Search results for "recombinant"
showing 10 items of 1150 documents
The diagnostic plot: a concept for identifying different states of iron deficiency and monitoring the response to epoetin therapy.
2005
Iron balance is regulated by the rate of erythropoiesis and the size of the iron stores. Anemia that accompanies infection, inflammation, and cancer (anemia of chronic disease) features normal or increased iron stores, although patients may have functional iron deficiency, namely, an imbalance between iron requirements of the erythroid marrow and the actual supply. The proportion of hypochromic red cells and the hemoglobin content of reticulocytes are direct indicators of functional iron deficiency. Biochemical markers, especially the soluble transferrin receptor/log ferritin ratio (ferritin index), are useful indicators of the iron supply to erythropoiesis. The relationship between functio…
Two new natural begomovirus recombinants associated with the tomato yellow leaf curl disease co-exist with parental viruses in tomato epidemics in It…
2009
Two tomato geminivirus species co-exist in protected crops in Sicily, Tomato yellow leaf curl Sardinia virus (TYLCSV, found in 1989) and Tomato yellow leaf curl virus (TYLCV, found in 2002), and mixed infections have been detected. In a field survey conducted in 2004, the viral intergenic region (IR) was amplified from infected plants, and molecules apparently hybrid between the two species were found, but only in plants where one or both parental species were also present. Two of these hybrids, named 2/2 and 2/5, were isolated and infectious clones were obtained. They were both readily whitefly-transmitted to tomato plants; clone 2/5 produced symptoms typical of TYLCSV and TYLCV, while clo…
Targeting cancer with peptide aptamers
2011
Renaud Seigneuric 1,2 , Jessica Gobbo 1,2 , Pierre Colas 3 , Carmen Garrido 1,2 1 Heat Shock Proteins and Cancer, INSERM, UMR 866 IFR 100, Faculty of Medicine, 7 Boulevard Jeanne D'Arc, 21000 Dijon, France 2 Universite de Bourgogne, Dijon, France 3 CNRS USR 3151, P2I2 Group, Station Biologique, Roscoff, Bretagne, France Received: June 22, 2011; Accepted: June 24, 2011; Published: June 24, 2011; Correspondence: Renaud Seigneuric, email: // // Abstract A major endeavour in cancer chemotherapy is to develop agents that specifically target a biomolecule of interest. There are two main classes of targeting agents: small molecules and biologics. Among biologics (e.g.: antibodies), DNA, RNA but al…
Tetanus Toxin Inhibits Neuroexocytosis Even When Its Zn2+-dependent Protease Activity Is Removed
1995
Tetanus toxin (TeTX) is a dichain protein that blocks neuroexocytosis, an action attributed previously to Zn(2+)-dependent proteolysis of synaptobrevin (Sbr) by its light chain (LC). Herein, its cleavage of Sbr in rat cerebrocortical synaptosomes was shown to be minimized by captopril, an inhibitor of certain metalloendoproteases, whereas this agent only marginally antagonized the inhibition of noradrenaline release, implicating a second action of the toxin. This hypothesis was proven by preparing three mutants (H233A, E234A, H237A) of the LC lacking the ability to cleave Sbr and reconstituting them with native heavy chain. The resultant dichains were found to block synaptosomal transmitter…
Expression in Escherichia coli of Native and Chimeric Phenolic Acid Decarboxylases with Modified Enzymatic Activities and Method for Screening Recomb…
2001
ABSTRACT Four bacterial phenolic acid decarboxylases (PAD) from Lactobacillus plantarum , Pediococcus pentosaceus , Bacillus subtilis , and Bacillus pumilus were expressed in Escherichia coli , and their activities on p -coumaric, ferulic, and caffeic acids were compared. Although these four enzymes displayed 61% amino acid sequence identity, they exhibit different activities for ferulic and caffeic acid metabolism. To elucidate the domain(s) that determines these differences, chimeric PAD proteins were constructed and expressed in E. coli by exchanging their individual carboxy-terminal portions. Analysis of the chimeric enzyme activities suggests that the C-terminal region may be involved …
Immunoadhesins of interleukin-6 and the IL-6/soluble IL-6R fusion protein hyper-IL-6.
