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Surface Binding (surface + binding)
Selected AbstractsReversible and Noncompetitive Inhibition of ,-Tryptase by Protein Surface Binding of Tetravalent Peptide Ligands Identified from a Combinatorial Split,Mix Library,ANGEWANDTE CHEMIE, Issue 24 2010Peter Molekulare Stöpsel: Das On-Bead-Screening einer kombinatorischen Bibliothek von 216 vierarmigen Oligopeptiden lieferte hoch spezifische, nichtkompetitive Inhibitoren der Serinprotease ,-Tryptase mit nanomolarer Affinität. Die Liganden binden sehr wahrscheinlich an die Proteinoberfläche und wirken als molekulare ,Stöpsel", indem sie den Zugang zu den aktiven Zentren blockieren, die sich im Innern einer zentralen Kavität befinden (siehe Bild). [source] Enzyme-Mediated Deposition of a TiO2 Coating onto Biofunctionalized WS2 Chalcogenide Nanotubes,ADVANCED FUNCTIONAL MATERIALS, Issue 2 2009Muhammad Nawaz Tahir Abstract A chemically specific and facile method for the biofunctionalization of WS2 nanotubes (NT-WS2) is reported. The covalent modification strategy is based on the affinity of the nitrilotriacetic acid (NTA) side chain, which serves as a ligand for the surface binding to NT-WS2 and simultaneously as an anchor group for the binding of His-tagged proteins to the polymer backbone. The polymer functionalized WS2 nanotubes can be solubilized either in water or organic solvents; they are stable for at least one week. The probes were characterized by FT-IR and UV-vis spectroscopy. The immobilization of silicatein, a hydrolytic protein encountered in marine sponges, was visualized by scanning force microscopy (SFM) and confocal laser scanning microscopy (CLSM). The formation of the biotitania coating mediated by the immobilized silicatein onto the surface was characterized by scanning electron microscopy (SEM), and transmission electron microscopy (TEM). [source] The contribution of both oxygen and nitrogen intermediates to the intracellular killing mechanisms of C1q-opsonized Listeria monocytogenes by the macrophage-like IC-21 cell lineIMMUNOLOGY, Issue 1 2000C. Álvarez-Domínguez Summary Listeria monocytogenes is a facultative intracellular pathogen which is internalized by host mammalian cells upon binding to their surface. Further listerial growth occurs in the cytosol after escape from the phagosomal,endosomal compartment. We have previously reported that C1q is able to potentiate L. monocytogenes phagocytosis upon bacterial opsonization by ingestion through C1q-binding structures. In this report, we analysed the post-phagocytic events upon internalization of C1q-opsonized L. monocytogenes and found an induction of macrophage (M,)-like IC-21 cell bactericidal mechanisms displayed by the production of oxygen and nitrogen metabolites. Both types of molecules are effective in L. monocytogenes killing. Further analysis of the cellular responses promoted by interaction of C1q with its surface binding structures, leads us to consider C1q as a collaborative molecule involved in M, activation. Upon interaction with surface binding structures, C1q was able to trigger and/or amplify the production of reactive oxygen and nitrogen intermediates induced by stimuli such as interferon-, and L. monocytogenes phagocytosis. [source] Differential effect of materials for surface hemostasis on red blood cell morphologyMICROSCOPY RESEARCH AND TECHNIQUE, Issue 10 2008Carr J. Smith Abstract The design of devices for surface (topical) hemostasis has been based on maximizing activation of platelets and accelerating coagulation pathways. The studies reported herein examine another aspect of blood contact with topical hemostasis materials, i.e., surface binding of red blood cells (RBCs) and related alterations in RBC morphology. Whole blood was allowed to contact poly- N -acetyl glucosamine (pGlcNAc) containing materials: pGlcNAc nanofibers with parallel polymer alignment (,-pGlcNAc), chitin, and chitosan. The effect on RBC morphology and function via