Immunoreactivity of S100β protein in the hippocampus of chinchilla

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Krawczyk Aleksandra

2014-03-01

Full Text Available The aim of the study was to investigate S100β protein in astrocytes of CA1 and CA3 areas of the hippocampus proper and the dentate gyrus with the hilus yet undefined in mature males of chinchilla. The presence of S100β was determined using indirect immunohistochemical peroxidase-antiperoxidase method with specific monoclonal antibody against this protein. Most of the S100β-positive cells were detected in the subgranular zone of the dentate gyrus and in the middle part of the hilus. In CA3 area, it was found that the most numerous cells with S100β are in stratum radiatum. In CA1 area, there were single astrocytes expressing this protein. This data demonstrates species differences and a large quantity of S100β immunoreactive cells in the subgranular zone of the dentate gyrus of chinchilla, which may be associated with structural reorganisation of the hippocampus and with neurogenesis, learning, and memorising process dependent on the hippocampus.

S-100 protein in the diagnosis of tuberculoid borderline tuberculoidleprosy

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Khan, A.R.

1998-01-01

A definitive diagnosis of tuberculoid and borderline tuberculoid leprosyis based on a demonstration of either acid-fast bacilli or nerve elementswithin the granulomas. On routine hematoxylin and eosin stains, the nervefibers are not easily identifiable. In this study, we used S-100 protein tohighlight the nerve elements and to count their numbers in leprosy andnon-leprosy granulomas. Skin biopsy specimens from 15 cases oftuberculoid/borderline tuberculoid leprosy and 14 cases belonging to othergranulomatous disease of the skin were stained with S-100 protein. Thesurface area of all the biopsies was calculated and the numbers of nervebundles stained with S-100 protein were counted in each specimen. The nervebundles were 15 per cm2 in leprosy cases, and 9.2 per cm2 in non-leprosycases. In addition, the leprosy cases showed longer nerve twigs that wereperpendicularly oriented to the skin surface. Immunostaining with S-100facilitated detection of nerve elements in tuberculoid/borderline tuberculoidleprosy. Also, an increased number of nerve elements were found in leprosygranulomas when compared with non-leprosy granulomas (P=<0.05). (author)

Metastasis-associated protein, S100A4 mediates cardiac fibrosis potentially through the modulation of p53 in cardiac fibroblasts

DEFF Research Database (Denmark)

Tamaki, Yodo; Iwanaga, Yoshitaka; Niizuma, Shinichiro

2013-01-01

Metastasis-associated protein, S100A4 is suggested as a marker for fibrosis in several organs. It also modulates DNA binding of p53 and affects its function. However, the functional role of S100A4 in the myocardium has remained unclear. Therefore, we investigated the role of S100A4 and its relati...

Significance of the S100A4 protein in psoriasis

DEFF Research Database (Denmark)

Zibert, John R; Skov, Lone; Thyssen, Jacob P

2010-01-01

the expression and significance of S100A4 in psoriasis. We found significant upregulation of S100A4 in the dermis of psoriatic skin compared with normal skin. This pattern of S100A4 expression differs considerably from that of other S100 proteins, S100A7 and S100A8/9, with predominant expression in the epidermis...... of psoriasis. Furthermore, we revealed a massive release of the biologically active forms of S100A4 from psoriatic skin. Interestingly, we found stabilization (increase) of p53 in the basal layer of epidermis in close proximity to cells expressing S100A4. To examine the possible implication of S100A4...... in the pathogenesis of psoriasis, we analyzed the effect of S100A4 blocking antibodies in a human psoriasis xenograft SCID mouse model and observed a significant reduction of the epidermal thickness and impairment in cell proliferation and dermal vascularization. In conclusion, we showed strong upregulation...

Sensitization of interferon-γ induced apoptosis in human osteosarcoma cells by extracellular S100A4

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Pedersen, Kjetil Boye; Andersen, Kristin; Fodstad, Øystein; Mælandsmo, Gunhild Mari

2004-01-01

S100A4 is a small Ca 2+ -binding protein of the S100 family with metastasis-promoting properties. Recently, secreted S100A4 protein has been shown to possess a number of functions, including induction of angiogenesis, stimulation of cell motility and neurite extension. Cell cultures from two human osteosarcoma cell lines, OHS and its anti-S100A4 ribozyme transfected counterpart II-11b, was treated with IFN-γ and recombinant S100A4 in order to study the sensitizing effects of extracellular S100A4 on IFN-γ mediated apoptosis. Induction of apoptosis was demonstrated by DNA fragmentation, cleavage of poly (ADP-ribose) polymerase and Lamin B. In the present work, we found that the S100A4-expressing human osteosarcoma cell line OHS was more sensitive to IFN-γ-mediated apoptosis than the II-11b cells. S100A4 protein was detected in conditioned medium from OHS cells, but not from II-11b cells, and addition of recombinant S100A4 to the cell medium sensitized II-11b cells to apoptosis induced by IFN-γ. The S100A4/IFN-γ-mediated induction of apoptosis was shown to be independent of caspase activation, but dependent on the formation of reactive oxygen species. Furthermore, addition of extracellular S100A4 was demonstrated to activate nuclear factor-κB (NF-κB). In conclusion, we have shown that S100A4 sensitizes osteosarcoma cells to IFN-γ-mediated induction of apoptosis. Additionally, extracellular S100A4 activates NF-κB, but whether these events are causally related remains unknown

A Bacillus megaterium System for the Production of Recombinant Proteins and Protein Complexes.

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Biedendieck, Rebekka

2016-01-01

For many years the Gram-positive bacterium Bacillus megaterium has been used for the production and secretion of recombinant proteins. For this purpose it was systematically optimized. Plasmids with different inducible promoter systems, with different compatible origins, with small tags for protein purification and with various specific signals for protein secretion were combined with genetically improved host strains. Finally, the development of appropriate cultivation conditions for the production strains established this organism as a bacterial cell factory even for large proteins. Along with the overproduction of individual proteins the organism is now also used for the simultaneous coproduction of up to 14 recombinant proteins, multiple subsequently interacting or forming protein complexes. Some of these recombinant strains are successfully used for bioconversion or the biosynthesis of valuable components including vitamins. The titers in the g per liter scale for the intra- and extracellular recombinant protein production prove the high potential of B. megaterium for industrial applications. It is currently further enhanced for the production of recombinant proteins and multi-subunit protein complexes using directed genetic engineering approaches based on transcriptome, proteome, metabolome and fluxome data.

Development of a reverse genetics system to generate a recombinant Ebola virus Makona expressing a green fluorescent protein

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Albariño, César G., E-mail: calbarino@cdc.gov; Wiggleton Guerrero, Lisa; Lo, Michael K.; Nichol, Stuart T.; Towner, Jonathan S.

2015-10-15

Previous studies have demonstrated the potential application of reverse genetics technology in studying a broad range of aspects of viral biology, including gene regulation, protein function, cell entry, and pathogenesis. Here, we describe a highly efficient reverse genetics system used to generate recombinant Ebola virus (EBOV) based on a recent isolate from a human patient infected during the 2014–2015 outbreak in Western Africa. We also rescued a recombinant EBOV expressing a fluorescent reporter protein from a cleaved VP40 protein fusion. Using this virus and an inexpensive method to quantitate the expression of the foreign gene, we demonstrate its potential usefulness as a tool for screening antiviral compounds and measuring neutralizing antibodies. - Highlights: • Recombinant Ebola virus (EBOV) derived from Makona variant was rescued. • New protocol for viral rescue allows 100% efficiency. • Modified EBOV expresses a green fluorescent protein from a VP40-fused protein. • Modified EBOV was tested as tool to screen antiviral compounds and measure neutralizing antibodies.

Development of a reverse genetics system to generate a recombinant Ebola virus Makona expressing a green fluorescent protein

International Nuclear Information System (INIS)

Albariño, César G.; Wiggleton Guerrero, Lisa; Lo, Michael K.; Nichol, Stuart T.; Towner, Jonathan S.

2015-01-01

Previous studies have demonstrated the potential application of reverse genetics technology in studying a broad range of aspects of viral biology, including gene regulation, protein function, cell entry, and pathogenesis. Here, we describe a highly efficient reverse genetics system used to generate recombinant Ebola virus (EBOV) based on a recent isolate from a human patient infected during the 2014–2015 outbreak in Western Africa. We also rescued a recombinant EBOV expressing a fluorescent reporter protein from a cleaved VP40 protein fusion. Using this virus and an inexpensive method to quantitate the expression of the foreign gene, we demonstrate its potential usefulness as a tool for screening antiviral compounds and measuring neutralizing antibodies. - Highlights: • Recombinant Ebola virus (EBOV) derived from Makona variant was rescued. • New protocol for viral rescue allows 100% efficiency. • Modified EBOV expresses a green fluorescent protein from a VP40-fused protein. • Modified EBOV was tested as tool to screen antiviral compounds and measure neutralizing antibodies

Molecular dynamics simulation of S100B protein to explore ligand blockage of the interaction with p53 protein

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Zhou, Zhigang; Li, Yumin

2009-10-01

As a tumor suppressor, p53 plays an important role in cancer suppression. The biological function of p53 as a tumor suppressor is disabled when it binds to S100B. Developing the ligands to block the S100B-p53 interaction has been proposed as one of the most important approaches to the development of anti-cancer agents. We screened a small compound library against the binding interface of S100B and p53 to identify potential compounds to interfere with the interaction. The ligand-binding effect on the S100B-p53 interaction was explored by molecular dynamics at the atomic level. The results show that the ligand bound between S100B and p53 propels the two proteins apart by about 2 Å compared to the unligated S100B-p53 complex. The binding affinity of S100B and p53 decreases by 8.5-14.6 kcal/mol after a ligand binds to the interface from the original unligated state of the S100B-p53 complex. Ligand-binding interferes with the interaction of S100B and p53. Such interference could impact the association of S100B and p53, which would free more p53 protein from the pairing with S100B and restore the biological function of p53 as a tumor suppressor. The analysis of the binding mode and ligand structural features would facilitate our effort to identify and design ligands to block S100B-p53 interaction effectively. The results from the work suggest that developing ligands targeting the interface of S100B and p53 could be a promising approach to recover the normal function of p53 as a tumor suppressor.

The metastasis-promoting S100A4 protein confers neuroprotection in brain injury

DEFF Research Database (Denmark)

Dmytriyeva, Oksana; Pankratova, Stanislava; Owczarek, Sylwia

2012-01-01

and downregulating the neuroprotective protein metallothionein I+II. We identify two neurotrophic motifs in S100A4 and show that these motifs are neuroprotective in animal models of brain trauma. Finally, we find that S100A4 rescues neurons via the Janus kinase/STAT pathway and, partially, the interleukin-10......Identification of novel pro-survival factors in the brain is paramount for developing neuroprotective therapies. The multifunctional S100 family proteins have important roles in many human diseases and are also upregulated by brain injury. However, S100 functions in the nervous system remain...... unclear. Here we show that the S100A4 protein, mostly studied in cancer, is overexpressed in the damaged human and rodent brain and released from stressed astrocytes. Genetic deletion of S100A4 exacerbates neuronal loss after brain trauma or excitotoxicity, increasing oxidative cell damage...

Recombinant Collagenlike Proteins

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Fertala, Andzej

2007-01-01

A group of collagenlike recombinant proteins containing high densities of biologically active sites has been invented. The method used to express these proteins is similar to a method of expressing recombinant procollagens and collagens described in U. S. Patent 5,593,859, "Synthesis of human procollagens and collagens in recombinant DNA systems." Customized collagenous proteins are needed for biomedical applications. In particular, fibrillar collagens are attractive for production of matrices needed for tissue engineering and drug delivery. Prior to this invention, there was no way of producing customized collagenous proteins for these and other applications. Heretofore, collagenous proteins have been produced by use of such biological systems as yeasts, bacteria, and transgenic animals and plants. These products are normal collagens that can also be extracted from such sources as tendons, bones, and hides. These products cannot be made to consist only of biologically active, specific amino acid sequences that may be needed for specific applications. Prior to this invention, it had been established that fibrillar collagens consist of domains that are responsible for such processes as interaction with cells, binding of growth factors, and interaction with a number of structural proteins present in the extracellular matrix. A normal collagen consists of a sequence of domains that can be represented by a corresponding sequence of labels, e.g., D1D2D3D4. A collagenlike protein of the present invention contains regions of collagen II that contain multiples of a single domain (e.g., D1D1D1D1 or D4D4D4D4) chosen for its specific biological activity. By virtue of the multiplicity of the chosen domain, the density of sites having that specific biological activity is greater than it is in a normal collagen. A collagenlike protein according to this invention can thus be made to have properties that are necessary for tissue engineering.

Recombinant Protein Truncation Strategy for Inducing Bactericidal Antibodies to the Macrophage Infectivity Potentiator Protein of Neisseria meningitidis and Circumventing Potential Cross-Reactivity with Human FK506-Binding Proteins

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Bielecka, Magdalena K.; Devos, Nathalie; Gilbert, Mélanie; Hung, Miao-Chiu; Weynants, Vincent; Heckels, John E.

2014-01-01

A recombinant macrophage infectivity potentiator (rMIP) protein of Neisseria meningitidis induces significant serum bactericidal antibody production in mice and is a candidate meningococcal vaccine antigen. However, bioinformatics analysis of MIP showed some amino acid sequence similarity to human FK506-binding proteins (FKBPs) in residues 166 to 252 located in the globular domain of the protein. To circumvent the potential concern over generating antibodies that could recognize human proteins, we immunized mice with recombinant truncated type I rMIP proteins that lacked the globular domain and the signal leader peptide (LP) signal sequence (amino acids 1 to 22) and contained the His purification tag at either the N or C terminus (C-term). The immunogenicity of truncated rMIP proteins was compared to that of full (i.e., full-length) rMIP proteins (containing the globular domain) with either an N- or C-terminal His tag and with or without the LP sequence. By comparing the functional murine antibody responses to these various constructs, we determined that C-term His truncated rMIP (−LP) delivered in liposomes induced high levels of antibodies that bound to the surface of wild-type but not Δmip mutant meningococci and showed bactericidal activity against homologous type I MIP (median titers of 128 to 256) and heterologous type II and III (median titers of 256 to 512) strains, thereby providing at least 82% serogroup B strain coverage. In contrast, in constructs lacking the LP, placement of the His tag at the N terminus appeared to abrogate bactericidal activity. The strategy used in this study would obviate any potential concerns regarding the use of MIP antigens for inclusion in bacterial vaccines. PMID:25452551

Recombinant protein truncation strategy for inducing bactericidal antibodies to the macrophage infectivity potentiator protein of Neisseria meningitidis and circumventing potential cross-reactivity with human FK506-binding proteins.

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Bielecka, Magdalena K; Devos, Nathalie; Gilbert, Mélanie; Hung, Miao-Chiu; Weynants, Vincent; Heckels, John E; Christodoulides, Myron

2015-02-01

A recombinant macrophage infectivity potentiator (rMIP) protein of Neisseria meningitidis induces significant serum bactericidal antibody production in mice and is a candidate meningococcal vaccine antigen. However, bioinformatics analysis of MIP showed some amino acid sequence similarity to human FK506-binding proteins (FKBPs) in residues 166 to 252 located in the globular domain of the protein. To circumvent the potential concern over generating antibodies that could recognize human proteins, we immunized mice with recombinant truncated type I rMIP proteins that lacked the globular domain and the signal leader peptide (LP) signal sequence (amino acids 1 to 22) and contained the His purification tag at either the N or C terminus (C-term). The immunogenicity of truncated rMIP proteins was compared to that of full (i.e., full-length) rMIP proteins (containing the globular domain) with either an N- or C-terminal His tag and with or without the LP sequence. By comparing the functional murine antibody responses to these various constructs, we determined that C-term His truncated rMIP (-LP) delivered in liposomes induced high levels of antibodies that bound to the surface of wild-type but not Δmip mutant meningococci and showed bactericidal activity against homologous type I MIP (median titers of 128 to 256) and heterologous type II and III (median titers of 256 to 512) strains, thereby providing at least 82% serogroup B strain coverage. In contrast, in constructs lacking the LP, placement of the His tag at the N terminus appeared to abrogate bactericidal activity. The strategy used in this study would obviate any potential concerns regarding the use of MIP antigens for inclusion in bacterial vaccines. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Impact of protein uptake and degradation on recombinant protein secretion in yeast

DEFF Research Database (Denmark)

Tyo, Keith E. J.; Liu, Zihe; Magnusson, Ylva

2014-01-01

Protein titers, a key bioprocessing metric, depend both on the synthesis of protein and the degradation of protein. Secreted recombinant protein production in Saccharomyces cerevisiae is an attractive platform as minimal media can be used for cultivation, thus reducing fermentation costs...... and transcriptomics, we identify metabolic and regulatory markers that are consistent with uptake of whole proteins by endocytosis, followed by intracellular degradation and catabolism of substituent amino acids. Uptake and degradation of recombinant protein products may be common in S. cerevisiae protein secretion...... and simplifying downstream purification, compared to other systems that require complex media. As such, engineering S. cerevisiae to improve titers has been then the subject of significant attention, but the majority of previous efforts have been focused on improving protein synthesis. Here, we characterize...

Molecular mechanisms of Ca(2+) signaling in neurons induced by the S100A4 protein

DEFF Research Database (Denmark)

Kiryushko, Darya; Novitskaya, Vera; Soroka, Vladislav

2006-01-01

The S100A4 protein belongs to the S100 family of vertebrate-specific proteins possessing both intra- and extracellular functions. In the nervous system, high levels of S100A4 expression are observed at sites of neurogenesis and lesions, suggesting a role of the protein in neuronal plasticity. Ext...... at the cell surface. Thus, glycosaminoglycans may act as coreceptors of S100 proteins in neurons. This may provide a mechanism by which S100 proteins could locally regulate neuronal plasticity in connection with brain lesions and neurological disorders....

Recombinant protein blends: silk beyond natural design.

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Dinjaski, Nina; Kaplan, David L

2016-06-01

Recombinant DNA technology and new material concepts are shaping future directions in biomaterial science for the design and production of the next-generation biomaterial platforms. Aside from conventionally used synthetic polymers, numerous natural biopolymers (e.g., silk, elastin, collagen, gelatin, alginate, cellulose, keratin, chitin, polyhydroxyalkanoates) have been investigated for properties and manipulation via bioengineering. Genetic engineering provides a path to increase structural and functional complexity of these biopolymers, and thereby expand the catalog of available biomaterials beyond that which exists in nature. In addition, the integration of experimental approaches with computational modeling to analyze sequence-structure-function relationships is starting to have an impact in the field by establishing predictive frameworks for determining material properties. Herein, we review advances in recombinant DNA-mediated protein production and functionalization approaches, with a focus on hybrids or combinations of proteins; recombinant protein blends or 'recombinamers'. We highlight the potential biomedical applications of fibrous protein recombinamers, such as Silk-Elastin Like Polypeptides (SELPs) and Silk-Bacterial Collagens (SBCs). We also discuss the possibility for the rationale design of fibrous proteins to build smart, stimuli-responsive biomaterials for diverse applications. We underline current limitations with production systems for these proteins and discuss the main trends in systems/synthetic biology that may improve recombinant fibrous protein design and production. Copyright © 2016. Published by Elsevier Ltd.

Heparin-binding peptide as a novel affinity tag for purification of recombinant proteins.

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Morris, Jacqueline; Jayanthi, Srinivas; Langston, Rebekah; Daily, Anna; Kight, Alicia; McNabb, David S; Henry, Ralph; Kumar, Thallapuranam Krishnaswamy Suresh

2016-10-01

Purification of recombinant proteins constitutes a significant part of the downstream processing in biopharmaceutical industries. Major costs involved in the production of bio-therapeutics mainly depend on the number of purification steps used during the downstream process. Affinity chromatography is a widely used method for the purification of recombinant proteins expressed in different expression host platforms. Recombinant protein purification is achieved by fusing appropriate affinity tags to either N- or C- terminus of the target recombinant proteins. Currently available protein/peptide affinity tags have proved quite useful in the purification of recombinant proteins. However, these affinity tags suffer from specific limitations in their use under different conditions of purification. In this study, we have designed a novel 34-amino acid heparin-binding affinity tag (HB-tag) for the purification of recombinant proteins expressed in Escherichia coli (E. coli) cells. HB-tag fused recombinant proteins were overexpressed in E. coli in high yields. A one-step heparin-Sepharose-based affinity chromatography protocol was developed to purify HB-fused recombinant proteins to homogeneity using a simple sodium chloride step gradient elution. The HB-tag has also been shown to facilitate the purification of target recombinant proteins from their 8 M urea denatured state(s). The HB-tag has been demonstrated to be successfully released from the fusion protein by an appropriate protease treatment to obtain the recombinant target protein(s) in high yields. Results of the two-dimensional NMR spectroscopy experiments indicate that the purified recombinant target protein(s) exist in the native conformation. Polyclonal antibodies raised against the HB-peptide sequence, exhibited high binding specificity and sensitivity to the HB-fused recombinant proteins (∼10 ng) in different crude cell extracts obtained from diverse expression hosts. In our opinion, the HB-tag provides a

Recombinant human bone morphogenetic protein induces bone formation

International Nuclear Information System (INIS)

Wang, E.A.; Rosen, V.; D'Alessandro, J.S.; Bauduy, M.; Cordes, P.; Harada, T.; Israel, D.I.; Hewick, R.M.; Kerns, K.M.; LaPan, P.; Luxenberg, D.P.; McQuaid, D.; Moutsatsos, I.K.; Nove, J.; Wozney, J.M.

1990-01-01

The authors have purified and characterized active recombinant human bone morphogenetic protein (BMP) 2A. Implantation of the recombinant protein in rats showed that a single BMP can induce bone formation in vivo. A dose-response and time-course study using the rat ectopic bone formation assay revealed that implantation of 0.5-115 μg of partially purified recombinant human BMP-2A resulted in cartilage by day 7 and bone formation by day 14. The time at which bone formation occurred was dependent on the amount of BMP-2A implanted; at high doses bone formation could be observed at 5 days. The cartilage- and bone-inductive activity of the recombinant BMP-2A is histologically indistinguishable from that of bone extracts. Thus, recombinant BMP-2A has therapeutic potential to promote de novo bone formation in humans

Improving recombinant protein purification yield

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Production of adequate amounts of recombinant proteins is essential for antibody production, biochemical activity study, and structural determination during the post-genomic era. It’s technologically challenging and a limiting factor for tung oil research because analytical reagents such as high qua...

A Generic Protocol for Intracellular Expression of Recombinant Proteins in Bacillus subtilis.

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Phan, Trang; Huynh, Phuong; Truong, Tuom; Nguyen, Hoang

2017-01-01

Bacillus subtilis (B. subtilis) is a potential and attractive host for the production of recombinant proteins. Different expression systems for B. subtilis have been developed recently, and various target proteins have been recombinantly synthesized and purified using this host. In this chapter, we introduce a generic protocol to express a recombinant protein in B. subtilis. It includes protocols for (1) using our typical expression vector (plasmid pHT254) to introduce a target gene, (2) transformation of the target vector into B. subtilis, and (3) evaluation of the actual expression of a recombinant protein.

Role of S100A12 in the pathogenesis of osteoarthritis

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Nakashima, Motoshige [Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Sakai, Tadahiro, E-mail: tadsakai@med.nagoya-u.ac.jp [Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Hiraiwa, Hideki; Hamada, Takashi; Omachi, Takaaki [Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Ono, Yohei [Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Department of Anatomy and Cell Biology, Brody School of Medicine, East Carolina University, 600 Moye Blvd., Greenville, NC 27834 (United States); Inukai, Norio [Department of Orthopaedic Surgery, Nishio Municipal Hospital, 6 Kumami-cho, Nishio 445-8510 (Japan); Ishizuka, Shinya; Matsukawa, Tetsuya; Oda, Tomoyuki; Takamatsu, Akira; Yamashita, Satoshi; Ishiguro, Naoki [Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan)

2012-06-08

Highlights: Black-Right-Pointing-Pointer This is the first report of S100A12 expression in human OA articular cartilages. Black-Right-Pointing-Pointer Exogenous S100A12 increased the production of MMP13 and VEGF in OA chondrocytes. Black-Right-Pointing-Pointer Soluble RAGE suppressed the increased production of MMP13 and VEGF. Black-Right-Pointing-Pointer p38MAPK and NF-{kappa}B inhibitors abrogated S100A12-induced MMP13 and VEGF production. Black-Right-Pointing-Pointer S100A12 may contribute to OA progression by increasing MMP13 and VEGF production. -- Abstract: S100A12 is a member of the S100 protein family, which are intracellular calcium-binding proteins. Although there are many reports on the involvement of S100A12 in inflammatory diseases, its presence in osteoarthritic cartilage has not been reported. The purpose of this study was to investigate the expression of S100A12 in human articular cartilage in osteoarthritis (OA) and to evaluate the role of S100A12 in human OA chondrocytes. We analyzed S100A12 expression by immunohistochemical staining of cartilage samples obtained from OA and non-OA patients. In addition, chondrocytes were isolated from knee cartilage of OA patients and treated with recombinant human S100A12. Real-time RT-PCR was performed to analyze mRNA expression. Protein production of matrix metalloproteinase 13 (MMP-13) and vascular endothelial growth factor (VEGF) in the culture medium were measured by ELISA. Immunohistochemical analyses revealed that S100A12 expression was markedly increased in OA cartilages. Protein production and mRNA expression of MMP-13 and VEGF in cultured OA chondrocytes were significantly increased by treatment with exogenous S100A12. These increases in mRNA expression and protein production were suppressed by administration of soluble receptor for advanced glycation end products (RAGE). Both p38 mitogen-activated protein kinase (MAPK) and nuclear factor-{kappa}B (NF-{kappa}B) inhibitors also suppressed the increases

Serum S-100β protein as a biomarker for brain damage in patients with encephalopathy

International Nuclear Information System (INIS)

Takeda, Munekazu; Yaguchi, Arino; Yamada, Sou; Nagai, Atsushi; Yuzawa, Junji

2008-01-01

Cerebrospinal fluid concentrations of S-100β protein, an acidic calcium-binding protein found in astrocytes and Schwann cells, increase after central nervous system damage. Serum S-100β protein, thus, has been expected to be a biochemical marker of brain cell damage. Several reports show a relation between severity of head injury and serum S-100β protein levels, although, there are still not significant advances in the study of S-100β regarding the prediction of the clinical outcome in brain diseases. The objective of the present study was to verify S-100β as a marker for the clinical outcome in patients with encephalopathy. Serum S-100β protein concentrations (pg/ml) were measured daily using enzyme-linked immunosorbent assay (ELISA) until discharge from the intensive care unit (ICU) in 82 patients (54 men, 28 women; age 20-93 years [mean 61.0±19.2]) with moderate or severe encephalopathy. There were 50 survivors and 32 non-survivors. S-100β levels were significantly lower in survivors (240.2 pg/ml) than in non-survivors (1,594.8 pg/ml) from day 1 until ICU discharge. The electroencephalogram (EEG) and computed tomography (CT) abnormalities were correlated with S-100β levels. The optimal cut-off value at 451.2 pg/ml calculated from receiver operating characteristic (ROC) curve analysis showed the sensitivity of 80.2% and specificity of 78.1% for ICU mortality. Our results indicate that serum S-100β protein could be a useful biomarker to assess brain damage and predict prognosis in patients with encephalopathy. (author)

Manufacturing of recombinant therapeutic proteins in microbial systems.

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Graumann, Klaus; Premstaller, Andreas

2006-02-01

Recombinant therapeutic proteins have gained enormous importance for clinical applications. The first recombinant products have been produced in E. coli more than 20 years ago. Although with the advent of antibody-based therapeutics mammalian expression systems have experienced a major boost, microbial expression systems continue to be widely used in industry. Their intrinsic advantages, such as rapid growth, high yields and ease of manipulation, make them the premier choice for expression of non-glycosylated peptides and proteins. Innovative product classes such as antibody fragments or alternative binding molecules will further expand the use of microbial systems. Even more, novel, engineered production hosts and integrated technology platforms hold enormous potential for future applications. This review summarizes current applications and trends for development, production and analytical characterization of recombinant therapeutic proteins in microbial systems.

Reactions of chicken sera to recombinant Campylobacter jejuni flagellar proteins.

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Yeh, Hung-Yueh; Hiett, Kelli L; Line, John E

2015-03-01

Campylobacter jejuni is a Gram-negative spiral rod bacterium and is the leading but underreported bacterial food-borne pathogen that causes human campylobacteriosis worldwide. Raw or undercooked poultry products are regarded as a major source for human infection. C. jejuni flagella have been implicated in colonization and adhesion to the mucosal surface of chicken gastrointestinal tracts. Therefore, flagellar proteins would be the excellent targets for further investigation. In this report, we used the recombinant technology to generate a battery of C. jejuni flagellar proteins, which were purified by His tag affinity chromatography and determined antigenic profiles of these recombinant flagellar proteins using sera from chickens older than 6 weeks of age. The immunoblot results demonstrate that each chicken serum reacted to various numbers of recombinant flagellar proteins. Among these recombinant proteins, chicken sera reacted predominantly to the FlgE1, FlgK, FlhF, FliG and FliY proteins. These antibody screening results provide a rationale for further evaluation of these recombinant flagellar proteins as potential vaccines for chickens to improve food safety as well as investigation of host immune response to C. jejuni.

Detection and significance of S-100 protein and NSE during mild hypothermia cardiopulmonary bypass

International Nuclear Information System (INIS)

Liu Xiuqin; Jin Mu; Tan Jiefang; Huang Wenqi; Chen Bingxue; Huang Weiming; Huang Xiongqing

2001-01-01

To observe dynamic changes of S-100 protein and NSE during mild hypothermia cardiopulmonary bypass (CPB), the venous blood samples of 25 patients with elective cardiac surgery were obtained simultaneously from the left artery and left jugular bulb before CPB(A), hypothermia period (32-35 degree C) (B) and rewarming to 36 degree C (C) during CPB, 30 minutes (D), 4-6 hours (E) and 24 hours (F) after CPB. Plasma S-100 protein concentration was determined by chemiluminescence immunoassay, and NSE level was determined by radioimmunoassay. The results showed that the levels of S-100 protein and NSE increased significantly during CPB, and NSE peaked at 30 minutes (D) after CPB. It suggested the central nervous system dysfunctions. The S-100 protein and NSE concentrations decreased gradually and retuned to normal nearly (F) after mild hypothermia CPB. It suggested that there were not obvious central nervous system dysfunctions

Factors Affecting the Binding of a Recombinant Heavy Metal-Binding Domain (CXXC motif Protein to Heavy Metals

Directory of Open Access Journals (Sweden)

Kamala Boonyodying

2012-06-01

Full Text Available A number of heavy metal-binding proteins have been used to study bioremediation. CXXC motif, a metal binding domain containing Cys-X-X-Cys motif, has been identified in various organisms. These proteins are capable of binding various types of heavy metals. In this study, heavy metal binding domain (CXXC motif recombinant protein encoded from mcsA gene of S. aureus were cloned and overexpressed in Escherichia coli. The factors involved in the metal-binding activity were determined in order to analyze the potential of recombinant protein for bioremediation. A recombinant protein can be bound to Cd2+, Co2+, Cu2+ and Zn2+. The thermal stability of a recombinant protein was tested, and the results showed that the metal binding activity to Cu2+ and Zn2+ still exist after treating the protein at 85ºC for 30 min. The temperature and pH that affected the metal binding activity was tested and the results showed that recombinant protein was still bound to Cu2+ at 65ºC, whereas a pH of 3-7 did not affect the metal binding E. coli harboring a pRset with a heavy metal-binding domain CXXC motif increased the resistance of heavy metals against CuCl2 and CdCl2. This study shows that metal binding domain (CXXC motif recombinant protein can be effectively bound to various types of heavy metals and may be used as a potential tool for studying bioremediation.

S100A10 protein expression is associated with oxaliplatin sensitivity in human colorectal cancer cells

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Suzuki Sayo

2011-12-01

Full Text Available Abstract Background Individual responses to oxaliplatin (L-OHP-based chemotherapy remain unpredictable. The objective of our study was to find candidate protein markers for tumor sensitivity to L-OHP from intracellular proteins of human colorectal cancer (CRC cell lines. We performed expression difference mapping (EDM analysis of whole cell lysates from 11 human CRC cell lines with different sensitivities to L-OHP by using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS, and identified a candidate protein by liquid chromatography/mass spectrometry ion trap time-of-flight (LCMS-IT-TOF. Results Of the qualified mass peaks obtained by EDM analysis, 41 proteins were differentially expressed in 11 human colorectal cancer cell lines. Among these proteins, the peak intensity of 11.1 kDa protein was strongly correlated with the L-OHP sensitivity (50% inhibitory concentrations (P R2 = 0.80. We identified this protein as Protein S100-A10 (S100A10 by MS/MS ion search using LCMS-IT-TOF. We verified its differential expression and the correlation between S100A10 protein expression levels in drug-untreated CRC cells and their L-OHP sensitivities by Western blot analyses. In addition, S100A10 protein expression levels were not correlated with sensitivity to 5-fluorouracil, suggesting that S100A10 is more specific to L-OHP than to 5-fluorouracil in CRC cells. S100A10 was detected in cell culture supernatant, suggesting secretion out of cells. Conclusions By proteomic approaches including SELDI technology, we have demonstrated that intracellular S100A10 protein expression levels in drug-untreated CRC cells differ according to cell lines and are significantly correlated with sensitivity of CRC cells to L-OHP exposure. Our findings provide a new clue to searching predictive markers of the response to L-OHP, suggesting that S100A10 is expected to be one of the candidate protein markers.

Utilizing protein-lean coproducts from corn containing recombinant pharmaceutical proteins for ethanol production.

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Paraman, Ilankovan; Moeller, Lorena; Scott, M Paul; Wang, Kan; Glatz, Charles E; Johnson, Lawrence A

2010-10-13

Protein-lean fractions of corn (maize) containing recombinant (r) pharmaceutical proteins were evaluated as a potential feedstock to produce fuel ethanol. The levels of residual r-proteins in the coproduct, distillers dry grains with solubles (DDGS), were determined. Transgenic corn lines containing recombinant green fluorescence protein (r-GFP) and a recombinant subunit vaccine of Escherichia coli enterotoxin (r-LTB), primarily expressed in endosperm, and another two corn lines containing recombinant human collagen (r-CIα1) and r-GFP, primarily expressed in germ, were used as model systems. The kernels were either ground and used for fermentation or dry fractionated to recover germ-rich fractions prior to grinding for fermentation. The finished beers of whole ground kernels and r-protein-spent endosperm solids contained 127-139 and 138-155 g/L ethanol concentrations, respectively. The ethanol levels did not differ among transgenic and normal corn feedstocks, indicating the residual r-proteins did not negatively affect ethanol production. r-Protein extraction and germ removal also did not negatively affect fermentation of the remaining mass. Most r-proteins were inactivated during the mashing process used to prepare corn for fermentation. No functionally active r-GFP or r-LTB proteins were found after fermentation of the r-protein-spent solids; however, a small quantity of residual r-CIα1 was detected in DDGS, indicating that the safety of DDGS produced from transgenic grain for r-protein production needs to be evaluated for each event. Protease treatment during fermentation completely hydrolyzed the residual r-CIα1, and no residual r-proteins were detectable in DDGS.

Recombinant pinoresinol/lariciresinol reductase, recombinant dirigent protein, and methods of use

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Lewis, Norman G.; Davin, Laurence B.; Dinkova-Kostova, Albena T.; Fujita, Masayuki; Gang, David R.; Sarkanen, Simo; Ford, Joshua D.

2001-04-03

Dirigent proteins and pinoresinol/lariciresinol reductases have been isolated, together with cDNAs encoding dirigent proteins and pinoresinol/lariciresinol reductases. Accordingly, isolated DNA sequences are provided which code for the expression of dirigent proteins and pinoresinol/lariciresinol reductases. In other aspects, replicable recombinant cloning vehicles are provided which code for dirigent proteins or pinoresinol/lariciresinol reductases or for a base sequence sufficiently complementary to at least a portion of dirigent protein or pinoresinol/lariciresinol reductase DNA or RNA to enable hybridization therewith. In yet other aspects, modified host cells are provided that have been transformed, transfected, infected and/or injected with a recombinant cloning vehicle and/or DNA sequence encoding dirigent protein or pinoresinol/lariciresinol reductase. Thus, systems and methods are provided for the recombinant expression of dirigent proteins and/or pinoresinol/lariciresinol reductases.

Synthesis and characterization of recombinant abductin-based proteins.

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Su, Renay S-C; Renner, Julie N; Liu, Julie C

2013-12-09

Recombinant proteins are promising tools for tissue engineering and drug delivery applications. Protein-based biomaterials have several advantages over natural and synthetic polymers, including precise control over amino acid composition and molecular weight, modular swapping of functional domains, and tunable mechanical and physical properties. In this work, we describe recombinant proteins based on abductin, an elastomeric protein that is found in the inner hinge of bivalves and functions as a coil spring to keep shells open. We illustrate, for the first time, the design, cloning, expression, and purification of a recombinant protein based on consensus abductin sequences derived from Argopecten irradians . The molecular weight of the protein was confirmed by mass spectrometry, and the protein was 94% pure. Circular dichroism studies showed that the dominant structures of abductin-based proteins were polyproline II helix structures in aqueous solution and type II β-turns in trifluoroethanol. Dynamic light scattering studies illustrated that the abductin-based proteins exhibit reversible upper critical solution temperature behavior and irreversible aggregation behavior at high temperatures. A LIVE/DEAD assay revealed that human umbilical vein endothelial cells had a viability of 98 ± 4% after being cultured for two days on the abductin-based protein. Initial cell spreading on the abductin-based protein was similar to that on bovine serum albumin. These studies thus demonstrate the potential of abductin-based proteins in tissue engineering and drug delivery applications due to the cytocompatibility and its response to temperature.

Localization of S-100 proteins in the testis and epididymis of poultry and rabbits

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Abd-Elmaksoud, Ahmed; Marei, Hany E. S.

2014-01-01

The present investigation was conducted to demonstrate S-100 protein in the testis and epididymis of adult chickens, Sudani ducks, pigeons, and rabbits. This study may represent the first indication for the presence of S-100 in the male reproductive organs of these species and might therefore serve as a milestone for further reports. In the testis of chickens, pigeons and rabbits, intense S-100 was seen in Sertoli cells. S-100 was also seen in the endothelial lining of blood vessels in rabbit testis. On the contrary, no S-100 reaction was detected in the Sertoli cells of Sudani ducks. In epididymis, the localization of S-100 had varied according to species studied; it was seen in the basal cells (BC) of epididymal duct in duck, non-ciliated cells of the distal efferent ductules in pigeons and ciliated cells of the efferent ductules and BC of rabbit epididymis. Conversely, S-100 specific staining was not detected in the epithelial lining of the rooster and pigeon epididymal duct as well as the principal cells of the rabbit epididymis. In conclusion, the distribution of the S-100 proteins in the testis and epididymis might point out to its roles in the male reproduction. PMID:25276477

Structural and functional diversification in the teleost S100 family of calcium-binding proteins

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Korsching Sigrun I

2008-02-01

Full Text Available Abstract Background Among the EF-Hand calcium-binding proteins the subgroup of S100 proteins constitute a large family with numerous and diverse functions in calcium-mediated signaling. The evolutionary origin of this family is still uncertain and most studies have examined mammalian family members. Results We have performed an extensive search in several teleost genomes to establish the s100 gene family in fish. We report that the teleost S100 repertoire comprises fourteen different subfamilies which show remarkable similarity across six divergent teleost species. Individual species feature distinctive subsets of thirteen to fourteen genes that result from local gene duplications and gene losses. Eight of the fourteen S100 subfamilies are unique for teleosts, while six are shared with mammalian species and three of those even with cartilaginous fish. Several S100 family members are found in jawless fish already, but none of them are clear orthologs of cartilaginous or bony fish s100 genes. All teleost s100 genes show the expected structural features and are subject to strong negative selection. Many aspects of the genomic arrangement and location of mammalian s100 genes are retained in the teleost s100 gene family, including a completely conserved intron/exon border between the two EF hands. Zebrafish s100 genes exhibit highly specific and characteristic expression patterns, showing both redundancy and divergence in their cellular expression. In larval tissue expression is often restricted to specific cell types like keratinocytes, hair cells, ionocytes and olfactory receptor neurons as demonstrated by in situ hybridization. Conclusion The origin of the S100 family predates at least the segregation of jawed from jawless fish and some extant family members predate the divergence of bony from cartilaginous fish. Despite a complex pattern of gene gains and losses the total repertoire size is remarkably constant between species. On the expression

Metastasis-inducing S100A4 protein is associated with the disease activity of rheumatoid arthritis

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Oslejsková, Lucie; Grigorian, Mariam; Hulejová, Hana

2009-01-01

To evaluate the association between metastasis-inducing protein S100A4 and disease activity in patients with RA, and to demonstrate the effect of TNF-alpha blocking therapy on plasma levels of S100A4 in these patients.......To evaluate the association between metastasis-inducing protein S100A4 and disease activity in patients with RA, and to demonstrate the effect of TNF-alpha blocking therapy on plasma levels of S100A4 in these patients....

Plastoglobules: a new address for targeting recombinant proteins in the chloroplast

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Kessler Felix

2007-01-01

Full Text Available Abstract Background The potential of transgenic plants for cost-effective production of pharmaceutical molecules is now becoming apparent. Plants have the advantage over established fermentation systems (bacterial, yeast or animal cell cultures to circumvent the risk of pathogen contamination, to be amenable to large scaling up and to necessitate only established farming procedures. Chloroplasts have proven a useful cellular compartment for protein accumulation owing to their large size and number, as well as the possibility for organellar transformation. They therefore represent the targeting destination of choice for recombinant proteins in leaf crops such as tobacco. Extraction and purification of recombinant proteins from leaf material contribute to a large extent to the production costs. Developing new strategies facilitating these processes is therefore necessary. Results Here, we evaluated plastoglobule lipoprotein particles as a new subchloroplastic destination for recombinant proteins. The yellow fluorescent protein as a trackable cargo was targeted to plastoglobules when fused to plastoglobulin 34 (PGL34 as the carrier. Similar to adipocyte differentiation related protein (ADRP in animal cells, most of the protein sequence of PGL34 was necessary for targeting to lipid bodies. The recombinant protein was efficiently enriched in plastoglobules isolated by simple flotation centrifugation. The viability of plants overproducing the recombinant protein was not affected, indicating that plastoglobule targeting did not significantly impair photosynthesis or sugar metabolism. Conclusion Our data identify plastoglobules as a new targeting destination for recombinant protein in leaf crops. The wide-spread presence of plastoglobules and plastoglobulins in crop species promises applications comparable to those of transgenic oilbody-oleosin technology in molecular farming.

Viral vectors for production of recombinant proteins in plants.

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Lico, Chiara; Chen, Qiang; Santi, Luca

2008-08-01

Global demand for recombinant proteins has steadily accelerated for the last 20 years. These recombinant proteins have a wide range of important applications, including vaccines and therapeutics for human and animal health, industrial enzymes, new materials and components of novel nano-particles for various applications. The majority of recombinant proteins are produced by traditional biological "factories," that is, predominantly mammalian and microbial cell cultures along with yeast and insect cells. However, these traditional technologies cannot satisfy the increasing market demand due to prohibitive capital investment requirements. During the last two decades, plants have been under intensive investigation to provide an alternative system for cost-effective, highly scalable, and safe production of recombinant proteins. Although the genetic engineering of plant viral vectors for heterologous gene expression can be dated back to the early 1980s, recent understanding of plant virology and technical progress in molecular biology have allowed for significant improvements and fine tuning of these vectors. These breakthroughs enable the flourishing of a variety of new viral-based expression systems and their wide application by academic and industry groups. In this review, we describe the principal plant viral-based production strategies and the latest plant viral expression systems, with a particular focus on the variety of proteins produced and their applications. We will summarize the recent progress in the downstream processing of plant materials for efficient extraction and purification of recombinant proteins. (c) 2008 Wiley-Liss, Inc.

Expression, Delivery and Function of Insecticidal Proteins Expressed by Recombinant Baculoviruses

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Kroemer, Jeremy A.; Bonning, Bryony C.; Harrison, Robert L.

2015-01-01

Since the development of methods for inserting and expressing genes in baculoviruses, a line of research has focused on developing recombinant baculoviruses that express insecticidal peptides and proteins. These recombinant viruses have been engineered with the goal of improving their pesticidal potential by shortening the time required for infection to kill or incapacitate insect pests and reducing the quantity of crop damage as a consequence. A wide variety of neurotoxic peptides, proteins that regulate insect physiology, degradative enzymes, and other potentially insecticidal proteins have been evaluated for their capacity to reduce the survival time of baculovirus-infected lepidopteran host larvae. Researchers have investigated the factors involved in the efficient expression and delivery of baculovirus-encoded insecticidal peptides and proteins, with much effort dedicated to identifying ideal promoters for driving transcription and signal peptides that mediate secretion of the expressed target protein. Other factors, particularly translational efficiency of transcripts derived from recombinant insecticidal genes and post-translational folding and processing of insecticidal proteins, remain relatively unexplored. The discovery of RNA interference as a gene-specific regulation mechanism offers a new approach for improvement of baculovirus biopesticidal efficacy through genetic modification. PMID:25609310

Expression of Hepatitis C Virus Core and E2 antigenic recombinant proteins and their use for development of diagnostic assays.

