Cholinesterases: Structure, Role, and Inhibition

Acetilkolinesteraza (AChE; E.C. 3.1.1.7) i butirilkolinesteraza (BChE; E.C. 3.1.1.8) enzimi su koji se zbog svoje uloge u organizmu intenzivno istražuju unutar područja biomedicine i toksikologije. Iako strukturno homologni, ovi enzimi razlikuju se prema katalitičkoj aktivnosti, odnosno specifi čnosti prema supstratima koje mogu hidrolizirati te selektivnosti za vezanje mnogih liganada. U ovom radu dan je pregled dosadašnjih istraživanja kolinesteraza i njihovih interakcija s ligandima i inhibitorima te su izdvojene aminokiseline aktivnog mjesta koje sudjeluju u tim interakcijama.Enzymes acetylcholinesterase (AChE; E.C. 3.1.1.7) and butyrylcholinesterase (BChE; E.C. 3.1.1.8) have intensively been investigated in biomedicine and toxicology due to important role in organisms. Even if structurally homologous, they differ in catalytic activity, specificity, for substrates, and selectivity in binding to many ligands. This paper compiles the results of research on cholinesterases and their interactions with ligands and inhibitors, and identifies amino acids of active sites involved in these interactions

SEPARATION AND DOMAIN STRUCTURE OF α + B2 PHASE IN Fe-Al ALLOYS

Le processus de séparation et la structure en domaines des alliages Fe3-εAl1+ε en région biphasée α + B2 ont été recherchés en microscopie électronique. Nous avons observé l'image du fond noir par la réflexion de surstructure B2. Il en résulte que la séparation de phase à côté de la frontière entre α ou B2 et α + B2, procède de la germination et croissance des précipités B2 ou α dans la matrice α ou B2, au lieu que dans la région centrale de la phase α + B2 la séparation procède du développement de la fluctuation périodique locale sur la composition et le degré d'ordre. Dans ce dernier cas, la structure en domaines a montré les caractéristiques de la décomposition spinodale. Le processus inverse α + B2 → B2 dans la région centrale consiste en une diminution de la fluctuation à partir de la frontière entre α et B2.The process of phase separation and the domain structure of Fe3-εAl1+ε in the α + B2 phase region were investigated by means of electron microscopy. The observation by dark field images with B2 superlattice reflection revealed that the phase separation near the phase boundary between α or B2 and α + B2 regions proceeds by nucleation and growth of B2 or α precipitates in α or B2 matrix, correspondingly, whereas in the central region of the α + B2 phase the separation proceeds by development of a local periodic fluctuation in the composition and degree of order. The domain structure in the latter case showed a characteristic feature of spinodal decomposition. The reverse process, α + B2 → B2, in the central region is a diminution of grown-up fluctuation starting from the boundaries between α and B2 domains

A Computational Model of the LGI1 Protein Suggests a Common Binding Site for ADAM Proteins

Mutations of human leucine-rich glioma inactivated (LGI1) gene encoding the epitempin protein cause autosomal dominant temporal lateral epilepsy (ADTLE), a rare familial partial epileptic syndrome. The LGI1 gene seems to have a role on the transmission of neuronal messages but the exact molecular mechanism remains unclear. In contrast to other genes involved in epileptic disorders, epitempin shows no homology with known ion channel genes but contains two domains, composed of repeated structural units, known to mediate protein-protein interactions