Triclosan offers protection against blood stages of malaria by inhibiting enoyl-ACP reductase of Plasmodium falciparum

The antimicrobial biocide triclosan [5-chloro-2-(2,4-dichlorophenoxy)phenol] potently inhibits the growth of Plasmodium falciparum in vitro and, in a mouse model, Plasmodium berghei in vivo . Inhibition of [ 14 C]acetate and [ 14 C]malonyl-CoA incorporation into fatty acids in vivo and in vitro , respectively, by triclosan implicate FabI as its target. Here we demonstrate that the enoyl-ACP reductase purified from P. falciparum is triclosan sensitive. Also, we present the evidence for the existence of FabI gene in P. falciparum . We establish the existence of the de novo fatty acid biosynthetic pathway in this parasite, and identify a key enzyme of this pathway for the development of new antimalarials.