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Ali, Amjad; Nisar, Muhammad; Idrees, Muhammad; Rafique, Shazia; Iqbal, Muhammad

2015-05-01

Early diagnosis of HCV infection is based on detection of antibodies against HCV proteins using recombinant viral antigens. The present study was designed to select, clone and express the antigenic regions of Core and E2 genes from local HCV-3a genotype and to utilize the antigenic recombinant proteins (Core & E2) to develop highly sensitive, specific and economical diagnostic assays for detection of HCV infection. The antigenic sites were determined within Core and E2 genes and were then cloned in pET-28a expression vector. The right orientation of the desired inserted fragments of Core and E2 were confirmed via sequencing prior to expression and were then transformed in BL21 (DE3) pLysS strains of E. coli and induced with 0.5mM Isopropyl-b-D-thiogalactopyranoside (IPTG) for the production of antigenic recombinant proteins. The produced truncated antigens were then purified by Nickel affinity chromatography and were confirmed by western blotting, immunoblotting and enzyme-linked immunosorbent assay (ELISA). The expressed Core and E2 recombinant antigens were used to develop immunoblotting assay for the detection of anti-HCV antibodies in sera. With immunoblotting, a total of 93-HCV infected sera and 35-HCV negative individuals were tested for the presence of anti-HCV antibodies to the Core and E2 antigens. Recombinant antigen showed 100% reactivity against HCV infected sera, with no cross reactivity against HCV-negative sera. The immunoblot assay mixture of recombinant antigens (Core+E2) showed a strong reaction intensity in the test area (TA) as compared to the individual truncated Core and E2 recombinant antigens. In the in-house ELISA assay, mixed Core and E2 recombinant antigens showed 100% reactivity against a standardized panel of 150-HCV-positive sera and non reactivity against a standardized panel of 150 HCV-negative sera while also being non reactive to sera positive for other viral infections. The antigenic recombinant antigens also were tested for the

Calcium dependent formation of tubular assemblies by recombinant S-layer proteins in vivo and in vitro

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Korkmaz, Nuriye; Ostermann, Kai; Rödel, Gerhard

2011-03-01

Surface layer proteins have the appealing property to self-assemble in nanosized arrays in solution and on solid substrates. In this work, we characterize the formation of assembly structures of the recombinant surface layer protein SbsC of Geobacillus stearothermophilus ATTC 12980, which was tagged with enhanced green fluorescent protein and expressed in the yeast Saccharomyces cerevisiae. The tubular structures formed by the protein in vivo are retained upon bursting the cells by osmotic shock; however, their average length is decreased. During dialysis, monomers obtained by treatment with chaotropic chemicals recrystallize again to form tube-like structures. This process is strictly dependent on calcium (Ca2 + ) ions, with an optimal concentration of 10 mM. Further increase of the Ca2 + concentration results in multiple non-productive nucleation points. We further show that the lengths of the S-layer assemblies increase with time and can be controlled by pH. After 48 h, the average length at pH 9.0 is 4.13 µm compared to 2.69 µm at pH 5.5. Successful chemical deposition of platinum indicates the potential of recrystallized mSbsC-eGFP structures for nanobiotechnological applications.

Insulin Stimulates S100B Secretion and These Proteins Antagonistically Modulate Brain Glucose Metabolism.

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Wartchow, Krista Minéia; Tramontina, Ana Carolina; de Souza, Daniela F; Biasibetti, Regina; Bobermin, Larissa D; Gonçalves, Carlos-Alberto

2016-06-01

Brain metabolism is highly dependent on glucose, which is derived from the blood circulation and metabolized by the astrocytes and other neural cells via several pathways. Glucose uptake in the brain does not involve insulin-dependent glucose transporters; however, this hormone affects the glucose influx to the brain. Changes in cerebrospinal fluid levels of S100B (an astrocyte-derived protein) have been associated with alterations in glucose metabolism; however, there is no evidence whether insulin modulates glucose metabolism and S100B secretion. Herein, we investigated the effect of S100B on glucose metabolism, measuring D-(3)H-glucose incorporation in two preparations, C6 glioma cells and acute hippocampal slices, and we also investigated the effect of insulin on S100B secretion. Our results showed that: (a) S100B at physiological levels decreases glucose uptake, through the multiligand receptor RAGE and mitogen-activated protein kinase/ERK signaling, and (b) insulin stimulated S100B secretion via PI3K signaling. Our findings indicate the existence of insulin-S100B modulation of glucose utilization in the brain tissue, and may improve our understanding of glucose metabolism in several conditions such as ketosis, streptozotocin-induced dementia and pharmacological exposure to antipsychotics, situations that lead to changes in insulin signaling and extracellular levels of S100B.

Diagnostic potential of recombinant scFv antibodies generated against hemagglutinin protein of influenza A virus

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Roopali eRajput

2015-09-01

Full Text Available Human influenza A viruses have been the cause of enormous socio-economic losses worldwide. In order to combat such a notorious pathogen, hemagglutinin protein (HA has been a preferred target for generation of neutralizing-antibodies, as potent therapeutic/ diagnostic agents. In the present study, recombinant anti-HA single chain variable fragment (scFv antibodies were constructed using the phage display technology to aid in diagnosis and treatment of human influenza A virus infections. Spleen cells of mice hyper-immunized with A/New Caledonia/20/99 (H1N1 virus were used as the source for recombinant antibody (rAb production. The antigen-binding phages were quantified after 6 rounds of bio-panning against A/New Caledonia/20/99 (H1N1, A/California/07/2009 (H1N1-like, or A/Udorn/307/72(H3N2 viruses. The phage yield was maximum for the A/New Caledonia/20/99 (H1N1, however, considerable cross-reactivity was observed for the other virus strains as well. The HA-specific polyclonal rAb preparation was subjected to selection of single clones for identification of high reactive relatively conserved epitopes. The high affinity rAbs were tested against certain known conserved HA epitopes by peptide ELISA. Three recombinant mAbs showed reactivity with both the H1N1 strains and one (C5 showed binding with all the three viral strains. The C5 antibody was thus used for development of an ELISA test for diagnosis of influenza virus infection. Based on the sample size in the current analysis, the ELISA test demonstrated 83.9% sensitivity and 100% specificity. Thus, the ELISA, developed in our study, may prove as a cheaper alternative to the presently used real time RT-PCR test for detection of human influenza A viruses in clinical specimens, which will be beneficial, especially in the developing countries. Since, the two antibodies identified in this study are reactive to conserved HA epitopes; these may prove as potential therapeutic agents as well.

Evaluation of recombinant multi-epitope proteins for diagnosis of goat schistosomiasis by enzyme-linked immunosorbent assay.

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Lv, Chao; Hong, Yang; Fu, Zhiqiang; Lu, Ke; Cao, Xiaodan; Wang, Tao; Zhu, Chuangang; Li, Hao; Xu, Rui; Jia, Bingguang; Han, Qian; Dou, Xuefeng; Shen, Yuanxi; Zhang, Zuhang; Zai, Jinli; Feng, Jintao; Lin, Jiaojiao

2016-03-09

Schistosomiasis is a huge threat to human and animal health. Apart from bovines, goats play an important role in the transmission of schistosomiasis in some endemic areas of China. An accessible, quality-assured goat schistosomiasis diagnostic technique is needed. Recently, our laboratory identified two recombinant diagnostic antigens, SjPGM and SjRAD23 via an immuno-proteomic method. The application of these two recombinant antigens to develop a higher sensitivity and specificity technique for the sheep schistosomiasis diagnosis is urgently needed. Epitopes of SjPGM and SjRAD23 were predicted and three polypeptides, two from SjRAD23 and one from SjPGM, were selected. Recombinant plasmids containing two to three DNA sequences encoding predicted polypeptides or large hydrophilic region of Sj23 (LHD-Sj23) were constructed and expressed. Eight recombinant schistosome antigens including four multi-epitope proteins and four recombinant single-molecule antigens as well as SEA, were assessed by ELISA in 91 sera from schistosome-infected goats, 44 sera from non-infected goats, 37 sera from Orientobilharzia-infected goats, and 12 from Haemonchus contortus-infected goats. ELISA tests showed that three multi-epitope proteins had higher sensitivity than the four single-molecule antigens (rSjRAD23, rSjPGM, rBSjRAD23-1, rBSj23) and the multi-epitope protein rBSjPGM-BSjRAD23-1-BSj23 had the highest sensitivity (97.8 %, 89/91) and maintained good specificity (100 %, 44/44) as well as low cross-reactivity with haemonchosis (8.33 %, 3/12) and orientobilharziasis (13.51 %, 5/37) in the diagnosis of goat schistosomiasis. In contrast, when SEA was applied as a diagnosis antigen, it had 100 % (91/91) sensitivity, 75 % (33/44) specificity, 25 and 83.78 % cross-reactivity with haemonchosis (3/12) and orientobilharziasis (31/37), respectively. The application of recombinant multi-epitope proteins may increase the sensitivity of diagnosis technique and retain high specificity of single

Correlation between Amitriptyline-Induced Cardiotoxic Effects and Cardiac S100b Protein in Isolated Rat Hearts

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Nil Hocaoğlu

2016-12-01

Full Text Available Background: Amitriptyline is an important cause of mortality due to its cardiovascular toxicity. Aims: To investigate the changes in levels of cardiac S100b protein on amitriptyline-induced cardiotoxicity and also to examine the correlation between amitriptyline-induced cardiotoxic effects and cardiac S100b protein in an isolated rat heart model. Study Design: Animal experimentation, isolated heart model. Methods: After a stabilization period, isolated hearts were randomized to two groups (n=5 and n=7. In the control group, isolated hearts were subjected to an infusion of 5% dextrose for 60 minutes. In the amitriptyline group, 5.5×10-5 M amitriptyline was infused for 60 minutes to achieve amitriptyline toxicity. After the infusion period, heart tissues were removed for histological examination. Results: In comparison to control treatment, amitriptyline infusion decreased left ventricular developed pressure (LVDP, dp/dtmax and heart rate (HR and significantly prolonged QRS duration (p<0.05. The semiquantitative scores for S100b protein levels in amitriptyline-infused hearts were higher than in the control group (p<0.01. At the end of the experiment, in the amitriptyline-infused group, significant correlations were found between LVDP and S100b protein scores (r=-0.807, p=0.003 and between QRS duration and S100b protein scores (r=0.859, p=0.001. Conclusion: Our results indicate that the S100b protein may be a helpful indicator or biomarker in studying the cardiotoxic effects of amitriptyline.

Immunohistochemical localization of anterior pituitary hormones in S-100 protein-positive cells in the rat pituitary gland.

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Kikuchi, Motoshi; Yatabe, Megumi; Tando, Yukiko; Yashiro, Takashi

2011-09-01

In the anterior and intermediate lobes of the rat pituitary gland, non-hormone-producing cells that express S-100 protein coexist with various types of hormone-producing cells and are believed to function as phagocytes, supporting and paracrine-controlling cells of hormone-producing cells and stem cells, among other functions; however, their cytological characteristics are not yet fully understood. Using a transgenic rat that expresses green fluorescent protein under the promoter of the S100β protein gene, we immunohistochemically detected expression of the luteinizing hormone, thyroid-stimulating hormone, prolactin, growth hormone and proopiomelanocortin by S-100 protein-positive cells located between clusters of hormone-producing cells in the intermediate lobe. These findings lend support to the hypothesis that S-100 protein-positive cells are capable of differentiating into hormone-producing cells in the adult rat pituitary gland.

Production of recombinant proteins from Plasmodium falciparum in Escherichia coli.

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Guerra, Ángela Patricia; Calvo, Eliana Patricia; Wasserman, Moisés; Chaparro-Olaya, Jacqueline

2016-02-23

The production of recombinant proteins is essential for the characterization and functional study of proteins from Plasmodium falciparum. However, the proteins of P. falciparum are among the most challenging to express, and when expression is achieved, the recombinant proteins usually fold incorrectly and lead to the formation of inclusion bodies.  To obtain and purify four recombinant proteins and to use them as antigens to produce polyclonal antibodies. The production efficiency and solubility were evaluated as the proteins were expressed in two genetically modified strains of Escherichia coli to favor the production of heterologous proteins (BL21-CodonPlus (DE3)-RIL and BL21-pG-KJE8).  The four recombinant P. falciparum proteins corresponding to partial sequences of PfMyoA (Myosin A) and PfGAP50 (gliding associated protein 50), and the complete sequences of PfMTIP (myosin tail interacting protein) and PfGAP45 (gliding associated protein 45), were produced as glutathione S-transferase-fusion proteins, purified and used for immunizing mice.  The protein expression was much more efficient in BL21-CodonPlus, the strain that contains tRNAs that are rare in wild-type E. coli, compared to the expression in BL21-pG-KJE8. In spite of the fact that BL21-pG-KJE8 overexpresses chaperones, this strain did not minimize the formation of inclusion bodies.  The use of genetically modified strains of E. coli was essential to achieve high expression levels of the four evaluated P. falciparum proteins and lead to improved solubility of two of them. The approach used here allowed us to obtain and purify four P. falciparum proteins in enough quantity to produce polyclonal antibodies in mice, and a fair amount of two pure and soluble recombinant proteins for future assays.

In vivo production of recombinant proteins using occluded recombinant AcMNPV-derived baculovirus vectors.

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Guijarro-Pardo, Eva; Gómez-Sebastián, Silvia; Escribano, José M

2017-12-01

Trichoplusia ni insect larvae infected with vectors derived from the Autographa californica multiple nucleopolyhedrovirus (AcMNPV), are an excellent alternative to insect cells cultured in conventional bioreactors to produce recombinant proteins because productivity and cost-efficiency reasons. However, there is still a lot of work to do to reduce the manual procedures commonly required in this production platform that limit its scalability. To increase the scalability of this platform technology, a current bottleneck to be circumvented in the future is the need of injection for the inoculation of larvae with polyhedrin negative baculovirus vectors (Polh-) because of the lack of oral infectivity of these viruses, which are commonly used for production in insect cell cultures. In this work we have developed a straightforward alternative to obtain orally infective vectors derived from AcMNPV and expressing recombinant proteins that can be administered to the insect larvae (Trichoplusia ni) by feeding, formulated in the insect diet. The approach developed was based on the use of a recombinant polyhedrin protein expressed by a recombinant vector (Polh+), able to co-occlude any recombinant Polh- baculovirus vector expressing a recombinant protein. A second alternative was developed by the generation of a dual vector co-expressing the recombinant polyhedrin protein and the foreign gene of interest to obtain the occluded viruses. Additionally, by the incorporation of a reporter gene into the helper Polh+ vector, it was possible the follow-up visualization of the co-occluded viruses infection in insect larvae and will help to homogenize infection conditions. By using these methodologies, the production of recombinant proteins in per os infected larvae, without manual infection procedures, was very similar in yield to that obtained by manual injection of recombinant Polh- AcMNPV-based vectors expressing the same proteins. However, further analyses will be required for a

Demonstration of S-100 protein in sustentacular cells of phaeochromocytomas and paragangliomas

DEFF Research Database (Denmark)

Schroder, H D; Johannsen, L

1986-01-01

to the sustentacular cells of normal paraganglia and adrenal medulla were found in all paragangliomas and in the benign and aggressively growing phaeochromocytomas. In the two malignant tumours no positive reaction was demonstrated. In one tumour the sustentacular cells were shown to contain glial fibrillary acidic......Eighteen phaeochromocytomas, including both sporadic and familial cases, four cervical paragangliomas, two jugular paragangliomas, and one abdominal paraganglioma were examined immunohistochemically for the presence of S-100 protein. Positive staining in cells morphologically similar...... protein further supporting their Schwann cell relationship. The number of S-100 positive cells varied considerably. They demonstrated a spindle celled or elongated configuration with long slender processes. The nature of the sustentacular cell proliferation, neoplastic versus reactive, is discussed....

Production and characterization of monoclonal antibodies that discriminate among individual S100 polypeptides

International Nuclear Information System (INIS)

Van Eldik, L.J.

1984-01-01

The term S100 refers to a heterogeneous fraction of low molecular weight, acidic, calcium binding proteins. The S100 fraction is a mixture of polypeptides, only some of which have been isolated and characterized. The amino acid sequences of two S100 proteins from bovine brain, S100α and S100β, have been determined. The physiological functions of the S100 proteins are not known. Although assay of immunoreactive S100 has been used clinically to screen tumors of neural origin, as an index of cell injury in various disorders, and as an index of malignancy, most of the antisera used in previous studies react with more than one protein in the S100 fraction. Even the currently available monoclonal antibodies against S100 (2-4) do not appear to measure the individual S100α and S100β components. In order to unequivocally interpret studies on the localization of S100 and its potential alterations in various disease states, and on the validity of S100 immunoreactivity as a diagnostic tool for tumor diagnosis, it would be useful to have antibodies that discriminate among the individual S100 components. The authors report here the production of monoclonal antibodies that appear to be specific for S100β

Expression and Evaluation of Recombinant Plasmodium knowlesi Merozoite Surface Protein-3 (MSP-3 for Detection of Human Malaria.

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Jeremy Ryan De Silva

Full Text Available Malaria remains a major health threat in many parts of the globe and causes high mortality and morbidity with 214 million cases of malaria occurring globally in 2015. Recent studies have outlined potential diagnostic markers and vaccine candidates one of which is the merozoite surface protein (MSP-3. In this study, novel recombinant Plasmodium knowlesi MSP-3 was cloned, expressed and purified in an Escherichia coli system. Subsequently, the recombinant protein was evaluated for its sensitivity and specificity. The recombinant pkMSP-3 protein reacted with sera from patients with P. knowlesi infection in both Western blot (61% and ELISA (100%. Specificity-wise, pkMSP-3 did not react with healthy donor sera in either assay and only reacted with a few non-malarial parasitic patient sera in the ELISA assay (3 of 49. In conclusion, sensitivity and specificity of pkMSP-3 was found to be high in the ELISA and Western Blot assay and thus utilising both assays in tandem would provide the best sero-diagnostic result for P. knowlesi infection.

Immunizing Patients With Metastatic Melanoma Using Recombinant Adenoviruses Encoding MART-1 or gp100 Melanoma Antigens

Science.gov (United States)

Rosenberg, Steven A.; Zhai, Yifan; Yang, James C.; Schwartzentruber, Douglas J.; Hwu, Patrick; Marincola, Francesco M.; Topalian, Suzanne L.; Restifo, Nicholas P.; Seipp, Claudia A.; Einhorn, Jan H.; Roberts, Bruce; White, Donald E.

2008-01-01

Background: The characterization of the genes encoding melanoma-associated antigens MART-1 or gp100, recognized by T cells, has opened new possibilities for the development of immunization strategies for patients with metastatic melanoma. With the use of recombinant adenoviruses expressing either MART-1 or gp100 to immunize patients with metastatic melanoma, we evaluated the safety, immunologic, and potential therapeutic aspects of these immunizations. Methods: In phase I studies, 54 patients received escalating doses (between 107 and 1011 plaque-forming units) of recombinant adenovirus encoding either MART-1 or gp100 melanoma antigen administered either alone or followed by the administration of interleukin 2 (IL-2). The immunologic impact of these immunizations on the development of cellular and antibody reactivity was assayed. Results: Recombinant adenoviruses expressing MART-1 or gp100 were safely administered. One of 16 patients with metastatic melanoma receiving the recombinant adenovirus MART-1 alone experienced a complete response. Other patients achieved objective responses, but they had received IL-2 along with an adenovirus, and their responses could be attributed to the cytokine. Immunologic assays showed no consistent immunization to the MART-1 or gp100 transgenes expressed by the recombinant adenoviruses. High levels of neutralizing antibody were found in the pretreatment sera of the patients. Conclusions: High doses of recombinant adenoviruses could be safely administered to cancer patients. High levels of neutralizing antibody present in patients' sera prior to treatment may have impaired the ability of these viruses to immunize patients against melanoma antigens. PMID:9862627

Expression of S100 protein and protective effect of arundic acid on the rat brain in chronic cerebral hypoperfusion.

Science.gov (United States)

Ohtani, Ryo; Tomimoto, Hidekazu; Wakita, Hideaki; Kitaguchi, Hiroshi; Nakaji, Kayoko; Takahashi, Ryosuke

2007-03-02

S100 protein is expressed primarily by astroglia in the brain, and accumulates in and around the ischemic lesions. Arundic acid, a novel astroglia-modulating agent, is neuroprotective in acute cerebral infarction, whereas the protective effects remain unknown during chronic cerebral hypoperfusion. Rats undergoing chronic cerebral hypoperfusion were subjected to a bilateral ligation of the common carotid arteries, and were allowed to survive for 3, 7 and 14 days. The animals received a daily intraperitoneal injection of 5.0, 10.0 or 20.0 mg/kg of arundic acid, or vehicle, for 14 days. Alternatively, other groups of rats received a delayed intraperitoneal injection of 20.0 mg/kg of arundic acid or vehicle, which started from 1, 3 or 7 days after ligation and continued to 14 days. The degree of white matter (WM) lesions and the numerical density of S100 protein-immunoreactive astroglia were estimated. In the WM of rats with vehicle injections, the number of S100 protein-immunoreactive astroglia increased significantly after chronic cerebral hypoperfusion as compared to the sham-operation. A dosage of 10.0 and 20.0 mg/kg of arundic acid suppressed the numerical increase in S100 protein-immunoreactive astroglia and the WM lesions. These pathological changes were suppressed with delayed treatment up to 7 days in terms of astroglial activation, and up to 3 days in terms of the WM lesions. The protective effects of arundic acid against WM lesions were demonstrated in a dose-dependent manner, and even after postischemic treatments. These results suggest the potential usefulness of arundic acid in the treatment of cerebrovascular WM lesions.

Evaluation of recombinant porin (rOmp2a) protein as a potential antigen candidate for serodiagnosis of Human Brucellosis.

Science.gov (United States)

Pathak, Prachi; Kumar, Ashu; Thavaselvam, Duraipandian

2017-07-11

Brucellosis is an important zoonotic disease caused by different Brucella species and human brucellosis is commonly prevalent in different states of India. Among various Brucella species, B. melitensis is most pathogenic to human and included as category B biothreat which can cause infection through aerosol, cut, wounds in skin and contact with infected animals. The diagnosis of human brucellosis is very important for proper treatment and management of disease as there is no vaccine available for human use. The present study was designed to clone, express and purify immunodominant recombinant omp2a (rOmp2a) porin protein of B. melitensis and to evaluate this new antigen candidate for specific serodiagnosis of human brucellosis by highly sensitive iELISA (indirect enzyme linked immunosorbent assay). Omp2a gene of B. melitensis 16 M strain was cloned and expressed in pET-SUMO expression system. The recombinant protein was purified under denaturing conditions using 8 M urea. The purified recombinant protein was confirmed by western blotting by reacting with anti-HIS antibody. The sero-reactivity of the recombinant protein was also checked by reacting with antisera of experimentally infected mice with B. melitensis 16 M at different time points. Serodiagnostic potential of recombinant porin antigen was tested against 185 clinical serum samples collected from regions endemic to brucellosis in southern part of India by iELISA. The samples were grouped into five groups. Group 1 contained cultured confirmed positive serum samples of brucellosis (n = 15), group 2 contained sera samples from positive cases of brucellosis previously tested by conventional methods of RBPT (n = 28) and STAT (n = 26), group 3 contained sera samples negative by RBPT(n = 36) and STAT (n = 32), group 4 contained sera samples of other febrile illness and PUO case (n = 35) and group 5 contained confirmed negative sera samples from healthy donors (n = 23). The rOmp2a was found to be

Os possíveis papéis da S100B na esquizofrenia Potential roles of S100B in schizophrenia

Directory of Open Access Journals (Sweden)

Johann Steiner

2012-01-01

Full Text Available CONTEXTO: Evidências científicas do aumento da concentração da proteína S100B no sangue de pacientes esquizofrênicos são muito consistentes. No passado essa informação era principalmente considerada como reflexo da disfunção astroglial ou da barreira hematoencefálica. MÉTODOS: Pesquisa de publicações no PubMed até o dia 15 de junho de 2011 visando estabelecer potenciais ligações entre a proteína S100B e as hipóteses correntes da esquizofrenia. RESULTADOS: A S100B está potencialmente associada com as hipóteses dopaminérgica e glutamatérgica. O aumento da expressão de S100B tem sido detectado em astrócitos corticais em casos de esquizofrenia paranoide, enquanto se observa uma redução da expressão em oligodendrócitos na esquizofrenia residual, dando suporte à hipótese glial. Recentemente, a hipótese da neuroinflamação da esquizofrenia tem recebido atenção crescente. Nesse sentido, a S100B pode funcionar como uma citocina secretada por células gliais, linfócitos CD8+ e células NK, levando à ativação de monócitos e microglia. Além disso, a S100B apresenta propriedades do tipo adipocina e pode estar desregulada na esquizofrenia, devido a distúrbios da sinalização de insulina, levando ao aumento da liberação de S100B e ácidos graxos do tecido adiposo. CONCLUSÃO: A expressão de S100B em diferentes tipos celulares está envolvida em muitos processos regulatórios. Atualmente, não pode ser respondido qual mecanismo relacionado à esquizofrenia é o mais importante.BACKGROUND: Scientific evidence for increased S100B concentrations in the peripheral blood of acutely ill schizophrenia patients is consistent. In the past, this finding was mainly considered to reflect astroglial or blood-brain barrier dysfunction. METHODS: Using Entrez, PubMed was searched for articles published on or before June 15, 2011, including electronic early release publications, in order to determine other potential links between S

Os possíveis papéis da S100B na esquizofrenia Potential roles of S100B in schizophrenia

Directory of Open Access Journals (Sweden)

Johann Steiner

2013-01-01

Full Text Available CONTEXTO: Evidências científicas do aumento da concentração da proteína S100B no sangue de pacientes esquizofrênicos são muito consistentes. No passado essa informação era principalmente considerada como reflexo da disfunção astroglial ou da barreira hematoencefálica. MÉTODOS: Pesquisa de publicações no PubMed até o dia 15 de junho de 2011 visando estabelecer potenciais ligações entre a proteína S100B e as hipóteses correntes da esquizofrenia. RESULTADOS: A S100B está potencialmente associada com as hipóteses dopaminérgica e glutamatérgica. O aumento da expressão de S100B tem sido detectado em astrócitos corticais em casos de esquizofrenia paranoide, enquanto se observa uma redução da expressão em oligodendrócitos na esquizofrenia residual, dando suporte à hipótese glial. Recentemente, a hipótese da neuroinflamação da esquizofrenia tem recebido atenção crescente. Nesse sentido, a S100B pode funcionar como uma citocina secretada por células gliais, linfócitos CD8+ e células NK, levando à ativação de monócitos e microglia. Além disso, a S100B apresenta propriedades do tipo adipocina e pode estar desregulada na esquizofrenia, devido a distúrbios da sinalização de insulina, levando ao aumento da liberação de S100B e ácidos graxos do tecido adiposo. CONCLUSÃO: A expressão de S100B em diferentes tipos celulares está envolvida em muitos processos regulatórios. Atualmente, não pode ser respondido qual mecanismo relacionado à esquizofrenia é o mais importante.BACKGROUND: Scientific evidence for increased S100B concentrations in the peripheral blood of acutely ill schizophrenia patients is consistent. In the past, this finding was mainly considered to reflect astroglial or blood-brain barrier dysfunction. METHODS: Using Entrez, PubMed was searched for articles published on or before June 15, 2011, including electronic early release publications, in order to determine other potential links between S

Expression and purification of recombinant proteins in Escherichia coli tagged with the metal-binding protein CusF.

Science.gov (United States)

Cantu-Bustos, J Enrique; Vargas-Cortez, Teresa; Morones-Ramirez, Jose Ruben; Balderas-Renteria, Isaias; Galbraith, David W; McEvoy, Megan M; Zarate, Xristo

2016-05-01

Production of recombinant proteins in Escherichia coli has been improved considerably through the use of fusion proteins, because they increase protein solubility and facilitate purification via affinity chromatography. In this article, we propose the use of CusF as a new fusion partner for expression and purification of recombinant proteins in E. coli. Using a cell-free protein expression system, based on the E. coli S30 extract, Green Fluorescent Protein (GFP) was expressed with a series of different N-terminal tags, immobilized on self-assembled protein microarrays, and its fluorescence quantified. GFP tagged with CusF showed the highest fluorescence intensity, and this was greater than the intensities from corresponding GFP constructs that contained MBP or GST tags. Analysis of protein production in vivo showed that CusF produces large amounts of soluble protein with low levels of inclusion bodies. Furthermore, fusion proteins can be exported to the cellular periplasm, if CusF contains the signal sequence. Taking advantage of its ability to bind copper ions, recombinant proteins can be purified with readily available IMAC resins charged with this metal ion, producing pure proteins after purification and tag removal. We therefore recommend the use of CusF as a viable alternative to MBP or GST as a fusion protein/affinity tag for the production of soluble recombinant proteins in E. coli. Copyright © 2016 Elsevier Inc. All rights reserved.

Obtaining classical swine fever virus E2 recombinant protein and DNA-vaccine on the basis of one subunit

International Nuclear Information System (INIS)

Deryabin, O.; Deryabina, O.; Verbitskiy, P.; Kordyum, V.

2005-01-01

Three forms of E2 recombinant protein were expressed in E. coli. Swine sera obtained against different forms of the recombinant protein were cross-studied with indirect ELISA. Using individual proteins as an antigen, only 15% of sera against other forms of protein reacted positively, while 100% of heterologous sera showed positive reaction with fused protein. Challenge experiments showed the existence of protective action only from the individual protein. Specificity and activity of sera obtained from the animals after control challenge was confirmed in a blocking variant of ELISA. Genetic construction used a eukaryotic vector that contained the E2 protein gene. Immunization of mice with the resulting DNA induced synthesis of specific antibodies, the titre of which increased considerably after additional single immunization with the E2 recombinant protein, expressed in E. coli. This demonstrated the effectiveness of animal priming by DNA vaccine, and the possibility of using the E2 recombinant protein in E. coli for booster vaccination. (author)

Effect of calcium-binding protein S100A8 expression on early phase of radiation pulmonary fibrosis

International Nuclear Information System (INIS)

Rao Yalan; Li Ming; Cong Yue; Li Fengsheng; Chen Xiaohua; Dong Bo; Zhang Junquan; Gao Ling; Mao Bingzhi

2008-01-01

The study explores the expression and effect of calcium-binding protein S100A8 on early phase of radiation pulmonary fibrosis via in vivo and in vitro experiments. In vivo experiment, the thoracic regions of rats were irradiated under 20Gy 60 Co γ-rays to establish radiation pulmonary fibrosis. After irradiation, the lung specimens of the sacrificed rats were separately harvested by the ends of the first, second, and fourth weeks respectively. The protein expression of S100A8 was tested through immunohistochemistry, the mRNA expression of S100A8 and its heterodimeric S100A9 were investigated by RT-PCR method. In vitro experiment, RT-PCR method was also applied to measure the mRNA expression of S100A8 in mouse macrophage cell line RAW264.7 after γ-rays irradiation and/or lipopolysaccharide (LPS). It shows that the protein expression of S100A8 was increased in the plasma of lung macrophages samples and the mRNA expression of S100A8 and S100A9 was also increased in the lung tissue samples in four weeks after irradiation in vivo experiment. And in vitro experiment it shows that the cooperation between γ-rays and LPS can increase the mRNA expression of S100A8 in RAW264.7. These phenomena suggest that S100A8 can exert the chemotactic activity, participate in the inflammatory response, and influence the establishment of radiation pulmonary fibrosis. (authors)

Interplay between Trx-1 and S100P promotes colorectal cancer cell epithelial-mesenchymal transition by up-regulating S100A4 through AKT activation.

Science.gov (United States)

Zuo, Zhigui; Zhang, Peili; Lin, Feiyan; Shang, Wenjing; Bi, Ruichun; Lu, Fengying; Wu, Jianbo; Jiang, Lei

2018-04-01

We previously reported a novel positive feedback loop between thioredoxin-1 (Trx-1) and S100P, which promotes the invasion and metastasis of colorectal cancer (CRC). However, the underlying molecular mechanisms remain poorly understood. In this study, we examined the roles of Trx-1 and S100P in CRC epithelial-to-mesenchymal transition (EMT) and their underlying mechanisms. We observed that knockdown of Trx-1 or S100P in SW620 cells inhibited EMT, whereas overexpression of Trx-1 or S100P in SW480 cells promoted EMT. Importantly, S100A4 and the phosphorylation of AKT were identified as potential downstream targets of Trx-1 and S100P in CRC cells. Silencing S100A4 or inhibition of AKT phosphorylation eliminated S100P- or Trx-1-mediated CRC cell EMT, migration and invasion. Moreover, inhibition of AKT activity reversed S100P- or Trx-1-induced S100A4 expression. The expression of S100A4 was higher in human CRC tissues compared with their normal counterpart tissues and was significantly correlated with lymph node metastasis and poor survival. The overexpression of S100A4 protein was also positively correlated with S100P or Trx-1 protein overexpression in our cohort of CRC tissues. In addition, overexpression of S100P reversed the Trx-1 knockdown-induced inhibition of S100A4 expression, EMT and migration and invasion in SW620 cells. The data suggest that interplay between Trx-1 and S100P promoted CRC EMT as well as migration and invasion by up-regulating S100A4 through AKT activation, thus providing further potential therapeutic targets for suppressing the EMT in metastatic CRC. © 2018 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Oral Administration of Recombinant Saccharomyces boulardii Expressing Ovalbumin-CPE Fusion Protein Induces Antibody Response in Mice

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Ghasem Bagherpour

2018-04-01

Full Text Available Saccharomyces boulardii, a subspecies of Saccharomyces cerevisiae, is a well-known eukaryotic probiotic with many benefits for human health. In the present study, a recombinant strain of S. boulardii was prepared to use as a potential oral vaccine delivery vehicle. In this sense, a ura3 auxotroph strain of S. boulardii CNCM I-745 (known as S. cerevisiae HANSEN CBS 5926, Yomogi® was generated using CRISPR/Cas9 methodology. Then a gene construct encoding a highly immunogenic protein, ovalbumin (OVA, was prepared and transformed into the ura3- S. boulardii. To facilitate the transport of the recombinant immunogen across the intestinal barrier, a claudin-targeting sequence from Clostridium perfringens enterotoxin (CPE was added to the C-terminus of the expression cassette. The recombinant S. boulardii strain expressing the OVA-CPE fusion protein was then administered orally to a group of mice, and serum IgG and fecal IgA levels were evaluated by ELISA. Our results demonstrated that anti-OVA IgG in serum significantly increased in test group (P < 0.001 compared to control groups (receiving wild type S. boulardii or PBS, and the fecal IgA titer was significantly higher in test group (P < 0.05 than control groups. In parallel, a recombinant S. boulardii strain expressing the similar construct lacking C-terminal CPE was also administered orally. The result showed an increased level of serum IgG in group receiving yeasts expressing the CPE negative construct compared to control groups; however, the fecal IgA levels did not increase significantly. In conclusion, our findings indicated that the yeast S. boulardii, as a delivery vehicle with possible immunomodulatory effects, and c-CPE, as a targeting tag, synergistically assist to stimulate systemic and local immunity. This proposed recombinant S. boulardii system might be useful in the expression of other antigenic peptides, making it as a promising tool for oral delivery of vaccines or therapeutic

Production of recombinant dengue non-structural 1 (NS1) proteins from clinical virus isolates.

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Yohan, Benediktus; Wardhani, Puspa; Aryati; Trimarsanto, Hidayat; Sasmono, R Tedjo

2017-01-01

Dengue is a febrile disease caused by infection of dengue virus (DENV). Early diagnosis of dengue infection is important for better management of the disease. The DENV Non-Structural Protein 1 (NS1) antigen has been routinely used for the early dengue detection. In dengue epidemic countries such as Indonesia, clinicians are increasingly relying on the NS1 detection for confirmation of dengue infection. Various NS1 diagnostic tests are commercially available, however different sensitivities and specificities were observed in various settings. This study was aimed to generate dengue NS1 recombinant protein for the development of dengue diagnostic tests. Four Indonesian DENV isolates were used as the source of the NS1 gene cloning, expression, and purification in bacterial expression system. Recombinant NS1 proteins were successfully purified and their antigenicities were assessed. Immunization of mice with recombinant proteins observed the immunogenicity of the NS1 protein. The generated recombinant proteins can be potentially used in the development of NS1 diagnostic test. With minimal modifications, this method can be used for producing NS1 recombinant proteins from isolates obtained from other geographical regions. Copyright © 2016 Elsevier Inc. All rights reserved.

Stabilizing additives added during cell lysis aid in the solubilization of recombinant proteins.

Directory of Open Access Journals (Sweden)

David J Leibly

Full Text Available Insoluble recombinant proteins are a major issue for both structural genomics and enzymology research. Greater than 30% of recombinant proteins expressed in Escherichia coli (E. coli appear to be insoluble. The prevailing view is that insolubly expressed proteins cannot be easily solubilized, and are usually sequestered into inclusion bodies. However, we hypothesize that small molecules added during the cell lysis stage can yield soluble protein from insoluble protein previously screened without additives or ligands. We present a novel screening method that utilized 144 additive conditions to increase the solubility of recombinant proteins expressed in E. coli. These selected additives are natural ligands, detergents, salts, buffers, and chemicals that have been shown to increase the stability of proteins in vivo. We present the methods used for this additive solubility screen and detailed results for 41 potential drug target recombinant proteins from infectious organisms. Increased solubility was observed for 80% of the recombinant proteins during the primary and secondary screening of lysis with the additives; that is 33 of 41 target proteins had increased solubility compared with no additive controls. Eleven additives (trehalose, glycine betaine, mannitol, L-Arginine, potassium citrate, CuCl(2, proline, xylitol, NDSB 201, CTAB and K(2PO(4 solubilized more than one of the 41 proteins; these additives can be easily screened to increase protein solubility. Large-scale purifications were attempted for 15 of the proteins using the additives identified and eight (40% were prepared for crystallization trials during the first purification attempt. Thus, this protocol allowed us to recover about a third of seemingly insoluble proteins for crystallography and structure determination. If recombinant proteins are required in smaller quantities or less purity, the final success rate may be even higher.

S100A6 - New facts and features

Energy Technology Data Exchange (ETDEWEB)

Lesniak, Wieslawa; Slomnicki, Lukasz P. [Department of Molecular and Cellular Neurobiology, Nencki Institute of Experimental Biology, 02-093 Warsaw (Poland); Filipek, Anna, E-mail: a.filipek@nencki.gov.pl [Department of Molecular and Cellular Neurobiology, Nencki Institute of Experimental Biology, 02-093 Warsaw (Poland)

2009-12-25

S100A6 (calcyclin) is a 10.5 kDa Ca{sup 2+}-binding protein that belongs to the S100 protein family. S100A6 contains two EF-hand motifs responsible for binding of Ca{sup 2+}. It also binds Zn{sup 2+} through not yet identified structures. Binding of Ca{sup 2+} induces a conformational change in the S100A6 molecule which in consequence increases its overall hydrophobicity and allows for interaction with target proteins. S100A6 was found in different mammalian and avian (chicken) tissues. A high level of S100A6 is observed in epithelial cells, fibroblasts and in different kinds of cancer cells. The function of S100A6 is not clear at present, but it has been suggested that it may be involved in cell proliferation, cytoskeletal dynamics and tumorigenesis. Additionally, S100A6 might have some extracellular activities. This review presents new facts and features concerning the S100A6 protein.

Brucella melitensis VirB12 recombinant protein is a potential marker for serodiagnosis of human brucellosis.

Science.gov (United States)

Mirkalantari, Shiva; Zarnani, Amir-Hassan; Nazari, Mahboobeh; Irajian, Gholam Reza; Amirmozafari, Nour

2017-03-03

The numerous drawbacks of current serological tests for diagnosis of brucellosis which mainly results from cross reactivity with LPS from other gram-negative bacteria have generated an increasing interest to find more specific non-LPS antigens. Previous studies had indicated that Brucella VirB12 protein, a cell surface protein and component of type IV secretion system, induces antibody response during animal infection. However, this protein has not yet been tested as a serological diagnostic marker in human brucellosis. Recombinant VirB12 protein was prepared and evaluated the efficacy of it in an indirect enzyme-linked immunosorbent assay (ELISA) for brucellosis with sera collected from different region of Iran and the results were compared with a commercial ELISA kit. Sera from human brucellosis patients strongly reacted to the purified recombinant VirB12. The sensitivity, specificity, accuracy, negative predictive value and positive predictive value of recombinant VirB12-based ELISA related to the commercial-ELISA method were 87.8, 94, 90, 80 and 96.6% respectively. We concluded that antigenic VirB12 have a property value that can be considered as a candidate for using in serodiagnostic tests for human brucellosis.

The metastasis-associated Mts1(S100A4) protein could act as an angiogenic factor

DEFF Research Database (Denmark)

Ambartsumian, N; Klingelhöfer, Jörg; Grigorian, M

2001-01-01

The involvement of Mts1(S100A4), a small Ca(2+)-binding protein in tumor progression and metastasis had been demonstrated. However, the mechanism by which mts1(S100A4) promoted metastasis had not been identified. Here we demonstrated that Mts1(S100A4) had significant stimulatory effect on the ang...

Diagnostic value of recombinant Tp0821 protein in serodiagnosis for syphilis.

Science.gov (United States)

Xie, Y; Xu, M; Wang, C; Xiao, J; Xiao, Y; Jiang, C; You, X; Zhao, F; Zeng, T; Liu, S; Kuang, X; Wu, Y

2016-04-01

Syphilis is a multistage sexually transmitted disease that remains a serious public health concern worldwide. The coexistence of Treponema pallidum with other closely related members of spirochaeta, such as Leptospira spp. and Borrelia burgdorferi, has complicated the serodiagnosis due to cross-reactive antigens. In this study, recombinant Tp0821 protein was expressed in Escherichia coli and purified by metal affinity chromatography. Then enzyme-linked immunosorbent assays (ELISAs) based on Tp0821 for the detection of specific antibodies were established. The relative positive rates of the IgM ELISA and the IgG ELISA were found to be 91·0 and 98·3%, respectively, when screening 578 syphilis specimens. The specificities were 94·3 and 100%, respectively, when cross-checking with serum samples obtained from 30 patients with Lyme disease, five patients with leptospirosis, and 52 uninfected controls. In addition, relative positive rates and specificities of Tp0821 for human sera were all 100% in Western blotting. When compared to the syphilis diagnostic tests commonly used in clinical settings, we found that the results of Tp0821-based ELISAs correlated well with the results of the treponemal tests, specifically the T. pallidum particle agglutination (TP-PA) test and the chemiluminescent immunoassay (CIA). Thus, these findings identify Tp0821 as a novel serodiagnostic candidate for syphilis. In this study, we expressed and purified the Treponema pallidum protein Tp0821 and developed Tp0821-based enzyme-linked immunosorbent assays (ELISAs) for the detection of specific antibodies. The serodiagnostic performance of the recombinant protein was then evaluated. When compared to the results of syphilis diagnostic tests commonly used in clinical settings, we found that the reactivities of syphilitic sera with the recombinant antigen correlated well with the results of the treponemal tests, specifically the T. pallidum particle agglutination (TP-PA) test and the

Reference values for venous and capillary S100B in children

DEFF Research Database (Denmark)

Astrand, Ramona; Romner, Bertil; Lanke, Jan

2011-01-01

The current management guidelines for pediatric mild head injury (MHI) liberally recommend computed tomography (CT) and frequent admission. Serum protein S100B, currently used in management of adult head injury, has recently shown potential for reducing unnecessary CT scans after pediatric mild h...... head injury. Capillary sampling in children is commonly used when venous sampling fails or is inappropriate. We present reference values for both venous and capillary samples of protein S100B in children....

S100B Protein concentration in milk-formulas for preterm and term infants. Correlation with industrial preparation procedures.

Science.gov (United States)

Nigro, Francesco; Gagliardi, Luigi; Ciotti, Sabina; Galvano, Fabio; Pietri, Amedeo; Tina, Gabriella Lucia; Cavallaro, Daniela; La Fauci, Luca; Iacopino, Leonardo; Bognanno, Matteo; Li Volti, Giovanni; Scacco, Antonio; Michetti, Fabrizio; Gazzolo, Diego

2008-05-01

Human milk S100B protein possesses important neurotrophic properties. However, in some conditions human milk is substituted by milk formulas. The aims of the present study were: to assess S100B concentrations in milk formulas, to verify any differences in S100B levels between preterm and term infant formulas and to evaluate the impact of industrial preparation at predetermined phases on S100B content. Two different set of samples were tested: (i) commercial preterm (n = 36) and term (n = 36) infant milk formulas; ii) milk preterm (n = 10) and term infant (n = 10) formulas sampled at the following predetermined industrial preparation time points: skimmed cow milk (Time 0); after protein sources supplementation (Time 1); after pasteurization (Time 2); after spray-drying (Time 3). Our results showed that S100B concentration in preterm formulas were higher than in term ones (p 0.05) at Time 2, whereas a significant (p pasteurization but not spry-drying. New feeding strategies in preterm and term infants are therefore warranted in order to preserve S100B protein during industrial preparation.

Insect Larvae: A New Platform to Produce Commercial Recombinant Proteins.

Science.gov (United States)

Targovnik, Alexandra M; Arregui, Mariana B; Bracco, Lautaro F; Urtasun, Nicolas; Baieli, Maria F; Segura, Maria M; Simonella, Maria A; Fogar, Mariela; Wolman, Federico J; Cascone, Osvaldo; Miranda, Maria V

2016-01-01

In Biotechnology, the expression of recombinant proteins is a constantly growing field and different hosts are used for this purpose. Some valuable proteins cannot be produced using traditional systems. Insects from the order Lepidoptera infected with recombinant baculovirus have appeared as a good choice to express high levels of proteins, especially those with post-translational modifications. Lepidopteran insects, which are extensively distributed in the world, can be used as small protein factories, the new biofactories. Species like Bombyx mori (silkworm) have been analyzed in Asian countries to produce a great number of recombinant proteins for use in basic and applied science and industry. Many proteins expressed in this larva have been commercialized. Several recombinant proteins produced in silkworms have already been commercialized. On the other hand, species like Spodoptera frugiperda, Heliothis virescens, Rachiplusia nu, Helicoverpa zea and Trichoplusia ni are widely distributed in both the occidental world and Europe. The expression of recombinant proteins in larvae has the advantage of its low cost in comparison with insect cell cultures. A wide variety of recombinant proteins, including enzymes, hormones and vaccines, have been efficiently expressed with intact biological activity. The expression of pharmaceutically proteins, using insect larvae or cocoons, has become very attractive. This review describes the use of insect larvae as an alternative to produce commercial recombinant proteins.

