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Extração e purificação de peroxidase de soja (Glycine max) por adsorção de afinidade a metal imobilizadoSousa, Kathia Assis de 23 April 2001 (has links)
Orientador: Telma Teixeira Franco / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-07-28T03:46:25Z (GMT). No. of bitstreams: 1
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Previous issue date: 2001 / Resumo: Foram investigadas estabilidade frente a pH e temperatura e condições ótimas da enzima peroxidase do extrato bruto da casca da soja (Glycine max). Foi verificada a afinidade entre a enzima e íons cobre imobilizados no gel "Chelating Sepharose FastFlow" (CSFF) e também foi estudado o efeito do pH sobre a adsorção desta enzima. Foram construídas isotennas de adsorção para a peroxidase do extrato bruto de casca da soja e para as peroxidases padrão de soja e de nabo (horseradish), para verificar a capacidade máxima de adsorção do complexo CSFF-IDA-CU2+ para estas enzimas. Curvas de ruptura para a peroxidase do caldo bruto de casca da soja foram construídas para estudar a eficiência do complexo na adsorção da enzima. A purificação da peroxidase do extrato bruto da casca da soja foi estudada na coluna HR 5/5 empacotada com o complexo CSFFIDA-CU2+ equilibrado com tampão fosfato de sódio O,IM a pH 6,0. Foi verificado que a peroxidase do extrato bruto da casca da soja apresentou condições ótimas de atividade a pH 4,5, mostrou-se estável por três horas em temperaturas entre 1 e 55°C. Foi observado que a adsorção mais seletiva da peroxidase do extrato bruto de casca da soja se deu a pH 6,0, quando 51% da enzima foi retida após dez minutos de contato entre a peroxidase e o complexo CSFF -IDA-Cu2+ a 25°C em tampão fosfato de sódio O,IM. A adsorção das peroxidases da casca da soja, padrão comercial de nabo e padrão comercial de soja no complexo CSFF-IDA-Cu2+ obedeceu ao modelo proposto por Langmuir. Com a construção das curvas de ruptura foi verificado que a pH 6,0 houve a melhor seletividade na separação da atividade de peroxidase, quando 96,9% de atividade foi recuperada. Na adsorção da peroxidase do extrato bruto da casca da soja na coluna HR 5/5 empacotada com CSFF-IDA-CU2+ a pH 6,0, foi obtido um fator de purificação de 5,9 vezes com um rendimento de 83,4% / Abstract: The conditions for the soybean hull peroxidase activity were investigated for pH and temperature. It was observed that the best pH for maximum activity was at 4.5, however the activity was only 5% reduced at pH values 5.0 and 5.5 and was 20% reduced for pH's between 6.0 and 7.0 and 45% reduced at pH 8.0. It was stable at this pH interval for four hours period, however, it lost 20% activity at pH 4.5 after one hour incubation. Best temperature for the enzyme active was 55 °C and it was stable from 1 to 55 °C for at least three hours. The affinity between the soybean hull peroxidase and copper ions immobilized in a solid matrix was investigated. The maximum capacity ofthe CSFF-IDA-CU2+ to interact with the enzyme was calculated by plotting the concentrations of the proxidase found in the liquid phase in equilibrium with the peroxidase concentrations found in the solid phase (isotherms). Breakthrough curves were built to study the efficiency ofCSFF-IDA-CU2+ bed to adsorb the peroxidase of soybean hulI and also two standards peroxidases commercially available from soybean and ITom horseradish. The effect of pH on the adsorption of the enzyme was also investigated and it was observed that the most selective adsorption of the soybean hulI peroxidase was at pH 6.0. Purification of the soybean hull peroxidase was studied in the column HR 5/5 packed with the complex CSFF-IDA-CU2+ in 100 mM phosphate buffer at pH 6.0. The adsorption of the soybean hull peroxidase, soybean and horseradish peroxidases by the CSFF-IDA-CU2+ was observed to folIow Langmuir model. The final peroxidase purified by the process developed in this work showed that the specific activity of the enzyme was about 5.9 fold higher than that of cru de extract and the yield was about 83.4% / Mestrado / Desenvolvimento de Processos Químicos / Mestre em Engenharia Química
