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Display System (display + system)
Kinds of Display System Selected AbstractsDevelopment of Novel Yeast Cell Surface Display System for Homo-oligomeric Protein by Coexpression of Native and Anchored SubunitsBIOTECHNOLOGY PROGRESS, Issue 4 2006Hirotaka Furukawa Streptavidin derived from Streptomyces avidinii was displayed on the cell surface of the yeast Saccharomyces cerevisiae by cell-surface engineering using two types of plasmid for the expression of a native subunit and an anchored subunit fused with the C-terminus of 318 amino acids of Flo1p containing a glycosylphosphatidylinositol anchor attachment signal. The displayed streptavidin had the binding ability for biotinylated compounds. This was confirmed by fluorescence microscopy after the adsorption of yeast cells displaying streptavidin and biotinylated fluorescein isothiocyanate. On the other hand, streptavidin produced by cells harboring only the plasmid for the expression of the anchored subunit showed a very low binding activity for biotinylated compounds. Cells displaying streptavidin may constitute novel whole-cell affinity adsorbents widely used for immunoassay and biosensing. This coexpression method will ensure that proteins, such as homo- and hetero-oligomeric proteins, are displayed on the cell surface in an active form. [source] Display Plasticity in Response to a Robotic Lizard: Signal Matching or Song Sharing in Lizards?ETHOLOGY, Issue 10 2006C. Brian Smith Many territorial songbirds alter the structure of their songs after listening to and interacting repeatedly with the same neighbors. Here, we use a robotic lizard to test for similar learned changes in signal structure in male Sagebrush lizards, Sceloporus graciosus. Subjects were exposed to two types of headbob displays (species-typical and unusual) both in short-term tests and in repeated exposures for 10 d. We found no evidence for immediate changes in signal structure to match a particular opponent (signal matching) or long-term changes after repeated exposure (,song' sharing). If anything, the lizards' displays became less like that of the robotic stimulus over time. Further tests of other taxa are needed to identify the evolutionary forces that lead to these forms of behavioral plasticity and to determine whether song sharing and signal matching are unique characteristic of songbirds. Lizards also became more agitated and produced more highly aggressive displays of their own when confronted with headbob displays that violated the basic syntactic structure of their display system, confirming that they were paying attention to subtle differences in display structure despite the artificial nature of the treatments. Thus, our study also adds to the growing evidence supporting the use of robotic playbacks to study animal communication. [source] The role of interface framework residues in determining antibody VH/VL interaction strength and antigen-binding affinityFEBS JOURNAL, Issue 10 2006Kenji Masuda While many antibodies with strong antigen-binding affinity have stable variable regions with a strong antibody heavy chain variable region fragment (VH)/antibody light chain variable region fragment (VL) interaction, the anti-lysozyme IgG HyHEL-10 has a fairly strong affinity, yet a very weak VH/VL interaction strength, in the absence of antigen. To investigate the possible relationship between antigen-binding affinity and VH/VL interaction strength, a novel phage display system that can switch two display modes was employed. We focused on the two framework region 2 regions of the HyHEL-10 VH and VL, facing each other at the domain interface, and a combinatorial library was made in which each framework region 2 residue was mixed with that of D1.3, which has a far stronger VH/VL interaction. The phagemid library, encoding VH gene 7 and VL amber codon gene 9, was used to transform TG-1 (sup+), and the phages displaying functional variable regions were selected. The selected phages were then used to infect a nonsuppressing strain, and the culture supernatant containing VH -displaying phages and soluble VL fragment was used to evaluate the VH/VL interaction strength. The results clearly showed the existence of a key framework region 2 residue (H39) that strongly affects VH/VL interaction strength, and a marked positive correlation between the antigen-binding affinity and the VH/VL interaction, especially in the presence of a set of particular VL residues. The effect of the H39 mutation on the wild-type variable region was also confirmed by a SPR biosensor as a several-fold increase in antigen-binding affinity owing to an increased association rate, while a slight decrease was observed for the single-chain variable region. [source] Enriching spaces in practice-based education to support collaboration while mobile: the case of teacher educationJOURNAL OF COMPUTER ASSISTED LEARNING, Issue 4 2007E.M. Morken Abstract Practice-based education is gaining a growing popularity in fields as diverse as, for example, software engineering, pedagogy and medical studies. In practice-based education learning takes place across different learning arenas and requires cooperation among all the actors involved in the learning process. However, mobility of students across these arenas impact deeply on cooperation patterns, and therefore on the learning process. In this paper we investigate the usage of shared display systems to promote cooperation among students in practice-based education. Our focus is on teacher education and the paper is based on our experiences