Oral Administration of Recombinant Saccharomyces boulardii Expressing Ovalbumin-CPE Fusion Protein Induces Antibody Response in Mice.

Science.gov (United States)

Bagherpour, Ghasem; Ghasemi, Hosnie; Zand, Bahare; Zarei, Najmeh; Roohvand, Farzin; Ardakani, Esmat M; Azizi, Mohammad; Khalaj, Vahid

2018-01-01

Saccharomyces boulardii , a subspecies of Saccharomyces cerevisiae , is a well-known eukaryotic probiotic with many benefits for human health. In the present study, a recombinant strain of S. boulardii was prepared to use as a potential oral vaccine delivery vehicle. In this sense, a ura3 auxotroph strain of S. boulardii CNCM I-745 (known as S. cerevisiae HANSEN CBS 5926, Yomogi ® ) was generated using CRISPR/Cas9 methodology. Then a gene construct encoding a highly immunogenic protein, ovalbumin (OVA), was prepared and transformed into the ura3 - S. boulardii . To facilitate the transport of the recombinant immunogen across the intestinal barrier, a claudin-targeting sequence from Clostridium perfringens enterotoxin (CPE) was added to the C-terminus of the expression cassette. The recombinant S. boulardii strain expressing the OVA-CPE fusion protein was then administered orally to a group of mice, and serum IgG and fecal IgA levels were evaluated by ELISA. Our results demonstrated that anti-OVA IgG in serum significantly increased in test group ( P boulardii or PBS), and the fecal IgA titer was significantly higher in test group ( P boulardii strain expressing the similar construct lacking C-terminal CPE was also administered orally. The result showed an increased level of serum IgG in group receiving yeasts expressing the CPE negative construct compared to control groups; however, the fecal IgA levels did not increase significantly. In conclusion, our findings indicated that the yeast S. boulardii , as a delivery vehicle with possible immunomodulatory effects, and c-CPE, as a targeting tag, synergistically assist to stimulate systemic and local immunity. This proposed recombinant S. boulardii system might be useful in the expression of other antigenic peptides, making it as a promising tool for oral delivery of vaccines or therapeutic proteins.

High-yield secretion of recombinant proteins from the microalga Chlamydomonas reinhardtii.

Science.gov (United States)

Ramos-Martinez, Erick Miguel; Fimognari, Lorenzo; Sakuragi, Yumiko

2017-09-01

Microalga-based biomanufacturing of recombinant proteins is attracting growing attention due to its advantages in safety, metabolic diversity, scalability and sustainability. Secretion of recombinant proteins can accelerate the use of microalgal platforms by allowing post-translational modifications and easy recovery of products from the culture media. However, currently, the yields of secreted recombinant proteins are low, which hampers the commercial application of this strategy. This study aimed at expanding the genetic tools for enhancing secretion of recombinant proteins in Chlamydomonas reinhardtii, a widely used green microalga as a model organism and a potential industrial biotechnology platform. We demonstrated that the putative signal sequence from C. reinhardtii gametolysin can assist the secretion of the yellow fluorescent protein Venus into the culture media. To increase the secretion yields, Venus was C-terminally fused with synthetic glycomodules comprised of tandem serine (Ser) and proline (Pro) repeats of 10 and 20 units [hereafter (SP) n , wherein n = 10 or 20]. The yields of the (SP) n -fused Venus were higher than Venus without the glycomodule by up to 12-fold, with the maximum yield of 15 mg/L. Moreover, the presence of the glycomodules conferred an enhanced proteolytic protein stability. The Venus-(SP) n proteins were shown to be glycosylated, and a treatment of the cells with brefeldin A led to a suggestion that glycosylation of the (SP) n glycomodules starts in the endoplasmic reticulum (ER). Taken together, the results demonstrate the utility of the gametolysin signal sequence and (SP) n glycomodule to promote a more efficient biomanufacturing of microalgae-based recombinant proteins. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

A synthetic arabinose-inducible promoter confers high levels of recombinant protein expression in hyperthermophilic archaeon Sulfolobus islandicus

DEFF Research Database (Denmark)

Peng, Nan; Deng, Ling; Mei, Yuxia

2012-01-01

Despite major progresses in genetic studies of hyperthermophilic archaea, recombinant protein production in these organisms always suffers from low yields and a robust expression system is still in great demand. Here we report a versatile vector that confers high levels of protein expression...... to remove the peptide tags from expressed recombinant proteins. While pEXA employed an araS promoter for protein expression, pSeSD utilized P(araS-SD), an araS derivative promoter carrying an engineered ribosome-binding site (RBS; a Shine-Dalgarno [SD] sequence). We found that P(araS-SD) directed high...... levels of target gene expression. More strikingly, N-terminal amino acid sequencing of recombinant proteins unraveled that the protein synthesized from pEXA-N-lacS lacked the designed 6×His tag and that translation initiation did not start at the ATG codon of the fusion gene. Instead, it started...

Photosynthetic biomanufacturing in green algae; production of recombinant proteins for industrial, nutritional, and medical uses.

Science.gov (United States)

Rasala, Beth A; Mayfield, Stephen P

2015-03-01

Recombinant proteins are widely used for industrial, nutritional, and medical applications. Green microalgae have attracted considerable attention recently as a biomanufacturing platform for the production of recombinant proteins for a number of reasons. These photosynthetic eukaryotic microorganisms are safe, scalable, easy to genetically modify through transformation, mutagenesis, or breeding, and inexpensive to grow. Many microalgae species are genetically transformable, but the green alga Chlamydomonas reinhardtii is the most widely used host for recombinant protein expression. An extensive suite of molecular genetic tools has been developed for C. reinhardtii over the last 25 years, including a fully sequenced genome, well-established methods for transformation, mutagenesis and breeding, and transformation vectors for high levels of recombinant protein accumulation and secretion. Here, we review recent successes in the development of C. reinhardtii as a biomanufacturing host for recombinant proteins, including antibodies and immunotoxins, hormones, industrial enzymes, an orally-active colostral protein for gastrointestinal health, and subunit vaccines. In addition, we review the biomanufacturing potential of other green algae from the genera Dunaliella and Chlorella.

Comparison between capillary, venous and arterial levels of protein S100B in patients with severe brain pathology

DEFF Research Database (Denmark)

Astrand, Ramona; Romner, Bertil; Reinstrup, Peter

2012-01-01

of the study was to investigate the relation between capillary, venous and arterial measurements of protein S100B, primarily by determining whether capillary S100B differ from venous and if capillary S100B can predict venous S100B levels, and secondarily, if arterial S100B samples can substitute venous samples...... in severely brain-injured patients....

Two potential recombinant rabies vaccines expressing canine parvovirus virion protein 2 induce immunogenicity to canine parvovirus and rabies virus.

Science.gov (United States)

Luo, Jun; Shi, Hehe; Tan, Yeping; Niu, Xuefeng; Long, Teng; Zhao, Jing; Tian, Qin; Wang, Yifei; Chen, Hao; Guo, Xiaofeng

2016-08-17

Both rabies virus (RABV) and canine parvovirus (CPV) cause lethal diseases in dogs. In this study, both high egg passage Flury (HEP-Flury) strains of RABV and recombinant RABV carrying double RABV glycoprotein (G) gene were used to express the CPV virion protein 2 (VP2) gene, and were designated rHEP-VP2 and, rHEP-dG-VP2 respectively. The two recombinant RABVs maintained optimal virus titration according to their viral growth kinetics assay compared with the parental strain HEP-Flury. Western blotting indicated that G protein and VP2 were expressed in vitro. The expression of VP2 in Crandell feline kidney cells post-infection by rHEP-VP2 and rHEP-dG-VP2 was confirmed by indirect immunofluorescence assay with antibody against VP2. Immunogenicity of recombinant rabies viruses was tested in Kunming mice. Both rHEP-VP2 and rHEP-dG-VP2 induced high levels of rabies antibody compared with HEP-Flury. Mice immunized with rHEP-VP2 and rHEP-dG-VP2 both had a high level of antibodies against VP2, which can protect against CPV infection. A challenge experiment indicated that more than 80% mice immunized with recombinant RABVs survived after infection of challenge virus standard 24 (CVS-24). Together, this study showed that recombinant RABVs expressing VP2 induced protective immune responses to RABV and CPV. Therefore, rHEP-VP2 and rHEP-dG-VP2 might be potential combined vaccines for RABV and CPV. Copyright © 2016 Elsevier Ltd. All rights reserved.

S100B protein, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor in human milk.

Directory of Open Access Journals (Sweden)

Ruisong Li

Full Text Available Human milk contains a wide variety of nutrients that contribute to the fulfillment of its functions, which include the regulation of newborn development. However, few studies have investigated the concentrations of S100B protein, brain-derived neurotrophic factor (BDNF, and glial cell line-derived neurotrophic factor (GDNF in human milk. The associations of the concentrations of S100B protein, BDNF, and GDNF with maternal factors are not well explored.To investigate the concentrations of S100B protein, BDNF, and GDNF in human milk and characterize the maternal factors associated with their levels in human milk, human milk samples were collected at days 3, 10, 30, and 90 after parturition. Levels of S100B protein, BDNF, and GDNF, and their mRNAs in the samples were detected. Then, these concentrations were compared with lactation and other maternal factors. S100B protein levels in human milk samples collected at 3, 10, 30, and 90 d after parturition were 1249.79±398.10, 1345.05±539.16, 1481.83±573.30, and 1414.39±621.31 ng/L, respectively. On the other hand, the BDNF concentrations in human milk samples were 10.99±4.55, 13.01±5.88, 13.35±6.43, and 2.83±5.47 µg/L, while those of GDNF were 10.90±1.65, 11.38±1., 11.29±3.10, and 11.40±2.21 g/L for the same time periods. Maternal post-pregnancy body mass index was positively associated with S100B levels in human milk (r = 0.335, P = 0.030<0.05. In addition, there was a significant correlation between the levels of S100B protein and BDNF (z = 2.09, P = 0.037<0.05. Delivery modes were negatively associated with the concentration of GDNF in human milk.S100B protein, BDNF, and GDNF are present in all samples of human milk, and they may be responsible for the long term effects of breast feeding.

Engineered mammalian cells for production of recombinant proteins

DEFF Research Database (Denmark)

2017-01-01

The present invention relates to mammalian cells modified to provide for improved expression of a recombinant protein of interest. In particular, the invention relates to CHO cells and other host cells in which the expression of one or more endogenous secreted proteins has been disrupted, as well...... as to the preparation, identification and use of such cells in the production of recombinant proteins....

Attenuation of cancer-initiating cells stemness properties by abrogating S100A4 calcium binding ability in head and neck cancers.

Science.gov (United States)

Cheng, Li-Hao; Hung, Kai-Feng; Huang, Tung-Fu; Hsieh, Hsin-Pei; Wang, Shu-Ying; Huang, Chih-Yang; Lo, Jeng-Fan

2016-11-29

S100A4 is a calcium-binding protein capable of promoting epithelial-mesenchymal transition. Previously, we have demonstrated that S100A4 is required to sustain the head and neck cancer-initiating cells (HN-CICs) subpopulation. In this study, to further investigate the molecular mechanism, we established the head and neck squamous cell carcinoma (HNSCC) cell lines stably expressing mutant S100A4 proteins with defective calcium-binding sites on either N-terminal (NM) or C-terminal (CM), or a deletion of the last 15 amino-acid residues (CD). We showed that the NM, CM and CD harboring sphere cells that were enriched with HN-CICs population exhibited impaired stemness and malignant properties in vitro, as well as reduced tumor growth ability in vivo. Mechanistically, we demonstrated that mutant S100A4 proteins decreased the promoter activity of Nanog, likely through inhibition of p53. Moreover, the biophysical analyses of purified recombinant mutant S100A4 proteins suggest that both NM and CM mutant S100A4 were very similar to the WT S100A4 with subtle difference on the secondary structure, and that the CD mutant protein displayed the unexpected monomeric form in the solution phase.Taken together, our results suggest that both the calcium-binding ability and the C-terminal region of S100A4 are important for HN-CICs to sustain its stemness property and malignancy, and that the mechanism could be mediated by repressing p53 and subsequently activating the Nanog expression.

Polymyxin B as inhibitor of LPS contamination of Schistosoma mansoni recombinant proteins in human cytokine analysis

Directory of Open Access Journals (Sweden)

Pacífico Lucila G

2007-01-01

Full Text Available Abstract Background Recombinant proteins expressed in Escherichia coli vectors are generally contaminated with endotoxin. In this study, we evaluated the ability of Polymyxin B to neutralize the effect of LPS present as contaminant on Schistosoma mansoni recombinant proteins produced in E. coli in inducing TNF-α and IL-10. Peripheral blood mononuclear cells from individuals chronically infected with S. mansoni were stimulated in vitro with recombinant Sm22.6, Sm14 and P24 antigens (10 μg/mL in the presence of Polymyxin B (10 μg/mL. Results The levels of cytokines were measured using ELISA. There was greater than 90 % reduction (p S. mansoni recombinant proteins in the presence of Polymyxin B, a reduction in the levels of TNF-α and IL-10 was also observed. However, the percentage of reduction was lower when compared to the cultures stimulated with LPS, probably because these proteins are able to induce the production of these cytokines by themselves. Conclusion This study showed that Polymyxin B was able to neutralize the effect of endotoxin, as contaminant in S. mansoni recombinant antigens produced in E. coli, in inducing TNF-α and IL-10 production.

Analysis of Recombinant Proteins in Transgenic Rice Seeds: Identity, Localization, Tolerance to Digestion, and Plant Stress Response.

Science.gov (United States)

Wakasa, Yuhya; Takaiwa, Fumio

2016-01-01

Rice seeds are an ideal production platform for high-value recombinant proteins in terms of economy, scalability, safety, and stability. Strategies for the expression of large amounts of recombinant proteins in rice seeds have been established in the past decade and transgenic rice seeds that accumulate recombinant products such as bioactive peptides and proteins, which promote the health and quality of life of humans, have been generated in many laboratories worldwide. One of the most important advantages is the potential for direct oral delivery of transgenic rice seeds without the need for recombinant protein purification (downstream processing), which has been attributed to the high expression levels of recombinant products. Transgenic rice will be beneficial as a delivery system for pharmaceuticals and nutraceuticals in the future. This chapter introduces the strategy for producing recombinant protein in the edible part (endosperm) of the rice grain and describes methods for the analysis of transgenic rice seeds in detail.

Proteomics unveil corticoid-induced S100A11 shuttling in keratinocyte differentiation

International Nuclear Information System (INIS)

Dezitter, Xavier; Hammoudi, Fatma; Belverge, Nicolas; Deloulme, Jean-Christophe; Drobecq, Herve; Masselot, Bernadette; Formstecher, Pierre; Mendy, Denise; Idziorek, Thierry

2007-01-01

Unlike classical protein extraction techniques, proteomic mapping using a selective subcellular extraction kit revealed S100A11 as a new member of the S100 protein family modulated by glucocorticoids in keratinocytes. Glucocorticoids (GC)-induced S100A11 redistribution in the 'organelles and membranes' compartment. Microscopic examination indicated that glucocorticoids specifically routed cytoplasmic S100A11 toward perinuclear compartment. Calcium, a key component of skin terminal differentiation, directed S100A11 to the plasma membrane as previously reported. When calcium was added to glucocorticoids, minor change was observed at the proteomic level while confocal microscopy revealed a rapid and dramatic translocation of S100A11 toward plasma membrane. This effect was accompanied by strong nuclear condensation, loss of mitochondrial potential and DNA content, and increased high molecular weight S100A11 immunoreactivity, suggesting corticoids accelerate calcium-induced terminal differentiation. Finally, our results suggest GC-induced S100A11 relocalization could be a key step in both keratinocyte homeostasis and glucocorticoids side effects in human epidermis

Improved means and methods for expressing recombinant proteins

NARCIS (Netherlands)

Poolman, Berend; Martinez Linares, Daniel; Gul, Nadia

2014-01-01

The invention relates to the field of genetic engineering and the production of recombinant proteins in microbial host cells. Provided is a method for enhanced expression of a recombinant protein of interest in a microbial host cell, comprising providing a microbial host cell wherein the function of

Immune responses induced by recombinant Bacillus subtilis expressing the spike protein of transmissible gastroenteritis virus in pigs.

Science.gov (United States)

Mou, Chunxiao; Zhu, Liqi; Xing, Xianping; Lin, Jian; Yang, Qian

2016-07-01

Transmissible gastroenteritis (TGE) causes severe diarrhea in suckling piglets, results in enormous economic loss in swine-producing areas of the world. To develop an effective, safe, and convenient vaccine for the prevention of TGE, we have constructed a recombinant Bacillus subtilis strain (B. subtilis CotGSG) displaying the transmissible gastroenteritis virus (TGEV) spike (S) protein and discussed its immune function to intestinal submucosal dendritic cells (DCs). Our results showed that the recombinant B. subtilis had the ability to recruit more DCs to sample B. subtilis CotGSG, migrate to MLNs, and induce immune responses. Immunized piglets with B. subtilis CotGSG could significantly elevate the specific SIgA titers in feces, IgG titers and neutralizing antibodies in serum. Collectively, our results suggested that recombinant B. subtilis CotGSG expressing the TGEV S protein could effectively induce immune responses via DCs, and provided a perspective on potential novel strategy and approach that may be applicable to the development of the next generation of TGEV vaccines. Copyright © 2016 Elsevier B.V. All rights reserved.

New insights into the evolutionary origins of the recombination-activating gene proteins and V(D)J recombination.

Science.gov (United States)

Carmona, Lina Marcela; Schatz, David G

2017-06-01

The adaptive immune system of jawed vertebrates relies on V(D)J recombination as one of the main processes to generate the diverse array of receptors necessary for the recognition of a wide range of pathogens. The DNA cleavage reaction necessary for the assembly of the antigen receptor genes from an array of potential gene segments is mediated by the recombination-activating gene proteins RAG1 and RAG2. The RAG proteins have been proposed to originate from a transposable element (TE) as they share mechanistic and structural similarities with several families of transposases and are themselves capable of mediating transposition. A number of RAG-like proteins and TEs with sequence similarity to RAG1 and RAG2 have been identified, but only recently has their function begun to be characterized, revealing mechanistic links to the vertebrate RAGs. Of particular significance is the discovery of ProtoRAG, a transposon superfamily found in the genome of the basal chordate amphioxus. ProtoRAG has many of the sequence and mechanistic features predicted for the ancestral RAG transposon and is likely to be an evolutionary relative of RAG1 and RAG2. In addition, early observations suggesting that RAG1 is able to mediate V(D)J recombination in the absence of RAG2 have been confirmed, implying independent evolutionary origins for the two RAG genes. Here, recent progress in identifying and characterizing RAG-like proteins and the TEs that encode them is summarized and a refined model for the evolution of V(D)J recombination and the RAG proteins is presented. © 2016 Federation of European Biochemical Societies.

Serum from Nipah Virus Patients Recognises Recombinant Viral Proteins Produced in Escherichia coli.

Science.gov (United States)

Tiong, Vunjia; Lam, Chui-Wan; Phoon, Wai-Hong; AbuBakar, Sazaly; Chang, Li-Yen

2017-01-24

The genes for Nipah virus (NiV) proteins were amplified from viral RNA, cloned into the plasmid pTriEx-3 Hygro, expressed, and purified using immobilized metal affinity chromatography. The recombinant N, F, and G NiV proteins (rNiV-N, rNiV-F, and rNiV-G), were successfully expressed in Escherichia coli and purified with a yield of 4, 16, and 4 mg/L, respectively. All 3 recombinant viral proteins reacted with all 19 samples of NiV-positive human sera. The rNiV-N and rNiV-G proteins were the most immunogenic. The recombinant viral proteins did not react with any of the 12 NiV-negative sera. However, serum from a patient with a late-onset relapsing NiV infection complication was found to be primarily reactive to rNiV-G only. Additionally, there is a distinctive variation in the profile of antigen-reactive bands between the sample from a case of relapsing NiV encephalitis and that of acute NiV infection. The overall findings of this study suggest that the recombinant viral proteins have the potential to be developed further for use in the detection of NiV infection, and continuous biosurveillance of NiV infection in resource-limited settings.

Expression of Slug in S100β-protein-positive cells of postnatal developing rat anterior pituitary gland.

Science.gov (United States)

Horiguchi, Kotaro; Fujiwara, Ken; Tsukada, Takehiro; Yako, Hideji; Tateno, Kozue; Hasegawa, Rumi; Takigami, Shu; Ohsako, Shunji; Yashiro, Takashi; Kato, Takako; Kato, Yukio

2016-02-01

Among heterogeneous S100β-protein-positive (S100β-positive) cells, star-like cells with extended cytoplasmic processes, the so-called folliculo-stellate cells, envelop hormone-producing cells or interconnect homophilically in the anterior pituitary. S100β-positive cells are known, from immunohistochemistry, to emerge from postnatal day (P) 10 and to proliferate and migrate in the parenchyma of the anterior pituitary with growth. Recent establishment of S100β-GFP transgenic rats expressing specifically green fluorescent protein (GFP) under the control of the S100β-promoter has allowed us to observe living S100β-positive cells. In the present study, we first confirmed that living S100β-positive cells in tissue cultures of S100β-GFP rat pituitary at P5 were present prior to P10 by means of confocal laser microscopy and that they proliferated and extended their cytoplasmic processes. Second, we examined the expression of the Snail-family zinc-finger transcription factors, Snail and Slug, to investigate the mechanism behind the morphological changes and the proliferation of S100β-positive cells. Interestingly, we detected Slug expression in S100β-positive cells and its increase together with development in the anterior pituitary. To analyze downstream of SLUG in S100β-positive cells, we utilized specific small interfering RNA for Slug mRNAs and observed that the expression of matrix metalloprotease (Mmp) 9, Mmp14 and chemokine Cxcl12 was down-regulated and that morphological changes and proliferation were decreased. Thus, our findings suggest that S100β-positive cells express Slug and that its expression is important for subsequent migration and proliferation.

Hydroxyapatite coating on the titanium substrate modulated by a recombinant collagen-like protein

International Nuclear Information System (INIS)

Pan Mingli; Kong Xiangdong; Cai Yurong; Yao Juming

2011-01-01

Research highlights: → Hydroxyapatite was deposited on alkali-heat treated Ti substrate by immersing in 1.5 x SBF solution containing the recombinant collagen-like protein. → The recombinant collagen-like protein accelerated the preferential nucleation and growth of hydroxyapatite along c axis on the Ti substrate. → Hydroxyapatite-collagen composite on the Ti substrate promoted the attachment, subsequently proliferation and differentiation of MG-63 cells. - Abstract: Plenty of techniques have been developed to modify the surface character of titanium (Ti) and its alloys in order to realize their biological bond to natural bone. In this work, a biomimetic process was employed to form a hydroxyapatite (HAp) coating on the alkali-heat treated Ti substrate in 1.5 times simulated body fluid (1.5 x SBF) with the addition of a recombinant collagen-like protein. The coating was characterized using SEM-EDX, FESEM, and XRD. Results showed that the recombinant collagen-like protein could accelerate the preferential nucleation and directional growth along c axis of HAp on the pretreated Ti substrates. The investigation of in vitro cell cultivation showed that the existence of recombinant collagen-like protein in coating could improve the initial cell adhesion, proliferation and differentiation of MG-63 cells, which implied the materials possessed excellent biocompatibility and had a wide potential in biomedical application.

Hydroxyapatite coating on the titanium substrate modulated by a recombinant collagen-like protein

Energy Technology Data Exchange (ETDEWEB)

Pan Mingli [Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Ministry of Education, College of Materials and Textile, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Kong Xiangdong [College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Cai Yurong [Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Ministry of Education, College of Materials and Textile, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Yao Juming, E-mail: yaoj@zstu.edu.cn [Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Ministry of Education, College of Materials and Textile, Zhejiang Sci-Tech University, Hangzhou 310018 (China)

2011-04-15

Research highlights: {yields} Hydroxyapatite was deposited on alkali-heat treated Ti substrate by immersing in 1.5 x SBF solution containing the recombinant collagen-like protein. {yields} The recombinant collagen-like protein accelerated the preferential nucleation and growth of hydroxyapatite along c axis on the Ti substrate. {yields} Hydroxyapatite-collagen composite on the Ti substrate promoted the attachment, subsequently proliferation and differentiation of MG-63 cells. - Abstract: Plenty of techniques have been developed to modify the surface character of titanium (Ti) and its alloys in order to realize their biological bond to natural bone. In this work, a biomimetic process was employed to form a hydroxyapatite (HAp) coating on the alkali-heat treated Ti substrate in 1.5 times simulated body fluid (1.5 x SBF) with the addition of a recombinant collagen-like protein. The coating was characterized using SEM-EDX, FESEM, and XRD. Results showed that the recombinant collagen-like protein could accelerate the preferential nucleation and directional growth along c axis of HAp on the pretreated Ti substrates. The investigation of in vitro cell cultivation showed that the existence of recombinant collagen-like protein in coating could improve the initial cell adhesion, proliferation and differentiation of MG-63 cells, which implied the materials possessed excellent biocompatibility and had a wide potential in biomedical application.

Serum levels of psoriasin (S100A7) and koebnerisin (S100A15) as potential markers of atherosclerosis in patients with psoriasis.

Science.gov (United States)

Awad, S M; Attallah, D A; Salama, R H; Mahran, A M; Abu El-Hamed, E

2018-04-01

Psoriasin (S100A7) and koebnerisin (S100A15) are proinflammatory proteins upregulated in psoriasis, but their relation to atherosclerosis remains unclear. To evaluate the role of serum psoriasin and koebnerisin as possible markers for subclinical atherosclerosis in patients with psoriasis. Serum levels of psoriasin and koebnerisin were measured by ELISA in 45 patients with psoriasis and in 45 healthy controls (HCs). Intima-media thickness (IMT) of the right and left common carotid arteries was measured to detect the presence of subclinical atherosclerosis. Clinical severity of psoriasis was estimated using the Psoriasis Area and Severity Index (PASI). Compared with HCs, patients with psoriasis had significantly higher levels of psoriasin (26.61 ± 22.45 ng/mL vs. 6.31 ± 1.68 ng/mL, P  0.01) and serum koebnerisin (r = 0.48, P psoriasis with subclinical atherosclerosis had higher serum levels of koebnerisin compared with patients without subclinical atherosclerosis (P = 0.04), which was not observed for psoriasin (P = 0.94). Serum psoriasin and koebnerisin correlate with IMT, underlining their value as a potential link between psoriasis and atherosclerosis. In particular, koebnerisin seems to be a useful marker of subclinical atherosclerosis in patients with psoriasis. © 2018 British Association of Dermatologists.

Co-solute assistance in refolding of recombinant proteins | Gerami ...

African Journals Online (AJOL)

Prokaryotic expression system is the most widely used host for the production of recombinant proteins but inclusion body formation is a major bottleneck in the production of recombinant proteins in prokaryotic cells, especially in Escherichia coli. In vitro refolding of inclusion body into the the proteins with native ...

Metal binding proteins, recombinant host cells and methods

Science.gov (United States)

Summers, Anne O.; Caguiat, Jonathan J.

2004-06-15

The present disclosure provides artificial heavy metal binding proteins termed chelons by the inventors. These chelons bind cadmium and/or mercuric ions with relatively high affinity. Also disclosed are coding sequences, recombinant DNA molecules and recombinant host cells comprising those recombinant DNA molecules for expression of the chelon proteins. In the recombinant host cells or transgenic plants, the chelons can be used to bind heavy metals taken up from contaminated soil, groundwater or irrigation water and to concentrate and sequester those ions. Recombinant enteric bacteria can be used within the gastrointestinal tracts of animals or humans exposed to toxic metal ions such as mercury and/or cadmium, where the chelon recombinantly expressed in chosen in accordance with the ion to be rededicated. Alternatively, the chelons can be immobilized to solid supports to bind and concentrate heavy metals from a contaminated aqueous medium including biological fluids.

High-yield secretion of recombinant proteins from the microalga Chlamydomonas reinhardtii

DEFF Research Database (Denmark)

Ramos Martinez, Erick Miguel; Fimognari, Lorenzo; Sakuragi, Yumiko

2017-01-01

Microalga-based biomanufacturing of recombinant proteins is attracting growing attention due to its advantages in safety, metabolic diversity, scalability and sustainability. Secretion of recombinant proteins can accelerate the use of microalgal platforms by allowing post......-translational modifications and easy recovery of products from the culture media. However, currently, the yields of secreted recombinant proteins are low, which hampers the commercial application of this strategy. This study aimed at expanding the genetic tools for enhancing secretion of recombinant proteins in Chlamydomonas...... in the endoplasmic reticulum (ER). Taken together, the results demonstrate the utility of the gametolysin signal sequence and (SP)n glycomodule to promote a more efficient biomanufacturing of microalgae-based recombinant proteins....

Expression of calcium binding protein S100 A7 (psoriasin) in laryngeal carcinoma.

Science.gov (United States)

Tiveron, Rogério Costa; de Freitas, Luiz Carlos Conti; Figueiredo, David L; Serafini, Luciano N; Mamede, Rui Celso Martins; Zago, Marco A

2012-01-01

Many studies have reported increased expression of S100 A7 (psoriasin) in neoplastic lesions. Among them are studies on breast carcinoma, bladder squamous cell carcinoma, skin tumors and oral cavity squamous cell carcinoma. The expression of S100 A7 has not been described for laryngeal cancer. This study aims to identify the expression of the calcium-binding protein S100 A7 and its correlation with squamous cell carcinomas of the larynx. Specimens from 63 patients were submitted to immunohistochemistry testing with antibody S100 A7. Results were classified and compared. The group with highly differentiated tumors had the highest treatment failure scores. Moderately differentiated tumors had higher treatment failure scores than poorly differentiated tumors. Higher scores were predominantly seen on stages I and II in moderately differentiated tumors, whereas score distribution was more homogeneous in advanced stage disease (III and IV). Regarding failure in treatment, the group scoring zero (3/4 complications: 75%) differed significantly from the remaining groups (13/59: 22%). S100 A7 marker was expressed in 93.7% of laryngeal cancer cases, with higher positive correlation rates in more differentiated tumors and significantly lower rates of treatment failure. Scores had no impact on survival rates.

Expression of microphthalmia transcription factor, S100 protein, and HMB-45 in malignant melanoma and pigmented nevi.

Science.gov (United States)

Xia, Jianxin; Wang, Yanlong; Li, Fuqiu; Wang, Jinfeng; Mu, Yan; Mei, Xianglin; Li, Xue; Zhu, Wenjing; Jin, Xianhua; Yu, Kai

2016-09-01

Malignant melanoma (MM) is a type of malignant tumor, which originates from neural crest melanocytes. MM progresses rapidly and results in a high mortality rate. The present study aims to investigate the expression of microphthalmia transcription factor (MITF), the S100 protein, and HMB-45 in MM and pigmented nevi. A total of 32 MM samples (including three skin metastasis, three lymph node metastasis and two spindle cell MM samples), two Spitz nevus samples, four pigmented nevus samples and two blue nevus samples were collected. The expression levels of S100 protein, HMB-45, and MITF were observed via immunostaining. The S100 protein exhibited high positive rates in MM and pigment disorders (96.7 and 100%, respectively), but with low specificity. The S100 protein was also expressed in fibroblasts, myoepithelial cells, histocytes and Langerhans cells in normal skin samples. HMB-45 had high specificity. Its positive expression was only confined to MM cells and junctional nevus cells. Furthermore, HMB-45 was not expressed in melanocytes in the normal tissue samples around the tumor or in the benign intradermal nevus cells. MITF exhibited high specificity and high sensitivity. It was expressed in the nuclei of melanocytes, MM cells and nevus cells. It was observed to be strongly expressed in metastatic MM and spindle cell MMs. Thus, MITF may present as a specific immunomarker for the diagnosis and differential diagnosis of MM.

Immunization against Rumen Methanogenesis by Vaccination with a New Recombinant Protein.

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Litai Zhang

Full Text Available Vaccination through recombinant proteins against rumen methanogenesis provides a mitigation approach to reduce enteric methane (CH4 emissions in ruminants. The objective of present study was to evaluate the in vivo efficacy of a new vaccine candidate protein (EhaF on methanogenesis and microbial population in the rumen of goats. We amplified the gene mru 1407 encoding protein EhaF using fresh rumen fluid samples of mature goats and successfully expressed recombinant protein (EhaF in Escherichia coli Rosetta. This product was evaluated using 12 mature goats with half for control and other half injected with 400ug/goat the purified recombinant protein in day 1 and two subsequent booster immunizations in day 35 and 49. All measurements were undertaken from 63 to 68 days after the initial vaccination, with CH4 emissions determined using respiration calorimeter chambers. The results showed that the vaccination caused intensive immune responses in serum and saliva, although it had no significant effect on total enteric CH4 emissions and methanogen population in the rumen, when compared with the control goats. However, the vaccination altered the composition of rumen bacteria, especially the abundance of main phylum Firmicutes and genus Prevotella. The results indicate that protein EhaF might not be an effective vaccine to reduce enteric CH4 emissions but our vaccine have potential to influence the rumen ecosystem of goats.

The level of neuron-specific enolase and S-100 protein in the cerebrospinal fluid of patients with acute bacterial meningitis

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A. V. Sokhan

2016-08-01

Full Text Available Aim. To evaluate the diagnostic and prognostic role of neuron-specific enolase (NSE and S-100 protein levels in cerebrospinal fluid (CSF of patients with acute bacterial meningitis in the course of the disease. Materials and Methods. 54 cases of acute bacterial meningitis were analyzed, among them – 26 with pneumococcal and 28 with meningococcal etiology. Patients were divided into groups depending on the severity and etiology of disease. In addition to routine laboratory methods, we analyzed the CSF levels of S-100 protein and NSE at admission and after 10 – 12 days of treatment. 12 patients with acute respiratory infections and meningism were examined as a comparison group. Results. In all patients with acute bacterial meningitis CSF NSE and protein S-100 levels were significantly higher than in the control group (P <0,05. CSF neuro specific proteins level was in direct dependence on severity of the disease, and in patients with severe disease was significantly higher than in patients with moderate severity and in the control group (P <0,01. After 10 – 12 days of treatment, the level of the NSE and S-100 protein decreased, but in severe cases was still higher than in the control group (P <0,05. Conclusions. Increased cerebrospinal fluid NSE and S – 100 protein levels shows the presence and value of neurons and glial cells damage in patients with acute bacterial meningitis. CSF S-100 protein and neuron-specific enolase levels help to determine the severity of neurons destruction and glial cells in patients with acute bacterial meningitis. Level of neurospecific protein is in direct proportion to the severity of the disease and is the highest in patients with severe cases (P<0,05. It confirms the diagnostic and prognostic value of CSF neurospecific protein determination in patients with bacterial meningitis.

Expression and purification of recombinant polyomavirus VP2 protein and its interactions with polyomavirus proteins

Science.gov (United States)

Cai, X.; Chang, D.; Rottinghaus, S.; Consigli, R. A.; Spooner, B. S. (Principal Investigator)

1994-01-01

Recombinant polyomavirus VP2 protein was expressed in Escherichia coli (RK1448), using the recombinant expression system pFPYV2. Recombinant VP2 was purified to near homogeneity by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, electroelution, and Extracti-Gel chromatography. Polyclonal serum to this protein which reacted specifically with recombinant VP2 as well as polyomavirus virion VP2 and VP3 on Western blots (immunoblots) was produced. Purified VP2 was used to establish an in vitro protein-protein interaction assay with polyomavirus structural proteins and purified recombinant VP1. Recombinant VP2 interacted with recombinant VP1, virion VP1, and the four virion histones. Recombinant VP1 coimmunoprecipitated with recombinant VP2 or truncated VP2 (delta C12VP2), which lacked the carboxy-terminal 12 amino acids. These experiments confirmed the interaction between VP1 and VP2 and revealed that the carboxyterminal 12 amino acids of VP2 and VP3 were not necessary for formation of this interaction. In vivo VP1-VP2 interaction study accomplished by cotransfection of COS-7 cells with VP2 and truncated VP1 (delta N11VP1) lacking the nuclear localization signal demonstrated that VP2 was capable of translocating delta N11VP1 into the nucleus. These studies suggest that complexes of VP1 and VP2 may be formed in the cytoplasm and cotransported to the nucleus for virion assembly to occur.

Targeted in vivo inhibition of specific protein-protein interactions using recombinant antibodies.

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Matej Zábrady

Full Text Available With the growing availability of genomic sequence information, there is an increasing need for gene function analysis. Antibody-mediated "silencing" represents an intriguing alternative for the precise inhibition of a particular function of biomolecules. Here, we describe a method for selecting recombinant antibodies with a specific purpose in mind, which is to inhibit intrinsic protein-protein interactions in the cytosol of plant cells. Experimental procedures were designed for conveniently evaluating desired properties of recombinant antibodies in consecutive steps. Our selection method was successfully used to develop a recombinant antibody inhibiting the interaction of ARABIDOPSIS HISTIDINE PHOSPHOTRANSFER PROTEIN 3 with such of its upstream interaction partners as the receiver domain of CYTOKININ INDEPENDENT HISTIDINE KINASE 1. The specific down-regulation of the cytokinin signaling pathway in vivo demonstrates the validity of our approach. This selection method can serve as a prototype for developing unique recombinant antibodies able to interfere with virtually any biomolecule in the living cell.

A new tagging system for production of recombinant proteins in Drosophila S2 cells using the third domain of the urokinase receptor

DEFF Research Database (Denmark)

Gårdsvoll, Henrik; Hansen, Line V; Jørgensen, Thomas J D

2007-01-01

The use of protein fusion tag technology greatly facilitates detection, expression and purification of recombinant proteins, and the demands for new and more effective systems are therefore expanding. We have used a soluble truncated form of the third domain of the urokinase receptor...... as a convenient C-terminal fusion partner for various recombinant extracellular human proteins used in basic cancer research. The stability of this cystein-rich domain, which structure adopts a three-finger fold, provides an important asset for its applicability as a fusion tag for expression of recombinant...... chromatography procedure using the immobilized anti-uPAR monoclonal antibody R2. An optional enterokinase cleavage site is included between the various recombinant proteins and the linker region of the tag, which enables generation of highly pure preparations of tag-free recombinant proteins. Using this system...

Nuclear Engineering of Microalgae for High Yield Secretion of Recombinant Proteins

DEFF Research Database (Denmark)

Ramos Martinez, Erick Miguel

biotechnology hosts including safety, metabolic diversity, scalability, sustainability and low production cost. Over the past decades, considerable improvement has been made to express and secrete recombinant proteins in high levels: however current yields are still low. The first research project presented...... to the glycomodules, accumulation of a fusion protein was dramatically increased by up to 12 folds, with the maximum yield of 15 mg L-1. Characterization of the secreted Venus showed the presence of glycosylations and increased resistance to proteolytic degradation. The results from this thesis demonstrate...... the potential of microalgae as a cell factory for secretion of recombinant proteins. The second research project presented in this thesis aimed to establish a new robust method to allow in vivo measurements of metabolic enzyme activities in cyanobacteria, with a hope that the method would facilitate further...

Expression and purification of recombinant proteins in Escherichia coli tagged with a small metal-binding protein from Nitrosomonas europaea.

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Vargas-Cortez, Teresa; Morones-Ramirez, Jose Ruben; Balderas-Renteria, Isaias; Zarate, Xristo

2016-02-01

Escherichia coli is still the preferred organism for large-scale production of recombinant proteins. The use of fusion proteins has helped considerably in enhancing the solubility of heterologous proteins and their purification with affinity chromatography. Here, the use of a small metal-binding protein (SmbP) from Nitrosomonas europaea is described as a new fusion protein for protein expression and purification in E. coli. Fluorescent proteins tagged at the N-terminal with SmbP showed high levels of solubility, compared with those of maltose-binding protein and glutathione S-transferase, and low formation of inclusion bodies. Using commercially available IMAC resins charged with Ni(II), highly pure recombinant proteins were obtained after just one chromatography step. Proteins may be purified from the periplasm of E. coli if SmbP contains the signal sequence at the N-terminal. After removal of the SmbP tag from the protein of interest, high-yields are obtained since SmbP is a protein of just 9.9 kDa. The results here obtained suggest that SmbP is a good alternative as a fusion protein/affinity tag for the production of soluble recombinant proteins in E. coli. Copyright © 2015 Elsevier Inc. All rights reserved.

Recombinant HT{sub m4} gene, protein and assays

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Lim, B.; Adra, C.N.; Lelias, J.M.

1996-09-03

The invention relates to a recombinant DNA molecule which encodes a HT{sub m4} protein, a transformed host cell which has been stably transfected with a DNA molecule which encodes a HT{sub m4} protein and a recombinant HT{sub m4} protein. The invention also relates to a method for detecting the presence of a hereditary atopy. 2 figs.

Day/night changes in serum S100B protein concentrations in acute paranoid schizophrenia.

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Morera-Fumero, Armando L; Díaz-Mesa, Estefanía; Abreu-Gonzalez, Pedro; Fernandez-Lopez, Lourdes; Cejas-Mendez, Maria Del Rosario

2017-04-03

There are day/night and seasonal changes in biological markers such as melatonin and cortisol. Controversial changes in serum S100B protein levels have been described in schizophrenia. We aim studying whether serum S100B levels present day/night variations in schizophrenia patients and whether S100B levels are related to psychopathology. Sixty-five paranoid schizophrenic inpatients participated in the study. Psychopathology was assessed with the Positive and Negative Syndrome Scale (PANSS) at admission and discharge. Blood was drawn at 12:00 (midday) and 00:00 (midnight) hours at admission and discharge. Sixty-five healthy subjects matched by age, gender and season acted as control group. At admission and discharge patients had significantly higher serum S100B concentrations at midday and midnight than healthy subjects. At admission, patients showed a day/night variation of S100B levels, with higher S100B levels at 12:00 than at 00:00h (143.7±26.3pg/ml vs. 96.9±16.6pg/ml). This day/night difference was not present in the control group. Midday and midnight S100B at admission decreased when compared to S100B at discharge (midday, 143.7±26.3 vs. 83.0±12, midnight 96.9±16.6 vs. 68.6±14.5). There was a positive correlation between the PANSS positive subscale and S100B concentrations at admission. This correlation was not present at discharge. acute paranoid schizophrenia inpatients present a day/night change of S100B serum levels at admission that disappears at discharge. The correlation between serum S100B concentrations and the PANSS positive scores at admission as well as the decrease of S100B at discharge may be interpreted as an acute biological response to the clinical state of the patients. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Protection by recombinant viral proteins against a respiratory challenge with virulent avian metapneumovirus.

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Chary, Parag; Njenga, M Kariuki; Sharma, Jagdev M

2005-12-15

Protection by recombinant avian metapneumovirus (aMPV) N or M proteins against a respiratory challenge with virulent aMPV was examined. N, M or N+M proteins were administered intramuscularly (IM) with incomplete Freund's adjuvant (IFA) or by the oculonasal (ON) route with cholera toxin-B (CTB). Each turkey received 40 or 80 microg of each recombinant protein. Birds were considered protected against challenge if the challenge virus was not detectable in the choanal swabs by RT-PCR. At a dose of 40 microg/bird, N protein given with IFA by the IM route protected eight out of nine birds. M protein at the same dose protected three out of seven birds, while a combination of N+M proteins (40 microg each) protected three out of four birds. At a dose of 80 microg of each of N and M proteins per bird given with IFA by the IM route, 100% protection was achieved. ON immunization with a mixture of N and M proteins induced partial protection when the proteins were given with CTB; no detectable protection was noted without CTB. N and M proteins induced anti-aMPV antibodies, although protection against virulent virus challenge did not appear to be associated with the level or presence of antibodies.

Transient Expression and Cellular Localization of Recombinant Proteins in Cultured Insect Cells.

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Fabrick, Jeffrey A; Hull, J Joe

2017-04-20

Heterologous protein expression systems are used for the production of recombinant proteins, the interpretation of cellular trafficking/localization, and the determination of the biochemical function of proteins at the sub-organismal level. Although baculovirus expression systems are increasingly used for protein production in numerous biotechnological, pharmaceutical, and industrial applications, nonlytic systems that do not involve viral infection have clear benefits but are often overlooked and underutilized. Here, we describe a method for generating nonlytic expression vectors and transient recombinant protein expression. This protocol allows for the efficient cellular localization of recombinant proteins and can be used to rapidly discern protein trafficking within the cell. We show the expression of four recombinant proteins in a commercially available insect cell line, including two aquaporin proteins from the insect Bemisia tabaci, as well as subcellular marker proteins specific for the cell plasma membrane and for intracellular lysosomes. All recombinant proteins were produced as chimeras with fluorescent protein markers at their carboxyl termini, which allows for the direct detection of the recombinant proteins. The double transfection of cells with plasmids harboring constructs for the genes of interest and a known subcellular marker allows for live cell imaging and improved validation of cellular protein localization.

Subdominant Outer Membrane Antigens in Anaplasma marginale: Conservation, Antigenicity, and Protective Capacity Using Recombinant Protein.

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Deirdre R Ducken

Full Text Available Anaplasma marginale is a tick-borne rickettsial pathogen of cattle with a worldwide distribution. Currently a safe and efficacious vaccine is unavailable. Outer membrane protein (OMP extracts or a defined surface protein complex reproducibly induce protective immunity. However, there are several knowledge gaps limiting progress in vaccine development. First, are these OMPs conserved among the diversity of A. marginale strains circulating in endemic regions? Second, are the most highly conserved outer membrane proteins in the immunogens recognized by immunized and protected animals? Lastly, can this subset of OMPs recognized by antibody from protected vaccinates and conserved among strains recapitulate the protection of outer membrane vaccines? To address the first goal, genes encoding OMPs AM202, AM368, AM854, AM936, AM1041, and AM1096, major subdominant components of the outer membrane, were cloned and sequenced from geographically diverse strains and isolates. AM202, AM936, AM854, and AM1096 share 99.9 to 100% amino acid identity. AM1041 has 97.1 to 100% and AM368 has 98.3 to 99.9% amino acid identity. While all four of the most highly conserved OMPs were recognized by IgG from animals immunized with outer membranes, linked surface protein complexes, or unlinked surface protein complexes and shown to be protected from challenge, the highest titers and consistent recognition among vaccinates were to AM854 and AM936. Consequently, animals were immunized with recombinant AM854 and AM936 and challenged. Recombinant vaccinates and purified outer membrane vaccinates had similar IgG and IgG2 responses to both proteins. However, the recombinant vaccinates developed higher bacteremia after challenge as compared to adjuvant-only controls and outer membrane vaccinates. These results provide the first evidence that vaccination with specific antigens may exacerbate disease. Progressing from the protective capacity of outer membrane formulations to

N-terminal processing of affinity-tagged recombinant proteins purified by IMAC procedures.

