Enolase from Trypanosoma cruzi is inhibited by its interaction with metallocarboxypeptidase-1 and a putative acireductone dioxygenase

Publication date: Available online 10 March 2018 Source:Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics Author(s): E. Quintero-Troconis, N. Buelvas, C. Carrasco-López, M.R. Domingo-Sananes, L. González-González, R. Ramírez-Molina, L. Osorio, A. Lobo-Rojas, A.J. Cáceres, P.A. Michels, H. Acosta, W. Quiñones, J.L. Concepción Purification of enolase (ENO) from the cytosol of Trypanosoma cruzi indicated that it may interact with at least five other proteins. Two of them were identified as metallocarboxypeptidase-1 (TcMCP-1) and a putative acireductone dioxygenase (ARDp). Subcellular localization studies confirmed the presence of ARDp in the cytosol, as is the case for ENO and TcMCP-1. Analysis of the ARDp sequence showed that this protein has two domains, an N-terminal ARD and a C-terminal TRP14 (thioredoxin-related protein) domain. The interactions between ENO, TcMCP-1 and ARDp were confirmed for the natural proteins from the trypanosome (using size-exclusion chromatography and co-immunoprecipitation from a cytosolic fraction) and recombinant forms (using ELISA ligand-binding assay and ENO activity assays). The ELISA ligand-binding assays permitted to verify the optimal physicochemical conditions for the interactions (representative for the physiological conditions) and to determine the affinity constants (Kd): ENO/ARDp: 9.54 ± 0.82 nM, ARDp/ENO 10.05 ± 1.11 nM, and ENO/TcMCP-1: 5.66 ± 0.61 nM). The data also show that the...

Source: Biochimica et Biophysica Acta (BBA) Proteins and Proteomics - March 11, 2018 Category: Biochemistry Source Type: research