with the teacher education programme at our university. Based on our observations of students out in practice, we discuss the importance of common spaces and the role of bulletin boards of different types. We then define high-level requirements for a shared display system to support practice-based education and we illustrate the main concepts with a demonstrator. Strengths and weaknesses of our approach are pointed out through an evaluation of the demonstrator. [source] A novel mammalian display system for the selection of protein,protein interactions by decoy receptor engagementJOURNAL OF MOLECULAR RECOGNITION, Issue 4 2004Peter Ellmark Abstract The emerging field of proteomics has created a need for new high-throughput methodologies for the analysis of gene products. An attractive approach is to develop systems that allow for clonal selection of interacting protein pairs from large molecular libraries. In this study, we have characterized a novel approach for identification and selection of protein,protein interactions, denoted SPIRE (selection of protein interactions by receptor engagement), which is based on a mammalian expression system. We have demonstrated proof of concept by creating a general plasma membrane bound decoy receptor, by displaying a protein or a peptide genetically fused to a trunctated version of the CD40 molecule. When this decoy receptor is engaged by a ligand to the displayed protein/peptide, the receptor expressing cell is rescued from apoptosis. To design a high-throughput system with a highly parallel capacity, we utilized the B cell line WEHI-231, as carrier of the decoy receptor. One specific peptide-displaying cell could be identified and amplified, based on a specific receptor engagement, in a background of 12,500 wild-type cells after four selections. This demonstrates that the approach may serve as a tool in post-genomic research for identifying protein,protein interactions, without prior knowledge of either component. Copyright © 2004 John Wiley & Sons, Ltd. [source] Development of a LytE-based high-density surface display system in Bacillus subtilisMICROBIAL BIOTECHNOLOGY, Issue 2 2008Chyi-Liang Chen Summary The three N-terminal, tandemly arranged LysM motifs from a Bacillus subtilis cell wall hydrolase, LytE, formed a cell wall-binding module. This module, designated CWBMLytE, was demonstrated to have tight cell wall-binding capability and could recognize two classes of cell wall binding sites with fivefold difference in affinity. The lower-affinity sites were approximately three times more abundant. Fusion proteins with ,-lactamase attached to either the N- or C-terminal end of CWBMLytE showed lower cell wall-binding affinity. The number of the wall-bound fusion proteins was less than that of CWBMLytE. These effects were less dramatic with CWBMLytE at the N-terminal end of the fusion. Both CWBMLytE and ,-lactamase were essentially functional whether they were at the N- or C-terminal end of the fusion. In the optimal case, 1.2 × 107 molecules could be displayed per cell. As cells overproducing CWBMLytE and its fusions formed filamentous cells (with an average of nine individual cells per filamentous cell), 1.1 × 108,-lactamase molecules could be displayed per filamentous cell. Overproduced CWBMLytE and its fusions were distributed on the entire cell surface. Surface exposure and accessibility of these proteins were confirmed by immunofluorescence microscopy. [source] Nano-sized bacterial magnetic particles displaying pyruvate phosphate dikinase for pyrosequencingBIOTECHNOLOGY & BIOENGINEERING, Issue 1 2009Tomoko Yoshino Abstract There is a high demand for inexpensive and high-throughput DNA sequencing technologies in molecular biology and applied biosciences. In this study, novel nano-sized magnetic particles displaying enzymes for pyrosequencing, a rather novel bioluminometric DNA sequencing method based on the sequencing-by-synthesis principle by employing a cascade of several enzymatic reactions, was developed. A highly thermostable enzyme, pyruvate phosphate dikinase (PPDK) which converts PPi to ATP was successfully expressed onto bacterial magnetic particles (BacMPs) using a novel protein display system of Magnetospirillum magneticum AMB-1. The enzymatic stability of BacMPs displaying PPDK (PPDK-BacMPs) to pH and temperature was evaluated and its broad range of properties was shown. Subsequently, PPDK-BacMPs were applied in pyrosequencing and a target oligonucleotide was successfully sequenced. The PPDK enzyme displayed on BacMPs was shown to be recyclable in each sequence reaction as they can be manipulated by magnetic force. It was concluded that nano-sized PPDK-BacMPs are useful for the scale down of pyrosequencing reaction volumes, thus, permitting high-throughput. The recycling of enzymes was also shown to be promising and applicable for the development of an inexpensive DNA sequencing at a low running cost. Biotechnol. Bioeng. 