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Mooney, Jane T; Fredericks, Dale P; Christensen, Thorkild; Bruun Schiødt, Christine; Hearn, Milton T W

2015-07-01

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. Copyright © 2015 John Wiley & Sons, Ltd.

Expression and characterization of highly antigenic domains of chicken anemia virus viral VP2 and VP3 subunit proteins in a recombinant E. coli for sero-diagnostic applications

Science.gov (United States)

2013-01-01

subunit proteins. Moreover, the VP2-396N and VP2-345 based ELISAs had better sensitivity (97.5%) and excellent specificity (100%) during serodiagnosis testing using a mean plus three standard deviations cut-off. The VP3-246M based ELISA showed a sensitivity of 85% and a specificity of 100% at the same cut-off value. Conclusions This is the first report to systematically assess the antigenic characteristics of CAV viral proteins for sero-diagnosis purposes. Purified recombinant VP2-396N and VP2-345N subunit proteins, which span defined regions of VP2, were demonstrated to have good antigenicity and higher sensitivities than VP3-246M and were able to recognize CAV-positive chicken serum using an ELISA assay. The defined antigenicity potential of these chimeric subunit proteins produced by expression in E. coli seem to have potential and could be useful in the future for the development of the CAV diagnostic tests based on a subunit protein ELISA system. PMID:23937712

Secretion of S100A8, S100A9, and S100A12 by Neutrophils Involves Reactive Oxygen Species and Potassium Efflux

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Mélanie R. Tardif

2015-01-01

Full Text Available S100A8/A9 (calprotectin and S100A12 proinflammatory mediators are found at inflammatory sites and in the serum of patients with inflammatory or autoimmune diseases. These cytoplasmic proteins are secreted by neutrophils at sites of inflammation via alternative secretion pathways of which little is known. This study examined the nature of the stimuli leading to S100A8/A9 and S100A12 secretion as well as the mechanism involved in this alternative secretion pathway. Chemotactic agents, cytokines, and particulate molecules were used to stimulate human neutrophils. MSU crystals, PMA, and H2O2 induced the release of S100A8, S100A9, and S100A12 homodimers, as well as S100A8/A9 heterodimer. High concentrations of S100A8/A9 and S100A12 were secreted in response to nanoparticles like MSU, silica, TiO2, fullerene, and single-wall carbon nanotubes as well as in response to microbe-derived molecules, such as zymosan or HKCA. However, neutrophils exposed to the chemotactic factors fMLP failed to secrete S100A8/A9 or S100A12. Secretion of S100A8/A9 was dependent on the production of reactive oxygen species and required K+ exchanges through the ATP-sensitive K+ channel. Altogether, these findings suggest that S100A12 and S100A8/A9 are secreted independently either via distinct mechanisms of secretion or following the activation of different signal transduction pathways.

Trichohyalin-like 1 protein, a member of fused S100 proteins, is expressed in normal and pathologic human skin

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Yamakoshi, Takako [Department of Dermatology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama 930-0194 (Japan); Makino, Teruhiko, E-mail: tmakino@med.u-toyama.ac.jp [Department of Dermatology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama 930-0194 (Japan); Ur Rehman, Mati; Yoshihisa, Yoko [Department of Dermatology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama 930-0194 (Japan); Sugimori, Michiya [Department of Integrative Neuroscience, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama 930-0194 (Japan); Shimizu, Tadamichi, E-mail: shimizut@med.u-toyama.ac.jp [Department of Dermatology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, Toyama 930-0194 (Japan)

2013-03-01

Highlights: ► Trichohyalin-like 1 protein is a member of the fused-type S100 protein gene family. ► Specific antibodies against the C-terminus of the TCHHL1 protein were generated. ► TCHHL1 proteins were expressed in the basal layer of the normal epidermis. ► TCHHL1 proteins were strongly expressed in tumor nests of BCC and SCC. ► The expression of TCHHL1 proteins increased in epidermis of psoriasis vulgaris. - Abstract: Trichohyalin-like 1 (TCHHL1) protein is a novel member of the fused-type S100 protein gene family. The deduced amino acid sequence of TCHHL1 contains an EF-hand domain in the N-terminus, one trans-membrane domain and a nuclear localization signal. We generated specific antibodies against the C-terminus of the TCHHL1 protein and examined the expression of TCHHL1 proteins in normal and pathological human skin. An immunohistochemical study showed that TCHHL1 proteins were expressed in the basal layer of the normal epidermis. In addition, signals of TCHHL1 proteins were observed around the nuclei of cultured growing keratinocytes. Accordingly, TCHHL1 mRNA has been detected in normal skin and cultured growing keratinocytes. Furthermore, TCHHL1 proteins were strongly expressed in the peripheral areas of tumor nests in basal cell carcinomas and squamous cell carcinomas. A dramatic increase in the number of Ki67 positive cells was observed in TCHHL1-expressing areas. The expression of TCHHL1 proteins also increased in non-cancerous hyperproliferative epidermal tissues such as those of psoriasis vulgaris and lichen planus. These findings highlight the possibility that TCHHL1 proteins are expressed in growing keratinocytes of the epidermis and might be associated with the proliferation of keratinocytes.

Trichohyalin-like 1 protein, a member of fused S100 proteins, is expressed in normal and pathologic human skin

International Nuclear Information System (INIS)

Yamakoshi, Takako; Makino, Teruhiko; Ur Rehman, Mati; Yoshihisa, Yoko; Sugimori, Michiya; Shimizu, Tadamichi

2013-01-01

Highlights: ► Trichohyalin-like 1 protein is a member of the fused-type S100 protein gene family. ► Specific antibodies against the C-terminus of the TCHHL1 protein were generated. ► TCHHL1 proteins were expressed in the basal layer of the normal epidermis. ► TCHHL1 proteins were strongly expressed in tumor nests of BCC and SCC. ► The expression of TCHHL1 proteins increased in epidermis of psoriasis vulgaris. - Abstract: Trichohyalin-like 1 (TCHHL1) protein is a novel member of the fused-type S100 protein gene family. The deduced amino acid sequence of TCHHL1 contains an EF-hand domain in the N-terminus, one trans-membrane domain and a nuclear localization signal. We generated specific antibodies against the C-terminus of the TCHHL1 protein and examined the expression of TCHHL1 proteins in normal and pathological human skin. An immunohistochemical study showed that TCHHL1 proteins were expressed in the basal layer of the normal epidermis. In addition, signals of TCHHL1 proteins were observed around the nuclei of cultured growing keratinocytes. Accordingly, TCHHL1 mRNA has been detected in normal skin and cultured growing keratinocytes. Furthermore, TCHHL1 proteins were strongly expressed in the peripheral areas of tumor nests in basal cell carcinomas and squamous cell carcinomas. A dramatic increase in the number of Ki67 positive cells was observed in TCHHL1-expressing areas. The expression of TCHHL1 proteins also increased in non-cancerous hyperproliferative epidermal tissues such as those of psoriasis vulgaris and lichen planus. These findings highlight the possibility that TCHHL1 proteins are expressed in growing keratinocytes of the epidermis and might be associated with the proliferation of keratinocytes

Oxidative stress and S-100B protein in children with bacterial meningitis

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Hamed Enas A

2009-10-01

Full Text Available Abstract Background Bacterial meningitis is often associated with cerebral compromise which may be responsible for neurological sequelae in nearly half of the survivors. Little is known about the mechanisms of CNS involvement in bacterial meningitis. Several studies have provided substantial evidence for the key role of nitric oxide (NO and reactive oxygen species in the complex pathophysiology of bacterial meningitis. Methods In the present study, serum and CSF levels of NO, lipid peroxide (LPO (mediators for oxidative stress and lipid peroxidation; total thiol, superoxide dismutase (SOD (antioxidant mediators and S-100B protein (mediator of astrocytes activation and injury, were investigated in children with bacterial meningitis (n = 40. Albumin ratio (CSF/serum is a marker of blood-CSF barriers integrity, while mediator index (mediator ratio/albumin ratio is indicative of intrathecal synthesis. Results Compared to normal children (n = 20, patients had lower serum albumin but higher NO, LPO, total thiol, SOD and S-100B. The ratios and indices of NO and LPO indicate blood-CSF barriers dysfunction, while the ratio of S-100B indicates intrathecal synthesis. Changes were marked among patients with positive culture and those with neurological complications. Positive correlation was found between NO index with CSF WBCs (r = 0.319, p Conclusion This study suggests that loss of integrity of brain-CSF barriers, oxidative stress and S-100B may contribute to the severity and neurological complications of bacterial meningitis.

Limiting factors in Escherichia colifed-batch production of recombinant proteins

DEFF Research Database (Denmark)

Sanden, A.M.; Prytz, I.; Tubelekas, I.

2003-01-01

recombinant protein production, fed-batch, specific growth rate, feed profile, induction, mRNA, transcription, translation, acetic acid formation......recombinant protein production, fed-batch, specific growth rate, feed profile, induction, mRNA, transcription, translation, acetic acid formation...

Serum S100B: A possible biomarker for severity of obstructive sleep apnea

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Eman Riad

2017-10-01

Conclusion: Serum S100B protein was significantly elevated in OSA patients and its serum levels correlated with the severity of the disease. Increased serum S100B could indicat brain injury and could be a potential serum biomarker for detection of early neurological complications in OSA patients that could improve the management and care of these patients.

[Eukaryotic Expression and Immunogenic Research of Recombination Ebola Virus Membrane Protein Gp-Fc].

Science.gov (United States)

Zhang, Xiaoguang; Yang, Ren; Wang, Jiao; Wang, Xuan; Hou, Mieling; An, Lina; Zhu, Ying; Cao, Yuxi; Zeng, Yi

2016-01-01

We used 293 cells to express the recombinant membrane protein of the Ebola virus. Then, the immunogenicity of the recombinant protein was studied by immunized BALB/c mice. According to the codon use frequency of humans, the gene encoding the extracellular domain of the Ebola virus membrane protein was optimized, synthesized, and inserted into the eukaryotic expression plasmid pXG-Fc to construct the human IgG Fc and Ebola GP fusion protein expression plasmid pXG-modGP-Fc. To achieve expression, the fusion protein expression vector was transfected into high-density 293 cells using transient transfection technology. The recombinant protein was purified by protein A affinity chromatography. BALB/c mice were immunized with the purified fusion protein, and serum antibody titers evaluated by an indirect enzyme-linked immunosorbent assay (ELISA). Purification and analyses of the protein revealed that the eukaryotic expression vector could express the recombinant protein GP-Fc effectively, and that the recombinant protein in the supernatant of the cell culture was present as a dimer. After immunization with the purified recombinant protein, a high titer of antigen-specific IgG could be detected in the serum of immunized mice by indirect ELISA, showing that the recombinant protein had good immunogenicity. These data suggest that we obtained a recombinant protein with good immunogenicity. Our study is the basis for development of a vaccine against the Ebola virus and for screening of monoclonal antibodies.

Efficient secretory expression of recombinant proteins in Escherichia coli with a novel actinomycete signal peptide.

Science.gov (United States)

Cui, Yanbing; Meng, Yiwei; Zhang, Juan; Cheng, Bin; Yin, Huijia; Gao, Chao; Xu, Ping; Yang, Chunyu

2017-01-01

In well-established heterologous hosts, such as Escherichia coli, recombinant proteins are usually intracellular and frequently found as inclusion bodies-especially proteins possessing high rare codon content. In this study, successful secretory expression of three hydrolases, in a constructed inducible or constitutive system, was achieved by fusion with a novel signal peptide (Kp-SP) from an actinomycete. The signal peptide efficiently enabled extracellular protein secretion and also contributed to the active expression of the intracellular recombinant proteins. The thermophilic α-amylase gene of Bacillus licheniformis was fused with Kp-SP. Both recombinants, carrying inducible and constitutive plasmids, showed remarkable increases in extracellular and intracellular amylolytic activity. Amylase activity was observed to be > 10-fold in recombinant cultures with the constitutive plasmid, pBSPPc, compared to that in recombinants lacking Kp-SP. Further, the signal peptide enabled efficient secretion of a thermophilic cellulase into the culture medium, as demonstrated by larger halo zones and increased enzymatic activities detected in both constructs from different plasmids. For heterologous proteins with a high proportion of rare codons, it is difficult to obtain high expression in E. coli owing to the codon bias. Here, the fusion of an archaeal homologue of the amylase encoding gene, FSA, with Kp-SP resulted in > 5-fold higher extracellular activity. The successful extracellular expression of the amylase indicated that the signal peptide also contributed significantly to its active expression and signified the potential value of this novel and versatile signal peptide in recombinant protein production. Copyright © 2016 Elsevier Inc. All rights reserved.

Serological diagnosis of Strongylus vulgaris infection: use of a recombinant protein

DEFF Research Database (Denmark)

Andersen, Ulla Vestergaard; Howe, Daniel K.; Olsen, Susanne Nautrup

, an immunoreactive cDNA clone was subcloned into E. coli and the plasmid sequenced, the open reading frame encoding the mature protein was cloned into a pET22b expression vector and expressed as a His-tagged recombinant protein in BL21 expression cells. The recombinant protein was used in an indirect enzyme....... vulgaris (n=9) reacted against the recombinant protein, expressed as optic density (OD) readings of >24 % of a positive control, while sera from negative horses had OD readings

Trends in recombinant protein use in animal production.

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Gifre, Laia; Arís, Anna; Bach, Àlex; Garcia-Fruitós, Elena

2017-03-04

Recombinant technologies have made possible the production of a broad catalogue of proteins of interest, including those used for animal production. The most widely studied proteins for the animal sector are those with an important role in reproduction, feed efficiency, and health. Nowadays, mammalian cells and fungi are the preferred choice for recombinant production of hormones for reproductive purposes and fibrolytic enzymes to enhance animal performance, respectively. However, the development of low-cost products is a priority, particularly in livestock. The study of cell factories such as yeast and bacteria has notably increased in the last decades to make the new developed reproductive hormones and fibrolytic enzymes a real alternative to the marketed ones. Important efforts have also been invested to developing new recombinant strategies for prevention and therapy, including passive immunization and modulation of the immune system. This offers the possibility to reduce the use of antibiotics by controlling physiological processes and improve the efficacy of preventing infections. Thus, nowadays different recombinant fibrolytic enzymes, hormones, and therapeutic molecules with optimized properties have been successfully produced through cost-effective processes using microbial cell factories. However, despite the important achievements for reducing protein production expenses, alternative strategies to further reduce these costs are still required. In this context, it is necessary to make a giant leap towards the use of novel strategies, such as nanotechnology, that combined with recombinant technology would make recombinant molecules affordable for animal industry.

Purification of inclusion bodies using PEG precipitation under denaturing conditions to produce recombinant therapeutic proteins from Escherichia coli.

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Chen, Huanhuan; Li, Ninghuan; Xie, Yueqing; Jiang, Hua; Yang, Xiaoyi; Cagliero, Cedric; Shi, Siwei; Zhu, Chencen; Luo, Han; Chen, Junsheng; Zhang, Lei; Zhao, Menglin; Feng, Lei; Lu, Huili; Zhu, Jianwei

2017-07-01

It has been documented that the purification of inclusion bodies from Escherichia coli by size exclusion chromatography (SEC) may benefit subsequent refolding and recovery of recombinant proteins. However, loading volume and the high cost of the column limits its application in large-scale manufacturing of biopharmaceutical proteins. We report a novel process using polyethylene glycol (PEG) precipitation under denaturing conditions to replace SEC for rapid purification of inclusion bodies containing recombinant therapeutic proteins. Using recombinant human interleukin 15 (rhIL-15) as an example, inclusion bodies of rhIL-15 were solubilized in 7 M guanidine hydrochloride, and rhIL-15 was precipitated by the addition of PEG 6000. A final concentration of 5% (w/v) PEG 6000 was found to be optimal to precipitate target proteins and enhance recovery and purity. Compared to the previously reported S-200 size exclusion purification method, PEG precipitation was easier to scale up and achieved the same protein yields and quality of the product. PEG precipitation also reduced manufacturing time by about 50 and 95% of material costs. After refolding and further purification, the rhIL-15 product was highly pure and demonstrated a comparable bioactivity with a rhIL-15 reference standard. Our studies demonstrated that PEG precipitation of inclusion bodies under denaturing conditions holds significant potential as a manufacturing process for biopharmaceuticals from E. coli protein expression systems.

The role of S100 genes in breast cancer progression.

LENUS (Irish Health Repository)

McKiernan, Eadaoin

2012-02-01

The S100 gene family encode low molecular weight proteins implicated in cancer progression. In this study, we analyzed the expression of four S100 genes in one cohort of patients with breast cancer and 16 S100 genes in a second cohort. In both cohorts, the expression of S100A8 and S1009 mRNA level was elevated in high-grade compared to low-grade tumors and in estrogen receptor-negative compared to estrogen receptor-positive tumors. None of the S100 transcripts investigated were significantly associated with the presence of lymph node metastasis. Notably, multiple S100 genes, including S100A1, S100A2, S100A4, S100A6, S100A8, S100A9, S100A10, S100A11, and S100A14 were upregulated in basal-type breast cancers compared to non-basal types. Using Spearman\\'s correlation analysis, several S100 transcripts correlated significantly with each other, the strongest correlation has been found between S100A8 and S100A9 (r = 0.889, P < 0.001, n = 295). Of the 16 S100 transcripts investigated, only S100A11 and S100A14 were significantly associated with patient outcome. Indeed, these two transcripts predicted outcome in the cohort of patients that did not receive systemic adjuvant therapy. Based on our findings, we conclude that the different S100 genes play varying roles in breast cancer progression. Specific S100 genes are potential targets for the treatment of basal-type breast cancers.

The role of S100 genes in breast cancer progression.

LENUS (Irish Health Repository)

McKiernan, Eadaoin

2011-06-01

The S100 gene family encode low molecular weight proteins implicated in cancer progression. In this study, we analyzed the expression of four S100 genes in one cohort of patients with breast cancer and 16 S100 genes in a second cohort. In both cohorts, the expression of S100A8 and S1009 mRNA level was elevated in high-grade compared to low-grade tumors and in estrogen receptor-negative compared to estrogen receptor-positive tumors. None of the S100 transcripts investigated were significantly associated with the presence of lymph node metastasis. Notably, multiple S100 genes, including S100A1, S100A2, S100A4, S100A6, S100A8, S100A9, S100A10, S100A11, and S100A14 were upregulated in basal-type breast cancers compared to non-basal types. Using Spearman\\'s correlation analysis, several S100 transcripts correlated significantly with each other, the strongest correlation has been found between S100A8 and S100A9 (r = 0.889, P < 0.001, n = 295). Of the 16 S100 transcripts investigated, only S100A11 and S100A14 were significantly associated with patient outcome. Indeed, these two transcripts predicted outcome in the cohort of patients that did not receive systemic adjuvant therapy. Based on our findings, we conclude that the different S100 genes play varying roles in breast cancer progression. Specific S100 genes are potential targets for the treatment of basal-type breast cancers.

Influenza vaccines: from whole virus preparations to recombinant protein technology.

Science.gov (United States)

Huber, Victor C

2014-01-01

Vaccination against influenza represents our most effective form of prevention. Historical approaches toward vaccine creation and production have yielded highly effective vaccines that are safe and immunogenic. Despite their effectiveness, these historical approaches do not allow for the incorporation of changes into the vaccine in a timely manner. In 2013, a recombinant protein-based vaccine that induces immunity toward the influenza virus hemagglutinin was approved for use in the USA. This vaccine represents the first approved vaccine formulation that does not require an influenza virus intermediate for production. This review presents a brief history of influenza vaccines, with insight into the potential future application of vaccines generated using recombinant technology.

The use of an in vitro microneutralization assay to evaluate the potential of recombinant VP5 protein as an antigen for vaccinating against Grass carp reovirus

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Xu Dan

2011-03-01

Full Text Available Abstract Background Grass carp reovirus (GCRV is the causative pathogen of grass carp hemorrhagic disease, one of the major diseases damaging grass carp Ctenopharyngon idellus breeding industry in China. Prevention and control of the disease is impeded largely due to the lack of research in economic subunit vaccine development. This study aimed to evaluate the potential of viral outer shell protein VP5 as subunit vaccine. Methods The vp5 gene was isolated from the viral genome through RT-PCR and genetically engineered to express the recombinant VP5 protein in E coli. The viral origin of the recombinant protein was confirmed by Western blot analysis with a monoclonal antibody against viral VP5 protein. Polyclonal antibody against the recombinant VP5 protein was prepared from mice. A microneutralization assay was developed to test its neutralizing ability against GCRV infection in cell culture. Results The GST-VP5 fusion protein (rVP5 was produced from E. Coli with expected molecular weight of 90 kDa. The protein was purified and employed to prepare anti-VP5 polyclonal antibody from mice. The anti-VP5 antibody was found to neutralize GCRV through in vitro microneutralization assay and viral progeny quantification analysis. Conclusions The present study showed that the viral VP5 protein was involved in viral infection and bacterially-expressed VP5 could be suitable for developing subunit vaccine for the control of GCRV infection.

Vaccine potential of recombinant saposin-like protein 2 against Fasciolosis gigantica in mice.

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Kueakhai, Pornanan; Changklungmoa, Narin; Riengrojpitak, Suda; Chaichanasak, Pannigan; Meemon, Krai; Chaithirayanon, Kulathida; Chantree, Pathanin; Sansri, Veerawat; Itagaki, Tadashi; Sobhon, Prasert

2013-11-12

Saposin-like protein 2 (SAP-2) is a protein that adult of Fasciola spp. use to lyse plasma membrane of red blood cells, so that their contents can be digested by proteases for the parasites' nutrients. Thus SAP-2 is a plausible target for vaccination against these parasites. Recombinant Fasciola gigantica saposin-like protein 2 (rFgSAP-2) was expressed in Escherichia coli BL21 (DE3). A vaccination was performed in ICR mice (n=10) by subcutaneous injection with 50μg of rFgSAP-2 combined with Freund's adjuvant. At 2 weeks after the second boost, mice were infected with 30 F. gigantica metacercariae by oral route. The percentages of protection of rFgSAP-2 vaccine against F. gigantica were estimated to be 76.4-78.5% when compared with non vaccinated-infected and adjuvant-infected controls, respectively. The antibodies in immune sera of vaccinated mice were shown by immuno-blotting to react with native FgSAP-2 in the extract of 2- and 4-week-old juvenile parasites. By determining the levels of IgG1 and IgG2a in the immune sera, which are indicative of Th2 and Th1 immune responses, it was found that both Th1 and Th2 humoral immune response were significantly increased in rFgSAP-2 immunized group compared with the control groups, with higher levels of Th2 (IgG1) than Th1 (IgG2a). The levels of serum aspartate aminotransferase (AST) and alanine transaminase (ALT) in rFgSAP-2-immunized group showed no significant difference from those of the non-immunized and infected group, indicating that early juvenile parasites induced liver parenchyma damage, even though the numbers of worm recoveries were significantly different. This study indicates that rFgSAP-2 has a high potential as a vaccine candidate against F. gigantica in mice, and this potential will be tested in larger economic animals. Copyright © 2013 Elsevier Ltd. All rights reserved.

Expression and the antigenicity of recombinant coat proteins of tungro viruses expressed in Escherichia coli.

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Yee, Siew Fung; Chu, Chia Huay; Poili, Evenni; Sum, Magdline Sia Henry

2017-02-01

Rice tungro disease (RTD) is a recurring disease affecting rice farming especially in the South and Southeast Asia. The disease is commonly diagnosed by visual observation of the symptoms on diseased plants in paddy fields and by polymerase chain reaction (PCR). However, visual observation is unreliable and PCR can be costly. High-throughput as well as relatively cheap detection methods are important for RTD management for screening large number of samples. Due to this, detection by serological assays such as immunoblotting assays and enzyme-linked immunosorbent assay are preferred. However, these serological assays are limited by lack of continuous supply of antibodies as reagents due to the difficulty in preparing sufficient purified virions as antigens. This study aimed to generate and evaluate the reactivity of the recombinant coat proteins of Rice tungro bacilliform virus (RTBV) and Rice tungro spherical virus (RTSV) as alternative antigens to generate antibodies. The genes encoding the coat proteins of both viruses, RTBV (CP), and RTSV (CP1, CP2 and CP3) were cloned and expressed as recombinant fusion proteins in Escherichia coli. All of the recombinant fusion proteins, with the exception of the recombinant fusion protein of the CP2 of RTSV, were reactive against our in-house anti-tungro rabbit serum. In conclusion, our study showed the potential use of the recombinant fusion coat proteins of the tungro viruses as alternative antigens for production of antibodies for diagnostic purposes. Copyright © 2016 Elsevier B.V. All rights reserved.

Immunohistochemical Characterization of S100A6 in the Murine Ovary

International Nuclear Information System (INIS)

Hanaue, Mayu; Miwa, Naofumi; Takamatsu, Ken

2012-01-01

S100 proteins comprise a large family of Ca 2+ -binding proteins and exhibit a variety of intra- and extracellular functions. Despite our growing knowledge about the biology of S100 proteins in some tissues such as brain and smooth muscle, little is known about S100 proteins in the normal mammalian reproductive tissue. In the present study, we investigated the distribution pattern of S100A6 (alternatively named calcyclin) in the murine ovary by immunohistochemical study using specific antibody. S100A6 was localized substantially in the cytoplasm of luteal cells, with concomitant expression of S100A11, another S100 protein, but not in the other type of cells such as oocytes, follicle epithelial cells (granulosa cells), and cells of stroma including theca interna cells in the murine ovary. S100A6-immunoreactive corpora lutea (CLs) were divided into two types: homogeneously and heterogeneously stained CLs, and possibly they may represent differentiating and mature CL, respectively. Our regression analysis revealed that expression level of S100A6 positively correlated with that of cytochrome P450 11A, a steroidogenic enzyme in the heterogeously stained CL. These results suggested that S100A6 may contribute to differentiation of steroidogenic activity of luteal cells in a synergistic manner with S100A11 by facilitating some shared functions

Robotic high-throughput purification of affinity-tagged recombinant proteins.

Science.gov (United States)

Wiesler, Simone C; Weinzierl, Robert O J

2015-01-01

Affinity purification of recombinant proteins has become the method of choice to obtain good quantities and qualities of proteins for a variety of downstream biochemical applications. While manual or FPLC-assisted purification techniques are generally time-consuming and labor-intensive, the advent of high-throughput technologies and liquid handling robotics has simplified and accelerated this process significantly. Additionally, without the human factor as a potential source of error, automated purification protocols allow for the generation of large numbers of proteins simultaneously and under directly comparable conditions. The delivered material is ideal for activity comparisons of different variants of the same protein. Here, we present our strategy for the simultaneous purification of up to 24 affinity-tagged proteins for activity measurements in biochemical assays. The protocol described is suitable for the scale typically required in individual research laboratories.

High-level transient expression of recombinant protein in lettuce.

Science.gov (United States)

Joh, Lawrence D; Wroblewski, Tadeusz; Ewing, Nicholas N; VanderGheynst, Jean S

2005-09-30

Transient expression following agroinfiltration of plant tissue was investigated as a system for producing recombinant protein. As a model system, Agrobacterium tumefaciens containing the beta-glucuronidase (GUS) gene was vacuum infiltrated into lettuce leaf disks. Infiltration with a suspension of 10(9) colony forming units/mL followed by incubation for 72 h at 22 degrees C in continuous darkness produced a maximum of 0.16% GUS protein based on dry tissue or 1.1% GUS protein based on total soluble protein. This compares favorably to expression levels for commercially manufactured GUS protein from transgenic corn seeds. A. tumefaciens culture medium pH between 5.6 and 7.0 and surfactant concentrations lettuce to produce GUS protein more rapidly, but final levels did not exceed the GUS production in leaves incubated in continuous darkness after 72 h at 22 degrees C. The kinetics of GUS expression during incubation in continuous light and dark were represented well using a logistic model, with rate constants of 0.30 and 0.29/h, respectively. To semi-quantitatively measure the GUS expression in large numbers of leaf disks, a photometric enhancement of the standard histochemical staining method was developed. A linear relationship with an R2 value of 0.90 was determined between log10 (% leaf darkness) versus log10 (GUS activity). Although variability in expression level was observed, agroinfiltration appears to be a promising technology that could potentially be scaled up to produce high-value recombinant proteins in planta. Copyright 2005 Wiley Periodicals, Inc

Cloning and expression of the recombinant NP24I protein from ...

African Journals Online (AJOL)

Jane

2011-10-24

Oct 24, 2011 ... protein from tomato fruit and study of its antimicrobial ... the recombinant NP24, as well as to prove the activity of native protein on the bacterial as well as fungal .... The antifungal effect of the recombinant NP24I protein was.

Gene Delivery into Plant Cells for Recombinant Protein Production

Directory of Open Access Journals (Sweden)

Qiang Chen

2015-01-01

Full Text Available Recombinant proteins are primarily produced from cultures of mammalian, insect, and bacteria cells. In recent years, the development of deconstructed virus-based vectors has allowed plants to become a viable platform for recombinant protein production, with advantages in versatility, speed, cost, scalability, and safety over the current production paradigms. In this paper, we review the recent progress in the methodology of agroinfiltration, a solution to overcome the challenge of transgene delivery into plant cells for large-scale manufacturing of recombinant proteins. General gene delivery methodologies in plants are first summarized, followed by extensive discussion on the application and scalability of each agroinfiltration method. New development of a spray-based agroinfiltration and its application on field-grown plants is highlighted. The discussion of agroinfiltration vectors focuses on their applications for producing complex and heteromultimeric proteins and is updated with the development of bridge vectors. Progress on agroinfiltration in Nicotiana and non-Nicotiana plant hosts is subsequently showcased in context of their applications for producing high-value human biologics and low-cost and high-volume industrial enzymes. These new advancements in agroinfiltration greatly enhance the robustness and scalability of transgene delivery in plants, facilitating the adoption of plant transient expression systems for manufacturing recombinant proteins with a broad range of applications.

Recombinant DNA production of spider silk proteins.

Science.gov (United States)

Tokareva, Olena; Michalczechen-Lacerda, Valquíria A; Rech, Elíbio L; Kaplan, David L

2013-11-01

Spider dragline silk is considered to be the toughest biopolymer on Earth due to an extraordinary combination of strength and elasticity. Moreover, silks are biocompatible and biodegradable protein-based materials. Recent advances in genetic engineering make it possible to produce recombinant silks in heterologous hosts, opening up opportunities for large-scale production of recombinant silks for various biomedical and material science applications. We review the current strategies to produce recombinant spider silks. © 2013 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

Yeast synthetic biology for the production of recombinant therapeutic proteins.

Science.gov (United States)

Kim, Hyunah; Yoo, Su Jin; Kang, Hyun Ah

2015-02-01

The production of recombinant therapeutic proteins is one of the fast-growing areas of molecular medicine and currently plays an important role in treatment of several diseases. Yeasts are unicellular eukaryotic microbial host cells that offer unique advantages in producing biopharmaceutical proteins. Yeasts are capable of robust growth on simple media, readily accommodate genetic modifications, and incorporate typical eukaryotic post-translational modifications. Saccharomyces cerevisiae is a traditional baker's yeast that has been used as a major host for the production of biopharmaceuticals; however, several nonconventional yeast species including Hansenula polymorpha, Pichia pastoris, and Yarrowia lipolytica have gained increasing attention as alternative hosts for the industrial production of recombinant proteins. In this review, we address the established and emerging genetic tools and host strains suitable for recombinant protein production in various yeast expression systems, particularly focusing on current efforts toward synthetic biology approaches in developing yeast cell factories for the production of therapeutic recombinant proteins. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permission@oup.com.

Genome engineering for improved recombinant protein expression in Escherichia coli.

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Mahalik, Shubhashree; Sharma, Ashish K; Mukherjee, Krishna J

2014-12-19

A metabolic engineering perspective which views recombinant protein expression as a multistep pathway allows us to move beyond vector design and identify the downstream rate limiting steps in expression. In E.coli these are typically at the translational level and the supply of precursors in the form of energy, amino acids and nucleotides. Further recombinant protein production triggers a global cellular stress response which feedback inhibits both growth and product formation. Countering this requires a system level analysis followed by a rational host cell engineering to sustain expression for longer time periods. Another strategy to increase protein yields could be to divert the metabolic flux away from biomass formation and towards recombinant protein production. This would require a growth stoppage mechanism which does not affect the metabolic activity of the cell or the transcriptional or translational efficiencies. Finally cells have to be designed for efficient export to prevent buildup of proteins inside the cytoplasm and also simplify downstream processing. The rational and the high throughput strategies that can be used for the construction of such improved host cell platforms for recombinant protein expression is the focus of this review.

Use of a Chimeric Hsp70 to Enhance the Quality of Recombinant Plasmodium falciparum S-Adenosylmethionine Decarboxylase Protein Produced in Escherichia coli

Science.gov (United States)

Makhoba, Xolani Henry; Burger, Adélle; Coertzen, Dina; Zininga, Tawanda; Birkholtz, Lyn-Marie; Shonhai, Addmore

2016-01-01

S-adenosylmethionine decarboxylase (PfAdoMetDC) from Plasmodium falciparum is a prospective antimalarial drug target. The production of recombinant PfAdoMetDC for biochemical validation as a drug target is important. The production of PfAdoMetDC in Escherichia coli has been reported to result in unsatisfactory yields and poor quality product. The co-expression of recombinant proteins with molecular chaperones has been proposed as one way to improve the production of the former in E. coli. E. coli heat shock proteins DnaK, GroEL-GroES and DnaJ have previously been used to enhance production of some recombinant proteins. However, the outcomes were inconsistent. An Hsp70 chimeric protein, KPf, which is made up of the ATPase domain of E. coli DnaK and the substrate binding domain of P. falciparum Hsp70 (PfHsp70) has been previously shown to exhibit chaperone function when it was expressed in E. coli cells whose resident Hsp70 (DnaK) function was impaired. We proposed that because of its domain constitution, KPf would most likely be recognised by E. coli Hsp70 co-chaperones. Furthermore, because it possesses a substrate binding domain of plasmodial origin, KPf would be primed to recognise recombinant PfAdoMetDC expressed in E. coli. First, using site-directed mutagenesis, followed by complementation assays, we established that KPf with a mutation in the hydrophobic residue located in its substrate binding cavity was functionally compromised. We further co-expressed PfAdoMetDC with KPf, PfHsp70 and DnaK in E. coli cells either in the absence or presence of over-expressed GroEL-GroES chaperonin. The folded and functional status of the produced PfAdoMetDC was assessed using limited proteolysis and enzyme assays. PfAdoMetDC co-expressed with KPf and PfHsp70 exhibited improved activity compared to protein co-expressed with over-expressed DnaK. Our findings suggest that chimeric KPf may be an ideal Hsp70 co-expression partner for the production of recombinant plasmodial

Extensive Lysine Methylation in Hyperthermophilic Crenarchaea: Potential Implications for Protein Stability and Recombinant Enzymes

Directory of Open Access Journals (Sweden)

Catherine H. Botting

2010-01-01

Full Text Available In eukarya and bacteria, lysine methylation is relatively rare and is catalysed by sequence-specific lysine methyltransferases that typically have only a single-protein target. Using RNA polymerase purified from the thermophilic crenarchaeum Sulfolobus solfataricus, we identified 21 methyllysines distributed across 9 subunits of the enzyme. The modified lysines were predominantly in α-helices and showed no conserved sequence context. A limited survey of the Thermoproteus tenax proteome revealed widespread modification with 52 methyllysines in 30 different proteins. These observations suggest the presence of an unusual lysine methyltransferase with relaxed specificity in the crenarchaea. Since lysine methylation is known to enhance protein thermostability, this may be an adaptation to a thermophilic lifestyle. The implications of this modification for studies and applications of recombinant crenarchaeal enzymes are discussed.

Selective Advantage of Recombination in Evolving Protein Populations:. a Lattice Model Study

Science.gov (United States)

Williams, Paul D.; Pollock, David D.; Goldstein, Richard A.

Recent research has attempted to clarify the contributions of several mutational processes, such as substitutions or homologous recombination. Simplistic, tractable protein models, which determine the compact native structure phenotype from the sequence genotype, are well-suited to such studies. In this paper, we use a lattice-protein model to examine the effects of point mutation and homologous recombination on evolving populations of proteins. We find that while the majority of mutation and recombination events are neutral or deleterious, recombination is far more likely to be beneficial. This results in a faster increase in fitness during evolution, although the final fitness level is not significantly changed. This transient advantage provides an evolutionary advantage to subpopulations that undergo recombination, allowing fixation of recombination to occur in the population.

Methods for Using Small Non-Coding RNAs to Improve Recombinant Protein Expression in Mammalian Cells

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Sarah Inwood

2018-01-01

Full Text Available The ability to produce recombinant proteins by utilizing different “cell factories” revolutionized the biotherapeutic and pharmaceutical industry. Chinese hamster ovary (CHO cells are the dominant industrial producer, especially for antibodies. Human embryonic kidney cells (HEK, while not being as widely used as CHO cells, are used where CHO cells are unable to meet the needs for expression, such as growth factors. Therefore, improving recombinant protein expression from mammalian cells is a priority, and continuing effort is being devoted to this topic. Non-coding RNAs are RNA segments that are not translated into a protein and often have a regulatory role. Since their discovery, major progress has been made towards understanding their functions. Non-coding RNA has been investigated extensively in relation to disease, especially cancer, and recently they have also been used as a method for engineering cells to improve their protein expression capability. In this review, we provide information about methods used to identify non-coding RNAs with the potential of improving recombinant protein expression in mammalian cell lines.

Polysome profiling of mAb producing CHO cell lines links translational control of cell proliferation and recombinant mRNA loading onto ribosomes with global and recombinant protein synthesis.

Science.gov (United States)

Godfrey, Charlotte L; Mead, Emma J; Daramola, Olalekan; Dunn, Sarah; Hatton, Diane; Field, Ray; Pettman, Gary; Smales, C Mark

2017-08-01

mRNA translation is a key process determining growth, proliferation and duration of a Chinese hamster ovary (CHO) cell culture and influences recombinant protein synthesis rate. During bioprocessing, CHO cells can experience stresses leading to reprogramming of translation and decreased global protein synthesis. Here we apply polysome profiling to determine reprogramming and translational capabilities in host and recombinant monoclonal antibody-producing (mAb) CHO cell lines during batch culture. Recombinant cell lines with the fastest cell specific growth rates were those with the highest global translational efficiency. However, total ribosomal capacity, determined from polysome profiles, did not relate to the fastest growing or highest producing mAb cell line, suggesting it is the ability to utilise available machinery that determines protein synthetic capacity. Cell lines with higher cell specific productivities tended to have elevated recombinant heavy chain transcript copy numbers, localised to the translationally active heavy polysomes. The highest titre cell line was that which sustained recombinant protein synthesis and maintained high recombinant transcript copy numbers in polysomes. Investigation of specific endogenous transcripts revealed a number that maintained or reprogrammed into heavy polysomes, identifying targets for potential cell engineering or those with 5' untranslated regions that might be utilised to enhance recombinant transcript translation. © 2017 The Authors. Biotechnology Journal published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Overexpression of the S100A2 protein as a prognostic marker for patients with stage II and III colorectal cancer

Science.gov (United States)

MASUDA, TAIKI; ISHIKAWA, TOSHIAKI; MOGUSHI, KAORU; OKAZAKI, SATOSHI; ISHIGURO, MEGUMI; IIDA, SATORU; MIZUSHIMA, HIROSHI; TANAKA, HIROSHI; UETAKE, HIROYUKI; SUGIHARA, KENICHI

2016-01-01

We aimed to identify a novel prognostic biomarker related to recurrence in stage II and III colorectal cancer (CRC) patients. Stage II and III CRC tissue mRNA expression was profiled using an Affymetrix Gene Chip, and copy number profiles of 125 patients were generated using an Affymetrix 250K Sty array. Genes showing both upregulated expression and copy number gains in cases involving recurrence were extracted as candidate biomarkers. The protein expression of the candidate gene was assessed using immunohistochemical staining of tissue from 161 patients. The relationship between protein expression and clinicopathological features was also examined. We identified 9 candidate genes related to recurrence of stage II and III CRC, whose mRNA expression was significantly higher in CRC than in normal tissue. Of these proteins, the S100 calcium-binding protein A2 (S100A2) has been observed in several human cancers. S100A2 protein overexpression in CRC cells was associated with significantly worse overall survival and relapse-free survival, indicating that S100A2 is an independent risk factor for stage II and III CRC recurrence. S100A2 overexpression in cancer cells could be a biomarker of poor prognosis in stage II and III CRC recurrence and a target for treatment of this disease. PMID:26783118

N-Glycosylation of Plant-produced Recombinant Proteins

NARCIS (Netherlands)

Bosch, H.J.; Castilho, A.; Loos, A.; Schots, A.; Steinkeller, H.

2013-01-01

Plants are gaining increasingly acceptance as a production platform for recombinant proteins. One reason for this is their ability to carry out posttranslational protein modifications in a similar if not identical way as mammalian cells. The capability of plants to carry out human-like complex

Application of native signal sequences for recombinant proteins secretion in Pichia pastoris

DEFF Research Database (Denmark)

Borodina, Irina; Do, Duy Duc; Eriksen, Jens C.

Background Methylotrophic yeast Pichia pastoris is widely used for recombinant protein production, largely due to its ability to secrete correctly folded heterologous proteins to the fermentation medium. Secretion is usually achieved by cloning the recombinant gene after a leader sequence, where...... alpha‐mating factor (MF) prepropeptide from Saccharomyces cerevisiae is most commonly used. Our aim was to test whether signal peptides from P. pastoris native secreted proteins could be used to direct secretion of recombinant proteins. Results Eleven native signal peptides from P. pastoris were tested...... by optimization of expression of three different proteins in P. pastoris. Conclusions Native signal peptides from P. pastoris can be used to direct secretion of recombinant proteins. A novel USER‐based P. pastoris system allows easy cloning of protein‐coding gene with the promoter and leader sequence of choice....

Protective efficacy of six immunogenic recombinant proteins of Vibrio anguillarum and evaluation them as vaccine candidate for flounder (Paralichthys olivaceus).

Science.gov (United States)

Xing, Jing; Xu, Hongsen; Wang, Yang; Tang, Xiaoqian; Sheng, Xiuzhen; Zhan, Wenbin

2017-06-01

Vibrio anguillarum is a severe bacterium that causes terminal haemorrhagic septicaemia in freshwater and marine fish. Virulence-associated proteins play an important role in bacterial pathogenicity and could be applied for immunoprophylaxis. In this study, six antigenic proteins from V. anguillarum were selected and the immune protective efficacy of their recombinant proteins was investigated. VirA, CheR, FlaC, OmpK, OmpR and Hsp33 were recombinantly produced and the reactions of recombinant proteins to flounder-anti-V. anguillarum antibodies (fV-ab) were detected, respectively. Then the recombinant proteins were injected to fish, after immunization, the percentages of surface membrane immunoglobulin-positive (sIg+) cell in lymphocytes, total antibodies, antibodies against V. anguillarum, antibodies against recombinant proteins and relative percent survival (RPS) were analyzed, respectively. The results showed that all the recombinant proteins could react to fV-ab, proliferate sIg + cells in lymphocytes and induce production of total antibodies, specific antibodies against V. anguillarum or the recombinant proteins; the RPS of rVirA, rCheR, rFlaC, rOmpK, rOmpR and rHsp33 against V. anguillarum was 70.27%, 27.03%, 16.22%, 62.16%, 45.95% and 81.08%, respectively. The results revealed that rHsp33, rVirA and rOmpK have good protections against V. anguillarum and could be vaccine candidates against V. anguillarum. Copyright © 2017 Elsevier Ltd. All rights reserved.

Case report: Extreme levels of serum S-100B in a patient with chronic subdural hematoma

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Malin Elisabet Persson

2012-12-01

Full Text Available The protein S-100B is a biomarker increasingly used within neurosurgery and neurointensive care. As a relatively sensitive, yet unspecific, indicator of CNS pathology, potential sources of error must be clearly understood when interpreting serum S-100B levels. This case report studied the course of a 46-year-old gentleman with a chronic subdural haemorrhage, serum S-100B levels of 22 μg/L and a history of malignant melanoma. Both intra- and extra-cranial sources of S-100B are evaluated and imply an unclear contribution of several sources to the total serum concentration. Potential sources of error when interpreting serum concentrations of S-100B are discussed

Fast and easy protocol for the purification of recombinant S-layer protein for synthetic biology applications

KAUST Repository

Norville, Julie E.

2011-06-17

A goal of synthetic biology is to make biological systems easier to engineer. One of the aims is to design, with nanometer-scale precision, biomaterials with well-defined properties. The surface-layer protein SbpA forms 2D arrays naturally on the cell surface of Lysinibacillus sphaericus, but also as the purified protein in solution upon the addition of divalent cations. The high propensity of SbpA to form crystalline arrays, which can be simply controlled by divalent cations, and the possibility to genetically alter the protein, make SbpA an attractive molecule for synthetic biology. To be a useful tool, however, it is important that a simple protocol can be used to produce recombinant wild-type and modified SbpA in large quantities and in a biologically active form. The present study addresses this requirement by introducing a mild and non-denaturing purification protocol to produce milligram quantities of recombinant, active SbpA.