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Purificação de fragmentos Fab humano em níquel, cobre, cobalto e zinco quelatados ao CM-Asp / Purification of human Fab fragments with CM-Asp immobilized nickel, cooper, cobalt and zincMourão, Cecília Alves, 1989- 25 August 2018 (has links)
Orientador: Sonia Maria Alves Bueno / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-25T09:14:39Z (GMT). No. of bitstreams: 1
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Previous issue date: 2014 / Resumo: As imunoglobulinas G (IgG) e seus fragmentos Fab, F(ab)¿2 e Fv apresentam aplicações proeminentes nas áreas terapêuticas e de diagnósticos. Em determinadas situações em que a região Fc é dispensável e/ou deletéria, emprega-se preferencialmente fragmentos em relação à IgG não clivada. Tais aplicações requerem um elevado grau de pureza dessas biomoléculas. O elevado custo de obtenção de fragmentos pelas técnicas convencionais justifica a investigação de outras que possam proporcionar a obtenção dessas proteínas, combinando um menor custo com um elevado grau de pureza. Neste sentido, o objetivo deste trabalho foi avaliar e comparar a eficácia dos adsorventes agarose-CM-Asp-Ni(II), agarose-CM-Asp-Co(II), agarose-CM-Asp-Cu(II) e agarose-CM-Asp-Zn(II) na purificação dos fragmentos Fab de IgG humana policlonal, a partir de uma solução de IgG clivada pela enzima papaína. O efeito do sistema tamponante, do íon metálico e do cloreto de sódio foram avaliados. A seletividade das condições cromatográficas foi avaliada por eletroforese SDS-PAGE, Western Blotting e imunodifusão radial. Os resultados indicaram que nas cromatografias conduzidas com o quelato CM-Asp-Co(II) com Hepes e Tris-HCl, na ausência de sal, os fragmentos Fab foram obtidos separados do Fc nas frações de eluição. Nas cromatografias em CM-Asp-Ni(II) com Hepes e fosfato de sódio na presença de NaCl e em CM-Asp-Cu(II) com Tris-HCl e fosfato de sódio na presença de NaCl, a biomolécula alvo foi obtida seletivamente nas frações não retidas (cromatografia negativa). Nas cromatografias em CM-Asp-Zn(II) não houve a recuperação seletiva dos fragmentos Fab. Os resultados das curvas de ruptura com os quelatos CM-Asp-Ni(II), CM-Asp-Co(II) e CM-Asp-Cu(II) revelaram a recuperação de 3,4 mg, 17,1 mg e 8,6 mg de Fab, respectivamente. Os fragmentos Fab foram obtidos com pureza superior a 90%, sendo que para o ligante CM-Asp-Cu(II), segundo o western blot, os fragmentos Fab foram separados da IgG não clivada. Os resultados obtidos nas condições cromatográficas estudadas evidenciam a potencialidade do emprego dos quelatos CM-Asp-Ni(II), CM-Asp-Co(II) e CM-Asp-Cu(II), imobilizados em agarose, para purificação de fragmentos Fab obtidos da clivagem enzimática da IgG humana policlonal / Abstract: Immunoglobulins G (IgG) and their fragments Fab, F(ab)¿2 and Fv are prominently applied as therapeutic and diagnostic tool. Fragments are preferably used rather than the uncleaved IgG, specially when the Fc portion is dispensable or prejudicial. For the mentioned applications, high purity preparations are required. The high costs associated with the conventional downstream processing of these biomolecules is the driving force to investigate purification techniques that can combine lower cost with high purification factor. Therefore, the goal of this work is to evaluate and compare the efficiency of CM-Asp-Ni(II), CM-Asp-Co(II), CM-Asp-Cu(II) and CM-Asp-Zn(II) adsorbents in the purification of Fab fragments from papain-digested human IgG. The effects of buffers, metal-ion and NaCl addition were also studied. The adsorbent/buffer selectivity towards the targeted molecule was evaluated by SDS-PAGE, Western Blotting and radial immunodiffusion assays. Chromatography with CM-Asp-Co(II) as chelated using Hepes and Tris-HCl buffers resulted in Fab recovery in the elution fractions. Whereas the chromatography with CM-Asp-Ni(II) and CM-Asp-Cu(II) both as chelated using Hepes sodium phosphate buffers with NaCl addition resulted in Fab selective recovery in non-retained fractions (negative chromatography). The adsorbent CM-Asp-Zn(II) did not show Fab selective recovery. Breakthrough curves experiments with CM-Asp-Ni(II), CM-Asp-Co(II) e CM-Asp-Cu(II) showed recovery of 3.4 mg, 17.1 mg and 8.6 mg of Fab, respectively. Fab fragments were recovered with purity higher than 90%. When chelated CM-Asp-Cu(II) was use as ligand, Fab fragments were recovery separated from intact IgG as shown in western blot. Results obtained in the chromatographic conditions studied showed the potential use of CM-Asp-Ni(II), CM-Asp-Co(II) and CM-Asp-Cu(II) immobilized in agarose for the purification of Fab fragments from cleaved human polyclonal IgG / Mestrado / Desenvolvimento de Processos Biotecnologicos / Mestra em Engenharia Química