contact with the artificial surfaces on the cell's morphology was examined with scanning and transmission electron microscopy (TEM). ,-pGlcNAc was found to densely bind RBCs and induce a stomatocytic-like morphology. Chitin and chitosan also bound RBCs, but with approximately 10-fold lower levels and with less distinct general morphologies. ,-pGlcNAc is thus unique in the nature of its interaction with RBCs. These studies indicate that the differential ability of various materials to bind and alter the morphology of RBCs at the artificial surface interface with blood is an important consideration in the design of devices for surface hemostasis. Microsc. Res. Tech., 2008. © 2008 Wiley-Liss, Inc. [source] The action of Lambert,Eaton myasthenic syndrome immunoglobulin G on cloned human voltage-gated calcium channelsMUSCLE AND NERVE, Issue 5 2002Ashwin Pinto MRCP, DPhil Abstract In the Lambert,Eaton myasthenic syndrome (LEMS), immunoglobulin G (IgG) autoantibodies to presynaptic voltage-gated calcium channels (VGCCs) at the neuromuscular junction lead to a reduction in nerve-evoked release of neurotransmitter and muscle weakness. We have examined the action of LEMS IgGs on cloned human VGCCs stably expressed in transfected human embryonic kidney (HEK293) cell lines: 10,13 (,1A-2, ,2b,, ,4a) and C2D7 (,1B-1 , ,2b,, ,1b). All LEMS IgGs studied showed surface binding to [125I]-,-CTx-MVIIC-labeled VGCCs in the ,1A cell line and two of six IgGs showed surface binding to [125I]-,-CTx-GVIA-labeled VGCCs in the ,1B cell line. We next studied the effect of LEMS IgGs (2 mg/ml) on whole-cell calcium currents in the ,1A and ,1B cell lines. Overnight treatment of ,1A (10,13) cells with LEMS IgGs led to a significant reduction in peak current density without alteration of the current,voltage relationship or the voltage dependence of steady-state inactivation. In contrast, LEMS IgGs did not reduce peak current density in the ,1B cell line. Overall these data demonstrate the specificity of LEMS IgGs for the ,1A cell line and suggest that LEMS IgGs bind to and downregulate VGCCs in this cell line. Although several LEMS IgGs can be shown to bind to the ,1B (C2D7) cell line, no functional effects were seen on this channel. © 2002 Wiley Periodicals, Inc. Muscle Nerve 25: 000,000, 2002 [source] The nuclear autoantigen CENP-B displays cytokine-like activities toward vascular smooth muscle cellsARTHRITIS & RHEUMATISM, Issue 11 2007Geneviève Robitaille Objective A growing number of intracellular autoantigenic polypeptides have been found to play a second biologic role when they are present in the extracellular medium. We undertook this study to determine whether the CENP-B nuclear autoantigen could be added to this set of bifunctional molecules. Methods Purified CENP-B or CENP-B released from apoptotic cells was tested for surface binding to a number of human cell types by cell-based enzyme-linked immunosorbent assay, flow cytometry, and indirect immunofluorescence. The biologic effects of CENP-B on the migration, interleukin secretion, and signaling pathways of its specific target cells were evaluated. Results CENP-B was found to bind specifically to the surface of human pulmonary artery smooth muscle cells (SMCs) and not to fibroblasts or endothelial cells (ECs). Furthermore, CENP-B bound preferentially to SMCs of the contractile type rather than to SMCs of the synthetic type. Binding of CENP-B to SMCs stimulated their migration during in vitro wound healing assays, as well as their secretion of interleukins 6 and 8. The mechanism by which CENP-B mediated these effects involved the focal adhesion kinase, Src, ERK-1/2, and p38 MAPK pathways. Finally, CENP-B released from apoptotic ECs was found to bind to SMCs, thus indicating a plausible in vivo source of extracellular CENP-B. Conclusion These novel biologic roles of the nuclear autoantigen CENP-B open up a new perspective for studying the pathogenic role of anti,CENP-B autoantibodies. [source] | ||||||||||