Sandwich Structures
Mostrando 25-36 de 49 artigos, teses e dissertações.
-
25. Blendas de polipirrol e poli(cloreto de vinila) : propriedades termicas, mecanicas e eletroquimicas
Blends including an intrinsically conductive polymer, polypyrrole or polythiophene, and an insulating polymer, PVC, were prepared. The method used was the oxidative chemical polymerization of the heterocyclic monomers, in the vapor phase, in PVC films impregnated with an oxidant agent (FeCl3). This procedure was efficient for the preparation of blends compos
Publicado em: 1995
-
26. Estudo quantitativo da reatividade de compostos organometalicos de metais de transição
Despite the enormous number of studies of organo-metallic complexas of the sandwich type, many aspects of their chemistry remain to be clarified. These include the mechanisms of the reactions; and the participation of -orbitals in the bonding between the ligand and the central atom. Since reactivity measurements are a powerful tool in chemical investigations
Publicado em: 1977
-
27. Formation of AraC-DNA sandwiches.
With the use of special DNA binding sites, but not the natural aral binding site, the dimeric AraC protein can be forced to make sandwich structures in which two DNA molecules are joined by two AraC protein dimers. Apparently one subunit from each dimer contacts each DNA molecule in an extended structure. These sandwich structures form only in the absence of
-
28. Common features in structures and sequences of sandwich-like proteins
The goal of this work is to define the structural and sequence features common to sandwich-like proteins (SPs), a group of very different proteins now comprising 69 superfamilies in 38 protein folds. Analysis of the arrangements of strands within main sandwich sheets revealed a rigorously defined constraint on the supersecondary substructure that holds true
National Academy of Sciences.
-
29. Betadoublet: de novo design, synthesis, and characterization of a beta-sandwich protein.
How an amino acid sequence encodes the information necessary for a protein to adopt a unique tertiary structure remains unresolved. We are addressing this problem by designing "from scratch" protein molecules that will adopt predetermined three-dimensional structures. Based on this strategy, two identical four-stranded beta-sheets were designed to dimerize a
-
30. Genetic analysis of the leucine heptad repeats of Lac repressor: evidence for a 4-helical bundle.
Gel-filtration experiments indicate that a peptide (P2) composed of the basic region of GCN4 fused to the leucine heptad repeats of Lac repressor forms tetrameric aggregates. Gel-shift experiments were performed to determine the orientation of the helices in the tetrameric P2 aggregate. Sandwich-complex formation of peptide P2 with two DNA fragments containi
-
31. Considerations on the folding topology and evolutionary origin of cadherin domains.
Cell-cell adhesion in zonula adherens and desmosomal junctions is mediated by cadherins, and recent crystal structures of the first domain from murine N-cadherin provide a plausible molecular basis for this adhesive action. A structure-based sequence analysis of this adhesive domain indicates that its fold is common to all extracellular cadherin domains. The
-
32. A novel two-over-two α-helical sandwich fold is characteristic of the truncated hemoglobin family
Small hemoproteins displaying amino acid sequences 20–40 residues shorter than (non-)vertebrate hemoglobins (Hbs) have recently been identified in several pathogenic and non-pathogenic unicellular organisms, and named ‘truncated hemoglobins’ (trHbs). They have been proposed to be involved not only in oxygen transport but also in other biological functi
Oxford University Press.
-
33. Crystal structures of the noncatalytic domains of ADAMTS13 reveal multiple discontinuous exosites for von Willebrand factor
ADAMTS13 specifically cleaves plasma von Willebrand factor (VWF) and thereby controls VWF-mediated platelet thrombus formation. Severe deficiencies in ADAMTS13 can cause life-threatening thrombotic thrombocytopenic purpura. Here, we determined 2 crystal structures of ADAMTS13-DTCS (residues 287–685), an exosite-containing human ADAMTS13 fragment, at 2.6-�
National Academy of Sciences.
-
34. Crystal structure and snapshots along the reaction pathway of a family 51 α-l-arabinofuranosidase
High-resolution crystal structures of α-l-arabinofuranosidase from Geobacillus stearothermophilus T-6, a family 51 glycosidase, are described. The enzyme is a hexamer, and each monomer is organized into two domains: a (β/α)8-barrel and a 12-stranded β sandwich with jelly-roll topology. The structures of the Michaelis complexes with natural and synthetic
Oxford University Press.
-
35. The Prevalence and Nature of Glycan Alterations on Specific Proteins in Pancreatic Cancer Patients Revealed Using Antibody-Lectin Sandwich Arrays*
Changes to the glycan structures of proteins secreted by cancer cells are known to be functionally important and to have potential diagnostic value. However, an exploration of the population variation and prevalence of glycan alterations on specific proteins has been lacking because of limitations in conventional glycobiology methods. Here we report the use
The American Society for Biochemistry and Molecular Biology.
-
36. Crystal Structures of a Poplar Xyloglucan Endotransglycosylase Reveal Details of Transglycosylation Acceptor Binding
Xyloglucan endotransglycosylases (XETs) cleave and religate xyloglucan polymers in plant cell walls via a transglycosylation mechanism. Thus, XET is a key enzyme in all plant processes that require cell wall remodeling. To provide a basis for detailed structure–function studies, the crystal structure of Populus tremula x tremuloides XET16A (PttXET16A), het
American Society of Plant Biologists.