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Développement d’outils chimiques pour l’élucidation de la biosynthèse des flavonoïdes du raisin : anthocyanes versus proanthocyanidinesChalumeau, Céline 21 December 2010 (has links)
Ces dernières années, des progrès remarquables ont été accomplis afin d’élucider la biosynthèse des flavonoïdes. Cependant les dernières étapes menant à la formation des proanthocyanidines ou tannins condensés issus de la vigne, restent à ce jour inconnues. Dans le but de déterminer si une ou plusieurs enzyme(s) spécifique(s) sont impliquées dans cette voie de biosynthèse, nous avons développé une approche de protéomique chimique, impliquant des matrices d’affinité constituées de substrats de type flavanols greffés sur un support solide. La validation de ces outils à l’aide de LDOX, une enzyme issue de Vitis vinifera a pu être menée à bien dans le cadre de ces travaux de thèse. / Remarkable progress toward the complete elucidation of the biosynthesis of flavonoids has been accomplished during the last decade, but the final step leading to proanthocyanidins still remain to be elucidated, in particular, the exact nature of starter and extension units as well as the enzymatic or non enzymatic condensation process. In order to answer whether some specific enzymes are involved in the biosynthesis of grapevine proanthocyanidins, we have developped a chemical proteomics approach, with an affinity chromatography-based tool in which a flavanol type substrate is loaded on an appropriate solid support. The validation of these tools with the LDOX enzyme from Vitis vinifera was developped and performed in this Ph.D work.
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Over-Expression, Purification And Preliminary Characterization Of Non-Structural Protein NSs From Peanut Bud Necrosis Virus-Tomato Isolate (PBNV-To)Bhushan, Lokesh 04 1900 (has links) (PDF)
No description available.
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Synthesis of Cucurbit[7]uril Based Affinity Derivatization Tags and Evaluation of their Use in the Enrichment and Identification of Carbonylated Plasma ProteinsSmith, Ashton K. 02 June 2020 (has links)
No description available.
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Proteomic Profiling of Pro and Active Matrix Metalloproteinases using Tandem Mass Spectrometry. Optimization of Affinity Chromatography and nHPLC-MALDI-MS/MS for Proteomic discrimination of Matrix Metalloproteinases in pre-clinical Cancer Model.Saleem, Saira January 2012 (has links)
Matrix metalloproteinases (MMPs) network with other biological molecules to
maintain the extracellular matrix (ECM) in normal physiology and perform
different roles. Understanding and assigning specific role to each of 24
members of these endoproteinases is impeded because of lack of specific
and efficient detection methods in biological samples. Moreover, MMP-based
anti-cancer drug development has also been challenged because, currently,
there is no robust methodology to distinguish the inactive pro-enzymes,
active enzymes or those complexed with endogenous inhibitors in biological
specimens. The objective of this project is to develop a chemical proteomics
strategy based on Matrix assisted laser desorption ionization tandem mass
spectrometry (MALDI-MS/MS) to help identify and discriminate the various
MMP forms. Firstly, a triazine dye-based ligand immobilized on
chromatography beads was utilized to assess whether it binds to
recombinant human MMPs (rhMMPs). The results highlighted that the ligand
interacts with latent forms of MMPs in agreement with the literature.
