New insights in Trypanosoma cruzi proteomic map: further post-translational modifications and potential drug targets in Y strain epimastigotes

Chagas´ disease is a neglected sickness endemic in Latin America, caused by the protozoa Trypanosoma cruzi. The current treatment for the disease is unsatisfactory, and the development of potent compounds for novel molecular targets is critical. In this framework, proteomics could be a powerful tool in the evaluation of possible candidates for drug intervention. In this work, a two-dimensional electrophoresis (2-DE) and mass spectrometry (MS) approach was employed in T. cruzi epimastigotes (Y strain). Different gel staining protocols (Coomassie Blue, Pro-Q-Diamond and Pro-Q-Emerald) were performed to assess the protein content and possible post-translational modifications of this parasite. Here, 78 most intense spots were identified by Coomassie staining, 22 by Pro-Q-Diamond (phosphoproteins) and 15 by Pro-Q-Emerald (glycoproteins). Compared with the results of other large-scale T. cruzi proteomic studies, 15 novel proteins were identified here using MALDI-TOF/TOF, and 12 of these have not yet been described at the protein level. The predominant localisation and function of the identified proteins was cytosol and protein metabolism, respectively. Regarding the potentially interesting drug targets, 8 proteins presented no similarity to human sequences and promising characteristics for chemotherapy intervention. Our data provides novel insights in the metabolic pathways of T. cruzi, which could aid in the discovery of alternative drugs for Chagas´ disease.