Cloning and sequence analysis of the gene encoding pyruvate kinase in Trypanoplasma borelli

Ernest, Isabelle Opperdoes, Frederik [UCL] Michels, Paulus [UCL]

The gene coding for pyruvate kinase in Trypanoplasma borelli has been cloned and characterized. A single gene copy was found with an open reading frame for a polypeptide of 496 amino acids and a molecular mass of 54337. The deduced amino acid sequence has a calculated net charge of -3. Comparison of the sequence with those of pyruvate kinases from members of the family Trypanosomatidae revealed amino acid identities of 58.4-61.5%, and, to some extent, conservation of residues supposed to be involved in the binding of the allosteric effector fructose 2,6-bisphosphate. Some kinetic properties of Trypanoplasma borelli pyruvate kinase have been determined and appear to be similar to those of the enzyme from Trypanosoma brucei and Leishmania mexicana.