Secondly, the potential of the ligand was assessed using MALDI-MS/MS
based methodology in in vitro cancer models. Cell line culture supernatants
were used in amounts to emulate the availability of tumour biopsies in clinical
settings. The MS/MS spectral peaks specific to MMPs (MMP-2 and MMP-
14), and two endogenous inhibitors TIMP-1 and TIMP-2 were found in affinity
chromatography eluates of cell culture supernatants with higher Mascot
scores for the latter. While western blot detected MMP-2 in cell extracts,
MALDI-MS/MS did not detect MMPs because of amounts below the limit of
detection (LOD) of the instrument. Although the ligand was found to be
interacting with MMPs and detergent-free salt elution buffers improved
MALDI analysis, recovery of MMPs from biological samples was sub-optimal.
The dye ligand was observed to bind other enzymes and despite various
strategies to reduce non-specific binding of proteins or enable selective
elution did not improve MMP enrichment. Further work using methodology
described in this study is required after scaling up the MMP amounts in
biological specimen and to resolve the issue of non-specific binding of
proteins to the ligand by understanding its structure. / Shaukat Khanam Memorial Cancer Hospital and Research
Centre, Pakistan and University of Bradford
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Identificação e validação de um novo alvo funcional de um peptídeo com atividade anti-hipertensiva do veneno da Bothrops jararaca / Identification and validation of a novel functional target of a peptide from Bothrops jararaca venom with antihypertensive activityGuerreiro, Juliano Rodrigo 21 May 2009 (has links)
O BPP-10c é um decapeptídeo bioativo, rico em resíduos de prolina e é expresso em uma proteína precursora no cérebro e na glândula de veneno da Bothrops jararaca. Recentemente demonstramos que o BPP-10c tem um potente e sustentado efeito anti-hipertensivo em ratos espontaneamente hipertensos (SHR), sem, no entanto, causar qualquer efeito em ratos normotensos, por um mecanismo farmacológico independente da inibição da enzima conversora de angiotensina (ECA), levando à hipótese de que outro mecanismo poderia estar envolvido na atividade do peptídeo. Neste trabalho, usamos cromatografia de afinidade para isolar e identificar as proteínas renais com afinidade pelo BPP-10c e demonstramos que a argininosuccinato sintase (AsS) é a principal proteína a se ligar ao peptídeo. Além disso, mostramos que essa interação promove um aumento na atividade catalítica da enzima, de forma dose-dependente. A AsS é reconhecida como uma peça chave na regulação do ciclo da citrulina-óxido nítrico (NO), e sua ação é passo limitante na síntese de NO. A interação funcional do BPP-10c com a AsS foi evidenciada pelos seguintes efeitos promovidos pelo peptídeo: i) estimulação da produção de NO por células HUVEC e da produção de arginina por células HEK 293, ii) aumento da concentração plasmática de arginina em SHR. Corroborando esses achados, mostramos a reversão dos efeitos do peptídeo, inclusive sobre a pressão arterial em SHR, quando o MDLA, um inibidor específico da AsS, foi co-administrado. Em conjunto, os resultados apresentados neste trabalho sugerem que a AsS é fundamental para o efeito anti-hipertensivo do BPP-10c. Tais resultados nos levaram a propor a AsS como um novo alvo terapêutico, e o BPP-10c como molécula-líder para a geração de medicamentos para tratamento de doenças relacionadas à hipertensão arterial / BPP-10c is a bioactive proline-rich decapeptide, part of the C-type natriuretic peptide precursor, expressed in the brain and in the venom gland of Bothrops jararaca. We recently showed that BPP-10c displays a strong, sustained anti-hypertensive effect in spontaneous hypertensive rats (SHR), without causing any effect in normotensive rats, by a pharmacological mechanism independent of angiotensin converting enzyme inhibition; therefore, we hypothesized that another mechanism should be involved in the peptide activity. Here we used affinity chromatography to search for kidney cytosolic proteins with affinity for BPP-10c and demonstrate that argininosuccinate synthetase (AsS) is the major protein binding to the peptide. More importantly, this interaction activates the catalytic activity of AsS in a dose-dependent manner. AsS is recognized as an important player of the citrulline-nitric oxide (NO) cycle that represents a potential limiting step in NO synthesis. Accordingly, the functional interaction of BPP-10c and AsS was evidenced by the following effects promoted by the peptide: i) increase of NO production in human umbilical vein endothelial cell culture, and of arginine in human embryonic kidney cells; ii) increase of arginine plasma concentration in SHR. Moreover, MDLA, a specific AsS inhibitor, significantly reduced the anti-hypertensive activity of BPP-10c in SHR. These results led us to suggest AsS as a new therapeutically useful target for the development of activators, such as BPP- 10c, useful to treat hypertension related diseases
