Trypanosoma cruzi: multiple nucleoside diphosphate kinase isoforms in a single cell.
Nucleoside diphosphate kinases (NDPKs) are multifunctional enzymes involved mainly in the conservation of nucleotides and deoxynucleotides at intracellular levels. Here we report the characterization of two NDPKs from the protozoan parasite Trypanosoma cruzi, the etiological agent of Chagas disease. TcNDPK1 and TcNDPK2 were biochemically characterized presenting different kinetic parameters and regulation mechanisms. NDPK activity was mainly detected in soluble fractions according to the digitonin extraction technique; however 20% of the activity remains insoluble at digitonin concentrations up to 5 mg ml(-1). TcNDPK1 is a short enzyme isoform, whereas TcNDPK2 is a long one containing a DM10 motif. In addition, two other putative NDPK genes (TcNPDK3 and TcNDPK4) were detected by data mining at the T. cruzi genome database. The large number and diversity of NDPK isoforms are in agreement with those previously observed for other T. cruzi phosphotransferases, such as adenylate kinases.
Laboratorio de Biología Molecular de Trypanosoma cruzi, Instituto de Investigaciones Médicas Alfredo Lanari, Universidad de Buenos Aires and CONICET, Av. Combatientes de Malvinas 3150, 1427 Capital Federal, Buenos Aires, Argentina.
Mariana R
MR
Miranda
Gaspar E
GE
Canepa
León A
LA
Bouvier
Claudio A
CA
Pereira
D000818:Animals; D003001:Cloning, Molecular; D004072:Digitonin; D015971:Gene Expression Regulation, Enzymologic; D007202:Indicators and Reagents; D007527:Isoenzymes / Q000032:analysis / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D051379:Mice; D008807:Mice, Inbred BALB C; D009701:Nucleoside-Diphosphate Kinase / Q000032:analysis* / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D014349:Trypanosoma cruzi / Q000201:enzymology* / Q000235:genetics
D007202:Indicators and Reagents; D007527:Isoenzymes; D009701:Nucleoside-Diphosphate Kinase; D004072:Digitonin