Objetivo - Gain insight into the structure - function relationships in AChE with regard to cholinergic ligands, by combining structural studies on complexes of AChE with representative examples of some important ligand families, with theoretical approaches that would allow relating the structural data to experimentally measured dynamic and thermodynamic properties;- Other important objectives are the development of improved computer aided design tools for protein - drug interactions.Results so far- Crystal structures of 2 complexes of Torpedo californica AChE with Fasciculin, a snake venom toxin, and with a transition state analogue, Huperazine, were solved.- A Laue diffraction pattern was obtained for an orthorhombic crystal of Torpedo AChE, diffracting out to 2.8Å, in 4 msec.- Recombinant AChE was expressed in HEK293 cells, and purified. This material will be used in crystallisation trials.- Automatic procedures were applied to analyse the conformational differences between native Torpedo AChE, and the enzyme structure when complexed to several ligands for which the enzyme-ligand X-ray structure is known. The results suggest that the ligand induced conformational changes are very small and limited primarily to loop regions.- Multiple copy molecular dynamics' simulations and continuum electrostatic calculations were used to map the entry and exit pathways of small cations, anions, and neutral ligands in the active enzyme gorge. The results suggest that the electrostatic potential varies little throughout the gorge region and is not influenced by the large macrodipole displayed by the enzyme as a whole.- This project will combine structural studies by X-ray diffraction with theoretical computer simulations and molecular modelling approaches;- To structure determination of complexes with AChE with ligands of fundamental and toxicological or therapeutic interest by X-ray crystallography;- Analysis of the electrostatic properties of the enzyme active site and its surrounding using atomic and continuum models;- Investigation of the effects of thermal motion and electrostatic field on the diffusion of water and ligands in the active site gorge;- Mapping of binding sites and diffusion pathways of simple ligands in the active site cleft of AChE. Programa(s) IC-ISC C - Activity (Euratom, EEC) on cooperation in science and technology, 1984- Tema(s) Data not available Convocatoria de propuestas Data not available Régimen de financiación CSC - Cost-sharing contracts Coordinador UNIVERSITE LIBRE DE BRUXELLES Aportación de la UE Sin datos Dirección 50,Avenue F.D. Roosevelt 50 1050 BRUXELLES Bélgica Ver en el mapa Coste total Sin datos
