The combination of piperaquine and dihydroartemisinin has recently become the official first-line therapy in several Southeast Asian countries. The pharmacokinetic mismatching of these drugs, whose plasma half-lives are ~20 days and ~1 h, respectively, implies that recrudescent or new infections emerging shortly after treatment cessation will encounter piperaquine as a…
Intraerythrocytic malaria parasites can obtain nearly their entire amino acid requirement by degrading host cell hemoglobin. The sole exception is isoleucine, which is not present in adult human hemoglobin and must be obtained exogenously. We evaluated two compounds for their potential to interfere with isoleucine utilization. Mupirocin, a clinically used…
Recent reports of increased tolerance to artemisinin derivatives–the most recently adopted class of antimalarials–have prompted a need for new treatments. The spirotetrahydro-beta-carbolines, or spiroindolones, are potent drugs that kill the blood stages of Plasmodium falciparum and Plasmodium vivax clinical isolates at low nanomolar concentration. Spiroindolones rapidly inhibit protein synthesis in…
The identification of genetic changes that confer drug resistance or other phenotypic changes in pathogens can help optimize treatment strategies, support the development of new therapeutic agents, and provide information about the likely function of genes. Elucidating mechanisms of phenotypic drug resistance can also assist in identifying the mode of…
Infection with the malaria parasite Plasmodium falciparum leads to widely different clinical conditions in children, ranging from mild flu-like symptoms to coma and death. Despite the immense medical implications, the genetic and molecular basis of this diversity remains largely unknown. Studies of in vitro gene expression have found few transcriptional…
A genomic approach was taken to study the effect of chloroquine (CQ) on Plasmodium falciparum cultures in multiple cell states, following short and long exposures to drug at varying concentrations. Six hundred genes from numerous functional groups were responsive to CQ amongst all cell states assayed in a micro-array analysis;…