Trypanosoma cruzi adenylate kinases: characterization and cloning.

PEREIRA, CLAUDIO; BOUVIER, LEÓN ALBERTO; ALONSO, GUILLERMO; IVALDI, SOLEDAD; TORRES, HECTOR; FLAWIA, MIRTHA

Cordoba, Argentina

Congreso; XXXVIII Reunión Anual de la Sociedad Argentina de Investigaciones en Bioquímica y Biología Molecular ? SAIB; 2002

Adenylate kinases are functional conserved enzymes distributed throughout the animal and vegetal kingdoms. These enzymes catalyze the formation of ATP and AMP from two molecules of ADP, thus buffering the cellular energy charge. In trypanosomatids adenylate kinase activities were previously described in Trypanosoma brucei and Phytomonas sp. Herein, we measured an adenylate kinase activity in Trypanosoma cruzi epimastigote cells extracts. The enzyme activity was detected in the soluble and particulate fractions. Preliminary, the kinetic parameters were determined using the soluble fraction, the Km value was 2.1 mM. Adenylate kinases genes were cloned using RT-PCT, "Jumping PCR" and screening of a T. cruzi genomic library. Using these techniques two open reading frames were obtained, probably coding for enzyme isoforms. TcAdeKl and TcAdeK2 sequences have 789 and 687 base pairs corresponding to predicted polypeptides of 262 and 229 amino acids with molecular weights of 30 and 26 kDa respectively. The amino acid sequences show the characteristic consensus domains of the adenylate kinase family, including the P-loop.