioeng 2010; 111:246-8. [PMID: 21036662 DOI: 10.1016/j.jbiosc.2010.10.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Revised: 10/04/2010] [Accepted: 10/05/2010] [Indexed: 11/29/2022]
Abstract
A gel imaging method was employed to quantitate the GFP that had been subjected to denaturation and degradation treatments. This method is able to differentiate the nativity of GFP by relating the observed changes in the position of fluorescent bands which is unable to be detected using the spectrofluorometric method.
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Affiliation(s)
- Few Ne Chew
- Department of Chemical and Environmental Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
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