ACCUMULATION OF RECOMBINANT FUSION PROTEIN – SECRETORY ANALOG OF Ag85B AND ESAT6 MYCOBACTERIUM TUBERCULOSIS PROTEINS – IN TRANSGENIC Lemna minor L. PLANTS

Directory of Open Access Journals (Sweden)

A.A.Peterson

2015-10-01

Full Text Available Determination of the presence of the recombinant fusion protein (ESAT6-Ag85B(ΔTMD-6His and its accumulation level in duckweed plants (Lemna minor L. was the aim of the research. ESAT6 and Ag85B are secretory proteins of Mycobacterium tuberculosis and are considered as potential candidates for development of new vaccine against tuberculosis (TB. Transgenic duckweed plants were obtained previously by Agrobacterium rhizogenes-mediated transformation and possessed fusion gene sequence esxA-fbpBΔTMD. Specific polyclonal antibodies were produced in immunized mice to identify levels of accumulation of TB antigens in plants. Recombinant antigen used for mice immunization was obtained in our laboratory by expression in E. coli. Western blot analysis revealed the recombinant tuberculosis antigen ESAT6-Ag85B(ΔTMD-6His in extracts from transgenic L. minor plants. The level of accumulation of the protein corresponds to 0.4-0.5 µg protein per 1 g of fresh weight of plant. Additionally, the accumulation of recombinant protein was investigated in lyophilized transgenic plants after 1.5 year storage. Duckweed plants accumulating a recombinant analogue of M. tuberculosis secretory proteins can be used for development of plant-based edible vaccines.

Detection of Antibodies to U.S. Isolates of Avian Pneumovirus by a Recombinant Nucleocapsid Protein-Based Sandwich Enzyme-Linked Immunosorbent Assay

OpenAIRE

Gulati, Baldev R.; Munir, Shirin; Patnayak, Devi P.; Goyal, Sagar M.; Kapur, Vivek

2001-01-01

The nucleocapsid (N) protein of subgroup C (United States-specific) avian pneumovirus (APV/US) was expressed in Escherichia coli, and antibodies to the recombinant N protein were shown to specifically recognize the ≈47-kDa N protein of APV/US by Western immunoblot analysis. The recombinant APV/US N protein was used in a sandwich-capture enzyme-linked immunosorbent assay (ELISA), and the resulting assay was found to be more sensitive and specific than the routine indirect ELISA for the detecti...

Targeting S100P Inhibits Colon Cancer Growth and Metastasis by Lentivirus-Mediated RNA Interference and Proteomic Analysis

Science.gov (United States)

Jiang, Lei; Lai, Yiu-Kay; Zhang, Jinfang; Wang, Hua; Lin, Marie CM; He, Ming-liang; Kung, Hsiang-fu

2011-01-01

S100P was recently found to be overexpressed in a variety of cancers and is considered a potential target for cancer therapy, but the functional role or mechanism of action of S100P in colon cancer is not fully understood. In the present study, we knocked down the gene expression of S100P in colon cancer cells using lentivirus-mediated RNA interference. This step resulted in significant inhibition of cancer cell growth, migration and invasion in vitro and tumor growth and liver metastasis in vivo. Moreover, S100P downstream target proteins were identified by proteomic analysis in colon cancer DLD-1 cells with deletion of S100P. Knockdown of S100P led to downregulation of thioredoxin 1 and β-tubulin and upregulation of Rho guanosine diphosphate (GDP) dissociation inhibitor α (RhoGDIA), all potential therapeutic targets in cancer. Taken together, these findings suggest that S100P plays an important role in colon tumorigenesis and metastasis, and the comprehensive and comparative analyses of proteins associated with S100P could contribute to understanding the downstream signal cascade of S100P, leading to tumorigenesis and metastasis. PMID:21327297

Purification and partial characterization of canine S100A12.

Science.gov (United States)

Heilmann, Romy M; Suchodolski, Jan S; Steiner, Jörg M

2010-12-01

Canine S100A12 (cS100A12) is a calcium-binding protein of the S100 superfamily of EF-hand proteins, and its expression is restricted to neutrophils and monocytes. Interaction of S100A12 with the receptor for advanced glycation end products (RAGE) has been suggested to play a central role in inflammation. Moreover, S100A12 has been shown to represent a sensitive and specific marker for gastrointestinal inflammation in humans. Only human, porcine, bovine, and rabbit S100A12 have been purified to date, and an immunoassay for the quantification of S100A12 is available only for humans. Therefore, the aim of this study was to develop a protocol for the purification of S100A12 and to partially characterize this protein in the dog (Canis lupus familiaris) as a prelude to the development of an immunologic method for its detection and quantification in canine serum and fecal specimens. Leukocytes were isolated from canine whole blood by dextran sedimentation, and canine S100A12 was extracted from the cytosol fraction of these cells. Further purification of cS100A12 comprised of ammonium sulfate precipitation, hydrophobic interaction chromatography, and strong cation- and anion-exchange column chromatography. Canine S100A12 was successfully purified from canine whole blood. The relative molecular mass of the protein was estimated at 10,379.5 and isoelectric focusing revealed an isoelectric point of 6.0. The approximate specific absorbance of cS100A12 at 280 nm was determined to be 1.78 for a 1 mg/ml solution. The N-terminal AA sequence of the first 15 residues of cS100A12 was Thr-Lys-Leu-Glu-Asp-His-X-Glu-Gly-Ile-Val-Asp-Val-Phe-His, and revealed 100% identity with the predicted protein sequence available through the canine genome project. Sequence homology for the 14 N-terminal residues identified for cS100A12 with those of feline, bovine, porcine, and human S100A12 was 78.6%. We conclude that canine S100A12 can be successfully purified from canine whole blood using the

Escherichia coli fusion carrier proteins act as solubilizing agents for recombinant uncoupling protein 1 through interactions with GroEL

International Nuclear Information System (INIS)

Douette, Pierre; Navet, Rachel; Gerkens, Pascal; Galleni, Moreno; Levy, Daniel; Sluse, Francis E.

2005-01-01

Fusing recombinant proteins to highly soluble partners is frequently used to prevent aggregation of recombinant proteins in Escherichia coli. Moreover, co-overexpression of prokaryotic chaperones can increase the amount of properly folded recombinant proteins. To understand the solubility enhancement of fusion proteins, we designed two recombinant proteins composed of uncoupling protein 1 (UCP1), a mitochondrial membrane protein, in fusion with MBP or NusA. We were able to express soluble forms of MBP-UCP1 and NusA-UCP1 despite the high hydrophobicity of UCP1. Furthermore, the yield of soluble fusion proteins depended on co-overexpression of GroEL that catalyzes folding of polypeptides. MBP-UCP1 was expressed in the form of a non-covalent complex with GroEL. MBP-UCP1/GroEL was purified and characterized by dynamic light scattering, gel filtration, and electron microscopy. Our findings suggest that MBP and NusA act as solubilizing agents by forcing the recombinant protein to pass through the bacterial chaperone pathway in the context of fusion protein

Hornerin, an S100 family protein, is functional in breast cells and aberrantly expressed in breast cancer

International Nuclear Information System (INIS)

Fleming, Jodie M; Ginsburg, Erika; Oliver, Shannon D; Goldsmith, Paul; Vonderhaar, Barbara K

2012-01-01

Recent evidence suggests an emerging role for S100 protein in breast cancer and tumor progression. These ubiquitous proteins are involved in numerous normal and pathological cell functions including inflammatory and immune responses, Ca 2+ homeostasis, the dynamics of cytoskeleton constituents, as well as cell proliferation, differentiation, and death. Our previous proteomic analysis demonstrated the presence of hornerin, an S100 family member, in breast tissue and extracellular matrix. Hornerin has been reported in healthy skin as well as psoriatic and regenerating skin after wound healing, suggesting a role in inflammatory/immune response or proliferation. In the present study we investigated hornerin’s potential role in normal breast cells and breast cancer. The expression levels and localization of hornerin in human breast tissue, breast tumor biopsies, primary breast cells and breast cancer cell lines, as well as murine mammary tissue were measured via immunohistochemistry, western blot analysis and PCR. Antibodies were developed against the N- and C-terminus of the protein for detection of proteolytic fragments and their specific subcellular localization via fluorescent immunocytochemisty. Lastly, cells were treated with H 2 O 2 to detect changes in hornerin expression during induction of apoptosis/necrosis. Breast epithelial cells and stromal fibroblasts and macrophages express hornerin and show unique regulation of expression during distinct phases of mammary development. Furthermore, hornerin expression is decreased in invasive ductal carcinomas compared to invasive lobular carcinomas and less aggressive breast carcinoma phenotypes, and cellular expression of hornerin is altered during induction of apoptosis. Finally, we demonstrate the presence of post-translational fragments that display differential subcellular localization. Our data opens new possibilities for hornerin and its proteolytic fragments in the control of mammary cell function and breast

Hornerin, an S100 family protein, is functional in breast cells and aberrantly expressed in breast cancer

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Fleming Jodie M

2012-06-01

Full Text Available Abstract Background Recent evidence suggests an emerging role for S100 protein in breast cancer and tumor progression. These ubiquitous proteins are involved in numerous normal and pathological cell functions including inflammatory and immune responses, Ca2+ homeostasis, the dynamics of cytoskeleton constituents, as well as cell proliferation, differentiation, and death. Our previous proteomic analysis demonstrated the presence of hornerin, an S100 family member, in breast tissue and extracellular matrix. Hornerin has been reported in healthy skin as well as psoriatic and regenerating skin after wound healing, suggesting a role in inflammatory/immune response or proliferation. In the present study we investigated hornerin’s potential role in normal breast cells and breast cancer. Methods The expression levels and localization of hornerin in human breast tissue, breast tumor biopsies, primary breast cells and breast cancer cell lines, as well as murine mammary tissue were measured via immunohistochemistry, western blot analysis and PCR. Antibodies were developed against the N- and C-terminus of the protein for detection of proteolytic fragments and their specific subcellular localization via fluorescent immunocytochemisty. Lastly, cells were treated with H2O2 to detect changes in hornerin expression during induction of apoptosis/necrosis. Results Breast epithelial cells and stromal fibroblasts and macrophages express hornerin and show unique regulation of expression during distinct phases of mammary development. Furthermore, hornerin expression is decreased in invasive ductal carcinomas compared to invasive lobular carcinomas and less aggressive breast carcinoma phenotypes, and cellular expression of hornerin is altered during induction of apoptosis. Finally, we demonstrate the presence of post-translational fragments that display differential subcellular localization. Conclusions Our data opens new possibilities for hornerin and its

Nonreplicative RNA Recombination of an Animal Plus-Strand RNA Virus in the Absence of Efficient Translation of Viral Proteins.

Science.gov (United States)

Kleine Büning, Maximiliane; Meyer, Denise; Austermann-Busch, Sophia; Roman-Sosa, Gleyder; Rümenapf, Tillmann; Becher, Paul

2017-04-01

RNA recombination is a major driving force for the evolution of RNA viruses and is significantly implicated in the adaptation of viruses to new hosts, changes of virulence, as well as in the emergence of new viruses including drug-resistant and escape mutants. However, the molecular details of recombination in animal RNA viruses are only poorly understood. In order to determine whether viral RNA recombination depends on translation of viral proteins, a nonreplicative recombination system was established which is based on cotransfection of cells with synthetic bovine viral diarrhea virus (family Flaviviridae) RNA genome fragments either lacking the internal ribosome entry site required for cap-independent translation or lacking almost the complete polyprotein coding region. The emergence of a number of recombinant viruses demonstrated that IRES-mediated translation of viral proteins is dispensable for efficient recombination and suggests that RNA recombination can occur in the absence of viral proteins. Analyses of 58 independently emerged viruses led to the detection of recombinant genomes with duplications, deletions and insertions in the 5' terminal region of the open reading frame, leading to enlarged core fusion proteins detectable by Western blot analysis. This demonstrates a remarkable flexibility of the pestivirus core protein. Further experiments with capped and uncapped genome fragments containing a luciferase gene for monitoring the level of protein translation revealed that even a ∼1,000-fold enhancement of translation of viral proteins did not increase the frequency of RNA recombination. Taken together, this study highlights that nonreplicative RNA recombination does not require translation of viral proteins. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Soluble expression of recombinant proteins in the cytoplasm of Escherichia coli

DEFF Research Database (Denmark)

Sørensen, Hans; Mortensen, Kim

2005-01-01

Pure, soluble and functional proteins are of high demand in modern biotechnology. Natural protein sources rarely meet the requirements for quantity, ease of isolation or price and hence recombinant technology is often the method of choice. Recombinant cell factories are constantly employed...... molecular tools available. In spite of all these qualities, expression of recombinant proteins with E. coli as the host often results in insoluble and/or nonfunctional proteins. Here we review new approaches to overcome these obstacles by strategies that focus on either controlled expression of target...... for the production of protein preparations bound for downstream purification and processing. Eschericia coli is a frequently used host, since it facilitates protein expression by its relative simplicity, its inexpensive and fast high density cultivation, the well known genetics and the large number of compatible...

Polyclonal Antibodies to a Recombinant Coat Protein of Potato Virus A

Czech Academy of Sciences Publication Activity Database

Čeřovská, Noemi; Moravec, Tomáš; Velemínský, Jiří

2002-01-01

Roč. 46, - (2002), s. 147-151 ISSN 0001-723X R&D Projects: GA ČR GA310/00/0381 Institutional research plan: CEZ:AV0Z5038910 Keywords : Potato virus A * recombinant coat protein * Escherichia coli Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.660, year: 2002

Fusion protein-based biofilm fabrication composed of recombinant azurin–myoglobin for dual-level biomemory application

Energy Technology Data Exchange (ETDEWEB)

Lee, Taek [Research Institute for Basic Science, Sogang University, Heukseok-dong, Dongjak-gu, Seoul 156-756 (Korea, Republic of); Chung, Yong-Ho; Yoon, Jinho [Department of Chemical and Biomolecular Engineering, Sogang University, Heukseok-dong, Dongjak-gu, 35 Baekbeom-ro (Sinsu-dong), Mapo-gu, Seoul 121-742 (Korea, Republic of); Min, Junhong [School of Integrative Engineering, Chung-Ang University, Heukseok-dong, Dongjak-gu, Seoul 156-756 (Korea, Republic of); Choi, Jeong-Woo, E-mail: jwchoi@sogang.ac.kr [Department of Chemical and Biomolecular Engineering, Sogang University, Heukseok-dong, Dongjak-gu, 35 Baekbeom-ro (Sinsu-dong), Mapo-gu, Seoul 121-742 (Korea, Republic of)

2014-11-30

Graphical abstract: - Highlights: • We developed the fusion protein-based biofilm on the inorganic surface. • For making the fusion protein, the recombinant azurin and the myoglobin was conjugated by the native chemical ligation method. • The developed fusion protein shows unique electrochemical property. • The proposed fusion protein biofilm appears to be a good method for dual-level biomemory device. - Abstract: In the present study, a fusion protein-based biofilm composed of a recombinant azurin–myoglobin (Azu-Myo) has been developed and confirmed its original electrochemical property for dual-level biomemory device application. For this purpose, the azurin was modified with cysteine residues for direct immobilization and conjugation. Then, the recombinant azurin was conjugated with the myoglobin via a sulfo-SMCC bifunctional linker using the chemical ligation method (CLM). The SDS-PAGE and UV–vis spectroscopy were performed to examine the fusion protein conjugates. The prepared Azu-Myo fusion protein was self-assembled onto Au substrate for the biofilm fabrication. Then, the atomic force microscopy (AFM) was used to confirm the immobilization and the surface-enhanced Raman spectroscopy (SERS) was carried out to the surface analysis. Also, the cyclic voltammetry (CV) was carried out to observe an electrochemical property of fabricated biofilm. As a result, the two pair of redox potential values was obtained for dual-level biomemory device application. Then, the dual-level biomemory function was verified by the multi-potential chronoamperometry (MPCA). The results indicate a new fabrication method and material combination for advances in bioelectronic device development.

Fusion protein-based biofilm fabrication composed of recombinant azurin–myoglobin for dual-level biomemory application

International Nuclear Information System (INIS)

Lee, Taek; Chung, Yong-Ho; Yoon, Jinho; Min, Junhong; Choi, Jeong-Woo

2014-01-01

Graphical abstract: - Highlights: • We developed the fusion protein-based biofilm on the inorganic surface. • For making the fusion protein, the recombinant azurin and the myoglobin was conjugated by the native chemical ligation method. • The developed fusion protein shows unique electrochemical property. • The proposed fusion protein biofilm appears to be a good method for dual-level biomemory device. - Abstract: In the present study, a fusion protein-based biofilm composed of a recombinant azurin–myoglobin (Azu-Myo) has been developed and confirmed its original electrochemical property for dual-level biomemory device application. For this purpose, the azurin was modified with cysteine residues for direct immobilization and conjugation. Then, the recombinant azurin was conjugated with the myoglobin via a sulfo-SMCC bifunctional linker using the chemical ligation method (CLM). The SDS-PAGE and UV–vis spectroscopy were performed to examine the fusion protein conjugates. The prepared Azu-Myo fusion protein was self-assembled onto Au substrate for the biofilm fabrication. Then, the atomic force microscopy (AFM) was used to confirm the immobilization and the surface-enhanced Raman spectroscopy (SERS) was carried out to the surface analysis. Also, the cyclic voltammetry (CV) was carried out to observe an electrochemical property of fabricated biofilm. As a result, the two pair of redox potential values was obtained for dual-level biomemory device application. Then, the dual-level biomemory function was verified by the multi-potential chronoamperometry (MPCA). The results indicate a new fabrication method and material combination for advances in bioelectronic device development

Inflammation and pancreatic cancer: molecular and functional interactions between S100A8, S100A9, NT-S100A8 and TGFβ1.

Science.gov (United States)

Basso, Daniela; Bozzato, Dania; Padoan, Andrea; Moz, Stefania; Zambon, Carlo-Federico; Fogar, Paola; Greco, Eliana; Scorzeto, Michele; Simonato, Francesca; Navaglia, Filippo; Fassan, Matteo; Pelloso, Michela; Dupont, Sirio; Pedrazzoli, Sergio; Fassina, Ambrogio; Plebani, Mario

2014-03-26

In order to gain further insight on the crosstalk between pancreatic cancer (PDAC) and stromal cells, we investigated interactions occurring between TGFβ1 and the inflammatory proteins S100A8, S100A9 and NT-S100A8, a PDAC-associated S100A8 derived peptide, in cell signaling, intracellular calcium (Cai2+) and epithelial to mesenchymal transition (EMT). NF-κB, Akt and mTOR pathways, Cai2+ and EMT were studied in well (Capan1 and BxPC3) and poorly differentiated (Panc1 and MiaPaCa2) cell lines. NT-S100A8, one of the low molecular weight N-terminal peptides from S100A8 to be released by PDAC-derived proteases, shared many effects on NF-κB, Akt and mTOR signaling with S100A8, but mainly with TGFβ1. The chief effects of S100A8, S100A9 and NT-S100A8 were to inhibit NF-κB and stimulate mTOR; the molecules inhibited Akt in Smad4-expressing, while stimulated Akt in Smad4 negative cells. By restoring Smad4 expression in BxPC3 and silencing it in MiaPaCa2, S100A8 and NT-S100A8 were shown to inhibit NF-κB and Akt in the presence of an intact TGFβ1 canonical signaling pathway. TGFβ1 counteracted S100A8, S100A9 and NT-S100A8 effects in Smad4 expressing, not in Smad4 negative cells, while it synergized with NT-S100A8 in altering Cai2+ and stimulating PDAC cell growth. The effects of TGFβ1 on both EMT (increased Twist and decreased N-Cadherin expression) and Cai2+ were antagonized by S100A9, which formed heterodimers with TGFβ1 (MALDI-TOF/MS and co-immuno-precipitation). The effects of S100A8 and S100A9 on PDAC cell signaling appear to be cell-type and context dependent. NT-S100A8 mimics the effects of TGFβ1 on cell signaling, and the formation of complexes between TGFβ1 with S100A9 appears to be the molecular mechanism underlying the reciprocal antagonism of these molecules on cell signaling, Cai2+ and EMT.

Participation of the oviductal s100 calcium binding protein G in the genomic effect of estradiol that accelerates oviductal embryo transport in mated rats

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Croxatto Horacio B

2011-05-01

Full Text Available Abstract Background Mating changes the mechanism by which E2 regulates oviductal egg transport, from a non-genomic to a genomic mode. Previously, we found that E2 increased the expression of several genes in the oviduct of mated rats, but not in unmated rats. Among the transcripts that increased its level by E2 only in mated rats was the one coding for an s100 calcium binding protein G (s100 g whose functional role in the oviduct is unknown. Methods Herein, we investigated the participation of s100 g on the E2 genomic effect that accelerates oviductal transport in mated rats. Thus, we determined the effect of E2 on the mRNA and protein level of s100 g in the oviduct of mated and unmated rats. Then, we explored the effect of E2 on egg transport in unmated and mated rats under conditions in which s100 g protein was knockdown in the oviduct by a morpholino oligonucleotide against s100 g (s100 g-MO. In addition, the localization of s100 g in the oviduct of mated and unmated rats following treatment with E2 was also examined. Results Expression of s100 g mRNA progressively increased at 3-24 h after E2 treatment in the oviduct of mated rats while in unmated rats s100 g increased only at 12 and 24 hours. Oviductal s100 g protein increased 6 h following E2 and continued elevated at 12 and 24 h in mated rats, whereas in unmated rats s100 g protein increased at the same time points as its transcript. Administration of a morpholino oligonucleotide against s100 g transcript blocked the effect of E2 on egg transport in mated, but not in unmated rats. Finally, immunoreactivity of s100 g was observed only in epithelial cells of the oviducts of mated and unmated rats and it was unchanged after E2 treatment. Conclusions Mating affects the kinetic of E2-induced expression of s100 g although it not changed the cellular localization of s100 g in the oviduct after E2 . On the other hand, s100 g is a functional component of E2 genomic effect that accelerates egg

Divergence, recombination and retention of functionality during protein evolution

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Xu Yanlong O

2005-09-01

Full Text Available Abstract We have only a vague idea of precisely how protein sequences evolve in the context of protein structure and function. This is primarily because structural and functional contexts are not easily predictable from the primary sequence, and evaluating patterns of evolution at individual residue positions is also difficult. As a result of increasing biodiversity in genomics studies, progress is being made in detecting context-dependent variation in substitution processes, but it remains unclear exactly what context-dependent patterns we should be looking for. To address this, we have been simulating protein evolution in the context of structure and function using lattice models of proteins and ligands (or substrates. These simulations include thermodynamic features of protein stability and population dynamics. We refer to this approach as 'ab initio evolution' to emphasise the fact that the equilibrium details of fitness distributions arise from the physical principles of the system and not from any preconceived notions or arbitrary mathematical distributions. Here, we present results on the retention of functionality in homologous recombinants following population divergence. A central result is that protein structure characteristics can strongly influence recombinant functionality. Exceptional structures with many sequence options evolve quickly and tend to retain functionality -- even in highly diverged recombinants. By contrast, the more common structures with fewer sequence options evolve more slowly, but the fitness of recombinants drops off rapidly as homologous proteins diverge. These results have implications for understanding viral evolution, speciation and directed evolutionary experiments. Our analysis of the divergence process can also guide improved methods for accurately approximating folding probabilities in more complex but realistic systems.

A systematic investigation of production of synthetic prions from recombinant prion protein.

Science.gov (United States)

Schmidt, Christian; Fizet, Jeremie; Properzi, Francesca; Batchelor, Mark; Sandberg, Malin K; Edgeworth, Julie A; Afran, Louise; Ho, Sammy; Badhan, Anjna; Klier, Steffi; Linehan, Jacqueline M; Brandner, Sebastian; Hosszu, Laszlo L P; Tattum, M Howard; Jat, Parmjit; Clarke, Anthony R; Klöhn, Peter C; Wadsworth, Jonathan D F; Jackson, Graham S; Collinge, John

2015-12-01

According to the protein-only hypothesis, infectious mammalian prions, which exist as distinct strains with discrete biological properties, consist of multichain assemblies of misfolded cellular prion protein (PrP). A critical test would be to produce prion strains synthetically from defined components. Crucially, high-titre 'synthetic' prions could then be used to determine the structural basis of infectivity and strain diversity at the atomic level. While there have been multiple reports of production of prions from bacterially expressed recombinant PrP using various methods, systematic production of high-titre material in a form suitable for structural analysis remains a key goal. Here, we report a novel high-throughput strategy for exploring a matrix of conditions, additives and potential cofactors that might generate high-titre prions from recombinant mouse PrP, with screening for infectivity using a sensitive automated cell-based bioassay. Overall, approximately 20,000 unique conditions were examined. While some resulted in apparently infected cell cultures, this was transient and not reproducible. We also adapted published methods that reported production of synthetic prions from recombinant hamster PrP, but again did not find evidence of significant infectious titre when using recombinant mouse PrP as substrate. Collectively, our findings are consistent with the formation of prion infectivity from recombinant mouse PrP being a rare stochastic event and we conclude that systematic generation of prions from recombinant PrP may only become possible once the detailed structure of authentic ex vivo prions is solved. © 2015 The Authors.

Isolation of recombinant antibodies directed against surface proteins of Clostridium difficile.

Science.gov (United States)

Shirvan, Ali Nazari; Aitken, Robert

2016-01-01

Clostridium difficile has emerged as an increasingly important nosocomial pathogen and the prime causative agent of antibiotic-associated diarrhoea and pseudomembranous colitis in humans. In addition to toxins A and B, immunological studies using antisera from patients infected with C. difficile have shown that a number of other bacterial factors contribute to the pathogenesis, including surface proteins, which are responsible for adhesion, motility and other interactions with the human host. In this study, various clostridial targets, including FliC, FliD and cell wall protein 66, were expressed and purified. Phage antibody display yielded a large panel of specific recombinant antibodies, which were expressed, purified and characterised. Reactions of the recombinant antibodies with their targets were detected by enzyme-linked immunosorbent assay; and Western blotting suggested that linear rather than conformational epitopes were recognised. Binding of the recombinant antibodies to surface-layer proteins and their components showed strain specificity, with good recognition of proteins from C. difficile 630. However, no reaction was observed for strain R20291-a representative of the 027 ribotype. Binding of the recombinant antibodies to C. difficile M120 extracts indicated that a component of a surface-layer protein of this strain might possess immunoglobulin-binding activities. The recombinant antibodies against FliC and FliD proteins were able to inhibit bacterial motility. Copyright © 2016. Published by Elsevier Editora Ltda.

Heterologous expression of a truncated form of human recombinant vascular endothelial growth factor-A and its biological activity in wound healing

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Mohsen Khaki

2017-07-01

Full Text Available Objective(s: Vascular endothelial growth factor (VEGF is one of the most effective proteins in angiogenesis, mesenchymal stem cells (MSCs differentiation and wound healing. These abilities are therapeutic potential of VEGF in diabetic retinopathy, nephropathy and other tissue damage circumstances. In this study, recombinant VEGF was produced in Escherichia coli (E. coli system and then biological activity of this protein was evaluated in animal wound healing. Materials and Methods: E. coli BL21 (DE3 competent cells were transformed with pET32a-VEGF clone and induced by isopropyl-β-D-thio-galactoside (IPTG. The recombinant protein was purified byaffinity chromatography. Recombinant VEGF-A-based ointment (VEGF/Vaseline 0.8 mg/100 w/w was used for external wound (25×15mm thickness healing in animal model. In vivo activity of ointment was evaluated by clinical evidences and cytological microscopic assessment. Results: The recombinant protein with molecular weight of 45 kilodaltons (kDa and concentration of 0.8 mg/ml was produced.Immunoblotting data showed that the antigenic region of VEGF can be expressed in E. coli and the recombinant protein has similar epitopes with close antigenic properties to the natural form. Macroscopic findings and microscopic data showed that the recombinant VEGF-A ointment was effective on excisional wound healing. Conclusion: Recombinant VEGF-A produced by pET32a in E. coli, possesses acceptable structure and has wound healing capability.

Recominant Pinoresino-Lariciresinol Reductase, Recombinant Dirigent Protein And Methods Of Use

Science.gov (United States)

Lewis, Norman G.; Davin, Laurence B.; Dinkova-Kostova, Albena T.; Fujita, Masayuki , Gang; David R. , Sarkanen; Simo , Ford; Joshua D.

2003-10-21

Dirigent proteins and pinoresinol/lariciresinol reductases have been isolated, together with cDNAs encoding dirigent proteins and pinoresinol/lariciresinol reductases. Accordingly, isolated DNA sequences are provided from source species Forsythia intermedia, Thuja plicata, Tsuga heterophylla, Eucommia ulmoides, Linum usitatissimum, and Schisandra chinensis, which code for the expression of dirigent proteins and pinoresinol/lariciresinol reductases. In other aspects, replicable recombinant cloning vehicles are provided which code for dirigent proteins or pinoresinol/lariciresinol reductases or for a base sequence sufficiently complementary to at least a portion of dirigent protein or pinoresinol/lariciresinol reductase DNA or RNA to enable hybridization therewith. In yet other aspects, modified host cells are provided that have been transformed, transfected, infected and/or injected with a recombinant cloning vehicle and/or DNA sequence encoding dirigent protein or pinoresinol/lariciresinol reductase. Thus, systems and methods are provided for the recombinant expression of dirigent proteins and/or pinoresinol/lariciresinol reductases.

Regulation of homologous recombination repair protein Rad51 by Ku70

International Nuclear Information System (INIS)

Du Liqing; Liu Qiang; Wang Yan; Xu Chang; Cao Jia; Fu Yue; Chen Fenghua; Fan Feiyue

2013-01-01

Objective: To explore the regulative effect of non-homologous end joining (NHEJ)protein Ku70 on homologous recombination repair protein Rad51, and to investigate the synergistic mechanism of homologous recombination repair in combination with NHEJ. Methods: Observed Rad51 protein expression after transfect Ku70 small interfering RNA or Ku70 plasmid DNA into tumor cells using Western blot. Results: Expression of Rad51 was obviously reduced after pretreated with Ku70 small interfering RNA. And with the increasing expression of Ku70 protein after transfection of Ku70 plasmid DNA PGCsi3.0-hKu70 into tumor cell lines, the Rad51 protein expression was increased. Conclusion: Ku70 protein has regulating effect on gene expression of Rad51, and it might participate in the collaboration between homologous recombination repair and NHEJ. (authors)

Inclusion bodies of recombinant Epstein-Barr virus capsid antigen p18 as potential immobilized antigens in enzyme immunoassays for detection of nasopharyngeal carcinoma.

Science.gov (United States)

Lim, Chun Shen; Goh, Siang Ling; Kariapper, Leena; Krishnan, Gopala; Lim, Yat-Yuen; Ng, Ching Ching

2015-08-25

Development of indirect enzyme-linked immunosorbent assays (ELISAs) often utilizes synthetic peptides or recombinant proteins from Escherichia coli as immobilized antigens. Because inclusion bodies (IBs) formed during recombinant protein expression in E. coli are commonly thought as misfolded aggregates, only refolded proteins from IBs are used to develop new or in-house diagnostic assays. However, the promising utilities of IBs as nanomaterials and immobilized enzymes as shown in recent studies have led us to explore the potential use of IBs of recombinant Epstein-Barr virus viral capsid antigen p18 (VCA p18) as immobilized antigens in ELISAs for serologic detection of nasopharyngeal carcinoma (NPC). Thioredoxin fusion VCA p18 (VCA-Trx) and IBs of VCA p18 without fusion tags (VCA-IBs) were purified from E. coli. The diagnostic performances of IgG/VCA-IBs, IgG/VCA-Denat-IBs (using VCA-IBs coated in 8mol/l urea), IgG/VCA-Trx, and IgG/VCA-Peptide assays were compared by screening 100 NPC case-control pairs. The IgG/VCA-Denat-IBs assay showed the best area under the receiver operating characteristic curve (AUC: 0.802; p<0.05), while the AUCs for the IgG/VCA-IBs, IgG/VCA-Trx, and IgG/VCA-Peptide assays were comparable (AUC: 0.740, 0.727, and 0.741, respectively). We improved the diagnostic performance of the ELISA significantly using IBs of recombinant VCA p18. Copyright © 2015 Elsevier B.V. All rights reserved.

Purification and Characterization of Recombinant Vaccinia L1R Protein from Escherichia coli

Science.gov (United States)

2016-08-01

RECOMBINANT VACCINIA L1R PROTEIN FROM ESCHERICHIA COLI 1. INTRODUCTION 1.1 Background Vaccinia virus (VACV) is the active component of the...the preparation of the recombinant VACV L1R protein fragment by denaturing , refolding, and purifying material expressed into inclusion bodies in...PURIFICATION AND CHARACTERIZATION OF RECOMBINANT VACCINIA L1R PROTEIN FROM ESCHERICHIA COLI ECBC-TR-1370

Detoxifying Escherichia coli for endotoxin-free production of recombinant proteins.

Science.gov (United States)

Mamat, Uwe; Wilke, Kathleen; Bramhill, David; Schromm, Andra Beate; Lindner, Buko; Kohl, Thomas Andreas; Corchero, José Luis; Villaverde, Antonio; Schaffer, Lana; Head, Steven Robert; Souvignier, Chad; Meredith, Timothy Charles; Woodard, Ronald Wesley

2015-04-16

Lipopolysaccharide (LPS), also referred to as endotoxin, is the major constituent of the outer leaflet of the outer membrane of virtually all Gram-negative bacteria. The lipid A moiety, which anchors the LPS molecule to the outer membrane, acts as a potent agonist for Toll-like receptor 4/myeloid differentiation factor 2-mediated pro-inflammatory activity in mammals and, thus, represents the endotoxic principle of LPS. Recombinant proteins, commonly manufactured in Escherichia coli, are generally contaminated with endotoxin. Removal of bacterial endotoxin from recombinant therapeutic proteins is a challenging and expensive process that has been necessary to ensure the safety of the final product. As an alternative strategy for common endotoxin removal methods, we have developed a series of E. coli strains that are able to grow and express recombinant proteins with the endotoxin precursor lipid IVA as the only LPS-related molecule in their outer membranes. Lipid IVA does not trigger an endotoxic response in humans typical of bacterial LPS chemotypes. Hence the engineered cells themselves, and the purified proteins expressed within these cells display extremely low endotoxin levels. This paper describes the preparation and characterization of endotoxin-free E. coli strains, and demonstrates the direct production of recombinant proteins with negligible endotoxin contamination.

Recombinant Vaccinia Viruses Coding Transgenes of Apoptosis-Inducing Proteins Enhance Apoptosis But Not Immunogenicity of Infected Tumor Cells

Science.gov (United States)

Tkachenko, Anastasiya; Richter, Vladimir

2017-01-01

Genetic modifications of the oncolytic vaccinia virus (VV) improve selective tumor cell infection and death, as well as activation of antitumor immunity. We have engineered a double recombinant VV, coding human GM-CSF, and apoptosis-inducing protein apoptin (VV-GMCSF-Apo) for comparing with the earlier constructed double recombinant VV-GMCSF-Lact, coding another apoptosis-inducing protein, lactaptin, which activated different cell death pathways than apoptin. We showed that both these recombinant VVs more considerably activated a set of critical apoptosis markers in infected cells than the recombinant VV coding GM-CSF alone (VV-GMCSF-dGF): these were phosphatidylserine externalization, caspase-3 and caspase-7 activation, DNA fragmentation, and upregulation of proapoptotic protein BAX. However, only VV-GMCSF-Lact efficiently decreased the mitochondrial membrane potential of infected cancer cells. Investigating immunogenic cell death markers in cancer cells infected with recombinant VVs, we demonstrated that all tested recombinant VVs were efficient in calreticulin and HSP70 externalization, decrease of cellular HMGB1, and ATP secretion. The comparison of antitumor activity against advanced MDA-MB-231 tumor revealed that both recombinants VV-GMCSF-Lact and VV-GMCSF-Apo efficiently delay tumor growth. Our results demonstrate that the composition of GM-CSF and apoptosis-inducing proteins in the VV genome is very efficient tool for specific killing of cancer cells and for activation of antitumor immunity. PMID:28951871

Modulating secretory pathway pH by proton channel co-expression can increase recombinant protein stability in plants.

Science.gov (United States)

Jutras, Philippe V; D'Aoust, Marc-André; Couture, Manon M-J; Vézina, Louis-Philippe; Goulet, Marie-Claire; Michaud, Dominique; Sainsbury, Frank

2015-09-01

Eukaryotic expression systems are used for the production of complex secreted proteins. However, recombinant proteins face considerable biochemical challenges along the secretory pathway, including proteolysis and pH variation between organelles. As the use of synthetic biology matures into solutions for protein production, various host-cell engineering approaches are being developed to ameliorate host-cell factors that can limit recombinant protein quality and yield. We report the potential of the influenza M2 ion channel as a novel tool to neutralize the pH in acidic subcellular compartments. Using transient expression in the plant host, Nicotiana benthamiana, we show that ion channel expression can significantly raise pH in the Golgi apparatus and that this can have a strong stabilizing effect on a fusion protein separated by an acid-susceptible linker peptide. We exemplify the utility of this effect in recombinant protein production using influenza hemagglutinin subtypes differentially stable at low pH; the expression of hemagglutinins prone to conformational change in mildly acidic conditions is considerably enhanced by M2 co-expression. The co-expression of a heterologous ion channel to stabilize acid-labile proteins and peptides represents a novel approach to increasing the yield and quality of secreted recombinant proteins in plants and, possibly, in other eukaryotic expression hosts. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Recombinant protein scaffolds for tissue engineering

International Nuclear Information System (INIS)

Werkmeister, Jerome A; Ramshaw, John A M

2012-01-01

New biological materials for tissue engineering are now being developed using common genetic engineering capabilities to clone and express a variety of genetic elements that allow cost-effective purification and scaffold fabrication from these recombinant proteins, peptides or from chimeric combinations of these. The field is limitless as long as the gene sequences are known. The utility is dependent on the ease, product yield and adaptability of these protein products to the biomedical field. The development of recombinant proteins as scaffolds, while still an emerging technology with respect to commercial products, is scientifically superior to current use of natural materials or synthetic polymer scaffolds, in terms of designing specific structures with desired degrees of biological complexities and motifs. In the field of tissue engineering, next generation scaffolds will be the key to directing appropriate tissue regeneration. The initial period of biodegradable synthetic scaffolds that provided shape and mechanical integrity, but no biological information, is phasing out. The era of protein scaffolds offers distinct advantages, particularly with the combination of powerful tools of molecular biology. These include, for example, the production of human proteins of uniform quality that are free of infectious agents and the ability to make suitable quantities of proteins that are found in low quantity or are hard to isolate from tissue. For the particular needs of tissue engineering scaffolds, fibrous proteins like collagens, elastin, silks and combinations of these offer further advantages of natural well-defined structural scaffolds as well as endless possibilities of controlling functionality by genetic manipulation. (topical review)

Functions and structures of eukaryotic recombination proteins

International Nuclear Information System (INIS)

Ogawa, Tomoko

1994-01-01

We have found that Rad51 and RecA Proteins form strikingly similar structures together with dsDNA and ATP. Their right handed helical nucleoprotein filaments extend the B-form DNA double helixes to 1.5 times in length and wind the helix. The similarity and uniqueness of their structures must reflect functional homologies between these proteins. Therefore, it is highly probable that similar recombination proteins are present in various organisms of different evolutional states. We have succeeded to clone RAD51 genes from human, mouse, chicken and fission yeast genes, and found that the homologues are widely distributed in eukaryotes. The HsRad51 and MmRad51 or ChRad51 proteins consist of 339 amino acids differing only by 4 or 12 amino acids, respectively, and highly homologous to both yeast proteins, but less so to Dmcl. All of these proteins are homologous to the region from residues 33 to 240 of RecA which was named ''homologous core. The homologous core is likely to be responsible for functions common for all of them, such as the formation of helical nucleoprotein filament that is considered to be involved in homologous pairing in the recombination reaction. The mouse gene is transcribed at a high level in thymus, spleen, testis, and ovary, at lower level in brain and at a further lower level in some other tissues. It is transcribed efficiently in recombination active tissues. A clear functional difference of Rad51 homologues from RecA was suggested by the failure of heterologous genes to complement the deficiency of Scrad51 mutants. This failure seems to reflect the absence of a compatible partner, such as ScRad52 protein in the case of ScRad51 protein, between different species. Thus, these discoveries play a role of the starting point to understand the fundamental gene targeting in mammalian cells and in gene therapy. (J.P.N.)

Production of Polyclonal Antibodies to the Recombinant Potato virus M (PVM) Non-structural Triple Gene Block Protein 1 and Coat Protein

Czech Academy of Sciences Publication Activity Database

Čeřovská, Noemi; Moravec, Tomáš; Plchová, Helena; Hoffmeisterová, Hana; Dědič, P.

2012-01-01

Roč. 160, č. 5 (2012), s. 251-254 ISSN 0931-1785 R&D Projects: GA MŠk 1M06030 Institutional research plan: CEZ:AV0Z50380511 Keywords : Potato virus M * recombinant protein * coat protein Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.000, year: 2012

Pharmaceutical protein production by yeast: towards production of human blood proteins by microbial fermentation

DEFF Research Database (Denmark)

Martinez Ruiz, José Luis; Liu, Lifang; Petranovic, Dina

2012-01-01

Since the approval of recombinant insulin from Escherichia coli for its clinical use in the early 1980s, the amount of recombinant pharmaceutical proteins obtained by microbial fermentations has significantly increased. The recent advances in genomics together with high throughput analysis...... of recombinant therapeutics using yeast Saccharomyces cerevisiae as a model platform, and discusses the future potential of this platform for production of blood proteins and substitutes....

GroEL-GroES assisted folding of multiple recombinant proteins simultaneously over-expressed in Escherichia coli.

Science.gov (United States)

Goyal, Megha; Chaudhuri, Tapan K

2015-07-01

Folding of aggregation prone recombinant proteins through co-expression of chaperonin GroEL and GroES has been a popular practice in the effort to optimize preparation of functional protein in Escherichia coli. Considering the demand for functional recombinant protein products, it is desirable to apply the chaperone assisted protein folding strategy for enhancing the yield of properly folded protein. Toward the same direction, it is also worth attempting folding of multiple recombinant proteins simultaneously over-expressed in E. coli through the assistance of co-expressed GroEL-ES. The genesis of this thinking was originated from the fact that cellular GroEL and GroES assist in the folding of several endogenous proteins expressed in the bacterial cell. Here we present the experimental findings from our study on co-expressed GroEL-GroES assisted folding of simultaneously over-expressed proteins maltodextrin glucosidase (MalZ) and yeast mitochondrial aconitase (mAco). Both proteins mentioned here are relatively larger and aggregation prone, mostly form inclusion bodies, and undergo GroEL-ES assisted folding in E. coli cells during over-expression. It has been reported that the relative yield of properly folded functional forms of MalZ and mAco with the exogenous GroEL-ES assistance were comparable with the results when these proteins were overexpressed alone. This observation is quite promising and highlights the fact that GroEL and GroES can assist in the folding of multiple substrate proteins simultaneously when over-expressed in E. coli. This method might be a potential tool for enhanced production of multiple functional recombinant proteins simultaneously in E. coli. Copyright © 2015 Elsevier Ltd. All rights reserved.

Low-Molecular-Weight Peptides from Salmon Protein Prevent Obesity-Linked Glucose Intolerance, Inflammation, and Dyslipidemia in LDLR-/-/ApoB100/100 Mice.

Science.gov (United States)

Chevrier, Geneviève; Mitchell, Patricia L; Rioux, Laurie-Eve; Hasan, Fida; Jin, Tianyi; Roblet, Cyril Roland; Doyen, Alain; Pilon, Geneviève; St-Pierre, Philippe; Lavigne, Charles; Bazinet, Laurent; Jacques, Hélène; Gill, Tom; McLeod, Roger S; Marette, André

2015-07-01

We previously reported that fish proteins can alleviate metabolic syndrome (MetS) in obese animals and human subjects. We tested whether a salmon peptide fraction (SPF) could improve MetS in mice and explored potential mechanisms of action. ApoB(100) only, LDL receptor knockout male mice (LDLR(-/-)/ApoB(100/100)) were fed a high-fat and -sucrose (HFS) diet (25 g/kg sucrose). Two groups were fed 10 g/kg casein hydrolysate (HFS), and 1 group was additionally fed 4.35 g/kg fish oil (FO; HFS+FO). Two other groups were fed 10 g SPF/kg (HFS+SPF), and 1 group was additionally fed 4.35 g FO/kg (HFS+SPF+FO). A fifth (reference) group was fed a standard feed pellet diet. We assessed the impact of dietary treatments on glucose tolerance, adipose tissue inflammation, lipid homeostasis, and hepatic insulin signaling. The effects of SPF on glucose uptake, hepatic glucose production, and inducible nitric oxide synthase activity were further studied in vitro with the use of L6 myocytes, FAO hepatocytes, and J774 macrophages. Mice fed HFS+SPF or HFS+SPF+FO diets had lower body weight (protein effect, P = 0.024), feed efficiency (protein effect, P = 0.018), and liver weight (protein effect, P = 0.003) as well as lower concentrations of adipose tissue cytokines and chemokines (protein effect, P ≤ 0.003) compared with HFS and HFS+FO groups. They also had greater glucose tolerance (protein effect, P < 0.001), lower activation of the mammalian target of rapamycin complex 1/S6 kinase 1/insulin receptor substrate 1 (mTORC1/S6K1/IRS1) pathway, and increased insulin signaling in liver compared with the HFS and HFS+FO groups. The HFS+FO, HFS+SPF, and HFS+SPF+FO groups had lower plasma triglycerides (protein effect, P = 0.003; lipid effect, P = 0.002) than did the HFS group. SPF increased glucose uptake and decreased HGP and iNOS activation in vitro. SPF reduces obesity-linked MetS features in LDLR(-/-)/ApoB(100/100) mice. The anti-inflammatory and glucoregulatory properties of SPF were

Breaks in the 45S rDNA Lead to Recombination-Mediated Loss of Repeats

Directory of Open Access Journals (Sweden)

Daniël O. Warmerdam

2016-03-01

Full Text Available rDNA repeats constitute the most heavily transcribed region in the human genome. Tumors frequently display elevated levels of recombination in rDNA, indicating that the repeats are a liability to the genomic integrity of a cell. However, little is known about how cells deal with DNA double-stranded breaks in rDNA. Using selective endonucleases, we show that human cells are highly sensitive to breaks in 45S but not the 5S rDNA repeats. We find that homologous recombination inhibits repair of breaks in 45S rDNA, and this results in repeat loss. We identify the structural maintenance of chromosomes protein 5 (SMC5 as contributing to recombination-mediated repair of rDNA breaks. Together, our data demonstrate that SMC5-mediated recombination can lead to error-prone repair of 45S rDNA repeats, resulting in their loss and thereby reducing cellular viability.

