Molecular dynamics of the interaction of Plasmodium falciparum and human serine hydroxymethyltransferase with 5-formyl-6-hydrofolic acid analogues: Design of new potential antimalarials

Abstract

Plasmodium falciparum Serine Hydroxymethyltransferase has never been used as target for antimalarial chemotherapy, possibly because its great sequence similarity with the human enzyme. This similarity suggests implies that P. falciparum may not be able to mutate this enzyme to develop resistance for chemotherapy. In this work, we have used differences on the dynamic behavior of the active sites of the crystallographic structure of the human enzyme and a homology model of parasite's enzyme, both in complex with glycine, as N-glycine-[3-hydroxy-2-methyl-5-phosphonooxymethyl-pyridin-4-yl-methane] and 5-formyl-6-hydrofolic acid, to design prototypes for selective inhibitors of this enzyme as new potential antimalarials. Those potential inhibitors are 5-formyl-6-hydrofolic acid derivatives with different charges and tail lengths. Molecular dynamics simulations and interaction energy estimates of the compounds within the active sites of both enzymes showed that compounds with a negative net charge and either shorter tails or longer amphoteric tails, would be more selective towards pfSHMT. © 2006 Sociedade Brasileira de Qúica.