An expanded family of adenylate kinases in the protozoan parasite Trypanosoma cruzi

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

Caxambu, Brasil

Congreso; XXI Annual Meeting of the Brazilian Society of Protozoology, XXXII Annual Meeting on Basic Research in Chagas Disease, International Symposium on Vesicle Trafficking in Parasitic Protozoa; 2005

Adenylate kinases supply energy routes in cellular energetic homeostasis. In this work we identified and characterized the adenylate kinase activity in extracts from the flagellated parasite Trypanosoma cruzi. Adenylate kinase specific activity increases continuously during the epimastigote growth curve and is down regulated when other phosphotrans- ferase, arginine kinase, is overexpressed. Two adenylate kinase isoforms named TzAdK1 and TzAdK2 were cloned and functionally expressed in E. coli. Based on the localization data from T. brucei orthologs, TzAdK1 and TzAdK2 are °agellar and mitochondrial isoforms, respectively. We have also cloned and partially characterized four additional adenylate kinase isoforms with a predicted subcellular localization in flagellum, mitochondria, glycosome and cytosol. Surprisingly, an unusual adenlate kinase sequence similar to the nuclear AdK6 (human) was detected in the T. cruzi genome. This work reports the presence of a large number of adenylate kinase isoforms suggesting a coordinated regulation of phosphotransferase-mediated ATP regenerating pathways in the unicellular parasite Trypanosoma cruzi