Recombinant proteins from plants: production and isolation of clinically useful compounds

National Research Council Canada - National Science Library

Cunningham, Charles; Porter, Andrew J. R

1998-01-01

... of recombinant proteins for use as specialist industrial or therapeutic biomolecules. The intention of Recombinant Proteins from Plants is to provide comprehensive and detailed protocols covering all the latest molecular approaches. Because the production oftransgenic plants has become routine in many laboratories, coverage is also given to some of the more "...

Inclusion bodies as potential vehicles for recombinant protein delivery into epithelial cells

Science.gov (United States)

2012-01-01

Background We present the potential of inclusion bodies (IBs) as a protein delivery method for polymeric filamentous proteins. We used as cell factory a strain of E. coli, a conventional host organism, and keratin 14 (K14) as an example of a complex protein. Keratins build the intermediate filament cytoskeleton of all epithelial cells. In order to build filaments, monomeric K14 needs first to dimerize with its binding partner (keratin 5, K5), which is then followed by heterodimer assembly into filaments. Results K14 IBs were electroporated into SW13 cells grown in culture together with a “reporter” plasmid containing EYFP labeled keratin 5 (K5) cDNA. As SW13 cells do not normally express keratins, and keratin filaments are built exclusively of keratin heterodimers (i.e. K5/K14), the short filamentous structures we obtained in this study can only be the result of: a) if both IBs and plasmid DNA are transfected simultaneously into the cell(s); b) once inside the cells, K14 protein is being released from IBs; c) released K14 is functional, able to form heterodimers with EYFP-K5. Conclusions Soluble IBs may be also developed for complex cytoskeletal proteins and used as nanoparticles for their delivery into epithelial cells. PMID:22624805

Mycobacterium tuberculosis HspX/EsxS Fusion Protein: Gene Cloning, Protein Expression, and Purification in Escherichia coli.

Science.gov (United States)

Khademi, Farzad; Yousefi-Avarvand, Arshid; Derakhshan, Mohammad; Meshkat, Zahra; Tafaghodi, Mohsen; Ghazvini, Kiarash; Aryan, Ehsan; Sankian, Mojtaba

2017-10-01

The purpose of this study was to clone, express, and purify a novel multidomain fusion protein of Micobacterium tuberculosis (Mtb) in a prokaryotic system. An hspX/esxS gene construct was synthesized and ligated into a pGH plasmid, E. coli TOP10 cells were transformed, and the vector was purified. The vector containing the construct and pET-21b (+) plasmid were digested with the same enzymes and the construct was ligated into pET-21b (+). The accuracy of cloning was confirmed by colony PCR and sequencing. E. coli BL21 cells were transformed with the pET-21b (+)/hspX/esxS expression vector and protein expression was evaluated. Finally, the expressed fusion protein was purified on a Ni-IDA column and verified by SDS-PAGE and western blotting. The hspX/esxS gene construct was inserted into pET-21b (+) and recombinant protein expression was induced with IPTG in E. coli BL21 cells. Various concentrations of IPTG were tested to determine the optimum concentration for expression induction. The recombinant protein was expressed in insoluble inclusion bodies. Three molar guanidine HCl was used to solubilize the insoluble protein. An HspX/EsxS Mtb fusion protein was expressed in E. coli and the recombinant protein was purified. After immunological analysis, the HspX/EsxS fusion protein might be an anti-tuberculosis vaccine candidate in future clinical trial studies.

Production of a Recombinant Dengue Virus 2 NS5 Protein and Potential Use as a Vaccine Antigen.

Science.gov (United States)

Alves, Rúbens Prince Dos Santos; Pereira, Lennon Ramos; Fabris, Denicar Lina Nascimento; Salvador, Felipe Scassi; Santos, Robert Andreata; Zanotto, Paolo Marinho de Andrade; Romano, Camila Malta; Amorim, Jaime Henrique; Ferreira, Luís Carlos de Souza

2016-06-01

Dengue fever is caused by any of the four known dengue virus serotypes (DENV1 to DENV4) that affect millions of people worldwide, causing a significant number of deaths. There are vaccines based on chimeric viruses, but they still are not in clinical use. Anti-DENV vaccine strategies based on nonstructural proteins are promising alternatives to those based on whole virus or structural proteins. The DENV nonstructural protein 5 (NS5) is the main target of anti-DENV T cell-based immune responses in humans. In this study, we purified a soluble recombinant form of DENV2 NS5 expressed in Escherichia coli at large amounts and high purity after optimization of expression conditions and purification steps. The purified DENV2 NS5 was recognized by serum from DENV1-, DENV2-, DENV3-, or DENV4-infected patients in an epitope-conformation-dependent manner. In addition, immunization of BALB/c mice with NS5 induced high levels of NS5-specific antibodies and expansion of gamma interferon- and tumor necrosis factor alpha-producing T cells. Moreover, mice immunized with purified NS5 were partially protected from lethal challenges with the DENV2 NGC strain and with a clinical isolate (JHA1). These results indicate that the recombinant NS5 protein preserves immunological determinants of the native protein and is a promising vaccine antigen capable of inducing protective immune responses. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Study of lymphocyte sensitization to protein S-100 in the patients with cerebrovascular diseases, suffered due to Chernobyl NPP accident

International Nuclear Information System (INIS)

Khomenko, V.Yi.

2004-01-01

Among the persons with cerebrovascular diseases, suffered due to Chernobyl NPP accident two groups of patients were revealed: with DNA coloration coefficients in response to protein S-100 stimulation below and above 1. Patients with DNA coloration coefficients <1 were older, they had statistically significant lower monocytes and T-activated lymphocytes absolute counts as well as increased content of cholesterol-2 and circulating immune complexes. Charges found there suggested possible existence of different pathways of immune response to antigenic stimulation by S-100 protein

The correlation of serum S100β protein levels and hippocampal Seladin-1 gene expression in a rat model of sporadic Alzheimer\\\\\\'s disease

Directory of Open Access Journals (Sweden)

Soheila Hosseinzadeh

2015-11-01

Full Text Available Background: Seladin-1 protein protects the neural cells against amyloid beta toxicity and its expression decreased in vulnerable regions of Alzheimer's disease (AD brains. On the other hand, changes in serum levels of S100 have been considered as a marker of brain damage in neurodegenerative diseases. Furthermore, this study was carried out to determine the relation between the change profile of serum S100β protein levels and hippocampal Seladin-1 gene expression in a rat model of sporadic AD. Methods: In this experimental study that established in Department of Neuroscience, School of Advanced Technologies in Medicine, Tehran University of Medical Science, from March 2011 to April 2013, 72 animals were randomly divided into control, 4, 7, 14, and 21days ICV-STZ/Saline administrated rats. Alzheimer's model was induced by intracerebroventricular (ICV injections of streptozotocin (STZ [3 mg/kg] on days 1 and 3. Serum levels of S100β and hippocampal Seladin-1 gene expression were evalu-ated in experimental groups. The initial and step-through latencies (STL were deter-mined using passive avoidance test. Results: Serum levels of S100β were significantly different between the STZ-7 day and STZ-14 day groups in comparison with the control, saline and STZ-4 day groups. As well as, there was a significant difference between the STZ-7 day group in comparison with the STZ-14 day and STZ-21 day groups (P=0.0001. Hippocampal Seladin-1 gene expression in STZ-14 day and STZ-21 day groups significantly decreased as compared to the control, saline and STZ-4 day groups (P=0.0001. However, significant correla-tion was detected between serum S100β protein decrement and Seladin-1 down regula-tion (P=0.001. Also, the STL was significantly decreased in 21 days ICV-STZ adminis-trated rats as compared to the control or saline groups (P=0.001. Conclusion: Monitoring the changes of serum S100β protein levels by relationship with changes in hippocampal Seladin-1

S100B proteins in febrile seizures

DEFF Research Database (Denmark)

Mikkonen, Kirsi; Pekkala, Niina; Pokka, Tytti

2011-01-01

at the hospital after FS and S100B concentration in serum (r=-0.130, P=0.28) or in cerebrospinal fluid samples (r=-0.091, P=0.52). Our findings indicate that FS does not cause significant blood-brain barrier openings, and increase the evidence that these seizures are relatively harmless for the developing brain....

Use of a protein engineering strategy to overcome limitations in the production of "Difficult to Express" recombinant proteins.

Science.gov (United States)

Hussain, Hirra; Fisher, David I; Abbott, W Mark; Roth, Robert G; Dickson, Alan J

2017-10-01

Certain recombinant proteins are deemed "difficult to express" in mammalian expression systems requiring significant cell and/or process engineering to abrogate expression bottlenecks. With increasing demand for the production of recombinant proteins in mammalian cells, low protein yields can have significant consequences for industrial processes. To investigate the molecular mechanisms that restrict expression of recombinant proteins, naturally secreted model proteins were analyzed from the tissue inhibitors of metalloproteinase (TIMP) protein family. In particular, TIMP-2 and TIMP-3 were subjected to detailed study. TIMP proteins share significant sequence homology (∼50% identity and ∼70% similarity in amino acid sequence). However, they show marked differences in secretion in mammalian expression systems despite this extensive sequence homology. Using these two proteins as models, this study characterized the molecular mechanisms responsible for poor recombinant protein production. Our results reveal that both TIMP-2 and TIMP-3 are detectable at mRNA and protein level within the cell but only TIMP-2 is secreted effectively into the extracellular medium. Analysis of protein localization and the nature of intracellular protein suggest TIMP-3 is severely limited in its post-translational processing. To overcome this challenge, modification of the TIMP-3 sequence to include a furin protease-cleavable pro-sequence resulted in secretion of the modified TIMP-3 protein, however, incomplete processing was observed. Based on the TIMP-3 data, the protein engineering approach was optimized and successfully applied in combination with cell engineering, the overexpression of furin, to another member of the TIMP protein family (the poorly expressed TIMP-4). Use of the described protein engineering strategy resulted in successful secretion of poorly (TIMP-4) and non-secreted (TIMP-3) targets, and presents a novel strategy to enhance the production of "difficult" recombinant

Recombinant protein production data after expression in the bacterium Escherichia coli

Directory of Open Access Journals (Sweden)

J. Enrique Cantu-Bustos

2016-06-01

Full Text Available Fusion proteins have become essential for the expression and purification of recombinant proteins in Escherichia coli. The metal-binding protein CusF has shown several features that make it an attractive fusion protein and affinity tag: "Expression and purification of recombinant proteins in Escherichia coli tagged with the metal-binding protein CusF" (Cantu-Bustos et al., 2016 [1]. Here we present accompanying data from protein expression experiments; we tested different protein tags, temperatures, expression times, cellular compartments, and concentrations of inducer in order to obtain soluble protein and low formation of inclusion bodies. Additionally, we present data from the purification of the green fluorescent protein (GFP tagged with CusF, using Ag(I metal affinity chromatography.

Analysis of recombinant proteins by isoelectric focusing in immobilized pH gradients

NARCIS (Netherlands)

Bischoff, Rainer; Roecklin, D.; Roitsch, C.

1992-01-01

Isoelectric focusing in immobilized pH gradients (IEF-IPG) was used to analyze three different recombinant proteins. Recombinant leech hirudin (65 amino acids, three disulfide bonds) expressed in Saccharomyces cerevisiae as a secreted protein and purified by anion-exchange and reversed-phase

Breaks in the 45S rDNA Lead to Recombination-Mediated Loss of Repeats.

Science.gov (United States)

Warmerdam, Daniël O; van den Berg, Jeroen; Medema, René H

2016-03-22

rDNA repeats constitute the most heavily transcribed region in the human genome. Tumors frequently display elevated levels of recombination in rDNA, indicating that the repeats are a liability to the genomic integrity of a cell. However, little is known about how cells deal with DNA double-stranded breaks in rDNA. Using selective endonucleases, we show that human cells are highly sensitive to breaks in 45S but not the 5S rDNA repeats. We find that homologous recombination inhibits repair of breaks in 45S rDNA, and this results in repeat loss. We identify the structural maintenance of chromosomes protein 5 (SMC5) as contributing to recombination-mediated repair of rDNA breaks. Together, our data demonstrate that SMC5-mediated recombination can lead to error-prone repair of 45S rDNA repeats, resulting in their loss and thereby reducing cellular viability. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Unusual Self-Assembly of the Recombinant Chlamydia trachomatis Major Outer Membrane Protein-Based Fusion Antigen CTH522 Into Protein Nanoparticles

DEFF Research Database (Denmark)

Rose, Fabrice; Karlsen, Kasper; Jensen, Pernille

2018-01-01

Sexually transmitted Chlamydia trachomatis (Ct) infects more than 100 million people annually, and untreated chlamydia infections can cause severe complications. Therefore, there is an urgent need for a chlamydia vaccine. The Ct major outer membrane protein (MOMP) is highly immunogenic but is a c......Sexually transmitted Chlamydia trachomatis (Ct) infects more than 100 million people annually, and untreated chlamydia infections can cause severe complications. Therefore, there is an urgent need for a chlamydia vaccine. The Ct major outer membrane protein (MOMP) is highly immunogenic...... but is a challenging vaccine candidate by being an integral membrane protein, and the immunogenicity depends on a correctly folded structure. We investigated the biophysical properties of the recombinant MOMP-based fusion antigen CTH522, which is tested in early human clinical trials. It consists of a truncated......-defined secondary structural elements, and no thermal transitions were measurable. Chemical unfolding resulted monomers that upon removal of the denaturant self-assembled into higher order structures, comparable to the structure of the native protein. The conformation of CTH522 in nanoparticles is thus not entirely...

Roadmap to developing a recombinant coronavirus S protein receptor-binding domain vaccine for severe acute respiratory syndrome

Science.gov (United States)

Jiang, Shibo; Bottazzi, Maria Elena; Du, Lanying; Lustigman, Sara; Tseng, Chien-Te Kent; Curti, Elena; Jones, Kathryn; Zhan, Bin; Hotez, Peter J

2013-01-01

A subunit vaccine, RBD-S, is under development to prevent severe acute respiratory syndrome (SARS) caused by SARS coronavirus (SARS-CoV), which is classified by the US NIH as a category C pathogen. This vaccine is comprised of a recombinant receptor-binding domain (RBD) of the SARS-CoV spike (S) protein and formulated on alum, together with a synthetic glucopyranosyl lipid A. The vaccine would induce neutralizing antibodies without causing Th2-type immunopathology. Vaccine development is being led by the nonprofit product development partnership; Sabin Vaccine Institute and Texas Children’s Hospital Center for Vaccine Development in collaboration with two academic partners (the New York Blood Center and University of Texas Medical Branch); an industrial partner (Immune Design Corporation); and Walter Reed Army Institute of Research. A roadmap for the product development of the RBD-S SARS vaccine is outlined with a goal to manufacture the vaccine for clinical testing within the next 5 years. PMID:23252385

Production, purification and immunogenicity of recombinant Ebola virus proteins - A comparison of Freund's adjuvant and adjuvant system 03.

Science.gov (United States)

Melén, Krister; Kakkola, Laura; He, Felix; Airenne, Kari; Vapalahti, Olli; Karlberg, Helen; Mirazimi, Ali; Julkunen, Ilkka

2017-04-01

There is an urgent need for Ebola virus (EBOV) proteins, EBOV-specific antibodies and recombinant antigens to be used in diagnostics and as potential vaccine candidates. Our objective was to produce and purify recombinant proteins for immunological assays and for the production of polyclonal EBOV specific antibodies. In addition, a limited comparison of the adjuvant effects of Freund's complete adjuvant (FCA) and adjuvant system 03 (AS03) was carried out. Recombinant EBOV GST-VP24, -VP30, -VP35, -VP40 and -NP were produced in E. coli and purified with affinity chromatography followed by preparative gel electrophoresis. Recombinant EBOV GP-His was produced in Sf9 insect cells and purified by preparative gel electrophoresis. To compare the adjuvant effect of FCA and AS03, 12 rabbits were immunized four times with one of the six recombinant EBOV proteins using FCA or AS03. In addition, three guinea pigs were immunized with EBOV VP24 using FCA. With the exception of sera from two rabbits immunized with GST-VP24, the antisera against all other EBOV proteins showed very high and specific antibody responses after three to four immunizations. The adjuvant effect of AS03 was comparable to that of FCA. The produced antibodies recognized the corresponding EBOV proteins in wild type EBOV-infected cells. Copyright © 2016 Elsevier B.V. All rights reserved.

Solving the crystal structure of human calcium-free S100Z: the siege and conquer of one of the last S100 family strongholds.

Science.gov (United States)

Calderone, V; Fragai, M; Gallo, G; Luchinat, C

2017-06-01

The X-ray structure of human apo-S100Z has been solved and compared with that of the zebrafish calcium-bound S100Z, which is the closest in sequence. Human apo-S100A12, which shows only 43% sequence identity to human S100Z, has been used as template model to solve the crystallographic phase problem. Although a significant buried surface area between the two physiological dimers is present in the asymmetric unit of human apo-S100Z, the protein does not form the superhelical arrangement in the crystal as observed for the zebrafish calcium-bound S100Z and human calcium-bound S100A4. These findings further demonstrate that calcium plays a fundamental role in triggering quaternary structure formation in several S100s. Solving the X-ray structure of human apo-S100Z by standard molecular replacement procedures turned out to be a challenge and required trying different models and different software tools among which only one was successful. The model that allowed structure solution was that with one of the lowest sequence identity with the target protein among the S100 family in the apo state. Based on the previously solved zebrafish holo-S100Z, a putative human holo-S100Z structure has been then calculated through homology modeling; the differences between the experimental human apo and calculated holo structure have been compared to those existing for other members of the family.

Fcγ1 fragment of IgG1 as a powerful affinity tag in recombinant Fc-fusion proteins: immunological, biochemical and therapeutic properties.

Science.gov (United States)

Soleimanpour, Saman; Hassannia, Tahereh; Motiee, Mahdieh; Amini, Abbas Ali; Rezaee, S A R

2017-05-01

Affinity tags are vital tools for the production of high-throughput recombinant proteins. Several affinity tags, such as the hexahistidine tag, maltose-binding protein, streptavidin-binding peptide tag, calmodulin-binding peptide, c-Myc tag, glutathione S-transferase and FLAG tag, have been introduced for recombinant protein production. The fragment crystallizable (Fc) domain of the IgG1 antibody is one of the useful affinity tags that can facilitate detection, purification and localization of proteins and can improve the immunogenicity, modulatory effects, physicochemical and pharmaceutical properties of proteins. Fcγ recombinant forms a group of recombinant proteins called Fc-fusion proteins (FFPs). FFPs are widely used in drug discovery, drug delivery, vaccine design and experimental research on receptor-ligand interactions. These fusion proteins have become successful alternatives to monoclonal antibodies for drug developments. In this review, the physicochemical, biochemical, immunological, pharmaceutical and therapeutic properties of recombinant FFPs were discussed as a new generation of bioengineering strategies.

Cultivating Insect Cells To Produce Recombinant Proteins

Science.gov (United States)

Spaulding, Glenn; Goodwin, Thomas; Prewett, Tacey; Andrews, Angela; Francis, Karen; O'Connor, Kim

1996-01-01

Method of producing recombinant proteins involves growth of insect cells in nutrient solution in cylindrical bioreactor rotating about cylindrical axis, oriented horizontally and infecting cells with viruses into which genes of selected type cloned. Genes in question those encoding production of desired proteins. Horizontal rotating bioreactor preferred for use in method, denoted by acronym "HARV", described in "High-Aspect-Ratio Rotating Cell-Culture Vessel" (MSC-21662).

Recombinant Protein Production of Earthworm Lumbrokinase for Potential Antithrombotic Application

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Kevin Yueju Wang

2013-01-01

Full Text Available Earthworms have been used as a traditional medicine in China, Japan, and other Far East countries for thousands of years. Oral administration of dry earthworm powder is considered as a potent and effective supplement for supporting healthy blood circulation. Lumbrokinases are a group of enzymes that were isolated and purified from different species of earthworms. These enzymes are recognized as fibrinolytic agents that can be used to treat various conditions associated with thrombosis. Many lumbrokinase (LK genes have been cloned and characterized. Advances in genetic technology have provided the ability to produce recombinant LK and have made it feasible to purify a single lumbrokinase enzyme for potential antithrombotic application. In this review, we focus on expression systems that can be used for lumbrokinase production. In particular, the advantages of using a transgenic plant system to produce edible lumbrokinase are described.

Purification and characterization of recombinant protein kinase CK2 from Zea mays expressed in Escherichia coli

DEFF Research Database (Denmark)

Riera, Marta; Pages, Montserrat; Issinger, Olaf Georg

2003-01-01

Recombinant protein kinase subunits rmCK2alpha-1 and rmCK2beta-1 from Zea mays were expressed separately in Escherichia coli and assembled to a fully active tetrameric holoenzyme complex in vitro. The obtained maize holoenzyme was purified to homogeneity, biochemically characterized, and compared...... to CK2 from human. Kinetic measurements of the recombinant maize holoenzyme (rmCK2) revealed k(cat) values for ATP and GTP of 4 and 2s(-1), respectively; whereas the recombinant maize catalytic subunit showed almost equal values for ATP and GTP, i.e., ca. 0.8s(-1). A comparison of the k(cat)/K(m) ratio...

Anti-EGFR-iRGD recombinant protein conjugated silk fibroin nanoparticles for enhanced tumor targeting and antitumor efficiency

Directory of Open Access Journals (Sweden)

Bian X

2016-05-01

Full Text Available Xinyu Bian,* Puyuan Wu,* Huizi Sha, Hanqing Qian, Qing Wang, Lei Cheng, Yang Yang, Mi Yang, Baorui LiuComprehensive Cancer Center of Drum-Tower Hospital, Medical School of Nanjing University, Clinical Cancer Institute of Nanjing University, Nanjing, People’s Republic of China*These authors contributed equally to this workAbstract: In this study, we report a novel kind of targeting with paclitaxel (PTX-loaded silk fibroin nanoparticles conjugated with iRGD–EGFR nanobody recombinant protein (anti-EGFR-iRGD. The new nanoparticles (called A-PTX-SF-NPs were prepared using the carbodiimide-mediated coupling procedure and their characteristics were evaluated. The cellular cytotoxicity and cellular uptake of A-PTX-SF-NPs were also investigated. The results in vivo suggested that NPs conjugated with the recombinant protein exhibited more targeting and anti-neoplastic property in cells with high EGFR expression. In the in vivo antitumor efficacy assay, the A-PTX-SF-NPs group showed slower tumor growth and smaller tumor volumes than PTX-SF-NPs in a HeLa xenograft mouse model. A real-time near-infrared fluorescence imaging study showed that A-PTX-SF-NPs could target the tumor more effectively. These results suggest that the anticancer activity and tumor targeting of A-PTX-SF-NPs were superior to those of PTX-SF-NPs and may have the potential to be used for targeted delivery for tumor therapies. Keywords: EGFR, nanobody, iRGD, recombinant protein, targeting drug carriers, antitumor efficiency

The Effect of Erythropoietin on S100 Protein Expression in Cochlea After Acoustic Overstimulation: An Experimental Study

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Gulsen Gurgen

2014-03-01

Full Text Available Aim: To investigate the effect of Erythropoietin on acoustically overstimulated rat spiral ganglion neurons (SGNs using S100 protein immunostaining.Material and Method: Twenty-two Wistar albino rats were divided into three groups: healthy control group (n=7, Saline solution (n=7 and Erythropoietin injection groups (n=8. Saline solution and Erythropoietin injection groups received white noise (100 dB SPL for 3 hours. Cochlear sections were stained by silver staining technique and immunostained by S100 antibody. Results: Histochemical analysis of silver staining sections revealed normal structure and a weak staining in SGNs of healthy control group. However, dark-black cytoplasmic staining, cellular shrinkage and degeneration were detected in saline injection group. On the other hand, a few weakly stained neurons were observed in erythropoietin injection group. S100 staining demonstrated strong reaction in Schwann cells and myelin sheaths of SGNs in healthy control group (p<0.05. In saline solution injection group, Schwann cells showed moderate S100 reaction and other regions of SGNs showed weak reaction (p<0.05. In erythropoietin injection group, strong S100 expression almost similar to the healthy control group was determined, although there was an occasional decrease. Discussion: Erythropoetin may prevent noise induced SGN degeneration via protecting the Schwann cells in rat cochlea.

S100A14 is a novel independent prognostic biomarker in the triple-negative breast cancer subtype

DEFF Research Database (Denmark)

Ehmsen, Sidse; Hansen, Lea Tykgaard; Bak, Martin

2015-01-01

Triple-negative breast cancer (TNBC) represents a heterogeneous subgroup with generally poor outcome and lack of an effective targeted therapy. Prognostic or predictive biomarkers to guide treatment decisions for this group of patients are needed. To evaluate the potential of S100A14 protein...... as a novel biomarker in TNBC, the protein expression of S100A14 was correlated with clinical outcomes in a Pilot Sample set and a Danish cohort of predominantly TNBC patients. Kaplan-Meier analysis identified a prognostic impact of S100A14 on disease-free survival and overall survival, showing that tumors......-), had equally poor outcomes as those with tumor-positive axillary lymph nodes (N+), while TNBC/N- patients with low S100A14 expression had a significantly better disease free survival (p = 0.013). Multivariate analysis revealed that S100A14 is an independent prognostic factor for TNBC patients (p = 0...

Exploiting translational coupling for the selection of cells producing toxic recombinant proteins from expression vectors.

Science.gov (United States)

Tagliavia, Marcello; Cuttitta, Angela

2016-01-01

High rates of plasmid instability are associated with the use of some expression vectors in Escherichia coli, resulting in the loss of recombinant protein expression. This is due to sequence alterations in vector promoter elements caused by the background expression of the cloned gene, which leads to the selection of fast-growing, plasmid-containing cells that do not express the target protein. This phenomenon, which is worsened when expressing toxic proteins, results in preparations containing very little or no recombinant protein, or even in clone loss; however, no methods to prevent loss of recombinant protein expression are currently available. We have exploited the phenomenon of translational coupling, a mechanism of prokaryotic gene expression regulation, in order to select cells containing plasmids still able to express recombinant proteins. Here we designed an expression vector in which the cloned gene and selection marker are co-expressed. Our approach allowed for the selection of the recombinant protein-expressing cells and proved effective even for clones encoding toxic proteins.

[Study on the anti-NTHi infection of Hap recombinant protein in vivo].

Science.gov (United States)

Li, Wan-yi; Wang, Bao-ning; Zuo, Feng-qiong; Zeng, Wei; Feng, Feng; Kuang, Yu; Jiang, Zhong-hua; Li, Ming-yuan

2010-07-01

To observe the immune effect of Hap recombinant protein on murine model of bronchopneumonia infected with NTHi, and explore the mechanism about the anti-NTHi infection. The C57BL/6 mice intranasally immunized with purified Hap recombinant protein and CT-B were challenged by NTHi encased in agar beads. The immunifaction of anti-infection was observed through encocyte counting of BALF, bacteria detection of lung and the pathologyical change of lung tissue. In the challenge with NTHi experiment, the inflammatory exudation of the infected murine and pathological change of lung tissue was relieved by combined immunization of Hap recombinant protein and CT-B, and quantity of NTHi in lung of the infected murine was reduced obviously. The Hap recombinant protein also had good ability of anti-NTHi infection in the murine model of NTHi bronchopneumonia. This study could offer the oretical and experimental basis for development of new vaccine against NTHi.

Can S100B predict cerebral vasospasms in patients suffering from subarachnoid hemorrhage?

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Moshgan eAmiri

2013-06-01

Full Text Available Background: Protein S100B has proven to be a useful biomarker for cerebral damages. Increased levels of serum and CSF S100B have been shown in patients suffering subarachnoid hemorrhage, severe head injury and stroke. In patients with subarachnoid hemorrhage, the course of S100B levels has been correlated with neurological deficits and outcome. Cerebral vasospasm is a major contributor to morbidity and mortality. The primary aim of this study was to investigate the potential of S100B protein as a predictor of cerebral vasospasm in patients with severe subarachnoid hemorrhage.Methods: Patients with SAH, Fisher grade 3 and 4, were included in the study. Five samples of CSF and serum S100B were collected from each patient. The first sample (baseline sample was drawn within the first three days following ictus and the following four samples, once a day on days 5 to 8, with day of ictus defined as day 1. Clinical suspicion of cerebral vasospasm confirmed by computed tomography angiography was used to diagnose cerebral vasospasm.Results: A total of 18 patients were included. Five patients (28 % developed cerebral vasospasm, two (11 % developed ventriculitis. There were no significant differences between S100B for those with and without vasospasm. Serum S100B levels in patients with vasospasm were slightly lower within the first 5 days following ictus, compared to patients without vasospasm. Two out of 5 patients had elevated and increasing serum S100B prior to vasospasm. Only one showed a peak level of S100B one day before vasospasm could be diagnosed. Due to the low number of patients in the study, statistical significance could not be reached. Conclusion: Neither serum nor CSF S100B can be used as predictor of cerebral vasospasm in patients suffering from subarachnoid hemorrhage.

Dynamic change of serum protein S100b and its clinical significance in patients with traumatic brain injury

Institute of Scientific and Technical Information of China (English)

CHEN Da-qing; ZHU Lie-lie

2005-01-01

Objective: To analyze the dynamic change of serum protein S100b in patients with traumatic brain injury and its clinical value in assessing brain damage. Methods: According to Glasgow coma scale (GCS), 102 cases of traumatic brain injury were divided into mild brain injury group (GCS≥13, n=31, Group A), moderate brain injury group (8S100b concentrations were analyzed by enzyme-linked immunosorbent assay (ELISA) in blood samples taken on admission, 12 h, 24 h, 48 h, 72 h and 7 days after traumatic brain injury. Results: The severe brain injury group showed significantly higher concentration of serum S100b, with earlier increase and longer duration, than the mild and moderate brain injury groups. The patients with higher S100b exhibited lower GCS scores and poor clinical prognosis. The increase in S100b could emerge before clinical image evidence indicated so. Conclusions: Serum S100b can be used as a sensitive index for assessment and prediction of traumatic brain injury severity and prognosis.

Finding trans-regulatory genes and protein complexes modulating meiotic recombination hotspots of human, mouse and yeast.

Science.gov (United States)

Wu, Min; Kwoh, Chee-Keong; Li, Xiaoli; Zheng, Jie

2014-09-11

The regulatory mechanism of recombination is one of the most fundamental problems in genomics, with wide applications in genome wide association studies (GWAS), birth-defect diseases, molecular evolution, cancer research, etc. Recombination events cluster into short genomic regions called "recombination hotspots". Recently, a zinc finger protein PRDM9 was reported to regulate recombination hotspots in human and mouse genomes. In addition, a 13-mer motif contained in the binding sites of PRDM9 is found to be enriched in human hotspots. However, this 13-mer motif only covers a fraction of hotspots, indicating that PRDM9 is not the only regulator of recombination hotspots. Therefore, the challenge of discovering other regulators of recombination hotspots becomes significant. Furthermore, recombination is a complex process. Hence, multiple proteins acting as machinery, rather than individual proteins, are more likely to carry out this process in a precise and stable manner. Therefore, the extension of the prediction of individual trans-regulators to protein complexes is also highly desired. In this paper, we introduce a pipeline to identify genes and protein complexes associated with recombination hotspots. First, we prioritize proteins associated with hotspots based on their preference of binding to hotspots and coldspots. Second, using the above identified genes as seeds, we apply the Random Walk with Restart algorithm (RWR) to propagate their influences to other proteins in protein-protein interaction (PPI) networks. Hence, many proteins without DNA-binding information will also be assigned a score to implicate their roles in recombination hotspots. Third, we construct sub-PPI networks induced by top genes ranked by RWR for various species (e.g., yeast, human and mouse) and detect protein complexes in those sub-PPI networks. The GO term analysis show that our prioritizing methods and the RWR algorithm are capable of identifying novel genes associated with

Identification of Protein-Protein Interactions with Glutathione-S-Transferase (GST) Fusion Proteins.

Science.gov (United States)

Einarson, Margret B; Pugacheva, Elena N; Orlinick, Jason R

2007-08-01

INTRODUCTIONGlutathione-S-transferase (GST) fusion proteins have had a wide range of applications since their introduction as tools for synthesis of recombinant proteins in bacteria. GST was originally selected as a fusion moiety because of several desirable properties. First and foremost, when expressed in bacteria alone, or as a fusion, GST is not sequestered in inclusion bodies (in contrast to previous fusion protein systems). Second, GST can be affinity-purified without denaturation because it binds to immobilized glutathione, which provides the basis for simple purification. Consequently, GST fusion proteins are routinely used for antibody generation and purification, protein-protein interaction studies, and biochemical analysis. This article describes the use of GST fusion proteins as probes for the identification of protein-protein interactions.

Recombinant proteins of helminths with immunoregulatory properties and their possible therapeutic use.

Science.gov (United States)

Nascimento Santos, Leonardo; Carvalho Pacheco, Luis Gustavo; Silva Pinheiro, Carina; Alcantara-Neves, Neuza Maria

2017-02-01

The inverse relationship between helminth infections and the development of immune-mediated diseases is a cornerstone of the hygiene hypothesis and studies were carried out to elucidate the mechanisms by which helminth-derived molecules can suppress immunological disorders. These studies have fostered the idea that parasitic worms may be used as a promising therapeutic alternative for prevention and treatment of immune-mediated diseases. We discuss the current approaches for identification of helminth proteins with potential immunoregulatory properties, including the strategies based on high-throughput technologies. We also explore the methodological approaches and expression systems used for production of the recombinant forms of more than 20 helminth immunomodulatory proteins, besides their performances when evaluated as immunotherapeutic molecules to treat different immune-mediated conditions, including asthma and inflammatory bowel diseases. Finally, we discuss the perspectives of using these parasite-derived recombinant molecules as tools for future immunotherapy and immunoprophylaxis of human inflammatory diseases. Copyright © 2016. Published by Elsevier B.V.

Production, purification and oxidative folding of the mouse recombinant prion protein

Czech Academy of Sciences Publication Activity Database

Pavlíček, A.; Bednárová, Lucie; Holada, K.

2007-01-01

Roč. 52, č. 4 (2007), s. 391-397 ISSN 0015-5632 R&D Projects: GA ČR GD310/05/H533 Grant - others:GA ČR(CZ) GA310/04/0419 Institutional research plan: CEZ:AV0Z40550506 Keywords : recombinant prion protein * production * purification * folding Subject RIV: CE - Biochemistry Impact factor: 0.989, year: 2007 http://www.biomed.cas.cz/mbu/folia/

Cloning an artificial gene encoding angiostatic anginex: From designed peptide to functional recombinant protein

International Nuclear Information System (INIS)

Brandwijk, Ricardo J.M.G.E.; Nesmelova, Irina; Dings, Ruud P.M.; Mayo, Kevin H.; Thijssen, Victor L.J.L.; Griffioen, Arjan W.

2005-01-01

Anginex, a designed peptide 33-mer, is a potent angiogenesis inhibitor and anti-tumor agent in vivo. Anginex functions by inhibiting endothelial cell (EC) proliferation and migration leading to detachment and apoptosis of activated EC's. To better understand tumor endothelium targeting properties of anginex and enable its use in gene therapy, we constructed an artificial gene encoding the biologically exogenous peptide and produced the protein recombinantly in Pichia pastoris. Mass spectrometry shows recombinant anginex to be a dimer and circular dichroism shows the recombinant protein folds with β-strand structure like the synthetic peptide. Moreover, like parent anginex, the recombinant protein is active at inhibiting EC growth and migration, as well as inhibiting angiogenesis in vivo in the chorioallantoic membrane of the chick embryo. This study demonstrated that it is possible to produce a functionally active protein version of a rationally designed peptide, using an artificial gene and the recombinant protein approach

Higher accumulation of F1-V fusion recombinant protein in plants after induction of protein body formation.

Science.gov (United States)

Alvarez, M Lucrecia; Topal, Emel; Martin, Federico; Cardineau, Guy A

2010-01-01

Improving foreign protein accumulation is crucial for enhancing the commercial success of plant-based production systems since product yields have a major influence on process economics. Cereal grain evolved to store large amounts of proteins in tightly organized aggregates. In maize, gamma-Zein is the major storage protein synthesized by the rough endoplasmic reticulum (ER) and stored in specialized organelles called protein bodies (PB). Zera (gamma-Zein ER-accumulating domain) is the N-terminal proline-rich domain of gamma-zein that is sufficient to induce the assembly of PB formation. Fusion of the Zera domain to proteins of interest results in assembly of dense PB-like, ER-derived organelles, containing high concentration of recombinant protein. Our main goal was to increase recombinant protein accumulation in plants in order to enhance the efficiency of orally-delivered plant-made vaccines. It is well known that oral vaccination requires substantially higher doses than parental formulations. As a part of a project to develop a plant-made plague vaccine, we expressed our model antigen, the Yersinia pestis F1-V antigen fusion protein, with and without a fused Zera domain. We demonstrated that Zera-F1-V protein accumulation was at least 3x higher than F1-V alone when expressed in three different host plant systems: Ncotiana benthamiana, Medicago sativa (alfalfa) and Nicotiana tabacum NT1 cells. We confirmed the feasibility of using Zera technology to induce protein body formation in non-seed tissues. Zera expression and accumulation did not affect plant development and growth. These results confirmed the potential exploitation of Zera technology to substantially increase the accumulation of value-added proteins in plants.

Companion Protease Inhibitors for the In Situ Protection of Recombinant Proteins in Plants.

Science.gov (United States)

Robert, Stéphanie; Jutras, Philippe V; Khalf, Moustafa; D'Aoust, Marc-André; Goulet, Marie-Claire; Sainsbury, Frank; Michaud, Dominique

2016-01-01

We previously described a procedure for the use of plant protease inhibitors as "companion" accessory proteins to prevent unwanted proteolysis of clinically useful recombinant proteins in leaf crude protein extracts (Benchabane et al. Methods Mol Biol 483:265-273, 2009). Here we describe the use of these inhibitors for the protection of recombinant proteins in planta, before their extraction from leaf tissues. A procedure is first described involving inhibitors co-expressed along-and co-migrating-with the protein of interest in host plant cells. An alternative, single transgene scheme is then described involving translational fusions of the recombinant protein and companion inhibitor. These approaches may allow for a significant improvement of protein steady-state levels in leaves, comparable to yield improvements observed with protease-deficient strains of less complex protein expression hosts such as E. coli or yeasts.

Characterization of mini-protein S, a recombinant variant of protein S that lacks the sex hormone binding globulin-like domain

NARCIS (Netherlands)

van Wijnen, M.; Stam, J. G.; Chang, G. T.; Meijers, J. C.; Reitsma, P. H.; Bertina, R. M.; Bouma, B. N.

1998-01-01

Protein S is a vitamin K-dependent glycoprotein involved in the regulation of the anticoagulant activity of activated protein C (APC). Also, an anticoagulant role for protein S, independent of APC, has been described. Protein S has a unique C-terminal sex hormone binding globulin (SHBG)-like domain

An inducible expression system for high-level expression of recombinant proteins in slow growing mycobacteria.

Science.gov (United States)

Leotta, Lisa; Spratt, Joanne M; Kong, Carlyn U; Triccas, James A

2015-09-01

A novel protein expression vector utilising the inducible hspX promoter of Mycobacterium tuberculosis was constructed and evaluated in this study. High-level induction of three mycobacterial antigens, comprising up to 9% of bacterial sonicate, was demonstrated in recombinant Mycobacterium bovis BCG when grown under low-oxygen tension, which serves to enhance hspX promoter activity. Recombinant proteins were efficiently purified from bacterial lysates in a soluble form by virtue of a C-terminal 6-histidine tag. Purification of the immunodominant M. tuberculosis Ag85B antigen using this system resulted in a recombinant protein that stimulated significant IFN-γ release from Ag85B-reactive T cells generated after vaccination of mice with an Ag85B-expressing vaccine. Further, the M. tuberculosis L-alanine dehydrogenase (Ald) protein purified from recombinant BCG displayed strong enzymatic activity in recombinant form. This study demonstrated that high levels of native-like recombinant mycobacterial proteins can be produced in mycobacterial hosts, and this may aid the analysis of mycobacterial protein function and the development of new treatments. Copyright © 2015 Elsevier B.V. All rights reserved.

Purification, crystallization and preliminary X-ray diffraction of human S100A15

Energy Technology Data Exchange (ETDEWEB)

Boeshans, Karen M. [X-ray Crystallography Facility, NIAMS, National Institutes of Health, Bethesda, MD 20892 (United States); Wolf, Ronald; Voscopoulos, Christopher [Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Gillette, William; Esposito, Dominic [Protein Expression Laboratory, Research Technology Program, National Cancer Institute, SAIC-Frederick Inc., Frederick, MD 21702 (United States); Mueser, Timothy C. [Department of Chemistry, University of Toledo, Toledo, OH 43606 (United States); Yuspa, Stuart H. [Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Ahvazi, Bijan, E-mail: ahvazib@mail.nih.gov [X-ray Crystallography Facility, NIAMS, National Institutes of Health, Bethesda, MD 20892 (United States)

2006-05-01

S100 proteins are differentially expressed during epithelial cell maturation, tumorigenesis and inflammation. The novel human S100A15 protein has been cloned, expressed, purified and crystallized in two crystal forms, a triclinic and a monoclinic form, which diffract to 1.7 and 2.0 Å, respectively. Human S100A15 is a novel member of the S100 family of EF-hand calcium-binding proteins and was recently identified in psoriasis, where it is significantly upregulated in lesional skin. The protein is implicated as an effector in calcium-mediated signal transduction pathways. Although its biological function is unclear, the association of the 11.2 kDa S100A15 with psoriasis suggests that it contributes to the pathogenesis of the disease and could provide a molecular target for therapy. To provide insight into the function of S100A15, the protein was crystallized to visualize its structure and to further the understanding of how the many similar calcium-binding mediator proteins in the cell distinguish their cognate target molecules. The S100A15 protein has been cloned, expressed and purified to homogeneity and produced two crystal forms. Crystals of form I are triclinic, with unit-cell parameters a = 33.5, b = 44.3, c = 44.8 Å, α = 71.2, β = 68.1, γ = 67.8° and an estimated two molecules in the asymmetric unit, and diffract to 1.7 Å resolution. Crystals of form II are monoclinic, with unit-cell parameters a = 82.1, b = 33.6, c = 52.2 Å, β = 128.2° and an estimated one molecule in the asymmetric unit, and diffract to 2.0 Å resolution. This structural analysis of the human S100A15 will further aid in the phylogenic comparison between the other members of the S100 protein family, especially the highly homologous paralog S100A7.

Generation of monoclonal antibodies for the assessment of protein purification by recombinant ribosomal coupling

DEFF Research Database (Denmark)

Kristensen, Janni; Sperling-Petersen, Hans Uffe; Mortensen, Kim Kusk

2005-01-01

We recently described a conceptually novel method for the purification of recombinant proteins with a propensity to form inclusion bodies in the cytoplasm of Escherichia coli. Recombinant proteins were covalently coupled to the E. coli ribosome by fusing them to ribosomal protein 23 (rpL23...... therefore purified rpL23-GFP-His, rpL23-His and GFP from E. coli recombinants using affinity, ion exchange and hydrophobic interaction chromatography. These proteins could be purified with yields of 150, 150 and 1500 microg per gram cellular wet weight, respectively. However, rpL23-GFP-His could only...... proteolytic cleavage sites. We conclude that the generated antibodies can be used to evaluate ribosomal coupling of recombinant target proteins as well as the efficiency of their separation from the ribosome....

Homologous recombination in mammalian cells: effect of p53 and Bcl-2 proteins, replication inhibition and ionizing radiations

International Nuclear Information System (INIS)

Saintigny, Yannick

1999-01-01

The control of cell cycle, associated with the mechanisms of replication, DNA repair/recombination allows the cells to maintain their genetic integrity. The p53 protein ensures the control of G1/S transition. Its inactivation would allow to initial replication on damaged matrix and lead to the block of replication forks followed by DNA strand breaks, good substrates for recombination. This work shows that the expression of mutant p53 protein stimulates both spontaneous and radio-induced homologous recombination, independently of the control of cell cycle. Moreover, the use of a set of replication inhibitors show that inhibition of the replication elongation stimulates recombination more strongly than the initiation inhibition. Replication arrest by these inhibitors also significantly increases the number of DNA strand breaks. These results highlighted a point of action of p53 protein on the ultimate stages of the homologous recombination mechanism. Lastly, the expression of Bcl-2 protein inhibits apoptosis and increases survival, but specifically inhibits conservative recombination, after radiation as well as in absence of apoptotic stress. The extinction of this mechanism of DNA repair is associated with an increase of mutagenesis. Taken together, these results allow ta consider the maintenance of the genetic stability as a cellular network involving different pathways. A multiple stages model for tumoral progression can be deduced. (author) [fr

Effective delivery of recombinant proteins to rod photoreceptors via lipid nanovesicles

Energy Technology Data Exchange (ETDEWEB)

Asteriti, Sabrina [Dept. of Translational Research, University of Pisa, Pisa (Italy); Dal Cortivo, Giuditta [Dept. of Life Sciences and Reproduction, University of Verona, Strada Le Grazie 8, Verona (Italy); Pontelli, Valeria [Dept. of Neurological and Movement Sciences, University of Verona, Strada Le Grazie 8, Verona (Italy); Cangiano, Lorenzo [Dept. of Translational Research, University of Pisa, Pisa (Italy); Buffelli, Mario, E-mail: mario.buffelli@univr.it [Dept. of Neurological and Movement Sciences, University of Verona, Strada Le Grazie 8, Verona (Italy); Center for Biomedical Computing, University of Verona, Strada le Grazie 8, 37134 Verona (Italy); Dell’Orco, Daniele, E-mail: daniele.dellorco@univr.it [Dept. of Life Sciences and Reproduction, University of Verona, Strada Le Grazie 8, Verona (Italy); Center for Biomedical Computing, University of Verona, Strada le Grazie 8, 37134 Verona (Italy)

2015-06-12

The potential of liposomes to deliver functional proteins in retinal photoreceptors and modulate their physiological response was investigated by two experimental approaches. First, we treated isolated mouse retinas with liposomes encapsulating either recoverin, an important endogenous protein operating in visual phototransduction, or antibodies against recoverin. We then intravitrally injected in vivo liposomes encapsulating either rhodamin B or recoverin and we investigated the distribution in retina sections by confocal microscopy. The content of liposomes was found to be released in higher amount in the photoreceptor layer than in the other regions of the retina and the functional effects of the release were in line with the current model of phototransduction. Our study sets the basis for quantitative investigations aimed at assessing the potential of intraocular protein delivery via biocompatible nanovesicles, with promising implications for the treatment of retinal diseases affecting the photoreceptor layer. - Highlights: • Recombinant proteins encapsulated in nano-sized liposomes injected intravitreally reach retinal photoreceptors. • The phototransduction cascade in rods is modulated by the liposome content. • Mathematical modeling predicts the alteration of the photoresponses following liposome fusion.

