Phosphofructokinase of Leishmania donovani and Leishmania braziliensis and its Role in Glycolysis*

Abstract

The phosphofructokinases of L. donovani and L. braziliensis are similar to that of Crithidia fasciculata. Although the enzymes are allosteric with respect to their substrates and require AMP for activation, there is no influence by other heterotropic modifiers. The Mg2+-ATP chelate activates these enzymes in a 1st order process and they can be inhibited by free ATP. The inhibition is reversed by the activator, AMP, competitively. The requirement for the nucleotide in L. donovani can be eliminated by decreasing pH. Phosphofructokinase, a pivotal enzyme in glycolysis for most organisms, probably does not play an important role in glycolysis in Leishmania.