Energy metabolism in trypanosomes: the putative role of the ATP regeneration systems by phosphotransferases.

BOUVIER, LEÓN ALBERTO; MIRANDA, MARIANA; CANEPA, GASPAR; PEREIRA, CLAUDIO

Rosarion, Argentina

Encuentro; XX Reunión de Protozoología y Enfermedades Parasitarias; 2004

Maintenance of energy homeostasis is a crucial cellular process. Two enzymes with core roles in maintaining energy balance are adenylate kinase (phosphotransferase with a phosphate group as acceptor) and arginine kinase (phosphotransferase with a nitrogenous group as acceptor). Arginine kinase activity provides a spatial and temporal energy buffer that can be readily mobilized during cellular stress, whilst in mammalian cells the former enzyme is suggested to communicate energetic signals between different cellular compartments. Adenylate kinase is involved in the homeostasis of adenine nucleotides by interconvertion of constituents of the adenine nucleotide pool, including ATP synthesis from ADP. Here, we discuss first, a comparative genomic analysis of the arginine kinase gene loci in different protozoan parasites such as Trypanosoma cruzi, Trypanosoma brucei, Leishmania major and Leishmania infantum. Secondly, the effect of silencing the expression of all three isoform genes in procyclic Trypanosoma brucei by RNA interference ir order to analyze the role of these enzymes in vivo. At last, the identification and characterization of at least seven distinct adenylale kinases in Trypanosome cruzi, more than any other organism for which significant genome sequence is available, including mammals and several other eukaryotic microbes.