Alarmins S100A8 and S100A9 elicit a catabolic effect in human osteoarthritic chondrocytes that is dependent on Toll-like receptor 4.

NARCIS (Netherlands)

Schelbergen, R.F.P.; Blom, A.B.; Bosch, M.H.J. van den; Sloetjes, A.W.; Abdollahi-Roodsaz, S.; Schreurs, B.W.; Mort, J.S.; Vogl, T.; Roth, J.; Berg, W.B. van den; Lent, P.L.E.M. van

2012-01-01

OBJECTIVE: S100A8 and S100A9 are two Ca(2+) binding proteins classified as damage-associated molecular patterns or alarmins that are found in high amounts in the synovial fluid of osteoarthritis (OA) patients. The purpose of this study was to investigate whether S100A8 and/or S100A9 can interact

Generation of Nanobodies against SlyD and development of tools to eliminate this bacterial contaminant from recombinant proteins.

Science.gov (United States)

Hu, Yaozhong; Romão, Ema; Vertommen, Didier; Vincke, Cécile; Morales-Yánez, Francisco; Gutiérrez, Carlos; Liu, Changxiao; Muyldermans, Serge

2017-09-01

The gene for a protein domain, derived from a tumor marker, fused to His tag codons and under control of a T7 promotor was expressed in E. coli strain BL21 (DE3). The recombinant protein was purified from cell lysates through immobilized metal affinity chromatography and size-exclusion chromatography. A contaminating bacterial protein was consistently co-purified, even using stringent washing solutions containing 50 or 100 mM imidazole. Immunization of a dromedary with this contaminated protein preparation, and the subsequent generation and panning of the immune Nanobody library yielded several Nanobodies of which 2/3 were directed against the bacterial contaminant, reflecting the immunodominance of this protein to steer the dromedary immune response. Affinity adsorption of this contaminant using one of our specific Nanobodies followed by mass spectrometry identified the bacterial contaminant as FKBP-type peptidyl-prolyl cis-trans isomerase (SlyD) from E. coli. This SlyD protein contains in its C-terminal region 14 histidines in a stretch of 31 amino acids, which explains its co-purification on Ni-NTA resin. This protein is most likely present to varying extents in all recombinant protein preparations after immobilized metal affinity chromatography. Using our SlyD-specific Nb 5 we generated an immune-complex that could be removed either by immunocapturing or by size exclusion chromatography. Both methods allow us to prepare a recombinant protein sample where the SlyD contaminant was quantitatively eliminated. Copyright © 2017 Elsevier Inc. All rights reserved.

Membrane interactions of S100A12 (Calgranulin C.

Directory of Open Access Journals (Sweden)

Assuero F Garcia

Full Text Available S100A12 (Calgranulin C is a small acidic calcium-binding peripheral membrane protein with two EF-hand structural motifs. It is expressed in macrophages and lymphocytes and highly up-regulated in several human inflammatory diseases. In pigs, S100A12 is abundant in the cytosol of granulocytes, where it is believed to be involved in signal modulation of inflammatory process. In this study, we investigated the interaction of the porcine S100A12 with phospholipid bilayers and the effect that ions (Ca(2+, Zn(2+ or both together have in modifying protein-lipid interactions. More specifically, we intended to address issues such as: (1 is the protein-membrane interaction modulated by the presence of ions? (2 is the protein overall structure affected by the presence of the ions and membrane models simultaneously? (3 what are the specific conformational changes taking place when ions and membranes are both present? (4 does the protein have any kind of molecular preferences for a specific lipid component? To provide insight into membrane interactions and answer those questions, synchrotron radiation circular dichroism spectroscopy, fluorescence spectroscopy, and surface plasmon resonance were used. The use of these combined techniques demonstrated that this protein was capable of interacting both with lipids and with ions in solution, and enabled examination of changes that occur at different levels of structure organization. The presence of both Ca(2+ and Zn(2+ ions modify the binding, conformation and thermal stability of the protein in the presence of lipids. Hence, these studies examining molecular interactions of porcine S100A12 in solution complement the previously determined crystal structure information on this family of proteins, enhancing our understanding of its dynamics of interaction with membranes.

The synthesis of recombinant membrane proteins in yeast for structural studies.

Science.gov (United States)

Routledge, Sarah J; Mikaliunaite, Lina; Patel, Anjana; Clare, Michelle; Cartwright, Stephanie P; Bawa, Zharain; Wilks, Martin D B; Low, Floren; Hardy, David; Rothnie, Alice J; Bill, Roslyn M

2016-02-15

Historically, recombinant membrane protein production has been a major challenge meaning that many fewer membrane protein structures have been published than those of soluble proteins. However, there has been a recent, almost exponential increase in the number of membrane protein structures being deposited in the Protein Data Bank. This suggests that empirical methods are now available that can ensure the required protein supply for these difficult targets. This review focuses on methods that are available for protein production in yeast, which is an important source of recombinant eukaryotic membrane proteins. We provide an overview of approaches to optimize the expression plasmid, host cell and culture conditions, as well as the extraction and purification of functional protein for crystallization trials in preparation for structural studies. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

[Evaluation of the Recombinant Protein Tp0965 of Treponema Pallidum as Perspective Antigen for the Improved Serological Diagnosis of Syphilis].

Science.gov (United States)

Runina, A V; Starovoitova, A S; Deryabin, D G; Kubanov, A A

2016-01-01

BACKGRAUND. Treponemal tests based on the detection of antibodies against the Treponema pallidum antigens are the most specific methods for serological diagnosis of syphilis. Due to the inability to cultivate this bacterium in vitro, the most promising sources of antigens for diagnostics are recombinant proteins of T. pallidum. Evaluation of the analytical value of certain T. pallidum proteins is the approach to improve sensitivity, specificity, and reproducibility of syphilis serological tests, including possibilities of differential diagnosis of various forms of the disease. The aim of the research was to evaluate the analytical values (sensitivity and specificity) of recombinant protein Tp0965 of T. pallidum as a candidate antigen for serological diagnosis of syphilis. tp0965 gene was cloned into the expression vector pET28a and the construct was used for the transformation of E. coli BL-21 (DE3) cells and further expression and purification of the recombinant protein. The collected protein was used as T. pallidum antigen for serum analysis (ELISA) of groups of patients with various forms of syphilis (n=84) and the group of healthy donors (n = 25). High frequency of positive ELISA results was shown with serum of patients with syphilis, compared to the group of healthy donors. The sensitivity of serological reactions using recombinant protein Tp0965 was 98.8%, specificity--87.5%. The highest sensitivity (100%) was detected in the groups of patients with primary, secondary and early latent syphilis while in the group of patients with late latent syphilis it decreased to 95.2%. We concluded that due to its specificity T. pallidum recombinant protein Tp0965 can be used as a novel perspective antigen for development of syphilis serological diagnostic assays (for primary and early latent forms).

Importance of Heat and Pressure for Solubilization of Recombinant Spider Silk Proteins in Aqueous Solution.

Science.gov (United States)

Jones, Justin A; Harris, Thomas I; Oliveira, Paula F; Bell, Brianne E; Alhabib, Abdulrahman; Lewis, Randolph V

2016-11-23

The production of recombinant spider silk proteins continues to be a key area of interest for a number of research groups. Several key obstacles exist in their production as well as in their formulation into useable products. The original reported method to solubilize recombinant spider silk proteins (rSSp) in an aqueous solution involved using microwaves to quickly generate heat and pressure inside of a sealed vial containing rSSp and water. Fibers produced from this system are remarkable in their mechanical ability and demonstrate the ability to be stretched and recover 100 times. The microwave method dissolves the rSSPs with dissolution time increasing with higher molecular weight constructs, increasing concentration of rSSPs, protein type, and salt concentration. It has proven successful in solvating a number of different rSSPs including native-like sequences (MaSp1, MaSp2, piriform, and aggregate) as well as chimeric sequences (FlAS) in varied concentrations that have been spun into fibers and formed into films, foams, sponges, gels, coatings, macro and micro spheres and adhesives. The system is effective but inherently unpredictable and difficult to control. Provided that the materials that can be generated from this method of dissolution are impressive, an alternative means of applying heat and pressure that is controllable and predictable has been developed. Results indicate that there are combinations of heat and pressure (135 °C and 140 psi) that result in maximal dissolution without degrading the recombinant MaSp2 protein tested, and that heat and pressure are the key elements to the method of dissolution.

Genome-scale metabolic model of Pichia pastoris with native and humanized glycosylation of recombinant proteins.

Science.gov (United States)

Irani, Zahra Azimzadeh; Kerkhoven, Eduard J; Shojaosadati, Seyed Abbas; Nielsen, Jens

2016-05-01

Pichia pastoris is used for commercial production of human therapeutic proteins, and genome-scale models of P. pastoris metabolism have been generated in the past to study the metabolism and associated protein production by this yeast. A major challenge with clinical usage of recombinant proteins produced by P. pastoris is the difference in N-glycosylation of proteins produced by humans and this yeast. However, through metabolic engineering, a P. pastoris strain capable of producing humanized N-glycosylated proteins was constructed. The current genome-scale models of P. pastoris do not address native nor humanized N-glycosylation, and we therefore developed ihGlycopastoris, an extension to the iLC915 model with both native and humanized N-glycosylation for recombinant protein production, but also an estimation of N-glycosylation of P. pastoris native proteins. This new model gives a better prediction of protein yield, demonstrates the effect of the different types of N-glycosylation of protein yield, and can be used to predict potential targets for strain improvement. The model represents a step towards a more complete description of protein production in P. pastoris, which is required for using these models to understand and optimize protein production processes. © 2015 Wiley Periodicals, Inc.

[Analysis of the mRNA expression of the S100β protein in adipocytes of patients with diabetes mellitus, type 2].

Science.gov (United States)

Hamasaki, Mike Yoshio; Hirata, Mario Hiroyuki; Hirata, Rosario Dominguez Crespo; Himelfarb, Silvia Tchernin; Campos, Leila Maria Guissoni; Nogueira, Maria Inês

2012-10-01

This study aims to explore the possible relationship between the expression level of S100β protein mRNA with diabetes mellitus type 2 in adipocytes from patients with this disease in comparison with normoglycemic individuals. Samples of adipose tissue of eight patients from the coronary section of the Institute Dante Pazzanese of Cardiology (IDPC), four in Group Diabetes and four of Normoglycemic group, were evaluated by RT-PCR real time. An increase around 15 times values, between the threshold cycle (ΔCt), of mRNA expression of S100β protein in adipocytes of the diabetes group was observed in comparison to the control group (p = 0.015). Our results indicate, for the first time, that there is coexistence of increased expression of the S100β and the type 2 diabetes mellitus gene.

Immunogenicity of recombinant feline infectious peritonitis virus spike protein in mice and kittens

NARCIS (Netherlands)

Horzinek, M.C.; Vennema, H.; Groot, R. de; Harbour, D.A.; Dalderup, M.; Gruffydd-Jones, T.; Spaan, W.J.M.

1990-01-01

The gene encoding the fusogenic spike protein of the coronavirus causing feline infectious peritonitis (FIVP) was recombined into the genome of vaccinia virus, strain WR. The recombinant induced spike protein specific, in vitro neutralizing antibodies in mkice. When kittens were immunized with the

The effect of alcohol on recombinant proteins derived from mammalian adenylyl cyclase

Directory of Open Access Journals (Sweden)

Emily Qualls-Creekmore

2017-07-01

Full Text Available The cyclic AMP (cAMP signaling pathway is implicated in the development of alcohol use disorder. Previous studies have demonstrated that ethanol enhances the activity of adenylyl cyclase (AC in an isoform specific manner; AC7 is most enhanced by ethanol, and regions responsible for enhancement by ethanol are located in the cytoplasmic domains of the AC7 protein. We hypothesize that ethanol modulates AC activity by directly interacting with the protein and that ethanol effects on AC can be studied using recombinant AC in vitro. AC recombinant proteins containing only the C1a or C2 domains of AC7 and AC9 individually were expressed in bacteria, and purified. The purified recombinant AC proteins retained enzymatic activity and isoform specific alcohol responsiveness. The combination of the C1a or C2 domains of AC7 maintained the same alcohol cutoff point as full-length AC7. We also find that the recombinant AC7 responds to alcohol differently in the presence of different combinations of activators including MnCl2, forskolin, and Gsα. Through a series of concentration-response experiments and curve fitting, the values for maximum activities, Hill coefficients, and EC50 were determined in the absence and presence of butanol as a surrogate of ethanol. The results suggest that alcohol modulates AC activity by directly interacting with the AC protein and that the alcohol interaction with the AC protein occurs at multiple sites with positive cooperativity. This study indicates that the recombinant AC proteins expressed in bacteria can provide a useful model system to investigate the mechanism of alcohol action on their activity.

Overview of the recombinant proteins purification by affinity tags and ...

African Journals Online (AJOL)

From protein within isolation process which the same matter increases labor costs further and prevents application of these tags in industrial scale. Therefore proper replacement is emphasized for enzymatic removal of purification tags. Keywords: protein purification; recombinant proteins; self-cleavable tags; Intein tags; ...

Osteoinductive recombinant silk fusion proteins for bone regeneration.

Science.gov (United States)

Dinjaski, Nina; Plowright, Robyn; Zhou, Shun; Belton, David J; Perry, Carole C; Kaplan, David L

2017-02-01

Protein polymers provide a unique opportunity for tunable designs of material systems due to the genetic basis of sequence control. To address the challenge of biomineralization interfaces with protein based materials, we genetically engineered spider silks to design organic-inorganic hybrid systems. The spider silk inspired domain (SGRGGLGGQG AGAAAAAGGA GQGGYGGLGSQGT) 15 served as an organic scaffold to control material stability and to allow multiple modes of processing, whereas the hydroxyapatite binding domain VTKHLNQISQSY (VTK), provided control over osteogenesis. The VTK domain was fused either to the N-, C- or both terminals of the spider silk domain to understand the effect of position on material properties and mineralization. The addition of the VTK domain to silk did not affect the physical properties of the silk recombinant constructs, but it had a critical role in the induction of biomineralization. When the VTK domain was placed on both the C- and N-termini the formation of crystalline hydroxyapatite was significantly increased. In addition, all of the recombinant proteins in film format supported the growth and proliferation of human mesenchymal stem cells (hMSCs). Importantly, the presence of the VTK domain enhanced osteoinductive properties up to 3-fold compared to the control (silk alone without VTK). Therefore, silk-VTK fusion proteins have been shown suitable for mineralization and functionalization for specific biomedical applications. Organic-inorganic interfaces are integral to biomaterial functions in many areas of repair and regeneration. Several protein polymers have been investigated for this purpose. Despite their success the limited options to fine-tune their material properties, degradation patterns and functionalize them for each specific biomedical application limits their application. Various studies have shown that the biological performance of such proteins can be improved by genetic engineering. The present study provides data

S-layer architectures : extending the morphogenetic potential of S-layer protein self-assembly

International Nuclear Information System (INIS)

Schuster, D.

2013-01-01

Self-assembly of molecular building blocks is a common principle for bottom up based building principles in nature. One example are crystalline bacterial surface layers, termed S-layers, which are the most commonly observed cell surface structures in prokaryotic organisms. They recrystallize into highly ordered, porous protein meshworks with unit cell sizes of 3 to 30 nm and pore sizes of 2 to 8 nm. In this work, S-layers were self-assembled on various three dimensional scaffolds in order to fabricate novel S-layer architectures. Exploiting the stabilizing effect of silica deposited on the S-layer protein meshwork led to the construction of hollow S-layer nano-containers derived from coated liposomes. Transmission electron microscopy (TEM) techniques and release experiments with fluorescent dyes confirmed the dissolution of the supporting lipids. Silica deposition on different spherical particles in solution, as well as on planar S-layer coated surfaces, could be monitored by measuring the ζ-potential, the decline of monosilicic acid in solution, by using scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis or by quartz crystal microbalance with dissipation monitoring (QCM-D). Both, ζ-potential and release experiments showed differences between silicified plain liposomes and silicified S-layer coated liposomes. In addition, nanocapsules with calcium carbonate cores served as another template for the construction of silica supported S-layer architectures. These were investigated by SEM and fluorescence microscopy after fluorescence labeling. Additional coating with polyelectrolytes increased the stability of the nanocapsules. Their mechanical properties were characterized by atomic force microscopy (AFM). The influence of silica deposition was investigated by AFM and SEM. Further on, emulsomes and gas filled lipid supported microbubbles may serve as other templates for the design of spherical protein constructs although extraction of the

Evaluation of the Potency, Neutralizing Antibody Response, and Stability of a Recombinant Fusion Protein Vaccine for Streptococcus pyogenes.

Science.gov (United States)

Burlet, E; HogenEsch, H; Dunham, A; Morefield, G

2017-05-01

Streptococcus pyogenes or group A streptococcus (GAS) is a Gram-positive bacterium that can cause a wide range of diseases, including pharyngitis, impetigo, scarlet fever, necrotizing fasciitis, rheumatic fever, and streptococcal toxic shock syndrome. Despite the increasing burden on global health caused by GAS, there is currently no licensed vaccine available. In this study, we evaluated immunogenicity, induction of neutralizing antibodies, and stability of a new recombinant fusion protein vaccine that targets infections from GAS. The recombinant fusion protein (SpeAB) combines inactive mutant forms of streptococcal pyrogenic exotoxin A (SpeA) and streptococcal pyrogenic exotoxin B (SpeB). The SpeAB vaccine evaluated in this study was adsorbed to an aluminum adjuvant and demonstrated robust immunogenicity, eliciting production of specific neutralizing antibodies against SpeA and SpeB, two major virulence factors of S. pyogenes. Stability studies suggest that the vaccine will retain immunogenicity for at least 2 years when stored at refrigerated temperatures. This novel vaccine shows great potential to provide protection against GAS infections and to reduce the burden of GAS disease globally.

Bacterial-based systems for expression and purification of recombinant Lassa virus proteins of immunological relevance

Directory of Open Access Journals (Sweden)

Cashman Kathleen A

2008-06-01

Full Text Available Abstract Background There is a significant requirement for the development and acquisition of reagents that will facilitate effective diagnosis, treatment, and prevention of Lassa fever. In this regard, recombinant Lassa virus (LASV proteins may serve as valuable tools in diverse antiviral applications. Bacterial-based systems were engineered for expression and purification of recombinant LASV nucleoprotein (NP, glycoprotein 1 (GP1, and glycoprotein 2 (GP2. Results Full-length NP and the ectodomains of GP1 and GP2 were generated as maltose-binding protein (MBP fusions in the Rosetta strains of Escherichia coli (E. coli using pMAL-c2x vectors. Average fusion protein yields per liter of culture for MBP-NP, MBP-GP1, and MBP-GP2 were 10 mg, 9 mg, and 9 mg, respectively. Each protein was captured from cell lysates using amylose resin, cleaved with Factor Xa, and purified using size-exclusion chromatography (SEC. Fermentation cultures resulted in average yields per liter of 1.6 mg, 1.5 mg, and 0.7 mg of purified NP, GP1 and GP2, respectively. LASV-specific antibodies in human convalescent sera specifically detected each of the purified recombinant LASV proteins, highlighting their utility in diagnostic applications. In addition, mouse hyperimmune ascitic fluids (MHAF against a panel of Old and New World arenaviruses demonstrated selective cross reactivity with LASV proteins in Western blot and enzyme-linked immunosorbent assay (ELISA. Conclusion These results demonstrate the potential for developing broadly reactive immunological assays that employ all three arenaviral proteins individually and in combination.

Refolding techniques for recovering biologically active recombinant proteins from inclusion bodies.

Science.gov (United States)

Yamaguchi, Hiroshi; Miyazaki, Masaya

2014-02-20

Biologically active proteins are useful for studying the biological functions of genes and for the development of therapeutic drugs and biomaterials in a biotechnology industry. Overexpression of recombinant proteins in bacteria, such as Escherichia coli, often results in the formation of inclusion bodies, which are protein aggregates with non-native conformations. As inclusion bodies contain relatively pure and intact proteins, protein refolding is an important process to obtain active recombinant proteins from inclusion bodies. However, conventional refolding methods, such as dialysis and dilution, are time consuming and, often, recovered yields of active proteins are low, and a trial-and-error process is required to achieve success. Recently, several approaches have been reported to refold these aggregated proteins into an active form. The strategies largely aim at reducing protein aggregation during the refolding procedure. This review focuses on protein refolding techniques using chemical additives and laminar flow in microfluidic chips for the efficient recovery of active proteins from inclusion bodies.

Refolding Techniques for Recovering Biologically Active Recombinant Proteins from Inclusion Bodies

Directory of Open Access Journals (Sweden)

Hiroshi Yamaguchi

2014-02-01

Full Text Available Biologically active proteins are useful for studying the biological functions of genes and for the development of therapeutic drugs and biomaterials in a biotechnology industry. Overexpression of recombinant proteins in bacteria, such as Escherichia coli, often results in the formation of inclusion bodies, which are protein aggregates with non-native conformations. As inclusion bodies contain relatively pure and intact proteins, protein refolding is an important process to obtain active recombinant proteins from inclusion bodies. However, conventional refolding methods, such as dialysis and dilution, are time consuming and, often, recovered yields of active proteins are low, and a trial-and-error process is required to achieve success. Recently, several approaches have been reported to refold these aggregated proteins into an active form. The strategies largely aim at reducing protein aggregation during the refolding procedure. This review focuses on protein refolding techniques using chemical additives and laminar flow in microfluidic chips for the efficient recovery of active proteins from inclusion bodies.

Co-administration of recombinant major envelope proteins (rA27L and rH3L) of buffalopox virus provides enhanced immunogenicity and protective efficacy in animal models.

Science.gov (United States)

Kumar, Amit; Yogisharadhya, Revanaiah; Venkatesan, Gnanavel; Bhanuprakash, Veerakyathappa; Pandey, Awadh Bihari; Shivachandra, Sathish Bhadravati

2017-05-01

Buffalopox virus (BPXV) and other vaccinia-like viruses (VLVs) are causing an emerging/re-emerging zoonosis affecting buffaloes, cattle and humans in India and other countries. A27L and H3L are immuno-dominant major envelope proteins of intracellular mature virion (IMV) of orthopoxviruses (OPVs) and are highly conserved with an ability to elicit neutralizing antibodies. In the present study, two recombinant proteins namely; rA27L ( 21 S to E 110 ; ∼30 kDa) and rH3L( 1 M to I 280 ; ∼50 kDa) of BPXV-Vij/96 produced from Escherichia coli were used in vaccine formulation. A combined recombinant subunit vaccine comprising rA27L and rH3L antigens (10 μg of each) was used for active immunization of adult mice (20μg/dose/mice) with or without adjuvant (FCA/FIA) by intramuscular route. Immune responses revealed a gradual increase in antigen specific serum IgG as well as neutralizing antibody titers measured by using indirect-ELISA and serum neutralization test (SNT) respectively, which were higher as compared to that elicited by individual antigens. Suckling mice passively administered with combined anti-A27L and anti-H3L sera showed a complete (100%) pre-exposure protection upon challenge with virulent BPXV. Conclusively, this study highlights the potential utility of rA27L and rH3L proteins as safer candidate prophylactic antigens in combined recombinant subunit vaccine for buffalopox as well as passive protective efficacy of combined sera in employing better pre-exposure protection against virulent BPXV. Copyright © 2017 Elsevier B.V. All rights reserved.

Mutations in the RNA-binding domains of tombusvirus replicase proteins affect RNA recombination in vivo

International Nuclear Information System (INIS)

Panaviene, Zivile; Nagy, Peter D.

2003-01-01

RNA recombination, which is thought to occur due to replicase errors during viral replication, is one of the major driving forces of virus evolution. In this article, we show evidence that the replicase proteins of Cucumber necrosis virus, a tombusvirus, are directly involved in RNA recombination in vivo. Mutations within the RNA-binding domains of the replicase proteins affected the frequency of recombination observed with a prototypical defective-interfering (DI) RNA, a model template for recombination studies. Five of the 17 replicase mutants tested showed delay in the formation of recombinants when compared to the wild-type helper virus. Interestingly, two replicase mutants accelerated recombinant formation and, in addition, these mutants also increased the level of subgenomic RNA synthesis (Virology 308 (2003), 191-205). A trans-complementation system was used to demonstrate that mutation in the p33 replicase protein resulted in altered recombination rate. Isolated recombinants were mostly imprecise (nonhomologous), with the recombination sites clustered around a replication enhancer region and a putative cis-acting element, respectively. These RNA elements might facilitate the proposed template switching events by the tombusvirus replicase. Together with data in the article cited above, results presented here firmly establish that the conserved RNA-binding motif of the replicase proteins is involved in RNA replication, subgenomic RNA synthesis, and RNA recombination

Immunogenicity of Recombinant Proteins Consisting of Plasmodium vivax Circumsporozoite Protein Allelic Variant-Derived Epitopes Fused with Salmonella enterica Serovar Typhimurium Flagellin

Science.gov (United States)

Leal, Monica Teixeira Andrade; Camacho, Ariane Guglielmi Ariza; Teixeira, Laís Helena; Bargieri, Daniel Youssef; Soares, Irene Silva; Tararam, Cibele Aparecida

2013-01-01

A Plasmodium falciparum circumsporozoite protein (CSP)-based recombinant fusion vaccine is the first malaria vaccine to reach phase III clinical trials. Resistance to infection correlated with the production of antibodies to the immunodominant central repeat region of the CSP. In contrast to P. falciparum, vaccine development against the CSP of Plasmodium vivax malaria is far behind. Based on this gap in our knowledge, we generated a recombinant chimeric protein containing the immunodominant central repeat regions of the P. vivax CSP fused to Salmonella enterica serovar Typhimurium-derived flagellin (FliC) to activate the innate immune system. The recombinant proteins that were generated contained repeat regions derived from each of the 3 different allelic variants of the P. vivax CSP or a fusion of regions derived from each of the 3 allelic forms. Mice were subcutaneously immunized with the fusion proteins alone or in combination with the Toll-like receptor 3 (TLR-3) agonist poly(I·C), and the anti-CSP serum IgG response was measured. Immunization with a mixture of the 3 recombinant proteins, each containing immunodominant epitopes derived from a single allelic variant, rather than a single recombinant protein carrying a fusion of regions derived from each of 3 allelic forms elicited a stronger immune response. This response was independent of TLR-4 but required TLR-5/MyD88 activation. Antibody titers significantly increased when poly(I·C) was used as an adjuvant with a mixture of the 3 recombinant proteins. These recombinant fusion proteins are novel candidates for the development of an effective malaria vaccine against P. vivax. PMID:23863502

Antibodies to a recombinant glutamate-rich Plasmodium falciparum protein

DEFF Research Database (Denmark)

Hogh, B; Petersen, E; Dziegiel, Morten Hanefeld

1992-01-01

A Plasmodium falciparum antigen gene coding for a 220-kD glutamate-rich protein (GLURP) has been cloned, and the 783 C-terminal amino acids of this protein (GLURP489-1271) have been expressed as a beta-galactosidase fusion protein in Escherichia coli. The encoded 783 amino acid residues contain two...... areas of repeated amino acid sequences. Antibodies against recombinant GLURP489-1271, as well as against a synthetic peptide corresponding to GLURP899-916, and against a synthetic peptide representing the major glutamate rich repeat sequence from the P. falciparum ring erythrocyte surface antigen (Pf155...... between the anti-GLURP489-1271 and anti-(EENV)6 antibody responses. The data provide indirect evidence for a protective role of antibodies reacting with recombinant GLURP489-1271 as well as with the synthetic peptide (EENV)6 from the Pf155/RESA....

Recombinant VSV G proteins reveal a novel raft-dependent endocytic pathway in resorbing osteoclasts

International Nuclear Information System (INIS)

Mulari, Mika T.K.; Nars, Martin; Laitala-Leinonen, Tiina; Kaisto, Tuula; Metsikkoe, Kalervo; Sun Yi; Vaeaenaenen, H. Kalervo

2008-01-01

Transcytotic membrane flow delivers degraded bone fragments from the ruffled border to the functional secretory domain, FSD, in bone resorbing osteoclasts. Here we show that there is also a FSD-to-ruffled border trafficking pathway that compensates for the membrane loss during the matrix uptake process and that rafts are essential for this ruffled border-targeted endosomal pathway. Replacing the cytoplasmic tail of the vesicular stomatitis virus G protein with that of CD4 resulted in partial insolubility in Triton X-100 and retargeting from the peripheral non-bone facing plasma membrane to the FSD. Recombinant G proteins were subsequently endosytosed and delivered from the FSD to the peripheral fusion zone of the ruffled border, which were both rich in lipid rafts as suggested by viral protein transport analysis and visualizing the rafts with fluorescent recombinant cholera toxin. Cholesterol depletion by methyl-β-cyclodextrin impaired the ruffled border-targeted vesicle trafficking pathway and inhibited bone resorption dose-dependently as quantified by measuring the CTX and TRACP 5b secreted to the culture medium and by measuring the resorbed area visualized with a bi-phasic labeling method using sulpho-NHS-biotin and WGA-lectin. Thus, rafts are vital for membrane recycling from the FSD to the late endosomal/lysosomal ruffled border and bone resorption

Identification of a heterologous cellulase and its N-terminus that can guide recombinant proteins out of Escherichia coli.

Science.gov (United States)

Gao, Dongfang; Wang, Shengjun; Li, Haoran; Yu, Huili; Qi, Qingsheng

2015-04-10

The Gram-negative bacterium Escherichia coli has been widely used as a cell factory for the production of proteins and specialty chemicals because it is the best characterized host with many available expression and regulation systems. However, recombinant proteins produced in Escherichia coli are generally intracellular and often found in the form of inclusion bodies. Extracellular production of proteins is advantageous compared with intracellular production because extracellular proteins can be purified more easily and can avoid protease attack, which results in higher product quality. In this study, we found a catalytic domain of a cellulase (Cel-CD) and its N-terminus can be employed as carriers for extracellular production of recombinant proteins. In this report, we identified the catalytic domain of a cellulase (Cel-CD) from Bacillus sp. that can be secreted into the medium from recombinant E. coli BL21 (DE3) in large quantities without its native signal peptide. By subcellular location analysis, we proved that the secretion was a two-step process and the N-terminal sequence of the full length Cel-CD played a crucial function in secretion. Both the Cel-CD and its N-terminal sequence can serve as carriers for efficient extracellular production of select target proteins. Fusion of heterologous proteins with N20 from Cel-CD can carry the target proteins out of the cells with a concentration from 101 to 691 mg/L in flask cultivation. The extracellular recombinant proteins with a relative high purity. The results suggested that this system has a potential application in plant biomass conversion and industrial production of enzymes and therapeutic proteins.

De novo generation of infectious prions with bacterially expressed recombinant prion protein.

Science.gov (United States)

Zhang, Zhihong; Zhang, Yi; Wang, Fei; Wang, Xinhe; Xu, Yuanyuan; Yang, Huaiyi; Yu, Guohua; Yuan, Chonggang; Ma, Jiyan

2013-12-01

The prion hypothesis is strongly supported by the fact that prion infectivity and the pathogenic conformer of prion protein (PrP) are simultaneously propagated in vitro by the serial protein misfolding cyclic amplification (sPMCA). However, due to sPMCA's enormous amplification power, whether an infectious prion can be formed de novo with bacterially expressed recombinant PrP (rPrP) remains to be satisfactorily resolved. To address this question, we performed unseeded sPMCA with rPrP in a laboratory that has never been exposed to any native prions. Two types of proteinase K (PK)-resistant and self-perpetuating recombinant PrP conformers (rPrP-res) with PK-resistant cores of 17 or 14 kDa were generated. A bioassay revealed that rPrP-res(17kDa) was highly infectious, causing prion disease in wild-type mice with an average survival time of about 172 d. In contrast, rPrP-res(14kDa) completely failed to induce any disease. Our findings reveal that sPMCA is sufficient to initiate various self-perpetuating PK-resistant rPrP conformers, but not all of them possess in vivo infectivity. Moreover, generating an infectious prion in a prion-free environment establishes that an infectious prion can be formed de novo with bacterially expressed rPrP.

Recombinant protein expression in Pichia pastoris strains with an engineered methanol utilization pathway

Science.gov (United States)

2012-01-01

Βackground The methylotrophic yeast Pichia pastoris has become an important host organism for recombinant protein production and is able to use methanol as a sole carbon source. The methanol utilization pathway describes all the catalytic reactions, which happen during methanol metabolism. Despite the importance of certain key enzymes in this pathway, so far very little is known about possible effects of overexpressing either of these key enzymes on the overall energetic behavior, the productivity and the substrate uptake rate in P. pastoris strains. Results A fast and easy-to-do approach based on batch cultivations with methanol pulses was used to characterize different P. pastoris strains. A strain with MutS phenotype was found to be superior over a strain with Mut+ phenotype in both the volumetric productivity and the efficiency in expressing recombinant horseradish peroxidase C1A. Consequently, either of the enzymes dihydroxyacetone synthase, transketolase or formaldehyde dehydrogenase, which play key roles in the methanol utilization pathway, was co-overexpressed in MutS strains harboring either of the reporter enzymes horseradish peroxidase or Candida antarctica lipase B. Although the co-overexpression of these enzymes did not change the stoichiometric yields of the recombinant MutS strains, significant changes in the specific growth rate, the specific substrate uptake rate and the specific productivity were observed. Co-overexpression of dihydroxyacetone synthase yielded a 2- to 3-fold more efficient conversion of the substrate methanol into product, but also resulted in a reduced volumetric productivity. Co-overexpression of formaldehyde dehydrogenase resulted in a 2-fold more efficient conversion of the substrate into product and at least similar volumetric productivities compared to strains without an engineered methanol utilization pathway, and thus turned out to be a valuable strategy to improve recombinant protein production. Conclusions Co

Recombinant protein expression in Pichia pastoris strains with an engineered methanol utilization pathway

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Krainer Florian W

2012-02-01

Full Text Available Abstract Βackground The methylotrophic yeast Pichia pastoris has become an important host organism for recombinant protein production and is able to use methanol as a sole carbon source. The methanol utilization pathway describes all the catalytic reactions, which happen during methanol metabolism. Despite the importance of certain key enzymes in this pathway, so far very little is known about possible effects of overexpressing either of these key enzymes on the overall energetic behavior, the productivity and the substrate uptake rate in P. pastoris strains. Results A fast and easy-to-do approach based on batch cultivations with methanol pulses was used to characterize different P. pastoris strains. A strain with MutS phenotype was found to be superior over a strain with Mut+ phenotype in both the volumetric productivity and the efficiency in expressing recombinant horseradish peroxidase C1A. Consequently, either of the enzymes dihydroxyacetone synthase, transketolase or formaldehyde dehydrogenase, which play key roles in the methanol utilization pathway, was co-overexpressed in MutS strains harboring either of the reporter enzymes horseradish peroxidase or Candida antarctica lipase B. Although the co-overexpression of these enzymes did not change the stoichiometric yields of the recombinant MutS strains, significant changes in the specific growth rate, the specific substrate uptake rate and the specific productivity were observed. Co-overexpression of dihydroxyacetone synthase yielded a 2- to 3-fold more efficient conversion of the substrate methanol into product, but also resulted in a reduced volumetric productivity. Co-overexpression of formaldehyde dehydrogenase resulted in a 2-fold more efficient conversion of the substrate into product and at least similar volumetric productivities compared to strains without an engineered methanol utilization pathway, and thus turned out to be a valuable strategy to improve recombinant protein

Specific Genetic Immunotherapy Induced by Recombinant Vaccine Alpha-Fetoprotein-Heat Shock Protein 70 Complex

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Wang, Xiaoping; Lin, Huanping; Wang, Qiaoxia

Purposes: To construct a recombinant vaccine alpha-fetoprotein (AFP)-heat shock protein (HSP70) complex, and study its ability to induce specific CTL response and its protective effect against AFP-producing tumor. Material/Methods: A recombinant vaccine was constructed by conjugating mouse alpha-fetoprotein to heat shock protein 70. By way of intracutaneous injection, mice were primed and boosted with recombinant vaccine mAFP/HSP70, whereas single mAFP or HSP70 injection as controls. The ELISPOT and ELISA were used to measure the frequency of cells producing the cytokine IFN-γ in splenocytes and the level of anti-AFP antibody of serum from immunized mice respectively. In vivo tumor challenge were carried out to assess the immune effect of the recombinant vaccine. Results: By recombinant mAFP/HSP70 vaccine immunization, the results of ELISPOT and ELISA showed that the number of splenic cells producing IFN-γ and the level of anti-AFP antibody of serum were significantly higher in mAFP/HSP70 group than those in mAFP and HSP70 groups (108.50±11.70 IFN-γ spots/106 cells vs 41.60±10.40 IFN-γ spots/106 cells, 7.32±3.14 IFN-γ spots/106 cells, P<0.01; 156.32±10.42 μg/mL vs 66.52±7.35 μg/mL, 5.73±2.89 μg/mL, P<0.01). The tumor volume in mAFP/HSP70 group was significantly smaller than that in mAFP and HSP70 groups (42.44±7.14 mm3 vs 392.23±12.46 mm3, 838.63±13.84 mm3, P<0.01). Conclusions: The study further confirmed the function of heat shock protein 70's immune adjuvant. Sequential immunization with recombinant mAFP/HSP70 vaccine could generate effective antitumor immunity on AFP-producing tumor. The recombined mAFP/HSP70 vaccine may be suitable for serving as an immunotherapy for hepatocellular carcinoma.

Strong positive selection and recombination drive the antigenic variation of the PilE protein of the human pathogen Neisseria meningitidis.

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Andrews, T Daniel; Gojobori, Takashi

2004-01-01

The PilE protein is the major component of the Neisseria meningitidis pilus, which is encoded by the pilE/pilS locus that includes an expressed gene and eight homologous silent fragments. The silent gene fragments have been shown to recombine through gene conversion with the expressed gene and thereby provide a means by which novel antigenic variants of the PilE protein can be generated. We have analyzed the evolutionary rate of the pilE gene using the nucleotide sequence of two complete pilE/pilS loci. The very high rate of evolution displayed by the PilE protein appears driven by both recombination and positive selection. Within the semivariable region of the pilE and pilS genes, recombination appears to occur within multiple small sequence blocks that lie between conserved sequence elements. Within the hypervariable region, positive selection was identified from comparison of the silent and expressed genes. The unusual gene conversion mechanism that operates at the pilE/pilS locus is a strategy employed by N. meningitidis to enhance mutation of certain regions of the PilE protein. The silent copies of the gene effectively allow "parallelized" evolution of pilE, thus enabling the encoded protein to rapidly explore a large area of sequence space in an effort to find novel antigenic variants.

Reassembly of S-layer proteins

International Nuclear Information System (INIS)

Pum, Dietmar; Sleytr, Uwe B

2014-01-01

Crystalline bacterial cell surface layers (S-layers) represent the outermost cell envelope component in a broad range of bacteria and archaea. They are monomolecular arrays composed of a single protein or glycoprotein species and represent the simplest biological membranes developed during evolution. They are highly porous protein mesh works with unit cell sizes in the range of 3 to 30 nm, and pore sizes of 2 to 8 nm. S-layers are usually 5 to 20 nm thick (in archaea, up to 70 nm). S-layer proteins are one of the most abundant biopolymers on earth. One of their key features, and the focus of this review, is the intrinsic capability of isolated native and recombinant S-layer proteins to form self-assembled mono- or double layers in suspension, at solid supports, the air-water interface, planar lipid films, liposomes, nanocapsules, and nanoparticles. The reassembly is entropy-driven and a fascinating example of matrix assembly following a multistage, non-classical pathway in which the process of S-layer protein folding is directly linked with assembly into extended clusters. Moreover, basic research on the structure, synthesis, genetics, assembly, and function of S-layer proteins laid the foundation for their application in novel approaches in biotechnology, biomimetics, synthetic biology, and nanotechnology. (topical review)

Recombination homeostasis of meiosis during spermatogenesis under nicotine treatment

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Zhai Jingli

2018-01-01

Full Text Available Cigarette smoking can affect male fertility via the quality of semen. To explore the effects of nicotine, a major component of cigarettes, on meiotic recombination during spermatogenesis, C57BL/6J male mice were injected with nicotine at a dosage of 0.2 mg/100 g body weight daily for 35 days (nicotine-treated group; mice in the control group were injected with isopycnic normal saline. According to previous expression profiles of mouse sperm, a subset of meiosis-related genes was pooled using bioinformatic analysis. Protein expression was compared between the two groups using by Western blotting and immunohistochemistry. Recombination frequency during the meiosis phase of spermatogenesis was estimated by combined use of chromosome spread and immunofluorescence staining in mouse testes. Data mining analysis indicated that 4 genes that express meiotic topoisomerase-like protein SPO11, MutS protein homolog 4 (MSH4, strand exchange protein RAD51 and MutL protein homologue 1 (MLH1, were associated with the meiosis recombination process. The results of Western blotting and immunohistochemistry further showed that the protein expression of SPO11 (0.73-fold and MSH4 (0.73-fold was downregulated in murine testes after nicotine treatment, whereas the protein expression of both RAD51 (2.06-fold and MLH1 (1.40-fold was upregulated. Unexpectedly, we did not detect a significant difference in recombination frequency in meiosis during spermatogenesis in the nicotine-treated group as compared to the control. Taken together, these results indicate that nicotine can affect the expression profile of restructuring-related genes, but it does not significantly change the recombination frequency during male meiosis. These findings suggest there is a self-regulating mechanism during meiotic chromosome restructuring in male mice that responds to environmental stress.

The potential of shifting recombination hotspots to increase genetic gain in livestock breeding.

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Gonen, Serap; Battagin, Mara; Johnston, Susan E; Gorjanc, Gregor; Hickey, John M

2017-07-04

This study uses simulation to explore and quantify the potential effect of shifting recombination hotspots on genetic gain in livestock breeding programs. We simulated three scenarios that differed in the locations of quantitative trait nucleotides (QTN) and recombination hotspots in the genome. In scenario 1, QTN were randomly distributed along the chromosomes and recombination was restricted to occur within specific genomic regions (i.e. recombination hotspots). In the other two scenarios, both QTN and recombination hotspots were located in specific regions, but differed in whether the QTN occurred outside of (scenario 2) or inside (scenario 3) recombination hotspots. We split each chromosome into 250, 500 or 1000 regions per chromosome of which 10% were recombination hotspots and/or contained QTN. The breeding program was run for 21 generations of selection, after which recombination hotspot regions were kept the same or were shifted to adjacent regions for a further 80 generations of selection. We evaluated the effect of shifting recombination hotspots on genetic gain, genetic variance and genic variance. Our results show that shifting recombination hotspots reduced the decline of genetic and genic variance by releasing standing allelic variation in the form of new allele combinations. This in turn resulted in larger increases in genetic gain. However, the benefit of shifting recombination hotspots for increased genetic gain was only observed when QTN were initially outside recombination hotspots. If QTN were initially inside recombination hotspots then shifting them decreased genetic gain. Shifting recombination hotspots to regions of the genome where recombination had not occurred for 21 generations of selection (i.e. recombination deserts) released more of the standing allelic variation available in each generation and thus increased genetic gain. However, whether and how much increase in genetic gain was achieved by shifting recombination hotspots depended

The Effects of the Recombinant CCR5 T4 Lysozyme Fusion Protein on HIV-1 Infection.

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Qingwen Jin

Full Text Available Insertion of T4 lysozyme (T4L into the GPCR successfully enhanced GPCR protein stability and solubilization. However, the biological functions of the recombinant GPCR protein have not been analyzed.We engineered the CCR5-T4L mutant and expressed and purified the soluble recombinant protein using an E.coli expression system. The antiviral effects of this recombinant protein in THP-1 cell lines, primary human macrophages, and PBMCs from different donors were investigated. We also explored the possible mechanisms underlying the observed antiviral effects.Our data showed the biphasic inhibitory and promotion effects of different concentrations of soluble recombinant CCR5-T4L protein on R5 tropic human immunodeficiency virus-1 (HIV-1 infection in THP-1 cell lines, human macrophages, and PBMCs from clinical isolates. We demonstrated that soluble recombinant CCR5-T4L acts as a HIV-1 co-receptor, interacts with wild type CCR5, down-regulates the surface CCR5 expression in human macrophages, and interacts with CCL5 to inhibit macrophage migration. Using binding assays, we further determined that recombinant CCR5-T4L and [125I]-CCL5 compete for the same binding site on wild type CCR5.Our results suggest that recombinant CCR5-T4L protein marginally promotes HIV-1 infection at low concentrations and markedly inhibits infection at higher concentrations. This recombinant protein may be helpful in the future development of anti-HIV-1 therapeutic agents.