2009;103: 130,137. © 2008 Wiley Periodicals, Inc. [source] A Covalent Chemical Genotype,Phenotype Linkage for in vitro Protein EvolutionCHEMBIOCHEM, Issue 18 2007Viktor Stein Display model. Proteins fused to O6 -alkylguanine alkyltransferase (AGT) were expressed in vitro and conjugated to their coding DNA via O6 -benzylguanine, a suicide inhibitor of AGT. The potential of this display system is demonstrated for several proteins in model selection experiments. Enrichments of up to 100-fold and DNA recovery rates of up to 2.4,% are achieved per round of selection. [source] An experimental analysis of decision channeling by restrictive information displayJOURNAL OF BEHAVIORAL DECISION MAKING, Issue 5 2002Manouchehr TabatabaeiArticle first published online: 15 OCT 200 Abstract This study focuses on the effect of restrictive information display on decision performance. Specifically the study examines whether two-channeled and one non-channeled computerized information display systems result in significant differences in decision accuracy. The two-channeled information display systems are designed to encourage two general information processing patterns commonly observed in the experimental literature examining multi-alternative, multi-attribute choice decisions: information processing by alternative and information processing by attribute. An information display program was developed which used restrictive information display to operationalize the channeled versus non-channeled manipulation. Channeling was implemented either by displaying information only by alternative or by displaying information only by attribute. The task was an operations scheduling problem that subjects completed under three levels of time pressure. The results indicate statistically significant effects on decision accuracy for both the type of information display and time pressure manipulations. The highest decision accuracy was observed when information was displayed by alternative and when subjects were under highest levels of time pressure. Copyright © 2002 John Wiley & Sons, Ltd. [source] Enriching spaces in practice-based education to support collaboration while mobile: the case of teacher educationJOURNAL OF COMPUTER ASSISTED LEARNING, Issue 4 2007E.M. Morken Abstract Practice-based education is gaining a growing popularity in fields as diverse as, for example, software engineering, pedagogy and medical studies. In practice-based education learning takes place across different learning arenas and requires cooperation among all the actors involved in the learning process. However, mobility of students across these arenas impact deeply on cooperation patterns, and therefore on the learning process. In this paper we investigate the usage of shared display systems to promote cooperation among students in practice-based education. Our focus is on teacher education and the paper is based on our experiences with the teacher education programme at our university. Based on our observations of students out in practice, we discuss the importance of common spaces and the role of bulletin boards of different types. We then define high-level requirements for a shared display system to support practice-based education and we illustrate the main concepts with a demonstrator. Strengths and weaknesses of our approach are pointed out through an evaluation of the demonstrator. [source] Synthetic approaches to 3H -naphtho[2,1- b]pyrans and 2,3-dihydro-1H -naphtho[2,1- b]pyransJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2009Amitabh Jha Naphtho[2,1- b]pyran nuclei are prevalent in natural products with significant biological and medicinal properties. 3,3-Disubstituted 3H -naphtho[2,1 -b]pyrans are photochromic and find use in electronic display systems, ophthalmic lenses, optical switches, and temporary or permanent memories. Of the various possible structural isomers of naphthopyran framework, this review is an account of reported synthetic procedures to produce 3H -naphtho[2,1-b]pyrans and their dihydro analogs, 2,3-dihydro-1H -naphtho[2,1 -b]pyrans. The advantages and disadvantages of each procedure in terms of yields, complexity, formation of side-products, use of uncommon/expensive reagents, etc., are also described. J. Heterocyclic Chem., (2009). [source] Conduct of operations: A control system for your most important safety componentPROCESS SAFETY PROGRESS, Issue 1 2000Paul Haas Instrumentation and control engineers go to great lengths to ensure availability and operability of control and information display systems for process system operation, especially for safety systems. It is critically important to maintain equipment performance within the bounds of safe operation. The most crucial safety components in your facility are the human beings controlling, maintaining, monitoring, and managing the process and equipment. Have you ever given much thought to the control systems operated by humans in your facility? [source] Surface-exposed expression of Edwardsiella tarda EseB in live attenuated Vibrio anguillarum based on novel surface display systemsAQUACULTURE RESEARCH, Issue 13 2009Qiyao Wang Abstract Live, attenuated Vibrio anguillarum strains can serve as vectors for the delivery of heterologous antigens for development of multivalent recombinant vaccines. Based on the outer membrane anchoring elements of V. anguillarum, we have previously constructed several efficient surface display systems Lpp-Omporf1, Lpp-OmpU, Lpp-Omp26La, Wza-Omporf1, Wza-OmpU and Wza-Omp26La. In this study, with these constructed surface display systems, a putative antigen protein EseB from pathogenic Edwardsiella tarda was successfully expressed on the surface of an attenuated V. anguillarum strain to get multivalent vaccine candidates. Further immune protection evaluation in zebra fish (Danio rerio) demonstrated that the V. anguillarum EseB-display strain AV/pW-26La-B could trigger full protection against V. anguillarum infection and early protection against E. tarda infection in the immunized fish. These results suggest that surface display of heterologous protective antigens in attenuated V. anguillarum could be used as a tool to develop potential V. anguillarum vector vaccine. [source] | |||||||||||||