Identification of potential Leishmania infantum sirtuin inhibitors

Abstract

Leishmaniasis are caused by different species of Leishmania spp. The disease has a clinical spectrum ranging from cutaneous and mucocutaneous lesions to visceral lesions. During its life cycle, Leishmania sp. transit between invertebrate and vertebrate hosts, facing different environmental changes, which require rapid adaptations of the parasite for its survival. Post- translational modifications, such as acetylation and phosphorylation, have been implicate in the regulation of several cellular processes. Our group recently described the acetylome of promastigote, metacyclic and amastigote forms of Leishmania mexicana, and found 336 differentially lysine acetylated sites (K-ac) in 253 proteins of procyclic; 550 K-ac in 304 proteins in the metacyclic and 349 K-ac in 225 proteins in the amastigote form. Knowing that protein acetylation levels seems to play an important role in the regulatory mechanisms of Leishmania sp. among its evolutionary forms, this project aims to explore the potential of lysine deacetylases, sirtuins, from L. infantum for the identification/validation of new inhibitors of these enzymes. Thus, we intend to: i) clone the LiSir2rp1, LiSir2rp2 and LiSir2rp3 genes in bacteria protein expression vectors; ii) to express and purify the heterologous proteins LiSir2rp1, LiSir2rp2 and LiSir2rp3; iii) to evaluate the effect of the deacetylation activity of LiSir2rp1, LiSir2rp2 and LiSir2rp3 proteins in in vitro assays; iv) to test sirtuin inhibitors in deacetylation inhibition assays using proteins LiSir2rp1, LiSir2rp2 and LiSir2rp3. Thus, we hope with this project to contribute to the validation of sirtuins as potential chemotherapy targets and for the development of new and more specific inhibitors of L. infantum enzymes.