1999
Signal transduction in response to interleukin-6 (IL-6) results from homodimerization of gp130. This dimerization occurs after binding of IL-6 to its surface receptor (IL-6R) and can also be triggered by the complex of soluble IL-6R and IL-6. We fused IL-6 to the constant region of a human IgG1 heavy chain (Fc). IL-6Fc was expressed in COS-7 cells and purified via Protein A Sepharose. Using three different assays we found that the biological activity of this dimeric IL-6 protein is comparable with monomeric IL-6. Recently, we described the designer cytokine Hyper-IL-6 (H-IL-6) in which soluble IL-6R and IL-6 are connected via a flexible peptide linker. This molecule turned out to be 100-100…
A bioactive designer cytokine for human hematopoietic progenitor cell expansion
1997
Efficient expansion of hematopoietic progenitor cells requires, at least, the simultaneous stimulation of the receptors c-kit and gp130. While c-kit is activated by SCF; gp130, in cells which do not express sufficient amounts of IL-6R, can be activated by the complex of soluble IL-6R (sIL-6R) and IL-6. The therapeutic use of IL-6/sIL-6R, however, has been hampered by the high concentrations of the sIL-6R protein required. We have designed a fusion protein of sIL-6R and IL-6, linked by a flexible peptide chain, that was expressed to high levels. On gp130 expressing cells the fusion protein turned out to be fully active at 100 to 1,000-fold lower concentration than the combination of unlinked…
A novel cell model to study the function of the adrenoleukodystrophy-related protein
2006
X-linked adrenoleukodystrophy (X-ALD) is a neurodegenerative disorder due to mutations in the ABCD1 (ALD) gene. ALDRP, the closest homolog of ALDP, has been shown to have partial functional redundancy with ALDP and, when overexpressed, can compensate for the loss-of-function of ALDP. In order to characterize the function of ALDRP and to understand the phenomenon of gene redundancy, we have developed a novel system that allows the controlled expression of the ALDRP-EGFP fusion protein (normal or non-functional mutated ALDRP) using the Tet-On system in H4IIEC3 rat hepatoma cells. The generated stable cell lines express negligible levels of endogenous ALDRP and doxycycline dosage-dependent lev…
Local transient myocardial liposomal gene transfer of inducible nitric oxide synthase does not aggravate myocardial function and fibrosis and leads t…
2010
Microcirculation (2010) 17, 69–78. doi: 10.1111/j.1549-8719.2010.00002.x Abstract Background: This study was designed to explore the effect of transient inducible nitric oxide synthase (iNOS) overexpression via cationic liposome-mediated gene transfer on cardiac function, fibrosis, and microvascular perfusion in a porcine model of chronic ischemia. Methods and Results: Chronic myocardial ischemia was induced using a minimally invasive model in 23 landrace pigs. Upon demonstration of heart failure, 10 animals were treated with liposome-mediated iNOS-gene-transfer by local intramyocardial injection and 13 animals received a sham procedure to serve as control. The efficacy of this iNOS-gene-…
A pheromone-binding protein from the cockroach Leucophaea maderae: cloning, expression and pheromone binding
2003
0264-6021 (Print) Journal Article; Odorant-binding proteins (OBPs) are thought to transport volatile compounds from air to their receptors through the sensillary lymph. In this protein family, the subgroup of pheromone-binding proteins (PBPs) is specifically tuned to the perception of the sexual pheromone. To date, the description of OBPs has been restricted to Endopterygota and Paraneoptera. Their expression in Orthopteroid has been hypothesized, but no evidence of OBP has been produced in this assemblage to date. In the present study, we describe the first OBP from a Dictyopteran insect that belongs to the cockroach Leucophaea maderae. The PBP of L. maderae (PBPLma) shares all the hallmar…