Author(s): Azevedo, Clênia dos Santos ; Guido, Bruna Cândido ; Pereira, Jhonata L. ; Nolasco, Diego O. ; Corrêa, Rafael ; Magalhães, Kelly Grace ; Motta, Flávia Nader ; Santana, Jaime Martins de ; Grellier, Philippe ; Bastos, Izabela Marques Dourado
Date: 2017
Origin: Oasisbr
Subject(s): Enzimas; Leishmania; Leishmaniose - tratamento
Deubiquitinating enzymes (DUBs) play an important role in regulating a variety of eukaryotic processes. In this context, exploring the role of deubiquitination in Leishmania infantum could be a promising alternative to search new therapeutic targets for leishmaniasis. Here we present the first characterization of a DUB from L. infantum, otubain (OtuLi), and its localization within parasite. The recombinant OtuLi (rOtuLi) showed improved activity on lysine 48 (K48)-linked over K63-linked tetra-ubiquitin (Ub) and site-directed mutations on amino acids close to the catalytic site (F82) or involved in Ub interaction (L265 and F182) caused structural changes as shown by molecular dynamics, resulting in a reduction or loss of enzyme activity, respectively. Furthermore, rOtuLi stimulates lipid droplet biogenesis (an inflammatory marker) and induces IL-6 and TNF-a secretion in peritoneal macrophages, both proinflammatory cytokines. Our findings suggest that OtuLi is a cytoplasmic enzyme with K48-linked substrate specificity that could play a part in proinflammatory response in stimulated murine macrophages.
