Search results for "recombinant"
showing 10 items of 1150 documents
Single Molecule Spectroscopy of Oriented Recombinant Trimeric Light Harvesting Complexes of Higher Plants
2002
The bleaching dynamics of reconstituted single light-harvesting chlorophyll a/b investigated. The complexes containing one histidine6 tag per monomeric subunit were immobilised predominantly in a defined orientation with their symmetry axis perpendicular to a Ni-ion-containing surface allowing for the first time the examination of single LHCIIb in an aqueous environment. Most complexes exhibit photobleaching in one step, indicating coupling between the monomeric subunits leading to an energy transfer between adjacent subunits. Differences in bleaching behaviour between these and previous observations with single LHCIIb are discussed.
INFγ stimulates arginine transport through system y+L in human monocytes
2004
Freshly isolated human monocytes transport L-arginine mostly through a sodium independent, NEM insensitive pathway inhibited by L-leucine in the presence, but not in the absence of sodium. Interferon-gamma (IFNgamma) stimulates this pathway, identifiable with system y+L, and markedly enhances the expression of SLC7A7, the gene that encodes for system y+L subunit y+LAT1, but not of SLC7A6, that codes for the alternative subunit y+LAT2. System y+ plays a minor role in arginine uptake by monocytes and the expression of system y+-related genes, SLC7A1 and SLC7A2, is not changed by IFNgamma. These results demonstrate that system y+L is sensitive to IFNgamma.
Enzyme replacement therapy for mucopolysaccharidosis VI: evaluation of long-term pulmonary function in patients treated with recombinant human N-acet…
2010
Pulmonary function is impaired in untreated mucopolysaccharidosis type VI (MPS VI). Pulmonary function was studied in patients during long-term enzyme replacement therapy (ERT) with recombinant human arylsulfatase B (rhASB; rhN-acetylgalactosamine 4-sulfatase). Pulmonary function tests prior to and for up to 240 weeks of weekly infusions of rhASB at 1 mg/kg were completed in 56 patients during Phase 1/2, Phase 2, Phase 3 and Phase 3 Extension trials of rhASB and the Survey Study. Forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1) and, in a subset of patients, maximum voluntary ventilation (MVV), were analyzed as absolute volume in liters. FEV1 and FVC showed little change f…
Receptor phosphorylation does not mediate cross talk between muscarinic M(3) and bradykinin B(2) receptors.
1999
This study examined cross talk between phospholipase C-coupled muscarinic M3and bradykinin B2receptors coexpressed in Chinese hamster ovary (CHO) cells. Agonists of either receptor enhanced phosphoinositide signaling (which rapidly desensitized) and caused protein kinase C (PKC)-independent, homologous receptor phosphorylation. Muscarinic M3but not bradykinin B2receptors were also phosphorylated after phorbol ester activation of PKC. Consistent with this, muscarinic M3receptors were phosphorylated in a PKC-dependent fashion after bradykinin B2receptor activation, but muscarinic M3receptor activation did not influence bradykinin B2receptor phosphorylation. Despite heterologous phosphorylatio…
Clathrin-mediated constitutive endocytosis of PIN auxin efflux carriers in Arabidopsis.
2007
SummaryEndocytosis is an essential process by which eukaryotic cells internalize exogenous material or regulate signaling at the cell surface [1]. Different endocytic pathways are well established in yeast and animals; prominent among them is clathrin-dependent endocytosis [2, 3]. In plants, endocytosis is poorly defined, and no molecular mechanism for cargo internalization has been demonstrated so far [4, 5], although the internalization of receptor-ligand complexes at the plant plasma membrane has recently been shown [6]. Here we demonstrate by means of a green-to-red photoconvertible fluorescent reporter, EosFP [7], the constitutive endocytosis of PIN auxin efflux carriers [8] and their …
Autoimmunity seen through the SEREX-scope.
2003
Autoantibodies can be detected in autoimmune diseases with a long prodromal phase and may serve as early indicators of disease activity. Autoantibody-based screening methods are therefore potent tools for the identification of target antigens. The SEREX method (serological identification of antigens by recombinant expression cloning) has been developed for the serological definition of immunogenic tumor antigens. Recent studies indicate that the SEREX approach may also be utilized for the analysis of complex immune responses involved in autoimmune diseases.
Delineation of the catalytic domain of Clostridium difficile toxin B-10463 to an enzymatically active N-terminal 467 amino acid fragment.
2006
Abstract In an attempt to directly approach the postulated toxic domain of Clostridium difficile 's TcdB-10463, eight subclones of different size and locations in the N-terminal third of the toxin were generated. Expression of these toxin fragments was checked in Western blots and the enzymatic activity of the expressed proteins was analyzed by glucosylating Ras related small GTP-binding proteins. Two polypeptides of 875 aa (TcdBc1–3) and 557 aa (TcdBc1-H) glucosylated their targets Rho, Rac and Cdc42 with the same activity and specificity as the holotoxin. In comparison 516 aa (TcdBc1-N) and 467 aa (TcdBc1-A) protein fragments exhibited highly reduced activity, while Tcdc1 and TcdB2–3 (aa …
Bioencapsulation of living bacteria (Escherichia coli) with poly(silicate) after transformation with silicatein-α gene
2007
Bioencapsulation is an intriguing way to immobilize biological materials, including cells, in silica, metal-oxides or hybrid sol-gel polymers. Until now only the sol-gel precursor technology was utilized to immobilize bacteria or yeast cells in silica. With the discovery of silicatein, an enzyme from demosponges that catalyzes the formation of poly(silicate), it became possible to synthesize poly(silicate) under physiological (ambient) conditions. Here we show that Escherichia coli can be transformed with the silicatein gene, its expression level in the presence of isopropyl beta-D-thiogalactopyranoside (IPTG) can be efficiently intensified by co-incubation with silicic acid. This effect co…
Purification and analysis of polyhistidine-tagged human parvovirus B19 VP1 and VP2 expressed in insect cells
2008
Human parvovirus B19 is an autonomously replicating human pathogen with a specific tropism for human erythroid progenitor cells. There is an interest in producing empty nucleocapsids of B19 as they can be used as tools in molecular biology and diagnostics. Native B19 virus particles are formed from two structural viral proteins, VP1 and VP2. The VP2 protein alone is able to self assemble and consequently form virus-like particles (VLPs) in heterologous expression systems. Purification of recombinant VLPs has been conducted using various traditional methods. These include laborious and time-consuming, e.g. cesium chloride or sucrose gradient ultracentrifugation steps, allowing limited workin…
Generation of lentivirus vectors using recombinant baculoviruses
2008
In spite of advances in conventional four-plasmid transient transfection methods and development of inducible stable production cell lines, production of replication-defective lentiviral vectors in clinical scale has been challenging. Baculovirus technology offers an alternative to scalable virus production as a result of fast and easy production of baculoviruses, efficient transduction of mammalian cells and safety of the baculoviruses. As a first step toward scalable lentiviral production system, we have constructed four recombinant baculoviruses: the BAC-transfer virus expresses green fluorescent protein (GFP) as a transgene and BAC-gag-pol, BAC-vesicular stomatitis virus glycoprotein G …