Improved eco-friendly recombinant Anabaena sp. strain PCC7120 with enhanced nitrogen biofertilizer potential.

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Chaurasia, Akhilesh Kumar; Apte, Shree Kumar

2011-01-01

Photosynthetic, nitrogen-fixing Anabaena strains are native to tropical paddy fields and contribute to the carbon and nitrogen economy of such soils. Genetic engineering was employed to improve the nitrogen biofertilizer potential of Anabaena sp. strain PCC7120. Constitutive enhanced expression of an additional integrated copy of the hetR gene from a light-inducible promoter elevated HetR protein expression and enhanced functional heterocyst frequency in the recombinant strain. The recombinant strain displayed consistently higher nitrogenase activity than the wild-type strain and appeared to be in homeostasis with compatible modulation of photosynthesis and respiration. The enhanced combined nitrogen availability from the recombinant strain positively catered to the nitrogen demand of rice seedlings in short-term hydroponic experiments and supported better growth. The engineered strain is stable, eco-friendly, and useful for environmental application as nitrogen biofertilizer in paddy fields.

Mutagenic Potential ofBos taurus Papillomavirus Type 1 E6 Recombinant Protein: First Description

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Rodrigo Pinheiro Araldi

2015-01-01

Full Text Available Bovine papillomavirus (BPV is considered a useful model to study HPV oncogenic process. BPV interacts with the host chromatin, resulting in DNA damage, which is attributed to E5, E6, and E7 viral oncoproteins activity. However, the oncogenic mechanisms of BPV E6 oncoprotein per se remain unknown. This study aimed to evaluate the mutagenic potential of Bos taurus papillomavirus type 1 (BPV-1 E6 recombinant oncoprotein by the cytokinesis-block micronucleus assay (CBMNA and comet assay (CA. Peripheral blood samples of five calves were collected. Samples were subjected to molecular diagnosis, which did not reveal presence of BPV sequences. Samples were treated with 1 μg/mL of BPV-1 E6 oncoprotein and 50 μg/mL of cyclophosphamide (positive control. Negative controls were not submitted to any treatment. The samples were submitted to the CBMNA and CA. The results showed that BPV E6 oncoprotein induces clastogenesis per se, which is indicative of genomic instability. These results allowed better understanding the mechanism of cancer promotion associated with the BPV E6 oncoprotein and revealed that this oncoprotein can induce carcinogenesis per se. E6 recombinant oncoprotein has been suggested as a possible vaccine candidate. Results pointed out that BPV E6 recombinant oncoprotein modifications are required to use it as vaccine.

Serum S100B: a potential biomarker for suicidality in adolescents?

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Tatiana Falcone

Full Text Available BACKGROUND: Studies have shown that patients suffering from depression or schizophrenia often have immunological alterations that can be detected in the blood. Others reported a possible link between inflammation, a microgliosis and the blood-brain barrier (BBB in suicidal patients. Serum S100B is a marker of BBB function commonly used to study cerebrovascular wall function. METHODS: We measured levels of S100B in serum of 40 adolescents with acute psychosis, 24 adolescents with mood disorders and 20 healthy controls. Patients were diagnosed according to DSM-IV TR criteria. We evaluated suicidal ideation using the suicidality subscale of the Brief Psychiatric Rating Scale for Children (BPRS-C. RESULTS: Serum S100B levels were significantly higher (p<0.05 and correlated to severity of suicidal ideation in patients with psychosis or mood disorders, independent of psychiatric diagnosis. Patients with a BPRS-C suicidality subscores of 1-4 (low suicidality had mean serum S100B values +/- SEM of 0.152+/-0.020 ng/mL (n = 34 compared to those with BPRS-C suicidality subscores of 5-7 (high suicidality with a mean of 0.354+/-0.044 ng/mL (n = 30. This difference was statistically significant (p<0.05. CONCLUSION: Our data support the use of S100B as an adjunctive biomarker to assess suicidal risk in patients with mood disorders or schizophrenia.

A novel multi-epitope recombined protein for diagnosis of human brucellosis.

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Yin, Dehui; Li, Li; Song, Xiuling; Li, Han; Wang, Juan; Ju, Wen; Qu, Xiaofeng; Song, Dandan; Liu, Yushen; Meng, Xiangjun; Cao, Hongqian; Song, Weiyi; Meng, Rizeng; Liu, Jinhua; Li, Juan; Xu, Kun

2016-05-21

In epidemic regions of the world, brucellosis is a reemerging zoonosis with minimal mortality but is a serious public hygiene problem. Currently, there are various methods for brucellosis diagnosis, however few of them are available to be used to diagnose, especially for serious cross-reaction with other bacteria. To overcome this disadvantage, we explored a novel multi-epitope recombinant protein as human brucellosis diagnostic antigen. We established an indirect enzyme-linked immunosorbent assay (ELISA) based on this recombinant protein. 248 sera obtained from three different groups including patients with brucellosis (146 samples), non-brucellosis patients (82 samples), and healthy individuals (20 samples) were tested by indirect ELISA. To evaluate the assay, a receiver-operating characteristic (ROC) analysis and immunoblotting were carried out using these characterized serum samples. For this test, the area under the ROC curve was 0.9409 (95 % confidence interval, 0.9108 to 0.9709), and a sensitivity of 88.89 % and a specificity of 85.54 % was given with a cutoff value of 0.3865 from this ROC analysis. The Western blot results indicate that it is feasible to differentiate human brucellosis and non-brucellosis with the newly established method based on this recombinant protein. Our results obtained high diagnostic accuracy of the ELISA assay which encourage the use of this novel recombinant protein as diagnostic antigen to implement serological diagnosis of brucellosis.

Impact of S100A4 Expression on Clinicopathological Characteristics and Prognosis in Pancreatic Cancer: A Meta-Analysis

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Shanshan Huang

2016-01-01

Full Text Available Background. The small Ca2+-binding protein S100A4 is identified as a metastasis-associated or metastasis-inducing protein in various types of cancer. The goal of this meta-analysis was to evaluate the relationship between S100A4 expression and clinicopathological characteristics and prognosis of patients with pancreatic cancer. Methods. A comprehensive literature search was carried out in the electronic databases PubMed and Chinese CNKI. Only the studies reporting the correlation between S100A4 expression and clinicopathological characteristics or overall survival (OS of patients with pancreatic cancer are enrolled. Extracted data was analyzed using the RevMan 5.3 software to calculate the pooled relative risks (95% confidence interval, CI for statistical analyses. Results. Seven studies including a total of 474 patients were enrolled into this meta-analysis. Negative expression of S100A4 was significantly associated with higher 3-year OS rate (RR = 3.92, 95% CI = 2.24–6.87, P<0.0001, compared to S100A4-positive cases. Moreover, negative expression of S100A4 was also related to N0 stage for lymph node metastasis (RR = 2.15, 95% CI = 1.60–2.88, P<0.0001. However, S100A4 expression was not significantly correlated with histological types and distant metastasis status. Conclusion. S100A4 expression represents a potential marker for lymph node metastasis of pancreatic cancer and a potential unfavorable factor for prognosis of patients with this disease.

Vaccine potential of recombinant cathepsin B against Fasciola gigantica.

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Chantree, Pathanin; Phatsara, Manussabhorn; Meemon, Krai; Chaichanasak, Pannigan; Changklungmoa, Narin; Kueakhai, Pornanan; Lorsuwannarat, Natcha; Sangpairoj, Kant; Songkoomkrong, Sineenart; Wanichanon, Chaitip; Itagaki, Tadashi; Sobhon, Prasert

2013-09-01

In Fasciola gigantica, cathepsin Bs, especially cathepsin B2 and B3 are expressed in early juvenile stages, and are proposed to mediate the invasion of host tissues. Thus they are thought to be the target vaccine candidates that can block the invasion and migration of the juvenile parasite. To evaluate their vaccine potential, the recombinant cathepsin B2 (rFgCatB2) and cathepsin B3 (rFgCatB3) were expressed in yeast, Pichia pastoris, and used to immunize mice in combination with Freund's adjuvant to evaluate the protection against the infection by F. gigantica metacercariae, and the induction of immune responses. Mice immunized with both recombinant proteins exhibited high percent of parasite reduction at 60% for rFgCatB2 and 66% for rFgCatB3. Immunization by both antigens induced continuously increasing levels of IgG1 and IgG2a with a higher level of IgG1 isotype, indicating the mixed Th1/Th2 responses with Th2 predominating. When examined individually, the higher levels of IgG1 and IgG2a were correlated with the lower numbers of worm recoveries. Thus, both cathepsin B2 and cathepsin B3 are plausible vaccine candidates whose potential should be further tested in large economic animals. Copyright © 2013 Elsevier Inc. All rights reserved.

Generation of Recombinant Schmallenberg Virus Nucleocapsid Protein in Yeast and Development of Virus-Specific Monoclonal Antibodies

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Justas Lazutka

2014-01-01

Full Text Available Schmallenberg virus (SBV, discovered in continental Europe in late 2011, causes mild clinical signs in adult ruminants, including diarrhoea and reduced milk yield. However, fetal infection can lead to severe malformation in newborn offspring. To develop improved reagents for SBV serology, a high-level yeast expression system was employed to produce recombinant SBV nucleocapsid (N protein. Recombinant SBV N protein was investigated as an antigen in SBV-specific IgG enzyme immunoassay and used for generation of monoclonal antibodies (MAbs. Yeast-expressed SBV N protein was reactive with anti-SBV IgG-positive cow serum specimens collected from different farms of Lithuania. After immunization of mice with recombinant SBV N protein, four MAbs were generated. The MAbs raised against recombinant SBV N protein reacted with native viral nucleocapsids in SBV-infected BHK cells by immunofluorescence assay. The reactivity of recombinant N protein with SBV-positive cow serum specimens and the ability of the MAbs to recognize virus-infected cells confirm the antigenic similarity between yeast-expressed SBV N protein and native viral nucleocapsids. Our study demonstrates that yeast expression system is suitable for high-level production of recombinant SBV N protein and provides the first evidence on the presence of SBV-specific antibodies in cow serum specimens collected in Lithuania.

S100 calcium binding protein B as a biomarker of delirium duration in the intensive care unit – an exploratory analysis

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Khan BA

2013-12-01

Full Text Available Babar A Khan,1–3 Mark O Farber,1 Noll Campbell,2–5 Anthony Perkins,2,3 Nagendra K Prasad,6 Siu L Hui,1–3 Douglas K Miller,1–3 Enrique Calvo-Ayala,1 John D Buckley,1 Ruxandra Ionescu,1 Anantha Shekhar,1 E Wesley Ely,7,8 Malaz A Boustani1–3 1Indiana University School of Medicine, 2Indiana University Center for Aging Research, 3Regenstrief Institute, Inc., 4Wishard Health Services, Indianapolis, 5Department of Pharmacy Practice, Purdue University College of Pharmacy, West Lafayette, 6Indiana University Melvin and Bren Simon Cancer Center, Indianapolis, IN, 7Vanderbilt University School of Medicine, 8VA Tennessee Valley Geriatric Research Education Clinical Center (GRECC, Nashville, TN, USA Background: Currently, there are no valid and reliable biomarkers to identify delirious patients predisposed to longer delirium duration. We investigated the hypothesis that elevated S100 calcium binding protein B (S100β levels will be associated with longer delirium duration in critically ill patients. Methods: A prospective observational cohort study was performed in the medical, surgical, and progressive intensive care units (ICUs of a tertiary care, university affiliated, and urban hospital. Sixty-three delirious patients were selected for the analysis, with two samples of S100β collected on days 1 and 8 of enrollment. The main outcome measure was delirium duration. Using the cutoff of <0.1 ng/mL and $0.1 ng/mL as normal and abnormal levels of S100β, respectively, on day 1 and day 8, four exposure groups were created: Group A, normal S100β levels on day 1 and day 8; Group B, normal S100β level on day 1 and abnormal S100β level on day 8; Group C, abnormal S100β level on day 1 and normal on day 8; and Group D, abnormal S100β levels on both day 1 and day 8. Results: Patients with abnormal levels of S100β showed a trend towards higher delirium duration (P=0.076; Group B (standard deviation (7.0 [3.2] days, Group C (5.5 [6.3] days, and Group D

An overview on molecular chaperones enhancing solubility of expressed recombinant proteins with correct folding.

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Mamipour, Mina; Yousefi, Mohammadreza; Hasanzadeh, Mohammad

2017-09-01

The majority of research topics declared that most of the recombinant proteins have been expressed by Escherichia coli in basic investigations. But the majority of high expressed proteins formed as inactive recombinant proteins that are called inclusion body. To overcome this problem, several methods have been used including suitable promoter, environmental factors, ladder tag to secretion of proteins into the periplasm, gene protein optimization, chemical chaperones and molecular chaperones sets. Co-expression of the interest protein with molecular chaperones is one of the common methods The chaperones are a group of proteins, which are involved in making correct folding of recombinant proteins. Chaperones are divided two groups including; cytoplasmic and periplasmic chaperones. Moreover, periplasmic chaperones and proteases can be manipulated to increase the yields of secreted proteins. In this article, we attempted to review cytoplasmic chaperones such as Hsp families and periplasmic chaperones including; generic chaperones, specialized chaperones, PPIases, and proteins involved in disulfide bond formation. Copyright © 2017 Elsevier B.V. All rights reserved.

Production of recombinant proteins in Escherichia coli tagged with the fusion protein CusF3H.

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Vargas-Cortez, Teresa; Morones-Ramirez, Jose Ruben; Balderas-Renteria, Isaias; Zarate, Xristo

2017-04-01

Recombinant protein expression in the bacterium Escherichia coli still is the number one choice for large-scale protein production. Nevertheless, many complications can arise using this microorganism, such as low yields, the formation of inclusion bodies, and the requirement for difficult purification steps. Most of these problems can be solved with the use of fusion proteins. Here, the use of the metal-binding protein CusF3H+ is described as a new fusion protein for recombinant protein expression and purification in E. coli. We have previously shown that CusF produces large amounts of soluble protein, with low levels of formation of inclusion bodies, and that proteins can be purified using IMAC resins charged with Cu(II) ions. CusF3H+ is an enhanced variant of CusF, formed by the addition of three histidine residues at the N-terminus. These residues then can bind Ni(II) ions allowing improved purity after affinity chromatography. Expression and purification of Green Fluorescent Protein tagged with CusF3H+ showed that the mutation did not alter the capacity of the fusion protein to increase protein expression, and purity improved considerably after affinity chromatography with immobilized nickel ions; high yields are obtained after tag-removal since CusF3H+ is a small protein of just 10 kDa. Furthermore, the results of experiments involving expression of tagged proteins having medium to large molecular weights indicate that the presence of the CusF3H+ tag improves protein solubility, as compared to a His-tag. We therefore endorse CusF3H+ as a useful alternative fusion protein/affinity tag for production of recombinant proteins in E. coli. Copyright © 2017 Elsevier Inc. All rights reserved.

Structure of Mycobacterium tuberculosis RuvA, a protein involved in recombination

International Nuclear Information System (INIS)

Prabu, J. Rajan; Thamotharan, S.; Khanduja, Jasbeer Singh; Alipio, Emily Zabala; Kim, Chang-Yub; Waldo, Geoffrey S.; Terwilliger, Thomas C.; Segelke, Brent; Lekin, Tim; Toppani, Dominique; Hung, Li-Wei; Yu, Minmin; Bursey, Evan; Muniyappa, K.; Chandra, Nagasuma R.; Vijayan, M.

2006-01-01

RuvA, a protein from M. tuberculosis H37Rv involved in recombination, has been cloned, expressed, purified and analysed by X-ray crystallography. The process of recombinational repair is crucial for maintaining genomic integrity and generating biological diversity. In association with RuvB and RuvC, RuvA plays a central role in processing and resolving Holliday junctions, which are a critical intermediate in homologous recombination. Here, the cloning, purification and structure determination of the RuvA protein from Mycobacterium tuberculosis (MtRuvA) are reported. Analysis of the structure and comparison with other known RuvA proteins reveal an octameric state with conserved subunit–subunit interaction surfaces, indicating the requirement of octamer formation for biological activity. A detailed analysis of plasticity in the RuvA molecules has led to insights into the invariant and variable regions, thus providing a framework for understanding regional flexibility in various aspects of RuvA function

Cell culture media supplementation of uncommonly used sugars sucrose and tagatose for the targeted shifting of protein glycosylation profiles of recombinant protein therapeutics.

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Hossler, Patrick; McDermott, Sean; Racicot, Christopher; Chumsae, Christopher; Raharimampionona, Haly; Zhou, Yu; Ouellette, David; Matuck, Joseph; Correia, Ivan; Fann, John; Li, Jianmin

2014-01-01

Protein glycosylation is an important post-translational modification toward the structure and function of recombinant therapeutics. The addition of oligosaccharides to recombinant proteins has been shown to greatly influence the overall physiochemical attributes of many proteins. It is for this reason that protein glycosylation is monitored by the developer of a recombinant protein therapeutic, and why protein glycosylation is typically considered a critical quality attribute. In this work, we highlight a systematic study toward the supplementation of sucrose and tagatose into cell culture media for the targeted modulation of protein glycosylation profiles on recombinant proteins. Both sugars were found to affect oligosaccharide maturation resulting in an increase in the percentage of high mannose N-glycan species, as well as a concomitant reduction in fucosylation. The latter effect was demonstrated to increase antibody-dependent cell-mediated cytotoxicity for a recombinant antibody. These aforementioned results were found to be reproducible at different scales, and across different Chinese hamster ovary cell lines. Through the selective supplementation of these described sugars, the targeted modulation of protein glycosylation profiles is demonstrated, as well as yet another tool in the cell culture toolbox for ensuring product comparability. © 2014 American Institute of Chemical Engineers.

Comparison of mRNA, Protein, and Urinary Nucleic Acid Levels of S100A8 and S100A9 between Prostate Cancer and BPH.

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Yun, Seok Joong; Yan, Chunri; Jeong, Pildu; Kang, Ho Won; Kim, Ye-Hwan; Kim, Eun-Ah; Lee, Ok-Jun; Kim, Won Tae; Moon, Sung-Kwon; Kim, Isaac Yi; Choi, Yung-Hyun; Kim, Wun-Jae

2015-07-01

Infections and inflammation in the prostate play a critical role in carcinogenesis, and S100A8 and S100A9 are key mediators in acute and chronic inflammation. Therefore, we investigated the differences of S100A8/A9 expression between prostate cancer (CaP) and benign prostatic hyperplasia (BPH) tissues, and we evaluated the possibilities of urinary nucleic acids of S100A8/A9 as diagnostic and prognostic markers. Tissues from 132 CaP patients who underwent prostatectomy or transurethral resection and 90 BPH patients who underwent transurethral prostatectomy were assessed.sd In addition, S100A8 and S100A9 nucleic acid levels were measured in the urine of 283 CaP patients and 363 BPH controls. S100A8 and S100A9 mRNA levels were lower in CaP than BPH tissues (P BPH tissues stained more strongly for both S100A8 and S100A9 than CaP tissues (P BPH (P = 0.001 and BPH. Both were more highly expressed in patients with aggressive disease and shorter biochemical recurrence-free time. S100A8/A9 urinary cell-free nucleic acid levels correlated positively with expression levels obtained from tissue staining. Therefore, S100A8/A9 measurement in tissues and urine may have diagnostic and prognostic value in CaP.

Capillary gel electrophoresis for the quantification and purity determination of recombinant proteins in inclusion bodies.

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Espinosa-de la Garza, Carlos E; Perdomo-Abúndez, Francisco C; Campos-García, Víctor R; Pérez, Néstor O; Flores-Ortiz, Luis F; Medina-Rivero, Emilio

2013-09-01

In this work, a high-resolution CGE method for quantification and purity determination of recombinant proteins was developed, involving a single-component inclusion bodies (IBs) solubilization solution. Different recombinant proteins expressed as IBs were used to show method capabilities, using recombinant interferon-β 1b as the model protein for method validation. Method linearity was verified in the range from 0.05 to 0.40 mg/mL and a determination coefficient (r(2) ) of 0.99 was obtained. The LOQs and LODs were 0.018 and 0.006 mg/mL, respectively. RSD for protein content repeatability test was 2.29%. In addition, RSD for protein purity repeatability test was 4.24%. Method accuracy was higher than 90%. Specificity was confirmed, as the method was able to separate recombinant interferon-β 1b monomer from other aggregates and impurities. Sample content and purity was demonstrated to be stable for up to 48 h. Overall, this method is suitable for the analysis of recombinant proteins in IBs according to the attributes established on the International Conference for Harmonization guidelines. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Construction of green fluorescent protein-tagged recombinant iridovirus to assess viral replication.

Science.gov (United States)

Huang, Youhua; Huang, Xiaohong; Cai, Jia; Ye, Fuzhou; Guan, Liya; Liu, Hong; Qin, Qiwei

2011-09-01

Green fluorescent protein-tagged recombinant virus has been successfully applied to observing the infective dynamics and evaluating viral replication. Here, we identified soft-shelled turtle iridovirus (STIV) ORF55 as an envelope protein (VP55), and developed a recombinant STIV expressing an enhanced green fluorescent protein (EGFP) fused to VP55 (EGFP-STIV). Recombinant EGFP-STIV shared similar single-step growth curves and ultrastructural morphology with wild type STIV (wt-STIV). The green fluorescence distribution during EGFP-STIV infection was consistent with the intracellular distribution of VP55 which was mostly co-localized with virus assembly sites. Furthermore, EGFP-STIV could be used to evaluate viral replication conveniently under drug treatment, and the result showed that STIV replication was significantly inhibited after the addition of antioxidant pyrrolidine dithiocarbamate (PDTC). Thus, the EGFP-tagged recombinant iridovirus will not only be useful for further investigations on the viral replicative dynamics, but also provide an alternative simple strategy to screen for antiviral substances. Copyright © 2011 Elsevier B.V. All rights reserved.

Overview of the purification of recombinant proteins.

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Wingfield, Paul T

2015-04-01

When the first version of this unit was written in 1995, protein purification of recombinant proteins was based on a variety of standard chromatographic methods and approaches, many of which were described and mentioned throughout Current Protocols in Protein Science. In the interim, there has been a shift toward an almost universal usage of the affinity or fusion tag. This may not be the case for biotechnology manufacture where affinity tags can complicate producing proteins under regulatory conditions. Regardless of the protein expression system, questions are asked as to which and how many affinity tags to use, where to attach them in the protein, and whether to engineer a self-cleavage system or simply leave them on. We will briefly address some of these issues. Also, although this overview focuses on E.coli, protein expression and purification, other commonly used expression systems are mentioned and, apart from cell-breakage methods, protein purification methods and strategies are essentially the same. Copyright © 2015 John Wiley & Sons, Inc.

Recombinant dioscorins of the yam storage protein expressed in Escherichia coli exhibit antioxidant and immunomodulatory activities.

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Jheng, Yi-Jyun; Tsai, Wei-Yi; Chen, Kuo-Hsuan; Lin, Kuo-Wei; Chyan, Chia-Lin; Yang, Ching-Chi; Lin, Kuo-Chih

2012-09-01

Dioscorins, the major storage proteins in yam tubers, exhibit biochemical and immunomodulatroy activities. To investigate the potential application of dioscorins in biomedical research, we expressed the dioscorin genes Dj-dioA3 and Dp-dioA2 from Dioscorea japonica and Dioscorea pseudojaponica, respectively, in E. coli and routinely obtained approximately 15 mg proteins per liter Escherichia coli culture (mg/L) to 30 mg/L of rDj-dioscorinA3 and 4 to 8 mg/L of rDp-dioscorinA2. Western blot analyses revealed that both recombinant dioscorins contained epitopes with similar antigenicities to those of the native dioscorins. Results from dithiothreitol (DTT) treatment followed by monobromobimane (mBBr) staining showed that both recombinant dioscorins, like the native dioscorins, contain an intramolecular disulfide bond between Cys(28) and Cys(187) residues. Circular dichroism spectroscopy findings indicated that the secondary structural contents of the recombinant dioscorins showed high similarity to those of their corresponding native dioscorins. Both recombinant dioscorins, like the native dioscorins, exhibited 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and Toll-like receptor 4 signaling activities, and stimulated the phagocytosis of E. coli by macrophage. Overall, our results indicated that substantial amounts of recombinant dioscorins can be purified easily from E. coli and that these recombinant dioscorins are appropriate for application in future investigations of the biomedical functions of dioscorins. Copyright © 2012 Elsevier Inc. All rights reserved.

Production of Polyclonal Antibodies to a Recombinant Coat Protein of Potato mop-top virus

Czech Academy of Sciences Publication Activity Database

Čeřovská, Noemi; Moravec, Tomáš; Rosecká, Pavla; Dědič, P.; Filigarová, Marie

2003-01-01

Roč. 151, č. 4 (2003), s. 195-200 ISSN 0931-1785 R&D Projects: GA ČR GA522/01/1121 Institutional research plan: CEZ:AV0Z5038910 Keywords : potato mop-top virus * recombinant coat protein * Escherichia Coli Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.557, year: 2003

Characterization of an Sf-rhabdovirus-negative Spodoptera frugiperda cell line as an alternative host for recombinant protein production in the baculovirus-insect cell system.

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Maghodia, Ajay B; Geisler, Christoph; Jarvis, Donald L

2016-06-01

Cell lines derived from the fall armyworm, Spodoptera frugiperda (Sf), are widely used as hosts for recombinant protein production in the baculovirus-insect cell system (BICS). However, it was recently discovered that these cell lines are contaminated with a virus, now known as Sf-rhabdovirus [1]. The detection of this adventitious agent raised a potential safety issue that could adversely impact the BICS as a commercial recombinant protein production platform. Thus, we examined the properties of Sf-RVN, an Sf-rhabdovirus-negative Sf cell line, as a potential alternative host. Nested RT-PCR assays showed Sf-RVN cells had no detectable Sf-rhabdovirus over the course of 60 passages in continuous culture. The general properties of Sf-RVN cells, including their average growth rates, diameters, morphologies, and viabilities after baculovirus infection, were virtually identical to those of Sf9 cells. Baculovirus-infected Sf-RVN and Sf9 cells produced equivalent levels of three recombinant proteins, including an intracellular prokaryotic protein and two secreted eukaryotic glycoproteins, and provided similar N-glycosylation patterns. In fact, except for the absence of Sf-rhabdovirus, the only difference between Sf-RVN and Sf9 cells was SF-RVN produced higher levels of infectious baculovirus progeny. These results show Sf-RVN cells can be used as improved, alternative hosts to circumvent the potential safety hazard associated with the use of Sf-rhabdovirus-contaminated Sf cells for recombinant protein manufacturing with the BICS. Copyright © 2016 Elsevier Inc. All rights reserved.

A dual protease approach for expression and affinity purification of recombinant proteins.

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Raran-Kurussi, Sreejith; Waugh, David S

2016-07-01

We describe a new method for affinity purification of recombinant proteins using a dual protease protocol. Escherichia coli maltose binding protein (MBP) is employed as an N-terminal tag to increase the yield and solubility of its fusion partners. The MBP moiety is then removed by rhinovirus 3C protease, prior to purification, to yield an N-terminally His6-tagged protein. Proteins that are only temporarily rendered soluble by fusing them to MBP are readily identified at this stage because they will precipitate after the MBP tag is removed by 3C protease. The remaining soluble His6-tagged protein, if any, is subsequently purified by immobilized metal affinity chromatography (IMAC). Finally, the N-terminal His6 tag is removed by His6-tagged tobacco etch virus (TEV) protease to yield the native recombinant protein, and the His6-tagged contaminants are removed by adsorption during a second round of IMAC, leaving only the untagged recombinant protein in the column effluent. The generic strategy described here saves time and effort by removing insoluble aggregates at an early stage in the process while also reducing the tendency of MBP to "stick" to its fusion partners during affinity purification. Published by Elsevier Inc.

Protein expression of Myt272-3 recombinant clone and in silico ...

African Journals Online (AJOL)

Purpose: To investigate the expression of Myt272-3 recombinant protein and also to predict a possible protein vaccine candidate against Mycobacterium tuberculosis. Methods: Myt272-3 protein was expressed in pET30a+-Myt272-3 clone. The purity of the protein was determined using Dynabeads® His-Tag Isolation ...

Molecular basis of interactions between mitochondrial proteins and hydroxyapatite in the presence of Triton X-100, as revealed by proteomic and recombinant techniques.

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Yamamoto, Takenori; Tamaki, Haruna; Katsuda, Chie; Nakatani, Kiwami; Terauchi, Satsuki; Terada, Hiroshi; Shinohara, Yasuo

2013-08-02

Hydroxyapatite chromatography is a very important step in the purification of voltage-dependent anion channels (VDACs) and several members of solute carrier family 25 (Slc25) from isolated mitochondria. In the presence of Triton X-100, VDACs and Slc25 members present a peculiar property, i.e., a lack of interaction with hydroxyapatite, resulting in their presence in the flow-through fraction of hydroxyapatite chromatography. This property has allowed selective isolation of VDACs and Slc25 members from a mixture of total mitochondrial proteins. However, the reason why only these few proteins are selectively obtained in the presence of Triton X-100 from the flow-though fraction of hydroxyapatite chromatography has not yet been adequately understood. In this study, when we examined the protein species in the flow-through fractions by proteomic analysis, VDAC isoforms, Slc25 members, and some other membrane proteins were identified. All the mitochondrial proteins had in common high hydrophobicity over their entire protein sequences. When the proteins were fused to soluble proteins, the fused proteins showed affinity for hydroxyapatite even in the presence of Triton X-100. Based on these results, we discussed the molecular basis of the interactions between proteins and hydroxyapatite in the presence of Triton X-100. Copyright © 2013 Elsevier B.V. All rights reserved.

A Library of Plasmodium vivax Recombinant Merozoite Proteins Reveals New Vaccine Candidates and Protein-Protein Interactions

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Hostetler, Jessica B.; Sharma, Sumana; Bartholdson, S. Josefin; Wright, Gavin J.; Fairhurst, Rick M.; Rayner, Julian C.

2015-01-01

suggesting that the proteins are natively folded and functional. This screen also identified two novel protein-protein interactions, between P12 and PVX_110945, and between MSP3.10 and MSP7.1, the latter of which was confirmed by surface plasmon resonance. Conclusions/Significance We produced a new library of recombinant full-length P. vivax ectodomains, established that the majority of them contain tertiary structure, and used them to identify predicted and novel protein-protein interactions. As well as identifying new interactions for further biological studies, this library will be useful in identifying P. vivax proteins with vaccine potential, and studying P. vivax malaria pathogenesis and immunity. Trial Registration ClinicalTrials.gov NCT00663546 PMID:26701602

Bicistronic expression plasmid for the rapid production of recombinant fused proteins in Escherichia coli.

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Yero, Daniel; Pajón, Rolando; Niebla, Olivia; Sardiñas, Gretel; Vivar, Isbel; Perera, Yasser; García, Darien; Delgado, Maité; Cobas, Karem

2006-04-01

In the post-genomic era, every aspect of the production of proteins must be accelerated. In this way, several vectors are currently exploited for rapid production of recombinant proteins in Escherichia coli. N-terminal fusions to the first 47 amino acids of the LpdA (dihydrolipoamide dehydrogenase A) protein of Neisseria meningitidis have been shown to increase the expression of recombinant proteins. Consequently, we have constructed a modified N-terminal LpdA fusion vector, introducing the blue/white colony selection by exploiting a bicistronic gene organization. In the new vector, the sequence encoding the first 47 amino acids of meningococcal LpdA and the alpha-peptide sequence of beta-galactosidase were connected via a ribosome-binding site, and two MCSs (multiple cloning sites) were located surrounding the latter, allowing efficient cloning by colour selection of recombinants. The vector was also improved with the addition of a C-terminal polyhistidine tag, and an EKS (enterokinase recognition sequence) immediately after the LpdA fusion sequence. The new plasmid was employed in the expression and purification of six different bacterial polypeptides. One of these recombinant proteins, P6 protein from Haemophilus influenzae, was used as a model and its N-terminal fusion sequence was totally removed from the recombinant version after incubation with the enterokinase protease, while the polyhistidine tail successfully allowed the purification of the unfused protein from the protease reaction. Two completely new neisserial vaccine candidates, NMB0088 and NMB1126 proteins, were cloned, expressed and purified using this system. To our knowledge, this constitutes the first report of the cloning and expression of these proteins in E. coli.

Recombinant α-actinin subunit antigens of Trichomonas vaginalis as potential vaccine candidates in protecting against trichomoniasis.

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Xie, Yi-Ting; Gao, Jiang-Mei; Wu, Ya-Ping; Tang, Petrus; Hide, Geoff; Lai, De-Hua; Lun, Zhao-Rong

2017-02-16

Human trichomoniasis caused by Trichomonas vaginalis is one of the most common sexually transmitted diseases with more than 200 million cases worldwide. It has caused a series of health problems to patients. For prevention and control of infectious diseases, vaccines are usually considered as one of the most cost-efficient tools. However, until now, work on the development of T. vaginalis vaccines is still mainly focused on the screening of potential immunogens. Alpha-actinin characterized by high immunogenicity in T. vaginalis was suggested as a promising candidate. Therefore, the purpose of this study was to evaluate the protective potency of recombinant α-actinin against T. vaginalis infection in a mouse intraperitoneal model. Two selected coding regions of α-actinin (ACT-F, 14-469 aa and ACT-T, 462-844 aa) amplified from cDNA were cloned into pET-32a (+) expression vector and transfected into BL21 cells. After induction with IPTG and purification with electroelution, the two recombinant fusion proteins were emulsified in Freund's adjuvant (FA) and used to immunize BALB/C mice. Following intraperitoneal inoculation with T. vaginalis, the survival rate of mice was monitored for the assessment of protective potency. After immunization, the antibody level in mouse serum was assessed by ELISA, splenocyte proliferation response was detected with CCK8 and cytokines in the supernatant of splenocytes were quantified with a cytometric bead-based assay. We successfully obtained purified ACT-F (70.33 kDa) and ACT-T (61.7kDa). Both recombinant proteins could provide significant protection against T. vaginalis challenge, especially ACT-T (with 100% protection within one month). Meanwhile, high levels of specific total IgG and subtypes (IgG1 > IgG2a) were detected in sera from the immunized mice. Our results also revealed a statistically significant increase in splenocyte proliferation and related cytokine (IFN-γ, IL-6, IL-17A and IL-10) production after repeated

Change and significance of serum inflammatory factors, NSE, S100 protein and stress hormone levels in patients with craniocerebral injury

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Rui-Feng Liu

2017-09-01

Full Text Available Objective: To investigate the change and significance of serum inflammatory factors, neuron specific enolase (NSE, S100 protein and stress hormone levels in patients with brain diseases. Methods: A total of 115 patients with craniocerebral injury were selected as the observation group, according to the Glasgow Coma Scale (GCS, they were divided into light-sized group (n=38, middle-sized group (n=40 and severe-sized group (n=37, at the same time the other 120 healthy subjects were selected as the control group. The levels of serum inflammatory cytokines [tumor necrosis factor alpha (TNF-α and procalcitonin (PCT], neuron specific enolase (NSE, S100 protein and the stress hormone cortisol [(COR, adrenocorticotropic hormone (ACTH, β-endorphin (β-EP] of both groups were compared. Results: The levels of TNF-α, PCT, NSE, S100, COR, ACTH and β-EP in the observation group were (145.73±19.24 ng/L, (2.41±0.64 ng/mL, (38.11±12.28 ng/mL, (0.87±0.32 μg/L, (818.87±121.14 nmol/L, (107.38±13.94 ng/L, (126.74±39.04 ng/mL, which were significantly higher than control group, the difference was statistically significant; Comparison of indexes among the observation group, NF-α, PCT, NSE, S100, COR, ACTH and β-EP levels in the middle-sized group and severe-sized group were significantly higher than those in the light-sized group, and the levels in the severe-sized group were significantly higher than those of the middle-sized group, the difference was statistically significant. Conclusion: The levels of Serum inflammatory factors, NSE, S100 protein and stress hormone were significantly increased in patients with craniocerebral injury, the level was related to the degree of traumatic brain injury, which could be used as an important indicator to assess the severity of the disease.

Trafficking of endoplasmic reticulum-retained recombinant proteins is unpredictable in Arabidopsis thaliana

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Thomas eDe Meyer

2014-09-01

Full Text Available A wide variety of recombinant proteins has been produced in the dicot model plant, Arabidopsis thaliana. Many of these proteins are targeted for secretion by means of an N terminal endoplasmic reticulum (ER signal peptide. In addition, they can also be designed for ER retention by adding a C terminal H/KDEL-tag. Despite extensive knowledge of the protein trafficking pathways, the final protein destination, especially of such H/KDEL-tagged recombinant proteins, is unpredictable. In this respect, glycoproteins are ideal study objects. Microscopy experiments reveal their deposition pattern and characterization of their N-glycans aids in elucidating the trafficking. Here, we combine microscopy and N glycosylation data generated in Arabidopsis leaves and seeds, and highlight the lack of a decent understanding of heterologous protein trafficking.

An All-Recombinant Protein-Based Culture System Specifically Identifies Hematopoietic Stem Cell Maintenance Factors

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Aki Ieyasu

2017-03-01

Full Text Available Hematopoietic stem cells (HSCs are considered one of the most promising therapeutic targets for the treatment of various blood disorders. However, due to difficulties in establishing stable maintenance and expansion of HSCs in vitro, their insufficient supply is a major constraint to transplantation studies. To solve these problems we have developed a fully defined, all-recombinant protein-based culture system. Through this system, we have identified hemopexin (HPX and interleukin-1α as responsible for HSC maintenance in vitro. Subsequent molecular analysis revealed that HPX reduces intracellular reactive oxygen species levels within cultured HSCs. Furthermore, bone marrow immunostaining and 3D immunohistochemistry revealed that HPX is expressed in non-myelinating Schwann cells, known HSC niche constituents. These results highlight the utility of this fully defined all-recombinant protein-based culture system for reproducible in vitro HSC culture and its potential to contribute to the identification of factors responsible for in vitro maintenance, expansion, and differentiation of stem cell populations.

Characterization of Fluorescent Proteins for Three- and Four-Color Live-Cell Imaging in S. cerevisiae.

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Higuchi-Sanabria, Ryo; Garcia, Enrique J; Tomoiaga, Delia; Munteanu, Emilia L; Feinstein, Paul; Pon, Liza A

2016-01-01

Saccharomyces cerevisiae are widely used for imaging fluorescently tagged protein fusions. Fluorescent proteins can easily be inserted into yeast genes at their chromosomal locus, by homologous recombination, for expression of tagged proteins at endogenous levels. This is especially useful for incorporation of multiple fluorescent protein fusions into a single strain, which can be challenging in organisms where genetic manipulation is more complex. However, the availability of optimal fluorescent protein combinations for 3-color imaging is limited. Here, we have characterized a combination of fluorescent proteins, mTFP1/mCitrine/mCherry for multicolor live cell imaging in S. cerevisiae. This combination can be used with conventional blue dyes, such as DAPI, for potential four-color live cell imaging.

Dynamics and Predictive Potential of Antibodies against Insect-Derived Recombinant Leishmania infantum Proteins during Chemotherapy of Naturally Infected Dogs

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Todolí, Felicitat; Galindo, Inmaculada; Gómez-Sebastián, Silvia; Pérez-Filgueira, Mariano; Escribano, José M.; Alberola, Jordi; Rodríguez-Cortés, Alhelí

2010-01-01

A predictive marker for the success treatment of canine leishmaniasis is required for the application of a more rational therapy protocol, which must improve the probability of cure and reduce Leishmania resistance to drugs. We investigated the dynamics and predictive value of antibodies against insect-derived recombinant L. infantum proteins rKMPII and rTRYP by using an enzyme-linked immunosorbent assay with retrospective serum samples from 36 dogs during treatment of canine leishmaniasis. In the entire group of dogs, concentrations of antibodies against rKMPII and rTRYP significantly decreased earlier than concentrations of antibodies against crude total Leishmania antigen (one versus six months), which suggested that the dynamics of antibodies against recombinant proteins may be useful for assessing clinical improvement after treatment. Interestingly, decreases in antibody concentrations against rKMPII occurred earlier in disease-free dogs than in dogs that remain clinically ill one year after beginning of treatment, which suggested that these antibodies may be useful for predicting disease-free survival one year after the beginning of therapy against canine leishmaniasis. PMID:20439957

Recombinant protein production from stable mammalian cell lines and pools.

Science.gov (United States)

Hacker, David L; Balasubramanian, Sowmya

2016-06-01

We highlight recent developments for the production of recombinant proteins from suspension-adapted mammalian cell lines. We discuss the generation of stable cell lines using transposons and lentivirus vectors (non-targeted transgene integration) and site-specific recombinases (targeted transgene integration). Each of these methods results in the generation of cell lines with protein yields that are generally superior to those achievable through classical plasmid transfection that depends on the integration of the transfected DNA by non-homologous DNA end-joining. This is the main reason why these techniques can also be used for the generation of stable cell pools, heterogenous populations of recombinant cells generated by gene delivery and genetic selection without resorting to single cell cloning. This allows the time line from gene transfer to protein production to be reduced. Copyright © 2016 Elsevier Ltd. All rights reserved.

Application of recombinant hemagglutinin proteins as alternative antigen standards for pandemic influenza vaccines.

Science.gov (United States)

Choi, Yejin; Kwon, Seong Yi; Oh, Ho Jung; Shim, Sunbo; Chang, Seokkee; Chung, Hye Joo; Kim, Do Keun; Park, Younsang; Lee, Younghee

2017-09-01

The single radial immunodiffusion (SRID) assay, used to quantify hemagglutinin (HA) in influenza vaccines, requires reference reagents; however, because centralized production of reference reagents may slow the emergency deployment of vaccines, alternatives are needed. We investigated the production of HA proteins using recombinant DNA technology, rather than a traditional egg-based production process. The HA proteins were then used in an SRID assay as a reference antigen. We found that HA can be quantified in both egg-based and cell-based influenza vaccines when recombinant HAs (rHAs) are used as the reference antigen. Furthermore, we confirmed that rHAs obtained from strains with pandemic potential, such as H5N1, H7N3, H7N9, and H9N2 strains, can be utilized in the SRID assay. The rHA production process takes just one month, in contrast to the traditional process that takes three to four months. The use of rHAs may reduce the time required to produce reference reagents and facilitate timely introduction of vaccines during emergencies.

Dissection of an old protein reveals a novel application: domain D of Staphylococcus aureus Protein A (sSpAD as a secretion - tag

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Paal Michael

2010-11-01

Full Text Available Abstract Background Escherichia coli as a frequently utilized host organism for recombinant protein production offers different cellular locations with distinct qualities. The periplasmic space is often favored for the production of complex proteins due to enhanced disulfide bond formation, increased target product stability and simplified downstream processing. To direct proteins to the periplasmic space rather small proteinaceus tags that can be used for affinity purification would be advantageous. Results We discovered that domain D of the Staphylococcus aureus protein A was sufficient for the secretion of various target proteins into the periplasmic space of E. coli. Our experiments indicated the Sec pathway as the mode of secretion, although N-terminal processing was not observed. Furthermore, the solubility of recombinant fusion proteins was improved for proteins prone to aggregation. The tag allowed a straightforward affinity purification of recombinant fusion protein via an IgG column, which was exemplified for the target protein human superoxide dismutase 1 (SOD. Conclusions In this work we present a new secretion tag that combines several advantages for the production of recombinant proteins in E. coli. Domain D of S. aureus protein A protects the protein of interest against N-terminal degradation, increases target protein solubility and enables a straight-forward purification of the recombinant protein using of IgG columns.

Tunable recombinant protein expression with E. coli in a mixed-feed environment.

Science.gov (United States)

Sagmeister, Patrick; Schimek, Clemens; Meitz, Andrea; Herwig, Christoph; Spadiut, Oliver

2014-04-01

Controlling the recombinant protein production rate in Escherichia coli is of utmost importance to ensure product quality and quantity. Up to now, only the genetic construct, introduced into E. coli, and the specific growth rate of the culture were used to influence and stir the productivity. However, bioprocess technological means to control or even tune the productivity of E. coli are scarce. Here, we present a novel method for the process-technological control over the recombinant protein expression rate in E. coli. A mixed-feed fed-batch bioprocess based on the araBAD promoter expression system using both D-glucose and L-arabinose as assimilable C-sources was designed. Using the model product green fluorescent protein, we show that the specific product formation rate can be efficiently tuned even on the cellular level only via the uptake rate of L-arabinose. This novel approach introduces an additional degree of freedom for the design of recombinant bioprocesses with E. coli. We anticipate that the presented method will result in significant quality and robustness improvement as well as cost and process time reduction for recombinant bacterial bioprocesses in the future.

Combination PPARγ and RXR Agonist Treatment in Melanoma Cells: Functional Importance of S100A2

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Joshua P. Klopper

2010-01-01

Full Text Available Nuclear hormone receptors, including RXR and PPARγ, represent novel therapeutic targets in melanoma. We have previously shown that the DRO subline of the amelanotic melanoma A375 responds to rexinoid and thiazolidinedione (TZD treatment in vitro and in vivo. We performed microarray analysis of A375(DRO after TZD and combination rexinoid/TZD treatment in which the calcium binding protein S100A2 had increased expression after rexinoid or TZD treatment and a synergistic increase to combination treatment. Increased S100A2 expression is dependent on an intact PPARγ receptor, but it is not sufficient to mediate the antiproliferative effects of rexinoid/TZD treatment. Over expression of S100A2 enhanced the effect of rexinoid and TZD treatment while inhibition of S100A2 expression attenuated the response to rexinoid/TZD treatment, suggesting that S100A2 is necessary for optimal response to RXR and PPARγ activation by respective ligands. In summary, we have identified potential downstream mediators of rexinoid and TZD treatment in a poorly differentiated melanoma and found that alterations in S100A2 expression affect RXR and PPARγ signaling in A375(DRO cells. These studies provide insight into potential mechanisms of tumor response or resistance to these novel therapies.

Production of Recombinant and Tagged Proteins in the Hyperthermophilic Archaeon Sulfolobus solfataricus