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

MIRANDA, MARIANA; BOUVIER, LEON; CANEPA, GASPAR; PEREIRA, CA

Caxambu

Congreso; XXI Annual Meeting of the Brazilian Society of Protozoology; 2005

Adenylate kinases supply energy routes in cellular energetic homeostasis. In this work we identi¯ed and characterized the adenylate kinase activity in extracts from the °agellated parasite Trypanosoma cruzi. Adenylate kinase speci¯c 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 °agellum, mitochondria, glycosome and cytosol. Surprisingly, an unusual adenlate kinase sequence similar to the nuclear AdK6 (human) was detected in the T. cruziTrypanosoma cruzi. Adenylate kinase speci¯c 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 °agellum, mitochondria, glycosome and cytosol. Surprisingly, an unusual adenlate kinase sequence similar to the nuclear AdK6 (human) was detected in the T. cruziE. 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 °agellum, mitochondria, glycosome and cytosol. Surprisingly, an unusual adenlate kinase sequence similar to the nuclear AdK6 (human) was detected in the T. cruziT. 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.Trypanosoma cruzi.