Crystallographic studies of parasite hgprtases pamela

Hypoxanthine Guanine Phosphoribosyltransferases (HGPRTases) are important enzymes in purine nucleotide metabolism. The high resolution X-ray crystal structures of Schistosoma mansoni HGPRTase (1.8 A) and Trypanosoma cruzi HGPRTase (1.4 A) have been solved by molecular replacement. Both parasites rely on the HGPRTase as their sole source of guanine nucleotides and therefore this enzyme has been proposed as a target for antiparasite drug design. Comparing the HGPRTases of the two human parasites to the hu man HGPRTase, it is now possible to analyze the structural differences which may exist between the human and parasite enzymes. Each parasite enzyme structure has been solved in the presence of different Uganda. Their interactions with the protein give mechanistic insight when compared to the human HGPRTase crystal structure, solved in the presence of the enzyme's product. G M P.