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Versatile Implementations of an Improved Cell-Free System for Protein Biosynthesis : Functional and structural studies of ribosomal protein L11 and class II release factor RF3. Novel biotechnological approach for continuous protein biosynthesis / Mångsidig Användning av ett Förbättrat Cell-Fritt System för Proteinbiosyntes : Funktionella och strukturella studier av ribosomalt protein L11 och klass II release faktor RF3. Ny bioteknologisk metod för kontinuerlig proteinbiosyntesBouakaz, Lamine January 2006 (has links)
<p>Advances in genetics, proteomics and chromatography techniques have enabled the successfully generation of a cell-free bacterial translation system composed of highly pure and active components. This system provided an ideal platform for better elucidating the mechanism of each individual step of the prokaryotic protein biosynthesis and the function of the translation factors involved in the process. </p><p>In doing so, we have discovered that the N-terminal domain or complete deletions of the ribosomal protein L11 reduced the termination efficiency of RF1 on cognate stop codons by four to six folds. The L11 deletions also conferred a two folds decrease in the missense error suggesting the increased nonsense termination accuracy of RF2 by two folds, which would clarified previous in vivo observations. </p><p>The versatility of the cell-free system has provided the additional possibility to study the effects of class II release factor RF3 mutations in mediating fast dissociation of class I release factors RF1 and RF2 from the post-termination ribosome complexes. The results show a series of mutations within RF3 conferring considerable reduction of the class I release factors recycling rate. These observations together with sequence alignment studies suggest the possible location on RF3 of the class I release factors interaction site. </p><p>In addition, the utilization of the cell-free system has made it possible to develop a new biotechnological approach for continuous production of polypeptides, based on gel filtration chromatography. The pilot trials have so far resulted in a six fold production increase of the MFTI test peptide compared to the conventional batch method.</p>
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Versatile Implementations of an Improved Cell-Free System for Protein Biosynthesis : Functional and structural studies of ribosomal protein L11 and class II release factor RF3. Novel biotechnological approach for continuous protein biosynthesis / Mångsidig Användning av ett Förbättrat Cell-Fritt System för Proteinbiosyntes : Funktionella och strukturella studier av ribosomalt protein L11 och klass II release faktor RF3. Ny bioteknologisk metod för kontinuerlig proteinbiosyntesBouakaz, Lamine January 2006 (has links)
Advances in genetics, proteomics and chromatography techniques have enabled the successfully generation of a cell-free bacterial translation system composed of highly pure and active components. This system provided an ideal platform for better elucidating the mechanism of each individual step of the prokaryotic protein biosynthesis and the function of the translation factors involved in the process. In doing so, we have discovered that the N-terminal domain or complete deletions of the ribosomal protein L11 reduced the termination efficiency of RF1 on cognate stop codons by four to six folds. The L11 deletions also conferred a two folds decrease in the missense error suggesting the increased nonsense termination accuracy of RF2 by two folds, which would clarified previous in vivo observations. The versatility of the cell-free system has provided the additional possibility to study the effects of class II release factor RF3 mutations in mediating fast dissociation of class I release factors RF1 and RF2 from the post-termination ribosome complexes. The results show a series of mutations within RF3 conferring considerable reduction of the class I release factors recycling rate. These observations together with sequence alignment studies suggest the possible location on RF3 of the class I release factors interaction site. In addition, the utilization of the cell-free system has made it possible to develop a new biotechnological approach for continuous production of polypeptides, based on gel filtration chromatography. The pilot trials have so far resulted in a six fold production increase of the MFTI test peptide compared to the conventional batch method.
