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

BOUVIER LA; MIRANDA MR; CANEPA GE; PEREIRA CA

Rosario

Congreso; XX Reunión Anual de la Sociedad Argentina de Protozoología; 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 interconversion 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 expressing of all three isoform genes in procyclic T. brucei by RNA interference in order to analysis the role of these enzymes in vivo. Al last, the identification and caracterization of at least seven distinct adenylate kinase in Trypanosoma cruzi, more than any other organism for which signifacant genome sequence is a available, including mammals and several other eukaryotic microbes.