Computational study of substrates and mediators features of lacasses

摘要

Laccases are enzymes of the family of the multicopper oxidases, being widely used for biotechnological applications. The enzyme catalytic cycle consists in the oxidation of the substrate with the concomitant reduction of molecular oxygen to water. In the process the substrate is converted to a free radical, that can oxidize larger substrates acting as a mediator or it can undergo polymerization. Substrate binding is not specific and there is a large diversity of substrates for laccases. Moreover, the binding site shows important differences among diverse species. The goal of the present work is to characterize the laccase binding pocket of different species in order to establish their common pharmacophoric characteristics. For this purpose we have carried out docking studies with a subset of substrates, covering the diversity of substrates using the Glide program. We have also analyze the characteristics of the binding site using diverse probes. We further have rationalized the differential values of Km found among diverse species for a specific substrate. Finally, special attention has been devoted to the binding of the mediator 2,2’-azido-di- (3-ethylbenzothiazoline) -6-sulfonic acid (ABTS), commonly used in industrial processe