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Production and delivery of recombinant subunit vaccinesAndersson, Christin January 2000 (has links)
Recombinant strategies are today dominating in thedevelopment of modern subunit vaccines. This thesis describesstrategies for the production and recovery of protein subunitimmunogens, and how genetic design of the expression vectorscan be used to adapt the immunogens for incorporation intoadjuvant systems. In addition, different strategies fordelivery of subunit vaccines by RNA or DNA immunization havebeen investigated. Attempts to create general production strategies forrecombinant protein immunogens in such a way that these areadapted for association with an adjuvant formulation wereevaluated. Different hydrophobic amino acid sequences, beingeither theoretically designed or representing transmembraneregions of bacterial or viral origin, were fused on gene leveleither N-terminally or C-terminally to allow association withiscoms. In addition, affinity tags derived fromStaphylococcus aureusprotein A (SpA) or streptococcalprotein G (SpG), were incorporated to allow efficient recoveryby means of affinity chromatography. A malaria peptide, M5,derived from the central repeat region of thePlasmodium falciparumblood-stage antigen Pf155/RESA,served as model immunogen in these studies. Furthermore,strategies forin vivoorin vitrolipidation of recombinant immunogens for iscomincorporation were also investigated, with a model immunogendeltaSAG1 derived fromToxoplasma gondii. Both strategies were found to befunctional in that the produced and affinity purified fusionproteins indeed associated with iscoms. The iscoms werefurthermore capable of inducing antigen-specific antibodyresponses upon immunization of mice, and we thus believe thatthe presented strategies offer convenient methods for adjuvantassociation. Recombinant production of a respiratory syncytial virus(RSV) candidate vaccine, BBG2Na, in baby hamster kidney(BHK-21) cells was investigated. Semliki Forest virus(SFV)-based expression vectors encoding both intracellular andsecreted forms of BBG2Na were constructed and found to befunctional. Efficient recovery of BBG2Na could be achieved bycombining serum-free production with a recovery strategy usinga product-specific affinity-column based on a combinatoriallyengineered SpA domain, with specific binding to the G proteinpart of the product. Plasmid vectors encoding cytoplasmic or secreted variants ofBBG2Na, and employing the SFV replicase for self-amplification,was constructed and evaluated for DNA immunization against RSV.Both plasmid vectors were found to be functional in terms ofBBG2Na expression and localization. Upon intramuscularimmunization of mice, the plasmid vector encoding the secretedvariant of the antigen elicited significant anti-BBG2Na titersand demonstrated lung protective efficacy in mice. This studyclearly demonstrate that protective immune responses to RSV canbe elicited in mice by DNA immunization, and that differentialtargeting of the antigens expressed by nucleic acid vaccinationcould significantly influence the immunogenicity and protectiveefficacy. We further evaluated DNA and RNA constructs based on the SFVreplicon in comparison with a conventional DNA plasmid forinduction of antibody responses against theP. falciparumPf332-derived antigen EB200. In general,the antibody responses induced were relatively low, the highestresponses surprisingly obtained with the conventional DNAplasmid. Also recombinant SFV suicide particles inducedEB200-reactive antibodies. Importantly, all immunogens inducedan immunological memory, which could be efficiently activatedby a booster injection with EB200 protein. <b>Keywords</b>: Affibody, Affinity chromatography, Affinitypurification, DNA immunization, Expression plasmid, Fusionprotein, Hydrophobic tag, Iscoms, Lipid tagging, Malaria,Mammalian cell expression, Recombinant immunogen, RespiratorySyncytial Virus, Semliki Forest virus, Serum albumin,Staphylococcus aureusprotein A, Subunit vaccine,Toxoplasma gondii
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