Template assisted synthesis of organic, inorganic and organic-inorganic hybrid hollow spheres

process & energyMechanical, Maritime and Materials Engineerin

Inorganic Core-Shell-Particles by Wet-Chemical Processes

As can be shown by the rapid development of scientific subjects like microtechnology and nanotechnology, there is a continuous tendency in microstructuring advanced materials. In most cases, the detailed structurization of powdery solids (like precursors for ceramic components or additives for plastics and elastomers) can be advantageously performed on the level of individual particles. The core-shell or microcapsules structure is an example for microstructures at particle dimensions having multiple application potentials. The coating of an original particle (core) by a shell-forming compound results in a partial or complete masking or modifying of the primary chemical, physical or sensoric properties of the core material by those of the shell material. It is of highest priority that the resulting microcapsule exhibits the properties of both core and shell materials, either permanently or time-delayed. The studies presented here aim at inorganic core-shell s ystems suitable as functional filling agents, pigments or powdery ceramic precursors for innovative material applications. The most interesting substances taken into consideration as inorganic coating materials are sparingly soluble or insoluble metal oxides and metal carbonates that can be transformed into oxides by successive calcination steps

COMCAR - Systemkonzept UMTSplus (Universalitaet und Mobilitaet in Telekommunikationsnetzen und -systemen). Teilvorhaben: Bidirektionale, bedarfsgerechte, drahtlose, zuverlaessige Kommunikation von und zu mobilen Objekten Abschlussbericht

Available from TIB Hannover: F03B128+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung und Forschung, Berlin (Germany)DEGerman

Synthesis and Characterization of Cytidine Derivatives that Inhibit the Kinase IspE of the Non-Mevalonate Pathway for Isoprenoid Biosynthesis

The enzymes of the non-mevalonate pathway for isoprenoid biosynthesis are attractive targets for the development of novel drugs against malaria and tuberculosis. This pathway is used exclusively by the corresponding pathogens, but not by humans. A series of water-soluble, cytidine-based inhibitors that were originally designed for the fourth enzyme in the pathway, IspD, were shown to inhibit the subsequent enzyme, the kinase IspE (from Escherichia coli). The binding mode of the inhibitors was verified by co-crystal structure analysis, using Aquifex aeolicus IspE. The crystal structures represent the first reported example of a co-crystal structure of IspE with a synthetic ligand and confirmed that ligand binding affinity originates mainly from the interactions of the nucleobase moiety in the cytidine binding pocket of the enzyme. In contrast, the appended benzimidazole moieties of the ligands adopt various orientations in the active site and establish only poor intermolecular contacts with the protein. Defined binding sites for sulfate ions and glycerol molecules, components in the crystallization buffer, near the well-conserved ATP-binding Gly-rich loop of IspE were observed. The crystal structures of A. aeolicus IspE nicely complement the one from E. coli IspE for use in structure-based design, namely by providing invaluable structural information for the design of inhibitors targeting IspE from Mycobacterium tuberculosis and Plasmodium falciparum. Similar to the enzymes from these pathogens, A. aeolicus IspE directs the OH group of a tyrosine residue into a pocket in the active site. In the E. coli enzyme, on the other hand, this pocket is lined by phenylalanine and has a more pronounced hydrophobic character.