The tyrosine aminotransferase from Trypanosoma rangeli: sequence and genomic characterization

Fil: Bontempi, Esteban. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Parasitología; Argentina.Fil: Garcia, G. A. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Parasitología; Argentina.Fil: Buschiazzo, A. Instituto de Investigaciones Biotecnológicas, Universidad Nacional de Gral. San Martín, INTI; Argentina.Fil: Henriksson, J. Department of Medical Genetics and Pathology, Uppsala University, Suecia.Fil: Pravia, Carlos. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Parasitología; Argentina.Fil: Ruiz, Andrés Mariano. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Parasitología; Argentina.Fil: Pettersson, Ulf. Department of Medical Genetics and Pathology, Uppsala University; Suecia.Fil: Pszenny, Viviana. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Parasitología; Argentina.The complete sequence and genomic characterization of the tyrosine aminotransferase (TAT) gene from Trypanosoma rangeli is reported. The gene was found to be organized in a tandem multicopy gene array. A homologous mRNA species (2.5 kb) was identified in the epimastigote form of the parasite. From the deduced amino acid sequence, the gene encodes a protein of 420 amino acids with a predicted molecular mass of 46.4 kDa and a theoretical pI of 6.23. A high sequence identity was found with the Trypanosoma cruzi, human and rat enzymes. All the essential residues for TAT enzymatic activity are conserved, as well as a pyridoxal-phosphate attachment site typical of class-I aminotransferases. The recombinant enzyme was recognized by a monoclonal antibody against the T. cruzi enzyme. Additionally, the recombinant protein showed enzymatic activity when incubated with L-tyrosine and 2-oxoglutaric acid as substrates